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A triskelion‐shaped triradical triindeno[1,2‐a:1′,2′‐g : 1′′,2′′‐m]triphenylen‐7‐yl (1) and its internally fused derivative (2) obtained by oxidative cyclization were prepared in a straightforward synthetic sequence. Both compounds were confirmed to be triradicals and to possess intramolecular antiferromagnetic exchange interactions between spins, displaying a spin‐frustrated doublet ground state with doublet‐quartet energy gaps of −0.14 kcal/mol for 1 and −0.06 kcal/mol for 2. Despite their open‐shell character, they were sufficiently stable to be handled under ambient conditions on a timescale of days. Both compounds could be reversibly reduced to mono‐, di‐, and trianions and oxidized to 1+ and 22+, with strong NIR absorptions (1800 to over 3200 nm) observed for all open‐shell ions. [ABSTRACT FROM AUTHOR]

Copyright of KUL Journal of Legal Studies / Studia Prawnicze KUL is the property of John Paul II Catholic University of Lubin / Katolicki Uniwersytet Lubelski Jana Pawla II and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A family of propeller‐shaped donor‐acceptor hexapyrrolylbenzenes (HPBs) were designed and synthesized by sequential nucleophilic substitution of hexafluorobenzene with π‐extended pyrroles. In particular, four hybrids were obtained, containing various combinations of electron‐rich and electron‐poor acenaphthylene‐fused pyrroles. Additionally, to probe the efficiency of ortho transfer interactions, a system was designed containing unique donor and acceptor subunits spatially separated with four unfunctionalized pyrroles. DFT calculations showed propeller‐shaped geometries of all HPB molecules and separation of frontier molecular orbitals between donor and acceptor subunits. Steady‐state and time‐resolved photophysical measurements revealed charge‐transfer (CT) character of the emission with strong positive dependence on solvent polarity. The principal CT pathway involves ortho‐positioned pairs of donors and acceptors and requires bending of the acceptor in the excited state. [ABSTRACT FROM AUTHOR]

Geochemical studies of CO2-rich therapeutic waters in the Sudetes have provided new data on a wide range of trace elements, going beyond standard chemical analyses of such waters. A consistent set of physicochemical data obtained using the same analytical methods was subjected to statistical analyses, including hierarchical clustering, factor analysis and nonparametric tests (Kruskal-Wallis, Tau Kendall), to reveal geochemical relationships between physicochemical and chemical parameters in the waters, and their relationships with the aquifer lithology. Distinct differences in the composition of waters found in crystalline rocks (mainly gneisses and mica schists) and sedimentary rocks were identified. The wide range of elements can be associated with the hydrolysis of silicate minerals, including alkali and alkali earth metals (Li, Na, K, Rb, Cs, Be) and (mostly) transition elements (Fe, Mn, Zn, Co, W, Mg). Carbonate equilibria are the next important factor as it determines the aggressiveness of the water towards the minerals of aquifer rocks and affects the concentrations of numerous solutes. The probable common origin of chlorides, bromides and sulphates together with Li, Na, Sr may be related to the relict saline component of deep circulating waters, a hypothesis that requires further investigations. [ABSTRACT FROM AUTHOR]

Copyright of Dental Forum is the property of Dental Forum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

π‐Extended acenaphtho[1,2‐d][1,2,3]triazoles, the unsubstituted Anta‐H and its di‐tert‐butyl derivative Dibanta‐H, as well as 5,6,7,8‐tetrahydro‐1H‐naphtho[2,3‐d][1,2,3]triazole Cybta‐H were obtained in concise syntheses. In the solid state, Dibanta‐H forms an unprecedented hydrogen‐bonded cyclic tetrad, stabilized by dispersion interactions of the bulky tBu substituents, whereas a cyclic triad was found in the crystal structure of Anta‐H. These cyclic assemblies form infinite slipped stacks in the crystals. Evidence for analogous hydrogen‐bonded self‐assembly in solution was provided by low‐temperature NMR spectroscopy and computational analyses. Kuratowski‐type pentanuclear complexes [Zn5Cl4(Dibanta)6] and [Zn5Cl4(Cybta)6] were prepared from the respective triazoles. In the Dibanta complexes, the π‐aromatic surfaces of the ligands extend from the edges of the tetrahedral Zn5 core, yielding an enlarged structure with significant internal molecular free volume and red‐shifted fluorescence. [ABSTRACT FROM AUTHOR]

Risk management plays a vital role in various construction activities to maximise construction profitability and reduce the loss of construction projects. Managing risk in construction projects is considered the most significant process in achieving the objectives in terms of quality, cost and time. Also, it is necessary to prioritise and identify the most probable risk that occurs during construction projects. Due to the unanticipated risk, around 40% of construction projects are dropdown in developing countries. This paper aims to develop and identify the project delay risk at a minimum duration of time and cost. Our paper comprises of five major phases: Identification of risk source and its factors, Systemization and Preprocessing of the dataset, Analysis of dataset constraints, Sensitivity data computation, and Tool selection using DRNN-MSCA to determine the risk, thereby establishing an effective and accurate prediction analysis. Here, the machine learning algorithm, namely the Deep Recurrent Neural Network (DRNN) and the Modified Sine Cosine Optimization Algorithm (MSCA), is integrated to minimise the inter-dependence and the complexity of the construction delay. The 5-point Likert scale computes the probability and the variables impact by the measures from very low to a very high level. Finally, the performance of the proposed approach is calculated and compared with a few other existing approaches such as ANN (Artificial Neural Network), RF-GA (Random forest and Genetic algorithm) and ML (Machine learning). The results reveal that the proposed approach provides a superior accuracy performance is 81.65%, with less cost and time delay. [ABSTRACT FROM AUTHOR]

The World Health Organization defines Paget disease as intraepithelial cancer arising from eccrine and apocrine glands of the skin with two distinguishable types: mammary Paget disease (MPD) and EMPD, commonly located in the anogenital region (van der Linden et al. [16]). In Poland, vulvar cancer is the fourth most common malignant neoplasm of reproductive organs in women. However, other malignancies also occur including Bowen's disease (BD) and extramammary Paget disease (EMPD). Importance of immunohistochemical staining in differential diagnosis of extramammary Paget and Bowen's diseases located in female anogenital region - a case report. [Extracted from the article]