Analysis of indole derivatives in methanolic extracts from mycelium of Agaricus bisporus cultured in vitro on liquid Oddoux medium

Methanolic extracts obtained from biomass of Agaricus bisporus (J.E. Lange) Imbach cultured in vitro were analyzed for qualitative and quantitative composition of non-hallucinogenic indole compounds in order to compare their amount with fruiting bodies of these species. Extracts demonstrated to contain six indole compounds. Contents of individual compounds ranged from 0.01 to 21.33 mg/100 g d.w. in biomass from in vitro cultures. The quantitatively dominating compounds included: 5-hydroxytryptophan (12.50 mg/100 g d.w.), Ltryptophan (14.00 mg/100 g d.w.) and serotonin (7.00 mg/100 g d.w.). Total content of the remaining indole compounds under analysis in the study was 55.32 mg/100 g d.w.Po raz pierwszy zidentyfikowane i ilościowo oznaczone zostały związki indolowe w kulturach in vitro Agaricus bisporus na płynnym podłożu wg Oddoux. Analiza wykazała, że ekstrakty metanolowe otrzymane z grzybni zawierają sześć związków indolowych: L -tryptofan, 5 - hydroksytryptofan, serotoninę, melatoninę, tryptaminę i 5-metylotryptamię. Zawartości poszczególnych składników w biomasie z kultur in vitro były zróżnicowane w zakresie od 0,01 do 21,33 mg/100 g s. m. Dominującymi ilościowo związkami były: 5-hydroksytryptofan (12,50 mg/100 g s. m.), L-tryptofan (14,00 mg/100 g) i serotonina (7,00 mg/100 g). Całkowita zawartość związków indolowych w badanym materiale wynosiła 55,32 mg/100 g s. m. Biomasa z kultur in vitro badanego gatunku jest dobrym źródłem 5-hydroksytryptofanu i L- tryptofanu. Kultury in vitro A. bisporus mogą być wykorzystane jako model do badań nad akumulacją i metabolizmem związków indolowych

Biologically active compounds from selected aphyllophorales mycelial cultures

The obtained results confirm the hypothesis that mycelial cultures of domestic species of aphyllophorales are able to accumulate biologically active metabolites.Uzyskane wyniki wskazują, że przebadane kultury mycelialne krajowych gatunków grzybów afylloforoidalnych są zdolne do akumulacji metabolitów aktywnych biologicznie

Small -x behavior of the non-singlet and singlet structure functions g_1

Explicit expressions for the non-singlet and singlet structure functions g_1 at the small $x$-region are obtained. They include the total resummation of double-logarithmic contributions and accounting for the running QCD coupling effects. We predict that both the non-singlet and singlet g_1 asymptotically ~ x^{- \Delta}, with the singlet intercept = 0.86 and being more than twice larger than the non-singlet intercept = 0.4. The impact of the initial quark and gluon densities on the sign of g_1 at x << 1 is discussed.Comment: Talk given at Xth Workshop on high energy spin physics, Dubna, Russia, September,16-20, 2003. LateX 9pp, 4 fig

Electron-ion coupling in semiconductors beyond Fermi's golden rule

In the present work, a theoretical study of electron-phonon (electron-ion) coupling rates in semiconductors driven out of equilibrium is performed. Transient change of optical coefficients reflects the band gap shrinkage in covalently bonded materials, and thus, the heating of atomic lattice. Utilizing this dependence, we test various models of electron-ion coupling. The simulation technique is based on tight-binding molecular dynamics. Our simulations with the dedicated hybrid approach (XTANT) indicate that the widely used Fermi's golden rule can break down describing material excitation on femtosecond time scales. In contrast, dynamical coupling proposed in this work yields a reasonably good agreement of simulation results with available experimental data

Compton spectra of atoms at high x-ray intensity

Compton scattering is the nonresonant inelastic scattering of an x-ray photon by an electron and has been used to probe the electron momentum distribution in gas-phase and condensed-matter samples. In the low x-ray intensity regime, Compton scattering from atoms dominantly comes from bound electrons in neutral atoms, neglecting contributions from bound electrons in ions and free (ionized) electrons. In contrast, in the high x-ray intensity regime, the sample experiences severe ionization via x-ray multiphoton multiple ionization dynamics. Thus, it becomes necessary to take into account all the contributions to the Compton scattering signal when atoms are exposed to high-intensity x-ray pulses provided by x-ray free-electron lasers (XFELs). In this paper, we investigate the Compton spectra of atoms at high x-ray intensity, using an extension of the integrated x-ray atomic physics toolkit, \textsc{xatom}. As the x-ray fluence increases, there is a significant contribution from ionized electrons to the Compton spectra, which gives rise to strong deviations from the Compton spectra of neutral atoms. The present study provides not only understanding of the fundamental XFEL--matter interaction but also crucial information for single-particle imaging experiments, where Compton scattering is no longer negligible.Comment: 24 pages, 10 figures. This is an author-created, un-copyedited version of an article accepted for publication in the special issue of "Emerging Leaders" in J. Phys. B: At. Mol. Opt. Phys. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from i

Multistep transition of diamond to warm dense matter state revealed by femtosecond X-ray diffraction

Diamond bulk irradiated with a free-electron laser pulse of 6100 eV photon energy, 5 fs duration, at the $\sim 19-25$ eV/atom absorbed doses, is studied theoretically on its way to warm dense matter state. Simulations with our hybrid code XTANT show disordering on sub-100 fs timescale, with the diffraction peak (220) vanishing faster than the peak (111). The warm dense matter formation proceeds as a nonthermal damage of diamond with the band gap collapse triggering atomic disordering. Short-living graphite-like state is identified during a few femtoseconds between the disappearance of (220) peak and the disappearance of (111) peak. The results obtained are compared with the data from the recent experiment at SACLA, showing qualitative agreement. Challenges remaining for the accurate modeling of the transition of solids to warm dense matter state and proposals for supplementary measurements are discussed in detail.Comment: Preprint, submitte

Hydrodynamic model for expansion and collisional relaxation of x-ray laser-excited multi-component nanoplasma

The irradiation of an atomic cluster with a femtosecond x-ray free-electron laser pulse results in a nanoplasma formation. This typically occurs within a few hundreds femtoseconds. By this time the x-ray pulse is over, and the direct photoinduced processes no longer contributing. All created electrons within the nanoplasma are thermalized. The nanoplasma thus formed is a mixture of atoms, electrons and ions of various charges. While expanding, it is undergoing electron impact ionization and three-body recombination. Below we present a hydrodynamic model to describe the dynamics of such multi-component nanoplasma. The model equations are derived by taking the moments of the corresponding Boltzmann kinetic equations. We include the equations obtained, together with the source terms due to electron impact ionization and three-body recombination, in our hydrodynamic solver. Model predictions for a test case: expanding spherical Ar nanoplasma are obtained. With this model we complete the two-step approach to simulate x-ray created nanoplasmas, enabling computationally efficient simulations of their picosecond dynamics. Moreover, the hydrodynamic framework including collisional processes can be easily extended for other source terms and then applied to follow relaxation of any finite non-isothermal multi-component nanoplasma with its components relaxed into local thermodynamic equilibrium.Comment: 12 pages, 4 figures. This article has been accepted by Physics of Plasmas. After it is published, it will be found at http://scitation.aip.org/content/aip/journal/po

A molecular-dynamics approach for studying the non-equilibrium behavior of x-ray-heated solid-density matter

When matter is exposed to a high-intensity x-ray free-electron-laser pulse, the x rays excite inner-shell electrons leading to the ionization of the electrons through various atomic processes and creating high-energy-density plasma, i.e., warm or hot dense matter. The resulting system consists of atoms in various electronic configurations, thermalizing on sub-picosecond to picosecond timescales after photoexcitation. We present a simulation study of x-ray-heated solid-density matter. For this we use XMDYN, a Monte-Carlo molecular-dynamics-based code with periodic boundary conditions, which allows one to investigate non-equilibrium dynamics. XMDYN is capable of treating systems containing light and heavy atomic species with full electronic configuration space and 3D spatial inhomogeneity. For the validation of our approach we compare for a model system the electron temperatures and the ion charge-state distribution from XMDYN to results for the thermalized system based on the average-atom model implemented in XATOM, an ab-initio x-ray atomic physics toolkit extended to include a plasma environment. Further, we also compare the average charge evolution of diamond with the predictions of a Boltzmann continuum approach. We demonstrate that XMDYN results are in good quantitative agreement with the above mentioned approaches, suggesting that the current implementation of XMDYN is a viable approach to simulate the dynamics of x-ray-driven non-equilibrium dynamics in solids. In order to illustrate the potential of XMDYN for treating complex systems we present calculations on the triiodo benzene derivative 5-amino-2,4,6-triiodoisophthalic acid (I3C), a compound of relevance of biomolecular imaging, consisting of heavy and light atomic species