Forest responses to the large-scale east coast fires in Korea

The east coast forest fires of April 2000 were Koreas largest recorded fires. This, along with the fact that they took place in the region most frequently affected by fire, attracted a great deal of attention. Due to the variations in wind, topography and pre-fire forest stands, a heterogeneous landscape mosaic of burn severity was created across the region. It turned out to be an excellent opportunity to study various landscape-scale impacts of fires on forest dynamics. Therefore, we investigated stands in the 23794ha of burned forest region, in terms of burn severity, vegetation regeneration and forested landscape change as a measure of community stability. Using the geographic information system technique, we analyzed the differential severity and post-fire recovery of pre-fire forest types of different stand age both at stand and species level. Analysis showed that pre-fire vegetation was composed of mainly pine (Pinus densiflora) stands that occupied 70% of the whole forested area, while pine-hardwood and hardwood stands occupied only 28% and 3%, respectively. In addition, two-thirds of all stands were less than 30-years-old. Pine stands were the most severely burned, while conversely pine-hardwood and hardwood stands were less vulnerable. This implied that pine forests had fire-prone characteristics. Vegetation recovery went the opposite way; that is, the regenerating vegetation cover was 71% at pre-fire hardwood stands, and 65% and 53% at pine-hardwood and pine stands, respectively. However, these recovery rates were strikingly fast, considering that investigation took place about 3months after the fires. Fire did not initiate successional processes, but tended to accelerate the predicted successional changes by releasing pre-fire understory species that survived the fires and regenerated by sprouting. The dominant pre-fire tree species (P. densiflora) was susceptible to fire and not resilient enough to reestablish in competition with oak species. Contrary to pines, the abilities of oak species, mainly Quercus mongolica and Q. variabilis, to survive fires and to resprout vigorously made them dominant at most post-fire stands. These shifts in species abundance caused drastic changes to the landscape: from pine-dominated to oak-dominated stands without any notable change in species composition. The patterns in forest regeneration that we observed in Korea may be representative of forest responses to any long-term repeated disturbances, including fire.     

循环microRNAs的外泌形成机制及其对乳腺癌侵袭和转移的影响

目前乳腺癌的临床诊疗主要依赖影像学和相对较少的预后/预测指标(如雌激素受体、孕激素受体、HER2等).这些生物标志物主要是基于原发肿瘤病灶的生物学检测,可用于转移或复发的检测指标很少,尤其是在切除肿瘤原发灶后,复发监测很困难.循环cell-free microRNAs(circulating cf-miRNAs,或简称circulating miRNAs)的发现为改变现有乳腺癌临床诊疗模式提供了可能.Cell-free miRNA通过外泌体、微囊或转运蛋白的主动外泌机制,可能在循环miRNA的形成中起着重要作用.Cell-free miRNA特别是circulating miRNA不仅自身可以作为信号分子影响肿瘤细胞和组织微环境,而且还可以与其他信号通路发生交互通讯来调控肿瘤部位新生血管的形成和肿瘤细胞表型的上皮-间质转换,影响乳腺癌的侵袭和转移.本文综述了循环miRNA的特征与分泌机制,特别是乳腺癌相关的循环miRNA参与作为一种液体活检生物标志物在乳腺癌诊断、预后评价和疗效评估的临床意义.     

The necessity for low temperature treatment on the eggs of Emma Cricket,Teleogryllus emma and the method of increasing the hatching rate after low temperature treatment

The necessity for low temperature treatment of Emma Cricket Eggs, Teleogryllus emma, to dormancy breaking and the method of increasing hatching rate after low temperature treatment were investigated. Emma Cricket Eggs were treated by constant temperature, room temperature, low temperature, step‐down low temperature. As a result, constant temperature treatment was the lowest on hatching rate. The hatching rates of the rest of other temperature treatments were not different statistically (one‐way ANOVA). In other word, low temperature treatment was not necessary to dormancy breaking. But low temperature treatment was necessary to control individual number of Emma Cricket, Teleogryllus emma, on the mass indoor‐rearing system. And the step‐up temperature treatment was necessary to increase hatching rate after low temperature treatment.     

Cysteine and glutathione in orange juice

The major part of the sulfhydryl compounds of both Valencia and Navel orange juice was found to exist as cysteine and glutathione. These two compounds were isolated and analyzed as their crystalline S-benzyl derivatives from concentrates prepared by preferential mercuric ion precipitation. Cysteine analysis before and after hydrolysis showed that all of the sulfhydryl of the concentrates was cysteine and glutathione. The glutathione analysis was confirmed by Woodward's glyoxalase method.     

公园水体浮游植物与环境因子的关系

于2006年10月—2007年9月,对上海市10个公园景观水体水质环境因子及浮游植物群落结构进行逐月监测,应用主成分分析(PCA)和典范对应分析(CCA)探讨了浮游植物数量与水质环境因子之间的关系,评价了城市水环境状况,以期为公园水体的水质管理提供科学依据。结果表明:共鉴定公园水体浮游植物8门167种,浮游植物丰度范围为2.16×106～7.87×106cells·L-1,主要以蓝藻、硅藻、绿藻为主,优势种由皮状席藻(Phormidium corium)、窝形席藻(Ph.fovedarum)、微小平裂藻(Merismopedia tenuissima)、尖针杆藻(Synedraacus)、银灰平裂藻(M.glauca)、啮蚀隐藻(Cryptomonas erosa)等组成;公园景观水体水温变幅为7.9～29℃,水深0.79～1.05m,透明度0.5～0.70m,总氮0.896～3.9mg·L-1,铵氮0.224～1.979mg·L-1,硝酸盐0.126～0.346mg·L-1,亚硝酸盐0.015～0.140mg·L-1,总磷0.063～0.372mg·L-1,活性磷0.007～0.194mg·L-1,化学需氧量为5.418～10.685mg·L-1。PCA分析表明,水温、透明度、氮磷营养因子以及化学需氧量是影响浮游植物密度变化的主要因素。CCA分析表明,总氮、总磷、透明度和水温是影响浮游植物群落结构季节变化的主要驱动因子。     

贵州省8个自然保护区两栖动物分布研究

报道了贵州省8个自然保护区55种两栖动物,讨论两栖动物在贵州省的地理经度替代、纬度替代和垂直替代特点。结果表明,水平分布范围广的种类,垂直分布范围也较广。     

Characterization of 30 new microsatellite markers,developed from enriched genomic DNA library of zoysiagrass Zoysia japonica Steud.

The present study reports the development of 30 polymorphic microsatellite markers for zoysiagrass Zoysia japonica Steud. The 30 markers produced a total of 125 alleles with an average of 4.2 alleles per locus. Values for observed and expected heterozygosities ranged from 0.10 to 0.95 and from 0.15 to 0.81, respectively. At significance threshold (P < 0.05), 11 loci deviated from Hardy–Weinberg equilibrium, whereas significant linkage disequilibrium values were observed between 16 pairs of loci. These markers may provide information needed to select genetically diverse parents for developing breeding and mapping populations of zoysiagrass.     

Local climate mediates spatial and temporal variation in carabid beetle communities in three forests in Mount Odaesan,Korea

1. Global environmental change can dramatically alter the composition of floral and faunal communities, and elucidating the mechanisms underlying this process is important for predicting its outcomes. Studies on global climate change have mostly focused on statistical summaries within wide spatial and temporal scales; less attention has been paid to variability in microclimates at narrower spatial and temporal scales. 2. The microclimate is the suite of climatic conditions measured in a local area. Environmental variables at the microclimatic scale can be critical for the ecology of organisms inhabiting each area. The effect of spatial and temporal changes in the microclimate on the ecology of carabid beetle communities in three sites on Mount Odaesan, Korea was examined. 3. Carabid beetle communities and quantified site‐specific environmental factors from measurements of air temperature, air humidity, light intensity and soil temperature over 5 years (2010–2015) were surveyed. 4. It was found that microclimatic variables and the patterns of temporal changes in carabid beetle communities differed between the three sites within the single mountain system. Microclimatic variables influencing temporal changes in beetle communities also differed between the sites. Therefore, it is suggested that variation in local microclimates affects spatial and temporal variation in carabid beetle communities at a local scale. 5. The present results demonstrate the importance of regular surveys of communities at local scales. Such surveys are expected to reveal an additional fraction of variation in communities and underlying processes that have been overlooked in studies of global community patterns and change.     

The plastidic Arabidopsis protoporphyrinogen IX oxidase gene, with or without the transit sequence, confers resistance to the diphenyl ether herbicide in rice

Agrobacterium‐mediated gene transformation was used to introduce plastidic protoporphyrinogen IX oxidase (Protox) genes from Arabidopsis, with and without the transit sequence, into the rice genome. They were placed under the control of the constitutive and ubiquitous maize ubiquitin promoter, and their abilities to confer resistance to the diphenyl ether‐type herbicide, oxyfluorfen were compared. The integration and expression of the transgene in the T₁ generation was examined by Southern, northern and western blot analyses. Surprisingly, as judged by an in vivo seed germination assay and an in vitro cellular leakage assay, both lines were similarly resistant to oxyfluorfen. The tolerance to cellular damage (lipid peroxidation and electrolyte leakage) was higher in transgenic plants than in wild‐type plants. In transgenic plants, the degree of herbicide resistance varied directly with the absolute amount of Protox protein expression. Both the intact protein and the protein with the transit sequence deleted were accumulated in plastids.