NIST Technicalendar March 3 to March 7, 2008 The NIST Technicalendar is issued each Friday. All items MUST be submitted electronically from this web page by 12:00 NOON each Wednesday unless otherwise stated in the NIST Technicalendar. The address for online weekly editions of the NIST Technicalendar and NIST Administrative Calendar is: http://www.nist.gov/tcal/.

In this Issue: Meetings at NIST Meetings Elsewhere Announcements Talks by NIST Personnel NIST Web Site Announcements NIST Administrative Calendar (current)   NIST Vacancy Announcements (current)

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10:30 AM - Quantum Electrical Metrology Division Seminar
10:30 AM - The Development of Surface Tension-Confined Microfluidic Platforms

8:30 AM - 7th Symposium on Identity and Trust on the Internet (IDtrust 2008)
10:30 AM - Silicon Spintronics
2:00 PM - Ultra-Flexible Electroluminescent Systems for Both Visible and Near-Infrared Emission

No Scheduled Events

9:15 AM - The Estimation of Spin-penetration Depth in Ferromagnetic Metals
10:30 AM - Biomimetic Nanoscience: Challenges and Opportunities
10:30 AM - Functionalized Graphene nano sheets (FGS) as a new material for polymer composites and barrier films
11:00 AM - Functionalized graphene nano-sheets as a new material for polymer composites
11:30 AM - Block Locally Optimal Preconditioned Eigenvalue Xolvers (BLOPEX) Software Package
1:30 PM - Recent Developments in the Scanning Probe Microscopy

10:30 AM - Energy Options: A Global Energy Perspective
1:30 PM - "Revealing Magnetic Interactions From Single-Atom Magnetization Curves"

3/3 -- MONDAY

10:30 AM - QUANTUM ELECTRICAL METROLOGY DIVISION SEMINAR: Quantum Electrical Metrology Division Seminar
National Physical Laboratory of India (NPL-I) is a premier scientific institute of India and is also a National Measurement Institute of the country and maintains the SI units. In the present talk some aspects about NPL and its activities will be covered in brief. In detail we would discuss the activities of electrical and electronics standards division. The talk will emphasize on the activities of JVS & DC Standards of NPL-India which maintains the DC voltage, DC current and DC resistance parameters and provide the traceability to the Indian industries and R&D institutes with uncertainties ranging from ? ± 0.08 ppm to ? ± 10,000 ppm.. We will also present about the realization of 1Volt and 10 Volt Josephson series array voltage standard and its dissemination in India. Further more we will also highlight about our experience about MRA (JVS & DC was the first Lab in NPL-India to have International Peer and CMC successfully added to BIPM Appendix 'C'). As a case study of DC measurement we will also highlight the role of calibration, intercomparison, metrological timeliness and factors that affect the periodicity of calibration in traceability. In the end future plan of the group will be highlighted namely realization of programmable Josephson voltage standard, extension of ranges of DC Volt, current, resistance etc in the nano ranges under the nanometrology programme of NPL.
Dr. Vijay Ojha , National Physical Laboratory - India, New Delhi, India.
Metrology (220) Bldg, Rm. B165. (NIST Contact: Yi-hua Tang, 301-975-4691, yi-hua.tang@nist.gov)

10:30 AM - POLYMERS DIVISION SEMINAR: The Development of Surface Tension-Confined Microfluidic Platforms
The field of microfluidics, lab-on-a-chip technologies in particular, promises the capacity to automate sophisticated laboratory analyses into a platform that can be implemented by a user with minimal analytical experience. However, the fabrication methods traditionally employed to manufacture microfluidic devices are cost ineffective and time intensive. Consequently, current production techniques render exploiting this technology for clinical application problematic. This lecture describes an alternative fabrication technique to mitigate the aforementioned problems through the two-dimensional patterning of surface energy discontinuities. Hydrophilic conduits are patterned on a variety of commodity polymeric substrates. The microfluidic platforms demonstrate the ability to facilitate spontaneous capillary pumping with a high degree of precision. In particular, a cost-effective fabrication procedure is illustrated as well as the capacity to manipulate fluids within the platforms utilizing volumes less than 20 total microliters. Furthermore, applications are demonstrated within the devices such as enzymatic-catalysis, on-chip glucose and albumin detection, and curvature-mediated passive mixing. Such results demonstrate the efficacy of the platform to automate fluid transport concomitantly with reaction processes. Consequently, commercialization opportunities for this mass production amenable microfluidic technology are under consideration.
Michael Swickrath , Graduate Student, Case Western Reserve University Department of Chemical Engineering, Cleveland, OH, mjs60@case.edu.
224 Bldg, Rm. A312. (NIST Contact: Michael Fasolka, 301-975-8526, michael.fasolka@nist.gov)


3/4 -- TUESDAY

8:30 AM - COMPUTER SECURITY DIVISION SEMINAR: 7th Symposium on Identity and Trust on the Internet (IDtrust 2008)
Previously known as the PKI R&D Workshop, our new name reflects interest in a broader set of tools and the goal of an identity layer for the Internet. We aim to get practitioners in different sectors together to apply the lessons of real-world deployments to the latest research and ideas on the horizon. Join with experts from NIST, FPKIPA, OASIS, private industry and universities throughout the world to discuss all aspects of identity and trust. Peer reviewed papers focused on Identity Management, Health Care, Public Key Infrastructure and Access Control in Open System will be combined with topical panels during the two and half day event. Two scheduled panels include the Liberty Alliance Identity Assurance Framework and Open Reputation Management Systems. As always, there will be plenty of opportunities for informal networking.

Administration Bldg, Red Auditorium. (NIST Contact: Sara Caswell, 301-975-4634, sara@nist.gov) http://middleware.internet2.edu/idtrust/2008/
Special Assistance Available (teresa.vicente@nist.gov)

10:30 AM - ATOMIC PHYSICS DIVISION SEMINAR: Silicon Spintronics
Despite Silicon's intrinsic advantages for spintronics, even the basic elements of spin transport had not been unambiguously achieved in this semiconductor until recently.[1] I will discuss the specific challenges associated with spin injection and detection in Silicon (Si), and our unique solution, employing ballistic hot-electron transport through nano-scale ferromagnetic metal spin "polarizers". Using this technique, we have observed unprecedented coherence in spin precession measurements, and extracted very long spin lifetimes of conduction electrons traveling over macroscopic distances.[2] Whereas transistor scaling limits will soon suppress progress in microelectronics using Si, spintronics may secure this semiconductor's dominance for the future. [1] Ian Appelbaum, B.Q. Huang, and D.J. Monsma, "Electronic measurement and control of spin transport in silicon," Nature 447, 295 (2007). [2] B.Q. Huang, D.J. Monsma, and Ian Appelbaum, "Coherent spin transport through a 350-micron-thick silicon wafer," Phys. Rev. Lett. 99, 177209 (2007).
Ian Appelbaum , Assistant Professor, Electrical and Computer Engineering, University of Delaware.
Physics Building, Room B145. (NIST Contact: Neil Zimmerman, 301-975-5887, neil.zimmerman@nist.gov)

2:00 PM - POLYMERS DIVISION SEMINAR: Ultra-Flexible Electroluminescent Systems for Both Visible and Near-Infrared Emission
Ambient screen printing processes were developed to produce both visible and near infrared (NIR) light emitting devices on flexible plastic and textile substrates. This unique electroluminescent (EL) technology provides an integrated illumination system for soft-walled, portable battlefield shelters such as the chemical biological protective shelters (CBPS). The ability to print light emitting structures on textiles allows for fabrication of lighting systems that bend and collapse along with the tent structure, reducing deployment time and enhancing logistics. Extending emission wavelengths to the near infrared (NIR) region allowed for the development of flexible, covert illumination and backlighting technology, such that a NIR map-reader prototype readable only with NIR night vision equipment could be fabricated. Commercially available lighting systems are based on sealed glass bulbs filled with inert gases or filaments (fluorescent or incandescent lamps) or on arrays of discrete solid state LEDs (light emitting diodes). Over the past decade, researchers have been striving to replace LEDs with OLEDs (organic light emitting devices) or PLEDs (polymer light emitting devices) because they are more easily processed and can be fabricated into flexible displays. Although several major companies are on the verge of launching flexible display products, the manufacturing processes still often require vacuum deposition steps for organic molecules, at least case when small organic molecule emitters are employed, and for low work function metals for electron injection into the organic semiconductor. Since low work function metals such as Mg, Al and Ca are susceptible to environmental corrosion, the devices must be encapsulated to keep out moisture and oxygen, which is a tedious and often highly inefficient process. The processing and ambient stability issues of OLED and PLED technologies prohibit their application on textile, fabric or plastic substrates that are permeable to moisture or oxygen. To fulfill the unmet need of highly flexible and environmentally stable lighting on a variety of substrates, Crosslink has utilized the unique properties of electroactive or conductive polymer systems to develop a fully ambient screen printing process for the fabrication of ultraflexible, large area, electroluminescent light (EL) emitting panels for both visible (VIS) and near infrared (NIR) light. This presentation will describe the basic flexible EL system technology and applications including: 1.The functional printable coating systems employing intrinsically conductive polymers (ICPs) and electroluminescent (EL) materials 2.Basic flexible EL system construction, process, capabilities and performance 3.Hybrid systems utilizing photoluminescent (PL) materials including LEPs 4.Broad and narrow band Near Infrared (NIR) emission 5.Applications in portable shelter lighting and covert map reading
Pat Kinlen , CTO / Crosslink USA.
224 Bldg, Rm. A312. (NIST Contact: Dean DeLongchamp, 301-975-5599, deand@nist.gov)


3/5 -- WEDNESDAY

No Scheduled Events

3/6 -- THURSDAY

9:15 AM - CNST ELECTRON PHYSICS GROUP SEMINAR: The Estimation of Spin-penetration Depth in Ferromagnetic Metals
In the development of spintronics device like a MRAM, the spin-current-induced magnetic reversal is important, because it is expected to reduce the power consumption of device. The penetration depth of transverse component of spin-current is the distance the induced spin relax in ferromagnetic metals and it influence the behavior of spin-current-induced magnetic reversal. In this work, we report the experimental determination of the spin-penetration depth.
Satoshi Yakata , Dr. - Tohoku University, Sendai, yakata2@mlab.apph.tohoku.ac.jp.
217 Bldg, Rm. H107. (NIST Contact: Robert McMichael, 301-975-5121, robert.mcmichael@nist.gov)

10:30 AM - CNST NANOTECHNOLOGY SEMINAR SERIES: Biomimetic Nanoscience: Challenges and Opportunities
The adaptive pressures displayed across the flora and fauna result in a variety of sophisticated nanostructured materials that are perfected to perform multiple biological functions. Our understanding of the underlying principles of their formation provides ample opportunities in the synthesis of next generation, bio-inspired, nanostructured materials. To date, there has been demonstrable progress in materials fabrication harnessing the functional power of biological systems. There is, however, a number of challenges related to the characterization of both biological and synthetic bio-related structures. I will exemplify this point by describing new synthetic strategies and devices that have been inspired by the study of two organisms – echinoderms and sponges. The topics will include self-assembly, control of crystallization, adaptive optical structures, fiber-optics, biomechanics, hybrid materials and novel actuation systems.
Joanna Aizenberg , Professor - Harvard University.
215 Bldg, Rm. C103 - C106. (NIST Contact: Nikolai Zhitenev, 301-975-6039, nikolai.zhitenev@nist.gov)

10:30 AM - POLYMERS DIVISION SEMINAR: Functionalized Graphene nano sheets (FGS) as a new material for polymer composites and barrier films
There has been considerable interest and activity in the area of nanoparticle-filled polymer composites because of the predicted enhancement in mechanical, electrical, and transport properties. Carbon nano tubes and clay nano sheets have been the most widely studied materials, but each has significant limitations. We present a new nanofiller based on completely exfoliated graphite sheets. The electrically conductive sheets show a percolation threshold between 1-2 wt% when incorporated into a polymethylmethacrylate (PMMA) matrix. This is in contrast to 7.5 wt% loading of conductive carbon black that must be added to obtain conductivity. The elastic modulus versus temperature for a graphene-filled PMMA composite shows an increase in modulus with filler loading. But most significantly, the addition of 0.25 wt% graphene increases the glass transition temperature from 95 C to 118 C. The graphene filler shows reinforcement of elastomers at loadings of 1% that are comparable to reinforcement with 20% carbon black. Synchotron scattering during deformation shows a dramatic change in the crystallization behavior of natural rubber when filled with graphene. The fillers decrease gas permeation 2 to 10 times more effectively than clay nano sheets.
Robert Prud'homme , Professor - Department of Chemical Engineering, Princeton University, Princeton, NJ, prudhomm@princeton.edu.
224 Bldg, Rm. A312. (NIST Contact: Jan Obrzut, 301-975-6845, jan.obrzut@nist.gov)

11:00 AM - POLYMERS DIVISION SEMINAR: Functionalized graphene nano-sheets as a new material for polymer composites
There has been considerable interest and activity in the area of nanoparticle-filled polymer composites because of the predicted enhancement in mechanical, electrical, and transport properties. Carbon nano tubes and clay nano sheets have been the most widely studied materials, but each has significant limitations. We present a new nanofiller based on completely exfoliated graphite sheets. The electrically conductive sheets show a percolation threshold between 1-2 wt% when incorporated into a polymethylmethacrylate (PMMA) matrix. This is in contrast to 7.5 wt% loading of conductive carbon black that must be added to obtain conductivity. The elastic modulus versus temperature for a graphene-filled PMMA composite shows an increase in modulus with filler loading. But most significantly, the addition of 0.25 wt% graphene increases the glass transition temperature from 95 C to 118 C. The graphene filler shows reinforcement of elastomers at loadings of 1% that are comparable to reinforcement with 20% carbon black. Synchotron scattering during deformation shows a dramatic change in the crystallization behavior of natural rubber when filled with graphene. The fillers decrease gas permeation 2 to 10 times more effectively than clay nano sheets when incorporated into natural rubber or thermoplastic elastomers.
Robert Prud'homme , Professor, Department of Chemical Engineering, Princeton University, Princeton, NJ, prudhomm@princeton.edu.
224 Bldg, Rm. A312 CR. (NIST Contact: Jan Obrzut, 301-975-6845, jan.obrzut@nist.gov)

11:30 AM - MATHEMATICAL AND COMPUTATIONAL SCIENCES DIVISION SEMINAR: Block Locally Optimal Preconditioned Eigenvalue Xolvers (BLOPEX) Software Package
Andrew Knyazev , University of Colorado - Denver.
Administration Bldg, Lecture Rm. D. (NIST Contact: William Mitchell, 301-975-3808, william.mitchell@nist.gov) http://math.nist.gov/mcsd/Seminars/2008/2008-03-06-Knyazev.html

1:30 PM - MATERIALS AND CONSTRUCTION RESEARCH DIVISION SEMINAR: Recent Developments in the Scanning Probe Microscopy
Nanotechnology encompasses science and engineering in many technical disciplines and industries, from material science to biotechnology and everywhere in between. The need to study and characterize phenomenon at a nano scale presents significant challenges. In many cases, a combination of complementary techniques is required to study and validate the results. Nanounity provides innovative solutions to characterize, develop, monitor and control critical processes for science and industry. Our goal is to deliver synergistic techniques that are complementary to the day-in and day-out research needs for nanotechnology. Nanounity represents and distributes a number of technical solutions: SPM technology, advanced SPM probes and sensors, nano-tensile testing, digital image correlation for deformation analysis and unique nano position stage technology. John Janzer of Nanounity and Ami Chand, Ph.D. of Appnano, will present information on new advancements in SPM probe technology and AFM/Raman spectroscopy. Dr. Chand, President of Appnano, will speak about Appnano's conventional and advanced probe technology. He will specifically discuss their new product the Hydra series probes, which is a probe made of a unique combination of Silicon and Silicon Nitride. The probe's features provide technical advances in both ambient and liquid image. The benefits of this technology will be discussed his presentation. John Janzer, Vice President of Sales for Nanounity will present material on AFM/Raman spectroscopy. He will present insight and updates in the areas of AFM/Raman spectroscopy, in-situ nano tensile testing on AFM and digital image correlation for nano-scale deformation analysis.
Ami Chand , President, Appnano. John Janzer , Vice President, Nanounity.
226 Bldg, Rm. B221. (NIST Contact: Xiaohong Gu, 301-975-6523, xiaohong.gu@nist.gov)


3/7 -- FRIDAY

10:30 AM - NIST COLLOQUIUM SERIES: Energy Options: A Global Energy Perspective
This presentation evaluates the technical, political, and economic challenges involved with widespread adoption of renewable energy technologies. Topics include: the available fossil fuel resources and reserves and the remaining years of supply; a comparison of their economics with those of renewable energy technologies; greenhouse gas buildup limitations on carbon-based power consumption; the level and timescale of R&D investment needed to support the expected global energy demand; the potential of renewable energy resources to support the projected global carbon-free energy demand; and the challenges to the chemical sciences to enable the cost-effective production of carbon-free power on the needed time scale.
Nathan Lewis , Division of Chemistry and Chemical Engineering, California Institute of Technology.
Administration Building, Red Auditorium. (NIST Contact: Kum Ham, 301-975-4203, kham@nist.gov)
Special Assistance Available

1:30 PM - CNST ELECTRON PHYSICS GROUP SEMINAR: "Revealing Magnetic Interactions From Single-Atom Magnetization Curves"
The ongoing miniaturization of magnetic devices towards the limit of single atoms calls for appropriate tools to study their magnetic properties. We demonstrate the ability to detect magnetization curves of individual magnetic atoms adsorbed on a metallic substrate using a scanning tunneling microscope with a spin-polarized tip. This enables to map tiny magnetic interactions on the atomic length scale which is evidenced by measuring the RKKY-like indirect exchange between a cobalt adatom and a cobalt nanowire on platinum(111). The method allows for future application to magnetic defects in semiconductors, in order to improve our understanding of diluted magnetic semiconductors. As a first step we will show our detailed investigation of the electronic structure of Mn acceptors in InAs.
Jens Wiebe , Dr./Scientific Staff - University of Hamburg, , jwiebe@physnet.uni-hamburg.de.
217 Bldg, Rm. H107. (NIST Contact: Joseph Stroscio, 301-975-3716, joseph.stroscio@nist.gov)


ADVANCE NOTICE

3/10/08 2:00 PM - STANDARDS SERVICES DIVISION SEMINAR: Overview of the ANSI Intellectual Property Policy
This seminar will cover issues relating to ANSI policies covering the use of essential patents or other proprietary intellectual property in standards implemented by ANSI accredited Standard Developing Organizations. An initial overview will be provided by Mr. Dan Bart, the Chair of the ANSI Intellectual Property Rights Committee, followed by a panel discussion featuring Mr. Bart, George Arnold, and Mike Rubin responding to questions from the audience.
Mr. Dan Bart , Chair of the ANSI Intellectual Property Rights Committee.
Administration Bldg, Employees Lounge. (NIST Contact: Erik Puskar, 301-975-8619, erik.puskar@nist.gov)

3/11/08 10:30 AM - ATOMIC PHYSICS DIVISION SEMINAR: Laser Cooling for Nanotechnology
Laser cooling and the associated light-atom manipulation techniques have much to offer the world of nanotechnology. I will discuss ongoing projects in the CNST where these tools are put to use to develop novel approaches to nanoscale measurement problems. Recent results on generation of a MOT-based, high-brightness, low-emittance ion beam for focused ion beam applications will be discussed, including how this can be used to deterministically implant single atoms one at a time, realize a helium-ion microscope, or perform gallium-free ion milling. Results in trapping of erbium at microkelvin temperatures will also be discussed as an example of the expansion of cooling techniques to atoms of practical interest. In the case of erbium, the motivation lies in its atom-like optical properties when implanted in a material, which suggest its use as a nanoscale sensor. In trapping erbium, we have found it to exhibit some interesting new trap phenomena, such as trapping without repumping, MOT formation with a single, blue-detuned laser beam, and other unusual effects that occur in the regime where optical, magnetic, and gravitational forces are all of the same magnitude.
Jabez McClelland, Group Leader , Electron Physics Group, Center for Nanoscale Science and Technology, NIST.
Building 221, Rm. B145. (NIST Contact: Mary Talbot, 301-975-3206, mary.talbot@nist.gov)

3/14/08 10:30 AM - NIST COLLOQUIUM SERIES: The Measure of All Things: The Seven Year Odyssey That Changed the World
In June 1792, in the midst of the French Revolution, two astronomers set out from Paris on a mission to measure the size of the world. Their goal was to establish a universal standard equal to one ten-millionth of the distance from the north pole to the equator--a unit to be known as the meter. After 7 years they returned to a hero's welcome. "Conquests will come and go," Napoleon proclaimed, "but this work shall endure." In the past 200 years the meter has become the measure of the world. Yet all this time a secret "error" has been incorporated into the determination of the meter--an error known only to the two astronomers and hidden by them from public view. This history of their expedition will examine the origin of error analysis, the rise of modern geodesy, and history's first debate over globalization. Copies of the award-winning book, The Measure of All Things, will be available for review and purchase at the talk.
Ken Alder , Department of History, Northwestern University.
Administration Building, Red Auditorium. (NIST Contact: Kum Ham, 301-975-4203, kham@nist.gov)
Special Assistance Available

3/19/08 8:00 AM - POLYMERS DIVISION SEMINAR: Workshop on the Directed Assembly of Functional Materials and Devices
Controlling the placement of nanoscale units into designed structures and patterns through directed assembly processes answers one of the grand challenges of nanotechnology. Innovative approaches using the directed assembly of nanoscale units are being developed to facilitate the nanofabrication of new materials and applications that can incorporate biological functionality, or devices such as flexible, large-area electronics devices. Directed assembly methods provide an opportunity to overcome limitations of traditional semiconductor processing; specifically, the small materials set with which to work, restriction to two dimensional patterning, and exorbitant equipment costs. Moving directed assembly from research demonstrations to viable manufacturing processes is difficult because it requires control over the simultaneous transport, placement, and interactions of a potentially large set of nanoscale units with different size, shape, and chemical functionality. New measurements and process control methods must be developed to enable successful implementation of this groundbreaking technology. This workshop will bring together leading researchers and stakeholders from industry, government, and academia that are actively engaged in research and development of the directed assembly of nanoparticles into functional materials and devices. Through invited presentations and focused discussions, the workshop will explore and identify the most pressing measurement and technological needs to advance directed assembly as a viable manufacturing method for future nanotechnology applications.
Heiko Wolf , International Business Machines,. Haw Yang, Christopher Murray, Oleg Gang, Babak Parviz, Dan Herr, Mike Natan, Mike Bevan, Abe Stroock, Sharon Glotzer, Kate Stebe, Chong Ahn, CJ Kim, Hiroshi Matsui, Alex Tkachenko
AML, 215 Bldg, Rm. C103/106. (NIST Contact: Steven Hudson, 301-975-6579, steven.hudson@nist.gov) http://polymers.nist.gov/Directed_Assembly/Directed_Assembly_Workshop2.htm
Rooms are wheel chair accessible.

3/19/08 1:30 PM - CNST ELECTRON PHYSICS GROUP SEMINAR: Imaging of screened potential and superconductivity in nanoscale spatial resolution by low-temperature STM/S
By using scanning tunneling microscopy (STM), we can make images of various physical properties in nanometer-scale spatial resolutions. Here, I demonstrate imaging of electrostatic potential and superconductivity by STM. The electrostatic potential around a charge is described with the Coulomb potential. If the charge is located in a metal, the potential is modified because of the electrons in the host. The potential modification, called screening, is one of the fundamental phenomena in the condensed matter physics. Using low-temperature STM we have developed a method to measure electrostatic potential in high spatial and energy resolutions, and observed the potential around external charges screened by two-dimensional surface electronic states. Characteristic potential decay and the Friedel oscillation were clearly observed around the charges. Superconductivity of nano-size materials, whose dimensions are comparable with the coherent length, is quite different from their bulk. We investigated superconductivity of ultra thin Pb islands by directly measuring the superconducting gaps using STM. The obtained tunneling spectra exhibit a variation of zero bias conductance (ZBC) with a magnetic field, and spatial mappings of ZBC revealed the vortex formation. Details of the imagings will be discussed at the presentation.
Yukio Hasegawa , Dr./Associate Professor/The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Japan, hasegawa@issp.u-tokyo.ac.jp.
Bldg. 217, Rm. H107. (NIST Contact: Joseph Stroscio, 301-975-3716, joseph.stroscio@nist.gov)

3/24/08 10:30 AM - CNST ELECTRON PHYSICS GROUP SEMINAR: Slow-moving atoms and fast-moving particles: Recent results in erbium laser cooling and particle-tracking microscopy
In this talk, I will present the latest results from two research projects in CNST. In the first part, I will discuss new methods for bringing erbium atoms to ultracold temperatures by exploiting the unique laser-cooling properties of this strongly magnetic rare-earth element. The capability to cool, trap and manipulate erbium has applications for developing nanoscale optical devices and may provide access to new regimes in the study of magnetically interacting quantum gases. In the second part, I will discuss a recent breakthrough in tracking the motion of freely diffusing (solution-phase) particles using optical microscopy. A major stumbling block in achieving real-time control of individual molecules or nanoparticles is the difficulty of quickly and accurately extracting accurate position information from a CCD image. We recently developed a new computational method for extracting such information, capable of localizing particles to a few nanometers through a fast and flexible algorithm.
Andrew Berglund , Dr./Physicist., Center for Nanoscale Science and Technology, andrew.berglund@nist.gov.
Bldg.217, Rm. H107. (NIST Contact: Jabez McClelland, 301-975-3721, jabez.mcclelland@nist.gov)

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MEETINGS ELSEWHERE


3/3 -- MONDAY

No Scheduled Events

3/4 -- TUESDAY

2:30 PM - ENZYMATIC SYMMETRY BREAKING: HOW DOES TOPOISOMERASE IV DISTINGUISH LEFT FROM RIGHT?
Topoisomerases are essential enzymes that perform the crucial task of maintaining DNA topology and unlinking catenated or knotted DNA. Topoisomerase IV (Topo IV) is a bacterial topoisomerase that transports one segment of DNA through a transient double-strand break in a second segment of DNA. In contrast with topoisomerases from higher organisms, Topo IV demonstrates remarkable selectivity in its strand passage activity. The crossings formed in over-wound DNA (left-handed supercoils) are relaxed faster by Topo IV than those formed in under-wound DNA (right-handed supercoils). How can an enzyme that acts locally distinguish the global topological state of DNA? What mechanisms underlie the asymmetric relaxation of left- versus right-handed supercoils by Topo IV? To address these questions, we developed a magnetic-tweezers based single-DNA crossing unlinking assay. This assay allows us to measure, in real time, individual strand passage events by Topo IV. In conjunction with Monte Carlo simulations of individual DNA crossings, these measurements permit determination of the preferred DNA crossing angle for Topo IV. Surprisingly, the preferred crossing angle is significantly larger than previous estimates and can not account for the difference in relaxation rates of left- and right-handed supercoiled DNA. Rather, our results demonstrate that symmetry breaking by Topo IV is achieved through an unusual processivity mechanism.
Keir Neuman , National Heart, Lung, and Blood Institute, NIH,.
Bldg, Rm..
CARB II, Room 2129. (NIST Contact: Kimberly Briggman, 301-975-2358, kbriggma@nist.gov)



3/5 -- WEDNESDAY

No Scheduled Events

3/6 -- THURSDAY

No Scheduled Events

3/7 -- FRIDAY

No Scheduled Events

ADVANCE NOTICE

No Scheduled Events

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TALKS BY NIST PERSONNEL

RALCHENKO, Y. : DECIPHERING LINE SPECTRA FROM HIGHLY-CHARGED IONS.
IAEA Workshop on Challenges in Plasma Spectroscopy in Future Fusion Reactors, Jaipur, India, 2/20.

DOUGHERTY, D. : ELECTRONIC PROPERTIES OF MOLECULAR ASSEMBLIES ON SURFACES: THE ROLE OF LOCAL ENVIRONMENT.
University of Massachusetts, Physics Department, Amherst, MA, 3/3.

SCOTT, K. : 3D CHEMICAL MAPPING OF NANOPARTICLES IN CELLS.
nanoECO 2008, Nanoparticles in the Environment - Implications and Applications, Centro Stefano Franscini, Monte Verita, Ascona, Switzerland, 3/4.

SOLES, C. : THE DIRECT PATTERNING OF ORGANOSILICATE MATERIALS BY NANOIMPRINT LITHOGRAPHY.
SPIE Advanced Lithography Conference, Ventura, CA, 3/4.

BREWER, T. : INVESTIGATION OF VARIOUS DOPANT MATERIALS FOR INCREASED SPECIFICITY OF EXPLOSIVES IN ION MOBILITY SPECTROMETRY (IMS).
Pittcon 2008 Conference, New Orleans, LA, 3/5.

KARIM, A. : APPLICATION OF GRADIENTS-I.
American Physical Society Short Course, New Orleans, LA, 3/8.

RICHTER, L. : THERMAL, STRUCTURAL, AND ELECTRICAL CHARACTERIZATION OF TWO HIGH PERFORMANCE SEMICONDUCTING POLYMERS.
American Physical Society March Meeting, Ernest N. Murial Convention Center, New Orleans, LA, 3/10.

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ANNOUNCEMENTS

5TH NIST POLYMER MASS SPECTROMETRY WORKSHOP
This workshop will bring together researchers and practitioners to present new results, discuss recent trends, and identify important problems in the mass spectrometry of synthetic macromolecules and engineered nanoparticles. The Workshop schedule includes invited hour-long talks by internationally recognized leaders in their respective fields, a poster session, and a problem solving session where workshop participants will be asked to present measurement problems they have encountered in their own work for comment and discussion by other workshop participants.
NIST Contact: William E. Wallace, 301-975-5886, william.wallace@nist.gov

NIST LEADERSHIP DEVELOPMENT PROGRAM ANNOUNCEMENT
The NIST Leadership & Employee Development Program (LED) will launch Class V of the Building the Next Generation Program (BTNG) on April 28, and Class VII of the New Leader Program (NLP) on June 23. New Leader Program (NLP) NLP: The NLP is a one-year program designed to provide new leaders with the necessary knowledge and skills to be successful in leadership positions at NIST. The program designed for individuals who have served in a leadership positions (e.g., group leader, project leader, program manager) for three years or less, and/or who have had little leadership training. The NLP consist of a 360-degree assessment, the weeklong New Leader Course, monthly cohort meetings, leadership coaching, and a capstone project. Building the Next Generation Program BTNG: The BTNG is a yearlong program dedicated to developing leadership competencies and preparing individuals to move into leadership positions at NIST. The BTNG consists of a one-week fundamental leadership course, 360-degree assessment, and monthly seminars. The BTNG also includes several elective options: mentoring, developmental assignments, special study group, and "in lieu of course(s)" option. See the Administrative Calendar for details on registration, informational briefings, and dates for the weeklong courses that kick-off both programs. Questions? Please call Mike Martin, x3890.
NIST Contact: Mike Martin, 301-975-3890, michael.martin@nist.gov

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NIST WEB SITE ANNOUNCEMENTS

No Web Site announcements this week.

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For more information, contact Ms. Sharon Hallman, Editor, Stop 2500, National Institute of Standards and Technology, Gaithersburg MD 20899-2500; Telephone: 301-975-TCAL (3570); Fax: 301-926-4431; or Email: tcal@nist.gov.

All lectures and meetings are open unless otherwise stated.

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