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81.
The integration of the environmental dimension into sectoral and regional policies constitutes a dominant concern of the current EU strategy for sustainable development. Thus, physical planning as an instrument of environmental policy and its combination with environmental planning, both at a policy as well as implementation level is a key pursuit in almost all European countries. In Greece, the adoption of a concept about a rational and unified approach of physical and environmental planning has met with many difficulties. The aim of this paper is to contribute towards a critical approach of recent developments, mainly in the field of the institutional framework for spatial and environmental planning in Greece.  相似文献   
82.
Junctional epidermolysis bullosa, Herlitz variant (junctional EB-Herlitz) is a lethal autosomal recessive skin disorder currently amenable to prenatal diagnosis only by direct analysis of fetal skin. However, elevated levels of alpha-fetoprotein, as well as the presence of acetylcholinesterase in amniotic fluid, have been associated with other severe fetal genodermatoses. Fetal skin samplings were performed in ten pregnancies at risk for fetal junctional EB-Herlitz, with three fetuses affected on the basis of electron microscopic detection of blisters within the lamina lucida and abnormal hemidesmosomes. In neither affected nor unaffected pregnancies were maternal serum or amniotic fluid alpha-fetoprotein levels elevated. Moreover, alphafetoprotein levels in both maternal serum and amniotic fluid were not statistically different comparing affected and unaffected fetuses. Acetylcholinesterase was not present in the amniotic fluid samples of the three affected pregnancies. Unlike other severe fetal genodermatoses, neither alpha-fetoprotein nor acetylcholinesterase was predictive of junctional EB-Herlitz.  相似文献   
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The lethal effects of aluminum ion (Al3+) in tilapia (Oreochromis niloticus) raised in concrete tanks were investigated. Tilapias were fed daily with commercial feed enriched with known concentrations of Al3+ and analyzed by differential pulse anodic stripping voltammetry (DPASV). The concentrations of Al3+ in feces, water, muscle tissue, viscera, and heads were determined every 3 months for a period of 365 days. The Tilapia head was the most affected tissue by Al3+. In general, Al3+ bioaccumulation reached the lethal dose (LD50) after 335 days of experiment as follows: 34.9?mg?kg?1 (muscle tissue), 88.2?mg?kg?1 (viscera), and 126.9?mg?kg?1 (head without gills). After determining Cu2+, Zn2+, and Ca2+ by absorption spectrometry, a decrease in the Ca2+ concentration was noted in the head during the experimental period. These observations were associated with the occurrence of a decalcification in the bone tissue in the presence of Al3+. In contrast, it was found that Zn2+ ions may act as a protective agent against Al3+-induced contamination.  相似文献   
85.
It has been repeatedly stressed that the biological effectiveness of chromium depends entirely on its oxidation state. The present work compares the histological effects of ingested trivalent and hexavalent chromium compounds on the mouse testes. The results showed comparable data of food consumption and gain in body weight. Both compounds produced ambiguous levels of degeneration in the outmost cellular layers of a number of seminiferous tubules, reduced the number of spermatogonia per tubule and the sperm count, and caused significant increases in the percentage of morphologically abnormal sperms. Generally, all these effects were more pronounced in animals which ingested the hexavalent chromium.  相似文献   
86.
Indigenous trees play key roles in West African landscapes, such as the néré tree (Parkia biglobosa (Jacq.) R.Br. ex G.Don). We applied social–ecological network analysis to understand the social–ecological interactions around néré. We documented the benefits néré provides and the multiple social interactions it creates amongst a large range of actors. The flows of rights over the trees and benefits from them formed two hierarchical networks, or cascades, with different actors at the top. The two forms of power revealed by the two cascades of rights and benefits suggest possible powers and counter-powers across gender, ethnicity, and age. We documented how the tree catalyses social interactions across diverse groups to sustain vital social connections, and co-constitute places, culture, and relationships. We argue that a paradigm shift is urgently needed to leverage the remarkable untapped potential of indigenous trees and Cultural Keystone Species in current global restoration and climate change agendas.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01733-z.  相似文献   
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Environmental Science and Pollution Research - The expansion of agricultural activities causes habitat loss and fragmentation and the pollution of natural ecosystems through the intense use of...  相似文献   
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