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The history of vegetation and climate change during the Cenozoic has been reconstructed by systematically analyzing the sporopollen assemblage from Borehole ZKA02 in Beihai, Guangxi. Through the analysis of spore-pollen data, four sporopollen assemblages can be recognized. From the Early Miocene to the Middle Miocene, this area was covered mainly by deciduous broad-leaved mixed forest–wet meadow vegetation, with a mild and semi-humid climate. From the end of the Middle Miocene to the early Late Miocene, the study area was dominated by coniferous and broad-leaved mixed forest-wet meadow vegetation, with mild and semi-humid. The middle Late Miocene was a mixed deciduous broad-leaved forest–wet meadow vegetation, with increasing conifers and ferns, and the climate was warm and humid. In the late Late Miocene to Pliocene, it was deciduous broad-leaved mixed forest–wet meadow vegetation. The species of evergreen broad-leaved trees in tropical rain forests and subtropical low mountains increased obviously, and the fern molecules decreased obviously. The climate in the Late Pliocene was warm and semi-arid, drier than the previous three stages. Spore-pollen assemblages reflected the climate change characteristics during the Neogene, which have good comparability with the trend of global climate change.

Alkaline soil is widely distributed in China. Its rational utilization is an effective measure to solve land shortage and improve the environment. Alfalfa is characterized by strong salt and alkali tolerance and high yield and protein content. Nitrogen (N) and phosphorus (P) are the main nutrients for plant growth, and N metabolism is one of the primary forms of plant metabolism, which plays a vital role in quality and yield formation. The exploration of the effect of N and P on N metabolism and alfalfa growth will provide a theoretical basis for scientific fertilization for alfalfa in the alkaline soil of the Yinchuan Plain of the Hetao Basin. Therefore, a 2-year experiment of N and P addition was conducted. Six treatments were set up with a randomized block design, including without N (WN), medium N (MN), high N (HN), without P (WP), medium P (MP), and high P (HP). It was found that the MN and MP treatments increased plant height, stem diameter, stem/leaf, dry/fresh, and dry matter of alfalfa. The HN and HP treatments inhibited alfalfa biomass formation. The MN and MP treatments increased key products and enzymes of leaf N metabolism of alfalfa and promoted activities of leaf nitrate reductase (NR), glutamine synthase (GS), glutamate synthase (GOGAT), glutamic-oxalacetic transaminase (GOT), and glutamic-pyruvate transaminase (GPT), and inhibited activities of leaf protease of alfalfa. The MN and MP treatments increased contents of leaf N, P, ammonium nitrogen (NH4+-N), nitrate nitrogen (NO3−-N), total chlorophyll, and protein and reduced leaf chlorophyll a/b and amino acid, results after HN and HP treatments were opposite. The correlation among leaf P, N, NO3−-N, amino acid, and protein reached significant levels (P < 0.01). It is suggested that MN and MP treatments can improve the yield and quality of alfalfa by increasing key products and enzymes of N metabolism and can be adopted to promote alfalfa production in the alkaline soil of the Yinchuan Plain of the Hetao Basin.

The production of fuel and membranes for proton exchange membrane fuel cells (PEMFCs) typically involves disparate materials, highlighting the need for a bifunctional material capable of integrating hydrogen supply and proton conduction. Herein, we modified a donor–acceptor covalent organic framework (PyBT-COF) by converting its cyano groups into carboxyl groups, resulting in PyBT-COF-COOH. The modification significantly enhances the photocatalytic hydrogen production activity, achieving a rate of 8.15 mmol g−1 h−1 with Pt as the cocatalyst, over 2.8 times higher than that of the original PyBT-COF. It also demonstrates an impressive quantum efficiency of 5.10% at 420 nm due to the improved hydrophilicity and carrier separation. Additionally, the rich proton carriers and exchange binding sites within PyBT-COF-COOH also give it a notable proton conductivity of 4.91 × 10−3 S cm−1 at 353 K and 98% RH. Upon visible light irradiation, the proton conductivity of PyBT-COF-COOH can be further increased to three times compared to that under normal conditions (1.5 × 10−2 S cm−1 at 353 K and 98% RH). This study suggests an inspiration for developing and utilizing such bifunctional COF materials in terms of solar energy conversion. [ABSTRACT FROM AUTHOR]

Aroma in food plays an important role in food perception and acceptance, which depends on various mixtures of volatile organic compounds (VOCs). Moreover, VOCs are of great significance for aroma identification. In this study, headspace solid-phase microextraction (HS-SPME) combined with gas chromatography–mass spectrometry (GC-MS) technology was used to determine the VOCs in 10 pear syrups. A total of 127 VOCs were quantitatively determined, including 9 common VOCs and 46 characteristic VOCs of 10 pear syrups. The pear syrups were divided into three categories by cluster analysis, and thirty-eight differential VOCs were obtained using orthogonal partial least squares discrimination analysis (OPLS-DA) and fourteen key VOCs were selected by odor activity value (OAV). It was revealed that the key and common aroma components of pear syrups were butanoic acid, methyl ester, 2-methyl-, methyl ester and Hexanoic acid, and ethyl ester. The characteristic and differential VOCs were 10-Undecen-1-ol, Hexadecanal, n-Propylacetate, Cyclohexanol, 5-methyl-2-(1-methylethyl)-, (1S,2R,5S)-, Methional, Disulfide, dimethyl, 8-Nonenoic acid, ethyl ester, Naphthalene, 1,2-dihydro-1,1,6-trimethyl-, 3H-Purin-6-amine, N,N,3-trimethyl-, 2-Octanol,2,6-dimethyl-, Furyl hydroxymethyl ketone, Heptane, 2,2,4,6,6-pentamethyl-, and Butanoic acid,2-methyl-,methyl ester. The above results showed that different pear syrups had rich diversity in aroma compounds, with some components being shared among them while others are exclusive to specific syrups. [ABSTRACT FROM AUTHOR]

Background: Patients with non‐small cell lung cancer (NSCLC) with liver metastasis have a poor prognosis, and there are no reliable biomarkers for predicting disease progression. Currently, no recognized and reliable prediction model exists to anticipate liver metastasis in NSCLC, nor have the risk factors influencing its onset time been thoroughly explored. Methods: This study conducted a retrospective analysis of 434 NSCLC patients from two hospitals to assess the association between the risk and timing of liver metastasis, as well as several variables. Results: The patients were divided into two groups: those without liver metastasis and those with liver metastasis. We constructed a nomogram model for predicting liver metastasis in NSCLC, incorporating elements such as T stage, N stage, M stage, lack of past radical lung cancer surgery, and programmed death ligand 1 (PD‐L1) levels. Furthermore, NSCLC patients with wild‐type EGFR, no prior therapy with tyrosine kinase inhibitors (TKIs), and no prior radical lung cancer surgery showed an elevated risk of early liver metastasis. Conclusion: In conclusion, the nomogram model developed in this study has the potential to become a simple, intuitive, and customizable clinical tool for assessing the risk of liver metastasis in NSCLC patients following validation. Furthermore, it provides a framework for investigating the timing of metachronous liver metastasis. [ABSTRACT FROM AUTHOR]

Introduction: In the fragrance and perfume industry, the controlled release of fragrances are crucial factors that contribute to consumer appeal and product quality enhancement. In this study, various aromatic active substances were extracted from dandelion root (DR), which was subsequently calcined to produce high-performance porous biochar material. Methods: The dandelion root biochar (DRB) material was identified as promising adsorbents for the controlled release of fragrances. Furfuryl alcohol was chosen as the model fragrance for inclusion and controlled release studies. Results and discussion: The DRB exhibited a substantial specific surface area of 991.89 m2/g, facilitating efficient storage and controlled release capabilities. Additionally, the DRB's high stability and porous nature facilitated rapid collection and efficient recyclability. This research significantly contributes to the development of a sustainable, zero-waste multistage utilization strategy for dandelion roots, indicating a potential applications in the food flavoring industry and environmental conservations. [ABSTRACT FROM AUTHOR]

Laccase (LAC), a copper-containing polyphenol oxidase, is an important pathogenic factor of pathogenic fungi, and has been identified as an important virulence factor in numerous pathogenic fungi. LAC is encoded by a gene family and belongs to the class of multicopper oxidases. The study aimed to identify the LAC genes in Athelia bombacina (Link) Pers, and their interactions with the host. The expression levels of the LAC genes were quantified using RT-qPCR. The LAC activity, level of malondialdehyde (MDA) and activities of protective enzymes in 'Huangguan' pears during the interaction were measured. The AbLac4 gene deletion mutant strain was constructed. Six LAC genes were identified in A. bombacina, distributed across three chromosomes. Interspecies collinearity analysis suggested that LAC genes could serve as crucial pathogenic factors in A. bombacina. The LAC gene family can be classified into three distinct subgroups. Among the subgroups, variations were observed in their characteristic sequences and conserved motifs. However, the LAC genes within the same subgroup exhibited a high degree of conservation. The genes showed diverse expression profiles, with their promoters harboring multiple stress-responsive elements. Signal peptide prediction showed that all LAC proteins, with the exception of the AbLac3 protein, possessed signal peptides, indicating that they are secretory proteins. The subcellular localization analysis showed that all LAC proteins may be localized extracellularly. RT-qPCR revealed differential expression patterns among LAC genes; specifically, AbLac1 and AbLac4 exhibited distinct expression dynamics during the infection process. The LAC activity first increased and then decreased, with the highest increase rate occurring in the early stage of culture. The MDA content and catalase (CAT) activity at the inoculated site were found to be significantly higher than the uninoculated control. In addition, the deletion of AbLac4 gene reduced the growth rate and pathogenic ability of A. bombacina. This investigation found that AbLac1 and AbLac4 may play pivotal roles in mediating host interactions, and the fruit may combat pathogen infection through increasing the activities of CAT, phenylalanine ammonia lyase and peroxidase. This study provides valuable new insights into the pathogenic mechanisms of A. bombacina, significantly contributing to the field. [ABSTRACT FROM AUTHOR]