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1.
The EU Biodiversity Strategy stipulates in Target 2, Action 5 that the member states must map and assess the state of the ecosystems and their services and promote the integration into the reporting systems at the EU and national level by 2020. Therefore indicators for capturing and assessing ecosystem services (ES) are needed. In this paper we report for which ES class types currently ES indicators are being developed for Germany in the context of an ongoing research project. Additionally, we provide the indicator specifications, which are based on underlying framework concept. By way of the example of the provisioning service ‘raw wood production’ and the development of the main-indicator ‘annual wood accrual’ and six sub-indicators, we illustrate the concrete procedure, including discussion of results and target values. The indicators for the ES wood provision are not only suitable for an exemplary illustration of procedure, data selection and data basis in Germany. Furthermore, it shows that indicators for provisioning ES can eminently conflict with biodiversity and other ES. 相似文献
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The homology concept has had a long and varied history, starting out as a geometrical term in ancient Greece. Here we describe
briefly how a typological use of homology to designate organs and body parts in the same position anatomically in different
organisms was changed by Darwin’s theory of evolution into a phylogenetic concept. We try to indicate the diversity of opinions
on how to define and test for homology that has prevailed historically, before the important books by Hennig (1950. Grundzüge
einer Theorie der Phylogenetischen Systematik. Deutscher Zentralverlag, Berlin) and Remane (1952. Die Grundlagen des Natürlichen
Systems, der Vergleichenden Anatomie und der Phylogenetik. Geest & Portig, Leipzig) brought more rigor into both the debate
on homology and into the usage of the term homology among systematists. Homology as a theme has recurred repeatedly throughout
the history of the “Phylogenetisches Symposium” and we give a very brief overview of the different aspects of homology that
have been discussed at specific symposia over the last 48 years. We also honour the fact that the 2004 symposium was held
in Jena by pointing to the roles played by biologists active in Jena, such as Ernst Haeckel and Carl Gegenbaur, in starting
the development towards a homology concept concordant with an evolutionary world view. As historians of biology, we emphasize
the importance of major treatises on homology and its history that may be little read by systematists active today, and have
sometimes also received less attention by historians of biology than they deserve. Prominent among these are the works of
Dietrich Starck, who also happened to be both a student, and later a benefactor, of systematics at Jena University. 相似文献
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Thomas J. Manning Thomas Leggett Dustin Jenkins Ivan Furtado Dennis Phillips Greg Wylie Benjamin J. Bythell Fengli Zhang 《Bioorganic & medicinal chemistry letters》2013,23(15):4453-4458
In the first phase of this study, the binding of hydroxychloroquine to the copper(II) cation is examined using liquid chromatography–mass spectrometry (LC–MS), matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS), Fourier transform-ion cyclotron resonance spectrometry (FT-ICR) and nuclear magnetic resonance (1H and 13C NMR) in one and two dimensions. The data suggest the metal–ligand complex is a polarity adaptive molecule. In the second phase of the study, the complexes activity is tested against the National Cancer Institute’s 60 cell line panel. Its anti-cancer activity is compared to quinine, Cu(II)–quinine and hydroxychloroquine. It serves as a base line for future anti-cancer complexes in which hydroxychloroquine is utilized for its ability to impact cell autophagy. 相似文献
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Adolf Heschl 《Acta biotheoretica》1992,40(1):23-30
This paper discusses the widespread use of heritability calculations in recent behaviour research including behaviour genetics. In the sequel, a radical criticism concerning the basic axioms of the underlying, more general concept itself is presented. The starting point for testing the proclaimed universal validity of this concept stems from a fictitious yet realistic example taken from learning research. The theoretical result, based on the application of the conventional reasoning in this field, states that developmental processes — and learning is only one specific case out of an immense number of similar behavioural mechanisms — can neither be adequately described nor causally explained with sufficient reliability within the context of the heredity paradigm. On the contrary, an inherent inconsistency of the concept itself when applied to behaviour processes is demonstrated. Finally, a conceptual alternative involving a systems-theoretical approach to the problem is presented: In such a perspective it is the concept of cognition which represents the adequate explanatory theorem - a theorem in which quantitative processing of information from the environment is clearly revealed to belong to a subordinate level of living organization. 相似文献
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Guimarães ET Domingos M Alves ES Caldini N Lobo DJ Lichtenfels AJ Saldiva PH 《Environmental and Experimental Botany》2000,44(1):1-8
Tradescantia pallida cv. purpurea, a popular garden plant in Brazil, was used for the Tradescantia micronucleus (Trad-MCN) assay. In situ monitoring of the genotoxicity of air pollutants was carried out by sentinel approach, using the plant grown in the field or using the plants in pots which were carried to the monitoring sites. Two highly polluted sites, in S?o Paulo city (Cerqueira Cesar and Congonhas) and two rural sites (the cities of Pirassununga, 200 km and Caucaia do Alto, 50 km from S?o Paulo, respectively) were chosen for this study, in order to determine the gradient difference of the air pollution levels. Sentinel plants in Congonhas site presented the highest frequency of micronuclei (4.4%), in comparison with 2.2 and 2.3% found in plants from Pirassununga and Cerqueira Cesar sites, respectively (Kruskal-Wallis; P<0.020). Significant increases (F test; P<0.0001) in the frequency of micronuclei were observed in plants exposed in the polluted urban sites (Cerqueira Cesar: 5.7%; Congonhas: 7.1% and Caucaia do Alto: 2.3%). The increase in the frequency of micronuclei observed indicates the potential risk of mutagenicity in presence of high concentrations of pollutants. 相似文献
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Summary The peripheral root cap and protoderm inArabidopsis thaliana are organized into modular packets of cells derived from formative T-divisions of the root cap/protoderm (RCP) initials and subsequent proliferative divisions of their daughter cells. Each module consists of protoderm and peripheral root cap packets derived from the same periclinal T-division event of an RCP initial. Anatomical analyses are used to interpret the history of extensively coordinated cell divisions producing this modular construction. Within a given layer of root cap, the columella and RCP initials divided in a centrifugal sequence from the innermost columella initials toward the RCP initials. All RCP initials in the lineages around the circumference of the root divided nearly simultaneously in waves to form one module prior to the next wave of initial divisions forming a younger module. The peripheral root cap and protoderm packets within each module completed four rounds of proliferative divisions in the axial plane to produce, on average, 16 cells per packet in the basalmost modules in axial view. Peripheral root cap and protoderm cells predominantly in the T-type (trichoblast) lineages also underwent radial divisions as they were displaced basipetally. The regularity in the cellular pattern within the modules suggests a timing mechanism controlling highly coordinated cell division in the initials and their daughter cells.Abbreviations RAM
root apical meristem
- RCP
root cap protoderm
- prc
peripheral root cap 相似文献
8.
Anna Kajaste-Rudnitski Cinzia Pultrone Flavia Marzetta Silvia Ghezzi Tiziana Coradin Elisa Vicenzi 《Amino acids》2010,39(1):1-9
Viral tropism, replication, and pathogenesis are determined by multiple interactions between the pathogen and the host. In
the case of retroviruses, and in particular, the human immunodeficiency virus, the specific interaction of the envelope protein
with the host receptors and co-receptors is essential to gain entry in the cells. After entry, the success of retroviruses
to complete their life cycle depends on a complex interplay between the virus and host proteins. Indeed, the cell environment
is endowed with a number of factors that actively block distinct stage(s) in the microbial life cycle. Among these restriction
factors, Tripartite Motif-5α (TRIM5α) has been extensively studied; however, other TRIM family members have been demonstrated
to be anti-retroviral effector proteins. This article reviews, in particular, the current knowledge on the anti-retroviral
effects of TRIM5α and TRIM22. 相似文献
9.
《Redox report : communications in free radical research》2013,18(4):150-154
AbstractObjectivesRegular intake of green tea associates with lower DNA damage and increased resistance of DNA to oxidant challenge. However, in vitro pro-oxidant effects of green tea have been reported. Both effects could be mediated by hydrogen peroxide (H2O2) which is generated by autoxidation of tea catechins. In large amounts, H2O2 is genotoxic, but low concentrations could activate the redox-sensitive antioxidant response element (ARE) via the Keap-1/Nrf2 redox switch, inducing genoprotective adaptations. Our objective was to test this hypothesis.MethodsPeripheral lymphocytes from healthy volunteers were incubated for 30 minutes at 37°C in freshly prepared tea solutions (0.005, 0.01, 0.05%w/v (7, 14, 71 µmol/l total catechins) in phosphate buffered saline (PBS), with PBS as control) in the presence and absence of catalase (CAT). H2O2 in tea was measured colorimetrically. Oxidation-induced DNA lesions were measured by the Fpg-assisted comet assay.ResultsH2O2 concentrations in 0.005, 0.01, and 0.05% green tea after 30 minutes at 37°C were, respectively, ~3, ~7, and ~52 µmol/l. Cells incubated in 0.005 and 0.01% tea showed less (P < 0.001) DNA damage compared to control cells. Cells treated with 0.05% green tea showed ~50% (P < 0.001) more DNA damage. The presence of CAT prevented this damage, but did not remove the genoprotective effects of low-dose tea. No significant changes in expression of ARE-associated genes (HMOX1, NRF2, KEAP1, BACH1, and hOGG1) were seen in cells treated with tea or tea + CAT.ConclusionGenoprotection by low-dose green tea could be due to direct antioxidant protection by green tea polyphenols, or to H2O2-independent signalling pathways. 相似文献
10.
The mangrove system of Sine Saloum in Senegal is characterized by the lack of permanent river flow, in the context of the Sahelian drought which began in the 70s. The main environmental consequence is that Sine Saloum has become a so called reversed estuary with salinity increasing upstream and reaching 100 and more, with a mean salinity between 45–50. A threeyear survey of the juvenile fish community was undertaken with the aim of verifying whether or not this environment is still suitable as a nursery area for exploited fish populations. The main sampling gear used were small fykenets in addition to gill nets and a limited rotenone sampling. One of the six mangrove stations included in the survey exhibited a relatively high species diversity. This station is the only one where salinity may reach levels as low as 25 at the end of the rainy season, although salinity is much higher in the upstream region near this station. Such a low salinity is likely due to an underground freshwater connection or underwater springs. These observations highlight the relative importance of estuaries and mangroves in the nursery function. 相似文献
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Adam M. Finkel 《人类与生态风险评估》2011,17(4):754-787
For 30 years, more attention and resources have been expended on dissecting problems (risk assessment) than on evaluating actual solutions that reduce risks. The basic dogma holds that risk assessment must precede risk management. But there is an opposite and perhaps better way: the opening question should not be “How bad is the problem?” but “How good are the solutions we might apply to the problem?” Rethinking risk assessment in this context offers three classes of benefits over the status quo. First, it can help break the endless cycle of analysis: when the goal is to know enough to decide, rather than to know everything, natural stopping points emerge. Second, it can lead to more decisions that actually achieve risk reduction, rather than pronouncements about how much risk reduction would be optimal. Third, it can highlight ways to resolve multiple risks simultaneously, avoid needless and tragic risk-risk tradeoffs, and involve affected stakeholders in debating what should be done. Arguably, the longer the disembodied analysis of risk information is allowed to proceed, the more likely it is that the “problem” will be defined in a way that blunts the free-wheeling discussion of solutions, to the detriment of human health, the environment, and the economy. 相似文献
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Summary Roots with open apical organization are defined by not having specific tiers of initial cells in the root apical meristem; those with closed apical organization have specific initial tiers to which all cell files can be traced. An example of the clear organization of closed roots is the development protocol of the root cap and protoderm. The key event in differentiating these tissues is the T-division, a periclinal division of the root cap/protoderm (RCP) initial that establishes a module. Each module comprises two packets, the protoderm and peripheral root cap. Consecutive T-divisions of the same RCP initial produce up to five modules on average in a lineage of cells in white clover (Trifolium repens cv. Ladino), with all lineages around the circumference of the root dividing in waves to form one module prior to the next. On average, clover has approximately 32 axial protoderm and peripheral root cap cells in each module, and 32 RCP lineages. The occurrence of RCP T-divisions in white clover, a root with open apical organization, and the subsequent modular construction of the root cap and protoderm, provides a link between open and closed roots and suggests a common developmental feature that most roots of seed plants may share independent of their root meristem organization type. The open apical organization of the white clover root varies from roots with closed apical organization in that the RCP initials occur in staggered positions instead of connected to discrete tiers, and the peripheral root cap and columella daughter cells form additional layers of cells. White clover also forms root hairs on all protoderm cells irrespective of their position relative to the underlying cortical cells.Abbreviations RAM
root apical meristem
- RCP
root cap protoderm
- prc
peripheral root cap 相似文献
16.
“Candidatus Cardinium hertigii” (Bacteroidetes) is a maternally inherited endosymbiont known from several arthropods. Its mechanisms for persistence in host populations are mostly reproductive manipulation, though it has been occasionally reported to improve fitness parameters in several hosts. In Culicoides (Diptera: Ceratopogonidae) biting midges, the prevalence of “Candidatus Cardinium” infection was documented as moderate, with no detectable sex bias. We therefore investigated whether “Candidatus Cardinium” affects important fitness parameters, such as survival and body size, in Culicoides imicola, a dominant vector species. Field-collected midges were trapped and analyzed for survival under different environmental conditions and antibiotic treatment, taking into account “Candidatus Cardinium” infection status and parity status (i.e., parous or nulliparous). Additionally, wing lengths were measured as a proxy parameter for body size and analyzed together with “Candidatus Cardinium” infection data. The findings revealed no difference in survival of Culicoides infected with “Candidatus Cardinium” and that of uninfected midges in both parity states and under all tested conditions: optimal, starvation, heat, and antibiotic treatment. Beyond survival, no wing length difference was found for “Candidatus Cardinium”-infected versus uninfected midges. In aggregate, these findings support our conclusion that “Candidatus Cardinium” does not have an overt effect on the survival and size of adult C. imicola midges. “Candidatus Cardinium” may affect immature stages or may alter adult reproductive performance. 相似文献
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Organisms Diversity & Evolution - The paper continues the exploration of the morphological and functional diversity of male genitalia in Archaeognatha by the study of an undescribed... 相似文献
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Wei-Ming He Yulong Feng Wendy M. Ridenour Giles C. Thelen Jarrod L. Pollock Alecu Diaconu Ragan M. Callaway 《Oecologia》2009,159(4):803-815
Recent studies suggest that the invasive success of Centaurea maculosa may be related to its stronger allelopathic effects on native North American species than on related European species, one
component of the “novel weapons” hypothesis. Other research indicates that C. maculosa plants from the invasive range in North America have evolved to be larger and better competitors than conspecifics from the
native range in Europe, a component of the “evolution of increased competitive ability” hypothesis. These hypotheses are not
mutually exclusive, but this evidence sets the stage for comparing the relative importance of evolved competitive ability
to inherent competitive traits. In a competition experiment with a large number of C. maculosa populations, we found no difference in the competitive effects of C. maculosa plants from North America and Europe on other species. However, both North American and European C. maculosa were much better competitors against plants native to North America than congeners native to Romania, collected in areas
where C. maculosa is also native. These results are consistent with the novel weapons hypothesis. But, in a second experiment using just one
population from North America and Europe, and where North American and European species were collected from a broader range
of sites, competitive interactions were weaker overall, and the competitive effects of C. maculosa were slightly stronger against European species than against North American species. Also consistent with the novel weapons
hypothesis, (±)-catechin had stronger effects on native North American species than on native European species in two experiments.
Our results suggest that the regional composition of the plant communities being invaded by C. maculosa may be more important for invasive success than the evolution of increased size and competitive ability.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
19.
Robert A. Hahn 《Culture, medicine and psychiatry》1982,6(3):219-236
In different medical systems, notions of person, as patient and as healer, vary widely. An analysis of the talk of a practitioner of internal medicine in the U.S.A. reveals an understanding of patients as syndromes. The work of medicine is physiological integrity, distinct from personal and interpersonal integrity. It is suggested that the world view of this practitioner is consistent with the institutions of medicine in which he practices, and with historical movements in U.S. society and Western civilization more broadly. 相似文献
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Ernst Vitek 《Folia Geobotanica》1998,33(3):349-352
Problems and difficulties in the taxonomy ofEuphrasia (Scrophulariaceae) are discussed. They are partly due to autogamous breeding systems, but also due to patterns of ecological convergences. The use of taxonomic approaches to agamospermous complexes within autogamous groups in the genusEuphrasia is discussed and rejected because of producing unnecessary taxa for ephemeral variants. Also for the taxonomic treatment of agamospermous complexes in general the existence of a broad set of populations with stable morphological, ecological and/or geographical integrities should be the inevitable basis for describing of new taxa. 相似文献