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World Journal of Orthopedics 2016年第7期7卷 452-457页

作者： Hossein elgafy Nicholas Peters justin e lea Robert M Wetzel Department of Orthopedic Surgery University of Toledo Medical Center

A 64-year-old-female presented with progressive left foot weakness, low back and radicular pain after a left sided S1 transforaminal epidural steroid injection(eSI). Magnetic resonance imaging revealed left side L5-S1 large extradural heterogeneous mass with layering areas suggesting different stages of hematoma formation. Past medical history was significant for peripheral vascular disease and transient ischemic attacks, for which she took aspirin and clopidogrel(antiplatelet agent). These medications were discontinued one week prior to eSI. Although synovial cysts associated with facet arthropathy are common, hemorrhagic cyst is not. To the best of the authors' knowledge, this is the first reported case of symptomatic hemorrhagic lumbar facet synovial cyst following eSI on a patient taking antiplatelet medications.

关键词： Lumbar synovial cyst Hemorrhage Antiplatelet therapy epidural injection

Psychophysics of the hoverfly: categorical or continuous color discrimination?

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Current Zoology 2019年第4期65卷 483-492页

作者： lea Hannah Adrian G. Dyer Jair e. Garcia Alan Dorin Martin Burd School of Biological Sciences Monash University Clayton Victoria 3800 Australia Hawkesbury Institute for the environment Western Sydney University Richmond New South Wales 2753 Australia School of Media and Communication RMIT University Melbourne Victoria 3001 Australia Department of Physiology Monash University Clayton Victoria 3800 Australia Faculty of Information Technology Monash University Clayton Victoria 3800 Australia

There is increasing interest in flies as potentially important pollinators. Flies are known to have a complex visual system, in eluding 4 spectral classes of photoreceptors that con tribute to the perception of color. Our current understanding of how color signals are perceived by flies is based on data for the blowfly Lucilia sp., which after being conditi oned to rewarded mono chromatic light stimuli, showed evidenee of a categorical color visual system. The resulting opponent fly color space has 4 distinct categories, and has been used to interpret how some fly pollinators may perceive flower colors. However, formal proof that flower flies (Syrphidae) only use a simple, categorical color process remains outstanding. In free-flying experiments, we tested the hoverfly eristalis tenax, a Batesian mimic of the honeybee, that receives its nutrition by visiting flowers. Using a range of broadband similar-dissimilar color stimuli previously used to test color perception in pollinating hymenopteran species, we evaluated if there are steep changes in behavioral choices with continuously increasing color differences as might be expected by categorical color processing. Our data revealed that color choices by the hoverfly are mediated by a continuous monotonic function. Thus, these flies did not use a categorical processing, but showed evidenee of a color discrimination function similar to that observed in several bee species. We therefore empirically provide data for the minimum color distanee that can be discriminated by hoverflies in fly color space, enabling an improved un derstandi ng of plant-poll in ator interactions with a non-model insect species.

关键词： chromatic signal color model floral color fly pollination plant-pollinator vision

New Characterizations of the Dual Spaces of Hardy-amalgam Spaces

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Acta Mathematica Sinica,english Series 2022年第3期38卷 519-546页

作者： Zobo Vincent de Paul ABLe justin FeUTO Laboratoire de Mathématiques Fondamentales UFR Mathématiques et InformatiqueUniversitéFélixHouphouët-Boigny Abidjan-Cocody22B.P.582Abidjan 22Côte d’Ivoire Laboratoire de Mathématiques Fondamentales UFR Mathématiques et InformatiqueUniversitéFélixHouphouët-Boigny Abidjan-Cocody22B.P.1194Abidjan 22Côte d’Ivoire

In this paper,carrying on with our study of the Hardy-amalgam spaces H^((q,p)) and H^((q,p))_(loc)(0e give a characterization of their dual spaces whenever 0eover,when 0ese ch... 详细信息

In this paper,carrying on with our study of the Hardy-amalgam spaces H^((q,p)) and H^((q,p))_(loc)(0e give a characterization of their dual spaces whenever 0eover,when 0ese characterizations coincide with those obtained in our earlier papers.

关键词： Amalgam spaces Hardy-amalgam spaces duality Pseudo-differential operators

Highly active and durable Pd-Cu catalysts for oxygen reduction in alkaline exchange membrane fuel cells

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Frontiers in energy 2017年第3期11卷 299-309页

作者： Xiong PeNG Travis J. OMASTA justin M. ROLLeR William e. MUSTAIN Department of Chemical and Biomolecular engineering University of Connecticut 191 Auditorium Drive Storrs CT 06269 USA

A Pd-Cu catalyst, with primary B2-type phase, supported by VulcanXC-7R carbon was synthesized via a solvothermal method. The catalysts were physically and electrochemically characterized by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, trans- mission electron microscopy （TeM） and both cyclic and linear sweep voltammetry using a rotating disk electrode （RDe）. During the RDe testing, the half-wave potential of the Pd-Cu/Vulcan catalyst was 50 mV higher compared to that of commercial Pt/C catalyst for the oxygen reduction reaction （ORR） in alkaline media. The Pd-Cu/Vulcan exhibited a specific activity of 1.27 mA/cm2 and a mass activity of 0.59 A/mgpd at 0.9 V, which were 4 and 3 times greater than that of the commercial Pt/C catalyst, respectively. The Pd-Cu/Vulcan catalyst also showed higher in-situ alkaline exchange membrane fuel cell （AeMFC） performance, with operating power densities of 1100 MW/cm2 operating on H2/O2 and 700 MW/cm2 operating on H2/Air （CO2-free）, which were markedly higher than those of the commercial Pt/C. The Pd-Cu/ Vulcan catalyst also exhibited high stability during a short-term, in-situ AeMFC durability test, with only around 11% performance loss after 30 hours of operation, an improve- ment over most AeMFCs reported in the literature to date.

关键词： alkaline exchange membrane (AeM) fuel cell Pd-Cu oxygen reduction high performance water

Concurrent learning-based Approximate Feedback-Nash equilibrium Solution of N-player Nonzero-sum Differential Games

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Ieee/CAA Journal of Automatica Sinica 2014年第3期1卷 239-247页

作者： Rushikesh Kamalapurkar justin R.Klotz Warren e.Dixon the Department of Mechanical and Aerospace engineering University of Florida

This paper presents a concurrent learning-based actor-critic-identifier architecture to obtain an approximate feedback-Nash equilibrium solution to an infinite horizon Nplayer nonzero-sum differential *** solution is obtained online for a nonlinear control-affine system with uncertain linearly parameterized drift *** is shown that under a condition milder than persistence of excitation(Pe),uniformly ultimately bounded convergence of the developed control policies to the feedback-Nash equilibrium policies can be *** results are presented to demonstrate the performance of the developed technique without an added excitation signal.

关键词： Convergence Function approximation Games learning (artificial intelligence) Stability analysis Trajectory Nonlinear system data driven control dynamic programming optimal adaptive control Converge excitation signal Approximate function approximation Stability analysis differential games Nonlinear systems trajectory Game theory Nash equilibrium dynamic programming adaptive control

Monomer-activated Copolymerization of ethylene Oxide and epichlorohydrin: In Situ Kinetics evidences Tapered Block Copolymer Formation

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Chinese Journal of Polymer Science 2019年第9期37卷 912-918页

作者： Ann-Kathrin Danner Daniel Leibig lea-Marie Vogt Holger Frey Institute of Organic Chemistry Johannes Gutenberg- Universitat Mainz Duesbergweg 10-14 55128 Mainz Germany Graduate School Materials Science in Mainz Staudinger Weg 9 55128 Mainz Germany

The monomer-activated anionic ring-opening copolymerization (AROP) of ethylene oxide (eO) and epichlorohydrin (eCH) using tetraoctylammonium bromide as an initiator and triisobutylaluminum (i-Bu3Al) as an activator was studied. The properties of the copolymers as well as the microstructure have been analyzed in detail via an in situ NMR kinetics study. The statistical copolymers exhibited molecular weights ranging from 2350 g·mol^-1 to 38000 g·mol^-1 (measured by SeC, PeG-standards) and moderate dispersities of 1.27-1.44. The thermal property tests revealed both a glass transition and melting for all copolymers, supporting a block-like nature. Applying in situ NMR kinetic measurements, the reactivity ratios of eO and eCH were determined to be strongly disparate, i.e., reo = 9.2 and reCH = 0.10. This shows that the simple one-pot statistical anionic copolymerization of eO and eCH via the monomer-activated AROP resulted in the formation of strongly tapered, block-like structures. Furthermore, post-polymerization functionalization of the reactive chloromethyl groups by nucleophilic displacement was investigated for the copolymers. Copolymerization of eO and eCH offers a broad platform for further functionalization and therefore the possibility to prepare a variety of multifunctional PeGs.

关键词： epichlorohydrin Polymerization Ring-opening Copolymerization Reactivity ratios epoxide

Disease spectrum and use of cholecystolithotomy in gallstone ileus

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Hepatobiliary & Pancreatic Diseases International 2012年第5期11卷 553-557页

作者： Nicholas e Williams justin S Gundara Sophia Roser Jaswinder S Samra Upper Gastrointestinal Surgical Unit Royal North Shore HospitalUniversity of SydneySt.LeonardsSydneyNSW 2065Australia

BACKGROUND: Gallstone ileus is a heterogeneous and highly morbid condition that suffers from a lack of consensus regarding the timing and approach to management of the biliary tree and associated fistula. MeTHODS: We report three cases that demonstrate the spectrum of gallstone ileus with classical examples of both Barnard’s and Bouveret’s syndromes. Clinical presentation diagnostic imaging, surgical technique and outcome are discussed. ReSULTS: One patient with Barnard’s syndrome presented with recurrent gallstone ileus. To minimize the risks of complex, definitive biliary surgery and avoid further recurrent episodes, a cholecystolithotomy was performed with effect Two cases of Bouveret’s syndrome were successfully managed with enterolithotomy/cholecystectomy and multivisceral resection respectively, thus highlighting the diverse nature of this disease and management options. CONCLUSIONS: Following enterolithotomy, potentially morbid definitive one-stage surgery in typically compromised, elderly patients needs to be weighed against the risk of recurrence and ongoing biliary pathology. We suggest the use of open cholecystolithotomy for the removal of residual gallstones when the patient is not suitable for definitive biliary surgery.

关键词： cholecystectomy biliary tract disease gallstone ileus biliary tract surgery

The ghosts of parasitism past:lingering frontline anti-brood parasite defenses in a former host

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Current Zoology 2021年第6期67卷 573-583页

作者： Matthew.H.J.CHAUMONT Naomi e.LANGMORe justin A.WeLBeRGeN Hawkesbury Institute for the environment Western Sydney University RichmondNSW2753Australia Research School of Biology Australian National UniversityCanberraACT 2600Australia

Coevolutionary arms races between brood parasites and hosts provide tractable systems for understanding antagonistic coevolution in nature;however,little is known about the fate of frontline antiparasite defenses when the host“wins”the coevolutionary arms *** recreating bygone species interactions,using artificial parasitism experiments,lingering defensive behaviors that evolved in the context of parasitism can be understood and may even be used to identify the unknown agent of parasitism *** we present the first study of this type by evaluating lingering“frontline”nest defenses that have evolved to prevent egg laying in a former brood parasite *** Australian reed warbler Acrocephalus australis is currently not parasitized but is known to exhibit fine-tuned egg discrimination—a defensive behavior indicative of a past brood parasite–host arms race and common in closely related parasitized ***,using 3D-printed models of adult brood parasites,we examined whether the Australian reed warbler also exhibits frontline defenses to adult brood parasites,and whether we could use these defenses to identify the warbler’s“ghost of parasitism past.”Our findings provide evidence that the Australian reed warbler readily engages in frontline defenses that are considered adaptive specifically in the context of brood ***,individuals were unable to discriminate between adults of different brood parasite species at their ***,our results demonstrate that despite a relaxation in selection,defenses against brood parasitism can be maintained across multiple stages of the host’s nesting cycle,and further suggest that,in accordance with previous findings,that learning may be important for fine-tuning frontline defense.

关键词： brood parasites coevolutionary arms-race ghosts of parasitism past hosts lingering traits

Unilateral mimicking bilateral BPPV- a forgotten entity? Characteristics of a largecohort of patients, comparison with posterior canal BPPV and clinical implications

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Journal of Otology 2021年第4期16卷 252-257页

作者： lea Pollak Ronit Gilad Tal Michael Neurology and Dizziness Clinic Kupat Cholim Macabi and the Ben GurionUniversity of the NegevBeer ShevaIsrael Neurology Department Kaplan Medical CenterRechovotAffiliated to the HebrewUniversityJerusalemIsrael The Faculty of Health Public Ben Gurion University of the NegevBeerShevaIsrael

Objective: Unilateral mimicking bilateral benign paroxysmal positional vertigo (umb-BPPV) was attributed to inappropriate head positioning during testing of the posterior canal. Despite its inclusion in theDiagnostic criteria for the classification of vestibular disorders of the Barany Society, the clinical characteristics and treatment responsiveness of this BPPV subtype have not been intensively ***: Records of patients with BPPV seen at a single outpatient dizziness clinic during the years 2000e2020 were reviewed. eighty seven patients with umb-BPPV and 86 random patients with posteriorcanal BPPV (p-BPPV) were retrieved. Their demographics and BPPV characteristics were ***: Patients' and BPPV characteristics were similar in umb- and p-BPPV except for the prevalence ofmales in the umb-BPPV group. No differences were found between treatment responsiveness and recurrences in both groups. The recurrence rate of umb-BPPV was not influenced by age, gender, BPPV side,duration of symptoms or treatment responsiveness during the first ***: In accordance with our hypothesis about mixed canalo- and cupulolithiasis as the underlying mechanism of umb-BPPV, patients did not differ in characteristics and treatment responsivenessfrom p-BPPV patients. Recognition of umb-BPPV is important since inappropriate treatment can cause anunnecessary delay in therapy success.

关键词： Benign paroxysmal positional vertigo Canalo-and cupulolithiasis

Method for rapid on-site identification of VOCs

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Journal of environmental Sciences 2009年第7期21卷 1005-1008页

作者： justin D Fair William F Bailey Robert A Felty Amy e Gifford Benjamin Shultes Leslie H Volles Department of Chemistry University of Connecticut Storrs Connecticut 06269-3060 USA. INFICON Inc. 2 Technology Place East Syracuse New York 13057 USA

Rapid on-site identification of volatile organic compounds （VOCs） in ambient air is an important first step in remediation efforts. This study describes modification of a commercially available, portable GC/MS system and development of an analysis protocol for rapid （〈 3 min） sampling and identification of VOCs typically found at contaminated sites at the low ppbv level.

关键词： field analysis gas chromatograph mass spectrometer toxic industrial chemicals thermal desorption