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Frontiers of mathematics in China 2013年第1期8卷 85-105页

作者： Kelly J. pearson Tan ZHANG Department of mathematics and Statistics Murray State University Murray KY 42071-0009USA

Based on the generalized characteristic polynomial introduced by J. Canny in Generalized characteristic polynomials [J. Symbolic Comput., 1990, 9（3）： 241-250], it is immediate that for any m-order n-dimensional real tensor, the number of distinct H-eigenvalues is less than or equal to n（m-1）n-1. However, there is no known bounds on the maximal number of distinct H- eigenvectors in general. We prove that for any m ~〉 2, an m-order 2-dimensional tensor sd exists such that d has 2（m - 1） distinct H-eigenpairs. We give examples of 4-order 2-dimensional tensors with six distinct H-eigenvalues as well as six distinct H-eigenvectors. We demonstrate the structure of eigenpairs for a higher order tensor is far more complicated than that of a matrix. Further- more, we introduce a new class of weakly symmetric tensors, called p-symmetric tensors, and show under certain conditions, p-symmetry will effectively reduce the maximal number of distinct H-eigenveetors for a given two-dimensional tensor. Lastly, we provide a complete classification of the H-eigenvectors of a given 4-order 2-dimensional nonnegative p-symmetric tensor. Additionally, we give sufficient conditions which prevent a given 4-order 2-dimensional nonnegative irreducible weakly symmetric tensor from possessing six pairwise distinct H-eigenveetors.

关键词： Symmetric tensor H-eigenpairs

Experimental quantum simulation of Avian Compass in a nuclear magnetic resonance system

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Science China(Physics,mechanics & Astronomy) 2016年第12期59卷 22-26页

作者： Jason pearson Guanru Feng Chao Zheng GuiLu Long The Innovative Center of Quantum matter State Key Laboratory of Low-dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Department of Physics North China University of TechologyBeijing 100144China Tsinghua National Laboratory of Information Science and Technology Beijing 100084China

Avian magnetoreception is the capacity for avians to sense the direction of the Earth's magnetic field. Discovered more than forty years ago, it has attracted intensive studies over the years. One promising model for describing this capacity in avians is the widely used reference-and-probe model where radical pairs within the eyes of bird combines to form singlet and triplet quantum *** yield depends on the angle between the Earth's magnetic field and the molecules' axis, hence the relative value of yield of the singlet state or triplet state enables avians to sense the direction. Here we report the experimental demonstration of avian magnetoreception in a nuclear magnetic resonance quantum information processor. It is shown clearly from the experiment that the yield of the singlet state attains maximum when it is normal to the Earth's magnetic field, and the experimental results agree with theory very well.

关键词： Nmr quantum information processing quantum simulation avian magnetoreception quantum biology

Agrobacterium tumefaciens: A Bacterium Primed for Synthetic Biology

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BioDesign research 2020年第1期2020卷 91-106页

作者： mitchell G.Thompson William m.moore Niklas F.C.Hummel Allison N.pearson Collin r.Barnum Henrik V.Scheller Patrick m.Shih Joint BioEnergy Institute EmeryvilleCAUSA Environmental Genomics and Systems Biology Division Lawrence Berkeley National LaboratoryBerkeleyCAUSA Department of Plant Biology University of California-DavisDavisCAUSA Department of Plant and microbial Biology University of California-BerkeleyBerkeleyCAUSA Genome Center University of California-DavisDavisCAUSA

Agrobacterium tumefaciens is an important tool in plant biotechnology due to its natural ability to transfer DNA into the genomes of host *** manipulations of *** have yielded considerable advances in increasing transformational efficiency in a number of plant species and ***,there is overwhelming evidence that modulating the expression of various mediators of *** virulence can lead to more successful plant transformation;thus,the application of synthetic biology to enable targeted engineering of the bacterium may enable new opportunities for advancing plant *** this review,we highlight engineering targets in both *** and plant hosts that could be exploited more effectively through precision genetic control to generate high-quality transformation events in a wider range of host *** then further discuss the current state of *** and plant engineering with regard to plant transformation and describe how future work may incorporate a rigorous synthetic biology approach to tailor strains of *** used in plant transformation.

关键词： transformation enable rigorous

Exploring emerald global geochemical provenance through fingerprinting and machine learning methods

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Artificial Intelligence in Geosciences 2024年第1期5卷 202-219页

作者： raquel Alonso-Perez James m.D.Day D.Graham pearson Yan Luo manuel A.Palacios raju Sudhakar Aaron Palke Earth and Planetary Science Department Harvard UniversityCambridgeMA02138USA Scripps Institution of Oceanography University of California San DiegoLa JollaCA92037USA University of Alberta EdmontonABT6G 2R3Canada Eigenvector research Inc.manson WA98831USA rockhurst University Kansas CityMO64110USA Gemological Institute of America CarlsbadCA92008USA

Emeralds-the green colored variety of beryl-occur as gem-quality specimens in over fifty deposits *** digital traceability methods for emerald have limitations,sample-based approaches offer robust alterna-tives,particularly for determining the geographic origin of *** factors make emerald suitable for provenance studies and hence for developing models for origin ***,the diverse elemental chemistry of emerald at minor(race levels(mw)exhibits unique inter-element fractionations between global ***,minimally destructive techniques,including laser ablation inductively coupled plasma mass spectrometry(LA-ICP-mS),enable measurement of these diagnostic elemental ***,when applied to extensive datasets,machine learning(mL)techniques enable the creation of predictive models and statistical discrimination with adequate characterization of the *** study em-ploys a carefully selected dataset comprising more than 1000 LA-ICP-mS analyses of gem-quality emeralds,enriched with new *** dataset represents the largest available for global emerald *** con-ducted unsupervised exploratory analysis using Principal Component Analysis(PCA).For machine learning-based classification,we employed Support Vector machine Classification(SVm-C),achieving an initial accu-racy rate of 79%.This was enhanced to 96.8%through the use of hierarchical SVm-C with PCA filters as our modeling *** mL models were trained using the concentrations of eight statistically significant ele-ments(Li,V,Cr,Fe,Sc,Ga,rb,Cs).By leveraging high-quality LA-ICP-mS data and mL techniques,accurate identification of the geographical origin of emerald becomes *** models are important for accurate provenance of emerald,and from a geochemical perspective,for understanding the formation environments of beryl-bearing pegmatites and shales.

关键词： Beryl Provenance LA-ICP-mS machine learning multivariate analysis Trace elements

Zircon within chromitite requires revision of the tectonic history of the Eoarchean Itsaq Gneiss complex,Greenland

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Geoscience Frontiers 2023年第6期14卷 273-285页

作者： Hikaru Sawada Tomoaki morishita Adrien Vezinet richard Stern Kenichiro Tani Ikuya Nishio Kanta Takahashi D.Graham pearson Kristoffer Szilas Department of Earth System Science University of ToyamaToyamaJapan X-Star Japan Agency for Marine-Earth Science and Technology(JAMSTEC)KanagawaJapan Faculty of Geosciences and Civil Engineering Kanazawa UniversityKanazawaJapan Lamont-Doherty Earth Observatory Columbia UniversityPalisadesUSA Volcanoes and Earth’s Interior research Center JAMSTECKanagawaJapan Department of Earth and Atmospheric Sciences University of AlbertaEdmontonCanada Canadian Centre for Isotopic microanalysis University of AlbertaEdmontonCanada National museum of Nature and Science TsukubaJapan Department of Geosciences and Natural resource management University of CopenhagenCopenhagenDenmark

The Ujaragssuit Nunat layered(UNL)unit in the Itsaq Gneiss Complex,west Greenland,has been consid-ered to contain one of the oldest chromitites on Earth based on~ca.4.1 Ga Hadean whole rock Pt-Os model ages and ca.3.81 Ga zircon U-Pb age of the surrounding *** study obtained zircon from the chromitite within this unit as well as granitoid sheets that intruded into the UNL ***-situ U-Pb-Hf-O isotope measurements were made on the *** from both the chromitite and the intrusive granitoids show concordant U-Pb ages of ca.2.97-2.95 *** contrast,Hf and 0 isotopic anal-yses indicate that zircons in the chromitites have a different origin from those in the intrusive *** from granitoids yielded Th/U ratios higher than 0.2,initial Hf isotope ratios of 0.2805-0.2807(i.e,initial:Hf value of-11 to-5),andδ^(18)O values of mostly 6.0‰-7.0‰,which are typical for felsic igneous rocks in Archean continental *** least altered zircons from a chromitite exhibited initial Hf isotope ratios of 0.28078-0.28084(i.e.,initial:Hf value of-1.1 to-0.4),close the chondritic value at ca.3.0 Ga and the depleted mantle at ca.3.2 *** zircons also haveδ^(18)O values of 4.2‰6.1‰which correspond to typical mantle *** other chromitite zircons yielded Th/U ratios lower than 0.1,and Hf and 0 isotopic compositions ranging between the least altered zircons and the intrusive granitoid *** results indicate that the zircons in the chromitites crystallized before or during the 2.97-2.95 Ga granitoid intrusion and most of the zircons were altered by subsequent ***,the present results suggest that zircons in the chromitites originally had depleted Hf iso-topic compositions at ca.3.2-3.0 *** can be explained by two different models of the evolution of the UNL *** is that if the UNL unit was formed at>3.81 Ga as previously thought,with the zircons in the chromitites subsequently being precipitated by ca.3.2-2.95 G

关键词： Archean Itsaq gneiss complex Ultramafic rock metasomatism

Transition-Zone mineral Assemblages in Peridotite massifs, Tibet: Implications for Collision-zone Dynamics and Orogenic Peridotites

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Acta Geologica Sinica(English Edition) 2015年第A02期89卷 90-91页

作者： W. L. GrIFFIN N.m. mCGOWAN J. m. GONZALEZ-JImENEZ E. A. BELOUSOVA D. HOWELL J. C. AFONSO YANG J.S SHI r Suzanne Y. O'rEILLY N. J. pearson CCFS/GEmOC Earth and Planetary Sciences Macquarie University NSW 2109 Australia State Key Laboratory for Continental Tectonics and Dynamics CAGS Beijing 100037 China Institute for Tibetan Plateau research CAS Beijing 100085 China

Diamonds have been reported from Tibetan ＂ophiolites＂ for 〉30 years, but have been widely dismissed as contaminants, because their unusual morphology and light C （δ13C=-18 to -27） are unlike those of kimberlitic diamonds. However, the diamonds have now been found in situ in both the chromitites and the peridotites of ＂ophiolites＂ along the Yarlung-Zangbo suture （Tibet） and the Polar Urals （Yang et al., 2014）.

关键词： mINErALS PErIDOTITE DIAmONDS IGNEOUS rocks CrUST of the earth

Cooling History of mesozoic magmatism and Implications for Large-Scale Gold mineralization in the Jiaodong Peninsula, East China: Constraints from T-t Paths Determined by U-Pb Thermochronology of Zircon and Apatite

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Journal of Earth Science 2024年第3期35卷 878-889页

作者： Guangyan Zhou mingchun Song Long Li Yan Luo DGraham pearson Jianbo Zhou Zhengjiang Ding Xuefeng Yu Yingxin Song Jie Li Shiyong Li Faculty of Earth Sciences China University of GeosciencesWuhan 430074China Department of Earth&Atmospheric Sciences University of AlbertaEdmontonAlberta T6G 2E3Canada Hebei Key Laboratory of Strategic Critical mineral resources Hebei GEO UniversityShijiazhuang 050031China Shandong Provincial No.6 Exploration Institute of Geology and mineral resources Weihai 264209China College of Earth Sciences Jilin UniversityChangchun 130061China ministry of Natural resources Key Laboratory of Gold mineralization Processes and resources Utilization Key Laboratory of Metallogenic-Geologic Processes and Comprehensive Utilization of Minerals Resources in Shandong ProvinceShandong Institute of Geological SciencesJinan 250013China Shandong Nuclear Industry Geological Group 273 Yantai 264006China

The mesozoic intrusions of the Jiaodong Peninsula,eastern China,host giant gold *** the genesis of these deposits requires the determination of the source of the parental auriferous fluid and the timing of gold mineralization,which are strongly influenced by the cooling/uplift histories of the hosting *** performed an integrated U-Pb geochronology study on both zircon and apatite from four major magmatic episodes of the Jiaodong *** zircon and apatite U-Pb ages are 156.9±1.2 and 137.2±2.4 ma for the Linglong intrusion,129.9±1.0 and 125.0±3.8 ma for the Qujia intrusion,119.5±0.7 and 117.2±1.8 ma for the Liulinzhuang intrusion,118.6±1.0 and 111.6±1.6 ma for the Nansu intrusion,*** coupled zircon and apatite data of these granitoids indicate a slow cooling rate(11.9°C/ma)in the Late Jurassic,and rapid uplift and cooling(35.8-29.2°C/ma)in the Early *** dramatically increased uplift and cooling period in the Early Cretaceous are contemporaneous with large-scale gold mineralization in the Jiaodong *** implies that thermal upwelling of asthenosphere and related tectonic extension played an important role in gold remobilization and precipitation.

关键词： magmatism geochronology zircon apatite gold deposits Jiaodong Peninsula

Impaired swallowing mechanics of post radiation therapy head and neck cancer patients: A retrospective videofluoroscopic study

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World Journal of radiology 2016年第2期8卷 192-199页

作者： William G pearson Jr Alisa A Davidoff Zachary m Smith Dorothy E Adams Susan E Langmore Department of Cellular Biology and Ana-tomy Medical College of Georgia at Georgia Regents University Department of Otolaryngology Medical College of Georgia at Georgia Regents University Sargent College Boston University Department of Otolaryngology Head and Neck Surgery Boston University School of Medicine

AIm: To determine swallowing outcomes and hyolaryngeal mechanics associated with post radiation therapy head and neck cancer(rt HNC) patients using videofluoroscopic swallow studies. mETHODS: In this retrospective cohort study, video-fluoroscopic images of rt HNC patients(n = 21) were compared with age and gender matched controls(n = 21). Penetration-aspiration of the bolus and bolus residue were measured as swallowing outcome variables. Timing and displacement measurements of the anterior and posterior muscular slings elevating the hyolaryngeal complex were acquired. Coordinate data of anatomical landmarks mapping the action of the anterior muscles(suprahyoid muscles) and posterior muscles(long pharyngeal muscles) were used to calculate the distance measurements, and slice numbers were used to calculate time intervals. Canonical variate analysis with post-hoc discriminant function analysis was performed on coordinate data to determine multivariate mechanics of swallowing associated with treatment. Pharyngeal constriction ratio(PCr) was also measured to determine if weak pharyngeal constriction is associated with post radiation ***: The rt HNC group was characterized by poor swallowing outcomes compared to the control group in regards to: Penetration-aspiration scale(P rmalized residue ratio scale(NrrS) for the valleculae(P = 0.002) and NrrS for the piriform sinuses(P = 0.003). Timing and distance measurements of the anterior muscular sling were not significantly different in the two groups, whereas for the PmS time of displacement was abbreviated(P = 0.002) and distance of excursion was reduced(P = 0.02) in the rt HNC group. A canonical variate analysis shows a significant reduction in pharyngeal mechanics in the rt HNC group(P r was significantly higher in the test group than the control group(P = 0.0001) indicating reduced efficiency in pharyngeal clearance. CONCLUSION: Using videofluoroscopy, this study shows rt HNC pati

关键词： Swallow mechanics Post radiation Head and neck cancer Fluoroscopy Anatomy

Connexin 43 hemichannels protect bone loss during estrogen deficiency

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Bone research 2019年第2期7卷 183-194页

作者： Liang ma rui Hua Yi Tian Hongyun Cheng roberto Jose Fajardo Joseph J. pearson Teja Guda Daniel Brian Shropshire Sumin Gu Jean X. Jiang Department of Orthopaedics Jinan Central Hospital Affiliated to Shandong UniversityJinanShandongChina Department of Biochemistry and Structural Biology UT Health San AntonioSan AntonioTX 78229USA Department of Orthopedics UT Health San AntonioSan AntonioTX 78229USA Department of Biomechanical Engineering University of Texas at San AntonioSan AntonioTX 78249USA

Estrogen deficiency in postmenopausal women is a major cause of bone loss,resulting in osteopenia,osteoporosis,and a high risk for bone *** 43 (Cx43) hemichannels (HCs) in osteocytes play an important role in osteocyte viability,bone formation,and *** showed here that estrogen deficiency reduced Cx43 expression and HC *** determine if functional HCs protect osteocytes and bone loss during estrogen deficiency,we adopted an ovariectomy model in wild-type (WT) and two transgenic Cx43 mice:r76W (dominant-negative mutant inhibiting only gap junction channels) and Cx43 Δ130–136 (dominant-negative mutant compromising both gap junction channels and HCs).The bone mineral density (BmD),bone structure,and histomorphometric changes of cortical and trabecular bones after ovariectomy were *** results showed that the Δ130–136 transgenic cohort had greatly decreased vertebral trabecular bone mass compared to WT and r76W mice,associated with a significant increase in the number of apoptotic osteocyte and empty ***,osteoclast surfaces in trabecular and cortical bones were increased after ovariectomy in the r76W and WT mice,respectively,but not in Δ130–136 *** data demonstrate that impairment of Cx43 HCs in osteocytes accelerates vertebral trabecular bone loss and increase in osteocyte apoptosis,and further suggest that Cx43 HCs in osteocytes protect trabecular bone against catabolic effects due to estrogen deficiency.

关键词： hemichannels protect estrogen deficiency