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1.
Reconstruction of the grapevine cultivation history has advanced tremendously during the last decade. Identification of grapevine cultivars by using microsatellite DNA markers has mostly become a routine. The parentage of several renowned grapevine cultivars, like Cabernet Sauvignon and Chardonnay, has been elucidated. However, the assembly of a complete grapevine genealogy is not yet possible because missing links might no longer be in cultivation or are even extinct. This problem could be overcome by analyzing ancient DNA from grapevine herbarium specimens and other historical remnants of once cultivated varieties. Here, we present the first successful genotyping of a grapevine herbarium specimen and the identification of the corresponding grapevine cultivar. Using a set of nine grapevine microsatellite markers, in combination with a whole genome amplification procedure, we found the 90-year-old Tribidrag herbarium specimen to display the same microsatellite profile as the popular American cultivar Zinfandel. This work, together with information from several historical documents, provides a new clue of Zinfandel cultivation in Croatia as early as the beginning of fifteenth century, under the native name Tribidrag. Moreover, it emphasizes substantial information potential of existing grapevine and other herbarium collections worldwide.  相似文献   

2.
Maternal contamination of fetal DNA represents a major problem when highly sensitive molecular techniques are used in the prenatal diagnosis of genetic diseases. For this reason, we have studied the possibility of using DNA isolated from syncytiotrophoblast vesicles as a target of gene amplification (PCR). Three PCR systems were selected which included a repetitive 149 bp fragment of the Y chromosome, the VNTR locus D1S80, and a portion of the β-globin gene. The results of these experiments indicate that DNA isolated from syncytiotrophoblast vesicles is free of maternal contamination and is suitable for gene amplification and DNA analysis.  相似文献   

3.
Y-chromosome-specific DNA amplified in ancient human bone   总被引:2,自引:0,他引:2  
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4.
Evolutionary biologists are increasingly relying on ancient DNA from archaeological animal bones to study processes such as domestication and population dispersals. As many animal bones found on archaeological sites are likely to have been cooked, the potential for DNA preservation must be carefully considered to maximise the chance of amplification success. Here, we assess the preservation of mitochondrial DNA in a medieval cattle bone assemblage from Coppergate, York, UK. These bones have variable degrees of thermal alterations to bone collagen fibrils, indicative of cooking. Our results show that DNA preservation is not reliant on the presence of intact collagen fibrils. In fact, a greater number of template molecules could be extracted from bones with damaged collagen. We conclude that moderate heating of bone may enhance the retention of DNA fragments. Our results also indicate that ancient DNA preservation is highly variable, even within a relatively recent assemblage from contexts conducive to organic preservation, and that diagenetic parameters based on protein diagenesis are not always useful for predicting ancient DNA survival.  相似文献   

5.
Exclusion of β-thalassaemia in mice was undertaken by pre-implantation DNA diagnosis. Biopsies of approximately five cells were obtained from mouse pre-embryos. DNA prepared from this material was amplified by the polymerase chain reaction (PCR), enabling identification of the normal β-major globin gene in 11 out of 20 cases where it was known to be present. The expected negative result was obtained in 14 out of 16 homozygous thalassaemic embryos, with two false positives. Results are promptly available following PCR, thereby facilitating re-implantation of embryos which have had homozygous β-thalassaemia excluded. The mouse model illustrates a useful approach to pre-implantation diagnosis of genetic disease in the human.  相似文献   

6.
Plants have been used as good bio-indicators and genetic toxicity of environmental pollution in recent years. In this study, aquatic plants Hydrilla verticillata and Ceratophyllum demersum treated with 10 μmol/L Cd, 5 μmol/L Hg, and 20 μmol/L Cu for 96 h, showed changes in chlorophyll, protein content, and in DNA profiles. The changes in DNA profiles included variation in band intensity, presence or absence of certain bands and even appearance of new bands. Genomic template stability test performed for the ...  相似文献   

7.
In this study, we describe a simple strategy to detect β-thalassaemia mutations in prospective parents and to make prenatal diagnosis in pregnancies at risk in the Mediterranean population. Screening of prospective parents is carried out by dot blot analysis on enzymatically amplified DNA with a set of oligonucleotide probes complementary to the most common mutations in this population. Prenatal diagnosis is accomplished by the same procedure on enzymatically amplified amniocyte or trophoblast DNA. The main advantages of this procedure are the simplicity, sensitivity (0.05 μg of DNA), and rapidity (12–24 h). Further simplification is obtained by amplification of the DNA from crude amniotic cell lysate. The very low amount of fetal material necessary for this analysis eliminates the need to culture amniotic fluid cells and may decrease the fetal loss rate associated with trophoblast sampling. The number of specific DNA sequences obtained by the amplification procedure allowed us to use non-radioactive labelled oligonucleotide probes, which have several advantages compared to radioactive probes.  相似文献   

8.
This paper addresses a measurement of corporate environmental performance, and its application to the analysis of efficiency in the petroleum firms. In order to measure firms' environmental performance, we suggest a framework called “Gscore” that consists of five categories, namely general environmental management (GEM), input, process, output, and outcome. Gscore is a proxy measure of corporate environmental performance based on voluntary environment, health, and safety (EHS) report and is calculated by aggregating the points of the above five-categories. We apply our measurement framework to the data of 39 firms' voluntary EHS reports which are available on the internet. Ten of them, on which efficiency analysis was conducted with Gscore, assets, employee, and profits, are in petroleum and refining industry. According to our results: (1) a gap is found between rhetoric and practical environmental management stemming from calculating the relation between GEM and data part in 39 EHS reports. (2) On the whole, EHS reports of petroleum firms have something in common, but there are significant differences in the type and amounts of disclosed data among the EHS reports. (3) From the results of efficiency analysis, it is found that the number of employee exerts a considerable influence on determining the relative efficiency of petroleum firms, then Gscore, profits, and assets in sequence. Furthermore, Exxon, Ashland, Phillips Petroleum, and ARCO are shown to be efficient among 10 petroleum firms.  相似文献   

9.
何伟  王语苓 《环境科学学报》2021,41(11):4760-4770
基于数据包络法的超效率SBM模型、DEA-Malmquist指数、泰尔指数、变异系数和Tobit回归模型,对黄河流域54个地级以上城市的市辖区水资源利用效率、区域差异和影响因素展开测算和分析.结果表明:①2007-2017年,黄河流域城市水资源利用效率远未达到有效水平,82.6%的城市水资源利用效率普遍处于生产前沿面之下,存在水资源配置效率低下和资源浪费、冗余问题;城市水资源利用效率平均值由0.469缓慢波动上升为0.540,区域差异逐渐缩小,总体上呈现黄河上游 > 黄河下游 > 黄河中游的态势.②黄河上游、中游城市水资源利用全要素生产率整体处于上升阶段,下游地区城市水资源利用全要素生产率却处于下降阶段,影响黄河流域城市水资源利用全要素生产率的主要因素在于纯技术效率.③经济发展水平、产业结构等与水资源利用效率呈正相关;市场化程度、水资源禀赋与水资源利用效率的相关性不显著;水效管理政策、水污染物排放与水资源利用效率呈现较为显著的负相关关系.  相似文献   

10.
王晶  徐海 《地球环境学报》2022,13(2):132-162
广泛分布的湖泊为连续沉积和保存历史时期多样化生物核酸分子提供了绝佳的自然档案。随着近年来古DNA提取和测序技术的进步以及组学技术的发展,利用湖泊沉积物古DNA重建古生态演化及其对气候变化和人类活动的差异性响应得到广泛而深入的研究。本文回顾了古DNA研究的历史背景、理论基础,以及湖泊沉积物古DNA保存的影响因素和生物信息学分析流程;重点评述了湖泊沉积物古DNA在揭示气候环境变化、生物多样性及流域生态系统演化、物种定殖与外来物种入侵、人类活动影响、环境生态功能基因演化及其在细胞器基因组和古生态时间序列分析研究中的诸多应用和进展。同时还介绍了当前研究面临的局限和挑战以及组学技术在古DNA研究中的发展概况,分析了当前研究尚存的不足,并展望了未来可能的努力方向。  相似文献   

11.
中国生态效率的空间格局与影响机制分析   总被引:2,自引:1,他引:1  
实现经济增长的生态友好模式转变是当代中国建设两型社会的必然要求,而中国地区生态效率的空间格局及影响因素分析是地理学研究的重要问题.基于此,本文利用随机前沿模型测算2004—2012年间我国地区生态效率,其次,基于探索性空间分析技术对生态效率的空间关联特征进行分析,最后,借助空间计量经济模型对区域生态效率的影响因素进行分析.结果表明:中国地区生态效率总体呈上升趋势,但效率水平偏低,东部地区生态效率高于中西部地区;生态效率空间分异格局显著,且具有正向的空间相关性,其中,低-低生态效率区域集聚分布于我国西部内陆,高-高生态效率集聚区分布于东南沿海;空间面板回归显示,城市化水平及经济发展的提高有助于区域生态效率的提高,环境法规的实施及有效的环境监管可以确保生态安全,而第二、三产业比重的增加不利于生态效率的提高.  相似文献   

12.
AO与AAO工艺去除雌激素效能对比及分析   总被引:1,自引:0,他引:1  
为探讨不同污水处理工艺对雌激素类有机物的处理效能,本研究设计并同时运行了AO和AAO两种污水处理工艺,在稳定运行条件下,比较了两种工艺对各种常规水质指标和雌激素的去除状况.试验结果表明,AAO系统对污染物去除效能明显优于AO系统.AAO对COD、TN、NH4+-N、TP及TOC的去除效能分别比AO高出7.55%、20....  相似文献   

13.
We report on dental and mandibular pathology in Labidosaurus hamatus, a 275 million-year-old terrestrial reptile from North America and associate it with bacterial infection in an organism that is characterized by reduced tooth replacement. Analysis of the surface and internal mandibular structure using mechanical and CT-scanning techniques permits the reconstruction of events that led to the pathology and the possible death of the individual. The infection probably occurred as a result of prolonged exposure of the dental pulp cavity to oral bacteria, and this exposure was caused by injury to the tooth in an animal that is characterized by reduced tooth replacement cycles. In these early reptiles, the reduction in tooth replacement is an evolutionary innovation associated with strong implantation and increased oral processing. The dental abscess observed in L. hamatus, the oldest known infection in a terrestrial vertebrate, provides clear evidence of the ancient association between terrestrial vertebrates and their oral bacteria.  相似文献   

14.
The industrial sector is the biggest electricity consumer in Malaysia. Electric motors account for more than 45% of the electricity consumption in the industrial sector in the country. Therefore, it is very important to implement energy efficiency standards for electric motors to reduce energy consumption growth in this sector. This paper attempts to calculate the cost efficiency analysis and emission reduction by implementing energy efficiency standards for electric motor in Malaysia. The energy efficiency standards are proposed based on the efficiency of electric motors from survey data. The study examines the potential energy, economical and environmental impacts of the implementation of energy efficiency standards for electric motors in three scenarios i.e. 0.5%, 1.0% and 1.5% of standards efficiency improvement. Standards also enable consumers to reduce their electricity bill and contribute to a positive environmental impact.  相似文献   

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17.
为探究深水水库沉积物微生物功能特征及利用价值,于2019年在实验室对小湾水库表层沉积物微生物进行了驯化分离,并分析了其中一株细菌的脱氮效率.结果表明,分离出的细菌XW731经鉴定属于假单胞菌属(Pseudomonas sp.),是一种贫营养型好氧反硝化菌;在分别以NH4+-N、NO3--N和NO2--N为唯一氮源时,该菌对NH4+-N、NO3--N和NO2--N去除率分别为33.6%、68.5%和9.1%;以NH4+-N和NO3--N为氮源时,对NH4+-N和NO3--N去除率分别为66.4%、89.6%,同步硝化反硝化能力更强.将该菌投加到两种城市微污染水体后测试表明,该菌对城市河道水体的NH4+-N和NO3--N去除率分别为38.3%和42.4%,对城市降雨水体的NH4+-N和NO3--N去除率分别为22.2%和7.7%.  相似文献   

18.
区域碳排放效率评价及影响因素分析   总被引:1,自引:0,他引:1  
李健  马晓芳  苑清敏 《环境科学学报》2019,39(12):4293-4300
以长三角、珠三角与京津冀三大经济圈为研究对象,运用考虑非期望产出SBM模型、Malmquist全要素生产率指数模型分析碳排放效率的静态、动态变化特征和差异性,并进一步探讨三大经济圈碳排放效率影响因素的作用效果.结果表明,2007—2016年间三大经济圈的碳排放效率整体上水平较低,三大经济圈碳排放效率在时序上的变动都经历了高值波动、持续下降和低值波动阶段.从Malmquist指数分解情况来看,技术退步是全要素生产率下降的主要原因,规模效率存在不足,全要素生产率整体水平有待提高,碳排放效率提升空间巨大.地区产业结构、能源利用效率、外资依存度、城市化水平等因素对三大经济圈的碳排放效率影响显著,技术进步水平与其他因素相比对碳排放效率的影响效果并不明显.  相似文献   

19.
Solution 31P nuclear magnetic resonance spectroscopy (31P-NMR) is a useful method to analyze organic phosphorus (Po), but a general procedure for the analysis method is lacking. The authors used solution 31P-NMR, which was found to be an effective method for analysis of Po in Haihe River sediment, to analyze the Po in the surface sediment in Eastern China at the regional scale, and found that the NaOH-ethylenediaminetetraacetic acid (EDTA) extraction rate was affected by environmental factors. At the regional scale, the extraction rate showed a positive relationship with loss on ignition, when the extraction rate was lower than 60%. The extraction rate had no relationship with the loss on ignition when the extraction rate was higher than 60%. The extraction rate showed a negative relationship with pH, which means that the extraction rate was higher in acidic sediment and lower in alkaline sediment. The ratio of TC/TN (the ratio of total carbon to total nitrogen) was considered to represent the origin of organic matter in the sediment. The extraction rate was high when the TC/TN ratio was lower than 20, meanwhile the extraction rate decreased as the TC/TN ratio increased. The results show that the origin of organic matter in sediment significantly affects the NaOH-EDTA extraction rate. This study will give theoretical support for building an effective and general solution 31P-NMR analysis method.  相似文献   

20.
对一株Phaeocystisglobosa的28SrDNA基因序列测定,共得到碱基大小为1795bp的两个序列片段,其中序列一的长度为970bp,序列二的长度为825bp。将Ph.globosa与Ph.antarctica和Prymnesiumpatelliferum同源序列进行对比,发现Ph.globosa与Ph.antarctica仅在序列二中有一个碱基插入/缺失,同源性为99.99%,而与Pr.patelliferum相比,有7处插入/缺失,碱基总变异率为6.13%;研究发现序列一中有一个比较明显的高度保守区和两个高变区;序列二中有两个比较明显的高变区、一个保守区和一个高度保守区。对28SrDNA基因RNA二级结构分析发现,DNA序列保守区在RNA二级结构上也非常保守,与DNA序列分析结果一致,都证明28SrDNA基因只适用于种以上水平的分类研究,不宜用于种间和种下水平的研究。  相似文献   

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