Among various types of chromophore-solvent interactions, the entanglement of chromophore and solvent orbitals, when significant, can cause the chromophore frontier orbitals to spread over to nearby solvent molecules, introducing partial charge-transfer character to the lowest excitations of the chromophore and lowering the excitation energies. While highly intuitive, the physical details of such orbital entanglement effects on the excitation energies of chromophores have yet to be fully explored. Here, using two well-known biochromophores (oxyluciferin and p-hydroxybenzyledene imidazolinone) as examples, we show that the chromophore-solvent orbital entanglements can be elucidated using two quantum mechanical embedding schemes: density matrix embedding theory and absolutely localized molecular orbitals.
View Article and Find Full Text PDF(1) Background: In recent years, the increasing emergence of multidrug-resistant pathogens in pig farms has begun to pose a severe threat to animal welfare and, by extension, public health. In this study, we aimed to explore the biological characteristics and genomic features of bacteriophages that are capable of lysing porcine multidrug-resistant , which was isolated from sewage. In doing so, we provided a reference for phage therapies that can be used to treat multidrug-resistant strains.
View Article and Find Full Text PDFWe revisit the naked transition metal cation (Ti) and methanol reaction and go beyond the standard Landau-Zener (LZ) picture when modeling the intersystem crossing (ISC) rate between the lowest doublet and quartet states. We use both (i) unconstrained Born-Oppenheimer molecular dynamics (BOMD) calculations with an approximate two-state method to estimate population transfer between spin diabats and (ii) constrained dynamics to explore energetically accessible portions of the - 1 crossing seam, where is the total number of internal degrees of freedom. Whereas previous LZ calculations (that necessarily relied on the Condon approximation to be valid) fell short and predicted much slower crossing probabilities than shown in experiment, we show that ISC can occur rapidly because the spin-orbit coupling (SOC) between the doublet and quartet surfaces can vary by 2 orders of magnitude (depending on where in the seam the crossing occurs during dynamics) and the crossing region is revisited multiple times during a dynamics run of a few hundred femtoseconds.
View Article and Find Full Text PDFThe Born-Oppenheimer framework stipulates that chemistry and physics occur on potential energy surfaces VBO(X) parameterized by a nuclear coordinate X, which are built by diagonalizing a BO Hamiltonian ĤBO(X). However, such a framework cannot recover many measurable chemical and physical features, including vibrational circular dichroism spectra. In this article, we show that a phase-space electronic Hamiltonian ĤPS(X,P), parameterized by both nuclear position X and momentum P, with a similar computational cost as solving ĤBO(X), can recover not just experimental vibrational circular dichroism signals but also a meaningful electronic current density that explains the features of the vibrational circular dichroism rotational strengths.
View Article and Find Full Text PDFShanghai Kou Qiang Yi Xue
August 2024
Purpose: To explore the effect of narrative medicine teaching practice on the narrative ability and empathy ability of dental interns and establish an effective narrative medicine teaching system.
Methods: From June 2022 to May 2023, atotal of 34 dental undergraduate students participating in clinical practice were divided into two groups, with 14 students in experimental group and 20 in control group. During clinical internships, the experimental group took narrative medicine into practice including theoretical lectures, close reading, parallel chart, seminars and so on.
Background: In clinical practice, the buccal approach is typically the primary choice for endodontic microsurgery. Owing to the thickness of the buccal bone plate, the distance between the buccal bone plate and palatal lesion location, and soft tissue traction, the palatal approach may be more suitable for microsurgery for apical periodontitis of the palatal roots of the maxillary molars. However, the length of the palatal root, location of the greater palatine artery (GPA) and foramen (GPF), and surgical field of observation make palatal surgery challenging.
View Article and Find Full Text PDFBackground: The curriculum system is a central component in achieving the goals and specifications of talent training schemes. However, problems and difficulties exist in curriculum provision due to a lack of curriculum system design logic. This study aimed to investigate the correlation between the university curriculum system and graduate quality and to reveal the design logic of the curriculum system.
View Article and Find Full Text PDFJ Chem Theory Comput
September 2024
We show empirically that a phase-space non-Born-Oppenheimer electronic Hamiltonian approach to quantum chemistry (where the electronic Hamiltonian is parametrized by both nuclear position and momentum, (,)) is both a practical and accurate means to recover vibrational circular dichroism spectra. We further hypothesize that such a phase-space approach may lead to very new dynamical physics beyond spectroscopic circular dichroism, with potential implications for understanding chiral induced spin selectivity (CISS), noting that classical phase-space approaches conserve the total nuclear plus electronic momentum, whereas classical Born-Oppenheimer approaches do not (they conserve only the nuclear momentum).
View Article and Find Full Text PDFApxII is a vaccine antigen used to protect against porcine contagious pleuropneumonia, which is a significant threat to the pig industry. Here, we aimed to improve the proteolytic degradation stability of ApxII during its secretion by establishing a complete screening process of stable variants through bioinformatics and site-directed mutagenesis. We employed a combination of semi-rational and rational design strategies to create 34 single-point variants of ApxII.
View Article and Find Full Text PDFTo objectively quantify changes in steroid hormones in organisms caused by adverse environmental loads, we developed a simple and sensitive UPLC-MS/MS (ultra-performance liquid chromatography triple quadrupole mass spectrometry) method for the simultaneous determination of 18 steroid hormones on the HPG axis. This analytical method was based on liquid extraction and a multimode electrospray and atmospheric pressure chemical ionization (ESCi) source, which was optimized by mass spectrometry, liquid phase and pretreatment for the quantification of cholesterol (CH), aldosterone (A), cortisone (E), hydrocortisone (F), 21-deoxycortisol (21-DF), corticosterone (B), 11-deoxycortisol (11-DF), androstenedione (A), estradiol (E), estrone (E), 2-methoxyestradiol (2-MeE), 21-hydroxyprogesterone (21-OHP), 17-α hydroxyprogesterone (17α-OHP), testosterone (T), dehydroepiandrosterone (DHEA), progesterone (P), dihydrotestosterone (DHT), and pregnenolone (P). The method exhibits linearity in the analyte-concentration range 0.
View Article and Find Full Text PDFNitrogen oxides (NO) emissions can cause air pollution that is harmful to human health, even producing serious ecological problems. Whether it is diluted in the air or not, the management and valorization of NO from industrial emissions have been constrained by technology and finance. This study shows that red soil can be used as a photocatalyst to convert NO into soil nitrate nitrogen (NO-N) in the soil.
View Article and Find Full Text PDFObjectives: The first purpose of this project was to determine whether an interdisciplinary and cross-grade teaching model impacts students' learning enthusiasm and their views on this teaching method. The second purpose was to determine whether the model positively impacted students' theoretical course exam scores.
Methods: We recruited 203 pre-clinical undergraduate dental students, including 104 third- and 99 fourth-grade students.
Background: One noteworthy concern within the realm of education is the level of engagement demonstrated by students. Among the factor that can have a crucial role in this domain is teacher support, especially emotional support which has an impact on several aspects of learners' education. Furthermore, various studies have investigated the relationship between Emotional Intelligence (EI) and learners' engagement.
View Article and Find Full Text PDFWe propose a simple procedure for visualizing the electron density changes (EDC) during a chemical reaction, which is based on a mapping of rectangular grid points for a stationary structure into (distorted) positions around atoms of another stationary structure. Specifically, during a small step along the minimum energy pathway (MEP), the displacement of each grid point is obtained as a linear combination of the motion of all atoms, with the contribution from each atom scaled by the corresponding Hirshfeld weight. For several reactions (identity S2, Claisen rearrangement, Diels-Alder reaction, [3+2] cycloaddition, and phenylethyl mercaptan attack on pericosine A), our EDC plots showed an expected reduction of electron densities around severed bonds (or those with the bond-order lowered), with the opposite observed for newly-formed or enhanced chemical bonds.
View Article and Find Full Text PDFTetrabromobisphenol A (TBBPA) and tetrachlorobisphenol A (TCBPA) have been widely used as flame retardants. However, their potential health risks to organisms have raised concerns, particularly for liver toxicity. Present study aimed to explore the toxic effects of TCBPA and TBBPA on black-spotted frogs (Pelophylax nigromaculatus) liver oxidative stress, autophagy, and lipid accumulation.
View Article and Find Full Text PDFA photocatalytic synthesis of difluoromethylated selenides from selenosulfonates is described here. Bench-stable difluoromethyl phosphonium salt [PhPCFH]Br reacts smoothly with selenosulfonates to give a series of functionalized difluoromethylated selenides in moderate to good yields via a radical process. This protocol is free of a stoichiometric base and reductant, has tolerance of functional groups, and has successful late-stage modification of bioactive molecules, which provides facile access to molecules of pharmaceutical relevance.
View Article and Find Full Text PDFStroke Vasc Neurol
October 2023
Background: Acute brain ischaemia elicits pronounced inflammation, which aggravates neural injury. However, the mechanisms governing the resolution of acute neuroinflammation remain poorly understood. In contrast to regulatory T and B cells, group 2 innate lymphoid cells (ILC2s) are immunoregulatory cells that can be swiftly mobilised without antigen presentation; whether and how these ILC2s participate in central nervous system inflammation following brain ischaemia is still unknown.
View Article and Find Full Text PDFBackground And Purpose: Conflicting reports of obesity paradox have led to confusion about weight management strategies for post-stroke patients. The main purpose of this study is to determine whether the obesity paradox measured by body mass index (BMI) or by waist-to-height ratio (WHtR) is real.
Methods: We evaluated the association of general obesity measured by BMI, and abdominal obesity measured by WHtR with 1-year all-cause mortality, recurrence of stroke and combined vascular events of acute ischemic stroke (AIS) patients in a cohort -- the Third China National Stroke Registry (CNSR-III).
Patients with intracerebral hemorrhage (ICH) often suffer from heterogeneous long-term neurological deficits, such as cognitive decline. Our ability to measure secondary brain injury to predict the long-term outcomes of these patients is limited. We investigated whether the blood neurofilament light chain (NfL) can monitor brain injury and predict long-term outcomes in patients with ICH.
View Article and Find Full Text PDFWith the growing global popularity of traditional medicine and natural drugs, especially in Southeast Asia, the quality of traditional Chinese medicines (TCMs) has attracted the attention of regulators. China's major TCM export destinations, such as South Korea, Japan, and Europe, have formulated strict maximum residue limits (MRLs) of pesticides in TCMs. Therefore, a sensitive and high-throughput method for the simultaneous determination of 101 pesticide residues in and extracts of was established, involving gel permeation chromatography (GPC) coupled with gas chromatography-ion trap mass spectrometry (GC-ITMS).
View Article and Find Full Text PDFThe nonadiabatic phenomena, which are characterized by a strong coupling between electronic and nuclear motions, are ubiquitous. The nonadiabatic effect of the studied system can be significantly affected by the surrounding environment, such as solvents, in which such nonadiabatic process takes place. It is essential to develop the theoretical models to simulate these processes while accurately modeling the solvent environment.
View Article and Find Full Text PDFThis work is devoted to deriving and implementing analytic second- and third-order energy derivatives with respect to the nuclear coordinates and external electric field within the framework of the hybrid quantum mechanics/molecular mechanics method with induced charges and dipoles (QM/DIM). Using these analytic energy derivatives, one can efficiently compute the harmonic vibrational frequencies, infrared (IR) and Raman scattering (RS) spectra of the molecule in the proximity of noble metal clusters/nanoparticles. The validity and accuracy of these analytic implementations are demonstrated by the comparison of results obtained by the finite-difference method and the analytic approaches and by the full QM and QM/DIM calculations.
View Article and Find Full Text PDFEndodontic microsurgery is important for preservation of natural teeth with symptomatic apical periodontitis when conventional endodontic treatment is neither feasible nor effective. The thick buccal cortex, poor visibility, and potential neurovascular complications can make microsurgical procedures of mandibular second molars infeasible. With the aid of cone-beam computed tomography, the bony lid approach was applied in 10 cases of endodontic microsurgery of mandibular second molars at the VIP Center, Hangzhou Stomatology Hospital between 2019 and 2020.
View Article and Find Full Text PDFWorld J Clin Cases
September 2022
Background: Swelling after apical microsurgery is a postoperative reaction and may reduce quality of life during healing.
Aim: To evaluate periapical swelling after apical microsurgery and determine potential risk factors.
Methods: Ninety-eight apical microsurgery patients were selected for this study.