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Time series analysis of mantle cycles Part Ⅰ:Periodicities and correlations among seven global isotopic databases

Geoscience Frontiers 2019年第4期10卷 1305-1326页

作者： stephen J. Puetz Kent c. condie Progressive Science Institute HonoluluHI96815USA New Mexico Institute of Mining and Technology SocorroNM87801USA

In this study,seven isotopic databases are presented and analyzed to identify mantle and crustal episodes on a global scale by focusing on periodicity ranging from 70 to 200 million years(Myr).The databases are the largest,or among the largest,compiled for each type of data-with an objective of finding some samples from every region of every continent,to make each database as global as conceivably *** databases contain zircon Lu/Hf isotopic data,whole-rock Sm/Nd isotopic data,U/Pb detrital zircon ages,U/Pb igneous zircon ages,U/Pb non-zircon ages,whole-rock Re/Os isotopic data,and large igneous province *** I of this study focuses on the periodicities of age histograms and geochemical averages developed from the seven databases,via spectral and cross-correlation *** physical cycles often propagate in exact integer multiples of a fundamental cycle,referred to as *** tests show that harmonic geological cycles of^93.5 and^187 Myr have persisted throughout terrestrial history,and the cyclicities are statistically significant for U/Pb igneous zircon ages,U/Pb detrital zircon ages,U/Pb zircon-rim ages,large igneous province ages,meanεHf(t)for all samples,meanεHf(t)values for igneous-only samples,and relative abundance of mafic *** important,cross-correlation analyses show these seven time-series are nearly synchronous(±7 Myr)with a model consisting of periodicities of 93.5 and 187 ***,the similarities between peaks in the 93.5 and 187 Myr mantle cycles and terminal ages of established and suspected superchrons provide a framework for predicting and testing superchron periodicity.

关键词： Zircon Database Isotope Statistical analysis Spectral analysis cross correlation

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Time series analysis of mantle cycles Part Ⅱ:The geologic record in zircons, large igneous provinces and mantle lithosphere

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Geoscience Frontiers 2019年第4期10卷 1327-1336页

作者： Kent c. condie stephen J. Puetz Department of Earth & Environmental Science New Mexico Institute of Mining and TechnologySocorroNM87801USA Progressive Science Institute HonoluluHI96815USA

Igneous and detrital zircons have six major U/Pb isotopic age peaks in common(2700 Ma,1875 Ma.1045 Ma,625 Ma,265 Ma and 90 Ma).For igneous rocks,each age peak is comprised of subpeaks with distinct geographic distributions and a subpeak age range per age peak≤100 *** are eight major LIP age peaks(found on≥10 crustal provinces)of which only four are in common to major detrital zircon age peaks(2715 Ma,1875 Ma,825 Ma,90 Ma).Of the whole-rock Re depletion ages,58%have correspo nding detrital zircon age peaks and 55%have corresponding LIP age *** age pea ks are fou nd in common to igneous zircon,detrital zircon,LIP,and Re depletion age time series(3225 Ma,2875 Ma,2145 Ma,2085 Ma,1985 Ma,1785 Ma,1455 Ma,1175 Ma,825 Ma,and 90 Ma).and these are very robust peaks on a global scale as recorded in both crustal and mantle *** 50%of the age peaks in each of these time series correspond to predicted peaks in a 94-Myr mantle cycle,including four of the ten peaks in common to all four time series(2875 Ma,1785 Ma,825 Ma and 90 Ma).Age peak widths and subpeak ranges per age peak suggest that mantle events responsible for age peaks arec distributions show three populations(≤1000 Ma,2500-1000 Ma,>2500 Ma),with the number of new provinces in which age peaks are represented decreasing with time within each *** breaks between the populations(at 2.5 Ga and 1 Ga)fall near the onsets of two transitions in Earth *** First Transition may represent a change from stagnant-lid tectonics into plate tectonics and the Second Transition,the onset of subduction of continental *** major factor controlling geographic distribution of age peaks is the changing locations of ***^2 Ga,age subpeaks and peaks are housed in orogens within or around the edges of crustal provinces,mostly in accretionary *** beginning at 1.9 Ga,collisional orogens become more *** coincidence in duration

关键词： Isotopic age peaks U/Pb zircon ages Re depletion ages Large igneous provinces Age peak correlation Mantle cycles

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When traditional ground support techniques aren’t enough–chemical injections can solve complex problems

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International Journal of Mining Science and Technology 2020年第1期30卷 119-122页

作者： cody Hildreth Frederick cybulski colton cook stephen c.Tadolini Minova Americas GeorgetownKY 40324USA Arch coal Inc.SharplesWV 25183USA

Broken and jointed ground is extremely hazardous and requires unique stabilization techniques to protect workers and critical *** techniques,even the most advanced pre-load to create roof compression,can leave large gaps of unconfined and separated *** roof can also be susceptible to water inflows which only exacerbate the support *** types of conditions existed on long-term development main entry accessing several future longwall *** geotechnical assessment identified well defined jointing systems that also permitted water to flow between the roof separations,which"lubricated"the roof material and minimized any frictional *** injections of polyurethane materials,Minova carbopur WS,was placed beyond the bolted horizon to move the water to the rib lines and reinforce the fractured and broken *** injection materials permitted the effective use of bolting patterns and helped ensure long-term stability of critical *** paper describes the evaluation techniques,design patterns,basis for chemical selection and application,and results and recommendations.

关键词： chemical injection Polyurethane Water stoppage

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Laboratory and field testing of bolting systems subjected to highly corrosive environments

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International Journal of Mining Science and Technology 2017年第1期27卷 101-106页

作者： Meikle Tom Tadolini stephen c. Sainsbury Bre-Anne Bolton John Minova Richmond Vale NSW 2327Australia Minova Georgetown KY 43204USA Mining and Resource Engineering Monash University VIC 3800 CaulfieldAustralia

The capacity of ground support components which have been affected by corrosion is reduced and may ultimately lead to dynamic failure of the component and the strata. In order to maintain an effective,long-term ground support system, significant campaigns of rehabilitation are often required in corrosion affected areas which also expose the workers to hazardous conditions. The most common corrosion protection for steel ground support utilises sacrificial systems such as galvanising. Galvanising has previously been proven to be susceptible to some corrosion processes. Stainless steel is the most effective in resistance to corrosion, but can be cost prohibitive, and its mechanical properties often make it unsuited to use in ground support components. Providing an outer protective plastic coating to bolts has proven to be an effective means of protecting the inner steel bar from corrosion. However, these support systems tend to be susceptible to coating damage, and require post cement grouting to provide full encapsulation. In comparison to a standard bolt/resin system, they can be slow to install and *** systems have also been shown to reduce overall load transfer performance of the bolting system. In order to provide a higher level of corrosion protection whilst maintaining current installation practices and bolting cycle times, Minova has developed the Enduro^(TM)steel ground support range. The Enduro^(TM) range consists of standard Minova steel ground support components which have been treated with a unique coating process. The Enduro^(TM)coating has been tested in the harshest of conditions, in laboratory controlled conditions and in underground trials. It has been proven to effectively resist or completely eliminate the formation of corrosion, even in the most aggressive environments. This paper explains the process and provides the details of the laboratory and underground corrosion performance testing carried out on Enduro^(TM)ground support product

关键词： corrosion coatings Galvanised Salt spray Accelerated corrosion testing

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Tekcrete Fast~: Fiber-reinforced, rapid-setting sprayed concrete for rib and surface control

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International Journal of Mining Science and Technology 2018年第1期28卷 29-34页

作者： stephen c.Tadolini Peter S.Mills David R.Burkhard Minova USA IncGeorgetownKYUSA San Juan coal company WaterflowNMUSA

Fiber-reinforced spayed concrete has been used for several years in civil and tunneling *** conducted to reduce cure times and increase compressive and flexural strengths resulted in the development of Tekcrete Fast~, a cementitious product capable of obtaining 41 MPa compressive strength and 8 MPa flexural strength in only 3 h and reaching 7 d strengths of 62 and 11.7 MPa, respectively.A single bag product that uses conventional shotcrete and gunite application systems makes it a natural crossover product for mining *** discovery of incredible adhesion properties and high resistance to chloride permeability helps ensure long-term stability and increases the ease of *** results from Disaster city~ in Texas and the application for rehabilitating a coal mine belt entry are *** case study illustrates the effectiveness of the product in stabilizing a coal mine beltway and adjacent cross-cuts that were subjected to progressive sloughage due to humidity and cyclical loading.

关键词： Sprayed concrete coal mine High strength concrete Polypropylene fiber

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Monitoring the built-up environment of Shanghai on the street-block level using SAR and volunteered geographic information

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International Journal of Digital Earth 2017年第7期10卷 675-686页

作者： Michael Jendryke stephen c.Mcclure Timo Balz Mingsheng Liao State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanPeople’s Republic of China collaborative Innovation center for Geospatial Technology Wuhan UniversityWuhanPeople’s Republic of China

In this geo-statistical analysis of change detection,we illustrate the evolution of the built-up environment in Shanghai at the street-block *** on two TerraSAR-X image stacks with 36 and 15 images,covering the city centre of Shanghai for the time period from 2008 to 2015,a set of coherence images was created using a small baseline *** road network from Open Street Map,a volunteered geographic information product,serves as the input dataset to create street-blocks.A street-block is surrounded by roads and resembles a ground parcel,a real estate property–a cadastral *** coherence information is aggregated to these street-blocks for each observation and the variation is analysed over *** analysis of spatial autocorrelation reveals clusters of similar *** result is a detailed map of Shanghai highlighting areas of *** argue that the aggregation and grouping of synthetic aperture radar coherence image information to real-world entities(street-blocks)is comprehensible and relevant to the urban planning ***,this research is a contribution to the community of urban planners,designers,and government agencies who want to monitor the development of the urban landscape.

关键词： SAR change detection urban area volunteered geographic information

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Parameters selection in gene selection using Gaussian kernel support vector machines by genetic algorithm

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第10期6卷 961-973页

作者：毛勇周晓波皮道映孙优贤 WONG stephen T.c. National Laboratory of Industrial control Technology Institute of Modern Control Engineering Zhejiang University Hangzhou 310027 China Harvard center for Neurodegeneration and Repair Harvard Medical School and Brigham and Women’s Hospital Harvard Medical School Harvard University Boston MA 02115 USA

In microarray-based cancer classification, gene selection is an important issue owing to the large number of variables and small number of samples as well as its non-linearity. It is difficult to get satisfying results by using conventional linear sta- tistical methods. Recursive feature elimination based on support vector machine (SVM RFE) is an effective algorithm for gene selection and cancer classification, which are integrated into a consistent framework. In this paper, we propose a new method to select parameters of the aforementioned algorithm implemented with Gaussian kernel SVMs as better alternatives to the common practice of selecting the apparently best parameters by using a genetic algorithm to search for a couple of optimal parameter. Fast implementation issues for this method are also discussed for pragmatic reasons. The proposed method was tested on two repre- sentative hereditary breast cancer and acute leukaemia datasets. The experimental results indicate that the proposed method per- forms well in selecting genes and achieves high classification accuracies with these genes.

关键词： Gene selection, Support vector machine (SVM), Recursive feature elimination (RFE), Genetic algorithm (GA),Parameter selection

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Predisposing factors’effects on mortality of oak (Quercus) and hickory (carya) species in mature forests undergoing mesophication in Appalachian Ohio

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Forest Ecosystems 2021年第1期8卷 81-94页

作者： Don c.Radcliffe David M.Hix stephen N.Matthews School of Environment and Natural Resources The Ohio State University2021 Coffey RoadColumbus OH 43210USA School of Environmental and Forest Sciences University of WashingtonBox 352100Seattle WA 98195-2100USA

Background:Mature oak(Quercus spp.)and hickory(carya spp.)trees are gradually being replaced by more shadetolerant tree species across the eastern U.S.,likely due to fire suppression and increased *** and hickories are highly valuable to wildlife;therefore,studying their mortality patterns can provide information on the longevity of habitat quality for many animal *** mortality has most often been studied following large oak decline events,but background mortality rates in forests with aging oak and hickory canopies warrant equal attention,especially in the context of widespread oak and hickory regeneration ***:We studied background mortality rates of five oak and one hickory species over a 23–25 year time period(1993–1995 to 2018),using 821/20th hectare permanent plots on the Marietta Unit of the Wayne National Forest in southeastern *** calculated mortality rates based on remeasurement of individual trees for white oak(Quercus alba),chestnut oak(Quercus montana),northern red oak(Quercus rubra),black oak(Quercus velutina),scarlet oak(Quercus coccinea),and pignut hickory(carya glabra).For each of these species other than scarlet oak,we also modeled the relationships of mortality probability with a priori topographic,soil,stand structural,and individual tree covariates,using a mixed-effects logistic regression ***:The species with the highest mortality rate was scarlet oak(61.3%),followed by northern red oak(41.4%),black oak(26.7%),pignut hickory(23.9%),white oak(23.4%),and chestnut oak(19.1%).In our models,northern red oak mortality was associated with more mesic slope positions,shallower solums,more acidic soils,and older stand *** hickory and chestnut oak mortality rates were associated with higher basal areas on the plot,while white oak mortality showed the opposite ***:Our data suggest that red oak subgenus trees in mature forests of our area will become increasingly uncommon relative t

关键词： Mortality Quercus carya Mesophication Wildlife habitat

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cell membrane coating for reducing nanoparticle-induced inflammatory responses to scaffold constructs

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Nano Research 2018年第10期11卷 5573-5583页

作者： Zhiyuan Fan Peter Y. Li Junjie Deng stephen c. Bady Hao cheng Department of Materials Science and Engineering Drexel University Philadelphia Pennsylvania 19104 USA Engineering Research center of clinical Functional Materials and Diagnosis & Treatment Devices of Zhejiang Province Wenzhou Institute of Biomaterials and Engineering Chinese Academy of Sciences Wenzhou 325011 China

The controlled release of therapeutics from microparticles or nanoparticles （NPs） has been well-studied. Incorporation of these particles inside biomaterial scaffolds is promising for tissue regeneration and immune modulation. However, these particles may induce inflammatory and foreign body responses to scaffold constructs, limiting their applications. Here we show that widely used poly（lactic-co-glycolic acid） nanoparticles （PLGA NPs） formed by double emulsion dramatically increased neutrophil infiltration and pro-inflammatory cytokines in alginate scaffolds 1 day after the subcutaneous injection of the scaffolds into mice. The coating of red blood cell （RBc） membranes on PLGA NPs completely eliminated these short-term inflammatory responses. For a longer term of 10 days, neither PLGA NPs nor RBc membrane-coated NPs exerted a significant effect on the infiltration of neutrophils or macrophages in alginate scaffolds, possibly due to the degradation and/or clearance of NPs by infiltrating cells. Despite the extensive exploration of cell membrane-coated NPs, our study is the first to investigate the effects of cell membrane coating on foreign body reaction to NPs. By harnessing the natural biocompatibility of cell membranes, our strategy of anti-inflammatory protection for scaffolds may be pivotal for many applications such as those relying on the recruitment of stem cells and/or progenitor ceils to scaffolds.

关键词： regenerative medicine wound healing drug delivery endothelial cell immune tolerance

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Oxygen Radical Generation as an Index of Neurotoxic Damage

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Biomedical and Environmental Sciences 1991年第1期4卷 217-223页

作者： stephen c.BONDY cARL P.LEBEL Department of community and Environmental Medicine University of california Irvine CA Arthur D. Little Inc. Chemical and Life Sciences Acorn Park Cambridge 92717 Massachusetts 02140

Biochemical, anatomical, and physiological characteristics of the brain make it especially vulnerable to insult. Specifically, some of these characteristics such as myelin and a high energy requirement provide for the introduction of free radical-induced insult. Recently, the biochemistry of free radicals has received considerable attention. It also has become increasingly suggestive that many drug and chemical-induced toxicities may be evoked via free radicals and oxidative stress. Major points addressed in this work are the regulation of neural-free radical generation by antioxidants and protective enzymes, xenobiotic-induced disruption of cerebral redox status, and specific examples of neurotoxic agent-induced alterations in free radicals as measured by the fluorescent probe dichlorofluorescein. This article considers that free radical mechanisms may contribute significantly to the properties of several diverse neurotoxic agents and proposes that free radicals may be common phenomena of neurotoxicity.

关键词： Oxygen Radical Generation as an Index of Neurotoxic Damage

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