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The occurrence of subsurface karst caves can cause the development of superficial depressions which, in turn, may pose a construction hazard. Identifying such a substratum requires integrated non-invasive measurement methods. The main objective of the study was to demonstrate the effectiveness of the non-invasive ERT, TLS, and GPR survey techniques in identifying the karst floor and determining the direction of discontinuities around the cave. The paper analyzes the limitations of the methods used in the study of heterogeneous media. These limitations are related to the methodology and measurement conditions, data processing, and interpretation in the context of the resolution and depth range. The study was conducted using the example of the Jaskinia pod Świecami cave, formed in the Sarmatianal calcarenites in Poland. The research confirmed its complex karst-anthropogenic genesis. The cave was formed as a result of the infiltration of rainwater and the dissolution of limestone by groundwater, while the paleokarst forms that are characteristic of it and of the surrounding caves and occur in their vicinity, i.e., narrow ridges called "karst candles", were formed as a result of water circulation during the local permafrost degradation in the middle Pleistocene. However, these forms were modified in the Upper Pleistocene and Holocene, as indicated by ERT images. [ABSTRACT FROM AUTHOR]

The definition of geoheritage recognizes scientific features that allow us to understand the history of the Earth and the processes forming and changing it. Some definitions also include intrinsic values as well as aesthetic and cultural importance of the geosites. Nevertheless, there is still a crucial aspect of human-geoscience (human-Earth) interrelations not clearly expressed in these definitions, which can justify the promotion of geoheritage and geoconservation, namely, the importance of the Earth, its structures, and processes in the development of human civilization and the importance of geosciences in the interpretation of human history and the present-day situation. In this paper, several examples of such geosites and categories of geosites are given: geological structures that conditioned human history, caves as a birthplace of human culture, springs as symbolic and real sources of water necessary for life and economy, mass movements as both destructive and constructive phenomena, and exploitation of mineral resources as a factor that has boosted the progress of civilization. Consequently, we postulate the inclusion in the meaning (definition) of geoheritage, sites, and categories of sites, that convince public and policy makers, that Earth’s elements and processes are ecosystem services of crucial importance. They are important not only for geoscientists, but in the development of human civilization, history, and the present state of human affairs. [ABSTRACT FROM AUTHOR]

Enthalpies and free energies of reaction for small neutral and charged beryllium deuterides BeD, BeD, and BeD that have been calculated are reported for a temperature range of 0 K to 1000 K. We discuss probable dissociation channels and possible ways of producing BeD by localizing the relevant transition states and by calculating corresponding rate constants. BeD and BeD are found to be the most stable ones among the considered compounds. BeD and $$ {\mathrm{BeD}}_2^{+} $$ are more likely to decompose into Be + D than into BeD + D. The metastable BeD and $$ {\mathrm{BeD}}_3^{+} $$ predominantly decompose into BeD + D. In light of our results on the reaction energetics, we can interpret the pathways for production of BeD via BeD and BeD intermediates observed in molecular dynamics simulations. [ABSTRACT FROM AUTHOR]

The aim of this study is to test the Campbell paradigm (Kaiser et al. 2010) as a novel theoretical framework for the measurement of concern about global climate change and to compare this measurement approach with conventional assessment of GCC concern which is based exclusively on evaluative rating of global climate change concern. Using survey data from 28 European countries ( N = 27,919), we find that GCC concern can be inferred not just from evaluative statements related to GCC, as is done in conventional measures, but also from other types of attitude-relevant responses (such as self-reports of mitigation activities and evaluation of mitigation policies). In addition, we also find that even though Campbellian measure is related in a theoretically expected way to conventional evaluative scale of GCC concern, and both measures assess the same latent construct, the former measure can predict difficult mitigation activity whereas the evaluative scale fails in this test of criterion validity. The poor performance of the conventional evaluative measure of GCC concern is due to the relative easiness of evaluative items that makes this measure insensitive to higher levels of GCC concern. [ABSTRACT FROM AUTHOR]

Aptamers are ligand-binding nucleic acids with affinities and selectivities that make them useful for the detection of a variety of compounds, including ochratoxin A. Theoretical methods can be applied to study the recognition interaction between aptamers and the ochratoxin A molecule. In this work, molecular dynamics simulations and quantum chemical calculations performed at the DFT level of theory were used to study the structures and energies of aptamers and aptamer-ochratoxin A complexes. The optimal structures as well as the interaction energies of these structures were elucidated. Divalent cations in the water solvent were shown to be an important influence on the structures and stabilities of the complexes. [ABSTRACT FROM AUTHOR]

We report calculated electron impact ionization cross sections (EICSs) for beryllium (Be) and some of its hydrides from the ionization threshold to 1 keV using the Deutsch-Märk (DM) and the Binary-Encounter-Bethe (BEB) formalisms. The positions of the maxima of the DM and BEB cross sections are very close in each case while the DM cross section values at the maxima are consistently higher. Our calculations for Be are in qualitative agreement with results from earlier calculations (convergent close-coupling, R matrix, distorted-wave and plane-wave Born approximation) in the low energy region. For the various beryllium hydrides, we know of no other available data. The maximum cross section values for the various compounds range from 4.0 × 10 to 9.4 × 10 cm at energies of 44 to 56 eV for the DM cross sections and 3.0 × 10 to 5.4 × 10 cm at energies of 40.5 to 60 eV for the BEB cross sections. [ABSTRACT FROM AUTHOR]

There are 13 sites subjected to the World Heritage Convention in Poland. Polish properties placed on the World Heritage (WH) List, up till now, were classified as cultural sites (C category) except for the Białowieża Forest (N category). In this paper, Polish properties of the WH are submitted to a comprehensive analysis in order to recognize their specific and significant geo(morpho)logical values. The Council of Europe and UNESCO recommend this procedure. Among Polish sites of WH, four have been favored as characterized by their special abiotic values: Cracow's Historic Centre, Wieliczka Salt Mine, Kalwaria Zebrzydowska, and Muskauer Park/Park Mużakowski. The abiotic features of these sites substantially contribute to the creation and development of their historical and cultural values and, in two cases (Wieliczka, Muskauer Park/Park Mużakowski), are important enough for reconsideration of the criteria of valorization for the WH List. The abiotic elements should be regarded as features developing their categorization towards natural criteria. [ABSTRACT FROM AUTHOR]

Nature has used a 'library approach' to constructing ligands for specific receptors and enzymes by combining a limited functional diversity of 20 amino acid side chains with a small array of secondary structure motifs - reverse turns, α-helices and β-strands. The dissection of multidomain proteins into small synthetic conformationally restricted components is an important step in the design of low-molecular-weight nonpeptides that mimic the activity of the native protein. Mimetics of critical functional domains might possess beneficial properties with regard to specificity and therapeutic potential compared to the intact proteinaceous species. Combinatorial secondary-structure-templated libraries provide a powerful engine for the development of novel vaccines and pharmaceuticals. [ABSTRACT FROM AUTHOR]

We present a theoretical study of accumulation of clusters consisting of up to 100 tungsten atoms based on information extracted from molecular dynamics trajectory simulations. The description is based on the rates corresponding to the single W atom attachment to Wn clusters and their dissociation processes. The results display a strong Arrhenius dependence of the dissociation rate constant on temperature. The preferred products of dissociation of the clusters composed of more than ten atoms are single W atoms and fragments with six to nine atoms. On the other hand, the association rate constants depend weakly on temperature. The obtained rate constants are used to calculate the chemical equilibrium of the W clusters that results in significant traces of small clusters only at high initial W atoms concentrations. [ABSTRACT FROM AUTHOR]

Human T-cell leukemia virus type 1 (HTLV-1) proteinase, a 125 residue polypeptide, was chemically synthesized using the solid phase method. The crude product was purified, renaturated and proteolytic activity was tested using oligopeptide substrates derived from processing sites of various retroviral polyproteins. Cleavage of the oligopeptide substrates together with an initial study using a series of HIV-1 and MAV (myeloblastosis associated virus) proteinase inhibitors suggest that the substrate specificity of HTLV-1 proteinase is very close to the of BLV (bovine leukemia virus) proteinase and distinct from that of both HIV-1 and MAV proteinases. [ABSTRACT FROM AUTHOR]

An abstract of the article "Prague's Spring of Lost Illusions," by Jan Urban is presented.