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具有分数Brown运动的分数阶中立型随机微分方程解的存在唯一性
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作者 李国平 韩婷 《河南师范大学学报(自然科学版)》 北大核心 2025年第3期104-111,共8页
研究了一类在Hilbert空间中具有分数Brown运动的分数阶中立型随机微分方程,利用Picard逐步逼近法得到了其非Lipschitz条件和弱化的线性增长条件下粘性解的新的存在唯一性的充分条件.所提的研究方法使得先前一些研究结果得到了拓展.最后... 研究了一类在Hilbert空间中具有分数Brown运动的分数阶中立型随机微分方程,利用Picard逐步逼近法得到了其非Lipschitz条件和弱化的线性增长条件下粘性解的新的存在唯一性的充分条件.所提的研究方法使得先前一些研究结果得到了拓展.最后通过具有分数Brown运动的随机非线性波动方程验证了理论的有效性. 展开更多
关键词 分数阶随机微分方程 分数Brown运动 粘性解 存在唯一性
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由分数Brown运动驱动的EGARCH模型
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作者 王玮莹 韩月才 《吉林大学学报(理学版)》 北大核心 2025年第1期41-46,共6页
针对传统EGARCH模型难以捕捉长记忆性的问题,通过引入分数Brown运动提出一个fBm-EGARCH模型,给出模型的二阶矩、四阶矩及协方差函数性质,并理论证明其长期记忆性.数值模拟结果表明,该模型不仅能准确捕捉短期波动,还能反映长期记忆性,从... 针对传统EGARCH模型难以捕捉长记忆性的问题,通过引入分数Brown运动提出一个fBm-EGARCH模型,给出模型的二阶矩、四阶矩及协方差函数性质,并理论证明其长期记忆性.数值模拟结果表明,该模型不仅能准确捕捉短期波动,还能反映长期记忆性,从而验证了模型的有效性. 展开更多
关键词 EGARCH模型 分数Brown运动 长期记忆性 流动性
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从《马说》到《Super-Moiré说》
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作者 马亚琪 黄美珍 +1 位作者 孟子杨 王宁 《物理》 北大核心 2025年第6期412-418,共7页
在凝聚态物理学领域,量子莫尔材料研究正当其时。文章将从一篇物理学版《马说》讲起,引导读者欣赏该领域的新进展:如何通过量子干涉效应,得到更大晶格长度的super-Moiré(超莫尔)材料,实现前人开拓却所不及的整数磁通布洛赫态和整数... 在凝聚态物理学领域,量子莫尔材料研究正当其时。文章将从一篇物理学版《马说》讲起,引导读者欣赏该领域的新进展:如何通过量子干涉效应,得到更大晶格长度的super-Moiré(超莫尔)材料,实现前人开拓却所不及的整数磁通布洛赫态和整数Brown—Zak量子振荡。文章首先梳理了过去50年研究晶格势场中的电子在磁场中运动行为的来龙去脉,从侯世达蝴蝶能谱讲到石墨烯,再到转角石墨烯和现在的超莫尔材料,最后回到侯世达的名著《哥德尔、埃舍尔、巴赫》,完成从理论到计算再到实验的完整闭环。作者认为,超莫尔材料的实现为二维量子材料研究开辟了新路径,将会在量子通信和量子计算等领域具有重要应用前景。 展开更多
关键词 量子莫尔材料 磁布洛赫态 量子干涉效应 侯世达蝴蝶 Brown—Zak 振荡
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Hydroxy-α-sanshool-loaded adipose-targeted mesoporous silica nanoparticles induce white adipose browning and reduce obesity by activating TRPV1 被引量:1
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作者 Qing Zhang Chengxun He +5 位作者 Juan Guo Dandan Tang Die Qian Chuan Zheng Chunjie Wu Wei Peng 《Bio-Design and Manufacturing》 2025年第2期288-309,I0005-I0011,共29页
Obesity has become a global threat to health;however,the available drugs for treating obesity are limited.We investigated the anti-obesity effect of hydroxy-α-sanshool(HAS),an amide derived from the fruit of Zanthoxy... Obesity has become a global threat to health;however,the available drugs for treating obesity are limited.We investigated the anti-obesity effect of hydroxy-α-sanshool(HAS),an amide derived from the fruit of Zanthoxylum bungeanum,which promotes the management of obesity by triggering the browning of white adipose tissue(WAT)targeting the membrane receptor of transient receptor potential vanilloid 1(TRPV1).However,HAS easily undergoes configuration transformation and oxidative degradation.The short peptide CKGGRAKDC or adipose-targeting sequence(ATS)binds specifically to prohibitin on the surface of WAT cells and can be used as recognition assembly to enhance adipocyte targetability.Furthermore,mesoporous silica nanoparticles(MSNs)are widely used in drug delivery systems because of their large specific surface area and pore volume.Therefore,HAS-loaded adipose-targeted MSNs(MSNs-ATS)were developed to enhance the adipocyte targetability,safety,and efficacy of HAS,and tested on mature 3T3-L1 cells and obese mouse models.MSNs-ATS showed higher specificity for adipocyte targetability without obvious toxicity.HAS-loaded MSNs-ATS showed anti-obesity effects superior to those of HAS alone.In conclusion,we successfully developed adipocyte-targeted,HAS-loaded MSNs with good safety and anti-obesity effects. 展开更多
关键词 Hydroxy-α-sanshool Adipocyte targetability Mesoporous silica nanoparticles White adipose tissue browning OBESITY
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混合双分数Brown运动驱动的4/2-CIR模型及欧式期权定价
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作者 杨源 夏莉 《应用数学进展》 2025年第8期86-94,共9页
文章以资产价格的特征函数为研究工具,深入探讨了欧式期权的定价公式。在假定资产价格遵循混合双分数布朗运动驱动的4/2模型、随机利率遵循CIR模型以及随机波动率符合Heston模型的前提下,推导出了资产价格满足的广义特征函数的近似解析... 文章以资产价格的特征函数为研究工具,深入探讨了欧式期权的定价公式。在假定资产价格遵循混合双分数布朗运动驱动的4/2模型、随机利率遵循CIR模型以及随机波动率符合Heston模型的前提下,推导出了资产价格满足的广义特征函数的近似解析解表达式。进而,借助广义特征函数,巧妙运用傅里叶变换及其逆变换,成功构建出欧式看涨期权的定价公式,为欧式期权定价研究提供了新的分析思路。 展开更多
关键词 模板混合双分数Brown运动 4/2模型 广义特征函数 傅里叶变换
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腹腔镜远端胃癌根治术中不同吻合方式的应用对比 被引量:1
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作者 黄向上 焦光辉 +1 位作者 李永强 林功攀 《实用癌症杂志》 2025年第3期463-466,483,共5页
目的 探讨在腹腔镜远端胃癌根治术中应用不同方式吻合的临床效果。方法 采用前瞻性随机对照研究,纳入拟行腹腔镜远端胃癌根治术治疗的64例患者,依据随机数字表法分为A组(32例,U-RY吻合术)和B组(32例,改良BillrothⅡ+Brown吻合术)。比较... 目的 探讨在腹腔镜远端胃癌根治术中应用不同方式吻合的临床效果。方法 采用前瞻性随机对照研究,纳入拟行腹腔镜远端胃癌根治术治疗的64例患者,依据随机数字表法分为A组(32例,U-RY吻合术)和B组(32例,改良BillrothⅡ+Brown吻合术)。比较2组患者围术期指标、术前和术后肿瘤标志物[癌胚抗原(CEA)、糖类抗原19-9(CA19-9)]水平、胃肠道功能[胃肠道症状评定量表(GSRS)]、生活质量[卡氏功能状态评分(KPS)]以及术后并发症发生情况。结果 A组术中出血量少于B组,首次排气时间、手术时间、住院时间短于B组(P<0.05)。术后3个月和术后6个月时,2组血清CA19-9、CEA水平均低于术前(P<0.05),但组间差异无统计学意义(P>0.05)。术后3个月和术后6个月时,A组GSRS评分高于B组(P<0.05)。术后6个月时,A组KPS评分低于B组(P<0.05)。A组术后并发症总发生率高于B组(P<0.05)。结论 U-RY吻合术和改良BillrothⅡ+Brown吻合术应用于腹腔镜远端胃癌根治术中,均可降低肿瘤标志物水平,但相较于后者,前者术中出血量较少,住院时间、首次排气时间、手术时间较短,但术后并发症发生率较高,而后者在改善患者胃肠道功能和提高患者生活质量方面效果更好,临床可根据实际情况选择合理的吻合方式。 展开更多
关键词 腹腔镜远端胃癌根治术 U-RY吻合术 改良BillrothⅡ+Brown吻合术
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Two new species of Coniophora(Coniophoraceae,Boletales)from Hainan Province,China
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作者 LI Yue ZHU Qizhi +1 位作者 HE Shuanghui ZHU Anhong 《菌物学报》 北大核心 2025年第7期11-18,共8页
Coniophora is a widely distributed genus that includes species with resupinate basidiomata causing brown rot on fallen trees.In this study,two new species,Coniophora granulosa and Coniophora hainanensis,are described ... Coniophora is a widely distributed genus that includes species with resupinate basidiomata causing brown rot on fallen trees.In this study,two new species,Coniophora granulosa and Coniophora hainanensis,are described from Hainan Province based on molecular and morphological evidence.C.granulosa is characterized by having coriaceous basidiomata with granulose and light orange to grayish-orange hymenophore,relatively large and ellipsoid basidiospores measuring 12.5–14.2×8.2–9.5μm.C.hainanensis is characterized by having membranaceous basidiomata with smooth and grayish-orange to brownish orange hymenophore and fimbriate margin,and oblong-ellipsoid basidiospores measuring 9.8–12.2×5.2–6.5μm.Descriptions and illustrations are provided for the two new species. 展开更多
关键词 wood-decaying fungi corticioid fungi brown rots TAXONOMY PHYLOGENY new species
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Research Progress and Challenges of Tobacco Brown Spot
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作者 Dongkun WANG Ping LYU +12 位作者 Bin WANG Jijun NIU Guohua ZONG Yongqing XU Hairong XU Xiaojie BAI Weina ZHANG Yushan ZHANG Hanyu WU Songwei LIU Xianzhi ZHU Feng LI Lei TIAN 《Plant Diseases and Pests》 2025年第2期1-7,共7页
This paper provide a comprehensive overview of research findings regarding the pathogen responsible for tobacco brown spot,its occurrence regularity,and integrated control strategies.Additionally,this study provide a ... This paper provide a comprehensive overview of research findings regarding the pathogen responsible for tobacco brown spot,its occurrence regularity,and integrated control strategies.Additionally,this study provide a brief analysis of the challenges encountered in the study of tobacco brown spot,which include the study of pathogenesis and virulence,the breeding of disease-resistant varieties,the screening of low-toxicity and high-efficiency agents,the development of biological control methods with more stable efficacy,and the necessity for accurate prediction and forecasting techniques. 展开更多
关键词 TOBACCO BROWN SPOT INTEGRATED control CHALLENGE
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Why My Favourite Pet Is Special
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作者 张盼 陈传光 《中学生英语》 2025年第14期6-6,共1页
My favourite pet is a lovely dog.I bought him last year in the pet market.He has long ears,a long body and brown fur.He is very small.He weights①about one kilogram.He is very active.He wants to catch everything.Every... My favourite pet is a lovely dog.I bought him last year in the pet market.He has long ears,a long body and brown fur.He is very small.He weights①about one kilogram.He is very active.He wants to catch everything.Every day he runs here and there.But if you want him to do something,he will be a very good boy. 展开更多
关键词 brown fur active weight long ears small long body FAVOURITE DOG
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Harnessing Advanced Genomic Approaches to Unveil and Enhance Brown Planthopper Resistance in Rice
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作者 Lakshmi V.G.ISHWARYA S.VANISRI +5 位作者 P.S.BASAVARAJ M.SREEDHAR Lakshmi V.JHANSI M.MUNTAZIR C.GIREESH S.N.C.V.L.PUSHPAVALLI 《Rice science》 2025年第3期339-352,共14页
Brown planthopper(BPH)is a highly destructive pest that presents a significant challenge to rice production,particularly in the Asia-Pacific region.Numerous BPH-resistant rice varieties have been successfully bred and... Brown planthopper(BPH)is a highly destructive pest that presents a significant challenge to rice production,particularly in the Asia-Pacific region.Numerous BPH-resistant rice varieties have been successfully bred and released for commercial cultivation across diverse rice-growing ecosystems.However,resistance breakdown in several varieties carrying major resistance genes has been reported,highlighting the urgent need for the development of novel,genetically diverse,and broad-spectrum resistant varieties.To date,more than 45 resistance loci have been identified and mapped from both cultivated and wild rice species.Among these,a subset of genes(including Bph1,Bph3,Bph6,Bph7,Bph9,Bph10,Bph14,Bph15,Bph18,Bph21,Bph26/2,bph29,Bph32,Bph37,and Bph30/Bph40)have been positionally cloned.Most of these genes encode coiled-coil nucleotide-binding leucine-rich repeat proteins,which are central to plant immune responses,along with a few signaling molecules playing pivotal roles.In addition to these core resistance genes,various other genetic components,including miRNAs,protein kinases,and transcription factors,have been functionally characterized for their roles in mediating BPH resistance.The advent of post-genomic tools such as RNA sequencing and single-cell sequencing,along with cutting-edge genomic technologies like CRISPR/Cas gene editing,has significantly accelerated resistance breeding programs.In this context,we provide an overview of genetics,mapping,isolation,and functional characterization of BPH resistance,along with strategies for incorporating resistance using advanced genomics-assisted breeding tools.Furthermore,we present a snapshot of how the integration of genomics and novel breeding technologies holds great promise for dissecting the genetic architecture of pest resistance and accelerating crop improvement. 展开更多
关键词 brown planthopper CLONING CRISPR/Cas GENOMICS mapping
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Cordycepin ameliorates brown adipose tissue whitening induced by long-term continuous light exposure via the AMPK/PGC-1α/UCP1 signaling pathway
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作者 Ruonan Zhang Li Zhang +6 位作者 Yuqing Jiang Zhiwei Zhao Guanyu Zhang Yongqiang Zhang Shuai Wu Xi Li Danfeng Yang 《Frigid Zone Medicine》 2025年第3期129-140,I0003,I0004,共14页
Background:Long-term exposure to light has emerged as a novel risk factor for metabolic diseases.The whitening of brown adipose tissue(BAT)may play an important role in metabolic disorders caused by long-term continuo... Background:Long-term exposure to light has emerged as a novel risk factor for metabolic diseases.The whitening of brown adipose tissue(BAT)may play an important role in metabolic disorders caused by long-term continuous light exposure.This study aimed to investigate the morphological and functional alterations in BAT under continuous light conditions and to identify traditional Chinese medicine compounds capable of reversing these changes.Methods:A metabolic disorder model was established by subjecting mice to continuous light exposure for 5 weeks.During this period,body weight,food intake,and body fat percentage were monitored.Serum levels of triglyceride(TG),total cholesterol(TC),high density lipoprotein cholesterol(HDL-C),and low density lipoprotein cholesterol(LDL-C)were measured to assess lipid metabolism.Histological changes in BAT were examined using H&E staining.The expression of the thermogenic marker uncoupling protein 1(UCP1)in BAT was determined by RT-qPCR and Western blot to evaluate thermogenic function.RNA sequencing(RNA-seq)was employed to identify differentially expressed genes(DEGs)involved in BAT whitening induced by prolonged continuous light exposure.DEGs were analyzed using the connectivity map(CMap)database to identify potential preventive and therapeutic compounds.The therapeutic efficacy of the selected compounds was subsequently evaluated using the above indicators,and key pathways were validated through western blot analysis.Results:After 5 weeks of continuous light exposure,mice exhibited increased body fat percentage and serum levels of TG,impaired mitochondrial function,reduced thermogenic capacity,and whitening of BAT.Gene ontology(GO)and Kyoto encyclopedia of genes and genomes(KEGG)enrichment analyses indicated that BAT whitening was primarily associated with the adenosine 5'-monophosphate-activated protein kinase(AMPK)signaling pathway,fatty acid metabolism,and circadian rhythm.Ten hub genes identified using Cytoscape were mainly related to AMPK signaling and heat shock proteins.In vivo experiments showed that cordycepin significantly attenuated the increase in body fat percentage caused by prolonged light exposure.This effect was mediated by activation of the AMPK/PGC-1α/UCP1 signaling pathway,which restored the multilocular morphology and thermogenic function of BAT.Conclusion:Cordycepin mitigates continuous light-induced BAT whitening and metabolic disturbances by activating the AMPK signaling pathway. 展开更多
关键词 long-term continuous light brown adipose tissue WHITENING CORDYCEPIN AMPK
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Deficiency of circadian gene Per2 blocks luteolin-induced adipocyte browning in mice through weakening liver PPARα/RXRα/FGF21 pathway
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作者 Shanshan Shui Juan Chen +5 位作者 Yan Lin Jingjing Yuan Xin Wang Xian Zhang Jian Liu Lei Zheng 《Food Science and Human Wellness》 2025年第3期892-901,共10页
During the development of diet-induced obesity,the change of energy matebolism is closely related to the function of the circadian clock in mammals.Luteolin(LU),one of the most common natural flavonoids riched in many... During the development of diet-induced obesity,the change of energy matebolism is closely related to the function of the circadian clock in mammals.Luteolin(LU),one of the most common natural flavonoids riched in many edible plants,can ameliorate obesity by activating adipose tissue browning,but its effect on circadian clock in this process remains poorly understood.Here we found that dietary LU improved circadian misalignment of energy expenditure in high-fat diet(HFD)-fed wild-type(WT)mice.Moreover,dietary LU efficiently elevated uncoupling protein 1 levels in adipose tissue during the dark period,which was similar to the LU-increased hepatic PER2 expressions.Hepatic peroxisome proliferators-activated receptorsα(PPARα)/recombinant retinoid X receptorα(RXRα)/fibroblast growth factor 21(FGF21)pathway was rhythmically elevated by dietary LU in HFD-fed WT mice,whereas the promotion was inhibited in Per2^(-/-)mice.Meanwhile,Per2 deletion abolished the effects of dietary LU on adipose tissue browning in HFD-fed mice.Further,LU treatment directly activated PPARα/RXRα/FGF21 signaling in primary cultured hepatocytes from WT mice rather than Per2^(-/-)mice.Taken together,the deletion of the core clock component Per2 impedes LUinduced adipose tissue browning through weakening PPARα/RXRα/FGF21 pathway in mice,providing a new insight into the interplay of energy metabolism and circadian clock for the anti-obesity activity of LU. 展开更多
关键词 Obesity Circadian clock LUTEOLIN Per2 gene Adipose tissue browning
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Characteristic Analysis of Penta-Resistance Restorer Line for Hybrid Rice
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作者 LI Xinyan WENG Lüshui +7 位作者 XIAO Youlun LI Jinjiang DENG Lihua LIU Qing KANG Weiwei DUAN Yaping YANG Daji XIAO Guoying 《Rice science》 2025年第4期512-524,I0044-I0049,共19页
Rice often suffers from pests,diseases,and weeds throughout its life cycle.The management of pests,diseases,and weeds with agrochemicals increases production costs and results in pesticide residues.Developing new germ... Rice often suffers from pests,diseases,and weeds throughout its life cycle.The management of pests,diseases,and weeds with agrochemicals increases production costs and results in pesticide residues.Developing new germplasm and varieties with multiple resistances is the most economical,sustainable,and efficient way to solve these problems.In this study,marker-assisted backcrossing was used to pyramid multiple resistance genes,resulting in the development of a penta-resistance restorer line,B2A1920.This line was evaluated for its agronomic traits and resistance to diseases,pests,and herbicides.It was confirmed that B2A1920 contains the herbicide resistance gene Bar,the lepidopteran pest resistance gene Cry2Aa,the bacterial blight(BB)resistance gene Xa23,the blast resistance gene Pi2,and the brown planthopper(BPH)resistance genes Bph14 and Bph15.These genes confer resistance to glufosinate,lepidopteran pests,BB,blast,and BPH,respectively,while the line also exhibits elite agronomic traits.Its hybrids,Gui A×B2A1920,Quan 9311A×B2A1920,Yexiang A×B2A1920,Xianglong A×B2A1920,Tiantai A×B2A1920,and Shen 9A×B2A1920,likewise showed penta-resistance and superior agronomic performance.These results indicate the successful development of a cytoplasmic male sterile restorer line with high combining ability and penta-resistance. 展开更多
关键词 hybrid rice RESISTANCE non-selective herbicide rice blast bacterial blight lepidopteran pest brown planthopper
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Pomegranate peel polyphenols improves diet-induced obesity and promotes adipose browning development through gut microbiota in mice
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作者 Zhuoting Luo Xiaoyu Song +2 位作者 Mengting Li Jianke Li Chen Hou 《Food Science and Human Wellness》 2025年第2期605-616,共12页
Gut microbiota regulate the activation of adipose browning,which promote energy dissipation and combat diet-induced obesity.Pomegranate peel polyphenols(PPPs)have been shown to reduce obesity,regulate lipid metabolism... Gut microbiota regulate the activation of adipose browning,which promote energy dissipation and combat diet-induced obesity.Pomegranate peel polyphenols(PPPs)have been shown to reduce obesity,regulate lipid metabolism in adipose tissue,and modulate the composition of gut microbiota in animal fed high-fat diet(HFD).However,the role of gut microbiota in the improvement of obesity by PPPs has not been elucidated.In current study,we applied antibiotics to inhibit gut microbiota in mice fed HFD and treated with PPPs.The results showed that the inhibition of gut microbiota impair the effect of PPPs on reducing obesity and promoting adipose browning,and change the fecal metabolomic profiles in respond to PPPs.Moreover,the inhibition of gut microbiota supressed the promotive effects of PPPs on the levels of Akkermansia and microbiota-related metabolites,such as urolithin A,short-chain fatty acids(SCFAs),and bile acids(BAs),which were associated with activating adipose browning.Therefore,our results suggested that the presence of gut microbiota is essential for PPPs to ameliorate HFD-induced obesity.The related bacteria or metabolites generated by the interaction between PPPs and microbiota promote adipose browning and facilitate the beneficial effects of PPPs. 展开更多
关键词 Pomegranate peel polyphenols OBESITY Gut microbiota High-fat diet Adipose browning
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pH-dependent reaction kinetics between glyoxal and ammonium sulfate in simulated cloud droplets
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作者 Kun Liu Tao Wang +5 位作者 Guohua Zhang Wei Sun Ye Yang Mingjin Tang Xinming Wang Xinhui Bi 《Journal of Environmental Sciences》 2025年第12期686-693,共8页
Aqueous-phase reactions between carbonyls and reduced nitrogen compounds play a considerable role in the formation of secondary organic aerosols and brown carbon in the atmosphere.However,the reported reaction rate co... Aqueous-phase reactions between carbonyls and reduced nitrogen compounds play a considerable role in the formation of secondary organic aerosols and brown carbon in the atmosphere.However,the reported reaction rate constants for these reactions have largely been limited to bulk aqueous-phase simulations,which may not accurately represent the real state of atmospheric cloud droplets.We employed an integration of optical tweezers and Raman spectroscopy to manipulate and analyze simulated cloud droplets(size range8000-10,000 nm),comprising a mixture of glyoxal and ammonium sulfate.This approach enabled us to delve into the intricate realm of their reaction kinetics at individual droplet level mimicking cloud droplets.Raman spectroscopy provided high temporal resolution(20 s)measurements of the changes in the amount of nitrogen-containing organics(or NOCs as represented by the C-N bond)within the droplets.The results indicate that the reaction follows first-order kinetics throughout the monitoring over 80-400 min.The average reaction rate constant for the formation of NOCs within the single droplet was determined to be(6.77±0.98)×10^(-5)s^(-1),up to three orders of magnitude higher than those through the bulk aqueous-phase simulations,especially at lower p H levels.Additionally,the reaction rate constant in single droplet increases with increasing p H,consistent with the trend previously reported for the bulk aqueous-phase simulations.The results highlight the difference of the reaction rate constant between bulk aqueous-phase and droplets,which would improve our understanding on the formation and impacts of secondary organic aerosols and brown carbon in atmospheric aqueous phase. 展开更多
关键词 Optical tweezer-Raman spectroscopy Single droplet Ammonium sulfate Aqueous phase reaction Brown carbon
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Research progress on secondary formation,photosensitive reaction mechanism and human health effects of chromophoric brown carbon
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作者 Baihang Chen Jiangyao Chen +1 位作者 Guiying Li Taicheng An 《Journal of Environmental Sciences》 2025年第5期310-330,共21页
Brown carbon(BrC)has attracted widespread attention because of its strong absorption of solar radiation in the ultraviolet-visible wavelength range,which causes adverse impacts on human health.Originally,BrC was a phy... Brown carbon(BrC)has attracted widespread attention because of its strong absorption of solar radiation in the ultraviolet-visible wavelength range,which causes adverse impacts on human health.Originally,BrC was a physically defined class of substances.However,current research has gradually shifted towards the identification of its chemical groups,because its light-absorbing capability,chemical properties and health effects mainly depend on the chemical composition of its chromophores.Therefore,this review mainly focuses on the chemical understanding of BrC based on chromophores,and the secondary formation mechanism of chromophores,photosensitized reactions,and human health effects of BrC were detailly summarized.Firstly,BrC chromophores are divided into five categories:nitrogen-heterocycles,nitrogen-chain,aromatic species,oligomers and sulfur-containing organic compounds.Different chromophore precursor species exhibit variations,and their formation mechanisms are also distinct.Secondly,BrC can trigger the production of secondary organic aerosol(SOA)precursors or cause SOA growth because BrC is an important component of light-absorbing particles formed during incomplete combustion of biomass and fossil fuels,potentially exerting adverse effects on human health.Finally,developing sufficiently separated methods for BrC and refining algorithms and machine learning can lead to a more effective understanding of the chemical composition of chromophores,thus enabling better evaluation of the atmospheric effects and health impacts of BrC.In all,this review provides new insights into the categories of BrC chromophores and new advance in secondary formation mechanisms,photosensitized reactions,and human health effects on the basis of chemical structures. 展开更多
关键词 Brown carbon Constituent characteristics Secondary formation mechanism PHOTOSENSITIVE Human health effects
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Innovative IP Development and Industrial Integration of Yiwu Brown Sugar From the Perspective of Intangible Cultural Heritage Activation
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作者 CHEN Zimo HONG Yuting +1 位作者 SHEN Xinyuan FANG Xiaoqing 《Cultural and Religious Studies》 2025年第11期648-652,共5页
Against the backdrop of intangible cultural heritage(ICH)activation in China,the innovative transmission and industrial integration of ICH have become increasingly significant.As an officially recognized ICH item of Z... Against the backdrop of intangible cultural heritage(ICH)activation in China,the innovative transmission and industrial integration of ICH have become increasingly significant.As an officially recognized ICH item of Zhejiang Province,Yiwu brown sugar embodies unique artisanal techniques and carries the cultural memory of Yiwu.However,it currently faces challenges such as discontinuity in transmission,insufficient market recognition,and inadequate industrial integration.Focusing on the construction of a youth-oriented IP system for Yiwu brown sugar within the framework of ICH activation,this study employs field investigations and literature research to excavate the historical,cultural,and craft-related foundations of Yiwu brown sugar.It proposes strategies for developing a youthful IP identity through visual system innovation,digital content creation,and social-media-based dissemination,and explores integrated development pathways across culinary innovation,cultural and creative industries,and digital marketing.The aim is to provide theoretical support and practical guidance for the activation of Yiwu brown sugar as intangible cultural heritage. 展开更多
关键词 intangible cultural heritage activation Yiwu brown sugar IP innovation industrial integration
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Genome-Wide Association Study of Brown Rice Weight Identifies an RNA-Binding Protein Antagonistically Regulating Grain Weight and Panicle Number
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作者 ZHOU Lin JIANG Hong +11 位作者 HUANG Long LI Ziang YAO Zhonghao LI Linhan JI Kangwei LI Yijie TANG Haijuan CHENG Jinping BAO Yongmei HUANG Ji ZHANG Hongsheng CHEN Sunlu 《Rice science》 2025年第4期525-536,I0050-I0065,共28页
Rice grain yield is primarily determined by three key agronomic traits:panicle number,grain number per panicle,and grain weight(GW).However,the inherent tradeoffs among these yield components remain a persistent chall... Rice grain yield is primarily determined by three key agronomic traits:panicle number,grain number per panicle,and grain weight(GW).However,the inherent tradeoffs among these yield components remain a persistent challenge in rice breeding programs.Notably,compared with GW,brown rice weight(BRW)provides a more direct metric associated with actual grain yield potential.In this study,we conducted a two-year replicated genome-wide association study to elucidate the genetic architecture of BRW and identify new loci regulating GW.Among seven consistently detected loci across experimental replicates,four were not co-localized with previously reported genes associated with BRW or GW traits.BRW1.1,one of the four newly identified loci,was found to encode a novel RNA-binding protein.Functional characterization revealed that BRW1.1 acts as a negative regulator of BRW,potentially through modulating mRNA translation processes.Intriguingly,through integrated analysis of mutant phenotypes and haplotype variations,we demonstrated that BRW1.1 mediates the physiological tradeoff between GW and panicle number.This study not only delineates the genetic determinants of BRW but also identifies BRW1.1 as a promising molecular target for breaking the yield component tradeoff in precision rice breeding. 展开更多
关键词 genome-wide association study brown rice weight RNA-binding protein TRADEOFF grain weight panicle number grain number rice yield
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Characteristics of Submicron Aerosols (PM_(1)) in a Yangtze River Delta Megacity:Composition,Sources,and Light Absorption
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作者 Shiyue YANG Haifeng MENG +8 位作者 Ning ZHANG Shijie CUI Yuanjie SHAN Yu HUANG Yunlong XU Chongchong ZHANG Xinlei GE Mindong CHEN Junfeng WANG 《Advances in Atmospheric Sciences》 2026年第1期247-258,共12页
We conducted a field campaign to investigate the chemical composition,sources,and light absorption of submicron aerosols(PM_(1))from early 2022 in Nanjing,China.The average concentration of PM_(1) was 31μg m^(−3),org... We conducted a field campaign to investigate the chemical composition,sources,and light absorption of submicron aerosols(PM_(1))from early 2022 in Nanjing,China.The average concentration of PM_(1) was 31μg m^(−3),organics(33%)constituted the largest fraction,followed by nitrate(30%),sulfate(18%),ammonium(15%),chloride(3%),and rBC(2%).Four organic aerosol(OA)subcomponents were identified,including two primary OA(POA)and two secondary OA(SOA).The less-oxidized SOA(LO-OOA)contributes the most to the total OA mass(59%).LO-OOA is tightly correlated with the tracer ion C_(2)H_(4)O_(2)^(+)from levoglucosan,and another aged biomass-burning derived species,K_(3)SO_(4)^(+),suggesting it was likely influenced by aged biomass-burning OA.Our study also revealed that fireworks during the Spring Festival have a detrimental impact on air quality,contributing to secondary formation and accumulation under static winter meteorological conditions,prolonging the pollution duration.Also,LO-OOA was found to have the strongest light-absorbing ability.Our results highlight that the light absorption of LO-OOA can mainly be attributed to the C_(x)H_(y)N^(+) family,increased with the double-bond equivalent value.The more-oxidized SOA(MO-OOA)exhibited a negligible light absorption and was strongly correlated with daytime photochemical processes,implying a light-bleaching effect.This study enhances our understanding of the regional contribution of biomass combustion and fireworks to PM_(1) pollution in Nanjing,a typical megacity in the Yangtze River Delta region,during winter,aiding in the development of strategies for long-term air quality improvement in the region. 展开更多
关键词 PM_(1) source apportionment Yangtze River Delta Region brown carbon
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The rediscovery of Mozart's hidden gem
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作者 孙启禄 《疯狂英语(新悦读)》 2025年第4期25-28,76,共5页
1 In 2024,audiences were treated to something very special:new music by Wolfgang Amadeus Mozart.That's right-new Mozart music!2 Leipzig Municipal Libraries announced their exciting find.Researchers came across thi... 1 In 2024,audiences were treated to something very special:new music by Wolfgang Amadeus Mozart.That's right-new Mozart music!2 Leipzig Municipal Libraries announced their exciting find.Researchers came across this lost work while updating the Köchel catalogue,a list of Mozart's compositions.The piece is a seven⁃movement string trio,written in the mid to late 1760s,when Mozart was very young.The handwritten manuscript,titled Serenate ex C,uses dark brown ink on off⁃white paper.Now,it's been renamed Ganz kleine Nachtmusik and lasts about 12 minutes. 展开更多
关键词 new music dark brown ink string trio ganz kleine n REDISCOVERY hidden gem k chel cataloguea K chel catalogue
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