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Relationship between Seed Priming Mediated Seedling Vigor and Yield Performance of Spring Wheat
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作者 Md.Parvez Anwar Masuma Akhter +5 位作者 Sharmin Aktar Sinthia Afsana Kheya A.K.M.Mominul Islam Sabina Yeasmin Ahmed Khairul Hasan Md.Harun Or Rashid 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第6期1159-1177,共19页
Seed priming is a pre-germinated technique that can enhance seed germination percentage,faster and synchro-nized germination,better seedling growth,and yield under stress conditions.To ascertain the most effective see... Seed priming is a pre-germinated technique that can enhance seed germination percentage,faster and synchro-nized germination,better seedling growth,and yield under stress conditions.To ascertain the most effective seed priming method that would ensure the potential yield of wheat in Bangladesh,two experiments were carried out from December 2021 to March 2022 at the Department of Agronomy,Bangladesh Agricultural University.Two wheat varieties namely BARI Gom-28 and BWMRI Gom-1 were subjected to a range of priming chemicals in both lab and pot tests.These compounds included the following:control(no priming),hydropriming(distilled water),10000 ppm KNO_(3),15000 ppm KNO_(3),40000 ppm Mannitol,60000 ppm Mannitol,10000 ppm NaCl,20000 ppm NaCl,100 ppm PEG,150 ppm PEG,500 ppm NaOCl,1000 ppm NaOCl,10000 ppm CaCl_(2),20000 ppm CaCl_(2),10000 ppm KCl and 20000 ppm KCl.A complete randomized design(CRD)with three repli-cations was used to set up the experiments.The results showed that BARI Gom-28 and BWMRI Gom-1 responded best to KCl priming in terms of rapid seed germination and strong seedling development.On the other hand,the best priming agents for plant growth and productivity turned out to be CaCl_(2) and KCL.The results of this study support the possibility of using seed priming as a technique to improve wheat plant development and output by raising seed emergence and survival rates. 展开更多
关键词 priming seedling percentage GERMINATION growth YIELD WHEAT
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Use of priming strategies to advance the clinical application of mesenchymal stromal/stem cell-based therapy
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作者 Vitale Miceli 《World Journal of Stem Cells》 SCIE 2024年第1期7-18,共12页
Mesenchymal stromal/stem cells(MSCs)have garnered significant attention in the field of regenerative medicine due to their remarkable therapeutic potential.MSCs play a pivotal role in maintaining tissue homeostasis an... Mesenchymal stromal/stem cells(MSCs)have garnered significant attention in the field of regenerative medicine due to their remarkable therapeutic potential.MSCs play a pivotal role in maintaining tissue homeostasis and possess diverse functions in tissue repair and recovery in various organs.These cells are charac-terized by easy accessibility,few ethical concerns,and adaptability to in vitro cultures,making them a valuable resource for cell therapy in several clinical conditions.Over the years,it has been shown that the true therapeutic power of MSCs lies not in cell engraftment and replacement but in their ability to produce critical paracrine factors,including cytokines,growth factors,and exosomes(EXOs),which modulate the tissue microenvironment and facilitate repair and regeneration processes.Consequently,MSC-derived products,such as condi-tioned media and EXOs,are now being extensively evaluated for their potential medical applications,offering advantages over the long-term use of whole MSCs.However,the efficacy of MSC-based treatments varies in clinical trials due to both intrinsic differences resulting from the choice of diverse cell sources and non-standardized production methods.To address these concerns and to enhance MSC therapeutic potential,researchers have explored many priming strategies,including exposure to inflammatory molecules,hypoxic conditions,and three-dimensional culture techniques.These approaches have optimized MSC secretion of functional factors,empowering them with enhanced immunomodulatory,angiogenic,and regenerative properties tailored to specific medical conditions.In fact,various priming strategies show promise in the treatment of numerous diseases,from immune-related disorders to acute injuries and cancer.Currently,in order to exploit the full therapeutic potential of MSC therapy,the most important challenge is to optimize the modulation of MSCs to obtain adapted cell therapy for specific clinical disorders.In other words,to unlock the complete potential of MSCs in regenerative medicine,it is crucial to identify the most suitable tissue source and develop in vitro manipulation protocols specific to the type of disease being treated. 展开更多
关键词 Mesenchymal stromal/stem cells Therapeutic properties Paracrine effects Cell priming Cell-free therapies Regenerative medicine
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Different priming strategies improve distinct therapeutic capabilities of mesenchymal stromal/stem cells:Potential implications for their clinical use 被引量:1
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作者 Vitale Miceli Giovanni Zito +4 位作者 Matteo Bulati Alessia Gallo Rosalia Busà Gioacchin Iannolo Pier Giulio Conaldi 《World Journal of Stem Cells》 SCIE 2023年第5期400-420,共21页
Mesenchymal stromal/stem cells(MSCs)have shown significant therapeutic potential,and have therefore been extensively investigated in preclinical studies of regenerative medicine.However,while MSCs have been shown to b... Mesenchymal stromal/stem cells(MSCs)have shown significant therapeutic potential,and have therefore been extensively investigated in preclinical studies of regenerative medicine.However,while MSCs have been shown to be safe as a cellular treatment,they have usually been therapeutically ineffective in human diseases.In fact,in many clinical trials it has been shown that MSCs have moderate or poor efficacy.This inefficacy appears to be ascribable primarily to the heterogeneity of MSCs.Recently,specific priming strategies have been used to improve the therapeutic properties of MSCs.In this review,we explore the literature on the principal priming approaches used to enhance the preclinical inefficacy of MSCs.We found that different priming strategies have been used to direct the therapeutic effects of MSCs toward specific pathological processes.Particularly,while hypoxic priming can be used primarily for the treatment of acute diseases,inflammatory cytokines can be used mainly to prime MSCs in order to treat chronic immune-related disorders.The shift in approach from regeneration to inflammation implies,in MSCs,a shift in the production of functional factors that stimulate regenerative or anti-inflammatory pathways.The opportunity to fine-tune the therapeutic properties of MSCs through different priming strategies could conceivably pave the way for optimizing their therapeutic potential. 展开更多
关键词 Mesenchymal stromal/stem cells Mesenchymal stromal/stem cell therapeutic properties Mesenchymal stromal/stem cell paracrine effects Mesenchymal stromal/stem cell priming Pro-inflammatory priming Hypoxic priming 3D culture priming
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Seed Priming Improves Enzymatic and Biochemical Performances of Rice During Seed Germination under Low and High Temperatures
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作者 Salar MONAJJEM Elias SOLTANI +4 位作者 Ebrahim ZAINALI Masoud ESFAHANI Farshid GHADERI-FAR Maryam HOSSEINI CHALESHTORI Atefeh REZAEI 《Rice science》 SCIE CSCD 2023年第4期335-347,I0024-I0027,共17页
As an abiotic stress,adverse germination temperatures cause serious disruptions in physiological and biochemical processes involved in seed germination.Using a factorial experiment,we examined the effects of different... As an abiotic stress,adverse germination temperatures cause serious disruptions in physiological and biochemical processes involved in seed germination.Using a factorial experiment,we examined the effects of different seed priming treatments on enzymatic and biochemical performances of rice seed germination under different temperatures.Each of the rice genotypes(Hashemi,Sadry-domsefid,IRON-70-7053-7 and NORIN-22)was primed with hydro-hardening,KCl,CaCl2 and ascorbic acid(AsA)and without a priming agent as a control at low(15℃),optimum(25℃)and high(35℃)germination temperatures.The results showed that the enzymatic and biochemical performances of all the rice genotypes were affected by the seed priming agents,especially under the low germination temperature.At 15℃,seed priming with AsA was found to be the best agent for the activities of amylase,α-amylase,catalase(CAT),peroxidase(POX),ascorbate peroxidase(APOX)and superoxide dismutase(SOD)as well as the content of soluble sugars in the NORIN-22 genotype,and for protease activity and soluble protein content in the IRON-70-7053-7 genotype.SOD at the low germination temperature and CAT,POX and protease at the optimum and high germination temperatures were the most important enzymes in occurrence of germination potential in terms of seedling length,vigor index,normal seedling rate and germination rate.Under the priming agents,the highest changes in normal seedling rate were observed at the low and optimum germination temperatures by AsA priming in the Hashemi and NORIN-22 genotypes,and at the high germination temperature under KCl priming in the Hashemi genotype. 展开更多
关键词 antioxidant activity biochemical performance germination temperature RICE seed priming
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Mepiquat chloride priming confers the ability of cotton seed to tolerate salt by promoting ABA-operated GABA signaling control of the ascorbate–glutathione cycle
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作者 QI Qian WANG Ning +9 位作者 RUAN Sijia MUHAMMAD Noor ZHANG Hengheng SHI Jianbin DONG Qiang XU Qinghua SONG Meizhen YAN Gentu ZHANG Xiling WANG Xiangru 《Journal of Cotton Research》 CAS 2023年第4期288-305,共18页
Background Ensuring that seeds germinate and emerge normally is a prerequisite for cotton production,esp.in areas with salinized soil.Priming with mepiquat chloride(MC)can promote seed germination and root growth unde... Background Ensuring that seeds germinate and emerge normally is a prerequisite for cotton production,esp.in areas with salinized soil.Priming with mepiquat chloride(MC)can promote seed germination and root growth under salt stress,but its mechanism has not been fully elucidated.In this study,physiological and biochemical experiments revealed that MC-priming promotes the tolerance of cotton seeds to salt stress by increasing the ability of antioxidant enzymes related to the ascorbate-glutathione(AsA-GSH)cycle to scavenge reactive oxygen species(ROS).Results Results revealed that treatment with inhibitors of abscisic acid(ABA)and γ-aminobutyric acid(GABA)biosynthesis reduced the positive effects of MC-priming.Similarly,MC-priming increased the contents of ABA and GABA under salt stress by stimulating the expression levels of GhNCED2 and GhGAD4 and the activity of calmodulin-binding(CML)glutamate decarboxylase(GAD).Further analysis showed that an inhibitor of ABA synthesis reduced the positive impacts of MC-priming on the content of GABA under salt stress,but the content of ABA was not affected by the GABA synthesis inhibitor.Furthermore,a multi-omics analysis revealed that MC-priming increased the abundance and phosphorylation levels of the proteins related to ABA signaling,CML,and Ca^(2+)channels/transporters in the MC-primed treatments,which resulted in increased oscillations in Ca^(2+)in the MC-primed cotton seeds under salt stress.Conclusion In summary,these results demonstrate that MC-mediated ABA signaling operates upstream of the GABA synthesis generated by GAD by activating the oscillations of Ca^(2+)and then enhancing activity of the AsA-GSH cycle,which ensures that cotton seeds are tolerant to salt stress. 展开更多
关键词 Seed priming Salinity stress ABA signaling γ-aminobutyric acid ROS scavenging Mepiquat chloride
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PRiME HLB前处理技术联合超高效液相色谱-三重四极杆质谱系统检测水产品中17种磺胺类药物残留 被引量:2
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作者 余海芬 徐桦 +5 位作者 吴真善 包蔚 朱晓芸 何锴 黄忠 战涛 《现代食品》 2024年第1期213-215,224,共4页
使用通过型固相萃取小柱PRi ME HLB处理水产品样品,建立了一种水产品中17种磺胺类药物的简单、快速的筛选分析方法。水产品样品经80%乙腈水溶液(含0.2%甲酸)提取,过PRi ME HLB固相萃取柱净化,浓缩后经C_(18)色谱柱梯度洗脱分离,超高效... 使用通过型固相萃取小柱PRi ME HLB处理水产品样品,建立了一种水产品中17种磺胺类药物的简单、快速的筛选分析方法。水产品样品经80%乙腈水溶液(含0.2%甲酸)提取,过PRi ME HLB固相萃取柱净化,浓缩后经C_(18)色谱柱梯度洗脱分离,超高效液相色谱-三重四极杆质谱系统进行定量分析。结果表明,17种磺胺类药物在1.0~50.0 ng·mL^(-1)线性关系良好,相关系数R^(2)>0.99;该方法检出限为2μg·kg^(-1);添加浓度为10μg·kg^(-1)时方法回收率在71.3%~118.4%,RSD值均小于20%。 展开更多
关键词 磺胺 水产品 PRiME HLB固相萃取小柱
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Effect of priming on the germination of Peltophorum dubium seeds under water stress 被引量:3
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作者 张万里 李雷鸿 祖元刚 《Journal of Forestry Research》 CAS CSCD 2004年第4期287-290,共4页
Peltophorum dubium seeds provided by Anhembi, SP were scarified in 98% H2SO4 for 15 min to overcome mechani-cal dormancy. Seeds were primed in solutions of 0.2% Captan at 10 C and 27C, PEG 6000 -1.0 MPa at 10C and 27... Peltophorum dubium seeds provided by Anhembi, SP were scarified in 98% H2SO4 for 15 min to overcome mechani-cal dormancy. Seeds were primed in solutions of 0.2% Captan at 10 C and 27C, PEG 6000 -1.0 MPa at 10C and 27C, 0.5 mol KNO3, 0.75 Mol KNO3, 1.0 Mol KNO3. Eight treatments including the primed seeds and nonprimed seeds, five replicates with 100 seeds for each treatment, were set to 15-cm-Petri dish with double filter paper moistened with testing solution PEG in refrigerator at 27C. For the experiments of all the groups, osmotic potential were 0.0, -0.2, -0.4, -0.6, -0.8, -1.0, -1.2, and -1.4 MPa. P. dubium seeds were also set to water stress experiment in rolled paper with PEG solutions from 0.0 to -1.0 M Pa. Germination percentage decreased with the increase of PEG concentration. Control group had a better germination percentage than other groups. Germination hardly occurred in PEG -1.4 MPa. 展开更多
关键词 priming Osmotic potential GERMINATION Seeds Peltophorum dubium
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引导编辑技术的研究进展及应用 被引量:1
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作者 邱梅玉 张雪梅 +1 位作者 张宁 刘明军 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第4期1345-1355,共11页
以CRISPR/Cas9为基础的引导编辑系统是新开发出的一种基因编辑技术,可以精确实现12种碱基的互换、插入和缺失,并且不需要产生双链断裂和引入外源供体DNA。本文从基因编辑的发展、引导编辑系统的原理、特点、优化、脱靶效应、在动植物和... 以CRISPR/Cas9为基础的引导编辑系统是新开发出的一种基因编辑技术,可以精确实现12种碱基的互换、插入和缺失,并且不需要产生双链断裂和引入外源供体DNA。本文从基因编辑的发展、引导编辑系统的原理、特点、优化、脱靶效应、在动植物和基因治疗研究中的应用、引导编辑系统的设计等几方面进行综述,为促进相关领域的科研工作者了解引导编辑系统及进一步利用引导编辑系统在动植物科学基础研究和育种方面的应用提供指导。 展开更多
关键词 CRISPR/Cas9 引导编辑(prime editing PE) pegRNA 应用研究
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基于虚拟现实的船舶航行复杂周围环境图像三维仿真
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作者 张连慧 《舰船科学技术》 北大核心 2024年第4期166-169,共4页
为提升船舶在复杂航行环境中的安全,提出基于虚拟现实的船舶航行复杂周围环境图像三维仿真方法。该方法使用虚拟现实技术中的Vega Prime虚拟现实开发工具,依据海洋、船舶相关数据与图像,使用Crertor工具建立flt静态三维模型库,从该模型... 为提升船舶在复杂航行环境中的安全,提出基于虚拟现实的船舶航行复杂周围环境图像三维仿真方法。该方法使用虚拟现实技术中的Vega Prime虚拟现实开发工具,依据海洋、船舶相关数据与图像,使用Crertor工具建立flt静态三维模型库,从该模型库内导出船舶三维模型所需数据后,使用Vega Prime虚拟现实开发工具的LynXPrime图形界面,对船舶航行复杂周围环境的水体、海浪等进行建模并进行纹理制作后,再通过实时驱动、视景仿真驱动以及仿真交互程序运行,实现船舶航行复杂周围环境图像三维仿真模型的交互。实验结果表明,该方法可有效对船舶航行复杂周围环境的洋流流向、流速、海水温度进行三维仿真。同时也可对船舶航行环境内其他船舶进行红外视景可视化,且应用效果较佳。 展开更多
关键词 虚拟现实 船舶航行 环境图像 三维仿真 Vega Prime
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Development and Therapeutic Applications of Precise Gene Editing Technology
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作者 ZHANG Yi-Meng YANG Xiao +1 位作者 WANG Jian LI Zhen-Hua 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2024年第10期2637-2647,共11页
The advent of gene editing represents one of the most transformative breakthroughs in life science,making genome manipulation more accessible than ever before.While traditional CRISPR/Cas-based gene editing,which invo... The advent of gene editing represents one of the most transformative breakthroughs in life science,making genome manipulation more accessible than ever before.While traditional CRISPR/Cas-based gene editing,which involves double-strand DNA breaks(DSBs),excels at gene disruption,it is less effective for accurate gene modification.The limitation arises because DSBs are primarily repaired via non-homologous end joining(NHEJ),which tends to introduce indels at the break site.While homology directed repair(HDR)can achieve precise editing when a donor DNA template is provided,the reliance on DSBs often results in unintended genome damage.HDR is restricted to specific cell cycle phases,limiting its application.Currently,gene editing has evolved to unprecedented levels of precision without relying on DSB and HDR.The development of innovative systems,such as base editing,prime editing,and CRISPR-associated transposases(CASTs),now allow for precise editing ranging from single nucleotides to large DNA fragments.Base editors(BEs)enable the direct conversion of one nucleotide to another,and prime editors(PEs)further expand gene editing capabilities by allowing for the insertion,deletion,or alteration of small DNA fragments.The CAST system,a recent innovation,allows for the precise insertion of large DNA fragments at specific genomic locations.In recent years,the optimization of these precise gene editing tools has led to significant improvements in editing efficiency,specificity,and versatility,with advancements such as the creation of base editors for nucleotide transversions,enhanced prime editing systems for more efficient and precise modifications,and refined CAST systems for targeted large DNA insertions,expanding the range of applications for these tools.Concurrently,these advances are complemented by significant improvements in in vivo delivery methods,which have paved the way for therapeutic application of precise gene editing tools.Effective delivery systems are critical for the success of gene therapies,and recent developments in both viral and non-viral vectors have improved the efficiency and safety of gene editing.For instance,adeno-associated viruses(AAVs)are widely used due to their high transfection efficiency and low immunogenicity,though challenges such as limited cargo capacity and potential for immune responses remain.Non-viral delivery systems,including lipid nanoparticles(LNPs),offer an alternative with lower immunogenicity and higher payload capacity,although their transfection efficiency can be lower.The therapeutic potential of these precise gene editing technologies is vast,particularly in treating genetic disorders.Preclinical studies have demonstrated the effectiveness of base editing in correcting genetic mutations responsible for diseases such as cardiomyopathy,liver disease,and hereditary hearing loss.These technologies promise to treat symptoms and potentially cure the underlying genetic causes of these conditions.Meanwhile,challenges remain,such as optimizing the safety and specificity of gene editing tools,improving delivery systems,and overcoming off-target effects,all of which are critical for their successful application in clinical settings.In summary,the continuous evolution of precise gene editing technologies,combined with advancements in delivery systems,is driving the field toward new therapeutic applications that can potentially transform the treatment of genetic disorders by targeting their root causes. 展开更多
关键词 precise gene editing CRISPR/Cas system base editing prime editing gene therapy
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不同功能成分底涂剂对氧化锆耐久粘接强度的影响
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作者 赵莉 赵克 《口腔疾病防治》 2024年第7期502-508,共7页
目的比较含10-甲基丙烯酰氧癸基磷酸酯(10-metracryloyloxdecyl dyhidrogen phosphate,10-MDP)和硅烷的混合型底涂剂与MDP单一功能成分型底涂剂对氧化锆初期及耐久粘接强度的影响。方法制作氧化锆标准试件84个,随机分成4组(n=21),分别... 目的比较含10-甲基丙烯酰氧癸基磷酸酯(10-metracryloyloxdecyl dyhidrogen phosphate,10-MDP)和硅烷的混合型底涂剂与MDP单一功能成分型底涂剂对氧化锆初期及耐久粘接强度的影响。方法制作氧化锆标准试件84个,随机分成4组(n=21),分别使用含10-MDP的Z-Prime Plus(ZP)、含硅烷偶联剂的Monobond-S(MS)、含MDP和硅烷偶联剂的混合型底涂剂Clearfil Ceramic Primer(CCP)、及不使用底涂剂(空白)处理试件表面,再用不含MDP的Duo-Link(DUO)树脂水门汀与氧化锆粘接,形成ZP、MS、CCP及空白对照组共4组粘接试件。每组粘接试件再随机分为3个亚组(n=7),分别进行3个时间点的老化实验,包括37℃恒温水浴24 h、30 d、30 d加3000个5~55℃冷热循环(30 d/TC)。用计算机控制万能材料实验机测定剪切粘接强度值,扫描电镜(scanning electron microscope,SEM)观察并分析断裂试样的粘接界面破坏模式,2-way ANOVA进行统计分析。结果ZP、MS、CCP三组在3个时间点获得的粘接强度值均显著高于空白对照(P<0.01);从24 h到30 d,三组粘接强度值均显著增高(P<0.05);从30 d到30 d/TC,三组粘接强度值均显著下降(P<0.01),并降至基线(24 h)以下水平(30 d/TC vs.24 h,P<0.01)。混合型底涂剂CCP在所有时间点的粘接强度值均高于单一功能成分型底涂剂ZP、MS(P<0.01)。在单一功能成分底涂剂中,ZP在30 d时的粘接强度高于MS(P=0.029),在30 d/TC时却低于MS(P=0.037)。从30 d到30 d/TC,ZP的粘接强度衰减百分率明显高于MS(82.43%vs.64.90%)。结论含MDP和硅烷的混合型底涂剂与氧化锆陶瓷的粘接强度优于单一功能成分型底涂剂。 展开更多
关键词 氧化锆 陶瓷 粘接 底涂剂 Z‐Prime plus Clearfil Ceramic Primer 冷热循环老化
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UPLC-MS/MS测定特殊医学用途配方乳粉中姜黄素类化合物
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作者 公丕学 戴琨 +6 位作者 薛霞 徐大玮 赵寅 王骏 胡梅 张喜琦 刘艳明 《中国乳品工业》 CAS 北大核心 2024年第1期59-64,共6页
建立基于通过式固相萃取净化检测特殊医学用途配方乳粉中姜黄素的超高效液相色谱串联质谱检测方法。样品经80%乙腈提取,通过Oasis PRiME HLB固相萃取柱净化后,以乙腈-0.1%甲酸溶液作为流动相,在acquity UPLC HSS T_(3)色谱柱上进行梯度... 建立基于通过式固相萃取净化检测特殊医学用途配方乳粉中姜黄素的超高效液相色谱串联质谱检测方法。样品经80%乙腈提取,通过Oasis PRiME HLB固相萃取柱净化后,以乙腈-0.1%甲酸溶液作为流动相,在acquity UPLC HSS T_(3)色谱柱上进行梯度洗脱,经超高效液相色谱仪进行分离后,通过电喷雾正离子模式电离,多反应监测模式进行检测分析,外标法定量。对目标物进行稳定性研究,对样品中目标物提取、净化方式、色谱分离条件、质谱条件等关键因素进行了优化。结果表明,3种姜黄素类化合物在25~2 500 ng/mL范围内线性关系好,相关系数高于0.99,加标回收率在87.9%~102.8%之间,精密度在1.31%~4.94%之间,3种姜黄素类化合物的检出限为10μg/kg,定量限为25μg/kg。该方法定性定量结果准确、稳定性好、灵敏度高,能够对特殊医学用途配方乳粉中姜黄素类化合物进行定性分析与定量检测。 展开更多
关键词 姜黄素类化合物 Oasis PRiME HLB 特殊医学用途配方乳粉 液相色谱串联质谱法
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Origin of Sexy Prime Numbers, Origin of Cousin Prime Numbers, Equations from Supposedly Prime Numbers, Origin of the Mersenne Number, Origin of the Fermat Number
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作者 Mady Ndiaye 《Advances in Pure Mathematics》 2024年第5期321-332,共12页
We have found through calculations that the differences between the closest supposed prime numbers other than 2 and 3 defined in the articles are: 2;4: and 6. For those whose difference is equal to 6, we showed their ... We have found through calculations that the differences between the closest supposed prime numbers other than 2 and 3 defined in the articles are: 2;4: and 6. For those whose difference is equal to 6, we showed their origin then we classified them into two categories according to their classes, we showed in which context two prime numbers which differ from 6 are called sexy and in what context they are said real sexy prime. For those whose difference is equal to 4, we showed their origin then we showed that two prime numbers which differ from 4, that is to say two cousin prime numbers, are successive. We made an observation on the supposed prime numbers then we established two pairs of equations from this observation and deduced the origin of the Mersenne number and that of the Fermat number. 展开更多
关键词 Cousin Prime Numbers Sexy Prime Numbers Real Sexy Prime Numbers Equations from Supposed Prime Numbers Mersenne Number Fermat Number Supposed Prime Numbers Prime Numbers
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固相萃取-超高效液相色谱-串联质谱法测定菊花中15种吡咯里西啶生物碱毒素
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作者 章豪 杨挺 +1 位作者 吴银良 朱勇 《食品安全质量检测学报》 CAS 2024年第21期41-49,共9页
目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)测定菊花中15种吡咯里西啶生物碱毒素含量的分析方法。方法样品中吡咯里西啶生物碱毒素采用0.1 mol/L硫酸水溶液提取... 目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)测定菊花中15种吡咯里西啶生物碱毒素含量的分析方法。方法样品中吡咯里西啶生物碱毒素采用0.1 mol/L硫酸水溶液提取,通过Oasis PRiME MCX固相萃取小柱净化,采用UPLC-MS/MS进行分析。采用Acquity UPLC BEH C18色谱柱分离,以0.1%甲酸水-甲醇溶液为流动相进行梯度洗脱,电喷雾离子源正离子电离,多反应离子监测模式监测,外标法定量。结果15种吡咯里西啶生物碱毒素在一定浓度范围内线性关系良好,相关系数(r2)均大于0.999;定量限为0.50~10.00μg/kg,检出限为0.15~3.00μg/kg;阴性样品的加标回收率为82.8%~92.4%,相对标准偏差为2.1%~4.9%(n=5)。结论该方法准确度和精密度高,耗时短,能同时测定多种菊花样品中的多种吡咯里西啶生物碱毒素含量。 展开更多
关键词 吡咯里西啶生物碱毒素 超高效液相色谱-串联质谱法 Oasis PRiME MCX固相萃取小柱 菊花
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Representation of an Integer by a Quadratic Form through the Cornacchia Algorithm
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作者 Moumouni Djassibo Woba 《Applied Mathematics》 2024年第9期614-629,共16页
Cornachia’s algorithm can be adapted to the case of the equation x2+dy2=nand even to the case of ax2+bxy+cy2=n. For the sake of completeness, we have given modalities without proofs (the proof in the case of the equa... Cornachia’s algorithm can be adapted to the case of the equation x2+dy2=nand even to the case of ax2+bxy+cy2=n. For the sake of completeness, we have given modalities without proofs (the proof in the case of the equation x2+y2=n). Starting from a quadratic form with two variables f(x,y)=ax2+bxy+cy2and n an integer. We have shown that a primitive positive solution (u,v)of the equation f(x,y)=nis admissible if it is obtained in the following way: we take α modulo n such that f(α,1)≡0modn, u is the first of the remainders of Euclid’s algorithm associated with n and α that is less than 4cn/| D |) (possibly α itself) and the equation f(x,y)=n. has an integer solution u in y. At the end of our work, it also appears that the Cornacchia algorithm is good for the form n=ax2+bxy+cy2if all the primitive positive integer solutions of the equation f(x,y)=nare admissible, i.e. computable by the algorithmic process. 展开更多
关键词 Quadratic Form Cornacchia Algorithm Associated Polynomials Euclid’s Algorithm Prime Number
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How Prime Numbers Are Interconnected and Built with Two Equations: Addition and Subtraction Rules the Function (6µ)
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作者 John Richard Wisdom 《Advances in Pure Mathematics》 2024年第4期228-241,共14页
Are all prime numbers linked by four simple functions? Can we predict when a prime will appear in a sequence of primes? If we classify primes into two groups, Group 1 for all primes that appear before ζ (such that , ... Are all prime numbers linked by four simple functions? Can we predict when a prime will appear in a sequence of primes? If we classify primes into two groups, Group 1 for all primes that appear before ζ (such that , for instance 5, ), an even number divisible by 3 and 2, and Group 2 for all primes that are after ζ (such that , for instance 7), then we find a simple function: for each prime in each group, , where n is any natural number. If we start a sequence of primes with 5 for Group 1 and 7 for Group 2, we can attribute a μ value for each prime. The μ value can be attributed to every prime greater than 7. Thus for Group 1, and . Using this formula, all the primes appear for , where μ is any natural number. 展开更多
关键词 Number Theory Prime Number Groups Twin Primes Prime Structure and Sequence Prime Subtraction and Addition
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Different Approaches to Reduce Salinity in Salt-Affected Soils and Enhancing Salt Stress Tolerance in Plants
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作者 Amra Bratovcic 《Agricultural Sciences》 2024年第8期830-847,共18页
Salt stress is one of the most harmful environmental stresses in recent times and represents a significant threat to food security. Soil salinization is caused by spontaneous natural processes of mineral dissolution a... Salt stress is one of the most harmful environmental stresses in recent times and represents a significant threat to food security. Soil salinization is caused by spontaneous natural processes of mineral dissolution and human activities such as inappropriate irrigation practices. Natural geological progressions like weathering of rocks, arid climate, and higher evaporation, as well as anthropogenic activities, including the use of brackish water for irrigation, and poor tillage operations, are the foremost causes of soil salinization. Typical characteristics of saline soils are salt stress, high pH, and lack of organic carbon, as well as low availability of nutrients. Disruption of precipitation patterns as well as high average annual temperatures due to climate change additionally negatively affects the process of soil salinization. Productivity and ability to support crop growth are reduced on saline soil. Salinity-induced stress reduces plant growth by modulating the antioxidative system and nutrient orchestration. The aim of this work is to show that the mentioned problems can be alleviated in several ways such as the addition of biochar, exogenous application of several elicitors, seed priming, etc. Research has shown that the addition of biochar can significantly improve the recovery of saline soil. The addition of biochar has no significant effect on soil pH, while the cation exchange capacity of the soil increased by 17%, and the electrical conductivity of the saturated paste extract decreased by 13.2% (depends on the initial salinity and the type of biochar raw material). Moreover, biochar enriched with silicon increases the resistance of bananas to salt stress. In addition, exogenous application of several elicitors helps plants to alleviate stress by inducing stress-related physicochemical and molecular changes (selenium, sulfur, silicon, salicylic acid). Finally, seed priming showed positive effects on metabolomics, proteomics and growth of plants subjected to abiotic stress. Priming usually involves immersing the seed in a solution for a period of time to induce physiological and metabolic progression prior to germination. 展开更多
关键词 Salt-Affected Soils Salt Stress BIOCHAR ELICITORS Seed priming
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Preliminary Identification of a Prime Number Other Than 2 and 3, the Origin of Twin Prime Numbers, the Structure of the Chain of Prime Numbers and the Set of Prime Numbers Less Than a Given Integer
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作者 Mady Ndiaye 《Advances in Pure Mathematics》 2024年第1期30-48,共19页
The application of the Euclidean division theorem for the positive integers allowed us to establish a set which contains all the prime numbers and this set we called it set of supposedly prime numbers and we noted it ... The application of the Euclidean division theorem for the positive integers allowed us to establish a set which contains all the prime numbers and this set we called it set of supposedly prime numbers and we noted it E<sub>sp</sub>. We subsequently established from the previous set the set of non-prime numbers (the set of numbers belonging to this set and which are not prime) denoted E<sub>np</sub>. We then extracted from the set of supposedly prime numbers the numbers which are not prime and the set of remaining number constitutes the set of prime numbers denoted E<sub>p</sub>. We have deduced from the previous set, the set of prime numbers between two natural numbers. We have explained during our demonstrations the origin of the twin prime numbers and the structure of the chain of prime numbers. 展开更多
关键词 Supposedly Prime Numbers Non-Prime Numbers Prime Numbers Prime Numbers Less Than a Given Integer Prime Numbers between Two Given Integers
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PRiME HLB固相萃取结合UPLC-QTOF-MS测定烟液与烟丝中的依托咪酯
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作者 王华 罗达龙 +5 位作者 覃蓝 莫惠欣 李媛捷 何姗珊 杨梓莹 刘虹虹 《分析仪器》 CAS 2024年第5期25-30,共6页
待测样品经乙腈提取后,使用PRi ME HLB固相萃取柱对样品提取液进行净化,经ACE EXCEL C18(2.1mm×50mm,2μm)色谱柱分离,以甲醇-5mmol·L^(-1)甲酸铵水溶液(含0.1%甲酸)作为流动相,梯度洗脱,采用电喷雾离子源正模式(ESI+),目标... 待测样品经乙腈提取后,使用PRi ME HLB固相萃取柱对样品提取液进行净化,经ACE EXCEL C18(2.1mm×50mm,2μm)色谱柱分离,以甲醇-5mmol·L^(-1)甲酸铵水溶液(含0.1%甲酸)作为流动相,梯度洗脱,采用电喷雾离子源正模式(ESI+),目标物二级离子模式(Targeted MS/MS)进行质谱分析。依托咪酯在2ng·m L^(-1)~200ng·m L^(-1)浓度范围内线性关系良好,相关系数r为0.999,在0.2μg·g^(-1),1.0μg·g^(-1),5.0μg·g^(-1)3个水平的加标回收率为86.6%~94.6%,RSD为3.1%~4.3%(n=9)。本方法具有操作简易快速、定性定量准确等特点。 展开更多
关键词 依托咪酯 四极杆飞行时间质谱 电子烟 PRiME HLB固相萃取
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The Periodic Table of Primes
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作者 Han-Lin Li Shu-Cherng Fang Way Kuo 《Advances in Pure Mathematics》 2024年第5期394-419,共26页
Over millennia, nobody has been able to predict where prime numbers sprout or how they spread. This study establishes the Periodic Table of Primes (PTP) using four prime numbers 2, 3, 5, and 7. We identify 48 integers... Over millennia, nobody has been able to predict where prime numbers sprout or how they spread. This study establishes the Periodic Table of Primes (PTP) using four prime numbers 2, 3, 5, and 7. We identify 48 integers out of a period 2×3×5×7=210 to be the roots of all primes as well as composites without factors of 2, 3, 5, and 7. Each prime, twin primes, or composite without factors of 2, 3, 5, and 7 is an offspring of the 48 integers uniquely allocated on the PTP. Three major establishments made in the article are the Formula of Primes, the Periodic Table of Primes, and the Counting Functions of Primes and Twin Primes. 展开更多
关键词 PRIMES COMPOSITES the Periodic Table of Primes
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