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被子植物隐性雌雄异株性系统的多样性、系统演化及进化意义

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生物多样性 2024年第6期32卷 56-70页

作者：何花谭敦炎杨晓琛吉首大学武陵山区植物资源保护与利用湖南省高校重点实验室湖南吉首416000

隐性雌雄异株指植株表型为非雌雄异株,但形态上两性花通常雄性不育或雌性不育,植株个体实际仅行使雌性或雄性功能。两性花植株向雌雄异株的转变在被子植物中广泛存在,隐性雌雄异株作为潜在的中间阶段对于理解植物性系统的演化具有重要... 详细信息

隐性雌雄异株指植株表型为非雌雄异株,但形态上两性花通常雄性不育或雌性不育,植株个体实际仅行使雌性或雄性功能。两性花植株向雌雄异株的转变在被子植物中广泛存在,隐性雌雄异株作为潜在的中间阶段对于理解植物性系统的演化具有重要意义。据APGIV分类系统,这些物种在被子植物的22目36科65属约221种植物中有过报道,分别约占被子植物总目数的34.4%、总科数的8.7%、总属数的0.5%和总种数的0.1%;多为分布于热带或亚热带地区依靠生物传粉的木本植物,且至少存在花蜜或花粉作为访花报酬。该性系统形态学的性表达类型多样:可分为雄花两性花异株(类型Ⅰ)、两性花植株(类型Ⅱ)、雌花两性花异株(类型Ⅲ)及其他类型(类型Ⅳ)4种,分别约占已报道隐性雌雄异株物种数的48.9%、47.5%、2.7%和0.9%。从系统发育看,该性系统在被子植物木兰分支、单子叶植物分支及真双子叶植物分支均有分布,且主要分布于较为进化的核心真双子叶植物类群中。隐性雌雄异株物种不育性器官的进化意义存在多种假说,包括祖先假说、遗传约束假说、促进风媒花粉落置假说、传粉者吸引假说、拟态与欺骗假说等,但相关实证研究较少。本文对隐性雌雄异株物种不同类群的性表达形式、不育性器官败育类型进行了归纳,并对具该性系统的类群在被子植物中的分布与系统演化进行了分析与总结,同时对有关隐性雌雄异株物种不育性器官进化意义的5个假说进行了介绍与评价,最后对今后的相关研究方向进行了展望。以期为深入研究被子植物隐性雌雄异株性系统的进化式样与机制研究提供理论资料。

关键词：隐性雌雄异株性表达性系统系统演化进化意义被子植物

化学修饰对雨生红球藻多糖体外抗肿瘤活性的影响

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食品科技 2024年第2期49卷 203-210页

作者：藏颖梁钟文刘松黄彩玉何珊李媚刘红全广西民族大学海洋与生物技术学院广西多糖材料与改性重点实验室广西南宁530007

为探究化学修饰对雨生红球藻多糖(Haematococcus pluvialis polysaccharide,HPP)体外抗肿瘤活性的影响,从雨生红球藻提取得到HPP,分别对其进行羧甲基化、硫酸化和乙酰化修饰,对获得的修饰多糖进行体外抗肿瘤活性的研究。对HPP进行羧甲... 详细信息

为探究化学修饰对雨生红球藻多糖(Haematococcus pluvialis polysaccharide,HPP)体外抗肿瘤活性的影响,从雨生红球藻提取得到HPP,分别对其进行羧甲基化、硫酸化和乙酰化修饰,对获得的修饰多糖进行体外抗肿瘤活性的研究。对HPP进行羧甲基化修饰得到C-HPP,其取代度为0.17;对HPP进行硫酸化修饰得到S-HPP,其取代度为0.22;对HPP进行乙酰化修饰得到A-HPP,其取代度为0.25。抗肿瘤试验结果表明,C-HPP、S-HPP和A-HPP体外抑制肝癌细胞hep G-2和宫颈癌细胞hela增殖的效果均优于HPP,其中乙酰化修饰对2种细胞增殖的抑制效果最好,IC_(50)分别为0.637 mg/mL和0.867 mg/mL。综上所述,对雨生红球藻多糖进行化学修饰可以提高其体外抑制肝癌细胞hep G-2和宫颈癌细胞hela增殖的活性,研究结果可为雨生红球藻多糖的进一步开发利用提供依据。

关键词：雨生红球藻多糖羧甲基化修饰硫酸化修饰乙酰化修饰抗肿瘤

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超声在脊柱外科应用的研究进展

中华骨科杂志 2024年第12期44卷 843-850页

作者：杨凯琪顾广飞贺石生同济大学附属第十人民医院脊柱外科上海200072

超声因具有无辐射、便携、价廉等优势而在普外科、妇产科等领域得到了广泛应用。但超声骨显像受限,因此在脊柱外科的应用并不多见。近年来超声技术与设备的发展拓宽了其在脊柱外科的应用场景。在诊断方面,肌骨超声能够清晰显示肌肉、肌... 详细信息

超声因具有无辐射、便携、价廉等优势而在普外科、妇产科等领域得到了广泛应用。但超声骨显像受限,因此在脊柱外科的应用并不多见。近年来超声技术与设备的发展拓宽了其在脊柱外科的应用场景。在诊断方面,肌骨超声能够清晰显示肌肉、肌腱、关节等组织的解剖结构,对脊柱疾病早期诊断具有重要意义;治疗方面,超声引导下脊柱源性疼痛介入治疗已较为成熟,包括选择性神经根阻滞、关节突关节阻滞等,显示出较高的准确率、安全性及疗效。超声辅助脊柱内镜手术置管应用的增加可减少术者及患者的辐射暴露;基于超声对椎弓根螺钉钉道完整性及钉道内壁与皮质骨距离的评估,研究者对其在脊柱椎弓根螺钉置入手术中的应用进行了进一步探索,开发了新型椎弓根探路器等,但目前对超声设备参数设置仍存在争议。此外,术中超声在脊柱肿瘤手术中可辅助定位肿瘤、评估切除范围以及在减压手术中评估减压效果和脊髓灌注状况。尽管超声在脊柱外科的应用前景广阔,但仍存在一些问题,如图像清晰度不高、分辨精度偏低、骨显像受限等。超声技术在脊柱外科的应用已展现出巨大的发展潜力,随着技术的进步和医生技能的提升,未来将在脊柱外科领域发挥更大的作用。

关键词：超声检查脊椎穿刺外科手术,计算机辅助脊柱疾病

Modulating selective interaction of NiOOH with Mg ions for high-performance aqueous batteries

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eScience 2024年第5期4卷 160-169页

作者： Bing he Ying Ling zhixun Wang Wenbin Gong Zhe Wang Yanting Liu Tianzhu Zhou Ting Xiong Shuai Wang Yonggang Wang Qingwen Li Qichong Zhang Lei Wei School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang Avenue 639798Singapore Key Laboratory of Multifunctional Nanomaterials and Smart Systems Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Department of Chemistry Fudan UniversityShanghai 200438China School of Physics and Energy Xuzhou University of TechnologyXuzhou 221018China

Aqueous Mg-ion batteries(AMIBs)featuring advantages of good safety,low cost,and high specific energy have been recognized as a promising energy-storage ***,the performance of AMIBs is consistently limited by sluggish diffusion kinetics and structural degradation of cathode materials arising from the strong electrostatic interactions between high-charge-density Mg2+and host ***,layered-structured NiOOH,as traditional cathodes for alkaline batteries,is initially demonstrated to realize proton-assisted Mg-(de)intercalation chemistry with a high discharge platform(0.57V)in neutral aqueous *** from the unique core/shell structure,the resulting NiOOH/CNT cathodes achieve a high capacity of 122.5 mAh g−1 and long cycle *** theoretical calculations reveal that the binding energy of hydrated Mg2+is higher than that of Mg2+with NiOOH,resulting in that Mg2+is easily intercalated/de-intercalated into/from *** from the freestanding design,the assembled fiber-shaped“rocking-chair”NaTi2(PO4)3//NiOOH AMIB shows a high energy density and satisfactory mechanical flexibility,which could be woven into a commercial fabric and power for fiber-shaped photoelectric sensors.

关键词： NiOOHAqueous electrolyte Mg-intercalation chemistry Rocking-chair Mg-ion batteries Fiber electronics

Multifunctional catalytic sites regulation of atomic-scale iridium on orthorhombic-CoSe_(2)for high efficiency dual-functional alkaline hydrogen evolution and organic degradation

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Journal of Energy Chemistry 2024年第5期92卷 271-281页

作者： Jingjing Huang Chenglin Zhong Yanjie Xia Jia Liu Guizhen Li Chao Yang Jiahong Wang Qian Wang Zhenbao Zhang Feng Yan Jianghua Wu Yu Deng Zhenjiang Zhou Xingchen he Paul K.Chu Woon-Ming Lau Xue-Feng Yu College of Chemistry and Chemical Engineering Linyi UniversityLinyi 276005ShandongChina Shenzhen Engineering Center for the Fabrication of Two-Dimensional Atomic Crystals Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina National Laboratory of Solid State Microstructures Jiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093JiangsuChina College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310058ZhejiangChina Department of Physics Department of Materials Science and EngineeringDepartment of Biomedical EngineeringCity University of Hong KongTat Chee AvenueKowloonHong KongChina

The earth-abundant and high-performance catalysts are crucial for commercial implementation of hydrogen evolution reaction(heR).herein,a multifunctional site strategy to construct excellent heR catalysts by incorporating iridium(Ir)ions on the atomic scale into orthorhombic-CoSe2(Ir-CoSe_(2))was *** hydrogen evolution activity in alkaline media such as a low overpotential of 48.7 mV at a current density of 10 mA cm^(-2)and better performance than commercial Pt/C catalysts at high current densities were found in the Ir-CoSe_(2) *** the experiments and theoretical calculations,it was revealed that Ir enabled CoSe_(2)to form multifunctional sites to synergistically catalyze alkaline heR by promoting the adsorption and dissociation of H_(2)O(Ir sites)and optimizing the binding energy for H^(*)on Co *** was noticeable that the electrolytic system comprising the Ir-CoSe_(2)electrode not only produced hydrogen efficiently via heR,but also degraded organic pollutants(Methylene blue).The cell voltage of the dual-function electrolytic system was 1.58 V at the benchmark current density of 50 mA cm^(-2),which was significantly lower than the conventional water splitting *** was indicated that this method was a novel strategy for designing advanced heR electrocatalysts by constructing multifunctional catalytic sites for hydrogen production and organic degradation.

关键词： Orthorhombic-CoSe_(2) Multifunctional sites design Hydrogen evolution reaction Synergistically catalyze Methylene blue oxidation

Research on remote intelligent control technology of throttling and back pressure in managed pressure drilling

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Petroleum 2021年第2期7卷 222-229页

作者： he Zhang Yongzhi Qiu Haibo liang Yunan Li Xiru Yuan School of Mechanical and Electrical Engineering Southwest Petroleum UniversityChengdu610500China

In order to reduce the non production time of drilling,improve the efficiency and safety of drilling,improve the economic effect of managed pressure drilling(MPD),and realize the intelligent control construction of digital *** on the pressure control in MPD,this paper analyzes the pressure control drilling system,takes the wellhead back pressure as the controlled parameter,calculates the mathematical model of the throttle valve according to the characteristics of the throttle valve,the basic parameters and boundary conditions of pressure control drilling,and puts forward an improved particle swarm Optimization PID neural network(IPSO-PIDNN)*** means of remote communication,VR technology can realize remote control of field control *** real-time control results of IPSO-PIDNN are compared with those of traditional PID neural network(PIDNN)and traditional Particle Swarm Optimization PID neural network(PSO-PIDNN).The results show that IPSO-PIDNN model has good self-learning characteristics,high optimization quality,high control accuracy,no overshoot,fast response and short regulation ***,the advanced automatic control of bottom hole pressure in the process of MPD is realized,which provides technical guarantee for the well control safety of MPD.

关键词： Managed pressure drilling(MPD) IPSO-PIDNN algorithm Throttling back pressure Intelligent control

Burden landscape of hepatobiliary and pancreatic cancers in Chinese young adults:30 years’overview and forecasted trends

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World Journal of Gastrointestinal Oncology 2024年第10期16卷 4177-4193页

作者： De-Sheng Chen Ze-Ping Chen Dong-Zi Zhu Lv-Xin Guan Qi Zhu Yi-Chao Lou Ze-Ping he Hao-Nan Chen Hong-Cheng Sun Department of General Surgery Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China Department of General Surgery Shanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Shenzhen Institute of Translational Medicine The First Affiliated Hospital of Shenzhen UniversityShenzhen 518035Guangdong ProvinceChina Department of General Surgery Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310016Zhejiang ProvinceChina

BACKGROUND hepatobiliary and pancreatic(HBP)cancers impose a considerable burden on young populations(aged 15 to 49 years),resulting in a substantial number of new cases and fatalities each *** young populations,the HBP cancers shows extensive variance worldwide and the updated data in China is *** To investigate the current status,trends,projections,and underlying risk factors of HBP cancers among young populations in *** The Global Burden of Disease Study 2019 provided data on the annual incidence,mortality,disability-adjusted life years(DALYs),age-standardized incidence rate(ASIR),mortality rate(ASMR),and DALYs rate(ASDR)of HBP cancers in young Chinese adults between 1990 and *** trends were assessed using estimated annual percentage change and hierarchical ***-specific mortality and DALYs caused by various risks were analyzed across China and other regions,with future trends until 2035 projected using the Bayesian age-period-cohort *** From 1990 to 2019,incident cases,deaths,DALYs,ASIR,ASMR,and ASDR for liver cancer(LC)in young Chinese individuals decreased,classified into'significant decrease'***,cases of gallbladder and biliary tract cancer and pancreatic cancer rose,categorized as either'significant increase'or'minor increase'*** contribution of risk factors to mortality and DALYs for HBP tumors increased to varying *** lifestyle behaviors,such as tobacco control,weight management,alcohol moderation,and drug avoidance,could lower HBP cancers ***,except for LC in females,which is likely to initially decline slightly and then rise,the forecasting model predicted that the ASIR and ASMR for all HPB cancers subtypes by gender will increase among young *** HBP cancers burden among young adults in China is expected to increase until 2035,necessitating lifestyle interventions and targeted treatment strategies to mitigate the public health impact of these

关键词： hepatobiliary and pancreatic cancers Burden landscape Young adults Projection China

Preliminary study of the electrospray DPE peculiarities from the liquid surface in the presence of the CSWs

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Plasma Science and Technology 2024年第5期26卷 110-120页

作者：贺伟国霍卫杰韩罗峰朱康武王锋王泽坤 School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444People’s Republic of China Shanghai Aerospace Electronic Technology Institute Shanghai 201109People’s Republic of China Shanghai Aerospace Control Technology Institute Shanghai 201109People’s Republic of China

The Ultrasonic Electric Propulsion(UEP)system is a cutting-edge propulsion technology that is mostly used on platforms for small satellites(less than 10 kg).The characteristics of droplet partial emissions(DPEs)in the UEP system are investigated using a high-speed imaging technique(an ultra-high speed camera(NAC HX-6)and a long-distance microscope)in this *** experiments demonstrate that there are a few partial emission modes,including left-side emission,double-side emission,and right-side emission,that are present in the droplet emission process of the UEP *** modes are primarily caused by the partial formation of capillary standing waves(CSWs)on the emission surface of the ultrasonic *** emission rate for single-and double-sided emissions varies at different times,indicating that there are different CSWs engaged in droplet emission due to variations in the liquid film thickness and charge state of the liquid ***,as the droplets emit continuously,a raised area on the emission surface appears,with several droplets emitting there as a result of charge ***,photos of the CSWs with emitting droplets are obtained,which highlights the CSWs'distinctive wave morphology.

关键词： ultrasonic electric propulsion system microsatellite high-speed imaging technique droplet partial emissions electric field

庐山地区晚中生代深源岩浆与浅表构造变形的相互作用

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科学通报 2024年第2期69卷 301-316页

作者：莫佳君徐义刚何斌中国科学院广州地球化学研究所同位素地球化学国家重点实验室广州510640 中国科学院深地科学卓越研究中心广州510640 中国科学院大学地球与行星科学学院北京100049

本文在对庐山地质构造细致解剖的基础上,根据研究区岩浆岩的同位素年代学、锆石Hf同位素和元素地球化学特征,提出了研究区基性岩浆的高分异作用;结合对变质作用和构造变形时间的约束,揭示了研究区晚中生代深源岩浆演化与逆冲推覆构造和... 详细信息

本文在对庐山地质构造细致解剖的基础上,根据研究区岩浆岩的同位素年代学、锆石Hf同位素和元素地球化学特征,提出了研究区基性岩浆的高分异作用;结合对变质作用和构造变形时间的约束,揭示了研究区晚中生代深源岩浆演化与逆冲推覆构造和片麻岩穹隆的共生关系.庐山地区晚中生代构造格架主要为飞来峰构造和星子片麻岩穹隆,两者在时空上存在一致性.星子片麻岩穹隆中心发育大量晚中生代岩浆岩,岩石类型从基性岩脉到高分异花岗岩,包括斜长角闪片麻岩、角闪石岩、黑云母角闪闪长岩、石英闪长岩、黑云母(二长)花岗岩、白岗岩和伟晶岩,这些侵入岩的锆石年龄在误差范围内一致(141±2 Ma).不同类型岩石的锆石εHf(t)值为−10.5~+2.2,推测白岗岩和伟晶岩是基性岩浆高分异作用的结果.岩浆侵位和演化明显受到北东向逆冲推覆构造的控制,自南西向北东,岩浆的演化程度逐渐增强.本文认为,由岩浆热弱化地壳强度是庐山地区发育逆冲推覆构造的关键条件.与此同时,推覆构造和韧性剪切带隔热作用是基性岩浆发生高程度分异的重要因素.因此,庐山地区晚中生代地质演化是深源岩浆与浅表构造变形相互作用的一个实例,代表了板内强烈变形和造山运动的一种方式,与早白垩世太平洋板块俯冲作用密切关联.

关键词：庐山晚中生代逆冲推覆构造片麻岩穹隆岩浆高分异演化深源岩浆与浅表构造