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Testing experimentally the effect of soil resource mobility on plant competition

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Journal of Plant Ecology 2014年第3期7卷 276-286页

作者： Stefanie Wilberts Matthias Suter Nina Walser Peter J.edwards Harry Olde Venterink Dieter Ramseier Department of Biology/Chemistry Division of EcologyUniversity of OsnabrückBarbarastrasse 13Osnabrück 49076Germany Forage Production and Grassland Agroscope Reckenholz-TänikonReckenholzstrasse 1918046 ZurichSwitzerland Institute of Integrative Biology ETH ZurichUniversitätstrasse 16Zürich 8092Switzerland Plant Biology and Nature Management Vrije Universiteit BrusselPleinlaan 21050 BrusselsBelgium

Aims The volume of soil beyond a plant’s roots from which that plant is able to acquire a particular nutrient depends upon the mobility of that nutrient in the *** this reason it has been hypothesized that the strength of competitive interactions between plants vary with soil nutrient *** aimed to provide an experimental test of this *** We devised two experimental systems to investigate specifically the effect of nutrient transport rates upon intraspecific *** the first,the exchange of rhizosphere water and dissolved nutrients between two connected pots,each containing one plant,was manipulated by alternately raising and lowering the *** the second experiment,the roots systems of two competing plants were separated by partitions of differing porosity,thereby varying the plants’access to water and nutrients in the other plant's *** this second experiment,we also applied varying amounts of nutrients to test whether higher nutrient input would reduce competition when competition for light is avoided,and applied different water levels to affect nutrient concentrations without changing nutrient *** findings In both experiments,lower mobility reduced competitive effects on plant biomass and on relative growth rate(RGR),as *** the second experiment,however,competition was more intense under high nutrient input,suggesting that low nutrient supply rates reduced the strength of the superior *** effects on RGR were only evident under the low water level,suggesting that under lower nutrient concentrations,competitive effects might be less *** together,our results provide the first direct experimental evidence that a reduction in nutrient mobility can reduce the intensity of competition between plants.

关键词： belowground competition nutrient transport soil water relative growth rate

The decomposition rate of the organic carbon content of suspended particulate matter in the tropical seagrass meadows

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Acta Oceanologica Sinica 2021年第8期40卷 44-52页

作者： A'an Johan Wahyudi Karlina Triana Afdal Afdal Hanif Budi Prayitno edwards Taufiqurrahman Hanny Meirinawati Rachma Puspitasari Lestari Lestari Suci Lastrini Research Center for Oceanography Indonesian Institute of Sciences(LIPI)Jakarta 14430Indonesia

In terms of downward transport,suspended particulate matter(SPM)from marine or terrigenous sources is an essential contributor to the carbon *** mesoscale environments such as seagrass ecosystems,SPM flux is an essential part of the total carbon budget that is transported within the *** assessing the total SPM transport from water column to sediment,potential carbon burial can be ***,SPM may decompose or reforming aggregate during transport,so estimating the vertical flux without knowing the decomposition rate will lead to over-or underestimation of the total carbon *** this paper presents the potential decomposition rate of the SPM in seagrass ecosystems in an attempt to elucidate the carbon dynamics of *** was collected from the seagrass ecosystems located at Sikka and Sorong in *** situ experiments using SPM traps were conducted to assess the vertical downward flux and decomposition rate of *** isotopic profile of SPM was measured together with organic carbon and total nitrogen *** results show that SPM was transported to the bottom of the seagrass ecosystem at a rate of up to(129.45±53.79)mg/(m^(2)·h)(according to carbon).Considering the whole period of inundation of seagrass meadows,SPM downward flux reached a maximum of 3096 mg/(m^(2)·d)(according to carbon).The decomposition rate was estimated at from 5.9μg/(mg·d)(according to carbon)to 26.6μg/(mg·d)(according to carbon).Considering the total downward flux of SPM in the study site,the maximum decomposed SPM was estimated 39.9 mg/(m^(2)·d)(according to carbon)and 82.6 mg/(m^(2)·d)(according to carbon)for study site at Sorong and Sikka,*** decomposed SPM can be 0.6%–2.7%of the total SPM flux,indicating that it is a small proportion of the total *** seagrass ecosystems of Sorong and Sikka SPM show an autochthonous tendency with the primary composition of marine-end materials.

关键词： carbon dynamic biogeochemistry coastal ecosystem particulate matter

An annually laminated stalagmite from the eastern Qinghai-Tibetan Plateau provides evidence of climate instability during the early MIS5e in the Asian summer monsoon

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Science China Earth Sciences 2023年第5期66卷 1147-1164页

作者： Tao GAO Pingzhong ZHANG Hai CHENG Leilei ZHANG Xinhu LI Hongyu SHI Wei JIA Youfeng NING Hanying LI R.Lawrence edwards Key Laboratory of Mineral Resources in Western China(Gansu Province)and School of Earth Sciences Lanzhou UniversityLanzhou730000China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an710054China Department of Earth Sciences University of MinnesotaMinneapolis55455USA

The Marine Isotope Stage(MIS5e)is characterized by a warmer climate than that of the pre-industrial period,and serves as an analog for the Current Warm Period(CWP).However,uncertainties persist regarding its climatic ***,we retrieved a stalagmite(WXB075)from Wanxiang Cave in the eastern Qinghai-Tibetan Plateau,and employed abs-olute^(230)Th dating and relative annual layer data to establish a high-precision chronological framework for reconstructing the history of the Asian summer monsoon(ASM)and environmental evolution during early MIS5e with multiple *** findings indicate that the annually laminated stalagmite was formed during Cooling Event 27(C27).The deposition of WXB075 experienced a hiatus(~125.58 ka BP)due to a significant cooling event in the North Atlantic,which may be linked to the unstable climate in the Northern ***,the impact of meltwater discharge in high northern latitudes results in a two-phase evolution of the ASM,i.e.,an initial weaker stage followed by a gradual increase(with exception of deposition hiatus).The climatic instability of ASM is generally characterized by a quasi-60 year cycle that affects vegetation conditions,biological productivity,and karst hydroclimate ***,the increase in meltwater and decrease in temperature in the Northern Hemisphere have led to a weakened ASM and subsequent reduction in ***,vegetation degradation above the cave has occurred along with a slowdown of karst *** vegetation conditions,organic matter content,and wet/drought of the karst hydroclimate were affected by both the large-scale monsoon circulation and local environment during extreme weakening(strengthening)of the monsoon when high-frequency climatic events of ASM occurred.A comparison ofδ^(18)O records between early MIS5e and the past 2000 years reveals that the climate during early MIS5e differed significantly from that of CWP,Medieval Warm Period(MWP),and Dark Age Co

关键词： Eastern Qinghai-Tibetan Plateau Climate instability Wanxiang Cave stalagmite Asian summer monsoon Environmental response Deposition hiatus

Chemical composition and in vitro fermentation characteristics of high sugar forage sorghum as an alternative to forage maize for silage making in Tarim Basin, China

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Journal of Integrative Agriculture 2016年第1期15卷 175-182页

作者： ZHANG Su-jiang Abdul Shakoor Chaudhry Diky Ramdani Amerjan Osman GUO Xue-feng Grant Raymond edwards Long Cheng Key Laboratory of Tarim Animal Husbandry Science and Technology College of Animal Science Tarim University School of Agriculture Food and Rural Development Newcastle University Faculty of Animal Husbandry University Padjadjaran College of Plant Science and Technology Tarim University Faculty of Agriculture & Life Sciences Lincoln University

The chemical composition, mineral profile and in vitro fermentation characteristics of maize （MZ）, high sugar forage sorghum （HS） and forage sorghum （FS）, and silages made from each forage type were measured. The MZ and MZ silage （MZS） had higher crude protein, starch and ether extract contents than both sorghum forages and sorghum silages. HS had higher ash and water-soluble carbohydrate concentrations than FS and MZ. MZ, MZS, HS and HS silage （HSS） had lower neutral detergent fibre, acid detergent fibre and acid detergent lignin than FS and FS silage （FSS）. FSS had higher dry matter （DM） and pH than MZS and HSS. HSS contained higher concentrations of P and K than FSS and MZS. MZS and HSS had higher in vitro dry matter and organic matter digestibility, CH4 production, total volatile fatty acids, acetate and propionate than FSS. pH was higher for FSS than for HSS, and ammonia was lower for HSS than for MZS and FSS. HSS had higher gas production than MZS and FSS after 2, 4, 6 and 8 h incubation. MZS had higher gas production than HSS and FSS after 26 and 28 h of incubation. The results indicate that HS may substitute for MZ to make good quality silage. However, animal studies are needed to assess the acceptability and feeding values of HSS vs. MZS for ruminant production.

关键词： high sugar forage sorghum maize silage digestibility methane gas production

Portal vein ligation accelerates tumor growth in ligated,but not contralateral lobes

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World Journal of Gastroenterology 2010年第30期16卷 3816-3826页

作者： Nozomu Sakai Callisia N Clarke Rebecca Schuster John Blanchard Amit D Tevar Michael J edwards Alex B Lentsch Department of Surgery University of Cincinnati231 Albert Sabin WayCincinnatiOH 45267-0558United States

AIM: To investigate the mechanisms of liver growth and atrophy after portal vein ligation (PVL) and its effects on tumor growth. METHODS: Mice were subjected to PVL, partial hepatectomy, or sham surgery. The morphological alterations, activation of transcription factors, and expression of cytokines and growth factors involved in liver regeneration were evaluated. In a separate set of experiments, murine colorectal carcinoma cells were injected via the portal vein and the effect of each operation on liver tumor growth was studied. RESULTS: Liver regeneration after PVL and partial hepatectomy were very similar. In ligated lobes, various cytokines, transcription factors and regulatory factors were signifi cantly upregulated compared to nonligated lobes after PVL. Atrophy in ligated lobes was a result of early necrosis followed by later apoptosis. Tumor growth was signifi cantly accelerated in ligated compared to non-ligated ***: Tumor growth was accelerated in ligated liver lobes and appeared to be a result of increased growth factor expression.

关键词： Portal vein ligation Tumor growth Growth factor Atrophy Apoptosis

Standards of liver cirrhosis care in Central Australia

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World Journal of Hepatology 2022年第3期14卷 559-569页

作者： Sreecanth S Raja Robert G Batey Suzanne edwards Hein H Aung Department of Gastroenterology Alice Springs HospitalAlice Springs 0870Northern TerritoryAustralia Department of Medicine Alice Springs HospitalAlice Springs 0870Northern TerritoryAustralia Department of Statistician School of Public HealthUniversity of AdelaideAdelaide 5000South AustraliaAustralia

BACKGROUND Liver cirrhosis and hepatocellular carcinoma(HCC)are highly prevalent in Australia’s Northern *** factors include high levels of alcohol consumption,viral hepatitis and metabolic *** Aboriginal residents form a significant proportion of the Central Australian population and present a challenge to traditional models of liver *** surveillance and variceal screening are core components of liver cirrhosis *** To assess participation in HCC and variceal surveillance programmes in a Central Australian liver cirrhosis patient *** Retrospective cohort study of patients with liver cirrhosis presenting to Alice Springs Hospital,Australia between January 1,2012 and December 31,*** data,disease severity,attendance at hepatology clinics,participation in variceal and/or HCC surveillance programmes was *** analyses were conducted to assess factors associated with two independent outcomes:Participation in HCC and variceal *** Of 193 patients were identified.82 patients(42.4%)were female.154 patients(80%)identified as *** Model for End-stage Liver Disease Score at diagnosis was *** was the most common cause of *** patients were younger than non-Aboriginal patients(48.4 years vs 59.9 years,P<0.001).There were similar rates of excess alcohol intake(72.6%vs 66.7%,P=0.468)and obesity(34.5%vs 38.4%,P=0.573 across non-Aboriginal and Aboriginal cohorts.20.1%of patients took part in HCC surveillance and 42.1%of patients completed variceal *** patients were less likely to engage with either HCC surveillance(OR:0.38,95%CI:0.16-0.9,P=0.025)or undergo variceal screening(OR:0.31,95%CI:0.14-0.65,P=0.002).CONCLUSION HCC or variceal surveillance programmes had less uptake amongst Aboriginal *** emphasis needs to be placed on eliminating cultural obstacles to accessing hepatology services.

关键词： Viral hepatitis Cirrhosis Hepatocellular carcinoma Alcoholic liver disease Central australia

Case report:simultaneous femtosecond laser astigmatic keratotomy and toric intraocular lens implantation in femtosecond laser-assisted cataract surgery in a patient with surgically induced high corneal astigmatism

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Annals of Eye Science 2022年第4期7卷 69-76页

作者： Yan Guo Heather edwards Mark Woodward Tyrone Curtis Gresham Kayla Morgan Hampton Roads Eye Associates Riverside Medical GroupHamptonVAUSA Hampton Surgical Center Riverside Medical GroupHamptonVAUSA

Background:Femtosecond laser astigmatic keratotomy(FSAK)and toric intraocular lens(IOL)implantation have been studied individually for comparison to treat astigmatism at cataract *** report a case of surgically induced high corneal astigmatism by laser thermal keratoplasty(LTK)in a patient with cataract who was successfully treated with simultaneous combination of FSAK and toric IOL implantation with femtosecond laser-assisted cataract surgery(FLACS).This is the first report of both procedures combined simultaneously,with or without history of *** Description:A 68-year-old male presented with a history of LTK with two enhancements each eye in 2004,with subsequent surgically induced high corneal astigmatism,and with age-related nuclear cataract of both *** master demonstrated+7.71 diopters of astigmatism at 163 degree right eye and+3.29 diopters of astigmatism at 4 degree left *** extensive discussion of the risks and benefits,the patient agreed to undergo FLACS with FSAK with two 61 degrees of relaxation incisions(RIs)and toric IOL(Alcon SN6AT9)right eye;FLACS with toric IOL(Alcon SN6AT7)alone left *** 2-year follow-up,uncorrected visual acuity was 20/30 right eye,20/25 left *** best corrected visual acuity was 20/25(+0.25+1.00 axis 21)right eye and 20/20(plano+0.25 axis 90)left eye;his best corrected near visual acuity was J1+with add+2.50 diopters right eye and left ***:Patients with age-related cataract and LTK induced high corneal astigmatism can hardly be sufficiently treated with FSAK or toric IOL alone at the time of cataract *** effective way is to combine large FSAK and toric IOL of the highest cylindrical power of T9,in our case,simultaneously,which can achieve an excellent long term visual outcome.

关键词： High corneal astigmatism[induced by laser thermal keratoplasty(LTK)] femtosecond laser astigmatic keratotomy(FSAK) toric intraocular lens implantation(IOL implantation) femtosecond laser-assisted cataract surgery(FLACS) case report

Chemical Reaction Route Selection Based on Green Chemical Engineering

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Chinese Journal of Chemical Engineering 2004年第5期12卷 662-667页

作者：何潮洪葛挺峰 David W.edwards Department of Chemical Engineering Zhejiang University Hangzhou 310027 China Department of Chemical Engineering Loughborough University Leicestershire LE11 3TU UK

In the preliminary stage of chemical process design, the choice of chemical reaction route is the key design decision, and the concepts of atom utilization and environmental quotient have become extremely useful tools. However, the waste quality such as chemical toxicity and other engineering factors have not been taken into account. Therefore, a synthetic route selection index, Iroute, is proposed to determine the suitability of a chemical route in this paper. Iroute considers the effects of 'extended atom economy', material renewability, chemical characteristics and some engineering factors. The extended atom economy concept regards not only the value of the desired product but also the value of byproducts. The methodology by using Iroute to compare different routes is illustrated in case study of cyclohexanone oxime and acrylonitrile manufacture.

关键词： green design reaction route selection atom economy product chain

Cardiac Transplantation : The Columbia University Medical Center / New York-Presbyterian Hospital Manual 1

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