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The procerebrum of stylommatophoran snails produces nitric oxide (NO)-modulated oscillatory local field potentials which are considered the basis of olfactory information processing. Although the function of NO is well characterized in the PC, the identification and distribution of NO synthase (NOS) has not known completely. In the present study, applying a mammalian anti-NOS antibody, a 170 kDa molecular weight NOS-like protein was demonstrated in the procerebrum homogenate of Helix pomatia. NOS-like immunolabeling of the globuli cells, the internal and terminal neuropils displayed an identical distribution compared to that of NADPH-diaphorase reactive material, confirming the specificity of immunohistochemistry. The detailed characteristics of the immunostaining (different intensity of the neural perikarya, a gradual appearance in the terminal neuropil and in the axon bundles of the tentacular nerve, as well as an intense, homogeneous distribution of NOS-like immunoreactivity in the internal neuropil) suggest that NOS is expressed constitutively, maintaining a high level of the enzyme in neuropil areas. NOS accumulation in the internal neuropil suggests that NO plays an important role in delivering olfactory signals extrinsic to the procerebrum, and integrating them with other sensory modalities, respectively. Our results are the first, demonstrating unequivocally the presence of NOS and resolving its differential distribution in the Helix procerebrum.
Distribution of the potassium channel of Kv4.3 type was investigated in the central nervous system (CNS) of Helix pomatia by immunohistochemistry. Immunopositive neurons were found widely distributed in the CNS, present mostly in smaller groups in the different central ganglia but not in the visceral ganglion. Labeled fibers were characteristic for not only the neuropils of all ganglia but also the connective tissue sheath around the CNS and the aorta wall were richly innervated. Western blot analysis revealed a clear identity with the mammalian Kv4.3 subunit, suggesting an evolutionary conserved structure of this channel type. Our preliminary results provide a steady basis for further experiments aiming partly at the identification of other potassium channel types and partly the ultrastructural localization of Kv4.3.
Let A be a set of n real numbers such that the number of distinct twofold sums is a n. We show that the number of twofold products is = c n 2/ (a4 log n), and the number of quotients is = c n 2/ min (a6, a4 log n) with some absolute constant c. For bounded a this gives the correct order of magnitude for the quotients. For sums we think that the correct order is n2/ (log n)a with some a<1, perhaps with 2 log 2 -1, as a result of Pomerance and Sárközy suggests. We also give more general inequalities for sums, products and quotients formed with different sets. The proofs use geometric tools, mainly the Szemerédi-Trotter inequality.
Summary
Elérhetoség
Abstract
The aim of the current paper is to map minerals mainly of Carpathian obsidian glasses by nuclear microprobe based on the particle induced X-ray emission (PIXE) providing analytical data on them for the first time. Some samples from Armenia, Greece are also involved to make a comparison with the Carpathian specimens. The following minerals are identified and analyzed: pyrrhotite, chalcopyrite, pyrite, zircon, pyroxene, biotite, plagioclase feldspar, and anhydrite. On the basis of rock-forming silicate minerals, some petrologic processes are outlined. With the identification of accessory minerals (anhydrite, pyrrhotite, chalcopyrite, pyrite), some geological conclusions are also drawn.
Obsidian samples from different localities of various geologic settings (Armenia, Hungary, Iceland, Mexico, Slovakia and Turkey) were analyzed by particle induced gamma-ray emission (PIGE) technique and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Samples from Mexico and Iceland show higher alkali and REE content as well as higher Nb and Ta abundances than the other samples. Discrimination diagrams show samples from Mexico and Iceland to belong to WPG. The position of the samples from the Tokaj Mts is also definite, and it corresponds to the expectation (VAG or VAG+syn-COLG fields). Using a Li-B diagram the obsidian samples can be distinguished according to their geographic distribution. By means of a Ce-Ti diagram, obsidian from the Tokaj Mts can be divided into three groups that may correspond to the archeometrical C2E, C2T and C1 groups. Phenocrysts in the obsidian samples from the Tokaj Mts, and the Aragats Mts (Armenia) were detected and analyzed by micro-PIXE (proton induced X-ray emission) method. In this way silicate minerals (zircon, pyroxene, biotite, plagioclase feldspars), ore minerals (chalcopyrite, pyrrhotite, pyrite), and other non-silicate mineral (anhydrite) were identified.
