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1.
The recently revised guidelines for cholesterol management in Europe and the USA have focused attention on triglycerides and HDL cholesterol as risk factors for coronary heart disease. In the present review, I shall discuss therapeutic considerations in the treatment of patients with hypertriglyceridemia or low HDL cholesterol in the context of these new recommendations. I shall also consider recent studies in which the effect of triglyceride-lowering drugs on the concentrations and metabolism of lipoproteins in patients with dyslipidemia are evaluated.  相似文献   

2.
The importance given by various authors to the different environmental factors in their marine paleoecological analyses is briefly discussed. Applied as they are to the Lower Devonian of the Armorican Massif, these considerations allow to propose some reconstruction attempts and comment upon them. Set in the context of the paleogeographical evolution of Western Europe. the changes of these benthic associations point out that the single arrangement of the magnafacies is not sufficient to understand them.  相似文献   

3.
The current Northern Hemisphere migration systems are believed to have arisen since the last glaciation. In many cases, birds do not migrate strait from breeding to non‐breeding areas but fly via a detour. All western European populations of red‐backed shrikes Lanius collurio are assumed to reach their southern African wintering grounds detouring via southeast Europe. Based on theoretical considerations under an optimality framework this detour is apparently optimal. Here, we use individual geolocator data on red‐backed shrikes breeding in Spain to show that these birds do indeed detour via southeast Europe en route to southern Africa where they join other European populations of red‐backed shrikes and return via a similar route in spring. Disregarding potential wind assistance, the routes taken for the tracked birds in autumn were not optimal compared to crossing the barrier directly. For spring migration the situation was quite different with the detour apparently being optimal. However, when considering potential wind assistance estimated total air distances during autumn migration were overall similar and the barrier crossing shorter along the observed routes. We conclude that considering the potential benefit of wind assistance makes the route via southeast Europe likely to be less risky in autumn. However, it cannot be ruled out that other factors, such as following a historical colonisation route could still be important.  相似文献   

4.
《L'Anthropologie》2021,125(4):102914
Linking southeastern Europe and central Europe, the Danube Valley plays a key role in the models of the first colonization of Europe by anatomically modern humans about 40 thousand years ago (Danube Corridor hypothesis). The middle course of the river, the Carpathian Basin occupies a fundamental place in the search for archaeological evidences of the expansion of modern humans. Surveys carried out in northern Hungary in the last two decades have discovered numerous open-air sites whose lithic material can be attributed to the period concerned. Our excavations carried out in the region of Eger demonstrated the presence of the Aurignacian but also allowed the recognition of a macrolaminar industry of the Initial Upper Palaeolithic. The lithic material collected on the surface of the Andornaktálya 2 site provided rich assemblages of these two industries. The macrolaminar industry has techno-morphological connections with the leptolithic tools of Sokyrnytsia and Korolevo in Transcarpathian Ukraine. The Aurignacian industry has several characteristics in common with those of Košice-Barca and Seňa in southeastern Slovakia. Unfortunately, the chronological position of the macrolaminar and Aurignacian industries cannot be specified at the sites of the Eger region, although their age of Interpleniglacial seems evident from the stratigraphic considerations and the dating of the sediments. Despite these chronological inaccuracies, our results support the model, published by J.K. Kozłowski in 2010, of two waves of the immigration of modern humans across the Danube Corridor.  相似文献   

5.
The paddlefish (Polyodon spathula) was first introduced to Europe in 1974, mainly due to its potential for rearing in natural polyculture ponds and large temperate reservoirs. The information on the history of paddlefish aquaculture efforts in Europe is scarce, as well as data on current paddlefish aquaculture status and trends. In addition, there is a lack of data on its presence and potential establishment in the wild, while its invasive potential and associated risks and impacts are largely unknown. In order to evaluate its current status in Europe, we conducted a survey among scientists, aquaculture producers and other stakeholders, and reviewed literature and data on the Internet. Based on the results obtained, we discuss the potential and the challenges in European paddlefish aquaculture development, and analyze paddlefish invasive potential and risks associated with its naturalization. Paddlefish aquaculture is well established only regionally in Europe, but offers relatively high potential for further development in pond farms. Nevertheless, future development will require careful planning, especially regarding market development and improved marketing strategies. While paddlefish likely represents a low‐risk invader, improved control and reporting on trade and intentional and unintentional releases will be required. Given the lack of knowledge on potential impacts following its introduction, due caution seems highly advisable.  相似文献   

6.
Availability of bio-based chemicals, materials and energy at reasonable cost will be one of the forthcoming issues for the EU economy. In particular, the development of technologies making use of alternative resources to fossil fuels is encouraged by the current European research and innovation strategy to face the societal challenge of natural resource scarcity, fossil resource dependence and sustainable economic growth. In this respect, second- generation biorefineries, i.e. biorefineries fed with biowastes, appear to be good candidates to substitute and replace the present downstream processing scheme. Contrary to first-generation biorefineries, which make use of dedicated crops or primary cultivations to achieve such a goal, the former employ agricultural, industrial, zootechnical, fishery and forestry biowastes as the main feedstock. This leaves aside any ethical and social issue generated by first-generation approaches, and concomitantly prevents environmental and economical issues associated with the disposal of the aforementioned leftovers. Unfortunately, to date, a comprehensive and updated mapping of the availability and potential use of bioresources for second-generation biorefineries in Europe is missing. This is a lack that severely limits R&D and industrial applications in the sector. On the other hand, attempts at valorizing the most diverse biowastes dates back to the nineteenth century and plenty of information in the literature on their sustainable exploitation is available. However, the large majority of these investigations have been focused on single fractions of biowastes or single steps of biowaste processing, preventing considerations on an integrated and modular (cascade) approach for the whole valorization of organic leftovers. This review aims at addressing these issues by gathering recent data on (a) some of the main high-impact biowastes located in Europe and in particular in its Southern part, and (b) the bio-based chemicals, materials and fuels that can be produced from such residues. In particular, we focused on those key compounds referred to as “chemical platforms”, which have been indicated as fundamental to generate the large majority of the industrially relevant goods to date.  相似文献   

7.
This paper explores the manner in which the east of Europe has been theorized in the post cold war environment, and the implications for our understanding of the relationship between east and west. It argues that hegemonic discourses of neoliberalism lend a quality of inevitability to the integration of east into west, which in turn leads to a singular conception of Europe at the end of a trajectory of development. The paper argues that the relationship of western Europe to eastern Europe is more fruitfully explored through the conceptual framework of a center to its margins, which allows for a broader range of analysis on the issues — conceptual and implementational — at stake in transition processes, and which will allow for a theoretical exploration of where power is located and exercised. Because eastern Europe is understood in scholarly and policy communities as politically and geographically European, the study of postcommunist transition in Europe falls outside the purview of a development studies community that is increasingly focused on the emerging north/south divide. In a scholarly environment where the East/West divide no longer constitutes a salient focus of study, there is a need for the development of a framework that will provide a richer understanding of the reconstituted relationships being formed in Europe in the post-cold war environment. This paper argues that the social, economic, and political impact of disciplinary neoliberalism in eastern Europe can benefit from an analysis that takes into consideration the Eurocentric, disciplinary power that lies at the core of the transition process. Toward this end, it is necessary to query the discursive foundations of what constitutes the ‘properly European’ in order to develop a framework for a more fruitful course of analysis with respect to the relationship between Europe and its fluctuating eastern margins.  相似文献   

8.
Agri-environment schemes are an increasingly important tool for the maintenance and restoration of farmland biodiversity in Europe but their ecological effects are poorly known. Scheme design is partly based on non-ecological considerations and poses important restrictions on evaluation studies. We describe a robust approach to evaluate agri-environment schemes and use it to evaluate the biodiversity effects of agri-environment schemes in five European countries. We compared species density of vascular plants, birds, bees, grasshoppers and crickets, and spiders on 202 paired fields, one with an agri-environment scheme, the other conventionally managed. In all countries, agri-environment schemes had marginal to moderately positive effects on biodiversity. However, uncommon species benefited in only two of five countries and species listed in Red Data Books rarely benefited from agri-environment schemes. Scheme objectives may need to differentiate between biodiversity of common species that can be enhanced with relatively simple modifications in farming practices and diversity or abundance of endangered species which require more elaborate conservation measures.  相似文献   

9.
10.
The introduction and early spread of common ragweed (Ambrosia artemisiifolia L.) in Central and Eastern Europe were reconstructed based on a study of all herbarium specimens of common ragweed deposited at six herbaria in Austria, Hungary and Serbia. More than 450 specimens were examined and the oldest ones, collected from 1907 to 1927, were used to map the historical spread of this highly allergenic invasive weed in this region. The herbarium records back-date the first known introduction of this noxious weed to Central and Eastern Europe as well as its early spread on the Danube-Tisza Plain, and in the North-Eastern part of Hungary. The data also confirm that the introduction of common ragweed to Central and Eastern Europe took place later than its introduction to the Western part of the continent.  相似文献   

11.
In this publication, we review the biology, ecology, invasion history, impacts and management options of Emerald ash borer (EAB) Agrilus plannipennis, with a particular focus on its invasion in Europe. Agrilus planipennis (EAB) is a wood‐boring beetle native to East Asia. Having caused massive damages on ash species in North America in the last decades, it was first recorded in Europe in 2003 in Russia (Moscow). All ash (Fraxinus) species native to Europe and North America are known to be susceptible to EAB attacks, which cause high tree mortality even among formerly healthy trees. Recorded expansion rates are between 2.5 and 80 km/year in North America and between 13 and 41 km/year in European Russia. Given current expansion rates, EAB is expected to reach Central Europe within 15–20 years. A combination of mechanical, biological and chemical control and phytosanitary measures may reduce its impact, which nevertheless most likely will be substantial. There is an urgent need to identify native enemies in Europe, to test suitable biocontrol agents and to develop early detection and management measures. Although it is obvious that EAB will become a major pest in Europe, early and dedicated response will likely be able to reduce the level of ash mortality, and thus improve the opportunity for long‐term survival of ash as an important component in European forests.  相似文献   

12.
WHO is under pressure from all sides to justify its existence. Donors want to know what they are getting for their money, and health professionals question the relevance of the organisation''s work. The pressure to justify itself is perhaps strongest of all in Europe, where most member countries have fully fledged health infrastructures and high overall levels of health. Now there is the additional threat of encroachment into the field of public health by the European Union. The disintegration of the Soviet bloc has given WHO''s regional office in Europe a new sense of purpose and led to a major shift in resources towards the countries of central and eastern Europe. But WHO''s critics are calling for a different shift in the way its European office works: from its current concentration on broad based policy issues to the nitty-gritty of health care management and delivery.  相似文献   

13.
The silver fir woolly adelgid, Dreyfusia nordmannianae, is the most severe pest occurring on Abies nordmanniana in Central and Northern Europe. The adelgid is particularly damaging to trees in Christmas tree plantations. Dreyfusia nordmannianae is native to the Caucasus region and alien to Europe, where its natural enemy complex is less diverse compared to its area of origin. Mitochondrial and nuclear DNA sequence data from the samples of D. nordmannianae collected in its native range and Europe and from the samples of Dreyfusia piceae and Dreyfusia prelli collected in Europe and North America were examined for phylogenetic structure. There was no evidence of differentiation, suggesting that these Dreyfusia species have recently diverged or require taxonomic revision. All existing published and unpublished reports on natural enemies of D. nordmannianae in its place of origin were reviewed, with the purpose of selecting agents for classical biological control in Europe. The literature review suggested that the most promising agent was the Chamaemyiidae fly, Leucopis hennigrata. A new survey in D. nordmannianae's area of origin – Turkey, Georgia and Russia – showed that L. hennigrata was present in all localities. It was particularly abundant in Turkey, where its impact on populations of D. nordmannianae appears to be high. Its use as a biological control agent is discussed, as well as other biological control strategies.  相似文献   

14.
Harmonia axyridis: an environmental risk assessment for Northwest Europe   总被引:1,自引:0,他引:1  
In this paper, we summarize the international situation with respect to environmental risk assessment for biological control agents. Next, we apply a recently designed, comprehensive risk evaluation method consisting of a stepwise procedure to evaluate the environmental risks of Harmonia axyridis in Northwest Europe. This resulted in the very clear conclusion that H. axyridis is a potentially risky species for Northwest Europe, because it is able to establish, it has a very wide host range including species from other insect orders and even beyond the class of Insecta, it may feed on plant materials, it can cover large distances (>50 km per year), it does move into non-target areas, it may attack many non-target species including beneficial insects and insects of conservation concern, its activities have resulted in the reduction of populations of native predators in North America, it is known as a nuisance in North America and recently also in Northwest Europe, and it may develop as a pest of fruit in North America. Considering the H. axyridis case, current knowledge would lead to the conclusion that, although the predator is capable to effectively control several pest species, its risks are manifold and it should, thus, not have been released in Northwest Europe. At the time of the first releases in Nortwest Europe in 1995, the available scientific literature made clear that H. axyridis is a large sized polyphagous predator and has a great reproductive capacity in comparison with other ladybird beetles, and that there was a need to study non-target effects because of its polyphagous behaviour. In retrospect, this information should have been sufficient to reject import and release of this species, but it was apparently ignored by those who considered release of this predator in Northwest Europe. The case of Harmonia releases in Northwest Europe underlines that there is an urgent need for harmonized, world-wide regulation of biological control agents, including an information system on risky natural enemy species.  相似文献   

15.
The 2010 census round has shown a significant growth in the number of countries collecting ethnic and racial data as a consequence of the increasing consciousness of their internal ethnic diversity and to implement more active equality policies addressing ethno-racial discrimination. However, Europe is not part of this dynamic: almost nothing has changed on the ethnic statistics’ frontline in between the two census rounds. This article addresses some of the justification for the enduring resistance of “statistical blindness” to ethno-racial diversity in Europe, locating it mainly in the strategy to erase race from the public sphere as a leverage to combat racism. The limits of this strategy in the context of mass migration from former colonial empires where racial subordination and classification have been produced and developed are discussed. Europe should ultimately face its past domination (rebranded but still active today) without silencing its consequences.  相似文献   

16.
17.
The Campanian Ignimbrite (CI) volcanic eruption was the most explosive in Europe in the last 200,000 years. The event coincided with the onset of an extremely cold climatic phase known as Heinrich Event 4 (HE4) approximately 40,000 years ago. Their combined effect may have exacerbated the severity of the climate through positive feedbacks across Europe and possibly globally. The CI event is of particular interest not only to investigate the role of volcanism on climate forcing and palaeoenvironments, but also because its timing coincides with the arrival into Europe of anatomically modern humans, the demise of Neanderthals, and an associated major shift in lithic technology. At this stage, however, the degree of interaction between these factors is poorly known, based on fragmentary and widely dispersed data points. In this study we provide important new data from Eastern Europe which indicate that the magnitude of the CI eruption and impact of associated distal ash (tephra) deposits may have been substantially greater than existing models suggest. The scale of the eruption is modelled by tephra distribution and thickness, supported by local data points. CI ashfall extends as far as the Russian Plain, Eastern Mediterranean and northern Africa. However, modelling input is limited by very few data points in Eastern Europe. Here we investigate an unexpectedly thick CI tephra deposit in the southeast Romanian loess steppe, positively identified using geochemical and geochronological analyses. We establish the tephra as a widespread primary deposit, which blanketed the topography both thickly and rapidly, with potentially catastrophic impacts on local ecosystems. Our discovery not only highlights the need to reassess models for the magnitude of the eruption and its role in climatic transition, but also suggests that it may have substantially influenced hominin population and subsistence dynamics in a region strategic for human migration into Europe.  相似文献   

18.
Cioclovina (Romania): affinities of an early modern European   总被引:1,自引:0,他引:1  
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19.
We argue that insect species conservation at large scales should take account of the distribution of genetic diversity among populations. Maintenance of genetic diversity may be vital in retaining a species' adaptive capacity and evolutionary potential. We illustrate the concept using the example of the large copper butterfly Lycaena dispar in Europe. This species has become extinct in parts of its range and is declining rapidly in others, whilst conversely, increasing in many areas. The latter has recently reduced its conservation status. Mitochondrial DNA analysis is used to construct a phylogeography from a preliminary sample set obtained from across Europe. A cytochrome b fragment of 402 base pairs was sequenced and 10 haplotypes were found. Relatedness among populations suggest that those from northern and central Europe are closely related and probably form one evolutionary significant unit (ESU) reflecting post-glacial colonization from southeast Europe. In contrast, the sample from Italy is divergent and should be considered a separate ESU. Our results, combined with ecological data, suggest that conservation action for this species should be targeted on specific regions and populations.  相似文献   

20.
The Golden eagle (Aquila chrysaetos) is among the most widespread of the birds of prey, covering basically the whole Palaearctic from Europe and North Africa through Asia and Japan, to the North American continent. Only few studies have addressed the species’ genetic structure and the consequences of its demographic history so far, and none of them has covered larger areas of the distribution range. Our present study aims at closing this gap. Based on 283 samples (mostly feathers collected in the field or from museum collections) across the species’ distribution, but with a focus on Europe, we uncover the phylogeography of the Golden eagle. Results imply a phylogeographic split between mainly Northern Europe, Continental Asia, Japan and North America on the one hand and Central–Southern Europe on the other. The observed pattern is likely to be caused by the Last Ice Age, when the population survived in two reproductively isolated glacial refugia. Repopulation of Northern Europe occurred from a presumed Asian refugium, whereas the Alpine range was probably repopulated from a refugium in the Mediterranean region. In Eastern Europe, the Mediterranean and Alpine region we find a co‐occurrence of both lineages that heavily influences the local genetic diversity. This pattern is unlike that in most other large raptors in which usually a western and an eastern Eurasian lineage have been recovered.  相似文献   

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