2,190 research outputs found

    Greigite from rocks : biogenic or non-biogenic?

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    Oribatid assemblies of tropical high mountains on some points of the “Gondwana-Bridge” – a case study

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    This work is the first part of a series of studies, which introduces the methodological possibilities of coenological and zoogeographical indication and – following the climate, vegetation and elevation zones – the pattern-describing analysis of the main Oribatid sinusia of the world explored till our days.This current work is a case-study, which displays the comparison of 9 examination sites from 3 different geographical locations. On each location, three vegetation types have been examined: a plain rain-forest, a mossforest and a mountainous paramo. Analyses are based on the hitherto non-published genus-level database and coenological tables of the deceased János Balogh professor. Occurrence of 18 genera is going to be published as new data for the given zoogeographical region

    Investigation of the relation between the colorant content and the colour characteristics of the edible oil based extracts of the paprika grist

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    During our work we performed the color measurements of the oily extracts from the Hungarian paprika grist. We defined a color index from the C'lELab color coordinates, by means of which the rank in the redness sequence of the oily colorant extract can be evaluated. Wc established that there was a tight linear relation between the colorant content of the grist expressed in ASTA value and the color index of the oily extract. In case of the oily extracts the coloi index calculated from the data of the color measurement is adaptable to evaluate the coloring capability and via this ii is appropriate for the color classification of the paprika grist

    Late Miocene to present day structural development of the Polish segment of the Outer Carpathians

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    This paper presents a few pieces of evidence on neotectonic structural evolution of the Polish segment of the Outer Carpathians. During the Late Neogene, structural development was largely controlled by normal faulting and block uplift. However, there are also indications of compressional stress setting, at least during the Pliocene and particularly within the medial and eastern parts of the belt. In the Quaternary, in turn, structural development has been mainly controlled by compressional stress arrangement, with \sigma _{1} orientated roughly perpendicular to the belt. The Pliocene-Quaternary tectonic mobility of the Polish Outer Carpathians has been relatively weak and mostly of thin-skinned character. Normal faults were formed on the margins of intramontane basins and in the western part of the belt. Rates of uplift of individual structures were variable and the amount of uplift was the greatest in the Late Pliocene and Early Quaternary times. Geomorphologically-detected zones of uplift are relatively narrow and arranged subparallel or under small angle in respect to the strike of principal thrusts and frontal parts of large slices. Such an arrangement is interpreted as resulting from the steepening of frontal thrusts due to horizontal compression within the overthrust flysch nappes. This hypothesis is confirmed by the results of recent break-out and GPS studies, as well as by focal solutions of some Outer Carpathian earthquakes

    A salsolinol dopaminerg transzmisszióban betöltött fiziológiás szerepének vizsgálata = Examination of the physiological role of salsolinol in dopaminergic neurotransmission

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    Korábban kimutattuk, hogy a hipofízis közti-hátsó lebenyének (NIL) prolaktin (PRL) ürítő hatásért a salsolinol (SAL) felelős. A PRL-szint emelkedéssel párhuzamosan a SAL az eminentia medianaban (ME) csökkenti, míg az elülső lebenyben (AL) növeli cAMP szintet. A SAL-nak egy szerkezeti analógja, az 1MeDIQ képes gátolni a szopási ingerre és a stresszre bekövetkező PRL szint emelkedést. Mindezek alátámasztják korábbi feltevésünket, hogy a SAL az a régóta keresett élettanilag is jelentős prolaktoliberin. Az 1MeDIQ az amfetamin (AMPH)-hoz hasonló psziho-stimuláns hatással is rendelkezik, növeli a plazma katecholamin-szinteket. A perifériás szimpatikus beidegzések műtéti vagy farmakológiás (chlorisondamine) lézióját követően fellépő változások a SAL hatásában világosan jelzik, hogy az 1MeDIQ hatásában a norepinefrin (NE)-erg rendszer kulcsszerepet játszik. A PRL felszabadító hatása mellett a SAL csökkenti a stressz és az 1MeDIQ kiváltotta plazma NE és epinefrin (E) emelkedést. Hasonló kölcsönhatást találtunk az AMPH és a SAL prolaktin elválasztásra gyakorolt hatásában is. A szimpatikus idegelemek által beidegzett szervekben, mint a pitvarban, lépben, májban, vagy az ovariumban, a SAL szelektíven csökkenti a dopamin (DA) koncentrációját. SAL-nak ez a hatása a kivédhető AMPH-előkezeléssel. Összefoglalva, a SAL és az AMPH között kölcsönhatás állapítható meg az elülső lebenyi PRL-ürítés és a szimpatikus végződésekben zajló katecholamin-metabolizmus vonatkozásában egyaránt. | We have previously shown that salsolinol (SAL) is responsible for the prolactin (PRL) releasing activity detected in the neurointermediate lobe (NIL) of the pituitary gland. SAL can induce a decrease of cAMP level in the median eminence (ME) and an increase in the anterior lobe (AL). A structural analogue of SAL, 1MeDIQ, can inhibit the elevation of plasma PRL induced by physiological stimuli like suckling or stress. All these data support our assumption that SAL may be the physiologically relevant prolactoliberin. 1MeDIQ has a psycho-stimulant action as well, which is similar to the effect of amphetamine (AMPH) i.e. induces an increase in plasma catecholamine concentrations. Surgical or pharmacological (chlorisondamine) lesions of peripheral sympathetic innervations clearly indicate that norepinephrin (NE)-erg system has pivotal role in the action of 1MeDIQ. SAL, besides its PRL releasing activity, can significantly decrease stress and 1MeDIQ induced increase in plasma NE and epinephrine (E) levels. There is an interaction between AMPH and SAL on pituitary PRL release too. SAL treatment results in a selective decrease in DA content of sympathetically innervated organs like atrium, spleen, liver, ovaries, and salivary gland. This effect of SAL is prevented by AMPH pretreatment. It is clear that there is a mutual interaction between SAL and AMPH not only on PRL release, but their interaction is obvious on the catecholamine ?metabolism? of nerve terminals as well

    On the Persistence of the Electromagnetic Field

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    According to the standard realistic interpretation of classical electrodynamics, the electromagnetic field is conceived as a real physical entity existing in space and time. The problem we address in this paper is how to understand this spatiotemporal existence, that is, how to describe the persistence of a field-like physical entity like electromagnetic field. First, we provide a formal description of the notion of persistence: we derive an “equation of persistence” constituting a necessary condition that the spatiotemporal distributions of the fundamental attributes of a persisting physical entity must satisfy. We then prove a theorem according to which the vast majority of the solutions of Maxwell's equations, describing possible spatiotemporal distributions of the fundamental attributes of the electromagnetic field, violate the equation of persistence. Finally, we discuss the consequences of this result for the ontology of the electromagnetic field

    Accelerating analysis of Boltzmann equations using Gaussian mixture models: Application to quantum Bose-Fermi mixtures

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    The Boltzmann equation is a powerful theoretical tool for modeling the collective dynamics of quantum many-body systems subject to external perturbations. Analysis of such a model gives access to linear response properties such as collective modes and transport coefficients that characterize a system, but often proves intractable due to computational costs associated with multidimensional integrals describing collision processes. Here, we present a method to resolve this bottleneck, enabling efficient study of the linear response of a broad class of quantum many-body systems whose behavior can be described using a Boltzmann equation. Specifically, we demonstrate that a Gaussian mixture model can accurately represent equilibrium distribution functions and, when combined with the variational method of moments framework, allows efficient computation of collision integrals. We apply this method to investigate the collective behavior of a quantum Bose-Fermi mixture of cold atoms in a cigar-shaped trap, focusing on monopole and quadrupole collective modes above the Bose-Einstein transition temperature. We find a rich phenomenology that spans interference effects between bosonic and fermionic collective modes, dampening of these modes, and the emergence of hydrodynamics in various parameter regimes. Typical spectral functions exhibit Fano interference profiles, systems with dilute fermions manifest behavior reminiscent of Bose polarons, and systems with comparable bosonic and fermionic densities display hallmarks of hydrodynamics such as mode-locking. These effects are readily verifiable with modern cold-atom experiments, and the method developed here opens the door to understanding the collective behavior of many fundamental and technologically-relevant systems.Comment: 32 page (19 pages of the main text), 10 figures (7 are in the main text
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