Chirality plays a critical role in the biochemistry of life and often only one enantiomeric series is observed (homochirality). Only a few natural products have been obtained as racemates, e.g.
View Article and Find Full Text PDFIsoorientin (ISO) is a natural lignan glycoside flavonoid found in various plants, including Charcot and Stonecrop. ISO exhibits diverse physiological and pharmacological effects, such as antioxidative, anti-inflammatory, hepatoprotective, antiviral, antianxiety, and anti-myocardial ischaemic properties, as well as lipid metabolism regulation. This study investigated the impact of ISO supplementation on oxidative stress and lipid accumulation in porcine early embryos, along with its underlying mechanisms.
View Article and Find Full Text PDFBackground: Current research has found that factors such as gender, age, and family history can predict the efficacy of electroconvulsive therapy (ECT) in individuals with schizophrenia. In our clinical practice, we anecdotally observed that tobacco smokers and alcohol drinkers with schizophrenia seemed to respond more effectively to ECT than non-smokers and non-drinkers. The current study aimed to examine whether history of tobacco smoking or alcohol consumption serve as indicators for predicting therapeutic efficacy of ECT in individuals with schizophrenia.
View Article and Find Full Text PDFDiosmetin (DIOS), a natural flavonoid monomer derived from lemons and present in various plants such as spearmint and spider moss, exhibits antioxidant, anti-inflammatory, and antiaging properties. Nonetheless, its impact on early embryonic development in pigs remains unexplored. This study aimed to determine the influence of DIOS supplementation in an in vitro culture (IVC) medium on porcine embryo development and to elucidate the underlying mechanisms.
View Article and Find Full Text PDFAccurately simulating non-Markovian quantum dynamics in system-bath coupled problems remains challenging. In this work, we present a novel memory truncation scheme for the iterative quasi-adiabatic propagator path integral (iQuAPI) method to improve accuracy. Conventional memory truncation in iQuAPI discards all influence functional beyond a certain time interval, which is not effective for problems with a long memory time.
View Article and Find Full Text PDFTree tensor network states (TTNS) decompose the system wavefunction to the product of low-rank tensors based on the tree topology, serving as the foundation of the multi-layer multi-configuration time-dependent Hartree method. In this work, we present an algorithm that automatically constructs the optimal and exact tree tensor network operators (TTNO) for any sum-of-product symbolic quantum operator. The construction is based on the minimum vertex cover of a bipartite graph.
View Article and Find Full Text PDFQuantum transport in molecular junctions has attracted great attention. The charge motion in a molecular junction can cause geometric deformation, leading to strong electron phonon coupling, which was often overlooked. We have formulated a nearly exact method to assess the time-dependent current and occupation number in the molecular junction modeled by the electron-phonon coupled bridge state using the time-dependent density matrix renormalization group (TD-DMRG) method.
View Article and Find Full Text PDFMaterials (Basel)
July 2023
To address the issues of low detection accuracy, slow detection speed, high missed detection rate, and high false detection rate in the detection of surface defects on pre-impregnated composite materials during the automated tape laying and winding process, an improved YOLOv5 (You Only Look Once version 5) algorithm model was proposed to achieve the high-precision, real-time detection of surface defects. By leveraging this improvement, the necessity for frequent manual interventions, inspection interventions, and subsequent rework during the automated lay-up process of composite materials can be significantly reduced. Firstly, to improve the detection accuracy, an attention mechanism called "CA (coordinate attention)" was introduced to enhance the feature extraction ability, and a Separate CA structure was used to improve the detection speed.
View Article and Find Full Text PDFExciton coherence length (ECL) characterizes the spatial extent of coherently delocalized excited states of molecular aggregates. Constructive/destructive superpositions of coherent molecular dipoles lead to superradiance/subradiance, where the radiative rate is enhanced/suppressed compared to that of a single molecule. Longer ECLs correspond to faster/slower radiative rates for superradiant/subradiant aggregates.
View Article and Find Full Text PDFOrganic/polymeric materials are of emerging importance for thermoelectric conversion. The soft nature of these materials implies strong electron-phonon coupling, often leading to carrier localization. This poses great challenges for the conventional Boltzmann transport description based on relaxation time approximation and band structure calculations.
View Article and Find Full Text PDFUsing a photonic quantum computer for boson sampling has demonstrated a tremendous advantage over classical supercomputers. It is highly desirable to develop boson sampling algorithms for realistic scientific problems. In this work, we propose a hybrid quantum-classical sampling (HQCS) algorithm to calculate the optical spectrum for complex molecules considering Duschinsky rotation effects and anharmonicity.
View Article and Find Full Text PDFDensity matrix renormalization group (DMRG) and its time-dependent variants have found widespread applications in quantum chemistry, includingelectronic structure of complex bio-molecules, spectroscopy for molecular aggregates, and charge transport in bulk organic semiconductors. The underlying wavefunction ansatz for DMRG, matrix product state (MPS), requires mapping degrees of freedom (DOF) into a one-dimensional topology. DOF ordering becomes a crucial factor for DMRG accuracy.
View Article and Find Full Text PDFBackground: Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive lipid accumulation in hepatocytes. The involvement of programmed cell death 4 (Pdcd4) in inflammation and metabolic diseases has been widely reported. However, the precise regulatory role of Pdcd4 in hepatocytic lipid metabolism and NAFLD is not well known.
View Article and Find Full Text PDFWe propose a method to calculate the spectral functions of many-body systems by Chebyshev expansion in the framework of matrix product states coupled with canonical orthogonalization (coCheMPS). The canonical orthogonalization can improve the accuracy and efficiency significantly because the orthogonalized Chebyshev vectors can provide an ideal basis for constructing the effective Hamiltonian in which the exact recurrence relation can be retained. In addition, not only the spectral function but also the excited states and eigenenergies can be directly calculated, which is usually impossible for other MPS-based methods such as time-dependent formalism or correction vector.
View Article and Find Full Text PDFGallbladder cancer (GBC) is the most common biliary tract malignancy worldwide. Although a growing number of studies have explored the mechanism of GBC, thus far, few molecules have been discovered that can be utilized as specific biomarkers for the early diagnosis and therapeutic treatment of GBC. Recent studies have shown that exosomes not only participate in the progression of tumors, but also carry specific information that can define multiple cancer types.
View Article and Find Full Text PDFThe nonlocal electron-phonon couplings in organic semiconductors responsible for the fluctuation of intermolecular transfer integrals has been the center of interest recently. Several irreconcilable scenarios coexist for the description of the nonlocal electron-phonon coupling, such as phonon-assisted transport, transient localization, and band-like transport. Through a nearly exact numerical study for the carrier mobility of the Holstein-Peierls model using the matrix product states approach, we locate the phonon-assisted transport, transient localization and band-like regimes as a function of the transfer integral (V) and the nonlocal electron-phonon couplings (ΔV), and their distinct transport behaviors are analyzed by carrier mobility, mean free path, optical conductivity and one-particle spectral function.
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