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The complexity of the energy levels in Fe ii has made it difficult to theoretically interpret its observational emission spectrum. However, addressing this challenge could provide valuable insights into the main sequence of QSOs using "eigenvector 1" and the chemical evolution of the Universe. Although the templates based on I Zw 1 are widely used, their universality remains unexplained. To address this, we utilized the CLOUDY spectral synthesis code to generate theoretical blends of Fe ii optical emission near the H β region. Our results indicate that the optimal cloud density and photon flux align with previous studies at gas density 1011 cm−3 and photon flux 1020.5 cm−2 s−1. We discovered a broad parameter region that fits the data well, encompassing a diverse range of densities and photon fluxes. This helps to explain the general applicability of optical templates. Additionally, we investigated the effects of different spectral energy distributions (SEDs), Eddington ratios, turbulence, and cloud column densities and found that they provided a sufficiently broad range for typical emitting clouds. We found different SEDs had a negligible impact on the template shape, further expanding the usability of empirical templates. However, they significantly affected the absolute intensity of Fe ii emission, consistent with previous research. Furthermore, we determined that a turbulence of approximately 100 km s−1 is necessary to produce sufficiently strong optical Fe ii, and either a column density greater than 1024 cm−2, which is typical for Fe ii UV emission, or an abundance higher than solar is preferred. [ABSTRACT FROM AUTHOR]

Background: Blended teaching is an effective approach that combines online and offline teaching methods, leading to improved outcomes in medical education compared to traditional offline teaching. In this study, we examined the impact of blended teaching in clinical skills training, a medical practice course. Methods: This study involved forty-eight undergraduate students studying clinical medicine in the fifth semester at Wuhan University of Science and Technology. The students were divided into two groups: the control group, which received traditional offline teaching, and the experimental group, which received hybrid teaching. Following the completion of the 4-month course, both groups underwent the Objective Structured Clinical Examination (OSCE) to evaluate their proficiency in clinical skills. Furthermore, the experimental group was given a separate questionnaire to gauge their feedback on the Blended Teaching approach. Results: Based on the OSCE scores, the experimental group outperformed the control group significantly (P<0.05). The questionnaire results indicated that a majority of students (54.2%, 3.71 ± 1.06) believed that blended teaching is superior to traditional offline teaching, and a significant number of students (58.3%, 3.79 ± 1.15) expressed their willingness to adopt blended teaching in other courses. Furthermore, students in the experimental group displayed varying levels of interest in different teaching contents, with emergency medicine (79.2%), internal medicine (70.8%), and surgery (66.7%) being the most popular among them. Conclusions: This research demonstrates for the first time that blended teaching can achieve a good pedagogical effectiveness in the medical practice course, clinical skills training and practice. Moreover, in different teaching contents, the teaching effects are different. In the content of Emergency Medicine and Surgery, which is more attractive to students, the application of blended teaching could result in a better pedagogical outcome than other contents. [ABSTRACT FROM AUTHOR]

Oxidation–reduction post-translational modifications (redox-PTMs) are chemical alterations to amino acids of proteins. Redox-PTMs participate in the regulation of protein conformation, localization and function, acting as signalling effectors that impact many essential biochemical processes in the cells. Crucially, the dysregulation of redox-PTMs of proteins has been implicated in the pathophysiology of numerous human diseases, including neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. This review aims to highlight the current gaps in knowledge in the field of redox-PTMs biology and to explore new methodological advances in proteomics and computational modelling that will pave the way for a better understanding of the role and therapeutic potential of redox-PTMs of proteins in neurodegenerative diseases. Here, we summarize the main types of redox-PTMs of proteins while providing examples of their occurrence in neurodegenerative diseases and an overview of the state-of-the-art methods used for their detection. We explore the potential of novel computational modelling approaches as essential tools to obtain insights into the precise role of redox-PTMs in regulating protein structure and function. We also discuss the complex crosstalk between various PTMs that occur in living cells. Finally, we argue that redox-PTMs of proteins could be used in the future as diagnosis and prognosis biomarkers for neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

The applications of fucoidan in the food industry were limited due to its high molecular weight and low solubility. Moderate degradation was required to depolymerize fucoidan. A few studies have reported that fucoidan has potential antibacterial activity, but its antibacterial mechanism needs further investigation. In this study, the degraded fucoidans were obtained after ultraviolet/hydrogen peroxide treatment (UV/H2O2) at different times. Their physicochemical properties and antibacterial activities against Staphylococcus aureus and Escherichia coli were investigated. The results showed that the average molecular weights of degraded fucoidans were significantly decreased (up to 22.04 times). They were mainly composed of fucose, galactose, and some glucuronic acid. Fucoidan degraded for 90 min (DFuc-90) showed the strongest antibacterial activities against Staphylococcus aureus and Escherichia coli, with inhibition zones of 27.70 + 0.84 mm and 9.25 + 0.61 mm, respectively. The minimum inhibitory concentrations (MIC) were 8 mg/mL and 4 mg/mL, respectively. DFuc-90 could inhibit the bacteria by damaging the cell wall, accumulating intracellular reactive oxygen species, reducing adenosine triphosphate synthesis, and inhibiting bacterial metabolic activity. Therefore, UV/H2O2 treatment could effectively degrade fucoidan and enhance its antibacterial activity. [ABSTRACT FROM AUTHOR]

Radiotherapy is one of the standard therapeutic regimens for medulloblastoma (MB). Tumor cells utilize DNA damage repair (DDR) mechanisms to survive and develop resistance during radiotherapy. It has been found that targeting DDR sensitizes tumor cells to radiotherapy in several types of cancer, but whether and how DDR pathways are involved in the MB radiotherapy response remain to be determined. Single‐cell RNA sequencing was carried out on 38 MB tissues, followed by expression enrichment assays. Fanconi anemia group D2 gene (FANCD2) expression was evaluated in MB samples and public MB databases. The function of FANCD2 in MB cells was examined using cell counting assays (CCK‐8), clone formation, lactate dehydrogenase activity, and in mouse orthotopic models. The FANCD2‐related signaling pathway was investigated using assays of peroxidation, a malondialdehyde assay, a reduced glutathione assay, and using FerroOrange to assess intracellular iron ions (Fe2+). Here, we report that FANCD2 was highly expressed in the malignant sonic hedgehog (SHH) MB subtype (SHH‐MB). FANCD2 played an oncogenic role and predicted worse prognosis in SHH‐MB patients. Moreover, FANCD2 knockdown markedly suppressed viability, mobility, and growth of SHH‐MB cells and sensitized SHH‐MB cells to irradiation. Mechanistically, FANCD2 deficiency led to an accumulation of Fe2+ due to increased divalent metal transporter 1 expression and impaired glutathione peroxidase 4 activity, which further activated ferroptosis and reduced proliferation of SHH‐MB cells. Using an orthotopic mouse model, we observed that radiotherapy combined with silencing FANCD2 significantly inhibited the growth of SHH‐MB cell‐derived tumors in vivo. Our study revealed FANCD2 as a potential therapeutic target in SHH‐MB and silencing FANCD2 could sensitize SHH‐MB cells to radiotherapy via inducing ferroptosis. © 2024 The Pathological Society of Great Britain and Ireland. [ABSTRACT FROM AUTHOR]

Oily sludge is a hazardous solid waste, hazardous ingredients (hazardous elements and heavy metals) in pyrolysis products have the potential for secondary pollution. The distribution of hazardous elements (N/S/Cl) during the pyrolysis of oily sludge was determined at different pyrolysis temperatures (350–750°C), and the potential ecological risk of heavy metals (Zn/Cu/Cd/Cr/Pb) in the solid residue was evaluated. The results showed that N-pollutants in oily sludge were mainly distributed at higher pyrolysis temperatures (550°C), S and Cl-pollutants were mainly distributed at 450°C. The leaching concentration of Zn metal in oily sludge was 119.73 mg/L, which has exceeded the concentration limit (100 mg/L) stipulated by GB 16,889–2008. The pyrolysis treatment could reduce the leaching rate of Zn metal to 18.39 mg/L Moreover, the risk assessment code (RAC) values for Zn showed a very high risk environmental risk level. Pyrolysis treatment could reduce the RAC value of Zn and change the environmental risk level of Zn to low risk. The results of this study provide a theoretical basis for the pyrolysis treatment of oily sludge and the control of harmful ingredients. [ABSTRACT FROM AUTHOR]

Litter and root decomposition is an important source of soil organic matter and nutrients. To ascertain the contribution of litter and root to natural grassland nutrients in rocky desertification areas, from March 2017 to January 2018, the continuous soil column method, collector method, and litter decomposition method were used to study the soil nutrients, litter and root biomass, decomposition, and nutrient release of potential, moderate, and severe rocky desertification grasslands, as well as their responses to rocky desertification. The results showed that the litter and root decomposition rate showed a trend of being first fast and then slow, and the decomposition rate of litter and root was greater than 50% after 300 days. The annual litter decomposition rates of potential, moderate, and severe rocky desertification grasslands were 69.98%, 62.14%, and 49.79%, respectively, and the annual decomposition rates of root were 73.64%, 67.61%, and 64.09%, respectively. With a deepening degree of rocky desertification, the litter and root decomposition rate decreased. The decomposition coefficients, k , of litter in potential, moderate, and severe rocky desertification grasslands were 1.128, 0.896, and 0.668, respectively, and the decomposition coefficients, k , of root were 1.152, 1.018, and 0.987, respectively. The nutrient release processes of litter and root were different, and the release mode ultimately manifests as "release". In rocky desertification grasslands, the organic carbon (OC), total nitrogen (TN), total phosphorus (TP), and total potassium (TK) released by litter and root decomposition were 18.93-263.03 g·m -2 ·yr -1 , 1.79-5.59 g·m -2 ·yr -1 , 0.18-0.47 g·m -2 ·yr -1 , and 0.66-3.70 g·m -2 ·yr -1 , respectively. The contribution of root to soil nutrients was greater than that of litter. The degree of rocky desertification was negatively correlated with the biomass, decomposition rate, and nutrient return amount of litter and root. The results of this study provide direct field evidence and illustrate the contribution of litter and root decomposition in rocky desertification grasslands to soil nutrients.

Chili bean paste is a traditional flavor sauce, and its flavor compounds are closely related to its microflora. This study focused on investigating the content of bioactive compounds, flavor compounds, and microbial communities during the post-ripening fermentation of chili bean paste, aiming to provide a reference for improving the flavor of chili bean paste by regulating microorganisms. Compared to no post-ripening fermentation, the content of organic acids increased significantly ( p < 0.05), especially that of citric acid (1.51 times). Glutamic acid (Glu) was the most abundant of the 17 free amino acids at 4.0 mg/g. The aroma profiles of the samples were significantly influenced by fifteen of the analyzed volatile compounds, especially methyl salicylate, methyl caproate, and 2-octanol (ROAV > 1). Latilactobacillus (27.45%) and Pseudomonas (9.01%) were the dominant bacterial genera, and Starmerella (32.95%) and Pichia (17.01%) were the dominant fungal genera. Weissella , Lacticaseibacillus , Pichia , and Kazachstania had positive effects on volatile flavoring compounds, which enriched the texture and flavor of the chili bean paste. Therefore, the microbial-community activity during the post-ripening fermentation is the key to enhance the flavor quality of the product.

With the rapid rise in the gig economy driven by advancements in digital technology and financial technology, this study focuses on the work experiences and psychological perceptions of food delivery riders in platform-based employment. This study used a sample of food delivery riders from 19 cities in China (such as Shanghai, Beijing, Guangzhou, etc.) and multiple delivery platforms (such as Meituan, Ele.me) to collect data through a combination of online and offline questionnaires. The impact relationship between perceived fairness, organizational trust, and organizational identity of food delivery riders was examined through factor analysis, structural equation modeling, and mediation effect modeling. The results of the survey and statistical analysis indicate that fairness perception and its dimensions (distributive fairness, procedural fairness, and interactional fairness) significantly influence riders' organizational identification, with organizational trust serving as a critical mediating factor. The integration of digital technology has substantially enhanced the operational efficiency of platform-based employment by enabling real-time tracking, transparent communication, and data-driven decision-making. Innovations in financial technology, such as digital payment systems and financial management tools, offer riders safer and more convenient compensation methods, thereby contributing to their financial stability and fostering trust in the platform. The establishment of trust alleviates the riders' concerns regarding compensation stability and bolsters their optimistic attitudes toward accessing platform resources and meeting their needs. This study provides significant insights and recommendations for leveraging digital technology and financial technology to improve the relationship and operational efficiency between riders and platform enterprises. [ABSTRACT FROM AUTHOR]

Eleven kinds of Camellia oleifera seed oils (CSOs) were evaluated in terms of chemical constituents, antioxidant activities, acid value (AV) as well as peroxide value (POV). These CSOs contained abundant β-sitosterol, squalene, α-tocopherol and phenolics, in which the squalene was the distinct constituent with the content between 45.8±0.8 and 184.1±5.5 mg/kg. The β-sitosterol ranging from 143.7±4.8 to 1704.6±72.0 mg/kg contributed a considerable content to total accompaniments. Palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid were present in these CSOs, in which the dominant fatty acid was oleic acid with the content between 59.66±0.72 and 82.89±2.16 g/100 g. The AV ranged from 0.1±0.0 to 1.3±0.0 mg KOH/g, and the POV was between 0.1±0.0 and 1.0±0.0 g/100 g. These CSOs showed antioxidant activity based on DPPH and ABTS radical scavenging assay. Both α-tocopherol and β-sitosterol contents showed a positive correlation with DPPH and ABTS values, respectively, while the α-tocopherol content showed a negative correlation with AV. These results suggested that CSO can be categorized into high oleic acid vegetable oil with abundant active constituents, of which the quality presented variation among different origins. These accompaniments may contribute to the delay of its quality deterioration. [ABSTRACT FROM AUTHOR]

This paper presents a particle swarm optimization-guided maximum likelihood estimation enabled (MLE) adaptive extended Kalman filter (EKF) with unknown inputs algorithm for estimating the dynamic nonlinear thermal states for an indoor heating ventilation and air conditioning system. The concept of MLE has been introduced to enhance the speed of convergence of the filtering parameters in adaptive EKF. The nonlinear indoor environment has been modelled employing equivalent RC network taking relative humidity into account. At the outset, an EKF-based method accommodating the unknown inputs and an adaptive estimator-based variant of it are developed for estimating the temperature of the walls of a laboratory-scale realistic environment. Subsequently the proposed scheme comes into play to deal with the scenarios associated with undesirable divergence and poor initialization utilizing the metaheuristically adapted optimal regularizer. The proposed technique outperforms the other contemporary state-of-the-art counterparts in terms of mean squared error. [ABSTRACT FROM AUTHOR]

To explore the population structures and dynamics of Rhododendron shrub communities at different stages of succession in northwest Guizhou, China, this study examined the populations of Rhododendron annae and Rhododendron irroratum shrub with two different stages. A space-for-time substitution was employed to establish the diameter class/height structures, static life tables, and survival/mortality rate/disappearance rate curves of both Rhododendron populations with different orders of succession. Their structural and quantitative dynamics were analyzed, and their development trends were predicted. The results showed that, quantitatively, the populations of R. annae and R. irroratum in the two Rhododendron communities with different orders of succession were dominated by age classes one, two, and three as well as height classes i, ii, and iii. The number of Rhododendron plants at the three age classes and the three height classes accounted for 97.61-100% of the total. The quantitative dynamic indices of R. annae and R. irroratum were both greater than 0, with and without considering external interference. In terms of age class and height structures, both Rhododendron populations were expanding populations, presenting "inverted-J-shaped" and irregular pyramid patterns. There was a sufficient number of young individuals, but few or no old individuals. Both survival curves of the populations of R. annae and R. irroratum in the two Rhododendron communities with different orders of succession belonged to the Deevy-II type. In the late stage of succession, the mortality curves and disappearance curves of both Rhododendron populations in these communities presented a trend of increasing first and then decreasing with increasing age class. This result indicates that at each age class, R. annae and R. irroratum showed a trend of gradual increase after two, four, and six years. In brief, the populations of R. annae and R. irroratum have rich reserves of seedlings and saplings, but high mortality and disappearance rates. In this context, it is necessary to reduce human interference and implement targeted conservation measures to promote the natural renewal of Rhododendron populations.