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规范场中单极子的某些研究

物理学进展 1988年第1期 1-28页

作者：陈匡武周尚真 Rutherford Appleton Laboratory Chilton Didcot oxon oxll OQX England mathematical institute oxford university 24-29 st. giles oxford oxl 3 lb Englend

单极是规范场的一个内禀拓扑因素,而且单极的拓扑结构已足决定它的运动规律,这无论在阿贝尔或非阿贝尔场都如是。本文对规范场中单极子的基本概念作一个简单的介绍,并稍为涉及孤子单极,和单极在物理世界的可能存在问题。

关键词：单极子阿贝尔物理世界拓扑结构磁荷磁单极量子化运动规律跃迁振幅 Dirac

衡量河流可持续性的综合指标研究——以黄河为例

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人民黄河 2012年第10期34卷 6-6页

作者： WU Hui-juan(university of oxford,st Edmund hall,Queen’s Lane,oxford,oxfordshire ox1 4AR,United Kingdom) 牛津大学圣埃德蒙堂

1987年,世界环境与发展委员会将可持续发展的理念提上全球议程,并很快得到广泛认可。自此,各国专家学者致力于诠释不同领域可持续发展的内涵,以及开发衡量工具。在河流系统的研究领域中,提出了将河流的健康状况与经济发展和社会效益统... 详细信息

1987年,世界环境与发展委员会将可持续发展的理念提上全球议程,并很快得到广泛认可。自此,各国专家学者致力于诠释不同领域可持续发展的内涵,以及开发衡量工具。在河流系统的研究领域中,提出了将河流的健康状况与经济发展和社会效益统一的河流可持续性理念。本文进一步提出了一个量化河流可持续性的综合方法,并将综合河流可持续发展指数(CRSI)应用于黄河研究,旨在为流域统一管理的多目标决策提供科学证据。方法:提出了一个衡量多维概念的方法,如衡量环境质量(阿特金森等,1997;经济合作与发展组织,2004)。本研究旨在开发一个CRSI,以充分利用其灵活、强大和界面友好的特性。用过程分析方法(PAM)生成具有正式且透明的可持续性指标,因此用该方法来构建一个CRSI。案例研究:黄河是中国第二长河,穿越华北平原,全长5 464 km,流域面积为79.5万km2。作为中国北方的主要水源,黄河为全国12%的人口和约15%的总灌溉面积提供水源。河流可持续理念需要一个广泛的、清晰的定义。这进一步表明它需要进行定量衡量。讨论了如何通过生成对应于环境、社会和经济指标来构建一个CRSI。

关键词：综合指标黄河可持续发展

Drought and Heat Triggers Sudden and Severe Dieback in a Dominant Mediterranean-Type Woodland Species

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Open Journal of Forestry 2012年第4期2卷 183-186页

作者： George Matusick Katinka X. Ruthrof giles st. J. Hardy Centre of Excellence for Climate Change Woodland and Forest Health Murdoch University Perth Australia

Ecosystems in Mediterranean climate regions are projected to undergo considerable changes as a result of shifting climate, including from extreme drought and heat events. A severe and sudden dieback event, occurring in regionally significant Eucalyptus gomphocephala woodland in Western Australia, coincided with extreme drought and heat conditions in early 2011. Using a combination of remote sensing and field- based approaches, we characterized the extent and severity of canopy dieback following the event, as well as highlighted potential predisposing site factors. An estimated 500 ha of woodland was severely affected between February and March 2011. Tree foliage rapidly discolored and died over this period. In the af-fected portion of the woodland, approximately 90% of trees greater than 20 cm DBH were impacted, while in the adjacent unaffected woodland 6% showed signs of damage. Tree density in the unaffected area had approximately 4.5 times more trees than the affected woodland. Precipitation drainage patterns are thought to explain the difference between affected and unaffected woodland. Dropping groundwater levels, a relatively shallow soil profile, and extreme drought and heat in 2010-2011 are thought to predispose water-shedding sites to drought-triggered canopy dieback during extended periods of dryness. Tracking forest health changes in response to severe disturbance is an important key to deciphering past and future vegetation change.

关键词： Eucalyptus Gomphocephala Forest Western Australia Die-Off Climate Change

Facilitating Regeneration of an Iconic Canopy Species with Specific Niche Requirements

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Open Journal of Forestry 2015年第4期5卷 402-408页

作者： Katinka X. Ruthrof George Matusick Leonie E. Valentine giles E. st. J. Hardy School of Veterinary and Life Sciences Murdoch University Perth Australia The Nature Conservancy Georgia Chapter Chattahoochee Fall Line Conservation Office Fort Benning GA USA NERP Environmental Decisions Hub School of Plant Biology University of Western Australia Perth Australia

Natural regeneration is a critical component of forest ecosystems sustainability. Local extinction can occur without adequate regenerationor seedling recruitment prior to adult senescence. The urban and peri-urban environment is particularly challenging for recruitment. For example, although many forest species have specific requirements involving fire events, few opportunities associated with fire exist in contemporary urban and peri-urban environments. For our study species, Eucalyptus gomphocephala, en masse recruitment can occur in ashbeds following a hot fire. However, this may not occur following low-intensity, fuel reduction burns that are prescribed for many E. gomphocephala woodlands and forests. Nevertheless, ashbeds could be created by constructing and burning coarse woody debris (CWD) piles. In a series of collaborative case studies involving community groups, NGOs and Local and state Government agencies, we investigated whether seedling recruitment could be facilitated through broadcast seeding after: a) creating CWD piles prior to a low intensity, prescribed burn;b) naturally-occurring ashbeds following a hot summer wildfire;and c) creating CWD piles and then burning the piles only. We found that regeneration of this post-fire, canopy gap regenerator can be facilitated by broadcast seeding naturally occurring or created ashbeds. However, it seems that protection from seed harvesters and herbivores is vital. These case studies provide tools that can be used to preserve the natural demographics in populations with specific regeneration requirements in a range of environments by leveraging natural recruitment processes and community involvement. Importantly, it is the conservation of these urban and peri-urban ecosystems that will be vital in maintaining connection between people and the environment into the future.

关键词： Ashbed Fire Eucalyptus gomphocephala Community Involvement Restoration

Reconstruction of hollow areas in density profiles from frequency swept reflectometry

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Plasma Science and Technology 2020年第6期22卷 32-40页

作者： Rennan B MORALES stéphane HEURAUX Roland SABOT Sébastien HACQUIN Frédéric CLAIRET the Tore Supra Team United Kingdom Atomic Energy Authority Culham Centre for Fusion EnergyCulham Science CentreAbingdonOxonOX143DBUnited Kingdom IJL UMR CNRSUniversity of LorraineBP50840NancyF-54011France institute of Physics University of Sao PauloSao Paulo 05315-970Brazil IRFM CEACadaracheF-13108 Saint-Paul-lez-DuranceFrance EUROfusion Programme Management Unit Culham Science CentreCulham OX143DBUnited Kingdom

The standard density profile reconstruction techniques are based on the WKB approximation of the probing wave’s phase,making them unable to properly reconstruct blind areas in the cut-off frequency *** reconstruction suffers a significant immediate error that is not rapidly *** is demonstrated that even though no reflections occur inside the hollow region causing the blind area,the higher probing frequencies that propagate through it carry information that can be used to estimate its *** usually ignored full-wave effects were investigated with the use of full-wave simulations in 1 D,with special attention paid to the frequency band where they are dominant.A database of perturbation signals was simulated onfive-dimensions of parameters and an application of the database inversion was demonstrated for a magnetic island in a Tore Supra *** new adapted reconstruction scheme improved the description of the density profile inside the hollow region and also along 10 cm after it.

关键词： FM-CW reflectometry profile reconstruction reflectometry density profile hollow profile blind area

Minimally invasive knee arthroplasty: An overview

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World Journal of Orthopedics 2015年第10期6卷 804-811页

作者： Alfred J Tria giles R Scuderi Department of Orthopaedic Surgery RutgersRobert Wood Johnson Medical Schoolthe Orthopaedic Center of New Jersey Department of Orthopaedic Surgery St.Peter’s University Hospital Orthopedic Service Line Northshore LIJ Health System Adult Knee Reconstruction Lenox Hill Hospital

Minimally invasive surgery(MIS) for arthroplasty of the knee began with surgery for unicondylar knee arthroplasty(ukA).Partial knee replacements were designed in the 1970 s and were amenable to a more limited *** the 1990 s Repicci popularized the MIS for *** began to apply his concepts to total knee *** MIS surgical techniques were developed: quadriceps sparing,mini-mid vastus,mini-subvastus,and minimedial *** quadriceps sparing technique is the most limited one and is also the most ***,it is the least invasive and allows rapid *** mini-midvastus is the most common technique because it affords slightly better exposure and can be *** mini-subvastus technique entirely avoids incising the quadriceps extensor mechanism but is time consuming and difficult in the obese and in the muscular male *** mini-parapatellar technique is most familiar to surgeons and represents a good starting point for surgeons who are learning the *** surgeries are easier with smaller instruments but can be performed with standard *** techniques are accurate and do lead to a more rapid recovery,with less pain,less blood loss,and greater motion if they are appropriately performed.

关键词： Knee Arthroplasty Minimally invasive surgery Replacement Surgery

Broadband diffuse optical spectroscopy of two-layered scattering media containing oxyhemoglobin,deoxyhemoglobin,water,and lipids

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Journal of Innovative Optical Health Sciences 2022年第3期15卷 92-106页

作者： giles Blaney Martina Bottoni Angelo Sassaroli Cristianne Fernandez Sergio Fantini Department of Biomedical Engineering Tufts University 4 Colby StMedfordMA 02155USA Department of Biomedical Engineering Politecnico di Torino 24 Corso Duca degli AbruzziTorinoTO 10129Italy

We investigated the relationship between chromophore concentrations in two-layered scattering media and the apparent chromophore concentrations measured with broadband optical spectroscopy in conjunction with commonly used homogeneous medium inverse *** used diffusion theory to generate optical data from a two-layered distribution of relevant tissue absorbers,namely,oxyhemoglobin,deoxyhemoglobin,water,and lipids,with a top-layer thickness in the range 1–15 *** generated data consisted of broadband continuous-wave(CW)diffuse reflectance in the wavelength range 650–1024 nm,and frequency-domain(FD)diffuse reflectance at 690 and 830 nm;two source-detector distances of 25 and 35mm were used to simulate a dual-slope *** data were inverted using diffusion theory for a semi-infinite homogeneous medium to generate reduced scattering coeffcients at 690 and 830nm(from FD data)and effective absorption spectra in the range 650–1024nm(from CW data).The absorption spectra were then converted into effective total concentration and oxygen saturation of hemoglobin,as well as water and lipid *** absolute values,it was found that the effective hemoglobin parameters are typically representative of the bottom layer,whereas water and lipid represent some average of the respective concentrations in the two *** concentration changes,lipid showed a significant cross-talk with other absorber concentrations,thus indicating that lipid dynamics obtained in these conditions may not be *** systematic simulations of broadband spectroscopy of two-layered media provide guidance on how to interpret effective optical properties measured with similar instrumental setups under the assumption of medium homogeneity.

关键词： Broadband spectroscopy two-layer medium heterogeneous forward model homo-geneous inverse model partial-volume effect

The effect of electroacupuncture on expression of orexin and its receptors in the brain of chronic obstructive pulmonary disease rats

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The effect of electroacupuncture on expression of orexin and...

The next detectors for gravitational wave astronomy

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Zi-Bing LIU~(1,2),Wen-Ye GENG~1,Na-Na SONG~1,Li LI~1,Yin-Xiang CAO~1,Da-Nian ZHU~1,Lin-Lin SHEN~(1,*) 1Department of Physiology and Pathophysiology,Shanghai Medical College,Fudan university,Shanghai 200032, China 2 Anhui Provincial Key Lab of Acu-moxibustion Theoretical Foundation and Techniques,Anhui College of Traditional Chinese Medicine,Hefei 230038,China

＜正＞Objective To investigate the relationship between acupuncture effects on improving pulmonary ventilatory function of chronic obstructive pulmonary disease（COPD）and hypothalamic neuropeptide ***（1） Sprague-Dawley rats were used to establish the COPD model by exposed to cigarette smoke（1h twice daily）for 12 weeks.（2）Model rats were electro-acupunctured on bilateral acupoints Feishu（BL13）and Zusanli（st36）for 30 minutes a day for two weeks.（3）Hypothalamic and medullary orexinA levels were detected by radioimmunoassay, the orexin receptors’ mRNA and positive immunoreactivity were observed by fluorescence realtime quantitative PCR and immunohistochemistry ***（1）The decrease of airway resistance and the increase of lung dynamic compliance in COPD model rats were occured after acupuncture treatment（P＜0.05）.（2）The orexinA level in hypothalamus and medulla was very higher in model group than that in normal group（P＜0.01,P＜0.001）,but not significantly decreased in electro-acupuncture group.（3）mRNA and immune response positive expression of ox1R in ventrolateral medulla was significantly higher in the model group than those in the normal group（P＜0.01）,but mRNA and immune response positive expression of ox2R decreased significantly in the electro-acupuncture group compared with the model（P＜0.01）.Conclusion The effect of acupuncture for improving the pulmonary ventilatory function in COPD rats may be relevant to the down-regulation of neuropeptide orexin receptors’ expression in medulla oblongata.

关键词： electro-acupuncture Feishu Zusanli chronic obstructive pulmonary disease orexin

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Science China(Physics,Mechanics & Astronomy) 2015年第12期58卷 91-124页

作者： BLAIR David JU Li ZHAO ChunNong WEN LinQing MIAO HaiXing CAI RongGen GAO JiangRui LIN XueChun LIU Dong WU Ling-An ZHU ZongHong HAMMOND giles PAIK Ho Jung FAFONE Viviana ROCCHI Alessio BLAIR Carl MA YiQiu QIN JiaYi PAGE Michael School of Physics The University of Western Australia School of Physics and Astronomy University of Birmingham state Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences The School of Physics & Electronic Engineering Shanxi University Laboratory of All-Solid-state Light Sources Institute of Semiconductors Chinese Academy of Science state Key Laboratroy of Modern Optical Instrumentation Department of Optical Engineering Zhejiang University Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Gravitational Wave and Cosmology Laboratory Department of Astronomy Beijing Normal University School of Physics and Astronomy SUPA University of Glasgow Department of Physics University of Maryland College Park university of Rome Tor Vergata INFN Roma Tor Vergata

This paper focuses on the next detectors for gravitational wave astronomy which will be required after the current ground based detectors have completed their initial observations, and probably achieved the first direct detection of gravitational waves. The next detectors will need to have greater sensitivity, while also enabling the world array of detectors to have improved angular resolution to allow localisation of signal sources. Sect. 1 of this paper begins by reviewing proposals for the next ground based detectors,and presents an analysis of the sensitivity of an 8 km armlength detector, which is proposed as a safe and cost-effective means to attain a 4-fold improvement in sensitivity. The scientific benefits of creating a pair of such detectors in China and Australia is emphasised. Sect. 2 of this paper discusses the high performance suspension systems for test masses that will be an essential component for future detectors, while sect. 3 discusses solutions to the problem of Newtonian noise which arise from fluctuations in gravity gradient forces acting on test masses. Such gravitational perturbations cannot be shielded, and set limits to low frequency sensitivity unless measured and suppressed. Sects. 4 and 5 address critical operational technologies that will be ongoing issues in future detectors. Sect. 4 addresses the design of thermal compensation systems needed in all high optical power interferometers operating at room temperature. Parametric instability control is addressed in sect. 5. Only recently proven to occur in Advanced LIGO, parametric instability phenomenon brings both risks and opportunities for future detectors. The path to future enhancements of detectors will come from quantum measurement technologies. Sect. 6 focuses on the use of optomechanical devices for obtaining enhanced sensitivity, while sect. 7 reviews a range of quantum measurement options.

关键词： future gravitational wave detectors opto-mechanics quantum limit