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Riccardo Scalera 《Biological invasions》2010,12(1):173-177
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.
Pier Luigi Luisi 《Origins of life and evolution of the biosphere》2007,37(4-5):363-365
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.
The epiphytic communities of various ecological types of aquatic vegetation of five pastoral ponds 总被引:1,自引:0,他引:1
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.
Raymond Cunin Evelyne Dubois Gerrit Vanthienen Kristof Tinel Annemie Jacobs Marjolaine Crabeel 《Molecular & general genetics : MGG》1986,205(1):170-175
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.
Claudio Nicolini Andrew S. Belmont Antonietta Martelli 《Cell biochemistry and biophysics》1986,8(2):103-117
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.
Aglika Edreva Violeta Sotirova Iordanka D. Georgieva Elisaveta Stoimenova Rositza Rodeva Nevena Bogatzevska 《Acta Physiologiae Plantarum》2000,22(3):274-277
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.
E. P. Isakova Yu. I. Deryabina N. N. Gessler T. A. Belozerskaya Ya. M. Rabinovich 《Applied Biochemistry and Microbiology》2010,46(3):318-323
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.
Tomasz Skawiński 《Evolution》2012,5(1):163-164
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.
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
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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.
N. V. Chernova 《Journal of Ichthyology》2011,51(10):825-924
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.
Eugene Raikhel 《Culture, medicine and psychiatry》2010,34(1):132-168
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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Chabiniok R Moireau P Lesault PF Rahmouni A Deux JF Chapelle D 《Biomechanics and modeling in mechanobiology》2012,11(5):609-630
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.
Kati Lindström 《Biosemiotics》2010,3(3):359-373
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