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Gel casting of PZt pillar arrays for high frequency ultrasonic medical imaging applications

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Gel casting of PZT pillar arrays for high frequency ultrason...

Co-Mn-Ni-O_2系材料阻温特性与频率关系的研究

2011 world Congress on Engineering and technology(CEt 2011)

作者： H.Hughes C.Meggs t.w.button School of Metallurgy and Materials University of Birmingham

In this paper we report ultrafine PZt （lead zirconate titanate） pillar arrays for high frequency ultrasonic transducers application by gel casting fabricated using a water soluble resin as a gel *** effect of the amount of hardener addition and ceramic solids loading on the rheological properties and the effect of resin content on the mechanical strength has been *** green strengths of 36.8 MPa have been obtained from gel cast PZt green bodies with 45 vol % solids loading containing 20 wt% of epoxy resin in the premixed *** structures with lateral features down to 2 μm and aspect ratios up to 30 have been demoulded without *** PZt samples are homogenous with low porosity and also show good piezoelectric properties.

关键词： gel casting PZt ultrasonic transducer

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电子元件与材料 2007年第7期26卷 53-56页

作者：康雪雅王天雕 D．Zhang t．w．button 中国科学院新疆理化技术研究所新疆乌鲁木齐830011 Functional Materials Group IRC in Materials Processing School of Engineering University of Birminghan B 15 2TT UK

通过XRD、SEM分析和变温、变频条件下的lgρ-t测量,对Co-Mn-Ni-O2系热敏材料的lgρ-t特性与频率f的关系进行了研究。结果表明:CoMn1.4Ni0.6O4尖晶石型氧化物热敏电阻材料的阻温特性在0.1~1MHz和–70^+100℃,发生了PtC向NtC的转变,且转... 详细信息

通过XRD、SEM分析和变温、变频条件下的lgρ-t测量,对Co-Mn-Ni-O2系热敏材料的lgρ-t特性与频率f的关系进行了研究。结果表明:CoMn1.4Ni0.6O4尖晶石型氧化物热敏电阻材料的阻温特性在0.1~1MHz和–70^+100℃,发生了PtC向NtC的转变,且转变点的温度(–70~–10℃)和f(0.1~1MHz)与材料电阻率ρ有关。根据电导率σ和载流子浓度n、载流子迁移率μ之间的关系,用小极子跳跃导电理论对上述现象作了解释。

关键词：电子技术频率热敏电阻 NtC PtC 小板子

Growth in Infinite Groups of Infinite Subsets

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Algebra Colloquium 2015年第2期22卷 333-348页

作者： J.O. button Selwyn College University of Cambridge Cambridge CB3 9DQ UK

Given an infinite group G, we consider the finitely additive invariant measure defined on finite unions of cosets of finite index subgroups. we show that this shares many properties with the size of subsets of a finite group, for instance we can obtain equivalent results on the Ruzsa distance and product free sets. In particular, if G has infinitely many finite index subgroups, then it has subsets S of measure arbitrarily close to 1/2 with square S2 having measure less than 1. we also examine properties of the Ruzsa distance on the set of finite index subgroups of an infinite group, whereupon it becomes a genuine metric.

关键词： group product set, Ruzsa distance

A novel method for clustering cellular data to improve classification

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Neural Regeneration Research 2025年第9期20卷 2697-2705页

作者： Diek w.wheeler Giorgio A.Ascoli Center for Neural Informatics Structures&PlasticityKrasnow Institute for Advanced Study Bioengineering Department Volgenau School of Engineering George Mason University FairfaxVAUSA

Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subsets via hierarchical clustering,but objective methods to determine the appropriate classification granularity are *** recently introduced a technique to systematically identify when to stop subdividing clusters based on the fundamental principle that cells must differ more between than within *** we present the corresponding protocol to classify cellular datasets by combining datadriven unsupervised hierarchical clustering with statistical *** general-purpose functions are applicable to any cellular dataset that can be organized as two-dimensional matrices of numerical values,including molecula r,physiological,and anatomical *** demonstrate the protocol using cellular data from the Janelia MouseLight project to chara cterize morphological aspects of neurons.

关键词： cellular data clustering dendrogram data classification Levene's one-tailed statistical test unsupervised hierarchical clustering

Sources of transcription variation in Plasmodium falciparum

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Journal of Genetics and Genomics 2022年第10期49卷 965-974页

作者： Lindsey B.turnbull Katrina A.button-Simons Nestor Agbayani Michael t.Ferdig Department of Pediatrics Indiana University School of MedicineIndianapolisIN 46202USA Department of Biological Sciences Eck Institute for Global HealthUniversity of Notre DameNotre DameIN 46556USA Rush School of Medicine ChicagoIL 60612USA

Variation in transcript abundance can contribute to both short-term environmental response and long-term evolutionary *** studies are designed to assess differences in mean transcription levels and do not consider other potentially important and confounding sources of transcriptional *** quantification of variation sources will improve our ability to detect and identify the mechanisms that contribute to genome-wide transcription changes that underpin adaptive *** quantify innate levels of expression variation,we measured m RNA levels for more than 5000 genes in the malaria parasite,Plasmodium falciparum,among clones derived from two parasite strains across biologically and experimentally replicated *** a mixed effects model,we partitioned the total variation among four sources—between strain,within strain,environmental batch effects,and stochastic *** found 646 genes with significant variation attributable to at least one of these *** genes were categorized by their predominant variation source and further examined using gene ontology enrichment analysis to associate function with each source of *** with environmental batch effect and within strain transcript variation may contribute to phenotypic plasticity,while genes with between strain variation may contribute to adaptive responses and processes that lead to parasite strain-specific survival under varied conditions.

关键词： Expression variation Malaria transcription Cloning Microarray

Genistein:a possible solution for the treatment of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2903-2905页

作者： Karolina Pierzynowska Bartosz Karaszewski Grzegorz węgrzyn Department of Molecular Biology University of GdanskGdanskPoland Gdansk Polandand Department of Adult NeurologyFaculty of MedicineMedical University of GdanskGdanskPoland

Neurodegenerative diseases are defined as disorders resulting from the slow and progressive loss of function and eventual death of neural cells that result from the primary pathology of nervous *** can lead to severe nervous system dysfunction,eventually affecting multiple organs and *** hundred neurodegenerative diseases have been described,and owing to their prevalence,severity.

关键词： organs Alzheimer death

Glia-to-neuron reprogramming to the rescue?

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Neural Regeneration Research 2025年第5期20卷 1395-1396页

作者： Jack w.Hickmott Cindi M.Morshead Department of Surgery University of TorontoTorontoONCanada Donnelly Centre for Cellular and Biomolecular Research TorontoONCanada Institute of Biomedical Engineering University of TorontoTorontoONCanada the KItE Research Institute Toronto Rehabilitation InstituteUniversity Health NetworkTorontoONCanada

Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative *** brea kth rough discovery that induced pluripotent stem cells could be generated from adult mouse fibroblasts is powerful proof that cell fate can be *** exciting extension of the discovery of cell fate impermanence is the direct cellular reprogram ming hypothesis-that terminally differentiated cells can be reprogrammed into other adult cell fates without first passing through a stem cell state.

关键词： programming passing proof

Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 123-138页

作者： Chentong GAO Huiyu SUN Jianping GU w.M.HUANG College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics School of Mechanical and Aerospace Engineering Nanyang Technological University Jiangsu Key Laboratory of Advanced Structural Materials and Application technology School of Materials Science and EngineeringNanjing Institute of Technology

Currently, there are a limited number of dynamic models available for braided composite plates with large overall motions, despite the incorporation of three-dimensional(3D) braided composites into rotating blade components. In this paper, a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established. Based on Kirchhoff's plate assumptions, the displacement variables of the plate are expressed. By incorporating the braiding directions into the constitutive equation of the braided composites, the dynamic model of the plate considering braiding directions is obtained. the effects of the speeds, braiding directions, and braided angles on the responses of the plate with fixed-axis rotation and translational motion, respectively, are investigated. this paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions. It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications.

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toward three-dimensional in vitro models to study neurovascular unit functions in health and disease

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Neural Regeneration Research 2021年第11期16卷 2132-2140页

作者： tara M.Caffrey Emily B.button Jerome Robert Djavad Mowafaghian Center for Brain Health University of British ColumbiaVancouverBCCanada Department of Pathology University of British ColumbiaVancouverBCCanada Institute of Clinical Chemistry University Hospital of ZurichZurichSwitzerland

the high metabolic demands of the brain require an efficient vascular system to be coupled with neural activity to supply adequate nutrients and *** supply is coordinated by the action of neurons,glial and vascular cells,known collectively as the neurovascular unit,which temporally and spatially regulate local cerebral blood flow through a process known as neurovascular *** many neurodegenerative diseases,changes in functions of the neurovascular unit not only impair neurovascular coupling but also permeability of the blood-brain barrier,cerebral blood flow and clearance of waste from the *** order to study disease mechanisms,we need improved physiologicallyrelevant human models of the neurovascular *** towards modeling the cellular complexity of the neurovascular unit in vitro have been made using stem-cell derived organoids and more recently,vascularized organoids,enabling intricate studies of non-cell autonomous *** and design innovations in microfluidic devices and tissue engineering are progressing our ability to interrogate the *** advanced models are being used to gain a better understanding of neurodegenerative disease processes and potential *** innovation is required to build more physiologically-relevant models of the neurovascular unit encompassing both the cellular complexity and designed features to interrogate neurovascular unit functionality.

关键词： Alzheimer’s disease cerebrovasculature in vitro model neurodegeneration neurovascular unit