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Comparison of sampling designs for calibrating digital soil maps at multiple depths

Pedosphere 2022年第4期32卷 588-601页

作者： Yakun ZHANG daniel d.SAURETTE Tahmid Huq EASHER Wenjun JI Viacheslav I.AdAMCHUK Asim BISWAS University of Wisconsin-Madison Department of Soil ScienceFD Hole Soils Lab1525 Observatory DriveMadison WI 53706USA School of Environmental Sciences University of Guelph50 Stone Road EastGuelph ON N1G 2W1Canada College of Land Science and Technology China Agricultural UniversityBeijing 100083China department of Bioresource Engineering McGill University21111 Lakeshore RoadSte-Anne-de-Bellevue QC H9X 3V9Canada

digital soil mapping (dSM) aims to produce detailed maps of soil properties or soil classes to improve agricultural management and soil quality assessment. Optimized sampling design can reduce the substantial costs and efforts associated with sampling, profile description, and laboratory analysis. The purpose of this study was to compare common sampling designs for dSM, including grid sampling (GS), grid random sampling (GRS), stratified random sampling (StRS), and conditioned Latin hypercube sampling (cLHS). In an agricultural field (11 ha) in Quebec, Canada, a total of unique 118 locations were selected using each of the four sampling designs (45 locations each), and additional 30 sample locations were selected as an independent testing dataset (evaluation dataset). Soil visible near-infrared (Vis-NIR) spectra were collected in situ at the 148 locations (1 m depth), and soil cores were collected from a subset of 32 locations and subdivided at 10-cm depth intervals, totaling 251 samples. The Cubist model was used to elucidate the relationship between Vis-NIR spectra and soil properties (soil organic matter (SOM) and clay), which was then used to predict the soil properties at all 148 sample locations. digital maps of soil properties at multiple depths for the entire field (148 sample locations) were prepared using a quantile random forest model to obtain complete model maps (CM-maps). Soil properties were also mapped using the samples from each of the 45 locations for each sampling design to obtain sampling design maps (Sd-maps). The Sd-maps were evaluated using the independent testing dataset (30 sample locations), and the spatial distribution and model uncertainty of each Sd-map were compared with those of the corresponding CM-map. The spatial and feature space coverage were compared across the four sampling designs. The results showed that GS resulted in the most even spatial coverage, cLHS resulted in the best coverage of the feature space, and GS and cLHS resu

关键词： 3d digital soil mapping conditioned Latin hypercube sampling grid sampling quantile random forest model stratified random sampling

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determining minimum sample size for the conditioned Latin hypercube sampling algorithm

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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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Analysis of geo-spatiotemporal data using machine learning algorithms and reliability enhancement for urbanization decision support

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International Journal of digital Earth 2020年第12期13卷 1717-1732页

作者： Kwame O.Hackman Xuecao Li daniel Asenso-Gyambibi Emmanuella A.Asamoah Isaac.d.Nelson data Management department WASCAL Competence CenterOuagadougouBurkina Faso department of Geological and Atmospheric Sciences Iowa State UniversityAmesUSA department of Environmental Management University of Energy and Natural ResourcesSunyaniGhana Building and Road Research Institute(BRRI) Council for Scientific and Industrial Research(CSIR)KumasiGhana

We present systematic analyses of the temporal dynamics of the growth of Kumasi,the fastest growing city in Ghana using 20-year Landsat timeseries data from 2000 to 2020(with 1986 Landsat image as a baseline).Two classification algorithms–random forest(RF)and support vector machines(SVM)–were used to produce binary(built-up/non-built up)maps for all years within the temporal *** further implemented an anomaly detection and temporal consistency algorithm followed by a changing logic to correct the classification anomalies due to image contamination from the cloud and other *** mean overall accuracies obtained for RF and SVM were 94.9%(kappa=0.90)and 95.5%(kappa=0.91),*** results reveal that the mean builtup area percentages of the metropolis are approximately 74,65,47,and 23 for the years 2020,2010,2000,and 1986,respectively,representing a mean annual change of 3.5%over the 34 *** the present lack of labeled data in Ghana for in-depth analyses of the evolution of land use,we believe that this study serves as an initial attempt to a better understanding of the effects of increasing anthropogenic activities due to urbanization,on human and environment health.

关键词： Urbanization Kumasi support vector machine random forest Landsat

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Reproduction and beyond,kisspeptin in ruminants

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Journal of Animal Science and Biotechnology 2015年第3期6卷 264-268页

作者： Joseph A.daniel Chad d.Foradori Brian K.Whitlock James L.Sartin department of Animal Science Berry College department of Anatomy Physiology & PharmacologyAuburn University department of Large Animal Clinical Sciences University of Tennessee

Kisspeptin （Kp） is synthesized in the arcuate nucleus and preoptic area of the hypothalamus and is a regulator of gonadotropin releasing hormone in the hypothalamus. In addition, Kp may regulate additional functions such as increased neuropeptide Y gene expression and reduced proopiomelanocortin （POMC） gene expression in sheep. Other studies have found a role for Kp to release growth hormone （GH）, prolactin and luteinizing hormone （LH） from cattle, rat and monkey pituitary cells. Intravenous injection of Kp stimulated release LH, GH, prolactin and follicle stimulating hormone in some experiments in cattle and sheep, but other studies have failed to find an effect of peripheral injection of Kp on GH release. Recent studies indicate that Kp can stimulate GH release after intracerebroventricular injection in sheep at doses that do not release GH after intravenous injection. These studies suggest that Kp may have a role in regulation of both reproduction and metabolism in sheep. Since GH plays a role in luteal development, it is tempting to speculate that the ability of Kp to release GH and LH is related to normal control of reproduction.

关键词： Growth hormone Leptin Luteinizing Neuropeptide Y POMC

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Recurrence rates after endoscopic resection of large colorectal polyps:A systematic review and meta-analysis

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World Journal of Gastroenterology 2022年第29期28卷 4007-4018页

作者： Carola Rotermund Roupen djinbachian Mahsa Taghiakbari Markus d Enderle Axel Eickhoff daniel von Renteln Research and Basic Technologies ERBE Elektromedizin GmbHTuebingen 72072Germany division of Internal Medicine Montreal University Hospital CenterMontreal QC H2X 3E4Canada Montreal University Hospital Research Center Montreal University Hospital CenterMontreal QC H2X 3E4Canada department of Internal Medicine II Klinikum HanauHanau 63450Germany

BACKGROUNd Complete polyp resection is the main goal of endoscopic removal of large colonic *** techniques have evolved in recent years and endoscopic submucosal dissection(ESd),endoscopic mucosal resection(EMR)with margin ablation,cold snare polypectomy(CSP),cold EMR,and underwater EMR have been ***,efficacy of these techniques with regard to local recurrence rates(LRRs)vs traditional hot snare polypectomy and standard EMR remains *** To analyze LRR of large colonic polyps in a systematic review and *** MEdLINE,EMBASE,EBM Reviews,and CINAHL were searched for prospective studies reporting LRR or incomplete resection rate(IRR)after colonic polypectomy of polyps≥10 mm,published between January 2011 and July *** outcome was LRR for polyps≥10 *** Six thousand nine hundred and twenty-eight publications were identified,of which 34 prospective studies were *** for polyps≥10 mm at up to 12 mo’follow-up was 11.0%(95%CI,7.1%-14.8%;15 studies;4904 polyps).ESd(1.7%;95%CI,0%-3.4%;3 studies,221 polyps)and endoscopic mucosal resection with margin ablation(3.3%;95%CI,2.2%-4.5%;2 studies,947 polyps)significantly reduced LRR vs standard EMR without(15.2%;95%CI,12.5%-18.0%;4 studies,650 polyps)or with unsystematic margin ablation(16.5%;95%CI,15.2%-17.8%;6 studies,3031 polyps).CONCLUSION LRR is significantly lower after ESd or EMR with routine margin ablation;thus,these techniques should be considered standard for endoscopic removal of large colorectal *** techniques,such as CSP,cold EMR,and underwater EMR require further evaluation in prospective studies before their routine implementation in clinical practice can be recommended.

关键词： Colonoscopy Adenoma Polyp Endoscopic mucosal resection Colorectal cancer

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Male and female meadow voles Microtus pennsylvanicus respond differently to scent marks from the top- middle-, and bottom-scent donors of an over-mark

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Current Zoology 2011年第4期57卷 441-448页

作者： Michael H. FERKIN Nicholas J. HOBBS Benjamin d. FERKIN Adam C.FERKIN daniel A. FERKIN department of Biological Sciences The University of Memphis Ellington Hall Memphis TN 38152 USA

Previous studies have shown that individuals responded preferentially to the mark of the top-scent donor relative to that of the bottom-scent donor of an over-mark. However, terrestrial mammals are likely to encounter over-marks consisting of the scent marks of more than two same-sex conspecifics in the intersections of runways, near the nests of sexually receptive female conspecifics, and inside and along the borders of the territories of conspecifics. We determined how meadow voles, Microtus pennsylvanicus, respond to the marks of the top-, middle-, and bottom-scent donors of an over-mark. We tested the hypothesis that voles exposed to an over-mark will respond preferentially to the scent marks that were deposited more recently, the scent marks that were on top or near the top of the over-mark, compared to the scent marks that were deposited earlier or near the bot- tom of the over-mark. Voles spent more time investigating the mark of the top-scent donor than that of the either the middle- or bottom-scent donor. However, males but not female voles spent more time investigating the middle-scent mark than the bot- tom-scent mark. We also tested the hypothesis that voles evaluate and respond to over-marks differently from single scent marks. Voles spent more time investigating the marks of the top-, middle-, and bottom-scent donors compared to scent marks that were not part of the over-mark. Voles can distinguish among the overlapping scent marks of three scent donors and sex differences exist in the values they appear to attach to each of these scent marks [Current Zoology 57 （4）： 441-448, 2011 ].

关键词： Over-marks Voles Scent marks Olfactory communication

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Gastroesophageal cancer and retroperitoneal fibrosis: Two case reports and review of the literature

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World Journal of Gastrointestinal Oncology 2013年第3期5卷 68-70页

作者： Renata d'Alpino Peixoto Jasem Al-Barrak Howard Lim daniel Renouf department of Medical Oncology BC Cancer Agency

Retroperitoneal fibrosis secondary to malignant disease is a rare condition associated with a dismal prognosis. We herein present the first ever reported case of ret-roperitoneal fibrosis related to esophageal adenocarcinoma in a 63-year-old patient who developed bilateral ureteral obstruction due to extensive retroperitoneal fibrosis 18 mo after having completed neoadjuvant chemoradation followed by surgery for a pT3N0 ad-enocarcinoma of the distal esophagus. We also report the case of a previously healthy woman who presented with bilateral ureteral obstruction and diffuse narrowing of the common biliary duct and was found to have extensive retroperitoneal fibrosis as a consequence of metastatic gastric adenocarcinoma. Both patients had poor performance status and were unsuitable for pallia-tive chemotherapy. This paper shows that urinary and biliary obstructive symptoms might represent retroperi-toneal fibrosis as a consequence of gastroesophageal malignancy.

关键词： Gastric cancer Esophageal cancer Retro-peritoneal fibrosis

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Knowledge of radiation exposure associated with common trauma imaging modalities among orthopaedic surgeons,emergency medicine physicians,and general surgeons in the United States

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World Journal of Emergency Medicine 2023年第4期14卷 294-301页

作者： Fady Y.Hijji Andrew d.Schneider Matthew d.Thomas Joseph G.Lyons daniel d.Bohl Jennifer L.Jerele Michael J.Prayson department of Orthopaedic Surgery Wright State University Boonshoft School of MedicineDayton OH 45409USA department of Orthopaedic Surgery Rush University Medical CenterChicago IL 60612USA

BACKGROUNd:Few contemporary studies have assessed physicians’knowledge of radiation exposure associated with common imaging studies,especially in trauma *** purpose of this study was to assess the knowledge of physicians involved in caring for trauma patients regarding the effective radiation doses of musculoskeletal(MSK)imaging studies routinely utilized in the trauma ***:An electronic survey was distributed to United States orthopaedic surgery,general surgery,and emergency medicine(EM)residency *** were asked to estimate the radiation dose for common imaging modalities of the pelvis,lumbar spine,and lower extremity,in terms of chest X-ray(CXR)*** estimates were compared to the true effective radiation ***,participants were asked to report the frequency of discussing radiation risk with ***:A total of 218 physicians completed the survey;102(46.8%)were EM physicians,88(40.4%)wereorthopaedicsurgeons,and28(12.8%)*** underestimated the effective radiation doses of nearly all imaging modalities,most notably for pelvic computed tomaography(CT)(median 50 CXR estimation vs.162 CXR actual)and lumbar CT(median 50 CXR estimation vs.638 CXR actual).There was no difference between physician specialties regarding estimation accuracy(P=0.133).Physicians who regularly discussed radiation risks with patients more accurately estimated radiation exposure(P=0.007).CONCLUSION:The knowledge among orthopaedic and general surgeons and EM physicians regarding the radiation exposure associated with common MSK trauma imaging is *** investigation with larger scale studies is warranted,and additional education in this area may improve care.

关键词： Radiation dosage Radiation exposure Radiation protection X-ray Emergency department

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Laboratory evaluation of the GreenSeeker^(TM) handheld optical sensor to variations in orientation and height above canopy

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International Journal of Agricultural and Biological Engineering 2012年第1期5卷 43-47页

作者： daniel E Martin Juan d Lopez Jr Yubin Lan USdA-ARS Southern Plains Agricultural Research CenterCollege StationTexas 77845USA

Handheld optical sensors recently have been introduced to the agricultural *** handheld sensors are able to provide operators with Normalized difference Vegetative Index(NdVI)data when cloud cover prevents acquisition of satellite or aerial *** research addressed the sensitivity of the GreenSeeker handheld optical sensor to changes in orientation and height above a ryegrass *** boxes were oriented both parallel and perpendicular to the light beam from the sensor head and heights of 30.5 cm(12”),61.0 cm(24”),91.5 cm(36”),122 cm(48”)and 152 cm(60”)were *** indicated that the sensor was highly sensitive(Pd orientation of the sensor relative to the *** should follow manufacturer’s recommendations on operating height range of 81-122 cm and orient the sensor head in-line with the target to obtain maximum signal response.

关键词： remote sensing NdVI GreenSeeker handheld optical sensor spectral reflectance

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Process control factors for continuous microbial perchlorate reduction in the presence of zero-valent iron

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Frontiers of Environmental Science & Engineering 2014年第3期8卷 386-393页

作者： Robert d. ARTHUR Jagadish TORLAPATI Kyung-Hee SHIN daniel K. CHA Yeomin YOON Ahjeong SON department of Civil Engineering Auburn University Auburn AL 36849 USA Korea Environment Institute Seoul 122-706 Republic of Korea department of Civil and Environmental Engineering University of Delaware Newark DE 19716 USA department of Civil and Environmental Engineering University of South Carolina Columbia SC 29208 USA department of Environmental Science and Engineering Ewha Womans University Seoul 120-750 Korea

Process control parameters influencing microbial perchlorate reduction via a flow-through zero-valent iron （ZVI） column reactor were investigated in order to optimize perchlorate removal from water. Mixed perchlorate reducers were obtained from a wastewater treatment plant and inoculated into the reactor without further acclimation. Examined parameters included hydraulic residence time （HRT）, pH, nutrients requirement, and perchlorate reduction kinetics. The minimum HRT for the system was concluded to be 8 hr. The removal efficiency of 10 mg. L-1 influent perchlorate concentration was reduced by 20%-80% without control to the neutral pH （HRT = 8 hr）. Therefore pH was determined to be an important parameter for microbial perchlorate reduction. Furthermore, a viable alternative to pH buffer was discussed. The microbial perchlorate reduction followed the first order kinetics, with a rate constant （K） of 0.761 hr-1. The results from this study will contribute to the implementation of a safe, cost effective, and efficient system for perchlorate reduction to below regulated levels.

关键词： perchlorate zero-valent iron (ZVI) microbial reduction hydrogen

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