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Journal of Plant Ecology 2014年第6期7卷 535-543页

作者： gabriel Danyagri Qing-Lai Dang Faculty of Natural Resources Management Lakehead UniversityThunder BayOntario P7B 65E1Canada

Aims Some shade-tolerant understory tree species such as mountain maple(Acer spicatum L.)exhibit light-foraging growth *** in environmental conditions,such as the rise of carbon dioxide concentration([CO_(2)])in the atmosphere and soil warming,may affect the performance of these species under different light *** investigated how elevated[CO_(2)]and soil warm-ing influence the growth and biomass responses of mountain maple seedlings to light *** The treatments were two levels of light(100%and 30%of the ambient light in the greenhouse),two[CO_(2)](392μmol mol^(−1)(ambient)and 784μmol mol^(−1)(elevated))and two soil tempera-tures(Tsoil)(17 and 22℃).After one growing season,we measured seedling height,root collar diameter,leaf biomass,stem biomass and root *** findings We found that under the ambient[CO_(2)],the high-light level increased seedlings height by 70%and 56%at the low Tsoil and high Tsoil,*** the elevated[CO_(2)],however,the high-light level increased seedling height by 52%and 13%at the low Tsoil and high Tsoil,*** responses of biomasses to light generally followed the response patterns of height growth under both[CO_(2)]and Tsoil and the magnitude of biomass response to light was the lowest under the elevated[CO_(2)]and warmer *** results suggest that the elevated[CO_(2)]and warmer Tsoil under the projected future climate may have negative impact on the colonization of open sites and forest canopy gaps by mountain maple.

关键词： mountain maple elevated CO_(2) soil warming light availability height biomass

The Meaning of ＂Existence＂ and the Contingency of Sense

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Frontiers of Philosophy in China 2014年第1期9卷 109-129页

作者： Markus gabriel Intemational Centre for Philosophy University of Bonn D53012 Bonn Germany

In this paper I argue first for a revisionary ontology, that is, for an understanding of ＂existence＂ as the property of a field not to be empty. In this context, I distinguish between ＂metaphysics＂（the theory of totality or of fundamental reality） and ＂ontology＂（the systematic investigation into the meaning of ＂existence＂）. In the second part, I provide a sketch for a corresponding revisionary theory of the modalities in light of the new ontology proposed.

关键词： ontology world metaphysics modalities contingency necessity,sense

Combination of hydrotreating and delayed coking technologies for conversion of residue

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Chinese Journal of Chemical Engineering 2023年第11期63卷 209-219页

作者： José A.D.Munoz gabriel Páez Jorge Ancheyta Instituto Mexicano del Petróleo Eje Central Lázaro Cárdenas Norte 152Col.San Bartolo AtepehuacanMéxico City 07730México

Residue conversion by combining catalytic hydrotreating and delayed coking has been evaluated comparatively with both processes *** operating conditions are defined to achieve the greatest economic benefit for upgrading an atmospheric residue from a heavy crude oil.A literature model was adapted to simulate the hydrotreating reactor,and for delayed coking,correlations reported in the literature were *** results with both approaches were employed to calculate the techno-economic feasibility of the combined process *** combination of hydrotreating and delayed coking presented an increase in light fractions of 29% and a reduction in coke production of 47.8%.Based on the calculated net benefit values,it was demonstrated that the combination of hydrotreating and delayed coking is technically and economically better than using each process alone,with highest benefit of 57.7 USD·m^(-3).

关键词： Economic benefit Heavy oil Hydrotreating Delayed coking

Theoretical knowledge and psychomotor skill acquisition of basic life support training programme among secondary school students

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World Journal of Emergency Medicine 2019年第2期10卷 81-87页

作者： Israel Olatunji gabriel Joel O.Aluko School of Post Basic Nursing Programmes (Anaesthesia) Ahmadu Bello University Teaching Hospital The Department of Nursing University of Ilorin

BACKGROUND: The aim of the study is to evaluate the theoretical knowledge and psychomotor skill acquisition of basic life support(BLS) by a group of secondary school students in Nigeria pre and post BLS training. METHODS: This was quasi-experimental study design with 210 participants. They were taught on adult BLS and all the participants practiced BLS on a Resusci-Anne manikin immediately after the training. Data were collected using American Heart Association(AHA) structured questionnaire and psychomotor skills checklist for BLS at baseline, and post BLS ***: The pre-training knowledge score was 1.9±1.4. This increased after the BLS training to 11.4±2.4, and the mean difference between the pre and post BLS training scores was 9.48571. Pre-training psychomotor skill score was 0.00±0.00, this increased to 8.9±1.9 after the training, and the mean difference was 8.90000. The knowledge and psychomotor skill difference between pre and post BLS training was signifi cant(P<0.000).CONCLUSION: Most Nigerian secondary school students were not knowledgeable about BLS. Therefore, there is need for the creation of more awareness among the students.

关键词： Cardiopulmonary resuscitation Basic life support Education School students Lifesaving skills Nigeria

A Time-Dependent Wavepacket Method for Photodissociation Dynamics of Triatomic Molecule

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Chinese Physics Letters 2009年第7期26卷 111-114页

作者： Mohammad Noh Daud gabriel G. Balint-Kurti Department of Chemistry University of Malaya Kuala Lumpur 50603 Malaysia School of Chemistry University of Bristol Bristol BS8 1TS UK

We report a time-dependent quantum wavepacket theory employed to interpret the photoabsorption spectrum of the N20 molecule in terms of the nuclear motion on the upper 21A＇ and 11A＂ potential energy surfaces. The N2-O bond breaks upon excitation leading to dissociation. The total angular momentum is treated correctly taking into account the vector property of the electric field of the exciting radiation.

关键词： Atomic and molecular physics

Paludification reduces black spruce growth rate but does not alter tree water use efficiency in Canadian boreal forested peatlands

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Forest Ecosystems 2021年第2期8卷 373-386页

作者： Joannie Beaulne Étienne Boucher Michelle Garneau gabriel Magnan Geotop Research Center Université du Québec à MontréalMontréalQuébec H3C 3P8Canada Department of Geography Université du Québec à MontréalMontréalQuébec H3C 3P8Canada GRIL-UQAM Université du Québec à MontréalQuébec H3C 3P8Canada Centre d'études nordiques Université LavalMontréalQuébec G1V 0A6Canada

Background:Black spruce(Picea mariana(Mill.)BSP)-forested peatlands are widespread ecosystems in boreal North America in which peat accumulation,known as the paludification process,has been shown to induce forest growth *** continuously evolving environmental conditions(e.g.,water table rise,increasing peat thickness)in paludified forests may require tree growth mechanism adjustments over *** this study,we investigate tree ecophysiological mechanisms along a paludification gradient in a boreal forested peatland of eastern Canada by combining peat-based and tree-ring *** and oxygen stable isotopes in tree rings are used to document changes in carbon assimilation rates,stomatal conductance,and water use *** addition,paleohydrological analyses are performed to evaluate the dynamical ecophysiological adjustments of black spruce trees to site-specific water table ***:Increasing peat accumulation considerably impacts forest growth,but no significant differences in tree water use efficiency(iWUE)are found between the study ***-ring isotopic analysis indicates no iWUE decrease over the last 100 years,but rather an important increase at each site up to the 1980 s,before iWUE ***,inferred basal area increments do not reflect such ***,iWUE variations do not reflect tree ecophysiological adjustments required by changes in growing *** water table variations induce no changes in ecophysiological mechanisms,but a synchronous shift in iWUE is observed at all sites in the mid-1980 ***:Our study shows that paludification induces black spruce growth decline without altering tree water use efficiency in boreal forested *** findings highlight that failing to account for paludification-related carbon use and allocation could result in the overestimation of aboveground biomass production in paludified *** research on carbon allocation strategies is of utmos

关键词： Black spruce growth Boreal biome Carbon allocation Ecophysiological mechanisms Forested peatland Paludification Stable isotope Water use efficiency

Influence of location of large-scale asperity on shear strength of concrete-rock interface under eccentric load

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第3期12卷 449-460页

作者： Dipen Bista gabriel Sas Fredrik Johansson Leif Lia SINTEF Narvik As Narvik8517Norway Norwegian University of Science and Technology(NTNU) Trondheim7491Norway Royal Institute of Technology(KTH) Stockholm10044Sweden

The location and geometry of large-scale asperity present at the foundation of concrete gravity dams and buttress dams affect the shear resistance of the concrete-rock ***,the parameters describing the frictional resistance of the interface usually do not account for these *** could result in an underestimate of the peak shear stre ngth,which leads to significantly conservative design for new dams or unnecessary stability enhancing measures for existing *** aim of this work was to investigate the effect of the location of first-order asperity on the peak shear strength of a concrete-rock interface under eccentric load and the model discrepancy associated with the commonly used rigid body methods for calculating the factor of safety(FS)against *** this,a series of direct and eccentric shear tests under constant normal load(CNL)was carried out on concrete-rock *** peak shear strengths measured in the tests were compared in terms of asperity location and with the predicted values from analytical rigid body *** results showed that the large-scale asperity under eccentric load significantly affected the peak shear ***,unlike the conventional assumption of sliding or shear failure of an asperity in direct shear,under the effect of eccentric shear load,a tensile failure in the rock or in the concrete could occur,resulting in a lower shear strength compared with that of direct shear *** results could have important implications for assessment of the FS against sliding failure in the concrete-rock interface.

关键词： Shear strength Concrete-rock interface Asperity location Eccentric load Model discrepancy Dam foundation

Intraoperative cholangiography 2020:Quo vadis? A systematic review of the literature

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Hepatobiliary & Pancreatic Diseases International 2022年第2期21卷 145-153页

作者： Konstantinos Georgiou gabriel Sandblom Nicholas Alexakis Lars Enochsson First Department of Propaedeutic Surgery Hippokration General Hospital of AthensAthens Medical SchoolNational and Kapodistrian University of AthensAthens 10679Greece Department of Clinical Science and Education Department of SurgeryKarolinska InstitutetSödersjukhusetStockholm 17177SESweden Department of Surgical and Perioperative Sciences SurgeryUmeåUniversityUmeå90187SESweden

Background: There are few randomized controlled trials with sufficient statistical power to assess the effectiveness of intraoperative cholangiography(IOC) in the detection and treatment of common bile duct injury(BDI) or retained stones during cholecystectomy. The best evidence so far regarding IOC and reduced morbidity related to BDI and retained common bile duct stones was derived from large populationbased cohort studies. Population-based studies also have the advantage of reflecting the outcome of the procedure as it is practiced in the community at large. However, the outcomes of these population-based studies are conflicting. Data sources: A systematic literature search was conducted in 2020 to search for articles that contained the terms “bile duct injury”, “critical view of safety”, “bile duct imaging” or “retained stones” in combination with IOC. All identifed references were screened to select population-based studies and observational studies from large centers where socioeconomic or geographical selections were assumed not to cause selection bias. Results: The search revealed 273 references. A total of 30 articles fulflled the criteria for a large observational study with minimal risk for selection bias. The majority suggested that IOC reduces morbidity associated with BDI and retained common bile duct stones. In the short term, IOC increases the cost of surgery. However, this is offset by reduced costs in the long run since BDI or retained stones detected during surgery are managed immediately. Conclusions: IOC reduces morbidity associated with BDI and retained common bile duct stones. The reports reviewed are derived from large, unselected populations, thereby providing a high external validity. However, more studies on routine and selective IOC with well-defned outcome measures and sufficient statistical power are needed.

关键词： Cholangiography Cholecystectomy Bile duct stones Bile duct injury Cost

Magnetopause properties at the dusk magnetospheric flank from global magnetohydrodynamic simulations,the kinetic Vlasov equilibrium,and in situ observations--Potential implications for SMILE

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Earth and Planetary Physics 2024年第1期8卷 222-233页

作者： Marius Echim Costel Munteanu gabriel Voitcu Eliza Teodorescu Institute of Space Science Măgurele 077125Romania Royal Belgian Institute for Space Aeronomy 1180 BrusselsBelgium Solar-Terrestrial Centre of Excellence(STCE) 1180 BrusselsBelgium

We derived the properties of the terrestrial magnetopause(MP)from two modeling approaches,one global–fluid,the other local–kinetic,and compared the results with data collected in situ by the Magnetospheric Multiscale 2(MMS2)*** used global magnetohydrodynamic(MHD)simulations of the Earth’s magnetosphere(publicly available from the NASA-CCMC[National Aeronautics and Space Administration–Community Coordinated Modeling Center])and local Vlasov equilibrium models(based on kinetic models for tangential discontinuities)to extract spatial profiles of the plasma and field variables at the Earth’s *** global MHD simulations used initial solar wind conditions extracted from the OMNI database at the time epoch when the MMS2 observes the *** kinetic Vlasov model used asymptotic boundary conditions derived from the same in situ MMS measurements upstream or downstream of the *** global MHD simulations provide a three-dimensional image of the magnetosphere at the time when the MMS2 crosses the *** Vlasov model provides a one-dimensional local view of the MP derived from first principles of kinetic *** MMS2 experimental data also serve as a reference for comparing and validating the numerical simulations and *** found that the MP transition layer formed in global MHD simulations was generally localized closer to the Earth(roughly by one Earth radius)from the position of the real MP observed by the *** also found that the global MHD simulations overestimated the thickness of the MP transition by one order of magnitude for three analyzed variables:magnetic field,density,and tangential *** MP thickness derived from the local Vlasov equilibrium was consistent with observations for all three of these *** overestimation of density in the Vlasov equilibrium was reduced compared with the global MHD *** discuss our results in the context of future SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)campaigns for observing

关键词： magnetopause magnetohydrodynamic numerical simulations Vlasov equilibrium Magnetospheric Multiscale observations

Validity of continuous-failure-state unloading triaxial tests as a means to estimate the residual strength of rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第4期13卷 717-726页

作者： gabriel Walton Steven Gaines Leandro R.Alejano Department of Geology and Engineering Geology Colorado School of MinesGoldenCO80401USA Natural Resources Canada CanmetMININGOttawaOntarioK1A 1M1Canada Department of Natural Resources and Environmental Engineering Universidad de VigoVigo36310Spain

The residual strength of rocks and rock masses is an important parameter to be constrained for analysis and design purposes in many rock engineering applications.A residual strength envelope in principal stress space is typically developed using residual strength data obtained from compression tests on many different specimens of the same rock *** this study,we examined the potential for use of the continuous-failure-state testing concept as a means to constrain the residual strength envelope using a limited number of ***,cylindrical specimens of three rock types(granodiorite,diabase,and Stanstead granite)were unloaded at the residual state such that a full residual strength envelope for each individual specimen was *** a residual strength model that introduces a single new strength parameter(the residual strength index,or RSI),the results of the continuous-failurestate unloading tests were compared to conventionally obtained residual strength ***,the continuous-failure-state residual strength data were found to be consistent with the conventional residual strength ***,it was identified that the primary factor limiting an accurate characterization of the residual strength for a given rock type is not the amount of data for a given specimen,but the variety of specimens available to characterize the inherent variability of the rock unit of ***,the use of continuous-failure-state testing for estimation of the residual strength of a rock unit is only recommended when the number of specimens available for testing is very limited(i.e.<5).

关键词： Residual strength Continuous-failure-state testing Compression testing Brittle rock mechanics