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Drought can offset potential water use efficiency of forest ecosystems from rising atmospheric CO2

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journal of Environmental Sciences 2020年第4期32卷 262-274页

作者： Ning Liu jatin Kala Shirong Liu Vanessa Haverd Bernard Dell Keith R.j.Smettem Richard j.harper Environmental and Conservation Sciences Murdoch UniversityMurdochWA 6150 Australia Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing 10091 China CSIRO Oceans&Atmosphere ACT 2600 Australia

Increasing atmospheric CO2 is both leading to climate change and providing a potential fertilisation effect on plant ***,southern Australia has also experienced a significant decline in rainfall over the last 30 years,resulting in increased vegetative water *** better understand the dynamics and responses of Australian forest ecosystems to drought and elevated CO2,the magnitude and trend in water use efficiency(WUE)of forests,and their response to drought and elevated CO2 from 1982 to 2014 were analysed,using the best available model estimates constrained by observed fluxes from simulations with fixed and time-varying *** ratio of gross primary productivity(GPP)to evapotranspiration(ET)(WUEe)was used to identify the ecosystem scale WUE,while the ratio of GPP to transpiration(Tr)(WUEc)was used as a measure of canopy scale *** increased significantly in northern Australia(p<0.001)for woody savannas(WSA),whereas there was a slight decline in the WUE of evergreen broadleaf forests(EBF)in the southeast and southwest of *** lag of WUEc to drought was consistent and relatively short and stable between biomes(<3 months),but notably varied for WUEe,with a long time-lag(mean of 10 months).The dissimilar responses of WUEe and WUEc to climate change for different geographical areas result from the different proportion of Tr in ***2 fertilization and a wetter climate enhanced WUE in northern Australia,whereas drought offset the CO2 fertilization effect in southern Australia.

关键词： Water use efficiency Elevated CO2 Carbon sequestration,drought Forest Australia

Ecological factors influencing the beneficial endosymbionts of the hemlock woolly adelgid (Hemiptera:Adelgidae)

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Insect Science 2019年第1期26卷 97-107页

作者： Angela M.Mech Sherilyn j.harper Nathan P.Havill Carol D.von Dohlen Gaelen R.Burke Department of Entomology University of GeorgiaAthensGeorgiaUSA School of Environmental and Forest Sciences University of WashingtonSeattleWashingtonUSA USDA Forest Service Northern Research StationHamdenConnecticutUSA Department of Biology Utah State UniversityLoganUtahUSA

Bacterial endosymbionts of sap-sucking insects provide their host with a num- ber of beneficial qualities,including the supply of nutrition,defense against parasitoids, and protection from heat *** to these bacterial associates can therefore have a negative impact on the fitness of their insect *** evaluated observational and experi- mental factors regarding the normative hemlock woolly adelgid (Adelges tsugae Annand) (Hemiptera:Adelgidae)to help understand the roles of its three recently identified symbionts,including under heat stress *** prevalence of ***'s facultafive symbiont (Serratia symbiotica)was examined at different spatial scales to determine how variable infection rates are for this *** was no significant difference found in infection rates between adelgids on a tree,within a plot,or within a ***, significantly more adelgids in Georgia (95%)had *** compared to those in New York (68%).Microsatellite genotyping of the adelgids found that this difference was most likely not the result of a second introduction *** into eastern North *** *** proportions between first and fourth instars showed that symbiont absence did not affect the ability *** to survive *** of sym- biont densities within each adelgid found that when *** was absent,the density of obligate symbionts was significantly *** to heat stress (32.5℃)was not consistently correlated with changes in symbiont densities over a 4-d ***,we have shown that symbiont prevalence and densities vary within the broad population of *** in eastern North America,with potentially significant effects upon the ecology of this important pest.

关键词： Adelges tsugae Anncindia adelgestsuga bacterial endosymbionts Serratia symbiotica Pseudomonas adelgestsugas

Toward optical coherence tomography on a chip: in vivo three-dimensional human retinal imaging using photonic integrated circuit-based arrayed waveguide gratings

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Light(Science & Applications) 2021年第1期10卷 71-85页

作者： Elisabet A.Rank Ryan Sentosa Danielle j.harper Matthias Salas Anna Gaugutz Dana Seyringer Stefan Nevlacsil Alejandro Maese-Novo Moritz Eggeling Paul Muellner Rainer Hainberger Martin Sagmeister jochen Kraft Rainer ALeitgeb Wolfgang Drexler Center for Medical Physics and Biomedical Engineering Medical University of ViennaWaehringer Guertel 18-20/4 L1090 ViennaAustria Research Centre for Microtechnology Vorarlberg University of Applied SciencesHochschulstrasse 16850 DornbirnAustria AIT Austrian Institute of Technology GmbH Gieffinggasse 41210 ViennaAustria ams AG Tobelbader Strasse 308141 PremstaettenAustria

In this work,we present a significant step toward in vivo ophthalmic optical coherence tomography and angiography on a photonic integrated *** diffraction gratings used in spectral-domain optical coherence tomography can be replaced by photonic integrated circuits comprising an arrayed waveguide *** arrayed waveguide grating designs with 256 channels were tested,which enabled the first chip-based optical coherence tomography and angiography in vivo three-dimensional human retinal *** 1 supports a bandwidth of 22nm,with which a sensitivity of up to 91 dB(830μW) and an axial resolution of 10.7 pm was *** 2 supports a bandwidth of 48 nm,with which a sensitivity of 90 dB(480μW) and an axial resolution of 6.5μm was *** silicon nitride-based integrated optical waveguides were fabricated with a fully CMOS-compatible process,which allows their monolithic co-integration on top of an optoelectronic silicon *** a benchmark for chip-based optical coherence tomography,tomograms generated by a commercially available clinical spectral-domain optical coherence tomography system were compared to those acquired with on-chip *** similarities in the tomograms demonstrate the significant clinical potential for further integration of optical coherence tomography on a chip system.

关键词： waveguide arrayed optical

An overview of PCI in the very elderly

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journal of Geriatric Cardiology 2015年第2期12卷 174-184页

作者： Vimalraj Bogana Shanmugam Richard harper Ian Meredith Yuvaraj Malaiapan Peter j Psaltis Cardiovascular Research Centre Monash University 246 Clayton Road Clayton Victoria 3168 Australia

Cardiovascular disease, and in particular ischemic heart disease （IHD）, is a major cause of morbidity and mortality in the very elderly （〉 80 years） worldwide. These patients represent a rapidly growing cohort presenting for percntaneous coronary intervention （PCI）, now constituting more than one in five patients treated with PCI in real-world practice. Furthermore, they often have greater ischemic burden than their younger counterparts, suggesting that they have greater scope of benefit from coronary revascularization therapy. Despite this, the very elderly are frequently under-represented in clinical revascularization trials and historically there has been a degree of physician reluctance in referring them for PCI procedures, with perceptions of disappointing outcomes, low success and high complication rates. Several issues have contributed to this, including the tendency for older patients with IHD to present late, with atypical symptoms or non-diagnostic ECGs, and reservations regarding their procedural risk-to-benefit ratio, due to shorter life expectancy, presence of comorbidities and increased bleeding risk from antiplatelet and anticoagulation medications. However, advances in PCI technology and techniques over the past decade have led to better outcomes and lower risk of complications and the existing body of evidence now indicates that the very elderly actually derive more relative benefit from PCI than younger populations. Importantly, this applies to all PCI settings： elective, urgent and emergency. This review discusses the role of PCI in the very elderly presenting with chronic stable IHD, non ST-elevation acute coronary syndrome, and ST-elevation myocardial infarction. It also addresses the clinical challenges met when considering PCI in this cohort and the ongoing need for research and development to further improve outcomes in these challenging patients.

关键词： Acute coronary syndrome Angina Antithrombotic therapy Myocardial infarction Octogenarians Percutaneous coronary intervention The elderly

Necrotic enteritis and antibiotic-free production of broiler chickens:Challenges in testing and using alternative products

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Animal Nutrition 2024年第1期16卷 288-298页

作者： robert j.Moore School of Science RMIT UniversityBundooraVictoria 3083Australia

The global trend towards raising broiler chickens without the use of in-feed antibiotics(IFAs)means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously *** supported the productivity performance of chickens and played a key role in maintaining their *** enteritis(NE)is an important disease of broilers that affects health,productivity,and welfare,and was previously well controlled by ***,with the reduction in IFA use,NE is resurgent in some *** and various feed additives,including pre-,pro-,and postbiotics,phytobiotics,fatty acids,and phage therapies have been introduced as alternative methods of NE *** some of these feed additives have specific activity against the NE pathogen,Clostridium perfringens,most have the more general goal of reinforcing gut *** reviews of the effects of many of these feed additives on gut health have been published ***,rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative NE treatments and translating laboratory research to real world commercial production *** review is based on the author's particular experience,reading,thoughts,and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these *** is put forward to stimulate thinking and discussion on the issues covered.

关键词： Necrotic enteritis Clostridium perfringens Vaccines Feed additive Farm management

The Orosirian(1800–2050 Ma)plate tectonic episode:Key for reconstructing the Proterozoic tectonic record

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Geoscience Frontiers 2023年第3期14卷 1-9页

作者： robert j.Stern Geosciences Dept. U Texas at DallasRichardsonTX 75083-0688United States

Eight lines of evidence indicate that the Orosirian Period in mid-Paleoproterozoic time was characterized by plate tectonics:ophiolites,low T/P metamorphism including eclogites,passive margin formation,tall mountains,paleomagnetic constraints,ore deposits,abundant S-type granites,and seismic images of paleo-subduction *** plate tectonic episode occurred about 1 billion years earlier than the present plate tectonic episode began in Neoproterozoic *** two plate tectonic episodes bracket the‘Boring Billion’,which may have been a protracted single lid tectonic episode that began when the supercontinent Nuna or Columbia *** of multiple lines of evidence for Orosirian plate tectonics demonstrates that Earth’s tectonic style can be reconstructed with some confidence back to at least Early Paleoproterozoic time,and thus the absence of compelling evidence for Mesoproterozoic plate tectonics is not obvious due to poor preservation.A tectono-magmatic lull2.3 Ga suggests an earlier episode of single lid *** for two episodes of plate tectonics and two episodes of single lid tectonics indicates that Earth switched between single lid and plate tectonics multiple times during the last 2.4 Ga.

关键词： Plate tectonics Single lid tectonics Urey ratio Paleoproterozoic