patterning

图案化
  • 文章类型: Journal Article
    学龄前儿童的数学知识发展较早,差异很大。当前的研究集中在两种遗传早期出现的认知技能上,它们可能是后期数学技能的重要预测因子(即,几何和算术):儿童对对象和数量之间抽象关系的理解,这通过他们的图案化技能和近似数字系统(ANS)来证明。儿童的图案技能,ANS,算术,几何图形,非语言智力(IQ),在4岁时评估执行功能(EF)技能,一年后,在5岁时再次评估了他们的算术和几何知识(N=113)。超越儿童在算术和几何方面的初步知识,以及IQ和EF,4岁时的图案技能和ANS唯一地预测了5岁时儿童的几何知识,但只有4岁时的图案唯一地预测了5岁时的算术能力。因此,虽然图案和ANS是相关的,它们在后来的几何和算术知识中不同地解释了变化。讨论了结果对早期数学理论和研究的影响。
    Preschoolers\' mathematics knowledge develops early and varies substantially. The current study focused on two ontogenetically early emerging cognitive skills that may be important predictors of later math skills (i.e., geometry and numeracy): children\'s understanding of abstract relations between objects and quantities as evidenced by their patterning skills and the approximate number system (ANS). Children\'s patterning skills, the ANS, numeracy, geometry, nonverbal intelligence (IQ), and executive functioning (EF) skills were assessed at age 4 years, and their numeracy and geometry knowledge was assessed again a year later at age 5 (N = 113). Above and beyond children\'s initial knowledge in numeracy and geometry, as well as IQ and EF, patterning skills and the ANS at age 4 uniquely predicted children\'s geometry knowledge at age 5, but only age 4 patterning uniquely predicted age 5 numeracy. Thus, although patterning and the ANS are related, they differentially explain variation in later geometry and numeracy knowledge. Results are discussed in terms of implications for early mathematics theory and research.
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  • 文章类型: Journal Article
    本研究旨在建立和优化使用热压花技术制造生物相容性聚合物ParyleneC的3D微结构的工艺。不同的工艺参数,如压花温度,压花力,脱模温度和速度,优化了脱模剂的使用,利用粘合剂微柱作为用例。为了增强与传统半导体制造技术的兼容性,ParyleneC的热压花是从常规的不锈钢基板到硅片平台。此外,此调整包括研究热压印工艺对嵌入ParyleneC中的金属层的影响,确保与先前演示的超薄Parylene印刷电路板(PCB)的兼容性。为了评估产生的微观结构,采用了表征方法的组合,包括光学显微镜(LM)和扫描电子显微镜(SEM),X射线衍射(XRD)X射线光电子能谱(XPS),和傅里叶变换红外光谱(FTIR)。这些方法提供了对形态学的全面见解,化学,考虑到与现有的ParyleneC图案化技术(如等离子蚀刻或激光烧蚀)相比的改进结果,开发的热压印方法产生了优越的结构完整性,其特征在于增加的特征分辨率和增强的侧壁光滑度。这些进步使得该方法特别适合于不同的应用,包括但不限于,传感器光学元件,医用可穿戴设备的粘合接口,和微流体系统。
    This study aims to establish and optimize a process for the fabrication of 3D microstructures of the biocompatible polymer Parylene C using hot embossing techniques. The different process parameters such as embossing temperature, embossing force, demolding temperature and speed, and the usage of a release agent were optimized, utilizing adhesive micropillars as a use case. To enhance compatibility with conventional semiconductor fabrication techniques, hot embossing of Parylene C was adapted from conventional stainless steel substrates to silicon chip platforms. Furthermore, this adaptation included an investigation of the effects of the hot embossing process on metal layers embedded in the Parylene C, ensuring compatibility with the ultra-thin Parylene printed circuit board (PCB) demonstrated previously. To evaluate the produced microstructures, a combination of characterization methods was employed, including light microscopy (LM) and scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FTIR). These methods provided comprehensive insights into the morphological, chemical, and structural properties of the embossed Parylene C. Considering the improved results compared to existing patterning techniques for Parylene C like plasma etching or laser ablation, the developed hot embossing approach yields a superior structural integrity, characterized by increased feature resolution and enhanced sidewall smoothness. These advancements render the method particularly suitable for diverse applications, including but not limited to, sensor optical components, adhesive interfaces for medical wearables, and microfluidic systems.
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  • 文章类型: Journal Article
    二维(2D)材料中的组装和图案化工程对于包含多功能检测器的芯片级设计非常重要。目前,2D材料的图案化和堆叠方法不可避免地引入杂质不稳定性和功能限制。这里,采用空间限制的化学气相沉积方法来实现自组装WS2的最先进的kirigami结构,其特征在于各种层组合和堆叠配置。以这项技术为基础,WS2纳米kirigami与超表面设计集成,在红外光谱中实现具有双向偏振敏感检测能力的光电探测器。纳米kirigami可以消除2D材料设备加工中的一些不可控因素,为跨多个模块的芯片级多功能检测提供自由设计的平台。
    The assembly and patterning engineering in two-dimensional (2D) materials hold importance for chip-level designs incorporating multifunctional detectors. At present, the patterning and stacking methods of 2D materials inevitably introduce impurity instability and functional limitations. Here, the space-confined chemical vapor deposition method is employed to achieve state-of-the-art kirigami structures of self-assembled WS2, featuring various layer combinations and stacking configurations. With this technique as a foundation, the WS2 nano-kirigami is integrated with metasurface design, achieving a photodetector with bidirectional polarization-sensitive detection capability in the infrared spectrum. Nano-kirigami can eliminate some of the uncontrollable factors in the processing of 2D material devices, providing a freely designed platform for chip-level multifunctional detection across multiple modules.
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  • 文章类型: Journal Article
    分支形态发生是许多重要器官的特征,比如肺和肾,和大多数腺体,并且是两种组织行为的净结果:分支点起始和伸长。每个分支器官都有针对其生理功能而定制的独特结构,但是在这些分支管状结构中如何形成图案是发展的一个基本问题。这里,我们使用定量3D形态计量学,延时成像,操纵离体培养的小鼠胚胎器官和缺乏平面细胞极性成分Vangl2的小鼠,以解决发育中的乳腺中的这个问题。我们的结果表明,由于灵活使用了两种不同的分支点起始模式:侧向分支和尖端分叉,胚胎上皮树的拓扑结构高度复杂。这种非刻板印象与显著恒定的平均分支频率形成对比,表明导管生长不变,然而随机的,分支倾向。分支的可能性是有延展性的,并且可以通过操纵Fgf10和Tgfβ1途径来调节。最后,我们的体内数据和离体延时成像提示乳腺分支延长过程中涉及组织重排.
    Branching morphogenesis is a characteristic feature of many essential organs, such as the lung and kidney, and most glands, and is the net result of two tissue behaviors: branch point initiation and elongation. Each branched organ has a distinct architecture customized to its physiological function, but how patterning occurs in these ramified tubular structures is a fundamental problem of development. Here, we use quantitative 3D morphometrics, time-lapse imaging, manipulation of ex vivo cultured mouse embryonic organs and mice deficient in the planar cell polarity component Vangl2 to address this question in the developing mammary gland. Our results show that the embryonic epithelial trees are highly complex in topology owing to the flexible use of two distinct modes of branch point initiation: lateral branching and tip bifurcation. This non-stereotypy was contrasted by the remarkably constant average branch frequency, indicating a ductal growth invariant, yet stochastic, propensity to branch. The probability of branching was malleable and could be tuned by manipulating the Fgf10 and Tgfβ1 pathways. Finally, our in vivo data and ex vivo time-lapse imaging suggest the involvement of tissue rearrangements in mammary branch elongation.
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  • 文章类型: Journal Article
    许多sal可以完全再生出功能完整的肢体。肢体再生是一个精心协调的过程,涉及几个定义的阶段。再生过程中的一个关键事件是胚芽的图案化,以告知细胞必须分化为什么。尽管已知许多参与肢体初始发育的基因在再生过程中被重复使用,这个过程中涉及的确切分子电路还没有完全理解。轴突肢体再生的一些大规模转录谱分析研究已经确定了许多在截肢后上调的转录因子。Sall4是一种转录因子,已被鉴定为在发育过程中维持细胞处于未分化状态中起重要作用,并且在肢体发育中也起着独特的作用。在肢体芽发育过程中Sall4的失活导致肢体的前后图案缺陷。已发现Sall4在非洲爪狼和sal的肢体再生过程中上调,但到目前为止,它的功能尚未测试。我们使用qRT-PCR证实了Sall4在axolotl中的肢体再生过程中上调,并鉴定了它存在于皮肤细胞中,也存在于胚层内的细胞中。使用CRISPR技术,我们将与cas9蛋白复合的Sall4特异性gRNA微注射到胚芽中,以仅在胚芽细胞中特异性敲除Sall4。这导致了肢体再生缺陷,包括缺失的数字,数字元素的融合,桡骨和尺骨的缺陷.这表明在再生过程中,Sall4可能在调节前近端骨骼元素的规格方面发挥类似的作用。
    Many salamanders can completely regenerate a fully functional limb. Limb regeneration is a carefully coordinated process involving several defined stages. One key event during the regeneration process is the patterning of the blastema to inform cells of what they must differentiate into. Although it is known that many genes involved in the initial development of the limb are re-used during regeneration, the exact molecular circuitry involved in this process is not fully understood. Several large-scale transcriptional profiling studies of axolotl limb regeneration have identified many transcription factors that are up-regulated after limb amputation. Sall4 is a transcription factor that has been identified to play essential roles in maintaining cells in an undifferentiated state during development and also plays a unique role in limb development. Inactivation of Sall4 during limb bud development results in defects in anterior-posterior patterning of the limb. Sall4 has been found to be up-regulated during limb regeneration in both Xenopus and salamanders, but to date it function has been untested. We confirmed that Sall4 is up-regulated during limb regeneration in the axolotl using qRT-PCR and identified that it is present in the skin cells and also in cells within the blastema. Using CRISPR technology we microinjected gRNAs specific for Sall4 complexed with cas9 protein into the blastema to specifically knockout Sall4 in blastema cells only. This resulted in limb regenerate defects, including missing digits, fusion of digit elements, and defects in the radius and ulna. This suggests that during regeneration Sall4 may play a similar role in regulating the specification of anterior-proximal skeletal elements.
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  • 文章类型: Journal Article
    花序结构在植物谱系中高度可变,但对于促进繁殖成功至关重要。菊科的头状花序被标记为关键的形态创新,先于该科的多样化和扩展。尽管它具有进化意义,我们对capitulum发展和进化的理解是有限的。这篇评论通过其分子和发育基础的镜头强调了我们目前对capitulum进化的看法。我们试图通过关注两个关键特征来总结我们对小花的理解:图案(小花在小花上的排列)和小花身份规范。请注意,这两个特征是相互连接的,因此小花的身份取决于它们沿花序轴的位置。植物激素,例如生长素,似乎通过未知的机制决定了模式进展和小花身份规范。头部的小花形态受调节小花身份规范的花对称基因的差异表达控制。我们简要总结了ABCE四重奏花卉发育模型在调节菊科小花器官身份中的适用性。总的来说,我们对capitula的理解有了可喜的进步;然而,全面的功能遗传分析是必要的,以充分剖析涉及头毛虫发育的分子途径和机制。
    Inflorescence architecture is highly variable across plant lineages yet is critical for facilitating reproductive success. The capitulum-type inflorescence of the Asteraceae is marked as a key morphological innovation that preceded the family\'s diversification and expansion. Despite its evolutionary significance, our understanding of capitulum development and evolution is limited. This review highlights our current perspective on capitulum evolution through the lens of both its molecular and developmental underpinnings. We attempt to summarize our understanding of the capitulum by focusing on two key characteristics: patterning (arrangement of florets on a capitulum) and floret identity specification. Note that these two features are interconnected such that the identity of florets depends on their position along the inflorescence axis. Phytohormones such as auxin seemingly determine both pattern progression and floret identity specification through unknown mechanisms. Floret morphology in a head is controlled by differential expression of floral symmetry genes regulating floret identity specification. We briefly summarize the applicability of the ABCE quartet model of flower development in regulating the floret organ identity of a capitulum in Asteraceae. Overall, there have been promising advancements in our understanding of capitula; however, comprehensive functional genetic analyses are necessary to fully dissect the molecular pathways and mechanisms involved in capitulum development.
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  • 文章类型: Journal Article
    多能干细胞系之间的遗传差异导致细胞外信号通路的可变活性,定向分化方案的限制性可重复性。在这里,我们使用人胚胎干细胞(hESCs)来询问外源因子如何调节前肠内胚层谱系规范过程中的内源性信号事件。我们发现转化生长因子β1(TGF-β1)激活了推定的人类OTX2/LHX1基因调控网络,该网络通过拮抗内源性Wnt信号来促进前命运。与豪猪抑制相反,TGF-β1的作用不能被外源性Wnt配体逆转,提示SHISA蛋白的诱导和Fzd受体的细胞内积累使TGF-β1处理的细胞对Wnt信号传导难以反应。随后,TGF-β1介导的BMP和Wnt信号抑制抑制肝脏命运并促进胰腺命运。此外,TGF-β1治疗和胰腺特化期间的Wnt抑制联合可重复且稳健地增强hESC细胞系中胰岛素+细胞产量。广泛使用的分化方案的这种修改将提高用于基于细胞的治疗应用的胰腺β细胞产量。
    Genetic differences between pluripotent stem cell lines cause variable activity of extracellular signaling pathways, limiting reproducibility of directed differentiation protocols. Here we used human embryonic stem cells (hESCs) to interrogate how exogenous factors modulate endogenous signaling events during specification of foregut endoderm lineages. We find that transforming growth factor β1 (TGF-β1) activates a putative human OTX2/LHX1 gene regulatory network which promotes anterior fate by antagonizing endogenous Wnt signaling. In contrast to Porcupine inhibition, TGF-β1 effects cannot be reversed by exogenous Wnt ligands, suggesting that induction of SHISA proteins and intracellular accumulation of Fzd receptors render TGF-β1-treated cells refractory to Wnt signaling. Subsequently, TGF-β1-mediated inhibition of BMP and Wnt signaling suppresses liver fate and promotes pancreas fate. Furthermore, combined TGF-β1 treatment and Wnt inhibition during pancreatic specification reproducibly and robustly enhance INSULIN+ cell yield across hESC lines. This modification of widely used differentiation protocols will enhance pancreatic β cell yield for cell-based therapeutic applications.
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  • 文章类型: Journal Article
    本文提出了一种可扩展且直接的技术,用于通过多相3D打印对液态金属/聚合物复合材料进行即时图案化。利用聚合物将液态金属(LM)限制在不同模式中的能力。液态金属的独特流体性质与其在氧化环境内的自钝化氧化物层之间的相互作用确保了与聚合物基质的弹性界面。这项研究介绍了一种创造性的方法,用于实现共晶镓铟(EGaIn)的通用图案,镓合金。图案形成的功效取决于喷嘴的设计和内部几何形状,控制多相相互作用。喷嘴通道内的EGaIn和聚合物之间的相互作用,由横向速度和材料流动压力等变量调节,导致周期性模式。这些模式,当封装在介电聚合物聚乙烯醇(PVA)内时,在电容器组件中表现出增强的固有电容。这一发现不仅揭示了具有成本效益和高灵敏度的电容式压力传感器的潜力,而且还强调了这些新颖模式在精确运动检测中的潜在应用。包括心率监测,和步态概况的综合分析。先进材料和复杂图案技术的融合在可穿戴传感和全面的人体运动分析领域提出了变革性的前景。
    This paper presents a scalable and straightforward technique for the immediate patterning of liquid metal/polymer composites via multiphase 3D printing. Capitalizing on the polymer\'s capacity to confine liquid metal (LM) into diverse patterns. The interplay between distinctive fluidic properties of liquid metal and its self-passivating oxide layer within an oxidative environment ensures a resilient interface with the polymer matrix. This study introduces an inventive approach for achieving versatile patterns in eutectic gallium indium (EGaIn), a gallium alloy. The efficacy of pattern formation hinges on nozzle\'s design and internal geometry, which govern multiphase interaction. The interplay between EGaIn and polymer within the nozzle channels, regulated by variables such as traverse speed and material flow pressure, leads to periodic patterns. These patterns, when encapsulated within a dielectric polymer polyvinyl alcohol (PVA), exhibit an augmented inherent capacitance in capacitor assemblies. This discovery not only unveils the potential for cost-effective and highly sensitive capacitive pressure sensors but also underscores prospective applications of these novel patterns in precise motion detection, including heart rate monitoring, and comprehensive analysis of gait profiles. The amalgamation of advanced materials and intricate patterning techniques presents a transformative prospect in the domains of wearable sensing and comprehensive human motion analysis.
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  • 文章类型: Journal Article
    3D(生物)打印技术推动了生物医学领域的发展。然而,组织工程处于起步阶段,体外组织形成的(生物)打印仿生结构仍然是默认的。作为一种改进体外研究的新方法,我们建议在3D打印过程中使用可交联的水性支撑浴来图案化支架的特征。使用流体相,可以将不同的分子添加到促进细胞行为指导和区室化的底物的特定位置。此外,机械方面可以通过改变获取(生物)打印的溶液的类型或浓度来定制。在这项研究中,我们首先评估了不同配方的藻酸盐/明胶,以改善我们的印刷中的细胞定植。在明胶含量较低的配方上,U2OS细胞增长2.83倍。此外,藻酸盐-明胶水凝胶在空气和液相中均具有良好的可印刷性,然而,液相印刷显示出更好的印刷保真度,因为它减少了水凝胶链的塌陷和扩散。接下来,在我们的印刷物中,采用液相方法指导细胞定植.首先,在印刷过程中通过将水凝胶与不同浓度的CaCl2交联而产生不同的刚度。因此,U2OS细胞被分隔在印刷的较硬部分上。此外,使用液相将RGD分子添加到水凝胶的特定部分也促进了对细胞生长的指导。最后,我们的结果表明,通过将更硬的藻酸盐-明胶水凝胶与增加浓度的RGD相结合,我们可以产生协同作用,并将细胞生长提高3.17倍。这项工作提出了一种新的打印工艺,用于通过使用流体相来生成更忠实的体内环境复制来定制水凝胶基底中的多个参数。 .
    Three-dimensional (3D) (bio)printing technology has boosted the advancement of the biomedical field. However, tissue engineering is an evolving field and (bio)printing biomimetic constructions for tissue formation is still a challenge. As a new methodology to facilitate the construction of more complex structures, we suggest the use of the fluid-phase 3D printing to pattern the scaffold\'s properties. The methodology consists of an exchangeable fluid-phase printing medium in which the constructions are fabricated and patterned during the printing process. Using the fluid-phase methodology, the biological and mechanical properties can be tailored promoting cell behaviour guidance and compartmentalization. In this study, we first assessed different formulations of alginate/gelatin to create a stable substrate capable to promote massive cell colonizationin vitroover time. Overall, formulations with lower gelatin content and 2-(N-morpholino)ethanesulfonic acid (MES) buffer as a solvent showed better stability under cell culture conditions and enhanced U2OS cell growth. Next, the fluid-phase showed better printing fidelity and resolution in comparison to air printing as it diminished the collapsing and the spread of the hydrogel strand. In sequence, the fluid-phase methodology was used to create functionalized alginate-gelatin-arginylglycylaspartic acid peptide (RGD) hydrogels via carbodiimides chemistry. The alginate-gelatin-RGD hydrogels showed an increase of 2.97-fold in cell growth and more spread substrate colonization in comparison to alginate-gelatin hydrogel. Moreover, the fluid-phase methodology was used to add RGD molecules to pre-determined parts of the alginate-gelatin substrate during the printing process promoting U2OS cell compartmentalization. In addition, different substrate stiffnesses were also created via fluid-phase by crosslinking the hydrogel with different concentrations of CaCl2during the printing process. As a result, the U2OS cells were also compartmentalized on the stiffer parts of the printings. Finally, our results showed that by combining stiffer hydrogel with RGD increasing concentrations we can create a synergetic effect and boost cell metabolism by up to 3.17-fold. This work presents an idea of a new printing process for tailoring multiple parameters in hydrogel substrates by using fluid-phase to generate more faithful replication of thein vivoenvironment.
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  • 文章类型: Journal Article
    理解心理学是现代社会的一项重要任务,它有助于预测人类行为并提供相应的反馈。监测微弱的心理和情绪变化需要生物电子设备是可伸展的和兼容的,以进行不显眼和高保真的信号采集。导电聚合物薄膜被认为是理想的界面;然而,同时平衡机械鲁棒性和光电性能是非常具有挑战性的。这里,我们报道了一种基于石墨烯层介导的光刻双网导电聚合物的40nm厚的薄膜,同时实现可拉伸性,导电性和顺应性。光刻聚合物和石墨烯赋予薄膜光图案化能力,增强应力耗散能力,以及通过π-π分子重排提高光电电导率(4458Scm-1@>90%透明度),静电相互作用和氢键。我们进一步将薄膜涂在波纹面部皮肤上,监测细微的肌电图,并执行机器学习算法来理解复杂的情绪,表明可拉伸和柔顺的生物电子学的杰出能力。本文受版权保护。保留所有权利。
    Understanding psychology is an important task in modern society which helps predict human behavior and provide feedback accordingly. Monitoring of weak psychological and emotional changes requires bioelectronic devices to be stretchable and compliant for unobtrusive and high-fidelity signal acquisition. Thin conductive polymer film is regarded as an ideal interface; however, it is very challenging to simultaneously balance mechanical robustness and opto-electrical property. Here, a 40 nm-thick film based on photolithographic double-network conductive polymer mediated by graphene layer is reported, which concurrently enables stretchability, conductivity, and conformability. Photolithographic polymer and graphene endow the film photopatternability, enhance stress dissipation capability, as well as improve opto-electrical conductivity (4458 S cm-1@>90% transparency) through molecular rearrangement by π-π interaction, electrostatic interaction, and hydrogen bonding. The film is further applied onto corrugated facial skin, the subtle electromyogram is monitored, and machine learning algorithm is performed to understand complex emotions, indicating the outstanding ability for stretchable and compliant bioelectronics.
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