Colossal permittivity(CP)materials,particularly co-doped TiO_(2) ceramics,have garnered significant attention for their potential in high-performance ceramic capacitors.However,understanding the origin of CP remains a...Colossal permittivity(CP)materials,particularly co-doped TiO_(2) ceramics,have garnered significant attention for their potential in high-performance ceramic capacitors.However,understanding the origin of CP remains a challenge,with the role of doping ratios between acceptor and donor ions largely underexplored.This study addresses this gap by systematically investigating the effects of Ga^(3+)concentrations on the microstructure and CP of Ga_(y)Nb_(0.025)Ti_(0.975-y)O_(2),prepared via the solid-state reaction method.The sintered ceramics exhibited a dense rutile TiO_(2) phase with increasing grain sizes and oxygen vacancies.Notably,CP values as high as 10^(5) were achieved at Ga^(3+)/Nb^(5+)ratio<1.0.Optimal dielectric properties were observed at Ga^(3+)/Nb^(5+)=1.0,yielding a CP of 6.4×10^(4) and a loss tangent<0.03,surpassing the performance of many existing CP materials.Impedance spectroscopy revealed distinct electrical heterogeneity,with conductive grains and highly resistive grain boundaries with activation energies>1.0 eV.Ceramics with 5%Ga^(3+) doping showed diminished CP due to the absence of semiconducting grains.The findings suggest that CP originates from the internal barrier layer capacitor.This study not only elucidates the crucial role of doping ratios in tailoring CP but also establishes a pathway for developing advanced dielectric materials with superior performance for ceramic capacitors.展开更多
Human pluripotent stem cells(hPSCs)can in theory give rise to any hematopoietic lineages,thereby offering opportunities for disease modeling,drug screening and cell therapies.However,gaps in our knowledge of the signa...Human pluripotent stem cells(hPSCs)can in theory give rise to any hematopoietic lineages,thereby offering opportunities for disease modeling,drug screening and cell therapies.However,gaps in our knowledge of the signaling requirements for the specification of human hematopoietic stem/progenitor cells(HSPCs),which lie at the apex of all hematopoietic lineages,greatly limit the potential of hPSC in hematological research and application.Transcriptomic analysis reveals aberrant regulation of WNT signaling during maturation of hPSC-derived hematopoietic progenitor cells(hPSC-HPCs),which results in higher mitochondria activity,misregulation of HOX genes,loss of self-renewal and precocious differentiation.These defects are partly due to the activation of the WNT target gene CDX2.Late-stage WNT inhibition improves the yield,self-renewal,multilineage differentiation,and transcriptional and metabolic profiles of hPSC-HPCs.Genome-wide mapping of transcription factor(TF)accessible chromatin reveals a significant overrepresentation of myeloid TF binding motifs in hPSC-HPCs,which could underlie their myeloid-biased lineage potential.Together our findings uncover a previously unappreciated dynamic requirement of the WNT signaling pathway during the specification of human HSPCs.Modulating the WNT pathway with small molecules normalizes the molecular differences between hPSC-HPCs and endogenous hematopoietic stem cells(HSCs),thereby representing a promising approach to improve the differentiation and function of hPSC-HPCs.展开更多
We describe a fiber optic hydrophone array system that could be used for underwater acoustic surveillance applications （e.g. military, counter terrorist, and customs authorities in protecting ports and harbors）, off...We describe a fiber optic hydrophone array system that could be used for underwater acoustic surveillance applications （e.g. military, counter terrorist, and customs authorities in protecting ports and harbors）, offshore production facilities or coastal approaches as well as various marine applications. In this paper, we propose a new approach to underwater sonar systems using the voltage-controlled liquid crystals and simple multiplexing method. The proposed method permits measurement of sound under water at multiple points along an optical fiber using the low cost components and standard single mode fiber, without complex interferometric measurement techniques, electronics or demodulation software.展开更多
Dear Editor,Metabolically induced cancer heterogeneity creates a large source of novel potential targets towards an enhanced therapeutic window alone and in combination with classic chemo-and radiotherapy[1,2].This is...Dear Editor,Metabolically induced cancer heterogeneity creates a large source of novel potential targets towards an enhanced therapeutic window alone and in combination with classic chemo-and radiotherapy[1,2].This is of particular interest for non-small cell lung cancer(NSCLC),which accounts for more than 80%of all lung tumor types characterized by limited responses to current treatment options[3–5].展开更多
基金funded by the National Science,Research,and Innovation Fund(NSRF)and the Fundamental Fund of Khon Kaen Universitypartially supported by the Research of Khon Kaen Universitythe Thailand Graduate Institute of Science and Technology(TGIST)for his Ph.D.scholarship[Grant Number SCA-CO-2558-1033-TH].
文摘Colossal permittivity(CP)materials,particularly co-doped TiO_(2) ceramics,have garnered significant attention for their potential in high-performance ceramic capacitors.However,understanding the origin of CP remains a challenge,with the role of doping ratios between acceptor and donor ions largely underexplored.This study addresses this gap by systematically investigating the effects of Ga^(3+)concentrations on the microstructure and CP of Ga_(y)Nb_(0.025)Ti_(0.975-y)O_(2),prepared via the solid-state reaction method.The sintered ceramics exhibited a dense rutile TiO_(2) phase with increasing grain sizes and oxygen vacancies.Notably,CP values as high as 10^(5) were achieved at Ga^(3+)/Nb^(5+)ratio<1.0.Optimal dielectric properties were observed at Ga^(3+)/Nb^(5+)=1.0,yielding a CP of 6.4×10^(4) and a loss tangent<0.03,surpassing the performance of many existing CP materials.Impedance spectroscopy revealed distinct electrical heterogeneity,with conductive grains and highly resistive grain boundaries with activation energies>1.0 eV.Ceramics with 5%Ga^(3+) doping showed diminished CP due to the absence of semiconducting grains.The findings suggest that CP originates from the internal barrier layer capacitor.This study not only elucidates the crucial role of doping ratios in tailoring CP but also establishes a pathway for developing advanced dielectric materials with superior performance for ceramic capacitors.
基金supported by CIRM fellowshipssupported by grants from the G.Harold and Leila Y.Mathers Charitable Foundation,The California Institute of Regenerative Medicine,Ellison Medical Foundation,and The Leona M.and Harry B.Helmsley Charitable Trust grant#2012-PG-MED002supported by the KAUST Office of Sponsored Research(OSR)under Award No.BAS/1/1080-01(ML),URF/1/4716-01(ML)and KAUST Center of Excellence for Smart Health(KCSH)award number 5932.
文摘Human pluripotent stem cells(hPSCs)can in theory give rise to any hematopoietic lineages,thereby offering opportunities for disease modeling,drug screening and cell therapies.However,gaps in our knowledge of the signaling requirements for the specification of human hematopoietic stem/progenitor cells(HSPCs),which lie at the apex of all hematopoietic lineages,greatly limit the potential of hPSC in hematological research and application.Transcriptomic analysis reveals aberrant regulation of WNT signaling during maturation of hPSC-derived hematopoietic progenitor cells(hPSC-HPCs),which results in higher mitochondria activity,misregulation of HOX genes,loss of self-renewal and precocious differentiation.These defects are partly due to the activation of the WNT target gene CDX2.Late-stage WNT inhibition improves the yield,self-renewal,multilineage differentiation,and transcriptional and metabolic profiles of hPSC-HPCs.Genome-wide mapping of transcription factor(TF)accessible chromatin reveals a significant overrepresentation of myeloid TF binding motifs in hPSC-HPCs,which could underlie their myeloid-biased lineage potential.Together our findings uncover a previously unappreciated dynamic requirement of the WNT signaling pathway during the specification of human HSPCs.Modulating the WNT pathway with small molecules normalizes the molecular differences between hPSC-HPCs and endogenous hematopoietic stem cells(HSCs),thereby representing a promising approach to improve the differentiation and function of hPSC-HPCs.
文摘We describe a fiber optic hydrophone array system that could be used for underwater acoustic surveillance applications （e.g. military, counter terrorist, and customs authorities in protecting ports and harbors）, offshore production facilities or coastal approaches as well as various marine applications. In this paper, we propose a new approach to underwater sonar systems using the voltage-controlled liquid crystals and simple multiplexing method. The proposed method permits measurement of sound under water at multiple points along an optical fiber using the low cost components and standard single mode fiber, without complex interferometric measurement techniques, electronics or demodulation software.
基金supported by the Swiss National Science Foundation,Switzerland(grant 320030_176088 to Johannes Häberle)the Wolfermann-Nägeli-Stiftung,Switzerland(grant 2020/28 to Martin Pruschy).+2 种基金supported by the Research Council of Norway(NOR-OPENSCREEN 245922/F50)supported by The Fundación Ramón Areces(grant CIVP20A6610)supported by a grant from European Union’s Framework Program for Research and Innovation Horizon 2020(2014-2020)under Marie Skłodowska-Curie(Grant Agreements No.860245)(ITN THERADNET)to Marvin Kreuzer and Martin Pruschy.
文摘Dear Editor,Metabolically induced cancer heterogeneity creates a large source of novel potential targets towards an enhanced therapeutic window alone and in combination with classic chemo-and radiotherapy[1,2].This is of particular interest for non-small cell lung cancer(NSCLC),which accounts for more than 80%of all lung tumor types characterized by limited responses to current treatment options[3–5].
