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Revolutionizing Hemodialysis Water Quality: Development and Evaluation of TiO₂ Nanoparticle-Enhanced Microporous Filters
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作者 Opeyemi Temilade Enang Bakiyat Oluwagbemisola Azeez +3 位作者 Babatunde Temitope Ogunyemi Aminah Abolore Sulayman Dauda Olurotimi Araromi Morufu Olalekan Raimi 《Advances in Nanoparticles》 2025年第1期12-36,共25页
Rationale: Endotoxin contamination in conventionally purified water poses serious risks to hemodialysis patients, leading to complications such as inflammation and sepsis. Addressing these risks is essential for enhan... Rationale: Endotoxin contamination in conventionally purified water poses serious risks to hemodialysis patients, leading to complications such as inflammation and sepsis. Addressing these risks is essential for enhancing patient safety and meeting global dialysis water quality standards. Advanced filtration technologies, such as titanium dioxide (TiO₂)-based nanoparticle filters, offer a promising approach to improve water purification processes in renal care. Objectives: This study aimed to develop and evaluate the effectiveness of a TiO₂-based nanoparticle microporous filtration system for hemodialysis water purification. The objectives included analyzing the system’s performance in reducing chemical contaminants (calcium, magnesium, aluminum, and lead) and microbiological contaminants (total viable count [TVC] and endotoxin units [EU]) across multiple renal centers. Methods: Water samples from three renal centers (RC1, RC2, and RC3) were analyzed pre- and post-filtration. TiO₂ nanoparticles were synthesized using the sol-gel method and characterized via Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy with Energy Dispersive X-ray analysis (SEM/EDX). The microporous filter, fabricated with TiO₂ nanoparticles, silicon dioxide, and polyethylene glycol (PEG), was tested for its ability to remove contaminants. Analytical techniques included spectroscopy for chemical analysis and microbiological assays for contaminant quantification. Results: Post-treatment analysis revealed significant reductions in chemical contaminants, with removal efficiencies averaging 78% for calcium, 80% for magnesium, 81% for aluminum, and 76.6% for lead across all centers. Microbiological contamination was also substantially reduced, with 78–80% removal of TVC and 76–84.6% reduction in EU levels. FTIR analysis confirmed the presence of hydroxyl groups critical for adsorption, while SEM/EDX characterization revealed a crystalline structure with a particle size of 1.45 nm, pore size of 4.11 μm, filter height of 2.56 mm, and bulk density of 0.58 g/cm³. Conclusion: The TiO₂-based nanoparticle filtration system demonstrated high efficacy in removing chemical and microbiological contaminants, significantly improving water quality for hemodialysis. These results highlight its potential as a practical solution for renal centers, especially in resource-constrained settings. Further studies are needed to evaluate its long-term performance and feasibility for widespread adoption. Recommendation: Renal centers should consider adopting TiO2-based nanoparticle filters to address persistent water quality challenges. Pilot implementations across diverse settings can provide insights into operational feasibility. Additional research should explore scalability, maintenance requirements, and cost-effectiveness to optimize integration into healthcare systems. Significance Statement: This study introduces a practical and innovative solution to improve hemodialysis water purification. By effectively reducing both chemical and microbiological contaminants, the TiO2-based filtration system has the potential to enhance patient safety and outcomes, particularly in settings where maintaining high water quality standards remains challenging. 展开更多
关键词 TiO2 Nanoparticles HEMODIALYSIS Water Purification Endotoxin Contamination Photocatalytic Filtration Nanotechnology Microporous Filter Sol-Gel Synthesis Microbiological Contaminants Environmental Remediation
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Incidence and Management of Occupational Blood Exposure (OBE) among Medical Students at the University of Bangui
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作者 Hermione Dahlia Mossoro-Kpinde Caleb Koyambenguia +1 位作者 Yves Kpangba Mangbé Saint Calvaire Henri Diemer 《Occupational Diseases and Environmental Medicine》 2024年第2期68-77,共10页
Introduction: Like healthcare workers, medical students are also exposed to a risk of accidental contamination during their hospital internships. However, they do not benefit from prevention services in the same way a... Introduction: Like healthcare workers, medical students are also exposed to a risk of accidental contamination during their hospital internships. However, they do not benefit from prevention services in the same way as workers in this sector, although they actively participate in the routine care provided to patients in the various hospital departments. The objective of our study is to determine the incidence of these accidents and their medical and administrative management among these victims (medical students) not classified in the category of workers. Materials and Method: This was a cross-sectional study carried out over three months from January 15 to March 14, 2023. The study population consisted of all medical students at the Faculty of Health Sciences at the University of Bangui. Regularly enrolled students from 2nd to 7th year, on placement in hospitals in the Central African Republic and who gave their informed consent were included. Data were collected through a self-administered questionnaire. Results: A cross-sectional study was carried out among medical students concerning the incidence and management of accidents involving exposure to blood in the Central African Republic. Of the 254 students included, three (9%) had already been correctly vaccinated against the viral hepatitis B virus, 198 (77.9%) reported still having access to personal protective equipment, 133 students (52.4%) reported being victims of OBE in the past 12 months. The main types of OBE were stings (62%), followed by liquid splashes (32%) and cuts (6%). Among the 133 victims, 92.9% carried out immediate hand disinfection or abundant eye washing, 41.9% obtained the serology of the source patient and 37% reported the accident to their supervisor. Conclusion: It is important that students benefit from better prevention and management of these accidents. 展开更多
关键词 Incidence of Blood Exposure Accidents Medical Student TREATMENT Bangui
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基于FireNet的古建筑火灾检测方法研究及改进 被引量:4
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作者 陈庆典 钟晨 +1 位作者 刘慧 王晓辉 《消防科学与技术》 CAS 北大核心 2024年第2期183-188,共6页
针对古建筑火灾检测需要快速、准确及实时的需求,建立了一个专门用于古建筑火灾检测的数据集,用于古建筑火灾检测的深度学习研究。利用CBAM注意力机制模块,结合多尺度特征融合,对FireNet网络进行改进,提出适用于古建筑火灾检测的轻量级F... 针对古建筑火灾检测需要快速、准确及实时的需求,建立了一个专门用于古建筑火灾检测的数据集,用于古建筑火灾检测的深度学习研究。利用CBAM注意力机制模块,结合多尺度特征融合,对FireNet网络进行改进,提出适用于古建筑火灾检测的轻量级FireNet-AMF网络,在FireNet数据集和本文构建的古建筑火灾检测数据集上验证了FireNet-AMF网络的火灾检测能力。与改进前的网络相比,FireNet-AMF网络在FireNet数据集上对火灾识别的准确率达到了95.08%,与原网络相比提高了1.17%,在本文构建的古建筑火灾检测数据集上的准确率达到了95.62%,比原网络提高了1.62%。该网络在保证轻量级的同时也保证了在古建筑火灾检测中较高的检测精度。 展开更多
关键词 古建筑 火灾检测 图像分类 FireNet 注意力机制 多尺度特征融合
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Induction System for a Fusion Reactor: Quantum Mechanics Chained up
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作者 Friedrich Björn Grimm 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期158-166,共9页
In the quest for a sustainable and abundant energy source, nuclear fusion technology stands as a beacon of hope. This study introduces a groundbreaking quantum mechanically effective induction system designed for magn... In the quest for a sustainable and abundant energy source, nuclear fusion technology stands as a beacon of hope. This study introduces a groundbreaking quantum mechanically effective induction system designed for magnetic plasma confinement within fusion reactors. The pursuit of clean energy, essential to combat climate change, hinges on the ability to harness nuclear fusion efficiently. Traditional approaches have faced challenges in plasma stability and energy efficiency. The novel induction system presented here not only addresses these issues but also transforms fusion reactors into integrated construction systems. This innovation promises compact fusion reactors, marking a significant step toward a clean and limitless energy future, free from the constraints of traditional power sources. This revolutionary quantum induction system redefines plasma confinement in fusion reactors, unlocking clean, compact, and efficient energy production. 展开更多
关键词 Fusion Reactor Plasma Confinement Quantum Mechanics Clean Energy
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富碳质地质样品Re-Os同位素体系研究进展 被引量:3
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作者 李欣尉 李超 +2 位作者 周利敏 赵鸿 屈文俊 《岩矿测试》 CAS CSCD 北大核心 2023年第2期221-238,共18页
Re-Os同位素定年技术在富有机质沉积岩、低变质沉积岩、湖相沉积物、煤、油气藏样品等富碳质地质样品的尝试和成功应用,使其成为直接厘定地层沉积时代、重大地质事件发生时限和机制、古环境重建、油气藏直接定年、油气演化过程推演等研... Re-Os同位素定年技术在富有机质沉积岩、低变质沉积岩、湖相沉积物、煤、油气藏样品等富碳质地质样品的尝试和成功应用,使其成为直接厘定地层沉积时代、重大地质事件发生时限和机制、古环境重建、油气藏直接定年、油气演化过程推演等研究的关键技术手段。然而,受到富碳质地质样品中极低的Re和Os丰度、采样方式以及地质作用等因素的影响,很多样品的Re-Os等时线年龄和初始Os同位素比值精度超过10%,不能有效地评价海水Os的真实来源和地质作用程度,影响了对不同沉积体系及油气演化过程中Re和Os的化学行为和Re-Os等时线年龄地质意义的理解。由此,本文从富碳质地质样品的Re-Os化学行为和地质应用进展出发,对富碳质地质样品Re-Os同位素分析过程中的采样和取样方式、溶样方法、分离富集方式和标准物质选择四方面进行了总结和完善。指出以沉积速率为采样间距参考,通过预处理方式提高样品的均匀性,使用流程空白更低、对同位素分馏影响更小的溶样方法和分离富集方式进行Re-Os同位素分析,以基质匹配的地质标样进行数据监控可进一步提高样品Re-Os同位素分析质量,有助于不同类型富碳质地质样品Re和Os赋存机制研究、Re-Os同位素分析技术开发及地质应用拓展。 展开更多
关键词 RE-OS同位素体系 富碳质地质样品 油气演化 Re、Os化学行为 地质应用 富碳质地质标样
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Review of Maternal Deaths over 3 and a Half Years at the Kara University Hospital Center, Northern Togo: About 65 Cases
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作者 Logbo-Akey Kossi Edem Dédé Régine Diane Ajavon +4 位作者 Kambote Yendoubé Tenete Assiaham Douaguibe Banguilane Agoro Sibabe Aboubakari Abdoul-Samadou 《Open Journal of Obstetrics and Gynecology》 2024年第5期682-692,共11页
Objective: To analyze maternal deaths, identify causes and dysfunctions leading to these deaths in order to contribute to the implementation of strategies to reduce maternal mortality at CHU Kara. Method: Cross-sectio... Objective: To analyze maternal deaths, identify causes and dysfunctions leading to these deaths in order to contribute to the implementation of strategies to reduce maternal mortality at CHU Kara. Method: Cross-sectional descriptive study involving 65 cases of maternal deaths recorded at CHU-Kara from January 1, 2018 to June 30, 2021. Results: Our study focused on 65 cases of maternal deaths recorded at the maternity ward of CHU-Kara. The average age was 30 years, with a range of 15 to 45 years. They were mostly housewives (52.3%), uneducated (38.5%), multiparous (41.5%), and referred (86.2%). The causes were mainly direct obstetric causes (81.54%), with preeclampsia and its complications (28.30%) and immediate postpartum hemorrhage (20.75%) being the most common. However, uterine rupture (20.5%) and post-abortion sepsis (16.4%) were the most lethal etiologies. Delayed evacuation (46.43%), inadequate transportation (91%), and insufficient prenatal care (72.31%) were the dysfunctions before referral. Within the CHU Kara, delays in management (58.46%), unavailability of blood and labile products (18%), and insufficient monitoring were the dysfunctions identified. Ninety-five point four percent (95.4%) of the deaths were preventable. Conclusion: The magnitude of intrahospital maternal deaths, the various dysfunctions observed in the occurrence of maternal deaths before referral/evacuation and within the hospital highlight the importance of effectively implementing recommendations from audits in the fight against maternal mortality. The majority of the deaths were preventable (95.38%). 展开更多
关键词 Review of Maternal Deaths CHU Kara TOGO
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National Soil Organic Carbon Stocks Inventories under Different Mangrove Forest Types in Gabon
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作者 Rolf Gaël Mabicka Obame Neil-Yohan Musadji +5 位作者 Jean Hervé Mve Beh Lydie-Stella Koutika Jean Aubin Ondo Farrel Nzigou Boucka Michel Mbina Mounguengui Claude Geffroy 《Open Journal of Forestry》 2024年第2期127-140,共14页
Gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear... Gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear. To address this gap, determining the SOC spatial variation in Gabonese’s estuarine is essential for better understanding the global carbon cycle. The present study compared soil organic carbon between northern and southern sites in different mangrove forest, Rhizophora racemosa and Avicennia germinans. The results showed that the mean SOC stocks at 1 m depth were 256.28 ± 127.29 MgC ha<sup>−</sup><sup>1</sup>. Among the different regions, SOC in northern zone was significantly (p p < 0.001). The deeper layers contained higher SOC stocks (254.62 ± 128.09 MgC ha<sup>−</sup><sup>1</sup>) than upper layers (55.42 ± 25.37 MgC ha<sup>−</sup><sup>1</sup>). The study highlights that low deforestation rate have led to less CO<sub>2</sub> (705.3 Mg CO<sub>2</sub>e ha<sup>−</sup><sup>1</sup> - 922.62 Mg CO<sub>2</sub>e ha<sup>−</sup><sup>1</sup>) emissions than most sediment carbon-rich mangroves in the world. These results highlight the influence of soil texture and mangrove forest types on the mangrove SOC stocks. The first national comparison of soil organic carbon stocks between mangroves and upland tropical forests indicated SOC stocks were two times more in mangroves soils (51.21 ± 45.00 MgC ha<sup>−</sup><sup>1</sup>) than primary (20.33 ± 12.7 MgC ha<sup>−</sup><sup>1</sup>), savanna and cropland (21.71 ± 15.10 MgC ha<sup>−</sup><sup>1</sup>). We find that mangroves in this study emit lower dioxide-carbon equivalent emissions. This study highlights the importance of national inventories of soil organic carbon and can be used as a baseline on the role of mangroves in carbon sequestration and climate change mitigation but the variation in SOC stocks indicates the need for further national data. 展开更多
关键词 Mangroves Forest Soil Organic Carbon Stocks Rizophora Racemose Avicenia germinans GABON
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Hybrid Prisms: Revolutionizing Optical Systems across Spectral Ranges
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作者 Friedrich Björn Grimm 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1359-1366,共8页
This research article introduces and explores the concept of a hybrid prism, which combines the properties of a lens and a reflective prism, designed for optical systems that operate in different spectral ranges of el... This research article introduces and explores the concept of a hybrid prism, which combines the properties of a lens and a reflective prism, designed for optical systems that operate in different spectral ranges of electromagnetic waves. The hybrid prism allows for precise focusing of light rays in a glass body and X-rays in a vacuum, enabling it to serve as an objective in various optical systems for imaging objects. The article delves into the structure and working principles of the hybrid prism, discussing its potential applications, including as an intraocular prism for macular degeneration, a lidar system for vehicle navigation, and objectives for cameras, telescopes, microscopes, X-ray devices, and X-ray microscopes. The revolutionary hybrid prism unlocks precise imaging of light and X-rays, reshaping optical systems and enabling groundbreaking applications. 展开更多
关键词 Imaging Technology Electromagnetic Waves X-Rays LIGHT Lenses
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贵州正安县奥陶系—志留系界线碳质泥岩Re-Os同位素精确厘定及其古环境反演 被引量:6
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作者 李欣尉 李超 +1 位作者 周利敏 赵鸿 《岩矿测试》 CAS CSCD 北大核心 2020年第2期251-261,共11页
我国上扬子地台地区在奥陶系—志留系之交广泛发育蕴含丰富页岩气资源的五峰组—龙马溪组富有机质沉积岩。采用Re-Os同位素体系对该套沉积地层进行研究,不仅能得到精确的地层沉积年龄,同时根据Re、Os元素的富集机制,对该时期沉积环境进... 我国上扬子地台地区在奥陶系—志留系之交广泛发育蕴含丰富页岩气资源的五峰组—龙马溪组富有机质沉积岩。采用Re-Os同位素体系对该套沉积地层进行研究,不仅能得到精确的地层沉积年龄,同时根据Re、Os元素的富集机制,对该时期沉积环境进行有效反演,可以为这一阶段发生的地球历史上第二大规模的生物绝灭事件的触发机制提供更合理的解释。本文在贵州正安县班竹1井岩心采集11件碳质泥岩样品,岩心样品连续且完整跨越奥陶系五峰组—志留系龙马溪组界线地层,通过对该样品开展高精度Re-Os同位素研究,获得了奥陶系—志留系地层界线Re-Os同位素年龄为443.68±6.24Ma[2σ,n=7,(187 Os/188 Os)i=0.699±0.019,MSWD=0.55],其结果与国际地层委员会发布的年龄(443.7±1.5Ma)高度一致,为奥陶系—志留系界线年龄提供了直接、准确的年龄依据。Os同位素特征反映了大量陆源碎屑参与成岩过程、多期火山活动的发生及冰期向间冰期的转换。连续沉积地层Re-Os同位素特征的变化反映了研究区奥陶系五峰组—志留系龙马溪组沉积环境经历富氧—缺氧—富氧的变化,指示赫南特期冰川事件和火山喷发共同造成了生物大绝灭并促进了有机质的富集,为五峰组—龙马溪组富有机质沉积岩提供了生烃潜力。 展开更多
关键词 RE-OS同位素定年 奥陶系—志留系界线 Os同位素特征 古环境演化 五峰组—龙马溪组富有机质沉积岩 热电离质谱法
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沥青Re-Os同位素年龄地质意义解读 被引量:6
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作者 李超 孙鹏程 +5 位作者 孟会明 王登红 周利敏 李欣尉 赵鸿 屈文俊 《岩石学报》 SCIE EI CAS CSCD 北大核心 2022年第6期1595-1604,共10页
Re、Os亲有机质的特性使得Re-Os同位素在富有机质地质样品中得到了广泛应用;沥青由大量重组分有机质组成,对Re、Os具有较强的富集能力,并且沥青样品中Re-Os同位素封闭性较好,因此沥青Re-Os同位素已经成为当今国际上研究的一个热点。然而... Re、Os亲有机质的特性使得Re-Os同位素在富有机质地质样品中得到了广泛应用;沥青由大量重组分有机质组成,对Re、Os具有较强的富集能力,并且沥青样品中Re-Os同位素封闭性较好,因此沥青Re-Os同位素已经成为当今国际上研究的一个热点。然而,沥青Re-Os同位素年龄究竟是代表烃源岩的沉积时代、油气成藏时代、还是油气藏破坏后油气运移时代,至今还没有明确的定论。本文对新疆乌尔禾沥青矿、四川矿山梁沥青矿样品进行了Re-Os同位素分析,结果显示,乌尔禾沥青矿Re-Os同位素年龄为269±9Ma,老于周围白垩系砂岩地层沉积时代,Os同位素初始比值^(187) Os/^(188 )Os(Os i)为0.367±0.028,小于二叠纪海水的Os i同位素比值,表明得到的乌尔禾沥青Re-Os同位素年龄反映的是乌尔禾油气藏的成藏时代。矿山梁沥青矿Re-Os同位素年龄为537.3±5.2Ma,老于围岩(寒武系、奥陶系、志留系地层)沉积时代,Os同位素初始比值为0.716±0.028,与早寒武世海水的Os_(i)同位素比值一致,表明得到的矿山梁沥青Re-Os同位素年龄代表烃源岩的沉积时代。结合前人发表的沥青Re-Os同位素数据,沥青Re-Os同位素等时线年龄可能反映烃源岩的沉积时代,也可能代表油气藏的形成时代,这主要取决于油气成藏过程中,具有不同Re-Os同位素特征的原油是否能够混合均匀。沥青Re-Os同位素年龄能否反映油气藏遭受破坏而发生运移的时代,主要取决于沥青的热演化程度以及油气藏破坏过程中原油的混合程度。沥青Re-Os同位素研究不仅能够为油气成藏时代的厘定提供了一种有力的工具,而且对于油气烃源岩的判别以及油气成因研究都具有十分重要的意义。 展开更多
关键词 沥青 RE-OS 同位素 年代学 油气藏 定年
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峨眉蔷薇Ro-DREB1C的克隆与生物信息学分析 被引量:2
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作者 周宁宁 王俊云 +3 位作者 李淑斌 陈敏 张颢 王其刚 《西南农业学报》 CSCD 北大核心 2018年第11期2248-2254,共7页
【目的】丰富月季CBF基因研究的基础数据库,对峨眉蔷薇原变种(Rosa omeiensis Rolfe f. omeiensis) CBF/DREB基因进行克隆和生物信息学分析。【方法】设计特异引物克隆Ro-DREB1C基因的完整CDS区及部分5'端和3'端UTR区序列,使用... 【目的】丰富月季CBF基因研究的基础数据库,对峨眉蔷薇原变种(Rosa omeiensis Rolfe f. omeiensis) CBF/DREB基因进行克隆和生物信息学分析。【方法】设计特异引物克隆Ro-DREB1C基因的完整CDS区及部分5'端和3'端UTR区序列,使用生物信息学软件分析该基因编码蛋白的理化性质、二三级结构和预测亚细胞定位,构建系统进化树确定Ro-DREB1C隶属的基因家族。【结果】获得峨眉蔷薇Ro-DREB1C基因CDS区603 bp,Gen Bank登录号为KX397104,编码200个氨基酸。蛋白质分子式为C968H1539N263O299S11,其中丝氨酸、亮氨酸和丙氨酸的频率较高,分别占11. 5%、11. 0%和9. 5%,属于不稳定类、弱酸性、亲水蛋白;二级结构以无规则卷曲(71. 5%)为主,不能被归入明确的二级结构如折叠片或螺旋的多肽区段;三级结构预测模板为d1gcca,识别预测序列范围为59~119,识别长度61 bp;该蛋白质无跨膜区和信号肽的存在,亚细胞定位Ro-DREB1C分布在细胞核中的分布最多。与RhCBF比较:Ro-DREB1C的编码区没有单碱基的缺失或插入,共存在21个潜在SNP位点,导致10个差异氨基酸。系统进化分析表明Ro-DREB1C隶属于AP2家族DREB亚家族A-1亚组成员。【结论】峨眉蔷薇可作为优秀的月季耐寒育种材料加以保存和利用。 展开更多
关键词 峨眉蔷莪 DREB/CBF 基因克隆 生物信息学
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Syphilis and HIV Infection among Pregnant Women Previously Screened Negative during Their First Antenetal Care Visit (ANC) at Some Selected Health Facilities in the Buea Health District, Cameroon
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作者 Mbanya Gladice Mbanya Njunda Anna Longdoh +1 位作者 Ngouakam Hermann Simon Eyongabane Ako 《Journal of Biosciences and Medicines》 2023年第7期50-65,共16页
Syphilis and HIV are amongst the world’s most widespread diseases, particularly in low-income countries. Syphilis and HIV infections during pregnancy have been associated with numerous adverse pregnancy outcomes. Of ... Syphilis and HIV are amongst the world’s most widespread diseases, particularly in low-income countries. Syphilis and HIV infections during pregnancy have been associated with numerous adverse pregnancy outcomes. Of concern now are the rising rates of congenital syphilis and HIV in Cameroon. Cameroon only mandates testing pregnant women for syphilis and HIV during their first ANC visit. This study was aimed at determining the incidence of new syphilis and HIV infections and factors associated with pregnant women who previously tested negative during their first ANC visit. A cohort design was used, where 335 pregnant women were followed up for a period from December 2019 to August 2020. A blood sample was drawn and the serum was analyzed using the WANTAI ELISA and AIDTM HIV 1 + 2 Ag/Ab ELISAPlus test methods for syphilis and HIV respectively at three intervals. A questionnaire was used to identify risk factors. Data was analyzed using SPSS 23.0. Out of the 335 pregnant women who were followed up during this study, 49 (14.6%) were later diagnosed with syphilis (32 in 2<sup>nd</sup> trimester and 17 in 3<sup>rd</sup> trimester). 54 (16.1%) were diagnosed with HIV infection (13 at two months post-1<sup>st</sup>-trimester visit, 23 in the 2<sup>nd</sup> trimester and 18 in the 3rd trimester). Lastly, 10 (2%) were co-infected with syphilis and HIV of which 8 occurred during 2<sup>nd</sup> trimester and 2 in the 3<sup>rd</sup> trimester. The factors associated with contracting new syphilis infections include;younger age group aOR (1.302, 95% CI), leaving in an urban area aOR (3.158, 95% CI), lower level of education (Primary and no formal) with aOR of (9.055, 95% CI) (P = 0.001) and (6.764, 95% CI) (P = 0.006) respectively, inadequate knowledge on the diseases aOR (2.176, 95% CI), women unaware of their partner status aOR (3.190, 95% CI). Most factors associated with contracting new HIV infections were similar to the factors associated with contracting new syphilis infections post 1<sup>st</sup> ANC visit aOR (1.174, 95% CI) and pregnant women with more than one sexual partner aOR (7.342, 95% CI) were observed for HIV infection.. There is an increased incidence of new infection of syphilis and HIV post first ANC screening in the Buea Health District, Cameroon. The need for constant education on the identifiable factors and these diseases, and screening during every ANC visit irrespective of their previous laboratory results is warranted. 展开更多
关键词 SYPHILIS HIV STI Pregnant Women Post First-Antenatal Care Screening ELISA Buea
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Obstacles to the Integrated Care of Children Aged 6 to 59 Months Suffering from Acute and Severe Malnutrition at the Chu-Me and HATC of N’Djamena/Chad
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作者 Madjiadoumbeye Romain Imar Djibrine Soudy 《Open Journal of Nursing》 2024年第4期127-138,共12页
Introduction: the problem of Severe Acute Malnutrition (SAM) and its consequences concern and challenge all social actors worldwide. The objective of the study was to identify the real obstacles that actors face in th... Introduction: the problem of Severe Acute Malnutrition (SAM) and its consequences concern and challenge all social actors worldwide. The objective of the study was to identify the real obstacles that actors face in the integrated management of children aged 6 - 59 months suffering from SAM at the University Hospital of Mother and Child (CHUME) and the Chad-China Friendship Hospital (HATC) of N’Djamena. Methodology: this is a cross-sectional descriptive and interpretative study conducted from January to October 2023 at the CHUME and HATC of N’Djamena. It is based on questionnaires and direct observation of two hundred and thirty-six (236) parents or guardians of malnourished children admitted to these health facilities. All 236 agreed to participate freely in this study. Results: it appears from this study that the obstacles to the integrated management of malnourished children were: poor care-care relationship (26.7%) permanent product breaks (22.9%), the direct costs of services ranged from 30,000 to 60,000 FCFA (41.53%), drugs used for the treatment of patients came from the street (66.10%), malaria and anemia occupy an important place (27.5%), 57.2% respondents had monthly income below 60,000 CFAF. Conclusion: the present study carried out has identified the real bottlenecks to the integrated management of children suffering from SAM in the therapeutic nutritional units of the city of N’Djamena. . 展开更多
关键词 Integrated Management Child 6 - 59 Months SAM
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Analysis of the Quality of Physical and Chemical Parameters of Groundwater in Three Localities in the Sub-Prefecture of Zanzra (Ivory Coast)
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作者 Djedjess Essoh Jules-César Meledje Bi Irié Marc Gouli +3 位作者 Drissa Ouattara Kra Vanh Eric-Simon Zran Adjourma Konate Albert Trokourey 《Journal of Materials Science and Chemical Engineering》 2024年第4期1-17,共17页
The availability of groundwater of acceptable quality has become a difficult challenge to meet in many countries, particularly Côte d’Ivoire. The State of Côte d’Ivoire and rural populations are building h... The availability of groundwater of acceptable quality has become a difficult challenge to meet in many countries, particularly Côte d’Ivoire. The State of Côte d’Ivoire and rural populations are building hydraulic infrastructure for this purpose. However, the quality of water coming from these infrastructures remains to be determined. This study therefore aims to analyze certain physicochemical parameters of the groundwater of Gloazra, Kouezra and Trahonfla. These are temperature, pH, electrical conductivity, TDS, salinity level, hardness, alkalinity, chloride content and bicarbonate. To determine the pH, electrical conductivity, temperature, TDS, and salinity rate, an electrochemical analysis was carried out. The titrimetric analysis made it possible to determine the chloride and bicarbonate content, alkalinity, and hardness. The results indicate that the studied groundwater is soft and acidic with good mineralization. This water does not present a health hazard to consumers but can affect hydraulic equipment and household containers. 展开更多
关键词 Ivory Coast Gloazra Trahonfla Kouezra Physicochemical Parameters Water WHO Standards
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中国斑岩铜(钼)矿床中辉钼矿Re含量变化及控制因素 被引量:4
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作者 孙鹏程 李超 +5 位作者 周利敏 屈文俊 孙豪 李欣尉 赵鸿 杜安道 《矿床地质》 CAS CSCD 北大核心 2021年第2期273-292,共20页
铼作为战略性关键金属之一,越来越受到人们的关注。Re主要以类质同象的形式赋存在辉钼矿中,然而,不同成因、不同类型矿床的辉钼矿中Re含量差异较大。在钨、锡矿床中Re含量较低,在斑岩型铜(钼)矿床中Re含量较高,后者是全球Re资源的主要... 铼作为战略性关键金属之一,越来越受到人们的关注。Re主要以类质同象的形式赋存在辉钼矿中,然而,不同成因、不同类型矿床的辉钼矿中Re含量差异较大。在钨、锡矿床中Re含量较低,在斑岩型铜(钼)矿床中Re含量较高,后者是全球Re资源的主要载体。前人对于辉钼矿中Re元素的研究主要基于Re-Os同位素年代学,而对于不同区域、不同时代、不同类型斑岩型铜矿床中辉钼矿Re含量的变化规律及其控制因素的研究较少。文章通过汇总前人发表的斑岩型铜(钼)矿床的Re-Os同位素数据,从含矿斑岩的Sr、Nd、Hf等数据与辉钼矿中平均Re含量的关系等角度,探讨了其变化规律及控制因素。结果表明:中国斑岩型铜(钼)中Re含量随着成矿物质从地幔到地壳,依次减少;成矿流体的氧逸度、辉钼矿的产状、与其伴生的硫化物种类及不同的成矿阶段等因素共同控制了辉钼矿中Re的含量。 展开更多
关键词 地球化学 斑岩型矿床 辉钼矿 Re含量 成矿带 物质来源
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云南金顶铅锌矿成矿时代厘定:来自沥青Re-Os同位素证据 被引量:9
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作者 孙鹏程 李超 +7 位作者 周利敏 屈文俊 王登红 高兰 李伟 李欣尉 赵鸿 杜安道 《地球科学》 EI CAS CSCD 北大核心 2021年第12期4247-4259,共13页
MVT型铅锌矿由于成矿温度低,目前没有发现十分合适的定年矿物,此外,由于多期成矿作用叠加以及成矿物质存在多元混合,严重制约了对此类矿床成矿年代学研究.前人对云南金顶超大型MVT铅锌矿床成因、物质来源、成矿条件等方面研究取得了重... MVT型铅锌矿由于成矿温度低,目前没有发现十分合适的定年矿物,此外,由于多期成矿作用叠加以及成矿物质存在多元混合,严重制约了对此类矿床成矿年代学研究.前人对云南金顶超大型MVT铅锌矿床成因、物质来源、成矿条件等方面研究取得了重要成果,但对其形成时代各有所云,至今仍未定论.笔者在总结了大量前人研究成果的基础上,通过对跑马坪和架崖山矿段沥青样品开展Re-Os同位素定年研究,表明古油藏形成于59.1 Ma,金顶铅锌矿床的形成时代可能为27.7 Ma.早期的油气藏为后期铅锌矿的形成提供了十分重要的条件,穹隆构造为金属成矿提供了储矿空间,由于遭受构造及热液作用的破坏,油气裂解释放大量的还原性物质,为Pb、Zn等成矿物质迁移、富集、沉淀提供了重要载体,进而形成了金顶超大型铅锌矿床.研究结果表明,沥青Re-Os同位素不仅能够为MVT型铅锌矿床成矿年龄的厘定提供一种有效的技术途径,同时还能够为油气藏的生成、破坏等事件发生时代提供有利依据. 展开更多
关键词 MVT型铅锌矿 RE-OS 成矿时代 动力学背景 沥青 矿床
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滇中昆阳磷矿成矿时代及沉积环境Re-Os同位素示踪研究 被引量:8
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作者 严清高 李超 +3 位作者 江小均 王忠强 李云驹 李伟 《岩矿测试》 CAS CSCD 北大核心 2018年第4期462-474,共13页
川滇黔地区下寒武地层中广泛分布一系列磷矿床,其中滇中昆阳磷矿是我国下寒武统梅树村期黑色页岩中规模最大的海相沉积型磷矿床,其成矿时代以及沉积环境对于矿床成因研究以及区域找矿具有重要意义。Re-Os同位素不仅能够对富有机质沉积... 川滇黔地区下寒武地层中广泛分布一系列磷矿床,其中滇中昆阳磷矿是我国下寒武统梅树村期黑色页岩中规模最大的海相沉积型磷矿床,其成矿时代以及沉积环境对于矿床成因研究以及区域找矿具有重要意义。Re-Os同位素不仅能够对富有机质沉积岩地层进行直接定年,而且还能为物质来源及沉积环境示踪提供一种有效的技术手段。本文对昆阳磷矿中谊村段磷块岩和石岩头段黑色页岩开展热表面电离质谱法Re-Os同位素示踪及定年探索性研究,获得了石岩头段黑色页岩Re-Os等时线年龄为521.9±5.4Ma,直接限定了昆阳磷矿黑色页岩沉积时代。磷块岩187Os/188Os初始比值为0.6576~0.7671,黑色页岩187Os/188Os初始比值为0.887,另外磷块岩187Re/188Os值为2.582~240.5,而上覆黑色页岩187Re/188Os值为96.24~341.8,而且磷块岩、黑色页岩微量元素δEu和δCe值在垂向剖面上显示由低变高的变化特征,这些证据表明昆阳磷矿形成正处于大陆快速剥蚀时期,指示大量陆源碎屑汇入海洋参与成岩-成矿过程。综合前人研究,本文认为,在寒武纪,大气氧含量快速升高,加剧陆壳风化,大量高放射性陆源Os的输入造成该时期内187Os/188Os初始比值逐渐升高。另外由于全球海平面上升,导致滇中早寒武世梅树村组沉积期古海洋环境由浅水氧化向深水还原逐渐过渡,而昆阳磷矿形成于该阶段海进旋回沉积早期。 展开更多
关键词 RE-OS同位素 黑色页岩 磷块岩 海侵 梅树村组
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红掌细菌性疫病病原菌遗传多样性的RAPD和Rep-PCR分析 被引量:1
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作者 陈艳梅 高月荣 +1 位作者 尹俊梅 牛俊海 《热带作物学报》 CSCD 北大核心 2018年第9期1813-1819,共7页
由地毯草黄单胞菌花叶万年青致病变种引起的细菌性疫病是红掌生产中最具破坏性的病害。本研究对来自全国8个省市主产区的93个红掌细菌性疫病菌株,采用RAPD和Rep-PCR(ERIC、BOX、REP)分子标记进行了遗传多样性分析。筛选出的13个RAPD引... 由地毯草黄单胞菌花叶万年青致病变种引起的细菌性疫病是红掌生产中最具破坏性的病害。本研究对来自全国8个省市主产区的93个红掌细菌性疫病菌株,采用RAPD和Rep-PCR(ERIC、BOX、REP)分子标记进行了遗传多样性分析。筛选出的13个RAPD引物共扩增出131个清晰、重复性好的条带,而Rep-PCR共扩增出65个条带,所有位点多态性比率为100%。基于RAPD和Rep-PCR结果计算的群体遗传距离显著相关,综合2种标记类型的分型结果进行UPGMA聚类分析,表明我国红掌细菌性疫病具有高度的遗传多样性,在遗传相似性系数范围0.519 1~0.984 7,在0.63水平时可以将所有菌株划分为3个组群,分别包括58、28、7个个体,病菌群体的遗传多样性与其寄主品种、地理来源没有明显相关性。本研究为红掌细菌性疫病监测和抗病育种提供了科学依据。 展开更多
关键词 红掌 细菌性疫病 遗传多样性 RAPD REP-PCR
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柯萨奇B组3型病毒SYBR GreenⅠRT-PCR检测方法的建立 被引量:2
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作者 张伟 李咏洁 +7 位作者 杨凤梅 李艳艳 靳玮华 徐鸿界 李明学 刘权 赵远 和占龙 《医学研究杂志》 2022年第1期55-59,共5页
目的建立一种灵敏、特异的柯萨奇B组3型(CV-B3)病原SYBR GreenⅠRT-PCR实时荧光定量检测方法,用于快速、准确地检测CV-B3。方法设计柯萨奇B组病毒通用引物以及VP1基因的T7启动子特异性引物,以体外转录获得的RNA为标准品,绘制标准曲线,建... 目的建立一种灵敏、特异的柯萨奇B组3型(CV-B3)病原SYBR GreenⅠRT-PCR实时荧光定量检测方法,用于快速、准确地检测CV-B3。方法设计柯萨奇B组病毒通用引物以及VP1基因的T7启动子特异性引物,以体外转录获得的RNA为标准品,绘制标准曲线,建立CV-B3的荧光定量PCR检测方法;对检测方法的敏感度、特异性、重复性进行评价。结果该检测方法在10~10^(9)拷贝/微升范围内具有良好的扩增效率和线性关系,最低检测限为10拷贝/微升,标准曲线r^(2)=0.999,扩增效率为95.7%;且对柯萨奇病毒A组6型(CV-A6)、柯萨奇病毒A组10型(CV-A10)、肠道病毒71型(EV-71)均无交叉反应,重复性实验变异系数(CV%)<2%。结论本实验建立的检测方法敏感度较高,同时具备良好的特异性及重复性,可用于CV-B3病原的临床及实验室样本的定性定量检测。 展开更多
关键词 柯萨奇病毒B组3型 SYBR GreenⅠ RT-PCR
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Extraction and recovery of cerium(Ⅳ)and thorium(Ⅳ)from sulphate medium by anα-aminophosphonate extractant 被引量:18
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作者 LU Youcai ZHANG Zhifeng +1 位作者 LI Yanling LIAO Wuping 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第1期34-40,共7页
In the present work,a novelα-aminophosphonate extractant(Cextrant 230)was synthesized for the extraction and recovery of cerium and thorium from sulphate medium.The introduction of amine group into the phosphate mole... In the present work,a novelα-aminophosphonate extractant(Cextrant 230)was synthesized for the extraction and recovery of cerium and thorium from sulphate medium.The introduction of amine group into the phosphate molecule would enhance the extraction of Ce(Ⅳ)and Th(Ⅳ).The effects of extractant concentration,H_(2)SO_(4)concentration and temperature on the metal extraction were investigated in detail.It was found that the extraction of Ce(Ⅳ),Th(Ⅳ)and REs(La,Gd,Yb)in sulphate medium decreased in the following order:Ce(Ⅳ)〉Th(Ⅳ)〉REs(Ⅲ).A solvent extraction process to extract and recover cerium and thorium from bastnasite leaching was proposed,in which the purities of cerium and thorium products reached 99.9%and 99%with yield of 92%and 98%,respectively. 展开更多
关键词 THORIUM rare earths α-aminophosphonates solvent extraction separation
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