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Articles 1 - 30 of 371
Full-Text Articles in Physical Sciences and Mathematics
Single-Stage Few-Cycle Pulse Amplification, Sagnik Ghosh, Nathan G. Drouillard, Tj Hammond
Single-Stage Few-Cycle Pulse Amplification, Sagnik Ghosh, Nathan G. Drouillard, Tj Hammond
Physics Publications
Kerr instability can be exploited to amplify visible, near-infrared, and midinfrared ultrashort pulses. We use the results of Kerr instability amplification theory to inform our simulations amplifying few-cycle pulses. We show that the amplification angle dependence is simplified to the phase-matching condition of four-wave mixing when the intense pump is considered. Seeding with few-cycle pulses near the pump leads to broadband amplification without spatial chirp, while longer pulses undergo compression through amplification. Pumping in the midinfrared leads to multioctave spanning amplified pulses with single-cycle duration not previously predicted. We discuss limitations of the amplification process and optimizing pump and seed …
Spectral Broadening For Pulse Compression Using Liquid Alcohols, Jacob A. Stephen, Chathurangani J. Arachchige, Tj Hammond
Spectral Broadening For Pulse Compression Using Liquid Alcohols, Jacob A. Stephen, Chathurangani J. Arachchige, Tj Hammond
Physics Publications
Although gases, and more recently solids, have been used to create few-cycle pulses, we explore using liquid alcohols for spectral broadening and femtosecond pulse compression. By using a series of 1 cm cuvettes filled with 1-decanol, we have compressed a pulse from 83.6 fs down to 31.3 fs with a spectrum capable of supporting 25 fs pulses without filamentation.We measure the nonlinear index of refraction for various liquids, measuring n2 = (6.8 ± 0.5) × 10−20 m2 W−1 for 1-decanol.We demonstrate liquids to be a compact, simple, versatile, and cost-effective material to obtain broad spectra.
Measurement Of Dispersion And Index Of Refraction Of 1-Decanol With Spectrally Resolved White Light Interferometry, Nathan G. Drouillard, Tj Hammond
Measurement Of Dispersion And Index Of Refraction Of 1-Decanol With Spectrally Resolved White Light Interferometry, Nathan G. Drouillard, Tj Hammond
Physics Publications
The high density, high nonlinearity, and stability of liquids make them an attractive medium for spectral broadening and supercontinuum generation in ultrafast experiments. To understand ultrashort pulse propagation in these media, their indices of refraction and dispersions must be characterized. We employ a Mach-Zehnder interferometer to generate a series of interferograms, which we refer to as a spectrogram, to develop a new method of using spectrally resolved white light interferometry to determine the refractive indices of materials. We determine the indices of refraction of BK7, sapphire, ethanol, and 1-decanol at 24°C across the visible and near infrared. To our knowledge, …
Morphological Analysis Of Size And Shape (Mass): An Integrative Software Program For Morphometric Analyses Of Leaves, Tya S. Chuanromanee, James I. Cohen, Gillian L. Ryan
Morphological Analysis Of Size And Shape (Mass): An Integrative Software Program For Morphometric Analyses Of Leaves, Tya S. Chuanromanee, James I. Cohen, Gillian L. Ryan
Physics Publications
Morphometric analysis is a common approach for comparing and categorizing botanical samples; however, completing a suite of analyses using existing tools may require a multi-stage, multi-program process. To facilitate streamlined analysis within a single program, Morphological Analysis of Size and Shape (MASS) for leaves was developed. Its utility is demonstrated using exemplar leaf samples from Acer saccharum, Malus domestica, and Lithospermum.
A Simple And Efficient Centrifugation Filtration Method For Bacterial Concentration And Isolation Prior To Testing Liquid Specimens With Laser-Induced Breakdown Spectroscopy, Dylan J. Malenfanta, Alexandra E. Paulick, Steven J. Rehse
A Simple And Efficient Centrifugation Filtration Method For Bacterial Concentration And Isolation Prior To Testing Liquid Specimens With Laser-Induced Breakdown Spectroscopy, Dylan J. Malenfanta, Alexandra E. Paulick, Steven J. Rehse
Physics Publications
An inexpensive filtration device was designed and constructed to rapidly concentrate bacteria in a liquid suspension on the surface of a disposable filter medium while at the same time separating the bacterial cells from larger contaminants in the suspension on the basis of their size. The device consists of a two-stage insert that is held rigidly in a standard tube during bacterial suspension centrifugation. The filters can be easily removed from the insert for subsequent testing with laser-induced breakdown spectroscopy in a process that takes only three minutes. Filter media of 0.45 micron pore size was found to capture approximately …
Concentration Of Bacterial Specimens During Centrifugation Prior To Laser-Induced Breakdown Spectroscopy Analysis, Alexandra E. Paulicka, Dylan J. Malenfanta, Steven J. Rehse
Concentration Of Bacterial Specimens During Centrifugation Prior To Laser-Induced Breakdown Spectroscopy Analysis, Alexandra E. Paulicka, Dylan J. Malenfanta, Steven J. Rehse
Physics Publications
A metal cone device has been designed and fabricated for use with a custom centrifuge tube insert to allow the simple and rapid concentration of bacterial cells in a circular area with a diameter of 1 mm. The device concentrates cells suspended in up to 1 mL of liquid at the center of a highly flat disposable filter medium which can be easily removed from the centrifuge tube insert for subsequent testing with laser-induced breakdown spectroscopy. Two-dimensional elemental mapping of the filter evidenced a high concentration of bacteria on the filter under the location of the cone hole, as well …
A Review Of The Use Of Laser-Induced Breakdown Spectroscopy For Bacterial Classification, Quantification, And Identification, Steven J. Rehse
A Review Of The Use Of Laser-Induced Breakdown Spectroscopy For Bacterial Classification, Quantification, And Identification, Steven J. Rehse
Physics Publications
The use of laser-induced breakdown spectroscopy to determine the elemental composition of bacterial cells has been described in the peer-reviewed literature since 2003. Fifteen years on, significant accomplishments have been reported that have served to clarify and underscore the areas of bacteriological investigation that LIBS is well-suited for as well as the challenges that yet remain to be faced. This review will attempt to summarize the state of the field by surveying the available body of knowledge. The early days of these experiments, roughly from 2003 to 2007, in which many of the most fundamental experiments were initially conducted will …
Helium Tune-Out Wavelength: Gauge Invariance And Retardation Corrections, Gordon W. F. Drake, Jacob Gabriel Manalo, Pei-Pei Zhang, Kenneth George Herbert Baldwin
Helium Tune-Out Wavelength: Gauge Invariance And Retardation Corrections, Gordon W. F. Drake, Jacob Gabriel Manalo, Pei-Pei Zhang, Kenneth George Herbert Baldwin
Physics Publications
The problem of calculating the tune-out wavelength for an atom interacting with a plane electromagnetic wave is formulated as a zero in the Rayleigh scattering cross section, rather than a zero in the dynamic polarizability. Retardation (finite wavelength) corrections are discussed in the velocity gauge, and possible gauge transformations to a length form are investigated. For the special case of S-states, it is shown that a pure length form exists for the leading pxz retardation correction, even though one does not exist in general. The results of high-precision calculations in Hylleraas coordinates are presented for the tune-out wavelength of …
Reduced Graphene Oxide On Nickel Foam For Supercapacitor Electrodes, Uma Ramabadran, Gillian Ryan, Xuan Zhou, Susan Farhat, Felicia Manciu, Yigang Tong, Ryan Ayler, Graham Garner
Reduced Graphene Oxide On Nickel Foam For Supercapacitor Electrodes, Uma Ramabadran, Gillian Ryan, Xuan Zhou, Susan Farhat, Felicia Manciu, Yigang Tong, Ryan Ayler, Graham Garner
Physics Publications
The focus of this paper is the investigation of reduced graphene oxide (GO)/nickel foam (RGON) samples for use as supercapacitor electrodes. Nickel foam samples were soaked in a GO suspension and dried before being subjected to two different methods to remove oxygen. Atmospheric pressure annealed (APA) samples were treated with a varying number (10–18) of nitrogen plasma jet scans, where sample temperatures did not exceed 280 °C. Furnace annealed (FA) samples were processed in an atmosphere of hydrogen and argon, at temperatures ranging from 600 °C to 900 °C. Environmental Scanning Electron Microscope (ESEM) data indicated that …
N (2p) Production In Electron-N2 Collisions, Wladyslaw Kedzierski, Jeff Dech, J. W. Mcconkey
N (2p) Production In Electron-N2 Collisions, Wladyslaw Kedzierski, Jeff Dech, J. W. Mcconkey
Physics Publications
A unique detector which is selectively sensitive to low energy metastable atoms, has been used to study the production of ground state N (2P) atoms following collisions of low energy (0-200 eV) electrons with molecular nitrogen. TOF techniques have revealed the existence of at least two distinct mechanisms yielding this dissociation product. Released kinetic energies in the dissociation have allowed positioning of the parent molecular states in the Franck-Condon region. This has allowed probable parent states, such as B' 3Σu¯, b' 1Σu+ and C' 3Πu, to be identified making use of recent theoretical calculations. Both direct and predissociation processes are …
Determination Of The Zinc Concentration In Human Fingernails By Laser-Induced Breakdown Spectroscopy, Steven J. Rehse, Vlora A. Riberdy, Christopher J. Frederickson
Determination Of The Zinc Concentration In Human Fingernails By Laser-Induced Breakdown Spectroscopy, Steven J. Rehse, Vlora A. Riberdy, Christopher J. Frederickson
Physics Publications
The absolute concentration of zinc in human fingernail clippings tested ex vivo was determined by 1064 nm laser-induced breakdown spectroscopy and confirmed by speciated isotope dilution mass spectrometry. A nail testing protocol that sampled across the nail (perpendicular to the direction of growth) was developed and validated by scanning electron microscopy energy dispersive x-ray spectroscopy. Using this protocol, a partial least squares regression model predicted the zinc concentration in five subjects’ fingernails to within 7 ppm on average. The variation of the zinc concentration with depth into the nail as determined by laser-induced breakdown spectroscopy was studied and found to …
Rational Design Of Super-Alkalis And Their Role In Co2 Activation, Tianshan Zhao, Qian Wang, Puru Jena
Rational Design Of Super-Alkalis And Their Role In Co2 Activation, Tianshan Zhao, Qian Wang, Puru Jena
Physics Publications
Super-alkalis are clusters of atoms. With ionization potentials smaller than those of the alkali atoms, they are playing an increasing role in chemistry as highlighted by recent applications in solar cells as well as in Li-ion batteries. For the past 40 years superalkalis were designed using inorganic elements with the sp orbital character. Here, we show that a large class of superalkalis composed of only simple metal atoms, transition metal complexes as well as organic molecules can be designed by making use of electron counting rules beyond the octet rule. Examples include Al-3(+), Mn(B3N3H6)(2)(+), B9C3H12+, and C5NH6+ which obey the …
B-12(Scn)(12)(-): An Ultrastable Weakly Coordinating Dianion, Hong Fang, Puru Jena
B-12(Scn)(12)(-): An Ultrastable Weakly Coordinating Dianion, Hong Fang, Puru Jena
Physics Publications
Stable dianions that are weakly coordinating with metal ions are not common. In this work, we show that the thiocyanate SCN- anion, known for its detoxification property of cyanide CN- and antidegradation property of perovskite solar cell materials, can also be used to produce a new set of weakly coordinating B-12(SCN)(12)(-) dianion complexes which are potential candidates for the anionic part inside the electrolytes of metal-ion, especially the magnesium-ion-based, batteries.
Metal Chalcogenide Clusters With Closed Electronic Shells And The Electronic Properties Of Alkalis And Halogens, Vikas Chauhan, Arthur C. Reber, Shiv N. Khanna
Metal Chalcogenide Clusters With Closed Electronic Shells And The Electronic Properties Of Alkalis And Halogens, Vikas Chauhan, Arthur C. Reber, Shiv N. Khanna
Physics Publications
Clusters with filled electronic shells and a large gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are generally energetically and chemically stable. Enabling clusters to become electron donors with low ionization energies or electron acceptors with high electron affinities usually requires changing the valence electron count. Here we demonstrate that a metal cluster may be transformed from an electron donor to an acceptor by exchanging ligands while the neutral form of the clusters has closed electronic shells. Our studies on Co6Te8(PEt3),(CO) (m + n = 6) clusters show that Co6Te8(PEt3)(6) has a closed …
Symmetry And Magnetism In Ni9te6 Clusters Ligated By Co Or Phosphine Ligands, Arthur C. Reber, Vikas Chauhan, Shiv N. Khanna
Symmetry And Magnetism In Ni9te6 Clusters Ligated By Co Or Phosphine Ligands, Arthur C. Reber, Vikas Chauhan, Shiv N. Khanna
Physics Publications
The removal of a single ligand from the magnetic Ni9Te6(L)(8) (L = P(CH3)(3), CO) clusters is found to quench the magnetic moment. The reduction in magnetic moment is caused by a geometric deformation of the Ni9Te6 core that breaks the octahedral symmetry of the cluster. This effect is observed in both the CO and phosphine based ligands. The octahedral symmetry bare cluster is also found to have a large magnetic moment. These results highlight the dilemma faced by magnetic ligand protected clusters whose symmetry has been broken: whether to break the spin symmetry as in Hund's rules or to break …
The Effect Of Substituted Benzene Dicarboxylic Acid Linkers On The Optical Band Gap Energy And Magnetic Coupling In Manganese Trimer Metal Organic Frameworks, K. S. Asha, Arthur C. Reber, N. Ahmed, R. Nath, Shiv N. Khanna, Sukhendu Mandal
The Effect Of Substituted Benzene Dicarboxylic Acid Linkers On The Optical Band Gap Energy And Magnetic Coupling In Manganese Trimer Metal Organic Frameworks, K. S. Asha, Arthur C. Reber, N. Ahmed, R. Nath, Shiv N. Khanna, Sukhendu Mandal
Physics Publications
We have systematically studied a series of eight metal-organic frameworks (MOFs) in which the secondary building unit is a manganese trimer cluster, and the linkers are differently substituted benzene dicarboxylic acids (BDC). The optical band gap energy of the compounds vary from 2.62 eV to 3.57 eV, and theoretical studies find that different functional groups result in new states in the conduction band, which lie in the gap and lower the optical band gap energy. The optical absorption between the filled Mn 3d states and the ligands is weak due to minimal overlap of the states, and the measured optical …
Evolution Of The Spin Magnetic Moments And Atomic Valence Of Vanadium In Vcux+, Vagx+, And Vaux+ Clusters (X = 3–14), William H. Blades, Arthur C. Reber, Shiv N. Khanna, Luis López-Sosa, Patrizia Calaminici, Andreas M. Köster
Evolution Of The Spin Magnetic Moments And Atomic Valence Of Vanadium In Vcux+, Vagx+, And Vaux+ Clusters (X = 3–14), William H. Blades, Arthur C. Reber, Shiv N. Khanna, Luis López-Sosa, Patrizia Calaminici, Andreas M. Köster
Physics Publications
The atomic structures, bonding characteristics, spin magnetic moments, and stability of VCUx+, VAgx+, and VAux+ (x = 3-14) clusters were examined using density functional theory. Our studies indicate that the effective valence of vanadium is size-dependent and that at small sizes some of the valence electrons of vanadium are localized on vanadium, while at larger sizes the 3d orbitals of the vanadium participate in metallic bonding eventually quenching the spin magnetic moment. The electronic stability of the clusters may be understood through a split-shell model that partitions the valence electrons in either a delocalized shell or localized on the vanadium …
Use Of Solid N2 Surfaces In Metastable Particle Detection, Wladyslaw Kedzierski, J. W. Mcconkey
Use Of Solid N2 Surfaces In Metastable Particle Detection, Wladyslaw Kedzierski, J. W. Mcconkey
Physics Publications
A novel detector is described in which solid nitrogen at 17 K is used as the most significant element. Metastable particles impinge on this element and immediately transfer their internal energy to the solid nitrogen producing photons, via excimer formation or otherwise, whose wavelength depends on the metastable being detected and the energy transfer process. The performance of the instrument for the detection of atomic oxygen and molecular nitrogen metastables is discussed.
Extracting Vibration Characteristics Of A Guitar Using Finite Element, Modal Analysis, And Digital Image Correlation Techniques, Kiran Patil, Javad Baqersad, Daniel Ludwigsen, Yaomin Dong
Extracting Vibration Characteristics Of A Guitar Using Finite Element, Modal Analysis, And Digital Image Correlation Techniques, Kiran Patil, Javad Baqersad, Daniel Ludwigsen, Yaomin Dong
Physics Publications
The sound quality generated by the guitar depends on the vibration characteristics (i.e. natural frequencies and mode shapes) of this instrument. Thus, it is of particular interest to the guitar manufacturers to be able to obtain global information about the characteristics of the guitar. Traditional sensors can only measure at discrete locations. However, digital image correlation (DIC) can measure full-field data on the surface of the structure. In the current paper, a finite element (FE) model of a guitar with free boundary configurations was developed using quadratic solid elements. An eigensolution was performed on the FE model to determine its …
Selective Detection Of Singlet Gerade Metastable States Of N-2, Wladyslaw Kedzierski, J. W. Mcconkey
Selective Detection Of Singlet Gerade Metastable States Of N-2, Wladyslaw Kedzierski, J. W. Mcconkey
Physics Publications
Metastable N-2 molecules produced by electron impact on N2 are detected using a unique solid nitrogen matrix detector. The time-of-flight system is shown to be selectively sensitive to a(1)Pi(g) and (1)Sigma(+)(g) or (1)Gamma(g) metastable species. The latter species had been identified theoretically previously but was detected experimentally for the first time in the present investigation. Their identification and excitation as a function of electron energy from threshold to 300 eV are presented. Comparison is made with the data obtained by other techniques. Published by AIP Publishing.
Vuv Study Of Electron Impact Dissociative Excitation Of Thymine, C. J. Tiessen, J. A. Trocchi, J. D. Hein, J. Dech, Wladyslaw Kedzierski, J. W. Mcconkey
Vuv Study Of Electron Impact Dissociative Excitation Of Thymine, C. J. Tiessen, J. A. Trocchi, J. D. Hein, J. Dech, Wladyslaw Kedzierski, J. W. Mcconkey
Physics Publications
Dissociative excitation of thymine following electron impact was studied in the energy range up to 430 eV. Emissions in the vacuum ultra-violet spectral region below 150 nm were studied and found to be dominated by the hydrogen Lyman series. Emission cross section data reveal that Lyman-α excitation displays a broad maximum at an electron impact energy of 160 eV. The probability of extracting other excited atoms from the parent molecule is found to be insignificant. Possible excitation and dissociation mechanisms in the parent molecule are discussed.
Tuning The Plasmonic Properties Of Silver Nanopatterns Fabricated By Shadow Nanosphere Lithography, Whitney Ingram, Yizhuo He, Keenan Stone, William M. Dennis, Dexian Ye, Yiping Zhao
Tuning The Plasmonic Properties Of Silver Nanopatterns Fabricated By Shadow Nanosphere Lithography, Whitney Ingram, Yizhuo He, Keenan Stone, William M. Dennis, Dexian Ye, Yiping Zhao
Physics Publications
Regular silver (Ag) nanopatterns, from disconnected nanotriangles to well coupled triangular clusters of nanoparticles, were prepared by shadow nanosphere lithography at different incident angles θ from 0 degrees to 20 degrees with continuous azimuthal rotation. The resulting nanopatterns were consistent with predictions by numerical calculations and Monte Carlo simulations of adatoms with high diffusivity. The visible localized surface plasmon resonance of these nanopatterns was tuned by θ systematically due to the change in size, shape, and arrangement of Ag nanopatterns. These resonances were consistent with finite-difference time-domain simulations using realistic nanopatterns based upon scanning electron micrographs. Such a simple fabrication …
Latent Heat Recovery Modification From Sodium Acetate Trihydrate Due To Structural Changes Caused By Silver Nanoparticles, Gillian Ryan, Uma Ramabadran, Frederick Garcia
Latent Heat Recovery Modification From Sodium Acetate Trihydrate Due To Structural Changes Caused By Silver Nanoparticles, Gillian Ryan, Uma Ramabadran, Frederick Garcia
Physics Publications
Phase change materials (PCMs) have great potential as energy storage devices through the storage of thermal energy at low temperatures. Sodium acetate trihydrate (SAT) is a PCM commonly used for storing thermal energy for non-electric personal warmers, and releases that energy as latent heat during the phase transition from a supersaturated liquid state to a solid, crystal state at room temperature. SAT is an inexpensive, non-toxic PCM. These characteristics make SAT ideal for the development of reusable, non-electric neonatal blankets. This application requires careful optimization of the maximum temperature attained by the SAT solution, balanced by a prolonged heat release …
Cellular Hokey Pokey: A Coarse-Grained Model Of Lamellipodia Protrusion Dynamics Driven By Fluctuations In Actin Polymerization, Gillian Ryan, Dimitrios Vavylonis, Naoki Watanabe
Cellular Hokey Pokey: A Coarse-Grained Model Of Lamellipodia Protrusion Dynamics Driven By Fluctuations In Actin Polymerization, Gillian Ryan, Dimitrios Vavylonis, Naoki Watanabe
Physics Publications
Animal cells that spread onto a surface often rely on actin-rich cell extensions called lamellipodia to execute cell protrusion. XTC cells on a two-dimensional substrate exhibit regular protrusion and retraction of their lamellipodium, even though the cell is not translating. Travelling waves of protrusion have also been observed, similar to those observed in crawling cells. These periodic fluctuations in leading edge position have been linked to excitable actin dynamics near the cell edge using a one dimensional model of actin dynamics, as a function of arc-length along the cell. In this work we extend this earlier model of actin dynamics …
A Method For Measuring The Néel Relaxation Time In A Frozen Ferrofluid, Ronald J. Tackett, Jagdish Thakur, Nathaniel Mosher, Emily Perkins-Harbin, Ronald E. Kumon, Lihua Wang, Corneliu Rablau, Prem P. Vaishnava
A Method For Measuring The Néel Relaxation Time In A Frozen Ferrofluid, Ronald J. Tackett, Jagdish Thakur, Nathaniel Mosher, Emily Perkins-Harbin, Ronald E. Kumon, Lihua Wang, Corneliu Rablau, Prem P. Vaishnava
Physics Publications
We report a novel method of determining the average Néel relaxation time and its temperature dependence by calculating derivatives of the measured time dependence of temperature for a frozen ferrofluid exposed to an alternating magnetic field. The ferrofluid, composed of dextran-coated Fe3O4 nanoparticles (diameter 13.7 nm ± 4.7 nm), was synthesized via wet chemical precipitation and characterized by x-ray diffraction and transmission electron microscopy. An alternating magnetic field of constant amplitude (H0=20H0=20 kA/m) driven at frequencies of 171 kHz, 232 kHz, and 343 kHz was used to determine the temperature dependent magnetic energy absorption rate in the temperature range from …
A New Silicon Phase With Direct Band Gap And Novel Optoelectronic Properties, Yaguang Guo, Qian Wang, Yoshiyuki Kawazoe, Puru Jena
A New Silicon Phase With Direct Band Gap And Novel Optoelectronic Properties, Yaguang Guo, Qian Wang, Yoshiyuki Kawazoe, Puru Jena
Physics Publications
Due to the compatibility with the well-developed Si-based semiconductor industry, there is considerable interest in developing silicon structures with direct energy band gaps for effective sunlight harvesting. In this paper, using silicon triangles as the building block, we propose a new silicon allotrope with a direct band gap of 0.61 eV, which is dynamically, thermally and mechanically stable. Symmetry group analysis further suggests that dipole transition at the direct band gap is allowed. In addition, this new allotrope displays large carrier mobility (~104 cm/V · s) at room temperature and a low mass density (1.71 g/cm3), making …
Using Graphene To Control Magnetic Anisotropy And Interaction Between Supported Clusters, Sanjubala Sahoo, M Fhokrul Islam, Shiv N. Khanna
Using Graphene To Control Magnetic Anisotropy And Interaction Between Supported Clusters, Sanjubala Sahoo, M Fhokrul Islam, Shiv N. Khanna
Physics Publications
Stabilization of magnetic order in clusters/nanoparticles at elevated temperatures is a fundamentally challenging problem. The magnetic anisotropy energy (MAE) that prevents the thermal fluctuations of the magnetization direction can be around 1–10 K in free transition metal clusters of around a dozen atoms. Here we demonstrate that a graphene support can lead to an order of magnitude enhancement in the anisotropy of supported species. Our studies show that the MAE of supported Co5 and Co13 clusters on graphene increase by factors of 2.6 and 25, respectively. The enhancement is linked to the splitting of selected electronic orbitals that leads to …
New Single-Molecule Speckle Microscopy Reveals Modification Of The Retrograde Actin Flow By Focal Adhesions At Nanometer Scales, Sawako Yamashiro, Hiroaki Mizuno, Matthew B. Smith, Gillian L. Ryan, Tai Kiuchi, Dimitrios Vavylonis, Naoki Watanabe
New Single-Molecule Speckle Microscopy Reveals Modification Of The Retrograde Actin Flow By Focal Adhesions At Nanometer Scales, Sawako Yamashiro, Hiroaki Mizuno, Matthew B. Smith, Gillian L. Ryan, Tai Kiuchi, Dimitrios Vavylonis, Naoki Watanabe
Physics Publications
Speckle microscopy directly visualizes the retrograde actin flow, which is believed to promote cell-edge protrusion when linked to focal adhesions (FAs). However, it has been argued that, due to rapid actin turnover, the use of green fluorescent protein–actin, the lack of appropriate analysis algorithms, and technical difficulties, speckle microscopy does not necessarily report the flow velocities of entire actin populations. In this study, we developed a new, user-friendly single-molecule speckle (SiMS) microscopy using DyLight dye-labeled actin. Our new SiMS method enables in vivo nanometer-scale displacement analysis with a low localization error of ±8–8.5 nm, allowing accurate flow-velocity measurement for actin …
Advances In Atomic, Molecular, And Optical Physics, J. W. Mcconkey, Wladyslaw Kedzierski
Advances In Atomic, Molecular, And Optical Physics, J. W. Mcconkey, Wladyslaw Kedzierski
Physics Publications
The use of rare gas matrices for the detection of a variety of low-energy metastable species, particularly those from atoms with an np4 outer electron configuration, is discussed in detail. The historical development of the detector is outlined and its performance as a function of rare gas, matrix temperature, and metastable species is discussed. Examples of its use are given for electron impact dissociation of a wide variety of oxygen and sulfur containing targets.
18-Electron Rule Inspired Zintl-Like Ions Composed Of All Transition Metals, Jian Zhou, Santanab Giri, Purusottam Jena
18-Electron Rule Inspired Zintl-Like Ions Composed Of All Transition Metals, Jian Zhou, Santanab Giri, Purusottam Jena
Physics Publications
Zintl phase compounds constitute a unique class of compounds composed of metal cations and covalently bonded multiply charged cluster anions. Potential applications of these materials in solution chemistry and thermoelectric materials have given rise to renewed interest in the search for new Zintl ions. Up to now these ions have been mostly composed of group 13, 14, and 15 post-transition metal elements and no Zintl ions composed of all transition metal elements are known. Using gradient corrected density functional theory we show that the 18-electron rule can be applied to design a new class of Zintl-like ions composed of all …