Genomic atlases of introgression and differentiation reveal breeding footprints in Chinese cultivated rice

The long history of cultivation and breeding has left a variety of footprints in the genomes of Asian cultivated rice (Oryza sativa L.). In this study, we focus on two types of genomic footprints, introgression and differentiation, in a population of more than 1200 Chinese rice accessions. We found that a Xian/indica and a temperate Geng/japonica accession respectively contained an average of 19.3-Mb and 6.8-Mb alien introgressed chromosomal segments, of which many contained functional sequence variants, quantitative trait loci, or genes controlling flowering, grain, and resistance traits. Notably, we found most introgressions, including the known heterotic loci Hd3a and TAC1, were distributed differentially between the female and male parents of three-line indica hybrid rice, indicating their potential contribution to heterosis. We also found many differentiated regions between subgroups within a subpopulation contained agronomically important loci, such as DTH7, Hd1 for heading date, and qCT7 for cold tolerance, providing new candidates for studying local adaptation or heterosis. Tracing these footprints allows us to better understand the genetic exchange or differentiation underlying agronomic traits in modern Chinese rice cultivars. These findings also provide potential targets for rice genetic research and breeding.     

不同类型性诱剂诱芯及诱捕器组合对草地贪夜蛾诱集效果评价

本研究通过评价诱芯、诱捕器和诱芯组合的诱集效果,筛选出对草地贪夜蛾雄蛾诱捕效果最佳的诱芯和诱捕器组合,为草地贪夜蛾综合防控提供技术支持。诱芯优化筛选试验中,9种诱芯中编号为3-4、4-2、4-3的3种诱芯对草地贪夜蛾雄蛾诱捕效果最好,专一性强。诱捕器筛选试验中,5种市面上常见诱捕器里,桶型诱捕器是其他型诱捕器的诱捕效果2倍以上,效果最佳。诱芯筛选试验中,在使用桶型诱捕器及小夜蛾诱捕器的条件下,翔林3-3诱芯对草地贪夜蛾雄蛾的诱虫效果都为最佳。此研究为我国草地贪夜蛾的综合防治提供新途径。     

Redox‐modulated colorimetric detection of ascorbic acid and alkaline phosphatase activity with gold nanoparticles

Gold nanoparticles (AuNPs) exhibit characteristic absorption peaks in the ultraviolet visible region due to their special surface plasmon resonance effect. This characteristic absorption peak would change with the relative colour varying from wine red to orange‐yellow upon sequential addition of ascorbic acid (AA) into the mixture of AuNPs and Ag(I). Similar observations also could be found when the hydrolysis product of sodium l ‐ascorbyl‐2‐phosphate with alkaline phosphatase (ALP) was used as an alternative to AA. Results of structure characterization confirmed that the phenomena were due to the reduction of Ag(I) to Ag(0) on the surface of AuNPs and the formation of core‐shell AuNPs@Ag. Therefore, a colorimetric assay for rapid visual detection of AA and ALP based on redox‐modulated silver deposition on AuNPs has been proposed. Under the optimal experimental conditions, the absorbance variation ΔA_{522 nm}/A_{370 nm} of AuNPs was proportional to the concentration of AA (5–60 μmol/L) and ALP (3–18 U/L) with the corresponding detection limit of 2.44 μmol/L for AA and 0.52 U/L for ALP. The assay showed excellent selectivity towards AA and ALP. Moreover, the assay has been applied to detect AA and ALP activity in real samples with satisfying results.     

The abundance and diversity of gut bacteria of rice leaffolder Cnaphalocrocis medinalis (Guenée) across life stages

The bacterial community living in the insect gut may play an important role in nutrition, immunity and protection, detoxification of toxins, and inter- and intra-specific communication. Rice leaffolder Cnaphalocrocis medinalis (Guenée) (Lepidoptera: Crambidae) is a notorious pest in rice, and the diversity of the gut bacteria of C. medinalis across life stages are not well understood. Here, the diversity and abundance of the gut bacterial community in C. medinalis through life stages were investigated using Illumina Miseq technology. A total of 22 bacterial phyla, 42 classes, 100 orders, 179 families, 350 genera and 395 species were identified across the different life stages of C. medinalis. Proteobacteria and Firmicutes phyla were the dominant bacterial taxa. Members of the genera Enterococcus, unclassified Enterobacteriaceae, Wolbachia, Acinetobacter, Stenotrophomonas, Microbacterium, Bacillus, Corynebacterium, Lampropedia, and Sphingobacterium were found at all life stages. Enterococcus and unclassified Enterobacteriaceae occupied higher relative abundance among bacteria community in the 2nd to 5th instar larvae, pupae and adults. The structure of bacterial community differed across the life stages of C. medinalis. Our findings will enrich the understanding of gut bacteria in C. medinalis, and will provide foundation and assistance for the development of novel pest management strategies through utilization of microbiota.     

The use of three-dimensional model construction of virtual technology in orthopedic treatment

ObjectiveThe objective of this study is to explore the construction of a digital three-dimensional model of virtual technology that plays an auxiliary role in orthopedic treatment.MethodsThree fracture patients were selected, with no abnormality was observed in bone examination, no musculoskeletal disease in the past; and spiral CT scan of the spine and pelvis, upper limbs, and lower limbs was performed. The virtual technology was used to build a digital 3D model, mainly using the editing software Mimics10.0 software. In addition, the virtual three-dimensional model was verified by virtual surgery, data storage security, work efficiency of the model, model validity, three-dimensional characteristics of the model, the interaction mode of the model, and the data accuracy of the model were studied.ResultsThe digital 3D model was successfully established by Mimics10.0 software. The data fitting efficiency was very high. The data storage security of the 3D model was greatly improved compared with the 2D model, and the work efficiency was improved by at least 50%. There was also a significant change in the accuracy and interaction of data acquisition. Therefore, the detection of digital 3D model work through virtual surgery simulation fully demonstrated the positive auxiliary role of 3D model in orthopedic treatment.ConclusionThe digital 3D model based on Mimics10.0 software is efficient and accurate in obtaining data. It is very effective for subsequent adjuvant therapy in the field of orthopedics, reducing the probability of misdiagnosis by doctors, saving time and improving efficiency, reducing patient's physical pain and unnecessary economic expenses.     

2′-Functional group of adenosine in 10–23 DNAzyme promotes catalytic activity

10–23 DNAzyme is an artificially selected catalytic DNA molecule. Its great potential as genetic therapeutics promoted chemical modifications for more efficient DNAzymes. Here, 10–23 DNAzyme was modified on its six deoxyadenosine residues (A5, A9, A11, A12, A15 in the catalytic domain and A0 of the recognition arm next to the cleavage site) with compound 1, an adenosine analogue with 2′-O-[N-(aminoethyl)carbamoyl]methyl group. A positive effect of compound 1 at A15 was observed (HJDS-05, k_obs = 0.0111 min⁻¹). Compared to the effect of 2′-H and 2′-OMe at A15, this result provided an approach for more efficient DNAzyme by combining 2′-substituted amino group of adenosine with A15 as the lead structure.     

大兴安岭泥炭地不同菌根类型木本植物叶片凋落物分解及其温度敏感性差异

以我国大兴安岭多年冻土区泥炭地常见的3种外生菌根木本植物(细叶沼柳Salix rosmarinifolia、白桦Betula platyphylla和柴桦B.fruticosa)和4种欧石楠菌根木本植物(笃斯越桔Vaccinium uliginosum、狭叶杜香Ledum palustre、甸杜Chamaedaphne calyculata和小叶杜鹃Rhododendron parrifolum)为研究对象,通过315天培养试验测定10和20℃叶片凋落物分解过程中的碳(C)累积矿化量和重量损失,并分析其温度敏感性。结果表明:外生菌根植物叶片凋落物的C矿化量和重量损失在10和20℃均高于欧石楠菌根植物;外生菌根植物凋落物分解过程中C矿化量的温度敏感性系数高于欧石楠菌根植物,但重量损失的温度敏感性系数低于欧石楠菌根植物;在每一培养温度下,C矿化量和重量损失均与凋落物全氮(N)和全磷(P)浓度呈正相关,与C/N和C/P呈负相关;尽管C矿化量的温度敏感性系数与凋落物初始化学组成无显著相关性,但重量损失的温度敏感性系数与凋落物全N和全P浓度呈负相关,与C/N和C/P呈正相关。本研究结果为认识和预测气候变暖及其引起的物种组成变化对北方泥炭地植物凋落物分解的影响提供理论依据。     

长江三角洲核心区绿地系统时空演变特征及生态服务价值评估

在经济建设与环境保护矛盾突出的背景下,研究区域绿地系统时空演化特征,探讨人为因素对绿地系统生态服务的影响,对于改善绿地资源管理、促进区域永续协调发展具有重要意义。本研究基于景观生态学研究方法和生态服务价值当量因子评估法,运用ArcGIS 10.2软件的空间分析功能,对1990-2015年长江三角洲核心区绿地系统时空演化特征及生态服务价值进行了分析。结果表明:(1)长三角核心区绿地景观规模随时间的变化具有阶段性特征,呈现先扩大后缩减的态势;绿地景观与其他土地利用类型的转移存在阶段性与指向性特征;绿地景观格局总体上表现为初期集聚同质化、后期破碎异质化。(2)长三角核心区绿地系统生态服务价值随时间变化明显,不同绿地景观类型有不同的阶段性特征;长三角核心区绿地系统生态服务类型中,调节服务对于绿地系统整体生态服务价值贡献最大。(3)长三角核心区绿地系统生态服务价值在空间上呈现南北不均衡的特征,总体上呈南高北低态势,其中杭州市绿地系统生态服务价值在不同阶段均最高。区域地形地貌是影响区域生态服务价值的一个重要因素。