核酸适配体在感染性疾病诊治中的研究进展

临床上，感染性疾病由于诊断不明或诊断时间较长导致严重后果的情况并不罕见。近年来，由于新型病原体感染报道层出不穷，现有病原体出现耐药也十分普遍，导致感染性疾病的诊断和治疗仍是临床上亟待解决的难题。核酸适配体是通过体外反复筛选或指数富集配体系统进化(systematic evolution of ligands by exponential enrichment，SELEX)技术筛选出来的一类具有特异性识别能力的寡核苷酸序列，具有靶向结合目标分子的能力，可用于病原体检测和新型治疗性药物的开发。适配体已在感染性疾病诊治中显现良好的应用前景，进一步推进相关研究有望为感染性疾病的诊治提供新的途径。     

氮负荷增强对闽江河口芦苇残体分解及其养分释放的影响

选择闽江河口鳝鱼滩西北部的纯芦苇湿地为研究对象，基于野外氮负荷增强分解试验，探讨了氮负荷增强对芦苇残体分解及其养分释放的影响。试验设置了4个氮负荷水平，即NL0（无氮负荷处理，0 g N m^-2 a^-1）、NL1（低氮负荷处理，12.5 g N m^-2 a^-1）、NL2（中氮负荷处理，25.0 g N m^-2 a^-1）和NL3（高氮负荷处理，75.0 g N m^-2 a^-1）。结果表明，不同氮负荷处理下残体的分解速率整体表现为NL2（0.00284 d^-1）>NL1（0.00263 d^-1）>NL0（0.00257 d^-1）>NL3（0.00250 d^-1），低氮和中氮负荷总体促进了残体分解，而高氮负荷抑制了残体分解，原因主要与不同处理下残体分解过程中基质质量及pH的明显改变有关。不同氮负荷处理下，残体中的全碳（TC）含量在分解期间均呈不同波动变化特征；全氮（TN）和全磷（TP）含量均在分解初期（0-30 d）骤然降低，之后则呈不同波动变化，其中TN含量呈波动上升变化，而TP含量呈小幅波动变化。残留率是影响不同氮负荷处理下残体分解期间碳（C）、氮（N）和磷（P）净释放的共性因素，而氮负荷增强导致的残体基质质量（C/N、C/P、N/P）和主要环境因子（pH、电导率（EC））改变影响了其释放强度。研究发现，在氮负荷增强背景下残体养分的累积与释放发生了明显改变，闽江河口氮负荷水平的增加整体将抑制芦苇残体中C、N养分的释放，但其在分解中后期（90-240 d）可能对P养分释放具有较为明显的促进作用。     

福建省土地利用碳排放空间关联性与碳平衡分区

全球变暖与二氧化碳浓度升高密不可分，在工业化及城镇化发展过程中，人类对土地的利用和改造是造成全球大气中含碳量迅速增加的重要原因，且土地在利用过程中碳减排的潜力较大。因此，从不同土地利用方式视角研究福建省碳排放量，采用基尼系数来衡量福建省各设区市碳收支的空间差异，探索区域内土地利用碳收支规模和空间分异；运用社会网络分析方法对福建省土地利用碳排放空间网络结构的整体特征和设区市在网络结构中的角色进行考察，有助于从基础层面对人类活动所造成的环境影响进行评估，及时调整土地利用方式从而促进低碳经济发展。结果表明：2006-2018年福建省土地利用净碳排放量逐年递增，呈现东高西低的空间分布特征，建设用地是主要碳源，而林地起到主要碳汇的作用；区域内碳补偿率逐年递减且存在明显的空间差异，经济较发达的区域碳补偿率低于经济欠发达的区域，生态承载系数东西差距不断加强，东部地区碳排放的比例明显超过了碳吸收的比例；福建省土地利用碳排放在空间上具有明显的关联性和溢出效应，碳排放空间关联网络越来越复杂、稳定，各设区市在网络中所处地位和作用存在明显的不均衡性，厦门市在整个碳排放网络中占据领导地位，其他城市的碳影响力在网络中的地位及作用随着经济联系逐渐加强正在逐步提高；对网络空间聚类发现，第一模块和第三模块对模块内外均有溢出效应且密度值较大，属于"双向溢出模块"，其余第二、四模块均属于"净收益模块"。在研究的基础上将福建省各设区市分为3类区域：低碳优化区、碳总量控制区和碳汇功能区，并提出协同减排的差异性对策建议。     

Geographic patterns of Lucanus (Coleoptera: Lucanidae) species diversity and environmental determinants in China

Clarifying the geographic patterns of species diversity and the determinant factors can provide essential information for species conservation and management. Stag beetles (Coleoptera: Lucanidae) of Lucanus are important saproxylic insects and can be used for biomonitoring forests. Most of Lucanus species are facing conservation concerns due to their limited distribution and fragmented habitats, particularly in China, which has the richest species diversity of this genus. The distribution patterns of species diversity of Lucanus at large spatial scales remain portly understood. We studied the distribution patterns of Lucanus and its environmental and geographic determinants in China. Distribution data for 72 species and subspecies were examined. All these species are distributed in southern China except for Lucanus maculifemoratus dybowskyi, which is mainly distributed in north China. The hotspot for Lucanus in China is southeastern Tibet. Our study indicated that the species richness of Lucanus in China was shaped by the precipitation of the wettest and driest month, net primary productivity, digital elevation model, and latitude at a large scale. These variables collectively explained 56.2% of the variation in species richness; precipitation contributed the most (44.1%). Our results provide valuable insights to improve the conservation of Lucanus and can contribute to furthering our understanding of the biogeography of stag beetles in China.

We describe the diversity of the stag beetle species and further explore its formation. The result indicated that the variables of geography vegetation, temperature, and precipitation collectively shaped the distributed pattern, and geographical variables are most important.     

Targeted and passive environmental DNA approaches outperform established methods for detection of quagga mussels,Dreissena rostriformis bugensis in flowing water

1. The early detection of invasive non‐native species (INNS) is important for informing management actions. Established monitoring methods require the collection or observation of specimens, which is unlikely at the beginning of an invasion when densities are likely to be low. Environmental DNA (eDNA) analysis is a highly promising technique for the detection of INNS—particularly during the early stages of an invasion.
2. Here, we compared the use of traditional kick‐net sampling with two eDNA approaches (targeted detection using both conventional and quantitative PCR and passive detection via metabarcoding with conserved primers) for detection of quagga mussel, Dreissena rostriformis bugensis, a high priority INNS, along a density gradient on the River Wraysbury, UK.
3. All three molecular tools outperformed traditional sampling in terms of detection. Conventional PCR and qPCR both had 100% detection rate in all samples and outperformed metabarcoding when the target species was at low densities. Additionally, quagga mussel DNA copy number (qPCR) and relative read count (metabarcoding) were significantly influenced by both mussel density and distance from source population, with distance being the most significant predictor.
4. Synthesis and application. All three molecular approaches were more sensitive than traditional kick‐net sampling for the detection of the quagga mussel in flowing water, and both qPCR and metabarcoding enabled estimates of relative abundance. Targeted approaches were more sensitive than metabarcoding, but metabarcoding has the advantage of providing information on the wider community and consequently the impacts of INNS.

     

量天尺根部内生真菌的多样性

为了解不同量天尺（火龙果）品种根部内生真菌菌群组成及多样性,采集GHL-1、GHL-2、GHL-3、ML-1和DL 5个量天尺品种健康根部样品,进行内生真菌分离,采用形态观察和ITS序列分析相结合的方法进行鉴定、归类。共分离得到内生真菌菌株117株,总体分离率为25.71%,分别隶属于13个属,其中Trichoderma、Fusarium、Chaetomium和Phoma为量天尺内生真菌的优势种群,分别占总菌株数的24.79%、35.04%、10.26%和10.26%;不同量天尺品种内生真菌的结构和组成存在一定差异,GHL-2、GHL-3和DL 3个品种中分离频率最高的内生真菌类群为Fusarium,GHL-1和ML-1分离频率最高的类群为Trichoderma;多样性分析结果反映出不同量天尺品种内生真菌菌群的多样性指数、丰富度指数和均匀度指数水平存在差异,其中GHL-2的3项指数均为最高。表明品种差异对内生真菌的组成和多样性均有影响。