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Atmospheric and kinetic studies of OH and HO_2 by the FAGE technique

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Journal of Environmental Sciences 2012年第1期24卷 78-86页

作者： D.Amedro K.Miyazaki a.parker C.Schoemaecker C.Fittschen Laboratoire PC2A Universit de Lille 1- Ba timent C1159655 Villeneuve d'AscqFrance Department of Applied Chemistry Tokyo Metropolitan UniversityJapan

A new FAGE setup has recently been built at the University of Lille,*** permits the quantification of OH and HO 2 in the atmosphere with a detection limit of 3×10 5 molecules/（cm 3 ·min） for OH and 1×10 6 molecules/（cm 3 ·min） for HO *** coupling to a photolysis cell enables the measurement of the total reactivity of the hydroxyl radical in ambient air and kinetic studies in *** configurations have been considered：one with the photolysis cell at 90° to the FAGE nozzle,the other on line with the FAGE *** two configurations have been tested and validated by measuring the well known rate constants of OH with CH 4,C 3 H 8 and *** advantages and drawbacks of each configuration have been *** ＂on line＂ configuration limits losses and permits measurements over a larger reactivity range but is affected by OH formation from the laser beam striking the FAGE nozzle,thus limiting the ability to carry out energy dependence studies which can,in contrast,be successfully performed in the 90° configuration.

关键词： OH kinetic reactivity laser induced fluorescence

Determination of the Normal Contact Stiffness and Integration Time Step for the Finite Element Modeling of Bristle-Surface Interaction

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Computers, Materials & Continua 2018年第7期56卷 169-184页

作者： Libardo V.Vanegas-Useche Magd M.Abdel-Wahab Graham a.parker Facultad de Ingeniería Mecánica Universidad Tecnológica de Pereira.Pereira 660003Colombia Division of Computational Mechanics Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityVietnam Soete Laboratory Faculty of Engineering and ArchitectureGhent UniversityTechnologiepark Zwijnaarde 903Zwijnaarde B-9052Belgium Faculty of Engineering and Physical Sciences University of Surrey.GuildfordUK

In finite element modeling of impact,it is necessary to define appropriate values of the normal contact stiffness,Kn,and the Integration Time Step(ITS).Because impacts are usually of very short duration,very small ITSs are ***,the selection of a suitable value of Kn is a critical issue,as the impact behavior depends dramatically on this *** this work,a number of experimental tests and finite element analyses have been performed in order to obtain an appropriate value of Kn for the interaction between a bristle of a gutter brush for road sweeping and a concrete ***,a suitable ITS is *** experiments consist of releasing a steel bristle that is placed vertically at a certain distance from a concrete surface and tracking the ***,in the finite element analyses,a beam is modeled in free fall and impacting a surface;contact and target elements are attached to the beam and the surface,*** results of the experiments and the modeling are integrated through the principle of conservation of energy,the principle of linear impulse and momentum,and Newton’s second *** results demonstrate that,for the case studied,Kn and the impact time tend to be independent of the velocity just before impact and that Kn has a very large variation,as concrete is a composite material with a rough ***,the ratio between the largest height of the bristle after impact and the initial height tends to be constant.

关键词： Brush street sweeping finite element modeling contact mechanics

Numerical Analysis of Tilted Cutting and F128 Brushes

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Computer Modeling in Engineering & Sciences 2019年第10期121卷 23-47页

作者： Libardo V.Vanegas-Useche Magd M.Abdel-Wahab Graham a.parker Facultad de Ingeniería Mecánica Universidad Tecnológica de PereiraLa JulitaPereira 660003Colombia Division of Computational Mechanics Ton Duc Thang UniversityHo Chi Minh CityViet Nam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityViet Nam Soete Laboratory Faculty of Engineering and ArchitectureGhent UniversityTechnologiepark Zwijnaarde 46B-9052 ZwijnaardeBelgium Faculty of Engineering and Physical Sciences University of Surrey.Guildford GU27XHUK.

Road sweeping is an essential service that has to be conducted for public health,as well as aesthetic *** many countries,sweeping vehicles are used for this *** usually comprise a gutter brush that sweeps the debris that is located in the road *** work studies the performance of two kinds of gutter brushes:a cutting brush and a flicking(F128)*** is carried out by means of a 3-D dynamic,nonlinear Finite Element(FE)brush model developed by the *** this model,inertia forces are applied to the bristle,and its clamped end is ***,the surface(road)is rotated,translated,and ***-road interaction is modelled as flexible-to-rigid *** particular,the aim of this article is to compare the performance of a conventional brush and a brush rotating at variable *** brushes normally work tilted,FE analyses are carried out for tilted cutting and F128 brushes,rotating at speeds that fluctuate at different *** is concluded that brush oscillations have a significant effect on bristle tip velocities and bristle-road ***,at certain frequencies,oscillations seem to improve sweeping performance of the F128 ***,they do not appear to improve significantly the performance of the cutting brush.

关键词： Gutter brushes cutting brush flicking brush FEM variable speed brushing

The lncRNA BORG: a novel inducer of TNBC metastasis, chemoresistance, and disease recurrence

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Journal of Cancer Metastasis and Treatment 2019年第5期4卷 48-61页

作者： Alex J.Gooding Kimberly a.parker Saba Valadkhan William P.Schiemann Department of Pathology Case Western Reserve UniversityClevelandOH 44106USA Department of Pharmacology Case Western Reserve UniversityClevelandOH 44106USA Department of Molecular Biology and Microbiology Case Western Reserve UniversityClevelandOH 44106USA Case Comprehensive Cancer Center Case Western Reserve UniversityClevelandOH 44106USA

Although greater than 90% of breast cancer-related mortality can be attributed to metastases, the molecular mechanisms underpinning the dissemination of primary breast tumor cells and their ability to establish malignant lesions in distant tissues remain incompletely understood. Genomic and transcriptomic analyses identified a class of transcripts called long noncoding RNA (lncRNA), which interact both directly and indirectly with key components of gene regulatory networks to alter cell proliferation, invasion, and metastasis. We identified a pro-metastatic lncRNA BMP/OP-Responsive Gene (BORG) whose aberrant expression promotes metastatic relapse by reactivating proliferative programs in dormant disseminated tumor cells (DTCs). BORG expression is broadly and strongly induced by environmental and chemotherapeutic stresses, a transcriptional response that facilitates the survival of DTCs. Transcriptomic reprogramming in response to BORG resulted in robust signaling via survival and viability pathways, as well as decreased activation of cell death pathways. As such, BORG expression acts as a (1) marker capable of predicting which breast cancer patients are predisposed to develop secondary metastatic lesions;and (2) unique therapeutic target to maximize chemosensitivity of DTCs. Here we review the molecular and cellular factors that contribute to the pathophysiological activities of BORG during its regulation of breast cancer metastasis, chemoresistance, and disease recurrence.

关键词： BORG chemoresistance disease recurrence dormancy long noncoding RNA metastasis triple-negative breast cancer

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Journal of Green Building 2006年第4期1卷 141-151页

作者： a.parker M.Aschheim D.Mar M.Hammer B.King Dept.of Civil Engineering Santa Clara UniversitySanta ClaraCA 95053 Tipping-Mar+Associates BerkeleyCA 94704 不详

Experimental studies on full-scale straw-bale walls have demonstrated the adequacy of straw-bale wall systems for resisting lateral loads from wind or seismic *** to the performance of the wall system is the anchorage of mesh reinforcement to the bottom plate and to the roof bearing assembly or top *** in this paper are the results of experiments examining mesh strength,anchorage strength,and failure mode for a variety of reinforcement meshes(steel,plastic,and hemp)and anchorage *** of the potential for new wood preservative pressure treatments to cause corrosion,stainless steel staples driven pneumatically into pressure-treated sill plates were tested in addition to electro-galvanized staples driven pneumatically into untreated sill plates and a heavier gauge staple driven manually into an untreated sill *** anchorage details are identified,considering not only the test results but also the many other factors that must be considered in developing reliable,economical,and constructible details.

关键词： straw bale mesh details mesh anchorage mesh strength staples

Artificial light at night(ALAN) pollution alters bat lunar chronobiology:insights from broad-scale long-term acoustic monitoring

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Ecological Processes 2024年第1期13卷 176-187页

作者： Han Li Pauline Allen Saige Boris Samantha Lagrama Jade Lyons Christina Mills Pauline Moussi Casey Nichols Carter Tacosik Mc Kenzie Tsaousis Nyzaya Livingston Wilson John F.Grider Kevin a.parker Matina C.Kalcounis-Rueppell Department of Biology University of Nebraska Omaha Department of Biology University of North Carolina Greensboro Colorado Parks and Wild-life parker Ecology LLC Department of Biological Sciences University of Alberta

Background The timing of behavior and habitat use of nocturnal animals can be influenced by the lunar cycle in nature. The prevalence of artificial light at night(ALAN) has been recognized as a source of environmental pol-lution. The interaction between ALAN and the lunar cycle on bat behavior is important for understanding anthro-pogenic effects on bats. We utilized a decade(2012–2022) of acoustic monitoring data collected in North Carolina, United States, to investigate the relationship between bat activity, lunar cycle, and light pollution. We examined whether the amount of lunar illumination affected species-specific nightly activity and whether hourly bat activity patterns varied between nights with different moon phases. We further investigated if the relationship between bat activity and the lunar cycle might be altered by light *** We found that seven bat species showed activity variation across nights in relation to the amount of moon illumination when ALAN was absent. In general, bats were less active on full moon nights compared to new moon nights. Light pollution interacted with the bat–lunar relationship in five of the seven species, masking the effect of the lunar cycle. We identified delayed bat activity patterns on nights with a full or waxing moon in seven species, and light pollution altered that pattern in four species. Overall, ALAN was associated with decreased bat activity inde-pendent of lunar cycle *** Our study demonstrated that at a broad spatial scale, ALAN negatively affected many North American temperate bat species and altered their lunar chronobiology. As light pollution is spreading to historically dark areas and habitats, ALAN might couple with other threats, such as the white-nose syndrome or climate change, to cause cascading damage in the environment that depends on ecosystem services such as pest control provided by bats. We argue that further research and conservation actions are needed to mitigate

关键词： Artificial light at night ALAN Bats Chiroptera Chronobiology Light pollution Lunar cycle Moonlight