Energy decomposition analysis method using density matrix formulation.

In this work, an energy decomposition analysis (EDA) method with the strategy of density matrix, called DM-EDA, is proposed on the basis of single reference electronic structure calculations. Different from traditional EDA methods, instead of an intermediate state wave function, the EDA terms in DM-EDA are expressed in the forms of the density matrix. This method can be carried out with various kinds of density matrices. With the efficient implementation, DM-EDA not only greatly improves the computational efficiency but also provides quantitative knowledge of intermolecular interactions with a large number of monomers.

Efficacy and safety of mesenchymal stem cell therapy in liver cirrhosis: a systematic review and meta-analysis.

AIM: Although the efficacy and safety of mesenchymal stem cell therapy for liver cirrhosis have been demonstrated in several studies. Clinical cases of mesenchymal stem cell therapy for patients with liver cirrhosis are limited and these studies lack the consistency of treatment effects. This article aimed to systematically investigate the efficacy and safety of mesenchymal stem cells in the treatment of liver cirrhosis. METHOD: The data source included PubMed/Medline, Web of Science, EMBASE, and Cochrane Library, from inception to May 2023. Literature was screened by the PICOS principle, followed by literature quality evaluation to assess the risk of bias. Finally, the data from each study's outcome indicators were extracted for a combined analysis. Outcome indicators of the assessment included liver functions and adverse events. Statistical analysis was performed using Review Manager 5.4. RESULTS: A total of 11 clinical trials met the selection criteria. The pooled analysis' findings demonstrated that both primary and secondary indicators had improved. Compared to the control group, infusion of mesenchymal stem cells significantly increased ALB levels in 2 weeks, 1 month, 3 months, and 6 months, and significantly decreased MELD score in 1 month, 2 months, and 6 months, according to a subgroup analysis using a random-effects model. Additionally, the hepatic arterial injection favored improvements in MELD score and ALB levels. Importantly, none of the included studies indicated any severe adverse effects. CONCLUSION: The results showed that mesenchymal stem cell was effective and safe in the treatment of liver cirrhosis, improving liver function (such as a decrease in MELD score and an increase in ALB levels) in patients with liver cirrhosis and exerting protective effects on complications of liver cirrhosis and the incidence of hepatocellular carcinoma. Although the results of the subgroup analysis were informative for the selection of mesenchymal stem cells for clinical treatment, a large number of high-quality randomized controlled trials validations are still needed.

The Influence of Hydrogen Bonds on the Roaming Reaction.

Roaming bypasses the conventional transition state and is a significant reaction pathway due to the unusual energy distributions of its products; however, its reaction pathway under external environmental interactions remains unclear. Herein, we report for the first time the roaming process of nitrobenzene, which is influenced by the hydrogen bonds (H-bonds) between nitro- and phenyl radicals and water molecules in the gas phase. Notably, despite the fact that the single water structure produces a higher but narrower barrier, whereas the double water structure leads to a lower but wider barrier, the roaming reaction still occurs. The underlying mechanism responsible for these influences of H-bonds is ascribed to the dramatically changed polarization and correlation interactions between the roaming radicals. The reaction rates and thermal perturbation probabilities are also remarkably influenced due to the presence of the H-bonds, by approximately 2 orders of magnitude. It is anticipated that this work will encourage the promising feasibility of introducing environmental molecules to modulate the roaming reaction.

Metal-enhanced fluorescence of single shell-isolated alloy metal nanoparticle.

A single silica-shell isolated Au-Ag alloy nanoparticle is used for investigating a metal-enhanced fluorescence effect. Well-dispersed alloy nanoparticles are prepared by the facile chemical method, and the property of local surface plasmon resonance is controlled by adjusting the metal component of the alloy and shell thickness. The distance dependence of fluorescence enhancement for a single Au-Ag alloy nanoparticle is studied systematically with different silica shell thickness ranging from 2 to 35 nm. The isolation shell not only adjusts the distance between metal surface and fluorophore emitters but also improves the chemical stability of the metal particle.

Tuning Upconversion Emission of ß-NaGdF4:Yb+/Ho3+ Nanorods Through Yb3+.

Yb3+/Ho3+ doped hexagonal NaGdF4 nanocrystals are synthesized through solvothermal method, for which pure hexagonal phased nanorods are presented. The concentration influence of Yb3+ ions on the sample morphology and fluorescence emission of Ho3+ is investigated. It is found that the sample size is changed from 25 nm to 125 nm and the upconversion emission is tuned from green to yellow when the concentration of Yb3+ ions is increased from 5.0 mol% to 50.0 mol%. The possible upconversion mechanism and the improvement of crystallinity are carefully investigated. It is suggested that the cross-relaxation process between Ho3+ ions promotes the red emission and quenches the green emission.