Luminescent Properties of (Ca7ZrAl6O18-Ca3Al2O6-CaZrO3):Eu3+ Composite Ceramics and Tracing in the Hydration Process.

In this work, solid-state reaction sintering was used to fabricate Ca7ZrAl6O18-Ca3Al2O6-CaZrO3:Eu3+ ternary composite ceramics and cements. The structural, microstructural, and spectroscopic properties of the ceramics with different Eu2O3 content were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), and spectrofluorimetry, respectively. The XRD patterns analyzed with Rietveld refinement confirm the presence of the orthorhombic phase of Ca7ZrAl6O18 and the cubic phase of Ca3Al2O6 in all the samples, indicating that doping of Eu3+ slightly changes the crystalline structure of both aluminate phosphors. EDS analysis revealed that the Eu doping element was strongly concentrated to the two phases, i.e., Ca7ZrAl6O18 and Ca3Al2O6, with the Eu concentrations of 8.45 wt.% and 8.26 wt.%, respectively. The luminescent properties of the ceramics doped with different Eu3+ ion concentrations were investigated by excitation and emission spectroscopy at room temperature. These results were compiled using a laser with an optical parametric oscillator (OPO) system. The obtained spectra indicated changes in the luminescence intensity and shape occurring with phase composition and Eu2O3 concentration. The emission spectra of the ceramics exhibit a strong dependence on the excitation wavelength in the range from 210 to 300 nm, and invariably, five peaks were assigned to the 5D0 → 7FJ (J = 0, 1, 2, 3, 4) transitions of Eu3+. The luminescence spectroscopy was then used to trace the early and long-term hydration behavior of cements. Thus, luminescence spectroscopy may provide a new tool for non-destructive testing of cement-based structures.

Structural and Optical Properties of Pure and Sulfur-Doped Silicate-Phosphate Glass.

A series of silicate-phosphate glass materials from the SiO2-P2O5-K2O-MgO system (pure and doped with sulfur ions) were synthesized by melting raw material mixtures that contained activated carbon as a reducer. The bulk composition of glass was confirmed with X-ray fluorescence spectroscopy. The homogeneity of the glass was confirmed through elemental mapping at the microstructural level with scanning electron microscopy combined with an analysis of the microregions with energy-dispersive X-ray spectroscopy. The structural and optical properties of the glass were studied by using spectroscopic techniques. The infrared spectroscopy studies that were conducted showed that the addition of sulfur caused changes in the silicate-phosphate networks, as they became more polymerized, which was likely related to the accumulation of potassium near the sulfur ions. By using irradiation with an optical parametric oscillator (OPO) nanosecond laser system operating at the second harmonic wavelength, the glass samples emitted a wide spectrum of luminescence, peaking at about 700 nm when excited by UV light (210-280 nm). The influence of the glass composition and the laser-processing parameters on the emission characteristics is presented and discussed. This work also referred to the density, molar volume, and theoretical optical basicity of pure and sulfur-doped glass.

Ecological amplitude and indication potential of mining bees (Andrena spp.): a case study from the post-agricultural area of the Kampinos National Park (Poland).

The mining bee (Andrena spp.) play a key role in ensuring plant and animal diversity. The present study examines their diversity in a post-agricultural landscape exemplified by the Kampinos National Park (KNP), a UNESCO Biosphere Reserve in Poland. The following hypotheses were addressed: (H1) the mining bees demonstrate a narrow ecological amplitude, (H2) there are no indicator species for particular habitats, and (H3) the studied mining bees have the same ecological preferences to those presented in the literature. A total of 40 catch per unit effort samples (CPUE) were collected across various habitats with different soil humidity. Forty-six species were recorded, representing 46% of mining bees and approximately 10% of the known Polish bee fauna. Nineteen of the recorded species (41%) were assigned to CR-NT threat categories, indicating that the national park plays a significant role in preserving mining bee species diversity and their conservation. None of the hypotheses (H1, H2, H3) were confirmed. The mining bees were found to demonstrate a wide ecological amplitude. Surprisingly, habitats located in dry and wet soils were both characterised by high abundance and species richness. Seventeen indicators were distinguished among the dominant and rarer species. Our findings suggest that Andrena nigroaenea and A. ventralis (lower humidity), as well as A. alfkenella and A. minutuloides (higher humidity), have different significant relationships with habitat soil humidity to those reported in the literature.

Vascular plants and mosses as bioindicators of variability of the coastal pine forest (Empetro nigri-Pinetum).

Empetro nigri-Pinetum is a unique sea coast plant community developing along the Baltic Sea from Germany to Lithuania. Our detailed field research of bryophytes and vascular plants has highlighted the regional diversity of the Empetro nigri-Pinetum typicum plant community throughout its range in Central Europe. Our study indicated that vascular plants and mosses effectively discriminate against the described phytocoenoses, thus it was possible to distinguish three variants of the coastal forest: Calluna-Deschampsia (from Germany), Vaccinium vitis-idaea (from Poland) and Melampyrum-Deschampsia (from Lithuania). Redundancy analysis indicated that the division is related to the habitat conditions of the analyzed areas, with humidity having the greatest impact on this differentiation. Kohonen's artificial neural network (i.e. self-organising map, SOM) confirmed the heterogeneous nature of the studied phytocenoses, and combined with the IndVal index enabled identification of indicator species for respective studied patches: Deschampsia flexuosa for Calluna-Deschampsia group; Aulacomnium palustre, Calluna vulgaris, Carex nigra, Dicranum polysetum, Erica tetralix, Oxycoccus palustris, Sphagnum capillifolium, Vaccinium uliginosum and Vaccinium vitis-idaea for Vaccinium vitis-idaea group; and young specimens of Betula pendula, Lycopodium annotinum, Melampyrum pratense and Orthilia secunda for Melampyrum-Deschampsia group. Thereby, our study showed that individual groups of species can be very good bioindicators for each of the studied phytocoenoses.

Temperature and E-Poling Evolution of Structural, Vibrational, Dielectric, and Ferroelectric Properties of Ba1-xSrxTiO3 Ceramics (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.45).

Lead-free Ba1-xSrxTiO3 (BST) (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.45) ceramics were successfully prepared via the solid-state reaction route. A pure perovskite crystalline structure was identified for all compositions by X-ray diffraction analysis. The basic phase transition temperatures in these ceramics were studied over a wide temperature range. A change in symmetry from a tetragonal to cubic phase was detected, which was further proven by phonon anomalies in composition/temperature-dependent Raman spectra. The incorporation of Sr2+ into BaTiO3 (BT) lead to a shift in the phase transitions to lower temperatures, suppressing the ferroelectric properties and inducing relaxor-like behavior. Therefore, it was reasonable to suppose that the materials progressively lack long-range ordering. The initial second-harmonic generation (SHG) measurements demonstrated that the cubic phase of BST ceramics is not purely centrosymmetric over a wide temperature interval. We discussed the possible origin of the observed effects, and showed that electric field poling seems to reconstruct the structural ordering destroyed by the introduction of Sr2+ to BT. In the first approximation, substitution of Sr for larger Ba simply reduced the space for the off-central shift in Ti in the lattice and hence the domain polarization. A-site cation ordering in BST and its influence on the density of electronic states were also explored. The effect of doping with strontium ions in the BST compound on the density of electronic states was investigated using ab initio methods. As the calculations showed, doping BT with Sr2+ atoms led to an increase in the bandgap. The proposed calculations will also be used in the subsequent search for materials optimal for applications in photovoltaics.

Preparation, Characterization and Magneto-Optical Properties of Sm-Doped Y2O3 Polycrystalline Material.

In this paper, physicochemical properties of pure Y2O3 and samarium (Sm)-doped Y2O3 transparent ceramics obtained via arc plasma melting are presented. Yttria powder with a selected molar fraction of Sm was first synthesized by a solid-state reaction method. High transparent yttria ceramics were obtained by arc plasma melting from both the pure and Sm oxide-doped powders. The morphological, chemical and physical properties were investigated by X-ray diffraction and scanning electron microscopy. The optical band gap was calculated from the absorption spectra so as to understand the electronic band structure of the studied materials. Samples indicate a series of luminescence bands in the visible region after excitation by laser light in the range from 210 to 250 nm. Magneto-optical measurements were carried out in the 300-800 nm range at room temperature. It can be seen that a maximum Verdet constant ca. 24.81 deg/T cm was observed for 405 nm and this value decreases with increasing wavelength. The potential usefulness of the polycrystalline material dedicated to optics devices is presented.

The spatial and temporal reconstruction of a medieval moat ecosystem.

Moats and other historical water features had great importance for past societies. The functioning of these ecosystems can now only be retrieved through palaeoecological studies. Here we aimed to reconstruct the history of a stronghold's moat during its period of operation. Our spatio-temporal approach allowed mapping of the habitat changes within a medieval moat for the first time. Using data from four cores of organic deposits taken within the moat system, we describe ecological states of the moat based on subfossil Chironomidae and Ceratopogonidae assemblages. We found that over half (57%) of the identified dipteran taxa were indicative of one of the following ecological states: limnetic conditions with or without periodic water inflow, or marshy conditions. Samples representing conditions unfavourable for aquatic insects were grouped in a separate cluster. Analyses revealed that the spatio-temporal distribution of midge assemblages depended mostly on depth differences and freshwater supply from an artificial channel. Paludification and terrestrialization did not happen simultaneously across the moat system, being greatly influenced by human activity. The results presented here demonstrate the importance of a multi-aspect approach in environmental archaeology, focusing not only on the human environment, but also on the complex ecology of the past ecosystems.

Fires, vegetation, and human-The history of critical transitions during the last 1000 years in Northeastern Mongolia.

Fires are natural phenomena that impact human behaviors, vegetation, and landscape functions. However, the long-term history of fire, especially in the permafrost marginal zone of Central Asia (Mongolia), is poorly understood. This paper presents the results of radiocarbon and short-lived radionuclides (210Pb and 137Cs) dating, pollen, geochemical, charcoal, and statistical analyses (Kohonen's artificial neural network) of sediment core obtained from Northern Mongolia (the Khentii Mountains region). Therefore, we present the first high-resolution fire history from Northern Mongolia covering the last 1000 years, based on a multiproxy analysis of peat archive data. The results revealed that most of the fires in the region were likely initiated by natural factors, which were probably related to heatwaves causing prolonged droughts. We have demonstrated the link between enhanced fires and "dzud", a local climatic phenomenon. The number of livestock, which has been increasing for several decades, and the observed climatic changes are superimposed to cause "dzud", a deadly combination of droughts and snowy winter, which affects fire intensity. We observed that the study area has a sensitive ecosystem that reacts quickly to climate change. In terms of changes in the vegetation, the reconstruction reflected climate variations during the last millennium, the degradation of permafrost and occurrence of fires. However, more sites with good chronologies are needed to thoroughly understand the spatial relationships between changing climate, permafrost degradation, and vegetation change, which ultimately affect the nomadic societies in the region of Central and Northern Mongolia.

Advancing improvement in riverine water quality caused a non-native fish species invasion and native fish fauna recovery.

The knowledge of biotic and abiotic drivers that put non-native invasive fishes at a disadvantage to native ones is necessary for suppressing invasions, but the knowledge is scarce, particularly when abiotic changes are fast. In this study, we increased this knowledge by an analysis of the biomass of most harmful Prussian carp Carassius gibelio in a river reviving from biological degradation. The species' invasion followed by the invasion's reversal occurred over only two decades and were documented by frequent monitoring of fish biomass and water quality. An initial moderate improvement in water quality was an environmental filter that enabled Prussian carp's invasion but prevented the expansion of other species. A later substantial improvement stimulated native species' colonization of the river, and made one rheophil, ide Leuciscus idus, a significant Prussian carp's replacer. The redundancy analysis (RDA) of the dependence of changes in the biomass of fish species on water quality factors indicated that Prussian carp and ide responded in a significantly opposite way to changes in water quality in the river over the study period. However, the dependence of Prussian carp biomass on ide biomass, as indicated by regression analysis and analysis of species traits, suggests that the ecomorphological similarity of both species might have produced interference competition that contributed to Prussian carp's decline.

Structural and Magneto-Optical Characterization of La, Nd: Y2O3 Powders Obtained via a Modified EDTA Sol-Gel Process and HIP-Treated Ceramics.

In this study, pure Y2O3, La0.1Y1.9O3 and La0.1Nd0.12Y1.78O3 nanosized powders were successfully synthesized by a modified sol-gel method. Pure and rare-earth ions doped yttria powders were characterized by X-ray diffraction, scanning electron microscopy and Brunauer-Emmett-Teller methods. The powders were sintered by the hot isostatic pressing process. The highest in-line transmittance of 56% was obtained at 800 nm and increased in the IR region. The influence of the lanthanum and neodymium ions on the physicochemical properties of yttria were discussed. The La-Nd-doped material exhibited a Verdet constant over 4000 deg/T·m at 400 nm and low thermal dependence. An interesting evolution of the Verdet constant across the absorption band with high resolution was studied. A study of the optical and magneto-optical properties of yttria doped with Nd3+ and La3+ is discussed in this paper.

Local habitat conditions shaping the assemblages of vespid wasps (Hymenoptera: Vespidae) in a post-agricultural landscape of the Kampinos National Park in Poland.

The landscape of the Kampinos National Park (KPN), a UNESCO Biosphere Reserve in Poland, is a mosaic of habitats created by natural processes and human activities. However, ongoing abandonment of traditional management has led to the development of forest communities in formerly open areas. The aim of the study was to identify the local habitat conditions promoting the abundance and diversity of wasp species (Vespidae) in the post-agricultural landscape of KPN. A total of 52 samples of Vespidae caught per unit effort (CPUE) were collected across various habitats with different levels of soil humidity, bare ground and mosaicity. The highest numbers and greatest species richness of vespids were recorded in open habitats on semihydrogenic and dry soil, which provided nesting sites for hypergeic (nesting above the ground) and endogeic (ground nesting) wasps. Many solitary species that are hypergeic were significantly associated with old, abandoned wooden buildings. As vespids need resources to build and provision the nest, their communities were shaped not only by the nature of the habitat sampled but also by the mosaicity of the surrounding area. The highest abundance and species richness were recorded in samples from a heterogenous landscape, which provided a wider range of available resources in the vicinity of the nest. Our findings have significant implications for the management of park landscapes: afforestation of open habitats, both human-induced and resulting from natural succession, and the removal of old abandoned wooden buildings may limit landscape mosaicity and thus decrease hymenopteran diversity.

Optical Magnetometry Based on Nanodiamonds with Nitrogen-Vacancy Color Centers.

Nitrogen-vacancy color centers in diamond are a very promising medium for many sensing applications such as magnetometry and thermometry. In this work, we study nanodiamonds deposited from a suspension onto glass substrates. Fluorescence and optically detected magnetic resonance spectra recorded with the dried-out nanodiamond ensembles are presented and a suitable scheme for tracking the magnetic-field value using a continuous poly-crystalline spectrum is introduced. Lastly, we demonstrate a remote-sensing capability of the high-numerical-aperture imaging fiber bundle with nanodiamonds deposited on its end facet.

[Exemplary classification of otolaryngologic data using the Kohonen artificial neural network]. / Przykladowe zastosowanie sztucznej sieci neuronowej kohonena w otolaryngoloii.

An exemplary classification of otolaryngological data with use of the Kohonen artificial neural network is presented along with an evaluation of grouping effectiveness. The study was based on 220 patients with otosclerosis, including 184 women and 36 men, aged 16-68, operated at the Otosurgery Department, Medical University of Lodz in 1984-1992. The neural network distinguished 3 clusters considerably differing in air and bone conduction preoperatively and as a result in the values of postoperative air-bone gap. The effectiveness of classification was also exhibited in congruent with previous knowledge differences between clusters in many other variables not presented to the neural network.

Long-Term Patterns in the Population Dynamics of Daphnia longispina, Leptodora kindtii and Cyanobacteria in a Shallow Reservoir: A Self-Organising Map (SOM) Approach.

The recognition of long-term patterns in the seasonal dynamics of Daphnia longispina, Leptodora kindtii and cyanobacteria is dependent upon their interactions, the water temperature and the hydrological conditions, which were all investigated between 1999 and 2008 in the lowland Sulejow Reservoir. The biomass of cyanobacteria, densities of D. longispina and L. kindtii, concentration of chlorophyll a and water temperature were assessed weekly from April to October at three sampling stations along the longitudinal reservoir axis. The retention time was calculated using data on the actual water inflow and reservoir volume. A self-organising map (SOM) was used due to high interannual variability in the studied parameters and their often non-linear relationships. Classification of the SOM output neurons into three clusters that grouped the sampling terms with similar biotic states allowed identification of the crucial abiotic factors responsible for the seasonal sequence of events: cluster CL-ExSp (extreme/spring) corresponded to hydrologically unstable cold periods (mostly spring) with extreme values and highly variable abiotic factors, which made abiotic control of the biota dominant; cluster CL-StSm (stable/summer) was associated with ordinary late spring and summer and was characterised by stable non-extreme abiotic conditions, which made biotic interactions more important; and the cluster CL-ExSm (extreme/summer), was associated with late spring/summer and characterised by thermal or hydrological extremes, which weakened the role of biotic factors. The significance of the differences between the SOM sub-clusters was verified by Kruskal-Wallis and post-hoc Dunn tests. The importance of the temperature and hydrological regimes as the key plankton-regulating factors in the dam reservoir, as shown by the SOM, was confirmed by the results of canonical correlation analyses (CCA) of each cluster. The demonstrated significance of hydrology in seasonal plankton dynamics complements the widely accepted pattern proposed by the plankton succession model for lakes, the PEG (Plankton Ecology Group), and may be useful for the formulation of management decisions in dam reservoirs.

Molecular subtyping of bladder cancer using Kohonen self-organizing maps.

Kohonen self-organizing maps (SOMs) are unsupervised Artificial Neural Networks (ANNs) that are good for low-density data visualization. They easily deal with complex and nonlinear relationships between variables. We evaluated molecular events that characterize high- and low-grade BC pathways in the tumors from 104 patients. We compared the ability of statistical clustering with a SOM to stratify tumors according to the risk of progression to more advanced disease. In univariable analysis, tumor stage (log rank P = 0.006) and grade (P < 0.001), HPV DNA (P < 0.004), Chromosome 9 loss (P = 0.04) and the A148T polymorphism (rs 3731249) in CDKN2A (P = 0.02) were associated with progression. Multivariable analysis of these parameters identified that tumor grade (Cox regression, P = 0.001, OR.2.9 (95% CI 1.6-5.2)) and the presence of HPV DNA (P = 0.017, OR 3.8 (95% CI 1.3-11.4)) were the only independent predictors of progression. Unsupervised hierarchical clustering grouped the tumors into discreet branches but did not stratify according to progression free survival (log rank P = 0.39). These genetic variables were presented to SOM input neurons. SOMs are suitable for complex data integration, allow easy visualization of outcomes, and may stratify BC progression more robustly than hierarchical clustering.

Factors shaping communities of pyrophilous macrofungi in microhabitats destroyed by illegal campfires.

Pyrophilous macrofungi (PM) are a narrowly specialised group appearing exclusively in plant communities recently destroyed by fire. Their significance has hitherto been studied only for vegetation destroyed over large areas, while in small areas of fire, i.e., microhabitats they are viewed as independent components of the community linked only to the substratum. In the present work, the following hypotheses were tested: (1) species structures of PM in microhabitats depend on the type of plant community, (2) PM form communities on a small scale which are similar in structure and function to analogous large scale communities. We studied 20 surfaces destroyed by illegal campfires in four natural plant communities: oak-hornbeam forest Tilio-Carpinetum (TC), lowland acidophilus beech forest Luzulo pilosae-Fagetum (LF), suboceanic pine forest Leucobryo-Pinetum (LP), and an initial-phase xerothermic grassland community on a transitional habitat (MH). TC and LF habitats were conspicuously more favourable for PM than LP and MH. In TC and LF fire leads to significant loss of mycorrhizae in the upper layer of leaf litter. This provides a development opportunity for ectomycorrhizal PM species which, having little competition, substitute for the destroyed fragments of mycorrhizal networks. In LP and MH fire over a small surface does not destroy more deeply located mycorrhizal associations. Another important factor for PM influencing the quality of environment is the fertility of soil: highest in TC, intermediate in LF and lowest in LP and MH. The results casts doubt on the concept that PM are only synusia linked to the substratum (burnt wood). PM growing in microhabitats constitute an important group of organisms which facilitate rapid regeneration of plant community fragments destroyed by fire.

Significance of CDKN2A gene A148T variant in patients with bladder cancer.

OBJECTIVES: The A148T polymorphism of CDKN2A gene is observed in various neoplasms with the incidence rate of 3-35%, however, rather little is known either about the frequency of its occurrence or of its significance in urinary bladder carcinoma. MATERIALS AND METHODS: DNA was isolated from blood of 156 patients with urinary bladder carcinoma (130 men). In histopathology, 84 cases were classified as G1, 42 as G2, and 30 as G3. The clinical stage was in 81 cases estimated at Ta and in 75 cases at T1-T4. A148T polymorphism was detected by the MSSCP technique and by sequencing. RESULTS: A148T polymorphism was identified in 9/156 urinary bladder carcinoma cases (only in men). The obtained results were compared with the polymorphism incidence for the Polish population, estimated by Debniak et al. The occurrence in the group of the bladder cancer patients turned out higher (5.77%) from that in the control group (2.89%) (G test, table 2×2: NBLADDER CANCER = 156, NCONTROL = 1210, G = 4.298, p <0.05). CONCLUSION: Summing up and taking into account the analysis of clinical parameters and the age of the disease occurrence, the A148T polymorphism of CDKN2A gene was identified in the study group only in men, in whom the disease was diagnosed above the age of 60, while the diagnosed neoplasms were in the majority of cases characterized by higher clinical stages and higher grades of malignancy. This has been the first study that attempted to show a potential association between A148T alterations and an increased risk for bladder cancer development.