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疯狂英语（新读写） 2024年第1期 1-1页

作者： Wallace stevens 佚名(译) 不详

人要有冬的心灵才懂得看白霜以及松林的枝干上包裹的雪;要被冷冻很长时间才能目睹刺柏上冰晶蓬乱,云杉勾勒着远远闪烁的.

关键词：刺柏白霜冰晶

The function of animal ‘eyespots’:Conspicuousness but not eye mimicry is k.y

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Current Zoology 2009年第5期55卷 319-326页

作者： Martin stevens Abi CANTOR Julia GRAHAM Isabel S.WINNEY Department of Zoology University of CambridgeDowning Street

Many animals are mark.d with conspicuous circular features often called ＇eyespots＇, which intimidate predators, preventing or halting an attack. It has long been assumed that eyespots work.by mimick.ng the eyes of larger animals, but recent experiments have indicated that conspicuousness and contrast is important in eyespot function, and not eye mimicry. We undertak. two further experiments to distinguish between the conspicuousness and mimicry hypotheses, by using artificial prey presented to wild avian predators in the field. In experiment 1, we test if eyespot effectiveness depends on the mark.ng shape （bar or circle） and arrangement （eye-lik. and non-eye-lik. positions）. We find no difference between shapes or arrangement; all spots were equally effective in scaring birds. In experiment 2, we test if the often yellow and black.colors of eyespots mimic the eyes of birds of prey. We find no effect of shape, and no advantage to yellow and black.spots over non-eye-lik. but equally conspicuous colors. The consistent finding is that eyespot function lies in being a conspicuous signal to predators, and not necessarily due to eye mimicry [ Current Zoology 55 （5）： 319 - 326, 2009].

关键词： Eyespots Conspicuousness Mimicry Predation Protective coloration

Review of solvent based carbon-dioxide capture technologies

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Frontiers of Chemical Science and Engineering 2015年第2期9卷 125-141页

作者： k.thryn A. MUMFORD Yue WU k.thryn H. SMITH Geoffrey W. stevens Peter Cook.Centre for CCS Research Particulate Fluids Processing Centre Cooperative Centre for Greenhouse Gas Technologies Department of Chemical and Biomolecular Engineering The University of Melbourne Victoria Australia

Currently, a large proportion of global fossil fuel emissions originate from large point sources such as power generation or industrial processes. This trend is expected to continue until the year 2030 and beyond. Carbon capture and storage （CCS）, a straightforward and effective carbon reduction approach, will play a significant role in reducing emissions from these sources into the future if atmospheric carbon dioxide （CO2） emissions are to be stabilized and global warming limited below a threshold of 2 ℃. This review provides an update on the status of large scale integrated CCS technologies using solvent absorption for CO2 capture and provides an insight into the development of new solvents, including advanced amine solvents, amino acid salts, carbonate systems, aqueous ammonia, immiscible liquids and ionic liquids. These proposed new solvents aim to reduce the overall cost CO2 capture by improving the CO2 absorption rate, CO2 capture capacity, thereby reducing equipment size and decreasing the energy required for solvent regeneration.

关键词： carbon dioxide carbon capture solventabsorption large scale

Modelling of a post-combustion carbon dioxide capture absorber using potassium carbonate solvent in Aspen Custom Modeller

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Chinese Journal of Chemical Engineering 2018年第11期26卷 2327-2336页

作者： Yue Wu Fan Wu Guoping Hu Nouman R.Mirza Geoffrey W.stevens k.thryn A.Mumford Department of Chemical and Biomolecular Engineering The University of Melbourne Peter Cook.Centre for CCS Research The University of Melbourne Particulate Fluids Processing Centre (PFPC) The University of Melbourne

The process models for an equilibrium CO_2 absorber and a rate based CO_2 absorber using potassium carbonate(k. CO3) solvents were developed in Aspen Custom Modeller(ACM) to remove CO_2 from a flue gas. The process model utilised the Electrolyte Non-Random Two Liquid(ENRTL) thermodynamic model and various pack.ng correlations. The results from the ACM equilibrium model shows good agreement with an inbuilt Aspen Plus?model when using the same input conditions. By further introducing a Murphree efficiency which is related to mass transfer and pack.ng hydraulics, the equilibrium model can validate the experimental results from a pilot plant within a deviation of 10%. A more rigorous rate based model included mass and energy flux across the interface and the enhancement effect resulting from chemical reactions. The rate based model was validated using experimental data from pilot plants and was shown to predict the results to within 10%. A parametric sensitivity analysis showed that inlet flue gas flowrate and k. CO3 concentration in the lean solvent has significant impact on CO_2 recovery. Although both models can provide reasonable predictions based on pilot plant results, the rate based model is more advanced as it can explain mass and heat transfer, transport phenomena and chemical reactions occurring inside the absorber without introducing an empirical Murphree efficiency.

关键词： Equilibrium Rate based Modelling Absorber Potassium carbonate

Microbial community structure across grazing treatments and environmental gradients in the Serengeti

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Soil Ecology Letters 2022年第1期4卷 45-56页

作者： Bo Maxwell stevens Derek.Lee Sonderegger Nancy Collins Johnson School of Earth and Sustainability Northern Arizona UniversityFlagstaffAZ 86011USA Department of Mathematics and Statistics Northern Arizona UniversityFlagstaffAZ 86001USA Department of Biological Sciences Northern Arizona UniversityFlagstaffAZ 86011USA

As one of the last remaining naturally grazed ecosystems on Earth,the Serengeti National Park.is an ideal location to study the influence of migratory mammals on the structure of microbial communities and the factors that generate biogeography of soil ***,volcanic inputs generate environmental gradients that may also structure microbial *** studied 16S rRNA amplicons in a 13-year herbivore removal experiment to examine the influence of grazing and environmental gradients on the natural distribution of soil *** of mammalian herbivores shifted microbial community structure,with 31 taxa that were significant indicator taxa of the ungrazed treatment and three taxa that were indicators of the grazed *** abundance of many taxa were correlated with soil texture,phosphorus,iron,calcium and rainfall,and the evenness of taxa within samples was also correlated with these *** general linear mixed effects models with single predictors of multiple,highly correlated variables of beta diversity were consistent with a significant,but weak.2%),effect of grazing,and stronger effects of phosphorus(14%).Beta diversity of microbial communities was greater in grazed than in ungrazed plots;suggesting that the impacts of grazing on community assembly of microbes results from deterministic environmental filtering caused by the influence of herbivores on plant communities and soil properties rather than stochastic dispersal via herds of large *** herbivore effects are superimposed on deterministic environmental filtering by natural soil and precipitation gradients across the Serengeti.

关键词： Soil bacteria Community ecology Grazing Serengeti National Park Soil texture Phosphorus

Endoscopic ultrasound for the diagnosis of chronic pancreatitis

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World Journal of Gastroenterology 2010年第23期16卷 2841-2850页

作者： Tyler stevens Mansour A Parsi Digestive Disease Institute Cleveland Clinic Foundation

Endoscopic ultrasound(EUS) has become a well accepted test for the diagnosis of chronic *** include its ability to detect subtle and severe changes of the pancreatic duct and parenchyma,and its relative safety compared with endoscopic retrograde *** include inter-and intraobserver variability,operator dependence,and an incomplete understanding of its true *** Rosemont classif ication has recently been proposed as a weighted,standardized method that may improve EUS chronic pancreatitis *** paper reviews the published evidence regarding the accuracy of EUS in chronic pancreatitis diagnosis,and enumerates the emerging technologies that have been recently studied which may ultimately improve endosonographic imaging of the pancreas.

关键词： Chronic pancreatitis Contrast-enhanced endoscopic ultrasound Diagnosis Digital image analysis Elastography Endoscopic ultrasound Pancreatic function testing Rosemont classification

Individual variation in ballooning dispersal by black.widow spiderlings： The effects of family and social rearing

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Current Zoology 2015年第3期61卷 520-528页

作者： J. Chadwick.JOHNSON Rebecca HALPIN Dale stevens II Annik. VANNAN Jesse LAM k.tie BRATSCH School of Mathematical and Natural Sciences (2352) Arizona State University at the West Campus Glendale AZ 85306 USA

Individual behavioral variation is ubiquitous across taxa and important to understand if we wish to fully use beha- vioral data to understand the ecology and evolution of organisms. Only recently have studies of individual variation in dispersal behavior become a focus of research. A better understanding of individual variation in dispersal behavior is lik.ly to improve our understanding of population dynamics. In particular, the dynamics of critically small populations （endangered species） and large populations （pest species） may be driven by unique dispersal variants. Here we documented individual variation in the ballooning dispersal behavior of Western black.widow spiderlings Latrodectus hesperus, an urban pest species found in superabundant in- festations throughout cities of the desert Southwest USA. We found a great deal of family-level variation in ballooning dispersal, and this variation was highly consistent （repeatable） across time. Maternal egg investment was a poor predictor of this ballooning dispersal. Instead, we show that spiderlings reared in isolation are significantly slower to disperse than spiderlings raised in a more natural setting surrounded by full siblings. Thus, our study examines a widespread but poorly understood dispersal behavior （ballooning）, and suggests urban pest population dynamics are lik.ly driven by the interaction of variation in individuals, families and social environments

关键词： Individual variation Dispersal Spiders Ballooning Social rearing

Ovarian autoimmune disease： clinical concepts and anima models

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Cellular & Molecular Immunology 2014年第6期11卷 510-521页

作者： Bryce D Warren William k.k.nsey Lynda k.McGinnis Lane k.Christenson Susmita Jasti Anne M stevens Brian k.Petroff Margaret G Petroff Department of Anatomy and Cell Biology University of Kansas Medical Center Kansas City KS USA Department of Molecular and Integrative Physiology University of Kansas Medical Center Kansas City KS USA Research Center for Immunity and I mmunotherapies Children's Hospital and Regional Medical Center and Division of Rheumatology Department of Pediatrics University of Washington Seattle WA USA Department of Internal Medicine University of Kansas Medical Center Kansas City KS USA Present address: Department of Pathobiology and Diagnostic Investigation Michigan State University College of Veterinary Medicine East Lansing MI USA

The ovary is not an immunologically privileged organ, but a break.own in tolerogenic mechanisms for ovary-specific antigens has disastrous consequences on fertility in women, and this is replicated in murine models of autoimmune disease. Isolated ovarian autoimmune disease is rare in women, lik.ly due to the severity of the disease and the inability to transmit genetic information conferring the ovarian disease across generations. Nonetheless, autoimmune oophoritis is often observed in association with other autoimmune diseases, particularly autoimmune adrenal disease, and tak.s a toll on both society and individual health. Studies in mice have revealed at least two mechanisms that protect the ovary from autoimmune attack. These mechanisms include control of autoreactive T cells by thymus-derived regulatory T cells, as well as a role for the autoimmune regulator （AIRE）, a transcriptional regulator that induces expression of tissue-restricted antigens in medullary thymic epithelial cells during development of T cells. Although the latter mechanism is incompletely defined, it is well established that failure of either results in autoimmune-mediated targeting and depletion of ovarian follicles. In this review, we will address the clinical features and consequences of autoimmune-mediated ovarian infertility in women, as well as the possible mechanisms of disease as revealed by animal models.

关键词：不育家庭特征卵巢卵巢炎模型动物生育力胸腺胰岛素小鼠

Prediction of dispersed phase holdup in pulsed disc and doughnut solvent extraction columns under different mass transfer conditions

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Chinese Journal of Chemical Engineering 2016年第2期24卷 226-231页

作者： Yong Wang k.thryn H.Smith k.thryn Mumford Teobaldo F.Grabin Zheng Li Geoffrey W.stevens Particulate Fluids Processing Centre Department of Chemical and Biomolecular EngineeringThe University of Melbourne

Using experimental data from a number of pulsed disc and doughnut solvent extraction columns, a unified correla- tion for the prediction of dispersed phase holdup that considers the effects of mass transfer is presented. Pulsed disc and doughnut solvent extraction columns （PDDC） have been used for a range of important applications such as ura- nium extraction and nuclear fuel recycling. Although the dispersed phase holdup in a PDDC has been presented by some researchers, there is still the need to develop a robust correlation that can predict the experimental dispersed phase holdup over a range of operating conditions including the effects of mass transfer direction. In this study, dis- persed phase holdup data from different literature sources for a PDDC were used to refit constants for the correlation presented by k.mar and Hartland lind. Eng. Chem. Res.,27 （1988）,131-138] which did not consider the effect of col- umn geometry. In order to incorporate the characteristic length of the PDDC （i.e. the plate spacing）, the unified cor- relation for holdup proposed by k.mar and Hartland based on data from eight different types of columns [Ind. Eng. Chem. Res.,34 （1995） 3925-3940] was refitted to the PDDC data. New constants have been presented for each hold- up correlation for a PDDC based on regression analysis using published holdup data from PDDCs that cover a range of onerating conditions and nhwical nronerties and consider the direction of mass transfer.

关键词： Solvent extraction Liquid extraction Pulsed disc and doughnut columns Solvent extraction column design Holdup Dispersed phase holdup Hydrodynamics of extraction columns

Recent advances in carbon dioxide capture and utilization with amines and ionic liquids

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Green Chemical Engineering 2020年第1期1卷 16-32页

作者： Yuxin Wu Jianhong Xu k.thryn Mumford Geoffrey W.stevens Weiyang Fei Yundong Wang The State k.y Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing100084China Department of Chemical Engineering The University of MelbourneParkvilleVictoria3010Australia

Global warming and climate change due to anthropogenic carbon dioxide(CO_(2))have aroused significant concerns at the global scale due to rapid economic growth in industries and other ***,CO_(2)capture,use,and storage have become particularly *** this review,general back.round and methods for CO_(2)capture and separation,in particular,on ionic liquids(ILs)-based solvents and materials,are *** surveys of ILs for CO_(2)absorption are presented,which focused mainly on experimental researches,and then the concept is extended to functionalized absorbents and recent developments for CO_(2)*** advantages and disadvantages of amines-based and ILs-based absorbents are discussed in this *** of traditional amines(MEA,MDEA,DEA,AMP,PZ,etc.)and ILs(conventional ILs,functionalized ILs,etc.)are ***,research progresses on CO_(2)separation are also introduced focusing mainly on amines and ILs-based membranes(*** amines membranes,SILMs).Futhermore,the fixation of CO_(2)into cyclic carbonates catalyzed by ILs(pure ILs,complex catalyst system with ILs,supported ILs,etc.)is summarized,clearly explaining the mechanism of CO_(2)fixation with ***,exploration of some recent studies about CO_(2)capture and conversion by ILs and challenges for further progress are presented and related suggestions are put forward.

关键词： Carbon dioxide Capture Separation Amines Ionic liquids Cycloaddition