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361.
Aeolian dunes controlled by regional climate have been formed in many coastal areas of the Mediterranean Sea during the Quaternary. Generally, they are formed under a landward-blowing wind, and comprise numerous reworked penecontemporaneous shallow-marine carbonate grains. Along the eastern mid-Adriatic Sea, late Pleistocene aeolian and alluvial sands occur as isolated patches in karstic depressions on several islands and the Pelje?ac Peninsula. At most localities, the sands consist of a mixture of mostly carbonate rock fragments and siliciclastic material. A higher proportion of shallow-marine bioclasts was found only at one locality. The terrestrial material was transported to the coastal area by at least two rivers: paleo-Cetina and paleo-Neretva River, and was subsequently reworked and transported by wind, resulting in aeolian deposition. Sandy units of various thicknesses exhibiting sharp erosional bedding planes and cross-bedding are interpreted as representing aeolian dunes and sand sheets controlled by a complex wind regime. The mineralogical composition at almost all localities indicates near-river flood plains as the main sand source. Although the area was affected by strong winds blowing landward and parallel to the coast, they significantly deviated due to the local topography produced by the tectonically deformed and karstified carbonate basement. In this way, the late Pleistocene aeolian deposits on the mid-Adriatic islands differ from deposits from most Quaternary Mediterranean coastal aeolian belts, as they contain very small quantities of penecontemporaneous shallow-marine carbonate grains and were deposited by winds blowing in varying directions instead of prevailing landward-blowing winds.  相似文献   
362.
Many physiological processes are limited to specific tissues or even specific cell types. Analysing entire plants or organs results in averaged data of all cell types contained in the sample; thus, specific metabolic functions cannot be assigned to individual cell types. A higher spatial resolution is required. By microdissecting plant organs, homogeneous material can be obtained. If a suitable amount of material is collected, standard analytical methods can be applied to elucidate cell type-specific processes. The collection of sufficient quantities of homogeneous material can be done by means of mechanical microdissection. This technique is a low-cost alternative to laser-coupled microdissection techniques. Here we describe a protocol for chisel-assisted mechanical microdissection of embedded plant material and demonstrate that the collected material is suitable to obtain nucleic acids and proteins.  相似文献   
363.
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