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1.
Socio-economic research on biotechnology is dealing mainly with the sectors of biopharmaceuticals, agro-food or environmental technologies. In contrast, the equipment and supplies sector seems to be largely ignored. This is surprising because this sector provides important input in terms of technology and material for the development of biotechnology in general. Our comparative analysis of the sector in eight countries indicates that there exists no specific science base for the sector and that it is largely neglected by public research funding. Commercial activities are concentrated in countries with a large general science base in biotechnology and strong multinational pharmaceutical or chemical companies. There is a rather broad diversity in the way the sector has developed in the eight countries. Our data support the notion that national peculiarities seem dominant for explaining this picture. We anticipate growing business opportunities for European firms to step into large markets of equipment and supplies for functional genomics and protein analyses where Europe maintains a strong science base.  相似文献   

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Maize plants were grown under four moisture regimes (wet to extreme deficit) and three constant temperatures (20°, 25° & 30°C) in a phytotron. Each plant was infested with one E-race European corn borer [Ostrinia nubilalis (Hubn.)] (ECB) egg mass at pollen shed. ECB development, location, and establishment were recorded over the course of 12 destructive sample dates (4/temperature). ECB developmental rates were not significantly affected by soil moisture treatments, but were significantly affected by temperature. In spite of successful establishment of four distinctly different soil moisture regimes, the maize stalk tissue water levels were not significantly different among soil water treatments. Instead, the maize plants exhibited accelerated leaf senescence in response to the water deficit conditions. Among the soil water treatments, differences were found in larval establishment, vertical distribution and dispersion, and feeding site selection; however, those effects were slight and could not explain the similarity in ECB developmental rates observed in these treatments.In maize, the larval environment within the stalk was effectively insulated from changes in the external environment by the plant's ability to maintain a relatively high and stable stalk tissue water content. Thus, large changes to the soil environment had essentially no effect on ECB development, though drastic consequences for the plant. This study indicates that ECB rates of development are relatively insensitive to changes in the soil water environment as well as the associated changes in the maize plant that accompany severe drought stress. The significance of these findings to insect modelling, crop physiology, and insect-crop interactions is discussed.
Résumé Des plants de maïs se développent dans un phytotron dans 4 conditions d'humidité du sol (de la saturation à la dessication) et à 3 températures constantes (20°, 25° & 30°C). Chaque pied est contaminé au moment de l'émission du pollen, par une ooplaque d'O. nubilalis Hübn. (ECB) de race européenne E. L'installation, la colonisation et le développement des chenilles sont notés lors de 12 périodes de prélèvements destructifs (4 par température). La vitesse de développement d'O. nubilalis est affectée par la température, main non par l'humidité du sol. Les 4 niveaux d'humidité du sol n'ont aucun effet sur la teneur en eau des tiges de maïs. En fait, les feuilles de maïs présentent une senescence précoce lorsqu'il y a déficit en eau dans le sol. La teneur en eau du sol agit sur l'installation, sur la distribution verticale, la dispersion et le lieu d'alimentation des chenilles; mais ces effets sont légers et ne modifient pas la vitesse de développement.L'environnement larvaire dans la tige de maïs est efficacement isolé des variations externes par l'aptitude de la plante à maintenir la teneur en eau des tiges relativement élevée et stable. Ainsi, des changements importants au niveau du sol n'ont pratiquement pas d'effets sur le développement d'O. nubilalis, malgré les conséquences brutales pour la plante. Cette étude montre que la vitesse de développement d'O. nubilalis est relativement insensible aux modifications de la teneur en eau du sol ainsi qu'aux effets de ce stress de sécheresse sévère sur le pied de maïs. La discussion porte sur l'importance de ces résultats pour la modélisation de la dynamique de l'insecte, la physiologie de la culture et les interactions entre insecte et plante.
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Three European representatives of the genus Fraxinus were studied for the first time for their rDNA and heterochromatin patterns. The physical mapping of two rRNA gene families 5S and 18S–5.8S–26S (45S) and the distributional pattern of GC-rich regions in the chromosomes have been established by means of fluorescence in situ hybridization (FISH) and fluorochrome banding with chromomycin A3. The genome size was assessed by flow cytometry. Heterochromatin and rDNA organization was conserved and almost identical for two species from Fraxinus section (F. angustifolia and F. excelsior). The number and position of rDNA loci in F. ornus (section Ornus) were similar; however, the organization of genes was quite different. In this species the 5S and 45S rRNA genes were colocalized at the level of satellites of two chromosome pairs bearing nucleolar organizing regions (NORs). One 5S locus was also observed under the 45S one of one chromosome pair. In F. angustifolia and F. excelsior, only 45S loci were situated at the level of satellites and secondary constrictions, while 5S was located just under 45S in the distal part of the short arm of one out of two marked pairs. The number and position of GC-rich DNA correspond to those of 45S loci. The genome size (2C value) was of 1.54 and 1.68 pg for F. angustifolia and F. excelsior, respectively. Fraxinus ornus possessed the highest 2C DNA value (1.98 pg). In the light of these cytogenetic features the clear differentiation between two sections (Fraxinus and Ornus) was observed both at the rDNA and genome size levels.  相似文献   

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Research collaboration between developed countries from the northern hemisphere and developing countries in the southern hemisphere is essential for the understanding and protection of the major proportion of biodiversity located in the tropics. Focusing on the case of sub-Saharan Africa, we here assess the real involvement of northern versus southern contributors, and caution against unequal academic benefit sharing arising from non-commercial biodiversity research that may ultimately hamper sustainable knowledge transfer and long-term biodiversity conservation. We discuss possible drivers that may have led to a business of raw biodiversity data. While we fully support the current efforts to stamp out biopiracy through international biodiversity policies and agreements, we illustrate that such legislative frameworks may further constrain biodiversity research, especially in countries where regulations are poorly streamlined and bureaucracy remains rather inert. We therefore ask for workable solutions towards more equal footing in north–south biodiversity research, and propose a number of steps to transgress the current barriers towards a more fair and equitable sharing of benefits arising from biodiversity research.  相似文献   

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In e-health intervention studies, there are concerns about the reliability of internet-based, self-reported (SR) data and about the potential for identity fraud. This study introduced and tested a novel procedure for assessing the validity of internet-based, SR identity and validated anthropometric and demographic data via measurements performed face-to-face in a validation study (VS). Participants (n = 140) from seven European countries, participating in the Food4Me intervention study which aimed to test the efficacy of personalised nutrition approaches delivered via the internet, were invited to take part in the VS. Participants visited a research centre in each country within 2 weeks of providing SR data via the internet. Participants received detailed instructions on how to perform each measurement. Individual’s identity was checked visually and by repeated collection and analysis of buccal cell DNA for 33 genetic variants. Validation of identity using genomic information showed perfect concordance between SR and VS. Similar results were found for demographic data (age and sex verification). We observed strong intra-class correlation coefficients between SR and VS for anthropometric data (height 0.990, weight 0.994 and BMI 0.983). However, internet-based SR weight was under-reported (Δ −0.70 kg [−3.6 to 2.1], p < 0.0001) and, therefore, BMI was lower for SR data (Δ −0.29 kg m−2 [−1.5 to 1.0], p < 0.0001). BMI classification was correct in 93 % of cases. We demonstrate the utility of genotype information for detection of possible identity fraud in e-health studies and confirm the reliability of internet-based, SR anthropometric and demographic data collected in the Food4Me study.Trial registration: NCT01530139 (http://clinicaltrials.gov/show/NCT01530139).

Electronic supplementary material

The online version of this article (doi:10.1007/s12263-015-0476-0) contains supplementary material, which is available to authorized users.  相似文献   

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BACKGROUND AND AIMS: Highly variable, yet possibly convergent, morphology and lack of sequence variation have severely hindered production of a robust phylogenetic framework for the genus Ophrys. The aim of this study is to produce this framework as a basis for more rigorous species delimitation and conservation recommendations. METHODS: Nuclear and plastid DNA sequencing and amplified fragment length polymorphism (AFLP) were performed on 85 accessions of Ophrys, spanning the full range of species aggregates currently recognized. Data were analysed using a combination of parsimony and Bayesian tree-building techniques and by principal co-ordinates analysis. KEY RESULTS: Complementary phylogenetic analyses and ordinations using nuclear, plastid and AFLP datasets identify ten genetically distinct groups (six robust) within the genus that may in turn be grouped into three sections (treated as subgenera by some authors). Additionally, genetic evidence is provided for a close relationship between the O. tenthredinifera, O. bombyliflora and O. speculum groups. The combination of these analytical techniques provides new insights into Ophrys systematics, notably recognition of the novel O. umbilicata group. CONCLUSIONS: Heterogeneous copies of the nuclear ITS region show that some putative Ophrys species arose through hybridization rather than divergent speciation. The supposedly highly specific pseudocopulatory pollination syndrome of Ophrys is demonstrably 'leaky', suggesting that the genus has been substantially over-divided at the species level.  相似文献   

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The European ground squirrel (Spermophilus citellus) is endangered and in decline. Populations are increasingly fragmented, and only a coordinated conservation effort at the European level may guarantee its long-term survival. To obtain a general population genetic picture on a larger geographic scale, we screened 117 individuals from seven local populations in Hungary, Romania, and Austria for allelic variation at eleven microsatellite loci. We found a high (23.4%) proportion of private alleles, and a moderate to somewhat elevated level (15.27%) of partitioning of genetic diversity among populations, compared to that found in many other terrestrial mammals. Genetic variability was significantly higher than in earlier studied Czech populations that are considered genetically depleted, but significantly lower than in undisturbed populations of S. suslicus and S. brunneus, that are similar to the European ground squirrel in their ecological requirements, reproductive biology, and social organization. Genetic diversity was also lower than in most presumably “undisturbed” populations of other Sciurid species. This, together with the observed level and pattern of genetic differentiation among populations, such as no significant increase of genetic differentiation with geographic distance and similar variance of genetic differentiation between populations independent of geographic distance, indicated the prevalence of relatively strong drift effects for all populations. A Bayesian STRUCTURE analysis and a factorial correspondence analysis concordantly revealed a fairly complex genetic composition of local populations, but no major geographic trend in the pattern of the genetic composition. Overall, the results suggest disintegration of local colonies that might earlier have been more connected genetically. The STRUCTURE analysis also suggested anthropogenic translocations among single Hungarian populations. Our data on genetic diversity and its distribution do not object to such conservation measures. Translocation of individuals particularly from nearby populations may increase the chances of survival of small and isolated populations and counteract inbreeding at low densities.  相似文献   

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Oocyte development was studied in a European strain of the bean weevil, Acanthoscelides obtectus. In the experimental system used, oocyte growth begins after several hours of imaginal life. The lengths of the terminal and penultimate oocytes were measured and correlations between these measurements showed that the latter stopped growing when the former was in the phase of accelerated growth.

Vitellogenin could be immunologically detected in the hemolymph of sexually mature females and was undetectable in males, larvae and in females immediately after imaginal exuviation. The moment of vitellogenin appearance in young females varies from one insect to another.

It appears that no specific external stimulus is required to initiate the synthesis and incorporation of the vitellin protein in this European strain.  相似文献   

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Karyotype and cytogenetic characteristics of European smelt Osmerus eperlanus were investigated using different staining techniques (sequential Ag-, CMA3 and DAPI banding) and PRINS to detect 5S rDNA and telomeric sites. The diploid chromosome number was invariably 2n = 56 and karyotype composed of 5 pairs of metacentrics, 9 pairs of subtelocentrics and 14 pairs of subtelo- to acrocentrics. The DAPI-positive heterochromatic regions were found in centromeric positions on bi-armed chromosomes and few acrocentrics. Additionally, some interstitial DAPI-positive bands were identified on three pairs of submetacentric chromosomes. The nucleolar organizer regions (NORs) were detected in the short (p) arms of the largest metacentric pair of chromosomes No. 1. Sequential banding (Giemsa-, AgNO3 and CMA3 stainings) revealed NOR sites corresponding to achromatic regions but not associated with CMA3-positive blocks of heterochromatin located on either side of NORs. Individuals from the analyzed population had this conspicuous pair of chromosomes always in heterozygous combination. A complex inversion system was hypothesized to be involved in the origin of the observed variation but analysis with telomeric PRINS and PNA-FISH did not reveal any Interstitial Telomeric Sites (ITS). Hybridization signals were confined exclusively to terminal chromosomal regions. The 5S ribosomal sites as revealed by PRINS were found to be invariably located in the short (p) arms of four pairs of subtelocentric chromosomes. Cytotaxonomic comparisons of the present results with the voluminous available cytogenetic data-set from salmoniform and esociformes fishes appear to support the recent view, based on robust molecular-based phylogeny, that salmoniform and osmeriform fishes are not as closely related as previously assumed.  相似文献   

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Population structure, in terms of the body mass, condition, sex and reproductive status of individuals, has been found to vary in phase with population density in cyclic populations of microtine rodents. Because sustained population cycles involve delayed density dependent changes in the population growth rate, we would expect at least some life history traits also to depend on past densities. Detailed, long-term studies of changes in vole life history traits are however few, and are largely restricted to northern Europe. In view of the uncertainty as to whether the cyclic microtine populations of western Europe represent the same phenomenon as those of northern Europe, we studied temporal variation in the structure of a clearly cyclic population of the common vole Microtus arvalis Pallas, in the cereal plains of mid-western France. Our data set contains seasonal, individual-level data from long-term, large-scale trapping covering four entire population cycles. We found considerable cyclic variation in population structure in spring (April), but less so in summer (June). In spring of post-peak years, animals were of low body weight and body condition (particularly females), litter sizes were smaller and there was a reduction in the proportion of breeders. All of these could be proximal drivers of increased mortality rates, or decreased birth rates, contributing to the population declines. Few life history traits, however, showed direct density dependent variation, and none of the traits studied here showed delayed density dependence. We have shown declines in the fecundity and body condition of voles from a western European population that coincides with, and may be a proximal cause of, cyclic declines in population density. Closer attention to proximal causes, by which ecological processes drive cycles, could clarify the extent to which microtine cycles across Europe represent a single phenomenon.  相似文献   

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We analyzed individual variation in work load (nest visit rate) during chick‐rearing, and the consequences of this variation in terms of breeding productivity, in a highly synchronous breeder, the European starling (Sturnus vulgaris) focusing on female birds. There was marked (10‐ to 16‐fold) variation in total, female and male nest visit rates, among individuals, but individual variation in female nest visit rate was independent of environment (rainfall, temperature) and metrics of individual quality (laying date, clutch size, amount of male provisioning help), and was only weakly associated with chick demand (i.e., day 6 brood size). Female nest visit rate was independent of date and experimentally delayed birds provisioned at the same rate as peak‐nesting birds; supporting a lack of effect of date per se. Brood size at fledging was positively but weakly related to total nest visit rate (male + female), with >fivefold variation in nest visit rate for any given brood size, and in females brood size at fledging and chick mass at fledging were independent of female nest visit rate, that is, individual variation in workload was not associated with higher productivity. Nevertheless, nest visit rate in females was repeatable among consecutive days (6–8 posthatching), and between peak (first) and second broods, but not among years. Our data suggest that individual females behave as if committed to a certain level of parental care at the outset of their annual breeding attempt, but this varies among years, that is, behavior is not fixed throughout an individual's life but represents an annually variable decision. We suggest females are making predictable decisions about their workload during provisioning that maximizes their overall fitness based on an integration of information on their current environment (although these cues currently remain unidentified).  相似文献   

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Two of the classical kallikrein genes KLK3 and KLK2 on 19q13.4 are plausible candidates in prostate cancer susceptibility. They are expressed almost exclusively in prostate tissue. We have performed a comprehensive analysis of association of variants in these two genes with prostate cancer among men of European descent using a tagging SNP approach. Thirteen SNPs selected from the HapMap database were analyzed in a sample of 596 histologically verified prostate cancer cases and 567 ethnically matched controls. Five SNPs showed significant association at single marker level. Linkage disequilibrium (LD) analysis revealed four LD blocks. We performed a haplotype analysis within each LD block. A major haplotype in block 1 that contains the first two significantly associated SNPs was significantly underrepresented in the prostate cancer cases; a second haplotype in block 3 also showed significant frequency differences between cases and controls. Four of the studied SNPs show positive associations with serum PSA levels. A structure analysis revealed no population stratification in our samples that could have confounded the association results. These findings suggest a plausible role of kallikrein gene variants in the etiology of prostate cancer among men of European ancestry.  相似文献   

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Exploring late-generation ethnicity automatically raises a long-ignored question: whether it will end and how: through what terminal stages and processes? In America, this question currently makes sense only for late-generation descendants of the European immigration wave that lasted roughly from the 1870s to 1924. However, answering it prepares the ground for eventually asking it also about late-generation ethnics in newer waves of immigration.  相似文献   

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Intraspecific diversity and molecular relations among regional populations were studied for 16 moss species in three European regions, Central Europe, Southern Scandinavia, and Northern Scandinavia, based on internal transcribed spacer and rpl16 G2 intron. The range of nuclear diversity values found is mainly similar to that of other organisms, and to that found in bryophytes from other regions, but higher diversity was found in Isothecium alopecuroides (Dubois) Isov. No correlations were found between diversity values or number of haplotypes unique to a region and morphological diversity, geographical distribution range, or regional frequency, possibly since this study did not include sufficiently rare species to reflect the factors affecting such species. Finally, no general differences in diversity levels were found among the three studied regions. When haplotype composition is considered, differences were found among the regions for some species, but again no general inter-regional pattern of intraspecific relationships exists. While it is clear that intraspecific variation is crucial to consider in biodiversity conservation contexts since a high proportion of the total diversity is found below the species level, it is also evident that it is necessary to investigate each individual species rather than to rely on what has been found for other taxa.  相似文献   

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