Showing papers by "Jan Kochanowski University published in 2011"

Highly anisotropic and strongly dissipative hydrodynamics for early stages of relativistic heavy-ion collisions

Abstract: We introduce a new framework of highly anisotropic hydrodynamics that includes dissipation effects Dissipation is defined by the form of the entropy source that depends on the pressure anisotropy and vanishes for the isotropic fluid With a simple ansatz for the entropy source obeying general physical requirements, we are led to a nonlinear equation describing the time evolution of the anisotropy in purely longitudinal boost-invariant systems Matter that is initially highly anisotropic approaches naturally the regime of the perfect fluid Thus, the resulting evolution agrees with the expectations about the behavior of matter produced at the early stages of relativistic heavy-ion collisions The equilibration is identified with the processes of entropy production

Validation of the Joensuu risk criteria for primary resectable gastrointestinal stromal tumour – The impact of tumour rupture on patient outcomes

Abstract: Background Approval of imatinib for adjuvant treatment of gastrointestinal stromal tumours (GIST) raised discussion about accuracy of prognostic factors in GIST and the clinical significance of the available risk stratification criteria. Methods We studied the influence of a new modification of the NIH Consensus Criteria (the Joensuu risk criteria), NCCN-AFIP criteria, and several clinicopathological factors, including tumour rupture, on relapse-free survival (RFS) in a prospectively collected tumour registry series consisting of 640 consecutive patients with primary, resectable, CD117-immunopositive GIST. The median follow-up time after tumour resection was 39 months. None of the patients received adjuvant imatinib. Results The median RFS time after surgery was 50 months. In univariable analyses, high Joensuu risk group, tumour mitotic count >5/50 HPF, size >5 cm, non-gastric location, tumour rupture (7% of cases; P = 0.0014) and male gender had adverse influence on RFS. In a multivariable analysis mitotic count >5/50HPF, tumour size >5 cm and non-gastric location were independent adverse prognostic factors. Forty, 151, 86 and 348 patients were assigned according to the Joensuu criteria to very low, low, intermediate and high risk groups and had 5-year RFS of 94%, 94%, 86% and 29%, respectively. Conclusion The Joensuu criteria, which include 4 prognostic factors (tumour size, site, mitotic count and rupture) and 3 categories for the mitotic count, were found to be a reliable tool for assessing prognosis of operable GIST. The Joensuu criteria identified particularly well high risk patients, who are likely the proper candidates for adjuvant therapy.

Gender differentiation in methods of suicide attempts

Abstract: Background: Suicide is an important public health problem worldwide, especially due to an increasing rate of suicides committed by violent methods. This study compared and assessed the methods used in suicide attempts (but no completed suicides) as undertaken by men and women and investigated the possible role of gender in the selection of suicide method. Material/Methods: The study was conducted among persons who attempted suicide by various methods and were admitted to hospital. The study population comprised 147 participants (33 males and 114 females) aged between 14 and 33 years. Results: The most prevalent methods of suicide attempts were pharmacological drugs abuse (42.31%) and exsanguination (25.64%), and the least frequent were poisoning and throwing oneself under a moving car (1.28%). The findings revealed that the female subjects tended to choose pharmacological drugs overdose and exsanguination as the suicide method, while males more frequently used hanging and asphyxia. Females also used a greater number of different suicide methods. Conclusions: The study results indicate that women as a group more frequently attempted suicide rather than actually committing it, whereas men were more likely to complete suicides and choose more violent suicide methods; thus, women are the "attempters" and "survivors" of suicide attempts. The study findings may have implications for therapy and prevention of suicide, and suggest that psychotherapeutic activities should be tailored to the psychological and personality traits associated with gender identity. Language: en

Measurements of Cross Sections and Charged Pion Spectra in Proton-Carbon Interactions at 31 GeV/c

Abstract: Interaction cross sections and charged pion spectra in p+C interactions at 31 GeV/c were measured with the large-acceptance NA61/SHINE spectrometer at the CERN SPS. These data are required to improve predictions of the neutrino flux for the T2K long-baseline neutrino oscillation experiment in Japan. A set of data collected during the first NA61/SHINE run in 2007 with an isotropic graphite target with a thickness of 4% of a nuclear interaction length was used for the analysis. The measured p+C inelastic and production cross sections are 257.2 {+-} 1.9 {+-} 8.9 and 229.3 {+-} 1.9 {+-} 9.0 mb, respectively. Inclusive production cross sections for negatively and positively charged pions are presented as functions of laboratory momentum in ten intervals of the laboratory polar angle covering the range from 0 up to 420 mrad. The spectra are compared with predictions of several hadron production models.

Strongly intensive quantities

Abstract: Analysis of fluctuations of hadron production properties in collisions of relativistic particles profits from use of measurable intensive quantities which are independent of system size variations. The first family of such quantities was proposed in 1992; another is introduced in this paper. Furthermore we present a proof of independence of volume fluctuations for quantities from both families within the framework of the grand canonical ensemble. These quantities are referred to as strongly intensive ones. Influence of conservation laws and resonance decays is also discussed.

Toxicity of Silver Nanomaterials in Higher Eukaryotes

Abstract: The rapid expansion of nanotechnology promises to have significant benefits to society, yet there is increasing concern that exposure to nanoparticles (particles typically in vitro and in vivo uptake, biodistribution, and toxicity of AgNPs. Emphasis is placed on the systematization of data over animal and cell models, organs examined, doses applied, the type of particle administration, and the time of examination.

Torqued fireballs in relativistic heavy-ion collisions

Abstract: We show that the fluctuations in the wounded-nucleon model of the initial stage of relativistic heavy-ion collisions, together with the natural assumption that the forward- (backward-) moving wounded nucleons emit particles preferably in the forward (backward) direction, lead to an event-by-event torqued fireball. The principal axes associated with the transverse shape are rotated in the forward region in the opposite direction than in the backward region. On the average, the standard deviation of the relative torque angle between the forward and backward rapidity regions is $~$${20}^{\ifmmode^\circ\else\textdegree\fi{}}$ for the central and ${10}^{\ifmmode^\circ\else\textdegree\fi{}}$ for the midperipheral collisions. The hydrodynamic expansion of a torqued fireball leads to a torqued collective flow, yielding, in turn, torqued principal axes of the transverse-momentum distributions at different rapidities. We propose experimental measures, based on cumulants involving particles in different rapidity regions, which should allow for a quantitative determination of the effect from the data. To estimate the nonflow contributions from resonance decays we run Monte Carlo simulations with therminator, a thermal heavy-ion generator. If the event-by-event torque effect is found in the data, it will support the assumptions concerning the fluctuations in the early stage of the fireball formation, as well as the hypothesis of the asymmetric rapidity shape of the emission functions of the moving sources in the nucleus-nucleus collisions.

THERMINATOR 2: THERMal heavy IoN generATOR 2

Abstract: We present an extended version of THERMINATOR, a Monte Carlo event generator dedicated to studies of the statistical production of particles in relativistic heavy-ion collisions. The package is written in C++ and uses the CERN ROOT data-analysis environment. The largely increased functionality of the code contains the following main features: 1) The possibility of input of any shape of the freeze-out hypersurface and the expansion velocity field, including the 3+13+1-dimensional profiles, in particular those generated externally with various hydrodynamic codes. 2) The hypersurfaces may have variable thermal parameters, which allow studies departing significantly from the mid-rapidity region where the baryon chemical potential becomes large. 3) We include a library of standard sets of hypersurfaces and velocity profiles describing the RHIC Au + Au data at sNN=200 GeV for various centralities, as well as those anticipated for the LHC Pb + Pb collisions at sNN=5.5 TeV. 4) A separate code, FEMTO-THERMINATOR, is provided to carry out the analysis of the pion–pion femtoscopic correlations which are an important source of information concerning the size and expansion of the system. 5) We also include several useful scripts that carry out auxiliary tasks, such as obtaining an estimate of the number of elastic collisions after the freeze-out, counting of particles flowing back into the fireball and violating causality (typically very few), or visualizing various results: the particle pTpT-spectra, the elliptic flow coefficients, and the HBT correlation radii. Program summary Program title:THERMINATOR 2 Catalogue identifier: ADXL_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXL_v2_0.html Program obtainable from: CPC Program Library, Queenʼs University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 423 444 No. of bytes in distributed program, including test data, etc.: 2 854 602 Distribution format: tar.gz Programming language:C++ with the CERN ROOT libraries, BASH shell Computer: Any with a C++ compiler and the CERN ROOT environment, ver. 5.26 or later, tested with Intel Core2 Duo CPU E8400 @ 3 GHz, 4 GB RAM Operating system: Linux Ubuntu 10.10 x64 (gcc 4.4.5) ROOT 5.26 Linux Ubuntu 11.04 x64 (gcc Ubuntu/Linaro 4.5.2-8ubuntu4) ROOT 5.30/00 (compiled from source) Linux CentOS 5.2 (gcc Red Hat 4.1.2-42) ROOT 5.30/00 (compiled from source) Mac OS X 10.6.8 (i686-apple-darwin10-g++-4.2.1) ROOT 5.30/00 (for Mac OS X 10.6 x86-64 with gcc 4.2.1) cygwin-1.7.9-1 (gcc gcc4-g++-4.3.4-4) ROOT 5.30/00 (for cygwin gcc 4.3) RAM: • 30 MB therm2 events • 150 MB therm2 femto Classification: 11.2 Catalogue identifier of previous version: ADXL_v1_0 Journal reference of previous version: Comput. Phys. Comm. 174 (2006) 669 External routines: CERN ROOT (http://root.cern.ch/drupal/) Does the new version supersede the previous version?: Yes Nature of problem: Particle production via statistical hadronization in relativistic heavy-ion collisions. Solution method: Monte Carlo simulation, analyzed with ROOT. Reasons for new version: The increased functionality of the code contains the following important features. The input of any shape of the freeze-out hypersurface and the expansion velocity field, including the 3+13+1-dimensional profiles, in particular those generated externally with the various popular hydrodynamic codes. The hypersurfaces may have variable thermal parameters, which allows for studies departing significantly from the mid-rapidity region. We include a library of standard sets of hypersurfaces and velocity profiles describing the RHIC Au + Au and the LHC Pb+PbPb+Pb data. A separate code, FEMTO-THERMINATOR, is provided to carry out the analysis of femtoscopic correlations. Summary of revisions: THERMINATOR 2 incorporates major revisions to encompass the enhanced functionality. • Classes: The Integrator class has been expanded and a new subgroup of classes defined. ∘ Model and abstract class: These classes are responsible for the physical models of the freeze-out process. The functionality and readability of the code has been substantially increased by implementing each freeze-out model in a different class. ∘ The Hypersurface class was added to handle the input form hydrodynamic codes. The hydro input is passed to the program as a lattice of the freeze-out hypersurface. That information is stored in the .xml files. • Input: THERMINATOR 2 programs are now controlled by *.ini type files. The programs parameters and the freeze-out model parameters are now in separate ini files. • Output: ∘ The event files generated by the therm2_events program are not backward compatible with the previous version. The event*.root file structure was expanded with two new TTree structures. From the particle entry it is possible to back-trace the whole cascade. ∘ Event text output is now optional. ∘ The ROOT macros produce the *.eps figures with physics results, e.g. the pT-spectra, the elliptic-flow coefficient, rapidity distributions, etc. ∘ The THERMINATOR HBT package creates the ROOT files femto*.root (therm2_femto) and hbtfit*.root (therm2_hbtfit). • Directory structure: The directory structure has been reorganized. Source code resides in the build directory. The freeze-out model input files, event files, ROOT macros are stored separately. The THERMINATOR 2 system, after installation, is able to run on a cluster. • Scripts: The package contains a few BASH scripts helpful when running e.g. on a cluster the whole system can be executed via a single script. Additional comments: Typical data file size: default configuration. • 45 MB/500 events; • 35 MB/correlation file (one kTkT bin); • 45 kB/fit file (projections and fits). Running time: Default configuration at 3 GHz. • primordial multiplicities 70 min (calculated only once per case); • 8 min/500 events; • 10 min – draw all figures; • 25 min/one kTkT bin in the HBT analysis with 5000 events.

Alternative interpretations of grain-size data from Quaternary deposits

Abstract: Alternative interpretations of grain-size data from Quaternary deposits Several possibilities to present and to interpret the results of granulometric analyses of Quaternary fluvial, aeolian, glacial and wash-out slope deposits were investigated. Attention is paid particularly to the cumulative curves at a probability scale and the frequency curves, and it is shown how these curves can help to determine the sedimentary environment. The inclination of the cumulative curves in the part of the maximum proportion of a particular grain size appears significant. It appears possible to obtain information on the density and dynamics of the transporting medium from the course of the cumulative curves (inclination and spread of grain size). The examination of textural parameters allows to draw regression lines characteristic of both deposits from various sedimentary environments and deposits from one single environment but with different histories as to their transport dynamics.

The influence of chloride deicers on mineral nutrition and the health status of roadside trees in the city of Kielce, Poland

Abstract: Application of chemical road deicers has a negative impact on roadside vegetation. Every year, the trees in cities suffer from direct and indirect effects of salt application for winter road maintenance. To elucidate this problem in the city of Kielce, the chemistry of snow, soil, tree bark, and leaf samples has been investigated together with an assessment of the health status of the trees. Twelve investigation sites were selected along the roads with different traffic intensity. Snow samples were collected twice during the winter and analyzed for pH, EC, Na(+), Ca(2+), Mg(2+), and Cl(-). In soil (collected from two depth intervals), tree bark, and leaf samples, the concentrations of B, Ca, Fe, K, Mg, Mn, N, Na, P, S, and Zn were determined. The contents of total organic carbon (TOC) in soils, as well as the pH of soil and tree bark samples were also measured. Negative symptoms revealed by roadside trees included the loss of assimilative apparatus and decreased vitality. The results of chemical analyses indicated that the snowmelt might be a substantial source of chloride ions and alkalizing substances that influenced higher pH of soils. The soil samples displayed elevated concentrations of S and Zn and lower than typical for soil contents of B, Mg, and TOC. The pH of alkaline soils favored greater bioavailability of B and reduced bioavailability of Na and Zn by the trees examined.

Structure and serology of O-antigens as the basis for classification of Proteus strains

Abstract: This review is devoted to structural and serological characteristics of the O-antigens (O-polysaccharides) of the lipopolysaccharides of various Proteus species, which provide the basis for classifying Proteus strains to O-serogroups. The antigenic relationships of Proteus strains within and beyond the genus as well as their O-antigen-related bioactivities are also discussed.

Centrality dependence of proton and antiproton spectra in Pb +Pb collisions at 40A GeV and 158A GeV measured at the CERN Super Proton Synchrotron

Abstract: The yields of (anti)protons were measured by the NA49 Collaboration in centrality-selected Pb + Pb collisions at 40A and 158A GeV. Particle identification was obtained in the laboratory momentum range from 5 to 63 GeV/c by measuring the energy loss dE/dx in the time projection chamber detector gas. The corresponding rapidity coverage extends 1.6 units from midrapidity into the forward hemisphere. Transverse-mass spectra, the rapidity dependences of the average transverse mass, and rapidity density distributions were studied as a function of collision centrality. The values of the average transverse mass as well as the midrapidity yields of protons normalized to the number of wounded nucleons show only modest centrality dependences. In contrast, the shape of the rapidity distribution changes significantly with collision centrality, especially at 40A GeV. The experimental results are compared to calculations of the hadron-string dynamics and the ultrarelativistic quantum-molecular-dynamics transport models.

Theoretical Study of ElectronPhonon Relaxation in PbSe and CdSe Quantum Dots: Evidence for Phonon Memory

Abstract: Wehavecombinedanalyticaltheorywithabinitio nonadiabatic molecular dynamics to study the phonon-induced relaxation of photoexcited charge carriers in PbSe and CdSe semiconductorquantumdots(QDs).Densityfunctionaltheory calculations show dense distributions of electronic levels near the energy gap, attributed to the reconstruction and lack of absolute symmetry of the QD surface. Most of these states are optically dark, but they do couple to phonons and facilitate charge carrier relaxation. The time-domain simulations show a complex, nonexponential relaxation, in agreement with the observed non-Lorenzian spectral line shapes. The relaxation accelerates athigherphotoexcitationenergiesduetobothahigherdensityofcarrierstatesandalargernonadiabaticelectronphononcoupling. Overtime,carrier relaxation changes fromGaussian toexponential. TheGaussian componentislargerinsmallerdots;this maybea manifestation of the phonon bottleneck effect. Since Markovian rate models give exponential decay, we suggest that the more complex form of the carrier relaxation, observed in our simulations, can be attributed to phonon memory. The analytic theory developed within the framework of quantized Hamilton dynamics rationalizes this observation. It shows that a detailed description of the phonon modes is more important than a model for the electronic states.

Highly anisotropic and strongly dissipative hydrodynamics with transverse expansion

Abstract: A recently formulated framework of highly anisotropic and strongly dissipative hydrodynamics (ADHYDRO) is used to describe the evolution of matter created in ultra-relativistic heavy-ion collisions. New developments of the model contain: the inclusion of asymmetric transverse expansion (combined with the longitudinal boost-invariant flow) and comparisons of the model results with the RHIC data, which have become possible after coupling of ADHYDRO with THERMINATOR. Various soft-hadronic observables (the transverse-momentum spectra, the elliptic flow coefficient v 2, and the HBT radii) are calculated for different initial conditions characterized by the value of the initial pressure asymmetry. We find that as long as the initial energy density profile is unchanged the calculated observables remain practically the same. This result indicates the insensitivity of the analyzed observables to the initial anisotropy of pressure (provided the initial entropy density is changed to keep the initial energy density fixed) and suggests that the complete thermalization of the system may be delayed to easily acceptable times of about 1 fm/c.

Synthesizing lead antimonate in ancient and modern opaque glass

Abstract: Through the study of lead antimonate based opacifiers in three opaque glass productions—Egyptian glass of the 18th dynasty (1570–1292 BC), Roman mosaic tesserae and beads from Aquilea and Rome (2nd c. BC–5th c. AD) and Nevers lampworking glass figures 18th c. AD)—this paper shows the evolution of lead antimonate production during different periods of History. We also show the necessity of using systematic micro-chemical analyses, with both high spatial and high energy resolution techniques to investigate these types of materials. The synchrotron-based μ-XANES measurements combined with the microstructure observations (SEM and TEM), the chemical and structural analyses (EDX, WDS, μ-Raman), is the first step to getting information on the raw materials used and the technological processes employed to produce lead antimonate. The heterogeneity from one sample to another but also within the same sample, and even further within a single crystal aggregate clearly shows that a production cannot be unambiguously associated to a single chemical composition. However, differences between the three productions are clearly highlighted and hypotheses about glass manufacturing are proposed.

Non-boost-invariant motion of dissipative and highly anisotropic fluid

Abstract: The recently formulated framework of anisotropic and dissipative hydrodynamics (ADHYDRO) is used to describe non-boost-invariant motion of the fluid created at the early stages of heavy-ion collisions. Very strong initial asymmetries of pressure are reduced by the entropy production processes. By the appropriate choice of the form of the entropy source we can describe isotropization times of about 1 fm, which agrees with the common expectations that already at such times the perfect-fluid hydrodynamics may be applied. Our previous results are generalized by including the realistic equation of state as the limit of the isotropization processes.

Thermal stability, flammability and fire hazard of butadiene-acrylonitrile rubber nanocomposites

Abstract: This article presents the effect of the method of NBR cross linking on the thermal properties, flammability and fire hazard of its nanocomposites containing modified montmorillonite (NanoBent or Nanofil), using test results obtained by means of a derivatograph, oxygen index and cone calorimetry. It has been found that the thermal stability and flammability of the nanocomposites investigated depend on both the rubber network structure and the type of montmorillonite. The nanoadditives used reduce the flammability of cross-linked nitrile rubber and considerably limit its fire hazard.

K*(892)0 and K*(892)0 production in central Pb + Pb, Si + Si, C + C, and inelastic p + p collisions at 158A GeV

Abstract: Production of the K*(892)0 and K*(892)⁰ resonances was studied via their K⁺π⁻ and K⁻π⁺ decay modes in central Pb+Pb, Si+Si, C+C, and inelastic p+p collisions at 158A GeV(√(sNN)=17.3 GeV) with the NA49 detector at the CERN SPS. Transverse momentum and rapidity distributions were measured and total yields were estimated. The yield of K* exceeds that of K* by about a factor of two in nucleus-nucleus reactions. The total yield ratios ⟨K*⟩/⟨K+⟩ and ⟨K*⟩/⟨K-⟩ are strongly suppressed in central Pb+Pb compared to p+p, C+C, and Si+Si collisions, in agreement with the expected attenuation of these short-lived resonance states in the hadronic phase of the expanding fireball. The UrQMD model, although incorporating such a scenario, does not provide a quantitative description of the experimental results. The statistical hadron gas model assuming the same freeze-out parameters for stable hadrons and resonances overestimates the ⟨K*⟩/⟨K⟩ ratios in central Pb+Pb collisions by about a factor of 2.5.

CAM-related changes in chloroplastic metabolism of Mesembryanthemum crystallinum L.

Abstract: Crassulacean acid metabolism (CAM) is an intriguing metabolic strategy to maintain photosynthesis under conditions of closed stomata. A shift from C3 photosynthesis to CAM in Mesembryanthemum crystallinum plants was induced by high salinity (0.4 M NaCl). In CAM-performing plants, the quantum efficiencies of photosystem II and I were observed to undergo distinct diurnal fluctuations that were characterized by a strong decline at the onset of the day, midday recovery, and an evening drop. The temporal recovery of both photosystems’ efficiency at midday was associated with a more rapid induction of the electron transport rate at PSII. This recovery of the photosynthetic apparatus at midday was observed to be accompanied by extreme swelling of thylakoids. Despite these fluctuations, a persistent effect of CAM was the acceptor side limitation of PSI during the day, which was accompanied by a strongly decreased level of Rubisco protein. Diurnal changes in the efficiency of photosystems were parallel to corresponding changes in the levels of mRNAs for proteins of PSII and PSI reaction centers and for rbcL, reaching a maximum in CAM plants at midday. This might reflect a high demand for new protein synthesis at this time of the day. Hybridization of run-on transcripts with specific probes for plastid genes of M. crystallinum revealed that the changes in plastidic mRNA levels were regulated at the level of transcription.

Identity method to study chemical fluctuations in relativistic heavy-ion collisions

Abstract: Event-by-event fluctuations of the chemical composition of the hadronic final state of relativistic heavy-ion collisions carry valuable information on the properties of strongly interacting matter produced in the collisions. However, in experiments incomplete particle identification distorts the observed fluctuation signals. The effect is quantitatively studied and a new technique for measuring chemical fluctuations, the identity method, is proposed. The method fully eliminates the effect of incomplete particle identification. The application of the identity method to experimental data is explained.

Molecular conductors with a 8-hydroxy cobalt bis(dicarbollide) anion.

Abstract: Molecular conductors based on the 8-hydroxy cobalt bis(dicarbollide) anion, (TMTTF)[8-HO-3,3′-Co(1,2-C2B9H10)(1′,2′-C2B9H11)] (1), (BMDT-TTF)[8-HO-3,3′-Co(1,2-C2B9H10) (1′,2′-C2B9H11)] (2), and (BEDT-TTF)[8-HO-3,3′-Co(1,2-C2B9H10)(1′,2′-C2B9H11)] (3), were synthesized, and their crystal structures and electrical conductivities were determined. Compounds 2 and 3 are isostructural to the corresponding radical-cation salts of the parent cobalt bis(dicarbollide). All of the radical-cation salts prepared were found to be semiconductors. The relative stability of the rotation conformers of the [8-HO-3,3′-Co(1,2-C2B9H10)(1′,2′-C2B9H11)]− anion was estimated using DFT/BP86 quantum chemical calculations.

First Observation of Two-Electron One-Photon Transitions in Single-Photon K -Shell Double Ionization

Abstract: Experimental evidence for the correlated two-electron one-photon transitions ($1{s}^{\ensuremath{-}2}\ensuremath{\rightarrow}2{s}^{\ensuremath{-}1}2{p}^{\ensuremath{-}1}$) following single-photon $K$-shell double ionization is reported. The double $K$-shell vacancy states in solid Mg, Al, and Si were produced by means of monochromatized synchrotron radiation, and the two-electron one-photon radiative transitions were observed by using a wavelength dispersive spectrometer. The two-electron one-photon transition energies and the branching ratios of the radiative one-electron to two-electron transitions were determined and compared to available perturbation theory predictions and configuration interaction calculations.

Chromatographic methods and techniques used in studies of coals, their progenitors and coal-derived materials

Abstract: The use of chromatography in studies of coals, their progenitors and coal-related products was reviewed. The specificity of the coal structure was discussed. The use of extraction in preparing study samples was discussed paying special attention to the occurrence of undesirable phenomena such as aggregation of coal derivate molecules, resulting from the formation of their dimers and trimers, and degradation of polar solvents at temperatures above 350 °C. The following ways of fractionating samples of coal materials were considered: thermal, solvent, column with the use of preparative size exclusive chromatography and preparative thin layer chromatography as well as membrane separation. The use of chromatography coupled with experimental techniques such as mass spectrometry, infrared spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and pyrolysis was analysed.

On the chemical composition of cosmic rays of highest energy

Abstract: We present arguments aiming at reconciling apparently contradictory results concerning the chemical composition of cosmic rays (CRs) of highest energy, coming recently from the Auger and HiRes collaborations. In particular, we argue that the energy dependence of the mean value and root mean square fluctuation of shower maxima distributions observed by the Auger experiment are not necessarily caused by the change of the nuclear composition of primary CRs. They could also be caused by the change of distribution of the first interaction point in the cascade. A new observable, in which this influence is strongly suppressed, is proposed and tested.

Energy dependence of kaon-to-proton ratio fluctuations in central Pb+Pb collisions from √[sNN]=6.3 to 17.3 GeV

Abstract: Kaons and protons carry large parts of two conserved quantities: strangeness and baryon number. It is argued that their correlation and thus also fluctuations are sensitive to conditions prevailing at the anticipated parton-hadron phase boundary. Fluctuations of the (K++K-)/(p+p ) and K+/p ratios have been measured for the first time by NA49 in central Pb+Pb collisions at five CERN Super Proton Synchrotron energies between √sNN=6.3 and √sNN=17.3 GeV. Both ratios exhibit a change of sign in σdyn, a measure of nonstatistical fluctuations, around √sNN=8 GeV. Below this energy, σdyn is positive, indicating higher fluctuation compared to a mixed event background sample, while for higher energies, σdyn is negative, indicating correlated emission of kaons and protons. The results are compared to hadronic transport model calculations which fail to reproduce the energy dependence.

Generalized thermodynamic uncertainty relations

Abstract: We analyze an ensemble in which energy ( E ), temperature ( T ) and multiplicity ( N ) can all fluctuate and with the help of nonextensive statistics we propose a relation connecting all fluctuating variables. It generalizes Lindhard’s thermodynamic uncertainty relations known in literature.