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31.
32.
The Forgotten Rural Landscapes of Central and Eastern Europe   总被引:1,自引:0,他引:1  
Interactions between nature and man – the underlying forces in landscape – have over time caused diversity. Usually, geographers and landscape ecologists deal with spatial diversity; in this paper, we would like to also consider temporal diversity. We argue that Central and Eastern European landscapes (using the examples of Estonia, Hungary, Poland and Slovenia) are much more diverse in time (layers) than Western European ones. This difference requires the use of different indicators in order to measure and study landscapes and special problems, threats, and possibilities of management and future development – but most important is the consideration of different perceptions. We also show that this diversity reduces the readability of landscapes, creating miscommunication and a transformation of meanings. We further argue that the link between humans and landscape is lost in Central and Eastern European countries due to temporal diversity, and that this link will be created anew in a globalizing world. To overcome alienation, we need slightly different classifications/typologies for each country in this region, with the aim of a sound future management of cultural landscapes.  相似文献   
33.
Palang  Hannes  Külvik  Mart  Printsmann  Anu  Storie  Joanna T. 《Landscape Ecology》2019,34(7):1807-1823
Context

Two approaches to study landscape change have been exploited: one that tries to study the developments that have happened in the past, and another that tries to foresee future.

Objectives

We analyse how this dual approach can help understanding landscape change, how people relate to it in general, what their expectations and preferences are. We also discuss the usefulness of path dependency theory, cultural sustainability, and cultural ecosystem services approaches in understanding the management of a historical cultural landscape.

Methods

First, we revisit a 1999 scenario study that outlined the possible trajectories of change prior Estonian accession to the European Union in 2004. Then, through series of studies we track the wider context of the landscape changes, analysing the results from the interviews and combining those with the visible results. We seek to answer whether or not the landscape changes that occurred followed any of the past scenarios, and if people’s preferences changed.

Results

The dynamics of realisation of different scenarios was not straightforward. However, people showed clear preference towards landscapes that carried signs of the continuation of rural life. What was not foreseen when designing the scenarios was the upsurge of local identity creating the links with the past.

Conclusions

In this Estonian traditional cultural landscape, stewardship, culture and cultural ecosystem services, or nature’s contribution to people as IPBES prefers to call this now, define what caring for the landscape involves.

  相似文献   
34.
Long-distance free-space distribution of quantum entanglement   总被引:1,自引:0,他引:1  
We demonstrate the distribution of quantum entanglement via optical free-space links to independent receivers separated by 600 m, with no line of sight between each other. A Bell inequality between those receivers is violated by more than four standard deviations, confirming the quality of the entanglement. This outdoor experiment represents a step toward satellite-based distributed quantum entanglement.  相似文献   
35.
Epilepsy afflicts 1% of humans and 5% of dogs. We report a canine epilepsy mutation and evidence for the existence of repeat-expansion disease outside humans. A canid-specific unstable dodecamer repeat in the Epm2b (Nhlrc1) gene recurrently expands, causing a fatal epilepsy and contributing to the high incidence of canine epilepsy. Tracing the repeat origins revealed two successive events, starting 50 million years ago, unique to canid evolution. A genetic test, presented here, will allow carrier and presymptomatic diagnosis and disease eradication. Clinicopathologic characterization establishes affected animals as a model for Lafora disease, the most severe teenage-onset human epilepsy.  相似文献   
36.
Cachexia is a multifactorial wasting syndrome most common in patients with cancer that is characterized by the uncontrolled loss of adipose and muscle mass. We show that the inhibition of lipolysis through genetic ablation of adipose triglyceride lipase (Atgl) or hormone-sensitive lipase (Hsl) ameliorates certain features of cancer-associated cachexia (CAC). In wild-type C57BL/6 mice, the injection of Lewis lung carcinoma or B16 melanoma cells causes tumor growth, loss of white adipose tissue (WAT), and a marked reduction of gastrocnemius muscle. In contrast, Atgl-deficient mice with tumors resisted increased WAT lipolysis, myocyte apoptosis, and proteasomal muscle degradation and maintained normal adipose and gastrocnemius muscle mass. Hsl-deficient mice with tumors were also protected although to a lesser degree. Thus, functional lipolysis is essential in the pathogenesis of CAC. Pharmacological inhibition of metabolic lipases may help prevent cachexia.  相似文献   
37.
This study was carried out to examine differences in microstructure and texture of fresh and smoked farmed Atlantic salmon Salmo salar L. fillets with different biological characteristics. The left fillet was analysed fresh and compared with the salted and smoked right fillet from each individual fish. Light microscopy and image analysing techniques were used to study both transversal and longitudinal sections of the muscle. The fish muscle fibres shrank during the salting and smoking process, but sarcomere length did not change. After smoking, a considerable number of fat globules were dispersed among the muscle fibres. The biological characteristics studied were based upon diploid and triploid fish held in both sea cages and land‐based tanks. Different starvation times were used and one group was stressed during slaughter. The cross‐sectional area of muscle fibres from triploid fish was found to be larger than from diploid fish, both in fresh and smoked fillets.  相似文献   
38.
The need to boost agricultural production in the coming decades in a climate change scenario requires new approaches for the development of new crop varieties that are more resilient and more efficient in the use of resources. Crop wild relatives (CWRs) are a source of variation for many traits of interest in breeding, in particular tolerance to abiotic and biotic stresses. However, their potential in plant breeding has largely remained unexploited. CWRs can make an effective contribution to broadening the genetic base of crops and to introgressing traits of interest, but their direct use by breeders in breeding programs is usually not feasible due to the presence of undesirable traits in CWRs (linkage drag) and frequent breeding barriers with the crop. Here we call for a new approach, which we tentatively call ‘introgressiomics’, which consists of mass scale development of plant materials and populations with introgressions from CWRs into the genetic background of crops. Introgressiomics is a form of pre-emptive breeding and can be focused, when looking for specific phenotypes, or un-focused, when it is aimed at creating highly diverse introgressed populations. Exploring germplasm collections and identifying adequate species and accessions from different genepools encompassing a high diversity, using different strategies like the creation of germplasm diversity sets, Focused identification of germplasm strategy (FIGS) or gap analysis, is a first step in introgressiomics. Interspecific hybridization and backcrossing is often a major barrier for introgressiomics, but a number of techniques can be used to potentially overcome these and produce introgression populations. The generation of chromosome substitution lines (CSLs), introgression lines (ILs), or multi-parent advanced inter-cross (MAGIC) populations by means of marker-assisted selection allows not only the genetic analysis of traits present in CWRs, but also developing genetically characterized elite materials that can be easily incorporated in breeding programs. Genomic tools, in particular high-throughput molecular markers, facilitate the characterization and development of introgressiomics populations, while new plant breeding techniques (NPBTs) can enhance the introgression and use of genes from CWRs in the genetic background of crops. An efficient use of introgressiomics populations requires moving the materials into breeding pipelines. In this respect public–private partnerships (PPPs) can contribute to an increased use of introgressed materials by breeders. We hope that the introgressiomics approach will contribute to the development of a new generation of cultivars with dramatically improved yield and performance that may allow coping with the environmental changes caused by climate change while at the same time contributing to a more efficient and sustainable agriculture.  相似文献   
39.
40.

Key message

Historic transfer of larch from Alpine sources to Southern and Eastern Carpathians has been verified by means of nuclear genetic markers. Tyrolean populations can be differentiated into a north-western and south-eastern group, while Romanian populations are separated according to the Southern and Eastern Carpathians. Low-level introgression from Alpine sources is found in autochthonous Carpathian populations.

Context

Large scale human mediated transfer of forest reproductive material may have strongly modified the gene pool of European forests. Particularly in European larch, large quantities of seeds from Central Europe were used for plantations in Southern and Eastern Europe starting in the mid nineteenth century.

Aims

Our main objective was to provide DNA marker based evidence for the anthropogenic transfer of Alpine larch reproductive material to native Carpathian populations.

Methods

We studied and compared 12 populations (N?=?771) of Larix decidua in the Alps (Austria, Italy) and in the Southern and Eastern Carpathians (Romania) using 13 microsatellites.

Results

High genetic diversity (He?=?0.752; RS?=?9.4) and a moderate genetic differentiation (FST?=?0.13; GST?=?0.28) among populations were found; Alpine and Carpathian populations were clearly separated by clustering methods. A Tyrolean origin of plant material was evident for one out of four adult Romanian populations. In the transferred population, a genetic influence from Carpathian sources was found neither in adults nor in juveniles, while the natural regeneration of two Romanian populations was genetically affected by Alpine sources to a minor degree (2.2 and 2.9% allochthonous individuals according to GeneClass and Structure, respectively).

Conclusion

Tracing back of plant transfer by means of genetic tools is straightforward, and we propose further studies to investigate gene flow between natural and transferred populations.
  相似文献   
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