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Characteristics and Sources of Organic Aerosol in PM 2.5 at Yangbajing in Tibetan Plateau

ATMOSPHERIC ENVIRONMENT 2024年 333卷

作者： Xiang, Yaxin li, xuwen Zhang, Tianle Cheng, Qian Yan, Caiqing liu, Xiaomeng liu, Yue Wang, Yinan Kang, Shichang Ding, Xiang Zheng, Mei Peking Univ Coll Environm Sci & Engn SKL ESPC Beijing 100871 Peoples R China Peking Univ Ctr Environm & Hlth Beijing 100871 Peoples R China Chinese Acad Sci Guangzhou Inst Geochem State Key Lab Organ Geochem Guangzhou 510640 Peoples R China Chinese Acad Sci Guangzhou Inst Geochem Guangdong Prov Key Lab Environm Protect & Resource Guangzhou 510640 Peoples R China Chinese Acad Sci Guangzhou Inst Geochem Guangdong Hong Kong Macao Joint Lab Environm Pollu Guangzhou 510640 Peoples R China Shandong Univ Environm Res Inst Qingdao 266237 Peoples R China Natl Inst Metrol China Ctr Environm Metrol Beijing 100029 Peoples R China Chinese Acad Sci Inst Atmospher Phys Key Lab Middle Atmosphere & Global Environm Observ Beijing 100029 Peoples R China Chinese Acad Sci Northwest Inst Ecoenvironm & Resources State Key Lab Cryospher Sci Lanzhou 730000 Peoples R China Peking Univ Coll Environm Sci & Engn Beijing 100871 Peoples R China Chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510640 Peoples R China

The climate and environment of the Tibetan Plateau (TP) are sensitive to human activities. As a key component highly influencing global climate and environment, organic aerosol over the TP is investigated in this study, especially in organic composition and its sources. This study aims to explore the composition characteristics, seasonal variation, and potential sources of organic aerosol including two episodes through one-year sampling at the Yangbajing (YBJ) site in the TP. A total of 120 primary and secondary organic species as well as organic carbon (OC) and elemental carbon (EC) were measured in PM2.5. The annual average concentrations of OC, EC, and organic species were 3.12 +/- 3.73 mu gC/m3, 0.28 +/- 0.18 mu gC/m3 and 104 +/- 36.6 ng/m3, respectively. High ratio of OC to EC (OC/EC) and low ratio of fatty acids to n-alkanes were found for aerosol in the TP. The OC/EC ratio was 11.8 +/- 10.2 on average at the YBJ site and strongly correlated with levoglucosan, a tracer for biomass burning, but not so with typical secondary species, indicating that the high ratio of OC/EC over the TP was more influenced by biomass burning than secondary formation. The ratio of fatty acids to n-alkanes at YBJ was 1.39 +/- 0.29 on average, lower than those reported over urban areas (3.13 +/- 1.49), probably owing to less residential cooking activities. Seasonally, the non-monsoon season had significant increases in primary organic aerosol (POA) tracers, among which biomass burning tracers had a higher increase percentage than other specific tracers. On the contrary, the levels of secondary organic aerosol (SOA) tracers, especially isoprene- and monoterpenederived SOA tracers were enhanced in the monsoon season (summer time), largely resulting from high emissions of biogenic volatile organic compounds. Two episodes characterized with much higher concentrations of organic species (1215 and 688 ng/m3) were observed in this study. One was characterized by significant enhancement of P

关键词： Organic speciation Tibetan Plateau Sources Primary organic aerosol Secondary organic aerosol

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PLA光学纯度和等温退火处理对熔喷非织造布结构与性能的影响

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印染 2025年第2期51卷 45-48页

作者：李旭文于本成王鹏王金剑陈鹏传化智联股份有限公司浙江杭州311215 中国科学院宁波材料技术与工程研究所浙江省生物基高分子材料技术与应用重点实验室宁波市高分子材料重点实验室浙江宁波315201

选用4种不同PLA原料制备熔喷非织造布,测试了纤维直径、热结晶性能、表面电压和过滤效率衰减,并将熔融指数接近但光学纯度不同的PLA原料制备的驻极非织造布进行等温退火处理,以探究结晶对非织造布力学性能的影响。结果表明:光学纯度较高... 详细信息

选用4种不同PLA原料制备熔喷非织造布,测试了纤维直径、热结晶性能、表面电压和过滤效率衰减,并将熔融指数接近但光学纯度不同的PLA原料制备的驻极非织造布进行等温退火处理,以探究结晶对非织造布力学性能的影响。结果表明:光学纯度较高的PLA原料的结晶性能要优于光学纯度低的,光学纯度对熔喷PLA驻极非织造布的纤维平均直径和过滤效率没有影响;不同光学纯度PLA原料制备的熔喷非织造布都存在表面电压和过滤效率随放置时间延长而降低的现象,其中光学纯度较高的PLA原料制备的非织造布表面电压和过滤效率的保留率较高,捕获电荷能力更强;熔喷PLA驻极非织造布的结晶度和力学性能随退火时间的延长而提高,高光学纯度原料制备的驻极非织造布的力学性能增幅最大。

关键词：光学纯度退火结晶非织造布表面电压过滤效率

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Fibrin gel-assisted stone extraction in retrograde intrarenal surgery

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BJU INTERNATIONAL 2022年第2期129卷 170-173页

作者： Yu, Yue Xi, Haibo Chen, Yujun li, xuwen liu, Wei Hu, Jieping Deng, Jun liu, Xiaoqiang lin, Longhui li, Chen Wang, Mengzhen Fu, Bin Wang, Gongxian Kuang, Renrui Zhou, Xiaochen Nanchang Univ Affiliated Hosp 1 Dept Urol Nanchang Jiangxi Peoples R China

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The Pararectus approach in acetabular fractures treatment: functional and radiologcial results

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BMC MUSCULOSKELETAL DISORDERS 2022年第1期23卷 370-370页

作者： liu, Guoming Chen, Jinli liang, Chengzhi Zhang, Chengdong li, xuwen Hu, Yanling Qingdao Univ Dept Orthoped Affiliated Hosp Qingdao 266003 Shandong Peoples R China

Background The surgical treatment of complex acetabular fractures is one of the most challenging procedures for orthopedic surgeons. The Pararectus approach, as a reasonable alternative to the existing surgical procedures, was performed for the treatment of acetabular fractures involving the anterior column. This study aimed to evaluate outcome using the Pararectus approach for acetabular fractures involving anterior columns. Methods Thirty-seven with displaced acetabular fractures involving anterior columns were treated between July 2016 and October 2019 using the Pararectus approach. The functional outcomes (using the Merle d Aubigne and Postel scoring system, WOMAC and modified Harris scoring), the quality of surgical reduction (using the Matta criteria), and postoperative complications were assessed during approximately 26 months follow-up period. Results Thirty-seven patients (mean age 53 years, range: 30-71;28 male) underwent surgery. Mean intraoperative blood loss was 840 ml (rang: 400-2000 ml) and mean operating time was 210 min (rang: 140-500 min). The modified Merle d Aubigne score was excellent and good in 27 cases (73%), fair in 6 cases (16%), and poor in 3 cases (11%). The mean score was 88.5 (range:77-96) for the modified Harris Hip scores, and 22 (range:7-35) for the WOMAC scores after operation. Postoperative functional outcomes were significantly improved compared with preoperative outcomes (P < 0.0001). The quality of reduction was anatomical in 21 cases (57%), satisfactory in 9 cases (24%), and unsatisfactory in 7 cases (19%). At follow-up, four patients developed a DVT, and heterotopic bone formation was observed in one patient. The hip osteoarthritis was not observed. Conclusion The Pararectus approach achieved good functional outcomes and anatomical reduction in the treatment of acetabular fractures involving anterior column with minimal access morbidity.

关键词： Acetabular fracture Pararectus approach Surgical exposure Outcome Radiological results

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Molecular and epidemiological characterization of Staphylococcus aureus causing bovine mastitis in China

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MICROBIAL PATHOGENESIS 2024年 191卷 106640页

作者： Zhu, lingling Lai, Yuxin li, xuwen Ma, Hui Gong, Fengju Sun, Xueqiang Cao, Aiqiao Jiang, Tao Han, Yintao Pan, Zihao Nanjing Agr Univ Coll Vet Med OIE Reference Lab Swine Streptococcosis Nanjing Peoples R China Nanjing Agr Univ Coll Vet Med Nanjing Peoples R China China Anim Hlth & Epidemiol Ctr Qingdao Peoples R China Shenzhen Ctr Anim Dis Control & Prevent Shenzhen Peoples R China Nanjing Univ Jinling Hosp Affiliated Hosp Med Sch Dept Stomatol Nanjing Peoples R China

Background: Staphylococcus aureus is one of the most prevalent pathogens in bovine mastitis, which leads to substantial financial losses for the dairy industry. Results: In this study, S. aureus (n = 72) was isolated from 18 dairy farms in 15 provinces across China in 2021. The identification of these isolates at the species level was achieved by employing 16S rRNA sequencing. An isothermal amplification method for auxiliary detection of S. aureus was established, which can be employed not only for laboratory detection but also for point-of-care testing (POCT). Molecular characteristics of S. aureus mastitis in Chinese dairy cows were determined through MLST and spa typing. Finally, methicillin-resistant Staphylococcus aureus (MRSA) and MRSA resistance genes were detected using MIC and PCR amplification techniques. 72 isolates were identified as 12 sequence types (STs) and 7 clonal complexes (CC). ST1/CC1 was the dominant prevalent accounting for 33.3 % of the total, and exhibiting a wide distribution range. In terms of spa types, t114 was the dominant type, accounting for 31.9 % of the total, followed by t529 as the second major type. Four S. aureus strains were classified as MRSA according to their levels of oxacillin resistance (MIC >= 4 mu g/mL). Among these four MRSA strains, one of them was found to be mecA positive. However, the presence of drugresistance genes mecA and mecC was not detected in the remaining three MRSA strains, indicating the possible existence of new resistance genes. Conclusions: Our study investigated the prevalence of S. aureus mastitis in dairy cows in China, while also examined the molecular characteristics and MRSA strains. This information will help with the clinical monitoring, prevention, and control of S. aureus mastitis in dairy cattle.

关键词： Staphylococcus aureus Molecular characterization MRSA MLST Spa

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Exploring the mechanism of sweetener neohesperidin dihydrochalcone on oral tolerance via a network pharmacology approach combined with vivo and vitro methods

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JOURNAL OF FUNCTIONAL FOODS 2022年第0期95卷

作者： Shi, Xiaolei Wei, Jihao Zhang, Yupu Xue, Jingwen Jin, Yongri li, xuwen Jilin Univ Coll Food Sci & Engn Changchun Peoples R China Jilin Univ Coll Chem Changchun Peoples R China JilinState Tobacco Monopoly Adm Changchun Peoples R China Jilin Univ Coll Chem 2699 Qianjin Rd Changchun 130012 Peoples R China

Neohesperidin dihydrochalcone (NHDC) is a kind of sweetener widely used in food processing. Some artificial sweeteners induce food allergy by breaking oral tolerance (OT). The relationship between NHDC and oral tolerance are important in food safety. We explored the possible effects of NHDC on OT via network pharmacology combined with vivo and vitro experiments. NHDC was predicted to have effects on OT. It was focus on immunoglobulin production, inflammation and immunity. Then, OT mouse model and mast cell degranulation were applied to further explore the mechanism. NHDC could affect the Th2 response by suppressing the sIgG1 level in the serum and GATA-3 expression in the colon. NHDC could inhibit RBL-2H3 cells degranulation by suppressing the Ca2+ influx and MAPK signaling pathways. Results showed that NHDC can be safely applied in food processing and had promotional effects on oral tolerance.

关键词： Sweetener Tolerance Food allergy Risk Mechanism Food safety

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Single-Atom Fe-Anchored Nano-Diamond With Enhanced Dual-Enzyme Mimicking Performance for H2O2 and Glutathione Detection

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FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY 2022年 9卷 790849页

作者： liu, Ying Yan, Jianghong Huang, Yu Sun, Zhiheng Zhang, Huijing Fu, lihaoyuan li, xuwen Jin, Yongri Jilin Univ Coll Chem Changchun Peoples R China First Clin Hosp Jilin Prov Acad Tradit Chinese Med Changchun Peoples R China

Glutathione (GSH) is an important antioxidant and free radical scavenger that converts harmful toxins into harmless substances and excretes them out of the body. In the present study, we successfully prepared single-atom iron oxide-nanoparticle (Fe-NP)-modified nanodiamonds (NDs) named Fe-NDs via a one-pot in situ reduction method. This nanozyme functionally mimics two major enzymes, namely, peroxidase and oxidase. Accordingly, a colorimetric sensing platform was designed to detect hydrogen peroxide (H2O2) and GSH. Owing to their peroxidase-like activity, Fe-NDs can oxidize colorless 3,3 ',5,5 '-tetramethylbenzidine (TMB) into blue with sufficient linearity at H2O2 concentrations of 1-60 mu M and with a detection limit of 0.3 mu M. Furthermore, using different concentrations of GSH, oxidized TMB can be reduced to TMB, and the color change from blue to nearly colorless can be observed by the naked eye (linear range, 1-25 mu M;detection limit, 0.072 mu M). The established colorimetric method based on oxidase-like activity can be successfully used to detect reduced GSH in tablets and injections with good selectivity and high sensitivity. The results of this study exhibited reliable consistency with the detection results obtained using high-performance liquid chromatography (HPLC). Therefore, the Fe-NDs colorimetric sensor designed in this study offers adequate accuracy and sensitivity.

关键词： nanodiamond single-atom Fe peroxidase-like and oxidase-like activity colorimetric sensor glutathione

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窄蒂鼻唇沟皮下蒂皮瓣在鼻部及鼻旁恶性肿瘤切除后创面修复中的应用

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中华解剖与临床杂志 2023年第8期28卷 527-532页

作者：李旭文葛秀玉宋培军徐静蚌埠医学院第一附属医院整形外科蚌埠233004

目的探讨窄蒂鼻唇沟皮下蒂皮瓣在鼻部及鼻旁恶性肿瘤切除术后修复面部缺损的效果。方法回顾性队列研究。纳入蚌埠医学院第一附属医院整形外科2018年6月—2022年6月收治的鼻部及鼻旁体表恶性肿瘤患者40例,其中男13例、女27例,年龄52~93(6... 详细信息

目的探讨窄蒂鼻唇沟皮下蒂皮瓣在鼻部及鼻旁恶性肿瘤切除术后修复面部缺损的效果。方法回顾性队列研究。纳入蚌埠医学院第一附属医院整形外科2018年6月—2022年6月收治的鼻部及鼻旁体表恶性肿瘤患者40例,其中男13例、女27例,年龄52~93(69±12)岁。患者均行肿瘤扩大切除术,根据肿瘤切除后创面修复方法不同分为2组:对照组20例,采用传统的局部转位皮瓣修复;观察组20例,采用窄蒂鼻唇沟皮下蒂推进皮瓣修复。观察并比较2组患者的临床基线资料,皮瓣面积、皮瓣蒂部宽度、皮瓣面积与蒂部宽度比值、手术时间、术中出血量、皮瓣存活率、供瓣区直接缝合率等围术期指标,术后6个月温哥华瘢痕量表(VSS)评分,以及术后创面感染、皮瓣下积液、创面出血、皮瓣对周围组织牵拉、蒂部“猫耳”形成等并发症发生情况。结果2组患者年龄、性别、住院时间以及肿瘤性质、大小、部位等基线资料比较,差异均无统计学意义(P值均>0.05)。观察组皮瓣面积为(6.90±1.94)cm^(2),对照组为(7.80±2.24)cm^(2),差异无统计学意义(t=1.36,P=0.182)。观察组皮瓣蒂部宽度(0.98±0.29)cm、皮瓣面积与蒂宽比值7.35±2.75、手术时间(70.5±16.7)min、术中出血量(47.5±8.5)mL,对照组依次为(2.93±0.65)cm、2.75±0.82、(83.5±19.9)min、(60.5±15.0)mL,组间比较差异均有统计学意义(t=12.25、7.17、2.24、3.36,P值均<0.05)。观察组与对照组皮瓣存活率分别为95.0%(19/20)和90.0%(18/20),差异无统计学意义(χ^(2)=0.00,P=1.000)。观察组供瓣区直接缝合率为95.0%(19/20),高于对照组的60.0%(12/20),差异有统计学意义(χ^(2)=5.16,P=0.023)。术后6个月观察组血管循环VSS评分为(1.40±0.99)分,对照组为(1.65±0.81)分,差异无统计学意义(t=0.87,P=0.388);观察组皮瓣色泽、柔软度、厚度VSS评分及VSS总分分别为(0.90±0.64)、(2.00±1.03)、(1.30±0.92)、(5.60±3.27)分,对照组依次为(1.45±0.76)、(2.65±0.81)、(1.95±0.89)、(7.70±2.66)分,差异均有统计学意义(t=2.48、2.22、2.27、2.23,P值均<0.05)。观察组与对照组术后发生皮瓣对周围组织牵拉分别为7例和14例、蒂部猫耳形成分别为5例和16例,组间比较差异均有统计学意义(χ^(2)=4.91、12.13,P值均<0.05)。2组患者术后切口感染、出血、皮瓣下积液发生率比较,差异均无统计学意义(P值均>0.05)。结论采用窄蒂鼻唇沟皮下蒂皮瓣修复鼻部及鼻旁恶性肿瘤切除后的软组织缺损创面,对蒂部及供瓣区的处理优于传统的局部邻近皮瓣,且有效缩短手术时间、减少出血量、提高术后皮瓣美观度、减少并发症发生。

关键词：外科皮瓣窄蒂鼻唇沟皮下蒂皮瓣鼻部及鼻旁恶性肿瘤创面修复

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Function-oriented synthesis of Imidazo[1,2-a]pyrazine and Imidazo[1,2-b] pyridazine derivatives as potent PI3K/mTOR dual inhibitors

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EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY 2023年第1期247卷 115030页

作者： li, Chuchu Han, Yuqiao Wang, Zhengyang Yu, Yanan Wang, Chen Ren, Ziwei Guo, Yanzhi Zhu, Tong li, xuwen Dong, Suzhen Ma, Mingliang East China Normal Univ Shanghai Engn Res Ctr Mol Therapeut & New Drug Dev Sch Chem & Mol Engn Shanghai 200062 Peoples R China Shanghai Inst Mat Med Chinese Acad Sci State Key Lab Drug Res 555 Zu Chong Zhi RdZhangjiang Hitech Pk Shanghai 201203 Peoples R China Shanghai Univ Engn Sci Sch Math Phys & Stat Shanghai 201620 Peoples R China Bohai Rim Adv Res Inst Drug Discovery Shandong Lab Yantai Drug Discovery Yantai 264117 Peoples R China East China Normal Univ Key Lab Brain Funct Genom Minist Educ Shanghai 200062 Peoples R China

The PI3K-Akt-mTOR signaling pathway is a highly frequently activated signal transduction pathway in human malignancies, which has been a hot target for anti-tumoral drug discovery. Based on our previous research, a function-oriented synthesis (FOS) of imidazo[1,2-a]pyrazines and imidazo[1,2-b]pyridazines was conducted, and their anticancer activities in vitro and in vivo were evaluated. Among them, compound 42 exhibited excellent dual PI3K/mTOR inhibitory activity, with IC50 values on PI3K alpha and mTOR of 0.06 nM and 3.12 nM, respectively, much better than our previous reported compound 15a. Furthermore, compound 42 exhibited significant in vitro and in vivo anti-tumoral activities, great kinase selectivity, low hepatotoxicity, modest plasma clearance and acceptable oral bioavailability, which is a promising PI3K/mTOR targeted anti-cancer drug candidate.

关键词： PI3K mTOR dual inhibitors Cancer Antitumor activity Hepatotoxicity

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Recent advances in theoretical studies on transition-metal-catalyzed regioselective C-H functionalization of indoles

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JOURNAL OF MOLECULAR MODEliNG 2022年第9期28卷 267-267页

作者： Ma, Hongsheng Yu, Tongyan Chi, Longxiao Huang, Cong li, xuwen Zhang, Rui Deng, Chao Nanjing Agr Univ Coll Sci Jiangsu Key Lab Pesticide Sci Nanjing 210095 Peoples R China Nanjing Agr Univ Coll Sci Dept Chem Nanjing 210095 Peoples R China

Indole compounds are widely found in natural products and drug candidates. The transition-metal-catalyzed regioselective C-H bond functionalization of indoles as the most efficient method for the synthesis of various functionalized indoles has been extensively studied in the past two decades due to its advantages of step economy and atom economy. In general, the catalysts included the transition-metals (Pd, Rh, Ru, Cu, Co, Fe, Zn, and Ga) and these reactions were accomplished with a remarkably wide range of coupling reagents for construction of various C-C and C-X (X =N, O, S) bonds. However, the general and important rules of the regioselectivity are not clear to date. Therefore, a comprehensive analysis through previous reported theoretical studies on transition-metal-catalyzed regioselective C-H bond functionalization of indoles was crucial and significant. In this review, we found that when the C-H bond activation process was the rate-determining step, the regioselectivity ordinarily occurred at the C7 or C4 positions (on benzene ring), and otherwise, the regioselectivity often occurred at C2 position (on pyrrole ring). For indoline substrates, the C-H bond functionalization occurred at the benzene ring.

关键词： Indole C-H functionalization Mechanism Regioselectivity Transition-metals

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