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Model-based framework for multi-axial real-time hybrid simulation testing

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Earthquake Engineering and Engineering Vibration 2017年第4期16卷 671-691页

作者： gaston A.Fermandois Billie F.Spencer,Jr. Department of Civil and Environmental Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA

Real-time hybrid simulation is an efficient and cost-effective dynamic testing technique for performance evaluation of structural systems subjected to earthquake loading with rate-dependent behavior. A loading assembly with multiple actuators is required to impose realistic boundary conditions on physical specimens. However, such a testing system is expected to exhibit significant dynamic coupling of the actuators and suffer from time lags that are associated with the dynamics of the servo-hydraulic system, as well as control-structure interaction （CSI）. One approach to reducing experimental errors considers a multi-input, multi-output （MIMO） controller design, yielding accurate reference tracking and noise rejection. In this paper, a framework for multi-axial real-time hybrid simulation （maRTHS） testing is presented. The methodology employs a real-time feedback-feedforward controller for multiple actuators commanded in Cartesian coordinates. Kinematic transformations between actuator space and Cartesian space are derived for all six-degrees-of- freedom of the moving platform. Then, a frequency domain identification technique is used to develop an accurate MIMO transfer function of the system. Further, a Cartesian-domain model-based feedforward-feedback controller is implemented for time lag compensation and to increase the robustness of the reference tracking for given model uncertainty. The framework is implemented using the 1/5th-scale Load and Boundary Condition Box （LBCB） located at the University of Illinois at Urbana- Champaign. To demonstrate the efficacy of the proposed methodology, a single-story frame subjected to earthquake loading is tested. One of the columns in the fraane is represented physically in the laboratory as a cantilevered steel column. For real- time execution, the numerical substructure, kinematic transformations, and controllers are implemented on a digital signal processor. Results show excellent performance of the maRTHS framework when

关键词： real-time hybrid simulation multiple actuators dynamic coupling kinematic transformations model-basedcompensation

Dual regulation of SnRK2 signaling by Raf-like MAPKKKs

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Molecular Plant 2022年第8期15卷 1260-1262页

作者： gaston A.Pizzio Pedro L.Rodriguez Institutode Biologia Molecular y Celularde Plantas Consejo Superior de Investigaciones Cientificas-Universidad Politecnica de Valencia46022 ValenciaSpain

Plants must adapt to unfavorable growth conditions such as drought,salinity,or extreme temperature and,in addition,need the flexibility to resume growth when conditions become *** of extracellular environmental stress and signal transduction rely on pathways that in many cases use phosphorylation of target proteins to amplify and transmit the extracellular signal.

关键词： SnRK2 extracellular resume

Impacts of mobile phone use while driving on the performance of petroleum product drivers in Cameroon

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Transportation Safety and Environment 2023年第2期5卷 14-26页

作者： Elisee-Enselme Tuekam-Bopda Jean gaston Tamba Armand Fopah-Lele Transports and Applied Logistics Laboratory University Institute of TechnologyUniversity of DoualaP.O.Box 8698DoualaCameroon Department of Thermal and Energy Engineering University Institute of TechnologyUniversity of DoualaP.O.Box 8698DoualaCameroon Department of Mechanical Engineering University of BueaP.O.Box 63BueaCameroon

The objective of this article is to show the influence of mobile phone use while driving on the performance of petroleum product drivers in *** topical questioning centred on the series of accidents and near misses in general and specifically in the petroleum products sector and showed the need to look for other *** do so,we conceptually proposed a model derived from the literature review and adjusted by practical research,which shows that our approach is the hypothetico-deductive ***,the observations from the experience of 90 questionnaires were operationalized using multivariate logistic regression *** results indicate that making or receiving calls while driving significantly influences the occurrence of reckless driving *** and sending short message service(SMS or text messages)while driving negatively influences drivers’performance by increasing delivery *** type of phone used has an effect on the risk of accidents or near ***,drivers who use smartphones are 2.14 times more likely to experience crash-like events compared to those who use conventional mobile *** addition,with a view to reducing near misses and accidents,it is important to organize regular appropriate road safety campaigns,to install on-board cameras in all trucks,to provide rest areas and encourage drivers to stop at these areas to check their phones and catch up on missed *** to introduce training for drivers in defensive driving with a renewable licence after a maximum of 2 years.

关键词： mobilephone quasi-accident multivariate analysis impact near miss reading text messages while driving answering calls while driving

Exploring impacts of COVID-19 on spatial and temporal patterns of visitors to Canadian Rocky Mountain National Parks from social media big data

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Journal of Forestry Research 2024年第4期35卷 13-33页

作者： Dehui Christina Geng Amy Li Jieyu Zhang Howie W.Harshaw Christopher gaston Wanli Wu Guangyu Wang National Park Research Centre Faculty of ForestryUniversity of British ColumbiaVancouver V6T 1Z4Canada Faculty of Applied Science University of British ColumbiaVancouver V6T 1Z3Canada Paul G.Allen School of Computer Science&Engineering University of WashingtonSeattleWA 98195USA Faculty of Kinesiology Sportand RecreationUniversity of AlbertaEdmonton T6G 2J9Canada Department of Wood Science Faculty of ForestryUniversity of British ColumbiaVancouver V6T 1Z4Canada

COVID-19 posed challenges for global tourism *** in visitor temporal and spatial patterns and their associated determinants pre-and peri-pandemic in Canadian Rocky Mountain National Parks are *** was collected through social media programming and analyzed using spatiotemporal analysis and a geographically weighted regression(GWR)*** highlight that COVID-19 significantly changed park visitation *** tended to explore more remote areas *** GWR model also indicated distance to nearby trails was a significant influence on visitor *** results indicate that the pandemic influenced tourism temporal and spatial *** research presents a novel approach using combined social media big data which can be extended to the field of tourism management,and has important implications to manage visitor patterns and to allocate resources efficiently to satisfy multiple objectives of park management.

关键词： Tourism management Social media big data National parks COVID-19 Geographical weighted regression

Relationship between antibacterial activity of chitosan and surface characteristics of cell wall

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Acta Pharmacologica Sinica 2004年第7期25卷 86-90页

作者： Ying-chien CHUNG,Chiing-chang CHEN,Huey-lan WANG,J C gaston WU,Jaung-geng LIN Department of Industrial Engineering and Management China Institute of Technology Taipei 245 China Department of GeneralStudies NationalTaichung Nursing College Taichung 403 China Basic Medical Science Education Center Fooyin University Kaohsiung 831 China Department of Chemistry National Taiwan Normal University Taipei 116 China Institute of Chinese Medical Science China Medical University Taichung 404 China

AIM: Five representative waterborne pathogens were used to illustrate the relationship between chitosan’s antibac- terial activity and the surface characteristics of the bacterial cell wall. METHODS: Chitosan was prepared with averaged 75 % or 95 % deacetylated degree to examine its antibacterial activity against waterborne pathogens. Fresh microbial inoculants for the antibacterial assessment were prepared on nutrient agar at 37oC for 24 h. The evaluation items of antibacterial mechanism included hydrophilicity and negative charge analysis of cell surface, and adsorptive characteristics of chitosan to bacterial cell. All the experiments were applied in triplicate tests at least. RESULTS: Although cell wall hydrophilicity was similar among Gram-negative bacteria, the distribution of negative charge on their cell surfaces was quite different. More negatively charged cell surfaces had a greater interaction with chitosan, a phenomenon further confirmed by transmission electron micrography (TEM). CONCLUSION: Results showed the hydrophilicity in Gram-negative bacteria was much higher than in Gram-positive ones. The correlation coefficient 0.988 between the amount of absorbed chitosan and its inhibition efficiency indicated a close relationship.

关键词： anti-bacterial agents chitosan cell wall

Lack of functional link in the tadpole morphology induced by predators

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Current Zoology 2016年第3期62卷 227-235页

作者： Maria Gabriela PEROTTI Mariana PUETA Fabian gaston JARA Carmen Adria UBED Debora Lina MORENO AZOCAR Laboratorio de Fotobiologfa INIBIOMA CONICET-Universidad Nacional del Comahue O.uintral 1250 Bariloche Rio Negro Argentina Departamento de Biologfa General. Universidad Nacional del Comahue Quintral 1250 Bariloche Rio Negro Argentina Departamento de Zoologia INIBIOMA CONICET-Universidad Nacional del Comahue Quintral 1250 8400 Bariloche Rio Negro Argentina

Most studies of predator-induced plasticity have focused on documenting how prey species re- spond to predators by modifying phenotypic traits and how traits correlate with fitness. We have previously shown that Pleurodema thaul tadpoles exposed to the dragonfly Rhionaeschna varie- gata responded strongly by showing morphological changes, less activity, and better survival than non-exposed tadpoles. Here, we tested whether there is a functional link between morphological plasticity and increased survival in the presence of predators. Tadpoles that experienced predation risk were smaller, less developed, and much less active than tadpoles without this experience. Burst speed did not correlate significantly with morphological changes and predator-induced deeper tails did not act as a lure to divert predator strikes away from the head. Although we have previously found that tadpoles with predator-induced morphology survive better under a direct predator threat, our results on the functional link between morphology and fitness are not conclu- sive. Our results suggest that in P. thaultadpoles （1） burst speed is not important to evade preda- tors, （2） those exposed to predators reduce their activity, and （3） morphological changes do not divert predator attacks away from areas that compromise tadpole survivalEE. Our results show that morphological changes in P. thaul tadpoles do not explain burst speed or lure attraction, al- though there was a clear reduction of activity, which itself reduces predation. We propose that changes in tadpole activity could be further analyzed from another perspective, with morphological change as an indirect product of behavior mediated by physiological mechanisms.

关键词： induced morphology lure effect predator exposure swimming performance tadpoles.

Analysis of per-and polyfluoroalkyl substances in Houston Ship Channel and Galveston Bay following a large-scale industrial fire using ion-mobility-spectrometry-mass spectrometry

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Journal of Environmental Sciences 2022年第5期34卷 350-362页

作者： Alan Valdiviezo Noor AAly Yu-Syuan Luo Alexandra Cordova gaston Casillas MaKayla Foster Erin SBaker Ivan Rusyn Interdisciplinary Faculty of Toxicology Texas A&M UniversityCollege StationTX 77843USA Department of Veterinary Integrative Biosciences Texas A&M UniversityCollege StationTX 77843USA Department of Environmental and Occupational Health Texas A&M UniversityCollege StationTX 77843USA Department of Chemistry North Carolina State UniversityRaleighNC 27695USA

Per-and polyfluoroalkyl substances(PFAS)are persistent organic pollutants of concern be-cause of their ubiquitous presence in surface and ground water;analytical methods that can be used for rapid comprehensive exposure assessment and fingerprinting of PFAS are *** the fires at the Intercontinental Terminals Company(ITC)in Deer Park,TX in 2019,large quantities of PFAS-containing firefighting foams were *** release of these substances into the Houston Ship Channel/Galveston Bay(HSC/GB)prompted con-cerns over the extent and level of PFAS contamination.A targeted liquid chromatography-tandem mass spectrometry(LC-MS/MS)-based study of temporal and spatial patterns of PFAS associated with this incident revealed presence of 7 species;their levels gradually de-creased over a 6-month *** the targeted LC-MS/MS analysis was focused on about 30 PFAS molecules,it may have missed other PFAS compounds present in firefighting ***,we utilized untargeted LC-ion mobility spectrometry-mass spectrome-try(LC-IMS-MS)-based analytical approach for a more comprehensive characterization of PFAS in these water *** analyzed 31 samples from 9 sites in the HSC/GB that were collected over 5 months after the *** data showed that additional 19 PFAS were detected in surface water of HSC/GB,most of them decreased gradually after the *** features detected by LC-MS/MS correlated well in abundance with LC-IMS-MS data;however,LC-IMS-MS identified a number of additional PFAS,many known to be compo-nents of firefighting *** findings therefore illustrate that untargeted LC-IMS-MS improved our understanding of PFAS presence in complex environmental samples.

关键词： Emergency Environmental disaster PFAS

Plant H^＋-PPases： Reversible Enzymes with Contrasting Functions Dependent on Membrane Environment

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Molecular Plant 2016年第3期9卷 317-319页

作者： Roberto A. Gaxiola Kamesh Regmi Julio Paez-Valencia gaston Pizzio Shangji Zhang School of Life Sciences Arizona State University 427 E. Taylor Mall Tempe AZ 852872 USA Department of Botany University of Wisconsin Madison WI 53706 USA Centre de Recerca en Agrigenomica (CRAG) Consorcio CSIC-IRTA-UAB-UB Parc de Recerca de la UAB C/de la Vail Moronta Edifici CRAG Bellaterra (Cerdanyola del Valles) 08193 Barcelona Spain

Plant proton-translocating pyrophosphatases （H^＋-PPases） are generally thought of as tonoplast-localized proton pumps that utilize the energy released by hydrolysis of the phosphoanhydride bond of pyrophosphate （PPi） to assist in the acidification of the *** has been suggested that H^＋-PPases function as an additional acidification mechanism to complement the ubiquitous V-ATPase,especially in young,growing tissues where PPi is abundant and ATP is depleted （Shiratake et al.,1997）.

关键词： additional especially conserved

Integrated Future Needs and Climate Change on the River Niger Water Availability

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Journal of Water Resource and Protection 2013年第9期5卷 887-893页

作者： gaston Lienou Departement of Earth Sciences University of Yaounde I Yaounde Cameroon

The river Niger is the 3rd longest river in Africa, with a stream length of 4200 km, a drainage basin of 2,170,500 km2 of which 1,500,000 km2 is an active basin, and an average discharge of about 6000 m3/s. The natural variability of its rainfall and discharge is analyzed for several major sub-basins, in the context of the West African drought which has lasted for nearly 40 years, showing two paradoxes: the increase of Sahelian runoff since the beginning of the drought due to land degradation, and the steep decrease of sudanian runoff over the same period, substantiated by the long-lasting decrease of the groundwater tables. Much information about the water resources available in the basin is collected and analysed by the NBA1, which is summarized in this paper including surface water resources, rainfall over the basin, existing and projected dams. The river Niger is deficient in dams to control water, especially in its upper and middle basins. Nigeria has many dams, including large dams, while Burkina Faso has many small dams, but there are only a few dams upstream of the river Niger in Mali/Guinea/Ivory Coast. It is therefore likely that several dams will be built in the Niger basin in the coming years, and several are in the project phase. All of these will have a large impact on the river Niger regime and the environment, especially the Fomi dam which will change significantly the river regime upstream of the inner Delta, inducing an important reduction of the flooded area, and the Tossaye dam on the Saharan border of Mali which could promote a very significant level of evaporation. It is very important before building these dams to take into account the past years variability of climate and river regime.

关键词： Drought River Niger Sahel Desert Water Resources Water Accessibility