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Determining minimum sample size for the conditioned Latin hypercube sampling algorithm

Pedosphere 2024年第3期34卷 530-539页

作者： Daniel D.SAURETTE Asim BISWAS richard j.heck Adam W.GILLESPIE Aaron A.BERG School of Environmental Sciences University of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada) Ontario Ministry of Agriculture Food and Rural Affairs1 Stone Rd WestGuelph ON N1G 2Y4(Canada) Geography Environment&GeomaticsUniversity of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada)

In digital soil mapping(DSM),a fundamental assumption is that the spatial variability of the target variable can be explained by the predictors or environmental *** to adequately sample the predictors have been well documented,with the conditioned Latin hypercube sampling(cLHS)algorithm receiving the most attention in the DSM *** advances in sampling design,a critical gap remains in determining the number of samples required for DSM *** propose a simple workflow and function coded in R language to determine the minimum sample size for the cLHS algorithm based on histograms of the predictor variables using the Freedman-Diaconis rule for determining optimal bin *** preprocessing was included to correct for multimodal and non-normally distributed data,as these can affect sample size determination from the *** on a user-selected quantile range(QR)for the sample plan,the densities of the histogram bins at the upper and lower bounds of the QR were used as a scaling factor to determine minimum sample *** technique was applied to a field-scale set of environmental covariates for a well-sampled agricultural study site near Guelph,Ontario,Canada,and tested across a range of *** results showed increasing minimum sample size with an increase in the QR *** sample size increased from 44 to 83 when the QR increased from 50% to 95% and then increased exponentially to 194 for the 99%*** technique provides an estimate of minimum sample size that can be used as an input to the cLHS algorithm.

关键词： bin width digital soil mapping normal distribution quantile range sampling design

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Object-Based Method Outperforms Per-Pixel Method for Land Cover Classification in a Protected Area of the Brazilian Atlantic Rainforest Region

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Pedosphere 2013年第3期23卷 290-297页

作者： T.RITTL M.COOPER R.j.heck M.V.R.BALLESTER Department of Soil Quality University of Wageningen Department of Soil Science University of So Paulo School of Environmental Sciences University of Guelph Center for Nuclear Energy in Agriculture (CENA) University of So Paulo

Conventional image classification based on pixels hinders the possibilities to obtain information contained in images, while modern object-based classification methods increase the acquisition of information about the object and the context in which it is inserted in the image. The objective of this study was to investigate the performance of different classification methods for land cover mapping in the vicinity of the Alto Ribeira Tourist State Park, a Brazilian Atlantic rainforest area. Two classification methods were tested, including i） a hybrid per-pixel classification using the image processing software ERDAS Imagine version 9.1 and ii） an object-based classification using the software eCognition version 5. In the first method, six different classes were established, while in the second method, another two classes were established in addition to the six classes in the first method. Accuracy assessment of the classification results presented showed that the object-based classification with a Kappa index value of 0.8687 outperformed the per-pixel classification with a Kappa index value of 0.2224. Application of the user＇s knowledge during the object-based classification process achieved the desired quality; therefore, the use of inter-relationships between objects, superelasses, subclasses, and neighboring classes were critical to improving the efficiency of land cover classification.

关键词： accuracy assessment image classification Kappa index user's knowledge

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Microbial responses to combined oxidation and catalysis treatment of 1,4-dioxane and co-contaminants in groundwater and soil

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Frontiers of Environmental Science & Engineering 2018年第5期12卷 168-180页

作者： Yu Miao Nicholas W.johnson Kimberly heck Sujin Guo Camilah D.Powell Thien Phan Phillip B.Gedalanga David T.Adamson Charles j.Newell Michael S.Wong Shaily Mahendra Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095USA Department of Chemical and Biomolecular Engineering Rice UniversityHoustonTX 77005USA Department of Health Science California State UniversityFullertonCA 92834USA GSI Environmental Inc. HoustonTX 77098USA

Post-treatment impacts of a novel combined hydrogen peroxide(H2O_(2))oxidation and WOx/ZrO_(2) catalysis used for the removal of 1,4-dioxane and chlorinated volatile organic compound(CVOC)contaminants were investigated in soil and groundwater microbial *** treatment train removed~90%1,4-dioxane regardless of initial concentrations of 1,4-dioxane and *** Illumina Miseq platform and bioinformatics were used to study the changes to microbial community *** approach determined that dynamic shifts of microbiomes were associated with conditions specific to treatments as well as 1,4-dioxane and CVOCs *** biodiversity was observed to decrease only after oxidation under conditions that included high levels of 1,4-dioxane and CVOCs,but increased when 1,4-dioxane was present without ***_(x)/ZrO_(2) catalysis reduced biodiversity across all *** classification demonstrated oxidative tolerance for members of the genera Massilia and Rhodococcus,while catalyst tolerance was observed for members of the genera Sphingomonas and *** discriminant analysis effect size was a useful statistical tool to highlight representative microbes,while the multidimensional analysis elucidated the separation of microbiomes under the low 1,4-dioxane-only condition from all other conditions containing CVOCs,as well as the differences of microbial population among original,post-oxidation,and post-catalysis *** results of this study enhance our understanding of microbial community responses to a promising chemical treatment train,and the metagenomic analysis will help practitioners predict the microbial community status during the post-treatment period,which may have consequences for long-term management strategies that include additional biodegradation treatment or natural attenuation.

关键词： Coupled treatments Chlorinated solvents Diethylene ether Biological diversity Microbial populations Biomarkers

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Bacterial Vector-Borne Plant Diseases:Unanswered Questions and Future Directions

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Molecular Plant 2020年第10期13卷 1379-1393页

作者： Weijie Huang Paola Reyes-Caldas Marina Mann Shirin Seifbarghi Alexandra Kahn Rodrigo P.P.Almeida Laure Béven Michelle heck Saskia A.Hogenhout Gitta Coaker Department of Crop Genetics John Innes CentreNorwich Research ParkNorwich NR47UHUK Department of Plant Pathology University of CaliforniaDavisCA95616USA Department of Plant Pathology and Plant-Microbe Biology Cornell UniversityIthacaNY 14853USA Department of Environmental Science Policy and ManagementUniversity of CaliforniaBerkeleyCA 94720USA UMR 1332 Biologie du Fruit et Pathologie Univ.BordeauxINRAEVillenave d'Ornon 33882 France Boyce Thompson Institute IthacaNY 14853USA Emerging Pests and Pathogens Research Unit Robert W.Holley CenterUSDA ARSIthacaNY 14853USA School of Environmental Sciences University of East AngliaNorwich Research ParkNorwich NR47T JUK

Vector-borne plant diseases have significant ecological and economic impacts,affecting farm profitability and forest composition throughout the *** vector-borne pathogens have evolved sophisticated strategies to interact with their hemipteran insect vectors and plant *** pathogens reside in plant vascular tissue,and their study represents an excellent opportunity to uncover novel biological mechanisms regulating intracellular pathogenesis and to contribute to the control of some of the world's most invasive emerging *** this perspective,we highlight recent advances and major unanswered questions in the realm of bacterial vector-borne disease,focusing on liberibacters,phytoplasmas,spiroplasmas,and Xylella fastidiosa.

关键词： liberibacter phytoplasma spiroplasma Xylella fastidiosa vector-borne disease effector plant immunity

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Identification of common and distinct origins of human serum and breastmilk IgA1 by mass spectrometry-based clonal profiling

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Cellular & Molecular Immunology 2023年第1期20卷 26-37页

作者： Kelly A.Dingess Max Hoek Danique M.Hvan Rijswijk Sem Tamara Maurits Aden Boer Tim Veth Mirjam j.A.Damen Arjan Barendregt Michelle Romijn Hannah G.juncker Britt jvan Keulen Gestur Vidarsson johannes Bvan Goudoever Albert Bondt Albert j.R.heck Biomolecular Mass Spectrometry and Proteomics Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical SciencesUniversity of UtrechtPadualaan 8Utrecht 3584 CHThe Netherlands Netherlands Proteomics Center Padualaan 8Utrecht 3584 CHThe Netherlands Amsterdam UMC Vrije UniversiteitUniversity of AmsterdamEmma Children’s HospitalAmsterdam Reproduction&Development Research InstituteDepartment of PediatricsAmsterdamthe Netherlands Department of Experimental Immunohematology Sanquin Research and Landsteiner LaboratoryAmsterdam UMCUniversity of AmsterdamAmsterdamNetherlands

The most abundant immunoglobulin present in the human body is IgA. It has the highest concentrations at the mucosal lining and in biofluids such as milk and is the second most abundant class of antibodies in serum. We assessed the structural diversity and clonal repertoire of IgA1-containing molecular assemblies longitudinally in human serum and milk from three donors using a mass spectrometry-based approach. IgA-containing molecules purified from serum or milk were assessed by the release and subsequent analysis of their Fab fragments. Our data revealed that serum IgA1 consists of two distinct structural populations, namely monomeric IgA1 (∼80%) and dimeric joining (j-) chain coupled IgA1 (∼20%). Also, we confirmed that IgA1 in milk is present solely as secretory (S)IgA, consisting of two (∼50%), three (∼33%) or four (∼17%) IgA1 molecules assembled with a j-chain and secretory component (SC). Interestingly, the serum and milk IgA1-Fab repertoires were distinct between monomeric, and j-chain coupled dimeric IgA1. The serum dimeric j-chain coupled IgA1 repertoire contained several abundant clones also observed in the milk IgA1 repertoire. The latter repertoire had little to no overlap with the serum monomeric IgA1 repertoire. This suggests that human IgA1s have (at least) two distinct origins;one of these produces dimeric j-chain coupled IgA1 molecules, shared in human serum and milk, and another produces monomeric IgA1 ending up exclusively in serum.

关键词： Antigen binding fragment Immunoglobulin A1 Clonal repertoires human milk Serum

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Characteristics of termite mounds and associated Acrisols in the coastal savanna zone of Ghana and impact on hydraulic conductivity

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Natural Science 2012年第7期4卷 423-437页

作者： Gabriel N. N. Dowuona Pearl Atwere W. Dubbin Prosper M. Nude Baba E. Mutala Eric K. Nartey richard j. heck Department of Earth Science University of Ghana Legon Ghana Department of Soil Science School of Agriculture University of Ghana Legon Ghana Natural History Museum Mineralogy Department London SW7 5BD U.K School of Environmental Sciences University of Guelph Guelph Ontario Canada

Characteristics of termite mounds and associated Rhodic Acrisol and Haplic Acrisol in the coastal savanna zone of Ghana and their impact on hydraulic conductivity were assessed. The texture of the mounds was sandy clay in contrast to the sandy clay loam of the surface soils. Translocation of fine to medium sized soil materials influenced the relatively higher bulk density (>1.60 Mg/m3) and contents of organic carbon, nitrogen and exchangeable bases in the mounds. Kaolinite was the dominant clay mineral with pH values generally below 5.3 in all the soils reflecting the weathered tropical soil environment. Dispersion ratio values, which were 0.5 for the surface soils, indicated greater stability of the mound due to aggregate cementing action by the termites. Estimated mound density was about 120 mounds per ha, which tied in with known groundwater reserves at the study sites. Majority of the mounds exhibited a cone-shaped morphology with heights varying between 3.05-4.00 m in the Rhodic Acrisol and 2.05-4.20 m in the Haplic Acrisol with corresponding estimated total mass of 96,361 kg and 54,910 kg per 1000 m2 land area. These estimates represented a large amount of material relative to the 25,000-26,000 kg of surface soil material within the same unit area. The K in the surface soils ranged from 3.3 x 10-5 to 5.0 x 10-5 m/s while the value for the mound was ≤0.5 x 10-5 m/s. Lower porosity, θ;the effect was more pronounced when the mound was applied on the soil surface. Improvement in water retention and nutrient availability to plants and prevention of leaching to avoid groundwater contamination are some of the positive attributes of this study.

关键词： Aggregate Stability Clay Mineralogy Dispersion Ratio Hydraulic Conductivity Mound Morphology Termite Mounds

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Low phase noise hybrid silicon mode-locked lasers

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Frontiers of Optoelectronics 2014年第3期7卷 265-276页

作者： Sudharsanan SRINIVASAN Michael DAVENPORT Martijn j. R. heck john HUTCHINSON Erik NORBERG Gregory FISH john BOWERS Department of Electrical and Computer Engineering University of California Santa Barbara CA 93106 USA Department of Engineering Aarhus University Aarhus Denmark Aurrion Inc. Goleta CA 93117 USA

In this paper, we review recent results on hybrid silicon mode-locked lasers with a focus on low phase noise optical pulse generation. Taking a high level design approach to lowering phase noise, we show the need for long on-chip optical delay lines for mode-locked lasers to reach and overcome material limits. Key results include demonstration of the longest （cavity length 9 cm） integrated on-chip mode locked laser, 14 dB reduction of Lorentzian noise on a 20 GHz radio-frequency （RF） signal, and greater than 55 dB optical supermode noise suppres- sion using harmonically mode locked long cavity laser, 10 GHz passively mode locked laser with 15 kHz linewidth using on-chip all optical feedback stabilization.

关键词： optoelectronic devices mode-locked lasers semiconductor lasers

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大型氢气生产工艺的改进

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天然气化工(C1化学与化工) 1979年第1期 67-71页

作者： j.L.heck T.johansen 曾阳

多床变压吸附（PSA）能使单系列装置的氢气产量增加到4500万标准英尺3/天,而氢气回收率超过较早的四床设计的10%。将多床PSA装置和蒸汽转化炉恰当结合,现能在大型装置中生产出超纯氢气,其成本低于由两段变换炉、后接液体洗涤脱除CO2和... 详细信息

多床变压吸附（PSA）能使单系列装置的氢气产量增加到4500万标准英尺3/天,而氢气回收率超过较早的四床设计的10%。将多床PSA装置和蒸汽转化炉恰当结合,现能在大型装置中生产出超纯氢气,其成本低于由两段变换炉、后接液体洗涤脱除CO2和甲烷化等过

关键词：氢气 PSA 工业气体制氢装置转化炉

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大型制氢装置的工艺改进(PSA工艺)——与常规流程相比减少能耗经济节约

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齐鲁石油化工 1988年第5期 67-71页

作者： j.L.heck T.johansen 李东梅

多床层变压吸附(PSA)单系列氢气生产装置,其处理能力允许达到4500万标英尺~3/天(5万标米~3/时),同时氢气的回收率比早期设计的4床层工艺增加10％。多床PSA工艺与蒸汽转化法恰当的结合,可以在大型装置上。生产超高纯度的氧气。这比采用... 详细信息

多床层变压吸附(PSA)单系列氢气生产装置,其处理能力允许达到4500万标英尺~3/天(5万标米~3/时),同时氢气的回收率比早期设计的4床层工艺增加10％。多床PSA工艺与蒸汽转化法恰当的结合,可以在大型装置上。生产超高纯度的氧气。这比采用常规的蒸汽转化、二级变换、溶液脱二氧化碳和甲烷化流程来生

关键词：制氢装置 PSA 工艺条件氢气提纯变压吸附脱二氧化碳转化炉甲烷化床层转化气

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N<sup>ω</sup>-Nitro-N<sup>ω’</sup>-Substituted Guanidines: A Simple Class of Nitric Oxide Synthase Inhibitors

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Modern Research in Inflammation 2014年第2期3卷 48-58页

作者： Christophe D. Guillon David D. Wisnoski jaya Saxena Ned D. Heindel Diane E. heck Donald j. Wolff jeffrey D. Laskin Department of Chemistry Lehigh University Bethlehem USA Department of Environmental and Occupational Medicine Rutgers University—Robert Wood Johnson Medical School Piscataway USA Department of Environmental Health Science New York Medical College Valhalla USA Department of Pharmacology Rutgers University—Robert Wood Johnson Medical School Piscataway USA

A series of Nω-nitro-Nω’-substituted guanidines has been prepared as potential inhibitors of the human Nitric Oxide Synthase (NOS) isoforms. The reported utility of amino-guanidine and nitroarginine in iNOS inhibition points to a potential similar utility for analogs of nitro-guanidine. The compound library was tested against the three isoforms of Nitric Oxide Synthase (eNOS, iNOS and nNOS). Several candidates showed excellent activity and good selectivity for nNOS. One particular compound even demonstrated good selectivity for iNOS. The potential usefulness of such selective inhibitors is discussed.

关键词： Nitro-Guanidines Nitric Oxide Synthase (NOS) Isoforms Selective Inhibitors

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