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Ljubinka Francuski Marko Djurakic Jasmina Ludoški Vesna Milankov 《Journal of Zoological Systematics and Evolutionary Research》2013,51(3):227-238
A study of population connectivity of the migratory insect species, such as dronefly Eristalis tenax (Diptera, Syrphidae), has an essential importance in understanding the relative influence of the evolutionary forces and environmental features that interact in the spatial distribution of molecular and morphological diversity. However, specific study aiming to understand spatial genetic structure of dronefly populations and its migratory potential is lacking. Hence, we studied a spatial pattern of genetic and phenotypic variation of seven European populations of E. tenax incorporating landscape genetic methods using allozyme data, wing size and shape and abdominal colour pattern. Based on the observed lack of genotypic structuring, we suggested that there has been sufficient long‐distance gene flow to effectively homogenize population structuring at a broader geographical scale. Wing shape similarity among populations and an overlap of abdominal colour variation showed no clear clustering related to geography, which is in congruence with genetic data. However, genetic (FST values) and phenotypic (wing size) data and landscape genetics indicated subdivision between the Balkan populations (four Serbian samples) and populations from Central (Germany and Switzerland) and Northern (Finland) Europe. These findings indicated a potential connection between the Central and Northern Europe supporting the Central European origin of the flies caught in Finland. Thus, by performing spatial analysis and combining genetic–morphological approach, we shed light on the movement pattern in complex landscapes and thus provided the necessary guidelines to a broad‐scale analysis of this widespread generalist pollinator. 相似文献
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Nees Jan van Eck Ludo Waltman Anthony F. J. van Raan Robert J. M. Klautz Wilco C. Peul 《PloS one》2013,8(4)
Background
Citation analysis has become an important tool for research performance assessment in the medical sciences. However, different areas of medical research may have considerably different citation practices, even within the same medical field. Because of this, it is unclear to what extent citation-based bibliometric indicators allow for valid comparisons between research units active in different areas of medical research.Methodology
A visualization methodology is introduced that reveals differences in citation practices between medical research areas. The methodology extracts terms from the titles and abstracts of a large collection of publications and uses these terms to visualize the structure of a medical field and to indicate how research areas within this field differ from each other in their average citation impact.Results
Visualizations are provided for 32 medical fields, defined based on journal subject categories in the Web of Science database. The analysis focuses on three fields: Cardiac & cardiovascular systems, Clinical neurology, and Surgery. In each of these fields, there turn out to be large differences in citation practices between research areas. Low-impact research areas tend to focus on clinical intervention research, while high-impact research areas are often more oriented on basic and diagnostic research.Conclusions
Popular bibliometric indicators, such as the h-index and the impact factor, do not correct for differences in citation practices between medical fields. These indicators therefore cannot be used to make accurate between-field comparisons. More sophisticated bibliometric indicators do correct for field differences but still fail to take into account within-field heterogeneity in citation practices. As a consequence, the citation impact of clinical intervention research may be substantially underestimated in comparison with basic and diagnostic research. 相似文献5.
Journal of Insect Conservation - The first step in monitoring and management of any taxa includes resolving taxonomic ambiguities which complicate the identification of its management units. One of... 相似文献
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A multispecies-based taxonomic microarray targeting coding sequences of diverged orthologous genes in Saccharomyces cerevisiae, Saccharomyces paradoxus, Saccharomyces mikatae, Saccharomyces bayanus, Saccharomyces kudriavzevii, Naumovia castellii, Lachancea kluyveri and Candida glabrata was designed to allow identification of isolates of these species and their interspecies hybrids. Analysis of isolates of several Saccharomyces species and interspecies hybrids demonstrated the ability of the microarray to differentiate these yeasts on the basis of their specific hybridization patterns. Subsequent analysis of 183 supposed S. cerevisiae isolates of various ecological and geographical backgrounds revealed one misclassified S. bayanus or Saccharomyces uvarum isolate and four aneuploid interspecies hybrids, one between S. cerevisiae and S. bayanus and three between S. cerevisiae and S. kudriavzevii . Furthermore, this microarray design allowed the detection of multiple introgressed S. paradoxus DNA fragments in the genomes of three different S. cerevisiae isolates. These results show the power of multispecies-based microarrays as taxonomic tools for the identification of species and interspecies hybrids, and their ability to provide a more detailed characterization of interspecies hybrids and recombinants. 相似文献
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Bernard Van Eerdenbrugh Bernard Stuyven Ludo Froyen Jan Van Humbeeck Johan A. Martens Patrick Augustijns Guy Van den Mooter 《AAPS PharmSciTech》2009,10(1):44-53
In this study, scaling down nanosuspension production to 10 mg of drug compound and evaluation of the nanosuspensions to 1 mg
of drug compound per test were investigated. Media milling of seven model drug compounds (cinnarizine–indomethacin–itraconazole–loviride–mebendazole–naproxen–phenytoin)
was evaluated in a 96-well plate setup (10, 20, and 30 mg) and a glass-vial-based system in a planetary mill (10, 100, and
1,000 mg). Physicochemical properties evaluated on 1 mg of drug compound were drug content (high-performance liquid chromatography),
size [dynamic light scattering (DLS)], morphology (scanning electron microscopy), thermal characteristics (differential scanning
calorimetry), and X-ray powder diffraction (XRPD). Scaling down nanosuspension production to 10 mg of drug compound was feasible
for the seven model compounds using both designs, the planetary mill design being more robust. Similar results were obtained
for both designs upon milling 10 mg of drug compound. Drug content determination was precise and accurate. DLS was the method
of choice for size measurements. Morphology evaluation and thermal analysis were feasible, although sample preparation had
a big influence on the results. XRPD in capillary mode was successfully performed, both in the suspended state and after freeze-drying
in the capillary. Results obtained for the latter were superior. Both the production and the physicochemical evaluation of
nanosuspensions can be successfully downscaled, enabling nanosuspension screening applications in preclinical development
settings. 相似文献
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