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Towards an l^p Potential Theory for Sub-Markovian Semigroups:Kernels and Capacities

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1227-1250页

作者： Niels JACOB Renél.SCHIllING Department of Mathematics University of Wales SwanseaSingleton ParkSwansea SA 2 8 PP.United Kinadom FB 12-Mathematik Philipps-Universitat MarburgD-35032 MarburgGermany

We study in fairly general measure spaces （X,μ） the （non-linear） potential theory of l^p sub-Markovian semigroups which are given by kernels having a density with respect to the underlying measure. In terms of mapping properties of the operators we provide sufficient conditions for the existence （and regularity） of such densities. We give various （dual） representations for several associated capacities and, in the corresponding abstract Bessel potential spaces, we study the role of the truncation property. Examples are discussed in the case of R^n where abstract Bessel potential spaces can be identified with concrete function spaces.

关键词： nonlinear potential theory (r,p)-capacity Bessel potential space gamma.transform sub-Markovian semigroup

Kri1l: a novel gene that links defective ribosome biogenesis to impaired hematopoiesis through excessive autophagy

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Science Bulletin 2015年第17期60卷 1547-1548页

作者： Yong Zhang David l.Wiest Blood Cell Development and Function Program Fox Chase Cancer Center Philadelphia

The ribosome is an ancient and conserved molecular machine responsible for translating mRNA into protein in all known organisms. The eukaryotic ribosome is com- posed of - 80 ribosomal proteins （RPs） and four ribosomal RNAs （rRNAs）. These RNA and protein components are assembled within the nucleolus into the small 40S and large 60S subunits of the ribosome, through a process termed ribosome biogenesis. Ribosome biogenesis is a highly orchestrated and carefully controlled process that requires - 150 associated proteins and 70 small nucleolar RNAs （snoRNAs）, which assist in prerRNA transcription and maturation, ribosome component assembly, and trafficking to the cytosol. Defects in ribosome biogenesis resulting from mutations in biogenesis cofactors, or in ribosomal structural components themselves, cause a collection of human diseases termed ＂ribosomopathies＂.

关键词： Ribosome biogenesis Hematopoietic stem cell Autophagy Ribosomopathy Zebrafish

呋虫胺和唑虫酰胺在茶叶加工过程中的残留特征及膳食风险评估

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食品科学 2025年第1期46卷 192-199页

作者：李春勇吕莹金静王霞秦曙山西农业大学山西功能农产品检验检测中心山西太原030031

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后... 详细信息

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后,经超高效液相色谱-串联质谱法检测,外标法定量。结果表明:在0.005~0.500μg/ml范围内,呋虫胺及其代谢物、唑虫酰胺质量浓度与其响应峰面积呈良好线性关系(R^(2)>0.99),在0.05、1.00、20.00、50.00 mg/kg(茶鲜叶、茶干叶),0.05、0.10、5.00 mg/kg(茶汤)添加水平下,呋虫胺及其代谢物1-甲基-3-[(3-四氢呋喃)甲基]脲、1-甲基-3-[(3-四氢呋喃)甲基]二氢胍盐的平均加标回收率为74%~103%,相对标准偏差为1%~9%;唑虫酰胺的平均加标回收率为75%~95%,相对标准偏差为1%~6%,方法定量限均为0.05 mg/kg;20%呋虫胺·唑虫酰胺微乳剂按推荐剂量施药后,呋虫胺(含代谢物)在茶鲜叶中的规范残留试验中值(supervised trials median residue,STMR)经烘干因子校正后与茶干叶中STMR相应的国家估算每日摄入量(national estimated daily intake,NEDI)均为4.08 mg,占每日允许摄入量(allowable daily intake,ADI)的32.4%;唑虫酰胺在茶鲜叶中的STMR经烘干因子校正后的NEDI为0.17581 mg,占ADI的46.5%,茶干叶中STMR对应的NEDI为0.18925 mg,占ADI的50.1%,呋虫胺和唑虫酰胺在不同评估模型下获得的长期膳食暴露风险均低于100%;呋虫胺(含代谢物)经加工因子校正后的国际短期膳食摄入量(international estimation of short-term dietary intake,IESTI)与校正前处于同一风险水平,低于急性参考剂量(acute reference dose,ARfD)(1 mg/kg);唑虫酰胺的IESTI为3.46×10^(-4) mg/kg(采收间隔7 d),低于ARf D(0.01 mg/kg),本研究方法在茶汤中未检测到唑虫酰胺残留,故未得到浸泡因子及相应的IESTI。综上,按推荐剂量在茶树上使用20%呋虫胺·唑虫酰胺微乳剂是安全的,最终残留量对应的长期及急性膳食摄入风险均在可接受范围,利用加工因子校正评估模型更切合实际风险水平。

关键词：呋虫胺唑虫酰胺茶叶加工因子残留特征风险评估

High mechanical strengths and ductility of stainless steel 304l fabricated using selective laser melting

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Journal of Materials Science & Technology 2019年第2期35卷 388-394页

作者： Q.B.Nguyen Z.Zhu F.l.Ng B.W.Chua S.M.l.Nai J.Wei Singapore Institute of Manufacturing Technology Institute of Research and Development Duy Tan University

Achieving not only high mechanical strengths but also high ductility is recently established using an additive manufacturing technique called selective laser melting. In the present study, stainless steel 304 l fully dense samples were successfully printed using the 3 D systems – ProX 300 printing machine. The ductility and tensile yield strength were almost two and three times higher compared to those of ASTM cast's alloy. Honey comb like nano-cellular structure with different orientation was observed in the fine grains(~4μm) due to fast cooling rate. In addition, the formation of martensite phase in random grains is also a contributor to the strengths. Furthermore, negative residual stresses in the build and horizontal directions were detected and assisted further increase in the tensile strength. Fractography revealed the ductile feature of plastic deformation and the crack openings at unmelted particles or pores.

关键词： Additive manufacturing Stainless steel Powder Selective laser melting

FHl2 deficiency aggravates Candida albicans infection through decreased myelopoiesis

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Science China life Sciences 2025年

作者： Rongmei Gao Kanchao Chen Yimin Wang Rongxia Guo Xiaoyu Zhang Peng Wu Weili Wang Qingxiang Huang Xuemei Xie Shangda Yang Yanling lü Qian Ren Fei liu Song Chen Fengxia Ma Tao Cheng Hui Cheng State Key laboratory of Experimental Hematology National Clinical Research Center for Blood Diseases Haihe Laboratory of Cell Ecosystem Institute of Hematology & Blood Diseases Hospital Chinese Academy of Medical Sciences & Peking Union Medical College CAMS Center for Stem Cell Medicine PUMC Department of Stem Cell and Regenerative Medicine

Hematopoiesis is a finely tuned process that generates all blood cell types through self-renewal and differentiation, which is crucial for maintaining homeostasis. Acute infections can prompt a hematopoietic response known as emergency myelopoiesis. In this study, using a Candida albicans (C. albicans) infection model, we demonstrated for the first time that disruption of Fhl2 led to increased fungal burden,heightened inflammatory response and reduced survival rates. Impaired myeloid hematopoiesis and immune cell production were evident, as proved by the decreased numbers of hematopoietic stem and progenitor cells (HSPCs) and granulocytes in the bone marrow of Fhl2-deficient mice. In conclusion, FHl2 regulated emergency myelopoiesis in response to C. albicans, affecting the host’s defense against pathogens.

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Effect of Zn binding to phytate and humic substances on its uptake by wheat(Triticum durum l.)as affected by carbonates and Fe oxides

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Pedosphere 2022年第6期32卷 823-832页

作者： Ana M.GARCÍA-lÓPEZ Ramiro RECENA Antonio DElGADO Department of Agronomy ETSIAUniversity of SevilleSeville 41013(Spain)

Although complexation with soil organic matter may improve zinc(Zn)bioavailability to plants,the effect of Zn sorbent surface on the use of complexed Zn by plants remains *** objective of this research was to elucidate how Zn complexation with humic substances(HS)and phytate affects the uptake of Zn by wheat plants depending on the main sorbent surface in growth media,i.e.,carbonates and Fe *** this end,two pot experiments were performed,one using Fe oxide-coated siliceous as the siliceous growth medium sand and the other using a mixture of calcareous sand and siliceous sand as the calcareous growth *** experiment involved three Zn sources,Zn-HS complex,Zn phytate,and ZnSO_(4).All sources were applied with surface irrigation at two Zn rates(0.25 and 2 mg kg^(-1) growth medium).The Zn-HS complex significantly increased Zn uptake by plants in both media,relative to the other two Zn sources,but no significant difference was observed between Zn phytate and ZnSO_(4).In the calcareous medium,Zn-HS complex and Zn phytate resulted in significantly higher dry biomass yields of wheat than ZnSO_(4).In the siliceous medium,spike and shoot dry biomass yields with Zn-HS complex at the low rate and Zn phytate at both rates were not significantly different from those with ZnSO_(4) at the high *** harvest,approximately 50%of the Zn applied as Zn-HS complex remained extractable by diethylenetriaminepentaacetic acid(DTPA),while this proportion was less than 20%for the other Zn ***,Zn-HS complex and Zn phytate are sources of available Zn for plants,and they are more effective than ZnSO_(4) in increasing plant growth,particularly when carbonates are the main Zn sorbent surface.

关键词： calcareous growth medium micronutrient organic matter organic phosphorus Zn availability Zn deficiency Zn sorbent surface Zn source

Experimental study on reduction of U (Ⅵ) by an anaerobic bacterium, Shewanella putrefaciens: Application to sandstone-hosted interlayer oxidation-zone type uranium deposits, China

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Science China Earth Sciences 2005年第3期48卷 346-352页

作者： l.l.Barton Department of Biology University of New Mexico Albuquerque NM 87131-1116USA

An experimental study on reduction of U (VI) by anaerobic bacteria, Shewanella putrefaciens, is first reported here in China. The experimental conditions were: 35℃ and pH = 7.0—7.4, corresponding to a physicochemical environments in which the sandstone-hosted in- terlayer oxidation-zone type uranium deposit formed in Northwest China’s Xinjiang. Bacteria adopted in the present experiment, Shewanella putrefaciens, occur extensively in natural envi- ronment. Our study shows that nano-crystal precipitates of uraninite quickly occurred on the surface of the cells within one week. It was found that the pitchblende was characterized by a random arrangement of uraninite nanocrystals (2—4 nm) in it, significantly different from natural pitchblende in which uraninite nanocrystals are arranged in order. Finally, a possible mechanism of uranium biomineralization by microorganisms in the deposits is discussed. Our investigation may supply a technical train of thoughts for bioremediation of nuclear-contaminated water envi- ronments and for underground dissolving extraction of the sandstone-hosted uranium ores.

关键词： anaerobic bacteria, reduction, pitchblende, sandstone-hosted uranium deposit, experimental study.

NOD2 and ATG16l1 polymorphisms affect monocyte responses in Crohn's disease

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World Journal of Gastroenterology 2011年第23期17卷 2829-2837页

作者： Dylan M Glubb Richard B Gearry Murray l Barclay Rebecca l Roberts John Pearson Jacqui I Keenan Judy McKenzie Robert W Bentley Department of Medicine University of ChicagoIL 60637-1470United States Department of Medicine University of OtagoChristchurch8140New Zealand Department of Gastroenterology Christchurch HospitalChristchurch8140New Zealand Department of Biochemistry University of OtagoDunedin9054New Zealand Department of Pathology University of OtagoChristchurch8140New Zealand Department of Surgery University of OtagoChristchurch8140New Zealand Department of Haematology University of OtagoChristchurch8140New Zealand Department of Paediatrics University of OtagoChristchurch8140New Zealand

AIM： TO assess whether polymorphisms in NOD2 and ATG16l1 affect cytokine responses and mycobacterium avium subspecies paratuberculosis （MAP） survival in monocytes from Crohn＇s disease （CD） patients METHODS： Monocytes were isolated from peripheral blood of CD patients of known genotype for common single nucleotide polymorphisms of NOD2 and ATG16l1, Monocytes were challenged with MAP and bacterial per- sistence assessed at subsequent time-points. Cytokine responses were assayed using a Milliplex multi-analyte profiling assay for 13 cytokines. RESUlTS： Monooltes heterozygous for a NOD2 polymorphism （R702W, P268S, or 1007fs） were more permissive for growth of MAP （P = 0.045） than those without. There was no effect of NOD2 genotype on subsequent cytokine expression. The T300A polymorphism of ATG16l1 did not affect growth of MAP in our model （P = 0.175）, but did increase expression of cytokines interleukin （Il）-10 （P = 0.047） and Il-6 （P = 0.019）. CONClUSION： CD-associated polymorphisms affected the eliminaUon of MAP from ex v/vo monooltes （NOD2）, or expression of certain oltokines （ATG16lI）, implying independent but contributory roles in the pathogenesis of CD.

关键词： Inflammatory bowel disease Mycobacteriumavium subspecies paratuberculosis Cytokine CARD15 Autophagy

Three-dimensional dynamics of supported pipes conveying fluid

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Acta Mechanica Sinica 2017年第6期33卷 1065-1074页

作者： l.Wang T.l.Jiang H.l.Dai Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China Hubei Key laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074 China

This paper deals with the three-dimensional dynamics and postbuckling behavior of flexible supported pipes conveying fluid, considering flow velocities lower and higher than the critical value at which the buckling instability occurs. In the case of low flow velocity, the pipe is stable with a straight equilibrium position and the dynamics of the system can be examined using linear theory. When the flow velocity is beyond the critical value, any motions of the pipe could be around the postbuckling configuration(non-zero equilibrium position) rather than the straight equilibrium position, so nonlinear theory is required. The nonlinear equations of perturbed motions around the postbuckling configuration are derived and solved with the aid of Galerkin discretization. It is found, for a given flow velocity,that the first-mode frequency for in-plane motions is quite different from that for out-of-plane motions. However, the second-or third-mode frequencies for in-plane motions are approximately equal to their counterparts for out-of-plane motions, keeping almost constant values with increasing flow velocity. Moreover, the orientation angle of the postbuckling configuration plane for a buckled pipe can be significantly affected by initial conditions, displaying new features which have not been observed in the same pipe system factitiously supposed to deform in a single plane.

关键词： Pipe conveying fluid Three-dimensional dynamics Instability Natural frequency Postbuckling configuration