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IEEE/CAA journal of Automatica Sinica 2014年第3期1卷 294-301页

作者： mark j.Balas Susan A.Frost the Embry-Riddle Aeronautical University the NASA Ames Research Center

This paper is focused on adaptively controlling a linear infinite-dimensional system to track a finite-dimensional reference *** a linear continuous-time infinite-dimensional plant on a Hilbert space with disturbances of known waveform but unknown amplitude and phase,we show that there exists a stabilizing direct model reference adaptive control law with the properties of certain disturbance rejection and *** plant is described by a closed,densely defined linear operator that generates a continuous semigroup of bounded operators on the Hilbert space of *** central result will show that all errors will converge to a prescribed neighborhood of zero in an infinitedimensional Hilbert *** result will not require the use of the standard Barbalat’s lemma which requires certain signals to be uniformly *** result is used to determine conditions under which a linear infinite-dimensional system can be directly adaptively controlled to follow a reference *** particular,we examine conditions for a set of ideal trajectories to exist for the tracking *** results are applied to adaptive control of general linear diffusion systems described by self-adjoint operators with compact resolvent.

关键词： Robustness Adaptation models Adaptive control Hilbert space Trajectory Learning (artificial intelligence)

Are sperm capacitation and apoptosis the opposite ends of a continuum driven by oxidative stress？

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Asian journal of Andrology 2015年第4期17卷 633-639页

作者： Robert j Aitken mark A Baker Brett Nixon Priority Research Centre in Reproductive Science Discipline of Biological Sciences and Hunter Medical Research Institute University of Newcastle NSW 2308 Australia.

This chapter explores the possibility that capacitation and apoptosis are linked processes joined by their common dependence on the continued generation of reactive oxygen species （ROS）. According to this model capacitation is initiated in spematozoa following their release into the female reproductive tract as a consequence of intracellular ROS generation, which stimulates intracellular cAMP generation, inhibits tyrosine phosphatase activity and enhances the formation of oxysterols prior to their removal from the sperm surface by albumin. The continued generation of ROS by capacitating populations of spermatozoa eventually overwhelms the limited capacity of these cells to protect themselves from oxidative stress. As a result the over-capacitation of spermatozoa leads to a state of senescence and the activation of a truncated intrinsic apoptotic cascade characterized by enhanced mitochondrial RO$ generation, lipid peroxidation, motility loss, caspase activation and phosphatidylserine externalization. The latter may be particularly important in instructing phagocytic leukocytes that the removal of senescent, moribund spermatozoa should be a silent process unaccompanied by the generation of proinflammatory cytokines. These observations reveal the central role played by redox chemistry in defining the life and death of spermatozoa. A knowledge of these mechanisms may help us to engineer novel solutions to both support and preserve the functionality of these highly specialized cells.

关键词： apoptosis reactive oxygen species sperm capacitation

Assessment of oxide nanoparticle stability in liquid phase transmission electron microscopy

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Nano Research 2019年第9期12卷 2355-2363页

作者： mark j. Meijerink Krijn P. de jong jovana Zecevic Inorganic Chemistry and Catalysis Debye Institute of Nanomaterials ScienceUtrecht UniversityUniversiteitsweg 993584 CG UtrechtThe Netherlands

Studying liquid phase nanoscale dynamic processes of oxide nanoparticles is of considerable interest to a wide variety of *** developed liquid phase transmission electron microscopy(LP-TEM)is a promising technique,but destabilization of oxides by solid-liquid?electron interactions remains an important *** this work we present a methodology to assess LP-TEM oxide stability in an aqueous phase,by subjecti ng several oxides of tech no logical importa nee to a controlled electr on dose in *** show a correlati on based on the Gibbs free en ergy of oxide hydrati on that can be used to assess the stability of oxides and dem on strate the existenee of several remarkably stable oxides,with no observable structural changes after one hour of electron beam irradiation in *** such destabilization phenomena combined with the identification of stable oxides allows for designing LP-TEM experiments free from adverse beam effects and thus in vestigati ons of numerous releva ntnano scale processes in water.

关键词： liquid phase transmission electron microscopy(LP-TEM) transmission electron microscopy electron beam damage metal oxide nano materials oxide stability

Three-dimensional steep wave impact on a vertical cylinder

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journal of Hydrodynamics 2016年第4期28卷 523-533页

作者： Ioannis K.CHATjIGEORGIOU Alexander A.KOROBKIN mark j.COOKER School of Mathematics University of East Anglia School of Naval Architecture and Marine Engineering National Technical University of Athens

In the present study we investigate the 3-D hydrodynamic slamming problem on a vertical cylinder due to the impact of a steep wave that is moving with a steady *** linear theory of the velocity potential is employed by assuming inviscid,incompressible fluid and irrotational *** the problem is set in 3-D space,the employment of the Wagner condition is *** set of equations we pose,is presented as a mixed boundary value problem for Laplace＇s equation in *** from the mixedtype of boundary conditions,the problem is complicated by considering that the region of wetted surface of the cylinder is a set whose boundary depends on the vertical coordinate on the cylinder up to the *** make some simple assumptions at the start but otherwise we proceed *** find closed-form relations for the hydrodynamic variables,namely the time dependent potential,the pressure impulse,the shape of the wave front（from the contact point to beyond the cylinder） and the slamming force.

关键词： cylinder hydrodynamic incompressible steep Wagner employment otherwise coordinate analytically assumptions

Optimizing the oxide support composition in Pr-doped CeO_(2) towards highly active and selective Ni-based CO_(2) methanation catalysts

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journal of Energy Chemistry 2022年第8期31卷 547-561,I0015页

作者： Anastasios I.Tsiotsias Nikolaos D.Charisiou Ayesha AlKhoori Safa Gaber Vlad Stolojan Victor Sebastian Bart van der Linden Atul Bansode Steven j.Hinder mark A.Baker Kyriaki Polychronopoulou Maria A.Goula Laboratory of Alternative Fuels and Environmental Catalysis(LAFEC) Department of Chemical EngineeringUniversity of Western MacedoniaGR-50100Greece Department of Mechanical Engineering Khalifa University of Science and TechnologyAbu DhabiP.O.Box 127788United Arab Emirates Center for Catalysis and Separations Khalifa University of Science and TechnologyAbu DhabiP.O.Box 127788United Arab Emirates Advanced Technology Institute Department of Electrical and Electronic EngineeringUniversity of SurreyGuildford GU24DLUK Department of Chemical Engineering and Environmental Technology Universidad de ZaragozaCampus Río Ebro-Edificio I+D50018 ZaragozaSpain Instituto de Nanociencia y Materiales de Aragón(INMA) Universidad de Zaragoza-CSICc/María de Luna 350018 ZaragozaSpain Networking Research Center on Bioengineering Biomaterials and NanomedicineCIBERBBN28029 MadridSpain Department of Chemical Engineering Delft University of TechnologyVan der Massweg 92629 HZ DelftThe Netherlands The Surface Analysis Laboratory Faculty of Engineering and Physical SciencesUniversity of SurreyGuildford GU24DLUK

In this study,Ni catalysts supported on Pr-doped Ce O_(2) are studied for the CO_(2) methanation reaction and the effect of Pr doping on the physicochemical properties and the catalytic performance is thoroughly *** is shown,that Pr^(3+)ions can substitute Ce^(4+)ones in the support lattice,thereby introducing a high population of oxygen vacancies,which act as active sites for CO_(2) *** doping can also act to reduce the crystallite size of metallic Ni,thus promoting the active metal *** performance evaluation evidences the promoting effect of low Pr loadings(5 at%and 10 at%)towards a higher catalytic activity and lower CO_(2) activation *** the other hand,higher Pr contents negate the positive effects on the catalytic activity by decreasing the oxygen vacancy population,thereby creating a volcano-type trend towards an optimum amount of aliovalent substitution.

关键词： Power-to-gas CO_(2)methanation Ni-based catalyst Pr-doped CeO_(2) Oxygen vacancy Catalytic activity Activation energy

Ultrasound responsive microcapsules for antibacterial nanodrug delivery

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Nano Research 2023年第2期16卷 2738-2748页

作者： jilin Fan Mingjun Xuan Pengkun Zhao mark Loznik junlin Chen Fabian Kiessling Lifei Zheng Andreas Herrmann Wenzhou Institute University of Chinese Academy of SciencesWenzhou 325001China DWI—Leibniz Institute for Interactive Materials Forckenbeckstr.5052074 AachenGermany Institute of Technical and Macromolecular Chemistry RWTH Aachen UniversityWorringerweg 152074 AachenGermany Institute for Experimental Molecular Imaging University Hospital AachenForckenbeckstr.5552074 AachenGermany

The development of ultrasound-responsive microcapsule structures has resulted in several spatiotemporally controlled drug delivery systems for macromolecular cargoes,including proteins,nucleic acids,and even cells for biomedical ***,utilizing microcapsules to transport small molecular cargoes remains a challenge,because the leakage of drugs before ultrasound irradiation might cause side effects such as the undesired toxicity and the decrease of effective drug concentration at the target ***,we present a novel strategy to tackle these shortcomings by employing nanodrugs which refers to nanoparticles coated with small molecule *** showed that the drug leakage was prevented when encapsulating the nanodrug in ***,the fabricated drug delivery system was responsive not only to unfocused high-intensity ultrasound but also to the clinically relevant high-intensity focused ***,as a proof of concept,we showed that the antibacterial activity of the nanodrug@Microcapsules could be activated by applying ultrasound in *** results may provide new insights into the development of ultrasound triggered small molecule drug delivery assisted by metallic nanoparticles.

关键词： microcapsules vancomycin-nanodrug sonication drug release

Impact of extended-infusion piperacillin-tazobactam in a Canadian community hospital

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Infectious Medicine 2023年第1期2卷 31-35页

作者： April j.Chan Gerald Lebovic Michael Wan Yan Chen Elizabeth Leung Bradley j.Langford jenny Seah Linda R.Taggart mark Downing Department of Pharmacy Unity Health TorontoTorontoOntarioCanada University of Toronto TorontoOntarioCanada Division of Infectious Diseases Unity Health TorontoTorontoOntarioCanada Public Health Ontario TorontoOntarioCanada Hotel Dieu Shaver Health and Rehabilitation Centre St.CatharinesOntarioCanada

Background:Studies have demonstrated improved clinical outcomes with extended infusion(EI)piperacillin/tazobactam(TZP)compared to standard infusion(SI).However,there is less evidence on its benefits in noncritically-ill ***-wide EI TZP was implemented at our site on February 21,*** objectives were to compare clinical,safety and economic outcomes between EI and SI ***:A retrospective cohort study of all adult patients who received EI TZP(3.375 g IV q8h infused over 4 hours and SI TZP for≥48 hours during 3 years pre-and postimplementation was *** primary study outcome was 14-day mortality while secondary outcomes included length of hospital stay(LOS),nursing plus pharmacy cost,occurrence of Clostridioides difficile infection,readmission within 30 days and change in Pseudomonas aeruginosa minimum inhibitory concentration(MIC)distribution for *** primary outcome and binary secondary outcomes were analyzed using a logistic regression *** was examined using time to event *** was examined using linear regression ***:Overall,2034 patients received EI TZP and 1364 patients received SI *** TZP was associated with lower odds of mortality(OR 0.76,95%CI 0.63-0.91),lower odds of *** infection(OR 0.59,95%CI 0.41-0.84)and 8%lower cost(estimate 0.92,95%CI 0.87-0.98)compared to SI ***:Hospital-wide implementation of EI TZP was associated with lower odds of 14-day mortality and incidence of *** infection with cost savings at our institution.

关键词： Antimicrobial stewardship Piperacillin/tazobactam Extended-infusion

Role of arthropod communities in bioenergy crop litter decomposition

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Insect Science 2013年第5期20卷 671-678页

作者： Arthur R. Zangerl Saber Miresmailli Paul Nabity allen Lawrance Alan Yanahan Corey A. Mitchell Kristina j. Anderson-Teixeira mark B. David May R. Berenbaum Evan H. DeLucia Department of Entomology Energy Bioscience Institute Department of Plant Biology Institute of Genomic Biology Department of Natural Resources and Environmental Sciences University of Illinois Urbana IL 61801 USA

The extensive land use conversion expected to occur to meet demands for bioenergy feedstock production will likely have widespread impacts on agroecosystem biodiversity and ecosystem services, including carbon sequestration. Although arthropod detritivores are known to contribute to litter decomposition and thus energy flow and nutrient cycling in many plant communities, their importance in bioenergy feedstock communities has not yet been assessed. We undertook an experimental study quantifying rates of litter mass loss and nutrient cycling in the presence and absence of these organisms in three bioenergy feedstock crops—miscanthus （Miscanthus x giganteus）, switchgrass （Panicum virgatum）, and a planted prairie community. Overall arthropod abundance and litter decomposition rates were similar in all three communities. Despite effective reduction of arthropods in experimental plots via insecticide application, litter decomposition rates, inorganic nitrogen leaching, and carbon–nitrogen ratios did not differ significantly between control （with arthropods） and treatment （without arthropods） plots in any of the three community types. Our findings suggest that changes in arthropod faunal composition associated with widespread adoption of bioenergy feedstock crops may not be associated with profoundly altered arthropod-mediated litter decomposition and nutrient release.

关键词： biodiversity bioenergy decomposition detritivore land use change prairie

Overhead shoulder press - In-front of the head or behind the head？

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journal of Sport and Health Science 2015年第3期4卷 250-257页

作者： mark R. McKean Brendan j. Burkett Faculty of Science Health and Education School of Health and Sport Sciences University of the Sunshine Coast Sippy Downs Queensland 4556 A ustralia

背景:肩上举是一种常用练习,两种技术(头前式和头后式)可能会影响关节结构,因此需做客观分析。本研究旨在通过横向比较研究两种肩上举技术对肩部活动度和脊柱姿态的影响。方法:运用角度测量和三维生物力学测试方法研究33名受试者进行坐... 详细信息

背景:肩上举是一种常用练习,两种技术(头前式和头后式)可能会影响关节结构,因此需做客观分析。本研究旨在通过横向比较研究两种肩上举技术对肩部活动度和脊柱姿态的影响。方法:运用角度测量和三维生物力学测试方法研究33名受试者进行坐姿肩上举练习时肩关节的被动和主动活动幅度。结果:头前举在脊柱前凸的姿势下开始,头后举在脊柱后凸的姿势下开始。与头前举相比,头后举开始时的胸部伸展幅度更小。无论何种性别、何种肩上举技术,胸推均呈伸展状,且动作过程中的角度为12°-15°。两种肩上举技术在性别上表现出显著性差异。男性能保持正常的腰椎前凸,而女性则表现为腰椎后凸。结论:除头后式技术时男性肩关节产生外旋外,其余的肩关节动作幅度都在被动动作幅度之内。为避免可能出现的损伤,在头后式肩上举练习前应增加被动动作幅度。女性显现出更大的脊柱活动度,表明加强躯干力量有助于肩上举动作的完成。对具有正常躯干稳定性和理想肩关节动作幅度的受试者来说,无论头前式还是头后式,推举对于肩部和脊柱都最一种较为安全的练习。

关键词：只读存储器指标量化力学测量性别差异肩关节凸位置设计比较活动范围

Heterozygous carriers of galactocerebrosidase mutations that cause Krabbe disease have impaired microglial function and defective repair of myelin damage

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Neural Regeneration Research 2018年第3期13卷 393-401页

作者： Nicole j.Scott-Hewitt Christopher j.Folts mark D.Noble Department of Biomedical Genetics University of Rochester School of Medicine and Dentistry

This review addresses two puzzling findings related to mutations in galactocerebrosidase （GALC） that cause Krabbe disease （KD）, a severe lysosomal storage disorder characterized by extensive myelin damage in children with mutations in both GALC alleles. First, heterozygous carriers of KD-causing mutations, which include the biological parents of children with KD, exhibit increased risk for developing other diseases. Second, variants in the GALC locus increase the risk of developing multiple sclerosis （MS）, another disease characterized by extensive myelin damage. What explains these correlations？ In studies on cuprizone-induced myelin damage in heterozygous （GALC＋/–） mice carrying one copy of a mutation that causes KD-like disease, the extent of damage was similar in GALC＋/– and wild-type （WT） mice. In contrast, GALC＋/- mice had striking defects in repair of cuprizone-induced damage. We further found unexpected microglial defects in myelin debris clearance and in the ability to up-regulate the Trem2 microglial protein critical for debris uptake. These defects were rescued by exposure to a lysosomal re-acidifying drug discovered in our studies on KD, and which provides multiple clinically relevant benefits in the twitcher （GALC＋/–） mouse model of KD. Thus, heterozygous GALC mutations cause effects on biological function that may help to understand the increased disease risk in heterozygous carriers of such mutations and to understand why GALC variations increase the risk of MS. Our findings indicate that while some genetic risk factors may contribute to complex diseases by increasing the risk of tissue damage, others may do so by compromising tissue repair.

关键词： vulnerability locus multiple sclerosis Krabbe disease galactocerebrosidase microglia myelin repair lysosomal storage disorders heterozygous carriers Trem2 demyelination