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Targeted principle component analysis:A new motion artifact correction approach for near-infrared spectroscopy

journal of Innovative Optical Health Sciences 2014年第2期7卷 98-105页

作者： Meryen A.Yücel julitte Selb robert j.c.ooper David A.Boas Athinoula A.Martinos center for Biomedical Imaging Department of Radiology Massachusetts General Hospital Haruard Medical SchoolCharlestownMAUSA Department of Medical Physics and Bioengineering University college London LondonUK

As near-infrared spectroscopy(NIRS)broadens its application area to diferent age and diseasegroups,motion artifacts in the NIRS signal due to subject movement is becoming an *** artifacts generally produce signal fiuctuations that are larger than physio-logical NIRS signals,thus it is cruciai to corect for them before obtaining an cstimate ofstimulusevoked hemodynamic responses.,There are various methods for correction such as principlecomponent analy sis(P cA),wavelet-based filt ering and spline int ***,we introduce anew approach to motion artifact correction,targeted principle component analysis(PcA),which incorporates a PcA filter only on the segments of data identified as motion *** expected that this will overcome the issues of filtering desired signals that plagues standardPcA fitering of entire data *** compared the new approach with the most efiective motionartifact correction algorithms on a set of data acquired simultaneously with a collodion-fixedprobe(low motion artifact content)and a standard Velcro probe(high motion artifact content).Our results show that tPcA gives statistically better results in recovering hemodynamic responsefunction(HRF)as compared to wavelet-based fltering and spline interpolation for the *** resulis in a significant reduction in mean-squauared'error(MSE)and significant en-hancement in Pearson's correlation coeficient to the true HRF,The collodion-fixed fiber probewith no motion correction performed better than the Velcro probe corrected for motion artifactsin terms of MSE and Pearson's correlation ***,if the experimental study permits,the use of a collodion-fixed fiber probe may be desirable.I the use of a collodion-fixed probe is notfeasible,then we suggest the use of tP cA in the processing of motion artifact contaminated data.

关键词： Wavelet spline collodion-fixed fiber.

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Ophiolites:Identification and tectonic significance in space and time

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Geoscience Frontiers 2023年第6期14卷 380-385页

作者： Kent c.condie robert j.Stern Department of Earth&Environmental Science New Mexico Institute of Mining and TechnologySocorroNM 87801USA Geosciences Department University of Texas at DallasRichardsonTX 75080USA

Ophiolites are fragments of oceanic lithosphere that are produced at spreading centers at ocean ridges,back arc basins,or forearcs during subduction initiation,and are key indicators of plate *** it is widely agreed that ophiolites are remnants of oceanic crust and associated depleted mantle preserved in orogens,the recognition of ophiolites and their tectonic significance is still a topic of discussion and *** propose that ophiolites can be recognized in the geologic record by some combination of genetically related pillow basalt,layered gabbro,sheeted dykes,podiform chromite,harzburgite or/and *** igneous rocks have either ocean-ridge basalt or immature oceanic arc basalt chemical *** a scoring system of 1–11 for ophiolite confidence level,scores of8 are considered confident,6–8 probable,andcores6 areconfident ophiolite(score of 8)is the Zunhua ophiolite in eastern china at 2550 Ma,and the oldest well documented sheeted dykes occur in the jormua and Purtuniq ophiolites at 2000–1950 *** do not become geographically widespread until after 900 Ma,and most ophiolites of all ages formed in a forearc(subduction initiation)tectonic *** ophiolite production requires plate tectonics,subduction must have begun at least locally by 2700 Ma but did not become widespread until after 2000 *** abundance of ophiolites after 900 Ma may reflect better preservation of subduction-related ophiolites,or to an increasing global network of interconnected *** frequency peaks in the geologic record partially reflect geographic regions where ophiolites have been extensively studied rather than monitoring the production rate of ophiolites,but the scarcity of>900 Ma ophiolites is probably real.

关键词： Ophiolite Plate tectonics Subduction initiation Forearc Ocean ridge Tectonic setting Supercontinent

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X-ray Multiple Diffraction Topographic Imaging Technique For Growth History Study of Habit Modifying Impurity Doped crystals

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chemical Research in chinese Universities 2004年第4期20卷 411-416页

作者： LAI X. MA c. K. j. robert M. c. Miller Institute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsCCLRC Daresbury Laboratory Daresbury Leeds LS2 9JT UKLeeds LS2 9JT UKLeeds LS2 9JT UKWarrington Cheshire WA4 4AD UK

A novel crystal characterization instrument has been built up in which a combination of X-ray multiple diffraction and X-ray topography is applied to enabling the cross-correlation between micro-crystallographic symmetry and its spatial dependence in relation to lattice defects. This facility is used to examine, in a self-consistent manner, growth sector-dependant changes to both the crystallographic structure and the lattice defects associated with the action of habit-modifying additives in a number of representative crystal growth systems. In addition, the new instrument can be used to probe micro-crystallographic aspects(such as distortion to crystal symmetry) and relate these in a spatially resolved manner to the crystal defect structure in crystals doped with known habit modifiers.

关键词： X-ray diffraction X-ray multiple diffraction X-ray topography Habit modification crystal growth Growth defects

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conditional coherent risk measures and regime-switching conic pricing

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Probability, Uncertainty and Quantitative Risk 2021年第4期6卷 267-300页

作者： Engel john c Dela Vega robert j Elliott UniSA Business University of South AustraliaSA 5000 AdelaideAustralia Haskayne School of Business University of CalgaryCalgaryAlbertaT2N 1N4Canada

This paper introduces and represents conditional coherent risk measures as essential suprema of conditional expectations over a convex set of probability measures and as distorted expectations given a concave distortion function.A model is then developed for the bid and ask prices of a European-type asset by a conic *** price process is governed by a modified geometric Brownian motion whose drift and diffusion coefficients depend on a Markov *** bid and ask prices of a European-type asset are then characterized using conic quantization.

关键词： conditional coherent risk measures Markov chains Regime-switching conic finance European options Distortion functions conic quantization

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Endangered species and nature conservation: science issues and challenges

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Integrative Zoology 2008年第2期3卷 75-82页

作者： robert c.SZARO US Geological Survey Biological Resources DisciplineRestonVirginiaUSA

The issues and challenges facing us in ensuring the survival of as many species and ecosystems as possible call fora renewed research focus to address how to improve management strategies and policy making now and into thefuture. The key issues to be addressed by activities of the International Union of Forest Research Organization’s(IUFRO) Task Force on Endangered Species and Nature conservation include such issues as: (i) preventing speciesfrom being listed by maintaining species populations at sufficient levels that they do not require listing;(ii) recoveringthreatened and endangered species;(iii) developing management practices and strategies;(iv) balancingactions affecting suites of threatened or endangered species;(v) developing conservation strategies for specieswithout definitive taxonomic treatments;(vi) dealing with global change;(vii) dealing with invasive species;and(viii) restoring critical habitats.

关键词： endangered species management practices nature conservation restoration science issues

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Effective teaching of endoscopy:a qualitative study of the perceptions of gastroenterology fellows and attending gastroenterologists

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Gastroenterology Report 2016年第2期4卷 125-130,I0002页

作者： Daniel j.Zanchetti Samuel A.Schueler Brian c.jacobson robert c.Lowe Boston University Medical center BostonMAUSA

Background:There is little information describing the perceptions of gastroenterology fellows and attending gastroenterologists of what constitutes effective teaching of *** sought to identify common themes regarding endoscopy training methods and their impact among fellows and ***:Focus group exercises and surveys were conducted among fellows,about educational resources,teaching techniques and ways of improving the teaching of *** fellows identified the‘best’teachers of endoscopy,who were interviewed regarding their training in endoscopy,their teaching methods,key points of information,and opinions on endoscopy ***:Nineteen fellows(68%)had attended the American Society for Gastrointestinal Endoscopy First Year Fellows’Endoscopy course and found it very *** fellows(46%)had exposure to an endoscopy simulator,but their median duration of use was only 1 *** two out of five fellowship programs used a formal endoscopic skill assessment tool and none of the programs had an endoscopy curriculum of which the fellows were *** reported that they learned endoscopy best by performing *** also volunteered that attending gastroenterologists used variable teaching methods,and might benefit from instruction on how to teach *** attending gastroenterologists(77%)had received training in advanced procedures;none received formal training on teaching endoscopy:they all felt that such training would be ***:A standardized endoscopy curriculum may be beneficial to fellows,who prefer to learn endoscopy by performing procedures—but they want explicit and specific *** those attending and the fellows thought that formal instruction for attending gastroenterologists on how to teach endoscopy would be beneficial,indicating a role for a‘teachthe-teacher’curriculum.

关键词： endoscopy curriculum teaching endoscopy gastroenterology fellowship training

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A critical Review of the Evidence for M32 being a compact Dwarf Satellite of M31 rather than a More Distant Normal Galaxy

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chinese journal of Astronomy and Astrophysics 2008年第4期8卷 369-384页

作者： c. Ke-shih Young Malcolm j. currie robert j. Dickens A-Li Luo Tong-jie Zhang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Department of Physics University of Hong Kong Hong Kong China School of Physics University of New South Wales Sydney 2052 Australia Rutherford Appleton Laboratory Chilton Didcot Oxfordshire OX 11 0QX Great Britain Department of Astronomy Beijing Normal University Beijing 100875 China

Since Baade＇s photographic study of M32 in the mid 1940s, it has been accepted as an established fact that M32 is a compact dwarf satellite of M31. The purpose of this paper is to report on the findings of our investigation into the nature of the existing evidence. We find that the case for M32 being a satellite of M31 rests upon Hubble Space Telescope （HST） based stellar population studies which have resolved red-giant branch （RGB） and red clump stars in M32 as well as other nearby galaxies. Taken in isolation, this recent evidence could be considered to be conclusive in favour of the existing view. However, the conventional scenario does not explain M32＇s anomalously high central velocity dispersion for a dwarf galaxy （several times that of either NGc 147, NGc 185 or NGc 205） or existing planetary nebula observations （which suggest that M32 is more than twice as distant as M31） and also requires an elaborate physical explanation for M32＇s inferred compactness. conversely, we find that the case for M32 being a normal galaxy, of the order of three times as distant as M31, is supported by：（1） a central velocity dispersion typical of intermediate galaxies, （2） the published planetary nebula observations, and （3） known scaling relationships for normal early-type galaxies. However, this novel scenario cannot account for the high apparent luminosities of the RGB stars resolved in the M32 direction by HST observations. We are therefore left with two apparently irreconcilable scenarios, only one of which can be correct, but both of which suffer from potentially fatal evidence to the *** suggests that current understanding of some relevant fields is still very far from adequate.

关键词： galaxies:individual M32 - galaxies distances and redshifts - galaxies dwarf- galaxies elliptical and lenticular, cD - galaxies fundamental parameters

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Eastern Dharwar craton,India:continental lithosphere growth by accretion of diverse plume and arc terranes

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Geoscience Frontiers 2012年第3期3卷 225-240页

作者： c.Manikyamba robert Kerrich National Geophysical Research Institute Council of Scientific and Industrial ResearchHyderabad 500 007India Department of Geological Sciences University of SaskatchewanSaskatoonSaskatchewan S7N 5E2Canada

Abstract Greenstone belts of the eastern Dharwar craton, India are reinterpreted as composite tecto- nostratigraphic terranes of accreted plume-derived and convergent margin-derived magmatic sequences based on new high-precision elemental data. The former are dominated by a komatiite plus Mg-tholeiitic basalt volcanic association, with deep water siliciclastic and banded iron formation （BIF） sedimentary rocks. Plumes melted at 〈90 km under thin rifted continental lithosphere to preserve intrao- ceanic and continental margin aspects. Associated alkaline basalts record subduction-recycling of Me- soarchean oceanic crust, incubated in the asthenosphere, and erupted coevally with Mg basalts from a heterogeneous mantle plume. Together, komatiites-Mg basalts-alkaline basalts plot along the Phanero- zoic mantle array in Th/Yb versus Nb/Yb coordinate space, representing zoned plumes, establishing that these reservoirs were present in the Neoarchean mantle. convergent margin magmatic associations are dominated by tholeiitic to calc-alkaline basalts compo- sitionally similar to recent intraoceanic arcs. As well, boninitic flows sourced in extremely depleted mantle are present, and the association of arc basalts with Mg-andesites-Nb enriched basalts-adakites documented from cenozoic arcs characterized by subduction of young （〈20 Ma）, hot, oceanic litho- sphere. consequently, cenozoic style ＂hot＂ subduction was operating in the Neoarchean. These diverse volcanic associations were assembled to give composite terranes in a subduction-accretion orogen at -2.7 Ga, coevally with a global accretionary orogen at -2.7 Ga, and associated orogenic gold mineralization.

关键词： continental lithospheregrowth Zoned plume Subduction-accretion Neoarchean mantle Geodynamics Eastern Dharwar craton

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Growth factor delivery using extracellular matrix-mimicking substrates for musculoskeletal tissue engineering and repair

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Bioactive Materials 2021年第7期6卷 1945-1956页

作者： robert c.H.Gresham chelsea S.Bahney j.Kent Leach Uc Davis Department of Biomedical EngineeringDavisCAUSA Steadman Phillippon Research Institute VailCOUSA UcSF Orthopaedic Trauma Institute San FranciscoCAUSA Uc Davis Health Department of Orthopaedic SurgeryDavisCAUSA

Therapeutic approaches for musculoskeletal tissue regeneration commonly employ growth factors(GFs)to influence neighboring cells and promote migration,proliferation,or *** promising results in preclinical models,the use of inductive biomacromolecules has achieved limited success in translation to the *** field has yet to sufficiently overcome substantial hurdles such as poor spatiotemporal control and supraphysiological dosages,which commonly result in detrimental side *** presentation and retention of biomacromolecules is regulated by the extracellular matrix(EcM),which acts as a reservoir for GFs via electrostatic *** in the manipulation of extracellular proteins,decellularized tissues,and synthetic EcM-mimetic applications across a range of biomaterials have increased the ability to direct the presentation of *** application of biomaterial technologies utilizing EcM mimetics increases tissue regeneration without the reliance on supraphysiological doses of inductive *** review describes recent strategies to manage GF presentation using EcM-mimetic substrates for the regeneration of bone,cartilage,and muscle.

关键词： Growth factor Extracellular matrix Spatiotemporal control Tissue engineering Affinity

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Impact of carbon-based nutrient enhancement on biofiltration performance for drinking water treatment

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journal of Environmental Sciences 2019年第8期31卷 124-131页

作者： Yu Zhao Liz Taylor-Edmonds robert c.Andrews Department of civil and Mineral Engineering University of Toronto

Incorporation of a carbon-based nutrient enhancementstrategy for drinking water biofiltration is an attractive option, especially for source waters which contain recalcitrant organics. This study compared biofilters that were operated in parallel and individually enhanced with amino acids(including alanine, phenylalanine, and tryptophan), inulin, and sucrose to increase biomass concentration and promote biodegradation of dissolved organic carbon(DOc) in the source water, including disinfection by-product(DBP) precursors. Biomass activity was characterized by measuring adenosine tri-phosphate(ATP), dissolved oxygen(DO) consumption, and through the use of laccase and esterase enzyme assays. Performance was evaluated in terms of headloss,turbidity, p H, DOc, UV254, and DBP formation potential(DBP FP). The introduction of carbonbased nutrients significantly increased biomass activity, where ATP values peaked at 976 ng/g of filter media, 853 ng/g, and 513 ng/g for amino acids, inulin, and sucrose-spiked biofilters,respectively, while a non-spiked control only reached 104 ng/g. DO utilization by the enhanced biofilters was significantly higher than the control, with a strong correlation between ATP and DO uptake observed for all filters(R^2> 0.74). Laccase and esterase enzyme activities of enhanced biofilters were also elevated(p > 0.05), suggesting greater biodegradation potential. Operational parameters such as headloss development and turbidity control were not impaired by carbon supplementation strategies or an increase in biomass concentration and activity. However, the enhancement strategy did not provide improvement in terms of source water carbon removal(DOc and UV254) or DBP FP when treated filters were compared to a control.

关键词： Biological filtration carbon enhancement Biomass Disinfection by-products Dissolved organic carbon

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