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arXiv 2025年

作者： Chen, xuwen Shen, Shunlin zhang, Zhifei Department of Mathematics University of Rochester RochesterNY14627 United States School of Mathematical Sciences University of Science and Technology of China Hefei230026 China School of Mathematical Sciences Peking University Beijing100871 China

We broaden the application of the l2-decoupling theorem to the Boltzmann equation. We prove full-range Strichartz estimates for the linear problem in the Td setting. We establish space-time bilinear estimates, and hence the unconditional uniqueness of solutions to the Rd and Td Boltzmann equation for the Maxwellian particle and soft potential with an angular cutoff, adopting a unified hierarchy scheme originally developed for the nonlinear Schrödinger equation. Copyright © 2025, The Authors. All rights reserved.

关键词： Boltzmann equation

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Acute Effects of Different Electroacupuncture Point Combinations to Modulate the Gut-Brain Axis in the Minipig Model

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EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022年第1期2022卷 4384693页

作者： zhang, xuwen Guerin, Sylvie Launay, Youenn Serrand, Yann Coquery, Nicolas Val-Laillet, David Guangzhou Univ Chinese Med Guangzhou Peoples R China Guangzhou Rui Xingtang Chinese Med Clin Guangzhou Peoples R China Univ Rennes INRAE INSERM Nutr Metabolisms & CancNuMeCan Rennes France

This study aimed to compare the gut-brain axis responses to acute electroacupuncture (EA) at different acupoint combinations in the minipig model. Four adult Yucatan minipigs were subjected twice to four acute EA treatments (25-minute acute sessions) including sham (false acupoints) and control (no EA), during anesthesia and according to a Latin-square design paradigm. Acupoint combinations (4 loci each) are head-abdomen (#70 Dafengmen, #35 Sanwan), back (bilateral #27 Pishu, #28 Weishu), leg (bilateral #79 Hangou, #63 Housanli), and sham (2 bilateral points that are not acupoints). Electrocardiograms were performed to explore heart rate variability (HRV). Infrared thermography was used to measure skin temperature at the stimulation points. Saliva (cortisol) and blood samples (leptin, total/active ghrelin, insulin, and glucose) were collected for further analyses before and after acute EA. All animals were also subjected to BOLD fMRI to investigate the brain responses to EA. Acute EA significantly modulated several physiological and metabolic parameters compared to basal, sham, and/or control conditions, with contrasting effects in terms of BOLD responses in brain regions involved in the hedonic and cognitive control of food intake. The head-abdomen combination appeared to be the most promising combination in terms of brain modulation of the corticostriatal circuit, with upregulation of the dorsolateral prefrontal cortex, dorsal striatum, and anterior cingulate cortex. It also induced significantly lower plasma ghrelin levels compared to sham, suggesting anorectic effects, as well as no temperature drop at the stimulation site. This study opens the way to a further preclinical trial aimed at investigating chronic EA in obese minipigs.

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吡啶抽提对不同显微组分煤结构特征的影响

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煤炭转化 2014年第2期37卷 1-5页

作者：蔺华林李克健章序文中国神华煤制油化工有限公司上海研究院上海博士高级工程师201108

对神东上湾煤(SDR)及由其岩相分离得到的镜质组富集物(SDV)和惰质组富集物(SDI)进行了吡啶抽提,得到不同煤样的抽提率,并对抽提前后的煤样进行了13C-NMR,FTIR和XRD分析表征.结果表明,三种煤样的抽提率(质量分数)顺序为:镜质组富集物(15.... 详细信息

对神东上湾煤(SDR)及由其岩相分离得到的镜质组富集物(SDV)和惰质组富集物(SDI)进行了吡啶抽提,得到不同煤样的抽提率,并对抽提前后的煤样进行了13C-NMR,FTIR和XRD分析表征.结果表明,三种煤样的抽提率(质量分数)顺序为:镜质组富集物(15.78%)>上湾煤(13.89%)>惰质组富集物(9.45%);通过对吡啶抽提前后煤样的13C-NMR,FTIR和XRD的分析表明,吡啶抽提后三种煤样的芳香度均有所增加,抽提前后煤样的骨架结构没有发生大的变化.

关键词：煤结构吡啶抽提镜质组富集物惰质组富集物 13C-NMR

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科技自立自强背景下的大学适应性行为

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高教发展与评估 2022年第4期38卷 30-39,I0003,I0004页

作者：迟景明张旭雯何声升大连理工大学高等教育研究院辽宁大连116024

大学提升自身适应能力是科技自立自强背景下国家和社会对大学的必然要求。基于大学在适应外部创新生态系统情境中的现状,其适应性行为即为与企业创新主体间的相互适应、协同进化、彼此赋能过程。适应性行为不仅能够使大学获得自身生存... 详细信息

大学提升自身适应能力是科技自立自强背景下国家和社会对大学的必然要求。基于大学在适应外部创新生态系统情境中的现状,其适应性行为即为与企业创新主体间的相互适应、协同进化、彼此赋能过程。适应性行为不仅能够使大学获得自身生存发展所需的资源,而且能够带来校企间创新要素的融合与创新资源的涌流。通过引入协同进化思想与CAS理论,可从搜寻、选择、变异三段过程分析大学适应性行为:搜寻过程包括环境信息获取、自身信息审视、合作伙伴搜求三类行为;选择过程包括合作伙伴筛选、双方资源组合及组织规则选取三类行为;变异过程包含着协同体的生成发展、资源的融合重构、组织规则更新迭代三类行为。通过大学适应性行为,大学自身更加适应外部环境并与企业协同进化,助力创新生态系统的良性运转。

关键词：创新生态系统大学发展适应性行为协同进化 CAS理论

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Direct Arylation Polycondensation-Derived Polythiophene Achieves Over 16% Efficiency in Binary Organic Solar Cells via Tuning Aggregation and Miscibility

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ADVANCED ENERGY MATERIALS 2024年第47期14卷

作者： zhang, xuwen zhang, Tao Liang, Ziqi Shi, Yibo Li, Saimeng Xu, Chenhui Li, Miaomiao Ye, Long Hou, Jianhui Geng, Yanhou Tianjin Univ Sch Mat Sci & Engn Tianjin Key Lab Mol Optoelect SciKey Lab Organ In Minist EducCollaborat Innovat Ctr Chem Sci & Engn Tianjin 300350 Peoples R China Chinese Acad Sci Inst Chem CAS Res Educ Ctr Excellence Mol Sci State Key Lab Polymer Phys & ChemBeijing Natl Lab Beijing 100190 Peoples R China

Polythiophenes are the most appealing donor materials in organic solar cells (OSCs) due to their simple chemical structures. However, the top-performance polythiophenes are typically synthesized via Stille polycondensation, which is problematic due to significant toxicity and poor atom economy. By contrast, direct arylation polycondensation (DArP) is an eco-friendly, and atom-efficient alternative for synthesizing conjugated polymers, while the best efficiency for DArP-derived polythiophenes is below 12%. This study reports a series of polythiophene-based donors synthesized via DArP. Among these, PT4F-Th reaches a power conversion efficiency (PCE) of 16.4%, which not only matches the current record for polythiophene-based donor materials, but also marks the highest PCE achieved by DArP-derived donors to date. The superior performance of PT4F-Th is largely attributed to its optimal temperature-dependent aggregation behavior and moderate miscibility with acceptors, along with the highest crystallinity among the candidates, resulting in the most favorable blend film morphology. This study underscores the significant potential of DArP-derived polythiophenes in developing high-performance and eco-friendly OSCs. A series of polythiophene-based donors are synthesized using direct arylation polycondensation (DArP), highlighting PT4F-Th, which achieves an outstanding power conversion efficiency (PCE) of 16.4% in binary organic solar cells (OSCs). This efficiency sets a new record for DArP-derived donors. Blend film morphology is characterized by X-ray scattering and microscopy, emphasizing the synergistic effects of temperature-dependent aggregation behavior and miscibility. image

关键词： direct arylation polycondensation miscibility organic solar cells polythiophene power conversion efficiency

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煤直接液化柴油加氢制备轻质白油研究

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石油炼制与化工 2018年第10期49卷 43-47页

作者：单贤根舒歌平章序文曹雪萍中国神华煤制油化工有限公司上海研究院煤直接液化国家重点工程实验室上海201108

为制备轻质白油,采用贵金属加氢催化剂在30mL连续加氢实验装置上对煤直接液化柴油进行了深度加氢实验,考察了不同反应压力(6~12MPa)、反应温度(80~240℃)、体积空速(0.6~1.2h-1)条件下煤直接液化柴油的芳烃饱和行为。研究结果表明,加氢... 详细信息

为制备轻质白油,采用贵金属加氢催化剂在30mL连续加氢实验装置上对煤直接液化柴油进行了深度加氢实验,考察了不同反应压力(6~12MPa)、反应温度(80~240℃)、体积空速(0.6~1.2h-1)条件下煤直接液化柴油的芳烃饱和行为。研究结果表明,加氢后的柴油馏程、黏度、密度等性质无明显变化,但芳烃含量大幅度下降,在合适的加氢条件下产品油中芳烃质量分数可以降低至0.01%以下,满足环保型轻质白油标准要求。通过蒸馏切割发现,煤直接液化柴油所生产的轻质白油牌号主要集中在W2-40~W2-90之间。

关键词：煤直接液化柴油加氢轻质白油

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Crystalline 1D Linear Conjugated Polymers with a Quinoidal Unit As Metal-Free Electrocatalysts for Oxygen Reduction

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ADVANCED ENERGY MATERIALS 2024年第44期14卷

作者： Fan, Renzhen Wang, Cheng zhang, Xiaofei zhang, xuwen Dong, Weijia Xu, Yiyang Xu, Chenhui Chi, Chunyan Zhu, Jun Deng, Yunfeng Geng, Yanhou Tianjin Univ Joint Sch Natl Univ Singapore & Tianjin Univ Int Campus Binhai New City 350207 Fuzhou Peoples R China Tianjin Univ Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Tianjin Key Lab Mol Optoelect Sci Tianjin 300072 Peoples R China Collaborat Innovat Ctr Chem Sci & Engn Tianjin Tianjin 300072 Peoples R China Agcy Sci Tech & Res A STAR Inst Mat Res & Engn IMRE 2 Fusionopolis Way Singapore 138634 Singapore Natl Univ Singapore Dept Chem 3 Sci Dr 3 Singapore 117543 Singapore

Crystalline and soluble 1D linear conjugated polymers (LCPs) have garnered considerable interest as cost-effective and efficient metal-free electrocatalysts for the oxygen reduction reaction (ORR) due to their high exposure of catalytic sites and ease of processing. However, difficulties remain in achieving excellent ORR performance for 1D LCPs by conventional molecular design. Herein, it is demonstrated the utilization of quinoidal units as a promising strategy to develop 1D LCPs for ORR. The incorporation of quinoidal unit not only results in polymers with strong inter- and intra-molecular interactions and low-lying LUMO (lowest unoccupied molecular orbital) energy levels, but also provides polymers with good crystallinity and commendable charge carrier mobilities. The electronic properties of these polymers are fine-tuned through the introduction of additional heteroatoms and/or substituents in the monomers and comonomers to understand and optimize their ORR catalytic activity. Evaluation of their catalytic performances reveals a remarkable half-wave potential and limiting current density of up to 0.74 V (vs reversible hydrogen electrod) and 7.50 mA cm-2, respectively. Notably, these performances are achieved without the addition of carbon nanomaterials as support. This study offers a new insight into the design of highly efficient metal-free organic electrocatalysts. 1D linear conjugated polymers containing a quinoidal unit are synthesized as the metal-free electrocatalysts for oxygen reduction reaction. These polymers show good film-forming properties, well-ordered structures, and excellent charge transport abilities. As a result, they exhibit high oxygen reduction reaction catalytic activities without the need for carbon nanomaterials as support. image

关键词： conjugated polymers energy conversion metal-free oxygen reduction reaction quinoidal compounds

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Neutrophil-lymphocyte ratio: a correlation study of its effect on magnetic resonance imaging enhancement patterns in spinal parenchymal tuberculosis

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BMC INFECTIOUS DISEASES 2025年第1期25卷 1-9页

作者： Shan, Qiulan zhang, Le Fu, xuwen Qi, Min Wei, Jialu Gan, Wei Pu, Ying Shen, Lingjun Li, Xiang Kunming Third Peoples Hosp Yunnan Clin Med Ctr Infect Dis Dept Radiol 319 Wujing Rd Kunming 650041 Yunnan Peoples R China Kunming Third Peoples Hosp Yunnan Clin Med Ctr Infect Dis Dept ICU Kunming 650041 Yunnan Peoples R China Kunming Third Peoples Hosp Yunnan Clin Med Ctr Infect Dis Dept Pharm Kunming 650041 Peoples R China Kunming Third Peoples Hosp Yunnan Clin Med Ctr Infect Dis Dept TB 319 Wujing Rd Kunming 650041 Yunnan Peoples R China

Objective To explore the impact of the neutrophil-lymphocyte ratio (NLR) on magnetic resonance imaging (MRI) enhancement patterns in patients with spinal parenchymal tuberculosis. Methods In this study, a retrospective analysis was conducted on 42 patients diagnosed for the first time with spinal parenchymal tuberculosis at Kunming Third People's Hospital between 2019 and 2024. They were divided into a homogeneous enhancement group and a ring enhancement group based on MRI characteristics and an analysis of their clinical presentations, imaging features and laboratory test results. Results A total of 42 patients were included in the study, with 30 in the ring enhancement group and 12 in the homogeneous enhancement group. The ring enhancement group exhibited a significantly higher proportion of fever, night sweats and limb sensory/motor dysfunction compared with the homogeneous enhancement group (p < 0.05). For laboratory tests, the ring enhancement group showed remarkably elevated peripheral blood neutrophil counts and NLR, along with markedly reduced lymphocyte counts and proportions (p < 0.05). Additionally, the incidence of perilesional oedema was substantially higher in the ring enhancement group than in the homogeneous enhancement group (p < 0.05). Conclusion The NLR may serve as a potential indicator for assessing MRI enhancement patterns in spinal parenchymal tuberculosis, which is beneficial for identifying patients at different pathological stages of the disease. This study provides novel perspectives for clinical diagnosis and treatment while emphasising the need for further research on the application value of the NLR in tuberculosis.

关键词： Spinal parenchymal tuberculosis Neutrophil-lymphocyte ratio Magnetic resonance imaging enhancement patterns Tuberculosis

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Nomogram to screen older adult patients attending the radiology department for sarcopenia

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BMC GERIATRICS 2025年第1期25卷 1-9页

作者： Yuan, Guiying Ye, Guoxi Hu, Jianguang Hu, Huimin Shi, Chanmei zhang, Ye Huang, Junbing Li, Zhiqiong Zeng, xuwen Tan, Rongshao Xiong, Yuchao Jinan Univ Guangzhou Red Cross Hosp Dept Resp Guangzhou Peoples R China Jinan Univ Guangzhou Red Cross Hosp Dept Radiol 396 Tongfu Rd Guangzhou Guangzhou 510220 Guangdong Provi Peoples R China Jinan Univ Guangzhou Red Cross Hosp Dept Nephrol Guangzhou Peoples R China Jinan Univ Guangzhou Red Cross Hosp Inst Dis Oriented Nutr Res Dept Clin Nutr Guangzhou Peoples R China

BackgroundSarcopenia is an age-related syndrome that can impact the physical and mental health of older adults. However, it is often overlooked in clinical practice. Therefore, we aim to construct a nomogram based on simplified discriminant parameters for screening older adult patients for sarcopenia *** cross-sectional study included 654 patients aged >= 60 years who underwent an examination in the radiology department between October 2023 and June 2024. Patients were diagnosed with sarcopenia according to the method and cutoff value criteria proposed the Asian Working Group on Sarcopenia (AWGS) 2019 criteria. Calf circumference (CC), SARC-F score, mid-upper arm circumference (MUAC), and SARC-CalF score were used as simplified discriminant parameters for sarcopenia. The discriminative ability of these parameters for sarcopenia was assessed using receiver operating characteristic analysis. Additionally, we included each screening parameter and evaluated it's important for screening for the presence of sarcopenia via univariate and multivariate logistic regression analysis to develop a new screening nomogram model. The performance of the nomogram was evaluated using receiver operating characteristic curves, and the performance of the nomogram model was compared to that of CC, SARC-F, MUAC, and the SARC-CalF using the Delong *** the 654 subjects, 120 (18.3%) were diagnosed with sarcopenia, and the areas under the curve (AUCs) of the CC, SARC-F, MUAC, and SARC-CalF were 0.73, 0.61, 0.66, and 0.70, respectively. The multivariate analysis results revealed that older age, male sex, low CC, low MUAC, and low strength were related to sarcopenia. A nomogram model constructed with these five variables had an AUC of 0.84. The DeLong test showed that the diagnostic efficacy of the joint model was significantly higher than that of CC, SARC-F, MUAC, and *** simple nomogram based on simplified discriminant parameters offers personalized

关键词： Sarcopenia Nomogram Calf circumference SARC-F SARC-CalF

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A synergistic water-saving strategy combining stage-specific irrigation and application of exogenous thiamine enhances drought resistance of Xinjiang cotton

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PLANT AND SOIL 2025年 1-14页

作者： Zhao, Fuxiang Xia, Linjie Sun, Simin Li, Hang Rong, Yuxuan Wang, Yuxin Wang, xuwen Kong, Xianhui Zhu, Longfu zhang, Xianlong Yu, Yu Yang, Xiyan Xinjiang Acad Agr & Reclamat Sci Cotton Inst Shihezi 832000 Xinjiang Peoples R China Huazhong Agr Univ Natl Key Lab Crop Genet Improvement Wuhan 430070 Hubei Peoples R China Hubei Hongshan Lab Wuhan Peoples R China

Background and aimsXinjiang is the largest cotton planting area in China. However, the perennial water shortage in Xinjiang restricts the development of the cotton industry, making drought one of the important limiting factors. The aim of this study was to evaluate the effectiveness of water-saving scheme and thiamine (Thi) application on alleviating the adverse effects of drought stress on the growth and development of *** this study, five Xinjiang-released cotton varieties (Jinken1775, Jinken1565, Huamian702, Zhongmian979, and Jinfeng2) were selected as the research object, and Xinluzao8 served as the drought-sensitive control. Comprehensive drought resistance index (D) of the drought resistance coefficient (DRC) of four yield and four quality traits were used to evaluate the drought resistant ability of the six cotton varieties under different water conditions and Thi spraying *** stage-specific irrigation strategy (60% during vegetative vs. 90% during the flowering and boll stage) concurrently maintained higher drought resistance across cultivars, with Jinken1565 exhibited the highest drought resistance. This scheme reduced irrigation by 26% while sustaining fiber quality. Exogenous 50 mM Thi further enhanced drought tolerance, reducing transpiration rate by 33% and blade damage by 55%. These results demonstrate that stage-specific water management optimizes drought adaptation in cotton cultivation under drought *** study suggests that a 26% water-saving scheme was proposed for most drought-resistant varieties planted in Xinjiang, and an appropriate scheme to achieve stable yield by Thi application during the early drought condition was proposed for varieties with low drought resistant ability.

关键词： Cotton Drought resistance Comprehensive drought resistance index Thiamine Water saving scheme

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