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exploiting AML algorithm for multiple acoustic source 2D and 3D DOA estimations

中国化学会第十三届全国分析化学年会

作者： Jing Hu ralph e.sturgeon Kenny Nadeau Xiandeng Hou Chengbin Zheng Lu Yang Analytical & Testing Center Sichuan University National Research Council Canada Key laboratory of Green Chemistry and Technology and MOE College of Chemistry Sichuan University

A novel,reliable,and sensitive approach for the determination of chlorine by sector field inductively coupled plasma mass spectrometry (SF-ICPMS) using photochemical vapor generation for sample introduction is *** chloride is generated from different chlorine species in a flow through photochemical reactor using a 1%solution of acetic acid containing 7.5μg g of *** volatile product is directed by an argon carrier gas to a gas-liquid separator and introduced into the instrument.A sample flow rate at 1.7 mL min and a 45 s irradiation time provided a 74-fold enhancement in sensitivity compared to conventional nebulization.A blank-limited detection limit of 0.5 ng g for chloride,suitable for quantitation at trace levels,was *** proposed method was validated by analysis of two certified reference materials,NIST SRM 1568b rice flour and SRM 1571 orchard leaves,with satisfactory results,as well as three varieties of bottled water,achieving spike recoveries between 101%and 105%.

关键词： Cu(Ⅱ) photochemical vapor generation chloride ICP-MS

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控制理论与应用（英文版） 2011年第1期9卷 34-43页

作者： Juo-Yu Lee ralph e. HUDSON Kung YAO electrical engineering Department University of CaliforniaLos AngelesCalifornia 90095-1594U.S.A.

The approximate maximum likelihood (AML) algorithm shows promises for joint estimations of acoustic source spectrum and direction-of-arrival (DOA). For the multisource case, the AML algorithm remains feasible as one considers an alternating projection procedure based on sequential iterative search on single source parameters. In order to perform multisource beamforming operations, earlier, we used a two-dimensional (2D) sensor array with 2D AML to obtain the DOA estimations for sources in the far field of the array. Now, the 3D AML algorithm enables a 3D sensor array to collect acoustic data for estimation of DOA represented in azimuth and elevation angles. In this paper, we consider two acoustic sources being simultaneously active and derive Crame′r-Rao bound (CRB) on DOA estimation given by a 3D array. Also, we compare the two-source DOA estimation results of 2D AML and 3D AML, respectively. To construct reasonable constraints on sensor topology, we adopt the concept of isotropic array and decouple the interplay between azimuth and elevation angle variations. The 3D AML algorithm exhibits superior spatial separation over its 2D counterpart for multiple sources located at different azimuth and elevation angles. Although the 3D AML algorithm requires more demanding computational complexity, we have developed a number of efficiency enhancements to reduce the loading for the grid search.

关键词： Approximate maximum likelihood Direction-of-arrival Alternating projection procedure

Characterizing drought in California:new drought indices and scenario-testing in support of resource management

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ecological Processes 2018年第1期7卷 1-13页

作者： Lorraine e.Flint Alan L.Flint John Mendoza Julie Kalansky F.M.ralph U.S.Geological Survey 6000 J.StSacramentoCA 95819USA Sonoma County Water Agency 404 Aviation Dr.Santa RosaCA 95403USA Scripps Institution of Oceanography 9500 Gilman Dr.La JollaCA 92093USA

Introduction:California’s recent drought(2012–2016)has implications throughout the state for natural resource management and adaptation planning and has generated many discussions about drought characterization and *** study characterizes drought conditions with two indices describing deficits in natural water supply and increases in landscape stress developed on the basis of water balance modeling,at a fine spatial scale to assess the variation in conditions across the entire state,and provides an in-depth evaluation for the Russian River basin in northern California to address local resource management by developing extreme drought scenarios for consideration in planning and ***:We employed the USGS Basin Characterization Model to characterize drought on the basis of water supply(a measure of recharge plus runoff)and landscape stress(climatic water deficit).These were applied to the state and to the Russian River basin where antecedent soil moisture conditions were evaluated and extreme drought scenarios were developed and run through a water management and reservoir operations model to further explore impacts on water ***:Drought indices indicated that as of the end of water year 2016 when reservoirs were full,additional water supply and landscape replenishment of up to three average years of precipitation in some locations was needed to return to normal *** soil conditions in the Russian River were determined to contribute to very different water supply results for different years and were necessary to understand to anticipate proper watershed response to *** drought scenarios manifested very different kinds of drought and recovery and characterization helps to guide the management response to ***:These scenarios and indices illustrate how droughts differ with regard to water supply and landscape stress and how long warm droughts recover much more slowly than short very dry dro

关键词： California drought Russian River Water supply Basin Characterization Model

Management of residual penile curvature after penile prosthesis placement

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Asian Journal of Andrology 2021年第2期23卷 129-134页

作者： Denis V Krakhotkin David J ralph Gideon A Blecher Volodymyr A Chernylovskyi Francesco Greco evgeny e Bakurov Ruslan A Bugaev Central District Hospital Outpatient DepartmentKamenolomniRostov Region 346480Russia University College London St Peter’s Andrology Centre and University College London Hospitals London W1G 6BJUnited Kingdom Monash University Department of SurgeryMelbourne 3168Australia The Alfred Hospital Department of UrologyMelbourne 3004Australia Department of Urology 1 City Clinical Hospital No.4Dnipro 49102Ukraine Department of Urology Humanitas GavazzeniBergamo 24125Italy Department of Surgery No.1 Rostov Regional Hospital ROKB 1Rostov-on-Don 344015Russia

Residual penile curvature is a common situation following the implantation of a penile prosthesis in patients with Peyronie’s ***,there is a variety of options for the correction of residual curvature,including penile modeling,plication techniques,as well as tunical incision/excision with or without grafting.A literature search of PubMed and Medline databases was conducted from 1964 until 2020,using search terms for all articles in the english *** this article,we provide a review of the techniques and the outcomes,according to the published literature.

关键词： grafting modeling penile curvature penile implant penile prosthesis Peyronie’s disease tunical plication

Static Scene Illumination estimation from Videos with Applications

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Journal of Computer Science & Technology 2017年第3期32卷 430-442页

作者： Bin Liu Nun Xu ralph R. Martin Department of Computer Science and Technology Tsinghua University Beijing 100084 China School of Computer Science and Informatics Cardiff University Cardiff CF243AA U.K.

We present a system that automatically recovers scene geometry and illumination from a video, providing a basis for various applications. Previous image based illumination estimation methods require either user interaction or external information in the form of a database. We adopt structure-from-motion and multi-view stereo for initial scene reconstruction, and then estimate an environment map represented by spherical harmonics （as these perform better than other bases）. We also demonstrate several video editing applications that exploit the recovered geometry and illumination, including object insertion （e.g., for augmented reality）, shadow detection, and video relighting.

关键词： video processing augmented reality illumination recovery

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诱导烟草早花的PVX-FT系统的建立

中国烟草学报 2013年第6期19卷 102-105页

作者：高玉龙肖炳光 ralph e Dewey 云南省烟草农业科学研究院北卡州立大学Raleigh nc276957620

FT(Flowering locus T)基因是控制植物开花的关键基因,而PVX(Potato virus X)载体能够使外源基因在植物体内高水平瞬时表达。本文构建了拟南芥FT基因PVX病毒瞬时表达载体,通过农杆菌渗滤感染不同类型烟草品种,使拟南芥FT基因在烟草中瞬... 详细信息

FT(Flowering locus T)基因是控制植物开花的关键基因,而PVX(Potato virus X)载体能够使外源基因在植物体内高水平瞬时表达。本文构建了拟南芥FT基因PVX病毒瞬时表达载体,通过农杆菌渗滤感染不同类型烟草品种,使拟南芥FT基因在烟草中瞬时表达。结果表明,该系统能够诱导烤烟品种K326、云烟87和红花大金元,香料烟品种TeVB及白肋烟品种TN90早花,应用于烟草育种,可缩短育种进程。

关键词：烟草早花马羚素X病毒载体 FT基因

Single-molecule DNA sequencing using two-dimensionalTi2C(OH)2 MXene nanopores: A first-principles investigation

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Nano Research 2022年第11期15卷 9843-9849页

作者： Jariyanee Prasongkit Sirichok Jungthawan Rodrigo G.Amorim ralph H.Scheicher Division of Physics Faculty of ScienceNakhon Phanom UniversityNakhon Phanom 48000Thailand School of Physics Institute of ScienceSuranaree University of Technology111 University AveNakhon Ratchasima 30000Thailand Center of excellence in Advanced Functional Materials Suranaree University of TechnologyNakhon Ratchasima 30000Thailand Thailand Center of excellence in Physics Ministry of Higher EducationScienceResearch and Innovation328 Si Ayutthaya RoadBangkok 10400Thailand Departamento de Física ICExUniversidade Federal Fluminense-UFFVolta Redonda/RJ 27213-145Brazil Division of Materials Theory Department of Physics and AstronomyUppsala UniversityUppsala SE-75120Sweden

Nanopore-based devices have provided exciting opportunities to develop affordable label-free DNA sequencing *** a decade ago,graphene has been proposed as a two-dimensional(2D)nanopore membrane in order to achieve single-base ***,it was experimentally revealed that clogging of the graphene nanopore can occur due to the hydrophobic nature of graphene,thus hindering the translocation of *** overcome this problem,the exploration of alternative 2D materials has gained considerable interest over the last *** we show that a Ti_(2)C-based MXene nanopore functionalized by hydroxyl groups(–OH)exhibits transverse conductance properties that allow for the distinction between all four naturally occurring DNA *** have used a combination of density functional theory and non-equilibrium Green’s function method to sample over multiple orientations of the nucleotides in the nanopore,as generated from molecular dynamics *** conductance variation resulting from sweeping an applied gate voltage demonstrates that the Ti_(2)C-based MXene nanopore possesses high potential to rapidly and reliably sequence *** findings open the door to further theoretical and experimental explorations of MXene nanopores as a promising 2D material for nanopore-based DNA sensing.

关键词： nanopore DNA sequencing MXenes first-principles quantum transport

endoscopic debridement for non-insertional Achilles tendinopathy with and without platelet-rich plasma

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Journal of Sport and Health Science 2023年第2期12卷 275-280页

作者： Hajo Thermann ralph Fischer Nikolaos Gougoulias Lucio Cipollaro Nicola Maffulli HKF-International Center for Hip Foot and Knee SurgeryBismarckstrae 9-1569115 HeidelbergGermany Footsurgery Clinic 54631 ThessalonikiGreece Department of Musculoskeletal Disorders Faculty of Medicine and SurgeryUniversity of SalernoSalerno 89100Italy Department of Medicine Surgery and DentistryUniversity of SalernoVia S.Allende84081 Baronissi(SA)Italy Centre for Sports and exercise Medicine Barts and The London School of Medicine and DentistryMile End Hospital275 Bancroft RoadLondon E14DGQueen Mary University of LondonLondonUK School of Pharmacy and Bioengineering Keele University Faculty of MedicineThornburrow DriveStoke on TrentST47QBUK

Background:When non-operative management fails to improve symptoms in patients with non-insertional Achilles tendinopathy,surgery may be *** open and endoscopic techniques have been proposed,and platelet-rich plasma(PRP)injections have been proposed as an adjunct to aid tendon ***:Thirty-six patients with mid-portion Achilles tendinopathy were randomized to undergo endoscopic debridement alone(n=19)or in combination with intraoperative PRP application(n=17).Clinical outcome measures included the Visual Analogue Scale for pain,function,and satisfaction and the Victorian Institute of Sports Assessment-Achilles(VISA-A)*** were followed-up at 6 weeks,3months,6 months,and 12 months after *** MRI examination at 3 and 12 months was used to assess signal alterations within the ***:Both groups showed significant clinical improvement(per surgery,with no difference between the 2 *** diameter increased at 3 months and decreased at 12 *** tendinopathy area increased at 3 months and decreased at 12 months below baseline level in both *** was no significant difference between the groups regarding the MRI *** thickening and MRIdetected signal alteration persisted after surgery,with no association between imaging and clinical *** minor complications were reported:2 in the PRP group and 3 in the control ***:endoscopic debridement of the Achilles tendon improved clinical outcomes in patients with mid-portion *** addition of PRP did not improve outcomes compared to debridement *** parameters showed no association with clinical outcomes.

关键词： Achilles tendon endoscopic Non-insertional PRP Tendinopathy

enhanced oil recovery of low salinity water flooding in sandstone and the role of clay

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Petroleum exploration and Development 2018年第5期45卷 927-931页

作者： Al-SAeDI Hasan N FLORI ralph e Missouri University of Science and Technology

Sandstone core and free-clay sandstone core were prepared in chromatography columns, and core flooding experiments were performed to determine the eOR mechanisms of low salinity（LS） water flooding and analyze the effect of clay on recovery factor. First, brine with a high salinity（HS） of 100 000 mg/L was injected to simulate formation water. Then, LS water of 1 000 mg/L was then injected at different temperatures. Concentrations of Ca;and CH;COO;and pH of the fluid flowing out of the chromatography column were recorded. The results showed that during flooding the free-clay core with LS water, the carboxylic acid detached from the sand, as great as that of the clay-containing cores. It showed a noteworthy desorption of Ca;from the free-clay core surface, which indicated that LS water flooding resulted in a high recovery in sandstone without clay. Compared with HS water flooding, in the LS water flooding, the p H of produced fluid increased significantly; also, as the temperature increased, the pH and Ca;concentration of the produced fluid decreased; and the hydrophilic property of the sandstone was stronger. The results of oil recovery tests using the same columns were in line with the chemical analyses. The oil recovery from the free-clay columns was as great as from the column clay-containing column. The results of wettability measurements supported our theory.

关键词： sandstone reservoir low salinity water flooding enhanced oil recovery water-rock reaction wettability alteration clay

Nanometer ultrastructural brain damage following low intensity primary blast wave exposure

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Neural Regeneration Research 2018年第9期13卷 1516-1519页

作者： Hailong Song Landry M. Konan Jiankun Cui Catherine e. Johnson Graham K. Hubler ralph G. DePalma Zezong Gu Department of Pathology & Anatomical Sciences University of Missouri School of Medicine Columbia MO USA Department of Mining and Nuclear engineering Missouri University of Science and Technology Rolla MO USA Office of Research and Development Department of Veterans Affairs Washington DC USA Truman VA Hospital Research Service Columbia MO USA

Blast-induced mild traumatic brain injury（m TBI） is of particular concern among military personnel due to exposure to blast energy during military training and *** impact of primary low-intensity blast mediated pathophysiology upon later neurobehavioral disorders has been *** a military preclinical blast model to simulate the pathophysiology of human blast injury is an important first *** article provides an overview of primary blast effects and perspectives of our recent studies demonstrating ultrastructural changes in the brain and behavioral disorders resulting from open-field blast exposures up to 46.6 k Pa using a murine *** model is scalable and permits exposure to varying magnitudes of primary blast injuries by placing animals at different distances from the blast center or by changing the amount of C4 *** here review the implications and future applications and directions of using this animal model to uncover the underlying mechanisms related to primary blast ***,these studies offer the prospect of enhanced understanding of the pathogenesis of primary low-intensity blast-induced TBI and insights for prevention,diagnosis and treatment of blast induced TBI,particularly m TBI/concussion related to current combat exposures.

关键词： mild traumatic brain injury openfield blast primary blast wave blast physics animal model altrastructural abnormalities behavior