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The effect of the equatorially symmetric zonal winds of Saturn on its gravitational field

Research in Astronomy and Astrophysics 2018年第4期18卷 15-22页

作者： Dali Kong Keke Zhang Gerald Schubert j.hn D.anderson Key Laboratory of Planetary Sciences Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030 China College of Engineering Mathematics and Physical Sciences University of Exeter Exeter EX4 4QF UK Lunar and Planetary Science Laboratory Macao University of Science and Technology Macao China Department of Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA j.t Propulsion Laboratory 4800 Oak Grove Drive Pasadena CA 91109 USA

The penetration depth of Saturn’s cloud-level winds into its interior is unknown.A possible way of estimating the depth is through measurement of the effect of the winds on the planet’s gravitational *** use a self-consistent perturbation approach to study how the equatorially symmetric zonal winds of Saturn contribute to its gravitational *** important advantage of this approach is that the variation of its gravitational field solely caused by the winds can be isolated and identified because the leading-order problem accounts exactly for rotational distortion,thereby determining the irregular shape and internal structure of the hydrostatic *** assume that（i）the zonal winds are maintained by thermal convection in the form of non-axisymmetric columnar rolls and（ii）the internal structure of the winds,because of the Taylor-Proundman theorem,can be uniquely determined by the observed cloud-level *** calculate both the variation △j.n,n=2,4,6...of the axisymmetric gravitational coefficients j.n caused by the zonal winds and the non-axisymmetric gravitational coefficients △j.（nm） produced by the columnar rolls,where m is the azimuthal wavenumber of the *** consider three different cases characterized by the penetration depth 0.36 R_S,0.2 R_S and 0.1 R_S,where R_S is the equatorial radius of Saturn at the 1-bar pressure *** find that the high-degree gravitational coefficient （ j.（12）＋△j.（12）） is dominated,in all the three cases,by the effect of the zonal flow with ｜△j.（12）/j.（12）｜〉100%and that the size of the non-axisymmetric coefficientsdirectly reflects the depth and scale of the flow taking place in the Saturnian interior.

关键词： gravitation — planets and satellites individual(Saturn) — planets and satellites interiors

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Crystal-oriented wrinkles with origami-type j.nctions in few-layer hexagonal boron nitride

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Nano Research 2015年第5期8卷 1680-1688页

作者： Camilla K. Oliveira Egleidson F. A. gomes Mariana C. Prado Thonimar V. Alencar Regiane Nascimento Leandro M. Malard Ronaldo j. C. Batista Alan B. de Oliveira Helio Chacham Ana M. de Paula Bernardo R, A. Neves Departamento de Fisica ICEx Universidade Federal de Minas Gerais - UFMG C.P. 702 30123-970 - Belo Horizonte Brazil Departamento de Fisica ICEB Universidade Federal de Ouro Preto - UFOP 35400-000 - Ouro Preto Brazil

Understanding layer interplay is the key to utilizing layered heterostructures formed by the stacking of different two-dimensional materials for device applications. Boron nitride has been demonstrated to be an ideal substrate on which to build graphene devices with improved mobilities. Here we present studies on the morphology and optical response of annealed few-layer hexagonal boron nitride flakes deposited on a silicon substrate that reveal the formation of linear wrinkles along well-defined crystallographic directions. The wrinkles formed a network of primarily threefold and occasionally fourfold origami-type j.nctions throughout the sample, and all threefold j.nctions and wrinkles formed along the armchair crystallographic direction. Furthermore, molecular dynamics simulations yielded, through spontaneous symmetry breaking, wrinkle j.nction morphologies that are consistent with both the experimental results and the proposed origami-folding model. Our findings indicate that this morphology may be a general feature of several two-dimensional materials under proper stress-strain conditions, resulting in direct consequences in device strain engineering.

关键词： hexagonal boron nitride 2D materials wrinkles origami folding annealing

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Initial Experience with Tricortical Iliac Crest Bone Graft and Human Amniotic Allograft in Evans Calcaneal Osteotomy

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Stem Cell Discovery 2015年第2期5卷 11-17页

作者： j. j.seph anderson Adam F. Gough Myron H. Hansen Zflan Swayzee New Mexico Bone & j.int Institute Alamogordo NM USA Silver Medicine Group Silver City NM USA Cactus Foot & Ankle Gilbert AZ USA

Background: Adult acquired flatfoot deformity is generally mediated with an Evans procedure where a wedge of bone is placed into the calcaneus to better align the foot and decrease the deformity. The purpose of this study was to assess the efficacy and safety of human amniotic allograft applied to allogeneic tri-cortical grafts in Evans calcaneal osteotomy. Methods: The medical records of patients who had Evans calcaneal osteotomy with implantation of tri-cortical iliac crest bone graft with human anmiotic allograft for surgical management of adult acquired flatfoot deformity with 2 years follow-up data were reviewed. Results: A total of 63 patients (mean age: 33.3 yr, range: 18 - 66 yr) were enrolled with adult acquired flatfoot deformity. Median time to weight-bearing was 6 weeks. Time to wearing normal shoes was 10 weeks, and time to radiographic healing was 16 weeks. Conclusions: The use of human amniotic allograft did not diminish the long term outcome of procedure or the short term benchmarks for healing after surgery. There were no nonunion, wound dehiscence, infection, or allergic or immune reaction reported. This retrospective study demonstrated that tri-cortical iliac crest bone graft and HAA could be safely used in Evans calcaneal osteotomy with favorable results.

关键词： Adult Acquired Flatfoot Deformity Bone Graft Calcaneal Osteotomy Evans Procedure Human Amniotic Allograft

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Performance of a Direct Inj.ction of IC Engine on SVO and Biodiesel from Multiple Feedstocks

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j.urnal of Power and Energy Engineering 2014年第8期2卷 1-13页

作者： Syndi Nettles-anderson Daniel B. Olsen j.rry j. j.hnson j.an-Nicolas Enj.lbert Engines & Energy Conversion Laboratory Mechanical Engineering Department Colorado State University Fort Collins USA Soil & Crop Sciences Department Colorado State University Fort Collins USA

Straight Vegetable Oil (SVO) is a promising biofuel with a low energy input to energy output ratio. Successful use of SVO in engines depends on engine performance, wear and emissions. This study focuses on short term engine emissions and performance. This research uses oils produced in Colorado as a full diesel fuel substitute in a modified single cylinder engine. This engine testing was conducted in the laboratory. The test engine was a Yanmar TF140E, which is naturally aspirated and uses low pressure (~140 bar) mechanical direct inj.ction. The engine fuel system was modified to accommodate a 2-tank custom SVO kit. The SVO was heated to 75 °C. Fuel economy and emissions measurements were performed for petroleum diesel, four different vegetable oils (sunflower, canola, camelina, and soybean) and their biodiesel derivatives. Fuel mass flow, oxides of nitrogen (NOX), total hydrocarbons (THC), carbon monoxide (CO), and particulate matter were measured. No engine degradation was experienced through approximately 50 hrs of testing on SVO and 50 hrs of testing on biodiesel. Overall engine emissions for SVO and biodiesel, with the exception of THC for biodiesel, were higher than petroleum diesel. More favorable biofuel emissions comparisons to diesel are expected with other engine designs based on data from various literature sources. Data comparing raw and refined SVO indicate that refined vegetable oil produces lower particulate matter (PM) emissions. General trends were observed showing that oils with higher levels of polyunsaturated fats (e.g. C18:1, C18:2, and C18:3) produce higher levels of NOX and THC’s.

关键词： Straight Vegetable Oil Biodiesel Camelina Alternative Fuels Engine Performance Exhaust Emissions

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Rapid Determination of Gold during Plating Operations by Portable X-Ray Fluorescence

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American j.urnal of Analytical Chemistry 2014年第17期5卷 1178-1183页

作者： Brandon j. Burnett Andrew Giles Arthur L. anderson Terry Darger Edward Walker Department of Chemistry Snow College Richfield UT USA Department of Chemistry Weber State University Ogden UT USA Gold Plating Services Layton UT USA

We present the analysis of gold in plating solutions in the presence of several additive ions by portable X-ray fluorescence (XRF) revealing an optimum potassium gold cyanide concentration of 2 - 3 g/L for maximum cathode efficiency. Additionally, we present the utility of XRF to determine the thickness of gold plated on copper substrates up to 6 microns.

关键词： Cathode Efficiency Electrochemistry Gold Plating X-Ray Fluorescence

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Fucoidan and topography modification improved in situ endothelialization on acellular synthetic vascular grafts

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生物活性材料(英文) 2023年第4期22卷 535-550页

作者： Yuan Yao Aung Moe Zaw Deirdre E.j.anderson Yej.n j.ong j.shua Kunihiro Monica T.Hinds Evelyn K.F.Yim Department of Chemical Engineering University of Waterloo200 University Avenue WestWaterlooONN2L 3G1Canada Department of Biomedical Engineering Oregon Health&Science UniversityPortlandOR97239USA Waterloo Institute for Nanotechnology University of Waterloo200 University Avenue WestWaterlooONN2L 3G1Canada Center for Biotechnology and Bioengineering University of Waterloo200 University Avenue WestWaterlooONN2L 3G1Canada

Thrombogenesis remains the primary failure of synthetic vascular *** coverage is crucial to provide an antithrombogenic ***,most synthetic materials do not support cell adhesion,and transanastomotic endothelial migration is ***,a surface modification strategy using fucoidan and topography was developed to enable fast in situ endothelialization of polyvinyl alcohol,which is not endothelial *** three different immobilization approaches compared,conj.gation of aminated-fucoidan promoted endothelial monolayer formation while minimizing thrombogenicity in both in vitro platelet rich plasma testing and ex vivo non-human primate shunt *** of six topographical patterns showed that 2μm gratings increased endothelial cell migration without inducing inflammation responses of endothelial *** studies demonstrated that fucoidan could attract fibronectin,enabling integrin binding and focal adhesion formation and activating focal adhesion kinase(FAK)signaling,and 2μm gratings further enhanced FAK-mediated cell *** a clinically relevant rabbit carotid artery end-to-side anastomosis model,60%in situ endothelialization was observed throughout the entire lumen of 1.7 mm inner diameter modified grafts,compared to 0%of unmodified graft,and the four-week graft patency also *** work presents a promising strategy to stimulate in situ endothelialization on synthetic materials for improving long-term performance.

关键词： Blood-contacting devices Small diameter vascular graft Endothelialization Topography Fucoidan

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Investigation of the Anti-Mycobacterial Mechanism of Action of 7-Methylj.glone

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Open j.urnal of Respiratory Diseases 2012年第2期2卷 60-62页

作者： Veneesha Thaver j. j. M. Meyer Riana Cockeran Moloko C. Cholo Ronald anderson Namrita Lall Department of Physiology University of Limpopo Medical University of South Africa Campus Pretoria South Africa Department of Plant Science Faculty of Natural and Agricultural Sciences University of Pretoria Pretoria South Africa MRC Unit for Inflammation and Immunity Department of Immunology Faculty of Health Sciences University of Pretoria and Tshwane Academic Division of the National Health Laboratory Service Pretoria South Africa

Obj.ctives: Although the naphthoquinone, 7-methylj.glone (7-Mj., is active against Mycobacterium tuberculosis (MTB) in vitro, neither the cellular site nor mechanism of anti-mycobacterial action of this agent has been identified. The primary obj.ctive of the current study was to investigate the mycobacterial outer membrane as a potential target of 7-Mj.by measuring the effects of this agent (0.023 - 1.5 mg/L) on microbial ATP levels and uptake of K+ . Methods: Bioluminescence and radiometric (uptake of 86Rb+) procedures were used to assay microbial ATP levels and K+ transport respectively. Results: Exposure of MTB (strain H37Rv) to 7-Mj.for 60 min resulted in dose-related decreases in both microbial ATP levels and uptake of 86Rb+ which achieved statistical significance (P + transport.

关键词： Adenosine Triphosphate Cell Membrane Energy Metabolism Potassium

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The influence of soil on vegetation structure and plant diversity in different tropical savannic and forest habitats

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j.urnal of Plant Ecology 2018年第2期11卷 226-236页

作者： Priscyla Maria Silva Rodrigues Carlos Ernesto Gonçalves Reynaud Schaefer j.onathan de Oliveira Silva Walnir gomes Ferreira j.nior Rubens Manoel dos Santos Andreza Viana Neri Universidade Federal do Vale do São Francisco Campus Senhor do BonfimColegiado de EcologiaAv.Tomaz GuimarãesS/NBairro Santos DumontSenhor do BonfimBACEP 48.970-000Brazil Universidade Federal de Viçosa Departamento de SolosCampus UniversitárioViçosaMGCEP 36570-900Brazil Instituto Federal de Educação Ciência e Tecnologia do Sul de Minas GeraisRodovia Machado-ParaguaçuKm 3MachadoMGCEP 37750-000Brazil Universidade Federal de Lavras Departamento de Ciências FlorestaisLaboratório de Conservação e Manejo da BiodiversidadeCampus UniversitárioLavrasMGCEP 37200-000Brazil Universidade Federal de Viçosa Departamento de Biologia VegetalLaboratório de Ecologia e Evolução de PlantasCampus UniversitárioViçosaMGCEP 36570-900Brazil

Aims Soil plays an important role in the formation and heterogene-ity of habitats and thus can cause changes in vegetation struc-ture and plant *** differentiation between Cerrado/savanna and forest is well known,but the relationship between soil and habitats from savannic or forest formations still needs to be better understood,particularly in tropical ecotonal *** studied the association between attributes of plant com-munities,namely structure and diversity,and physicochemical characteristics of soils in the Caatinga domain at the transition to Cerrado in *** Chemical and physical analyses of soils were performed in samples of 38 plots from savannic formations and 30 plots from forest *** was characterized floristically and structurally in all plots,five habitats being assessed in each plant *** features and vegetation parameters were highly distinct among the different *** Findingsin general,forest habitats were more nutrient rich than savannic ***,soil variables showed effects both on vegetation structure and on its species diversity,more pronouncedly in the savannic *** were structurally distinct,and diversity differed between savannic and forest communities;however,a higher differentiation occurred when the savannic formation habitats were compared among *** plant diversity did not differ among forest formation habitats,soil attributes showed a close relationship with edaphic factors and can contribute for similar *** soil-vegetation relationship in highly diverse ecotonal landscapes is important from the conservation biology point of view and aid in the execution of proactive plans for the maintenance of ***,we noticed that diversity and soil behaves distinctly between savannic and forest communities.

关键词： Cerrado dry forest edaphic variation vegetation-soil relationship ecotone

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Development and Validation of a Questionnaire to Measure Health Professionals’ Attitudes toward Identification of Female Victims of Domestic Violence

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Health 2015年第5期7卷 596-605页

作者： Huong Thi Thanh Nguyen Debra j. anderson Michael P. Dunne Huong Thanh Nguyen School of Nursing Queensland University of Technology Brisbane Australia Faculty of Nursing and Midwifery Hanoi Medical University Hanoi Vietnam School of Public Health and Social Work Queensland University of Technology Brisbane Australia Institute for Community Health Research Hue University of Medicine and Pharmacy Hue Vietnam Hanoi School of Public Health Hanoi Vietnam

Back ground: Domestic violence against women is a maj.r public health problem and violations of women’s human rights. Health professionals could play an important role in screening for the victims. From the evidence to date, it is unclear whether health professionals do play an active role in identification of the victims. Obj.ctives: To develop a reliable and valid instrument to measure health professionals’ attitude to identifying female victims of domestic violence. Methods: A primary questionnaire was constructed in accordance with established guidelines using the Theory of Planned Behaviour Aj.en (1975) to develop an instrument to measure health professionals’ attitudes in identifying female victim of DV. An expert panel was used to establish content validity. Focus groups amongst a group of health professionals (N = 5) of the target population were performed to confirm face validity. A pilot study (N = 30 nurses and doctors) was undertaken to elicit the feasibility and reliability of the questionnaire. The questionnaire was also administered a second time after one week to check the stability of the tests. Results: Feedbacks of the expert panel’s and group discussion confirmed that the questionnaire had the content and face validity. Cronbach’s alpha values for all the items were greater than 0.7. Strong correlations between the direct and indirect measures confirmed that the indirect measures were well constructed. High test-retest correlations confirmed that the measures were reliable in the sense of temporal stability. Significance: This tool has the potential to be used by researchers in expanding the knowledge base in this important area.

关键词： Domestic Violence Questionnaire Development Health Professionals

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Validation of a radioimmunoassay-based fecal corticosteroid assay for Richardson＇s ground squirrels Urocitellus richardsonii and behavioural correlates of stress

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Current Zoology 2014年第5期60卷 591-601页

作者： j.mes F. HARE Calen R RYAN Chris ENRIGHT Laura E. GARDINER Lindsay j.SKYNER Charlene N. BERKVENS W. Gary anderson Department of Biological Sciences University of Manitoba Winnipeg MB Canada R3T 2N2 Assiniboine Park Zoo Winnipeg MB Canada R3R 2N7 Present Address: School of Applied Science Bay of Plenty Polytechnic Tauranga 3112 New Zealand

We validated a radioimmunoassay-based method quantifying fecal glucocorticoid metabolites （FGMs） from captive male and female Richardson＇s ground squirrels Urocitellus richardsonii. Blood samples were drawn to explore the correlation between plasma cortisol and FGM concentrations. We also inj.cted groups of squirrels with normal saline （CTL; control）, adre- nocorticotropic hormone （ACTH; stimulating adrenal activity）, or dexamethasone （DEX; suppressing adrenal activity）. Potential correlations between stress and behaviour were explored through quantification of fecal pellet production and the intervention necessary to elicit defecation, as well as the behaviour of subj.cts in the context of handling. Changes in plasma cortisol concen- tration between capture （baseline）, and following handling （stress-induced） were also quantified for free-living squirrels. While glucocorticoid concentrations recovered from feces during our captive-animal study were not well correlated with plasma eortisol concentrations, and uncorrelated with defecation or behaviour, FGM concentrations did reflect the activation of the hypothalamic- pituitary-adrenal （HPA） axis. FGM concentrations increased significantly during initial captivity, but declined to baseline level as individuals acclimated to the novel environment. Inj.ction of subj.cts with ACTH increased FGMs above baseline, confirming activation of the HPA axis. Plasma cortisol concentrations increased significantly with induced stress, indicating that capture and handling activated the glucocorticoid stress response even among previously handled, free-living subj.cts. Our findings validate a non-invasive tool that will afford new insight into the physiological processes underlying social, reproductive and antipredator behaviour of Richardson＇s ground squirrels [Current Zoology 60 （5）： 591-601, 2014 ].

关键词： Stress Corticosteroids Fecal glucocorticoid metabolites Radioimmunoassay Richardson's ground squirrels

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