Simulating Nucleic Acids from Nanoseconds to Microseconds
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Time and Frequency Users' Manual
,>'.)*• r>rJfl HKra mitt* >\ « i If I * I IT I . Ip I * .aference nbs Publi- cations / % ^m \ NBS TECHNICAL NOTE 695 U.S. DEPARTMENT OF COMMERCE/National Bureau of Standards Time and Frequency Users' Manual 100 .U5753 No. 695 1977 NATIONAL BUREAU OF STANDARDS 1 The National Bureau of Standards was established by an act of Congress March 3, 1901. The Bureau's overall goal is to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit To this end, the Bureau conducts research and provides: (1) a basis for the Nation's physical measurement system, (2) scientific and technological services for industry and government, a technical (3) basis for equity in trade, and (4) technical services to pro- mote public safety. The Bureau consists of the Institute for Basic Standards, the Institute for Materials Research the Institute for Applied Technology, the Institute for Computer Sciences and Technology, the Office for Information Programs, and the Office of Experimental Technology Incentives Program. THE INSTITUTE FOR BASIC STANDARDS provides the central basis within the United States of a complete and consist- ent system of physical measurement; coordinates that system with measurement systems of other nations; and furnishes essen- tial services leading to accurate and uniform physical measurements throughout the Nation's scientific community, industry, and commerce. The Institute consists of the Office of Measurement Services, and the following center and divisions: Applied Mathematics -
The Impact of the Speed of Light on Financial Markets and Their Regulation
When Finance Meets Physics: The Impact of the Speed of Light on Financial Markets and their Regulation by James J. Angel, Ph.D., CFA Associate Professor of Finance McDonough School of Business Georgetown University 509 Hariri Building Washington DC 20057 USA 1.202.687.3765 [email protected] The Financial Review, Forthcoming, May 2014 · Volume 49 · No. 2 Abstract: Modern physics has demonstrated that matter behaves very differently as it approaches the speed of light. This paper explores the implications of modern physics to the operation and regulation of financial markets. Information cannot move faster than the speed of light. The geographic separation of market centers means that relativistic considerations need to be taken into account in the regulation of markets. Observers in different locations may simultaneously observe different “best” prices. Regulators may not be able to determine which transactions occurred first, leading to problems with best execution and trade- through rules. Catastrophic software glitches can quantum tunnel through seemingly impregnable quality control procedures. Keywords: Relativity, Financial Markets, Regulation, High frequency trading, Latency, Best execution JEL Classification: G180 The author is also on the board of directors of the Direct Edge stock exchanges (EDGX and EDGA). I wish to thank the editor and referee for extremely helpful comments and suggestions. I also wish to thank the U.K. Foresight Project, for providing financial support for an earlier version of this paper. All opinions are strictly my own and do not necessarily represent those of Georgetown University, Direct Edge, the U.K. Foresight Project, The Financial Review, or anyone else for that matter. -
Using Microsecond Single-Molecule FRET to Determine the Assembly
Using microsecond single-molecule FRET to determine PNAS PLUS the assembly pathways of T4 ssDNA binding protein onto model DNA replication forks Carey Phelpsa,b,1, Brett Israelsa,b, Davis Josea, Morgan C. Marsha,b, Peter H. von Hippela,2, and Andrew H. Marcusa,b,2 aDepartment of Chemistry and Biochemistry, Institute of Molecular Biology, University of Oregon, Eugene, OR 97403; and bDepartment of Chemistry and Biochemistry, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, Eugene, OR 97403 Edited by Stephen C. Kowalczykowski, University of California, Davis, CA, and approved March 20, 2017 (received for review December 2, 2016) DNA replication is a core biological process that occurs in pro- complete coverage of the exposed ssDNA templates at the precisely karyotic cells at high speeds (∼1 nucleotide residue added per regulated concentration of protein that needs to be maintained in millisecond) and with high fidelity (fewer than one misincorpora- the infected Escherichia coli cell (8, 9). The gp32 protein has an tion event per 107 nucleotide additions). The ssDNA binding pro- N-terminal domain, a C-terminal domain, and a core domain. tein [gene product 32 (gp32)] of the T4 bacteriophage is a central The N-terminal domain is necessary for the cooperative binding integrating component of the replication complex that must con- of the gp32 protein through its interactions with the core domain of tinuously bind to and unbind from transiently exposed template an adjacent gp32 protein. To bind to ssDNA, the C-terminal domain strands during DNA synthesis. We here report microsecond single- of the gp32 protein must undergo a conformational change that molecule FRET (smFRET) measurements on Cy3/Cy5-labeled primer- exposes the positively charged region of its core domain, which in template (p/t) DNA constructs in the presence of gp32. -
Aquatic Primary Productivity Field Protocols for Satellite Validation and Model Synthesis (DRAFT)
Ocean Optics & Biogeochemistry Protocols for Satellite Ocean Colour Sensor Validation IOCCG Protocol Series Volume 7.0, 2021 Aquatic Primary Productivity Field Protocols for Satellite Validation and Model Synthesis (DRAFT) Report of a NASA-sponsored workshop with contributions (alphabetical) from: William M. Balch Bigelow Laboratory for Ocean Sciences, Maine, USA Magdalena M. Carranza Monterey Bay Aquarium Research Institute, California, USA Ivona Cetinic University Space Research Association, NASA Goddard Space Flight Center, Maryland, USA Joaquín E. Chaves Science Systems and Applications, Inc., NASA Goddard Space Flight Center, Maryland, USA Solange Duhamel University of Arizona, Arizona, USA Zachary K. Erickson University Space Research Association, NASA Goddard Space Flight Center, Maryland, USA Andrea J. Fassbender NOAA Pacific Marine Environmental Laboratory, Washington, USA Ana Fernández-Carrera Leibniz Institute for Baltic Sea Research Warnemünde, Rostock, Germany Sara Ferrón University of Hawaii at Manoa, Hawaii, USA E. Elena García-Martín National Oceanography Centre, Southampton, UK Joaquim Goes Lamont Doherty Earth Observatory at Columbia University, New York, USA Helga do Rosario Gomes Lamont Doherty Earth Observatory at Columbia University, New York, USA Maxim Y. Gorbunov Department of Marine and Coastal Sciences, Rutgers University, New Jersey, USA Kjell Gundersen Plankton Research Group, Institute of Marine Research, Bergen, Norway Kimberly Halsey Department of Microbiology, Oregon State University, Oregon, USA Toru Hirawake -
Nanosecond X-Ray Photon Correlation Spectroscopy Using Pulse Time
research papers Nanosecond X-ray photon correlation spectroscopy IUCrJ using pulse time structure of a storage-ring source ISSN 2052-2525 NEUTRONjSYNCHROTRON Wonhyuk Jo,a Fabian Westermeier,a Rustam Rysov,a Olaf Leupold,a Florian Schulz,b,c Steffen Tober,b‡ Verena Markmann,a Michael Sprung,a Allesandro Ricci,a Torsten Laurus,a Allahgholi Aschkan,a Alexander Klyuev,a Ulrich Trunk,a Heinz Graafsma,a Gerhard Gru¨bela,c and Wojciech Rosekera* Received 25 September 2020 Accepted 2 December 2020 aDeutsches Elektronen-Synchrotron (DESY), Notkestr. 85, 22607 Hamburg, Germany, bInstitute of Physical Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany, and cThe Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany. *Correspondence e-mail: [email protected] Edited by Dr T. Ishikawa, Coherent X-ray Optics Laboratory, Harima Institute, RIKEN, Japan X-ray photon correlation spectroscopy (XPCS) is a routine technique to study slow dynamics in complex systems at storage-ring sources. Achieving ‡ Current address: Deutsches Elektronen- Synchrotron (DESY), Notkestr. 85, 22607 nanosecond time resolution with the conventional XPCS technique is, however, Hamburg, Germany. still an experimentally challenging task requiring fast detectors and sufficient photon flux. Here, the result of a nanosecond XPCS study of fast colloidal Keywords: materials science; nanoscience; dynamics is shown by employing an adaptive gain integrating pixel detector SAXS; dynamical studies; time-resolved studies; (AGIPD) operated at frame rates of the intrinsic pulse structure of the storage X-ray photon correlation spectroscopy; adaptive ring. Correlation functions from single-pulse speckle patterns with the shortest gain integrating pixel detectors; storage rings; pulse structures. -
Guide for the Use of the International System of Units (SI)
Guide for the Use of the International System of Units (SI) m kg s cd SI mol K A NIST Special Publication 811 2008 Edition Ambler Thompson and Barry N. Taylor NIST Special Publication 811 2008 Edition Guide for the Use of the International System of Units (SI) Ambler Thompson Technology Services and Barry N. Taylor Physics Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899 (Supersedes NIST Special Publication 811, 1995 Edition, April 1995) March 2008 U.S. Department of Commerce Carlos M. Gutierrez, Secretary National Institute of Standards and Technology James M. Turner, Acting Director National Institute of Standards and Technology Special Publication 811, 2008 Edition (Supersedes NIST Special Publication 811, April 1995 Edition) Natl. Inst. Stand. Technol. Spec. Publ. 811, 2008 Ed., 85 pages (March 2008; 2nd printing November 2008) CODEN: NSPUE3 Note on 2nd printing: This 2nd printing dated November 2008 of NIST SP811 corrects a number of minor typographical errors present in the 1st printing dated March 2008. Guide for the Use of the International System of Units (SI) Preface The International System of Units, universally abbreviated SI (from the French Le Système International d’Unités), is the modern metric system of measurement. Long the dominant measurement system used in science, the SI is becoming the dominant measurement system used in international commerce. The Omnibus Trade and Competitiveness Act of August 1988 [Public Law (PL) 100-418] changed the name of the National Bureau of Standards (NBS) to the National Institute of Standards and Technology (NIST) and gave to NIST the added task of helping U.S. -
Low Latency – How Low Can You Go?
WHITE PAPER Low Latency – How Low Can You Go? Low latency has always been an important consideration in telecom networks for voice, video, and data, but recent changes in applications within many industry sectors have brought low latency right to the forefront of the industry. The finance industry and algorithmic trading in particular, or algo-trading as it is known, is a commonly quoted example. Here latency is critical, and to quote Information Week magazine, “A 1-millisecond advantage in trading applications can be worth $100 million a year to a major brokerage firm.” This drives a huge focus on all aspects of latency, including the communications systems between the brokerage firm and the exchange. However, while the finance industry is spending a lot of money on low- latency services between key locations such as New York and Chicago or London and Frankfurt, this is actually only a small part of the wider telecom industry. Many other industries are also now driving lower and lower latency in their networks, such as for cloud computing and video services. Also, as mobile operators start to roll out 5G services, latency in the xHaul mobile transport network, especially the demanding fronthaul domain, becomes more and more important in order to reach the stringent 5G requirements required for the new class of ultra-reliable low-latency services. This white paper will address the drivers behind the recent rush to low- latency solutions and networks and will consider how network operators can remove as much latency as possible from their networks as they also race to zero latency. -
Microsecond and Millisecond Dynamics in the Photosynthetic
Microsecond and millisecond dynamics in the photosynthetic protein LHCSR1 observed by single-molecule correlation spectroscopy Toru Kondoa,1,2, Jesse B. Gordona, Alberta Pinnolab,c, Luca Dall’Ostob, Roberto Bassib, and Gabriela S. Schlau-Cohena,1 aDepartment of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139; bDepartment of Biotechnology, University of Verona, 37134 Verona, Italy; and cDepartment of Biology and Biotechnology, University of Pavia, 27100 Pavia, Italy Edited by Catherine J. Murphy, University of Illinois at Urbana–Champaign, Urbana, IL, and approved April 11, 2019 (received for review December 13, 2018) Biological systems are subjected to continuous environmental (5–9) or intensity correlation function analysis (10). CPF analysis fluctuations, and therefore, flexibility in the structure and func- bins the photon data, obscuring fast dynamics. In contrast, inten- tion of their protein building blocks is essential for survival. sity correlation function analysis characterizes fluctuations in the Protein dynamics are often local conformational changes, which photon arrival rate, accessing dynamics down to microseconds. allows multiple dynamical processes to occur simultaneously and However, the fluorescence lifetime is a powerful indicator of rapidly in individual proteins. Experiments often average over conformation for chromoproteins and for lifetime-based FRET these dynamics and their multiplicity, preventing identification measurements, yet it is ignored in intensity-based analyses. of the molecular origin and impact on biological function. Green 2D fluorescence lifetime correlation (2D-FLC) analysis was plants survive under high light by quenching excess energy, recently introduced as a method to both resolve fast dynam- and Light-Harvesting Complex Stress Related 1 (LHCSR1) is the ics and use fluorescence lifetime information (11, 12). -
Comparison of Responses of Tattoos to Picosecond and Nanosecond Q-Switched Neodymium:YAG Lasers
STUDY Comparison of Responses of Tattoos to Picosecond and Nanosecond Q-Switched Neodymium:YAG Lasers CDR E. Victor Ross, USN; George Naseef, MD; Charles Lin, PhD; Michael Kelly, MS; Norm Michaud, MS; Thomas J. Flotte, MD; Jill Raythen; R. Rox Anderson, MD Objective: To test the hypothesis that picosecond la- ated with the study (and blinded to the treatment type) ser pulses are more effective than nanosecond domain evaluated photographs to assess tattoo lightening. For- pulses in clearing of tattoos. malin-fixed specimens were examined for qualitative epi- dermal and dermal changes as well as depth of pigment Design: Intratattoo comparison trial of 2 laser treat- alteration. Electron micrographs were examined for par- ment modalities. ticle electron density and size changes (in vivo and in vitro). The gross in vitro optical density changes were Setting: A large interdisciplinary biomedical laser labo- measured. ratory on the campus of a tertiary medical center. Results: In 12 of 16 tattoos, there was significant light- Patients: Consecutive patients with black tattoos were ening in the picosecond-treated areas compared with enrolled; all 16 patients completed the study. those treated with nanosecond pulses. Mean depth of pigment alteration was greater for picosecond pulses, Intervention: We treated designated parts of the same but the difference was not significant. In vivo biopsy tattoo with 35-picosecond and 10-nanosecond pulses from specimens showed similar electron-lucent changes for 2 neodymium:YAG lasers. Patients received a total of 4 both pulse durations. In vitro results were similar for treatments at 4-week intervals. All laser pulse param- both pulse durations, showing increases in particle sizes eters were held constant except pulse duration. -
Picosecond Multi-Hole Transfer and Microsecond Charge- Separated States at the Perovskite Nanocrystal/Tetracene Interface
Electronic Supplementary Material (ESI) for Chemical Science. This journal is © The Royal Society of Chemistry 2019 Electronic Supplementary Information for: Picosecond Multi-Hole Transfer and Microsecond Charge- Separated States at the Perovskite Nanocrystal/Tetracene Interface Xiao Luo, a,† Guijie Liang, ab,† Junhui Wang,a Xue Liu,a and Kaifeng Wua* a State Key Laboratory of Molecular Reaction Dynamics, Dynamics Research Center for Energy and Environmental Materials, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China b Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices, Hubei University of Arts and Science, Xiangyang, Hubei 441053, China * Corresponding Author: [email protected] † Xiao Luo and Guijie Liang contributed equally to this work. Content list: Figures S1-S9 Sample preparations TA experiment set-ups Estimation of the number of attached TCA molecules per NC Estimation of FRET rate Estimation of average exciton number at each excitation density Estimation of exciton dissociation number S1 a 100 b long edge c short edge 70 7.90.1 nm 9.60.1 nm 60 80 50 s s 60 t t n 40 n u u o o C 30 C 40 20 20 10 0 0 4 6 8 10 12 14 16 18 2 4 6 8 10 12 Size (nm) Size (nm) Figure S1. (a) A representative transmission electron microscopy (TEM) image of CsPbBrxCl3-x perovskite NCs used in this study. Inset: high-resolution TEM. (b,c) Length distribution histograms of the NCs along the long (b) and short (c) edges. -
Tunable Temporal Gap Based on Simultaneous Fast and Slow Light in Electro-Optic Photonic Crystals
Tunable temporal gap based on simultaneous fast and slow light in electro-optic photonic crystals Guangzhen Li, Yuping Chen, ∗ Haowei Jiang, Yi'an Liu, Xiao Liu and Xianfeng Chen State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China ∗[email protected] Abstract: We demonstrated a tunable temporal gap based on simul- taneous fast and slow light in electro-optic photonic crystals. The light experiences an anomalous dispersion near the transmission center and a normal dispersion away from the center, where it can be accelerated and slowed down, respectively. We also obtained the switch between fast and slow light by adjusting the external electric filed. The observed largest temporal gap is 541 ps, which is crucial in practical event operation inside the gap. The results offer a new solution for temporal cloak. OCIS codes: (160.2100) Electro-optical materials; (160.4330) Nonlinear optical materials; (060.5060) Phase modulation; (230.3205) Invisibility cloaks. References and links 1. M. W. McCall, A. Favaro, P. Kinsler, and A. Boardman, “A spacetime cloak, or a history editor,” Journal of optics 13, 024003 (2011). 2. M. Fridman, A. Farsi, Y. Okawachi, and A. L. Gaeta, “Demonstration of temporal cloaking,” Nature 481, 62–65 (2012). 3. R. W. Boyd and Z. M. Shi, “Optical physics: How to hide in time,” Nature 481, 35–36 (2012). 4. K. D. Wu and G. P. Wang, “Design and demonstration of temporal cloaks with and without the time gap,” Opt. Express 21, 238–244 (2013). -
Attosecond Light Pulses and Attosecond Electron Dynamics Probed Using Angle-Resolved Photoelectron Spectroscopy
Attosecond Light Pulses and Attosecond Electron Dynamics Probed using Angle-Resolved Photoelectron Spectroscopy Cong Chen B.S., Nanjing University, 2010 M.S., University of Colorado Boulder, 2013 A thesis submitted to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirement for the degree of Doctor of Philosophy Department of Physics 2017 This thesis entitled: Attosecond Light Pulses and Attosecond Electron Dynamics Probed using Angle-Resolved Photoelectron Spectroscopy written by Cong Chen has been approved for the Department of Physics Prof. Margaret M. Murnane Prof. Henry C. Kapteyn Date The final copy of this thesis has been examined by the signatories, and we find that both the content and the form meet acceptable presentation standards of scholarly work in the above mentioned discipline. iii Chen, Cong (Ph.D., Physics) Attosecond Light Pulses and Attosecond Electron Dynamics Probed using Angle-Resolved Photoelectron Spectroscopy Thesis directed by Prof. Margaret M. Murnane Recent advances in the generation and control of attosecond light pulses have opened up new opportunities for the real-time observation of sub-femtosecond (1 fs = 10-15 s) electron dynamics in gases and solids. Combining attosecond light pulses with angle-resolved photoelectron spectroscopy (atto-ARPES) provides a powerful new technique to study the influence of material band structure on attosecond electron dynamics in materials. Electron dynamics that are only now accessible include the lifetime of far-above-bandgap excited electronic states, as well as fundamental electron interactions such as scattering and screening. In addition, the same atto-ARPES technique can also be used to measure the temporal structure of complex coherent light fields.