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In this study, nitrogen-sulfur codoped carbon quantum dots (N-S/CQDs) with various functions and properties were synthesized through a one-step method utilizing citric acid and cysteine as reaction substrates. The fluorescence of N-S/CQDs can be specifically quenched by permanganate ion (MnO4−), and the quenched fluorescence can be recovered by the presence of reduced glutathione (GSH). A fluorescence sensing system based on N-S/CQDs@MnO4− was developed and successfully applied for the determination of GSH in pharmaceutical preparations. Additionally, N-S/CQDs demonstrated broad-spectrum antibacterial activity, with minimum inhibitory concentrations of 32 μg/ml against Staphylococcus aureus (gram-positive bacterium) and 64 μg/ml against Escherichia coli (gram-negative bacterium). N-S/CQDs also proved effective for cell imaging, exhibiting excellent biocompatibility. These findings underscore the multifunctional characteristics and promising application potential of N-S/CQDs. Furthermore, this study provides a solid foundation for the development of multifunctional carbon quantum dots and the expansion of their applications in various fields.

Purpose: To construct optimal models for predicting the invasiveness and pathological subtypes of subsolid nodules (SSNs) based on CT radiomics and clinical features. Materials and Methods: This study was a retrospective study involving two centers. A total of 316 patients with 353 SSNs confirmed as atypical adenomatous hyperplasia (AAH), adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA) and invasive adenocarcinoma (IAC) were included from January 2019 to February 2023. Models based on CT radiomics and clinical features were constructed for classification of AAH/AIS and MIA, MIA and IAC, as well as lepidic-predominant adenocarcinoma (LPA) and acinar-predominant adenocarcinoma (APA). Receiver operating characteristic (ROC) curve was used to evaluate the model performance. Finally, the nomograms based on the optimal models were established. Results: The nomogram based on the combined model (AAH/AIS versus MIA) consisting of lobulation, the GGN-vessel relationship, diameter, CT value, consolidation tumor ratio (CTR) and rad-score performed the best (AUC=0.841), while age, CT value, CTR and rad-score were the significant features for distinguishing MIA from IAC, the nomogram based on these features performed the best (AUC=0.878). There were no significant differences in clinical features between LPA and APA, while the radiomics model based on rad-score showed good performance for distinguishing LPA from APA (AUC=0.926). Conclusions: The nomograms based on radiomics and clinical features could predict the invasiveness of SSNs accurately. Moreover, radiomics models showed good performance in distinguishing LPA from APA.

Parkinson’s disease (PD) is a chronic neurodegenerative disease with unclear pathogenesis that involves neuroinflammation and intestinal microbial dysbiosis. Intercellular adhesion molecule-1 (ICAM-1), an inflammatory marker, participates in neuroinflammation during dopaminergic neuronal damage. However, the explicit mechanisms of action of ICAM-1 in PD have not been elucidated. We established a subacute PD mouse model by the intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and observed motor symptoms and gastrointestinal dysfunction in mice. Immunofluorescence was used to examine the survival of dopaminergic neurons, expression of microglial and astrocyte markers, and intestinal tight junction-associated proteins. Then, we use 16 S rRNA sequencing to identify alterations in the microbiota. Our findings revealed that ICAM-1-specific antibody (Ab) treatment relieved behavioural defects, gastrointestinal dysfunction, and dopaminergic neuronal death in MPTP-induced PD mice. Further mechanistic investigations indicated that ICAM-1Ab might suppress neuroinflammation by inhibiting the activation of astrocytes and microglia in the substantia nigra and relieving colon barrier impairment and intestinal inflammation. Furthermore, 16 S rRNA sequencing revealed that the relative abundances of bacterial Firmicutes, Clostridia, and Lachnospiraceae were elevated in the PD mice. However, ICAM-1Ab treatment ameliorated the MPTP-induced disorders in the intestinal microbiota. Collectively, we concluded that the suppressing ICAM-1 might lead to the a significant decrease of inflammation and restore the gut microbial community, thus ameliorating the damage of DA neurons.

Parkinson's disease (PD) is the second most common neurodegenerative disease, and communication between the gut and brain (the gut-brain axis) has been found to be essential in behavior and cognitive function. However, the exact mechanisms underlying microbiota dysbiosis in PD progression have not yet been elucidated. Our study aimed to investigate the correlation between gut microbiota disturbances and feces metabolic disorders in PD. We used 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to induce PD models and observed mice's motor symptoms, dopaminergic (DA) neuron death, and gastrointestinal dysfunction. To identify alterations in microbiota and metabolome, feces were collected from mice and analyzed using 16 S ribosomal RNA sequencing feces metabolomics. Pearson analysis was utilized to investigate correlations between the abundances of gut microbiota components and the levels of gut microbiota metabolites, displaying their interaction networks. Our findings revealed a significant increase in Desulfobacterota in the PD mouse model and 151 differentially expressed fecal metabolites between PD and vehicle mice. Moreover, Pearson correlation analysis suggested that the protective factor N-acetyl-L-leucine (NALL) may be associated with neuroinflammation in the striatum and substantia nigra, which also had a negative relationship with the concentration of Desulfobacterota. Additionally, we found that oral administration of NALL alleviated MPTP-induced Motor Impairments and DA neuronal deficits. All in all, we concluded that the decrease of NALL might lead to a significant increase of Desulfobacterota in the MPTP model mouse and subsequently result in the damage of DA neurons via the gut-brain aix pathway.

The constitutive model is the basis and key for the application of materials in practical engineering. Numerical simulation has become one of the most important methods of scientific research, and an accurate constitutive model provides guarantees for the efficiency of numerical simulation. The multi-linear constitutive model is one of the most useful models for engineering. In this paper, different diameters of superelastic Shape Memory Alloy (SMA) wires are selected to investigate mechanical properties through experimentation. The influences of diameter, loading rate, temperature, and loading amplitude on the phase transformation stress, elastic modulus, residual strain, and energy dissipation properties are researched individually, and then the expressions of the influence law are given. Correction coefficients considering the effects of diameter, loading rate, temperature, and loading amplitude are employed to modify the multi-linear constitutive model. A multi-linear dynamic constitutive model considering multiple influence factors is given. Finite element analysis is carried out by introducing the modified multi-linear dynamic constitutive model into the finite element software, and the simulation results are compared to the testing results. The modified multi-linear dynamic constitutive model has high accuracy and can guide the engineering and numerical studies.

Synthetic rutile was prepared from titanium slag melt with a low amount of additive (B2O3) and low energy consumption in our previous work. The mechanism by which B2O3 promotes the precipitation of the rutile phase during the cooling and crystallization of titanium slag melt is not clear and needs further theoretical study. The effects of B2O3 on the structure and properties of titanium slag melt were investigated by molecular dynamics simulations in this study. The B2O3 content has a remarkable effect on the coordination environments of B, Ti and Si atoms, while it has no distinct effect on the position of the central peak in the bond length distributions of BOp, TiOm and SiOn polyhedra. As the B2O3 content increases from 0% to 24%, some of the Ti–O bonds in the oxygen connections are replaced by the B–O bonds and the structural strength of the titanium slag melt is reduced. As the B2O3 content increases from 0% to 24%, the self-diffusion coefficients of all ions increase, and their order remains the same. As the B2O3 content increases from 0% to 24%, the viscosity of the titanium slag melt decreases from 0.079 to 0.032 Pa·s. The addition of B2O3 reduces the overall strength, increases the diffusion coefficients and decreases the viscosity of the titanium slag melt. Such changes are conducive to the oxidation of low-valent titanium and to the precipitation of rutile in titanium slag melt. This work may lay the foundation for the efficient preparation of synthetic rutile by adding B2O3 to the titanium slag melt.

Recent research on the oxygen reduction reaction in has mainly focused on the design and synthesis of non-noble metal catalysts to overcome the cost limitations of precious metals that have a high catalytic activity. The catalytic activity of non-noble metal catalysts has been greatly improved over a large number of studies in the field, but there is still no obvious advantage over precious metal catalysts. In this work, an electrocatalyst with high limiting current density for the oxygen reduction reaction was successfully prepared by codoping a tungsten carbide matrix with Fe and N. The performance of the catalyst was characterized by various physical and electrochemical techniques. The limiting current density in the oxygen reduction reaction (ORR) can reach 6.644 mA cm−2, and the catalyst also has good half-wave and onset potentials. In addition to the excellent stability and methanol tolerance of the cathode process under alkaline conditions, the catalyst also exhibited the four-electron transfer mechanism as well as good ORR kinetics, and the yield of H2O2 was close to 0. This catalyst with its excellent properties is of significance in guiding research on non-noble metal catalysts with comparable performance to traditional noble metal catalysts.