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Over the last 15 years, despite the lack of a specific strategy or a dedicated financial instrument to deal with invasive alien species (IAS), the European Commission (EC) has contributed to financing almost 300 projects addressing this issue, for a total budget exceeding 132 million EUR. Such figures are based on projects funded under two specific EU financial tools: LIFE and the RTD Framework Programmes. The contribution of the two programmes has been characterised by an overall positive trend over the years, in terms of both the number of projects and the budget spent. Such trend can be assumed to reflect an overall increase in both the awareness of the problem among wildlife managers and scientific institutions, and the willingness to pay by the EC institutions and the EU citizens in general. Such data might contribute to the development of a response indicator measuring ‘Trends in invasive alien species in Europe’, useful to assess progress toward the target of halting the loss of biodiversity by 2010—as a part of the SEBI 2010 process. The results may also contribute to assess the economic impact of IAS in Europe—in terms of costs for reduction and/or prevention of damages—and to support policy decisions and communication campaigns. Finally, the results are encouraging and support the need for the development and the implementation of a sound EU strategy on IAS, so as to regulate and optimise the administration of the available financial resources—whenever appropriate—on the basis of specific priorities.  相似文献   

3.
The Author agrees in principle with the question/statement, but states also that an important qualification is needed within this question. In fact, it is not possible by the bottom up approach to find the conditions for the synthesis of our actual proteins—lysozyme, chymotrypsin or the like—however it is possible to show experimentally that co-oligopeptides chains of that length can be produced by prebiotic reactions. Considering such a synthesis, it is important to recall that proteins—and nucleic acids—are not simply polymers, but are co-polymers, and the kinetics and thermodynamics attending the synthesis of copolymers poses stringent constraints for the biogenesis and growth of specific sequences. Such constraints are examined and discussed. Presented at: International School of Complexity–4th Course: Basic Questions on the Origins of Life; “Ettore Majorana” Foundation and Centre for Scientific Culture, Erice, Italy, 1–6 October 2006.  相似文献   

4.
Five small water bodies located within the agricultural region of Wielkopolska (west Poland) underwent investigation. Periphyton samples were collected from various macrophyte habitats representing rush vegetation (in five water bodies), submerged aquatic plants (in three) and nymphaeids (in one): Palędzie — Ceratophyllum demersum, Potamogeton crispus, Typha latifolia; Batorowo — Phragmites australis; Piotrowo — Potamogeton natans, Ceratophyllum submersum, Typha latifolia; Tarnowo Podgórne — Typha latifolia; Dąbrówka — Zannichellia palustris, Potamogeton pectinatus, Phragmites australis. The main goal of the study was to determine the composition and abundance of the periphytic communities inhabiting various types of rush and water vegetation of five water bodies located within a mid-field landscape area. Diatoms such as Achnanthidium minutissimum, Amphora ovalis, Cocconeis placentula orNavicula cincta revealed significantly higher densities in the zone of elodeids, while green algae prevailed among nymphaeids. As a result of this study it was found that the epiphytic algae were characterised by much lower diversity in respect to a specific water body, though much greater diversity was observed in its relation to the type of substratum. Two types of habitats were distinguished — the first of simple build (helophytes and nympheids) and the second containing the complicated architecture of plant stems (elodeids).  相似文献   

5.
Excepting some specific efforts, most of the mainstream debate around the Americas’ settlement has been directed by specialists dealing with partial evidence. Thus, discussions have been confined to particular academic and scientific environments with limited interchange among archeologists, physical anthropologists, linguists, geneticists, geologists, paleontologists, and so on. As a consequence, integrative views about a process that is complex by definition have been scarce and driven by confrontation rather than by a search for common results. Still, an increasing number of specialists are attempting to integrate different types of data. In our view, a proper way to do this is to focus the discussion around evolutionary or cultural processes and the putative patterns that such processes could have generated in the different types of data, which in turn, depend on the nature of the data. In this way, the analyses and conclusions can be interpreted as “model-bound” rather than purely inferential. In this paper, we first provide a brief summary of main differences among the two main sources of biological information—genetics and craniofacial size and shape—along with the main conclusions that the patterns of genetic and craniofacial variation provide. Furthermore, we exemplify the above-mentioned notion by discussing two particular processes and their hypothetical impact on genetic and craniofacial data: the influence of bottlenecks during the early dispersal and a putative zone of gene flow among Asian and American Circum-Arctic populations.  相似文献   

6.
Summary We localized the chromosomal targets of several of the regulatory controls of expression of theCAR1 gene. Fusion tolacZ of several fragments of the 5′ non-coding region showed that induction ofCAR1 by arginine is positively regulated by the products of theARGR genes. The target lies upstream of another site where repression by the CARGRI molecule occurs. The latter control is not specific to arginine catabolism since it also affectsCYC-1 and indeed does not appear to involve arginine. The primary target of the two other regulatory allelesCARGRII andCARGRIII is not situated in the 5′ non-coding region. Deletion analysis supports the fusion data and confirms the order of the regulatory regions: 5′—nitrogen catabolite repression—activation by arginine—CARGRI-mediated repression—CAR1.  相似文献   

7.
Using HeLa S-3 cells synchronized by selective detachment, in this paper we report a parallel study of nuclear morphology and autoradiography grain patterns between middle G1 and middle S phases: Our results show two distinct [3H]-thymidine labeling patterns. The first “peripheral” labeling pattern has a characteristic nuclear size distribution, in contrast to the heterogeneous and varying size distributions of Feulgen-stained nuclei, and apparently is characteristic of very early S phase. The sizes of the second labeling pattern—homogeneous or inhomogeneous grain distribution throughout the nucleus—are equal or larger than the first and vary with S phase progression. Together, the corresponding nuclear sizes of the labeled nuclei represent the larger extreme of nuclear areas, and the labeling index closely parallels the fraction of nuclei with areas larger than the minimum size of the labeled nuclei. These results suggest a characteristic nuclear size (reflecting unique intranuclear DNA distribution) as a necessary, if not sufficient, requirement for S phase initiation. Parallel experimentation with rat liver cells—synchronized in vivo by partial hepatectomy and analyzed by thin section autoradiography—confirms the existence of a peripheral labeling pattern in both the very early part and the very late part of S phase, which reconciles our data with previous results and points to the fact that both initiation and termination sites for DNA replication are near the nuclear periphery.  相似文献   

8.
In the present work the responses of β-glucosidase in leaves of tomato plants subjected to various stress factors of both pathogenic (fungi, bacteria, viruses) and abiotic origin (heat shock) were studied. Biochemical and cytochemical methods were applied. It was established that an increase of β-glucosidase activity is induced uniquely by fungal pathogens. The cytochemical tests confirm the finding. Hence, the conclusion can be drawn that β-glucosidase response is a specific character of fungal pathogenesis in tomato; probably, the enzyme is involved in plant — fungi recognition. The data are in accordance with our previous results on tobacco and wheat — stress stimuli systems.  相似文献   

9.
Cell respiratory activity of protoplasts obtained from the wild type of Neurospora crassa and photoreceptor complex WCC—white collar 1 (wc-1) and white collar 2 (wc-2)—mutants of Neurospora crassa strains was investigated. Respiration inhibition by KCN in the presence of 25 mM succinate was similar in all strains and did not exceed 83–85% against control. The significant induction of KCN-resistant respiratory pathway occurred under 1% glucose oxidation in wc-1 and wc-2 mutants if compared with the wild type strains. The inhibitors of the main (cytochrome) pathway of electron transfer in mitochondria—1 mM KCN and antimycin A (4 μg/ml)—blocked the respiration rate of the protoplasts from N. crassa wild type by 75%, while the cell respiration of wc-1 and wc-2 strains was suppressed by approximately 50%. The specific inhibitor of alternative oxidase—10 mM salicylhydroxamic acid (SHAM)—in combination with the blockers of mitochondrial electron transfer chain caused the total suppression of respiratory activity of protoplasts in all studied strains. It is supposed that an increase of KCN-resistance in WCC mutants under glucose oxidation is connected with alternative oxidase activation as the result of failure in reception and signal transduction of active oxygen species.  相似文献   

10.
In systematics, the importance of a species’ name is obvious and very considerable — it may even affect the names of other taxa (genera and families). Here, I argue that in some specific circumstances the name of a species may also indirectly play some role in the public understanding of the theory of evolution and creationism — or at least, has the potential to play such a role.  相似文献   

11.
Vilkov  E. V. 《Biology Bulletin》2019,46(10):1269-1281
Biology Bulletin - Abstract—The results of our bird counts carried out in 1996–2017 in inner mountain and high-mountain Dagestan are analyzed. The bird specific composition, average...  相似文献   

12.
This paper deals with information transfer from the environment and “self”-organization in open, nonlinear systems far from thermodynamic equilibrium — in the presence of either non-stationary phase jitter noise, or amplitude stationary noise. By “self”-organization we mean here the progressive formation within the system of sequential, ordered (coherent) relationships between appropriate dynamical variables-like for example, the phase differences between the oscillating components of the system. We take up (in Section II) the classical Laser as a specific example and examine in detail the influence of phase jitter noise in the mode (phase) locking process. We find—as expected—that phase fluctuations in the cavity cause degradation of the coherent behaviour (i.e. increase the entropy) of the system — which, however, levels off, or saturates with time. Further (in Section III) we examine systems where the number of self-sustained oscillating components may vary with time in such a way that the maximum entropy of the system increases faster than the overall instantaneous entropy. We put forth the hypothesis that in such cases — because of the increase of the redundancy — the system gets organized not just in spite of, but merely because of the presence of Noise. Possible applications in biological systems (especially concerning a model of cerebral organization) are briefly discussed. It is understood here, that the system has to display some preliminary dynamical structure before the organizing procedure takes over. What happens afterwards is the subject of this paper.  相似文献   

13.
A 1.6 kb upstream regulatory sequence (GenBank accession no. AF472487) of plasma membrane aquaporinBnPIP1 gene fromBrassica napus was obtained by genomic walking based on ligation-mediated PCR method. Sequence analysis indicated that this fragment contained seed germination specific and vascular specific sequences. The 1.6 kb upstream sequence and various 5′ end deleted sequences were fused withuidA gene and constructed into plant expression vectors which were used for tobacco transformation. GUS histochemical assay showed that the 1.6 kb fragment had high levels of promoter activity and the GUS staining was mainly distributed in vascular systems and tissues with rapid expanding and proliferating cells. Promoter deletion analysis showed that the deletion of -1610 — -1030 bp resulted in a dramatic reduction in GUS activity. It was assumed that there might be cis-acting element(s) existing in this region. Whereas, the region located at -1030 — -902 bp strongly inhibited the expression ofgus and probably contained negative regulatory element(s). The fragment of -902 — -19 bp could also directgus expression at high level.  相似文献   

14.
Chorological structure of ichthyofauna of the Arctic Region is described. Distribution patterns of 504 fish-like vertebrates and fish species are characterized. One hundred and eighty-nine range types are defined, which are combined into eight main categories: 1—Arctic; 2—Atlantic-Arctic; 3—transitional subarctic zone of Atlantic sector; 4—Pacific-Arctic; 5—transitional subarctic subarctic zone of Pacific sector, 6—Pacific-Atlantic (amphiboreal); 7—bipolar; 8—continental (fresh and brackish waters). Arctic and boreal regions are bordered by transitional (subarctic) zones, which are the areas of intermutual penetration of faunas. The distribution of most fish species that penetrate into to the Arctic Region from the southern areas is limited by these transitional zones. The benthic fish species prevail in the group of autochthonous Arctic species (which includes 64 species or 14% of marine fauna). The demersal fauna of the Arctic preudoabyssal is presented by endemic species. Ten variations of amphiboreal distribution patterns are revealed. Three areas may be defined within the Atlantic-subarctic zone in regard to the fish fauna and range types, i.e., Labrador-Greenland region, the Barents Sea region, and Icelandic (transitional) region.  相似文献   

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The structure of root-associated bacterial populations in the legume common bean (Phaseolus vulgaris L.), was studied in plants grown under nitrogen sufficiency and under conditions inducing nitrogen deficiency. Similar cell numbers were obtained in the rhizosphere of nitrogen-amended plants as compared to nitrogen-deficient plants and between various root parts—tip, elongation and branching zones—using DAPI staining. In contrast, a higher proportion of DAPI-stained cells from the nitrogen-amended plants hybridized with a fluorescence-labeled EUB338 probe for theBacteria domain than cells originating from nitrogen-deficient plants. Shifts in the percentages of EUB338-reactive cells—as well as in absolute cell number—hybridizing to fluorescent rRNA-directed probes specific for the α and γProteobacteria and for high GC content gram-positive bacteria in separated root segments were detected between the treatments. No such differences were found using β and δProteobacteria or rRNA group I pseudomonad targeted probes. Denaturating gradient gel electrophoresis profiles of PCR products obtained from the same samples and amplified withBacteria-domain targeted primers supported the results obtained with the whole cell hybridizations. The advantages and drawbacks of the techniques applied are discussed.  相似文献   

17.
The dominant modalities of treatment for alcoholism in Russia are suggestion-based methods developed by narcology—the subspecialty of Russian psychiatry which deals with addiction. A particularly popular method is the use of disulfiram—an alcohol antagonist—for which narcologists commonly substitute neutral substances. Drawing on 14 months of fieldwork at narcological clinics in St. Petersburg, this article examines the epistemological and institutional conditions which facilitate this practice of “placebo therapy.” I argue that narcologists’ embrace of such treatments has been shaped by a clinical style of reasoning specific to a Soviet and post-Soviet psychiatry, itself the product of contested Soviet politics over the knowledge of the mind and brain. This style of reasoning has facilitated narcologists’ understanding of disulfiram as a behavioral, rather than a pharmacological, treatment and has disposed them to amplify patients’ responses through attention to the performative aspects of the clinical encounter and through management of the treatment’s broader reputation as an effective therapy. Moreover, such therapies have generally depended upon, and helped to reinforce, clinical encounters premised on a steeply hierarchical physician–patient relationship.  相似文献   

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The objective of this paper is to propose and assess an estimation procedure—based on data assimilation principles—well suited to obtain some regional values of key biophysical parameters in a beating heart model, using actual Cine-MR images. The motivation is twofold: (1) to provide an automatic tool for personalizing the characteristics of a cardiac model in order to achieve predictivity in patient-specific modeling and (2) to obtain some useful information for diagnosis purposes in the estimated quantities themselves. In order to assess the global methodology, we specifically devised an animal experiment in which a controlled infarct was produced and data acquired before and after infarction, with an estimation of regional tissue contractility—a key parameter directly affected by the pathology—performed for every measured stage. After performing a preliminary assessment of our proposed methodology using synthetic data, we then demonstrate a full-scale application by first estimating contractility values associated with 6 regions based on the AHA subdivision, before running a more detailed estimation using the actual AHA segments. The estimation results are assessed by comparison with the medical knowledge of the specific infarct, and with late enhancement MR images. We discuss their accuracy at the various subdivision levels, in the light of the inherent modeling limitations and of the intrinsic information contents featured in the data.  相似文献   

20.
Juri Lotman distinguishes between two main types of communication. In addition to the classical I-YOU communication, he speaks about I-I communication, where both the addresser and the addressee are one and the same person. Contrary to how it sounds, autocommunication is not self-sufficient musing inside one’s self, it is remodelling oneself through a code from an entity outside oneself, be it animate or inanimate. According to Lotman, it is often the rhythmical phenomena like poetry, the rhythm of waves, etc. that lend themselves for the act of autocommunication as external codes. After having received the message one is not identical to the original oneself anymore. Perceptual markers of landscape—specific rhythms, ephemera, the rhythm of human everyday activities, bodily movement—can be considered as a secondary code leading to autocommunication in the person who contemplates the landscape. Looking at the landscape—which also implies the rhythmical movement of the eyes—one uses it as a code to reconstitute oneself. A person who has confronted a landscape does not leave it as the same person. The present article poses a definition of autocommunication in landscapes and discusses the way in which other sensorial information apart from the visual—smell, movement, rhythms etc—are used culturally to reinforce autocommunication with oneself. It can be said that several institutionalised religious and cultural practices expect the subject to reconstitute him- or herself mainly through the bodily landscape experience.  相似文献   

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