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Implicit large eddy simulation of unsteady cloud cavitation around a plane-convex hydrofoil

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Journal of Hydrodynamics 2015年第6期27卷 815-823页

作者： hidalgo Victor 罗先武 ESCALER Xavier 季斌 AGUINAGA Alvaro Beijing Key Laboratory of CO2 Utilization and Reduction Technology Tsinghua University CDIF Universitat Politècnica de Catalunya School of Power and Mechanical Engineering Wuhan University Mechanical Engineering Department Escuela Politecnica Nacional University

The present paper focuses on the erosive cavitation behavior around a plane convex hydrofoil. The Zwart-Gerber-Belamri cavitation model is implemented in a library form to be used with the OpenFOAM. The implicit large eddy simulation （ILES） is app- lied to analyze the three-dimensional unsteady cavitating flow around a plane convex hydrofoil. The numerical results in the cases under the hydrodynamic conditions, which were experimentally tested at the high speed cavitation tunnel of the l^cole Polytechnique F6d＆ale de Lausanne （EPFL）, clearly show the sheet cavitation development, the shedding and the collapse of vapor clouds. It is noted that the cavitation evolutions including the maximum vapor length, the detachment and the oscillation frequency, are captured fairly well. Furthermore, the pressure pulses due to the cavitation development as well as the complex vortex structures are reasona- bly well predicted. Consequently, it may be concluded that the present numerical method can be used to investigate the unsteady cavitation around hydrofoils with a satisfactory accuracy.

关键词： implicit large eddy simulation (ILES) unsteady partial cavitation Zwart-Gerber-Belamri cavitation model OpenFOAM,Q - criterion

Evaluation of design schemes for urban squares in arid climate cities,Mendoza,Argentina

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Building Simulation 2021年第3期14卷 763-777页

作者： Susana Stocco Maria alicia Canton Erica Correa INAHE-Instituto de Ambiente Habitat yEnergia-CONICETMendozaArgentina

The design of urban squares in the city of Mendoza,Argentina,is based on aesthetic and landscaping criteria without consider strategies to enhance the benefits that green areas generate on the city's micrometeorological *** paper aims to evaluate different design alternatives with the purpose to determine which proportion and distribution of green and sealed areas contributes to achieve the best conditions in terms of thermal behavior and ***-met software was used to simulate thermal conditions over twenty three scenarios,and COMFA method was employed to determine comfort in the scenarios that show the best thermal behaviour and are representative of current design *** results show that the most effective scheme for the memorial squares rehabilitation is the one concentrating 60%of woodlot around a sealed center with an area that does not exceed 20%the square *** effective alternative is the one concentrating 60%of woodlot at the center of the *** findings highlight the importance of an adequate relation between proportion and distribution of woodlot/sealed areas to improve thermal performance and comfort conditions of open spaces.

关键词： design of urban squares effective scheme of design alternativas de diseno proportion green/sealed distribution green/sealed

Lysine Acetylation and Deacetylation in Brain Development and Neuropathies

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Genomics, Proteomics & Bioinformatics 2017年第1期15卷 19-36页

作者： alicia Tapias Zhao-Qi Wang Leihniz Institute on Aging Fritz Lipmann Institute(FLI) 07745 JenaGermany Faculty of Biology and Pharmacy Friedrich Schiller University of Jena07743 JenaGermany

Embryonic development is critical for the final functionality and maintenance of the adult brain. Brain development is tightly regulated by intracellular and extracellular signaling. Lysine acetylation and deacetylation are posttranslational modifications that are able to link extracellular signals to intracelhdar responses. A wealth of evidence indicates that lysine acetylation and deacetylation are critical for brain development and functionality. Indeed, mutations of the enzymes and cofactors responsible for these processes are often associated with neurodevelopmental and psychiatric disorders. Lysine acetylation and deacetylation are involved in all levels of brain development, starting from neuroprogenitor survival and proliferation, cell fate decisions, neuronal maturation, migration, and synaptogenesis, as well as differentiation and maturation of astrocytes and oligodendrocytes, to the establishment of neuronal circuits. Hence, fluctuations in the balance between lysine acetylation and deacetylation contribute to the final shape and perrformance of the brain. In this review, we summarize the current basic knowledge on the specific roles of lysine acetyltransferase （KAT） and lysine deacetylase （KDAC） complexes in brain development and the different neurodevelopmental disorders that are associated with dysfunctional lysine （de）acetylation machineries.

关键词： KAT KDAC:Neural stem cells/neuroprogenitors Neurogenesis Neurodevelopmentaldisorders

Eelgrass and Macroalgae Loss in an Oregon Estuary: Consequences for Ocean Acidification and Hypoxia

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Ocean-Land-Atmosphere Research 2023年第1期2卷 267-284页

作者： Caitlin L.Magel Sally D.Hacker Francis Chan alicia R.Helms Department of Integrative Biology Oregon State UniversityCorvallisOR 97331USA South Slough National Estuarine Research Reserve CharlestonOR 97420USA.

Estuarine macrophytes are proposed to influence ocean acidification and hypoxia(OAH)via the uptake(release)of inorganic carbon(oxygen)during *** extent to which macrophytes mitigate OAH in estuaries depends on the interaction between variable environmental conditions and macrophyte production over space and *** explore these complexities in detail,we considered the potential causes and consequences of intertidal eelgrass and macroalgae declines in a *** Northwest *** compiled and analyzed a record of eelgrass(Zostera marina)and ulvoid macroalgae along with a broad suite of environmental conditions over 15 years(2004 to 2019)at 3 sites along an estuarine gradient in South Slough,*** analysis showed that declining macrophyte biomass coincided with increasing temperature(water and air),watershed disturbance,and possibly *** with macrophyte loss,diel dissolved oxygen(DO)and pH variability were reduced,indicating an influence of macrophytes on water quality at an ecosystem *** loss was correlated with declining gross production and respiration,which altered the diel dynamics of pH,DO,and partial pressure of carbon dioxide at some *** certain conditions,there was an association between eelgrass biomass and changes in DO and pH of more than 2 mg/l and 0.3 units,*** found that daytime amelioration of low DO and pH was possible at certain locations when macrophyte biomass(especially eelgrass)was ***,our analyses suggested that the efficacy of macrophyte mitigation of OAH depends on macrophyte abundance and the volume and residence time of overlying water.

关键词： Estuary Northwest estuary

COVID‑19 and tourism sector stock price in Spain:medium‑term relationship through dynamic regression models

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Financial Innovation 2023年第1期9卷 257-280页

作者： Isabel Carrillo‑hidalgo Juan Ignacio Pulido‑Fernández JoséLuis Durán‑Román Jairo Casado‑Montilla Laboratory of Analysis and Innovation in Tourism University of JaénParaje Las Lagunillas S/ND3‑13423071 JaénSpain Laboratory of Analysis and Innovation in Tourism University of JaénParaje Las Lagunillas S/ND3‑27323071 JaénSpain Laboratory of Analysis and Innovation in Tourism University of JaénParaje Las Lagunillas S/ND3‑21723071 JaénSpain

The global pandemic,coronavirus disease 2019(COVID-19),has significantly affected tourism,especially in Spain,as it was among the first countries to be affected by the pandemic and is among the world’s biggest tourist *** market values are responding to the evolution of the pandemic,especially in the case of tourist ***,being able to quantify this relationship allows us to predict the effect of the pandemic on shares in the tourism sector,thereby improving the response to the crisis by policymakers and ***,a dynamic regression model was developed to predict the behavior of shares in the Spanish tourism sector according to the evolution of the COVID-19 pandemic in the medium *** has been confirmed that both the number of deaths and cases are good predictors of abnormal stock prices in the tourism sector.

关键词： COVID-19 Stock exchange Tourism stock Dynamic regression models Spain

Sex chromosomes behavior and G-banding treatment of male meiosis in nuptial gift-giving spiders of the family Trechaleidae

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Integrative Zoology 2011年第1期6卷 56-62页

作者： Maria J.ALBO alicia POSTIGLIONI Laboratory of Ethology Ecology and EvolutionClemente Estable Biological Research InstituteMontevideoUruguay Department of Genetics and Animal Breeding Faculty of VeterinaryUniversity of the RepublicMontevideoUruguay

Preliminary genetic studies in Trechaleidae spider family show high variation in sex chromosomes and high heterocigocity,suggesting high chromatin *** trechaleids Paratrechalea ornata,Trechalea bucculenta and Trechaleoides biocellata are present in *** offering nuptial gifts during courtship have been reported in *** and *** but not in *** gifts are an inherited trait probably highly affected by environmental factors,which play an important role in gene *** hypothesize that this trait could be associated with tissue-specific genes existing in *** investigate the male meiosis in these 3 species,their sex chromosome system and the effects of G-banding on their chromosomes,and elucidate genetic differences among *** stages of the 3 species were submitted to Giemsa-staining and G-banding *** observed a haploid number of n=11 in *** and n=13 in both *** and *** from the 3 species presented an X_(1)X_(2)0 sex chromosome system,which is suggested as ancestral in *** *** and ***,both sex chromosomes were together and aligned in parallel until the segregation during anaphase *** contrast to these species,sex chromosomes of *** usually remained distant from each other until diakinesis when they were observed associated in parallel *** G-bands were similar in *** and ***,and they both differed from those in *** special behavior of sex chromosomes in *** as well as the different G-banding pattern of this species suggests the existence of novel modifications in this species.

关键词： G-banding male meiosis Neotropical spiders sex chromosomes Trechaleidae

Interaction of silver nanoparticles with mediterranean agricultural soils: Lab-controlled adsorption and desorption studies

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Journal of Environmental Sciences 2019年第9期31卷 205-216页

作者： Laura Torrent Eva Margui Ignasi Queralt Manuela hidalgo Monica Iglesias Department of Chemistry University of Girona C/M. Aurelia Capmany 69 17003 Girona Spain Institute of Environmental Assessment and Water Research (IDAEA-CSIC) C. Jordi Girona 28-26 08034 Barcelona Spain

The production of silver nanoparticles(AgNPs) has increased tremendously during recent years due to their antibacterial and physicochemical properties. As a consequence, these particles are released inevitably into the environment, with soil being the main sink of disposal. Soil interactions have an effect on AgNP mobility, transport and bioavailability. To understand AgNP adsorption processes, lab-controlled kinetic studies were *** tests performed with five different Mediterranean agricultural soils showed that cation exchange capacity and electrical conductivity are the main parameters controlling the adsorption processes. The adsorption kinetics of different sized(40, 75, 100 and 200 nm)and coated(citrate, polyvinylpyrrolidone and polyethyleneglycol(PEG)) AgNPs indicated that these nanoparticle properties have also an effect on the adsorption *** assess the mobility and bioavailability of AgNPs and to determine if their form is maintained during adsorption/desorption processes, loaded soils were submitted to leaching tests three weeks after batch adsorption studies. The DIN 38414-S4 extraction method indicated that AgNPs were strongly retained on soils, and single-particle inductively coupled plasma mass spectrometry confirmed that silver particles maintained their nanoform, except for 100 nm PEG-AgNPs and 40 nm citrate-coated AgNPs. The DTPA(diethylenetriaminepentaacetic acid) leaching test was more effective in extracting silver,but there was no presence of AgNPs in almost all of these leachates.

关键词： Silver nanoparticles Agricultural soils Sorption kinetics Leaching tests Single-particle inductively coupled plasma mass spectrometry

Discretized Miller approach to assess effects on boundary layer ingestion induced distortion

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Chinese Journal of Aeronautics 2017年第1期30卷 235-248页

作者： Esteban Valencia Víctor hidalgo Devaiah Nalianda Laskaridis Panagiotis Riti Singh Departamento de Ingeniería Mecánica Facultad de Ingeniería Mecánica Escuela Politécnica Nacional Ladron de Guevara E11-253 Quito 17-01-2759 Ecuador School of Engineering Cranfield University Bedford MK430AL United Kingdom

The performance of propulsion configurations with boundary layer ingestion（BLI） is affected to a large extent by the level of distortion in the inlet flow field. Through flow methods and parallel compressor have been used in the past to calculate the effects of this aerodynamic integration issue on the fan performance; however high-fidelity through flow methods are computationally expensive, which limits their use at preliminary design stage. On the other hand, parallel compressor has been developed to assess only circumferential distortion. This paper introduces a discretized semi-empirical performance method, which uses empirical correlations for blade and performance calculations. This tool discretizes the inlet region in radial and circumferential directions enabling the assessment of deterioration in fan performance caused by the combined effect of both distortion patterns. This paper initially studies the accuracy and suitability of the semiempirical discretized method by comparing its predictions with CFD and experimental data for a baseline case working under distorted and undistorted conditions. Then a test case is examined,which corresponds to the propulsor fan of a distributed propulsion system with BLI. The results obtained from the validation study show a good agreement with the experimental and CFD results under design point conditions.

关键词： BLI Correlations Distortion Embedded propulsors Empirical Mean-line analysis Turbomachinery

Forest Biodiversity Assessment in Peruvian Andean Montane Cloud Forest

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Journal of Mountain Science 2012年第3期9卷 372-384页

作者： alicia Ledo Sonia Condés Iciar Alberdi Universidad Politécnica de Madrid.Escuela Técnica Superior de Ingenieros de Montes.Ciudad Universitaria sn.28040MadridSpain CIFOR-INIA Ctra.de La Corua Km 7.5 28040MadridSpain

Cloud forests are unusual and fragile habitats, being one of the least studied and least understood ecosystems. The tropical Andean dominion is considered one of the most significant places in the world as regards biological diversity, with a very high level of endemism. The biodiversity was analysed in an isolated remnant area of a tropical montane cloud forest known as the "Bosque de Neblina de Cuyas", in the North of the Peruvian Andean range. Composition, structure and dead wood were measured or estimated. The values obtained were compared with other cloud forests. The study revealed a high level of forest biodiversity, although the level of biodiversity differs from one area to another: in the inner areas, where human pressure is almost inexistent, the biodiversity values increase. The high species richness and the low dominance among species bear testimony to this montane cloud forest as a real enclave of biodiversity.

关键词：森林生物多样性云雾高山秘鲁评估物种丰富度生态系统特有现象