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Measurement of Water Diffusion Coefficient in Cross-Linked Gelatins Using the Terahertz Time-Domain Spectroscopy Technique

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Measurement of Water Diffusion Coefficient in Cross-Linked G...

Conference on Lasers and Electro-Optics (CLEO)

作者： D. Walden D. Chakraborty J. Cheng A. Straksys A. Stirke W. CMA Melo A. Jukna I. Komissarov Roman Sobolewski Department of Physics and Astronomy University of Rochester Rochester New York USA Laboratory for Laser Energetics University of Rochester Rochester New York USA Materials Science Graduate Program University of Rochester Rochester New York USA State Research Institute Center for Physical Sciences & Technology Vilnius Lithuania Department of Physics Vilnius Gediminas Technical University Vilnius Lithuania Department of Electrical and Computer Engineering University of Rochester Rochester New York USA

A novel method has been developed to evaluate the water diffusion dynamics in gelatin-based gels, based on transient terahertz time-domain spectroscopy measurements. Such gels are widely used models for human skin.

ISBN: (纸本)9798350369311

关键词： Spectroscopy Measurement by laser beam Lasers and electrooptics Laser modes Skin Time-domain analysis Transient analysis Electro-optical waveguides

Structural engineering of graphene for high-resolution cryo-electron microscopy

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SmartMat 2021年第2期2卷 202-212页

作者： Jie Xu Xiaoya Cui Nan Liu Yanan Chen Hong-Wei Wang Ministry of Education Key Laboratory of Protein Sciences Beijing Advanced Innovation Center for Structural BiologySchool of Life SciencesTsinghua UniversityBeijingChina Tsinghua-Peking Joint Center for Life Sciences Tsinghua UniversityBeijingChina School of Materials Science and Engineering Tianjin UniversityTianjinChina Joint Graduate Program of Peking-Tsinghua-NIBS School of Life SciencesTsinghua UniversityBeijingChina Beijing Frontier Research Center for Biological Structures Tsinghua UniversityBeijingChina

The revolutionary improvement of hardware and algorithm in cryogenic electron microscopy(cryo-EM)has made it a routine method to obtain structures of macromolecules at near-atomic ***,this technique still faces many *** structure-solving efficiency of cryo-EM can be significantly reduced by the biomolecules'denaturation on the air–water interfaces,the preferred orientation,strong background noise from supporting films and particle motion,and so *** overcome these problems,nanomaterials with ultrahigh electronic conductivity and ultrathin thickness are explored as promising cryo-EM specimen supporting ***,we summarize the structural engineering of graphene,for example,surface and interface modification,as supporting films for grids and the application on high-resolution cryo-EM and discuss potential future perspectives.

关键词： graphene high-resolution cryogenic electron microscopy life science liquid cell tomography

Computational modeling of the physical features that influence breast cancer invasion into adipose tissue

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arXiv 2024年

作者： Zheng, Yitong Wang, Dong Beeghly, Garrett Fischbach, Claudia Shattuck, Mark D. O’Hern, Corey S. Department of Mechanical Engineering & Materials Science Yale University New HavenCT06520 United States Integrated Graduate Program in Physical and Engineering Biology Yale University New HavenCT06520 United States Nancy E. and Peter C. Meinig School of Biomedical Engineering Cornell University IthacaNY14853 United States Benjamin Levich Institute Physics Department City College of New York New YorkNY10031 United States Department of Physics Yale University New HavenCT06520 United States

Breast cancer invasion into adipose tissue strongly influences disease progression and metastasis. The degree of cancer cell invasion into adipose tissue depends on numerous biochemical and physical properties of cancer cells, adipocytes, and other key components of adipose tissue. We model breast cancer invasion into adipose tissue as a physical process by carrying out simulations of active, cohesive spherical particles (cancer cells) invading into confluent packings of deformable polyhedra (adipocytes). We quantify the degree of invasion by calculating the interfacial area At between cancer cells and adipocytes. We determine the long-time value of At versus the activity and strength of the cohesion between cancer cells, as well as mechanical properties of the adipocytes and extracellular matrix (ECM) in which the adipocytes are embedded. We show that the degree of invasion collapses onto a master curve by plotting it versus a dimensionless energy scale Ec, which grows linearly with mean-square fluctuations and persistence time of the cancer cell velocities, is inversely proportional to the pressure of the system, and has an offset that increases with the cancer cell cohesive energy. The condition, Ec 1, indicates that cancer cells will invade the adipose tissue, whereas for Ec 1, the cancer cells and adipocytes remain demixed. We also show that constraints on adipocyte positions by the ECM decrease At relative to that obtained for unconstrained adipocytes. Finally, spatial heterogeneity in structural and mechanical properties of the adipocytes in the presence of ECM impedes invasion relative to adipose tissue with uniform properties. © 2024, CC BY-NC-ND.

关键词： Cancer cells

Terahertz spin dynamics in rare-earth orthoferrites

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Photonics Insights 2022年第2期1卷 1-56页

作者： Xinwei Li Dasom Kim Yincheng Liu Junichiro Kono Department of Physics California Institute of TechnologyPasadenaUSA Department of Electrical and Computer Engineering Rice UniversityHoustonUSA Applied Physics Graduate Program Smalley-Curl InstituteRice UniversityHoustonUSA Department of Physics and Astronomy Rice UniversityHoustonUSA Department of Materials Science and NanoEngineering Rice UniversityHoustonUSA

Recent interest in developing fast spintronic devices and laser-controllable magnetic solids has sparked tremendous experimental and theoretical efforts to understand and manipulate ultrafast dynamics in *** of spin dynamics in the terahertz(THz)frequency range are particularly important for elucidating microscopic pathways toward novel device ***,we review THz phenomena related to spin dynamics in rare-earth orthoferrites,a class of materials promising for antiferromagnetic *** expand this topic into a description of four key elements.(1)We start by describing THz spectroscopy of spin excitations for probing magnetic phase transitions in thermal *** acoustic magnons are useful indicators of spin reorientation transitions,electromagnons that arise from dynamic magnetoelectric couplings serve as a signature of inversion-symmetry-breaking phases at low temperatures.(2)We then review the strong laser driving scenario,where the system is excited far from equilibrium and thereby subject to modifications to the free-energy *** pathways for ultrafast laser manipulation of magnetic order are discussed.(3)Furthermore,we review a variety of protocols to manipulate coherent THz magnons in time and space,which are useful capabilities for antiferromagnetic spintronic applications.(4)Finally,new insights into the connection between dynamic magnetic coupling in condensed matter and the Dicke superradiant phase transition in quantum optics are *** presenting a review on an array of THz spin phenomena occurring in a single class of materials,we hope to trigger interdisciplinary efforts that actively seek connections between subfields of spintronics,which will facilitate the invention of new protocols of active spin control and quantum phase engineering.

关键词： terahertz spin dynamics magnetism orthoferrite ultrafast spectroscopy magneto-optics

Novel drying additives and their evaluation for self-flowing refractory castables

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arXiv 2021年

作者： Bezerra, B.P. Luz, A.P. Pandolfelli, V.C. Federal University of Sao Carlos Graduate Program in Materials Science and Engineering Rod. Washington Luis km 235 São Carlos - SPCEP:13565-905 Brazil

The drying step of dense refractory castables containing hydraulic binders is a critical process, which usually requires using slow heating rates due to the high explosion trend of such materials during their first thermal treatment. Thus, this work investigated the performance of alternative additives to induce faster and safer drying of self-flowing high-alumina refractory castables bonded with calcium aluminate cement (CAC) or hydratable alumina (HA). The following materials were analyzed for this purpose: polymeric fibers, a permeability enhancing compound (RefPac MIPORE 20) and an organic additive (aluminum salt of 2-hydroxypropanoic acid). The drying behavior and explosion resistance of the cured samples were evaluated when subjecting the prepared castables to heating rates of 2, 5 or 20°C/min and the obtained data were then correlated to the potential of the drying agents to improve the permeability and mechanical strength level of the refractories at different temperatures. The collected results attested that the selected additives were more efficient in optimizing the drying behavior of the CAC-bonded compositions, whereas the HA-containing castables performed better when the aluminum-based salt was blended with a small amount of CAC (0.5 wt.%), which changed the binders hydration reaction sequence and optimized the permeability level of the resulting microstructure. Consequently, some of the designed compositions evaluated in this work showed improved drying behavior and no explosion was observed even during the tests carried out under a high heating rate (20°C/min). © 2021, CC BY-NC-ND.

关键词： Aluminum oxide

Exploring the magnetic properties of individual barcode nanowires using wide-field diamond microscopy

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arXiv 2023年

作者： Yoon, Jungbae Moon, Jun Hwan Jeong, Jugyeong Kim, Yu Jin Kim, Kihwan Kang, Hee Seong Jeon, Yoo Sang Oh, Eunsoo Lee, Sun Hwa Han, Kihoon Lee, Dongmin Lee, Chul-Ho Kim, Young Keun Lee, Donghun Department of Physics Korea University Seoul Korea Republic of Department of Materials Science and Engineering Korea University Seoul Korea Republic of Institute for High Technology Materials and Devices Korea University Seoul Korea Republic of KU-KIST Graduate School of Converging Science and Technology Korea University Seoul Korea Republic of Center for Hydrogen∙Fuel Cell Research Korea Institute of Science and Technology Seoul Korea Republic of Ulsan44919 Korea Republic of BK21 Graduate Program Department of Biomedical Sciences Korea University College of Medicine Seoul Korea Republic of Department of Neuroscience Korea University College of Medicine Seoul Korea Republic of Department of Anatomy Korea University College of Medicine Seoul Korea Republic of

Barcode magnetic nanowires typically comprise a multilayer magnetic structure in a single body with more than one segment type. Interestingly, owing to selective functionalization and novel interactions between the layers, barcode magnetic nanowires have attracted significant attention, particularly in the field of bioengineering. However, an analysis of their magnetic properties at the individual nanowire level remains challenging. With this background, herein, we investigated the characterization of magnetic nanowires at room temperature under ambient conditions based on magnetic images obtained via wide-field quantum microscopy with nitrogen-vacancy centers in diamond. Consequently, we could extract critical magnetic properties, such as the saturation magnetization and coercivity, of single nanowires by comparing the experimental results with those of micromagnetic simulations. This study opens up the possibility for a versatile characterization method suited to individual magnetic nanowires. © 2023, CC BY.

关键词： Diamonds

The connection between polymer collapse and the onset of jamming

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arXiv 2023年

作者： Grigas, Alex T. Fisher, Aliza Shattuck, Mark D. O’Hern, Corey S. Graduate Program in Computational Biology and Bioinformatics Yale University New HavenCT06520 United States Integrated Graduate Program in Physical and Engineering Biology Yale University New HavenCT06520 United States Department of Mechanical Engineering and Materials Science Yale University New HavenCT06520 United States Benjamin Levich Institute and Physics Department The City College of New York New YorkNY10031 United States Department of Physics Yale University New HavenCT06520 United States Department of Applied Physics Yale University New HavenCT06520 United States

Previous studies have shown that the interiors of proteins are densely packed, reaching packing fractions that are as large as those found for static packings of individual amino-acid-shaped particles. How can the interiors of proteins take on such high packing fractions given that amino acids are connected by peptide bonds and many amino acids are hydrophobic with attractive interactions? We investigate this question by comparing the structural and mechanical properties of collapsed attractive disk-shaped bead-spring polymers to those of three reference systems: static packings of repulsive disks, of attractive disks, and of repulsive disk-shaped bead-spring polymers. We show that attractive systems quenched to temperatures below the glass transition T Tg and static packings of both repulsive disks and bead-spring polymers possess similar interior packing fractions. Previous studies have shown that static packings of repulsive disks are isostatic at jamming onset, i.e. the number of contacts Nc matches the number of degrees of freedom, which strongly influences their mechanical properties. We find that repulsive polymers are hypostatic at jamming onset, but effectively isostatic when including quartic modes. While attractive disk and polymer packings are hyperstatic, we identify a definition for interparticle contacts for which they can also be considered as effectively isostatic. As a result, we show that the mechanical properties (e.g. scaling of the potential energy with excess contact number and low-frequency contribution to the density of vibrational modes) of weakly attractive disk and polymer packings are similar to those of isostatic repulsive disk and polymer packings. Our results demonstrate that static packings generated via attractive collapse or compression of repulsive particles possess similar structural and mechanical properties. © 2023, CC BY.

关键词： Amino acids

Graphene Terahertz Devices for Sensing and Communication

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arXiv 2024年

作者： Samaha, Anna-Christina Doumani, Jacques Kritzell, T. Elijah Xu, Hongjing Baydin, Andrey Ajayan, Pulickel M. Tahchi, Mario El Kono, Junichiro Laboratory of Biomaterials and Intelligent Materials Department of Physics Faculty of Sciences 2 Lebanese University P.O. Box 90656 Jdeidet Lebanon Department of Electrical and Computer Engineering Rice University 6100 Main Street HoustonTX77005 United States Applied Physics Graduate Program Smalley–Curl Institute Rice University 6100 Main Street HoustonTX77005 United States Department of Physics and Astronomy Rice University 6100 Main Street HoustonTX77005 United States Smalley–Curl Institute Rice University 6100 Main Street HoustonTX77005 United States Department of Materials Science and NanoEngineering Rice University 6100 Main Street HoustonTX77005 United States Carbon Hub Rice University 6100 Main Street HoustonTX77005 United States

Graphene-based terahertz (THz) devices have emerged as promising platforms for a variety of applications, leveraging graphene’s unique optoelectronic properties. This review explores recent advancements in utilizing graphene in THz technology, focusing on two main aspects: THz molecular sensing and THz wave modulation. In molecular sensing, the environment-sensitive THz transmission and emission properties of graphene are utilized for enabling molecular adsorption detection and biomolecular sensing. This capability holds significant potential, from the detection of pesticides to DNA at high sensitivity and selectivity. In THz wave modulation, crucial for next-generation wireless communication systems, graphene demonstrates remarkable potential in absorption modulation when gated. Novel device structures, spectroscopic systems, and metasurface architectures have enabled enhanced absorption and wave modulation. Furthermore, techniques such as spatial phase modulation and polarization manipulation have been explored. From sensing to communication, graphene-based THz devices present a wide array of opportunities for future research and development. Finally, advancements in sensing techniques not only enhance biomolecular analysis but also contribute to optimizing graphene’s properties for communication by enabling efficient modulation of electromagnetic waves. Conversely, developments in communication strategies inform and enhance sensing capabilities, establishing a mutually beneficial relationship. © 2024, CC BY.

关键词： Graphene

Gallium Oxide as Photonic Integrated Platforms in the UV–Visible Spectra

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Gallium Oxide as Photonic Integrated Platforms in the UV–Vi...

Conference on Lasers and Electro-Optics (CLEO)

作者： Jingan Zhou Xuan Zhao Rui Xu Xiang Zhang Kai Fu Tao Li Mingfei Xu Shisong Luo Ziyi He Jacob T. Robinson Hanyu Zhu Pulickel M. Ajayan Xiaodong Zhang Yuji Zhao Department of Electrical and Computer Engineering Rice University Houston TX USA Applied Physics Graduate Program Smalley-Curl Institute Rice University Houston TX USA Department of Materials Science and NanoEngineering Rice University Houston TX USA School of Electrical Computer and Energy Engineering Arizona State University Tempe Arizona USA Nanofabrication Facility Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou China

We report the Ga 2 O 3 as photonic integrated platforms and its nonlinear optical effects in the UV–visible spectra. A low propagation loss of 3.7 dB/cm and second-order susceptibility of χ (2) =4.89×10 -3 pm... 详细信息

ISBN: (纸本)9781957171258

关键词： Material properties Nonlinear effects Nonlinear susceptibility Optical components Thin films Visible light communications