Engineering

Engineering
  • 文章类型: Journal Article
    管道污染物检测在各个行业中占有相当重要的地位,比如航空,海事,医学,和其他相关领域。此功能有利于预测设备潜在故障,确定操作情况,及时维护,和寿命预测。然而,现有的大多数方法都是离线操作的,在线可检测参数相对单一。这种限制阻碍了实时现场检测和设备状态的全面评估。为了应对这些挑战,本文提出了一种传感方法,该方法集成了超声波单元和电磁感应单元,用于实时检测管道内的各种污染物和流量。超声单元包括通过微加工技术制造的柔性换能器贴片,这不仅可以使安装更容易,而且可以聚焦声场。此外,传感单元包括三个对称的电磁线圈。通过对超声波和感应信号的综合分析,所提出的方法可用于有效区分磁性金属颗粒(例如,铁),非磁性金属颗粒(例如,铜),非金属颗粒(例如,陶瓷),和气泡。这种包容性分类涵盖了管道中可能存在的几乎所有类型的污染物。此外,流体速度可以通过超声多普勒频移来确定。所提出的检测原理的有效性已通过数学模型和有限元仿真验证。在14毫米直径的管道内系统地测试了具有不同速度的各种污染物。实验结果表明,该传感器能够有效检测0.5-3mm范围内的污染物,准确区分污染物类型,并测量流速。
    Pipe contaminant detection holds considerable importance within various industries, such as the aviation, maritime, medicine, and other pertinent fields. This capability is beneficial for forecasting equipment potential failures, ascertaining operational situations, timely maintenance, and lifespan prediction. However, the majority of existing methods operate offline, and the detectable parameters online are relatively singular. This constraint hampers real-time on-site detection and comprehensive assessments of equipment status. To address these challenges, this paper proposes a sensing method that integrates an ultrasonic unit and an electromagnetic inductive unit for the real-time detection of diverse contaminants and flow rates within a pipeline. The ultrasonic unit comprises a flexible transducer patch fabricated through micromachining technology, which can not only make installation easier but also focus the sound field. Moreover, the sensing unit incorporates three symmetrical solenoid coils. Through a comprehensive analysis of ultrasonic and induction signals, the proposed method can be used to effectively discriminate magnetic metal particles (e.g., iron), nonmagnetic metal particles (e.g., copper), nonmetallic particles (e.g., ceramics), and bubbles. This inclusive categorization encompasses nearly all types of contaminants that may be present in a pipeline. Furthermore, the fluid velocity can be determined through the ultrasonic Doppler frequency shift. The efficacy of the proposed detection principle has been validated by mathematical models and finite element simulations. Various contaminants with diverse velocities were systematically tested within a 14 mm diameter pipe. The experimental results demonstrate that the proposed sensor can effectively detect contaminants within the 0.5-3 mm range, accurately distinguish contaminant types, and measure flow velocity.
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  • 文章类型: Journal Article
    熟练的连续动作需要感觉运动控制的微妙平衡,包括鲁棒性和适应性。然而,由于广泛的感觉运动经历,由感觉扰动触发的运动和神经反应是否都经历了可塑性适应,目前尚不清楚。通过比较钢琴家和非音乐家,我们评估了暂时延迟的音调产生对钢琴演奏过程中随后的运动动作和事件相关电位(ERP)的影响。在扰动之后,非音乐家但钢琴家的击键间隔异常延长。相比之下,扰动后的击键速度仅在钢琴家中增加。回归模型表明,击键间隔的变化与ERP的变化有关,特别是在额叶和顶叶区域。击键速度的改变与时间区域的P300分量相关。这些发现表明,不同的神经机制是不同熟练程度的健壮和自适应感觉运动技能的基础。
    Skillful sequential action requires the delicate balance of sensorimotor control, encompassing both robustness and adaptability. However, it remains unknown whether both motor and neural responses triggered by sensory perturbation undergo plastic adaptation as a consequence of extensive sensorimotor experience. We assessed the effects of transiently delayed tone production on the subsequent motor actions and event-related potentials (ERPs) during piano performance by comparing pianists and non-musicians. Following the perturbation, the inter-keystroke interval was abnormally prolonged in non-musicians but not in pianists. By contrast, the keystroke velocity following the perturbation was increased only in the pianists. A regression model demonstrated that the change in the inter-keystroke interval covaried with the ERPs, particularly at the frontal and parietal regions. The alteration in the keystroke velocity was associated with the P300 component of the temporal region. These findings suggest that different neural mechanisms underlie robust and adaptive sensorimotor skills across proficiency level.
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  • 文章类型: Journal Article
    这项研究旨在制备和评估基于新型生物材料的活性微针(MN)贴片及其有效的耦合(物理和电)透皮递送模型药物(Linezoid)。改良的MN面片(例如,由Linezoid制成,硼酸化壳聚糖,聚乙烯醇和D-山梨糖醇)是使用真空微模塑法进行工程改造的。物理化学,FTIR(傅里叶变换红外),在硅,对制备的配方进行结构和热分析,以确定MN质量,组成和完整性。体外力学试验,膜毒性,药物释放,抗生物膜,离体粘膜粘附,进行了插入和体内抗生物膜研究,以进一步验证偶联系统的可行性。优化的MN贴剂配方(CSHP3-包含3%w/v硼酸化壳聚糖,3.5%w/vPVA和10%w/wD-山梨糖醇)显示尖头,具有符合物理化学特征的等距离和均匀表面的微米尺度投影。FTIR分析证实了改性(即,硼化)壳聚糖与CSHP3成分之间的相容性以及相互作用。硅分析显示所有制剂成分之间的非共价相互作用。此外,与利奈唑胺-粘蛋白对应物相比,硼化的壳聚糖-粘蛋白糖蛋白复合物显示出更强的结合(〜1.86倍更高的CScore)。热分析表明CSHP3的无定形性质。与对照相比,CSHP3显示的拉伸强度高出1.42倍(即,纯壳聚糖,聚乙烯醇和基于D-山梨醇的MN贴片)。膜毒性研究表明CSHP3具有无毒和生理相容性。90分钟内,从CSHP3释放91.99±2.3%的利奈唑胺。在琼脂糖凝胶的释放研究过程中,CSHP3-离子电渗疗法治疗导致约1.78和约1.20倍的亚甲蓝覆盖面积和光密度,分别,与单独的CSHP3治疗相比,在60分钟内。用CSHP3处理的金黄色葡萄球菌生物膜显示其质量减少65±4.2%。CSHP3MN贴片保持粘附在兔口腔粘膜上6±0.15小时。用CSHP3和CSHP3-离子电渗疗法组合处理的粘膜显示在上皮层中产生了通路,而对下层固有层没有任何损害。使用CSHP3-离子电渗疗法耦合方法治疗7天后,记录了从口腔粘膜伤口中根除金黄色葡萄球菌并完成了组织再生。
    This study aimed to prepare and assess active microneedle (MN) patches based on a novel biomaterial and their effective coupled (physical and electrical) transdermal delivery of a model drug (Linezoid). Modified MN patches (e.g. fabricated from Linezoid, boronated chitosan, polyvinyl alcohol and D-sorbitol) were engineered using a vacuum micromoulding method. Physicochemical, FTIR (Fourier transform infrared), in-silico, structural and thermal analysis of prepared formulations were conducted to ascertain MN quality, composition and integrity. In-vitro mechanical tests, membrane toxicity, drug release, antibiofilm, ex-vivo mucoadhesion, insertion and in-vivo antibiofilm studies were performed to further validate viability of the coupled system. Optimized MN patch formulation (CSHP3 - comprising of 3 % w/v boronated chitosan, 3.5 % w/v PVA and 10 % w/w D-sorbitol) exhibited sharp-tipped, equi-distant and uniform-surfaced micron-scaled projections with conforming physicochemical features. FTIR analysis confirmed modification (i.e., boronation) of chitosan and compatibility as well as interaction between CSHP3 constituents. In-silico analysis indicated non-covalent interactions between all formulation constituents. Moreover, boronated chitosan-mucin glycoprotein complex showed a stronger bonding (∼1.86 times higher CScore) as compared to linezolid-mucin counterpart. Thermal analysis indicated amorphous nature of CSHP3. A ∼ 1.42 times higher tensile strength was displayed by CSHP3 as compared to control (i.e., pure chitosan, polyvinyl alcohol and D-sorbitol-based MN patch). Membrane toxicity study indicated non-toxic and physiological compatible nature of CSHP3. Within 90 min, 91.99 ± 2.3 % linezolid was released from CSHP3. During release study on agarose gel, CSHP3-iontophoresis treatment resulted in a ∼ 1.78 and ∼ 1.20 times higher methylene blue-covered area and optical density, respectively, within 60 min as compared to CSHP3 treatment alone. Staphylococcus aureus biofilms treated with CSHP3 exhibited 65 ± 4.2 % reduction in their mass. CSHP3 MN patches remained adhered to the rabbit oral mucosa for 6 ± 0.15 h. Mucosa treated with CSHP3 and CSHP3-iontophoresis combination showed a generation of pathways in the epithelium layers without any damage to the underlying lamina propria. Eradication of Staphylococcus aureus from oral mucosal wounds and complete tissue regeneration was recorded following 7-day treatment using CSHP3-iontophoresis coupled approach.
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  • 文章类型: Journal Article
    细胞信号传导过程或离子转运是由位于细胞表面的膜蛋白(MPs)介导的,MPs的功能研究主要使用内源性或瞬时表达靶蛋白的细胞进行。纯化的MPs在活细胞表面的重建将具有操作时间短和靶向基因转染困难的细胞的能力的优点。然而,MPs在活细胞中的直接重建尚未建立。传统的去污剂介导的将MPs重建成脂双层的方法不能应用于活细胞,因为这会破坏和改革脂质双层结构,这对细胞活力是有害的。在这项研究中,我们证明了GPCRs(前列腺素E2受体4[EP4]和胰高血糖素样肽-1受体[GLP1R])或5-羟色胺受体3A(5HT3A),配体门控离子通道,用两亲性聚γ-谷氨酸(APG)稳定,可以在不影响细胞活力的情况下重建到哺乳动物细胞质膜中。此外,在哺乳动物细胞中重建的5HT3A显示出配体依赖性的Ca2+离子转运活性。APG介导的GPCR在合成脂质体中的重建表明,APG与膜表面电荷之间的静电相互作用有助于重建过程。这种APG介导的膜工程方法可以应用于活细胞中的MPs对细胞膜的功能修饰。
    The cellular signaling process or ion transport is mediated by membrane proteins (MPs) located on the cell surface, and functional studies of MPs have mainly been conducted using cells endogenously or transiently expressing target proteins. Reconstitution of purified MPs in the surface of live cells would have advantages of short manipulation time and ability to target cells in which gene transfection is difficult. However, direct reconstitution of MPs in live cells has not been established. The traditional detergent-mediated reconstitution method of MPs into a lipid bilayer cannot be applied to live cells because this disrupts and reforms the lipid bilayer structure, which is detrimental to cell viability. In this study, we demonstrated that GPCRs (prostaglandin E2 receptor 4 [EP4] and glucagon-like peptide-1 receptor [GLP1R]) or serotonin receptor 3A (5HT3A), a ligand-gated ion channel, stabilized with amphiphilic poly-γ-glutamate (APG), can be reconstituted into mammalian cell plasma membranes without affecting cell viability. Furthermore, 5HT3A reconstituted in mammalian cells showed ligand-dependent Ca2+ ion transport activity. APG-mediated reconstitution of GPCR in synthetic liposomes showed that electrostatic interaction between APG and membrane surface charge contributed to the reconstitution process. This APG-mediated membrane engineering method could be applied to the functional modification of cell membranes with MPs in live cells.
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  • 文章类型: News
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  • 文章类型: Journal Article
    神经形态系统的兴起解决了当前计算架构的缺点,特别是关于能源效率和可扩展性。这些系统使用尖端技术,如Pt/SnOx/TiN忆阻器,它可以有效地模拟突触行为,并为现代计算挑战提供潜在的解决方案。此外,它们的单极电阻切换能力能够精确调制突触权重,促进类似于生物突触的节能并行处理。此外,忆阻器“尖峰率依赖性可塑性增强了神经回路的适应性,在智能计算中提供有前途的应用。将忆阻器集成到边缘计算架构中进一步突出了它们在解决与传统云计算模型相关的安全性和效率问题方面的重要性。
    The rise of neuromorphic systems has addressed the shortcomings of current computing architectures, especially regarding energy efficiency and scalability. These systems use cutting-edge technologies such as Pt/SnOx/TiN memristors, which efficiently mimic synaptic behavior and provide potential solutions to modern computing challenges. Moreover, their unipolar resistive switching ability enables precise modulation of the synaptic weights, facilitating energy-efficient parallel processing that is similar to biological synapses. Additionally, memristors\' spike-rate-dependent plasticity enhances the adaptability of neural circuits, offering promising applications in intelligent computing. Integrating memristors into edge computing architectures further highlights their importance in tackling the security and efficiency issues associated with conventional cloud computing models.
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  • 文章类型: Introductory Journal Article
    本文是对“不断变化的价值和能源系统”主题集合的介绍,其中包括六个贡献,这些贡献检查了有关设计的价值变化实例,能源系统的使用和操作。本引言讨论了在能源转型中考虑价值的必要性。它研究了价值和价值变化的概念,以及如何在能源系统的设计中解决价值。能源和能源系统背景下的价值变化是一个最近获得关注的话题。Current,过去,能量转换通常集中在有限范围的值上,比如可持续性,在留下其他突出价值的同时,比如能源民主,或者能源正义,从图片中。此外,这些价值观在这些系统的设计中根深蒂固:利益相关者很难在这些系统的使用和操作中解决新的关切和价值观,导致进一步昂贵的过渡和系统大修。为了解决这个问题,需要更好地理解能源系统背景下的价值变化。我们还需要考虑对治理的进一步要求,能源系统的机构和工程设计,以适应未来的价值变化。开放,透明度,适应性,灵活性和模块化是当前能源转型中的新要求,需要进一步探索和审查。
    This paper is the introduction to a topical collection on \"Changing Values and Energy Systems\" that consists of six contributions that examine instances of value change regarding the design, use and operation of energy systems. This introduction discusses the need to consider values in the energy transition. It examines conceptions of value and value change and how values can be addressed in the design of energy systems. Value change in the context of energy and energy systems is a topic that has recently gained traction. Current, and past, energy transitions often focus on a limited range of values, such as sustainability, while leaving other salient values, such as energy democracy, or energy justice, out of the picture. Furthermore, these values become entrenched in the design of these systems: it is hard for stakeholders to address new concerns and values in the use and operation of these systems, leading to further costly transitions and systems\' overhaul. To remedy this issue, value change in the context of energy systems needs to be better understood. We also need to think about further requirements for the governance, institutional and engineering design of energy systems to accommodate future value change. Openness, transparency, adaptiveness, flexibility and modularity emerge as new requirements within the current energy transition that need further exploration and scrutiny.
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  • 文章类型: Journal Article
    为了解决低频范围内漏气和谐振频率附近电声换能结构中的异步振动引起的严重声学性能恶化,提出了一种新颖的密封策略,该策略针对最广泛报道的压电MEMS扬声器设计之一。本设计由多个悬臂梁组成,其中悬臂梁之间的气隙通过毛细效应自动和选择性地填充液体聚二甲基硅氧烷(PDMS),其次是固化。在概念验证演示中,在使用IEC耳部模拟器的实验中密封后,低于100Hz的频率范围内的声压级(SPL)显着增加。具体来说,对于40Vpp驱动电压,在20Hz下SPL增加4.9dB。此外,在悬臂梁的谐振频率(18kHz-19kHz)附近,由制造工艺不均匀性引起的异步振动引起的SPL响应也显着改善。成功地将SPL提高到大约17.5dB。此外,密封器件在100Hz至16kHz的频带中具有与初始对应物几乎相同的SPL响应,在40Vpp的驱动电压下,1kHz时的总谐波失真(THD)为0.728%。与现有的密封方法相比,目前的方法提供了简单的操作,低损坏风险,出色的可重复性/可靠性和出色的鲁棒性优势,为MEMS声学器件提供了一种有前途的技术解决方案。
    To address the serious acoustic performance deterioration induced by air leakage in the low-frequency range and the asynchronous vibration in electroacoustic transduction structures near the resonant frequency, a novel sealing strategy is proposed that targets one of the most widely reported piezoelectric MEMS speaker designs. This design consists of multiple cantilever beams, in which the air gaps between cantilevers are automatically and selectively filled with liquid polydimethylsiloxane (PDMS) via the capillary effect, followed by curing. In the proof-of-concept demonstration, the sound pressure level (SPL) within the frequency range lower than 100 Hz markedly increased after sealing in an experiment using an IEC ear simulator. Specifically, the SPL is increased by 4.9 dB at 20 Hz for a 40 Vpp driving voltage. Moreover, the deteriorated SPL response near the resonant frequencies of the cantilever beams (18 kHz-19 kHz) caused by their asynchronous vibration induced by the fabrication process nonuniformity also significantly improved, which successfully increased the SPL to approximately 17.5 dB. Moreover, sealed devices feature nearly the same SPL response as the initial counterpart in the frequency band from 100 Hz to 16 kHz and a total harmonic distortion (THD) of 0.728% at 1 kHz for a 40 Vpp driving voltage. Compared with existing sealing methods, the current approach offers easy operation, low damage risk, excellent repeatability/reliability and excellent robustness advantages and provides a promising technical solution for MEMS acoustic devices.
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  • 文章类型: Journal Article
    女性生殖系统对女性的健康至关重要,人类生殖和社会福祉。然而,传统研究模式的临床转化由于效果不确定和效率低而受到限制。新的证据表明,微流控芯片为研究女性生殖系统提供了有价值的平台,虽然没有一篇论文全面讨论过这个话题。这里,在PubMed中确定了14,669项记录中的161项研究,Scopus,WebofScience,ScienceDirect和IEEEXplore数据库。其中,61项研究集中在卵母细胞上,这进一步涉及文化,细胞手术(卵母细胞分离,旋转,摘除,和剥蚀),评估和冷冻保存。40项研究调查了通过微流控芯片操纵胚胎,覆盖体外受精,冷冻保存和功能评估。46项研究重建了体内器官的生理和病理状态,主要涉及胎盘和胎膜研究。14项研究进行药物筛选和毒性测试。在这次审查中,我们总结了目前微流控芯片在女性生殖系统研究中的应用,材料和方法的进步,讨论未来的挑战。目前的证据表明,微流控芯片辅助生殖系统重建是有希望的,迫切需要更多的研究。
    The female reproductive system is essential to women\'s health, human reproduction and societal well-being. However, the clinical translation of traditional research models is restricted due to the uncertain effects and low efficiency. Emerging evidence shows that microfluidic chips provide valuable platforms for studying the female reproductive system, while no paper has ever comprehensively discussed the topic. Here, a total of 161 studies out of 14,669 records are identified in PubMed, Scopus, Web of Science, ScienceDirect and IEEE Xplore databases. Among these, 61 studies focus on oocytes, which further involves culture, cell surgeries (oocyte separation, rotation, enucleation, and denudation), evaluation and cryopreservation. Forty studies investigate embryo manipulation via microfluidic chips, covering in vitro fertilization, cryopreservation and functional evaluation. Forty-six studies reconstitute both the physiological and pathological statuses of in vivo organs, mostly involved in placenta and fetal membrane research. Fourteen studies perform drug screening and toxicity testing. In this review, we summarize the current application of microfluidic chips in studying the female reproductive system, the advancements in materials and methods, and discuss the future challenges. The present evidence suggests that microfluidic chips-assisted reproductive system reconstruction is promising and more studies are urgently needed.
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  • 文章类型: Journal Article
    准确的地理交通预测在城市交通规划中起着至关重要的作用,交通管理,和地理空间人工智能(GeoAI)。尽管深度学习模型在地理交通预测方面取得了重大进展,它们在有效捕获长期时间依赖性和建模异构动态空间依赖性方面仍然面临挑战。为了解决这些问题,我们提出了一种新颖的基于深度变压器的异构时空图学习模型,用于地理交通预测。我们的模型包含一个时间转换器,可以捕获交通数据中的长期时间模式,而无需简单的数据融合。此外,我们在不同的图层中引入了自适应归一化图结构,使模型能够捕获动态空间依赖关系并适应不同的交通场景,特别是对于异质关系。我们对四个主要的公共数据集进行了全面的实验和可视化,并证明与现有方法相比,我们的模型实现了最先进的结果。
    Accurate geographical traffic forecasting plays a critical role in urban transportation planning, traffic management, and geospatial artificial intelligence (GeoAI). Although deep learning models have made significant progress in geographical traffic forecasting, they still face challenges in effectively capturing long-term temporal dependencies and modeling heterogeneous dynamic spatial dependencies. To address these issues, we propose a novel deep transformer-based heterogeneous spatiotemporal graph learning model for geographical traffic forecasting. Our model incorporates a temporal transformer that captures long-term temporal patterns in traffic data without simple data fusion. Furthermore, we introduce adaptive normalized graph structures within different graph layers, enabling the model to capture dynamic spatial dependencies and adapt to diverse traffic scenarios, especially for the heterogeneous relationship. We conduct comprehensive experiments and visualization on four primary public datasets and demonstrate that our model achieves state-of-the-art results in comparison to existing methods.
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