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Effects of A-site nonstoichiometry on oxide ion conduction in 0.94Bi_(0.5)Na_(0.5)TiO_(3)-0.06BaTiO_(3) ceramics

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Journal of Advanced Dielectrics 2016年第2期6卷 70-78页

作者： Sasiporn prasertpalichat Whitney Schmidt david p.Cann Materials Science School of Mechanical Industrial and Manufacturing Engineering Oregon State UniversityCorvallisOR 97331USA

Lead free 0.94(Bi_(0.5)Na_(0.5))TiO_(3)-0.06BaTiO_(3)ceramics were prepared by conventional solid-state mixed oxide route with the A-site stoichiometry modified to incorporate donor-doping(through Bi-excess)and acceptor-doping(through Na-excess).Both stoichiometric and nonstoichiometric ceramics exhibited a single perovskite phase with pseudo-cubic symmetry.A significant improvement in the dielectric properties was observed in Bi-excess compositions and a deterioration in the dielectric properties was observed in Na-excess *** spectroscopy was utilized to analyze the effects of A-site nonstoichiometry on conduction *** with Bi-excess resulted in an electrically homogeneous microstructure with an increase in resistivity by3-4 orders of magnitude and an associated activation energy of 1.57 eV which was close to half of the optical *** contrast,an electrically heterogeneous microstructure was observed in both the stoichiometric and Na-excess *** addition,the Na-excess compositions exhibited low resistivities(ρ-10^(3)Ω-cm)with characteristic peaks in the impedance data comparable to the recent observations of oxide ion conduction in(Bi_(0.5)Na_(0.5))TiO_(3).Long term annealing studies were also conducted at 800℃to identify changes in crystal structure and electrical *** results of this study demonstrates that the dielectric and electrical properties of 0.94(Bi_(0.5)Na_(0.5))TiO_(3)-0.06BaTiO_(3)ceramics are very sensitive to Bi/Na stoichiometry.

关键词： A-site nonstoichiometry oxide ion conduction lead free BNT-BT ceramics impedance spectroscopy ceramics.

Status of Cry1Ac and Cry2Ab2 resistance in field populations of Helicoverpa zea in Texas, USA

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Insect Science 2022年第2期29卷 487-495页

作者： JoséC.Santiago González david L.Kerns Graham p.Head Fei Yang Department of Entomology Texas A&M UniversityCollege StationTexasUSA Bayer Crop Science St.LouisMissouriUSA

Helicoverpa zea is a major target pest of Bt corn and Bt ***-evolved resistance of *** to Cry1 and Cry2 proteins has been widely reported in the United *** the frequency of resistance alleles in a target insect is critical for Bt resistance *** multiple cases of practical resistance to Cry proteins having been documented in ***,there are no data on the current status of alleles conferring resistance to Cry1Ac and Cry2Ab2 in field populations of this *** 2018‒2019,a total of 106 F2 families for Cry1Ac and 120 F2 families for Cry2Ab2 were established using mass mating and light trap *** screened 13,568 and 15,360 neonates using a discriminatory dose of Cry1Ac and Cry2Ab2,*** results showed that 93.4%and 35.0%of the F2 families could survive on the discriminatory dose of Cry1Ac and Cry2Ab2,*** estimated resistance allele frequency for Cry1Ac in *** ranged from 0.4150 to 0.4975 and for Cry2Ab2 ranged from 0.1097 and *** data indicate that the frequency of alleles conferring resistance to Cry1 and Cry2 proteins in *** in Texas are *** addition,our data suggest the resistance to Cry1Ac and Cry2Ab2 in the screened families of *** varies from recessive to *** information in this study provides precise estimates of Cry resistance allele frequencies in *** and increases our understanding of the risks to the sustainability of Bt crops.

关键词： allele frequency Bacillus thuringiensis CrylAc Cry2Ab2 Helicoverpa zea resistance

Artificial generation of representative single Li-ion electrode particle architectures from microscopy data

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npj Computational Materials 2021年第1期7卷 948-963页

作者： Orkun Furat Lukas petrich Donal p.Finegan david Diercks Francois Usseglio-Viretta Kandler Smith Volker Schmidt Institute of Stochastics Ulm University89069 UlmGermany National Renewable Energy Laboratory GoldenCOUSA Colorado School of Mines GoldenCOUSA

Accurately capturing the architecture of single lithium-ion electrode particles is necessary for understanding their performance limitations and degradation mechanisms through multi-physics *** is drawn from multimodal microscopy techniques to artificially generate LiNi_(0.5)Mn_(0.3)Co_(0.2)O_(2) particles with full sub-particle grain *** representations of particle architectures are derived from X-ray nano-computed tomography data supporting an‘outer shell’model,and sub-particle grain representations are derived from focused-ion beam electron backscatter diffraction data supporting a‘grain’model.A random field model used to characterize and generate the outer shells,and a random tessellation model used to characterize and generate grain architectures,are combined to form a multi-scale model for the generation of virtual electrode particles with fullgrain *** work demonstrates the possibility of generating representative single electrode particle architectures for modeling and characterization that can guide synthesis approaches of particle architectures with enhanced performance.

关键词： electrode particle outer

Regeneration patterns of key pine species in a mixed-pine forest indicate a positive effect of variable retention harvesting and an increase in recruitment with time

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Forest Ecosystems 2020年第4期7卷 659-671页

作者： priscilla A.Nyamai p.Charles Goebel R.Gregory Corace III david M.Hix Natural Resources Management program Grand Valley State University1 Campus DrAllendaleMI 49401USA. Department of Forest Rangelandand Fire SciencesUniversity of Idaho875 Perimeter Drive MS 1133MoscowID 83844USA. Alpena-Montmorency Conservation District 1900 M-32 WAlpenaMI 49707USA. School of Environment and Natural Resources The Ohio State University2021 Coffey RoadColumbusOH 43210USA.

Background:Many fire-dependent forests have experienced significant declines in species,structural,and functional *** changes are attributed in part to traditional management approaches that were dominated by even-aged regeneration methods such as *** retention harvesting(VRH)is an ecologically based forestry practice that involves retention of some mature overstory trees and other biological structures in the postharvest stand to emulate the effects of natural disturbance *** this study,we examined the effect of a VRH treatment on recruitment of historically dominant pine species and understory vegetation twoand six years after its implementation in a naturally regenerated mixed pine forest in the Upper peninsula of Michigan,***:We found greater regeneration of red pine(pinus resinosa L.)and eastern white pine(pinus strobus L.)in VRH stands compared to the unharvested *** red pine recruitment was very low during the first 2 years,both species increased significantly from year two to year *** responses for the two species did not differ significantly between the aggregated and dispersed retention *** also found high recruitment of deciduous tree species,consisting primarily of sprouts,and red pine exhibited a negative correlation with these ***,time,and the interaction of treatment and time were significant factors in red pine *** had a strong effect on the understory vegetation,with significant decreases in shrubs and ferns over ***:The results suggest that VRH enhanced recruitment of red pine and eastern white pine and that this recruitment increased with *** identify competition from sprouts and unfavorable seedbed conditions as the main factors that limited recruitment of red pine during the first 2 *** reduce competing vegetation and improve seedbed conditions,we suggest following the VRH with a prescribed fire,mechanically removing s

关键词： Variable retention harvesting Aggregated retention Dispersed retention Mixed-pine forest pinus resinosa pinus strobus

Quantitative analysis of the impact of droughts and floods on internal wars in China over the last 500 years

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Science China Earth Sciences 2017年第12期60卷 2078-2088页

作者： Harry F.LEE david D.ZHANG pEI Qing JIA Xin Ricci p.H.YUE Department of Geography and International Center for China Development Studies The University of Hong Kong School of Geographical Sciences Guangzhou University Department of Social Sciences The Education University of Hong Kong School of Geographic and Oceanographic Sciences Nanjing University

Although many large-N quantitative studies have evidenced the adverse effects of climatic extremes on social stability in China during the historical period, most of them rely on temperature and precipitation as major explanatory variables, while the influence of floods and droughts on social crises is rarely measured. Furthermore, a comparison of the climate-society nexus among different geographic regions and at different temporal scales is missing in those studies. To address this knowledge gap,this study examines quantitatively the influence of floods and droughts on internal wars in three agro-ecological(rice, wheat,and pastoral) regions in China in AD1470–1911. poisson regression and wavelet transform coherence analyses are applied to allow for the non-linear and non-stationary nature of the climate-war nexus. Results show that floods and droughts are significant in driving internal wars in historical China, but are characterized by strong regional variation. In the rice region, floods trigger internal wars at the inter-annual and multi-decadal time scales. In the wheat region, both floods and droughts cause internal wars at the inter-annual and multi-decadal time scales. In the pastoral region, internal wars are associated with floods only at the multi-decadal time scale. In addition, the multi-decadal coherence between hydro-climatic extremes and internal wars in all three of the agro-ecological regions is only significant in periods in which population density is increasing or the upper limit of regional carrying capacity is being reached. The above results imply that the climate-war nexus is mediated by regional geographic factors such as physical environmental setting and population pressure. Hence, we encourage researchers who study the historical human-climate relationship to boil down data according to geographic regions in the course of statistical analysis and to examine each region individually in follow-up studies.

关键词： Floods and droughts Climatic extremes Internal wars Wars Social stability Ming-Qing period

Targeting non-coding RNAs to overcome cancer therapy resistance

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Signal Transduction and Targeted Therapy 2022年第5期7卷 1447-1466页

作者： BaoQing Chen Mihnea p.Dragomir Chen Yang Qiaoqiao Li david Horst George A.Calin Department of Radiation Oncology State Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineSun Yat-sen University Cancer CenterGuangzhouGuangdong 510060China Institute of pathology Charité-Universitätsmedizin Berlincorporate member of Freie Universität BerlinHumboldt-Universität zu Berlin and Berlin Institute of HealthBerlin 10117Germany Berlin Institute of Health Anna-Louisa-Karsch-Straße 210178 BerlinGermany German Cancer Consortium(DKTK) Partner Site BerlinGerman Cancer Research Center(DKFZ)69210 HeidelbergGermany Department of Translational Molecular pathology The University of Texas MD Anderson Cancer CenterHoustonTX 77030USA Center for RNA Interference and Non-Coding RNAs The University of Texas MD Anderson Cancer CenterHoustonTX 77030USA

It is now well known that non-coding RNAs(ncRNAs),rather than protein-coding transcripts,are the preponderant RNA ***,particularly microRNAs(miRNAs),long non-coding RNAs(lncRNAs),and circular RNAs(circRNAs),are widely appreciated as pervasive regulators of multiple cancer hallmarks such as proliferation,apoptosis,invasion,metastasis,and genomic *** recent discoveries in cancer therapy,resistance to chemotherapy,radiotherapy,targeted therapy.

关键词： chemotherapy metastasis RNAs

Small-Scale Mineralogical Heterogeneity from Variations in phase Assemblages in the Transition Zone and D" Layer predicted by Convection Modelling

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Journal of Earth Science 2011年第2期22卷 160-168页

作者： Arie p van den Berg david A Yuen Michael H G Jacobs Maarten V de Hoop Earth Sciences Department Utrecht University Department of Geology and Geophysics and Minnesota Supercomputing Institute University of MinnesotaMinneapolisMN 55415USA Institut für Metallurgie TU ClausthalClausthal-ZellerfeldGermany Department of Mathematics and Center of Applied and Computational Mathematics Purdue UniversityWest LafayetteINUSA

Small-scale heterogeneity in the deep mantle is concentrated in the upper-mantle transition zone （TZ）, in the depth range 410-660 km and also at the bottom 250 km D＂ region. This encourages a more detailed investigation of the potential for seismic reflectivity imaging by modelling heterogeneous structures in mantle convection models including phase transitions of the TZ and D＂ regions. We applied finite elements with variable spacing near the boundary layers in 2-D cylindrical geometry that allow for sufficient spatial resolution. We investigated several models including an extended Boussinesq （EBA） model, focused on the D＂ region, and a compressible （ALA） model for the TZ region. The results for the D＂ region show typical lens-shaped structures of post-perovskite （ppV） embedded in the perovskite （pV） background mantle, where the thickness of the lenses, at 200-400 km, strongly depends on the Clapeyron slope of the pV-ppV transition. A second phase transition （double crossing） occurs in case the core temperature is higher than the intercept temperature Ti. Our phase-dependent rheology results in contrasting effective viscosity between pV and ppV. Our model results reveal a distinctly clear mechanical weakening of the ppV lenses with about an order of magnitude lower viscosity. The shear wave-speed distributions computed from our convection results are strongly correlated with the heterogeneous distribution of the mineral phase. Gradients in the seismic wave-speed that are the target of seismological reflectivity imaging are clearly revealed. The wave-speed results show a clear resolution of the top and bottom interfaces of the ppV lenses. Our ALA model for the TZ is based on a thermodynamical model for the magnesium end- member of an olivine-pyroxene mantle. The model predicts a much more complex distribution of mineral phases, compared to our D＂ results, in agreement with the greater number of mineral phases involved in the olivine-pyroxene phase diagram for the p

关键词： mantle convection phase transition post-perovskite mineralogical heterogeneity.

A candidate targeting molecule of insulin-like growth factor-Ⅰ receptor for gastrointestinal cancers

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World Journal of Gastroenterology 2010年第46期16卷 5779-5789页

作者： Yasushi Adachi Hiroyuki Yamamoto Hirokazu Ohashi Takao Endo david p Carbone Kohzoh Imai Yasuhisa Shinomura First Department of Internal Medicine Sapporo Medical University Department of Internal Medicine Sapporo Shirakabadai Hospital Vanderbilt-Ingram Cancer Center and Departments of Medicine and Cell Biology Vanderbilt University

Advances in molecular research in cancer have brought new therapeutic strategies into clinical *** new group of targets is tyrosine kinase receptors,which can be treated by several strategies,including small molecule tyrosine kinase inhibitors(TKIs) and monoclonal antibodies(mAbs).Aberrant activation of growth factors/receptors and their signal pathways are required for malignant transformation and progression in gastrointestinal(GI) *** concept of targeting specif ic carcinogenic receptors has been validated by successful clinical application of many new *** I insulin-like growth factor(IGF) receptor(IGF-IR) signaling potently stimulates tumor progression and cellular differentiation,and is a promising new molecular target in human *** this review,we focus on this promising therapeutic target,*** IGF/IGF-IR axis is an important modifier of tumor cell proliferation,survival,growth,and treatment sensitivity in many malignant diseases,including human GI *** studies demonstrated that downregulation of IGF-IR signals reversed the neoplastic phenotype and sensitized cells to anticancer *** results were mainly obtained through our strategy of adenoviruses expressing dominant negative IGF-IR(IGF-IR/dn) against gastrointestinal cancers,including esophagus,stomach,colon,and *** also summarize a variety of strategies to interrupt the IGFs/IGF-IR axis and their preclinical *** mAbs and TKIs targeting IGF-IR have entered clinical trials,and early results have suggested that these agents have generally acceptable safety profiles as single *** summarize the advantages and disadvantages of each strategy and discuss the merits/demerits of dual targeting of IGF-IR and other growth factor receptors,including Her2 and the insulin receptor,as well as other alternatives and possible drug ***,IGF-IR might be a candidate for a molecular therapeutic target in human GI carcino

关键词： Dominant negative Gastrointestinal cancer Insulin like growth factor-I receptor Monoclonal anti-body Tyrosine kinase inhibitor

postoperative visual performance with a bifocal and trifocal diffractive intraocular lens during a 1-year follow-up

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International Journal of Ophthalmology(English edition) 2017年第10期10卷 1528-1533页

作者： peter Mojzis Lucia Kukuckova Katarina Majerova peter Ziak david p.pi?ero premium Clinic Eye Department of Regional Hospital in Havlickuv Brod Eye Clinic of Jessnius Faculty of Medicine Department of Optics Pharmacology and AnatomyUniversity of Alicante

AIM：To evaluate and compare the clinical outcomes with a diffractive bifocal and trifocal intraocular lens（IOL）during a 12-month ***：prospective comparative study including75 eyes of 38 patients（44-70y）undergoing uneventful cataract *** patient was randomly assigned to one type of IOL,bifocal（35 eyes）or trifocal（40 eyes）.Visual,refractive,and contrast sensitivity changes were evaluated in a 12-month *** binocular defocus curve was also measured at 12mo ***：No statistically significant differences between groups were found in postoperative uncorrected and corrected distance visual acuities（p≥0.276）.postoperative corrected near visual acuity（33 cm）was significantly better in the trifocal group during all follow-up（p≤0.004）as well as 6-month uncorrected near（p=0.008）and distancecorrected near visual acuities（p=0.016）（33/40 cm）.Significantly better uncorrected intermediate and distance corrected-intermediate visual acuity were found during all follow-up in the trifocal group（p〈0.001）,which was consistent with differences among groups in binocular defocus *** among groups in contrast sensitivity were minimal,being only significant at 6 months for some low to medium spatial frequencies（p≤0.006）.CONCLUSION：Bifocal and trifocal diffractive IOLs are able to provide an effective visual restoration which is maintained during a 12-month follow-up,with a clear benefit of the trifocal IOL for the intermediate vision.

关键词： trifocal intraocular lens bifocal intraocular lens defocus curve contrast sensitivity cataract surgery