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The structural parameters, electron localization functions, electron paramagnetic resonance (EPR) parameters, formation energies, and thermodynamic transition levels of various oxygen vacancy defects in amorphous silica are comprehensively and integrally investigated by using density functional theory. The trends of changes in the oxygen vacancy defect structure and electron localization induced by the increase in distance between defective silicon atoms are clearly identified. It is shown that the dimer configuration may be the potential structure of the E δ ′ center. For the back-projected unpuckered configuration and the puckered configuration, whose EPR parameters are more consistent with the experimental values of the E γ ′ center, the unpaired electron localized on the sp3 hybridized silicon atom is a common feature. Due to the three-coordinated oxygen atom in the forward-oriented configuration, the EPR parameters are closest to those of the E α ′ center. Transformations of oxygen vacancy defects under different charge states are studied by sequentially adding and removing electrons. The thermodynamic transition level analysis reveals that the dimer and forward configurations may behave as deep traps for electron accumulation. The back-projected puckered fourfold-coordinated and fivefold-coordinated configurations are comparatively stable and may be able to function as shallow traps for electron transport. The neutral double unpuckered, neutral back-projected puckered fourfold-coordinated, and neutral back-projected unpuckered configurations are more likely to lose electrons during hole trapping. As the bias voltage is repeatedly changed, the defect density of the puckered configuration may reduce, while that of the dimer and unpuckered configuration may take an opposite trend. [ABSTRACT FROM AUTHOR]

This article explores the use of breast cancer organoids (BCOs) in personalized medicine. The study reveals that BCOs effectively preserve molecular characteristics in hormone receptor-positive and HER2-positive breast cancers, but there are notable differences in triple-negative breast cancer (TNBC) due to culture conditions. BCOs exhibit a decrease in immune and stromal cells compared to primary breast cancer tissues, but an increase in epithelial cells. The study also investigates genomic concordance, gene expression profiling, and drug sensitivity in BCOs. The findings suggest that BCOs are valuable for studying epithelial components of tumors, but may have limitations in accurately predicting drug sensitivity in TNBC. The article provides supporting information for a research project and is authored by a group of individuals whose names are listed at the end of the article. [Extracted from the article]

The rapid advancement of tumor immunotherapies poses challenges for the tools used in cancer immunology research, highlighting the need for highly effective biomarkers and reproducible experimental models. Current immunotherapy biomarkers encompass surface protein markers such as PD‐L1, genetic features such as microsatellite instability, tumor‐infiltrating lymphocytes, and biomarkers in liquid biopsy such as circulating tumor DNAs. Experimental models, ranging from 3D in vitro cultures (spheroids, submerged models, air–liquid interface models, organ‐on‐a‐chips) to advanced 3D bioprinting techniques, have emerged as valuable platforms for cancer immunology investigations and immunotherapy biomarker research. By preserving native immune components or coculturing with exogenous immune cells, these models replicate the tumor microenvironment in vitro. Animal models like syngeneic models, genetically engineered models, and patient‐derived xenografts provide opportunities to study in vivo tumor‐immune interactions. Humanized animal models further enable the simulation of the human‐specific tumor microenvironment. Here, we provide a comprehensive overview of the advantages, limitations, and prospects of different biomarkers and experimental models, specifically focusing on the role of biomarkers in predicting immunotherapy outcomes and the ability of experimental models to replicate the tumor microenvironment. By integrating cutting‐edge biomarkers and experimental models, this review serves as a valuable resource for accessing the forefront of cancer immunology investigation. [ABSTRACT FROM AUTHOR]

Single atom catalysts (SACs) show potential application for highly efficient water splitting. Herein, we designed Co single atoms (SAs) dispersed on N and P co‐doped porous carbon nanofibers as electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The configuration of Co SAs is proved to coordinate with 4 N/O atoms. The long‐range interactions between doped P atoms and Co−N4(O) sites could modulate the electronic structures of M−N4(O) sites, which greatly reduce the adsorption energies of HER and OER intermediates at metal sites. Density Functional Theory calculations reveal that CoSA/CNFs exhibits optimized HER and OER kinetics when P coordinates with two N atoms. The atomically dispersed Co electrocatalyst exhibits the low overpotentials of 61, 89 and 390 mV for acidic HER, alkaline HER and OER at 10 mA cm−2 current density, along with the Tafel slope of 54, 143 and 74 mV dec−1, respectively. This work demonstrates the prospect of utilizing di‐heteroatom‐doping transition metal SACs, and provides a novel and general strategy for the preparation of SACs. [ABSTRACT FROM AUTHOR]

Background: Early detection is critical for improving the survival of breast cancer (BC) patients. Exhaled breath testing as a non-invasive technique might help to improve BC detection. However, the breath test accuracy for BC diagnosis is unclear. Methods: This multi-center cohort study consecutively recruited 5047 women from four areas of China who underwent BC screening. Breath samples were collected through standardized breath collection procedures. Volatile organic compound (VOC) markers were identified from a high-throughput breathomics analysis by the high-pressure photon ionization–time-of-flight mass spectrometry (HPPI-TOFMS). Diagnostic models were constructed using the random forest algorithm in the discovery cohort and tested in three external validation cohorts. Results: A total of 465 (9.21%) participants were identified with BC. Ten optimal VOC markers were identified to distinguish the breath samples of BC patients from those of non-cancer women. A diagnostic model (BreathBC) consisting of 10 optimal VOC markers showed an area under the curve (AUC) of 0.87 in external validation cohorts. BreathBC-Plus, which combined 10 VOC markers with risk factors, achieved better performance (AUC = 0.94 in the external validation cohorts), superior to that of mammography and ultrasound. Overall, the BreathBC-Plus detection rates were 96.97% for ductal carcinoma in situ, 85.06%, 90.00%, 88.24%, and 100% for stages I, II, III, and IV BC, respectively, with a specificity of 87.70% in the external validation cohorts. Conclusions: This is the largest study on breath tests to date. Considering the easy-to-perform procedure and high accuracy, these findings exemplify the potential applicability of breath tests in BC screening. [ABSTRACT FROM AUTHOR]