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Finding the magnetopause location using soft X-ray observations and a statistical inverse method

Earth and Planetary Physics 2024年第1期8卷 184-203页

作者： Gonzalo Cucho-Padin Hyunju Connor Jaewoong Jung brian walsh David G.Sibeck Space Weather Laboratory NASA Goddard Space Flight CenterGreenbeltMDUSA Department of Physics The Catholic University of AmericaWashingtonDCUSA Geospace Physics Laboratory NASA Goddard Space Flight CenterGreenbeltMDUSA Astronomy Department University of Maryland College ParkCollege ParkMDUSA Center for Space Physics Department of Mechanical EngineeringBoston UniversityBostonMAUSA

Variability in the location and shape of the dayside magnetopause is attributed to magnetic reconnection,a fundamental process that enables the transfer of mass,energy,and momentum from the solar wind into the *** spatial and temporal properties of the magnetopause,under varying solar and magnetospheric conditions,remain largely unknown because empirical studies using in-situ observations are challenging to *** wide field-of-view(FOV)imaging is the only means to simultaneously observe the spatial distribution of the plasma properties over the vast dayside magnetospheric region and,subsequently,quantify the energy transport from the interplanetary medium into the terrestrial *** upcoming missions,ESA/CAS SMILE and NASA’s LEXI will provide wide-field imagery of the dayside magnetosheath in soft X-rays,an emission generated by charge exchange interactions between high charge-state heavy ions of solar wind origin and exospheric neutral ***-cadence two-dimensional observations of the magnetosheath will allow the estimation of dynamic properties of its inner boundary,the magnetopause,and enable studies of its response to changes in the solar wind dynamic pressure and interplanetary magnetic field *** work introduces a statistically-based estimation approach based on inverse theory to estimate the spatial distribution of magnetosheath soft X-ray emissivities and,with this,identify the location of the magnetopause over the Sun−Earth *** do so,we simulate the magnetosheath structure using the MHD-based OpenGGCM model and generate synthetic soft X-ray images using LEXI’s orbit and attitude *** results show that 3-D estimations using the described statistically-based technique are robust against Poisson-distributed shot noise inherent to soft X-ray ***,our proposed methodology shows that the accuracy of both three-dimensional(3-D)estimation and the magnetopause standoff distance calculation hi

关键词： magnetopause soft X-ray tomography

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Evaluation of a Dry Extract System Involving NIR Spectroscopy (DESIR) for Rapid Assessment of Pesticide Contamination of Fruit Surfaces

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American Journal of Analytical Chemistry 2012年第8期3卷 524-533页

作者： Umesh Kumar Acharya Phul Prasad Subedi kerry brian walsh Central Queensland University Institute for Resource Industries and Sustainability Plant Science Group Rockhampton Australia

The dry-extract system for (near) infrared (DESIR) technique was implemented using reflectance near-infrared spec-troscopy in context of detection of contact pesticide residues on fruit. Based on chemical structure, spectra features and regression statistics for PLSR models, a product containing metiram and pyraclostrobin was chosen from six pesticides for further consideration. Regression models based on spectra of dry extracts of aqueous solutions and either acetone or water washes of contaminated fruit were encouraging (RMSECV of approximately 0.03 - 0.06 mg a.i.). This level of analytical performance would support the use of the technique as a rapid screening tool, with suspect samples then subject to the reference GC-MS analysis method. However, the PLSR model performance was poor across populations of fruit, suggesting that matrix changes in the solvent wash between sets of fruit is problematic. Further work is required to establish whether sufficient variation can be built into a calibration set to overcome this issue, without degrading model performance to the point where it loses practical application.

关键词： Apple Mango Tomato Fungicide Insecticide Aero Metiram Pyraclostrobin Octave Prochloraz Penncozeb Mancozeb Amistar Azoxystrobin Applaud Buprofezin Lorsban Chlorpyrifos Near Infrared Pesticide

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Estimating the subsolar magnetopause position from soft X-ray images using a low-pass image filter

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Earth and Planetary Physics 2024年第1期8卷 173-183页

作者： Hyangpyo Kim Hyunju K.Connor Jaewoong Jung brian M.walsh David Sibeck Kip D.Kuntz Frederick S.Porter Catriana K.Paw U Rousseau A.Nutter Ramiz Qudsi Rumi Nakamura Michael Collier Space Research Institute Austrian Academy of Sciences8042 GrazAustria Geophysical Institute University of Alaska FairbanksFairbanksAlaska 99775USA National Aeronautics and Space Administration(NASA)Goddard Space Flight Center GreenbeltMaryland 20771USA Astronomy Department University of Maryland College ParkCollege ParkMaryland 20742USA Center for Space Physics Boston UniversityBostonMassachusetts 02215USA Department of Physics and Astronomy Johns Hopkins UniversityBaltimoreMaryland 21218USA Howard University WashingtonDC 20059USA

The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective launches in the near future,to specify glo bal magnetic reconnection modes for varying solar wind *** suppo rt the success of these scientific missions,it is critical to develop techniques that extract the magnetopause locations from the observed soft X-ray *** this research,we introduce a new geometric equation that calculates the subsolar magnetopause position(RS)from a satellite position,the look direction of the instrument,and the angle at which the X-ray emission is *** assumptions are used in this method:(1)The look direction where soft X-ray emissions are maximized lies tangent to the magnetopause,and(2)the magnetopause surface near the subsolar point is almost spherical and thus RSis nea rly equal to the radius of the magneto pause *** create synthetic soft X-ray images by using the Open Geospace General Circulation Model(OpenGGCM)global magnetohydrodynamic model,the galactic background,the instrument point spread function,and Poisson *** then apply the fast Fourier transform and Gaussian low-pass filte rs to the synthetic images to re move noise and obtain accurate look angles for the soft X-ray pea *** the filte red images,we calculate RS and its accuracy for different LEXI locations,look directions,and solar wind densities by using the OpenGGCM subsolar magnetopause location as ground *** method estimates RS with an accuracy of10 *** accuracy improves for greater solar wind densities and during southward interplanetary magnetic *** method ca ptures the magnetopause motion during southwa rd interplaneta ry magnetic field ***,the technique will enable quantitative analysis of the magnetopause motion and help reveal the daysi

关键词： soft X-ray magnetopause reconnection low-pass filter LEXI SMILE

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In vitro C ytotoxic Properties of Crude Polar Extracts of Plants Sourced from Australia

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Clinical Complementary Medicine and Pharmacology 2022年第1期2卷 13-22页

作者： Janice Mani Joel Johnson Holly Hosking kerry walsh Paul Neilsen Mani Naiker School of Health Medical and Applied SciencesCentral Queensland UniversityBruce HwyNorth RockhamptonQueensland 4701Australia Institute of Future Farming Systems Central Queensland UniversityBruce HwyNorth RockhamptonQueensland 4701Australia

Background:Numerous commercial pharmaceuticals-including anticancer,antiviral,and antidiabetic drugs have been developed from traditional plant-derived *** are approximately 25,000 species of flora occurring in Australia,which are adapted to a range of harsh environments,and hence a plethora of novel compounds are still awaiting research in the context of their medicinal ***:The current study therefore aimed to develop a systematic protocol for screening plants with potential *** studies have found polar compounds such as to be the bioactive components responsible for the therapeutic ***:The total phenolic content(TPC)and antioxidant capacity(FRAP)of methanolic extracts of selected plants was first determined.A high correlation between the TPC values and FRAP values of the plant polar extracts were *** viability of the cancer cell lines were assessed using the MTS ***:Cells subjected to Pittosporum angustifolium *** at concentration of 250μg/mL showed no viable cells,comparable to cisplatin(a chemotherapy medication)used as a positive control(10μg/mL).Some promising inhibitory effects were also seen with Murrya koenigii flower and leaves at concentration of 250μg/mL,with only 43.46%and 63.88%cell viability,*** contrast,extracts of Citrus hystrix(leaves)and Sygyz-ium australe(stamen)showed higher percentage cell viabilities(around 82-93%)at same *** phenolic profile of *** B extracts demonstrating greater peak intensity and dominant peaks were tentatively identified as chlorogenic acid,p-coumaric acid,caffeic acid,t-ferulic acid and ***:The Australian species *** extract was the most cytotoxic against HeLa and HT29 cells comparing to the other plant extracts tested.A HPLC profile of the *** extract also showed an array of promising therapeutic phenolic *** work will aim to fractionate and isolate

关键词： Cytotoxic Antioxidant capacity Total phenolics Australian plants Polar extracts

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Antilisterial Activity of Lactose Fatty Acid Esters in Milk

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Food and Nutrition Sciences 2019年第7期10卷 750-760页

作者： Seung-Min Lee brian Nummer brian Nummer Ashwini Wagh Marie K. walsh Department of Nutrition Dietetics and Food Sciences Utah State University Logan Utah USA The Clorox Service Company Pleasanton California USA

Carbohydrate fatty acid esters have been shown to inhibit the growth of bacteria in growth media. In this study, the antilisterial activities of the carbohydrate esters lactose monodecanoate (LMD) and lactose monolaurate (LML) were tested in milk samples with variable fat content (up to 10%) and at different temperatures (37°C, 24°C and 5°C) after inoculation with a 5-strain Listeria monocytogenes cocktail. Both LMD and LML demonstrated antilisterial properties against L. monocytogenes in milk, with the observed log reductions in the LMD milk samples being higher than those in the LML samples at all tested temperatures. LMD in 1% and 2% fat milk was found to be bactericidal with no Listeria growth by day 6. LMD showed significant antilisterial activity in milk samples containing up to 9% fat at 37°and in samples with up to 3.5% fat at 24°C and in milk samples with up to 2% fat at 5°C. LML showed significant Listeria log reductions at 37°C with milk containing up to 9% fat but showed no microbial inhibition in milk in any samples at 24°C and 5°C. Although carbohydrate fatty acid esters have proven microbial bactericidal/bacteriostatic properties in growth media, their antimicrobial properties are reduced in a food system containing fat and at temperatures lower than 37°C. The significance of this research is identifying food constituents and storage temperatures that limit the microbial inhibitory properties of lactose esters to ensure appropriate use as potential food grade antilisterial agents.

关键词： Lactose Monodecanoate Lactose Monolaurate Antilisterial Activity Milk Fat Temperature

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An Analog Method for Seasonal Forecasting in Northern High Latitudes

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Atmospheric and Climate Sciences 2021年第3期11卷 469-485页

作者： John E. walsh brian Brettschneider Nathan P. Kettle Richard L. Thoman International Arctic Research Center University of Alaska Fairbanks Fairbanks Alaska USA National Weather Service Alaska Region NOAA Anchorage Alaska USA

An analog forecast method designed for monthly and seasonal outlooks is applied to the Arctic. The analog selection process uses pattern matches based on agreement with historical data to identify past years with similar distributions of sea level pressure, upper-air geopotential height, surface and upper-air temperatures, precipitation, and sea surface temperatures. The evolution of the atmosphere in the analog years is then the basis of a prediction for the target year. Users can choose the predictor domain, the predictand domain, the variable to be predicted, and the number of antecedent months on which the analog selection is based. We provide an example of a monthly forecast generated by the analog forecast tool. In comparisons with operational dynamical model forecasts over the period 2012-2019, the analog system underperforms the dynamical models in middle latitudes but generally outperforms the dynamical models in monthly forecasts of surface air temperatures in the Arctic. The improvement over the dynamical models is especially apparent in the late summer and early autumn (August-October).

关键词： Arctic Climate Analog Forecasting

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Satellite remote sensing of grasslands:from observation to management

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Journal of Plant Ecology 2016年第6期9卷 649-671页

作者： Iftikhar Ali Fiona Cawkwell Edward Dwyer brian Barrett Stuart Green Department of Geography University College CorkCorkIreland Spatial Analysis Unit TeagascDublinIreland EurOcean-European Centre for Information on Marine Science and Technology LisbonPortugal School of Geographical and Earth Sciences University of GlasgowGlasgowUK

Aims Grasslands are the world’s most extensive terrestrial ecosystem,and are a major feed source for *** increasing demand for meat and other dairy products in a sustainable manner is a big *** a field scale,Global Positioning System and ground-based sensor technologies provide promising tools for grassland and herd management with high *** the growth in availability of spaceborne remote sensing data,it is therefore important to revisit the relevant methods and applications that can exploit this *** this article,we have reviewed the(i)current status of grassland monitoring/observation methods and applications based on satellite remote sensing data,(ii)the technological and methodological developments to retrieve different grassland biophysical parameters and management characteristics(***,grazing intensity)and(iii)identified the key remaining challenges and some new upcoming trends for future *** Findings The retrieval of grassland biophysical parameters have evolved in recent years from classical regression analysis to more complex,efficient and robust modeling approaches,driven by satellite data,and are likely to continue to be the most robust method for deriving grassland information,however these require more high quality calibration and validation *** found that the hypertemporal satellite data are widely used for time series generation,and particularly to overcome cloud contamination issues,but the current low spatial resolution of these instruments precludes their use for field-scale application in many *** trend may change with the current rise in launch of satellite constellations,such as RapidEye,Sentinel-2 and even the microsatellites such as those operated by Skybox *** imagery has not been widely used for grassland applications,and a better understanding of the backscatter behaviour from different phenological stages is needed for more reliable products i

关键词： remote sensing agricultural grassland grassland biomass pasture management grazing intensity

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钢带加固路堤的稳定性

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路基工程 1996年第4期 75-85页

作者： R.kerry Rowe brian L.J.Mylleville 孙增生铁科院西北分院

本文研究了建筑在软粘性沉积物上采用钢带进行了加固的路堤不排水性质,应用了路堤和基础的塑性破坏、钢带的抗拔力和加筋的潜在极限的有限元分析,以证明钢带加固能改善路堤的稳定性。在不排水抗剪强度随深度增大的土强度分布范围内,研... 详细信息

本文研究了建筑在软粘性沉积物上采用钢带进行了加固的路堤不排水性质,应用了路堤和基础的塑性破坏、钢带的抗拔力和加筋的潜在极限的有限元分析,以证明钢带加固能改善路堤的稳定性。在不排水抗剪强度随深度增大的土强度分布范围内,研究了钢带间距对破坏模式和路堤稳定性的影响。提出了一种分析钢带加固路堤的简单方法,并通过计算实例加以说明。然后基于仅考虑了承载力和极限平衡的设计与完全有限元分析结果进行了对比,发现前者比后者稍微保守一点。

关键词：加固钢带有限元稳定性铁路路堤软土地基

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