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Net ecosystem carbon exchange for Bermuda grass growing in mesocosms as affected by irrigation frequency

Pedosphere 2022年第3期32卷 393-401页

作者： Yuan LI Gabriel *** Timothy J.CLOUGH john e.HUNT David WHITeHeAD Department of Soil and Physical Sciences Lincoln UniversityLincoln 7647(New Zealand) Manaaki Whenua-Landcare Research P.O.Box 69040Lincoln 7640(New Zealand) State Key Laboratory of Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020(China) Soil Biology Group Wageningen University and ResearchP.O.Box 47Wageningen 6700 AA(The Netherlands)

Intensification of grazed grasslands following conversion from dryland to irrigated farming has the potential to alter ecosystem carbon(C)cycling and affect components of carbon dioxide(CO_(2))exchange that could lead to either net accumulation or loss of soil *** there are many studies on the effect of water availability on biomass production and soil C stocks,much less is known about the effect of the frequency of water inputs on the components of CO_(2)*** grew Bermuda grass(Cynodon dactylon L.)in mesocosms under irrigation frequencies of every day(I_(1) treatment,30 d),every two days(I_(2) treatment,12 d),every three days(I_(3) treatment,30 d),and every six days(I_(6) treatment,18 d,after I_(2) treatment).Rates of CO_(2)exchange for estimating net ecosystem CO_(2)exchange(F_(N)),ecosystem respiration(R_(e)),and soil respiration(R_(S))were measured,and gross C uptake by plants(F_(G))and respiration from leaves(R_(L))were calculated during two periods,1–12 and 13–30 d,of the 30-d *** the first 12 d,there were no significant differences in cumulative F_(N)(mean±standard deviation,61±30 g C m^(-2),n=4).During the subsequent 18 d,cumulative F_(N) decreased with decreasing irrigation frequency and increasing cumulative soil water deficit(W),with values of 70±22,60±16,and 18±12 g C m^(-2) for the I_(1),I_(3),and I_(6) treatments,*** were similar decreases in F_(G),R_(e),and R_(L) with increasing W,but differences in R_(S) were not *** of the C_(4) grass growing in a C_(3)-derived soil enabled partitioning of R_(S) into its autotrophic(R_(A))and heterotrophic(R_(H))components using a^(13)C natural abundance isotopic technique at the end of the experiment when differences in cumulative W between the treatments were the *** values of R_(H) and its percentage contributions to R_(S)(43%±8%,42%±8%,and 8%±5%for the I_(1),I_(3),and I_(6) treatments,respectively)suggested that R_(H) remained unaffected across a wide

关键词： ^(13)C natural abundance CO_(2)exchange N_(2)O emission soil heterotrophic respiration water deficit

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High-Con cent rat ion electrosynthesis of Formic Acid/Formate from CO_(2):Reactor and electrode Design Strategies

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energy & environmental Materials 2023年第6期6卷 141-157页

作者： Yizhu Kuang Hesamoddin Rabiee Lei Ge Thomas e.Rufford Zhiguo Yuan john Bell Hao Wang Centre for Future Materials University of Southern QueenslandSpringfieldQLD 4300Australia Australian Centre for Water and environmental Biotechnology(ACWeB formerly AWMC)The University of QueenslandSt.LuciaQLD 4072Australia School of Chemical engineering The University of QueenslandBrisbaneQLD 4072Australia

The electrochemical CO_(2)reduction reaction(CO_(2)RR),driven by renewable energy,provides a potential carbon-neutral avenue to convert CO_(2)into valuable fuels and *** of CO_(2)into formic acid/formate is considered one of the economical and feasible methods,owing to their high energy densities,and ease of distribution and *** separation of formic acid/formate from the reaction mixtures accounts for the majority of the overall CO_(2)RR process cost,while the increment of product concentration can lead to the reduction of separation cost,*** this paper,we give an overview of recent strategies for highly concentrated formic acid/formate products in CO_(2)***_(2)RR is a complex process with several different products,as it has different intermediates and reaction ***,this review focuses on recent study strategies that can enhance targeted formic acid/formate yield,such as the all-solid-state reactor design to deliver a high concentration of products during the reduction of CO_(2)in the ***,some novel electrolyzers are introduced as an engineering strategy to improve the concentration of the formic acid/formate and reduce the cost of downstream ***,the design of planar and gas diffusion electrodes(GDes)with the potential to deliver high-concentration formic acid/formate in CO_(2)RR is ***,the existing technological challenges are highlighted,and further research recommendations to achieve high-concentration products in CO_(2)*** review can provide some inspiration for future research to further improve the product concentration and economic benefits of CO_(2)RR.

关键词： electrochemical CO_(2)reduction reaction electrode design formic acid/formate high-concentration reactor design

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Bedrock aquifers and population growth in the Denver Basin, Colorado, USA

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episodes 2007年第2期30卷 115-118页

作者： john e. Moore Robert G. Raynoldse Marieke Dechesne U.S. Geological Survey Denver Colorado USA. Denver Museum of Nature ＆ Science Denver Colorado USA.

The Denver Basin bedrock aquifer system consists of Tertiary and Cretaceous age sedimentary rocks known as the Dawson, Denver, Arapahoe and Laramie-Fox Hills aquifers. The number of bedrock wells has increased from 12,000 in 1985 to over 33,700 in 2001 and the withdrawal of groundwater has caused water level declines in excess of 75 meters. Water level declines now range from 3 to 12 meters per year in the critical Arapahoe Aquifer. The groundwater supplies were once thought to be sufficient for 100 years but there is concern that they may be depleted in 10 to 15 years in areas on the west side of the basin. Groundwater is being mined from the aquifer system because the withdrawal through wells exceeds the rate of recharge. Increased groundwater withdrawal will cause further water level declines, increased costs to pump groundwater, and reduced yield from existing wells. In the Denver Basin, hydrologists have some capability to monitor declines in water levels for the Arapaho Aquifer, but generally have a limited ability to monitor water use. More complete and accurate water use data are needed to predict groundwater longevity for the Arapahoe Aquifer. The life of the Arapahoe Aquifer can be extended with artificial recharge using imported surface water, water reuse, restrictions on lawn watering, well permit restrictions and other conservation measures. Availability of groundwater may limit growth in the Denver Basin over the next 20 years unless residents are willing to pay for additional new sources of supply.

关键词：基岩含水层丹佛盆地美国

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基于冗余度分析的海上风电场可靠性提高方法(英文)

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电力系统自动化 2010年第4期34卷 84-91页

作者：杨进 john O' ReILLY john e. FLeTCHeR 华北电力大学电力工程系河北省保定市071003 Department of electronics and electrical engineering University of GlasgowG12 8LT英国 Department of electronic and electrical engineering University of StrathclydeG1 1XW英国

讨论了基于冗余度分析的海上风电场内部电能收集系统和传输系统可靠性提高方法。定义了风电场低压/中压网络与高压传输系统的冗余度。在同时考虑可靠性和经济性的前提下,提出了系统进行风电场冗余设计的方法。采用大型海上风电场设计实... 详细信息

讨论了基于冗余度分析的海上风电场内部电能收集系统和传输系统可靠性提高方法。定义了风电场低压/中压网络与高压传输系统的冗余度。在同时考虑可靠性和经济性的前提下,提出了系统进行风电场冗余设计的方法。采用大型海上风电场设计实例对所提方法进行了验证,得到了最优冗余设计结果。该方法对于提高具有复杂拓扑的大型海上风电场电能收集和传输系统的可靠性具有一定应用优势。

关键词：大型海上风电场冗余度可靠性电能收集系统传输系统

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evaluation of method performance for osteometric sorting of commingled human remains

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Forensic Sciences Research 2018年第4期3卷 343-349页

作者： john e.Byrd Carrie B.LeGarde Laboratory Defense POW/MIA Accounting AgencyJoint Base Pearl Harbor-HickamHIUSA

evaluation of method performance involves the consideration of numerous factors that can contribute to error.A variety of measures of performance can be borrowed from the signal detection literature and others are drawn from statistical *** article demonstrates the principles of performance evaluation by applying multiple measures to osteometric sorting models for paired elements run against data from known *** indicate that false positive rates are close,on average,to expected *** assemblage size grows,the false positive rate becomes unimportant and the false negative rate becomes *** disparity among the commingled individuals plays a significant role in method performance,showing that case-specific circumstances(*** size and size disparity)will determine method power.

关键词： Forensic sciences forensic anthropology statistics test method method performance error signal detection osteometric sorting

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Dietary analysis of Homonota darwini (Squamata:Gekkonidae) in Northern Patagonia

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Current Zoology 2010年第4期56卷 406-410页

作者： Marcelo e.KUN Carla PIANTONI john D.KReNZ Nora R.IBARGüeNGOYTíA Departamento de Zoología Centro Regional Universitario Bariloche Universidad del Comahue Unidad Postal Universidad del Comahue Smithsonian Institution NHB MRC 163 Department of Biological Sciences Minnesota State University Departamento de Zoologia Centro Regional Universitario Bariloche Universidad del Comahue Unidad Postal Universidad del Comahue Instituto de Investigación en Diversidad y Medio Ambiente (INIBIOMA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICeT)

Our study investigated the diet of the southernmost gecko in the world, Homonota darwini. Fifty-three specimens were captured during spring and summer in four locations in Patagonia, Argentina. The stomach contents of the specimens were identified, and we tbund that prey consisted of six main groups： Coleoptera, Hymenoptera, Homoptera and Araneae, and the adults and larvae of moth Lepidoptera. Lepidoptera was the major dietary component. The presence of ants and moths as common prey suggests an ambush feeding strategy. In spring, females consumed more ants than males although no other dietary differences between males and females were evident. We tbund nine geckos with empty stomachs and six parasitized by nematodes. Presence of empty stomachs corroborates previous observations of other nocturnal geckos and non-gecko lizards. Reduced foraging success of nocturnal lizards could be due to difficulty in prey detection due to dim light, reduced or erratic activity of insect prey at night, or shorter activity times of geckos relative to diurnal success. Sex and season were not associated with the incidence of empty stomachs. Principal component analysis showed that four food alternatives correlated with season. The constraint of nocturnality, coupled with low night-time temperatures restricting feeding to only a few hours after sunset, appear to have caused a generality of diet which may limit energy acquisition. We conclude that H. darwini is an arthropod generalist and likely an ambush forager, as are many other nocturnal gekkonids

关键词： Nocturnal lizards Diet Gekkonidae Patagonia PCA

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Liver iron transport

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World Journal of Gastroenterology 2007年第35期13卷 4725-4736页

作者： Ross M Graham Anita CG Chua Carly e Herbison john K Olynyk Debbie Trinder School of Medicine and Pharmacology Fremantle HospitalUniversity of Western AustraliaFremantleWestern AustraliaAustralia School of Medicine and Pharmacology Fremantle HospitalUniversity of Western AustraliaFremantleWestern AustraliaAustralia Western Australian Institute for Medical ResearchNedlandsWestern AustraliaAustralia

The liver plays a central role in iron metabolism. It is the major storage site for iron and also expresses a complex range of molecules which are involved in iron transport and regulation of iron homeostasis. An increasing number of genes associated with hepatic iron transport or regulation have been identified. These include transferrin receptors （TFRI and 2）, a ferrireductase （STeAP3）, the transporters divalent metal transporter-1 （DMT1） and ferroportin （FPN） as well as the haemochromatosis protein, HFe and haemojuvelin （HJV）, which are signalling molecules. Many of these genes also participate in iron regulatory pathways which focus on the hepatic peptide hepcidin. However, we are still only beginning to understand the complex interactions between liver iron transport and iron homeostasis. This review outlines our current knowledge of molecules of iron metabolism and their roles in iron transport and regulation of iron homeostasis.

关键词： Liver Iron homeostasis Iron uptake Iron release Iron transporters Hereditary haemochromatosis

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Perinatal and early life risk factors for inflammatory bowel disease

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World Journal of Gastroenterology 2011年第6期17卷 743-749页

作者： Stephen e Roberts Clare J Wotton john G Williams Myfanwy Griffith Michael J Goldacre College of Medicine Swansea University Unit of Health-Care epidemiology Department of Public HealthUniversity of Oxford

AIM:To investigate associations between perinatal risk factors and subsequent inflammatory bowel disease (IBD) in children and young ***:Record linked abstracts of birth registrations,maternity,day case and inpatient admissions in a defined population of southern *** of 20 perinatal factors relating to the maternity or the birth:maternal age,Crohn's disease (CD) or ulcerative colitis (UC) in the mother,maternal social class,marital status,smoking in pregnancy,ABO blood group and rhesus status,pre-eclampsia,parity,the infant's presentation at birth,caesarean delivery,forceps delivery,sex,number of babies delivered,gestational age,birthweight,head circumference,breastfeeding and Apgar scores at one and five ***:Maternity records were present for 180 children who subsequently developed *** analysis showed increased risks of CD among children of mothers with CD (P=0.011,based on two cases of CD in both mother and child) and children of mothers who smoked during *** analysis confirmed increased risks of CD among children of mothers who smoked (odds ratio=2.04,95% CI=1.06-3.92) and for older mothers aged 35+ years (4.81,2.32-9.98).Multivariate analysis showed that there were no significant associations between CD and 17 other perinatal risk factors *** also showed that,for UC,there were no significant associations with the perinatal factors ***:This study shows an association between CD in mother and child;and elevated risks of CD in children of older mothers and of mothers who smoked.

关键词： Crohn's disease Ulcerative colitis Perinatal risk factors Record linkage

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Oxylipin Pathway in Rice and Arabidopsis

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Journal of Integrative Plant Biology 2007年第1期49卷 43-51页

作者： e. Wassim Chehab john V. Perea Banu Gopalan Steve Theg Katayoon Dehesh Section of Plant Biology University of California-Davis Davis CA 95616 USA

Plants have evolved complex signaling pathways to coordinate responses to developmental and environmental Information. The oxylipin pathway Is one pivotal lipid-based signaling network, composed of several competing branch pathways, that determines the plant＇s ability to adapt to various stimuli. Activation of the oxyllpln pathway Induces the de novo synthesis of biologically active metabolltes called ＂oxyllplns＂. The relative levels of these metabolltes are a distinct indicator of each plant species and determine the ability of plants to adapt to different stimuli. The two major branches of the oxyllpln pathway, allene oxide synthase （AOS） and hydroperoxlde lyase （HPL） are responsible for production of the signaling compounds, jasmonates and aldehydes respectively. Here, we compare and contrast the regulation of AOS and HPL branch pathways In rice and Arabidopsis as model monocotyledonous and dicotyledonous systems. These analyses provide new Insights Into the evolution of JAs and aldehydes signaling pathways, and the complex network of processes responsible for stress adaptations In monocots and dicots.

关键词： aldehydes allene oxide synthase Arabidopsis hydroperoxide lyase jasmonates oxylipin pathway rice

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Low phase noise hybrid silicon mode-locked lasers

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Frontiers of Optoelectronics 2014年第3期7卷 265-276页

作者： Sudharsanan SRINIVASAN Michael DAVeNPORT Martijn J. R. HeCK john HUTCHINSON erik NORBeRG Gregory FISH john bowers Department of electrical and Computer engineering University of California Santa Barbara CA 93106 USA Department of engineering Aarhus University Aarhus Denmark Aurrion Inc. Goleta CA 93117 USA

In this paper, we review recent results on hybrid silicon mode-locked lasers with a focus on low phase noise optical pulse generation. Taking a high level design approach to lowering phase noise, we show the need for long on-chip optical delay lines for mode-locked lasers to reach and overcome material limits. Key results include demonstration of the longest （cavity length 9 cm） integrated on-chip mode locked laser, 14 dB reduction of Lorentzian noise on a 20 GHz radio-frequency （RF） signal, and greater than 55 dB optical supermode noise suppres- sion using harmonically mode locked long cavity laser, 10 GHz passively mode locked laser with 15 kHz linewidth using on-chip all optical feedback stabilization.

关键词： optoelectronic devices mode-locked lasers semiconductor lasers

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