Prime Editing: An All-Rounder for Genome Editing

Prime editing (PE), as a “search-and-replace” genome editing technology, has shown the attractive potential of versatile genome editing ability, which is, in principle, currently superior to other well-established genome-editing technologies in the all-in-one operation scope. However, essential technological solutions of PE technology, such as the improvement of genome editing efficiency, the inhibition of potential off-targets and intended edits accounting for unexpected side-effects, and the development of effective delivery systems, are necessary to broaden its application. Since the advent of PE, many optimizations have been performed on PE systems to improve their performance, resulting in bright prospects for application in many fields. This review briefly discusses the development of PE technology, including its functional principle, noteworthy barriers restraining its application, current efforts in technical optimization, and its application directions and potential risks. This review may provide a concise and informative insight into the burgeoning field of PE, highlight the exciting prospects for this powerful tool, and provide clues for questions that may propel the field forward.     

Chromosome-Level Genome Assembly of a Fragrant Japonica Rice Cultivar ‘Changxianggeng 1813’ Provides Insights into Genomic Variations between Fragrant and Non-Fragrant Japonica Rice

East Asia has an abundant resource of fragrant japonica rice that is gaining increasing interest among both consumers and producers. However, genomic resources and in particular complete genome sequences currently available for the breeding of fragrant japonica rice are still scarce. Here, integrating Nanopore long-read sequencing, Illumina short-read sequencing, and Hi-C methods, we presented a high-quality chromosome-level genome assembly (~378.78 Mb) for a new fragrant japonica cultivar ‘Changxianggeng 1813’, with 31,671 predicated protein-coding genes. Based on the annotated genome sequence, we demonstrated that it was the badh2-E2 type of deletion (a 7-bp deletion in the second exon) that caused fragrance in ‘Changxianggeng 1813’. Comparative genomic analyses revealed that multiple gene families involved in the abiotic stress response were expanded in the ‘Changxianggeng 1813’ genome, which further supported the previous finding that no generalized loss of abiotic stress tolerance associated with the fragrance phenotype. Although the ‘Changxianggeng 1813’ genome showed high genomic synteny with the genome of the non-fragrant japonica rice cultivar Nipponbare, a total of 289,970 single nucleotide polymorphisms (SNPs), 96,093 small insertion-deletion polymorphisms (InDels), and 8690 large structure variants (SVs, >1000 bp) were identified between them. Together, these genomic resources will be valuable for elucidating the mechanisms underlying economically important traits and have wide-ranging implications for genomics-assisted breeding in fragrant japonica rice.     

磨机负荷检测系统无线数据采集装置的研制

针对球磨机振动信号采集及数据传输,研制了一套低功耗无线采集传输系统。通过对电路系统的降噪设计,提高了处理精度,使其完全满足数据采集的需要,解决了在线检测球磨机桶壁振动装置的连续使用问题。     

染料废水处理技术现状与发展

采用十二烷基三甲基氯化铵对高炉矿渣进行改性,制备一种低成本、环境友好型的吸附剂来处理染料废水,研究分析了吸附剂剂量、吸附时间、染料初始浓度和pH值因素对改性矿渣吸附活性艳蓝KN-R能力的影响以及改性矿渣表征的变化规律。结果表明：当改性矿渣用量为10 g/L,染料初始浓度为60 mg/L,pH值为2,以及吸附120 min时,改性矿渣对污水的处理后可达到较大脱色率96%,而在初始浓度为150 mg/L时为较优溶度,该浓度下脱色率与吸附量均较高。通过XRD和FTIR实验对矿渣与改性矿渣的表征特点进行对比分析,分析表明十二烷基三甲基氯化铵可以有效地对矿渣进行改性,改性后的矿渣吸附能力得到了显著提升。     

茉莉酸甲酯和乙烯利处理对鲜切苹果膜质过氧化反应的影响

为研究外源信号分子茉莉酸甲酯(Me JA)和乙烯(Eth)对鲜切果蔬膜脂过氧化反应的影响,本实验以鲜切富士苹果为实验材料,经10μmol/L Me JA和10μL/L乙烯利处理,分析贮藏过程中与膜脂过氧化反应相关物质及酶类的变化。结果表明,Me JA和乙烯利可显著提高脂氧合酶(LOX)活性(p<0.05),降低细胞膜的渗透率和丙二醛(MDA)的含量,同时颜色的损失减少,乙烯利处理鲜切苹果的过氧化氢酶(CAT)活性提高,超氧化物歧化酶(SOD)活性降低,但Me JA对SOD和CAT活性无显著影响,说明Me JA和乙烯利启动了鲜切富士苹果的防御反应,导致膜脂过氧化反应系统的关键酶活性升高,从而降低机械胁迫对细胞膜产生的伤害,从而显著延长贮藏期和保持新鲜品质(p<0.05)。      

食品中展青霉素检测方法及脱除技术研究进展

展青霉素是由多种真菌产生的一种有毒代谢产物,广泛存在于自然界中,易在水果及其制品中残留,并可通过食物链进行富集,严重威胁人类健康。本文对展青霉素的来源、性质、检测、脱除、存在问题及研究趋势进行概述,为后续研究提供理论依据。      

食源性MRSA氨基糖苷类耐药基因多重PCR方法建立

目的:了解食源性金黄色葡萄球菌中耐甲氧西林金黄色葡萄球菌（methicillin-resistant Staphylococcus aureus,MRSA）及对氨基糖苷类庆大霉素、卡那霉素抗生素的耐药性情况,并建立快速检测鉴定金黄色葡萄球菌耐药性多重PCR方法。方法:对金黄色葡萄球菌进行增菌培养,并提取DNA作为模板,以nuc基因作为菌属鉴定基因,mec A基因作为MRSA检测基因,aac A-aph D及aph（3’）-Ⅲa基因作为耐氨基糖苷类庆大霉素、卡那霉素的检测目的基因,建立四重PCR检测方法并进行特异性及灵敏度评价;利用所建立的方法检测72株食品及食物中毒患者来源的金黄色葡萄球菌。结果:成功建立四重PCR检测方法,且72株金黄色葡萄球菌均有nuc基因检出,mec A基因与MRSA检测符合率达100%,aac A-aph D、aph（3’）-Ⅲa基因与庆大霉素、卡那霉素耐药菌株的符合率达95.12%。结论:本实验所建立的多重PCR方法灵敏度高、特异性好,可以快速检测出MRSA,并对氨基糖苷类庆大霉素、卡那霉素耐药菌株检测具有较高的准确率。      

混合菌种发酵酸马乳的降血脂功能研究

为研究混合菌种发酵酸马乳的降血脂作用,采用混合菌种发酵酸马乳对小鼠进行实验,研究其对高脂模型小鼠体重、血脂水平、脏器指数和动脉硬化（AI）指数的影响。结果表明,混合菌种发酵酸马乳中、高剂量能够显著降低高血脂症小鼠TC、TG、LDL-C、AI水平（p<0.05）,显著升高HLD-C水平（p<0.05）,并且能降低小鼠体重和肝脏指数,说明混合菌种发酵酸马乳对实验性高脂血症小鼠具有降低血脂的作用,对高脂血症及动脉粥样硬化具有一定的预防作用。      

激光冲击强化设备控制系统

针对复杂曲面类零件,研发一种新型表面激光冲击强化的控制系统,该系统是一套全自动可控操作系统,通过工控机/PLC集成控制,实现自动化、数字化控制,并完成实时在线监控和信息交互反馈,属于开放式分布系统。该系统用于激光冲击强化核心设备(包括激光器、机器人、辅助控制、质量检测装置与辅助系统等),实现各环节的信息交互和系统的协同工作,通过实时监控系统,远程观察加工状态,有效避免重大事故的发生。同时,该控制系统添加激光冲击强化工艺试验数据记录功能,可根据实际需求调用后台工艺参数数据库,实现高效工艺参数优化。除此之外,该系统还能够实现激光冲击强化模型建立、加工过程有限元模拟、复杂曲面加工轨迹自动规划、加工策略制定等功能,从而实现激光冲击强化自动化生产,目前已经处于工程应用阶段。     

激光冲击强化技术的应用现状与发展

激光冲击强化是一种利用激光诱导等离子体冲击波来提高材料疲劳寿命的新型表面改性技术,具有强化效果显著、可控性强、适应性好等优点,对提高结构可靠性和部件疲劳强度、延长材料使用寿命具有重要作用。近年来,该技术受到了广泛重视,得到了快速发展。本文简要介绍了激光冲击强化技术的基本原理、特点与应用领域;总结了国内外激光冲击强化技术的发展状况与研究成果;并针对国内外激光冲击强化技术的现状,提出了一些现在需要解决的强化工艺问题;最后对激光冲击强化技术的应用前景进行了展望。