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A synthesis of the Cretaceous wildfire record related to atmospheric oxygen levels?

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Journal of Palaeogeography 2024年第1期13卷 149-164页

作者： Da-Wei Lü Wen-xu Du Zhi-Hui Zhang Yuan Gao Tian-Tian wang Jin-Cheng xu ao-Cong Zhang Cheng-Shan wang Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina School of Earth Sciences and Resources China University of GeosciencesBejing 100083China Institute of Earth Sciences China University of Geosciences(Bejing)Beijing 100083China

The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. In this study, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). Spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the Early Cretaceous to the Late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.

关键词： Wildfire Cretaceous Atmospheric oxygen Taphonomy Charcoal

Low-viscosity oligoether esters(OEEs)as high-efficiency lubricating oils:Insight on their structure‒lubricity relationship

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Friction 2024年第6期12卷 1133-1153页

作者： Hanwen wang Ying wang Ping WEN lin MA Mingjin FAN Rui DONG Chunhua ZHANG Shaanxi Key Laboratory of Phytochemistry College of Chemistry&Chemical EngineeringBaoji University of Arts and SciencesBaoji 721013China Key Laboratory of Shaanxi Province for Development and Application of New Transportation Energy Chang’an UniversityXi’an 710064China

Development of energy-efficient lubricants is a way to reduce energy consumption for transportation,with the tendency to design molecules that are beneficial in reducing the viscosity of synthetic *** esters(OEEs),as a low-viscosity ester base oil,have characteristics such as simple synthesis and excellent lubrication effect;however,the application of OEEs in tribology field has rarely been *** objective of the present study is to investigate the effect of structure on the lubricating performance of OEEs and to develop a predictive model for OEEs based on quantitative structure‒property relationship(QSPR)through a combination of experiment and statistical *** showed that glycol chains contribute positively to lubrication with the ether functional groups increasing the sites of *** to branched-chain OEEs,straight-chain OEEs exhibited reduced wear,which was mainly due to the thicker adsorption film formed by the straight-chain ***,carbon films were detected on lightly worn surfaces,indicating that OEEs underwent oxidation during the friction *** on the results of principal component analysis(PCA)and partial least squares(PLS),it could be found that the predictive models of viscosity‒temperature performance,thermal stability performance,coefficient of friction(COF),and wear volume(WV)performed well and *** them,COF and WV can be best predicted with an R^(2) of about 0.90.

关键词： oligoether esters(OEEs) low-viscosity ester friction wear quantitative structure-property relationship(QSPR)

Analysis of sensitivity to hydrate blockage risk in natural gas gathering pipeline

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Petroleum Science 2024年第4期21卷 2723-2733页

作者： ao-Yang Zhang Meng Cai Na Wei Hai-Tao Li Chao Zhang Jun Pei xin-Wei wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Research Institute of Production Engineering Daqing Oilfield Co.Ltd.

During the operational process of natural gas gathering and transmission pipelines, the formation of hydrates is highly probable, leading to uncontrolled movement and aggregation of hydrates. The continuous migration and accumulation of hydrates further contribute to the obstruction of natural gas pipelines, resulting in production reduction, shutdowns, and pressure build-ups. Consequently, a cascade of risks is prone to occur. To address this issue, this study focuses on the operational process of natural gas gathering and transmission pipelines, where a comprehensive framework is established. This framework includes theoretical models for pipeline temperature distribution, pipeline pressure distribution, multiphase flow within the pipeline, hydrate blockage, and numerical solution methods. By analyzing the influence of inlet temperature, inlet pressure, and terminal pressure on hydrate formation within the pipeline, the sensitivity patterns of hydrate blockage risks are derived. The research indicates that reducing inlet pressure and terminal pressure could lead to a decreased maximum hydrate formation rate, potentially mitigating pipeline blockage during natural gas transportation. Furthermore, an increase in inlet temperature and terminal pressure, and a decrease in inlet pressure, results in a displacement of the most probable location for hydrate blockage towards the terminal station. However,it is crucial to note that operating under low-pressure conditions significantly elevates energy consumption within the gathering system, contradicting the operational goal of energy efficiency and reduction of energy consumption. Consequently, for high-pressure gathering pipelines, measures such as raising the inlet temperature or employing inhibitors, electrical heat tracing, and thermal insulation should be adopted to prevent hydrate formation during natural gas transportation. Moreover, considering abnormal conditions such as gas well production and pipeline network s

关键词： Natural gas hydrates Gathering pipeline Temperature variation Hydrate formation rate Sensitivity analysis

Knockout of C6orf120 in Rats Alleviates Concanavalin A-induced Autoimmune Hepatitis by Regulating Macrophage Polarization

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Biomedical and Environmental Sciences 2024年第6期37卷 594-606页

作者： xin wang Yuqi wang Hui Liu Yingying lin Peng wang Yunyun Yi xin Li Department of Center of Integrated Traditional Chinese and Western Medicine Peking University Ditan Teaching HospitalBeijing 100015China Department of Center of Integrated Traditional Chinese and Western Medicine Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Department of Center of Infectious Disease Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China

Objective The effect of the functionally unknown gene C6orf120 on autoimmune hepatitis was investigated on C6orf120 knockout rats(C6orf120^(-/-))and THP-1 *** Six–eight-week-old C6orf120^(-/-)and wild-type(WT)SD rats were injected with Con A(16 mg/kg),and euthanized after 24 *** sera,livers,and spleens were ***-1 cells and the recombinant protein(rC6ORF120)were used to explore the mechanism in *** frequency of M1 and M2 macrophages was analyzed using flow *** blotting and PCR were used to detect macrophage polarization-associated *** C6orf120 knockout attenuated Con A-induced autoimmune *** cytometry indicated that the proportion of CD68^(+)CD86^(+)M1 macrophages from the liver and spleen in the C6orf120^(-/-)rats decreased.C6orf120 knockout induced downregulation of CD86 protein and the mRNA levels of related inflammatory factors TNF-α,IL-1β,and IL-6 in the liver.C6orf120 knockout did not affect the polarization of THP-1 ***,rC6ORF120 promoted the THP-1 cells toward CD68^(+)CD80^(+)M1 macrophages and inhibited the CD68^(+)CD206^(+)M2 *** C6orf120 knockout alleviates Con A-induced autoimmune hepatitis by inhibiting macrophage polarization toward M1 macrophages and reducing the expression of related inflammatory factors in C6orf120^(-/-)rats.

关键词： C6orf120 Autoimmune hepatitis Macrophage polarization M1 macrophages

Progress in systematics and biogeography of Orchidaceae

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Plant Diversity 2024年第4期46卷 425-434页

作者： Yajun wang Hanchen wang Chao Ye Zhiping wang Chongbo Ma Dongliang lin x.aohua Jin State Key Laboratory of Plant Diversity and Specialty Crops Institute of Botanythe Chinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100093China China National Botanical Garden Beijing 100093China

Orchidaceae are one of the largest families of angiosperms in terms of species *** the last decade,numerous studies have delved into reconstructing the phylogenetic framework of Orchidaceae,leveraging data from plastid,mitochondrial and nuclear *** studies have provided new insights into the systematics,diversification and biogeography of Orchidaceae,establishing a robust foundation for future ***,pronounced controversies persist regarding the precise placement of certain lineages within these phylogenetic *** address these discrepancies and deepen our understanding of the phylogenetic structure of Orchidaceae,we provide a comprehensive overview and analysis of phylogenetic studies focusing on contentious groups within Orchidaceae since 2015,delving into discussions on the underlying reasons for observed topological *** also provide a novel phylogenetic framework at the subtribal ***,we examine the tempo and mode underlying orchid species diversity from the perspective of historical biogeography,highlighting factors contributing to extensive ***,we delineate avenues for future research aimed at enhancing our understanding of Orchidaceae phylogeny and diversity.

关键词： Diversification Orchid phylogenetics Phylogenetic conflicts Biogeography Taxonomy

Insights into sensitizing and eliciting capacity of gastric and gastrointestinal digestion products of shrimp(Penaeus vannamei)proteins in BALB/c mice

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Food Science and Human Wellness 2024年第1期13卷 339-348页

作者： Yao Liu Songyi lin Kexin Liu Shan wang wang Li Na Sun National Engineering Research Center of Seafood School of Food Science and TechnologyDalian Polytechnic UniversityDalian 116034China Collaborative Innovation Center of Seafood Deep Processing Dalian Polytechnic UniversityDalian 116034China

Shrimp(Penaeus vannamei)proteins have been shown an allergenic potential;however,little information is available on the sensitizing and eliciting capacity of shrimp protein digestion *** this study,a BALB/c mice model was used to explore the allergenicity of shrimp protein sample(SPS)and their gastric and gastrointestinal digestion products(GDS/GIDS).As compared with the SPS groups,the GDS/GIDS groups caused lower specific immunoglobulins(Ig E/Ig G1)levels(Px,mouse mast cell protease-1(m MCP-1)concentration and proportion of degranulated mast cells were significantly reduced in the GDS/GIDS groups(P<0.05);simultaneously,allergic symptoms,vascular permeability and histopathological changes of tissues were ***,the allergenicity of digestion products cannot be eliminated and still cause systemic allergic reactions in *** study showed that the digestion products of shrimp still had high sensitizing and eliciting capacity.

关键词： Penaeus vannamei Allergenicity Digestion BALB/c mice model

A surgical alternative of fusiform penetrating keratoplasty for the management of severe infectious keratitis

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1431-1436页

作者： x.ao-lin Qi Li-Chao wang Miao-lin wang Hua Gao Eye Hospital of Shandong First Medical University State Key Laboratory Cultivation BaseShandong Provincial Key Laboratory of OphthalmologyShandong Eye InstituteShandong First Medical University&Shandong Academy of Medical SciencesJinan 250021Shandong ProvinceChina

AIM:To describe the surgical procedure of fusiform penetrating keratoplasty(FPK)using multiple trephines of different sizes for treating patients with severe infectious ***:Fourteen eyes underwent FPK,and 15 eyes received conventional penetrating keratoplasty(PK)were included in the *** best-corrected visual acuity(BCVA),refractive outcomes,endothelial cell density,and postoperative complications were ***:The FPK group was followed for an average of 15.3±2.1mo,whereas the PK group was followed for 16.1±*** corneal ulcers were elliptical-shaped in all 14 eyes in the FPK *** mean BCVA(logMAR,0.26±0.13)showed no statistically significant differences from that in the PK group(logMAR,0.21±0.12,P>0.05)at 1y after *** the mean curvature,mean astigmatism,and mean spherical equivalent in the FPK group were lower than those in the PK group(Paocular pressure was observed in the two ***:For patients with elliptical-shaped corneas or corneal ulcers,FPK can avoid disrupting of corneal limbus,reduce the risk of postoperative complications,and can result in satisfactory visual quality.

关键词： fusiform penetrating keratoplasty multiple trephines infectious keratitis cornea

ConvNext-UperNet-Based Deep Learning Model for Road Extraction from High-Resolution Remote Sensing Images

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Computers, Materials & Continua 2024年第8期80卷 1907-1925页

作者： Jing wang Chen Zhang Tianwen lin Geographic Information and Tourism College Chuzhou UniversityChuzhou239000China Anhui Province Key Laboratory of Physical Geographic Environment Chuzhou UniversityChuzhou239000China

When existing deep learning models are used for road extraction tasks from high-resolution images,they are easily affected by noise factors such as tree and building occlusion and complex backgrounds,resulting in incomplete road extraction and low *** propose the introduction of spatial and channel attention modules to the convolutional neural network ***,ConvNext is used as the backbone network,which cooperates with the perceptual analysis network UPerNet,retains the detection head of the semantic segmentation,and builds a new model ConvNext-UPerNet to suppress noise *** on the open-source DeepGlobe and CHN6-CUG datasets and introducing the DiceLoss on the basis of CrossEntropyLoss solves the problem of positive and negative sample *** results show that the new network model can achieve the following performance on the DeepGlobe dataset:79.40%for precision(Pre),97.93% for accuracy(Acc),69.28% for intersection over union(IoU),and 83.56% for mean intersection over union(MIoU).On the CHN6-CUG dataset,the model achieves the respective values of 78.17%for Pre,97.63%for Acc,65.4% for IoU,and 81.46% for *** with other network models,the fused ConvNext-UPerNet model can extract road information better when faced with the influence of noise contained in high-resolution remote sensing *** also achieves multiscale image feature information with unified perception,ultimately improving the generalization ability of deep learning technology in extracting complex roads from high-resolution remote sensing images.

关键词： Deep learning semantic segmentation remote sensing imagery road extraction

Nanoparticle delivery for central nervous system diseases and its clinical application

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Nano Research 2024年第7期17卷 6305-6322页

作者： lin Tang Rui Zhang Yusi wang Mohan Liu Die Hu Yuanda wang Li Yang Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China

In the treatment of central nervous system(CNS)diseases such as glioma,Alzheimer's disease(AD)and Parkinson's disease(PD),drugs are expected to reach specific areas of the brain to achieve the desired *** a growing number of therapeutic targets have been identified in preclinical studies,the ones that can ultimately be used in the clinic are ***,the research process and clinical application of drugs for treating CNS diseases are still large *** barriers such as the blood‒brain barrier(BBB)act as selective permeable membranes,allowing only certain molecules to enter the brain;this barrier is the major obstacle restricting the arrival of most drugs to brain ***,nanoparticles,including lipid-based,cell-derived biomimetic,polymeric and inorganic nanoparticles,have gained increasing attention because of their ability to cross physiological barriers,and could play an important role as delivery carriers and ***,clinical applications of nanoparticles in CNS diseases are *** review focuses on the progress of current research on the use of nanoparticles for the treatment of CNS diseases to provide additional insight into the treatment of CNS diseases.

关键词： nanoparticles central nervous system(CNS)diseases clinical applications delivery carriers immunomodulators