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硫酸铜胁迫对小麦种子淀粉分解、抗氧化特性及幼苗生长的影响

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麦类作物学报 2025年第1期45卷 112-120页

作者：许世初梁丹丹邹帆屠钰欢郭天荣王海莫亿伟绍兴文理学院生命与环境科学学院浙江绍兴312000

为了揭示Cu^(2+)胁迫对小麦种子萌发和幼苗生长的毒害机制,采用水培法,在1/100的MS培养基里加入不同剂量的CuSO_(4)[0(CK)、30、60和90 mg·kg^(-1)],对小麦进行浸种和幼苗培养,测定小麦种子、幼叶及种子根的生理指标和生长参数。结果表... 详细信息

为了揭示Cu^(2+)胁迫对小麦种子萌发和幼苗生长的毒害机制,采用水培法,在1/100的MS培养基里加入不同剂量的CuSO_(4)[0(CK)、30、60和90 mg·kg^(-1)],对小麦进行浸种和幼苗培养,测定小麦种子、幼叶及种子根的生理指标和生长参数。结果表明,与CK相比,CuSO_(4)胁迫下小麦种子萌发过程中的淀粉酶活性、淀粉粒分解速率、可溶性总糖、可溶性蛋白和氨基酸含量、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性均显著降低(P<0.05),过氧化物酶(POD)活性显著增加。种子萌发后,种子根内SOD、CAT和POD活性均随CuSO_(4)浓度的增加而增加,但呼吸脱氢酶活性、超氧阴离子(O_(2)^(-·))含量和H_(2) O_(2)荧光强度均显著下降。小麦幼苗在CuSO_(4)胁迫下Cu主要积累于种子根内,导致根尖有丝分裂明显受阻,使株高、根长、种子根数量和植株干重均显著下降。综上,Cu^(2+)对小麦幼苗的毒害表现出剂量依赖性效应;Cu^(2+)通过降低小麦种子萌发阶段的淀粉酶活性抑制淀粉分解,引起氧化损伤,最终阻碍幼苗生长。

关键词：小麦种子硫酸铜抗氧化特性

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美英澳三边安全伙伴关系扩员:联盟升级还是联盟分歧

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东北亚学刊 2025年第1期 90-109,148页

作者：李途南京大学国际关系学院南京210023 中国南海研究协同创新中心

美英澳三边安全伙伴关系(AUKUS)扩员是美国主导下的联盟转型的产物,符合美国以小多边方式打造遏华阵营的目标。其主要目的是利用盟国的技术创新优势,打造国防技术共享联盟,减少美国维持联盟体系的成本。日本的价值是美国考虑接纳其加入... 详细信息

美英澳三边安全伙伴关系(AUKUS)扩员是美国主导下的联盟转型的产物,符合美国以小多边方式打造遏华阵营的目标。其主要目的是利用盟国的技术创新优势,打造国防技术共享联盟,减少美国维持联盟体系的成本。日本的价值是美国考虑接纳其加入的主要原因。当前扩员并非正式成员资格的拓展,AUKUS不是日本加入就要更名为“JAUKUS”。与美国积极推动日本加入相比,澳大利亚同意日本加入AUKUS第二支柱实属无奈,联盟分歧已然显现。即使日本加入后,AUKUS扩员仍然面临着小多边的效率难题、成员国的能力缺口、美国承诺的可信度等诸多挑战。

关键词：美英澳三边安全伙伴关系 AUKUS扩员第二支柱小多边机制

Comparison and application of different empirical correlations for estimating the hydrate safety margin of oil-based drilling fluids containing ethylene glycol

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Journal of Natural Gas Chemistry 2011年第1期20卷 25-33页

作者： Fulong Ning ling Zhang Guosheng Jiang Yunzhong tu Xiang W u Yibing Yu FacultyofEngineering ChinaUniversityofGeosciencesWuhan430074HubeiChina DepartmentofChemistry NorwegianUniversityofScienceandTechnologyTrondheimNO-7491Norway NationalLaboratoryonScientificDrilling ChinaUniversityofGeosciencesatBeijingBeijing100083China

As the oil and gas industries continue to increase their activity in deep water, gas hydrate hazards will become more serious and challenging, both at present and in the future. Accurate predictions of the hydrate-free zone and the suitable addition of salts and/or alcohols in preparing drilling fluids are particularly important both in preventing hydrate problems and decreasing the cost of drilling operations. In this paper, we compared several empirical correlations commonly used to estimate the hydrate inhibition effect of aqueous organic and electrolyte solutions using experiments with ethylene glycol （EG） as a hydrate inhibitor. The results show that the Najibi et al. correlation （for single and mixed thermodynamic inhibitors） and the Ostergaard et al. empirical correlation （for single thermodynamic inhibitors） are suitable for estimating the hydrate safety margin of oil-based drilling fluids （OBDFs） in the presence of thermodynamic hydrate inhibitors. According to the two correlations, the OBDF, composed of 1.6 L vaporizing oil, 2% emulsifying agent, 1% organobentonite, 0.5% SP-1, 1% LP-1, 10% water and 40% EG, can be safely used at a water depth of up to 1900 m. However, for more accurate predictions for drilling fluids, the effects of the solid phase, especially bentonite, on hydrate inhibition need to be considered and included in the application of these two empirical correlations.

关键词： oil-based drilling fluid gas hydrates ethylene glycol inhibition prediction

Hydrogen storage properties of non stoichiometric AB_2-type metal hydride

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中国有色金属学会会刊：英文版 2000年第3期10卷 289-293页

作者： tu hai ling(屠海令), HUANG Zhuo(黄倬), GAO Hui long(高会龙), ZHAN Feng(詹锋) Beijing General Research Institute for Non ferrous Metals, Beijing 100088, P.R.China Beijing Gen Res Inst Nonferrous Met Beijing 100088 Peoples R China

Hydrogen storage properties of non stoichiometric AB 2 type alloys, Ti 0.8 Zr 0.2 (MnCrVFe) 2- x ( x =0, 0.1, 0.2, 0.3), have been studied. The results show that the structures of the substoichiometric alloys can be described using the replacement model, that is, some A side atoms occupy the primary B side atom positions. The equilibrium pressures of the alloys decrease gradually and the hysteresis effect between hydriding and dehydriding process decreases with the increase of x value. The free energy change (Δ G ) between hydriding and dehydriding process has a significant effect on the hysteresis of the alloys. The p c t plateau region becomes narrow and the reversible hydrogen capacity decreases with the increase of x value ( x >0.1), although the hydrogen absorption capacity increases. The alloy with x =0.1 shows the optimum hydrogen storage properties.

关键词： hydrogen storage property substoichiometric alloy hysteresis effect

RESULTS OF RECENT StuDIES ON HEPATITIS B VIRUS INFECTION IN RURAL AREAS IN BEIJING

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中华医学杂志(英文版) 1990年第1期103卷 87-88页

作者： Jiang Yu-tu Wang hai-tao Yun Shu-rong 100850

Sir: In recent years, our institute, the Institute of Microbiology and Epidemiology,the Academy of Military Medical Sciences,has carried out several studies on the epidemiology of hepatitis B virus infection in the suburbs of Beijing. The results showed some facts, which have not been published in the medical literature:

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Thioredoxin pathway regulated live-cell synthesis of CdSe quantum dots in Saccharomyces cerevisiae

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Science China Chemistry 2024年第11期67卷 3851-3860页

作者： Xu Li Cai-Qin Wu Jia-Wei tu Juan Kong ling-ling Yang Zhi-Xiong Xie Dai-Wen Pang College of Chemistry and Molecular Sciences The Institute for Advanced StudiesCollege of Life SciencesWuhan UniversityWuhan 430072China Research Center for Analytical Sciences College of ChemistryState Key Laboratory of Medicinal Chemical BiologyTianjin Key Laboratory of Biosensing and Molecular RecognitionFrontiers Science Center for New Organic MatterFrontiers Science Center for Cell Responsesand Haihe Laboratory of Sustainable Chemical TransformationsNankai UniversityTianjin 300071China

Currently, the application of synthetic biology to artificially manipulate and utilize organisms for the synthesis of desired products such as nanomaterials with excellent fluorescence properties is attracting considerable attention. However, it is still difficult to obtain designed products efficiently due to insufficient knowledge of the biosynthetic mechanisms. The thioredoxin(TRX) and glutathione(GSH) pathways are generally conserved thiol-reductase systems that protect organisms from oxidative stress and are involved in selenium(Se) metabolism. In this study, we revealed the pivotal role of cytoplasmic TRX pathway in regulating the metabolism of Na_(2)SeO_(3) during the live-cell synthesis of cadmium-selenium quantum dots(Cd Se QDs) in Saccharomyces cerevisiae by regulating the expression level of genes related to TRX pathway and measuring the intracellular content of selenocysteine(Se Cys). The determination of Se Cys metabolism in yeast with GSH pathway-related genes deleted demonstrated that the TRX pathway played a more significant role in Se Cys metabolism than GSH pathway. A 6.4-fold enhancement in the synthetic yield of Cd Se QDs was achieved through the overexpression of TRX pathway-related genes,improvement of synthetic procedure, and supplementation of GSH based on the understanding of biological *** the mechanism of CdSe QDs live-cell synthesis facilitates the precise manipulation of biological processes for the synthesis of inorganic nanomaterials.

关键词： thioredoxin glutathione quantum dot live-cell synthesis selenium metabolism Saccharomyces cerevisiae

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Separated root tip formation associated with a fractured tubercle of dens evaginatus: A case report

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World Journal of Clinical Cases 2021年第12期9卷 2944-2950页

作者： Zhi-Fang Wu ling-Jiao Lu hai-Yan Zheng Yan tu Ying Shi Zi-Huai Zhou Lin-Xian Fang Bai-Ping Fu Department of Pediatric Dentistry The Affiliated Hospital of StomatologySchool of StomatologyZhejiang University School of MedicineKey Laboratory of Oral Biomedical Research of Zhejiang ProvinceHangzhou 310006Zhejiang ProvinceChina Department of Prosthodontics The Affiliated Hospital of StomatologySchool of StomatologyZhejiang University School of MedicineKey Laboratory of Oral Biomedical Research of Zhejiang ProvinceHangzhou 310006Zhejiang ProvinceChina Department of Endodontics The Affiliated Hospital of StomatologySchool of StomatologyZhejiang University School of MedicineKey Laboratory of Oral Biomedical Research of Zhejiang ProvinceHangzhou 310006Zhejiang ProvinceChina

BACKGROUND Several previous studies have reported an unusual root formation in which a fractured apical fragment of an immature root continued to develop independent of the main root after trauma to an immature *** date,there have been only rare reports of the continuing apical formation of the fractured root associated with dens evaginatus(DE).This paper presents a case of a separated root tip formation associated with a fractured tubercle of *** SUMMARY An 11-year-old boy was referred for gingival sinus on the buccal side of the right mandibular second premolar(tooth#45).Clinically,tooth#45 was free of caries,but there was a sign of a fractured tubercle of DE on the occlusal *** showed that the root canal of tooth#45 was widely radiolucent.A separated root apex was found apically under the main root and was nearly completely formed with an apical orifice at the apical ***#45 was diagnosed as tubular fracture of DE with chronic apical periodontitis.A revascularization technique was recommended to treat the *** 3-mo and 1-yr follow-up,the patient remained *** radiography revealed that the separated root tip distally drifted with closure of the ***,the root length and thickness of the main root did not *** Clinicians should be aware that even if tubercle of DE is fractured in an immature tooth,the root tip may be separated from the main root and completely formed.

关键词： Separated root tip Dens evaginatus tubercle fracture Young permanent tooth Revascularization Case report

县域医共体改革:构建整合型医疗卫生服务体系的中国方案

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治理研究 2025年第1期41卷 81-90,159页

作者：涂怡欣郁建兴浙江大学公共管理学院浙江工商大学

“起源于安徽,发展于山西,拓展于浙江”的县域医共体改革,是中国2009年实施新医改后最重要的强基层政策工具。在地方探索与顶层设计的互动中,县域医共体改革逐渐成为构建整合型医疗卫生服务体系的中国方案。县域医共体改革在提升基层卫... 详细信息

“起源于安徽,发展于山西,拓展于浙江”的县域医共体改革,是中国2009年实施新医改后最重要的强基层政策工具。在地方探索与顶层设计的互动中,县域医共体改革逐渐成为构建整合型医疗卫生服务体系的中国方案。县域医共体改革在提升基层卫生服务能力方面发挥了积极效应,为国际整合医疗卫生服务理论与实践提供了中国经验和中国智慧。县域医共体改革目前仍然存在局限性,主要源于改革的不彻底,而这恰恰指明了县域医共体下一步改革的重点与方向,即以医保支付方式为核心,驱动县域医疗共同体向以人民健康为中心的健康共同体转型。

关键词：整合型医疗卫生服务体系县域医共体基层卫生服务能力

Boosting High-Rate Zinc-Storage Performance by the Rational Design of Mn_(2)O_(3) Nanoporous Architecture Cathode

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Nano-Micro Letters 2020年第1期12卷 195-207页

作者： Danyang Feng tu‑Nan Gao ling Zhang Bingkun Guo Shuyan Song Zhen‑An Qiao Sheng Dai State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012JilinPeople’s Republic of China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012JilinPeople’s Republic of China Materials Genome Institute Shanghai UniversityShanghai 200444People’s Republic of China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022People’s Republic of China Chemical Sciences Division Oak Ridge National LaboratoryOak RidgeTN 37831USA

Manganese oxides are regarded as one of the most promising cathode materials in rechargeable aqueous Zn-ion batteries(ZIBs)because of the low price and high ***,the practical application of Mn2O3 in ZIBs is still plagued by the low specific capacity and poor rate ***,highly crystalline Mn2O3 materials with interconnected mesostructures and controllable pore sizes are obtained via a ligand-assisted self-assembly process and used as high-performance electrode materials for reversible aqueous *** coordination degree between Mn2+and citric acid ligand plays a crucial role in the formation of the mesostructure,and the pore sizes can be easily tuned from 3.2 to 7.3 *** to the unique feature of nanoporous architectures,excellent zinc-storage performance can be achieved in ZIBs during charge/discharge *** Mn2O3 electrode exhibits high reversible capacity(233 mAh g−1 at 0.3 A g−1),superior rate capability(162 mAh g−1 retains at 3.08 A g−1)and remarkable cycling durability over 3000 cycles at a high current rate of 3.08 A g−***,the corresponding electrode reaction mechanism is studied in depth according to a series of analytical *** results suggest that rational design of the nanoporous architecture for electrode materials can effectively improve the battery performance.

关键词： Porous Mn_(2)O_(3) High-rate capability Zn-ion battery Cathode material Zn-storage mechanism