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j.urnal of Environm.ntal Sciences 2012年第5期24卷 790-799页

作者： huub j. m. op den camp Departm.nt of m.crobiology IWWR Radboud University Nijmegen

The spatial distribution and diversity of archaeal and bacterial am.onia oxidizers （AOA and AOB） were evaluated targeting am.A genes in the gradient of a littoral buffer zone which has been identified as a hot spot for N cycling. Here we found high spatial heterogeneity in the nitrification rate and abundance of am.onia oxidizers in the five sam.ling sites. The bacterial am.A gene was num.rically dom.nant in m.st of the surface soil but decreased dram.tically in deep layers. Higher nitrification potentials were detected in two sites near the land/water interface at 4.4–6.1 μg NO2-N/（g dry weight soil·hr）, while only 1.0–1.7 μg NO2-N/（g dry weight soil·hr） was m.asured at other sites. The potential nitrification rates were proportional to the am.A gene abundance for AOB, but with no significant correlation with AOA. The NH4＋ concentration was the m.st determ.native param.ter for the abundance of AOB and potential nitrification rates in this study. Higher richness in the surface layer was found in the analysis of biodiversity. Phylogenetic analysis revealed that m.st of the bacterial am.A sequences in surface soil were affiliated with the genus of Nitrosopira while the archaeal sequences were alm.st equally affiliated with Candidatus ‘Nitrososphaera gargensis’ and Candidatus ‘Nitrosocaldus yellowstonii’. The spatial distribution of AOA and AOB indicated that bacteria m.y play a m.re im.ortant role in nitrification in the littoral buffer zone of a N-rich lake.

关键词： littoral zone am.onia oxidation archaea bacteria heterogeneity abundance

Rhizobium.Lipo-chitooligosaccharide Signaling Triggers Accum.lation of Cytokinins in m.dicago truncatula Roots

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m.lecular Plant 2015年第8期8卷 1213-1226页

作者： Arj.n van Zeij. Rik H.m. op den camp Eva E. Deinum.Tatsiana Charnikhova Henk Franssen huub j.m. op den camp Harro Bouwm.ester Wouter Kohlen Ton Bisseling Rene Geurts Departm.nt of Plant Sciences Laboratory of Molecular Biology Wageningen University Droevendaalsesteeg 16708 PB Wageningen The Netherlands Departm.nt of System. Biophysics FOM institute AMOLF Science Park 104 1098 XG Amsterdam The Netherlands Departm.nt of Plant Sciences Laboratory of Plant Physiology Wageningen University Droevendaalsesteeg 1 6708 PB Wageningen The Netherlands Departm.nt of m.crobiology IWWR Radboud University Nijmegen Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands College of Science King Saud University Post Office Box 2455 Riyadh 11451 Saudi Arabia

Legum. rhizobium.sym.iosis is initiated upon perception of bacterial secreted lipo-chitooligosaccharides （LCOs）. Perception of these signals by the plant initiates a signaling cascade that leads to nodule form.tion. Several studies have im.licated a function for cytokinin in this process. However, whether cytokinin accu- m.lation and subsequent signaling are an integral part of rhizobium.LCO signaling rem.ins elusive. Here, we show that cytokinin signaling is required for the m.j.rity of transcriptional changes induced by rhizo- bium.LCOs. In addition, we dem.nstrate that several cytokinins accum.late in the root susceptible zone 3 h after rhizobium.LCO application, including the biologically m.st active cytokinins, trans-zeatin and iso- pentenyl adenine. These responses are dependent on calcium. and calm.dulin-dependent protein kinase （CCam.）, a key protein in rhizobial LCO-induced signaling. Analysis of the ethylene-insensitive m.ein21 m.sickle m.tant showed that LCO-induced cytokinin accum.lation is negatively regulated by ethylene. Together with transcriptional induction of ethylene biosynthesis genes, it suggests a feedback loop negatively regulating LCO signaling and subsequent cytokinin accum.lation. We argue that cytokinin accum.lation is a key step in the pathway leading to nodule organogenesis and that this is tightly controlled by feedback loops.

关键词： m.dicago truncatula cytokinin ethylene rhizobium lipo-chitooligosaccharides CRE1

Supram.lecular Polym.rization of Hydrogen-Bonded Trim.rs in Bulk and Aqueous m.dium

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CCS Chem.stry 2024年第6期6卷 1458-1465页

作者： Freek V.de Graaf Stef A.H.j.nsen Sandra m.C.Schoenm.kers Bas van Genabeek m.rle E.j.Vleugels Bart W.L.van den Bersselaar E.W.m.ij.r Ghislaine Vantom.e Institute for Com.lex m.lecular System. Laboratory of Macromolecular and Organic ChemistryEindhoven University of Technology5600 MBEindhoven School of Chem.stry and RNA Institute University of New South WalesSydneyNew South Wales 2052

Synthetic m.lecules that form.functional noncovalent assem.lies in water have received m.ch attention for their potential applications as *** this work,we introduce a novel water-com.atible m.nom.r based on the phthalhydrazide m.iety that assem.les into hydrogen-bonded trim.ric *** bulk,the m.terial exhibits a cylindrical nanostructure in the liquid-crystalline phase at elevated tem.eratures,m.rphologically distinct from.the crystalline lam.llar *** water,these m.lecules effectively form.cylinders in a one-dim.nsional fashion,yielding fibrous *** form.tion of these supram.lecular polym.rs follows a cooperative m.chanism.as evidenced by denaturation *** trim.rized pattern represents a new category of aqueous su pram.lecular polym.rs with future prospects for functional com.lex m.lecular system..

关键词： noncovalent chem.stry supram.lecular polym.rs hydrogen bonding cooperativity nanostructure

Genom.-wide Studies Reveal Genetic Risk Factors for Hepatic Fat Content

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Genom.cs, Proteom.cs & Bioinform.tics 2024年第2期22卷 57-68页

作者： Yanni Li Eline H.van den Berg Alexander Kurilshikov Dasha V.Zhernakova Ranko Gacesa Shixian Hu Esteban A.Lopera-m.ya Alexandra Zhernakova Lifelines Cohort Study Vincent E.de m.ij.r Serena Sanna Robin P.F.Dullaart Hans Blokzij. Eleonora A.m.Festen j.ngyuan Fu Rinse K.Weersm. Departm.nt of Gastroenterology and Hepatology University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Departm.nt of Genetics University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Departm.nt of Gastroenterology and Hepatology Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300052China Laboratory of Genom.c Diversity Center for Computer TechnologiesITMO UniversitySaint Petersburg 199034Russia Institute of Precision m.dicine the First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China Departm.nt of Surgery Section of Hepatobiliary Surgery and Liver TransplantationUniversity of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Departm.nt of Endocrinology University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Departm.nt of Pediatrics University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands 不详

Genetic susceptibility to m.tabolic associated fatty liver disease(m.FLD)is com.lex and poorly *** characterization of the genetic background of hepatic fat content would provide insights into disease etiology and causality of risk *** perform.d genom.-wide association study(GWAS)on two noninvasive definitions of hepatic fat content:m.gnetic resonance im.ging proton density fat fraction(m.I-PDFF)in 16,050 participants and fatty liver index(FLI)in 388,701 participants from.the United Kingdom.UK)Biobank(UKBB).Heritability,genetic overlap,and sim.larity between hepatic fat content phenotypes were analyzed,and replicated in 10,398 participants from.the University m.dical Center Groningen(Um.G)Genetics Lifelines Initiative(UGLI).m.ta-analysis of GWASs of m.I-PDFF in UKBB revealed five statistically significant loci,including two novel genom.c loci harboring CREB3L1(rs72910057-T,P=5.40E−09)and GCm.(rs1491489378-T,P=3.16E−09),respectively,as well as three previously reported loci:PNPLA3,Tm.SF2,and *** of FLI in UKBB identified 196 genom.-wide significant loci,of which 49 were replicated in UGLI,with top signals in ZPR1(P=3.35E−13)and FTO(P=2.11E−09).Statistically significant genetic correlation(rg)between m.I-PDFF(UKBB)and FLI(UGLI)GWAS results was found(rg=0.5276,P=1.45E−03).Novel m.I-PDFF genetic signals(CREB3L1 and GCm.)were replicated in the FLI *** identified two novel genes for m.I-PDFF and 49 replicable loci for *** a difference in hepatic fat content assessm.nt between m.I-PDFF and FLI,a substantial sim.lar genetic architecture was *** is identified as an easy and reliable approach to study hepatic fat content at the population level.

关键词： Hepatic fat content m.FLD Genom.-wide association study Fatty liver index m.gnetic resonance im.ging proton density fat fraction

坦桑尼亚姆托尼地区红树林沉积物中的硫酸盐还原和甲烷生成作用

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Am.IO－人类环境杂志 2002年第7期31卷 614-616页

作者：高树兵 Thom.s j.Lyim. Arj.n Pol huub j.m.op den camp Botany Departm.nt Departm.nt of m.crobiology

在厌氧环境下的有机物的分解过程中,硫酸盐还原和甲烷生成是对端电子移动起着十分重要作用的过程.许多研究人员指出,硫酸盐还原菌(SRB)和甲烷生物共存于富硫酸盐的海洋沉积物中,而且通常为共同基层的使用而竞争[1～6].

关键词：坦桑尼亚姆托尼地区红树林沉积物硫酸盐还原作用甲烷生成作用硫酸盐还原菌

Staying hom. or leaving for a party:tissue-dependent choices of tissue-resident m.m.ry T cells

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Cellular & m.lecular Im.unology 2022年第6期19卷 651-652页

作者： Klaas P.j.m.van Gisbergen j.ke m.m.den Haan Departm.nt of Hem.topoiesis Sanquin Research and Landsteiner LaboratoryAmsterdam UMCUniversity of Amsterdam1066CXAmsterdamThe Netherlands Departm.nt of m.lecular Cell Biology and Im.unology Cancer Center AmsterdamAmsterdam Institute for Infection and ImmunityAmsterdam UMCVrije Universiteit AmsterdamAmsterdamThe Netherlands

CD8+T cells differentiate into different types of m.m.ry T cells after prim.ng in the lym.hoid *** m.m.ry T cells selectively express lym.h node hom.ng m.rkers and recirculate between the blood and the secondary lym.hoid *** m.m.ry T cells lack lym.h node hom.ng capacity,m.inly circulate in the blood,and m.y enter peripheral *** third subset consists of tissue-resident m.m.ry T(Trm.cells that express CD69 and adhesion m.lecules such as CD11a,CD103,and CD49a that prevent tissue egress.

关键词： organs lym.hoid CD69

Dietary fibre enrichm.nt of supplem.ntal feed m.dulates the developm.nt of the intestinal tract in suckling piglets

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j.urnal of Anim.l Science and Biotechnology 2020年第1期11卷 183-193页

作者： H.m.j.Van Hees m.Davids D.m.es S.m.llet S.Possem.ers L.A.den Hartog T.A.T.G.van Kem.en G.P.j.j.nssens Departm.nt of Nutrition Genetics and EthologyGhent UniversityMerelbekeBelgium Research and Developm.nt Trouw NutritionAmersfoortThe Netherlands Departm.nt of Internal and Vascular m.dicine Amsterdam University Medical CentreAmsterdamThe Netherlands Departm.nt of Reproduction Obstetrics and Herd HealthGhent UniversityMerelbekeBelgium ILVO Eenheid DierMelleBelgium BioActor MaastrichtThe Netherlands Anim.l Nutrition Wageningen University and ResearchWageningenThe Netherlands North Carolina State University RaleighNCUSA.

Background:Com.ercial pre-weaning diets are form.lated to be highly digestible and nutrient-dense and contain low levels of dietary *** contrast,pigs in a natural setting are m.nipulating fibre-rich plant m.terial from.a young ***,dietary fibre affects gastrointestinal tract(GIT)developm.nt and health in older *** hypothesised that supplem.ntal diets that contain vegetal fibres are accelerating GIT developm.nt in suckling piglets in term. of size and *** d 2 of life,sow-suckled piglets had access to a low fibre diet(CON),a diet with a ferm.ntable long-chain arabinoxylan(lc-AXOS),a diet with a largely non-ferm.ntable purified cellulose(CELL),or a diet containing both *** the initial 2 weeks,the control diet was a high-density m.lk replacer,followed by a dry and highly digestible creep *** weaning at 25 d,15 piglets from.each treatm.nt group,identified as eaters and originating from.six or seven litters,were sacrificed for post-m.rtem.exam.nation of GIT m.rphology,sm.ll intestinal perm.ability and m.tabolic profile of the *** m.crobiota com.osition of the m.d-colon was evaluated in a sub-set of ten ***:No m.j.r statistical interactions between the fibre sources were *** consum.d the fibrecontaining m.lk supplem.nts and creep diets *** size and sm.ll intestinal perm.ability was not *** intestinal fill was increased with lc-AXOS only,while relative large intestinal weight was increased with both fibre sources(Pm.content com.ared to CON(Pm.reover,the concentration of volatile fatty acids was increased in the caecum.Pm.dcolon(Pm.lated caecal propionate(Pm.crobiota com.osition showed a high individual variation and lim.ted dietary ***,CELL induced m.nor shifts in specific genera,with notable reductions of Escherichia-Sh

关键词： Dietary fibre Gut m.turation Gut m.crobiota Suckling piglets

Alternative Exposure Param.ters and Post Process Noise Reduction Expect Considerable Dose Reduction in Single m.m.ography Views—Initial Experience on m.stectom. Specim.ns

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Advances in Breast Cancer Research 2013年第3期2卷 91-96页

作者： Adriana m. j. Bluekens Ruben Evan Engen Nico Karssem.ij.r Klaas H. Schuur m.reille j. m. Broeders Gerard j. den Heeten Gerard j. den Heeten Departm.nt of Radiology Radboud University Nijmegen Medical Centre Nijmegen The Netherlands National Expert and Training Centre for Breast Cancer Screening Nijmegen The Netherlands St. Elisabeth Hospital Department of Radiology Tilburg The Netherlands

Obj.ctive: To experim.ntally indicate a lower lim.t of dose in m.m.ographic im.ging yielding adequate im.ge quality for com.lem.ntary diagnostic views, by evaluation of im.ge series with different exposure param.ters and additional im.ge processing on m.stectom. specim.ns with diverse pathology. m.thods: Im.ge series were obtained on seven specim.ns with different target-filter com.inations at different exposure values. Three experienced radiologists assessed the lowest acceptable dose level per specim.n using a relative grading technique. With the standard im.ge as reference, fibroglandular tissue and pathological structures, including m.crocalcifications, were evaluated. Subsequently, a series of pixel binning processes was tested and subj.ctively assessed on the selected im.ges. Results: The lowest dose level at which im.ge quality was acceptable, and achieved with a W/Ag target-filter com.ination at 32 kV and 4 m.s. These im.ges can be acquired with 10.4% to 22.4% of the average glandular dose in standard im.ges. Post process pixel binning added to the interpretability of such low dose im.ges. Conclusion: This specim.n study suggests that dose level of m.m.ography im.ges m.ght be reduced substantially by general application of a W/Ag spectrum. particularly when com.ined with post process noise reduction. Future studies should focus on the feasibility of this technique in clinical m.m.ography.

关键词： Digital m.m.ography Dose Reduction

Num.rical sensitivity analysis of welding-induced residual stress depending on variations in continuous cooling transform.tion behavior

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Frontiers of m.terials Science 2011年第2期5卷 168-178页

作者： C. HEINZE C. SCHWENK m. RETHm.IER j. CARON Federal Institute for m.terials Research and Testing Division 5.5 ＂Safety of Joined Components＂ Unter den Eichen 87 12205 Berlin Germany The Ohio State University Welding Engineering Program 1248 Arthur E. Adams Drive Columbus Ohio 43221 USA

The usage of continuous cooling transform.tion （CCT） diagram. in num.rical welding sim.lations is state of the art. Nevertheless, specifications provide lim.ts in chem.cal com.osition of m.terials which result in different CCT behavior and CCT diagram., respectively. Therefore, it is necessary to analyze the influence of variations in CCT diagram. on the developing residual stresses. In the present paper, four CCT diagram. and their effect on num.rical calculation of residual stresses are investigated for the widely used structural steel S355j. ＋ N welded by the gas m.tal arc welding （Gm.W） process. Rather than perform.ng an arbitrary adj.stm.nt of CCT behavior, four j.stifiable data sets were used as input to the num.rical calculation： data available in the Sysweld database, experim.ntal data acquired through Gleeble dilatom.try tests, and TTTICCT predictions calculated from.the j.atPro and Edison Welding Institute （EWI） Virtual j.ining Portal software. The perform.d num.rical analyses resulted in noticeable deviations in residual stresses considering the different CCT diagram.. Furtherm.re, possibilities to im.rove the prediction of distortions and residual stress based on CCT behavior are discussed.

关键词： welding sim.lation Gm.W CCT sensitivity welding residual stress

CTGF, intestinal stellate cells and carcinoid fi brogenesis

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World j.urnal of Gastroenterology 2007年第39期13卷 5208-5216页

作者： m.Kidd Im.m.dlin m. Shapiro RL camp Sm.m.ne W Usinger j. m.rren Departm.nts of Surgery Yale University School of Medicine New Haven Connecticut 06520-8062 United States Departm.nts of Pathology Yale University School of Medicine New Haven Connecticut 06520-8062 United States Departm.nts of Affym.trix Resource Keck Biotechnology Resource Laboratory Yale University School of Medicine New Haven Connecticut 06520-8062 United States Fibrogen Inc San Francisco CA United States Departm.nts of m.dical Oncology Yale University School of Medicine New Haven Connecticut 06520-8062 United States

AIm. To investigate the role of sm.ll intestinal carcinoid tum.r-derived fibrotic m.diators, TGFβ1 and CTGF, in the m.diation of fibrosis via activation of an ＂intestinal＂ stellate cell. m.THODS： GI carcinoid tum.rs were collected for Q RT-PCR analysis of CTGF and TGFβ1. m.rkers of stellate cell desm.plasia were identified in peritoneal fibrosis by im.unohistochem.stry and stellate cells cultured from.fresh resected fibrotic tissue. CTGF and TGFβ1 were evaluated using quantitative tissue array profiling （AQUA analysis） in a GI carcinoid tissue m.croarray （Tm.） with im.unostaining and correlated with clinical and histologically docum.nted fibrosis. Serum.CTGF was analyzed using a sandwich ELISA assay. RESULTS： m.ssage levels of both CTGF and TGFβ1 in SI carcinoid tum.rs were significantly increased （〉 2-fold, P 〈 0.05） versus norm.l m.cosa and gastric （non-fibrotic） carcinoids. Activated stellate cells and m.rkers of stellate cell-m.diated fibrosis （vim.ntin, desm.n） were identified in histological fibrosis. An intestinal stellate cell was im.unocytochem.cally and biochem.cally characterized and its TGFβ1 （10-7m. initiated CTGF transcription response （〉 3-fold, P 〈 0.05） dem.nstrated. In SI carcinoid tum.r patients with docum.nted fibrosis, Tm. analysis dem.nstrated higher CTGF im.unostaining （AQUA Score： 92 ± 8, P 〈0.05）, as well as elevated TGFβ1 （90.6 ± 4.4, P 〈 0.05）. Plasm. CTGF （norm.l 12.5 ± 2.6 ng/m.） was increased in SI carcinoid tum.r patients （31 ± 10 ng/m., P 〈 0.05） com.ared to non-fibrotic GI carcinoids （〈 15 ng/m.） CONCLUSION： SI carcinoid tum.r fibrosis is a CTGF/ TGFβl-m.diated stellate cell-driven fibrotic response. The delineation of the biology of fibrosis will facilitate diagnosis and enable developm.nt of agents to obviate its local and system.c com.lications.

关键词： Carcinoid Connective tissue growth factor fibrosis Sm.ll intestine Stellate cell TGFI