127 research outputs found

    Spectral changes of brain activity in rat offspring exposed to aluminium during gestation and lactation

    Get PDF
    Exposure to aluminium during gestation causes changes in mammalian brain development and behavior. Our aim was to perform spectral analysis on electrocortical activity of Sprague Dawley male pups (30±3 days of age) whose mothers were treated with aluminium during gestation and lactation. There was a higher presence of power spectra in the delta range of parietal electrocortical activity, a lower presence in the theta range and increased values of the parameter DT as the ratio of delta to theta range in pups indirectly exposed to aluminium (whose mothers were drinking a 0.5% water solution of aluminium chloride during the gestation and lactation periods), compared to controls

    Spectral changes of brain activity in rat offspring exposed to aluminium during gestation and lactation

    Get PDF
    Exposure to aluminium during gestation causes changes in mammalian brain development and behavior. Our aim was to perform spectral analysis on electrocortical activity of Sprague Dawley male pups (30±3 days of age) whose mothers were treated with aluminium during gestation and lactation. There was a higher presence of power spectra in the delta range of parietal electrocortical activity, a lower presence in the theta range and increased values of the parameter DT as the ratio of delta to theta range in pups indirectly exposed to aluminium (whose mothers were drinking a 0.5% water solution of aluminium chloride during the gestation and lactation periods), compared to controls.Izlaganje dejstvu aluminijuma tokom gestacije i laktacije može dovesti do promena u razviću mozga i ponašanja kod sisara. Naš cilj je bio da se uradi spektralna analiza elektrokortikalne aktivnosti mladih Sprague Dawley pacova muškog pola (starosti 30±3 dana) čije su majke bile tretirane aluminijumom tokom gestacije i laktacije. U poređenju sa kontrolom, kod mladih pacova koji su bili indirektno trovani aluminijumom (čije su majke pile 0,5 % vodeni rastvor AlCl3 tokom gestacionog i laktacionog perioda) postoji veća zastupljenost delta ritma aktivnosti kore velikog mozga, manje prisustvo teta ritma, kao i porast parametra DT kao odnos između delta i teta opsega.Projekat ministarstva br. 14302

    Reduction of carbon monoxide emission from a solid-fuel thermo-accumulation furnace

    Get PDF
    Many households in Serbia, using electric thermo-accumulation furnaces for heating, have been forced to find an alternative solution, due to a significant increase in electricity prices during the last decade. A possible solution is replacing electric heating appliances with the solid fuel-fired ones. A prototype of a new concept of thermo-accumulation solid fuel-fired furnace has been developed to meet these growing needs, providing electricity saving together with considerable environmental benefits. Two strategies for reduction of carbon monoxide emission are examined in the paper: application of Pt/Al2O3 catalyst, in the form of 3 ± 0.3 mm spheres, providing further combustion of flue gases within the furnace, as well as an additional emission reduction by means of the air excess control. Experimental investigations of the catalyst influence on the conversion of carbon monoxide have been done for different operation regimes and positions of the catalyst. The paper presents selected results regarding carbon monoxide emission during wood and coal combustion. Investigations suggest a considerable effect of the catalyst and a strong influence of the catalyst position within the furnace to carbon monoxide emission reduction. In addition, experimental tests have been conducted to asses the effect of the air excess control in the furnace on carbon monoxide emission. The amount of combustion air, the flue gas flow rate, and the fuel feeding regime have been adjusted in order to keep the flue gas oxygen content in a relatively narrow range, thus obtaining controlled combustion conditions and lower carbon monoxide emission. In this way, the furnace has been made able to respond to the changes in heating needs, fuel quality and other parameters, which is advantageous in comparison with similar solid-fuel fired furnaces

    Graph products of spheres, associative graded algebras and Hilbert series

    Full text link
    Given a finite, simple, vertex-weighted graph, we construct a graded associative (non-commutative) algebra, whose generators correspond to vertices and whose ideal of relations has generators that are graded commutators corresponding to edges. We show that the Hilbert series of this algebra is the inverse of the clique polynomial of the graph. Using this result it easy to recognize if the ideal is inert, from which strong results on the algebra follow. Non-commutative Grobner bases play an important role in our proof. There is an interesting application to toric topology. This algebra arises naturally from a partial product of spheres, which is a special case of a generalized moment-angle complex. We apply our result to the loop-space homology of this space.Comment: 19 pages, v3: elaborated on connections to related work, added more citations, to appear in Mathematische Zeitschrif

    Upper critical field, penetration depth, and depinning frequency of the novel high-temperature superconductor LaFeAsO0.9_{0.9}F0.1_{0.1} studied by microwave surface impedance

    Get PDF
    Temperature and magnetic field dependent measurements of the microwave surface impedance of superconducting LaFeAsO0.9_{0.9}F0.1_{0.1} (\Tc \approx 26K) reveal a very large upper critical field (Bc256B_{\rm c2} \approx 56T) and a large value of the depinning frequency (f06f_{0}\approx 6GHz); together with an upper limit for the effective London penetration depth, λeff200nm\lambda_{\rm eff} \le 200 \rm nm, our results indicate a strong similarity between this system and the high-TcT_{\rm c} superconducting cuprates.Comment: 4 pages, 6 figures, minor corrections and rephrasin

    Spectral changes of brain activity in rat offspring exposed to aluminium during gestation and lactation

    Get PDF
    Exposure to aluminium during gestation causes changes in mammalian brain development and behavior. Our aim was to perform spectral analysis on electrocortical activity of Sprague Dawley male pups (30±3 days of age) whose mothers were treated with aluminium during gestation and lactation. There was a higher presence of power spectra in the delta range of parietal electrocortical activity, a lower presence in the theta range and increased values of the parameter DT as the ratio of delta to theta range in pups indirectly exposed to aluminium (whose mothers were drinking a 0.5% water solution of aluminium chloride during the gestation and lactation periods), compared to controls.Izlaganje dejstvu aluminijuma tokom gestacije i laktacije može dovesti do promena u razviću mozga i ponašanja kod sisara. Naš cilj je bio da se uradi spektralna analiza elektrokortikalne aktivnosti mladih Sprague Dawley pacova muškog pola (starosti 30±3 dana) čije su majke bile tretirane aluminijumom tokom gestacije i laktacije. U poređenju sa kontrolom, kod mladih pacova koji su bili indirektno trovani aluminijumom (čije su majke pile 0,5 % vodeni rastvor AlCl3 tokom gestacionog i laktacionog perioda) postoji veća zastupljenost delta ritma aktivnosti kore velikog mozga, manje prisustvo teta ritma, kao i porast parametra DT kao odnos između delta i teta opsega.Projekat ministarstva br. 14302

    Hidden magnetic excitation in the pseudogap phase of a model cuprate superconductor

    Full text link
    The elucidation of the pseudogap phenomenon of the cuprates, a set of anomalous physical properties below the characteristic temperature T* and above the superconducting transition temperature Tc, has been a major challenge in condensed matter physics for the past two decades. Following initial indications of broken time-reversal symmetry in photoemission experiments, recent polarized neutron diffraction work demonstrated the universal existence of an unusual magnetic order below T*. These findings have the profound implication that the pseudogap regime constitutes a genuine new phase of matter rather than a mere crossover phenomenon. They are furthermore consistent with a particular type of order involving circulating orbital currents, and with the notion that the phase diagram is controlled by a quantum critical point. Here we report inelastic neutron scattering results for HgBa2CuO4+x (Hg1201) that reveal a fundamental collective magnetic mode associated with the unusual order, and that further support this picture. The mode's intensity rises below the same temperature T* and its dispersion is weak, as expected for an Ising-like order parameter. Its energy of 52-56 meV and its enormous integrated spectral weight render it a new candidate for the hitherto unexplained ubiquitous electron-boson coupling features observed in spectroscopic studies.Comment: 8 pages, 3 figures, with supplementary information and figure

    Abscisic Acid Insensitive 4 transcription factor is an important player in the response of Arabidopsis thaliana to two-spotted spider mite (Tetranychus urticae) feeding.

    Get PDF
    Plants growing in constantly changeable environmental conditions are compelled to evolve regulatory mechanisms to cope with biotic and abiotic stresses. Effective defence to invaders is largely connected with phytohormone regulation, resulting in the production of numerous defensive proteins and specialized metabolites. In our work, we elucidated the role of the Abscisic Acid Insensitive 4 (ABI4) transcription factor in the plant response to the two-spotted spider mite (TSSM). This polyphagous mite is one of the most destructive herbivores, which sucks mesophyll cells of numerous crop and wild plants. Compared to the wild-type (Col-0) Arabidopsis thaliana plants, the abi4 mutant demonstrated increased susceptibility to TSSM, reflected as enhanced female fecundity and greater frequency of mite leaf damage after trypan blue staining. Because ABI4 is regarded as an important player in the plastid-to-nucleus retrograde signalling process, we investigated the plastid envelope membrane dynamics using stroma-associated fluorescent marker. Our results indicated a clear increase in the number of stroma-filled tubular structures deriving from the plastid membrane (stromules) in the close proximity of the site of mite leaf damage, highlighting the importance of chloroplast-derived signals in the response to TSSM feeding activity
    corecore