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Spoilt for Choice:New Options for Inhibitors of Strigolactone Signaling

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Molecular Plant 2019年第1期12卷 21-23页

作者： Mark T.waters School of Molecular Sciences The University of Western AustraliaPerth WA 6009Australia

Endogenously synthesized plant hormones direct the ordered growth of tissues,organs,and the overall plant body plan, thereby integrating external information with internal metabolism. Because plant hormones can have such dramatic and systemic effects on plant morphology,hormone activity has been a target of selective breeding for desirable plant traits,whether consciously or otherwise.

关键词： growth plan

Hyperhomocysteinemia as a potential contributor of colorectal cancer development in inflammatory bowel diseases: A review

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World Journal of Gastroenterology 2015年第4期21卷 1081-1090页

作者： Ammar Hassanzadeh Keshteli vickie E Baracos Karen L Madsen Department of Medicine University of AlbertaEdmontonAlberta T6G 2E1Canada Department of Oncology University of AlbertaCross Cancer InstituteEdmontonAlberta T6G 2E1Canada

Homocysteine is an amino acid generated metabolically by the S-adenosylmethionine-dependent transmethylation pathway. In addition to being a well-known independent risk factor for coronary heart disease, is also a risk factor for cancer. Patients suffering from inflammatory bowel diseases(IBD) including ulcerative colitis and Crohn's disease are at increased risk of developing colorectal cancer in comparison to healthy individuals. Furthermore, the risk of hyperhomocysteinaemia is significantly higher in IBD patients when compared with controls. In the present article, we review the mechanisms in which hyperhomocysteinemia may contribute to increased risk of colorectal cancer in IBD patients.

关键词： Hyperhomocysteinemia Colorectal cancer Inflammator

Seeing through the magnetite:Reassessing Eoarchean atmosphere composition from Isua(Greenland) ≥3.7 Ga banded iron formations

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Geoscience Frontiers 2017年第6期8卷 1233-1240页

作者： Allen P.Nutman vickie C.Bennett Clark R.L.Friend GeoQuEST Research Centre School of Earth and Environmental SciencesUniversity of WollongongWollongongNSW 2522Australia Research School of Earth Sciences Australian National UniversityCanberraACT 0200Australia Glendale TiddingtonOxonOX9 2LQUK

Estimates of early atmosphere compositions from metamorphosed banded iron formations(BIFs)including the well-studied ≥3.7 BIFs of the Isua supracrustal belt(Greenland)are dependent on knowledge of primary versus secondary Fe-mineralogical *** new observations from locally well preserved domains,we interpret that a previously assumed primary redox indicator mineral,magnetite,is secondary after sedimentary Fe-clays(probably greenalite)±*** ~3.7 Ga Isua BIF,pre-tectonic nodules of quartz+Fe-rich amphibole±calcite reside in a finegrained(≤100 μm)quartz+magnetite *** interpret the Isua nodule amphibole as the metamorphosed equivalent of primary Fe-rich clays,armoured from diagenetic oxidative reactions by early silica ***,in another low strain lacunae,~3.76 Ga BIF layering is not solid magnetite but instead fine-grained magnetite+quartz *** magnetite+quartz aggregates are interpreted as the metamorphosed equivalent of Fe-clay-rich layers that were oxidised during diagenesis,because they were not armoured by early *** almost all Isua BIF exposures,this evidence has been destroyed by strong ductile *** Fe-clays likely formed by abiotic reactions between aqueous Fe^(2+)and *** clays along with silica±carbonate were deposited below an oceanic Fe-chemocline as the sedimentary precursors of *** of the clays on the sea floor may have been by anaerobic oxidation of Fe^(2+),a mechanism compatible with iron isotopic data previously published on these *** new determinations of the primary redoxsensitive Fe-mineralogy of BIF significantly revise estimates of early Earth atmospheric oxygen and CO_2 content,with formation of protolith Fe-rich clays and carbonates compatible with an anoxic Eoarchean atmosphere with much higher CO_2 levels than previously estimated for Isua and in the present-day atmosphere.

关键词： Banded iron formation Eoarchean Early atmosphere Greenalite Magnetite

Convergent plate boundary environments for formation of≥3800 Ma mafic-ultramafic assemblages(Isua area,Greenland):Implications for early global geodynamics

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Geoscience Frontiers 2024年第3期15卷 119-136页

作者： Allen P.Nutman Clark R.L.Friend vickie C.Bennett School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK Research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss terrane on the south side of the Eoarchean Isua supracrustal belt,ultramafic rocks with relict abyssal peridotite mineralogy(Bennett et al.,2002;Friend et al.,2002;Nutman et al.,2007;Rollinson,2007;van de Löcht et al.,2020),layered gabbros with cumulate ultramafic rocks,basalts and associated siliceous sedimentary rocks were tectonically-imbricated,prior to and during intrusion of ca.3800 Ma *** with3800 Ma basalts in the Outer Arc Group of the nearby Isua supracrustal belt,the composition of all these mafic rocks(e.g.,Th-Hf-Nb systematics,high Th/Yb,Ba/Nb,Ba/Yb ratios and negative Nb and Ti anomalies)shows affinity with modern suprasubduction rocks whose genesis involved fluid fluxing of the upper ***,the majority of these samples have Ba/Nb and Ba/Yb values less than in modern island arc magmas,but similar to many backarc basin magmas(e.g.,Pearce and Stern,2006).It is unknown whether these ca.3800 Ma mafic rocks are,(i)arc rocks where the Ba/Nb and Ba/Yb signatures reflect lower surficial Ba in Eoarchean oceanic settings,or(ii)in direct comparison with Phanerozoic suites,these signatures reflect a back-arc setting with interplay between fluid fluxing and decompressional *** tectonic intercalation of upper mantle with lower and upper crustal rocks,combined with the fluid-fluxing influences seen in chemistry of all the mafic rocks is best accommodated in a compressional Eoarchean convergent plate boundary setting within a mobile-lid *** stagnant lid scenarios of crust formation,if operative,must have co-existed or alternated with mobile-lid regimes by 3800 Ma.

关键词： Eoarchean Fluid-fluxing Plate tectonics Suprasubduction Crustal evolution

Sensitivity Analysis and Computations of the Time RelaxationModel

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Advances in Applied Mathematics and Mechanics 2015年第1期7卷 89-115页

作者： Monika Neda Fran Pahlevani Jiajia waters Department of Mathematics University of NevadaLas VegasNV 89154USA Department ofMathematics Penn State University-Abington CollegePA 19001USA

This paper presents a numerical study of the sensitivity of a fluid model known as time relaxation model with respect to variations of the time relaxation coefficient *** sensitivity analysis of this model is utilized by the sensitivity equation method and uses the finite element method along with Crank Nicolson method in the fully discretization of the partial differential *** present a test case in support of the sensitivity convergence and also provide a numerical comparison between two different strategies of computing the sensitivity,sensitivity equation method and forward finite differences.

关键词： Sensitivity analysis time relaxation model Navier-Stokes equations finite element method.

Physicochemical aspects of allanite flotation

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Journal of Rare Earths 2014年第5期32卷 476-486页

作者： Adam Jordens Chris Marion Olga Kuzmina Kristian E.waters Department of Mining and Materials Engineering McGill University

This paper investigated the physicochemical properties of allanite, a RE-silicate, by measuring zeta potential in the absence and presence of three different flotation collectors （benzohydroxamic acid, sodium oleate and dodecylamine）. This data was then verified by microflotation experiments and with bubble-particle attachment pictures. The investigated properties of allanite were com- pared to those of quartz, a common gangue mineral in many RE deposits. The results of this work indicated that only dodecylamine was able to achieve a selective separation of allanite and quartz. This was accomplished by lowering the dodecylamine dosage so that only quartz was recovered by microflotation.

关键词： allanite flotation surface chemistry zeta potential bubble-particle attachment rare earths

KAI2-and MAX2-Mediated Responses to Karrikins and Strigolactones Are Largely Independent of HY5 in Arabidopsis Seedlings

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Molecular Plant 2013年第1期6卷 63-75页

作者： Mark T. waters Steven M. Smitht Plant Energy Biology University of Western Australia Crawley Western Australia 6009 Australia School of Chemistry and Biochemistry University of Western Australia Crawley Western Australia 6009 Australia

Karrikins are butenolide compounds released from burning vegetation that stimulate seed germination and enhance seedling photomorphogenesis. Strigolactones are structurally similar plant hormones that regulate shoot and root development, and promote the germination of parasitic weed seeds. In Arabidopsis, the F-box protein MAX2 is required for responses to karrikins and strigolactones, and the a/~ hydrolase KAI2 is necessary for responses to karrikins. Both MAX2 and KAI2 are essential for normal light-dependent seedling development. The bZIP transcription factor HY5 acts downstream of multiple photoreceptors and promotes photomorphogenesis, but its relationship with MAX2 and KAI2 in terms of seedling development and responses to karrikins and strigolactones is poorly defined. Here, we dem- onstrate that HY5 action is genetically separable from that of MAX2 and KAI2. While by5 mutants have weak hypoco- tyl elongation responses to karrikins and the artificial strigolactone GR24, they have normal transcriptional responses, suggesting that HY5 is not involved in perception or action of karrikins or strigolactones. Furthermore, we show that overexpression of KAI2 is sufficient to enhance responses to both karrikins and GR24 in wild-type seedlings, and that KAI2 overexpression partially suppresses the hy5 long hypocotyl phenotype. These results suggest that KAI2 and MAX2 define a regulatory pathway that largely operates independently of HY5 to mediate seedling responses to abiotic signals such as smoke and light.

关键词： smoke karrikin strigolactone KAI2 HY5 photomorphogenesis.

Development and optimization of thermal contrast amplification lateral flow immunoassays for ultrasensitive HIV p24 protein detection

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Microsystems & Nanoengineering 2020年第1期6卷 683-693页

作者： Li Zhan Timothy Granade Yilin Liu Xierong Wei Ae Youngpairoj vickie Sullivan Jeff Johnson John Bischof Department of Mechanical Engineering University of MinnesotaMinneapolisMNUSA Centers for Disease Control and Prevention AtlantaGAUSA Department of Biomedical Engineering University of MinnesotaMinneapolisMNUSA

Detection of human immunodeficiency virus(HIV)p24 protein at a single pg/ml concentration in point-of-care(POC)settings is important because it can facilitate acute HIV infection diagnosis with a detection sensitivity approaching that of laboratory-based ***,the limit of detection(LOD)of lateral flow immunoassays(LFAs),the most prominent POC diagnostic platform,falls short of that of laboratory protein detection methods such as enzyme-linked immunosorbent assay(ELISA).Here,we report the development and optimization of a thermal contrast amplification(TCA)LFA that will allow ultrasensitive detection of 8 pg/ml p24 protein spiked into human serum at POC,approaching the LOD of a laboratory *** achieve this aim,we pursued several innovations as follows:(a)defining a new quantitative figure of merit for LFA design based on the specific to nonspecific binding ratio(BR);(b)using different sizes and shapes of gold nanoparticles(GNPs)in the systematic optimization of TCA LFA designs;and(c)exploring new laser wavelengths and power regimes for TCA LFA ***,we optimized the blocking buffer for the membrane and running buffer by quantitatively measuring the BR using a TCA *** TCA reader interprets the thermal signal(i.e.,temperature)of GNPs within the membrane when irradiated by a laser at the plasmon resonance wavelength of the *** process results in higher detection and quantitation of GNPs than in traditional visual detection(i.e.,color intensity).Further,we investigated the effect of laser power(30,100,200 mW),GNP size and shape(30 and 100 nm gold spheres,150 nm gold-silica shells),and laser wavelength(532,800 nm).Applying these innovations to a new TCA LFA design,we demonstrated that 100nm spheres with a 100 mW 532 nm laser provided the best performance(i.e.,LOD=8pg/ml).This LOD is significantly better than that of the current colorimetric LFA and is in the range of the laboratory-based p24 *** summary,this TCA LFA for p24 prote

关键词： optimization approaching flow

Predictive value of symptoms and demographics in diagnosing malignancy or peptic stricture

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World Journal of Gastroenterology 2012年第32期18卷 4357-4362页

作者： Iain A Murray Joanne Palmer Carolyn waters Harry R Dalton Department of Gastroenterology Royal Cornwall HospitalTruroCornwall TR1 3LJUnited Kingdom Research and Development Knowledge SpaRoyal Cornwall HospitalTruroCornwall TR1 3LJUnited Kingdom

AIM:To determine which features of history and demographics predict a diagnosis of malignancy or peptic stricture in patients presenting with ***:A prospective case-control study of 2000 consecutive referrals(1031 female,age range:17-103 years) to a rapid access service for dysphagia,based in a teaching hospital within the United Kingdom,over 7 *** service consists of a nurse-led telephone triage followed by investigation(barium swallow or gastroscopy),if appropriate,within 2 *** regression analysis of demographic and clinical variables was *** includes age,sex,duration of dysphagia,whether to liquids or solids,and whether there are associated features(reflux,odynophagia,weight loss,regurgitation).We determined odds ratio(OR) for these variables for the diagnoses of malignancy and peptic *** determined the value of the Edinburgh Dysphagia Score(EDS) in predicting cancer in our *** logistic regression was performed and P 73 years,OR 1.1-3.3,age 73 years 11.8%,P 26 wk 2.5%,P < 0.0005),progressive symptoms(OR 1.3-2.6:progressive 14.8%,int

关键词： Dysphagia Deglutition disorders Esophageal neoplasms Esophageal stenosis Gastroscopy Barium swallow Predictive value of tests