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A special characteristic of the present analysis is the calculation of the second moments of the excited-state orbitals. Because we find that the CASPT2 densities agree well with the CASSCF ones and since the MC-PDFT methods gets accurate excitation energies based on the CASSCF densities, we believe that we can trust these moments as far as giving a more accurate picture of the diffuseness of the excited-state orbitals in these prototype molecules than has previously been available.A methodology is presented for the determination of four pyrethroid (PYR) preservatives in wooden food contact materials (FCMs) using direct analysis in real time (DART) coupled with quadrupole-Orbitrap high-resolution mass spectrometry (Q-Orbitrap HRMS). The sampling mode and critical parameters of the DART-Q-Orbitrap HRMS protocol were systematically investigated. Good linearity was achieved for the four analytes with correlation coefficients all greater than 0.99. The limits of detection (LODs) and limits of quantitation (LOQs) of the method were in the range of 0.04-0.20 mg kg-1 and 0.10-0.50 mg kg-1, respectively. The mean recoveries ranged from 72.1% to 82.7% with relative standard deviations (RSDs) from 5.2% to 11.8% at three spiked levels. The developed method was proved to be suitable for rapid screening of PYRs in complex wooden FCM samples to ensure product safety and consumer health.BACKGROUND Osteoarthritis is a joint disorder characterized by articular cartilage degradation leading to joint stiffness and pain. The present study investigated the effect of hydroxypyridinone-coumarin on proliferation of chondrocytes. MATERIAL AND METHODS Chondrocyte proliferation was assessed by MTT assay, and distribution of cells in various phases of the cell cycle was determined using flow cytometry. RT-PCR and Western blot assays were used for assessment of mRNA and protein levels, respectively. Osteoarthritis was induced in the rats by injecting monosodium iodoacetate (5 mg/kg) by the intra-articular route. The rats in the treatment groups were intraperitoneally injected with 5, 10, or 15 mg/kg doses of hydroxypyridinone-coumarin alternately for 1 month. RESULTS The proliferation of chondrocytes was increased significantly (P less then 0.05) by treatment with hydroxypyridinone-coumarin in a concentration-based manner. The increase in chondrocyte proliferation by hydroxypyridinone-coumarin was maximum at 50 µM. Treatment with hydroxypyridinone-coumarin markedly increased chondrocyte population in S and G2/M phases, with subsequent reduction in G0/G1 phase. The cyclin D1, CDK4, and CDK6 levels in the chondrocytes were increased by treatment with hydroxypyridinone-coumarin. The production of IL-6, TNF-alpha, and IL-1ß in the osteoarthritis rats was markedly suppressed by hydroxypyridinone-coumarin. Treatment of the OA rats with hydroxypyridinone-coumarin markedly reduced the expression of IkappaB-alpha and NF-kappaB p65. CONCLUSIONS The present study revealed that the proliferative potential of chondrocytes is increased by hydroxypyridinone-coumarin through acceleration of G1/S transition. Moreover, hydroxypyridinone-coumarin treatment reduced inflammatory cytokine production in the osteoarthritis rats. Therefore, hydroxypyridinone-coumarin should be evaluated further for possible use in the treatment of osteoarthritis.BACKGROUND To reduce the burden of ST-segment elevation myocardial infarction (STEMI) in Poland the State Emergency Medical Services Management Support System (SEMS MSS), a unique teleinformatic system coordinating SEMS, was developed. According to the European Society of Cardiology (ESC) recommendations, medical emergency teams (METs) should diagnose STEMI using electrocardiogram (ECG) teletransmission and apply dual antiplatelet therapy (DAPT) as the initial treatment. AIM The aim of this work was to analyze MET interventions in patients with STEMI from January 1, 2018, to December 31, 2018, in Poland. METHODS MET interventions in Poland classified as I 21 (acute myocardial infarction) from January 1, 2018, to December 31, 2018, were analyzed retrospectively using emergency medical operation cards. RESULTS METs conducted 16 807 interventions classified as I 21 in 2018, which represented 0.5% of all MET interventions in this period in Poland. The most interventions were conducted in mazowieckie voivodeship (13.4%, P less then 0.001) and the fewest were conducted in podlaskie voivodeship (2.5%). 12-lead ECG was performed during 98.6% of interventions and ECG teletransmission was performed in 37.49% of interventions most often in mazowieckie (59.62%, P less then 0.001) and least often in lubelskie (13.8%). DAPT was applied during 72.12% of interventions in 49.68% of interventions, the purinergic signaling receptor Y12 (P2Y12) inhibitor used was clopidogrel and in 25.14% of interventions ticagrelor was used (P less then 0.001). A P2Y12 inhibitor was most often used in wielkopolskie (98.4%) and least often used in śląskie (40.34%). CONCLUSIONS Significant differences in the implementation of ESC recommendations regarding teletransmission and DAPT therapy were observed between particular voivodeships in Poland.The report of the Executive Committee for 2018 is presented.Further corrigenda and addenda for the article by Grimmer [Acta Cryst. (2017), A73, 333-345] are reported. New figures in the supporting information show how the restrictions on the forms of galvanomagnetic and thermomagnetic tensors are related to those on corresponding thermoelectromagnetic tensors.An inconsistent approximation in Wuttke [Acta Cryst. (2014), A70, 429-440] is corrected. Section 3.5 on the polar angle random walk is withdrawn.X-ray emission under electron-channelling conditions is used to distinguish between a non-centrosymmetric half-Heusler and a centrosymmetric full-Heusler crystal. For TiCo1.5+xSn the space-group determination based on a Rietveld refinement procedure became challenging for increasing Co content (x > 0.2), while electron channelling proved successful for higher Co content (x = 0.35). This technique can be used on crystals as small as (10 nm)3. open access.All the real combinations of cubes and octahedra (77657 in total) are enumerated and characterized by facet symbols and symmetry point groups. The most symmetrical polyhedra (with automorphism group orders not less than 6, 163 in total) are shown. It is assumed that they represent the most probable forms of natural diamond crystals. The results are discussed with respect to the Curie dissymmetry principle.Chemical nomenclature is perceived to be a closed topic. However, this work shows that the identification of polyanionic groups is still ambiguous and so is the nomenclature for some ternary compounds. Two examples, boron phosphate (BPO4) and boron arsenate (BAsO4), which were assigned to the large phosphate and arsenate families, respectively, nearly a century ago, are explored. The analyses show that these two compounds should be renamed phosphorus borate (PBO4) and arsenic borate (AsBO4). Beyond epistemology, this has pleasing consequences at several levels for the predictive character of chemistry. It paves the way for future work on the possible syntheses of SbBO4 and BiBO4, and it also renders previous structure field maps completely predictive, allowing us to foresee the structure and phase transitions of NbBO4 and TaBO4. Overall, this work demonstrates that quantum mechanics calculations can contribute to the improvement of current chemical nomenclature. Such revisitation is necessary to classify compounds and understand their properties, leading to the main final aim of a chemist predicting new compounds, their structures and their transformations.In this study, the atomic structure of the ternary icosahedral ZnMgTm quasicrystal (QC) is investigated by means of single-crystal X-ray diffraction. The structure is found to be a member of the Bergman QC family, frequently found in Zn-Mg-rare-earth systems. The ab initio structure solution was obtained by the use of the Superflip software. The infinite structure model was founded on the atomic decoration of two golden rhombohedra, with an edge length of 21.7 Å, constituting the Ammann-Kramer-Neri tiling. The refined structure converged well with the experimental diffraction diagram, with the crystallographic R factor equal to 9.8%. The Bergman clusters were found to be bonded by four possible linkages. Only two linkages, b and c, are detected in approximant crystals and are employed to model the icosahedral QCs in the cluster approach known for the CdYb Tsai-type QC. Additional short b and a linkages are found in this study. Short interatomic distances are not generated by those linkages due to the systematic absence of atoms and the formation of split atomic positions. The presence of four linkages allows the structure to be pictured as a complete covering by rhombic triacontahedral clusters and consequently there is no need to define the interstitial part of the structure (i.e. that outside the cluster). The 6D embedding of the solved structure is discussed for the final verification of the model. open access.Modern methods of quantum crystallography are techniques firmly rooted in quantum chemistry and, as in many quantum chemical strategies, electron densities are expressed as two-centre expansions that involve basis functions centred on atomic nuclei. Therefore, the computation of the necessary structure factors requires the evaluation of Fourier transform integrals of basis function products. Since these functions are usually Cartesian Gaussians, in this communication it is shown that the Fourier integrals can be efficiently calculated by exploiting an extension of the Obara-Saika recurrence formulas, which are successfully used by quantum chemists in the computation of molecular integrals. Implementation and future perspectives of the technique are also discussed.The theoretical framework and a joint quasi-Newton-Levenberg-Marquardt-simulated annealing (qNLMSA) algorithm are established to treat an inverse X-ray diffraction tomography (XRDT) problem for recovering the 3D displacement field function fCtpd(r – r0) = h · u(r – r0) due to a Coulomb-type point defect (Ctpd) located at a point r0 within a crystal [h is the diffraction vector and u(r – r0) is the displacement vector]. find more The joint qNLMSA algorithm operates in a special sequence to optimize the XRDT target function \cal F\ \cal P \ in a χ2 sense in order to recover the function fCtpd(r – r0) [\cal P is the parameter vector that characterizes the 3D function fCtpd(r – r0) in the algorithm search]. A theoretical framework based on the analytical solution of the Takagi-Taupin equations in the semi-kinematical approach is elaborated. In the case of true 2D imaging patterns (2D-IPs) with low counting statistics (noise-free), the joint qNLMSA algorithm enforces the target function \cal F \ \cal P \ to tend towards the global minimum even if the vector \cal P in the search is initially chosen rather a long way from the true one.This paper mathematically characterizes the tiny feasible regions within the vast 6D rotation-translation space in a full molecular replacement (MR) search. The capability to a priori isolate such regions is potentially important for enhancing robustness and efficiency in computational phasing in macromolecular crystallography (MX). The previous four papers in this series have concentrated on the properties of the full configuration space of rigid bodies that move relative to each other with crystallographic symmetry constraints. In particular, it was shown that the configuration space of interest in this problem is the right-coset space Γ\G, where Γ is the space group of the chiral macromolecular crystal and G is the group of rigid-body motions, and that fundamental domains FΓ\G can be realized in many ways that have interesting algebraic and geometric properties. The cost function in MR methods can be viewed as a function on these fundamental domains. This, the fifth and final paper in this series, articulates the constraints that bodies packed with crystallographic symmetry must obey.