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Greenhouse gases fluxes and soil thermal properties in a pasture in central Missouri

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Journal of Environmental Sciences 2010年第7期22卷 1029-1039页

作者： Nsalambi Vakanda Nkongolo shane Johnson Kent Schmidt Frieda Eivazi Department of Agriculture and Environmental Sciences College of Agriculture and Natural Science Lincoln University Harvard Forest Faculty of Arts and Sciences Harvard University

Fluctuations of greenhouse gases emissions and soil properties occur at short spatial and temporal scales, however, results are often reported for larger scales studies. We monitored CO2, CH4, and N2O fluxes and soil temperature （T）, thermal conductivity （K）, resistivity （R） and thermal diffusivity （D） from 2004 to 2006 in a pasture. Soil air samples for determination of CO2, CH4 and N2O concentrations were collected from static and vented chambers and analyzed within two hours of collection with a gas chromatograph. T, K, R and D were measured in-situ using a KD2 probe. Soil samples were also taken for measurements of soil chemical and physical properties. The pasture acted as a sink in 2004, a source in 2005 and again a sink of CH4 in 2006. CO2 and CH4 were highest, but N2O as well as T, K and D were lowest in 2004. Only K was correlated with C02 in 2004 while T correlated with both N2O （r = 0.76, p = 0.0001） and CO2 （r = 0.88, p = 0.0001） in 2005. In 2006, all gases fluxes were significantly correlated with T, K and R when the data for the entire year were considered. However, an in-depth examination of the data revealed the existence of month-to-month shifts, lack of correlation and differing spatial structures. These results stress the need for further studies on the relationship between soil properties and gases fluxes. K and R offer a promise as potential controlling factors for greenhouse gases fluxes in this pasture.

关键词： greenhouse gases soil thermal properties fluxes

Behavior and physiology of mechanoreception: separating signal and noise

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Integrative Zoology 2009年第1期4卷 3-12页

作者： John C.MONTGOMERY shane WINDSOR Daniel BASSETT Leigh Marine Laboratory University of AucklandAucklandNew Zealand

The mechanosensory lateral line is found in all aquatic fish and *** provides a highly sensitive and versatile hydrodynamic sense that is used in a wide range of *** stimuli of biological interest originate from both abiotic and biotic sources,and include water currents,turbulence and the water disturbances caused by other animals,such as prey,predators and ***,the detection of biologically important stimuli often has to occur against a background of noise generated by water movement,or movement of the fish *** such,separating signal and noise is“of the essence”in understanding the behavior and physiology of *** we discuss general issues of signal and noise in the lateral-line system and the behavioral and physiological strategies that are used by fish to enhance signal detection in a noisy *** order for signal and noise to be separated,they need to differ,and we will consider those differences under the headings of:frequency and temporal pattern;intensity discrimination;spatial separation;and mechanisms for the reduction of self-generated *** systematically cover the issues of signal and noise in lateral-line systems,but emphasize recent work on self-generated noise,and signal and noise issues related to prey search strategies and collision avoidance.

关键词： behavior lateral line mechanoreception noise physiology signal.

Homogenization Theory for a Replenishing Passive Scalar Field

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Chinese Annals of Mathematics,Series B 2009年第5期30卷 631-644页

作者： Peter R. KRAMER shane R. KEATING Department of Mathematical Sciences Rensselaer Polytechnic Institute Center for Atmosphere-Ocean Science Courant Institute of Mathematical SciencesNew York University

Homogenization theory provides a rigorous framework for calculating the effective diffusivity of a decaying passive scalar field in a turbulent or complex *** authors extend this framework to the case where the passive scalar fluctuations are continuously replenished by a source (and/or sink).The basic structure of the homogenized equations carries over,but in some cases the homogenized source can involve a non-trivial coupling of the velocity field and the *** authors derive expressions for the homogenized source term for various multiscale source structures and interpret them physically.

关键词： Homogenization Turbulent transport Source Pumping

债务危机迫在眉睫国际开发协会增资创新高是关键

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财经界 2024年第7期 47-47页

作者： shane Romig

低收入国家面临全面债务危机，使得国际开发协会第21轮（简称IDA21）增资力争实现史上最大规模成为当务之急。《2023年国际债务报告》强调指出，债务偿还额不断膨胀，挤占了本应用于发展优先重点的稀缺资源。强大的国际开发协会（简称ID...

低收入国家面临全面债务危机，使得国际开发协会第21轮（简称IDA21）增资力争实现史上最大规模成为当务之急。《2023年国际债务报告》强调指出，债务偿还额不断膨胀，挤占了本应用于发展优先重点的稀缺资源。强大的国际开发协会（简称IDA，向世界上最贫困国家提供无息或低息贷款和赠款的基金），是许多贫困国家投资于人力资本和环境、防止来之不易的发展成果得而复失的基本条件。世界银行首席统计师、发展数据局局长傅海珊指出：“最贫困的国家需要帮助，而且现在就需要。每个季度利率居高不下，都会导致更多的低收入和中等收入国家陷入困境，面临在偿还公共债务还是投资发展公共卫生、教育和基础设施之间的艰难抉择。我们需要加倍努力来为国际开发协会提供减贫和推动绿色转型所需的资源。”

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An overview of research efforts to understand the effects of underwater sound on cetaceans

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Water Biology and Security 2023年第2期2卷 1-12页

作者： shane Guan Tiffini Brookens Bureau of Ocean Energy Management Environmental Studies ProgramUSA Marine Mammal Commission USA The Catholic University of America USA

Cetaceans are aquatic mammals living in an environment that is more suited for hearing than *** such,their sensory systems largely utilize acoustic cues for navigation,communication,foraging,and predator ***,the elevation of underwater sound levels from increased human activities has adversely affected cetaceans’use of sound to perform vital life *** address those impacts,scientific studies have been conducted to understand the behavioral,psychoacoustical,physiological,and physical responses by cetaceans that have been exposed to anthropogenic *** studies range from captive experiments involving auditory thresholds and noise-induced threshold shifts,to field observations of behavioral disturbance from sound exposure,to post-mortem examinations of physical manifestations in stranded *** the years,results from these studies have assisted regulatory agencies in developing a series of criteria and thresholds for cetacean conservation and management around the *** paper provides a high-level overview of worldwide research efforts that have been dedicated to understanding the effects of underwater sound on *** review is not intended to be exhaustive but rather to capture major efforts and significant findings in this *** addition,the review excludes synthesis studies and modeling exercises that do not involve direct research on target species.

关键词： Cetacean Anthropogenic sound Underwater sound exposure Behavioral disturbance Environmental impact assessment Behavioral response Noise-induced threshold shift

MEMS-actuated metasurface Alvarez lens

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Microsystems & Nanoengineering 2020年第1期6卷 334-344页

作者： Zheyi Han shane Colburn Arka Majumdar Karl F.Bohringer Department of Electrical and Computer Engineering University of WashingtonSeattleWashington 98195USA Institute for Nano-Engineered Systems University of WashingtonSeattleWashington 98195USA Department of Physics University of WashingtonSeattleWashington 98195USA Department of Bioengineering University of WashingtonSeattleWashington 98195USA

Miniature lenses with a tunable focus are essential components for many modern applications involving compact optical *** several tunable lenses have been reported with various tuning mechanisms,they often face challenges with respect to power consumption,tuning speed,fabrication cost,or production *** this work,we have adapted the mechanism of an Alvarez lens–a varifocal composite lens in which lateral shifts of two optical elements with cubic phase surfaces give rise to a change in the optical power–to construct a miniature,microelectromechanical system(MEMS)-actuated metasurface Alvarez *** based on an electrostatic MEMS generates fast and controllable actuation with low power *** utilization of metasurfaces–ultrathin and subwavelength-patterned diffractive optics–as optical elements greatly reduces the device volume compared to systems using conventional freeform *** entire MEMS Alvarez metalens is fully compatible with modern semiconductor fabrication technologies,granting it the potential to be mass-produced at a low unit *** the reported prototype operating at 1550 nm wavelength,a total uniaxial displacement of 6.3µm was achieved in the Alvarez metalens with a direct-current(DC)voltage application up to 20V,which modulated the focal position within a total tuning range of 68µm,producing more than an order of magnitude change in the focal length and a 1460-diopter change in the optical *** MEMS Alvarez metalens has a robust design that can potentially generate a much larger tuning range without substantially increasing the device volume or energy consumption,making it desirable for a wide range of imaging and display applications.

关键词： electrostatic optics adapted

Prevalence of depression in coronary heart disease in China：a systematic review and meta-analysis

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Chinese Medical Journal 2014年第16期127卷 2991-2998页

作者： Ren Yanping Yang Hui Colette Browning shane Thomas Liu Meiyan Department of Geriatric-Cardiology First Hospital of Xi'an JiaotongUniversity Xi'an Shannxi 710061 China School of Primary Health Care Faculty of Medicine Nursing andHealth Sciences Victoria 3165 Monash University Australia Department of Cardiology Beijing Anzhen Hospital Affiliated toCapital Medical University Beijing 100029 China

Background Coronary heart diseases （CHD） have been identified as one of topmost diseases affecting the Chinese ***,depression in CHD has not been reported and there are limited high quality empirical studies in China focused on the prevalence of the *** study aimed to estimate the pooled prevalence of depression with CHD in *** Systematic review and meta-analysis of published epidemiologic studies on the depression in CHD patients in China were *** research findings dated before 30 September 2013 were obtained from Ovid Medline,EMBASE and two Chinese electronic publication libraries WANFANG and *** used ＂cardiovascular disease＂,＂depression＂ and ＂China＂ as the search themes in Ovid Medline and EMBASE and ＂cardiovascular disease＂ and ＂depression＂ in WANFANG and ***-effects meta-analysis was used to estimate the prevalence of depression in CHD *** Twenty-seven studies were included in the ***-three studies had 5 236 participants who were hospitalized and four studies had 1 353 participants from *** overall prevalence of depression in CHD from hospital was 51% （95% CI：0.43,0.58; Ⅰ-squared=97%,P=-0.000）.The prevalence of depression in CHD from community ranged between 34.6% to 45.8%,and the severe depression was found ranging between 3.1% to 11.2%.Conclusions On comparing data with other countries,the prevalence of depression in CHD among admitted patients in China was found to be *** physicians and healthcare providers should pay more attention to the ＂physical-mental＂ health of the CHD patients.

关键词： prevalence depression coronary heart disease China meta-analysis

Fabrication of 3D Templates Using a Large Depth of Focus Femtosecond Laser

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Chinese Physics Letters 2009年第9期26卷 140-142页

作者：李晓凡 WINFIELD Richard O'BRIEN shane 陈良尧 Department of Optical Science and Engineering Fudan University Shanghai 200433 Tyndall National Institute Lee Maltings Prospect Row Cork Ireland Department of Microelectronic Engineering University College Cork Cork Ireland

We report the use of a large depth of focus Bessel beam in the fabrication of cell structures. Two axicon lenses are investigated in the formation of high aspect ratio line structures. A sol-gel resin, with good mechanical strength, is polymerised in a modified two-photon polymerisation system. Examples of different two-dimensional grids are presented to show that the lateral resolution can be maintained even in the rapid fabrication of high-sided structures.

关键词： sea surface nonliear interaction numerical method

Fast extended depth of focus meta-optics for varifocal functionality

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Photonics Research 2022年第3期10卷 828-833页

作者： James E.M.Whitehead Alan Zhan shane Colburn Luocheng Huang Arka Majumdar Department of Electrical and Computer Engineering University of WashingtonSeattleWashingtonD.C.98195USA Tunoptix SeattleWashingtonD.C.98195USA Department of Physics University of WashingtonSeattleWashingtonD.C.98195USA

Extended depth of focus(EDOF)optics can enable lower complexity optical imaging systems when compared to active focusing *** existing EDOF optics,however,it is difficult to achieve high resolution and high collection efficiency *** subwavelength spacing of scatterers in a meta-optic enables the engineering of very steep phase gradients;thus,meta-optics can achieve both a large physical aperture and a high numerical ***,we demonstrate a fast(f/1.75)EDOF meta-optic operating at visible wavelengths,with an aperture of 2 mm and focal range from 3.5 mm to 14.5 mm(286 diopters to 69 diopters),which is a 250×elongation of the depth of focus relative to a standard ***-independent performance is shown by imaging at a range of finite conjugates,with a minimum spatial resolution of∼9.84μm(50.8 cycles/mm).We also demonstrate operation of a directly integrated EDOF meta-optic camera module to evaluate imaging at multiple object distances,a functionality which would otherwise require a varifocal lens.

关键词： optics enable otherwise