Z badań archeologicznych we wschodniej części Beskidu Małego

The article by Edelgarda and Eugeniusz Foltyn, which presents the results of an archaeological research in the eastern part of the Beskid Maly mountain range. The research was conducted in 1986, before the construction of a man-made lake in the area of the following villages: Chocznia, Jaroszowice, Mucharz, and Ponikiew. Nine archaeological sites were discovered then from the palaeolithic, and neolithic era, and from the so called late flint-digging period of the Bronze Age and early Iron Age. The finds may be interpreted as remains after the seasonal fishing of salmonoid fish undertaken by representatives of various prehistoric cultures

Uwagi o kulturze mikockiej na Górnym Śląsku : przyczynek do genezy kultury mikockiej w Europie Środkowej

Two sites of the Micoquian Culture are known in the literature from Upper Silesia: Pietrowice Wielkie site 23 (excavations from the period between the two World Wars; see for example J.K. Ko-złowski 1964a, s. 79, 161) and Dzierżysław site 1 (excavations of 1962-1992; see E.M. Fołtyn, E. Fołtyn, J.K. Kozłowski 2000). Recently it has been possible to gain access to four other sites of this culture which were also discovered in the Inter-War period: Cyprzanów site 3, Maków site 15, Pietrowice Wielkie site 8, Pietrowice Wielkie site 76 (see M. Fajer, E.M. Fołtyn, E. Fołtyn, J.K. Ko-złowski, in print). Apart from these, a relatively rich collection of finds was collected in 1993-1997 on site 49 in Pietraszyn (see M. Fajer, E.M. Fołtyn, E. Fołtyn, J.K. Kozłowski, in print). All these sites occur on the Głubczyce Plateau and form a sort of concentration in the catchment areas of the Psina and Troja rivers (Fig. 1). Site 49 at Pietraszyn which has produced the largest number of finds (72 items) is probably a workshop where bifacial tools were produced. Here several varieties of Upper Silesian erratic flint were used (Table 8). The inventory exhibits a twofold dominance of tools (46 items) over flakes (24 examples). The tools were made (see Table 1) of nodules (of slab form), waste and pieces (52.17%) and flakes (47.83%). Bifacial tools with surface retouch dominate over unifacial ones. The working techniques were bifacial and trifacial. The sections of the tools are flat-convex and double flat-convex (Table 2). Attention is drawn by the occurrence of 14 side-scrapers, 8 asymmetric knives, 3 hand-axes (Figs 2b, 4a, 3) — among them of Micoquian type and Faustkeilblatt, one hand-axe/knife (Fig. 5a) and 11 retouched flakes (Figs 2a, 13d, 18c). Among the side-scrapers, bifacial forms predominate (Figs 5b, 14a, b, 10a, 15a, b, 16, 17a) over unifacial ones (Figs lib, 12a, b, 13a, b, c). Among the asymmetric knives are three Prondnik-knives (Figs 4b, 6a, b), one Bockstein type knife (Fig. 7b) and other types (Figs 7a, c, 8a, b). These tools are supplemented by one denticulated notched piece, two atypical perforators (Fig. 18b), one burin-core (Fig. 18a), one flake-like blade with retouch on the tip (Fig. 17b), three half-finished of knife/side-scrapers (Figs 10b, 9a, b) and one half-finished leaf point (Fig. 11a). The flakes come mainly from bifacial working. They are charac-terized by differentiation of the dorsal surface (Table 3-4). Their butts are most often unprepared (Table 5), bulbs are detached, thinned or flat (Table 6) and the angle of striking is obtuse (Table 7). The assemblage also contains two unclassified half-products. They exhibit traces of the start of the use of Levalloisian (Fig. 2a) and discoidal core technique. From the technological-morphological point of view the material from Pietraszyn site 49 exhi-bits certain similarities with artefacts from Mesvin IV (M. Cahen, J. Michel 1986). The similarities concern the occurrence of analogous hand-axes and asymmetric knives and the knowledge of Leval-loisian techniques. They also have similar chronology. The remaining sites have produced small assemblages with rather eastern European affinities. From Cyprzanów site 3 come two Prondnik-knives (Fig. 20a, c) and one half-product of a bifacial tool (Fig. 20b) and a bilateral side-scraper. In the assemblage from Pietrowice Wielkie site 8 a knife resembling the form of a Wolgograd type (Fig. 19a) was found, as was a convex convergent side-scraper. The inventory is completed by an atypical knife with alternately retouched back from Maków site 15 and a trifacially-worked ovoid knife from Pietrowice Wielkie site 76 (Fig. 19b). On the basis of the materials discovered so far, one may define two chronological horizons in the development of the Micoquian Culture in Upper Silesia. The inventories of Dzierżysław site 1 layer 6 and Pietraszyn site 49 belong to the older horizon (Warta stage or the end of the Lublin stage). The chronological position of the finds from Dzierżysław site 1 is determined by their stratigraphic position (Older Loess lib according to J. Jersak 1991) as well as TL dates of the deposits in which they lay (E.M. Fołtyn, E. Fołtyn, J.K. Kozłowski 2000). The assignation of Pietraszyn site 49 to the earlier horizon is also determined by the geological context of the finds: in the upper layers of alluvia of the Warta stage terrace (Fig. 21a, b). The material from Cyprzanów site 3 can also be assigned to the pre-Eemian period. By contrast the assemblages from Pietrowice Wielkie sites 8,23,76 and Maków site 15 can most probably be linked with the later horizon of development of the Micoquian Culture (the Eemian stage — the lower level of the middle Vistula substage). This would be indicated by the state or preserva-tion of the artefacts, and the local stratigraphic situation at the place of discovery. The inventories from the archaeological sites at Dzierżysław site 1, Pietraszyn site 49 and Cy-przanów site 3 (?) seem to confirm the existence in central Europe of eastern Micoquian industries earlier than the Eemian stage. The theory of the western origin of the eastern Micoquian Culture (see for example F. Delpech, J.-M. Geneste, J.-Ph. Rigaud, J.-P. Texier 1995, s. 155) would seem to require re-examination

Osada wczesnośredniowieczna w Poborszowie, woj. opolskie

Osada w Poborszowie, stanowisko 8, jest jedną z wielu osad w dorzeczu górnej Odry, których chronologia przypada na starsze fazy wczesnego-średniowiecza. Jak większość z nich, rozpoznana została fragmentarycznie, w wyniku doraźnie podjętych ratowniczych prac wykopaliskowych. Do dokładniej zbadanych w tym rejonie należą osady otwarte z Dobrzenia Małego stanowisko 8, Łanów stanowisko 16, Warłowa stanowisko 7, Syryni stanowisko 1 i Pietrowic Wielkich stanowisko 8 oraz grodziska z Lubomi, Kamieńca i Chotebuza-Podobory (KOSTRZEWSKI 1939: 26-41; WOWRA 1970; KOURIL 1994: 71-167; FOŁTYN 2000: 32, 37, 49, 53-58, 63-64, tam dalsze odniesienia). Leżą one, z jednym wyjątkiem, w prawym pasie Górnego Nadodrza (Fragment tekstu)

Controlled Irradiative Formation of Penitentes

Spike-shaped structures are produced by light-driven ablation in very different contexts. Penitentes 1-4 m high are common on Andean glaciers, where their formation changes glacier dynamics and hydrology. Laser ablation can produce cones 10-100 microns high with a variety of proposed applications in materials science. We report the first laboratory generation of centimeter-scale snow and ice penitentes. Systematically varying conditions allows identification of the essential parameters controlling the formation of ablation structures. We demonstrate that penitente initiation and coarsening requires cold temperatures, so that ablation leads to sublimation rather than melting. Once penitentes have formed, further growth of height can occur by melting. The penitentes intially appear as small structures (3 mm high) and grow by coarsening to 1-5 cm high. Our results are an important step towards understanding and controlling ablation morphologies.Comment: Accepted for publication in Physical Review Letter

Angular dependent vortex pinning mechanisms in YBCO coated conductors and thin films

We present a comparative study of the angular dependent critical current density in YBa2Cu3O7 films deposited on IBAD MgO and on single crystal MgO and SrTiO3 substrates. We identify three angular regimes where pinning is dominated by different types of correlated and uncorrelated defects. We show that those regimes are present in all cases, indicating that the pinning mechanisms are the same, but their extension and characteristics are sample dependent, reflecting the quantitative differences in texture and defect density. In particular, the more defective nature of the films on IBAD turns into an advantage as it results in stronger vortex pinning, demonstrating that the critical current density of the films on single crystals is not an upper limit for the performance of the IBAD coated conductors.Comment: 14 pages, 3 figures. Submitted to AP

Thermal recrystallization of alpha-recoil damaged minerals of the pyrochlore structure type

Thermal recrystallization effects (heat of recrystallization and identification of phases formed), have been determined for naturally occurring members of the pyrochlore group which have received alpha doses of up to 4 X 10{sup 16} alphas/mg. The heats of recrystallization, E{sub t}, range from 125 to 210 J/g. Release of energy decreases as a function of crystallinity (estimated on the basis of the intensity of x-ray diffraction maxima), with the fully-metamict samples approaching 210 J/g. Lower measured values (40-125 J/g) are the result of alteration of the pyrochlores. Other metamict, complex oxides with stoichiometries of ABO{sub 4} and AB{sub 2}O{sub 6} have lower heats of recrystallization (40-85 J/g), and are easily distinguished from pyrochlore group minerals. Activation energies of recrystallization, E{sub a}, range between values of 0.29 to 0.97 eV, less than those measured for Pu-doped, synthetic zirconolites

The NMDA receptor activation by D-serine and glycine is controlled by an astrocytic Phgdh-dependent serine shuttle

Astrocytes express the 3-phosphoglycerate dehydrogenase (Phgdh) enzyme required for the synthesis of L-serine from glucose. Astrocytic L-serine was proposed to regulate NMDAR activity by shuttling to neurons to sustain D-serine production, but this hypothesis remains untested. We now report that inhibition of astrocytic Phgdh suppressed the de novo synthesis of L-and D-serine and reduced the NMDAR synaptic potentials and long-term potentiation (LTP) at the Schaffer collaterals-CA1 synapse. Likewise, enzymatic removal of extracellular L-serine impaired LTP, supporting an L-serine shuttle mechanism between glia and neurons in generating the NMDAR coagonist D-serine. Moreover, deletion of serine racemase (SR) in glutamatergic neurons abrogated D-serine synthesis to the same extent as Phgdh inhibition, suggesting that neurons are the predominant source of the newly synthesized D-serine. We also found that the synaptic NMDAR activation in adult SR-knockout (KO) mice requires Phgdh-derived glycine, despite the sharp decline in the postnatal glycine levels as a result of the emergence of the glycine cleavage system. Unexpectedly, we also discovered that glycine regulates D-serine metabolism by a dual mechanism. The first consists of tonic inhibition of SR by intracellular glycine observed in vitro, primary cultures, and in vivo microdialysis. The second involves a transient glycine-induce D-serine release through the Asc-1 transporter, an effect abolished in Asc-1 KO mice and diminished by deleting SR in glutamatergic neurons. Our observations suggest that glycine is a multifaceted regulator of D-serine metabolism and implicate both D-serine and glycine in mediating NMDAR synaptic activation at the mature hippocampus through a Phgdh-dependent shuttle mechanism