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Summary: Computer supported design of materials with tailored properties is an important part of computational science so that developments of new effective algorithms is a key issue. Molecular magnetism deals with complex objects described by the quantum physics and their simulations come up against the computational constraints. In this work, we consider a numerical version of a recently developed hybrid approach that combines the ab initio DFT method with the exact diagonalization of the microscopic Hubbard model (HM). The latter avoids the prior perturbative framework but increases computing resources needed for solving the eigenvalue problem of the matrix representation of HM. We demonstrate that in the case of the ring‐shape molecular nanomagnets the computational demands can be curbed due to efficient numerical matrix construction algorithms provided. These algorithms pertain both to the calculation of the single nonzero matrix elements and to their localization in the final sparse matrix that is subsequently diagonalized. Their implementation executed on a simple six‐core‐computer system and the Mathematica environment leads to a significant gain in the computing time for the exemplary chromium‐based molecule denoted Cr8$$ {}_8 $$, running the code sequentially. We claim, referring to the numerical diagonalization of the spin Hamiltonian matrices, that the parallelization flaws related to the high‐level programming approach can be all removed, porting the code to the appropriate HPC environment. A prospective implementation of the code, based on some dedicated and optimized mathematical libraries, will ultimately open a window for further applications of the Hubbard model in molecular magnetism. [ABSTRACT FROM AUTHOR]

This article describes benefits of the application of zinc oxide submicron particles (ZnO SMPs), zinc oxide nanoparticles (ZnO NPs) and ZnO NPs combined with silver NPs (ZnO + Ag NPs) in chrysanthemum micropropagation. Single node explants of Chrysanthemum × morifolium (Ramat.) Hemsl. ‘UTP Burgundy Gold (UBG)’ and ‘UTP Pinky Gold (UPG)’ were inoculated on the Murashige and Skoog (MS) medium and treated with 100 mg · L−1, 200 mg · L−1, or 400 mg · L−1 ZnO SMPs, ZnO NPs (1.5% H2O), ZnO NPs (6% H2O), ZnO + 0.1% Ag NPs (1.5% H2O), ZnO + 0.1% Ag NPs (6% H2O), ZnO + 1% Ag NPs (1.5% H2O) and ZnO + 1% Ag NPs (6% H2O). Generally, the tested materials stimulated the growth and development of plantlets. In ‘UBG’, the most prominent treatments affecting increases in the number of leaves, micropropagation coefficient, shoot length and shoot FW/DW weight included 400 mg · L−1 ZnO SMPs and 100 mg · L−1 ZnO NPs (6% H2O). In ‘UPG’, the treatments with 200 mg · L−1 ZnO + 0.1% Ag NPs (6% H2O) and 200 mg · L−1 ZnO + 1% Ag NPs (6% H2O) were the most successful. The latter treatment stimulated an intensive development of root systems in the two studied cultivars. High values of leaf area, perimeter and width were reported in both cultivars for 400 mg · L−1 ZnO + 1% Ag NPs (6% H2O). As compared to the control, the treated plants were characterised by a similar or, most often, lower content of chlorophylls and carotenoids. The randomly amplified polymorphic DNA (RAPD) and start codon targeted polymorphism (SCoT) marker system analyses of the 400 mg · L−1 ZnO SMPs/ZnO NPs/ZnO + Ag NPs-treated chrysanthemums confirmed their genetic fidelity with the control plants. The obtained results can be implemented in the commercial large-scale production of chrysanthemums.

Having a strong understanding of the epidemiology, pathophysiology, and clinical management of Gastrointestinal Stromal Tumors (GIST) is critical for clinicians who may encounter this cancer. The quiz below is designed for medical students, residents, fellows, and practicing physicians to test their knowledge and review key concepts for understanding GIST., (Copyright © 2024 Society for Surgery of the Alimentary Tract. Published by Elsevier Inc. All rights reserved.)

Accurate risk stratification in acute intermediate-risk pulmonary embolism (PE) is essential. Current prediction scores lack the ability to forecast impending clinical decline. The Pulmonary Embolism Progression (PEP) score aims to predict short-term clinical deterioration (respiratory failure or hemodynamic instability within 72 h) in patients with intermediate-risk PE. This single-center retrospective cohort study analyzed patients with intermediate PE. The outcome of interest was respiratory failure or hemodynamic instability within 72 h. A multivariate logistic regression identified five predictive variables for the final PEP score: use of > 4 L/min of supplemental oxygen above baseline, lactate > 2.0 mmol/L, high-sensitivity cardiac troponin T (hs-cTnT) > 40 ng/L, tricuspid annular plane systolic excursion (TAPSE) < 13 mm, and the combination of central and subsegmental clot. The derivation cohort included 117 patients, and the validation cohort included 70 patients. The area under the receiver operating characteristic (AUROC) curve for the derivation cohort was 0.8671 (95% CI: 0.7946, 0.9292), and for the validation cohort, it was 0.9264 (95% CI: 0.8680, 0.9847). A PEP score of 4 points yielded the highest combination of sensitivity (93%) and specificity (65%). Each incremental point increase in the PEP score raised the probability of clinical deterioration by a factor of 1.933. The PEP score is a reliable tool for predicting the likelihood of clinical deterioration in intermediate-risk PE patients within 72 h, potentially aiding in timely clinical decision-making and improving patient outcomes., (© 2024. The Author(s).)

Two new paramagnetic supramolecular helicates with the formula (X@[Ni 2 L 3 ]) 3+ (X = Cl, or Br; L = a bis-pyrazolylpyridine ligand) have been prepared and are described. Helicates of this metal are very rare with virtually no prior examples of them acting as hosts of anionic species. The persistence of the new assemblies in solution has been demonstrated unambiguously by mass spectrometry and paramagnetic 1 H NMR. This has allowed us to establish the preference of the coordination [Ni 2 ] host for Cl - over Br - , in agreement with DFT calculations. These results show the promise of the use of metallohelicates as suitable systems for the selective encapsulation of specific anions in solution.