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101.
A. Laperche Y. Aigu M. Jubault M. Ollier S. Guichard P. Glory SE. Strelkov A. Gravot MJ. Manzanares-Dauleux 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(4):669-684
Key message
Nitrogen levels can modulate the effectiveness of clubroot resistance in an isolate- and host-specific manner. While the same QTL were detected under high and low nitrogen, their effects were altered.Abstract
Clubroot, caused by Plasmodiophora brassicae, is one of the most damaging diseases of oilseed rape and is known to be affected by nitrogen fertilization. However, the genetic factors involved in clubroot resistance have not been characterized under nitrogen-limiting conditions. This study aimed to assess the variability of clubroot resistance under different nitrogen levels and to characterize the impact of nitrogen supply on genetic resistance factors. Linkage analyses and a genome-wide association study were conducted to detect QTL for clubroot resistance and evaluate their sensitivity to nitrogen. The clubroot response of a set of 92 diverse oilseed rape accessions and 108 lines derived from a cross between ‘Darmor-bzh’ (resistant) and ‘Yudal’ (susceptible) was studied in the greenhouse under high- and low-nitrogen conditions, following inoculation with the P. brassicae isolates eH and K92-16. Resistance to each isolate was controlled by a major QTL and a few small-effects QTL. While the same QTL were detected under both high and low nitrogen, their effects were altered. Clubroot resistance to isolate eH, but not K92-16, was greater under a low-N supply versus a high-N supply. New sources of resistance were found among the oilseed rape accessions under both low and high-N conditions. The results are discussed relative to the literature and from a crop improvement perspective.102.
Leonardo Restivo Bjrn Gerlach Michael Tsoory Lior Bikovski Sylvia Badurek Claudia Pitzer Isabelle C KosBraun AnneLaure MJ MaussetBonnefont Jonathan Ward Michael Schunn Lucas PJJ Noldus Anton Bespalov Vootele Voikar 《EMBO reports》2021,22(12)
Academic Core Facilities are optimally situated to improve the quality of preclinical research by implementing quality control measures and offering these to their users. Subject Categories: Methods & Resources, Science Policy & PublishingDuring the past decade, the scientific community and outside observers have noted a concerning lack of rigor and transparency in preclinical research that led to talk of a “reproducibility crisis” in the life sciences (Baker, 2016; Bespalov & Steckler, 2018; Heddleston et al, 2021). Various measures have been proposed to address the problem: from better training of scientists to more oversight to expanded publishing practices such as preregistration of studies. The recently published EQIPD (Enhancing Quality in Preclinical Data) System is, to date, the largest initiative that aims to establish a systematic approach for increasing the robustness and reliability of biomedical research (Bespalov et al, 2021). However, promoting a cultural change in research practices warrants a broad adoption of the Quality System and its underlying philosophy. It is here that academic Core Facilities (CF), research service providers at universities and research institutions, can make a difference.It is fair to assume that a significant fraction of published data originated from experiments that were designed, run, or analyzed in CFs. These academic services play an important role in the research ecosystem by offering access to cutting‐edge equipment and by developing and testing novel techniques and methods that impact research in the academic and private sectors alike (Bikovski et al, 2020). Equipment and infrastructure are not the only value: CFs employ competent personnel with profound knowledge and practical experience of the specific field of interest: animal behavior, imaging, crystallography, genomics, and so on. Thus, CFs are optimally positioned to address concerns about the quality and robustness of preclinical research. 相似文献
103.
Mirjam MJ Jacobs Ronald G van den Berg Vivianne GAA Vleeshouwers Marcel Visser Rolf Mank Mariëlle Sengers Roel Hoekstra Ben Vosman 《BMC evolutionary biology》2008,8(1):145
Background
The secondary genepool of our modern cultivated potato (Solanum tuberosum L.) consists of a large number of tuber-bearing wild Solanum species under Solanum section Petota. One of the major taxonomic problems in section Petota is that the series classification (as put forward by Hawkes) is problematic and the boundaries of some series are unclear. In addition, the classification has received only partial cladistic support in all molecular studies carried out to date. 相似文献104.
WS Watkins R Thara BJ Mowry Y Zhang DJ Witherspoon W Tolpinrud MJ Bamshad S Tirupati R Padmavati H Smith D Nancarrow C Filippich LB Jorde 《BMC genetics》2008,9(1):1-17
Background
Major population movements, social structure, and caste endogamy have influenced the genetic structure of Indian populations. An understanding of these influences is increasingly important as gene mapping and case-control studies are initiated in South Indian populations.Results
We report new data on 155 individuals from four Tamil caste populations of South India and perform comparative analyses with caste populations from the neighboring state of Andhra Pradesh. Genetic differentiation among Tamil castes is low (RST = 0.96% for 45 autosomal short tandem repeat (STR) markers), reflecting a largely common origin. Nonetheless, caste- and continent-specific patterns are evident. For 32 lineage-defining Y-chromosome SNPs, Tamil castes show higher affinity to Europeans than to eastern Asians, and genetic distance estimates to the Europeans are ordered by caste rank. For 32 lineage-defining mitochondrial SNPs and hypervariable sequence (HVS) 1, Tamil castes have higher affinity to eastern Asians than to Europeans. For 45 autosomal STRs, upper and middle rank castes show higher affinity to Europeans than do lower rank castes from either Tamil Nadu or Andhra Pradesh. Local between-caste variation (Tamil Nadu RST = 0.96%, Andhra Pradesh RST = 0.77%) exceeds the estimate of variation between these geographically separated groups (RST = 0.12%). Low, but statistically significant, correlations between caste rank distance and genetic distance are demonstrated for Tamil castes using Y-chromosome, mtDNA, and autosomal data.Conclusion
Genetic data from Y-chromosome, mtDNA, and autosomal STRs are in accord with historical accounts of northwest to southeast population movements in India. The influence of ancient and historical population movements and caste social structure can be detected and replicated in South Indian caste populations from two different geographic regions. 相似文献105.
Stavropoulos-Kalinoglou A Metsios GS Panoulas VF Douglas KM Nevill AM Jamurtas AZ Kita M Koutedakis Y Kitas GD 《Arthritis research & therapy》2008,10(3):R59
Introduction
Rheumatoid arthritis (RA) is associated with altered metabolism leading to muscle wasting. In the general population, cigarette smoking is known to affect body composition by reducing fat and inhibiting muscle synthesis. Even though smoking has been implicated in the pathophysiology and progression of RA, its possible effects on body composition of such patients have not been studied. This cross-sectional study aimed to identify potential associations of smoking with body weight and composition of RA patients. 相似文献106.
107.
目的: 由于传统呼吸调控环路忽略了对血液循环的决定性作用,肺(静脉)血管容量相关研究甚少,亟需建立肺血管容量测量方法。方法: 选择正常志愿者完成CT全肺扫描,图像数据经过计算机软件分析处理,从肺尖到肺底以40~50层进行肺野手工切划,相邻层间由计算机自动模拟连接,在去除干扰后进行全肺血管(≥0.6 mm)高精度三维立体成像技术处理,进而计算全肺和肺血管容积。结果: 12例正常志愿者从肺尖到肺底CT扫描图片层数为530±98(431~841)张。全肺和肺血管的总容积是3705±857(2398~5383)ml ,肺血管血液总的容积是125±32(94~201)ml。按肺静脉系统血管容量约为全肺血管血液容量一半计算,应该是63±16(47~100)ml。结论: 肺CT扫描数据分析三维立体成像建立肺血管容量无创测量方法精确可行。 相似文献
108.
López-Calderón MJ U Figueroa-Viramontes M Fortis-Hernández G Núñez-Hernández E Ochoa-Martínez JI Sanchez-Duarte 《Phyton》2015,84(1):8-13
An experiment with increasing rates of fertilizer and manure in silage corn was established to evaluate the agronomic crop response and to estimate the manure nitrogen availability. The treatments were designed to deliver 0, 67, 100 and 133% of the crop nitrogen requirements (CNR), using ammonium sulphate and manure as N source. Dry matter (DM) yield was similar among treatments receiving N, but those values were greater than those found in the control. Nitrogen extraction at harvest was not statistically different in treatments with fertilizer or manure, but it was higher in these treatments than in the control without N (p≤ 0.05). With both sources of N, crop N extraction was adjusted to a quadratic regression equation, as a function of N rates. According to the fertilizer equivalence (EF) methodology, the rate of 231.3 kg/ha of inorganic fertilizer N, and 752.9 kg/ha of total N in manure, had 129.5 kg/ha of N extracted by the crop. The ratio of the above rates, fertilizer N/ manure total N, represents the crop available manure N; in the present study, it was 30.7% of total N in the manure. Since no differences in yield were observed between N sources, it is concluded that N fertilizer can be substituted by manure, at a rate estimated to provide the crop N requirements. The estimation of the manure available N is important to adjust manure rates, thereafter avoiding excessive applications and pollution risks. 相似文献
109.
110.
I.M. Parker D. Simberloff W.M. Lonsdale K. Goodell M. Wonham P.M. Kareiva M.H. Williamson B. Von Holle P.B. Moyle J.E. Byers L. Goldwasser 《Biological invasions》1999,1(1):3-19
Although ecologists commonly talk about the impacts of nonindigenous species, little formal attention has been given to defining what we mean by impact, or connecting ecological theory with particular measures of impact. The resulting lack of generalizations regarding invasion impacts is more than an academic problem; we need to be able to distinguish invaders with minor effects from those with large effects in order to prioritize management efforts. This paper focuses on defining, evaluating, and comparing a variety of measures of impact drawn from empirical examples and theoretical reasoning. We begin by arguing that the total impact of an invader includes three fundamental dimensions: range, abundance, and the per-capita or per-biomass effect of the invader. Then we summarize previous approaches to measuring impact at different organizational levels, and suggest some new approaches. Reviewing mathematical models of impact, we argue that theoretical studies using community assembly models could act as a basis for better empirical studies and monitoring programs, as well as provide a clearer understanding of the relationship among different types of impact. We then discuss some of the particular challenges that come from the need to prioritize invasive species in a management or policy context. We end with recommendations about how the field of invasion biology might proceed in order to build a general framework for understanding and predicting impacts. In particular, we advocate studies designed to explore the correlations among different measures: Are the results of complex multivariate methods adequately captured by simple composite metrics such as species richness? How well are impacts on native populations correlated with impacts on ecosystem functions? Are there useful bioindicators for invasion impacts? To what extent does the impact of an invasive species depend on the system in which it is measured? Three approaches would provide new insights in this line of inquiry: (1) studies that measure impacts at multiple scales and multiple levels of organization, (2) studies that synthesize currently available data on different response variables, and (3) models designed to guide empirical work and explore generalities. 相似文献