玫瑰色微球菌A-04的红色素鉴定及稳定性分析

从石油污染的土壤和水样中筛选出一株玫瑰色微球菌A-04 Micrococcus roseus,对其所产红色色素进行了分离,并初步鉴定了色素种类,基于对影响A-04色素稳定性的单因素分析基础之上,采用3因素3水平响应面分析法,进一步对影响色素稳定性的主要因素进行了优化分析。结果表明A-04所产红色色素为类胡萝卜素,对该菌株的色素稳定性的单因素条件分析,色素对环境条件的耐受性较好,在80℃、pH5. 0～8. 0等条件下依然能长时间保持鲜红而不褪色。经响应面优化分析表明:温度、pH和溶剂是影响该色素稳定性的主要因素,温度与溶剂的交互作用对色素稳定性的影响也较为明显。pH5. 0～8. 0之间时,在80℃范围内,温度越低,同时溶剂的极性越大,越有利于维持色素的稳定性。本研究结果为该色素的实际开发和应用奠定了基础。     

6A型肺炎球菌结合物分子大小对小鼠免疫原性的影响

目的 比较不同分子大小的6A型肺炎球菌(serotype 6A Streptococcus Pneumoniae )结合物和佐剂吸附在小鼠体内免疫原性的影响。方法 通过乙酸水解降低6A型荚膜多糖的相对分子质量制备成水解物,水解物经1-氰基-4-二甲胺基吡啶四氟硼酸盐(CDAP)活化并与破伤风类毒素己二酸酰肼衍生物TT AH 结合,制备成结合物。用Sepharose 4 Fast Flow 纯化结合物,并根据化学检测结果将结合物分为 K D 0.0~0.2、 K D 0.2~0.4、 K D 0.4~0.6等3个组分,每个组分分别以磷酸铝佐剂吸附,将吸附前后的各个组分按照每针次每只小鼠0.2 μg分别免疫小鼠,并采用ELISA检测结合物在小鼠体内的抗体水平。结果 3种不同相对分子质量吸附前后的结合物在小鼠体内均能产生较高水平的抗体,各组2、3针之间具有明显的加强效应。在吸附组和未吸附组中,3种不同分子大小的结合物在小鼠体内产生抗体水平无明显差异。各组分佐剂吸附后的结合物血清抗体滴度高于未吸附组,但这种差异无统计学意义( P > 0.05)。结论 结合物的分子大小对小鼠体内抗体水平的产生没有明显影响;磷酸铝佐剂吸附对于不同分子大小的结合物在小鼠体内的免疫原性有一定的增强效应,但这种增强效应差异无统计学意义。     

Identification of gravid mosquitoes from changes in spectral and polarimetric backscatter cross sections

Improving the survey of mosquito populations is of the utmost importance to further enhance mitigation techniques that protect human populations from mosquito‐borne diseases. While mosquito populations are generally studied using physical traps, stand‐off optical sensors allow to study insect ecosystems with potentially better spatial and temporal resolution. This can be greatly beneficial to eco‐epidemiological models and various mosquito control programs. In this contribution, we demonstrate that the gravidity of female mosquitoes can be identified from changes in their spectral and polarimetric backscatter cross sections. Among other predictive variables, the wing beat frequency and the depolarization ratio of the mosquito body allows for the identification of gravid females with a precision and recall of 86% and 87%, respectively. Since female mosquitoes need a blood meal to become gravid, statistics on gravidity is of prime importance as only females that have been gravid might carry infectious diseases. In addition, it allows to detect possible breeding habitat, predict a potential increase in the mosquito population and provide a better overall understanding of the ecosystem dynamics. As a result, targeted and localized mitigation techniques can be used, reducing the cost and improving the efficiency of mosquito population control.     

Changes in ecosystem services and an analysis of driving factors for China's Natural Forest Conservation Program

China's Natural Forest Conservation Program (NFCP) is aimed at improving the fragile and unstable ecological environment and has become one of the largest ecological restoration programs in the world because of its enormous investment and effects. It is important to work out and strengthen new measures to overcome difficulties to promote more ecosystem services and human well‐being in the NFCP. This study focused on how to evaluate the ecosystem services change brought about by implementing the NFCP. Taking the key state‐owned forest areas in the Northeast and Inner Mongolia as the study area, we provide a basic overview of development and construct an evaluation index system and a distributed calculation method for the NFCP to analyze the implications of the NFCP on ecosystem services combined with multi‐source data coupling. An evaluation index system for NFCP ecosystem services was constructed. The system includes five ecological service functions and 12 evaluation indices. The trade‐off and/or synergistic analysis of ecosystem services were carried out. The regional characteristics and changes in the NFCP ecosystem services were emphasized. Although it has not been implemented for a long time, the NFCP has had a great impact on ecosystem services because it reduces soil and water losses, increases soil fertility, strengthens the forest carbon sink and helped the forest accumulate nutrients and purify the atmosphere. Socioeconomic factors affect the NFCP ecosystem services, such as the implementation area of NFCP, investment amount of NFCP, area ratio of nature reserves, and yield of tree stock volume. Policy drivers of the NFCP, changes in the economic structure and reductions in forest yield are the main factors affecting the change in NFCP ecosystem services. Although the NFCP has positively affected the society, the economy, and the ecological environment, it has also generated some problems, such as the improper management of forest resources, shortage of capital investment, staff transfer, etc. The social and economic problems will be transient with implementation of the NFCP, and the structural changes in forestry and agriculture may eventually benefit the forestry workers and other stakeholders.     

围产期干细胞库质量管理体系构建

围产期干细胞库质量管理体系（QMS）建设是保障干细胞产品和服务健康发展的基础工作。本文比较分析美国输血协会（AABB）、细胞疗法认证基金会（FACT）和ISO 9001的标准的架构、内容和侧重点,重点论述围产期干细胞库QMS构建的方法、步骤和参考模式。参照权威机构标准建立和运行QMS,能够保障我国围产期干细胞库标准化、规范化和科学化的建设和管理,提升我国干细胞库能力和信任水平。良好的QMS进一步促进干细胞与精准医疗战略性新兴产业升级,为建设健康中国提供动力。     

Comparative expression analysis of heavy metal ATPase subfamily genes between Cd-tolerant and Cd-sensitive turnip landraces

The heavy metal ATPase(HMA)subfamily is mainly involved in heavy metal(HM)tolerance and transport in plants,but an understanding of the definite roles and mechanisms of most HMA members are still limited.In the present study,we identified 14 candidate HMA genes named BrrHMAl—BrrHMA8 from the turnip genome and analyzed the phylogeny,gene structure,chromosome distribution,and conserved domains and motifs of HMAs in turnip(Brassica rapa var.rapa).According to our phylogenetic tree,the BrrHMAs are divided into a Zn/Cd/Co/Pb subclass and Cu/Ag subclass.The BrrHMA members show similar structural characteristics within subclasses.To explore the roles of BrrHMAs in turnip,we compared the gene sequences and expression patterns of the BrrHMA genes between a Cd-tolerant landrace and a Cd-sensitive landrace.Most BrrHMA genes showed similar spatial expression patterns in both Cd-tolerant and Cd-sensitive turnip landraces;some BrrHMA genes,however,were differentially expressed in specific tissue in Cd-tolerant and Cd-sensitive turnip.Specifically,BrrHMA genes in the Zn/Cd/Co/Pb subclass shared the same coding sequence but were differentially expressed in Cd-tolerant and Cd-sensitive turnip landraces under Cd stress.Our findings suggest that the stable expression and up-regulated expression of BrrHMA Zn/Cd/Co/Pb subclass genes under Cd stress may contribute to the higher Cd tolerance of turnip landraces.     

Deciphering the global phylogeography of a coastal shrub (Scaevola taccada) reveals the influence of multiple forces on contemporary population structure

The phylogeography of coastal plant species is heavily influenced by past sealevel fluctuations, dispersal barriers, and life-history traits, such as long-distance dispersal ability of the propagules. Unlike the widely studied mangroves, phylogeographic patterns have remained mostly obscure for other coastal plant species. In this study, we sampled 42 populations of Scaevola taccada (Gaertn.) Roxb., a coastal shrub of the family Goodeniaceae, from 17 countries across its distribution range. We used five chloroplast DNA (cpDNA) and 14 nuclear microsatellite (simple sequence repeat [SSR]) markers to assess the influence of abiotic factors and population genetic processes on the phylogeographic pattern of the species. Geographical distribution of cpDNA haplotypes suggests that the species originated in Australia, followed by historical dispersal and expansion of its geographic range. Multiple abiotic factors, including the sealevel changes during the Pleistocene, the presence of landmasses like the Malay Peninsula, and contemporary oceanic circulation patterns, restricted gene flow between geographically distinct populations, thereby creating low haplotype diversity and a strong population structure. Population genetic processes acted on these isolated populations, leading to high nuclear genetic diversity and population differentiation, as revealed from analyzing the polymorphic SSR loci. Although genetic divergence was mostly concordant between cpDNA and SSR data, asymmetrical gene flow and ancestral polymorphism could explain the discordance in the detailed genetic structure. Overall, our findings indicate that abiotic factors and population genetic processes interactively influenced the evolutionary history and current phylogeographic pattern of S. taccada across its distribution range.     

Transient expression of a TaGRF4-TaGIF1 complex stimulates wheat regeneration and improves genome editing

Science China Life Sciences - Genome editing is an unprecedented technological breakthrough but low plant regeneration frequencies and genotype dependence hinder its implementation for crop...