Evaluating the external value of rice production environment in the Yangtze River Economic Belt can make up for the lack of attention to the pre-production link of rice in literature, and thus provide a basis for promoting agricultural green production. Based on the panel data of rice production in the Yangtze River Economic Belt from 2000 to 2024, we used the functional value method and the equivalent factor method to calculate the 20 environmental externalities across 11 provinces and cities in the Yangtze River Economic Belt, and analyzed the spatial and temporal variations. The results showed that the annual environmental positive, negative externality and net value of rice production from 2000 to 2024 in the Yangtze River Economic Belt were 344.476 billion, 284.605 billion, and 59.871 billion yuan, respectively. The positive externality value was mainly composed of water conservation (50.1%) and gas regulation (21.7%). The negative externality value was mainly composed of water consumption (27.8%), fertilizer pollution (27.2%), and greenhouse gas emissions (22.2%). During the study period, the overall value of positive externality showed a downward trend, and the value of negative externality showed a trend of increasing first and then decreasing with 2012 as the demarcation point. The average annual net external value of rice production environment in the lower, middle, and upper reaches of the Yangtze River Economic Belt was 7.892 billion, 46.679 billion, and 6.099 billion yuan, respectively. The net external value of rice production in Jiangxi and Hunan was the highest, which together contributed more than 2/3 of the whole study area. The net external value of Yunnan was the lowest. Our results could provide scientific basis for the optimal layout and green transformation of rice production in the Yangtze River Economic Belt.

The emerging contaminant chlorinated polyfluoroalkyl ether sulfonic acid (Cl-PFESA, trade name F-53B) damages mitotic cell viability leading to inhibited vegetative development in plants. However, its impact on plant reproductive development remains elusive. In this study, by using a combination of cytogenetic and microscopic approaches, we analyzed gametogenesis and meiosis in Arabidopsis (Arabidopsis thaliana) exposed to F-53B (50 or 100 μM). We show that F-53B disrupts embryo development and gametogenesis leading to reduced fertility. Moreover, F-53B interferes with chromosome distribution and microtubule organization during male meiosis. Remarkably, we show that F-53B lowers crossover rate possibly by reducing double-strand break formation. This study unveils the toxicity of F-53B to gametophytic cell viability and meiosis in plants, which highlights the concerns on its potential threats to agricultural safety and biological diversity considering its global distribution at a wide range of environmental matrices.

The emerging contaminant Cl-PFESA/F-53B damages vegetative development in plants and has been evidenced to be toxic to both mitotic and meiotic cells in animals. We have recently reported that F-53B induces nuclei unviability in meristematic cells leading to disrupted root development in Arabidopsis ( Arabidopsis thaliana ). However, the toxicity of F-53B to reproductive system in plants remains unelucidated. In this study, by using cytogenetic and microscopic approaches, we analyzed embryo and anther development and multiple meiosis processes in Arabidopsis exposed to 50 or 100 μM F-53B. We showed that F-53B disrupts embryo development which results in reduced seed setting in Arabidopsis. Histochemical staining of anthers and a live-imaging assay using a reporter line that expresses GFP-tagged Aborted Microspores (AMS), a key regulator of the tapetum, demonstrated that F-53B impairs anther development. Moreover, we showed that F-53B interferes with chromosome segregation and/or distribution and alters microtubule organization during male meiosis. Quantification of the chiasmata and immunolocalization of the Human Enhancer of Invasion 10 (HEI10) protein on diakinesis chromosomes suggested that F-53B reduces crossover rate. Furthermore, F-53B reduced the number of DNA Meiotic Recombinase 1 (DMC1) protein foci on zygotene chromosomes in Arabidopsis wild-type Columbia-0 (Col-0), and it partially promoted meiotic chromosome integrity in Arabidopsis depleted with Ataxia Telangiectasia Mutated ( ATM ), a central regulator of DNA double-strand break (DSB) repair, which suggested that F-53B reduces meiotic DSB formation. Taken together, our study reveals the toxicity of F-53B to meiotic cells and reproduction in Arabidopsis, which highlights its potential threats to agricultural safety and ecological diversity. Highlight ### Competing Interest Statement The authors have declared no competing interest.

The emerging contaminant chlorinated polyfluoroalkyl ether sulfonate (Cl-PFAES/F-53B) has been detected in many plant species, however, the impact of F-53B on the development in plants and the underpinning mechanisms remain largely unelucidated. In this study, we demonstrate by molecular biology, cytogenetics, and fluorescence microscopy mythologies that F-53B impairs cell viability leading to disrupted root development in Arabidopsis ( Arabidopsis thaliana ). We show that F-53B suppresses root length and the inhibitory effect is pronunanced at increasing concentrations. F-53B disrupts cell wall and microtubule-mediated cell plate formation and configuration in meristem cells, revealing its toxicity to cell division and cytoskeleton organization. F-53B induces cell death predominantly at the meristematic zone, however, gene exression and genetic studies indicate that F-53B does not trigger DNA double-strand breaks, implying a divergent effect on DNA stability across species. Moreover, we show that F-53B damages nuclei stability and viability, and induces Autophagy-Related 8 protein foci formation implying that it triggers autophagy-mediated cell responses. Taken together, this study provides cellular and molecular insights into the toxicity of F-53B to plant cells, which highlights its damage to agriculture and ecology security that deserve imperative environmental management actions. Environmental Implication F-53B has been detected in many plant species, which raises increasing concerns on its toxicity to plants and thus agriculture and ecology safety. However, the toxicity of F-53B to development in plants and the underpinning mechanisms remain largely unelucidated. Here, we demonstrate that F-53B damages nuclei stability and viability leading to cell death and impaired root development in the model plant species Arabidopsis thaliana . Our study provides cytogenetic and molecular insights into the F-53B toxicity to plant cells, which highlights imperative environmental management actions and can be referenced for developing F-53B control and management policies. ![Figure][1] One-sentence summary F-53B triggers DNA double-strand break-free cell unviability leading to impaired meristematic cell division and root development in plants. HIGHLIGHTS ### Competing Interest Statement The authors have declared no competing interest. [1]: pending:yes

Soil cadmium（Cd） in paddy fields is easy to accumulate in rice and thus harms human health through the food chain. The effect of groundwater level and long-term straw return on the Cd availability in paddy soils and Cd uptake and accumulation characteristics in rice tissues is worthy of attention. In this study, a long-term experiment on red loamy paddy soils was conducted.Four treatments of high groundwater level（-20 cm） with straw return（HRS）, high groundwater level with chemical fertilizer（HCF）,low groundwater level（-80 cm） with straw return（LRS） and low groundwater level with chemical fertilizer（LCF） were selected to determine the concentration of soil Cd（Cd） availability, each form of Cd（BCR method） and aboveground Cd in rice plant. The effects of groundwater level and straw return on the availability and transformation of Cd in soil and Cd concentration in rice grain were analyzed. The results showed that under long-term straw return and the same groundwater level, the availability of soil Cd was increased. The soil Cd availability in the HRS and LRS treatments was 49.4% and 53.2% higher than that in the HCF and LCF treatments, respectively. The soil Cd availability at low groundwater level was higher than that at high groundwater level under the same fertilizer treatment. Compared with HCF and HRS, the soil available Cd concentrations of LCF and LRS treatment were 46.5%and 50.2% higher, respectively. High groundwater level under RS promoted the transformation of residual Cd to oxidizable and reducible Cd. High groundwater level under chemical fertilizer treatment promoted the transformation of acid-extracted Cd to reducible and oxidizable Cd. The rice grain Cd concentration in the straw return treatment was significantly higher than that in the chemical fertilizer treatment at the same groundwater level. The Cd concentration in rice grain of RS treatment was 11.6 times higher than that of chemical fertilizer treatment at high water level, and 42.3% higher at low groundwater level. Under the same fertilizer treatments,the Cd concentration in rice grain at high groundwater level was significantly lower than that at low groundwater level. The Cd concentration in rice grain at high groundwater level was 57.4% lower than that at low groundwater level under RS, and 95.2% lower under chemical fertilizer treatment. The results of stepwise regression analysis showed that the concentration of soil available Cd was significantly affected by the concentration of dissolved organic carbon. The concentration of Cd in rice grain and straw was significantly affected by the concentration of soil available Cd and available Fe. The groundwater level and long-term straw returning can change the availability and proportion of Cd forms in soil, thus affecting the absorption of Cd by rice. Straw returning to the field under high and low groundwater levels increased the availability of Cd in soil and the concentration of Cd in rice grain, which brought the risk of exceeding the standard of Cd of rice grain.

为保护种质资源、确保莼菜高产稳产,随机选取利川市凉雾乡马前继昌村莼菜种植基地的水田,选用有机肥、有机无机复混肥和配方肥3种肥料,设4个水平,3次重复,1次对照,进行完全随机区组设计,彩钢板分割区块进行大田施肥试验.采用当地常规的田间管理和收获技术,以分析对莼菜生长发育和产量的影响.结果显示,不同浓度的3种肥料对当地莼菜生长发育和产量未产生显著影响,产量指标比较稳定一致.

随机检测了5处主产区水土的农化因子,并分析了与莼菜生长发育和产量的相关关系.结果显示,虽然各田块间部分因子存在极显著或显著差异,但基本低于相关标准或处于前人研究的正常值范围内.说明莼菜田水土未受到人类农事活动的污染,化学性质总体上较稳定,田块间莼菜生长发育和产量未出现显著差异,且与农化因子之间也无显著相关性.说明当前莼菜田水土和周边生态环境条件良好,莼菜的生长和产量可能主要与栽培管理措施有关,该研究结果为探索莼菜高产栽培技术和制定保护策略奠定了基础.

针对课程思政如何在专业课程上开展和推进,以细胞生物学专业课作为研究对象,制订整体目标和实施思路,实现课程思政贯穿专业课程教育教学的全过程,方案和举措实用性强,适用于理工农医等各专业课程的推广.

在立德树人的价值引领教育中,生命科学的知识体系是对学生进行生命价值观塑造的良好素材.理论体系中涉及的下列理念是应该贯彻的.人作为自然演化的最高等形式,在生命科学理论体系中应贯彻生命至上的理念;同时生物是自然演化的产物,应尊重生命的唯物主义的历史观,同时又需尊重人与自然的和谐共生、尊重现存生物个体的多样性,从而做到敬畏生命,敬畏自然.就生命本身而言,生命个体是复杂性和矛盾性的统一;科学思维的阶段性和螺旋式上升体现人类认识生命规律的创新性和批判性.生命科学理论体系所涉及的思政元素,为生命科学领域课程思政的实施提供了着力点和目标方向.新时代教师积极性、主动性、创造性的发挥和能力提升,是实现学生价值观引领的关键所在.

为研究莼菜内生细菌的多样性,挖掘莼菜的内生细菌资源,采用Illumina MiSeq高通量二代测序技术对莼菜不同组织及水样进行了Alpha、Beta多样性分析,分析细菌群落的结构组成以及对比KEGG数据库进行内生细菌菌群基因功能预测.莼菜样品和水样中获得16S rRNA基因V3-V4区高质量序列1124709条,1391个细菌OTUs隶属于21个门和399个属.分析结果表明:莼菜内生细菌的优势菌群为变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、放线菌门(Actinobacteria)、拟杆菌门(Bacteroidetes),水样和莼菜组织间共有29个共有菌属,占内生细菌所有种类的7.27％.PICRUSt2功能预测发现内生细菌菌群共有34个子功能,菌群功能丰富,代谢为最主要的功能.莼菜茎的内生细菌多样性大于其他组织,且不同组织均有各自特异的菌属,推测植物组织结构可能会促进内生细菌选择合适的组织生态位为植物体提供动力.

本文基于IPCC排放因子法借助化石能源的碳排放量与水泥生产的碳排放量两部分数据,核算2013—2017年长沙市的碳足迹并分析其动态变化,通过林地、农作物的固碳能力核算长沙市的碳承载力.结果显示,2013—2017年长沙市碳足迹呈下降趋势,碳承载力呈上升趋势,但变化趋势都在逐步放缓.未来较长时期长沙市净碳足迹还会持续下降,但仍处于碳赤字状态.能源消费结构决定了长沙市仅依靠能源利用效率的提高很难达到快速降低碳排放的效果.调整能源结构,低碳新能源的使用,可以快速降低碳排放量.

Alterations of environmental temperature affect multiple meiosis processes in flowering plants. Polyploid plants derived from whole genome duplication (WGD) have enhanced genetic plasticity and tolerance to environmental stress, but meanwhile face a challenge for organization and segregation of doubled chromosome sets. In this study, we investigated the impact of increased environmental temperature on male meiosis in autotetraploid Arabidopsis thaliana . Under low to mildly-increased temperatures (5-28°C), irregular chromosome segregation universally takes place in synthesized autotetraploid Columbia-0 (Col-0). Similar meiosis lesions occur in autotetraploid rice ( Oryza sativa L.) and allotetraploid canola ( Brassica napus cv. Westar), but not in evolutionary-derived hexaploid wheat ( Triticum aestivum ). As temperature increases to extremely high, chromosome separation and tetrad formation are severely disordered due to univalent formation caused by suppressed crossing-over. We found a strong correlation between tetravalent formation and successful chromosome pairing, both of which are negatively correlated with temperature elevation, suggesting that increased temperature interferes with crossing-over prominently by impacting homolog pairing. Besides, we showed that loading irregularities of axis proteins ASY1 and ASY4 co-localize on the chromosomes of syn1 mutant, and the heat-stressed diploid and autotetraploid Col-0, revealing that heat stress affects lateral region of synaptonemal complex (SC) by impacting stability of axis. Moreover, we showed that chromosome axis and SC in autotetraploid Col-0 are more sensitive to increased temperature than that of diploid Arabidopsis. Taken together, our study provide evidence suggesting that WGD without evolutionary and/or natural adaption negatively affects stability and thermal tolerance of meiotic recombination in Arabidopsis thaliana .

为探究一种简单、经济和可靠的微塑料分离提取手段,设立了11种(F1～F11)具有不同体积比的饱和NaCl和饱和NaI溶液的混合溶液,将混合液作为浮选液来提取土壤中的4种类型(聚乙烯,PE;聚苯乙烯,PS;聚氯乙烯,PVC;聚对苯二甲酸乙二醇酯,PET)微塑料,同时对浮选过程进行了改进.结果表明:当单独使用NaCl溶液浮选时,微塑料的总提取率为55.83％,但随着NaI所占体积比的不断增加,微塑料的总提取率基本呈上升趋势,在NaCl:NaI=1:1时总提取率超过了90％,在只有NaI的条件下总提取率高达96.67％;在F1～F11的任意条件下,PE和PS表现为较高的提取率,均超过了86.67％;PVC和PET在单独使用NaCl溶液浮选时提取率极低,在NaCl:NaI=1:1条件下提取率分别为93.33％和90％,接近单独使用NaI溶液浮选时的提取率;F1～F11任意条件下,低密度微塑料PE和PS的提取率之和均高于高密度微塑料PVC和PET的提取率之和,但在F6～F11条件下提取率差值不大.根据提取结果并结合经济成本等多方面因素考虑,建议使用NaCl:NaI=1:1的混合溶液来分离土壤中的微塑料.

高校的立身之本在于立德树人,思政课是落实立德树人根本任务的关键,而课程思政则是对思政课程的进一步补充,在高校人才培养中起到非常重要的作用.作为理工科学院,如何在课程中融入思政元素,发挥课程的育人作用,提高培养学生的质量,是值得每一位教师毕生研究的课题.该文以"细胞生物学"课堂为例,探究在生物学科的教学工作中如何更好地融合课程思政.

GABA在植物发育中的研究已有70多年,但GABA参与信号途径涉及的许多关键科学问题仍悬而未决.其中,GABA受体、GABA是否可以远距离运输的问题阐明仍然是制约GABA在农作物调控运用中的关键科学问题.最近的研究揭示了类谷氨酸受体GLR(glutamate receptor-like)胞外LAOBP-Like和LIVBP-Like结构域可能具有GABA信号分子结合的潜在靶点.此外,新型GABA检测荧光探针(iGABASnFR)的开发为回答这些科学问题提供了基本的方法和技术手段.为回答GABA调控农作物发育信号途径的两个关键科学问题,对GLR胞外结构域进行了进一步研究,筛选出特异性响应GABA的候选受体蛋白,同时构建了适合植物体系的GABA和Ca2+的荧光探针,动态追踪GABA的动态变化,为最终阐释GABA调控植物的信号途径奠定了理论和方法基础.

为充分利用细胞生物学教学课堂思政来培养学生的批判性思维,以细胞生物学教学中的课程思政和批判性思维为课题,从分析细胞生物学教学中的课程思政与培养学生批判性思维之间的互为因果关系入手,对其进行了全方位、深层次探析,并在此基础上分析了利用细胞生物学教学中课堂思政培养学生批判性思维的策略.

γ-氨基丁酸(GABA)是植物发育的代谢性信号分子.GABA合成突变体的第一对真叶面积不同程度大于野生型,且突变体的叶表皮细胞的面积大于野生型.流式细胞分析表明GABA合成突变体叶片中多倍体细胞出现早于且比例高于野生型.为研究GABA合成突变体叶片细胞增大和内复制的相关性,对内复制调控因子D类细胞周期蛋白基因(CYCD3;1、CYCD3;2、CYCD3;3和CYCD4;1)和细胞周期蛋白依赖的激酶CDKA;1进行了荧光定量PCR分析.结果 表明,GABA合成突变体中CDKA;1的表达量呈现下调趋势.CCS52A (cell cycle switch 52A)在细胞周期退出和内复制进入过程中发挥了重要作用.gad2和gadl/gad2突变体中,CCS52A2的相对表达量明显高于野生型.参与激酶活性抑制的SIM (siamese)、SMR (siamese-related)的表达水平显著高于野生型.为进一步研究GABA合成代谢异常与内复制调控的潜在关系,用活性氧(ROS)的荧光探针分析了叶片保卫细胞中的ROS水平.结果 表明,GABA合成突变体中ROS的水平明显高于对照.本研究证明了GABA合成突变体叶片面积增大过程中,周期蛋白、周期蛋白依赖的激酶以及激酶的抑制蛋白在转录水平协调参与了叶片内复制相关的叶片面积调控.本研究首次揭示了GABA正常代谢是阻止叶片细胞早熟分化、保证叶片正常发育相关的内复制发生的负反馈调节因子.

以锰矿区旱土和底泥为研究对象,探索了研究区内Mn、Pb、Cu、Zn、As的空间分布特征和相关关系.结果 表明,样点中Mn、Pb、Cu、Zn、As含量均超过湖南省土壤背景值.单因子指数表明旱土中Mn为中度污染,As、Zn、Cu为轻度污染,Pb为清洁水平;底泥中Mn、As、Cu为轻度污染,Pb、Zn为清洁水平.锰矿区Mn、Pb、Zn空间分布情况较相似,呈以锰尾渣堆为中心逐步向四围递减的放射状,Cu、As空间分布呈以某块区域为中心向西北方向逐步递减.

This paper analyzes and experiments on the main problems in the safety and environmental protection of the drug research laboratory of the South-Central University for Nationalities (SCUN), and proposes improvement suggestions from the following three aspects: recovering toxic and harmful volatile organic solvents (including various mixed solvents), and reusing; optimizing the experimental content and methods, reducing or replacing the use of toxic and harmful reagents, reducing the emission of toxic substances, reducing environmental pollution, improving the safety of laboratory; learning from HACCP (hazards analysis and critical control points)method and establishing laboratory management rules for safety and environmental risks. It has been proved by practice that they can effectively solve the safety and environmental protection problems of pharmaceutical laboratories.