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Assessing the impact of conceptual mineral systems uncertainty on prospectivity predictions

Geoscience Frontiers 2022年第6期13卷 182-207页

作者： mark d lindsay Agnieszka M.Piechocka mark W Jessell Richard Scalzo Jeremie Giraud Guillaume Pirot Edward Cripps Commonwealth Scientific and Industrial Research Organisation Mineral Resources Australian Resources Research CentreWA 6151Australia Mineral Exploration Cooperative Research Centre Centre for Exploration TargetingSchool of Earth SciencesThe University of Western AustraliaPerthWA 6009Australia ARC Centre for data Analytics for Resources and Environments(dARE) Perth and SydneyAustralia University of Sydney School of Mathematics and StatisticsSydneyAustralia Universitéde Lorraine GeoRessourcesCNRS54000 NancyFrance The University of Western Australia Department of Mathematics and StatisticsPerthAustralia

The past two decades have seen a rapid adoption of artificial intelligence methods applied to mineral exploration. More recently, the easier acquisition of some types of data has inspired a broad literature that has examined many machine learning and modelling techniques that combine exploration criteria,or ’features’, to generate predictions for mineral prospectivity. Central to the design of prospectivity models is a ’mineral system’, a conceptual model describing the key geological elements that control the timing and location of economic mineralisation. The mineral systems model defines what constitutes a training set, which features represent geological evidence of mineralisation, how features are engineered and what modelling methods are used. Mineral systems are knowledge-driven conceptual models, thus all parameter choices are subject to human biases and opinion so alternative models are ***, the effect of alternative mineral systems models on prospectivity is rarely compared despite the potential to heavily influence final predictions. In this study, we focus on the effect of conceptual uncertainty on Fe ore prospectivity models in the Hamersley region, Western Australia. Four important considerations are tested.(1) Five different supergene and hypogene conceptual mineral systems models guide the inputs for five forest-based classification prospectivity models model.(2) To represent conceptual uncertainty, the predictions are then combined for prospectivity model comparison.(3)Representation of three-dimensional objects as two-dimensional features are tested to address commonly ignored thickness of geological units.(4) The training dataset is composed of known economic mineralisation sites(deposits) as ’positive’ examples, and exploration drilling data providing ’negative’sampling locations. Each of the spatial predictions are assessed using independent performance metrics common to AI-based classification methods and subjected to geological pl

关键词： Uncertainty Modelling Prospectivity Economic geology Geological plausibility Forest-based classification

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Emerging role of A-kinase anchoring protein 5 signaling in reward circuit function

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Neural Regeneration Research 2025年第10期20卷 2913-2914页

作者： William J.Flerlage mark L.dell’Acqua Brian M.Cox Fereshteh S.Nugent Uniformed Services University of the Health Sciences Department of Pharmacology and Molecular TherapeuticsBethesdaMDUSA department of Pharmacology University of Colorado School of MedicineAnschutz Medical CampusAuroraCOUSA

There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(Simmons et al.,2024).diverse sets of distinct molecular signaling pathways converge on the synapse to regulate synaptogenesis,synaptic function,and synaptic plasticity in brain regions and circuits through complex interactions organized by numerous multivalent protein scaffolds,including the family of proteins known as A-kinase anchoring proteins(AKAPs).

关键词： function supporting

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A Bayesian hierarchical model for the inference between metal grade with reduced variance:Case studies in porphyry Cu deposits

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Geoscience Frontiers 2024年第2期15卷 304-314页

作者： Yufu Niu mark lindsay Peter Coghill Richard Scalzo Lequn Zhang CSIRO Mineral Resources Lucas HeightsNew South Wales 2234Australia Mineral Exploration Cooperative Research Centre Centre for Exploration TargetingSchool of Earth ScienceThe University of Western AustraliaPerthWA 6009Australia ARC centre for data Analytics for Resources and Environments(dARE) Perth and SydneyAustralia CSIRO Mineral Resources Australian Resources Research CentreWA 6151Australia CSIRO data61 ClaytonVIC 3168Australia

Ore sorting is a preconcentration technology and can dramatically reduce energy and water usage to improve the sustainability and profitability of a mining *** porphyry Cu deposits,Cu is the primary target,with ores usually containing secondary‘pay’metals such as Au,Mo and gangue elements such as Fe and *** to sensing technology limitations,secondary and deleterious materials vary in correlation type and strength with Cu but cannot be detected simultaneously via magnetic resonance(MR)ore *** the relationships between Cu and other elemental abundances is particularly critical for mineral *** variations in metal grade relationships occur due to the transition into different geological *** raises two questions-how to define these geological domains and how the metal grade relationship is influenced by these geological *** this paper,linear relationship is assumed between Cu grade and other metal *** applies a Bayesian hierarchical(partial-pooling)model to quantify the linear relationships between Cu,Au,and Fe grades from geochemical bore core *** hierarchical model was compared with two other models-‘complete-pooling’model and‘nopooling’*** blocks were split based on spatial domain to construct hierarchical *** bore core data records metal grades measured from laboratory assay with spatial coordinates of sample *** case studies from different porphyry Cu deposits were used to evaluate the performance of the hierarchical *** chain Monte Carlo(MCMC)was used to sample the posterior *** results show that the Bayesian hierarchical model dramatically reduced the posterior predictive variance for metal grades regression compared to the no-pooling *** addition,the posterior inference in the hierarchical model is insensitive to the choice of *** data is wellrepresented in the posterior which indicates a robust *** results show that the spatial dom

关键词： Bayesian hierarchical model Porphyry Cu deposit Ore sorting Metal grade Linear regression

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Surgical treatment of Lenke 5 adolescent idiopathic scoliosis: Comparison of anterior vs posterior approach

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World Journal of Orthopedics 2016年第9期7卷 553-560页

作者： mark F Abel Anuj Singla mark A Feger lindsay d Sauer Wendy Novicoff department of Orthopedic Surgery University of Virginia

AIM To compare the posterior vs anterior approaches for fusion of Lenke 5 adolescent idiopathic scoliosis curves,matched for curve magnitude and for the distal level of fixation(dLOF) standardized to the third lumbar vertebrae(L3).METHOdS A prospectively collected multicenter database was used for this retrospective comparative study. Our dependent variables included sagittal and coronal radiographic measurements, number of fused vertebrae, estimated blood loss, length of hospitalization and SRS total and individual domain scores at the two-year follow-up. Subject demographics were similar for all group *** t-test was used to compare groups for all analyses at P d cases of Lenke 5 curves, a selective approach was used only 50% of the time in cases undergoing a posterior fusion. When comparing a posterior selective approach to an anterior selective approach,surgeons utilizing a posterior approach fused significantly more levels than surgeons using an anterior approach with no other significant differences in radiographic or SRS outcomes(Ant = 4.8 ± 1.0 levels vs post = 6.1 ± 1.0 levels, P dLOF was standardized to L3, the anterior approached provided significantly greater lumbar Cobb percent correction than the posterior approach(Ant = 69.1% ± 12.6% vs post =54.6% ± 16.4%, P = 0.004), with no other significant radiographic or SRS score differences between *** Surgeons treating Lenke 5c curves with a posterior instrumentation and fusion vs an anterior approach include more motion segments, even with a selective fusion. When controlled for the distal level of fixation,the anterior approach provides greater correction of the thoracolumbar curve.

关键词： Instrumentation Thoracolumbar curve Selective fusion

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Numerical modelling of high-temperature superconducting dynamos:A review

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Superconductivity 2023年第1期5卷 1-16页

作者： mark d Ainslie department of Engineering King’s College LondonStrandLondon WC2R 2LSUnited Kingdom

The high‐temperature superconducting(HTS)dynamo enables injection of large dC currents into a superconducting coil,without the need for thermally‐inefficient current *** of this important advantage,there is significant interest in using such technology to energise superconducting coils in superconducting rotating machines and NMR/MRI *** the extensive experimental work carried out over the past decade,there was–until very recently–considerable confusion and debate regarding the physical origin of the HTS dynamo’s dC output *** modelling has played a key role in elucidating the underlying physics of such devices and several different numerical models have now been developed as useful and cost‐effective tools to not only explain and further examine experimental results,but also optimise and improve dynamo *** review summarises all of the developments in this important area over recent years,including modelling the open‐circuit voltage behaviour in 2d and 3d,the definition of a new benchmark problem for the HTS modelling community,investigating key dynamo parameters,modelling dynamic coil charging behaviour and calculating losses.A view towards the future is provided,including the outstanding challenges and the developments required to address these.

关键词： HTS modelling HTS dynamo HTS flux pump High temperature superconductors Numerical simulation Finite‐element method

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Addressing nonresponse bias in forest inventory change estimation using response homogeneity classifications

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Forest Ecosystems 2023年第1期10卷 125-131页

作者： James A.Westfall mark d.Nelson U.S.Forest Service Northern Research StationYorkPAUSA U.S.Forest Service Northern Research StationSt.PaulMNUSA

Estimating amounts of change in forest resources over time is a key function of most national forest inventories(NFI). As this information is used broadly for many management and policy purposes, it is imperative that accurate estimations are made from the survey sample. Robust sampling designs are often used to help ensure representation of the population, but often the full sample is unrealized due to hazardous conditions or possibly lack of land access permission. Potentially, bias may be imparted to the sample if the nonresponse is nonrandom with respect to forest characteristics, which becomes more difficult to assess for change estimation methods that require measurements of the same sample plots at two points in time, i.e., remeasurement. To examine potential nonresponse bias in change estimates, two synthetic populations were constructed: 1) a typical NFI population consisting of both forest and nonforest plots, and 2) a population that mimics a large catastrophic disturbance event within a forested population. Comparisons of estimates under various nonresponse scenarios were made using a standard implementation of post-stratified estimation as well as an alternative approach that groups plots having similar response probabilities(response homogeneity). When using the post-stratified estimators, the amount of change was overestimated for the NFI population and was underestimated for the disturbance population, whereas the response homogeneity approach produced nearly unbiased estimates under the assumption of equal response probability within groups. These outcomes suggest that formal strategies may be needed to obtain accurate change estimates in the presence of nonrandom nonresponse.

关键词： disturbance Post-stratification Land use conversion Sample bias

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Sex-specific life-history strategies among immature jumping spiders:differences in body parameters and behavior

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Current Zoology 2023年第5期69卷 535-551页

作者： LászlóMezőfi Viktor markó dóraÁgnes Taranyi Gábor markó Institute of Plant Protection Hungarian University of Agriculture and Life SciencesBudapest 1118Hungary Institute of Viticulture and Enology Hungarian University of Agriculture and Life SciencesBudapest 1118Hungary

Selection forces often generate sex-specific differences in various traits closely related to *** in adult spiders(Araneae),sexes often differ in coloration,body size,antipredator,or foraging behavior,such sex-related differences are less pronounced among ***,sex-specific life-history strategies may also be adaptive for ***,we hypothesized that among spiders,immature individuals show different life-history strategies that are expressed as sex-specific differences in body parameters and behavioral features,and also in their *** used immature individuals of a protandrous jumping spider,Carrhotus xanthogramma,and examined sex-related *** results showed that males have higher mass and larger prosoma than *** were more active and more risk tolerant than *** activity increased with time,and larger males tended to capture the prey faster than small ones,while females showed no such ***,females reacted to the threatening abiotic stimuli more with the increasing number of test *** both males and females,individuals with better body conditions tended to be more risk *** showed no sex-specific differences in interindividual behavioral consistency and in intraindividual behavioral variation in the measured behavioral ***,we also found evidence for behavioral syndromes(i.e.,correlation between different behaviors),where in males,only the activity correlated with the risk-taking behavior,but in females,all the measured behavioral traits were *** present study demonstrates that *** sexes follow different life-history strategies even before attaining maturity.

关键词： activity behavioral syndrome boldness intraindividual variability repeatability sexual dimorphism

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Incorporating conceptual and interpretation uncertainty to mineral prospectivity modelling

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Geoscience Frontiers 2019年第4期10卷 1383-1396页

作者： J.N.Burkin M.d.lindsay S.A.Occhipinti E.-J.Holden Centre for Exploration Targeting School of Earth SciencesThe University of Western Australia

Prospectivity analyses are used to reduce the exploration search space for locating areas prospective for mineral *** scale of a study and the type of mineral system associated with the deposit control the evidence layers used as proxies that represent critical ore genesis *** particular,knowledge-driven approaches(fuzzy logic)use a conceptual mineral systems model from which data proxies represent the critical *** typically vary based on the scale of study and the type of mineral system being *** analyses utilising interpreted data to represent proxies for a mineral system model inherit the subjectivity of the interpretations and the uncertainties of the evidence layers used in the *** the case study presented,the prospectivity for remobilised nickel sulphide(NiS)in the west Kimberley,Western Australia,is assessed with two novel techniques that objectively grade interpretations and accommodate alternative mineralisation *** targets are then identified and supplied with a robustness assessment that reflects the variability of prospectivity value for each location when all models are *** first technique grades the strength of structural interpretations on an individual line-segment *** are obtained from an objective measure of feature evidence,which is the quantification of specific patterns in geophysical data that are considered to reveal underlying *** structures are weighted in the prospectivity model with grading values correlated to their feature *** technique allows interpreted features to contribute prospectivity proportional to their strength in feature evidence and indicates the level of associated stochastic *** second technique aims to embrace the systemic uncertainty of modelling complex mineral *** this approach,multiple prospectivity maps are each generated with different combinations of confidence values applied

关键词： Prospectivity Confidence Uncertainty Multiple models Mineral exploration Nickel

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Genomic insights into hybridization in a localized region of sympatry between pewee sister species(Contopus sordidulus × C. virens) and their chromosomal patterns of differentiation

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Chinese Birds 2016年第1期7卷 48-55页

作者： Joseph d.Manthey mark B.Robbins Biodiversity Institute University of Kansas department of Ecology and Evolutionary Biology University of Kansas

Background: The Great Plains of the United States includes a large number of hybrid and contact zones between bird species. The amount of gene flow between sister species in these zones ranges from very rare hybridization events to widespread and prevalent introgression. Some of these avian systems have been studied extensively, while others have been indeterminate of whether hybridization exists in areas of sympatry. Using genomic-level approaches allows investigation of genomic patterns of hybridization and gene flow between species—or lack ***: We investigated a narrow zone of sympatry in Nebraska, USA between pewee species(Contopus sordidulus and C. virens), for which no hybridization has been confirmed. We used thousands of single nucleotide polymorphisms to identify potential hybridization and investigate genomic patterns of differentiation between these two ***: We found evidence of multiple hybrid individuals in the contact zone. Little genomic variation was fixed between species, but a large proportion had differentiated allele frequencies between species. There was a positive relationship between genetic differentiation and chromosome ***: We provided the first conclusive evidence of hybridization between C. sordidulus and C. virens, in a region where secondary contact likely occurred due to human disturbance and habitat modification. The genomic patterns of differentiation affirm that these species split in the relatively recent past. Finally, the relationship of chromosome size and genetic differentiation may have resulted from differential rates of chromosomal recombination in songbirds and genetic differentiation between species largely due to genetic drift(possibly in concert with selection).

关键词： Contact zone Hybrid zone Hybridization Chromosomal patterns Next-generation sequencing Contopus North America

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Statistical variability and fragility assessment of ballistic perforation of steel plates for 7.62 mm AP ammunition

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defence Technology（防务技术） 2020年第3期16卷 503-513页

作者： mark G.Stewart Michael dNetherton Centre for Infrastructure Performance and Reliability The University of NewcastleNew South Wales2038Australia

The paper describes field test results of 7.62×51 mm M61 AP(armour piercing) ammunition fired into mild steel targets at an outdoor *** targets varied from 10 mm to 32 mm in *** tests recorded penetration depth,probability of perforation(i.e.,complete penetration),muzzle and impact velocities,bullet mass,and plate yield strength and *** measured penetration depth exhibited a variability of approximately±12%.The paper then compared ballistic test results with predictive models of steel penetration depth and thickness to prevent *** parameters were derived for muzzle and impact velocity,bullet mass,plate thickness,plate hardness,and model error.A Monte-Carlo probabilistic analysis was then developed to estimate the probability of plate perforation of 7.62 mm M61 AP ammunition for a range of impact velocities,and for mild steels,and High Hardness Armour(HHA) *** perforation fragility analysis considered the random variability of impact velocity,bullet mass,plate thickness,plate hardness,and model *** a probabilistic analysis allows for reliability-based design,where,for example,the plate thickness with 95% reliability(*** 1 in 20 shots will penetrate the wall) can be estimated knowing the probabilistic distribution of ***,it was found that the plate thickness to ensure a low 5% probability of perforation needs to be 11-15% thicker than required to have a 50/50 chance of perforation for mild steel *** would need to be 20-30% thicker if probability of perforation is reduced to zero.

关键词： Ballistics Probability Statistics Steel plates Armour steel Ammunition Experimental Perforation

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