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Zinc oxide nanoparticles (ZnONPs) are widely utilized across various industries, raising concerns about their potential toxicity, especially in the respiratory system. This study explores the role of autophagy, regulated by microtubule-associated protein 1A/1B-light chain 3B (LC3B), in ZnONPs-induced toxicity using both in vivo (LC3B knockout mice) and in vitro (BEAS-2B cells) models. Our findings demonstrate that LC3B-regulated autophagy mitigates ZnONPs-induced epithelial cell dysfunction and acute lung injury. In the absence of LC3B, oxidative stress, inflammation, and intracellular zinc accumulation are exacerbated, resulting in mitochondrial dysfunction and epithelial cell death. In vitro, LC3B knockdown disrupted zinc ion transporter expression and impaired mitophagic flux in BEAS-2B cells. Treatment with zinc ion chelators alleviated these toxic effects, confirming that free zinc ions play a critical role in driving ZnONPs toxicity. These findings highlight that targeting autophagy and maintaining zinc homeostasis could offer therapeutic strategies to reduce ZnONPs-induced lung damage. [ABSTRACT FROM AUTHOR]

Aim Methodology Results Conclusion Regenerative endodontic procedures (REPs) are tissue engineering‐based treatments aimed at regenerating the pulp‐dentin complex. However, these procedures are not widely practiced or well‐known among dentists due to a lack of training. This study aims to develop a practical hands‐on training model for REPs to enhance students' theoretical knowledge and practical skills.A cost‐effective, easy‐to‐operate, and reusable training model for preclinical training of REPs was developed. A total of 125 undergraduates were divided into an experimental group (REPs model) and a control group (traditional teaching). The students' theoretical knowledge and operational skills were assessed through examinations and practical assessments. Student perceptions were assessed by questionnaires.The experimental group achieved higher scores in theoretical knowledge and operational skills compared to the control group (p < .001). The process evaluation of the experimental group demonstrated a high level of proficiency in executing root canal disinfection steps, with pass rates ranging from 93.5% to 95.2%. Students in both groups perceived the model as valuable for improving critical thinking, stimulating interest, and enhancing their confidence and proficiency.The developed REPs training model is a practical and effective tool for teaching and training regenerative endodontics. It bridges the gap between preclinical and clinical education, enhancing students' confidence and clinical competence. [ABSTRACT FROM AUTHOR]

Bacterial dysbiosis accompanies carcinogenesis in malignancies such as colon and liver cancer, and has recently been implicated in the pathogenesis of pancreatic ductal adenocarcinoma (PDA).sup.1. However, the mycobiome has not been clearly implicated in tumorigenesis. Here we show that fungi migrate from the gut lumen to the pancreas, and that this is implicated in the pathogenesis of PDA. PDA tumours in humans and mouse models of this cancer displayed an increase in fungi of about 3,000-fold compared to normal pancreatic tissue. The composition of the mycobiome of PDA tumours was distinct from that of the gut or normal pancreas on the basis of alpha- and beta-diversity indices. Specifically, the fungal community that infiltrated PDA tumours was markedly enriched for Malassezia spp. in both mice and humans. Ablation of the mycobiome was protective against tumour growth in slowly progressive and invasive models of PDA, and repopulation with a Malassezia species--but not species in the genera Candida, Saccharomyces or Aspergillus--accelerated oncogenesis. We also discovered that ligation of mannose-binding lectin (MBL), which binds to glycans of the fungal wall to activate the complement cascade, was required for oncogenic progression, whereas deletion of MBL or C3 in the extratumoral compartment--or knockdown of C3aR in tumour cells--were both protective against tumour growth. In addition, reprogramming of the mycobiome did not alter the progression of PDA in Mbl- (also known as Mbl2) or C3-deficient mice. Collectively, our work shows that pathogenic fungi promote PDA by driving the complement cascade through the activation of MBL. In humans and mouse models, the mycobiome of pancreatic ductal adenocarcinoma tumours is markedly enriched in Malassezia species compared to that of normal pancreas, which implicates these pathogenic fungi in oncogenesis., Author(s): Berk Aykut [sup.1] , Smruti Pushalkar [sup.2] , Ruonan Chen [sup.1] , Qianhao Li [sup.2] , Raquel Abengozar [sup.1] , Jacqueline I. Kim [sup.1] , Sorin A. Shadaloey [sup.1] [...]

The gut microbiome shapes local and systemic immunity. The liver is presumed to be a protected sterile site. As such, a hepatic microbiome has not been examined. Here, we showed a liver microbiome in mice and humans that is distinct from that of the gut and is enriched in Proteobacteria. It undergoes dynamic alterations with age and is influenced by the environment and host physiology. Fecal microbial transfer experiments revealed that the liver microbiome is populated from the gut in a highly selective manner. Hepatic immunity is dependent on the microbiome, specifically the bacteroidetes species. Targeting bacteroidetes with oral antibiotics reduced hepatic immune cells by approximately 90%, prevented antigen-presenting cell (APC) maturation, and mitigated adaptive immunity. Mechanistically, our findings are consistent with presentation of bacteroidetes-derived glycosphingolipids to NKT cells promoting CCL5 signaling, which drives hepatic leukocyte expansion and activation, among other possible host-microbe interactions. Collectively, we reveal a microbial/glycosphingolipid/NKT/CCL5 axis that underlies hepatic immunity., Introduction Gut microbiota represent the most abundant and diverse collection of commensal organisms in the body (1). The intestinal microbiome plays a fundamental role in shaping the host immune system [...]

In this work, an innovative ionic liquid functionalized star-shaped polymer is synthesized by coupling star-polycaprolactone with benzimidazolium (star-PCL-Bim), and statically coated into a capillary column for gas chromatographic (GC) separations. The fabricated star-PCL-Bim capillary column with moderate-polar nature reveals a high column efficiency of 3598 plates/m for n-dodecane at 120 °C, and advantageous distinguishing ability (R > 1.5) for 9 aromatic isomer mixtures and 12 cis-/trans-isomers. Its excellent resolving capacity can be credited to the architecture of star-PCL-Bim, the PCL arms, and π-electron-rich benzimidazolium cations, and it results in a quite different retention behavior of star-PCL-Bim from that of star-PCL and commercial HP-35 columns, with "dual-nature" selectivity in separating a mixture including 29 compounds. These favorable chromatographic characteristics demonstrate the great application potential of this material in GC, and provide a prospective strategy to obtain high-performance stationary phases. [ABSTRACT FROM AUTHOR]

Solar-induced chlorophyll fluorescence (SIF) has been found to be a useful indicator of vegetation's gross primary productivity (GPP). However, the directional SIF observations obtained from a canopy only represent a portion of the total fluorescence emitted by all the leaf photosystems because of scattering and reabsorption effects inside the leaves and canopy. Hence, it is crucial to downscale the SIF from canopy level to leaf level by modeling fluorescence escape probability (fesc) for improved comprehension of the relationship between SIF and GPP. Most methods for estimating fesc rely on the assumption of a "black soil background," ignoring soil reflectance and the effect of scattering between soils and leaves, which creates significant uncertainties for sparse canopies. In this study, we added a correction factor considering soil reflectance, which was modeled using the Gaussian process regression algorithm, to the semi-empirical NIRv/FAPAR model and obtained the improved fesc model accounting for soil reflectance (called the fesc_GPR-SR model), which is suitable for near-infrared SIF downscaling. The evaluation results using two simulation datasets from the Soil–Canopy–Observation of Photosynthesis and the Energy Balance (SCOPE) model and the Discrete Anisotropic Radiative Transfer (DART) model showed that the fesc_GPR-SR model outperformed the NIRv/FAPAR model, especially for sparse vegetation, with higher accuracy for estimating fesc (R2 = 0.954 and RMSE = 0.012 for SCOPE simulations; R2 = 0.982 and RMSE = 0.026 for DART simulations) compared with the NIRv/FAPAR model (R2 = 0.866 and RMSE = 0.100 for SCOPE simulations; R2 = 0.984 and RMSE = 0.070 for DART simulations). The evaluation results using in situ observation data from multi-species canopies also suggested that the leaf-level SIF calculated by the fesc_GPR-SR model tracked better with photosynthetic active radiation absorbed by green components (APARgreen) for sparse vegetation (R2 = 0.937, RMSE = 0.656 mW/m2/nm) compared with the NIRv/FAPAR model (R2 = 0.921, RMSE = 0.904 mW/m2/nm). The leaf-level SIF calculated by the fesc_GPR-SR model was less sensitive to observation angles and differences in canopy structure among multiple species. These results emphasize the significance of accounting for soil reflectance in the estimation of fesc and demonstrate that the fesc_GPR-SR model can contribute to further exploring the physiological mechanism between SIF and GPP. [ABSTRACT FROM AUTHOR]

Mars' surface is characterized by a weathered layer of regolith and exposed rock exposures that are the results of long‐term geological processes. The Mars Rover Penetrating Radar (RoPeR) on board the Zhurong rover of China's first Mars mission (Tianwen‐1) has been investigating the fine structure and dielectric properties of the martian regolith in the southern Utopia Planitia. The permittivity of the regolith within 5 m of the landing zone is 3.6−2.0+3.1 ${3.6}_{-2.0}^{+3.1}$, and the average loss tangent is 0.0174−0.0053+0.0053 ${0.0174}_{-0.0053}^{+0.0053}$. The high lossy parameter suggests the possible cause for the missing subsurface reflectors in the landing region detected by either in‐situ radar or orbiter radars. The permittivity distribution map has been derived to show permittivity varying with depth and location. The high dispersion of both permittivity and loss tangent values along the traverse path indicates relatively heterogeneous material distribution on the landing site compared to an airless body such as the Moon. Plain Language Summary: A layer of regolith covers the surface of Mars, which is the result of geologic processes that occurred over millions to billions of years. Compared to the observations from satellites, the Zhurong rover of China's first Mars mission (Tianwen‐1) had a closer look at the properties of the regolith layer in the explored region within southern Utopia Planitia. There is evidence that the exposed materials might be related to aqueous activities. Local landforms on the surface suggest the possible presence of buried volatiles, like water ice. The radar instrument (RoPeR) on board the rover can expose subsurface structures and the dielectric properties of the regolith layer at high‐resolution, to assess their composition. The loss tangent results suggest that water ice is not the main component of the local martian regolith at some depth. The scattering distribution of radar profile along the traveling path and heterogeneous subsurface features show more diverse surface processes and weaker space weathering effects on Mars than those on the airless Moon. Key Points: The dielectric properties of martian regolith at the Tianwen‐1 landing site suggest that water ice is not the dominant componentThe radar image and permittivity and loss tangent distribution maps show a high heterogeneity of subsurface materialsCompared to the lunar regolith, the martian regolith shows more diverse surface processes and weaker space weathering effects [ABSTRACT FROM AUTHOR]

A novel calix[6] arene polymer stationary phase (C6A-PEG) is reported that combines the π-electron-rich cavity of calix[6] arene (C6A) with polyethylene glycol (PEG) units for gas chromatography (GC). Thermogravimetric analysis revealed a 5% weight loss of C6A-PEG at 318 °C, and its static-coated capillary column showed high efficiency of 2924 plates/m (k = 3.48) determined by 1-octanol at 120 °C. As a result, the moderate polar C6A-PEG column showed clearly advantageous performance for the Grob reagent and a mixture of 25 analytes with high selectivity for hydrogen-bonded acids. Also, it exhibited high resolving performance for various isomer mixtures, in particular high-resolution performance (R > 2.2) for the challenging toluidine and dimethylaniline systems with distinct advantages compared to the C6A and PEG columns (R < 1.5 for some pairs). This work demonstrates the potential of calixarene-based polymers as novel stationary phases for gas chromatographic analysis. [ABSTRACT FROM AUTHOR]

Amid global attention on the growth of China’s e-commerce economy, prior research has focused more on demonstrating the digital dividends created by this new economy than on addressing the social inequalities that arise. One presumption in particular is that e-commerce economy will leverage the deterritorializing effects of digital technologies to create more equal opportunities for consumers in remote areas. Based on fieldwork with e-traders in Yiwu City, Zhejiang Province, and customers from a rural county of Tibet, this article argues that while e-commerce economy has eliminated trade barriers to a certain extent, it has also drawn new geographic boundaries and engendered new social divides in China. By exploring the e-traders’ hierarchal conception of baoyouguo (literally, “the free-shipping kingdom”) and their subsequent differentiated treatments of customers from different regions, this study illuminates China’s emerging e-commerce geography and its consequences in the Internet age. [ABSTRACT FROM AUTHOR]