OPLS-based force fields (FFs) have been shown to provide accurate bulk-phase properties for a wide variety of imidazolium-based ionic liquids (ILs). However, the ability of OPLS to reproduce an IL solvent structure is not as well-validated given the relative lack of high-level theoretical or experimental data available for comparison. In this study, ab initio molecular dynamics (AIMD) simulations were performed for three widely used ILs: the 1-butyl-3-methylimidazolium cation with chloride, tetrafluoroborate, or hexafluorophosphate anions, that is, [BMIM][Cl], [BMIM][BF], and [BMIM][PF], respectively, as a basis for further assessment of two unique IL FFs: the ±0.8 charge-scaled OPLS-2009IL FF and the OPLS-VSIL FF. The OPLS-2009IL FF employs a traditional all-atom functional form, whereas the OPLS-VSIL FF was developed using a virtual site that offloads negative charge to inside the plane of the ring with careful attention given to reproducing hydrogen bonding. Detailed comparisons between AIMD and the OPLS FFs were made based on radial distribution functions (RDFs), combined distribution functions (CDFs), and spatial distribution functions (SDFs) to examine cation-anion interactions and π-π stacking between the imidazolium rings. While both FFs were able to correctly capture the general solvent structure of these popular ILs, the OPLS-VSIL FF quantitatively reproduced interaction distances more accurately. In addition, this work provides further insights into the different short- and long-range structure patterns of these popular ILs.
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http://dx.doi.org/10.1021/acs.jpcb.2c01636 | DOI Listing |
Front Biosci (Landmark Ed)
January 2025
Division of Biochemistry and Molecular Biology, Federal State Budgetary Educational Institution of Higher Education "Siberian State Medical University" of the Ministry of Health of Russia, 634050 Tomsk, Russia.
Background: Over the past five years, the pregnancy rate in assisted reproductive technology (ART) programs in Russia has remained relatively stable. The aim of this study was to assess the distribution of monocyte and macrophage subsets in the blood and follicular fluid of infertile women undergoing assisted reproductive technology.
Methods: The study involved 45 women with a mean age of 35 ± 4.
Front Biosci (Landmark Ed)
January 2025
Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Fujian Medical University, Fujian Provincial Key Laboratory of Stomatology, National Regional Medical Center, Binhai Campus of The First Affiliated Hospital, 350005 Fuzhou, Fujian, China.
Background: In this study, we prepared a porous gradient scaffold with hydroxyapatite microtubules (HAMT) and chitosan (CHS) and investigated osteogenesis induced by these scaffolds.
Methods: The arrangement of wax balls in the mold can control the size and distribution of the pores of the scaffold, and form an interconnected gradient pore structure. The scaffolds were systematically evaluated and for biocompatibility, biological activity, and regulatory mechanisms.
Genome Biol Evol
January 2025
Institut Sophia Agrobiotech, INRAE, Université Côte d'Azur, CNRS, Sophia Antipolis, France.
Carbohydrate-active enzymes (CAZymes) involved in the degradation of plant cell walls and/or the assimilation of plant carbohydrates for energy uptake are widely distributed in microorganisms. In contrast, they are less frequent in animals, although there are exceptions, including examples of CAZymes acquired by horizontal gene transfer (HGT) from bacteria or fungi in several of phytophagous arthropods and plant-parasitic nematodes. Although the whitefly Bemisia tabaci is a major agricultural pest, knowledge of HGT-acquired CAZymes in this phloem-feeding insect of the Hemiptera order (subfamily Aleyrodinae) is still lacking.
View Article and Find Full Text PDFJ Integr Neurosci
January 2025
Department of Neurosurgery, Affiliated Hospital of Southwest Medical University, 646000 Luzhou, Sichuan, China.
Background: Recent studies suggest that the anterior limb of the internal capsule may be an area of convergence for multiple compulsion loops. In this study, the role of different dopaminergic compulsion loops in the mechanism of obsessive-compulsive disorder (OCD) was investigated by selectively damaging dopaminergic neurons or fibers in the corresponding targets with 6-hydroxydopamine (6-OHDA) and depicting the anatomical map of various compulsion loops located in the anterior limb of the internal capsule.
Methods: A total of 52 male Sprague Dawley (SD) rats were exposed to either saline (1 mL/kg, NS group, n = 6) or quinpirole (QNP, dopamine D2-agonist, 0.
Ann Clin Transl Neurol
January 2025
NEUROFARBA Department, Neurosciences Section, University of Florence, Florence, Italy.
Objectives: We aim to investigate cognitive phenotype distribution and MRI correlates across pediatric-, elderly-, and adult-onset MS patients as a function of disease duration.
Methods: In this cross-sectional study, we enrolled 1262 MS patients and 238 healthy controls, with neurological and cognitive assessments. A subset of 222 MS patients and 92 controls underwent 3T-MRI scan for brain atrophy and lesion analysis.
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