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Frontiers of Chemical Science and Engineering 2014年第2期8卷 212-218页

作者： Anton alvarez-MAJMUTOV Jinwen CHEN Natural Resources Canada CanmetENERGY One Oil Patch Drive Devon AB T9G 1A8 Canada

This paper presents an evaluation of the energy intensity and related greenhouse gas/CO2 emissions of integrated oil sands crude upgrading processes. Two major oil sands crude upgrading schemes currently used in Canadian oil sands operations were investigated： cokingbased and hydroconversion-based. The analysis, which was based on a robust process model of the entire process, was constructed in Aspen HYSYS and calibrated with representative data. Simulations were conducted for the two upgrading schemes in order to generate a detailed inventory of the required energy and utility inputs： process fuel, steam, hydrogen and power. It was concluded that while hydroconversion-based scheme yields considerably higher amount of synthetic crude oil （SCO） than the cokerbased scheme （94 wt-% vs. 76 wt-%）, it consumes more energy and is therefore more CO2-intensive （413.2kg CO2/m3sco vs. 216.4kg CO2/m^3sco）. This substantial difference results from the large amount of hydrogen consumed in the ebullated-bed hydroconverter in the hydroconversion-based scheme, as hydrogen production through conventional methane steam reforming is highly energy-intensive and therefore the major source of CO2 emission. Further simulations indicated that optimization of hydroconverter operating variables had only a minor effect on the overall CO2 emission due to the complex trade-off effect between energy inputs.

关键词： Oil sands crude upgrading hydroconversion,process modeling greenhouse gas emissions

Predicting coastal morphological changes with empirical orthogonal function method

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Water Science and Engineering 2016年第1期9卷 14-20页

作者： fernando alvarez shun-qi pan Hydro-environmental Research Centre School of Engineering Cardiff University Cardiff CF24 3AA UK

In order to improve the accuracy of prediction when using the empirical orthogonal function （EOF） method, this paper describes a novel approach for two-dimensional （2D） EOF analysis based on extrapolating both the spatial and temporal EOF components for long-term prediction of coastal morphological changes. The approach was investigated with data obtained from a process-based numerical model, COAST2D, which was applied to an idealized study site with a group of shore-parallel breakwaters. The progressive behavior of the spatial and temporal EOF components, related to bathymetric changes over a training period, was demonstrated, and EOF components were extrapolated with combined linear and exponential functions for long-term prediction. The extrapolated EOF components were then used to reconstruct bathymetric changes. The comparison of the reconstructed bathymetric changes with the modeled results from the COAST2D model illustrates that the presented approach can be effective for long-term prediction of coastal morphological changes, and extrapolating both the spatial and temporal EOF components yields better results than extrapolating only the temporal EOF component.

关键词： EOF method Coastal morphological change Long-term prediction Process-based numerical model Shore-parallel breakwater

Pre-emergence herbicides affect seedling emergence of tropical forest tree species

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Journal of Forestry Research 2017年第4期28卷 733-739页

作者： Diego Cerveira de Souza vera Lex Engel Forest Science Department Agronomic Sciences College-FCASao Paulo State University – UNESPP.O. Box 237BotucatuSP 18603-970Brazil

Testing techniques to reduce weed infestation is a crucial step in developing direct tree seeding systems. The use of pre-emergence herbicides may be an alternative to manual weeding techniques, but so far, information on how they affect the seeds of native tree species is scarce. We established a greenhouse experiment to evaluate the effects of four pre-emergence herbicides (atrazine, diuron, isoxaflutole and oxyfluorfen) on weed suppression and seedling emergence and early growth of seven tropical forest tree species (Annona coriacea Mart., Citharexylum myrianthum Cham., Cordia ecalyculata Vell., Peltophorum dubium (Spreng.) Taub., Psidium guajava L., Pterogyne nitens Tul. and Schinus terebinthifolia Raddi). The experimental design was a randomized complete block design with five treatments and five replicates. The treatments consisted of a single dose of each pre-emergence herbicide and a control. Throughout the 60 days after sowing we evaluated weed cover and seedling emergence and early growth of tree species. Overall, our results suggest that all tested herbicides reduced weed cover; however, they also negatively affected tree species seedling emergence. Of the four herbicides tested, atrazine and diuron showed the greatest effects on tree seedling emergence, oxyfluorfen was least aggressive towards native species and isoxaflutole was most effective in weed control. Native tree species varied in their responses to herbicides, indicating that future experiments should increase the number of species tested as well as investigate how seed traits can affect the species responses to different herbicides.

关键词： Pre-emergence herbicides Weed control Direct seeding Seedling emergence Tropical seasonal forests

Cellular automata model for traffic flow with safe driving conditions

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Chinese Physics B 2014年第5期23卷 216-226页

作者： María Elena Lárraga Luis alvarez-Icaza Instituto de Ingeniería Universidad Nacional Autónoma de México04510Coyoacán D.F.México

In this paper, a recently introduced cellular automata （CA） model is used for a statistical analysis of the inner micro-scopic structure of synchronized traffic flow. The analysis focuses on the formation and dissolution of clusters or platoons of vehicles, as the mechanism that causes the presence of this synchronized traffic state with a high flow. This platoon formation is one of the most interesting phenomena observed in traffic flows and plays an important role both in manual and automated highway systems （AHS）. Simulation results, obtained from a single-lane system under periodic boundary conditions indicate that in the density region where the synchronized state is observed, most vehicles travel together in pla- toons with approximately the same speed and small spatial distances. The examination of velocity variations and individual vehicle gaps shows that the flow corresponding to the synchronized state is stable, safe and highly correlated. Moreover, results indicate that the observed platoon formation in real traffic is reproduced in simulations by the relation between vehicle headway and velocity that is embedded in the dynamics definition of the CA model.

关键词： traffic flow models synchronized traffic cellular automata platoons formation

Same or different?Abstract relational concept use in juvenile bamboo sharks and Malawi cichlids

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Current Zoology 2021年第3期67卷 279-292页

作者： Theodora Fuss Leonie John vera Schluessel Institute of Zoology Rheinische Friedrich-Wilhelms-University BonnMeckenheimer Allee 169Bonn53115Germany

Sorting objects and events into categories and concepts is an important cognitive prerequisite that spares an individual the learning of every object or situation encountered in its daily ***,specific items are classified in general groups that allow fast responses to novel *** present study assessed whether bamboo sharks Chiloscyllium griseum and Malawi cichlids Pseudotropheus zebra can distinguish sets of stimuli(each stimulus consisting of two abstract,geometric objects)that meet two conceptual preconditions,i.e.,(1)"sameness"versus"difference"and(2)a certain spatial arrangement of both *** two alternative forced choice experiments,individuals were first trained to choose two different,vertically arranged objects from two different but horizontally arranged *** discriminations were followed by extensive transfer test *** tests using stimuli consisting of(a)black and gray circles and(b)squares with novel geometric patterns provided conflicting information with respect to the learnt rule"choose two different,vertically arranged objects",thereby investigating(1)the individuals'ability to transfer previously gained knowledge to novel stimuli and(2)the abstract relational concept(s)or rule(s)applied to categorize these novel *** results suggest that the level of processing and usage of both abstract concepts differed considerably between bamboo sharks and Malawi *** sharks seemed to combine both concepts-although not with equal but hierarchical prominence-pointing to advanced cognitive ***,Malawi cichlids had difficulties in discriminating between symbols and failed to apply the acquired training knowledge on new sets of geometric and,in particular,gray-level transfer stimuli.

关键词： visual concept learning spatial arrangement relational abstract concept Malawi cichlid bamboo shark

The method of residual‑based bootstrap averaging of the forecast ensemble

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Financial Innovation 2023年第1期9卷 991-1002页

作者： vera Ivanyuk Department of Data Analysis and Machine Learning Financial University49 Leningradsky ProspektMoscowRussia 125993

This paper presents an optimization approach—residual-based bootstrap averaging(RBBA)—for different types of forecast *** traditional residual-mean-square-error-based ensemble forecast averaging approaches,the RBBA method attempts to find optimal forecast weights in an ensemble and allows for their combi-nation into the most effective additive *** the RBBA method,all the different types of forecasts obtain the optimal weights for ensemble residuals that are statisti-cally optimal in terms of the fitness function of the *** studies have been conducted to demonstrate why and how the RBBA method *** experi-mental results based on the real-world time series of contemporary stock exchanges show that the RBBA method can produce ensemble forecasts with good generalization ability.

关键词： Forecast ensembles Time series Artificial neural networks

Linking plant metabolism and immunity through methionine biosynthesis

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Molecular Plant 2022年第1期15卷 6-8页

作者： Francisco Escaray Amelia Felipo-Benavent Pablo vera Instituto de Biología Molecular y Celular de Plantas Universidad Politécnica de Valencia-C.S.I.CCiudad Politécnica de la InnovaciónEdificio 8EIngeniero Fausto Elios/n46022 ValenciaSpain

Plants respond to pathogenic cues with a transcriptional reprog-ramming that leads to de novo production of defense-related pro-teins and a huge variety of secondary metabolites(e.g.,phyto-alexins,phenolics,etc.).Activation of these host defenses,which contribute to halt the intruder as part of the resistance,im-plies an increased demand for metabolic energy and carbon skel-etons derived from primary metabolism(Bolton,2009).

关键词： metabolism immunity Bolton

Spontaneous and stimulated electron-photon interactions in nanoscale plasmonic near fields

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Light(Science & Applications) 2021年第5期10卷 867-880页

作者： Matthias Liebtrau Murat Sivis Armin Feisto Hugo Lourenco-Martins Nicolas Pazos-Pérez Ramon a.alvarez Puebla F.Javier Garcia de Abajo Albert Polman Claus Ropers Center for Nanophotonics AMOLF1098 XG AmsterdamThe Netherlands th Physical Institute-Solids and Nanostructures University of GÖttingen37077 GÖttingenGermany Max Plank Institute for Biophysical Chemistry 37077 GottingenGermany Department of Physical Chemistry and EMaS Universitat Rovira i Virgili43007 TarragonaSpain ICREA-Institucio Catalana de Recerca i Estudis Avangats 08010 BarcelonaSpain ICFO-Institut de Ciencies Fotoniques The Barcelona Institute of Science and Technology08860 Castelldefels(Barcelona)Spain

The interplay between free electrons,light,and matter offers unique prospects for space,time,and energy resolved optical material characterization,structured light generation,and quantum information ***,we study the nanoscale features of spontaneous and stimulated electron–photon interactions mediated by localized surface plasmon resonances at the tips of a gold nanostar using electron energy-loss spectroscopy(EELS),cathodoluminescence spectroscopy(CL),and photon-induced near-field electron microscopy(PINEM).Supported by numerical electromagnetic boundary-element method(BEM)calculations,we show that the different coupling mechanisms probed by EELS,CL,and PINEM feature the same spatial dependence on the electric field distribution of the tip ***,the electron–photon interaction strength is found to vary with the incident electron velocity,as determined by the spatial Fourier transform of the electric near-field component parallel to the electron *** the tightly confined plasmonic tip resonances,our calculations suggest an optimum coupling velocity at electron energies as low as a few *** results are discussed in the context of more complex geometries supporting multiple modes with spatial and spectral *** provide fundamental insights into spontaneous and stimulated electron-light-matter interactions with key implications for research on(quantum)coherent optical phenomena at the nanoscale.

关键词： photon quantum coupling

IAS/IFRS and financial reporting quality:Lessons from the European experience

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China Journal of Accounting Research 2013年第4期6卷 247-263页

作者： vera Palea Department of Economics and Statistics "Cognetti de Martiis" University of Torino

This paper discusses the effects of the adoption of IAS/IFRS in Europe on the quality of financial *** doing so,it adopts the perspective of stock market investors and focuses on value-relevance *** adoption of IAS/IFRS in Europe is an example of accounting standardization among countries with different institutional frameworks and enforcement *** allows investigating whether,and to what extent,accounting regulation per se can affect the quality of financial reporting and leads to convergence in financial *** is a key issue for standard setting purposes as IAS/IFRS have been adopted in very diverse countries all over the world,and many others are likely to adopt them in the near future.

关键词： Financial reporting quality IAS/IFRS Value-relevance European Regulation 1606/2002

Role of Osteoprotegerin and Receptor Activator of Nuclear Factor-kB Ligand in Bone Loss Related to Advanced Chronic Obstructive Pulmonary Disease

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Chinese Medical Journal 2016年第14期129卷 1696-1703页

作者： Ludmila Ugay Evgenia Kochetkova vera Nevzorova Yuliya Maistrovskaia Departement of Pulmonology Central Scientific Research Laboratory Pacific State Medical University Vladivostok 690950 Russian Federation

Background： Osteoporosis is a common complication of chronic obstructive pulmonary disease （COPD）. Recent clinical and biological researches have increasingly delineated the biomolecular pathways of bone metabolism regulation in COPD. We extended this work by examining the specific association and potential contribution of the osteoprotegerin （OPG）/receptor activator of nuclear factor-riB ligand （RANKL） axis to the pathogenesis of osteoporosis in advanced COPD. The aim of this study was to assess the relationships of serum OPG, RANKL, and tumor necrosis factor-alpha （TNF-a） with bone turnover in men with very severe COPD. Methods： Pulmonary function, T-score at the lumbar spine （LS） and femoral neck （FN）, serum OPG, RANKL, soluble receptor of tumor necrosis factor-alpha-1 and 11 （sTNFR-I, sTNFR-II）, osteocalcin （OC）, and β-CrossLaps （βCL） levels were measured in 45 men with very severe stage COPD and 36 male non-COPD volunteers. COPD patients and healthy controls were compared using all independent t-test and Mann-Whitney U-test. The Pearson coefficient was used to assess the relationships between variables. Results： OPG and OC were lower in male COPD patients than in control subjects whereas RANKL, serum ~CL, TN F-o~, and its receptors were higher. OPG directly correlated with forced expiratory volume in I s （FEVI） % predicted （r = 0.46, P 〈 0.005）, OC （r= 0.34, P 〈 0.05）, LS （I.= 0.56, P 〈 0.001 ）, and FN T-score （r= 0.47, P 〈 0.01 ）. In contrast, serum RANKL inversely associated with LS and FN T-score （r = -0.62, P 〈 0.001 and r = -0.48, P 〈 0.001 ） but directly correlated with [3CL （r = 0.48, P 〈 0.001 ）. In addition, OPG was inversely correlated with RANKL （r = -0.39, P 〈 0.01 ）, TNF-a （r = -0.56, P 〈 0.001 ）, and sTNFR-I （r = -0.40, P 〈 0.01 ）. Conelusion： Our results suggest that serum OPG and RANKL levels are inversely associated with bone loss in men with advanced stage COPD.

关键词： Chronic Obstructive Puhnonary Disease Osteoporosis Osteoprotegerin Receptor Activator of Nuclear Factor-KBLigand Tumor Necrosis Factor Receptors: Tumor Necrosis Factor-alpha