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Regional soil Mapping Using Multi-Grade Representative sampling and a Fuzzy Membership-Based Mapping Approach

Pedosphere 2017年第2期27卷 344-357页

作者： YANG Lin A-Xing ZHU ZHAO Yuguo LI Decheng ZHANG Ganlin ZHANG shujie lawrence E. BAND state Key Laboratory of soil and sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) state Key Laboratory of Resources and Environment Information system Institute of Geographical Sciences and Resources Research Chinese Academy of Sciences Beijing 100101 (China) Key Laboratory of Virtual Geographic Environment (Nanjing Normal University) Ministry of Education Nanjing 210023 (China) Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application School of Geography Nanjing Normal University Nanjing 210023 (China) state Key Laboratory Cultivation Base of Geographical Environment Evolution (Jiangsu Province) Nanjing 210023 (China) Department of Geography University of Wisconsin-Madison Madison WI 53706 (USA) China Academy of Urban Planning & Design Beijing 100037 (China) Institute for the Environment University of North Carolina Chapel Hill Chapel Hill NC 27599 (USA)

High-resolution and detailed regional soil spatial distribution information is increasingly needed for ecological modeling and land resource management. For areas with no point data, regional soil mapping includes two steps： soil sampling and soil mapping. Because sampling over a large area is costly, efficient sampling strategies are required. A multi-grade representative sampling strategy, which designs a small number of representative samples with different representative grades to depict soil spatial variations at different scales, could be a potentially efficient sampling strategy for regional soil mapping. Additionally, a suitable soil mapping approach is needed to map regional soil variations based on a small number of samples. In this study, the multi-grade representative sampling strategy was applied and a fuzzy membership-weighted soil mapping approach was developed to map soil sand percentage and soil organic carbon （sOC） at 0-20 and 20-40 cm depths in a study area of 5 900 km2 in Anhui Province of China. First, geographical sub-areas were delineated using a parent lithology data layer. Next, fuzzy c-means clustering was applied to two climate and four terrain variables in each stratum. The clustering results （environmental cluster chains） were used to locate representative samples. Evaluations based on an independent validation sample set showed that the addition of samples with lower representativeness generally led to a decrease of root mean square error （RMsE）. The declining rates of RMsE with the addition of samples slowed down for 20-40 cm depth, but fluctuated for 0-20 cm depth. The predicted sOC maps based on the representative samples exhibited higher accuracy, especially for soil depth 20-40 cm, as compared to those based on legacy soil data. Multi-grade representative sampling could be an effective sampling strategy at a regional scale. This sampling strategy, combined with the fuzzy membership-based mapping approach, could be an optional effec

关键词： fuzzy clustering parent lithology representative grade samphng strategy soil spatial variations

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Long-term trend and abrupt events of the Holocene Asian monsoon inferred from a stalagmiteδ^(18)O record from shennongjia in Central China

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Chinese science Bulletin 2006年第2期51卷 221-228页

作者： sHAO Xiaohua WANG Yongjin CHENG Hai KONG Xinggong WU Jiangying EDWARDs R. lawrence College of Geography science Nanjing Normal University Nanjing 210097 China Department of Geology and Geophysics Minnesota University MN 55455 USA

A high-resolution oxygen-isotope record from a thorium-uranium-dated stalagmite from shanbao Cave at shennongjia reflects variations in the amount of monsoon precipitation for the period from 11.5 to 2.1 ka (1 ka = 1000 cal aBP). Between 11.5 and 9.3 ka, a sharp decrease in δ18O indicates a rapid increase in monsoon precipitation. An interval of generally high monsoon precipitation is observed between 9.3 and 4.4 ka. An arid period has prevailed between 4.4 and 2.1 ka. The long-term trend of shanbao record appears to follow summer insolation at 33°N latitude. An abrupt decrease in monsoon precipitation around 4.3 ka is synchronous with the collapse of Neolithic culture in central China. This abrupt change could have resulted from the amplifi- cation of the gradually decreased summer insolation by the positive vegetation-atmosphere-aerosol feed- back. The weakened Asian monsoon events were in concert with decreased Greenland temperature dur- ing the early Holocene, centered at 8.2, 8.6, 9.3, 10.2 and 11.0 ka. This correlation suggests that changes in low-latitude monsoon are connected with climate change in high-latitude polar region.

关键词：全新世亚洲季风长期趋势突发事件古气候氧同位素中国神龙架石笋

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The anti-inflammatory activity of garden egg(solanuni aethiopicum) on egg albumin-induced oedema and granuloma tissue formation in rats

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Asian Pacific Journal of Tropical Medicine 2012年第1期5卷 62-66页

作者： Anosike Chiuma Assumpta Onyechi Obidoa lawrence U s Ezeanyika Department of Biochemistry University of NigeriaNsukkaEnugu StateNigeria Department of Biochemistry Kogi State UniversityAnyigbaKogi StateNigeria

Objective:To evaluate the possible anti-inflammatory effect of garden egg[solatium aethiopieum (***)]using experimentally induced inflammatory models in ***:Oedema was induced on the rat hind paw In the injection of 0.1 mL undiluted fresh egg albumin(pbilogistic agent) into the subplantar surface of the rat *** granuloma was induced in the rats by the implantation of two autoelaved cotton pellets(30 mg) under the flank o(previously shaved back of anaesthetised *** egg extract doses were administered to the rats for seven consecutive *** dav *** animals were killed and the pellets surrounded by granuloma tissue were disseeled out and ***:Extracts of garden egg significanlly(Psh egg albumin-induced ral paw oedema and also significantly(Pssue formation in the treated groups when compared to the ***:This stud) shows that the fruits of garden egg(***) have anti-inflammatory activity in the models studied.

关键词： solanum aethiopicum Inflammation Oedema reduction Granuloma tissue Rats

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碳化钽粉末的爆炸成形方法

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材料工程 2007年第Z1期35卷 127-130页

作者：徐磊 B.s.Majumdar Darrell Marchant lawrence Matson 青岛科技大学材料科学与工程学院青岛266042 Dept.of Materials and Metallurgical Engineering New Mexico Institute of Mining and Technology PRsM Bldg.845110 E Saturn BoulevardEdwards Air Force Base Wright Patterson Air Force Base Materials Directorate

碳化钽熔点为3880℃,是地球上第二高熔点的物质.其抗腐蚀性能优越,在航空领域有广阔的应用空间.但是传统的材料加工方法,比如热压或者热等静压,会导致晶粒快速长大而得到低的断裂韧性.本文利用爆破方法来克服晶粒长大问题,得到强度和断... 详细信息

碳化钽熔点为3880℃,是地球上第二高熔点的物质.其抗腐蚀性能优越,在航空领域有广阔的应用空间.但是传统的材料加工方法,比如热压或者热等静压,会导致晶粒快速长大而得到低的断裂韧性.本文利用爆破方法来克服晶粒长大问题,得到强度和断裂韧性高的碳化钽.碳化钽颗粒直径小于3μm,组成晶粒为0.5～1μm,填充到双层钢管进行爆炸处理.在钢管的底部发现碳化钽试样几乎达到理论密度,但是该区域裂纹较多,硬度测得为15 GPa,和文献报道的碳化钽理论硬度相同.在钢管的中部的试样密度为理论密度的85%,这个区域没有发现裂纹.之后的旨在提高试样密度热处理中,发现了其烧结特征发生改善.经分析是因为爆炸使碳化钽粉末的颗粒内部产生内应力,而使其扩散激活能降低的结果.

关键词：碳化钽爆炸成形

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Mesenchymal stem cells as living anti-inflammatory therapy for COVID-19 related acute respiratory distress syndrome

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World Journal of stem Cells 2020年第10期12卷 1067-1079页

作者： Feng Lin Thomas E Ichim sandeep Pingle lawrence D Jones santosh Kesari shashaanka Ashili Research and Development CureScienceSan DiegoCA 92121United States Cancer Center John Wayne Cancer Institute and Pacific Neuroscience Institute at Providence Saint John's Health CenterSanta MonicaCA 90404United States

Coronavirus disease 2019(COVID-19),a pandemic disease caused by the severe acute respiratory syndrome coronavirus 2(sARs-CoV2),is growing at an exponential rate *** of this disease are heterogeneous;however,advanced cases often exhibit various acute respiratory distress syndrome-like symptoms,systemic inflammatory reactions,coagulopathy,and organ involvements.A common theme in advanced COVID-19 is unrestrained immune activation,classically referred to as a“cytokine storm”,as well as deficiencies in immune regulatory mechanisms such as T regulatory *** mesenchymal stem cells(MsCs)themselves are objects of cytokine regulation,they can secrete cytokines to modulate immune cells by inducing antiinflammatory regulatory Treg cells,macrophages and neutrophils;and by reducing the activation of T and B cells,dendritic and nature killer ***,they have therapeutic potential for treating severe cases of *** we discuss the unique ability of MsCs,to act as a“living antiinflammatory”,which can“rebalance”the cytokine/immune responses to restore *** also discuss current MsC trials and present different concepts for optimization of MsC therapy in patients with COVID-19 acute respiratory distress syndrome.

关键词： Mesenchymal stem cells sARs-CoV-2 COVID-19 Cytokine storm Acute respiratory distress syndrome Immunomodulation

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Demonstration of Covalent sidewall Functionalization of single Wall Carbon Nanotubes by NMR spectroscopy:side Chain Length Dependence on the Observation of the sidewall sp^(3)Carbons

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Nano Research 2008年第1期1卷 72-88页

作者： Liling Zeng lawrence B.Alemany Christopher L.Edwards Andrew R.Barron Richard E.smalley Institute for Nanoscale science and Technology and Department of Chemistry Rice UniversityHoustonTX 77005USA

Carboxylic acid-functionalized single walled carbon nanotubes(sWNTs)prepared via the reaction of an amino acid,NH2(CH2)nCO2H where n=1(glycine,GLY),5(6-aminohexanoic acid,AHA),10(11-aminoundecanoic acid,AUDA),with fl uorinated single walled carbon nanotubes(F-sWNTs)have been characterized by MAs 13C NMR *** ease of observing the aliphatic CH2 groups and the resolution of the signal are dependent on the length of the amino acid’s aliphatic *** have proposed that where substituent chains are short(making NMR data collection difficult)chemical modification to extend the chain length should alleviate analysis *** this regard,we have investigated the esterifi cation of the carboxylic acid *** amino acid-functionalized sWNTs were esterified with an appropriate alcohol to ensure parity of the overall substituent length,i.e.,GLY-sWNT(C1)+1-dodecanol(C_(12))=DOD-GLY-sWNT(1),AHA-sWNT(C_(5))+1-octanol(C_(8))=OCT-AHA-sWNT(2),and AUDA-sWNT(C_(10))+1-propanol(C_(3))=PRO-AUDA-sWNT(3).The 13C NMR shift for the sp3 nitrogen-substituted carbon atoms of the sWNT sidewall is observed atδ≈75 *** the length of sWNT sidewall functional groups enhances the ability to observe the sidewall sp^(3)*** methylene carbon signal intensity is less attenuated in the dipolar dephasing spectrum of the ester-functionalized sWNTs than their associated amino acid derivatives,suggesting more motional freedom of the side chain in the solid *** confi rmation of the dipolar dephasing spectral effects was assisted by the characterization of the ester of AUDA-sWNT with 1,3-propanediol:PPD-AUDA-sWNT(4).

关键词： single walled carbon nanotube(sWNT) nuclear magnetic resonance(NMR) esterification amino acid functionalization

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Hungry and Angry society: Implications for sustainable Development in Nigeria

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Journalism and Mass Communication 2024年第2期14卷 140-154页

作者： lawrence Udisi Niger Delta University Wilberforce IslandNigeria

Hunger is a physiological need,but the production and consumption of adequate and balanced food is a function of social *** every point,social,political,and economic processes intervene,for better or(more common)for *** is one fundamental need of human beings for *** in Nigeria there is widespread food shortage and *** scholars have put forward reasons why poverty,hunger persists in the country,from the platitudes about population growth,inadequate implementation of agricultural policies,and neglect of agriculture,bad leadership,corruption,and the issue of *** is richly blessed with arable land and citizens eager to unlock its food ***,this is far from being realized as the country depends on foreign countries for food,a situation that is tragic and *** spends about$10 billion a year importing food and agricultural products,the majority of which are wheat,rice,poultry,fish,and consumer-oriented *** pressure on the exchange rate results in devaluation-triggered inflation and food costs that fly up beyond the grasp of people at the bottom of the ladder as it is now is one of the negative repercussions of high food importation *** the effects of hunger is one of this paper’s key concerns and goals,and anger crisis for achieving sustainable development in the country using the Frustration-Aggression Theory,The Relative Deprivation and Political Economy Approach as guide.

关键词： hunger and angry society poverty sustainable development frustration-aggression theory political economy

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David Hume＇s Notion of Personal Identity： Implications for Identity Construction and Affective Communal Living in Africana societies

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Journal of Philosophy study 2014年第4期4卷 266-276页

作者： lawrence Bamikole University of the West Indies

The notion of personal identity is a topic that is widely discussed in all philosophical traditions-western, African, Asian, and Caribbean. The thread that runs through the different conceptions of personal identity is that the notion is linked with self-consciousness, whether in the metaphysical, epistemological, religious, or social contexts. In this paper, I shall focus attention on Hume＇s conception of personal identity drawing from it, and certain implications for affective communal life in Africana societies. It is a common knowledge among philosophers that Hume denies the ontological and independent existence of the self. For Hume, the self is a bundle of perception. However, in another section of the Treatise of Human Nature, Hume examines the development of what could be considered as self, placing it in a broad social context in which mirroring fellow minds have a critical role. What is significant in Hume＇s conception of personal identity is that the self is the locus of multifarious experiences and the social context in which it is placed enables us to relate the self to affective and relational construction of identity. It is then argued that this conception of identity can be used to stress the need for affection, love, compassion, sympathy, and empathy among persons, which in turn can promote societal transformation in Africana societies.

关键词： David Hume personal identity affective community sympathy and empathy Africana societies

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TAAPP: Tiling Array Analysis Pipeline for Prokaryotes

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Genomics, Proteomics & Bioinformatics 2011年第1期9卷 56-62页

作者： Ranjit Kumar shane C. Burgess Mark L. lawrence Bindu Nanduri College of Veterinary Medicine Mississippi State University Mississippi 39762 USA Institute for Genomics Biocomputing and Biotechnology Mississippi State University Mississippi 39762 USA Mississippi Agriculture and Forestry Experiment station Mississippi State University Mississippi 39762 USA

High-density tiling arrays provide closer view of transcription than regular microarrays and can also be used for annotating functional elements in genomes. The identified transcripts usually have a complex overlapping architecture when compared to the existing genome annotation. Therefore, there is a need for customized tiling array data analysis tools. since most of the initial tiling arrays were conducted in eukaryotes, data analysis methods are well suited for eukaryofic genomes. For using whole-genome tiling arrays to identify previously unknown transcriptional elements like small RNA and antisense RNA in prokaryotes, existing data analysis tools need to be tailored for prokaryotic genome architecture. Furthermore, automation of such custom data analysis workflow is necessary for biologists to apply this powerful platform for knowledge discovery. Here we describe TAAPP, a web-based package that consists of two modules for prokaryotic tiling array data analysis. The transcript generation module works on normalized data to generate transcriptionally active regions （TARs）. The feature extraction and annotation module then maps TARs to existing genome annotation. This module further categorizes the transcription profile into potential novel non-coding RNA, antisense RNA, gene expression and operon structures. The implemented workflow is microarray platform independent and is presented as a web-based service. The web interface is freely available for acedemic use at http：//***/TAAPP-HTML/.

关键词： transcriptomics small RNA operon prokaryotes tiling arrays

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Microstructure and mechanical properties of Ti-6Al-4V-5% hydroxyapatite composite fabricated using electron beam powder bed fusion

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Journal of Materials science & Technology 2019年第2期35卷 309-321页

作者： César A.Terrazas lawrence E.Murr Diego Bermudez Edel Arrieta David A.Roberson Ryan B.Wicker W.M.Keck Center for 3D Innovation The University of Texas at El PasoEl PasoTX 79968USA Department of Mechanical Engineering The University of Texas at El PasoTX 79968USA Department of Metallurgical Materials and Biomedical EngineeringThe University of Texas at El PasoTX 79968USA

A novel, Ti-6 Al-4 V(Ti64)/Hydroxyapatite(HA at 5% by weight concentration) metal/ceramic composite has been fabricated using electron beam powder bed fusion(EPBF) additive manufacturing(AM): specifically, the commercial electron beam melting(EBM?) process. In addition to solid Ti64 and Ti64/5% HA samples, four different unit cell(model) open-cellular mesh structures for the Ti64/5% HA composite were fabricated having densities ranging from 0.68 to 1.12 g/cm^3, and corresponding Young's moduli ranging from 2.9 to 8.0 GPa, and compressive strengths ranging from ~3 to 11 MPa. The solid Ti64/5%HA composite exhibited an optimal tensile strength of 123 MPa, and elongation of 5.5% in contrast to a maximum compressive strength of 875 MPa. Both the solid composite and mesh samples deformed primarily by brittle deformation, with the mesh samples exhibiting erratic, brittle crushing. solid, EPBF-fabricated Ti64 samples had a Vickers microindentation hardness of 4.1 GPa while the Ti64/5%HA solid composite exhibited a Vickers microindentation hardness of 6.8 GPa. The lowest density Ti64/5%HA composite mesh strut sections had a Vickers microindentation hardness of 7.1 GPa. Optical metallography(OM) and scanning electron microscopy(sEM) analysis showed the HA dispersoids to be highly segregated along domain or grain boundaries, but homogeneously distributed along alpha(hcp) platelet boundaries within these domains in the Ti64 matrix for both the solid and mesh composites. The alpha platelet width varied from ~5 μm in the EPBF-fabricated Ti64 to ~1.1 m for the Ti64/5%HA mesh strut. The precursor HA powder diameter averaged 5 μm, in contrast to the dispersed HA particle diameters in the Ti64/5%HA composite which averaged 0.5 m. This work highlights the use of EPBF AM as a novel process for fabrication of a true composite structure, consisting of a Ti64 matrix and interspersed and exposed HA domains, which to the authors' knowledge has not been reported before. The results also illu

关键词： Hydroxyapatite (HA) Metal-matrix ceramic composites Open-cellular (mesh) structures Electron-beam powder bed fusion (EPBF) Additive manufacturing (AM) Mechanical properties Microstructure characterization

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