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Sample records for 2007-2008 international polar

  1. WMO Role In The International Polar Year 2007-2008

    NASA Astrophysics Data System (ADS)

    Sarukhanian, E.

    2004-12-01

    The Fourteenth World Meteorological Congress in May 2003 had approved the idea of holding an International Polar Year in 2007-2008. The ICSU Executive Board in February 2004 decided to establish an IPY in 2007-2008 and invited WMO to jointly sponsor the IPY. In June 2004, ICSU and WMO agreed to act as cosponsors for the IPY. WMO contributions to the IPY would be focused on the areas of activities that are closely related to five themes of IPY Science Plan. One of the most important areas is the enhancement of observing components in Polar Regions. It includes re-activation of existing or establishing of new meteorological stations, increase the number of drifting buoys, ships and aircraft in Polar Regions. The existing satellites and new operational satellites with observational capabilities for Polar Regions will be used. In the atmospheric research area WMO plans to enhance integrated monitoring of the ozone layer, using ground-based optical remote sensing instrumentation and ozone sondes aircraft and satellites. It is also planned to intensify integrated measurement and modelling of the transport of greenhouse gases and aerosols. The period of IPY will overlap with the timeframe of Global Atmosphere Research Programme /(THORPEX/) carried out by WMO. Its implementation in Polar Regions is considered as part of IPY that would increase knowledge of global to regional influences on the initiation, evolution and predictability of high-impact weather, and contribute to the design and demonstration of interactive forecast system that allow information to flow between users, numerical modellers, data assimilation system and observations to maximize forecast skill and enhance the utility of forecasts. In the area of climate assessment WMO is intended to participate in the development of an IPY data management plan and coordinate establishment of a database of historical polar climate and related data, investigate teleconnections between polar regions and the lower

  2. International Polar Year 2007/2008 - snapshots from Space

    NASA Astrophysics Data System (ADS)

    Jezek, K.

    2003-04-01

    Satellite observations are revolutionizing our ability to observe the poles and polar processes. No other technology developed since the IGY of 1957 provides the high-resolution, continental-scale, frequent-repeat, and all-weather observations available from spaceborne sensors. The utility of that technology is evidenced by associated scientific advances including measurements of long term trends in polar sea ice cover and extent, the realization that the polar ice sheets can change dramatically at decade or less time scales, and the quantification of relationships between processes at the poles and at mid and equatorial latitudes. There are many examples of successful spaceborne observations from pole to pole for scientific, commercial and governmental purposes. These successes encourage the use of the capabilities and consequently, the competition for access to resources from the international constellation of satellites becomes increasingly more intense. Frequently, this means that there are only limited opportunities for conducting large-scale projects that consume a significant fraction of system capabilities for some dedicated period of time. An example of a large-scale coordinated effort is the Radarsat Antarctic Mapping Project that required months of dedicated satellite and ground support time to achieve its objective of obtaining near instantaneous 'snapshots' of Antarctica to serve as gauges for measuring future changes. Large-scale coordinated-experiments will continue to be important for polar scientists seeking to understand the role of polar processes in climate change. These future missions will be further enhanced if complementary observations and data analysis from different satellite sensors can be coordinated (for example IceSAT laser altimeter observations of ice sheet surface topography with EnviSAT SAR observation of ice sheet motion). That coordination is challenging in part because of resource allocation issues and in part because space

  3. International Polar Year 2007/2008 - A Snapshot from Space

    NASA Astrophysics Data System (ADS)

    Noltimier, K.; Jezek, K.; Box, J.

    2002-12-01

    Satellite observations are revolutionizing our ability to observe the poles and polar processes. No other technology developed since the IGY of 1957 provides the high-resolution, continental-scale, frequent-repeat, and all-weather observations available from spaceborne sensors. The utility of that technology is evidenced by associated scientific advances including measurements of long term trends in polar sea ice cover and extent, the realization that the polar ice sheets can change dramatically at decade or less time scales, and the quantification of relationships between processes at the poles and at mid and equatorial latitudes. There are many examples of successful spaceborne observations from pole to pole for scientific, commercial and governmental purposes. These successes encourage the use of the capabilities and consequently, the competition for access to resources from the international constellation of satellites becomes increasingly more intense. Frequently, this means that there are only limited opportunities for conducting large-scale projects that consume a significant fraction of system capabilities for some dedicated period of time. An example of a large-scale coordinated effort is the Radarsat Antarctic Mapping Project that required months of dedicated satellite and ground support time to achieve its objective of obtaining near instantaneous 'snapshots' of Antarctica to serve as gauges for measuring future changes. Large-scale coordinated-experiments will continue to be important for polar scientists seeking to understand the role of polar processes in climate change. These future missions will be further enhanced if complementary observations and data analysis from different satellite sensors can be coordinated (for example IceSAT laser altimeter observations of ice sheet surface topography with EnviSAT SAR observation of ice sheet motion). That coordination is challenging in part because of resource allocation issues and in part because space

  4. The International Polar Year 2007-2008: a Preliminary Overview of Proposed Research Activities.

    NASA Astrophysics Data System (ADS)

    Allison, I.; Beland, M.; Members, J.

    2005-05-01

    The International Polar Year 2007-2008 (IPY 2007-2008), co-sponsored by the International Council for Science and the World Meteorological Organization, will be an intensive and internationally coordinated campaign of high quality research and observations in the polar regions. It will have an interdisciplinary emphasis, with active inclusion of the social sciences as well as natural science. The IPY 2007-2008 is intended to lay the foundation for major scientific advances in knowledge and understanding of the polar regions and their role in the functioning of the planet. IPY 2007-2008 will address six broad research themes. These are the present environmental status of the polar regions; change in the polar regions; the links and interactions between polar regions and the rest of the globe; frontiers of science in the polar regions; the polar regions as a unique vantage point to observe processes from the interior of the Earth, to the Sun and the cosmos beyond; and the culture, history, and sociology of human societies in polar regions. Details of the IPY science plan and its implementation are available in the IPY Framework document at www.ipy.org, A large number of proposals for potential IPY activities were received in January 2005 in response to a preliminary call for "Expressions of Intent". Those projects meeting the IPY criteria have been identified and are presently being developed more fully and, where appropriate, consolidated into larger projects. This presentation will provide an outline of the major scientific initiatives that are developing under the IPY 2007-2008 vision. Opportunities for participation in the developing IPY projects will be noted, as will those projects seeking additional input from new collaborators.

  5. A New Phase of Exploration and Understanding: Planning for The International Polar Year - 2007/2008

    NASA Astrophysics Data System (ADS)

    Bell, R. E.; Rapley, C.; Elfring, C.; Allison, I.; Bindschadler, R.; Chown, S.; Duhaime, G.; Kotlyakov, V.; Orheim, O.; Zhang, Z.; Kuhn, M.; Schalke, H.; Pandey, P.; Petersen, H. K.; Casassa, G.

    2003-12-01

    Planning is underway to hold an International Polar Year in 2007-2008. IPY 2007-2008 stands to be a significant research opportunity to further our understanding of polar regions and polar processes. The International Polar Year has the potential to capture the public's imagination and convey the crucial role that the polar regions play in global systems. IPY 2007-2008 is envisioned to be an intense, international campaign of coordinated polar observations and analysis, which will be bipolar in focus, multidisciplinary in scope, and truly international in participation. The vision is for many nations to work together to gain holistic insights into planetary processes, targeted at exploring and increasing our understanding of the poles and their roles in the global system. The concept of an International Polar Year 2007 - 2008 has been endorsed and advanced by a broad range of global and polar research groups. Earlier this year, the International Council for Science (ICSU) formed an International Polar Year Planning Group (IPY-PG) which met for the first time at the end of July. The Planning Group discussed ways to create an open process that encourages broad input from the international community. The Planning Group began to describe the desired goals of IPY 2007-2008, which should address compelling science issues through multi-national programs, enable scientific programs which would not otherwise occur, attract and develop the next generation of polar scientists, and engage the public. The Planning Group has identified three overarching themes that we hope can serve as the foundation for IPY 2007-2008: Exploring the Earth's Icy Domains, Decoding the Role of the Poles in Global Change Understanding Polar Processes. The Planning Group envisions focused research activities under each of these major themes. For example, a program to explore the sub-ice environment of East Antarctica would fit under the theme Exploring the Earth's Icy Domains, a program of Integrated

  6. Science Communication during the International Polar Year 2007-2008: Successes and Recommendations (Invited)

    NASA Astrophysics Data System (ADS)

    Carlson, D. J.; Ipy Education, Outreach; Communication Committee

    2010-12-01

    This IPY (International Polar Year 2007-2008) represented one of the largest international scientific research efforts ever undertaken. It stimulated the active engagement of thousands of teachers, students, and citizens around the globe through international collaboration and cooperation, careful cultivation of a global community of enthusiastic professional science communicators and educators, and creative use of free technologies. From music performances in Alaska to tree planting in Malaysia, hundreds of events and activities around the world demonstrated the public enthusiasm and the broad impact of IPY. This paper describes the core concepts and tangible activities developed and implemented by the IPY international Education, Outreach, and Communication (EOC) Committee and community and the International Programme Office (IPO) between March 2006 and December 2009. We present methods and accomplishments and address two questions: 1) How did these activities come about? 2) How do the ideas, tools, experiences, and successes from this IPY apply more broadly to science communication?

  7. A New Phase of Exploration and Understanding: Planning for The International Polar Year - 2007/2008

    NASA Astrophysics Data System (ADS)

    Rapley, C.; Bell, R.

    2004-05-01

    Planning is underway for an International Polar Year in 2007-2008. (IPY 2007/8) which will be a significant research opportunity to further our understanding of polar regions and polar processes. The International Polar Year has the potential to capture the public's imagination and convey the crucial role that the polar regions play in global systems. IPY 2007/8 will be an international programme of coordinated, interdisciplinary, scientific research in the Earth's polar regions to explore new frontiers, to increase our ability to detect changes at the Earth's poles and to deepen our understanding of polar processes and their global linkages. A crucial component of the IPY 2007/8 will be to attract and develop the next generation of polar scientists, engineers and leaders and to capture the interest of the public and decision-makers. The vision is for many nations to work together to gain holistic insights into planetary processes, targeted at exploring and increasing our understanding of the poles and their role in the global system. The concept of an International Polar Year 2007/8 has been endorsed and advanced by a broad range of global and polar research groups both internationally and nationally. To date 18 nations have formed national committees who are coordinating IPY activities nationally. The International Council for Science (ICSU) formed an International Polar Year Planning Group (IPY-PG) to stimulate, encourage and organize a debate on the International Polar Year 2007/8, formulate a set of objectives and develop a high level Science Plan. The Planning Group has sought input from the international science community and to date has received 138 ideas from over 22 nations. This input from the international community covers both poles, global processes and a diverse spectrum of disciplines. To date the input from the science community has identified key questions and proposed projects within the three major themes proposed by the ICSU IPY Planning Group

  8. Enhancing the Environmental Legacy of the International Polar Year 2007- 2008

    NASA Astrophysics Data System (ADS)

    Tin, T.; Roura, R.; Perrault, M.

    2006-12-01

    The International Geophysical Year (IGY) left a legacy of peace and international cooperation in the form of the 1959 Antarctic Treaty. Since the IGY, the 1991 Protocol of Environmental Protection to the Antarctic Treaty was signed and entered into force. The Protocol establishes that the protection of the environment and the wilderness values of Antarctica "shall be fundamental considerations in the planning and conduct of all activities in the Antarctic Treaty area". Fifty years on, the IPY 2007-08 can, in turn, leave behind a positive environmental legacy - where the sharing of facilities and logistics are encouraged, the human footprint in Antarctica is minimized and a future generation of environmentally aware scientists, logisticians and visitors is fostered. Based on an analysis of all Expressions of Interest submitted to the IPY, we found that about three-quarters of IPY's Antarctic projects plan to have fieldwork components. About one-third of these field projects expect to leave physical infrastructure in Antarctica. A number of projects plan to develop large-scale infrastructure, such as stations and observatories, in hitherto pristine areas. Fewer than one percent of Antarctic field projects address the issue of their environmental legacy: four projects indicated that the site will be cleaned up or the equipment will be removed at the end of the project; two projects indicated that their results may be useful for the management of the Antarctic environment, e.g., in the control of invasive species or setting up of marine protected areas. With the goal of increasing the environmental awareness of Antarctic field scientists, our contribution will review current research on the impacts of human activities science, tourism, exploitation of marine resources and global climate change - on the Antarctic environment. A preliminary analysis of the cumulative impacts of IPY activities will be presented. Case studies of scientific projects in Antarctica with a

  9. ‘Antarctic biology in the 21st century - Advances in, and beyond the international polar year 2007-2008

    NASA Astrophysics Data System (ADS)

    Stoddart, Michael

    2010-08-01

    The International Polar Year 2007-2008 (IPY) has provided an opportunity for biology to show itself as an important part of Antarctic science in a manner in which it was not seen during earlier Polar Years. Of the 15 endorsed biological projects in Antarctica, 7 included more than 20 scientists and could be deemed truly international. Four were conducted in the marine environment, and one each in the fields of biological invasions, microbial ecology, and terrestrial ecology, and one was SCAR’s over-arching ‘Evolution and Biodiversity in the Antarctic’. The marine projects have left a robust legacy of data for future research into the consequences of environmental change, and into future decisions about marine protected areas. Studies on introductions of exotic organisms reveal an ever-present threat to the warmer parts of the high-latitude Southern Ocean, or parts which might become warmer with climate change. Studies on microbial ecology reveal great complexity of ecosystems with high numbers of unknown species. Terrestrial research has shown how vulnerable the Antarctic is to accidental introductions, and how productive the soils can be under changed climate conditions. Antarctic biology has come-of-age during IPY 2007-2008 and the campaign has set the scene for future research.

  10. IPY EOC USA: U.S. Education, Outreach and Communication Efforts for the International Polar Year 2007-2008

    NASA Astrophysics Data System (ADS)

    McCaffrey, M. S.; Pfirman, S.

    2007-12-01

    As an international collaborative effort involving scientific organizations and scientists from over 60 nations to study the polar regions and their global linkages during an intensive observation period running from 2007 to 2009, the International Polar Year (IPY) is recognized as a unique and timely opportunity to communicate to broad audiences the dynamics of polar regions and their global connections. The overall international effort to develop specific education, outreach and communication (EOC) strategies and foster a broad community supporting IPY activities has benefitted from the planning of the U.S. Polar Research Board of the National Academies of Sciences, and from workshops funded and organized by the U.S. National Science Foundation, NOAA, Columbia University and the Cooperative Institute for Research in Environmental Sciences (CIRES). This paper will examine the history of these efforts, the challenges the community has faced in pursuing the opportunities, and the successes to date of the diverse array of programs and projects aimed at communicating the "who, what, where, how, when and why" of IPY activities to diverse, non-technical audiences.

  11. The International Polar Year, 2007-2008, an opportunity to focus on infectious diseases in Arctic regions.

    PubMed

    Parkinson, Alan J

    2008-01-01

    On 3 occasions over the past 125 years, scientists from around the world have worked together to organize scientific and exploration activities in polar regions (www.ipy.org). The first International Polar Year (IPY) in 1881-1884 marked the first major coordinated international scientific initiative to collect standardized meteorological and geophysical data in polar regions. Fifteen expeditions led by 12 nations amassed a large amount of data, but the scientific value was diminished by disjointed publication efforts and lack of long-term institutional commitment; lessons were learned and corrected in subsequent polar years. The second IPY began in 1932. Forty-four nations led expeditions in the Arctic and Antarctic, resulting in greater understanding of the aurora, magnetism, and meteorology. Air and marine navigation, radio operations, and weather forecasting were greatly improved as a result. The third IPY, in 1957-58, was renamed the International Geophysical Year and capitalized on technologic advances developed during World War II. Technologic and scientific momentum was redirected toward research, particularly to studies of the upper atmosphere, a legacy that continues to the present day. Notable achievements included launching the first satellite, measurement of atmospheric greenhouse gases, delineating the system of mid-ocean ridges, and confirming the theory of plate tectonics. PMID:18258069

  12. On the scaling laws derived from ice beacon trajectories in the southern Beaufort Sea during the International Polar Year - Circumpolar Flaw Lead study, 2007-2008

    NASA Astrophysics Data System (ADS)

    Lukovich, J. V.; Babb, D. G.; Barber, D. G.

    2011-09-01

    Sea ice motion is an important element in mass balance calculations, ice thermodynamic modeling, ice management plans for industry, and ecosystems studies. In the historical literature, sea ice motion in the Beaufort Sea was characterized by a predominantly anticyclonic motion during winter months, with episodic reversals to cyclonic activity during summer. However, recent studies have shown an increase in cyclonic activity throughout the annual cycle. In this paper we examine circulation in the Beaufort Sea based on the trajectories of 22 ice beacons launched in the Franklin Bay area during the International Polar Year - Circumpolar Flaw Lead (IPY-CFL) study during an over-wintering experiment in 2007-2008. Dispersion characteristics of ice motion show that absolute zonal dispersion follows a t2 scaling law characteristic of advection associated with Beaufort Gyre circulation, whereas absolute meridional dispersion follows a scaling law of t5/4 characteristic of floaters and dispersion in 2-D turbulence. Temporal autocorrelations of ice velocity fluctuations highlight definitive timescales with values of 1.2 (0.7) days in the zonal (meridional) direction. Near-Gaussian behavior is reflected in higher-order moments for ice velocity fluctuation probability density functions (pdfs). Non-Gaussian behavior for absolute displacement pdfs indicates spatial heterogeneity in the ice motion fields. Atmospheric forcing of sea ice is explored through analysis of daily North American Regional Reanalysis and in situ wind data, where it is shown that ice in the CFL study region travels with an average speed of approximately 0.2% and an average angle of 51.5° to the right of the surface winds during the 2007-2008 winter. The results from this analysis further demonstrate seasonality in ice drift to wind ratios and angles that corresponds to stress buoy data indicative of increases in internal ice stress and connectivity due to consolidation of the seasonal ice zone to the coast

  13. Closing the loop - Approaches to monitoring the state of the Arctic Mediterranean during the International Polar Year 2007-2008

    NASA Astrophysics Data System (ADS)

    Mauritzen, C.; Hansen, E.; Andersson, M.; Berx, B.; Beszczynska-Möller, A.; Burud, I.; Christensen, K. H.; Debernard, J.; de Steur, L.; Dodd, P.; Gerland, S.; Godøy, Ø.; Hansen, B.; Hudson, S.; Høydalsvik, F.; Ingvaldsen, R.; Isachsen, P. E.; Kasajima, Y.; Koszalka, I.; Kovacs, K. M.; Køltzow, M.; LaCasce, J.; Lee, C. M.; Lavergne, T.; Lydersen, C.; Nicolaus, M.; Nilsen, F.; Nøst, O. A.; Orvik, K. A.; Reigstad, M.; Schyberg, H.; Seuthe, L.; Skagseth, Ø.; Skarðhamar, J.; Skogseth, R.; Sperrevik, A.; Svensen, C.; Søiland, H.; Teigen, S. H.; Tverberg, V.; Wexels Riser, C.

    2011-07-01

    During the 4th International Polar Year 2007-2009 (IPY), it has become increasingly obvious that we need to prepare for a new era in the Arctic. IPY occurred during the time of the largest retreat of Arctic sea ice since satellite observations started in 1979. This minimum in September sea ice coverage was accompanied by other signs of a changing Arctic, including the unexpectedly rapid transpolar drift of the Tara schooner, a general thinning of Arctic sea ice and a double-dip minimum of the Arctic Oscillation at the end of 2009. Thanks to the lucky timing of the IPY, those recent phenomena are well documented as they have been scrutinized by the international research community, taking advantage of the dedicated observing systems that were deployed during IPY. However, understanding changes in the Arctic System likely requires monitoring over decades, not years. Many IPY projects have contributed to the pilot phase of a future, sustained, observing system for the Arctic. We now know that many of the technical challenges can be overcome. The Norwegian projects iAOOS-Norway, POLEWARD and MEOP were significant ocean monitoring/research contributions during the IPY. A large variety of techniques were used in these programs, ranging from oceanographic cruises to animal-borne platforms, autonomous gliders, helicopter surveys, surface drifters and current meter arrays. Our research approach was interdisciplinary from the outset, merging ocean dynamics, hydrography, biology, sea ice studies, as well as forecasting. The datasets are tremendously rich, and they will surely yield numerous findings in the years to come. Here, we present a status report at the end of the official period for IPY. Highlights of the research include: a quantification of the Meridional Overturning Circulation in the Nordic Seas (“ the loop”) in thermal space, based on a set of up to 15-year-long series of current measurements; a detailed map of the surface circulation as well as

  14. The optical and physical properties of atmospheric aerosols over the Indian Antarctic stations during southern hemispheric summer of the International Polar Year 2007-2008

    NASA Astrophysics Data System (ADS)

    Chaubey, Jai Prakash; Krishna Moorthy, K.; Babu, S. Suresh; Nair, Vijayakumar S.

    2011-01-01

    The properties of background aerosols and their dependence on meteorological, geographical and human influence are examined using measured spectral aerosol optical depth (AOD), total mass concentration (MT) and derived number size distribution (NSD) over two distinct coastal locations of Antarctica; Maitri (70° S, 12° E, 123 m m.s.l.) and Larsemann Hills (LH; 69° S, 77° E, 48 m m.s.l.) during southern hemispheric summer of 2007-2008 as a part of the 27th Indian Scientific Expedition to Antarctica (ISEA) during International Polar Year (IPY). Our investigations showed comparable values for the mean columnar AOD at 500 nm over Maitri (0.034±0.005) and LH (0.032±0.006) indicating good spatial homogeneity in the columnar aerosol properties over the coastal Antarctica. Estimation of Angstrom exponent α showed accumulation mode dominance at Maitri (α~1.2±0.3) and coarse mode dominance at LH (0.7±0.2). On the other hand, mass concentration (MT) of ambient aerosols showed relatively high values (≈8.25±2.87 μg m-3) at Maitri in comparison to LH (6.03±1.33 μg m-3).

  15. Upper-ocean hydrography of the Nordic Seas during the International Polar Year (2007-2008) as observed by instrumented seals and Argo floats

    NASA Astrophysics Data System (ADS)

    Isachsen, Pål E.; Sørlie, Signe R.; Mauritzen, Cecilie; Lydersen, Christian; Dodd, Paul; Kovacs, Kit M.

    2014-11-01

    Following indications of recent warming trends in the Nordic Seas, we have studied the hydrography of these marginal seas from the summer of 2007 until the fall of 2008, using observations gathered by instrumented seals and Argo floats. The combined dataset shows that the upper ocean was indeed both warmer and saltier over much of the Nordic Seas in 2007-2008 compared to the average ocean state for the period 1956-2006 (based on the World Ocean Atlas 2009). There are also indications that the surface Polar Waters of the East Greenland Current were colder and fresher than the climatology, though the quality of the climatology is questionable for this region given the low number of historical observations. Dynamic height calculations suggest that the observed hydrographic changes were associated with enhanced northward upper-ocean thermal wind transport in the east and possibly also enhanced southward transport in the west.

  16. Role of the Polar Research Board in Facilitating Planning for IPY 2007-2008

    NASA Astrophysics Data System (ADS)

    Elfring, C.

    2003-12-01

    IPY 2007-2008 has the potential to be a valuable burst of scientific activity that adds to our understanding of polar regions and their role in the global system, and it stands to engage a new generation of scientists and the public in an exciting way. IPY 2007-2008 will be truly international and broadly multidisciplinary. But how is something of this scale planned and implemented? Where are the opportunities for input from the science community? How do we reconcile the differences in the American system of supporting science with approaches used in other nations, when attempting to work jointly? How can the large, diverse polar science community be satisfied that IPY reflects their priorities, given the necessity of making choices about how to focus IPY activities? The National Academy of Sciences played a key role in organizing the International Geophysical Year in 1957-1958. In this mode, the Polar Research Board, a unit of the National Academies (which includes the National Academy of Sciences, National Academy of Engineering, and Institute of Medicine), is attempting to play a role in facilitating IPY 2007-2007 planning. The Polar Research Board is a nongovernmental body composed of volunteers from the polar science community. Its mission is to promote excellence in polar science and provide advice to agencies and the nation on issues of importance in the Arctic, Antarctic, and cold regions in general. The PRB represents US interests in two international nongovernmental polar science organizations - the Scientific Committee on Antarctic Research (SCAR) and the International Arctic Science Committee (IASC). The PRB's status as an independent body gives it a special role in organizing IPY 2007-2008 at both the national and international levels. At the national level, it has attempted to provide opportunities for dialog on what US scientists would like IPY to be, and to have a relatively open process so that bottom-up ideas can be considered. At the

  17. International Rules for Precollege Science Research: Guidelines for Science and Engineering Fairs, 2007-2008

    ERIC Educational Resources Information Center

    Science Service, 2007

    2007-01-01

    This publication presents changes and modifications for 2007-2008 to the "International Rules for Precollege Science Research: Guidelines for Science and Engineering Fairs." It is written to guide fair directors, teachers, scientists, parents, and adult volunteers as they pursue their work of encouraging students to explore and investigate their…

  18. Recruiting Trends, 2007-2008

    ERIC Educational Resources Information Center

    Collegiate Employment Research Institute (NJ3), 2008

    2008-01-01

    This paper presents the recruiting trends for 2007-2008. This year's report is based on 994 respondents, including 84 K-12 school districts. The researchers focused attention on growing companies, based on lists from Forbes and Inc. magazines, and as a result, they have more small and medium-size employers represented this year. The sample…

  19. ARL Statistics 2007-2008

    ERIC Educational Resources Information Center

    Kyrillidou, Martha, Comp.; Bland, Les, Comp.

    2009-01-01

    "ARL Statistics 2007-2008" is the latest in a series of annual publications that describe collections, staffing, expenditures, and service activities for the 123 members of the Association of Research Libraries (ARL). Of these, 113 are university libraries; the remaining 10 are public, governmental, and nonprofit research libraries. Data reported…

  20. Recent advance in polar seismology: Global impact of the International Polar Year

    NASA Astrophysics Data System (ADS)

    Kanao, Masaki; Zhao, Dapeng; Wiens, Douglas A.; Stutzmann, Éléonore

    2015-03-01

    The most exciting initiative for the recent polar studies was the International Polar Year (IPY) in 2007-2008. The IPY has witnessed a growing community of seismologists who have made considerable efforts to acquire high-quality data in polar regions. It also provided an excellent opportunity to make significant advances in seismic instrumentation of the polar regions to achieve scientific targets involving global issues. Taking these aspects into account, we organize and publish a special issue in Polar Science on the recent advance in polar seismology and cryoseismology as fruitful achievements of the IPY.

  1. Prevalence of internal parasites in beef cows in the United States: Results of the National Animal Health Monitoring System's (NAHMS) beef study, 2007-2008.

    PubMed

    Stromberg, Bert E; Gasbarre, Louis C; Ballweber, Lora R; Dargatz, David A; Rodriguez, Judith M; Kopral, Christine A; Zarlenga, Dante S

    2015-10-01

    During the United States Department of Agriculture (USDA) National Animal Health Monitoring System's (NAHMS) 2007-2008 beef study, 567 producers from 24 US States were offered the opportunity to collect fecal samples from weaned beef calves and have them evaluated for the presence of parasite eggs (Phase 1). Participating producers were provided with instructions and materials for sample collection. Up to 20 fresh fecal samples were collected from each of the 99 participating operations. Fresh fecal samples were submitted to one of 3 randomly assigned laboratories for evaluation. Upon arrival at the laboratories, all samples were processed for the enumeration of strongyle, Nematodirus, and Trichuris eggs using the modified Wisconsin technique. The presence or absence of coccidian oocysts and tapeworm eggs was also noted. In submissions where the strongyle eggs per gram exceeded 30, aliquots from 2 to 6 animals were pooled for DNA extraction. Extracted DNA was subjected to genus level polymerase chain reaction (PCR) identification for the presence of Ostertagia, Cooperia, Haemonchus, Oesophagostomum, and Trichostrongylus. In this study, 85.6% of the samples had strongyle type, Nematodirus, and Trichuris eggs. Among the samples evaluated, 91% had Cooperia, 79% Ostertagia, 53% Haemonchus, 38% Oesophagostomum, 18% Nematodirus, 7% Trichuris, and 3% Trichostrongylus. The prevalence of coccidia and tapeworm eggs was 59.9% and 13.7%, respectively. PMID:26424909

  2. ARL Annual Salary Survey 2007-2008

    ERIC Educational Resources Information Center

    Kyrillidou, Martha, Comp; Young, Mar, Comp.; Barber, Jason, Comp.

    2008-01-01

    The "ARL Annual Salary Survey 2007-2008" reports salary data for all professional staff working in Association of Research Libraries (ARL) libraries. It is the most comprehensive and thorough guide to current salaries in large U.S. and Canadian academic and research libraries, and is a valuable management and research tool. Data for 9,983…

  3. ARL Supplementary Statistics, 2007-2008

    ERIC Educational Resources Information Center

    Bland, Les, Comp.; Kyrillidou, Martha, Comp.

    2009-01-01

    This report presents statistics on how Association of Research Libraries (ARL) member libraries spend money on electronic resources. This report indicates that 109 ARL libraries purchased 32,329,187 electronic books. In 2007-2008, there was a median of 28,319 acquisitions of electronic books by ARL libraries (this includes one institution that…

  4. Polarized internal target apparatus

    DOEpatents

    Holt, R.J.

    1984-10-10

    A polarized internal target apparatus with a polarized gas target of improved polarization and density (achieved by mixing target gas atoms with a small amount of alkali metal gas atoms, and passing a high intensity polarized light source into the mixture to cause the alkali metal gas atoms to become polarized which interact in spin exchange collisions with target gas atoms yielding polarized target gas atoms) is described.

  5. Polarized internal target apparatus

    DOEpatents

    Holt, Roy J.

    1986-01-01

    A polarized internal target apparatus with a polarized gas target of improved polarization and density achieved by mixing target gas atoms with a small amount of alkali metal gas atoms, and passing a high intensity polarized light source into the mixture to cause the alkali metal gas atoms to become polarized which interact in spin exchange collisions with target gas atoms yielding polarized target gas atoms.

  6. Satellite Observations From the International Polar Year

    NASA Astrophysics Data System (ADS)

    Jezek, Kenneth; Drinkwater, Mark

    2010-04-01

    To realize the benefit of the growing number of international satellites to the scientific objectives of the 2007-2008 International Polar Year (IPY), the Global Interagency IPY Polar Snapshot Year (GIIPSY) was established in November 2005 to develop a consensus on polar science requirements and objectives for IPY that could best and perhaps only be met using the Earth-observing satellites. Requirements focused on all aspects of the cryosphere and ranged from sea ice and ice sheets to permafrost and snow cover. Individual topics included how best to develop high-resolution digital elevation models of outlet glaciers using stereo-optical systems, measure ice sheet surface velocity using interferometric synthetic aperture radar (InSAR), and repeatedly measure sea ice motion using optical and microwave imaging instruments. Because of this foresight, several IPY science objectives were well met using satellite observations, allowing a wealth of valuable data to be collected on cryospheric processes (Figure 1). Further, the framework for coordinating these remote sensing efforts serves as a valuable model for future coordinated efforts to monitor cryospheric dynamics.

  7. Geoeffectiveness of Stream Interaction Regions during 2007-2008

    NASA Astrophysics Data System (ADS)

    Sanchez-Garcia, Elsa; Aguilar-Rodriguez, Ernesto; Ontiveros, Veronica

    2016-07-01

    The Stream Interaction Regions (SIRs) are generated in the interplanetary medium when a fast solar wind stream overtakes a slower one. If these large-scale phenomena interact with the Earth's magnetosphere they can give rise to geomagnetic storms (GSs). In this study we analyze the degree of geoeffectiveness of 20 events that were generated by SIRs. The events were observed during the 2007-2008 period that comprising the extended downward phase of solar cycle 23. The degree of geoeffectivity is measured using magnetic indices from different latitudes: PCN (Polar cap north), PCS (polar cap south), AA (antipodal amplitude), AE (Auroral Electrojet), Kp (estimated global index) and Dst (Disturbance storm time). We discuss some results on the correlation of these magnetic indices with the characteristics of shocks associated with the SIRs observed by STEREO-A/B, WIND and ACE spacecraft. All the 20 SIRs events generated GSs with Dst values in ranging from -86 nT up to -12 nT. Moreover, 6 out of the 20 events presented storm sudden commencement (SSC). We also discuss on the characteristics of the SIR-associated shocks and the intensity of the GSs.

  8. The IPY 2007-2008 data legacy - creating open data from IPY publications

    NASA Astrophysics Data System (ADS)

    Driemel, A.; Grobe, H.; Diepenbroek, M.; Grüttemeier, H.; Schumacher, S.; Sieger, R.

    2015-09-01

    The International Polar Year (IPY) 2007-2008 was a synchronized effort to simultaneously collect data from polar regions. Being the fourth in a series of IPYs, the demand for interdisciplinarity and new data products was high. However, despite all the research done on land, people, ocean, ice and atmosphere and the large amount of data collected, no central archive or portal was created for IPY data. In order to improve the availability and visibility of IPY data, a concerted effort between PANGAEA - Data Publisher for Earth and Environmental Science, the International Council for Science (ICSU) World Data System (WDS), and the International Council for Scientific and Technical Information (ICSTI) was undertaken to extract data resulting from IPY publications for long-term preservation. Overall, 1380 IPY-related references were collected. Of these, only 450 contained accessible data. All data were extracted, quality checked, annotated with metadata and uploaded to PANGAEA. The 450 articles dealt with a multitude of IPY topics - plankton biomass, water chemistry, ice thickness, whale sightings, Inuit health, alien species introductions by travellers or tundra biomass change, to mention just a few. Both the Arctic and the Antarctic were investigated in the articles, and all realms (land, people, ocean, ice and atmosphere) and a wide range of countries were covered. The data compilation can now be found with the identifier http://dx.doi.org/10.1594/PANGAEA.150150, and individual parts can be searched using the PANGAEA search engine (http://www.pangaea.de) and adding "+project:ipy". With this effort, we hope to improve the visibility, accessibility and long-term storage of IPY data for future research and new data products.

  9. IPY 2007-2008 data legacy - a ong story cut short

    NASA Astrophysics Data System (ADS)

    Driemel, A.; Grobe, H.; Diepenbroek, M.; Grüttemeier, H.; Schumacher, S.; Sieger, R.

    2015-06-01

    The International Polar Year 2007-2008 was a synchronized effort to simultaneously collect data from polar regions. Being the fourth in a row of IPYs, the demand for interdisciplinarity and new data products was high. However, despite of all the research done on land, people, ocean, ice and atmosphere and the large amount of data collected, no central archive or portal was created for IPY data. In order to address these issues, a concerted effort between PANGAEA - Data Publisher for Earth and Environmental Science, the ICSU World Data System (WDS), and the International Council for Scientific and Technical Information (ICSTI) was undertaken to extract data resulting from IPY publications for long-term preservation. 1380 IPY-related references were collected. Out of these, only 450 contained accessible data. All data was extracted, quality checked, annotated with metadata and uploaded to PANGAEA. The 450 articles dealt with a multitude of IPY topics - plankton biomass, water chemistry, ice thickness, whale sightings, Inuit health, alien species introductions by travelers or tundra biomass change - to mention just a few. Both, the Arctic and the Antarctic were investigated in the articles, and all realms (land, people, ocean, ice and atmosphere) and a wide range of countries were covered. The data compilation can now be found with the identifier doi:10.1594/PANGAEA.150150 and individually searched for using the PANGAEA search engine (www.pangaea.de) and adding "+project:ipy". With this effort, we hope to improve the visibility, accessibility and long-term storage of IPY data for future research and new data products.

  10. Tracking the Publications of the International Polar Year

    NASA Astrophysics Data System (ADS)

    Tahirkheli, S. N.; Goodwin, R.; Lane, H.

    2006-12-01

    Publications that result from the International Polar Year 2007-2008 (IPY) will be identified and indexed in the International Polar Year Publications Database (IPYPD). A network of four organizations will collaborate to attempt to compile and provide access to all IPY-related publications through a single database. This network includes the Arctic Science and Technology Information System (ASTIS), the Cold Regions Bibliography Project (CRBP), the Scott Polar Research Institute (SPRI) Library and National Information Services Corporation (NISC). Publications that result from research as well as publications that relate to outreach and education will be covered. The IPYPD, as part of the IPY Data and Information Service (IPYDIS) will use the IPY Data Policy to require that researchers report their publications to either ASTIS, CRBP or the SPRI library. Each of these organizations will include records for IPY publications in their existing databases which are part of the Arctic & Antarctic Regions database distributed by NISC. NISC will copy the IPY records into the separate IPY Publications Database. The comprehensiveness and size of the final database will depend on the success of fundraising, on the total number of publications that result from the IPY and on the cooperation of researchers in reporting their publications.

  11. ARL Academic Health Sciences Library Statistics, 2007-2008

    ERIC Educational Resources Information Center

    Kyrillidou, Martha, Comp.; Bland, Les, Comp.

    2009-01-01

    This document presents data that describe collections, expenditures, personnel, and services in 64 medical libraries at Association of Research Libraries (ARL) member institutions throughout North America. In 2007-2008, the reporting health sciences libraries held a median of 240,955 volumes, spent a total of $240,019,298, and employed 2,304…

  12. Southeastern Wisconsin School District Rankings, 2007-2008

    ERIC Educational Resources Information Center

    Public Policy Forum, 2008

    2008-01-01

    This brochure displays the following data for seven counties in southeastern Wisconsin for the 2007-2008 school year: (1) Total operations expenditures; (2) Property tax revenue; (3) Total enrollment; (4) One-year change in enrollment; (5) Minority enrollment; (6) Free or reduced lunch; (7) Graduation rate; (8) 3rd, 4th, 8th and 10th grade…

  13. ARL Academic Law Library Statistics, 2007-2008

    ERIC Educational Resources Information Center

    Kyrillidou, Martha, Comp.; Bland, Les, Comp.

    2009-01-01

    This document presents results of the 2007-2008 Association of Research Libraries (ARL) Law Library Statistics Questionnaire. Of 113 ARL university libraries, 74 responded to the survey. Results for each library are presented in the following data tables: (1) collections (2-parts), including volumes in library, volumes added, monographs purchased,…

  14. Handbook of Procedures for the Graduation Program 2007-2008

    ERIC Educational Resources Information Center

    British Columbia Ministry of Education, 2007

    2007-01-01

    This 2007-2008 manual, "Handbook of Procedures for the Graduation Program," has been approved by the British Columbia Minister of Education on July 18, 2007 for the purpose of setting out graduation requirements. The handbook outlines procedures for efficiently sharing student data between schools and the Ministry of Education, and answers…

  15. An Overview of the Upcoming International Polar Year

    NASA Astrophysics Data System (ADS)

    Carlson, D.

    2006-05-01

    The ICSU - WMO International Polar Year 2007 - 2008 has drawn extraordinary interest from scientists of many specialties and many nationalities. A cautious assessment prior to the IPY start shows more than 200 projects, each with at least10 and often 50 or more scientists from at least three different nations, addressing a wide range of physical, biological and social research topics in both polar regions. Adding students, engineers, technicians and all manner of talented support crew so essential to polar research, and accepting some limitations due to logistics and funding, it seems likely that IPY will involve several 10's of thousands of individuals from at least 60 nations. Much of the IPY research will represent redirection and new collaboration on the basis of existing funds, but several nations will implement substantial new research funding and enhanced logistical support during IPY. One of IPY's strongest scientific contributions will arise from a substantial effort to understand geophysical, biological, and even social linkages between northern and southern polar regions - these linkages will highlight the importance of polar science to global processes and issues. IPY will offer unprecedented data management and communication challenges and opportunities, internally among so broad a range of scientific disciplines and externally to science education systems at all levels and to the general public. Against a background of prominent and largely commercial events, including films, television series, museum exhibitions, and regular broadcast coverage, many polar institutions and individuals will consider local events, new educational materials, and new engagement strategies that can have an enormous impact on public perception of science. In its total science and outreach effort, IPY will provide a large step forward that AGU and other pre-eminent science organizations can use and should plan to sustain.

  16. Internal polarization limits coronagraph contrast

    NASA Astrophysics Data System (ADS)

    Breckinridge, James Bernard; Lam, Wai Sze T.; Chipman, Russell A.

    2015-08-01

    The performance of exoplanet imaging coronagraphs is limited by internal polarization. The point spread function (PSF) of these systems is determined by the details of the opto-mechanical layout selected to package the system and by the highly reflective metal thin films needed to maintain high optical system transmittance. To obtain the high contrast levels needed for terrestrial exoplanet science requires a comprehensive understanding of the vector electromagnetic wave from the source through the system. The literature contains many studies of polarization transmissivity of telescopes and instruments for the purpose of photo-polarimetry. Here we report for the first time the effects of polarization on high-performance image quality.We modeled a typical 2.4-meter Cassegrain telescope system with one 90-degree fold mirror and analyzed the system for polarization aberrations.We find: 1. The image plane irradiance distribution is the linear superposition of four PSF images: One for each of the two orthogonal polarizations and one for each of two cross-product polarization terms. 2. The PSF image is brighter by 9% for one polarization component compared to its orthogonal state. 3. The image of the PSF for orthogonal components are shifted across the focal plane with respect to each other, causing the PSF image for astronomical sources (polarized or unpolarized) to become slightly elongated (elliptical) with a centroid separation of about 0.6 masec. 4. The orthogonally polarized components of unpolarized sources contain different wavefront aberrations, which are separated by approximately 32 milliwaves. This implies that a wavefront correction system cannot optimally correct the aberrations for all polarizations simultaneously. 5. The polarization aberrations couple small parts (~1E-5) of each polarization component of the light into the orthogonal polarization to create highly distorted secondary, or “ghost” PSF image.. The radius of the spatial extent of the 90

  17. Rayleigh Lidar Network Observations and Analysis of the Evolution of the Arctic Middle Atmosphere during the IPY Winter 2007-2008

    NASA Astrophysics Data System (ADS)

    Collins, R. L.; Harvey, V. L.; Thurairajah, B.; Atkinson, D. E.; Larsen, C. J.; Baumgarten, G.; Fiedler, J.; Firanski, B. J.; Gerding, M.; Hoeffner, J.; Livingston, J. M.; Luebken, F.; Mizutani, K.; Pan, W.; Sica, R. J.; Strawbridge, K. B.

    2008-12-01

    A network of five Rayleigh lidars (i.e., Kuehlungsborn, Germany (54N, 12E), Chatanika, USA (65N, 147W), Kangerlussuaq, Greenland (67N, 51W), Andoya, Norway (69N, 16E), and Eureka, Canada (80N, 86W)) has been used to measure middle atmosphere temperature profiles through the 2007-2008 winter and spring. These measurements are being made as part of the project Pan-Arctic Studies of the Coupled Tropospheric, Stratospheric and Mesospheric Circulation as part of the Fourth International Polar Year (IPY-4). This project is a component of the two full IPY proposals; International Arctic Systems for Observing the Atmosphere (IASOA) and The Structure and Evolution of the Polar Stratosphere and Mesosphere and Links to the Troposphere during IPY (SPARC-IPY). The lidar network is part of the Arctic Observing Network (AON). The resolution and distribution of these lidar measurements provides the basis for a pan-Arctic perspective of the middle atmosphere circulation. We combine these lidar data with satellite observations and meteorological re-analyses to study the structure, evolution, and variability of the Arctic stratospheric vortex and Aleutian anticyclone. In this study we present the evolution of the Arctic middle atmosphere during the winter of 2007-2008. We highlight a stratospheric warming event that occurred during 20-26 February 2008. During this week the vortex was disrupted by the Aleutian anticyclone, then split at higher altitudes, and eventually reformed. The lidar measurements show that the altitude and temperature of the stratopause vary considerably (10 km, 30 K) from night-to-night and that the observed temperature structure often differs from that reported by the standard climatologies (e.g., SPARC). We discuss the observations in terms of the Study of Environmental Arctic Change (SEARCH).

  18. Flavonoid Values for USDA Survey Foods and Beverages 2007-2008: Provisional Flavonoid Addendum, FNDDS 4.1 and Flavonoid Intake Data, WWEIA, NHANES 2007-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This release of the Flavonoid Values for Survey Foods and Beverages 2007-2008 makes possible, for the first time, calculation of flavonoid intakes based on all foods and beverages reported in national surveys. This release has two components. The first component is an addendum to USDA’s Food and N...

  19. Portugal and the International Polar Year: the role of researchers in promoting education and outreach activities to a wider audience

    NASA Astrophysics Data System (ADS)

    Mendes-Victor, L. A.; Xavier, J.; Vieira, G.; Canário, A.; Santos, C. R.

    2007-12-01

    Thanks to the International Polar Year (IPY), international programme of research and education, aiming to promote collaborative research in Polar regions in 2007-08, Portugal has been proposing to play an active role in various research disciplines. The main objectives, designed by the Portuguese Committee were: improving the knowledge in polar processes, implementing the capacity to detect climate change, assessing the global warming consequences in the preservation of marine and terrestrial biodiversity, and finally, attracting the people's attention to all these issues. Another one of the greatest objectives of the Portuguese Committee for the IPY, coordinated by Portuguese researchers, is to encourage activities and events related to Polar Regions, directed to the general public. The establishment of new collaborations with education institutions (e.g. Ministry of Education), schools, Universities and teacher associations has been already obtained. This presentation aims to show the educational programme "LATITUDE60!", that focuses on education and outreach activities (E&O) conducted in Portugal, emphasizing the various projects related to education for 2007- 2008, and focus on the importance of attracting the attention of the general public (from children to adults) to Portuguese activities and to the Science in the Polar Regions. It has been recognized internationally by taking the forefront of E&O within the International Polar Year. The work related to education and science outreach, during the IPY, has been coordinated in collaboration with the International Polar Year Education & Outreach Sub-Committee as well as with the International Youth Steering Committee for the International Polar Year.

  20. International Polar Research and Space Weather

    NASA Astrophysics Data System (ADS)

    Lanzerotti, Louis J.

    2009-02-01

    The fiftieth anniversary of the International Geophysical Year (IGY), currently celebrated in the 2007-2009 International Polar Year (IPY), highlights space weather's heritage from polar research. The polar regions were still very much "terra incognito" 50 years ago. At the same time, communications technologies had significantly advanced since the time of the second IPY, in 1932-1933. Yet even before the second IPY, several directors of international meteorological services stated in a 1928 resolution that "increased knowledge [of the polar regions] will be of practical application to problems connected with terrestrial magnetism, marine and aerial navigation, wireless telegraphy and weather forecasting" (see http://scaa.usask.ca/gallery/northern/currie/en_polaryear.shtml).

  1. Mitotic internalization of planar cell polarity proteins preserves tissue polarity.

    PubMed

    Devenport, Danelle; Oristian, Daniel; Heller, Evan; Fuchs, Elaine

    2011-08-01

    Planar cell polarity (PCP) is the collective polarization of cells along the epithelial plane, a process best understood in the terminally differentiated Drosophila wing. Proliferative tissues such as mammalian skin also show PCP, but the mechanisms that preserve tissue polarity during proliferation are not understood. During mitosis, asymmetrically distributed PCP components risk mislocalization or unequal inheritance, which could have profound consequences for the long-range propagation of polarity. Here, we show that when mouse epidermal basal progenitors divide PCP components are selectively internalized into endosomes, which are inherited equally by daughter cells. Following mitosis, PCP proteins are recycled to the cell surface, where asymmetry is re-established by a process reliant on neighbouring PCP. A cytoplasmic dileucine motif governs mitotic internalization of atypical cadherin Celsr1, which recruits Vang2 and Fzd6 to endosomes. Moreover, embryos transgenic for a Celsr1 that cannot mitotically internalize exhibit perturbed hair-follicle angling, a hallmark of defective PCP. This underscores the physiological relevance and importance of this mechanism for regulating polarity during cell division. PMID:21743464

  2. American Council of Learned Societies Annual Report, 2007-2008

    ERIC Educational Resources Information Center

    American Council of Learned Societies, 2009

    2009-01-01

    The American Council of Learned Societies (ACLS) provides the humanities and related social sciences with leadership, opportunities for innovation, and national and international representation. ACLS was founded in 1919 to represent the United States in the Union Academique Internationale. Its mission is "the advancement of humanistic studies in…

  3. New York City International Polar Weekend at the American Museum of Natural History

    NASA Astrophysics Data System (ADS)

    Pfirman, S.; Turrin, M.; Macphee, R.

    2008-12-01

    The American Museum of Natural History, in partnership with Lamont-Doherty Earth Observatory and the Earth Institute of Columbia University and Barnard College, is featuring the International Polar Year through a New York City International Polar Weekend (NYC-IPW) in 2007, 2008 and 2009. The event showcases current polar research, polar environmental changes, history and culture during two days of family programs and activities, performances, and lectures. The goal of the NYC-IPW is to engage diverse audiences and enhance the public understanding of polar science, in particular IPY research, through close interactions with polar experts. Activities for the public include many disciplines, ranging from the physical sciences and cultural anthropology to music and art, and are presented in many forms, from lectures, panels and films to posters and play. Highlights of the NYC-IPW include: 1) A polar fair for youth and adults, showcasing scientists, artists, and educators who have worked at one or both poles and including many interactive exhibits featuring such topics as life in New York at the end of the last Ice Age, how Arctic sea ice is changing, and life on and under the ice. 2) Performances and presentations oriented towards children and families, including Inuit Throat Singers, Central Park Zoo Theater Group, and a northern lights show. 3) Lectures showcasing current IPY research and addressing such issues as the possible effects of climate change on the poles and the rest of the world, as well as polar poetry, art and film. 4) A partnership with New York City Urban Advantage program for Middle School students in the city to meet with scientists, teachers and students who had participated in polar research and travel. 5) Norwegian Consulate sponsorship of science presenters and Sami performers. The March 2007 event involved 85 presenters and volunteers from 22 institutions, and attracted ca. 3,500 visitors. Approximately 5,000 visitors attended the February 2008

  4. The International Polar Year: Making Data and Information Available for the Long Term

    NASA Astrophysics Data System (ADS)

    Duerr, R. E.; Parsons, M. A.; Weaver, R.

    2004-12-01

    Planning is currently underway for an International Polar Year (IPY) in 2007-2008. Like its predecessors, the IPYs of 1882-83 and 1932-33 and the International Geophysical Year in 1957-58 IPY's (and IGY's), the upcoming IPY will undoubtedly produce a wide variety of data and information useful not only to the current generation; but also for future generations. However, unlike previous IPY/IGYs, the bulk of that data and information is likely to be digital not analog. While preservation of anything for the long term is problematic at best, at least the technologies needed for preserving analog materials (paper documents, photos, maps, etc.) are well understood and have passed the test of time. The same can not yet be said for digital data. As NSF and the Library of Congress have so eloquently stated, "digital objects require constant and perpetual maintenance, and they depend on elaborate systems of hardware, software, data and information models, and standards that are upgraded or replaced every few years." How future generations judge the success of the IPY of 2007-08 will be based, at least partly on whether the data and information collected is still readily accessible. This presentation will discuss what is needed in order to ensure the availability of IPY data for future generations.

  5. Review of polarized internal gas targets

    NASA Astrophysics Data System (ADS)

    Rathmann, Frank

    2002-03-01

    Experiments utilizing polarized internal gas targets are discussed. Since a few years these targets are used at electron and proton machines and considerable progress has been made in operating them on a routinely basis. This paper will focus on experimental aspects, such as the design and construction of storage cells and different methods employed for polarimetry.

  6. Review of polarized internal gas targets

    NASA Astrophysics Data System (ADS)

    Rathmann, Frank

    2000-06-01

    Experiments utilizing polarized internal gas targets will be reviewed. Since a few years these targets are being used at electron and proton machines and the progress made in operating these targets on a routinely basis has been pronounced. This paper will focus on experimental aspects, such as the design and construction of storage cells and different methods employed for polarimetry.

  7. Establishing the Baseline Height and Weight Status of New Hampshire Head Start Children, 2007-2008

    ERIC Educational Resources Information Center

    Blaney, David D.; Flynn, Regina T.; Martin, Nancy R.; Anderson, Ludmila

    2010-01-01

    We report on a standardized survey of height and weight status of children attending the New Hampshire Head Start Program during the 2007-2008 school year. Baseline prevalence estimates of overweight and obesity are needed for obesity prevention activities and intervention. We selected a random one-stage cluster sample and screened 629 children…

  8. 2007-2008 What We Eat In America, NHANES Tables 1-36

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Food Surveys Research Group of the Beltsville Human Nutrition Research Center has analyzed dietary data from the What We Eat In America (WWEIA), National Health and Nutrition Examination Survey (NHANES) 2007-2008 and released 36 summary data tables for the current 2-year survey release. The tab...

  9. Annual Report: Discipline, Crime, and Violence, School Year 2007-2008

    ERIC Educational Resources Information Center

    Virginia Department of Education, 2009

    2009-01-01

    The "Code of Virginia" requires school divisions statewide to submit data to the Virginia Department of Education (VDOE) on incidents of discipline, crime, and violence (DCV). School divisions began reporting such data in 1991. This annual report focuses primarily on DCV data submitted for school year 2007-2008, with selected comparisons to prior…

  10. South Carolina Commission on Higher Education Mission Resource Requirements (MRR), FY 2007-2008

    ERIC Educational Resources Information Center

    South Carolina Commission on Higher Education, 2007

    2007-01-01

    The Mission Resource Requirement (MRR) represents the level of funding necessary for an institution given its mission, size, and complexity of programs, based on regional and national norms, and the amount of the previous year's appropriation. This document is the MRR for the South Carolina Commission on Higher Education for Fiscal Year 2007-2008.…

  11. 2007/2008 Employer Satisfaction Survey Employers of Alberta High School Graduates

    ERIC Educational Resources Information Center

    Alberta Education, 2008

    2008-01-01

    The 2007/2008 Employer Satisfaction Survey was commissioned by Alberta Education and Alberta Advanced Education and Technology. Data collection for the survey was conducted by CCI Research Inc. between December 1st, 2007 and January 11th, 2008. The objective of the survey was to assess employer satisfaction with recent graduates from Alberta's…

  12. Facing Race: Illinois Legislative Report Card on Racial Equity, 2007-2008

    ERIC Educational Resources Information Center

    Morita, Josina; Keleher, Terry

    2008-01-01

    This publication reviews 56 bills introduced in the 95th General Assembly that, if signed into law by the Governor, would have the most direct positive and negative impacts on communities of color. The "2007-2008 Illinois Legislative Report Card on Racial Equity" evaluates the Governor and legislators on their responses to these initiatives.…

  13. What We Eat In America, NHANES 2007-2008: Documentation and Data Files

    Technology Transfer Automated Retrieval System (TEKTRAN)

    New nationwide dietary intake data were collected in What We Eat In America (WWEIA), National Health and Nutrition Examination Survey (NHANES) for the years 2007-2008 and are now available for public use. Two days of dietary intake data are included for most participants. The dietary interview data ...

  14. 7 CFR 982.255 - Free and restricted percentages-2007-2008 marketing year.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Free and Restricted Percentages § 982.255 Free and... merchantable hazelnuts for the 2007-2008 marketing year shall be 8.1863 and 91.8137 percent, respectively. (b) On May 1, 2008, the final free and restricted percentages for merchantable hazelnuts for the...

  15. 7 CFR 982.255 - Free and restricted percentages-2007-2008 marketing year.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Free and Restricted Percentages § 982.255 Free and... merchantable hazelnuts for the 2007-2008 marketing year shall be 8.1863 and 91.8137 percent, respectively. (b) On May 1, 2008, the final free and restricted percentages for merchantable hazelnuts for the...

  16. 7 CFR 982.255 - Free and restricted percentages-2007-2008 marketing year.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Free and Restricted Percentages § 982.255 Free and... merchantable hazelnuts for the 2007-2008 marketing year shall be 8.1863 and 91.8137 percent, respectively. (b) On May 1, 2008, the final free and restricted percentages for merchantable hazelnuts for the...

  17. 7 CFR 982.255 - Free and restricted percentages-2007-2008 marketing year.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Free and Restricted Percentages § 982.255 Free and... merchantable hazelnuts for the 2007-2008 marketing year shall be 8.1863 and 91.8137 percent, respectively. (b) On May 1, 2008, the final free and restricted percentages for merchantable hazelnuts for the...

  18. 7 CFR 982.255 - Free and restricted percentages-2007-2008 marketing year.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON Free and Restricted Percentages § 982.255 Free and... merchantable hazelnuts for the 2007-2008 marketing year shall be 8.1863 and 91.8137 percent, respectively. (b) On May 1, 2008, the final free and restricted percentages for merchantable hazelnuts for the...

  19. Building AN International Polar Data Coordination Network

    NASA Astrophysics Data System (ADS)

    Pulsifer, P. L.; Yarmey, L.; Manley, W. F.; Gaylord, A. G.; Tweedie, C. E.

    2013-12-01

    In the spirit of the World Data Center system developed to manage data resulting from the International Geophysical Year of 1957-58, the International Polar Year 2007-2009 (IPY) resulted in significant progress towards establishing an international polar data management network. However, a sustained international network is still evolving. In this paper we argue that the fundamental building blocks for such a network exist and that the time is right to move forward. We focus on the Arctic component of such a network with linkages to Antarctic network building activities. A review of an important set of Network building blocks is presented: i) the legacy of the IPY data and information service; ii) global data management services with a polar component (e.g. World Data System); iii) regional systems (e.g. Arctic Observing Viewer; iv) nationally focused programs (e.g. Arctic Observing Viewer, Advanced Cooperative Arctic Data and Information Service, Polar Data Catalogue, Inuit Knowledge Centre); v) programs focused on the local (e.g. Exchange for Local Observations and Knowledge of the Arctic, Geomatics and Cartographic Research Centre). We discuss current activities and results with respect to three priority areas needed to establish a strong and effective Network. First, a summary of network building activities reports on a series of productive meetings, including the Arctic Observing Summit and the Polar Data Forum, that have resulted in a core set of Network nodes and participants and a refined vision for the Network. Second, we recognize that interoperability for information sharing fundamentally relies on the creation and adoption of community-based data description standards and data delivery mechanisms. There is a broad range of interoperability frameworks and specifications available; however, these need to be adapted for polar community needs. Progress towards Network interoperability is reviewed, and a prototype distributed data systems is demonstrated. We

  20. International Polar Year (IPY): Thinking Beyond Polar Bears and Penguins

    NASA Astrophysics Data System (ADS)

    Morris, P. A.; Reiff, P.; Austin, S.; Johnson, L.; Walter, D.

    2008-12-01

    The mention of an International Polar Year (IPY) to most of our university students evokes images of polar bears, penguins, perhaps some concepts of polar exploration in previous centuries. IPY provides an unusual opportunity to incorporate various aspects of polar research into the classroom, research opportunities as well as outreach activities. The subject areas that can be incorporated into classroom and undergraduate research activities would include astrobiology, atmospheric sciences, glaciation past and present. Astrobiology, in particular geomicrobiology in relation to the pursuit of life on other planets, is dependent on an understanding of extremophile organisms and the identifying signatures that can be chemical or morphological. Atmospheric studies using balloons with attached instruments enable us to understand the role of an atmosphere in providing a habitable world and filtering damaging rays from the Sun. L. Agassiz studied the patterns of glaciation and their alteration of the crustal surface today and the information enabled us to identify similar patterns in Earth's past and today are important for identifying polar glaciation on Mars. The wide variation of scientific opportunities and research information are also important for developing partnership and outreach programs whether elements are used for planetarium shows, exhibits at museums, hands-on activities, or leading students to pursue atmospheric studies. Each and every one of the components provides different avenues and the potential partnerships are limited only by one's creativity. One example of an effective partnership is the January NASA Space Day at the University of Texas at Brownsville, Texas. The event reaches over 600 primarily Hispanic students from the entire Rio Grande Valley. In January, 2009, the topic will be IPY and the popular Polar Palooza. The event will include exhibits, talks, and the new planetarium show Ice Worlds. The partners for this event include Johnson Space

  1. Gravity wave activity during stratospheric sudden warmings in the 2007-2008 Northern Hemisphere winter

    NASA Astrophysics Data System (ADS)

    Wang, Ling; Alexander, M. Joan

    2009-09-01

    We use temperature retrievals from the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC)/Formosa Satellite Mission 3 (FORMOSAT-3) and Challenging Minisatellite Payload (CHAMP) Global Positioning Satellite (GPS) radio occultation profiles and independent temperature retrievals from the EOS satellite High Resolution Dynamics Limb Sounder (HIRDLS) and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) aboard the TIMED satellite to investigate stratospheric sudden warming (SSW) events and the accompanying gravity wave (GW) temperature amplitudes in the 2007-2008 Northern Hemisphere winter. We identify four SSW events (including a major one) occurring from late January to late February in 2008. We detect enhanced GW amplitudes in the stratosphere and subdued GW amplitudes in the lower mesosphere during the warming events. The timing of GW enhancement/suppression and warming/cooling events was generally close (within a couple days). We also find that stratospheric GW amplitudes were generally larger at the polar vortex edge and smaller in the vortex core and outside of the vortex and that stratospheric GW amplitudes were generally small over the North Pacific. Using a simplified GW dispersion relation and a GW ray-tracing experiment, we demonstrate that the enhanced GW amplitudes in the stratosphere during SSWs could be explained largely by GW propagation considerations. The existence of GW critical levels (the level at which the background wind is the same as the GW phase speed) near the stratopause during SSWs would block propagation of GWs into the mesosphere and thus could lead to the observed subdued GW activity in the lower mesosphere. Since this is the first study to analyze the COSMIC and CHAMP GPS temperature retrievals up to 60 km in altitude, we compare the GPS analysis with those from HIRDLS and SABER measurements. We find that the temporal variability of zonal mean temperatures derived from the GPS data is

  2. International Polar Year Youth Steering Committee

    NASA Astrophysics Data System (ADS)

    Baeseman, J. L.; Church, A.; Kuhn, T.; Raymond, M.; Lantuit, H.

    2006-12-01

    The International Youth Steering Committee is made up of youth representatives from around the world, from science, social science, aboriginal and arts backgrounds and ranging in education from new faculty to high school. The YSC serves as a voice for youth on polar issues and empower youth to get involved in issues facing the Polar Regions. YSC is working to draw the World's attention to the poles and act as a force for positive change. An International YSC website has been developed which will provide a forum where youth will be able to communicate with each other globally and get involved in IPY and YSC programs. One of these programs is the International Youth Conference on the Poles (IYCP). This conference, which will take place in May 2008, will bring together youth from around the world to focus on polar issues. Young polar researchers are being recruited to design educational materials based on their work for another YSC project, Polar Contests. YSC has partnered with Students on Ice (SOI), a non-profit organization who will be providing a series of nine SOI- IPY YSC expeditions to the Arctic and Antarctic over the course of IPY, allowing hundreds of students from around the world to experience the Polar Regions first-hand, learn from experts working in these areas and become inspired to work for their continued protection. We are also sponsoring an opportunity for youth from around the world to connect with and interview the participants of the International Geophysical Year (IGY), the results of that will ultimately be presented in book or documentary form at the close of IPY. The YSC has partnered with the science fiction educational book series, Tales of the Wonder Zone, to release Polaris; A Celebration of Polar Science, in which youth and professional authors from around the world submitted stories based on an IPY fifty years in the future. The final part of the YSC is to provide a forum and activities that will allow early career scientists to

  3. Leveraging the International Polar Year Legacy: Providing Historical Perspective for IPY Education, Outreach and Communication Efforts

    NASA Astrophysics Data System (ADS)

    Tsukernik, M.; McCaffrey, M. S.

    2006-12-01

    As the International Polar Year 2007-2008 (IPY) is fast approaching, it is important to look back and learn from the previous experience. Over 125 years ago, when an Austrian explorer and naval officer Lt. Karl Weyprecht called for an international yearlong intensive effort to study the Polar Regions, he probably never imagined that his model for international collaboration would become so widely popular. Frustrated by the lack of coordinated, international collaboration in research activities, Weyprecht proposed an intensive burst of research activity over the course of at least a year. The first IPY began in 1882 with 12 nations establishing 13 stations in the Arctic and 2 in the Southern Hemisphere. The initial yearlong plan did not go beyond data collection. However, the idea lived in the minds of scientists worldwide and the second IPY followed the first one 50 years later. By 1932, technology evolved significantly, and on top of ground-based meteorological and geophysical measurements, data collection also included radiosonde and acoustic atmospheric measurements. Occurring during a global economic depression, and between world wars, the second IPY faced many challenges. However, 40 permanent stations were established, some of which are still active. Scientific exploration also reached remote frontiers from Antarctica to the Earth's ionosphere. Less than a decade after the WWII, the idea of the next IPY started to circulate in scientific circles. The world was focused on space exploration and the word "polar" seemed too narrow for the gigantic projects planned for the 1957. That is why the initial idea of the third IPY evolved into the International Geophysical Year (IGY), although polar regions were still a major focus. The success of the IGY is almost overwhelming the first Earth orbiting satellites, a traverse of Antarctica, a discovery of the Radiation Belt, a series of science education films about IGY activities and research themes are just a few

  4. Activity of telavancin and comparator antimicrobial agents tested against Staphylococcus spp. isolated from hospitalised patients in Europe (2007-2008).

    PubMed

    Mendes, Rodrigo E; Sader, Helio S; Jones, Ronald N

    2010-10-01

    The activity of telavancin was evaluated against Staphylococcus spp. collected from European hospitals as part of an international surveillance study (2007-2008). A total of 7534 staphylococcal clinical isolates [5726 Staphylococcus aureus and 1808 coagulase-negative staphylococci (CoNS)] were included. Isolates were tested for susceptibility according to reference methods and minimum inhibitory concentration (MIC) values were interpreted based on Clinical and Laboratory Standards Institute (CLSI) 2010 and European Committee on Antimicrobial Susceptibility Testing (EUCAST) 2009 criteria. Telavancin breakpoints approved by the US Food and Drug Administration (FDA) were applied. Telavancin activity was evaluated against meticillin-resistant S. aureus (MRSA) displaying several antibiogram resistance patterns, including multidrug-resistant isolates. Telavancin was active against S. aureus [MIC(50/90) values (MICs for 50% and 90% of the isolates, respectively)=0.12/0.25mg/L; 100.0% susceptible] and CoNS (MIC(50/90)=0.12/0.25mg/L), inhibiting all isolates at < or =0.5mg/L. Similar results were observed when S. aureus were stratified by year or country of origin (MIC(50/90)=0.12/0.25mg/L). When MRSA isolates were clustered according to 48 different resistance patterns, telavancin showed consistent MIC(90) values (0.25mg/L) regardless of multidrug resistance. Amongst CoNS, telavancin was slightly more active against Staphylococcus capitis, Staphylococcus epidermidis, Staphylococcus hominis, Staphylococcus lugdunensis and Staphylococcus xylosus (MIC(50)=0.12 mg/L) compared with Staphylococcus haemolyticus, Staphylococcus saprophyticus and Staphylococcus warneri (MIC(50)=0.25mg/L). Overall, telavancin exhibited MIC(90) results two- to eight-fold lower than comparators (daptomycin, quinupristin/dalfopristin, vancomycin and linezolid). Based upon MIC(90) values, telavancin demonstrated potent in vitro activity against a contemporary (2007-2008) collection of Staphylococcus spp

  5. L'apparizione di Marte 2007-2008: il volto mutevole del pianeta

    NASA Astrophysics Data System (ADS)

    Tanga, P.

    2010-02-01

    Results of visual observations and CCD imaging of Mars during the 2007-2008 are presented. The aspect of the planet was greatly influenced by an encircling dust storm starting in June 2007. The atmosphere remained dusty for several months, lowering the contrast of albedo markings. The albedo spots themselves have been modified on a large scale, producing the most relevant surface changes of the last apparitions.

  6. International Polar Orbiter Processing Package (IPOPP)

    NASA Astrophysics Data System (ADS)

    Overton, J.; Fesenger, G.; Reed, B.; Thomas, W.

    2009-12-01

    In 1994, the United States merged its two polar-orbiting operational environmental satellite programs operated by the Department of Commerce and the Department of Defense respectively into a single system which is called the National Polar-orbiting Operational Environmental Satellite System (NPOESS). NPOESS is a tri-agency program comprised of the Department of Defense, the Department of Commerce and the National Aeronautics and Space Administration. NPOESS is managed by the Integrated Program Office (IPO) that is staffed by personnel from the three sponsoring agencies. The IPO is working with prime contractor Northrop Grumman Aerospace Systems (NGAS) and its subcontractors to develop, launch, and operate NPOESS. The first NPOESS satellite which is planned for 2013 will be preceded by a risk reduction mission named the NPOESS Preparatory Project (NPP) that is planned for launch in 2010. The International Polar Orbiter Processing Package (IPOPP) is a software package that will enable the Direct Readout user community to smoothly transition from the Earth Observing System (EOS) to the NPOESS. IPOPP will host US Government sanctioned algorithms that will enable the Direct Broadcast (DB) community to process, visualize, and evaluate Polar Orbiter Sensor and Environmental Data Records (starting with the Moderate Resolution Imaging Spectroradiometer (MODIS) and the NPP missions). The IPOPP development approach is to start with a framework that uses a Science Processing Algorithm (SPA) wrapping technique that allows a modular implementation to envelop sensor unique algorithms thus making IPOPP a multi-mission processing package. As a multi-platform processing package, IPOPP will meet the high expectations of the Direct Broadcast community for mission continuity from EOS to NPOESS, enable a global feedback loop for NPP Cal/Val campaigns, and initiate the role of the research to operations provider for the Direct Readout Mission.

  7. International Polar Year Observations From the International Space Station

    NASA Technical Reports Server (NTRS)

    Pettit, Donald R.; Runco, Susan; Byrne, Gregory; Willis, Kim; Heydorn, James; Stefanov, William L.; Wilkinson, M. Justin; Trenchard, Michael

    2006-01-01

    Astronauts aboard the International Space Station (ISS) have several opportunities each day to observe and document high-latitude phenomena. Although lighting conditions, ground track and other viewing parameters change with orbital precessions and season, the 51.6 degree orbital inclination and 400 km altitude of the ISS provide the crew an excellent vantage point for collecting image-based data for IPY investigators. To date, the database of imagery acquired by the Crew Earth Observations (CEO) experiment aboard the ISS (http://eol.jsc.nasa.gov) contains more than 12,000 images of high latitude (above 50 degrees) events such as aurora, mesospheric clouds, sea-ice, high-latitude plankton blooms, volcanic eruptions, and snow cover. The ISS Program will formally participate in IPY through an activity coordinated through CEO entitled Synchronized Observations of Polar Mesospheric Clouds, Aurora and Other Large-scale Polar Phenomena from the ISS and Ground Sites. The activity will augment the existing collection of Earth images taken from the ISS by focusing astronaut observations on polar phenomena. NASA s CEO experiment will solicit requests by IPY investigators for ISS observations that are coordinated with or complement ground-based polar studies. The CEO imagery website (http://eol.jsc.nasa.gov) will provide an on-line form for IPY investigators to interact with CEO scientists and define their imagery requests. This information will be integrated into daily communications with the ISS crews about their Earth Observations targets. All data collected will be cataloged and posted on the website for downloading and assimilation into IPY projects.

  8. In situ Observations of CIRs on STEREO, Wind, and ACE During 2007 - 2008

    NASA Astrophysics Data System (ADS)

    Mason, G. M.; Desai, M. I.; Mall, U.; Korth, A.; Bucik, R.; von Rosenvinge, T. T.; Simunac, K. D.

    2009-05-01

    During the 2007 and 2008 solar minimum period, STEREO, Wind, and ACE observed numerous Corotating Interaction Regions (CIRs) over spatial separations that began with all the spacecraft close to Earth, through STEREO separation angles of ˜ 80 degrees in the fall of 2008. Over 35 CIR events were of sufficient intensity to allow measurement of He and heavy ion spectra using the IMPACT/SIT, EPACT/STEP and ACE/ULEIS instruments on STEREO, Wind, and ACE, respectively. In addition to differences between the spacecraft expected on the basis of simple corotation, we observed several events where there were markedly different time-intensity profiles from one spacecraft to the next. By comparing the energetic particle intensities and spectral shapes along with solar wind speed we examine the extent to which these differences are due to temporal evolution of the CIR or due to variations in connection to a relatively stable interaction region. Comparing CIRs in the 1996 - 1997 solar minimum period vs. 2007 - 2008, we find that the 2007 - 2008 period had many more CIRs, reflecting the presence of more high-speed solar wind streams, whereas 1997 had almost no CIR activity.

  9. The First International Conference on Mars Polar Science and Exploration

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This volume contains abstracts of articles that have been accepted for presentation at the First International Conference on Mars Polar Science and Exploration. Articles about the geology of the Martian Polar regions were presented, and analogs from Earth's geology were also presented. Presentations also were given about the probable contents of the Martian polar caps

  10. Education and outreach for the International Polar Year

    NASA Astrophysics Data System (ADS)

    Pfirman, Stephanie; Bell, Robin Elizabeth; Turrin, Margie; Maru, Poonam

    2004-12-01

    If the 65 educators, scientists, and media specialists who gathered at the “Bridging the Poles” workshop in Washington, D.C. last June have their way a semitrailer truck labeled “Got Snow?” would traverse the country during the International Polar Year (IPY) of 2007-2009 loaded with polar gear, interactive activities, and a snowmaker. We would significantly increase the number of Arctic residents—especially indigenous Alaskans—with Ph.D.s. We would build exchange programs between inner city youths and polar residents. Polar exhibitions would open at natural history and art museums and zoos. And polar postage stamps, interactive polar computer games, national polar book-of-the-month recommendations, made-for-TV polar documentaries, and a polar youth forum would bring the poles front and center to the public's attention.

  11. The Development of Interconnection Standards in Six States In 2007-2008

    SciTech Connect

    Keyes, Jason B.

    2008-05-01

    This paper discusses the process of developing standards for the interconnection of photovoltaic systems and other generators under ten megawatts to the electric grid. State utility commission rulemakings in 2007-2008 in Florida, New Mexico, North Carolina, Maryland, Illinois and Utah provide the basis for analysis of what is and should be considered in the development of standards, and how the process can be improved. State interconnection standards vary substantially, and many utilities have discretion to establish additional or different requirements, creating literally hundreds of sets of rules. This lack of uniformity imposes a significant cost on project developers and installers to track and comply with applicable rules. As well, burdensome provisions and uncertain costs and timelines present formidable barriers to entry, which advocates have limited resources to challenge. For a better process, the author proposes: establishing federal standards as a baseline, involving solar advocates, and developing a utility cost-recovery mechanism.

  12. International Student Guide to U.S. Community Colleges, 2007-2008

    ERIC Educational Resources Information Center

    American Association of Community Colleges (NJ1), 2007

    2007-01-01

    This guide was produced for prospective students considering studying in the United States. The guide is organized to help students through all stages of the process, including learning about the U.S. higher education system, finding the right college, benefits of attending community college, obtaining a student visa, estimating expenses, living…

  13. IPY 2007-2008 and Scientists, Science Organisations, and the Public

    NASA Astrophysics Data System (ADS)

    Carlson, D. J.

    2006-12-01

    An initial burst of enthusiasm resulted in more than 1000 expressions of interest and nearly 500 internationally coordinated proposals for polar research during IPY. An international committee has endorsed more than 200 of these proposals, and most other proposals and nearly all expressions of interest have found ways to join the endorsed programme. Ten nations have announced new IPY science funding totalling in excess of 300M USD for the two years of operations; several nations will make announcements soon. Most on-going funding for polar research, coming from at least 30 nations, approximately 1.6B USD over two years, will also support IPY activities. What should the thousands of scientists hoping to participate expect, personally and collectively? What should the overall science entity expect, during and after IPY? And, finally, what should the public expect, after much attention and the expenditure of 2B USD, not to mention the on-going and future costs of ice breakers and ice-monitoring satellites and polar bases? Many IPY scientists will initially experience disappointment. Funding, even with IPY infusions, will fall short of need, and initial proposal success rates will stay below 50% in almost every nation, far below in some nations. In many nations, however, a catch-up effect will occur, leading to more funds in 2008 or 2009 than in 2006 and 2007. A step-up effect will also occur, leading to increased on-going funds for polar research, although perhaps in smaller steps and in fewer countries than we might hope. Scientists should expect increased public attention to their work and increased demand for their cooperation and contribution to international data management and to public outreach. Individually and collectively, IPY scientists have the opportunity to interact with an amazing array of fellow scientists, exchanging experience and enthusiasm on topics from gravitational variations to genomic sequences to Gwich'in cultures. Science as an entity will

  14. Uses of Formal and Informal Assessments of English Language Learners in a Language Experience Class, School Year 2007-2008

    ERIC Educational Resources Information Center

    Montgomery, Joel R.

    2008-01-01

    This paper will compare the uses of selected formal and informal assessments of English language learners (ELLs) in the Language Experience class [TRANSLANGEXP7(&8)-008] at Kimball Middle School, Illinois School District U-46, Elgin, Illinois, during school year 2007- 2008. See figure 1 (page 14) for a graphic display of these assessments and…

  15. Examination of Case Law (2007-2008) regarding Autism Spectrum Disorder and Violations of the Individuals with Disabilities Education Act

    ERIC Educational Resources Information Center

    Hill, Doris Adams

    2009-01-01

    Ninety-nine court cases from the "LexisNexis" database regarding students, ages 3-21, with various forms of Autism Spectrum Disorder (ASD) were examined for the years 2007-2008. Procedural and substantive violations to the Individuals with Disabilities Education Act (IDEA) and the provision of a Free and Appropriate Public Education (FAPE) were…

  16. NASA Battery Working Group - 2007-2008: Battery Task Summary Report

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle

    2008-01-01

    This presentation provides a summary of the 2007-2008 NASA Battery Working Group efforts completed in support of the NASA Engineering Safety Center (NESC). The effort covered a series of pro-active tasks that address the following: Binding Procurements -- guidelines related to requirements for the battery system that should be considered at the time of contract award Wet Life of Ni-H2 Batteries -- issues/strategies for effective storage and impact of long-term storage on performance and life Generic Guidelines for Lithium-ion Safety, Handling and Qualification -- Standardized approaches developed and risk assessments (1) Lithium-ion Performance Assessment -- survey of manufacturers and capabilities to meet mission needs. Guidelines document generated (2) Conditions Required for using Pouch Cells in Aerospace Missions -- focus on corrosion, thermal excursions and long-term performance issues. Document defining requirements to maintain performance and life (3) High Voltage Risk Assessment -- focus on safety and abuse tolerance of battery module assemblies. Recommendations of features required for safe implementation (4) Procedure for Determination of Safe Charge Rates -- evaluation of various cell chemistries and recommendation of safe operating regimes for specific cell designs

  17. Multifractal analysis of Asian markets during 2007-2008 financial crisis

    NASA Astrophysics Data System (ADS)

    Hasan, Rashid; Mohammad, Salim M.

    2015-02-01

    2007-2008 US financial crisis adversely affected the stock markets all over the world. Asian markets also came under pressure and were differently affected. As markets under stress could reveal features that remain hidden under normal conditions, we use MF-DFA technique to investigate the multifractal structure of the US and seven Asian stock markets during the crisis period. The overall period of study, from 01 July 2002 to 31 December 2013, is divided into three sub-periods: pre-crisis period, crisis period and post-crisis period. We find during the crisis period markets of the US, Japan, Hong Kong, S. Korea and Indonesia show very strong non-linearity for positive values of the moment q. We calculate the singularity spectra, f(α) for the three sub-periods for all markets. During the crisis period, we observe that the peaks of the f(α) spectra shift to lower values of α and markets of the US, Japan, Hong Kong, Korea and Indonesia exhibit increased long range correlations of large fluctuations in index returns. We also study the impact of the crisis on the power law exponent in the tail region of the cumulative return distribution and find that by excluding the crisis period from the overall data sets, the tail exponent increases across all markets.

  18. Toward an International Lunar Polar Volatiles Strategy

    NASA Technical Reports Server (NTRS)

    Gruener, J. E.; Suzuki, N. H.; Carpenter, J. D.

    2015-01-01

    Fourteen international space agencies are participating in the International Space Exploration Coordination Group (ISECG), working together to advance a long-range human space exploration strategy. The ISECG is a voluntary, non-binding international coordination mechanism through which individual agencies may exchange information regarding interests, objectives, and plans in space exploration with the goal of strengthening both individual exploration programs as well as the collective effort. The ISECG has developed a Global Exploration Roadmap (GER) that reflects the coordinated international dialog and continued preparation for exploration beyond low-Earth orbit - beginning with the Moon and cis-lunar space, and continuing to near-Earth asteroids, and Mars. Space agencies agree that human space exploration will be most successful as an international endeavor, given the challenges of these missions. The roadmap demonstrates how initial capabilities can enable a variety of missions in the lunar vicinity, responding to individual and common goals and objectives, while contributing to building partnerships required for sustainable human space exploration that delivers value to the public.

  19. Civil unrest and birthweight: an exploratory analysis of the 2007/2008 Kenyan Crisis.

    PubMed

    Bell, Suzanne; Prata, Ndola; Lahiff, Maureen; Eskenazi, Brenda

    2012-05-01

    For decades, Africa has been plagued by political and ethnic conflict, the health ramifications of which are often not investigated. A crisis occurred recently in Kenya following the 2007 presidential election. Ethnic violence ensued, targeting the incumbent President Kibaki's Kikuyu people. The violence occurred primarily in Nairobi and the Rift Valley of Kenya. We sought to examine the association between exposure to the 2007/2008 Kenyan Crisis and birthweight. Using the 2008/2009 Kenyan Demographic and Health Survey (KDHS), we compared birthweights of infants in utero or not yet conceived during the 15 months after the political turmoil following the 2007 presidential election (exposed) to those who were born before the crisis (unexposed). There were 663 "exposed" and 687 "unexposed" infants. Multivariate regression was used. We examined the possibility of two-way and three-way interactions between exposure status, ethnicity (Kikuyu versus non-Kikuyu), and region (violent region versus not). Overall, exposure to the Kenyan Crisis was associated with lower birthweight. Kikuyu women living in a violent region who were exposed during their 2nd trimester had the greatest difference in birthweight in comparison to all unexposed infants: 564.4g lower (95% CI 285.1, 843.6). Infants of Kikuyu exposed during the 2nd trimester and living in a violent region weighed 603.6g less (95% CI 333.6, 873.6) than Kikuyu infants born during the unexposed period. Political unrest may have implications for the birthweight of infants, particularly among targeted populations. Given the adverse sequelae associated with lowered birthweight, these results suggest that particular attention should be paid to pregnant women and targeted ethnic groups following such events. PMID:22410269

  20. Monitoring the Migrations of Wild Snake River Spring/Summer Chinook Salmon Juveniles, 2007-2008

    SciTech Connect

    Achord, Stephen; Sandford, Benjamin P.; Hockersmith, Eric E.

    2009-07-09

    This report provides results from an ongoing project to monitor the migration behavior and survival of wild juvenile spring/summer Chinook salmon in the Snake River Basin. Data reported is from detections of PIT tagged fish during late summer 2007 through mid-2008. Fish were tagged in summer 2007 by the National Marine Fisheries Service (NMFS) in Idaho and by the Oregon Department of Fish and Wildlife (ODFW) in Oregon. Our analyses include migration behavior and estimated survival of fish at instream PIT-tag monitors and arrival timing and estimated survival to Lower Granite Dam. Principal results from tagging and interrogation during 2007-2008 are: (1) In July and August 2007, we PIT tagged and released 7,390 wild Chinook salmon parr in 12 Idaho streams or sample areas. (2) Overall observed mortality from collection, handling, tagging, and after a 24-hour holding period was 1.4%. (3) Of the 2,524 Chinook salmon parr PIT tagged and released in Valley Creek in summer 2007, 218 (8.6%) were detected at two instream PIT-tag monitoring systems in lower Valley Creek from late summer 2007 to the following spring 2008. Of these, 71.6% were detected in late summer/fall, 11.9% in winter, and 16.5% in spring. Estimated parr-to-smolt survival to Lower Granite Dam was 15.5% for the late summer/fall group, 48.0% for the winter group, and 58.5% for the spring group. Based on detections at downstream dams, the overall efficiency of VC1 (upper) or VC2 (lower) Valley Creek monitors for detecting these fish was 21.1%. Using this VC1 or VC2 efficiency, an estimated 40.8% of all summer-tagged parr survived to move out of Valley Creek, and their estimated survival from that point to Lower Granite Dam was 26.5%. Overall estimated parr-to-smolt survival for all summer-tagged parr from this stream at the dam was 12.1%. Development and improvement of instream PIT-tag monitoring systems continued throughout 2007 and 2008. (4) Testing of PIT-tag antennas in lower Big Creek during 2007-2008

  1. Second International Conference on Mars Polar Science and Exploration

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This volume contains abstracts that were presented at the Second International Conference on Mars Polar Science and Exploration, August 21-25, 2000. The abstracts of the presentations given are listed. Presentations were given on the advances in technology, data analysis of past and current missions, and new instruments destined for Mars. Particular attention was paid to the polar regions and what they reveal about Mars.

  2. Control of polarization effects by internal antireflection.

    PubMed

    Knittl, Z

    1981-01-01

    Mouchart's theory of the buffer layer is reformulated in terms of internal antireflection and extended to general dielectric/metallic media. The all-dielectric case is then studied in oblique incidence as a means of depolarizing partial reflectors. Several procedures are indicated for the construction of buffering stacks which, when coupled with germinal stacks, balance out their p and s reflections at the given level. Examples of depolarized half-mirrors are presented. A novel version of the Argand diagram for thin films in oblique incidence is introduced during the analysis. PMID:20309073

  3. The International Space Station Supports International Polar Year (IPY)

    NASA Technical Reports Server (NTRS)

    Evans, Cynthia A.; Pettit, Donald R.

    2007-01-01

    Every day, ISS astronauts photograph designated sites and dynamic events on the Earth's surface using digital cameras equipped with a variety of lenses. Depending on observation parameters, astronauts can collect high resolution (4-6 m pixel size) or synoptic views (lower resolution but covering very large areas) digital data in 3 (red-green-blue) color bands. ISS crews have daily opportunities to document a variety of high-latitude phenomena. Although lighting conditions, ground track and other viewing parameters change with orbital precessions and season, the 51.6o orbital inclination and 400 km altitude of the ISS provide the crew an unique vantage point for collecting image-based data of polar phenomena, including surface observations to roughly 65o latitude, and upper atmospheric observations that reach nearly to the poles. During the 2007-2009 timeframe of the IPY, polar observations will become a scientific focus for the CEO experiment; the experiment is designated ISS-IPY. We solicit requests from scientists for observations from the ISS that are coordinated with or complement ground-based polar studies. The CEO imagery website for ISS-IPY provides an on-line form that allows IPY investigators to interact with CEO scientists and define their imagery requests. This information is integrated into daily communications with the ISS astronauts about their Earth Observations targets. All data collected are cataloged and posted on the website for downloading and assimilation into IPY projects. Examples of imagery and detailed information about scientific observations from the ISS can also be downloaded from the ISS-IPY web site.

  4. Cryosphere Communication from Knowledge to Action: Polar Educators International

    NASA Astrophysics Data System (ADS)

    Crowley, S.

    2012-12-01

    Evidence from the recent IPY meetings shows that education and outreach of the 2007-08 IPY touched 24 million people; we intend to grow that number. As a legacy of IPY and as a direct action of IPY Montreal, we announced the establishment of Polar Educators International - a global professional network for those that educate in, for, and about the Polar Regions. We intend to move polar science forward by connecting the cultures and enthusiasm of polar education across the globe. The founding members come from polar and non-polar nations around the world. The new group draws together museums, schools, universities, science centers, formal and informal education, expeditions, NGOs, companies, governmental organizations, and non-profits. Working across national, disciplinary, and age group boundaries, we want to improve polar science & education for the next generation of policy makers, entrepreneurs, explorers, citizen scientists, journalists and educators; as well as the the public. The new network of more than 200 leading educators, scientists, and community members will develop innovative resources to communicate polar science. We intend to engage those learning and teaching about the polar regions, and thereby change the terms of debate, and the framework of education to rekindle student and public engagement with global environmental changes. We are committed to engaging our membership and have clear directions from our recent survey and report from the community. This presentation will address the needs put forth from our membership and where the organization will go in the future to inform a professional network on science and outreach in the polar regions.

  5. Laser-driven polarized hydrogen and deuterium internal targets

    SciTech Connect

    Jones, C.E.; Fedchak, J.A.; Kowalczyk, R.S.

    1995-08-01

    After completing comprehensive tests of the performance of the source with both hydrogen and deuterium gas, we began tests of a realistic polarized deuterium internal target. These tests involve characterizing the atomic polarization and dissociation fraction of atoms in a storage cell as a function of flow and magnetic field, and making direct measurements of the average nuclear tensor polarization of deuterium atoms in the storage cell. Transfer of polarization from the atomic electron to the nucleus as a result of D-D spin-exchange collisions was observed in deuterium, verifying calculations suggesting that high vector polarization in both hydrogen and deuterium can be obtained in a gas in spin temperature equilibrium without inducing RF transitions between the magnetic substates. In order to improve the durability of the system, the source glassware was redesigned to simplify construction and installation and eliminate stress points that led to frequent breakage. Improvements made to the nuclear polarimeter, which used the low energy {sup 3}H(d,n){sup 4}He reaction to analyze the tensor polarization of the deuterium, included installing acceleration lenses constructed of wire mesh to improve pumping conductance, construction of a new holding field coil, and elimination of the Wien filter from the setup. These changes substantially simplified operation of the polarimeter and should have reduced depolarization in collisions with the wall. However, when a number of tests failed to show an improvement of the nuclear polarization, it was discovered that extended operation of the system with a section of teflon as a getter for potassium caused the dissociation fraction to decline with time under realistic operating conditions, suggesting that teflon may not be a suitable material to eliminate potassium from the target. We are replacing the teflon surfaces with drifilm-coated ones and plan to continue tests of the polarized internal target in this configuration.

  6. Observing the Polar Regions from Space: Educational Opportunities for an International Polar Year and International Heliophysical Year

    NASA Astrophysics Data System (ADS)

    Kelley, J.; Prakash, A.; Yanow, G.; Gens, R.; Johnson, L.

    2004-12-01

    The International Polar Year (IPY) and the International Heliophysical Year (IHY) will require integrated circumpolar research projects using present and advanced technologies. The IPY/IHY will offer exceptional opportunities for participation world-wide and especially by indigenous residents of the Arctic. Educational outreach will be an essential component of these programs. Participation in IPY/IHY projects and utilization of educational products will improve science competence and citizen awareness of the importance of the polar regions. An important and practical objective of IPY and IHY educational outreach is to recognize that the earth is a system and that it is best to acquire seasonal and secular atmospheric, terrestrial and oceanic environmental data from space. Acquisition of reliable ground truth data in support of remote sensing of geophysical and geochemical variables will be essential, especially with broad long-term coverage in the polar regions. In the United States NASA has developed a strategy for long-term monitoring of some key parameters needed to bring us closer to the answers we need regarding climate change and its relation to social systems. This technology consists of a group of six satellites that can make a suite of earth observations referred to as the "A Train". Data from this group of polar orbiting satellites, as well as from the Orbital Carbon Observatory (OCO), and older Quikscat and new Seawinds radar missions, will provide focus for an education program based not only on the acquisition of polar data but also on how these data correlate with global observations. Use of new technology to make data accessible to all users will be an important outcome of the International Polar Year and International Heliophysical Year.

  7. Earth Science Teaching Strategies Used in the International Polar Year

    NASA Astrophysics Data System (ADS)

    Sparrow, E. B.

    2009-04-01

    There are many effective methods for teaching earth science education that are being successfully used during the fourth International Polar Year (IPY). Relevance of IPY and the polar regions is better understood using a systems thinking approach used in earth science education. Changes in components of the earth system have a global effect; and changes in the polar regions will affect the rest of the world regions and vice versa. Teaching strategies successfully used for primary, secondary, undergraduate and graduate student earth science education and IPY education outreach include: 1) engaging students in earth science or environmental research relevant to their locale; 2) blending lectures with research expeditions or field studies, 3) connecting students with scientists in person and through audio and video conferencing; 4) combining science and arts in teaching, learning and communicating about earth science and the polar regions, capitalizing on the uniqueness of polar regions and its inhabitants, and its sensitivity to climate change; and 5) integrating different perspectives: western science, indigenous and community knowledge in the content and method of delivery. Use of these strategies are exemplified in IPY projects in the University of the Arctic IPY Higher Education Outreach Project cluster such as the GLOBE Seasons and Biomes project, the Ice Mysteries e-Polar Books: An Innovative Way of Combining Science and Literacy project, the Resilience and Adaptation Integrative Graduate Education and Research Traineeship project, and the Svalbard Research Experience for Undergraduates project.

  8. Springtime Observations of Black Carbon in Arctic Snow across Northern Russia During IPY 2007-2008

    NASA Astrophysics Data System (ADS)

    Grenfell, T. C.; Warren, S. G.; Radionov, V. F.; Kogan, S. E.

    2008-12-01

    Black carbon (BC) in snow at ppb levels can significantly reduce the visible and near IR albedo. The effect is important for climate in regions where large areas of snow-covered surfaces are exposed to significant sunlight. The initial study of Clarke and Noone (1985) across the western Arctic in 1983-84 indicated albedo reduction of about 0-4 percent due to BC; however, their survey did not include results from the Russian Arctic. During April and May of 2007 and 2008, as part of the International Polar Year Program, two cooperative U.S.-Russian expeditions obtained the first set of BC observations at selected sites near the communities of Naryan Mar, Vorkuta, Dikson, Khatanga, Tiksi, Chersky, Bilibino, and Pevek, spanning almost the entire northern coastal zone of Russia. Samples were also obtained near Yakutsk, a sub-Arctic region of boreal forest with a severe winter climate. This time period was chosen to provide access to the full winter snowpack just prior to the onset of spring melt. This project is a critical component of a repeat and extension of the original 1985 survey, which now includes sites spanning the entire Arctic. A discussion of this work is the topic of an invited presentation by S. G. Warren in session "Snow and Ice Impurities as Climate Forcing Agents and Records" (C04). This project required access to restricted border regions of Russia, which was facilitated by the political prominence of the IPY program in the Russian government. Generous logistical assistance and advice were provided by Dr. V. N. Makarov of the Permafrost Institute in Yakutsk, Dr. Sergei Zimov of the Northeast Scientific Station at Chersky, and the Hydrometeorological Service at Pevek. Commercial air travel to the above-mentioned communities, in conjunction with local transportation, provided access to the observation sites, which were located at distances of 15-100 km from local sources to sample background levels of BC. At each site, snow samples and density profiles

  9. CATACLYSMIC VARIABLES FROM THE SLOAN DIGITAL SKY SURVEY. VIII. THE FINAL YEAR (2007-2008)

    SciTech Connect

    Szkody, Paula; Anderson, Scott F.; Brooks, Keira; Kronberg, Martin; Riecken, Thomas; Gaensicke, Boris T.; Ross, Nicholas P.; Schmidt, Gary D.; Schneider, Donald P.; Agueeros, Marcel A.; Gomez-Moran, Ada N.; Schwope, Axel D.; Knapp, Gillian R.; Schreiber, Matthias R.

    2011-12-15

    This paper completes the series of cataclysmic variables (CVs) identified from the Sloan Digital Sky Survey (SDSS) I/II. The coordinates, magnitudes, and spectra of 33 CVs are presented. Among the 33 are eight systems known prior to SDSS (CT Ser, DO Leo, HK Leo, IR Com, V849 Her, V405 Peg, PG1230+226, and HS0943+1404), as well as nine objects recently found through various photometric surveys. Among the systems identified since the SDSS are two polar candidates, two intermediate polar candidates, and one candidate for containing a pulsating white dwarf. Our follow-up data have confirmed a polar candidate from Paper VII and determined tentative periods for three of the newly identified CVs. A complete summary table of the 285 CVs with spectra from SDSS I/II is presented as well as a link to an online table of all known CVs from both photometry and spectroscopy that will continue to be updated as future data appear.

  10. The Polarized Internal Target at ANKE: First Results

    SciTech Connect

    Grigoryev, K.; Mikirtytchiants, M.; Engels, R.; Lorentz, B.; Prasuhn, D.; Rathmann, F.; Sarkadi, J.; Seyfarth, H.; Stroeher, H.; Klehr, F.; Mikirtytchiants, S.; Vasilyev, A.

    2007-06-13

    For future few-nucleon interactions studies with polarized beams and targets at COSY-Juelich, a polarized internal storage cell gas target was implemented at the magnetic spectrometer ANKE in summer 2005. First commissioning of the polarized Atomic Beam Source (ABS) at ANKE was carried out and some improvements of the system have been done. At the same time, storage-cell tests to determine the COSY beam dimensions have been performed. In February 2005, a first storage cell prototype was implemented. It was made from an aluminum foil covered by a special PTFE suspension. In November 2005, tests were carried out with a storage cell using a polarized hydrogen beam from the ABS, electron cooling and stacking injection of the COSY beam at different deflection angles of the ANKE spectrometer magnet. An average target polarization of P=0.44{+-}0.03 (November 2005 beamtime) was measured, while we expected about P=0.51-0.55 due to the availability of rf-transition units in the ABS. The jet target thickness was measured as (1.5{+-}0.1){center_dot}1011 atoms/cm2. In March 2006, measurements with unpolarized protons at T=831 MeV and an unpolarized H2 beam injected from a gas feeding system into the aluminum storage cell were carried out. The analysis of the pp {yields} pp{pi}0 and pp {yields} pn{pi}+ reactions showed that events from the extended target can be clearly identified in the ANKE forward detector system.

  11. International Field School on Permafrost, Polar Urals, 2012

    NASA Astrophysics Data System (ADS)

    Streletskiy, D. A.; Grebenets, V.; Ivanov, M.; Sheinkman, V.; Shiklomanov, N. I.; Shmelev, D.

    2012-12-01

    The international field school on permafrost was held in the Polar Urals region from June, 30 to July 9, 2012 right after the Tenth International Conference on Permafrost which was held in Salekhard, Russia. The travel and accommodation support generously provided by government of Yamal-Nenets Autonomous Region allowed participation of 150 permafrost young research scientists, out of which 35 students from seven countries participated in the field school. The field school was organized under umbrella of International Permafrost Association and Permafrost Young Research Network. The students represented diverse educational backgrounds including hydrologists, engineers, geologists, soil scientists, geocryologists, glaciologists and geomorphologists. The base school camp was located near the Harp settlement in the vicinity of Polar Urals foothills. This unique location presented an opportunity to study a diversity of cryogenic processes and permafrost conditions characteristic for mountain and plain regions as well as transition between glacial and periglacial environments. A series of excursions was organized according to the following topics: structural geology of the Polar Urals and West Siberian Plain (Chromite mine "Centralnaya" and Core Storage in Labitnangy city); quaternary geomorphology (investigation of moraine complexes and glacial conditions of Ronamantikov and Topographov glaciers); principles of construction and maintains of structures built on permafrost (Labitnangy city and Obskaya-Bovanenkovo Railroad); methods of temperature and active-layer monitoring in tundra and forest-tundra; cryosols and soil formation in diverse landscape condition; periglacial geomorphology; types of ground ice, etc. Every evening students and professors gave a series of presentations on climate, vegetation, hydrology, soil conditions, permafrost and cryogenic processes of the region as well as on history, economic development, endogenous population of the Siberia and the

  12. Determinants of exposure to secondhand smoke among Vietnamese adults: California Vietnamese Adult Tobacco Use Survey, 2007-2008.

    PubMed

    Webber, Whitney L; van Erp, Brianna; Stoddard, Pamela; Tsoh, Janice Y

    2014-01-01

    Because smoking rates are high among Vietnamese men, we used data from the 2007-2008 California Vietnamese Adult Tobacco Use Survey to estimate secondhand smoke exposure and associated risk factors among Vietnamese nonsmokers. Thirty percent of nonsmokers were exposed to secondhand smoke (SHS) at home, 8% at work, 52% in bars, and 67% on a college campus. At home, odds of SHS exposure were greater for women than for men and for adults aged less than 40 years than for older adults. Odds of SHS exposure were higher for former smokers at work (among employed men) and among men when in bars. Future interventions should consider sex, age, and smoking history in efforts to prevent SHS exposure among Vietnamese adults. PMID:24831285

  13. The International Solar Polar Mission - A problem in constrained optimization

    NASA Technical Reports Server (NTRS)

    Sweetser, T. H., III; Parmenter, M. E.; Pojman, J. L.

    1981-01-01

    The International Solar Polar Mission is sponsored jointly by NASA and the European Space Agency to study the sun and the solar environment from a new vantage point. Trajectories far out of the ecliptic plane are achieved by a gravity assist from Jupiter which sends the spacecraft back over the poles of the sun. The process for optimizing these trajectories is described. From the point of view of trajectory design, performance is measured by the time spent at high heliographic latitudes, but many trajectory constraints must be met to ensure spacecraft integrity and good scientific return. The design problem is tractable by closely approximating integrated trajectories with specially calibrated conics. Then the optimum trajectory is found primarily by graphical methods, which were easy to develop and use and are highly adaptable to changes in the plan of the mission.

  14. Effects of Traditional and Nontraditional Forms of Parental Involvement on School-Level Achievement Outcome: An HLM Study Using SASS 2007-2008

    ERIC Educational Resources Information Center

    Shen, Jianping; Washington, Alandra L.; Bierlein Palmer, Louann; Xia, Jiangang

    2014-01-01

    The authors examined parental involvement's (PI) impact on school performance. The hierarchical linear modeling method was applied to national Schools and Staffing Survey 2007-2008 data. They found that PI variables explained significant variance for the outcomes of (a) meeting adequate yearly progress (AYP) and (b) being free from sanctions.…

  15. A Study of Support Services in Schools and Their Relationship with School Effectiveness in American Public Schools: Findings from the School and Staffing Survey (Sass) 2007-2008

    ERIC Educational Resources Information Center

    Gibbs, Diane J.

    2012-01-01

    This study inquires into support services in schools and their relationship to school effectiveness by using data from the National Center for Education Statistics 2007-2008 School and Staffing Survey (SASS). Students' ability to learn is impacted by their physical and mental health. It is more difficult to measure the influence of…

  16. Roles of regulated internalization in the polarization of cell surface receptors

    PubMed Central

    Tian, Wei; Cao, Youfang; Ismael, Amber; Stone, David

    2016-01-01

    Cell polarization, the generation of cellular asymmetries, is a fundamental biological process. Polarity of different molecules can arise through several mechanisms. Among these, internalization has been shown to play an important role in the polarization of cell surface receptors. The internalization of cell surface receptors can be upregulated upon ligand binding. Additional regulatory mechanism can downregulate the internalization process. Here we describe a general model, which incorporates these two opposing processes, to study the role of internalization in the establishment of cell polarity. We find that the competition between these two processes is sufficient to induce receptor polarization. Our results show that regulated internalization provides additional regulation on polarization as well. In addition, we discuss applications of our model to the yeast system, which shows the capability and potential of the model. PMID:25570171

  17. Ground and shipboard measurements of atmospheric gaseous elemental mercury over the Yellow Sea region during 2007-2008

    NASA Astrophysics Data System (ADS)

    Nguyen, Duc Luong; Kim, Jin Young; Shim, Shang-Gyoo; Zhang, Xiao-Shan

    2011-01-01

    The first ever shipboard measurements of atmospheric gaseous elemental mercury (GEM) over the Yellow Sea were carried out. Ground measurements were also performed at background and urban sites surrounding the Yellow Sea during 2007-2008. The GEM mean concentrations obtained from ground measurements at Ningbo, Chengshantou, and Deokjeok, and from shipboard measurements for the routes of Incheon-Qingdao, Incheon-Weihai, and Incheon-Jeju were 3.79 ± 1.29, 2.07 ± 0.91, 1.79 ± 0.80, 1.82 ± 0.51, 2.03 ± 0.66, and 2.43 ± 0.59 ng m -3, respectively. Compared with the GEM background concentration in the northern hemisphere, the slightly higher GEM regional background concentration of 2.08 ± 0.85 ng m -3 over the Yellow Sea region, based on shipboard measurements and ground measurements at background sites, gave implications for the impact of anthropogenic mercury sources surrounding the Yellow Sea. Shipboard measurements over the Yellow Sea showed a decrease of mercury concentration compared with aircraft measurements during ACE-ASIA campaign in 2001, though it was still generally higher than those from other seas or oceans around the world. The contrasting patterns in seasonal and diurnal variations of GEM concentration between background and urban sites were apparent due to the influence of different sources; for example, natural sources, such as vegetative and foliar emissions in background area, and local anthropogenic sources, such as coal combustion in urban area. The significantly elevated GEM concentrations at Deokjeok, a Korean background site, during the spring of 2008 were attributed to the long-range transport from the southern part of Liaoning province, one of the heaviest mercury-polluted areas in China.

  18. OBS records of Whale vocalizations from Lucky-strike segment of the Mid-Atlantic Ridge during 2007-2008

    NASA Astrophysics Data System (ADS)

    Chauhan, A.; Rai, A.; Singh, S. C.; Crawford, W. C.; Escartin, J.; Cannat, M.

    2009-12-01

    Passive seismic experiments to study seismicity require a long term deployment of ocean-bottom seismometers (OBSs). These instruments also record a large amount of non-seismogenic signals such as movement of large ships, air-gun shots, and marine mammal vocalizations. We report a bi-product of our passive seismic experiment (BBMOMAR) conducted around the Lucky-strike hydrothermal field of the slow-spreading mid-Atlantic ridge. Five multi-component ocean-bottom seismometers (recording two horizontal, one vertical and one pressure channel) were deployed during 2007-2008. During 13 months of deployment, abundant vocalizations of marine mammals have been recorded by all the five equipments. By analyzing the frequency content of data and their pattern of occurrence, we conclude that these low-frequency vocalizations (~20-40 Hz) typically corresponds to blue and fin-whales. These signals if not identified, could be mis-interpreted as underwater seismic/hydrothermal activity. Our data show an increase in the number of vocalizations recorded during the winter season relative to the summer. As part of the seismic monitoring of the Lucky-strike site, we anticipate to extend this study to the 2008-2009 and 2009-2010 periods, after the recovery and deployment of the array during the BATHYLUCK09 cruise. Long-term and continuous records of calls of marine mammals provide valuable information that could be used to identify the species, study their seasonal behaviour and their migration paths. Our study suggestes that passive experiments such as ocean-bottom seismometers deployed at key locations, could provide useful secondary infromation about oceanic species besides recording seismicity, which is otherwise not possible without harming or interfering with their activity.

  19. Occurrence and intake of deoxynivalenol in cereal-based products marketed in Korea during 2007-2008.

    PubMed

    Ok, H E; Chang, H-J; Choi, S-W; Cho, T Y; Oh, K S; Chun, H S

    2009-01-01

    The occurrence of deoxynivalenol (DON) was investigated in 514 cereal-based products (corn-based, n = 125; barley-based, n = 96; wheat-based, n = 94; rice-based, n = 199) marketed in Korea during 2007-2008, and estimates of DON intake were determined. Samples were analysed by high-performance liquid chromatography (HPLC) with ultraviolet light (UV) detection after immunoaffinity clean-up. The limits of detection (LOD) and limits of quantification (LOQ) were 2.2 and 5.6 µg kg(-1), respectively. Recoveries and repeatability expressed as coefficients of variation (CV) were 82.3-100% and 2.4-15.3% in beer, bread and dried corn. The incidences and mean levels of DON were 56% and 68.9 µg kg(-1) for corn-based products, 49% and 24.1 µg kg(-1) for wheat-based products, 43% and 7.5 µg kg(-1) for barley-based products, and 16% and 3.4 µg kg(-1) for rice-based products, respectively. The estimated daily intake of DON from the consumption of rice-based, wheat-based, barley-based and corn-based products were 0.0038 µg kg(-1) bw day(-1), 0.0032 µg kg(-1) bw day(-1), 0.0015 µg kg(-1) bw day(-1) and 0.0002 µg kg(-1) bw day(-1), respectively. These values represent 0.38%, 0.32%, 0.25% and 0.01% of the provisional maximum tolerable daily intake (PMTDI) of 1 µg kg(-1) bw day(-1). These results indicate that rice-based products are major contributors to DON exposure in Korea, even though the current exposure level is unlikely to cause adverse health effects. PMID:24785178

  20. Surveillance of antibiotic resistance in Neisseria gonorrhoeae in the WHO Western Pacific and South East Asian regions, 2007-2008.

    PubMed

    Tapsall, J W; Limnios, E A; Abu Bakar, Hjh Mahani Hj; Darussalam, Brunei; Ping, Yin Yue; Buadromo, E M; Kumar, P; Singh, S; Lo, J; Bala, M; Risbud, A; Deguchi, T; Tanaka, M; Watanabe, Y; Lee, K; Chong, Y; Noikaseumsy, S; Phouthavane, T; Sam, I-Ching; Tundev, O; Lwin, K M; Eh, P H; Goarant, C; Goursaud, R; Bathgate, T; Brokenshire, M; Latorre, L; Velemu, E; Carlos, C; Leano, S; Telan, E O; Goh, S S; Koh, S T; Ngan, C; Tan, A L; Mananwatte, S; Piyanoot, N; Lokpichat, S; Sirivongranson, P; Fakahau, M; Sitanilei, H; Hung, Le Van

    2010-03-01

    Long-term surveillance of antimicrobial resistance in Neisseria gonorrhoeae has been conducted in the World Health Organization (WHO) Western Pacific Region (WPR) to optimise antibiotic treatment of gonococcal disease since 1992. In 2007 and 2008, this Gonococcal Antimicrobial Surveillance Programme (GASP) was enhanced by the inclusion of data from the South East Asian Region (SEAR) and recruitment of additional centres within the WPR. Approximately 17,450 N. gonorrhoeae were examined for their susceptibility to one or more antibiotics used for the treatment of gonorrhoea by external quality controlled methods in 24 reporting centres in 20 countries and/or jurisdictions. A high proportion of penicillin and/or quinolone resistance was again detected amongst isolates tested in North Asia and the WHO SEAR, but much lower rates of penicillin resistance and little quinolone resistance was present in most of the Pacific Island countries. The proportion of gonococci reported as 'resistant', 'less susceptible' or 'non-susceptible' gonococci to the third-generation cephalosporin antibiotic ceftriaxone lay in a wide range, but no major changes were evident in cephalosporin minimal inhibitory concentration (MIC) patterns in 2007-2008. Altered cephalosporin susceptibility was associated with treatment failures following therapy with oral third-generation cephalosporins. There is a need for revision and clarification of some of the in vitro criteria that are currently used to categorise the clinical importance of gonococci with different ceftriaxone and oral cephalosporin MIC levels. The number of instances of spectinomycin resistance remained low. A high proportion of strains tested continued to exhibit a form of plasmid mediated high level resistance to tetracyclines. The continuing emergence and spread of antibiotic resistant gonococci in and from the WHO WPR and SEAR supports the need for gonococcal antimicrobial resistance surveillance programs such as GASP to be

  1. Monitoring the Migrations of Wild Snake River Spring/Summer Chinook Salmon Juveniles, 2007-2008 Report of Research.

    SciTech Connect

    Achord, Stephen; Sandford, Benjamin P.; Hockersmith, Eric E.

    2009-05-26

    This report provides results from an ongoing project to monitor the migration behavior and survival of wild juvenile spring/summer Chinook salmon in the Snake River Basin. Data reported is from detections of PIT tagged fish during late summer 2007 through mid-2008. Fish were tagged in summer 2007 by the National Marine Fisheries Service (NMFS) in Idaho and by the Oregon Department of Fish and Wildlife (ODFW) in Oregon. Our analyses include migration behavior and estimated survival of fish at instream PIT-tag monitors and arrival timing and estimated survival to Lower Granite Dam. Principal results from tagging and interrogation during 2007-2008 are listed below: (1) In July and August 2007, we PIT tagged and released 7,390 wild Chinook salmon parr in 12 Idaho streams or sample areas. (2) Overall observed mortality from collection, handling, tagging, and after a 24-hour holding period was 1.4%. (3) Of the 2,524 Chinook salmon parr PIT tagged and released in Valley Creek in summer 2007, 218 (8.6%) were detected at two instream PIT-tag monitoring systems in lower Valley Creek from late summer 2007 to the following spring 2008. Of these, 71.6% were detected in late summer/fall, 11.9% in winter, and 16.5% in spring. Estimated parr-to-smolt survival to Lower Granite Dam was 15.5% for the late summer/fall group, 48.0% for the winter group, and 58.5% for the spring group. Based on detections at downstream dams, the overall efficiency of VC1 (upper) or VC2 (lower) Valley Creek monitors for detecting these fish was 21.1%. Using this VC1 or VC2 efficiency, an estimated 40.8% of all summer-tagged parr survived to move out of Valley Creek, and their estimated survival from that point to Lower Granite Dam was 26.5%. Overall estimated parr-to-smolt survival for all summer-tagged parr from this stream at the dam was 12.1%. Development and improvement of instream PIT-tag monitoring systems continued throughout 2007 and 2008. (4) Testing of PIT-tag antennas in lower Big Creek during

  2. The International Polar Year in Portugal: A New National Polar Programme and a Major Education and Outreach project

    NASA Astrophysics Data System (ADS)

    Mendes-Victor, L.; Vieira, G.; Xavier, J.; Canario, A.

    2008-12-01

    Before the International Polar Year, in Portugal polar research was conducted by a very small group of scientists integrated in foreign projects or research institutions. Portugal was not member of the Scientific Committee for Antarctic Research (SCAR), the European Polar Board (EPB), neither a subscriber of the Antarctic Treaty. In 2004 Portuguese Polar researchers considered the IPY as an opportunity to change this situation and organized the national Committee for the IPY. The objectives were ambitious: to answer the aforementioned issues in defining and proposing a National Polar Programme. In late 2008, close to the end of the IPY, the objectives were attained, except the Antarctic Treaty signature that is, however, in an advanced stage, having been approved by consensus at the National Parliament in early 2007. Portugal joined SCAR in July 2006, the EPB in 2007 and a set of 5 Antarctic research projects forming the roots of the National Polar Programme (ProPolar) have been approved by the Foundation for Science and Technology (FCT-MCTES). Scientifically, the IPY can already be considered a major success in Portugal with an improvement in polar scientific research, in the number of scientists performing field work in the Antarctic, organizing polar science meetings and producing an expected increase in the number of polar science peer- reviewed papers. The Portuguese IPY scientific activities were accompanied by a major education and outreach project funded by the Agencia Ciência Viva (MCTES): LATITUDE60! Education for the Planet in the IPY. This project lead by the universities of Algarve, Lisbon and by the Portuguese Association of Geography Teachers is heavily interdisciplinary, programmed for all ages, from kindergarten to adults, and hoped to bring together scientists and society. LATITUDE60! was a major success and focussed on showing the importance of the polar regions for Earth's environment, emphasising on the implications of polar change for

  3. Internal structure of the Martian south polar layered deposits

    NASA Astrophysics Data System (ADS)

    Byrne, S.; Ivanov, A. B.

    2004-11-01

    We investigate the three-dimensional (3-D) stratigraphic structure of the south polar layered deposits (SPLD) on Mars. Prominent bench-forming layers exposed on SPLD scarps were observed and mapped in three dimensions using high-resolution topographic and imaging data sets. Using the 3-D location of exposures of one of these strata, we can accurately describe the shape of that layer using simple mathematical functions. Analysis of these functions and the surface topography can be used to reliably predict where on other scarps this layer is exposed. In general this bench-forming layer (and its surrounding strata) is not flat and is well approximated as a parabolic dome near the center of the SPLD. Its curvature indicates that when deposited it was draped over a topographic dome similar in size to that of the present day. The scarps in which this layer is exposed must have formed subsequently and have not been significantly modified by flow processes. The basement topography exercises some control over the shape of the interior strata in extreme cases. Our successful layer-fitting technique illustrates the regional uniformity in layer formation and the lack of major internal defects (such as faulting) within the SPLD. We have mapped exposures of what appear to be this layer in scarps farther from the center of the deposits. The position of these exposures can be used to modify the modeled parabolic shape at the periphery of the SPLD. These peripheral elevations provide constraints on the role of flow in the overall shaping of the SPLD.

  4. The Polarized Electron Source for the International Collider (ILC) Project

    NASA Astrophysics Data System (ADS)

    Brachmann, A.; Clendenin, J. E.; Garwin, E. L.; Ioakeimidi, K.; Kirby, R. E.; Maruyama, T.; Prescott, C. Y.; Sheppard, J.; Turner, J.; Zhou, F.

    2007-06-01

    The ILC project will be the next large high energy physics tool that will use polarized electrons (and positrons). For this machine spin physics will play an important role. The polarized electron source design is based on electron injectors built for the Stanford Linear Collider (polarized) and Tesla Test Facility (un-polarized). The ILC polarized electron source will provide a 5GeV spin polarized electron beam for injection into the ILC damping ring. Although most ILC machine parameters have been achieved by the SLC or TTF source, features of both must be integrated into one design. The bunch train structure presents unique challenges to the source laser drive system. A suitable laser system has not yet been demonstrated and is part of the ongoing R&D program for ILC at SLAC. Furthermore, ILC injector R&D incorporates photocathode development, increasing available polarization, and improving operational properties in gun vacuum systems. Another important area of research and development is advancing the design of DC and RF electron gun technology for polarized sources. This presentation presents the current status of the design and outlines aspects of the relevant R&D program carried out within the ILC community.

  5. Magma mixing and forced exsolution of CO2 during the explosive 2007-2008 eruption of Oldoinyo Lengai (Tanzania)

    NASA Astrophysics Data System (ADS)

    Bosshard-Stadlin, Sonja A.; Mattsson, Hannes B.; Keller, Jörg

    2014-09-01

    Oldoinyo Lengai is probably most famous for being the only active volcano on Earth which is erupting natrocarbonatitic magma. However, the mildly explosive natrocarbonatitic activity is alternating with highly explosive, nephelinitic eruptions of which the most recent episode occurred in September 2007 (and lasted until April 2008). Here we present petrographic observations, mineral chemistry as well as major- and trace element analyses of samples covering the evolution of the eruption with time. In the early phases of the eruption, the phenocryst assemblages are dominated by the carbonate minerals nyerereite and gregoryite, but as the eruption progresses the mineralogy becomes dominated by silicate minerals like nepheline, pyroxene, garnet, alumoåkermanite, combeite and wollastonite. The observed major- and trace element variations during the 2007-2008 eruption indicate mixing between a natrocarbonatitic magma and a combeite-wollastonite-bearing nephelinitic magma (CWN), with higher portions of natrocarbonatite in the early stages of the eruption. Euhedral and uncorroded clinopyroxene crystals are abundant in the late 2007 deposits but quickly start to break-down and corrode as the eruption continues, indicating that the natrocarbonatite and the CWN are not in fact conjugate magmas derived from a single magma reservoir, but must have evolved separately in the crust from the point of immiscibility. When these magmas interact beneath the volcano, a hybrid silicate magma forms (where clinopyroxene is no longer stable) and the composition of this hybrid causes the overall solubility of CO2 in the system to decrease drastically. This results in rapid exsolution of CO2 (g) which is allowed to expand during ascent, and we conclude that this is most likely the reason behind the unexpected vigor in the explosive eruptions of Oldoinyo Lengai. This massive release of CO2 during ascent may also explain the petrographic features of the pyroclasts as these are dominated by

  6. An International Polar Year Adventure in the Arctic

    NASA Astrophysics Data System (ADS)

    Wartes, D.

    2008-12-01

    Native students in the UA system who participated in RAHI are nearly twice as likely to earn a bachelor's degree, than those who did not attend RAHI. The past two summers, in celebration of the International Polar Year, in collaboration with Ilisagvik College, at the completion of the traditional RAHI program, ten RAHI students flew to Barrow for an additional two weeks of study. Five students participated in an archaeological dig and five students performed research with the Barrow Arctic Science Consortium scientists studying climate change. And another student was the Alaskan delegate to the Students on Ice, a 2-week ship-based adventure in northern Canada. In addition, ten students from Greenland visited the program, with plans to more fully participate next summer. This added dimension to the program has proved successful, allowing the students to compare and contrast between their own countries and indigenous perspectives. Global warming was an issue that was hotly debated, as its effects are so evident in the Polar Regions. In the Arctic, one's life is directly tied to the ice and snow. As the ice disappears and/or changes, the Indigenous people have to adapt. RAHI would like to share with you some of the results of this past summer's IPY activities.

  7. International solar polar mission: The vector helium magnetometer

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The functional requirements for the vector helium magnetometer (VHM) on the Solar Polar spacecraft are presented. The VHM is one of the two magnetometers on board that will measure the vector magnetic field along the Earth to Jupiter transfer trajectory, as well as in the vicinity of Jupiter and along the solar polar orbit following the Jupiter encounter. The interconnection between these two magnetometers and their shared data processing unit is illustrated.

  8. A polarized internal sup 3 He target using optical pumping of metastable atoms

    SciTech Connect

    McKeown, R.D.; Milner, R.G.; Woodward, C.E. )

    1989-05-05

    The design of a polarized internal {sup 3}He target for use in storage rings based on optical pumping of metastables is discussed. The target employs an infrared laser to polarize {sup 3}He atoms in a pyrex cell which is connected by a capillary to a windowless cell through which the stored beam passes. Using this technique it should be possible construct targets of 50% polarized {sup 3}He targets of thickness 10{sup 16} cm{sup {minus}2}. Small holding fields ({similar to}10 gauss) and resistance to beam-induced depolarization are desirable features of this target in a storage ring environment.

  9. Integrated optic polarization splitter based on total internal reflection from a birefringent polymer.

    PubMed

    Huang, Guanghao; Park, Tae-Hyun; Chu, Woo-Sung; Oh, Min-Cheol

    2016-09-01

    An integrated optic polarization splitter with large fabrication tolerance and high reliability is required for optical signal processing in quantum-encrypted communication systems. A polarization splitter based on total internal reflection from a highly birefringent polymer-reactive mesogen-is proposed and demonstrated in this work. The device consists of a mode expander for reducing the wave vector distribution of the guided mode, and an interface with a large birefringence. Several polymers with suitable refractive indexes were used for fabricating the device. We obtained a polarization splitter with a low crosstalk (less than -30 dB), and a large fabrication tolerance. PMID:27607704

  10. A synopsis of oncology and oncology-related papers published in the British Journal of Oral and Maxillofacial Surgery 2007-2008.

    PubMed

    Brennan, P A; Shekar, K; McLeod, N; Puxeddu, R; Cascarini, L

    2009-10-01

    This paper provides a summary of the 95 papers related to oncology that were published in the British Journal of Oral and Maxillofacial Surgery (BJOMS) during 2007-2008. They include full length articles on clinical studies, radiology, basic science, and reconstruction in oral, and head and neck cancer. The journal also publishes technical notes and short communications. It encompasses the whole remit of the specialty and it is encouraging that authors choose to submit their work to BJOMS, but to improve the quality and status of the journal, we need to increase the ratio of full length articles to other submissions. Reviews of other subspecialties will be published in due course. PMID:19665266

  11. Using International Polar Days to Engage and Experiment with Science - Outreach Partnerships in IPY

    NASA Astrophysics Data System (ADS)

    Salmon, R. A.; Munro, N.; Carlson, D.; Pauls, M.; Zicus, S.

    2008-12-01

    The International IPY Education, Outreach, and Communication Committee developed quarterly International Polar Days in response to pressure from educators and media wishing to remain involved in IPY, throughout IPY. Between September 2007 and March 2009 these events focus on aspects of polar research that are both specific enough to allow depth of understanding, but also broad enough to highlight the interconnectivity of polar science. Each day has experimented with different communication tools including multilingual activity and summary sheets, live radio and web events, press releases, local lectures and engagement at conferences. A virtual balloon launch helps us to assess our reach and develop plans for the next event. The talk will present an evaluation from the balloon launch as well as lessons learnt from activities that had varying degrees of success.

  12. Arctic Research and Writing: A Lasting Legacy of the International Polar Year

    ERIC Educational Resources Information Center

    Englert, Karl; Coon, Brian; Hinckley, Matt; Pruis, Matt

    2009-01-01

    Recently, senior-level physics students joined thousands of scientists from over 60 nations to examine a wide range of physical, biological, and social research topics as part of the International Polar Year (IPY). Through a National Science Foundation (NSF)-funded research project, these students applied physics concepts to the study of Arctic…

  13. Celebrate with SATELLITES: An International Polar Year Partnership to Study Earth's Materials

    ERIC Educational Resources Information Center

    Hedley, Mikell Lynne; Czajkowski, Kevin; Struble, Janet; Benko, Terri; Shellito, Brad; Sheridan, Scott; Stasiuk, Mandy Munroe

    2009-01-01

    The SATELLITES program uses geospatial technologies to study surface temperatures of Earth's materials, such as sand, soil, grass, and water. Data are collected using Global Learning and Observations to Benefit the Environment (GLOBE) protocols, which are then used in research projects that are a part of the International Polar Year (IPY).…

  14. A Rising Tide for Polar Science: Efforts of the U.S. National Committee for the International Polar Year

    NASA Astrophysics Data System (ADS)

    Albert, M. R.

    2003-12-01

    The polar regions, fascinating yet distant and cold places, hold the keys to our changing world. While the upcoming IPY is the 50th anniversary of the International Geophysical Year and the 125th anniversary of the first International Polar Year, it also falls at a crucial time in rapid changes in environmental and social systems that may affect all peoples of the Earth. Further warming of the Arctic, changing ecosystems and opening pathways for ocean travel, impact not only the people there but also the shipping, economics, and strategic considerations of distant nations. Yet potential further warming of the Arctic may be understood by clues in the Antarctic ice. How are the polar regions changing, and how swiftly may those changes affect the entire Earth? This is but one question emerging from community discussions of the science of the upcoming IPY. Our emerging ability to investigate previously unexplored areas is increasing our understanding of the wide world we live in, through interdisciplinary studies and tools for connections. Autonomous vehicles, genomics, and remote sensing technologies are just a few of the emerging areas that may provide new tools for investigating previously inaccessible realms. At the same time, tools such as the internet are making the world smaller, enabling instant communications between the peoples of the world. Joint international investigations enhance our ability to understand one another as well as our ability to understand our world and our universe. Rapid communications and international involvement can revolutionize the way we educate young scientists and our future leaders in a complex and changing world. Involving and educating people - young scientists, college students, school children, and the public - will be included as hallmarks of the IPY. The people are here. New tools are emerging. The ideas, or scientific goals, of the IPY are being crafted jointly through broad involvement of the scientific community, through

  15. From Auroras to Sea Ice: Views From the International Space Station and Plans for International Polar Year

    NASA Technical Reports Server (NTRS)

    Evans, Cynthia A.; Runco, Susan K.; Heydorn, James; Trenchard, Michael; Stefanov, William L.; Wilkinson, M. Justin

    2006-01-01

    For more than 40 years astronauts have been observing Earth, taking photographs or digital images from their spacecraft. Today, a robust program of observation from the International Space Station (ISS) has yielded hundreds of thousands of images of the Earth s surface collected since 2001. Seeing Earth through the eyes of an astronaut is exciting to the general public, and the images are popular in classrooms. Because the ISS has an orbital inclination of 51.6 degrees (the north-south limits of the orbit are at 51.6 degrees latitude), high latitude observations are common. Some of the most striking images collected include views of polar phenomena. Astronauts routinely pass above brilliant red and green aurora; view high, wispy clouds at the top of the atmosphere; or look down on glaciers and floating ice rafts. These images, framed and captured by humans, are easily interpreted by students and teachers. Astronaut observations provide a way to visualize complicated polar phenomena and communicate about them to students of all ages. Over the next two years, astronauts aboard the ISS will formally focus their observations on polar phenomena as participants in the International Polar Year (IPY). Imagery acquisition from the ISS will be coordinated with other IPY scientists staging studies and field campaigns on the ground. The imagery collected from the ISS will be cataloged and served on NASA s web-based database of images, http://eol.jsc.nasa.gov . The website allows investigators, students and teachers to search through the imagery, assemble image datasets, and download the imagery and the metadata. We display some of the most spectacular examples of polar imagery and demonstrate NASA s database of astronaut images of Earth.

  16. From Auroras to Sea Ice: Views From the International Space Station and Plans for International Polar Year

    NASA Astrophysics Data System (ADS)

    Evans, C. A.; Runco, S. K.; Willis, K.; Heydorn, J.; Trenchard, M.; Stefanov, W. L.; Wilkinson, M. J.

    2006-12-01

    For more than 40 years astronauts have been observing Earth, taking photographs or digital images from their spacecraft. Today, a robust program of observation from the International Space Station (ISS) has yielded hundreds of thousands of images of the Earth's surface collected since 2001. Seeing Earth through the eyes of an astronaut is exciting to the general public, and the images are popular in classrooms. Because the ISS has an orbital inclination of 51.6 degrees (the north-south limits of the orbit are at 51.6 degrees latitude), high latitude observations are common. Some of the most striking images collected include views of polar phenomena. Astronauts routinely pass above brilliant red and green aurora; view high, wispy clouds at the top of the atmosphere; or look down on glaciers and floating ice rafts. These images, framed and captured by humans, are easily interpreted by students and teachers. Astronaut observations provide a way to visualize complicated polar phenomena and communicate about them to students of all ages. Over the next two years, astronauts aboard the ISS will formally focus their observations on polar phenomena as participants in the International Polar Year (IPY). Imagery acquisition from the ISS will be coordinated with other IPY scientists staging studies and field campaigns on the ground. The imagery collected from the ISS will be cataloged and served on NASA's web-based database of images, http://eol.jsc.nasa.gov . The website allows investigators, students and teachers to search through the imagery, assemble image datasets, and download the imagery and the metadata. We display some of the most spectacular examples of polar imagery and demonstrate NASA's database of astronaut images of Earth.

  17. Knowledge Discovery in our World Information Society: Opportunities for the International Polar Year 2007-08

    NASA Astrophysics Data System (ADS)

    Berkman, P. A.

    2005-12-01

    The World Data Center system emerged in 1957-58 with the International Geophysical Year (which was renamed from the 3rd International Polar Year) to preserve and provide access to scientific data collected from observational programs throughout the Earth system. Fast forward a half century ... access to diverse digital information has become effectively infinite and instantaneous with nearly 20,000 petabytes of information produced and stored on print, optical and magnetic media each year; microprocessor speeds that have increased 5 orders of magnitude since 1972; existence of the Internet; increasing global capacity to collect and transmit information via satellites; availability of powerful search engines; and proliferation of data warehouses like the World Data Centers. The problem is that we already have reached the threshold in our world information society when accessing more information does not equate with generating more knowledge. In 2007-08, the International Council of Science and World Meteorological Organization will convene the next International Polar Year to accelerate our understanding of how the polar regions respond to, amplify and drive changes elsewhere in the Earth system (http://www.ipy.org). Beyond Earth system science, strategies and tools for integrating digital information to discover meaningful relationships among the disparate data would have societal benefits from boardrooms to classrooms. In the same sense that human-launched satellites became a strategic focus that justified national investments in the International Geophysical Year, developing the next generation of knowledge discovery tools is an opportunity for the International Polar Year 2007-08 and its affiliated programs to contribute in an area that is critical to the future of our global community. Knowledge is the common wealth of humanity. H.E. Mr. Adama Samassekou President, World Summit on the Information Society

  18. Frontier Science in the Polar Regions: Current Activities of the Polar Research Board

    NASA Astrophysics Data System (ADS)

    Brown, L. M.

    2011-12-01

    Southern Ocean will be summarized. The report will identify the anticipated types and scope of US scientific programs in the region over the next two decades. It will also examine opportunities for international Antarctic scientific collaborations and report any new and emerging technologies. Through these reports, ongoing studies and workshops, and various outreach methods, the PRB plays an important role in dissemination of polar science, both in the United States and internationally. For example, the PRB played a critical role in planning the International Polar Year (IPY) 2007-2008 and is currently conducting a synthesis study called Legacies and Lessons of IPY 2007-2008. The report will be informed by a large community workshop and will examine what was learned and how the many pieces of IPY combine to move polar understanding forward in the future. Other PRB reports (e.g., Scientific Value of Arctic Sea Ice Imagery Derived Products and Toward an Integrated Arctic Observing Network) have also had important implications for current and future polar research.

  19. International conference on the role of the polar regions in global change: Proceedings. Volume 2

    SciTech Connect

    Weller, G.; Wilson, C.L.; Severin, B.A.B.

    1991-12-01

    The International Conference on the Role of the Polar Regions in Global Change took place on the campus of the University of Alaska Fairbanks on June 11--15, 1990. The goal of the conference was to define and summarize the state of knowledge on the role of the polar regions in global change, and to identify gaps in knowledge. To this purpose experts in a wide variety of relevant disciplines were invited to present papers and hold panel discussions. While there are numerous conferences on global change, this conference dealt specifically with the polar regions which occupy key positions in the global system. These two volumes of conference proceedings include papers on (1) detection and monitoring of change; (2) climate variability and climate forcing; (3) ocean, sea ice, and atmosphere interactions and processes; and (4) effects on biota and biological feedbacks; (5) ice sheet, glacier and permafrost responses and feedbacks, (6) paleoenvironmental studies; and, (7) aerosol and trace gases.

  20. International conference on the role of the polar regions in global change: Proceedings. Volume 1

    SciTech Connect

    Weller, G.; Wilson, C.L.; Severin, B.A.B.

    1991-12-01

    The International Conference on the Role of the Polar Regions in Global Change took place on the campus of the University of Alaska Fairbanks on June 11--15, 1990. The goal of the conference was to define and summarize the state of knowledge on the role of the polar regions in global change, and to identify gaps in knowledge. To this purpose experts in a wide variety of relevant disciplines were invited to present papers and hold panel discussions. While there are numerous conferences on global change, this conference dealt specifically with polar regions which occupy key positions in the global system. These two volumes of conference proceedings include papers on (1) detection and monitoring of change; (2) climate variability and climate forcing; (3) ocean, sea ice, and atmosphere interactions and processes; (4) effects on biota and biological feedbacks; (5) ice sheet, glacier and permafrost responses and feedbacks; (6) paleoenvironmental studies; and, (7) aerosols and trace gases.

  1. The University of Delaware Carlson International Polar Year Events: Collaborative and Educational Outreach

    NASA Astrophysics Data System (ADS)

    Nelson, F. E.; Bryant, T.; Wellington, P.; Dooley, J.; Bird, M.

    2008-12-01

    Delaware is a small state with, by virtue of its coastal location, a large stake in climatic change in the polar regions. The University of Delaware has maintained a strong presence in cold-regions research since the mid-1940s, when William Samuel Carlson, a highly accomplished Arctic explorer, military strategist, and earth scientist, was named 20th President (1946-50) of the University. Carlson played a leading role in two of the University of Michigan's Greenland expeditions in the late 1920s and early 1930s. As Director of the Arctic, Desert, and Tropic Branch of the US Army Air Forces Tactical Center during World War II, Colonel Carlson played a role in developing several air transportation routes through the Arctic that helped to facilitate the Allied victory in Europe. Carlson authored many scientific and popular publications concerned with the Arctic, including the books Greenland Lies North (1940) and Lifelines Through the Arctic (1962). Although the University of Delaware has maintained a vigorous and continuous program of polar research since Carlson's tenure, the faculty, staff, and students involved are diffused throughout the University's colleges and departments, without an institutional focal point. Consequently, although many of these individuals are well known in their respective fields, the institution has not until recently been perceived widely as a center of polar-oriented research. The goals of the Carlson International Polar Year Events are to: (a) develop a sense of community among UD's diffuse polar-oriented researchers and educators; (b) create a distinctive and highly visible role for UD in the milieu of IPY activities; (c) promote interest in and knowledge about the polar regions in the State of Delaware, at all educational levels; (d) forge a close relationship between UD and the American Geographical Society, a national organization involved closely with previous International Polar Years; and (e) create a new basis for development

  2. Exploring two-spin internal linear combinations for the recovery of the CMB polarization

    NASA Astrophysics Data System (ADS)

    Fernández-Cobos, R.; Marcos-Caballero, A.; Vielva, P.; Martínez-González, E.; Barreiro, R. B.

    2016-06-01

    We present a methodology to recover cosmic microwave background (CMB) polarization in which the quantity P = Q + iU is linearly combined at different frequencies using complex coefficients. This is the most general linear combination of the Q and U Stokes parameters which preserves the physical coherence of the residual contribution on the CMB estimation. The approach is applied to the internal linear combination (ILC) and the internal template fitting (ITF) methodologies. The variance of P of the resulting map is minimized to compute the coefficients of the linear combination. One of the key aspects of this procedure is that it serves to account for a global frequency-dependent shift of the polarization phase. Although in the standard case, in which no global E-B transference depending on frequency is expected in the foreground components, minimizing <|P|2> is similar to minimizing and separately (as previous methodologies proceed), multiplying Q and U by different coefficients induces arbitrary changes in the polarization angle and it does not preserve the coherence between the spinorial components. The approach is tested on simulations, obtaining a similar residual level with respect to the one obtained with other implementations of the ILC, and perceiving the polarization rotation of a toy model with the frequency dependence of the Faraday rotation.

  3. Assessment of chemical coexposure patterns based upon phthalate biomonitoring data within the 2007/2008 National Health and Nutrition Examination Survey

    PubMed Central

    Qian, Hua; Chen, Min; Kransler, Kevin M; Zaleski, Rosemary T

    2015-01-01

    As regulatory initiatives increasingly call for an understanding of the cumulative risks from chemical mixtures, evaluating exposure data from large biomonitoring programs, which may inform these cumulative risk assessments, will improve the understanding of occurrence and patterns of coexposures. Here we have analyzed the urinary metabolite data for six phthalates (di-butyl phthalate; di-isobutyl phthalate; butyl-benzyl phthalate; bis(2-ethylhexyl) phthalate; di-isononyl phthalate; and di-isodecyl phthalate) in the 2007/2008 National Health and Nutrition Examination Survey (NHANES) data set. For the total data set (N=2604), the co-occurrence of multiple phthalates at the upper percentile of exposure was infrequent. There were no individuals in the NHANES sample who were exposed to >95th percentiles for all six phthalates. For 75% of individuals, none of the six phthalates were above the 95th percentile of their respective exposure distributions. These data suggest that high exposure to multiple phthalates is infrequent in the NHANES population. This analysis solely focused on the pattern of contribution of individual phthalates to total exposure. It did not address the pattern of contribution to potential risk. The approach presented could potentially be used to provide insight into understanding the coexposure patterns for other chemicals. PMID:24756100

  4. Changing patterns of spatial clustering of schistosomiasis in Southwest China between 1999-2001 and 2007-2008: assessing progress toward eradication after the World Bank Loan Project.

    PubMed

    Hu, Yi; Xiong, Chenglong; Zhang, Zhijie; Luo, Can; Cohen, Ted; Gao, Jie; Zhang, Lijuan; Jiang, Qingwu

    2014-01-01

    We compared changes in the spatial clustering of schistosomiasis in Southwest China at the conclusion of and six years following the end of the World Bank Loan Project (WBLP), the control strategy of which was focused on the large-scale use of chemotherapy. Parasitological data were obtained through standardized surveys conducted in 1999-2001 and again in 2007-2008. Two alternate spatial cluster methods were used to identify spatial clusters of cases: Anselin's Local Moran's I test and Kulldorff's spatial scan statistic. Substantial reductions in the burden of schistosomiasis were found after the end of the WBLP, but the spatial extent of schistosomiasis was not reduced across the study area. Spatial clusters continued to occur in three regions: Chengdu Plain, Yangtze River Valley, and Lancang River Valley during the two periods, and regularly involved five counties. These findings suggest that despite impressive reductions in burden, the hilly and mountainous regions of Southwest China remain at risk of schistosome re-emergence. Our results help to highlight specific locations where integrated control programs can focus to speed the elimination of schistosomiasis in China. PMID:24394217

  5. Assessment of chemical coexposure patterns based upon phthalate biomonitoring data within the 2007/2008 National Health and Nutrition Examination Survey.

    PubMed

    Qian, Hua; Chen, Min; Kransler, Kevin M; Zaleski, Rosemary T

    2015-05-01

    As regulatory initiatives increasingly call for an understanding of the cumulative risks from chemical mixtures, evaluating exposure data from large biomonitoring programs, which may inform these cumulative risk assessments, will improve the understanding of occurrence and patterns of coexposures. Here we have analyzed the urinary metabolite data for six phthalates (di-butyl phthalate; di-isobutyl phthalate; butyl-benzyl phthalate; bis(2-ethylhexyl) phthalate; di-isononyl phthalate; and di-isodecyl phthalate) in the 2007/2008 National Health and Nutrition Examination Survey (NHANES) data set. For the total data set (N=2604), the co-occurrence of multiple phthalates at the upper percentile of exposure was infrequent. There were no individuals in the NHANES sample who were exposed to >95th percentiles for all six phthalates. For 75% of individuals, none of the six phthalates were above the 95th percentile of their respective exposure distributions. These data suggest that high exposure to multiple phthalates is infrequent in the NHANES population. This analysis solely focused on the pattern of contribution of individual phthalates to total exposure. It did not address the pattern of contribution to potential risk. The approach presented could potentially be used to provide insight into understanding the coexposure patterns for other chemicals. PMID:24756100

  6. Using electronic polarization from the internal continuum (EPIC) for intermolecular interactions.

    PubMed

    Truchon, Jean-François; Nicholl's, Anthony; Grant, J Andrew; Iftimie, Radu I; Roux, Benoît; Bayly, Christopher I

    2010-03-01

    Recently, the vacuum-phase molecular polarizability tensor of various molecules has been accurately modeled (Truchon et al., J Chem Theory Comput 2008, 4, 1480) with an intramolecular continuum dielectric model. This preliminary study showed that electronic polarization can be accurately modeled when combined with appropriate dielectric constants and atomic radii. In this article, using the parameters developed to reproduce ab initio quantum mechanical (QM) molecular polarizability tensors, we extend the application of the "electronic polarization from internal continuu" (EPIC) approach to intermolecular interactions. We first derive a dielectric-adapted least-square-fit procedure similar to RESP, called DRESP, to generate atomic partial charges based on a fit to a QM abinitio electrostatic potential (ESP). We also outline a procedure to adapt any existing charge model to EPIC. The ability of this to reproduce local polarization, as opposed to uniform polarization, is also examined leading to an induced ESP relative root mean square deviation of 1%, relative to ab initio, when averaged over 37 molecules including aromatics and alkanes. The advantage of using a continuum model as opposed to an atom-centered polarizable potential is illustrated with a symmetrically perturbed atom and benzene. We apply EPIC to a cation-pi binding system formed by an atomic cation and benzene and show that the EPIC approach can accurately account for the induction energy. Finally, this article shows that the ab initio electrostatic component in the difficult case of the H-bonded 4-pyridone dimer, a highly polar and polarized interaction, is well reproduced without adjusting the vacuum-phase parameters. PMID:19598266

  7. Observation of internal wave polarity conversion generated by a rising tide

    NASA Astrophysics Data System (ADS)

    Li, Lan; Wang, Caixia; Grimshaw, Roger

    2015-05-01

    The observations reported here are based on time series of in situ observation data in Laoshan Bay off the Qingdao coast. A chain of thermistors (T-chain) at a fixed location recorded a sequence of elevation internal waves followed by depression internal waves passing by over an elapsed time of about 1 h. This observed polarity conversion at a fixed location is caused by the vertical stratification variation mainly induced by the rising tide, which is believed to be the first reported observation of this kind. The process of an elevation internal wave train converting to a depression wave train is simulated using the variable-coefficient extended Korteweg-de Vries (veKdV) equation, which also provides a further comparison between theory and the reported observations.

  8. Changes in mean intake of fatty acids and intake of saturated and trans fats from potatoes: NHANES 2005-2006, 2007-2008, and 2009-2010.

    PubMed

    Storey, Maureen L; Anderson, Patricia A

    2015-05-01

    Studies have shown that higher than usual intakes of trans fatty acids (TFAs) have adverse effects on blood lipids. Because of this, in 2006 the US FDA mandated labeling of TFAs on food packages. The food and restaurant industries, including the potato industry, reformulated their foods to reduce or eliminate partially hydrogenated vegetable oils and TFAs. Before mandatory labeling, grain-based desserts, yeast breads, and French-fried potatoes (FFPs) were the top sources of TFAs in the food supply; by 2007, potato food manufacturers and quick-service restaurants had reduced or eliminated TFAs without increasing saturated fatty acids (SFAs). FFPs are no longer a source of TFAs in the food supply. This study examined energy and fatty acid intake among children aged 6-11 y, adolescents aged 12-18 y, and adults aged ≥19 y across 3 time periods by using data from the NHANES 2005-2006, 2007-2008, and 2009-2010. On average, intakes of total energy, total fat, SFAs, and monounsaturated fatty acids (MUFAs) decreased significantly between 2005-2006 and 2009-2010 among children and adolescents; however, the intake of polyunsaturated fatty acids (PUFAs) did not change. Among adults, intakes of total fat, SFAs, and MUFAs decreased; however, total energy and PUFA intake did not change. On the day of the 2009-2010 survey, ∼13% of children and 10% of adolescents reported consuming fried FFPs, whereas <7% of adults reported consumption of fried FFPs. Intakes of SFAs and TFAs from fried FFPs decreased significantly between 2005-2006 and 2009-2010 among children, adolescents, and adults. This study confirms that intake of TFAs from FFPs is trivial. PMID:25979511

  9. Trends in antifungal drug susceptibility of Cryptococcus neoformans isolates obtained through population-based surveillance in South Africa in 2002-2003 and 2007-2008.

    PubMed

    Govender, Nelesh P; Patel, Jaymati; van Wyk, Marelize; Chiller, Tom M; Lockhart, Shawn R

    2011-06-01

    Cryptococcus neoformans is the most common cause of meningitis among adult South Africans with HIV infection/AIDS. Widespread use of fluconazole for treatment of cryptococcal meningitis and other HIV-associated opportunistic fungal infections in South Africa may lead to the emergence of isolates with reduced fluconazole susceptibility. MIC testing using a reference broth microdilution method was used to determine if isolates with reduced susceptibility to fluconazole or amphotericin B had emerged among cases of incident disease. Incident isolates were tested from two surveillance periods (2002-2003 and 2007-2008) when population-based surveillance was conducted in Gauteng Province, South Africa. These isolates were also tested for susceptibility to flucytosine, itraconazole, voriconazole, and posaconazole. Serially collected isolate pairs from cases at several large South African hospitals were also tested for susceptibility to fluconazole. Of the 487 incident isolates tested, only 3 (0.6%) demonstrated a fluconazole MIC of ≥ 16 μg/ml; all of these isolates were from 2002-2003. All incident isolates were inhibited by very low concentrations of amphotericin B and exhibited very low MICs to voriconazole and posaconazole. Of 67 cases with serially collected isolate pairs, only 1 case was detected where the isolate collected more than 30 days later had a fluconazole MIC value significantly higher than the MIC of the corresponding incident isolate. Although routine antifungal susceptibility testing of incident isolates is not currently recommended in clinical settings, it is still clearly important for public health to periodically monitor for the emergence of resistance. PMID:21444707

  10. Fundamental changes in the activity of the natrocarbonatite volcano Oldoinyo Lengai, Tanzania. II. Eruptive behaviour during the 2007-2008 explosive eruptions

    NASA Astrophysics Data System (ADS)

    Kervyn, Matthieu; Ernst, Gerald G. J.; Keller, Jörg; Vaughan, R. Greg; Klaudius, Jurgis; Pradal, Evelyne; Belton, Frederic; Mattsson, Hannes B.; Mbede, Evelyne; Jacobs, Patric

    2010-10-01

    On September 4, 2007, after 25 years of effusive natrocarbonatite eruptions, the eruptive activity of Oldoinyo Lengai (OL), N Tanzania, changed abruptly to episodic explosive eruptions. This transition was preceded by a voluminous lava eruption in March 2006, a year of quiescence, resumption of natrocarbonatite eruptions in June 2007, and a volcano-tectonic earthquake swarm in July 2007. Despite the lack of ground-based monitoring, the evolution in OL eruption dynamics is documented based on the available field observations, ASTER and MODIS satellite images, and almost-daily photos provided by local pilots. Satellite data enabled identification of a phase of voluminous lava effusion in the 2 weeks prior to the onset of explosive eruptions. After the onset, the activity varied from 100 m high ash jets to 2-15 km high violent, steady or unsteady, eruption columns dispersing ash to 100 km distance. The explosive eruptions built up a ˜400 m wide, ˜75 m high intra-crater pyroclastic cone. Time series data for eruption column height show distinct peaks at the end of September 2007 and February 2008, the latter being associated with the first pyroclastic flows to be documented at OL. Chemical analyses of the erupted products, presented in a companion paper (Keller et al. 2010), show that the 2007-2008 explosive eruptions are associated with an undersaturated carbonated silicate melt. This new phase of explosive eruptions provides constraints on the factors causing the transition from natrocarbonatite effusive eruptions to explosive eruptions of carbonated nephelinite magma, observed repetitively in the last 100 years at OL.

  11. Fundamental changes in the activity of the natrocarbonatite volcano Oldoinyo Lengai, Tanzania. I. New magma composition during the 2007-2008 explosive eruptions

    NASA Astrophysics Data System (ADS)

    Keller, Jörg; Klaudius, Jurgis; Kervyn, Matthieu; Ernst, Gerald G. J.; Mattsson, Hannes B.

    2010-10-01

    With a paroxysmal ash eruption on 4 September 2007 and the highly explosive activity continuing in 2008, Oldoinyo Lengai (OL) has dramatically changed its behavior, crater morphology, and magma composition after 25 years of quiet extrusion of fluid natrocarbonatite lava. This explosive activity resembles the explosive phases of 1917, 1940-1941, and 1966-1967, which were characterized by mixed ashes with dominantly nephelinitic and natrocarbonatitic components. Ash and lapilli from the 2007-2008 explosive phase were collected on the slopes of OL as well as on the active cinder cone, which now occupies the entire north crater having buried completely all earlier natrocarbonatite features. The lapilli and ash samples comprise nepheline, wollastonite, combeite, Na-åkermanite, Ti-andradite, resorbed pyroxene and Fe-Ti oxides, and a Na-Ca carbonate phase with high but varying phosphorus contents which is similar, but not identical, to the common gregoryite phenocrysts in natrocarbonatite. Lapilli from the active cone best characterize the erupted material as carbonated combeite-wollastonite-melilite nephelinite. The juvenile components represent a fundamentally new magma composition for OL, containing 25-30 wt.% SiO2, with 7-11 wt.% CO2, high alkalies (Na2O 15-19%, K2O 4-5%), and trace-element signatures reminiscent of natrocarbonatite enrichments. These data define an intermediate composition between natrocarbonatite and nephelinite, with about one third natrocarbonatite and two thirds nephelinite component. The data are consistent with a model in which the carbonated silicate magma has evolved from the common combeite-wollastonite nephelinite (CWN) of OL by enrichment of CO2 and alkalies and is close to the liquid immiscible separation of natrocarbonatite from carbonated nephelinite. Material ejected in April/May 2008 indicates reversion to a more common CWN composition.

  12. An analysis of data collected from the 2007--2008 Tennessee state report card and the variables related to science test results

    NASA Astrophysics Data System (ADS)

    Lamons, Julia W.

    The purpose of this study was to determine whether Tennessee Comprehensive Assessment Program (TCAP) Achievement reading scores, school district per-pupil expenditures, school size, percentage of students qualifying for free and reduced-priced meals, and attendance were related to science TCAP test scores from the 2007-2008 school year. The data were gathered from an analysis of mean standardized test scores in reading and science of 8th graders in 67 school systems comprising 181 schools located throughout Tennessee. One hundred eighty-one schools configured grades 6 through 8 were used in this study. Only 177 schools had reported attendance available on the Tennessee Department of Education website. Pearson correlations were performed between the 8th mean grade science TCAP scores and 8th grade mean reading scores, per-pupil expenditure, school size, attendance, and the percentage of students qualifying for free and reduced-priced meals. Independent-samples t tests were conducted to evaluate whether 8th grade mean science TCAP scores and 8th grade mean reading scores varied depending on whether the school per-pupil expenditure was above or below the state average of $8,345. Independent-samples t test were also conducted to evaluate whether 8th grade mean science TCAP scores and 8th grade mean reading scores varied depending on whether the school attendance percentage was above or below the state goal of 93%. The school characteristic with the strongest association with the mean 8th grade science TCAP scores as computed by Pearson's correlation is the mean 8th grade reading TCAP scores. The values can be ranked as follows: mean 8th grade reading scores (.92) > percentage of students qualifying for free and reduced meals (-.84) > per-pupil expenditure (-.62) > attendance (.60) > school size (.23).

  13. Trends in Antifungal Drug Susceptibility of Cryptococcus neoformans Isolates Obtained through Population-Based Surveillance in South Africa in 2002-2003 and 2007-2008

    PubMed Central

    Govender, Nelesh P.; Patel, Jaymati; van Wyk, Marelize; Chiller, Tom M.; Lockhart, Shawn R.

    2011-01-01

    Cryptococcus neoformans is the most common cause of meningitis among adult South Africans with HIV infection/AIDS. Widespread use of fluconazole for treatment of cryptococcal meningitis and other HIV-associated opportunistic fungal infections in South Africa may lead to the emergence of isolates with reduced fluconazole susceptibility. MIC testing using a reference broth microdilution method was used to determine if isolates with reduced susceptibility to fluconazole or amphotericin B had emerged among cases of incident disease. Incident isolates were tested from two surveillance periods (2002-2003 and 2007-2008) when population-based surveillance was conducted in Gauteng Province, South Africa. These isolates were also tested for susceptibility to flucytosine, itraconazole, voriconazole, and posaconazole. Serially collected isolate pairs from cases at several large South African hospitals were also tested for susceptibility to fluconazole. Of the 487 incident isolates tested, only 3 (0.6%) demonstrated a fluconazole MIC of ≥16 μg/ml; all of these isolates were from 2002-2003. All incident isolates were inhibited by very low concentrations of amphotericin B and exhibited very low MICs to voriconazole and posaconazole. Of 67 cases with serially collected isolate pairs, only 1 case was detected where the isolate collected more than 30 days later had a fluconazole MIC value significantly higher than the MIC of the corresponding incident isolate. Although routine antifungal susceptibility testing of incident isolates is not currently recommended in clinical settings, it is still clearly important for public health to periodically monitor for the emergence of resistance. PMID:21444707

  14. Representation of the Auroral and Polar Ionosphere in the International Reference Ionosphere (IRI)

    NASA Technical Reports Server (NTRS)

    Bilitza, Dieter; Reinisch, Bodo

    2013-01-01

    This issue of Advances in Space Research presents a selection of papers that document the progress in developing and improving the International Reference Ionosphere (IRI), a widely used standard for the parameters that describe the Earths ionosphere. The core set of papers was presented during the 2010 General Assembly of the Committee on Space Research in Bremen, Germany in a session that focused on the representation of the auroral and polar ionosphere in the IRI model. In addition, papers were solicited and submitted from the scientific community in a general call for appropriate papers.

  15. Proceedings of the Fourth International Conference on Mars Polar Science and Exploration

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Sessions in this conference include: Mars polar geology and glaciology; Mars and terrestrial radar investigations; Observations, nature, and evolution of the Martian seasonal polar caps; Mars' residual south polar cap; Climate change, ice core analysis, and the redistribution of volatiles on Mars; errestrial Mars analog environments; The Phoenix Scout mission and the nature of the near-polar environment; Moderated Discussion: Key Issues Regarding Phoenix Scout Mission and the nature of the near-polar environment; Panel Discussion: Key Issues in Mars Polar Science and Exploration; Mars Reconnaissance Orbiter investigations of the Martian polar regions and climate; Mars Polar Scout Mission concepts; and Panel Discussion: New perspectives on Mars polar science and exploration

  16. Adolescent Crash Rates and School Start Times in Two Central Virginia Counties, 2009-2011: A Follow-up Study to a Southeastern Virginia Study, 2007-2008

    PubMed Central

    Vorona, Robert Daniel; Szklo-Coxe, Mariana; Lamichhane, Rajan; Ware, J. Catesby; McNallen, Ann; Leszczyszyn, David

    2014-01-01

    Virginia study, 2007-2008. J Clin Sleep Med 2014;10(11):1169-1177. PMID:25325600

  17. "POLAR-PALOOZA" and "International POLAR-PALOOZA": Taking Researchers on the Road to Engage Public Audiences across America, and Around the World

    NASA Astrophysics Data System (ADS)

    Haines-Stiles, G.; Akuginow, E.

    2010-12-01

    POLAR-PALOOZA and its companion project, "International POLAR-PALOOZA" shared the same central premise: that polar researchers, speaking for themselves, could be powerful communicators about the science and mission of the 4th International Polar Year, and could successfully engage a wide variety of public audiences across America and around the world. Supported for the US tour by NSF and NASA, and internationally by NSF alone, the project enlisted more than forty American researchers, and 14 polar scientists from Brazil, China and Australia, to participate in events at science centers and natural history museums, universities, public libraries and schools, and also for targeted outreach to special audiences such as young female researchers in Oklahoma, or the Downtown Rotary in San Diego. Evaluations by two different ISE groups found similar results domestically and internationally. When supported by HD video clips and presenting informally in teams of 3, 4, 5 and sometimes even 6 researchers as part of a fast-paced "show," the scientists themselves were almost always rated as among the most important aspects of the program. Significant understandings about polar science and global climate change resulted, along with a positive impression of the research undertaken during IPY. This presentation at Fall AGU 2010 will present results from the Summative Evaluation of both projects, show representative video clips of the public presentations, share photographs of some of the most dramatically varied venues and candid behind-the-scenes action, and share "Lessons Learned" that can be broadly applied to the dissemination of Earth and space science research. These include: collaboration with partner institutions is never easy. (Duh.) Authentic props (such as ice cores, when not trashed by TSA) make a powerful impression on audiences, and give reality to remote places and complex science. And, most importantly, that since 85% of Americans have never met a scientist, that

  18. International Polar Year Information Resources: Science Librarians Behind the Scenes and in the Field

    NASA Astrophysics Data System (ADS)

    Hicks, G. J.; Sommer, S.

    2006-12-01

    As the International Polar Year approaches, research institutes, scientists, and students are preparing for the challenges of field research and the resulting reports and papers. In support of these researchers, libraries and information centers are developing programs and special projects to provide the information and repositories vital to dissemination of the resulting data and reports. From the National Snow and Ice Data Center's DAHLI project to Scott Polar Research Institute's Discovering the Poles, polar science librarians around the world are gearing up to provide service and information to researchers at home and in the field. Not only will these information specialists and librarians provide resources or answer questions for the scientist in the office, they will also provide much of those same services to the researcher in the field. IPY resources are a special case of the on-demand services science librarians typically provide. They help scientists formulate search strategies and take advantage of new developments in scientific databases at their home institutes. They provide many of the same services to researchers in the field. Whether sitting on an ice breaker in the Southern Ocean or in a tent on a glacier in Spitsbergen, field scientists can email or IM a question to a librarian for digital copies of papers, answers to reference questions, or information from a source in the office. IPY data and publications will be distributed among many existing and a few new clearinghouses and article databases. Science librarians will ensure that their researchers can locate and use these resources, providing a vital service and many important resources for this global effort to understand the current status of climate change and its effect around the globe.

  19. POLAR-PALOOZA Polar Researchers and Arctic Residents Engage, Inform and Inspire Diverse Public Audiences by sharing Polar Science and Global Connections during the International Polar Year, using a New Model of Informal Science Education

    NASA Astrophysics Data System (ADS)

    Haines-Stiles, G.; Akuginow, E.

    2006-12-01

    (Please note that the POLAR-PALOOZA initiative described in this Abstract is-as of 9/7/2006-"pending" for possible support from NSF and NASA as part of this year's IPY solicitation. Subject to decisions expected by 9/30, this presentation would either be withdrawn, or amplified with specific participants, locations and dates.) Despite the success of well-regarded movies like "March of the Penguins", the polar regions remain a great unknown for most people. Public knowledge about the Arctic and Antarctic, and the critical role of the Poles in the entire Earth system, is nonexistent, incomplete or burdened with misperceptions. The International Polar Years of 2007-2009-and associated "I*Y" science years such as IHY, IYPE and eGY-present a unique opportunity to change this. The people who can best effect this change are those who know the Poles best, through living or working there. Based on innovative but proven models, POLAR-PALOOZA will use three complementary strategies to engage, inform and inspire large public audiences. (1) A national tour, under the working title "Stories from a Changing Planet", will include in-person presentations at science centers, museums, libraries and schools across North America, including Canada and Mexico. The presentations will be augmented by High Definition Video taped on location at the Poles, audio and video podcasts, and special education and outreach activities for targeted audiences. "Stories from a Changing Planet" will provide diverse audiences with an exciting opportunity to meet and interact directly with polar experts, and to appreciate why the Poles and the research done there are directly relevant to their lives. (2) The "HiDef Video Science Story Capture Corps" is a team of professional videographers, using the latest generation of low-cost, high-quality cameras, deployed to both Poles. They will document the work of multiple researchers and projects, rather than focusing on one topic for a single broadcast program

  20. Hydrophilic Mineral Coating of Membrane Substrate for Reducing Internal Concentration Polarization (ICP) in Forward Osmosis

    NASA Astrophysics Data System (ADS)

    Liu, Qing; Li, Jingguo; Zhou, Zhengzhong; Xie, Jianping; Lee, Jim Yang

    2016-01-01

    Internal concentration polarization (ICP) is a major issue in forward osmosis (FO) as it can significantly reduce the water flux in FO operations. It is known that a hydrophilic substrate and a smaller membrane structure parameter (S) are effective against ICP. This paper reports the development of a thin film composite (TFC) FO membrane with a hydrophilic mineral (CaCO3)-coated polyethersulfone (PES)-based substrate. The CaCO3 coating was applied continuously and uniformly on the membrane pore surfaces throughout the TFC substrate. Due to the intrinsic hydrophilicity of the CaCO3 coating, the substrate hydrophilicity was significantly increased and the membrane S parameter was reduced to as low as the current best of cellulose-based membranes but without the mechanical fragility of the latter. As a result, the ICP of the TFC-FO membrane could be significantly reduced to yield a remarkable increase in water flux without the loss of membrane selectivity.

  1. A half century perspective on the International Geophysical Year (IGY) - A Template for the International Polar Year 2007 (IPY 2007)?

    NASA Astrophysics Data System (ADS)

    Behrendt, J. C.

    2003-12-01

    In 1956 I sailed for Antarctica to spend 18 months as a graduate student participating in geophysical-glaciological investigations, as part of the 18-month IGY. This led to a career in geophysics, which has taken me to all of the continents and oceans. As we approach the IPY 2007, the changes in technology and our understanding of the earth over the past half century are breathtaking to contemplate. Although 70 countries participated in IGY, the disciplines were restricted to geophysics. Originally the Third Polar Year, the name was changed to IGY in 1952, at the suggestion of Sydney Chapman. The geographical area comprised the entire earth. The highest priority was given to "problems requiring concurrent synoptic observations at many points involving cooperative observations by many stations." One category was reserved for research on topics such as ocean levels, weather patterns, and the distribution of glacier ice "to establish basic information for subsequent comparison at later epochs." IPY 2007 seems such an epoch. A major international efforts was concentrated in Antarctica, although only 12 counties participated. Glaciology, seismology, auroral studies, ionospheric soundings, magnetic field measurements, and other solar-terrestrial, and meteorological observations comprised the scientific station activities. The only major field activities away from the stations were the oversnow geophysical-glaciological traverses, which made seismic measurements of ice thickness and other ice properties; gravity and magnetic anomaly profiles; and determination of snow accumulation and mean annual temperature. The most intensive of the oversnow traverse programs were those of the U.S. and USSR. Geology and topographic mapping were excluded from the Antarctica because of potential complications due to territorial claims and the possibility of mineral resource discoveries. Despite this, significant geologic findings, such as the discovery of the Dufek intrusion, were made by

  2. ESSEA K-4 Online Course: Polar Connections

    NASA Astrophysics Data System (ADS)

    Blaney, L.; Myers, R. J.; Schwerin, T.

    2007-12-01

    . Changes in climate, air, water, and land quality and animal and plant populations make the news everyday. The K-4 course will help teachers inform rather than frighten their students as they learn more about the characteristics and importance of our polar regions. One goal of IPY 2007-2008 is to increase the awareness, understanding and interest of school-age children in polar conditions and research. The inclusion of polar topics in the K-4 course contributes to the achievement of that goal.

  3. Multiresolution internal template cleaning: an application to the Wilkinson Microwave Anisotropy Probe 7-yr polarization data

    NASA Astrophysics Data System (ADS)

    Fernández-Cobos, R.; Vielva, P.; Barreiro, R. B.; Martínez-González, E.

    2012-03-01

    The cosmic microwave background (CMB) radiation data obtained by different experiments contain, besides the desired signal, a superposition of microwave sky contributions. Using a wavelet decomposition on the sphere, we present a fast and robust method to recover the CMB signal from microwave maps. We present an application to the Wilkinson Microwave Anisotropy Probe (WMAP) polarization data, which shows its good performance, particularly in very polluted regions of the sky. The applied wavelet has the advantages that it requires little computational time in its calculations, it is adapted to the HEALPIX pixelization scheme and it offers the possibility of multiresolution analysis. The decomposition is implemented as part of a fully internal template fitting method, minimizing the variance of the resulting map at each scale. Using a χ2 characterization of the noise, we find that the residuals of the cleaned maps are compatible with those expected from the instrumental noise. The maps are also comparable to those obtained from the WMAP team, but in our case we do not make use of external data sets. In addition, at low resolution, our cleaned maps present a lower level of noise. The E-mode power spectrum ? is computed at high and low resolutions, and a cross-power spectrum ? is also calculated from the foreground reduced maps of temperature given by WMAP and our cleaned maps of polarization at high resolution. These spectra are consistent with the power spectra supplied by the WMAP team. We detect the E-mode acoustic peak at ℓ˜ 400, as predicted by the standard ΛCDM model. The B-mode power spectrum ? is compatible with zero.

  4. Educational and Community Outreach Efforts by the United States Polar Rock Repository during the International Polar Year

    NASA Astrophysics Data System (ADS)

    Grunow, A.; Codispoti, J. E.

    2010-12-01

    The US Polar Rock Repository (USPRR) houses more than 19,000 rock samples from polar regions and these samples are made available to the scientific, educational and museum community. The USPRR has been active in promoting polar earth science to educational and community groups. During the past year, outreach efforts reached over 12,000 people. The USPRR outreach involve tours of the facility, school presentations, online laboratory exercises, working with the Columbus Metro Parks, teaching at summer camps, teaching special geology field assignments at the middle school level, as well as offering an ‘Antarctic Rock Box’ that contains representative samples of the three types of rocks, minerals, fossils, and books and activities about geology and Antarctica. The rock box activities have been designed and reviewed by educators and scientists to use as an educational supplement to the Earth Science course of study. The activities have been designed around the Academic Content Standards: k-12 Science manual published by the Ohio Department of Education to ensure that the activities and topics are focused on those mandated by the state of Ohio. The USPRR website has a Virtual Web Antarctic Expedition with many activities for Middle to High School age students. The students learn about how to plan a field season, safety techniques, how to make a remote field camp, identify what equipment is needed, learn about the different transportation choices, weather issues, understanding GPS, etc. Educational and community networks have been built in part, by directly contacting individuals at an institution and partnering with them on educational outreach. The institutions have been very interested in doing this because it brings scientists to the classroom and to the public. This type of outreach has also served as an opening for children to consider possible career choices in science that they may not have considered before. In many of the presentations, a female geologist

  5. Scientists as Correspondents: Exploratorium "Ice Stories" for International Polar Year Project Educational Outreach

    NASA Astrophysics Data System (ADS)

    McGillivary, P. A.; Fall, K. R.; Miller, M.; Higdon, R.; Andrews, M.; O'Donnell, K.

    2008-12-01

    As part of the 2007-2009 International Polar Year (IPY), an educational outreach developed by the Exploratorium science museum of San Francisco builds on prior high latitude programs to: 1) create public awareness of IPY research; 2) increase public understanding of the scientific process; and, 3) stimulate a new relationship between scientists and outreach. Funded by the National Science Foundation, a key "Ice Stories" innovation is to facilitate "scientist correspondents" reporting directly to the public. To achieve this, scientists were furnished multimedia equipment and training to produce material for middle school students to adults. Scientists submitted blogs of text, images, and video from the field which were edited, standardized for format, and uploaded by Exploratorium staff, who coordinated website content and management. Online links to educational partner institutions and programs from prior Exploratorium high latitude programs will extend "Ice Stories" site visits beyond the @250,000 unique in-house users/year to more than 28 million webpage users/year overall. We review relevant technical issues, the variety of scientist participation, and what worked best and recommendations for similar efforts in the future as a legacy for the IPY.

  6. Autoregressive harmonic analysis of the earth's polar motion using homogeneous International Latitude Service data

    NASA Technical Reports Server (NTRS)

    Chao, B. F.

    1983-01-01

    The homogeneous set of 80-year-long (1900-1979) International Latitude Service (ILS) polar motion data is analyzed using the autoregressive method (Chao and Gilbert, 1980), which resolves and produces estimates for the complex frequency (or frequency and Q) and complex amplitude (or amplitude and phase) of each harmonic component in the data. The ILS data support the multiple-component hypothesis of the Chandler wobble. It is found that the Chandler wobble can be adequately modeled as a linear combination of four (coherent) harmonic components, each of which represents a steady, nearly circular, prograde motion. The four-component Chandler wobble model 'explains' the apparent phase reversal during 1920-1940 and the pre-1950 empirical period-amplitude relation. The annual wobble is shown to be rather stationary over the years both in amplitude and in phase, and no evidence is found to support the large variations reported by earlier investigations. The Markowitz wobble is found to be marginally retrograde and appears to have a complicated behavior which cannot be resolved because of the shortness of the data set.

  7. Hydrophilic Mineral Coating of Membrane Substrate for Reducing Internal Concentration Polarization (ICP) in Forward Osmosis

    PubMed Central

    Liu, Qing; Li, Jingguo; Zhou, Zhengzhong; Xie, Jianping; Lee, Jim Yang

    2016-01-01

    Internal concentration polarization (ICP) is a major issue in forward osmosis (FO) as it can significantly reduce the water flux in FO operations. It is known that a hydrophilic substrate and a smaller membrane structure parameter (S) are effective against ICP. This paper reports the development of a thin film composite (TFC) FO membrane with a hydrophilic mineral (CaCO3)-coated polyethersulfone (PES)-based substrate. The CaCO3 coating was applied continuously and uniformly on the membrane pore surfaces throughout the TFC substrate. Due to the intrinsic hydrophilicity of the CaCO3 coating, the substrate hydrophilicity was significantly increased and the membrane S parameter was reduced to as low as the current best of cellulose-based membranes but without the mechanical fragility of the latter. As a result, the ICP of the TFC-FO membrane could be significantly reduced to yield a remarkable increase in water flux without the loss of membrane selectivity. PMID:26796675

  8. Hydrophilic Mineral Coating of Membrane Substrate for Reducing Internal Concentration Polarization (ICP) in Forward Osmosis.

    PubMed

    Liu, Qing; Li, Jingguo; Zhou, Zhengzhong; Xie, Jianping; Lee, Jim Yang

    2016-01-01

    Internal concentration polarization (ICP) is a major issue in forward osmosis (FO) as it can significantly reduce the water flux in FO operations. It is known that a hydrophilic substrate and a smaller membrane structure parameter (S) are effective against ICP. This paper reports the development of a thin film composite (TFC) FO membrane with a hydrophilic mineral (CaCO3)-coated polyethersulfone (PES)-based substrate. The CaCO3 coating was applied continuously and uniformly on the membrane pore surfaces throughout the TFC substrate. Due to the intrinsic hydrophilicity of the CaCO3 coating, the substrate hydrophilicity was significantly increased and the membrane S parameter was reduced to as low as the current best of cellulose-based membranes but without the mechanical fragility of the latter. As a result, the ICP of the TFC-FO membrane could be significantly reduced to yield a remarkable increase in water flux without the loss of membrane selectivity. PMID:26796675

  9. Crystallographic Study of Hydration of an Internal Cavity in Engineered Proteins with Buried Polar or Ionizable Groups

    PubMed Central

    Schlessman, Jamie L.; Abe, Colby; Gittis, Apostolos; Karp, Daniel A.; Dolan, Michael A.; García-Moreno E., Bertrand

    2008-01-01

    Although internal water molecules are essential for the structure and function of many proteins, the structural and physical factors that govern internal hydration are poorly understood. We have examined the molecular determinants of internal hydration systematically, by solving the crystal structures of variants of staphylococcal nuclease with Gln-66, Asn-66, and Tyr-66 at cryo (100 K) and room (298 K) temperatures, and comparing them with existing cryo and room temperature structures of variants with Glu-66, Asp-66, Lys-66, Glu-92 or Lys-92 obtained under conditions of pH where the internal ionizable groups are in the neutral state. At cryogenic temperatures the polar moieties of all these internal side chains are hydrated except in the cases of Lys-66 and Lys-92. At room temperature the internal water molecules were observed only in variants with Glu-66 and Tyr-66; water molecules in the other variants are probably present but they are disordered and therefore undetectable crystallographically. Each internal water molecule establishes between 3 and 5 hydrogen bonds with the protein or with other internal water molecules. The strength of interactions between internal polar side chains and water molecules seems to decrease from carboxylic acids to amides to amines. Low temperature, low cavity volume, and the presence of oxygen atoms in the cavity increase the positional stability of internal water molecules. This set of structures and the physical insight they contribute into internal hydration will be useful for the development and benchmarking of computational methods for artificial hydration of pockets, cavities, and active sites in proteins. PMID:18178652

  10. Role of flagella in adherence, internalization, and translocation of Campylobacter jejuni in nonpolarized and polarized epithelial cell cultures.

    PubMed Central

    Grant, C C; Konkel, M E; Cieplak, W; Tompkins, L S

    1993-01-01

    Previous studies of Campylobacter jejuni have suggested that flagellin is an adhesin for epithelial cells and that motility is a virulence factor of this bacterium. The role of flagella in the interactions of C. jejuni with nonpolarized and polarized epithelial cells was examined with flagellar mutants. Flagellated, nonmotile (flaA flaB+ Mot-) and nonflagellated, nonmotile (flaA flaB Mot-) mutants of C. jejuni were constructed by in vivo homologous recombination and gene replacement techniques. Both classes of mutants were found to adhere to cells of human epithelial origin (INT 407) equally well; however, on the basis of the percentage of the inoculum internalized, internalization of the flaA flaB Mot- mutants was decreased by factors ranging from approximately 30 to 40 compared with the parent. The flaA flaB+ Mot- mutant was internalized by the INT 407 cells at levels six- to sevenfold higher than the flaA flaB Mot- mutants. Both classes of mutants, unlike the parent, were unable to translocate across polarized Caco-2 monolayers. These results indicate that flagella are not involved in C. jejuni adherence to epithelial cells but that they do play a role in internalization. Furthermore, the results suggest that either the motility of C. jejuni or the product of flaA is essential for the bacterium to cross polarized epithelial cell monolayers. Images PMID:8478066

  11. Role of Flexibility and Polarity as Determinants of the Hydration of Internal Cavities and Pockets in Proteins

    PubMed Central

    Damjanović, Ana; Schlessman, Jamie L.; Fitch, Carolyn A.; García, Angel E.; García-Moreno E., Bertrand

    2007-01-01

    Molecular dynamics simulations of Staphylococcal nuclease and of 10 variants with internal polar or ionizable groups were performed to investigate systematically the molecular determinants of hydration of internal cavities and pockets in proteins. In contrast to apolar cavities in rigid carbon structures, such as nanotubes or buckeyballs, internal cavities in proteins that are large enough to house a few water molecules will most likely be dehydrated unless they contain a source of polarity. The water content in the protein interior can be modulated by the flexibility of protein elements that interact with water, which can impart positional disorder to water molecules, or bias the pattern of internal hydration that is stabilized. This might explain differences in the patterns of hydration observed in crystal structures obtained at cryogenic and room temperature conditions. The ability of molecular dynamics simulations to determine the most likely sites of water binding in internal pockets and cavities depends on its efficiency in sampling the hydration of internal sites and alternative protein and water conformations. This can be enhanced significantly by performing multiple molecular dynamics simulations as well as simulations started from different initial hydration states. PMID:17604315

  12. Internal Structure of the North Polar Layered Deposits on Mars From SHARAD Observations

    NASA Astrophysics Data System (ADS)

    Putzig, N. E.; Holt, J. W.; Phillips, R. J.; Seu, R.; Biccari, D.; Campbell, B. A.; Carter, L. M.; Safaeinili, A.; Egan, A. F.

    2007-12-01

    The Shallow Radar (SHARAD) instrument onboard the Mars Reconnaissance Orbiter is revealing detailed layering patterns within the North Polar Layered Deposits (NPLD) in Planum Boreum. Since the beginning of its primary science mission in November of 2006, SHARAD has acquired over 400 subsurface sounding observations (radargrams) that cross the NPLD. Each radargram consists of a two-dimensional profile beneath the instrument's ground track and shows a series of returns corresponding to dielectric contrasts in the subsurface to depths of 2 to 3 km. We have imported a subset of these data together with associated location information into an interactive subsurface data interpretation software package, thereby allowing us to delineate and map horizons and faults within the NPLD in three dimensions. Our initial results show: 1) several discrete units of sub-parallel reflections separated by regional unconformities and situated above a diffusely reflective zone (DRZ) that extends throughout the main lobe of the NPLD and appears to correspond to a previously identified Basal Unit (Byrne and Murray 2002, JGR 107 E6, 5044); 2) apparent large-scale faulting or imbrication of the DRZ in portions of the main lobe to the east of Chasma Boreale; 3) the absence of the distinct basal reflections beneath the main lobe and Olympia Planum that have been identified in MARSIS results (Picardi et al. 2005, Science 310, #5756, pp. 1925-1928; Phillips et al. 2007, LPSC XXXVIII, Abstract 1925); and 4) shallow subsurface layering in portions of Olympia Planum that are proximal to the main lobe. These findings have significant implications for the history of accumulation and erosion of the NPLD, which may provide a record of the global climate history for much of the Amazonian epoch. Efforts to correlate the internal units unveiled by SHARAD with those mapped on the basis of images and other surface data are in progress. Acknowledgments: Thanks to the Italian Space Agency (ASI) and NASA/JPL.

  13. Detection of internally mixed Asian dust with air pollution aerosols using a polarization optical particle counter and a polarization-sensitive two-wavelength lidar

    NASA Astrophysics Data System (ADS)

    Sugimoto, Nobuo; Nishizawa, Tomoaki; Shimizu, Atsushi; Matsui, Ichiro; Kobayashi, Hiroshi

    2015-01-01

    East Asia is a unique region where mineral dust (Asian dust) sources are located near urban and industrial areas. Asian dust is often mixed with air pollution aerosols during transportation. It is important to understand the mixing states of Asian dust and other aerosols, because the effects on the environment and human health differ depending on the mixing state. We studied the mixing states of Asian dust using a polarization particle counter (POPC) that measures the forward scattering and the two polarization components of backscattering for single particles and a polarization-sensitive (532 nm) two-wavelength (1064 nm and 532 nm) lidar. We conducted the simultaneous observations using the POPC and the lidar in Seoul from March to December 2013 and captured the characteristics of pure Asian dust and internally mixed polluted Asian dust. POPC measurements indicated that the density of large particles was lower in polluted Asian dust that transported slowly over the polluted areas than in pure Asian dust that transported quickly from the dust source region. Moreover, the backscattering depolarization ratio was smaller for all particle sizes in polluted dust. The optical characteristics measured using the lidar were consistent with the POPC measurements. The backscattering color ratio of polluted dust was comparable to that of pure dust, but the depolarization ratio was lower for polluted dust. In addition, coarse non-spherical particles (Asian dust) almost always existed in the background, and the depolarization ratio had seasonal variation with a lower depolarization ratio in the summer. These results suggest background Asian dust particles are internally mixed in the summer.

  14. Probing Membrane Order and Topography in Supported Lipid Bilayers by Combined Polarized Total Internal Reflection Fluorescence-Atomic Force Microscopy

    PubMed Central

    Oreopoulos, John; Yip, Christopher M.

    2009-01-01

    Determining the local structure, dynamics, and conformational requirements for protein-protein and protein-lipid interactions in membranes is critical to understanding biological processes ranging from signaling to the translocating and membranolytic action of antimicrobial peptides. We report here the application of a combined polarized total internal reflection fluorescence microscopy-in situ atomic force microscopy platform. This platform's ability to image membrane orientational order was demonstrated on DOPC/DSPC/cholesterol model membranes containing the fluorescent membrane probe, DiI-C20 or BODIPY-PC. Spatially resolved order parameters and fluorophore tilt angles extracted from the polarized total internal reflection fluorescence microscopy images were in good agreement with the topographical details resolved by in situ atomic force microscopy, portending use of this technique for high-resolution characterization of membrane domain structures and peptide-membrane interactions. PMID:19254557

  15. The Arctic Human Health Initiative: a legacy of the International Polar Year 2007–2009

    PubMed Central

    Parkinson, Alan J.

    2013-01-01

    Background The International Polar Year (IPY) 2007–2008 represented a unique opportunity to further stimulate cooperation and coordination on Arctic health research and increase the awareness and visibility of Arctic regions. The Arctic Human Health Initiative (AHHI) was a US-led Arctic Council IPY coordinating project that aimed to build and expand on existing International Union for Circumpolar Health (IUCH) and Arctic Council human health interests. The project aimed to link researchers with potential international collaborators and to serve as a focal point for human health research, education, outreach and communication activities during the IPY. The progress of projects conducted as part of this initiative up until the end of the Arctic Council Swedish chairmanship in May 2013 is summarized in this report. Design The overall goals of the AHHI was to increase awareness and visibility of human health concerns of Arctic peoples, foster human health research, and promote health strategies that will improve health and well-being of all Arctic residents. Proposed activities to be recognized through the initiative included: expanding research networks that will enhance surveillance and monitoring of health issues of concern to Arctic peoples, and increase collaboration and coordination of human health research; fostering research that will examine the health impact of anthropogenic pollution, rapid modernization and economic development, climate variability, infectious and chronic diseases, intentional and unintentional injuries, promoting education, outreach and communication that will focus public and political attention on Arctic health issues, using a variety of publications, printed and electronic reports from scientific conferences, symposia and workshops targeting researchers, students, communities and policy makers; promoting the translation of research into health policy and community action including implementation of prevention strategies and health

  16. Internal spin structure of the proton from high energy polarized e-p scattering

    SciTech Connect

    Hughes, V.W.; Baum, G.; Bergstroem, M.R.

    1981-02-01

    A review is given of experimental knowledge of the spin dependent structure functions of the proton, which is based on inclusive high energy scattering of longitudinal polarized electrons by longitudinally polarized protons in both the deep inelastic and resonance regions, and includes preliminary results from our most recent SLAC experiment. Implications for scaling, sum rules, models of proton structure, and the hyperfine structure interval in hydrogen are given. Possible future directions of research are indicated.

  17. Socio-Pedagogical Challenges Facing Orphaned and Vulnerable Children in the Aftermath of the 2007-2008 Election Violence in Nakuru County, Kenya

    ERIC Educational Resources Information Center

    Majanga, Eunice; Mukonyi, Phillip; Vundi, Silvia

    2015-01-01

    The conflict situations that have afflicted parts of Kenya every five years, in the wake of general elections, since 1992 were most prominent after the disputed presidential elections of 2007. The magnitude of the clashes, loss of life, destruction of property and internal displacement of people were hitherto unwitnessed. The situation of Orphans…

  18. CTEPP STANDARD OPERATING PROCEDURE FOR PREPARATION OF SURROGATE RECOVERY STANDARD AND INTERNAL STANDARD SOLUTIONS FOR POLAR TARGET ANALYTES (SOP-5.26)

    EPA Science Inventory

    This SOP describes the method used for preparing surrogate recovery standard and internal standard solutions for the analysis of polar target analytes. It also describes the method for preparing calibration standard solutions for polar analytes used for gas chromatography/mass sp...

  19. Abstracts: International conference on the role of the polar regions in global change

    SciTech Connect

    Not Available

    1991-01-01

    The objective of this conference was to summarize the state of knowledge on the role of the polar regions in global change, and to identify gaps in our knowledge. Polar experts in a wide variety of disciplines shared their knowledge and their experiences on global change. Topics included: detection and monitoring of change; climate variability and climate forcing; ocean-sea ice-atmosphere interactions and processes; effects on biota and biological feedbacks; ice sheet, glacier and permafrost responses and feedbacks; paleoenvironmental studies; and aerosols/trace gases. Individual papers have been processed for inclusion in the appropriate data bases.

  20. Internal wave activity in the polar atmospheric regions during 2006 - 2009 revealed by COSMIC radio occultation data

    NASA Astrophysics Data System (ADS)

    Kirillovich, Ivan; Gubenko, Vladimir; Pavelyev, Alexander; Liou, Yuei-An

    The satellite mission Formosat-3/COSMIC (Constellation Observing System for Meteorology, Ionosphere and Climate) consists of six micro-satellites, and each of them has four GPS-antennas. It was launched in April 2006, orbiting around the Earth at approximately 800 km. The primary scientific goal of the mission is to demonstrate the value of near-real-time radio occultation (RO) observations in improving operational numerical weather predictions (NWP). The goal is readily shown by assimilating the measurements of atmospheric parameters into used NWP-models. These parameters include density, temperature, pressure and relative humidity fields in the atmosphere. An analysis of their geographic and seasonal distributions is necessary to the understanding of the energy and momentum transfer and the reaction of the polar atmosphere in response to global warming. This task is especially important as the Polar Regions are very sensitive to the change in global temperature and it may be a major cause of global sea level rising. In this work, a statistical analysis of the internal gravity wave (IGW) activity in polar atmospheric regions (latitudes more than 60º) using Formosat-3/COSMIC RO temperature data collected from July 2006 to March 2009 has been performed. Geographic and seasonal distributions of the IGW potential energy (wave activity indicator) in the altitude interval from 15 to 35 km have been determined and analyzed. The obtained results show that the wave activity in the polar atmosphere is strong in winter and spring. The potential energy of IGWs in spring is largest in Antarctic atmospheric region, while it is largest in winter in Arctic region. The wave potential energy increases with altitude up to 35 km in the atmosphere of both Earth’s hemispheres. In Antarctic region, internal waves with high potential energy occur in the atmosphere over the Antarctic Peninsula. In Arctic region, a high wave activity is mainly observed over North Atlantic Ocean (Iceland

  1. Long-term accumulation and improvements in seismic event data for the polar regions by the International Seismological Centre

    NASA Astrophysics Data System (ADS)

    Storchak, Dmitry A.; Kanao, Masaki; Delahaye, Emily; Harris, James

    2015-03-01

    The International Seismological Centre (ISC) is a non-governmental non-profit making organization funded by 62 research and operational institutions around the world and charged with the production of the ISC Bulletin - the definitive summary of the global seismicity based on reports from over 130 agencies worldwide, including those active in Polar regions. Jointly with the National Earthquake Information Center (NEIC) of the United States Geological Survey (USGS), the ISC runs the International Seismic Station Registry. The ISC is also charged with maintaining the International Association of Seismology and Physics of the Earth Interior (IASPEI) Reference event List. The new ISC product, the ISC Event Bibliography allows users to obtain references to scientific articles describing specific seismic events, natural and anthropogenic. In this paper we demonstrate how these products and services are applicable to seismic events both in Arctic and Antarctic regions. We also give a summary of the ISC data in polar regions and provide credit to Institutions that report these data to the ISC.

  2. Microbiological and ecological responses to global environmental changes in polar regions (MERGE): An IPY core coordinating project

    NASA Astrophysics Data System (ADS)

    Naganuma, Takeshi; Wilmotte, Annick

    2009-11-01

    An integrated program, “Microbiological and ecological responses to global environmental changes in polar regions” (MERGE), was proposed in the International Polar Year (IPY) 2007-2008 and endorsed by the IPY committee as a coordinating proposal. MERGE hosts original proposals to the IPY and facilitates their funding. MERGE selected three key questions to produce scientific achievements. Prokaryotic and eukaryotic organisms in terrestrial, lacustrine, and supraglacial habitats were targeted according to diversity and biogeography; food webs and ecosystem evolution; and linkages between biological, chemical, and physical processes in the supraglacial biome. MERGE hosted 13 original and seven additional proposals, with two full proposals. It respected the priorities and achievements of the individual proposals and aimed to unify their significant results. Ideas and projects followed a bottom-up rather than a top-down approach. We intend to inform the MERGE community of the initial results and encourage ongoing collaboration. Scientists from non-polar regions have also participated and are encouraged to remain involved in MERGE. MERGE is formed by scientists from Argentina, Australia, Austria, Belgium, Brazil, Bulgaria, Canada, Egypt, Finland, France, Germany, Italy, Japan, Korea, Malaysia, New Zealand, Philippines, Poland, Russia, Spain, UK, Uruguay, USA, and Vietnam, and associates from Chile, Denmark, Netherlands, and Norway.

  3. Daytime Polar Alignment of Telescope Mountings Using GPS and Internal Reference Optics

    NASA Astrophysics Data System (ADS)

    Mellon, R. R.; Scheld, D.; Stencel, R. E.

    1998-12-01

    A technique is presented for performing polar alignment of astronomical telescope mountings to high precision during daylight hours. This work originated in the requirement to erect a truck mounted astronomical telescope at multiple locations during the day in order to measure the atmospheric convective turbulence Fried Parameter r0 by tracking stars at various zenith angles. The custom equatorial mounting built for this project incorporates a surveyor's theodolite, which is used to establish an optical line of sight to the North Celestial Pole (NCP). The elevation angle of this line of sight is set directly by adjusting the theodolite tube elevation angle to that of the local geographic latitude obtained from a Global Positioning System (GPS) receiver. The theodolite is set into the azimuth of the Pole by observing an object on the horizon of known bearing angle or by observing the Sun=92s known azimuth at a specified time. Once the theodolite line of sight to the NCP is established, an optical target projector contained within and aligned with the polar axis provides an illuminated pattern, which is viewed by the theodolite. Subsequent adjustments of the elevation and azimuth of the polar axis bring the projected pattern onto the intersection of the crosshairs in the theodolite reticule, thereby bringing the polar axis into close coincidence with the NCP. Denver University astronomers are interested in this application for their proposed Fully Adaptive Segmented Telescope (FAST) instrument, a meter-class instrument which can be transported among high altitude sites (see www. adaptive-optics.com). Equinox Interscience (303-843-0313) can provide this daytime polar alignment capability to interested users for equatorial mountings.

  4. Development of a cross-polarization scattering system for the measurement of internal magnetic fluctuations in the DIII-D tokamak

    SciTech Connect

    Rhodes, T. L. Peebles, W. A.; Crocker, N. A.; Nguyen, X.

    2014-11-15

    The design and performance of a new cross-polarization scattering (CPS) system for the localized measurement of internal magnetic fluctuations is presented. CPS is a process whereby magnetic fluctuations scatter incident electromagnetic radiation into a perpendicular polarization which is subsequently detected. A new CPS design that incorporates a unique scattering geometry was laboratory tested, optimized, and installed on the DIII-D tokamak. Plasma tests of signal-to-noise, polarization purity, and frequency response indicate proper functioning of the system. CPS data show interesting features related to internal MHD perturbations known as sawteeth that are not observed on density fluctuations.

  5. Investigation of water-containing inverted micelles by fluorescence polarization determination of size and internal fluidity

    SciTech Connect

    Keh, E.; Valeur, B.

    1981-02-01

    Water-containing inverted micelles of sodium di(2-ethylhexyl) sulfosuccinate (AOT) have been investigated by fluorescence polarization using fluorescent hydrophilic probes localized in the aqueous core of the micelles. Measurements of the stationary polarization in two apolar solvents of different viscosity but of the same chemical nature permit rapid determination of both micellar hydrodynamic volume and water pool fluidity as a function of water content up to (H/sub 2/O)/(AOT) = 11. The characteristics of AOT micelles appear to be unchanged in the n-alkane series from hexane to dodecane and slightly affected in various apolar solvents. Solvents of high polarizability such as benzene, toluene, and carbon tetrachloride penetrate into the amphiphile layer, presumably up to the water core boundary. No significant effect of sodium chloride was observed up to a concentration of 0.4 M. The inverse micelle size is independent of surfactant concentration below 0.3 M.

  6. Arctic Expedition of the Frozen Five: an Alternative way of Education and Outreach During the International Polar Year

    NASA Astrophysics Data System (ADS)

    Senger, K.; Björkman, M.; Garny, H.; Girard, L.; Lichteneger, J.

    2006-12-01

    In March 2007, a group of international students of the geosciences will embark on a two month expedition across the wilderness of Svalbard. The journey will involve traversing up to 1000 km of high Arctic glaciers between 76° an 80°N, reaching both the southernmost and northernmost capes of Spitsbergen, Svalbard's largest island. We expect to be frequently camping at -30°C, as well as having a high probability of encountering polar bears, crevasses and arctic storms during the expedition. Through this expedition, we wish to promote the multi-disciplinary approach required in successful Arctic science. Our team, young and energetic, has already demonstrated a strong research interest in the Arctic and is ready to share their passion with the general public. Presentations by the various team members focus on the enhanced climate change and related processes witnessed at high latitudes. The concept of alternative energy, including solar power and kites used while en route, is given a high priority throughout. Here we present the education and outreach framework of the project, as well as introducing the research background of the team. We highlight current progress on the integration of this expedition in high schools around the world. The Frozen Five expedition runs in close collaboration with New Zealand's Youth Steering Committee, a major IPY project, aiming to network young polar researchers and promote the study of the polar regions to potential scientists.

  7. Evaluation of the impact of SO₂ and NO₂ emissions on the ambient air-quality in the Çan-Bayramiç region of northwest Turkey during 2007-2008.

    PubMed

    Ozkurt, Nesimi; Sari, Deniz; Akalin, Nuray; Hilmioglu, Bilgin

    2013-07-01

    The characterization and assessment of air-quality in this region are essential steps for the implementation of the "Clean Air Action Plan" as this is set by the Turkish Regulation on Ambient Air-Quality Assessment and Management. This study area intends to shed a light on use of modeling tools as an alternative method for the assessment of local atmospheric pollution and the determination of the importance of local emissions. This modeling approach can be also used for the consistent geographic representation of air-quality concentration as well as for assessing the future air-quality condition after the implementation of emission reduction measures in a certain area. With this article we evaluate the impact of sulfur dioxide and nitrogen dioxide emissions on the ambient air-quality in the Çan-Bayramiç region of Turkey. The emission rates of sulfur dioxide and nitrogen dioxide were calculated by using the CALPUFF model. The concentration of these pollutants had also been monitored at ten air-quality locations during 2007-2008 in the research area. The measured data were also utilized for testing the model performance. Results showed that the air-quality in this important rural region of Turkey can be evaluated effectively by using the current numerical modeling system. PMID:23602979

  8. Toward More Effective Comparison of Measured and Modeled Ionospheric Data Using Madrigal During the International Polar Year

    NASA Astrophysics Data System (ADS)

    Rideout, W.; Holt, J. M.; van Eyken, A. P.; Heinselman, C.

    2007-12-01

    The International Polar Year is associated with an unprecedented increase in the measurement and modeling of the polar ionosphere. This has opened the opportunity to dramatically improve the quality of the models and the underlying physical understanding, allowing improved now-casting and forecasting of the ionosphere. The Madrigal database is the traditional database used for distributing upper atmospheric data, and is used by all the incoherent scatter radar sites. The Madrigal database has also been shown to be an effective tool for distributing modeling data. One critical issue in improving models through comparison with measurements is the non-standard data products presently used by the varying incoherent scatter radars. While the parameters measured are standard, the spatial and temporal cadences of the measurements often vary widely, even for a given incoherent scatter radar. While there are various technical and scientific reasons for these variations, they do make the comparison to model runs much more difficult. In this work we discuss a higher level data product that all incoherent scatter radars can produce. This higher level product would not contain all the information in the standard products of each incoherent scatter radar, but should include all the capabilities shared by all the radars. Our experience developing a prototype of such a data product here at Millstone Hill will be discussed, along with a discussion of how this higher level data product can be distributed via the Madrigal database and more easily compared with model runs.

  9. Orientation and Rotational Motions of Single Molecules by Polarized Total Internal Reflection Fluorescence Microscopy (polTIRFM)

    PubMed Central

    Beausang, John F.; Sun, Yujie; Quinlan, Margot E.; Forkey, Joseph N.; Goldman, Yale E.

    2013-01-01

    In this article, we describe methods to detect the spatial orientation and rotational dynamics of single molecules using polarized total internal reflection fluorescence microscopy (polTIRFM). polTIRFM determines the three-dimensional angular orientation and the extent of wobble of a fluorescent probe bound to the macromolecule of interest. We discuss single-molecule versus ensemble measurements, as well as single-molecule techniques for orientation and rotation, and fluorescent probes for orientation studies. Using calmodulin (CaM) as an example of a target protein, we describe a method for labeling CaM with bifunctional rhodamine (BR). We also describe the physical principles and experimental setup of polTIRFM. We conclude with a brief introduction to assays using polTIRFM to assess the interaction of actin and myosin. PMID:22550303

  10. CASSIOPE Enhanced Polar Outflow Probe (e-POP) Small Satellite Mission: Space Plasma Observations and International Collaborations

    NASA Astrophysics Data System (ADS)

    Yau, A. W.; James, H. G.

    2009-06-01

    In-situ observation of the micro-scale characteristics of plasma acceleration and related outflow processes is a primary scientific target of the Canadian Enhanced Polar Outflow Probe (e-POP) small satellite mission. The e-POP instrument payload will include imaging plasma and neutral particle sensors, magnetometers, dual-frequency GPS receivers, CCD cameras, a radio wave receiver and a beacon transmitter. The imaging plasma sensors will measure particle distributions and the magnetometers will measure field-aligned currents on the time scale of 10 ms and spatial scale of ~100 m. The CCD cameras will perform auroral imaging on the time scale of 100 ms and at spatial (pixel) resolution up to 0.4 km. The GPS and radio-wave receivers will perform near real-time imaging studies of the ionosphere in conjunction with ground-based radars, and the beacon transmitter in conjunction with ground receiving stations. The e-POP payload will be flown on the Canadian CASSIOPE small satellite, which is scheduled for launch in late 2008 into a polar orbit (325×1500 km, 80° inclination). International collaboration is an important and integral part of the e-POP mission strategy. Two of the 8 e-POP science instruments will be contributed by JAXA/ISAS, Japan, and Naval Research Laboratory, USA, respectively. Many of the planned e-POP investigations will entail coordinated observations using Canadian as well as foreign ground facilities, including magnetic and optical observatories, radars and heaters, such as the HAARP facility in Alaska, the EISCAT radar, and the NSF Antarctic facility. International collaboration in these investigations is expected to significantly enhance the science returns of the e-POP mission.

  11. Challenges Faced by African International Students at a Metropolitan Research University: A Phenomenological Case Study

    ERIC Educational Resources Information Center

    Evivie, Loretta Gbemudu

    2009-01-01

    The number of international students coming to the United States has increased from 48,486 in 1959-1960 to 623,805 in the 2007-2008 academic years (Open Doors, 2008). These students contributed $15.5 billion to the United States economy, making education the nation's fifth largest service export (Open Doors, 2008). The literature has focused on…

  12. Contemporary Trends in East Asian Higher Education: Dispositions of International Students in a Taiwan University

    ERIC Educational Resources Information Center

    Roberts, Amy; Chou, Prudence; Ching, Greg

    2010-01-01

    This article details a mixed methods study conducted during the 2007-2008 academic year at the National Chengchi University (NCCU) in Taipei Taiwan. It contributes to discourse examining the opportunities and challenges of international student enrollments in institutions of higher learning around the globe. In scope it details an empirical study…

  13. PREFACE: International Symposium on (e,2e), Double Photoionization and Related Topics & 15th International Symposium on Polarization and Correlation in Electronic and Atomic Collisions

    NASA Astrophysics Data System (ADS)

    Martin, Nicholas L. S.; deHarak, Bruno A.

    2010-01-01

    From 30 July to 1 August 2009, over a hundred scientists from 18 countries attended the International Symposium on (e,2e), Double Photoionization and Related Topics and the 15th International Symposium on Polarization and Correlation in Electronic and Atomic Collisions which were held at the W T Young Library of the University of Kentucky, USA. Both conferences were satellite meetings of the XXVI International Conference on Photonic, Electronic and Atomic Collisions (ICPEAC) held in Kalamazoo, Michigan, USA, 21-28 July 2009. These symposia covered a broad range of experimental and theoretical topics involving excitation, ionization (single and multiple), and molecular fragmentation, of a wide range of targets by photons and charged particles (polarized and unpolarized). Atomic targets ranged from hydrogen to the heavy elements and ions, while molecular targets ranged from H2 to large molecules of biological interest. On the experimental front, cold target recoil ion momentum spectroscopy (COLTRIMS), also known as the Reaction Microscope because of the complete information it gives about a wide variety of reactions, is becoming commonplace and has greatly expanded the ability of researchers to perform previously inaccessible coincidence experiments. Meanwhile, more conventional spectrometers are also advancing and have been used for increasingly sophisticated and exacting measurements. On the theoretical front great progress has been made in the description of target states, and in the scattering calculations used to describe both simple and complex reactions. The international nature of collaborations between theorists and experimentalists is exemplified by, for example, the paper by Ren et al which has a total of 13 authors of whom the experimental group of six is from Heidelberg, Germany, one theoretical group is from Australia, with the remainder of the theoreticians coming from several different institutions in the United States. A total of 52 invited talks and

  14. BC International-Student K-12 Enrolment and Tuition Fees in Decline: Update, 2009-10. BCTF Research Report. Section V. 2011-EF-01

    ERIC Educational Resources Information Center

    Kuehn, Larry; Field, Anne

    2011-01-01

    The years of ever-increasing revenue from international students appear to have come to an end. Data show that the number of international students and the revenue they generated rose annually throughout the first years of the past decade; however, enrolment and associated fee revenue for school districts reached its highest level in 2007-2008,…

  15. Bouncing Continents: Insights into the Physics of the Polar Regions of the Earth from the POLENET Project in the International Polar Year

    ERIC Educational Resources Information Center

    Reading, Anya M.

    2008-01-01

    When ice sheets melt, and reduce the load on the surface of the Earth, the land areas beneath them bounce back up. New, accurate observations are needed to investigate this uplift and its implications effectively. This article provides a topical starting point for investigating some applications of physics applied to the polar regions of the…

  16. Integrating Access to Arctic Environmental Change and Human Health Research for the International Polar Year and Beyond

    NASA Astrophysics Data System (ADS)

    Garrett, C. L.

    2006-12-01

    hosting the Arctic Human Health Initiative (AHHI), the human health focus of the International Polar Year activities. AHHI will coordinate research in the areas of infectious disease; the effects of anthropogenic pollution, UV radiation, and climate variability on human health; and telehealth innovations. A major goal of AHHI is the better integration of the findings of Arctic health research through outreach programs and public education.

  17. Penta prism laser polarizer.

    PubMed

    Lotem, H; Rabinovitch, K

    1993-04-20

    A novel type of laser prism polarizer is proposed. The polarizer is characterized by a high transmission efficiency, a high optical damage threshold, and a high extinction ratio. The polarizer is shaped like a regular penta prism and, thus, it is a constant deviation angle device. Polarization effects occur upon the two internal cascade reflections in the prism. Anisotropic and Isotropic types of the polarizer are discussed. The isotropic polarizer is a prism made of a high refractive-index glass coated by multilayer polarization-type dielectric coatings. Efficient s-state polarization is obtained because of p-state leakage upon the two internal cascade reflections. The anisotropic polarizer is made of a birefringent crystal in which angular polarization splitting is obtained by the bireflectance (double-reflection) effect. Fanning of a laser beam into up to eight polarized beams is possible in a prism made of a biaxial crystal. PMID:20820335

  18. Implementing SPRINTT [Student Polar Research with IPY National(and International)Teacher Training] in 5th Grade Science

    NASA Astrophysics Data System (ADS)

    Glass, D. S.

    2009-12-01

    I implemented the new NSF-funded SPRINTT (Student Polar Research with IPY National (and International) Teacher Training) curriculum with a 5th grade science class. SPRINTT, developed at U.S. Satellite Laboratory, Inc., is a 5-8 week science program teaching 5th through 10th graders to investigate climate change using polar data. The program includes perspectives of both Western scientists and the indigenous Northern population. The course contains three phases: Phase 1 includes content, data interpretation, and hands-on experiments to study Frozen Water, Frozen Land, and Food; Phase 2 (optional) includes further content on specific polar topics; and Phase 3 is a scaffolded research investigation. Before the course, teachers were trained via live webinars. This curriculum capitalizes on children’s innate fascination with our planet’s final frontier and combines it with the politically and scientifically relevant topic of climate change. In 2009, I used SPRINTT with 23 heterogeneous fifth grade students at National Presbyterian School in Washington DC for an environmental science unit. Overall, it was a success. The students met most of the learning objectives and showed enthusiasm for the material. I share my experiences to help other educators and curriculum developers. The Phase 1 course includes earth science (glaciers, sea ice, weather and climate, greenhouse gases, seasons, and human impacts on environments), life science (needs of living things, food and energy transfer, adaptations, and ecosystems and biomes) and physical science (phases of matter). Tailoring the program, I focused on Phase 1, the most accessible material and content, while deemphasizing the more cumbersome Phase 3 online research project. Pre-assessments documented the students’ misconceptions and informed instruction. The investigations were appropriately educational and interesting. For example, students enjoyed looking at environmental factors and their impact on the people in the

  19. The North Polar Layered Deposits on Mars: The Internal Layering of Gemina Lingula and Implications for Ice Flow

    NASA Astrophysics Data System (ADS)

    Karlsson, Nanna B.; Holt, John W.; Hindmarsh, Richard C. A.; Choudhary, Prateek

    2010-05-01

    The North Polar Layered Deposits (NPLD) is one of the largest reservoirs of surface water on Mars and, via an active exchange of water vapour with the atmosphere, it plays an important role in the Martian climate. The impact of ice flow on the overall shape of the NPLD is still widely debated. A study by Winebrenner et al. (2008) found evidence for relict flow lines in the southernmost part of the NPLD called Gemina Lingula (GL). Other studies have concluded that the upper part of the NPLD shows no evidence of flow (Fishbaugh and Hvidberg, 2006) and that surface mass balance alone can produce the topography (Greve et al., 2004 and Greve and Mahajan, 2005) . This paper presents results from an analysis of radar data from the SHARAD (SHallow RADar) instrument on board NASA's Mars Reconnaissance Orbiter. The SHARAD instrument operates with a 20MHz centre frequency and a 10MHz bandwidth and one of its primary mission goals is to map the state and distribution of water on Mars. For more details on the SHARAD instrument please refer to Seu et al. (2007). In the SHARAD data we identified and mapped six internal horizons from over 80 radar lines retrieved over GL. All horizons were easily identifiable in the majority of the data and were on average present in over 80% of the radar data considered. The observed layers were then compared to modelled layers from a 3D ice flow model. The model uses a smoothed surface topography, where troughs and scarps have been filled in, and assumes that the shape and the mass balance of the NPLD are constant in time. The shape of the internal layers are then calculated as they would appear in a flowing ice cap given those parameters. More information on the model can be found in Hindmarsh et al. (2009). The overall fit between modelled and observed layers is reasonably good, but the goodness of the fit varies both between the different horizons and the different regions of GL. Horizons in the upper part of the ice fit less well than

  20. Polar plumes' orientation and the Sun's global magnetic field

    NASA Astrophysics Data System (ADS)

    de Patoul, Judith; Inhester, Bernd; Cameron, Robert

    2013-10-01

    Aims: We characterize the orientation of polar plumes as a tracer of the large-scale coronal magnetic field configuration. We monitor in particular the north and south magnetic pole locations and the magnetic opening during 2007-2008 and provide some understanding of the variations in these quantities. Methods: The polar plume orientation is determined by applying the Hough-wavelet transform to a series of EUV images and extracting the key Hough space parameters of the resulting maps. The same procedure is applied to the polar cap field inclination derived from extrapolating magnetograms generated by a surface flux transport model. Results: We observe that the position where the magnetic field is radial (the Sun's magnetic poles) reflects the global organization of magnetic field on the solar surface, and we suggest that this opens the possibility of both detecting flux emergence anywhere on the solar surface (including the far side) and better constraining the reorganization of the corona after flux emergence.

  1. Total internal reflection without change of polarization using a right-angle prism with half-wavelength-thick optical interference coating.

    PubMed

    Azzam, R M A

    2009-02-01

    Monochromatic light, which is polarized in an arbitrary state, is totally internally reflected at angle of incidence phi=45 degrees without change of polarization by a right-angle prism of refractive index n0=1+1/Square root of 2=1.70711 (e.g., N-LAK8 Schott glass at wavelength lambda=706 nm), which is coated with a transparent thin film of refractive index n1=(1+1/2)1/2=1.30656 (e.g., vacuum-deposited fluoride material) and of metric thickness equal to half of the vacuum wavelength of incident light, d=lambda/2. The ambient medium of evanescent refraction is assumed to be vacuum, air, or an inert gas. Wavelength shifts of +/-50 nm, or changes of the internal angle of incidence of +/-1 degrees around 45 degrees, cause phase errors of only a few degrees. The reflected and incident polarization states are nearly identical in the presence of such small phase errors. PMID:19183662

  2. A Proposal submitted to Biological Systems Science Division of DOE requesting Participant Support Costs for the Fifth International Conference on Polar and Alpine Microbiology

    SciTech Connect

    Priscu, John

    2012-11-20

    The 5th International Conference on Polar and Alpine Microbiology (PAM5) was held in Big Sky, Montana (USA) from 8-12 September 2013. This meeting is a continuation of the highly successful meetings previously held in Rovaniemi, Finland (2004), Innsbruck, Austria (2006), Banff, Canada (2008) and Ljubljana, Slovenia (2011), which brought together leading international researchers and students in this field. The objectives of the Big Sky meeting were to bring together scientists, students and professionals to discuss all aspects of cold-adapted microorganisms and the roles they play in polar and alpine environments, to understand the role of these organisms in our search for life on other icy worlds, to address recent developments, and to exchange ideas and experiences on an international scale. The conference provided a multi-disciplinary forum to explore emerging areas in the field and as always, will have a wealth of opportunities for the exchange of ideas and building of collaborations. Funds were requested to help defray registration fees and travel costs of 13 early career scientists. Distribution of the funds were based on the quality of the abstracts submitted.

  3. PINTEX Data: Numeric results from the Polarized Internal Target Experiments (PINTEX) at the Indiana University Cyclotron Facility

    DOE Data Explorer

    Meyer, H. O.

    The PINTEX group studied proton-proton and proton-deuteron scattering and reactions between 100 and 500 MeV at the Indiana University Cyclotron Facility (IUCF). More than a dozen experiments made use of electron-cooled polarized proton or deuteron beams, orbiting in the 'Indiana Cooler' storage ring, and of a polarized atomic-beam target of hydrogen or deuterium in the path of the stored beam. The collaboration involved researchers from several midwestern universities, as well as a number of European institutions. The PINTEX program ended when the Indiana Cooler was shut down in August 2002. The website contains links to some of the numerical results, descriptions of experiments, and a complete list of publications resulting from PINTEX.

  4. Polarizing phase shifting interferometry of total internal reflection light for measurement of refractive index and its spatial variation in liquid samples

    NASA Astrophysics Data System (ADS)

    Das, Tania; Bhattacharya, Kallol

    2016-07-01

    It is well known that the phase change in total internal reflection (TIR) is a function of the refractive indices of the pair of media involved. The spatial phase variations in a totally internally reflected beam are accurately measured using a Mach Zehnder interferometer employing polarization phase shifting technique. The evaluated phase change is then related to the refractive index variations of the rarer medium. One of the salient features of the proposed technique is that, unlike most interferometric methods where the measured phase is a function of the sample thickness, TIR phase is independent of the sample thickness as long as the evanescent wave field is fully confined within the sample. The theory of the technique is discussed and experimental results showing the three-dimensional profiles of the measured refractive indices and its spatial variations are presented.

  5. The Association of Polar Early Career Scientists (APECS): A Model for the Professional Development of Scientists (Invited)

    NASA Astrophysics Data System (ADS)

    Baeseman, J. L.; Apecs Leadership Team

    2010-12-01

    Efforts like the International Polar Year 2007-2008 (IPY) have helped to increase research efforts as well as enhancing the integration of education and outreach into research projects and developing the next generation of researchers. One of the major legacies of the IPY was the creation of the Association of Polar Early Career Scientists (APECS), which was developed in 2006 by young researchers and focuses on helping each other develop the skills needed for successful careers in research by working with senior mentors. APECS is an international and interdisciplinary organization of over 2000 early career researchers and educators with interests in the Polar Regions and the wider cryosphere from 45 countries. APECS aims to stimulate interdisciplinary and international research collaborations, and develop effective future leaders in polar research, education and outreach. This is achieved by - Facilitating international and interdisciplinary networking opportunities to share ideas and experiences and to develop new research directions and collaborations, - Providing opportunities for professional career development for both academic and alternative research professions, and - Promoting education and outreach as an integral component of polar research and to stimulate future generations of polar researchers. Since its inception, APECS has strived to develop a strong network of partnerships with senior international organizations and scientific bodies to provide career development opportunities for young researchers. These partnerships have led to early-career representation on science planning bodies at an international level, the mandate of early career researchers serving as co-chairs at science conferences, the development of a mentorship program, field schools and techniques workshops, mentor panel discussions at conferences and increased funding for young researchers to attend conferences. APECS has also worked with an international teachers network to develop

  6. Historical and Near Real-Time Physical, Chemical, and Biological Oceanographic Data in Support of the International Polar Year 2007-08

    NASA Astrophysics Data System (ADS)

    Tatusko, R. L.; Allegra, A. J.; Beattie, J. A.; Dwivedi, P. H.; Grimes, D.; Hamilton, M. A.; Levitus, S.; Sun, C. L.; Woods, M. H.

    2004-12-01

    The U.S. NOAA/NESDIS/National Oceanographic Data Center (NODC), located in Silver Spring, Maryland, has extensive capabilities in archiving and providing public access to polar oceanographic and coastal data, products, and information. The World Ocean Database (WOD), a scientifically quality-controlled, global, oceanographic database, is the most comprehensive database of historical ocean profile data and plankton measurements in existence. The World Data Center for Oceanography (WDC) in Silver Spring conducts international exchange of oceanographic observations in accordance with the principles set forth by the International Council of Scientific Unions (ICSU). The WDC is collocated with and operated by the NODC, and it also leads the Intergovernmental Oceanographic Commission (IOC) Global Oceanographic Data Archaeology and Rescue (GODAR) project, which attempts to locate and rescue historical data that are at risk of being lost due to media decay or neglect, and the IOC World Ocean Database (WOD) project, which is intended to stimulate international exchange of modern oceanographic data. The WOD will continue to be enhanced as new data is received through the WDC, IOC projects, and data incorporated into the NODC Archive Management and Metadata System (AMS). The Ocean Archive System (OAS) is the public Web interface to the AMS, and it provides access to original sets of ocean data as they were provided to (and archived by) the NODC. The NODC also participates in the Global Temperature-Salinity Profile Program (GTSPP), which is a cooperative international program designed to develop and maintain a global ocean T-S resource with data that are as up-to-date and of the highest quality as possible. It also operates the long-term archive for Argo data, also known as the Global Argo Data Repository (GADR). The NOAA Central Library, also a division of NODC, maintains the largest meteorological collection in the western hemisphere and supports extensive oceanographic and

  7. OMAE 1996 -- Proceedings of the 15. international conference on offshore mechanics and arctic engineering. Volume 4: Arctic/polar technology

    SciTech Connect

    Nixon, W.A.; Sodhi, D.S.; Kennedy, K.P.; Bugno, W.

    1996-12-01

    Volume 4 contains papers on the following topics: arctic/polar technology and development; ice properties; ice engineering; applied ice mechanics; ice-structure interaction; arctic structures and operations; frozen soil properties; and Russian Arctic development. In addition to the regular topics covered in OMAE conferences, there has been a special workshop as part of this year`s conference. In keeping with issues of current interest, there is a workshop on development of oil resources in the Russian Arctic. Over two days, papers dealing with development of oil and gas resources in the Russian Arctic are presented. Volume 4 contains papers from this workshop. Some of the papers have been processed separately for inclusion on the data base.

  8. High Power Polarized Positron Source

    NASA Astrophysics Data System (ADS)

    Mikhailichenko, Alexander

    2009-09-01

    We discuss the basics of polarized positron production by low energy polarized electrons. Efficiency of conversion ˜0.1-1% might be interesting for the Continuous Electron Beam Accelerator Facility (CEBAF) and the International Linear Collider (ILC).

  9. Decadal Time Scale change in terrestrial plant communities in North American arctic and alpine tundra: A contribution to the International Polar Year Back to the Future Project (Invited)

    NASA Astrophysics Data System (ADS)

    Tweedie, C. E.; Ebert-May, D.; Hollister, R. D.; Johnson, D. R.; Lara, M. J.; Villarreal, S.; Spasojevic, M.; Webber, P.

    2010-12-01

    The International Polar Year-Back to the Future (IPY-BTF) is an endorsed International Polar Year project (IPY project #214). The overarching goal of this program is to determine how key structural and functional characteristics of high latitude/altitude terrestrial ecosystems have changed over the past 25 or more years and assess if such trajectories of change are likely to continue in the future. By rescuing data, revisiting, re-sampling historic research sites and assessing environmental change over time, we aim to provide greater understanding of how tundra is changing and what the possible drivers of these changes are. Resampling of sites established by Patrick J. Webber between 1964 and 1975 in northern Baffin Island, Northern Alaska and in the Rocky Mountains form a key contribution to the BTF project. Here we report on resampling efforts at each of these locations and initial results of a synthesis effort that finds similarities and differences in change between sites. Results suggest that although shifts in plant community composition are detectable at each location, the magnitude and direction of change differ among locations. Vegetation shifts along soil moisture gradients is apparent at most of the sites resampled. Interestingly, however, wet communities seem to have changed more than dry communities in the Arctic locations, while plant communities at the alpine site appear to be becoming more distinct regardless of soil moisture status. Ecosystem function studies performed in conjunction with plant community change suggest that there has been an increase in plant productivity at most sites resampled, especially in wet and mesic land cover types.

  10. Search for Antihelium with the BESS-Polar Spectrometer

    NASA Technical Reports Server (NTRS)

    Sasaki, M.; Mitchell, J. W.; Hams, T.; Abe, K.; Fuke, H.; Haino, S.; Hasegawa, M.; Horikoshi, A.; Itazaki, A.; Kim, K. C.; Kumazawa, T.; Kusumoto, A.; Lee, M. H.; Makida, Y.; Matsuda, S.; Matsukawa, Y.; Matsumoto, K.; Streitmatter, R. E.; Myers, Z.; Nishimura, J.; Nozaki, M.; Orito, R.; Ormes, J. F.; Sakai, K.; Seo, E. S.

    2012-01-01

    In two long-duration balloon flights over Antarctica, the BESS-Polar collaboration has searched for antihelium in the cosmic radiation with higher sensitivity than any reported investigation. BESSPolar I flew in 2004, observing for 8.5 days. BESS-Polar II flew in 2007-2008, observing for 24.5 days. No antihelium candidate was found in BESS-Polar I data among 8.4 x 10(exp 6) [Z] = 2 nuclei from 1.0 to 20 GV or in BESS-Polar II data among 4.0 x 10(exp 7) [Z] = 2 nuclei from 1.0 to 14 GV. Assuming antihelium to have the same spectral shape as helium, a 95% confidence upper limit of 6.9 x 10(exp -8) was determined by combining all the BESS data, including the two BESS-Polar flights. With no assumed antihelium spectrum and a weighted average of the lowest antihelium efficiencies from 1.6 to 14 GV, an upper limit of 1.0 x 10(exp -7) was determined for the combined BESS-Polar data. These are the most stringent limits obtained to date.

  11. Arctic Ocean circulation, processes and water masses: A description of observations and ideas with focus on the period prior to the International Polar Year 2007-2009

    NASA Astrophysics Data System (ADS)

    Rudels, Bert

    2015-03-01

    The evolving knowledge of the Arctic Ocean, its hydrography and its water masses and their transformations and circulation is reviewed starting with the observations made on Fram 1893-1896 and extending to the International Polar Year (IPY) 2007-2009. The expeditions and observations after Fram to the mid 20th century as well as the more extensive and systematic studies of water masses and circulation made from ice stations and airborne expeditions from the late 1940s to the late 1970s are briefly described. The early concepts of the connections and exchanges between the Arctic Ocean and the world ocean are also discussed. In the 1980s scientific icebreakers were beginning to enter the inner parts of the Arctic Ocean and large international programmes were launched, culminating in the IPY. The changes in the Arctic Ocean, first noted in the Atlantic layer in 1990 and shortly after in the upper layers, are described. The exchanges between the Arctic Ocean and the surrounding seas through the four main openings, Fram Strait, Barents Sea, Bering Strait and the Canadian Arctic Archipelago as well the volume and freshwater balances of the Arctic Ocean are examined.

  12. An Ultra-Wideband, Microwave Radar for Measuring Snow Thickness on Sea Ice and Mapping Near-Surface Internal Layers in Polar Firn

    NASA Technical Reports Server (NTRS)

    Panzer, Ben; Gomez-Garcia, Daniel; Leuschen, Carl; Paden, John; Rodriguez-Morales, Fernando; Patel, Azsa; Markus, Thorsten; Holt, Benjamin; Gogineni, Prasad

    2013-01-01

    Sea ice is generally covered with snow, which can vary in thickness from a few centimeters to >1 m. Snow cover acts as a thermal insulator modulating the heat exchange between the ocean and the atmosphere, and it impacts sea-ice growth rates and overall thickness, a key indicator of climate change in polar regions. Snow depth is required to estimate sea-ice thickness using freeboard measurements made with satellite altimeters. The snow cover also acts as a mechanical load that depresses ice freeboard (snow and ice above sea level). Freeboard depression can result in flooding of the snow/ice interface and the formation of a thick slush layer, particularly in the Antarctic sea-ice cover. The Center for Remote Sensing of Ice Sheets (CReSIS) has developed an ultra-wideband, microwave radar capable of operation on long-endurance aircraft to characterize the thickness of snow over sea ice. The low-power, 100mW signal is swept from 2 to 8GHz allowing the air/snow and snow/ ice interfaces to be mapped with 5 c range resolution in snow; this is an improvement over the original system that worked from 2 to 6.5 GHz. From 2009 to 2012, CReSIS successfully operated the radar on the NASA P-3B and DC-8 aircraft to collect data on snow-covered sea ice in the Arctic and Antarctic for NASA Operation IceBridge. The radar was found capable of snow depth retrievals ranging from 10cm to >1 m. We also demonstrated that this radar can be used to map near-surface internal layers in polar firn with fine range resolution. Here we describe the instrument design, characteristics and performance of the radar.

  13. Analysis of flow and LDL concentration polarization in siphon of internal carotid artery: Non-Newtonian effects.

    PubMed

    Sharifi, Alireza; Niazmand, Hamid

    2015-10-01

    Carotid siphon is known as one of the risky sites among the human intracranial arteries, which is prone to formation of atherosclerotic lesions. Indeed, scientists believe that accumulation of low density lipoprotein (LDL) inside the lumen is the major cause of atherosclerosis. To this aim, three types of internal carotid artery (ICA) siphon have been constructed to examine variations of hemodynamic parameters in different regions of the arteries. Providing real physiological conditions, blood considered as non-Newtonian fluid and real velocity and pressure waveforms have been employed as flow boundary conditions. Moreover, to have a better estimation of risky sites, the accumulation of LDL particles has been considered, which has been usually ignored in previous relevant studies. Governing equations have been discretized and solved via open source OpenFOAM software. A new solver has been built to meet essential parameters related to the flow and mass transfer phenomena. In contrast to the common belief regarding negligible effect of blood non-Newtonian behavior inside large arteries, current study suggests that the non-Newtonian blood behavior is notable, especially on the velocity field of the U-type model. In addition, it is concluded that neglecting non-Newtonian effects underestimates the LDL accumulation up to 3% in the U-type model at the inner side of both its bends. However, in the V and C type models, non-Newtonian effects become relatively small. Results also emphasize that the outer part of the second bend at the downstream is also at risk similar to the inner part of the carotid bends. Furthermore, from findings it can be implied that the risky sites strongly depend on the ICA shape since the extension of the risky sites are relatively larger for the V-type model, while the LDL concentrations are higher for the C-type model. PMID:26313530

  14. Potential Uses of EarthSLOT (an Earth Science, Logistics, and Outreach Terrainbase) for Education and Integration in the International Polar Year

    NASA Astrophysics Data System (ADS)

    Nolan, M.

    2004-12-01

    EarthSLOT is an internet-based, 3D, interactive terrain and data visualization system that may have many potential uses as an education and integration tool for International Polar Year projects. Recently funded by NSF's Office of Polar Programs for use in the Arctic, the global nature of the application lends itself well for use at both poles and everywhere in between. The application allows one to start with a spinning earth and zoom down to surface level. The highest resolution digital elevation models available provide the necessary 3D topographic perspective and a variety of possible high-resolution satellite and aerial imagery layers add surface realism; resolution can be down to the centimeter level for either type of data, and frequently acquired satellite imagery may be updated automatically as it arrives. Superimposed on this can be nearly any form of vector or annotation layers, such as shapefiles, polygons, point data, and 3D models (still and moving), which can be easily imported from existing GIS applications or spreadsheets. External databases can also be queried and the results served seamlessly. The entire application is served over the internet, and any connection with speeds over 300kps allows one to interactively fly with a minimum of performance lag. EarthSLOT stands for Earth Science, Logistics, and Outreach Terrainbase, targeting the user-groups of scientists, logisticians, and the public. Approved scientific users can add their own vector content to the application on their own, such that they can create their own custom applications featuring their data but using our underlying earth model with a minimum of interaction with us. For example, an oceanographer can add ship tracks or buoy locations to the model with links to data, host the link on his or her own web page, and invite collaborators to view the spatial relationship of their data to underlying bathymetry. Logisticians or program managers interested in understanding the spatial

  15. Multi-level approach for the integrated assessment of polar organic micropollutants in an international lake catchment: the example of Lake Constance.

    PubMed

    Moschet, Christoph; Götz, Christian; Longrée, Philipp; Hollender, Juliane; Singer, Heinz

    2013-07-01

    Polar organic micropollutants (MPs) can have ecotoxicological effects on aquatic ecosystems and their occurrence in drinking water is a threat to public health. An extensive exposure assessment of MPs in large river and lake catchments is a necessary but challenging proposition for researchers and regulators. To get a complete picture of MP exposure in a large catchment, we employed a novel integrated strategy including MP measurement in the international catchment of Lake Constance and mass-flux modeling. A comprehensive screening of 252 MPs in the lake water by high-resolution mass spectrometry was used to identify the most commonly present MPs for the study site. It was found that the wastewater borne MPs diclofenac, carbamazepine, sulfamethoxazole, acesulfame, sucralose, benzotriazole, and methylbenzotriazole accounted for the most frequent and prominent findings. The concentration pattern of these compounds in the catchment was calculated based on regionalized inputs from wastewater treatment plants (WWTPs) and substance specific elimination rates. In 52, 8, and 3 of the 112 investigated river locations the concentration exceeded the predicted no-effect levels for diclofenac, sulfamethoxazole and carbamazepine, respectively. By coupling the catchment and lake model the effect of future trends in usage as well as possible mitigation options were evaluated for the tributaries and the lake. The upgrade of the major WWTPs in the catchment with a postozonation step would lead to a load reduction between 32% and 52% for all substances except for sucralose (10%). PMID:23441970

  16. Influence of internal electric fields on band gaps in short period GaN/GaAlN and InGaN/GaN polar superlattices

    SciTech Connect

    Gorczyca, I. Skrobas, K.; Suski, T.; Christensen, N. E.; Svane, A.

    2015-08-21

    The electronic structures of short period mGaN/nGa{sub y}Al{sub 1−y}N and mIn{sub y}Ga{sub 1-y}N/nGaN superlattices grown along the wurtzite c axis have been calculated for different alloy compositions y and various small numbers m of well- and n of barrier-monolayers. The general trends in gap behavior can, to a large extent, be related to the strength of the internal electric field, E, in the GaN and InGaN quantum wells. In the GaN/GaAlN superlattices, E reaches 4 MV/cm, while in the InGaN/GaN superlattices, values as high as E ≈ 6.5 MV/cm are found. The strong electric fields are caused by spontaneous and piezoelectric polarizations, the latter contribution dominating in InGaN/GaN superlattices. The influence of different arrangements of In atoms (indium clustering) on the band gap values in InGaN/GaN superlattices is examined.

  17. Global Geospace Science/Polar Plasma Laboratory: POLAR

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Global Geospace Science (GGS) Project is discussed as part of the International Solar-Terrestrial Physics (ISTP) Science Initiative. The objectives of Polar Plasma Laboratory (POLAR), one of the two spacecraft to be used by the Project to fill critical gaps in the scientific understanding of solar and plasma physics, are outlined. POLAR Laboratory is described, along with POLAR instrumentation, support subsystems, and orbits. Launch vehicle and injection into orbit are also addressed.

  18. Single molecule investigations of DNA looping using the tethered particle method and translocation by acto-myosin using polarized total internal reflection fluorescence microscopy

    NASA Astrophysics Data System (ADS)

    Beausang, John F.

    Single molecule biophysics aims to understand biological processes by studying them at the single molecule level in real time. The proteins and nucleic acids under investigation typically exist in an aqueous environment within ˜ ten degrees of room temperature. These seemingly benign conditions are actually quite chaotic at the nanoscale, where single bio-molecules perform their function. As a result, sensitive experiments and statistical analyses are required to separate the weak single molecule signal from its background. Protein-DNA interactions were investigated by monitoring DNA looping events in tethered particle experiments. A new analysis technique, called the Diffusive hidden Markov method, was developed to extract kinetic rate constants from experimental data without any filtering of the raw data; a common step that improves the signal to noise ratio, but at the expense of lower time resolution. In the second system, translocation of the molecular motor myosin along its actin filament track was studied using polarized total internal reflection (polTIRF) microscopy, a technique that determines the orientation and wobble of a single fluorophore attached to the bio-molecule of interest. The range of resolvable angles was increased 4-fold to include a hemisphere of possible orientations. As a result, the handedness of actin filament twirling as it translocated along a myosin-coated surface was determined to be left-handed. The maximum time resolution of a polTIRF setup was increased 50-fold, in part by recording the arrival times and polarization state of single photons using a modified time-correlated single photon counting device. A new analysis, the Multiple Intensity Change Point algorithm, was developed to detect changes in molecular orientation and wobble using the raw time-stamped data with no user-defined bins or thresholds. The analysis objectively identified changes in the orientation of a bifunctional-rhodamine labeled calmodulin that was attached

  19. Polar ozone

    NASA Technical Reports Server (NTRS)

    Solomon, S.; Grose, W. L.; Jones, R. L.; Mccormick, M. P.; Molina, Mario J.; Oneill, A.; Poole, L. R.; Shine, K. P.; Plumb, R. A.; Pope, V.

    1990-01-01

    The observation and interpretation of a large, unexpected ozone depletion over Antarctica has changed the international scientific view of stratospheric chemistry. The observations which show the veracity, seasonal nature, and vertical structure of the Antarctic ozone hole are presented. Evidence for Arctic and midlatitude ozone loss is also discussed. The chemical theory for Antarctic ozone depletion centers around the occurrence of polar stratospheric clouds (PSCs) in Antarctic winter and spring; the climatology and radiative properties of these clouds are presented. Lab studies of the physical properties of PSCs and the chemical processes that subsequently influence ozone depletion are discussed. Observations and interpretation of the chemical composition of the Antarctic stratosphere are described. It is shown that the observed, greatly enhanced abundances of chlorine monoxide in the lower stratosphere are sufficient to explain much if not all of the ozone decrease. The dynamic meteorology of both polar regions is given, interannual and interhemispheric variations in dynamical processes are outlined, and their likely roles in ozone loss are discussed.

  20. Annual Performance Report: 2007-2008 State Assessment Data

    ERIC Educational Resources Information Center

    Altman, Jason; Thurlow, Martha; Vang, Mai

    2010-01-01

    States and other educational entities receiving Part B funding under the Individuals with Disabilities Education Act (IDEA) submitted their Annual Performance Reports (APRs) and Section 618 Table 6 data together to the U.S. Secretary of Education on or before February 1, 2009. These reports may have been modified during the following few months,…

  1. Influenza update 2007-2008: vaccine advances, pandemic preparation.

    PubMed

    Mossad, Sherif B

    2007-12-01

    Influenza vaccination remains our best measure to prevent epidemic and pandemic influenza. We must continue to improve vaccination rates for targeted populations. Antiviral options are currently limited to the neuraminidase inhibitors. PMID:18183839

  2. Restrictions on Research Awards: Troublesome Clauses 2007/2008

    ERIC Educational Resources Information Center

    Association of American Universities, 2008

    2008-01-01

    This joint report by the Association of American Universities (AAU) and the Council on Governmental Relations (COGR) is based on a survey of 20 U.S. research universities that conduct significant amounts of federal research. It follows up on a 2003/2004 survey of the same institutions. The new report shows that, despite the concerns and…

  3. Report on 2007-2008 High Tunnel Studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    New management strategies are needed to produce strawberry planting materials that will fruit in off-season in the mid-Atlantic coast region. Also, a better understanding of mechanisms that control flowering in strawberries is needed to improve fall flowering in short-day type cultivars. When plug...

  4. Overview of global space activities in 2007/2008

    NASA Astrophysics Data System (ADS)

    Peter, Nicolas; Delmotte, Raphaëlle

    2009-08-01

    The period ranging from July 2007 to June 2008 has been marked by significant trends and issues in the space sector, particularly under the impulsion of space-faring countries. The internationalisation and globalisation of the space sector which started a few years ago have been gaining momentum as well. As a consequence, the size of the space sector has been growing, as well as the global competition for market shares.

  5. Terrestrial Planet Finder Interferometer: 2007-2008 Progress and Plans

    NASA Technical Reports Server (NTRS)

    Lawson, P. R.; Lay, O. P.; Martin, S. R.; Peters, R. D.; Gappinger, R. O.; Ksendzov, A.; Scharf, D. P.; Booth, A. J.; Beichman, C. A.; Serabyn, E.; Johnston, K. J.; Danchi, W. C.

    2008-01-01

    This paper provides an overview of technology development for the Terrestrial Planet Finder Interferometer (TPF-I). TPF-I is a mid-infrared space interferometer being designed with the capability of detecting Earth-like planets in the habitable zones around nearby stars. The overall technology roadmap is presented and progress with each of the testbeds is summarized. The current interferometer architecture, design trades, and the viability of possible reduced-scope mission concepts are also presented.

  6. Shillapoo Wildlife Area, Annual Report 2007-2008.

    SciTech Connect

    Calkins, Brian

    2007-10-01

    This report summarizes accomplishments, challenges and successes on WDFW's Shillapoo Wildlife Area funded under Bonneville Power Administration's (BPA) Wildlife Mitigation Program (BPA project No.2003-012-00) during the Fiscal Year 08 contract period October 1, 2007-September 30, 2008. The information presented here is intended to supplement that contained in BPA's PISCES contract development and reporting system. The organization below is by broad categories of work but references are made to individual work elements in the PISCES Statement of Work as appropriate. Significant progress was realized in almost all major work types. Of particular note was progress made in tree plantings and pasture rehabilitation efforts. This year's tree planting effort included five sites detailed below and in terms of the number of plants was certainly the largest effort on the wildlife area to date in one season. The planting itself took a significant amount of time, which was anticipated. However, installation of mats and tubes took much longer than expected which impacted planned fence projects in particular. Survival of the plantings appears to be good. Improvement to the quality of waterfowl pasture habitats is evident on a number of sites due to replanting and weed control efforts. Continuing long-term weed control efforts will be key in improving this particular type of habitat. A prolonged cold, wet spring and a number of equipment breakdowns presented stumbling blocks that impacted schedules and ultimately progress on planned activities. The unusual spring weather delayed fieldwork on pasture planting projects as well as weed control and slowed the process of maintaining trees and shrubs. This time lag also caused the continued deferral of some of our fencing projects. The large brush hog mower had the driveline break twice and the smaller tractor had an engine failure that caused it to be down for over a month. We have modified our budget plan for next year to include a temporary employee that will work primarily on tree maintenance and fencing projects to make sure that we make progress in these areas and we will be investigating whether a heavier duty driveline can be obtained for the mower.

  7. MCPS Special Education at a Glance 2007-2008

    ERIC Educational Resources Information Center

    Montgomery County Public Schools, 2008

    2008-01-01

    Montgomery County Public Schools (MCPS) "Special Education at a Glance," which includes a copy of the "Guide to Planning and Assessing School-Based Special Education Programs," provides in a single document, information about the special education population at each MCPS school, including enrollment, staffing, special education…

  8. Scotch Creek Wildlife Area 2007-2008 Annual Report.

    SciTech Connect

    Olson, Jim

    2008-11-03

    The Scotch Creek Wildlife Area is a complex of 6 separate management units located in Okanogan County in North-central Washington State. The project is located within the Columbia Cascade Province (Okanogan sub-basin) and partially addresses adverse impacts caused by the construction of Chief Joseph and Grand Coulee hydroelectric dams. With the acquisition of the Eder unit in 2007, the total size of the wildlife area is now 19,860 acres. The Scotch Creek Wildlife Area was approved as a wildlife mitigation project in 1996 and habitat enhancement efforts to meet mitigation objectives have been underway since the spring of 1997 on Scotch Creek. Continuing efforts to monitor the threatened Sharp-tailed grouse population on the Scotch Creek unit are encouraging. The past two spring seasons were unseasonably cold and wet, a dangerous time for the young of the year. This past spring, Scotch Creek had a cold snap with snow on June 10th, a critical period for young chicks just hatched. Still, adult numbers on the leks have remained stable the past two years. Maintenance of BPA funded enhancements is necessary to protect and enhance shrub-steppe and to recover and sustain populations of Sharp-tailed grouse and other obligate species.

  9. Rehabilitate Newsome Creek Watershed, 2007-2008 Annual Report.

    SciTech Connect

    Bransford, Stephanie

    2009-05-01

    The Nez Perce Tribe Department of Fisheries Resource Management, Watershed Division approaches watershed restoration with a ridge-top to ridgetop approach. The Nez Perce Tribe (NPT) and the Nez Perce National Forest (NPNF) have formed a partnership in completing watershed restoration activities, and through this partnership more work is accomplished by sharing funding and resources in our effort. The Nez Perce Tribe began watershed restoration projects within the Newsome Creek watershed of the South Fork Clearwater River in 1997. Progress has been made in restoring the watershed through road decommissioning and culvert replacement. Starting in FY 2001 and continuing into the present, a major stream restoration effort on the mainstem of Newsome Creek has been pursued. From completing a watershed assessment to a feasibility study of 4 miles of mainstem rehabilitation to carrying that forward into NEPA and a final design, we will begin the effort of restoring the mainstem channel of Newsome Creek to provide spawning and rearing habitat for anadromous and resident fish species. Roads have been surveyed and prioritized for removal or improvement as well as culverts being prioritized for replacement to accommodate fish passage throughout the watershed.

  10. Developments in mycotoxin analysis: an update for 2007-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review highlights developments in mycotoxin analysis and sampling over a period between mid-2007 and mid-2008. It covers the major mycotoxins aflatoxins, alternaria toxins, cyclopiazonic acid, fumonisins, ochratoxin, patulin, trichothecenes, and zearalenone. Some aspects of natural occurrence, ...

  11. Gilliam County Riparian Buffers 2007-2008 Annual Report.

    SciTech Connect

    2008-11-04

    During the contract year beginning July 1, 2007 and ending June 30, 2008, the CREP technician contacted 15 new landowners regarding an interest in either the CREP or the Continuous CRP programs. Most landowners requested a second meeting and most sites were visited to discuss possibilities of enrolling in a USDA riparian program. This year, a considerable amount of time was spent providing technical assistance to prior contracts as the practices are implemented. More time is being spent in planning site preparation so that NRCS and FSAs increasing concerns over plant survival are satisfied. A continued concern that the rate paid to the landowner for maintenance is not enough. Controlling competing vegetation is a major factor in increasing plant survival. Increasing costs in the methods used to control unwanted plants has made it difficult for contract holders to perform these methods as effectively as they would like. The projects that have continued maintenance are considerably more successful.

  12. Intervention for College Attendance Program: 2007-2008 Report

    ERIC Educational Resources Information Center

    Walters, Nancy

    2009-01-01

    The purpose of this report is to provide information on the outcomes of the Intervention for College Attendance Program, a program of competitive grants awarded to postsecondary institutions, professional organizations, and community-based organizations. Prior to the 2008-09 biennium, the program focused on provision of college awareness and the…

  13. Tennessee Higher Education Fact Book, 2007-2008

    ERIC Educational Resources Information Center

    Tennessee Higher Education Commission, 2008

    2008-01-01

    The Division of Policy, Planning, and Research has assembled the Tennessee Higher Education Fact Book which is a compilation of statistical information pertaining to higher education in Tennessee. This Fact Book contains tables and charts with data relevant to enrollment and transfers, persistence and attainment, and fiscal information about…

  14. Getting around Antarctica: New High-Resolution Mappings of the Grounded and Freely-Floating Boundaries of the Antarctic Ice Sheet Created for the International Polar Year

    NASA Technical Reports Server (NTRS)

    Bindschadler, R.; Choi, H.; Wichlacz, A.; Bingham, R.; Bohlander, J.; Brunt, K.; Corr, H.; Drews, R.; Fricker, H.; Hall, M.; Hindmarsh, R.; Kohler, J.; Padman, L.; Rack, W.; Rotschkly, G.; Urbini, S.; Vornberger, P.; Young, N.

    2011-01-01

    Two ice-dynamic transitions of the Antarctic ice sheet - the boundary of grounded ice features and the freely-floating boundary - are mapped at 15-m resolution by participants of the International Polar Year project ASAID using customized software combining Landsat-7 imagery and ICESat/GLAS laser altimetry. The grounded ice boundary is 53 610 km long; 74% abuts to floating ice shelves or outlet glaciers, 19% is adjacent to open or sea-ice covered ocean, and 7% of the boundary ice terminates on land. The freely-floating boundary, called here the hydrostatic line, is the most landward position on ice shelves that expresses the full amplitude of oscillating ocean tides. It extends 27 521 km and is discontinuous. Positional (one-sigma) accuracies of the grounded ice boundary vary an order of magnitude ranging from +/- 52m for the land and open-ocean terminating segments to +/- 502m for the outlet glaciers. The hydrostatic line is less well positioned with errors over 2 km. Elevations along each line are selected from 6 candidate digital elevation models based on their agreement with ICESat elevation values and surface shape inferred from the Landsat imagery. Elevations along the hydrostatic line are converted to ice thicknesses by applying a firn-correction factor and a flotation criterion. BEDMAP-compiled data and other airborne data are compared to the ASAID elevations and ice thicknesses to arrive at quantitative (one-sigma) uncertainties of surface elevations of +/-3.6, +/-9.6, +/-11.4, +/-30 and +/-100m for five ASAID-assigned confidence levels. Over one-half of the surface elevations along the grounded ice boundary and over one-third of the hydrostatic line elevations are ranked in the highest two confidence categories. A comparison between ASAID-calculated ice shelf thicknesses and BEDMAP-compiled data indicate a thin-ice bias of 41.2+/-71.3m for the ASAID ice thicknesses. The relationship between the seaward offset of the hydrostatic line from the grounded ice

  15. Enhanced polarization by the coherent heterophase interface between polar and non-polar phases

    NASA Astrophysics Data System (ADS)

    Kim, Gi-Yeop; Sung, Kil-Dong; Rhyim, Youngmok; Yoon, Seog-Young; Kim, Min-Soo; Jeong, Soon-Jong; Kim, Kwang-Ho; Ryu, Jungho; Kim, Sung-Dae; Choi, Si-Young

    2016-03-01

    A piezoelectric composite containing the ferroelectric polar (Bi(Na0.8K0.2)0.5TiO3: f-BNKT) and the non-polar (0.94Bi(Na0.75K0.25)0.5TiO3-0.06BiAlO3: BNKT-BA) phases exhibits synergetic properties which combine the beneficial aspects of each phase, i.e., the high saturated polarization (Ps) of the polar phase and the low coercive field (Ec) of the non-polar phase. To understand the origin of such a fruitful outcome from this type of polar/non-polar heterophase structure, comprehensive studies are conducted, including transmission electron microscopy (TEM) and finite element method (FEM) analyses. The TEM results show that the polar/non-polar composite has a core/shell structure in which the polar phase (core) is surrounded by a non-polar phase (shell). In situ electrical biasing TEM experiments visualize that the ferroelectric domains in the polar core are aligned even under an electric field of ~1 kV mm-1, which is much lower than its intrinsic coercive field (~3 kV mm-1). From the FEM analyses, we can find that the enhanced polarization of the polar phase is promoted by an additional internal field at the phase boundary which originates from the preferential polarization of the relaxor-like non-polar phase. From the present study, we conclude that the coherent interface between polar and non-polar phases is a key factor for understanding the enhanced piezoelectric properties of the composite.A piezoelectric composite containing the ferroelectric polar (Bi(Na0.8K0.2)0.5TiO3: f-BNKT) and the non-polar (0.94Bi(Na0.75K0.25)0.5TiO3-0.06BiAlO3: BNKT-BA) phases exhibits synergetic properties which combine the beneficial aspects of each phase, i.e., the high saturated polarization (Ps) of the polar phase and the low coercive field (Ec) of the non-polar phase. To understand the origin of such a fruitful outcome from this type of polar/non-polar heterophase structure, comprehensive studies are conducted, including transmission electron microscopy (TEM) and finite element

  16. Tissue polarity: PCP inheritance ensured by selective mitotic endocytosis.

    PubMed

    Founounou, Nabila; Le Borgne, Roland

    2011-09-27

    Recent findings report the selective internalization of core planar cell polarity components during mitosis followed by cell-non-autonomous polarized recycling. This novel mechanistic model explains how tissue polarity is inherited in daughter cells of proliferative tissue. PMID:21959155

  17. Enhanced polarization by the coherent heterophase interface between polar and non-polar phases.

    PubMed

    Kim, Gi-Yeop; Sung, Kil-Dong; Rhyim, Youngmok; Yoon, Seog-Young; Kim, Min-Soo; Jeong, Soon-Jong; Kim, Kwang-Ho; Ryu, Jungho; Kim, Sung-Dae; Choi, Si-Young

    2016-04-14

    A piezoelectric composite containing the ferroelectric polar (Bi(Na0.8K0.2)0.5TiO3: f-BNKT) and the non-polar (0.94Bi(Na0.75K0.25)0.5TiO3-0.06BiAlO3: BNKT-BA) phases exhibits synergetic properties which combine the beneficial aspects of each phase, i.e., the high saturated polarization (Ps) of the polar phase and the low coercive field (Ec) of the non-polar phase. To understand the origin of such a fruitful outcome from this type of polar/non-polar heterophase structure, comprehensive studies are conducted, including transmission electron microscopy (TEM) and finite element method (FEM) analyses. The TEM results show that the polar/non-polar composite has a core/shell structure in which the polar phase (core) is surrounded by a non-polar phase (shell). In situ electrical biasing TEM experiments visualize that the ferroelectric domains in the polar core are aligned even under an electric field of ∼1 kV mm(-1), which is much lower than its intrinsic coercive field (∼3 kV mm(-1)). From the FEM analyses, we can find that the enhanced polarization of the polar phase is promoted by an additional internal field at the phase boundary which originates from the preferential polarization of the relaxor-like non-polar phase. From the present study, we conclude that the coherent interface between polar and non-polar phases is a key factor for understanding the enhanced piezoelectric properties of the composite. PMID:26601654

  18. PSP toxin levels and plankton community composition and abundance in size-fractionated vertical profiles during spring/summer blooms of the toxic dinoflagellate Alexandrium fundyense in the Gulf of Maine and on Georges Bank, 2007, 2008, and 2010: 1. Toxin levels

    PubMed Central

    Deeds, Jonathan R.; Petitpas, Christian M.; Shue, Vangie; White, Kevin D.; Keafer, Bruce A.; McGillicuddy, Dennis J.; Milligan, Peter J.; Anderson, Donald M.; Turner, Jefferson T.

    2014-01-01

    As part of the NOAA ECOHAB funded Gulf of Maine Toxicity (GOMTOX)1 project, we determined Alexandrium fundyense abundance, paralytic shellfish poisoning (PSP) toxin composition, and concentration in quantitatively-sampled size-fractionated (20–64, 64–100, 100–200, 200–500, and > 500 μm) particulate water samples, and the community composition of potential grazers of A. fundyense in these size fractions, at multiple depths (typically 1, 10, 20 m, and near-bottom) during 10 large-scale sampling cruises during the A. fundyense bloom season (May–August) in the coastal Gulf of Maine and on Georges Bank in 2007, 2008, and 2010. Our findings were as follows: (1) when all sampling stations and all depths were summed by year, the majority (94% ± 4%) of total PSP toxicity was contained in the 20–64 μm size fraction; (2) when further analyzed by depth, the 20–64 μm size fraction was the primary source of toxin for 97% of the stations and depths samples over three years; (3) overall PSP toxin profiles were fairly consistent during the three seasons of sampling with gonyautoxins (1, 2, 3, and 4) dominating (90.7% ± 5.5%), followed by the carbamate toxins saxitoxin (STX) and neosaxitoxin (NEO) (7.7% ± 4.5%), followed by n-sulfocarbamoyl toxins (C1 and 2, GTX5) (1.3% ± 0.6%), followed by all decarbamoyl toxins (dcSTX, dcNEO, dcGTX2&3) (< 1%), although differences were noted between PSP toxin compositions for nearshore coastal Gulf of Maine sampling stations compared to offshore Georges Bank sampling stations for 2 out of 3 years; (4) surface cell counts of A. fundyense were a fairly reliable predictor of the presence of toxins throughout the water column; and (5) nearshore surface cell counts of A. fundyense in the coastal Gulf of Maine were not a reliable predictor of A. fundyense populations offshore on Georges Bank for 2 out of the 3 years sampled. PMID:25076816

  19. Polarization spectroscopy of tokamak plasmas

    SciTech Connect

    Wroblewski, D.

    1991-09-01

    Measurements of polarization of spectral lines emitted by tokamak plasmas provide information about the plasma internal magnetic field and the current density profile. The methods of polarization spectroscopy, as applied to the tokamak diagnostic, are reviewed with emphasis on the polarimetry of motional Stark effect in hydrogenic neutral beam emissions. 25 refs., 7 figs.

  20. Polarization developments

    SciTech Connect

    Prescott, C.Y.

    1993-07-01

    Recent developments in laser-driven photoemission sources of polarized electrons have made prospects for highly polarized electron beams in a future linear collider very promising. This talk discusses the experiences with the SLC polarized electron source, the recent progress with research into gallium arsenide and strained gallium arsenide as a photocathode material, and the suitability of these cathode materials for a future linear collider based on the parameters of the several linear collider designs that exist.

  1. Neuronal polarization.

    PubMed

    Takano, Tetsuya; Xu, Chundi; Funahashi, Yasuhiro; Namba, Takashi; Kaibuchi, Kozo

    2015-06-15

    Neurons are highly polarized cells with structurally and functionally distinct processes called axons and dendrites. This polarization underlies the directional flow of information in the central nervous system, so the establishment and maintenance of neuronal polarization is crucial for correct development and function. Great progress in our understanding of how neurons establish their polarity has been made through the use of cultured hippocampal neurons, while recent technological advances have enabled in vivo analysis of axon specification and elongation. This short review and accompanying poster highlight recent advances in this fascinating field, with an emphasis on the signaling mechanisms underlying axon and dendrite specification in vitro and in vivo. PMID:26081570

  2. Polarization Aberrations

    NASA Technical Reports Server (NTRS)

    Mcguire, James P., Jr.; Chipman, Russell A.

    1990-01-01

    The analysis of the polarization characteristics displayed by optical systems can be divided into two categories: geometrical and physical. Geometrical analysis calculates the change in polarization of a wavefront between pupils in an optical instrument. Physical analysis propagates the polarized fields wherever the geometrical analysis is not valid, i.e., near the edges of stops, near images, in anisotropic media, etc. Polarization aberration theory provides a starting point for geometrical design and facilitates subsequent optimization. The polarization aberrations described arise from differences in the transmitted (or reflected) amplitudes and phases at interfaces. The polarization aberration matrix (PAM) is calculated for isotropic rotationally symmetric systems through fourth order and includes the interface phase, amplitude, linear diattenuation, and linear retardance aberrations. The exponential form of Jones matrices used are discussed. The PAM in Jones matrix is introduced. The exact calculation of polarization aberrations through polarization ray tracing is described. The report is divided into three sections: I. Rotationally Symmetric Optical Systems; II. Tilted and Decentered Optical Systems; and Polarization Analysis of LIDARs.

  3. The BESS-Polar Proton & Helium flux measurements

    NASA Astrophysics Data System (ADS)

    Hams, T.; Yamamoto, A.; Mitchell, J.W.; Abe, K.; Fuke, H.; Haino, S.; Hasegawa, M.; Horikoshi, A.; Itazaki, A.; Kim, K.C.; Kumazawal, T.; Lee, M.H.; Makida, Y.; Matsuda, S.; Matsukawa, Y.; Matsumoto, K.; Moiseev, A.A.; Meyers, Z.; Nishimura, J.; Nozaki, M.; Orito, R.; Ormes, J.F.; Sakai, K.; Sasaki, M.; Seo, E.S.; Shikaze, Y.; Shinoda, R.; Streitmatter, R.E.; Suzuki, J.; Takasugi, Y.; Takeuchi, K.; Tanaka, K.; Thakur, N.; Yamagami, T.; Yoshida, T.; Yoshimura, K.

    The Balloon-borne Experiment with a Superconducting Spectrometer (BESS) instrument pro-vides precise measurements of the elemental and isotopic composition of the light Galactic cosmic radiation (GCR) component. The ability to determine the charge sign of incident par-ticles enables the instrument to search for GCR antimatter, which is a major objective of the BESS program. Since 1993, the US-Japan BESS collaboration has conducted 11 successful balloon flights, nine northern-latitude flights of 1-day duration and most recently two long-duration balloon flights (8.5 days in 2004 & 24.5 days in 2007/2008), with the BESS-Polar instrument. The BESS-Polar instrument is the current effort of BESS program specifically designed for long-duration, low-geomagnetic cutoff Antarctic flights with significantly increased transparency for incident CR particle allowing to study anti/proton down to 100 MeV and a faster data acquisition enables processing of all CR events without event selection. The first BESS-Polar flight was launched on Dec 13, 2004 from Williams Field, near McMurdo Station in Antarctica. The instrument recorded data for 8.5 days, limited by the cryogenic life time of the superconducting magnet. During this flight the BESS-Polar instrument recorded 0.9 x 109 CR events. In this paper, we present the absolute proton and helium flux for the first BESS-Polar flight as well as the time variation of the fluxes due to solar activity.

  4. Polar Bear

    USGS Publications Warehouse

    Amstrup, S.D.; DeMaster

    1988-01-01

    Polar bears are long-lived, late-maturing carnivores that have relatively low rates of reproduction and natural mortality. Their populations are susceptible to disturbance from human activities, such as the exploration and development of mineral resources or hunting. Polar bear populations have been an important renewable resource available to coastal communities throughout the Arctic for thousands of years.

  5. Polarized rainbow.

    PubMed

    Können, G P; de Boer, J H

    1979-06-15

    The Airy theory of the rainbow is extended to polarized light. For both polarization directions a simple analytic expression is obtained for the intensity distribution as a function of the scattering angle in terms of the Airy function and its derivative. This approach is valid at least down to droplet diameters of 0.3 mm in visible light. The degree of polarization of the rainbow is less than expected from geometrical optics; it increases with droplet size. For a droplet diameter >1 mm the locations of the supernumerary rainbows are equal for both polarization directions, but for a diameter <1 mm the supernumerary rainbows of the weaker polarization component are located between those in the strong component. PMID:20212586

  6. The Bess-Polar II Long Duration Flight Above Antarctica

    NASA Technical Reports Server (NTRS)

    Sasaki, Makoto; Yamamoto, Akira; Yoshimura, Koji; Makida, Yasuhiro; Matsuda, Shinya; Hasegawa, Masaya; Horikoshi, Atsushi; Tanaka, Ken-ichi; Suzuki, Junichi; Nishimura, Jun; Sakai, Ken-ichi; Shinoda, Ryoko; Orito, Reio; Matsukawa, Yosuke; Kusumoto, Akira; Yoshida, Tetsuya; Fuke, Hideyuki; Mitchell, John W.; Streitmatter, Robert E.; Hams, Thomas; Sasaki, Makoto; Seo, Eun-suk; Lee, Moo-hyon; Kim, Ki-chun; Thakur, Needharika

    2008-01-01

    The Balloon-borne Experiment with a Superconducting Spectrometer, BESS, has been developed to study elementary particle phenomena in the early universe through measurements of low energy antiprotons to investigate their origin and through a search for antihelium. The BESS collaboration carried out nine northern latitude flights between 1993 and 2002. BESS-Polar is an advanced program of the BESS collaboration to study these topics with much greater precision using long duration flights above Antarctica. The BESS-Polar spectrometer was successfully developed to accumulate much larger numbers of events during long duration flights around the South Pole. Approximately a factor of four reductions in the amount of material in the particle beam enables measurement of much lower energy antiprotons down to 100 MeV (at top of atmosphere). The first BESS-Polar flight (BESS-Polar I) of 8.5 days was carried out above Antarctica in December 2004. recording 900 million cosmic-ray events. The second BESS-Polar flight (BESS-Polar 11) was successfully carried out in the austral summer season of 2007-2008. Based on experience with BESS-Polar I, the spectrometer was improved in performance and achieved long term stability during the flight. A newly constructed magnet with a larger liquid He capacity and improved thermal insulation and an upgraded data storage system with larger capacity of hard disk drives (HDDs) enabled longer observation time. BESS-Polar II was launched on December 22, 2007 from Williams Field, McMurdo Station, in Antarctica. The spectrometer worked properly and observed cosmic rays for about 24.5 days at float altitude, recording 4.6 billion events on the HDDs until the limit of the magnet operation was reached on January 16, 2008. The flight was terminated and the spectrometer was safely landed on the West Antarctic ice sheet (1000 km from the South Pole) on January 21, 2008. Here, the BESS-Polar instrument is discussed, highlighting improvements made for BESS-Polar

  7. Polar Glaciology

    NASA Technical Reports Server (NTRS)

    Robin, G. D.

    1984-01-01

    Two fields of research on polar ice sheets are likely to be of dominant interest during the 1990s. These are: the role of polar ice sheets in the hydrological cycle ocean-atmosphere-ice sheets-oceans, especially in relation to climate change; and the study and interpretation of material in deep ice cores to provide improved knowledge of past climates and of the varying levels of atmospheric constituents such as CO2, NOx, SO2, aerosols, etc., over the past 200,000 years. Both topics require a better knowledge of ice dynamics. Many of the studies that should be undertaken in polar regions by Earth Observing System require similar instruments and techniques to those used elsewhere over oceans and inland surfaces. However to study polar regions two special requirements need to be met: Earth Observing System satellite(s) need to be in a sufficiently high inclination orbit to cover most of the polar regions. Instruments must also be adapted, often by relatively limited changes, to give satisfactory data over polar ice. The observational requirements for polar ice sheets in the 1990s are summarized.

  8. EDITORIAL: Polarization Optics

    NASA Astrophysics Data System (ADS)

    Turunen, Jari; Friesem, Asher A.; Friberg, Ari T.

    2004-03-01

    This special issue on Polarization Optics contains one review article and 23 research papers, many of which are based on presentations at the International Commission for Optics Topical Meeting on Polarization Optics, held in Polvijärvi, Finland, between 30 June and 3 July 2003. While this issue should not in any sense be considered as a `proceedings' of this meeting, the possibility of submitting papers to it was widely advertised during the meeting, which was attended by a large fraction of prominent scientists in the field of polarization optics. Thus the quality of papers in this special issue is high. In announcing both the meeting and this special issue, we emphasized that the concept of `polarization optics' should be understood in a wide sense. In fact, all contributions dealing with the vectorial nature of light were welcome. As a result, the papers included here cover a wide range of different aspects of linear and nonlinear polarization optics. Both theoretical and experimental features are discussed. We are pleased to see that the conference and this special issue both reflect the wide diversity of important and novel polarization phenomena in optics. The papers in this special issue, and other recently published works, demonstrate that even though polarization is a fundamental property of electromagnetic fields, interest in it is rapidly increasing. The fundamental relations between partial coherence and partial polarization are currently under vigorous research in electromagnetic coherence theory. In diffractive optics it has been found that the exploitation of the vectorial nature of light can be of great benefit. Fabrication of sophisticated, spatially variable polarization-control elements is becoming possible with the aid of nanolithography. Polarization singularities and the interplay of bulk properties and topology in nanoscale systems have created much enthusiasm. In nonlinear optics, the second harmonic waves generated on reflection and

  9. Spring polar ozone behavior

    NASA Technical Reports Server (NTRS)

    Aikin, Arthur C.

    1992-01-01

    Understanding of the springtime behavior of polar stratospheric ozone as of mid 1990 is summarized. Heterogeneous reactions on polar stratospheric clouds as hypothesis for ozone loss are considered and a simplified description of the behavior of Antarctic ozone in winter and spring is given. Evidence that the situation is more complicated than described by the theory is produced. Many unresolved scientific issues remain and some of the most important problems are identified. Ozone changes each spring since 1979 have clearly established for the first time that man made chlorine compounds influence stratospheric ozone. Long before important advances in satellite and in situ investigations, it was Dobson's decision to place a total ozone measuring spectrometer at Halley Bay in Antarctica during the International Geophysical Year and subsequent continuous monitoring which led to the discovery that ozone was being destroyed each spring by chlorine processed by polar stratospheric clouds.

  10. Polarizing cues.

    PubMed

    Nicholson, Stephen P

    2012-01-01

    People categorize themselves and others, creating ingroup and outgroup distinctions. In American politics, parties constitute the in- and outgroups, and party leaders hold sway in articulating party positions. A party leader's endorsement of a policy can be persuasive, inducing co-partisans to take the same position. In contrast, a party leader's endorsement may polarize opinion, inducing out-party identifiers to take a contrary position. Using survey experiments from the 2008 presidential election, I examine whether in- and out-party candidate cues—John McCain and Barack Obama—affected partisan opinion. The results indicate that in-party leader cues do not persuade but that out-party leader cues polarize. This finding holds in an experiment featuring President Bush in which his endorsement did not persuade Republicans but it polarized Democrats. Lastly, I compare the effect of party leader cues to party label cues. The results suggest that politicians, not parties, function as polarizing cues. PMID:22400143

  11. Polar motion

    NASA Technical Reports Server (NTRS)

    Kolenkiewicz, R.

    1973-01-01

    Tracking of the Beacon Explorer-C satellite by a precision laser system was used to measure the polar motion and solid earth tide. The tidal perturbation of satellite latitude is plotted as variation in maximum latitude in seconds of arc on earth's surface as a function of the date, and polar motion is shown by plotting the variation in latitude of the laser in seconds of arc along the earth's surface as a function of date

  12. E166: Polarized Positrons & Polarimetry

    SciTech Connect

    Schuler, K.Peter; /DESY

    2011-12-06

    A proof-of-principle experiment has been carried out in the Final Focus Test Beam (FFTB) at Stanford Linear Accelerator Center (SLAC) to demonstrate production of polarized positrons in a manner suitable for implementation at the International Linear Collider (ILC). A helical undulator of 2.54 mm period and 1 -m length produced circularly polarized photons with a first harmonic endpoint energy of 8 MeV when traversed by a 46.6 GeV electron beam. The polarized photons were converted to polarized positrons in a 0.2-radiation-length tungsten target. The polarization of these positrons was measured using a Compton transmission polarimeter to have peak value in excess of 80%.

  13. Students and Teachers Exploring Local Landscapes to Interpret the Earth from Space Application to the International Polar Year (SATELLITES-IPY Application)

    NASA Astrophysics Data System (ADS)

    Czajkowski, K.; Hedley, M.; Benko, T.

    2007-12-01

    The SATELLITES Program was established in 1999 at the University of Toledo to engage students in "real science" and introduce Earth System Science and geospatial technologies into the K-12 environment. The SATELLITES Program has now expanded to include scientists from the OhioView Remote Sensing Consortium, teachers from over 200 schools and reaches students in countries from around the world through the GLOBE program. SATELLITES is made up of four parts 1. the Observing Earth from Space Summer Institute, 2. a fall field intensive through the GLOBE program to engage students in observing their environment, 3. a spring inquiry- based application project in which the students address an environmental question using the observations that they took and that other students at other schools in the GLOBE network have taken, and 4. the SATELLITES Conference where students present their inquiry-based projects. The week-long SATELITES summer Institute introduces teachers to geospatial technologies of GIS, GPS and remote sensing. Content knowledge is built through interactions with scientists and everything is linked to the Standards. Through the field campaign, students focus on observing locally to understand the global issues of the polar regions and melting of ice and snow.

  14. Polar Stratigraphy

    NASA Technical Reports Server (NTRS)

    1999-01-01

    These three images were taken on three different orbits over the north polar cap in April 1999. Each shows a different part of the same ice-free trough. The left and right images are separated by a distance of more than 100 kilometers (62 miles). Note the similar layers in each image.

  15. Political polarization

    PubMed Central

    Dixit, Avinash K.; Weibull, Jörgen W.

    2007-01-01

    Failures of government policies often provoke opposite reactions from citizens; some call for a reversal of the policy, whereas others favor its continuation in stronger form. We offer an explanation of such polarization, based on a natural bimodality of preferences in political and economic contexts and consistent with Bayesian rationality. PMID:17452633

  16. Polarized Sources, Targets and Polarimetry

    NASA Astrophysics Data System (ADS)

    Ciullo, Guiseppe; Contalbrigo, Marco; Lenisa, P.

    2011-01-01

    filtering studies at COSY and CERN/AD / C. Barschel -- First experiments with the polarized internal gas target at ANKE/COSY / M. Mikirtychyants -- Extra physics with an ABS and a Lamb-shift polarimeter / R. Engels -- Systematic studies for the development of high-intensity ABS / L. Barion -- Upgrade of the 50 keV GaAs source of polarized electrons at ELSA / D. Heiliger -- Lifetime measurements of DBR and nonDBR photocathodes at high laser intensities / E. Riehn -- Polarized electron source based on FZD SRF gun / R. Xiang -- Major advances in SEOP of [symbol]He targets / P. Dolph -- A study of polarized metastable [symbol]He beam production / Yu. A. Plis -- Polarized [symbol]He targets for real and virtual photons / J. Krimmer -- Spin-filtering studies at COSY and AD / F. Rathmann -- Experimental setup for spin-filtering studies at COSY and AD / A. Nass -- Polarizing a stored proton beam by spin-flip? - A reanalysis / D. Oellers -- Tracking studies of spin coherence in COSY in view of EDM polarization measurements / A. U. Luccio -- Summary of the XIII international workshop on polarized sources, targets and polarimetry / F. Rathmann.

  17. Opportunities with polarized beam & target

    NASA Astrophysics Data System (ADS)

    Miyachi, Yoshiyuki

    2014-09-01

    Single spin asymmetries in Drell-Yan (DY) scattering, which are going to be measured in the present and planned polarized DY experiments, gain further insight into the internal structure of the nucleon. For the novel Sivers distribution function, the possible sign change in DY and Semi-Inclusive Deep-Inelastic-Scattering (SIDIS) may be confirmed for the first time, which is a critical test of the transverse momentum dependent (TMD) factorization in QCD, and precise information on the sea quarks, which are less sensitive in DIS, will be obtained. Since DY is one of the cleanest hard scattering processes, where no hadron fragmentation involved, it does not require information on hadron fragmentation functions (FF) to extract TMD PDF from the observed azimuthal amplitudes, where TMD PDF appears along with a corresponding FF in the case of SIDIS. Various azimuthal amplitudes of un-polarized cross section and singly-polarized or doubly-polarized cross section asymmetries in SIDIS have been measured. Double spin asymmetry in DY where beam and target are polarized is another unique tool to study TMD PDFs directly and it is a complementary measurement to SIDIS toward the complete description of the nucleon. Single spin asymmetries of the W-production cross section in the polarized proton-proton collision, recently measured at the RHIC/spin program, indicate the possible quark flavor symmetry violation in the polarized light-sea. Similar flavor asymmetry in the un-polarized light-sea, known as violation of the Gottfried sum rule, is currently studied at the on-going DY experiment SeaQuest at Fermilab. The observed flavor asymmetries can be a key to understand non-perturbative structure of the nucleon. With double spin asymmetry measurements in longitudinally polarized DY the flavor asymmetry in the polarized sea can be confirmed. In the presentation, physics cases which can be studied in doubly polarized DY and related topics will be discussed.

  18. Cell polarity

    PubMed Central

    Romereim, Sarah M

    2011-01-01

    Despite extensive genetic analysis of the dynamic multi-phase process that transforms a small population of lateral plate mesoderm into the mature limb skeleton, the mechanisms by which signaling pathways regulate cellular behaviors to generate morphogenetic forces are not known. Recently, a series of papers have offered the intriguing possibility that regulated cell polarity fine-tunes the morphogenetic process via orienting cell axes, division planes and cell movements. Wnt5a-mediated non-canonical signaling, which may include planar cell polarity, has emerged as a common thread in the otherwise distinct signaling networks that regulate morphogenesis in each phase of limb development. These findings position the limb as a key model to elucidate how global tissue patterning pathways direct local differences in cell behavior that, in turn, generate growth and form. PMID:22064549

  19. Polar Textures

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Context image for PIA03646 Polar Textures

    This VIS image shows part of the south polar region. The ejecta from the relatively young crater covers the rougher textured polar surface.

    Image information: VIS instrument. Latitude 81S, Longitude 54.5E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  20. Multifractal detrended cross-correlation between the Chinese domestic and international gold markets based on DCCA and DMCA methods

    NASA Astrophysics Data System (ADS)

    Cao, Guangxi; Han, Yan; Chen, Yuemeng; Yang, Chunxia

    2014-05-01

    Based on the daily price data of Shanghai and London gold spot markets, we applied detrended cross-correlation analysis (DCCA) and detrended moving average cross-correlation analysis (DMCA) methods to quantify power-law cross-correlation between domestic and international gold markets. Results show that the cross-correlations between the Chinese domestic and international gold spot markets are multifractal. Furthermore, forward DMCA and backward DMCA seems to outperform DCCA and centered DMCA for short-range gold series, which confirms the comparison results of short-range artificial data in L. Y. He and S. P. Chen [Physica A 390 (2011) 3806-3814]. Finally, we analyzed the local multifractal characteristics of the cross-correlation between Chinese domestic and international gold markets. We show that multifractal characteristics of the cross-correlation between the Chinese domestic and international gold markets are time-varying and that multifractal characteristics were strengthened by the financial crisis in 2007-2008.

  1. Polar Landforms

    NASA Technical Reports Server (NTRS)

    2005-01-01

    10 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows eroded remnants of carbon dioxide ice in the south polar residual cap of Mars. The scarps that outline each small mesa have retreated about 3 meters (10 feet) per Mars year since MGS began orbiting the red planet in 1997.

    Location near: 87.0oS, 31.9oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  2. Polar Markings

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA02155 Polar Markings

    These bright and dark markings occurred near the end of summer in the south polar region. The dark material is likely dust that has been freed of frost cover.

    Image information: VIS instrument. Latitude -76.3N, Longitude 84.9E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  3. Polar Layers

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA02153 Polar Layers

    This image of the south polar region shows layered material. It is not known if the layers are formed yearly or if they form over the period of 10s to 100s of years or more.

    Image information: VIS instrument. Latitude -80.3N, Longitude 296.2E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  4. Polar Ridges

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA03662 Polar Ridges

    This ridge system is located in the south polar region.

    Image information: VIS instrument. Latitude -81.7N, Longitude 296.5E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  5. Polar Textures

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Context image for PIA03638 Polar Textures

    This image illustrates the variety of textures that appear in the south polar region during late summer.

    Image information: VIS instrument. Latitude 80.5S, Longitude 57.9E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  6. Polar Terrains

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Context image for PIA03577 Polar Terrains

    The region surrounding the South Polar Cap contains many different terrain types. This image shows both etched terrain and a region of 'mounds'.

    Image information: VIS instrument. Latitude 75S, Longitude 286.5E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  7. Data acquisition system for the BESS-Polar experiment

    NASA Astrophysics Data System (ADS)

    Orito, Reiko

    The Balloon-borne experiment with a superconducting spectrometer on a long duration balloon flight in Antarctica (BESS-Polar) has been carried out to investigate elementary particle phenomena in the early universe through the measurement of cosmic-ray antiparticles[1]. To realize the long term observation over 20 days, the data acquisition system(DAQ) for the BESS-Polar spectrometer has been newly developed with a base of previous BESS-DAQ[2]. The BESS-Polar DAQ system consists of low-power front end electronics(FEE)[3], high speed processors, large capacity data storage, telemetry communicating system, monitors for the spectrometer, and the solar-panel power supply system. The data from the FEEs(TDCs, QDCs, FADCs) are converted to USB2.0 signal and sent to the dual core processor with a CompactPCI bus. The event is built(˜3k byte/event) and recorded to the data storage with an array of sixteen 1TB-HDDs. The data recording system is installed in the compact pressurized data vessel with a proper thermal treatment. The dead time of data acquisition was below 20% at 2.5kHz trigger rate during the flight. The total power consumption of the BESS- Polar spectrometer was 500W. The power lines from the solar panels to the spectrometer are controlled by the programmable TOSHIBA Neuron chips and the low-power PC104 system. The monitor data and the telemetry are also received by original modules on the PC104 system. This system was operated during the scientific run for 24.5 days over Antarctica and successfully recorded 4.6 billion cosmic-ray events during the solar minimum period in 2007-2008. All the DAQ system was well operated without any critical problem. In this presentation, the DAQ system for the BESS-Polar experiment and its performances will be reported. References: [1] A.Yamamoto et al., Nuclear Physics B, Vol.166, 2007, pp.62-67 [2] Y. Ajima et al., Nucl. Instr. and Methods , A 443, 2000, pp.71-100 [3] M.Sasaki et al., 29th ICRC, Pune (2005) 3, pp.421-424

  8. Antimatter and Dark Matter Search in Space: BESS-Polar Results

    NASA Technical Reports Server (NTRS)

    Mitchell, John W.; Yamamoto, Akira

    2009-01-01

    The apex of the Balloon-borne Experiment with a Superconducting Spectrometer program was reached with the Antarctic flight of BESS-Polar II, during the 2007-2008 Austral Summer, that obtained 24.5 days of data on over 4.7 billion cosmic-ray events. The US-Japan BESS Collaboration uses elementary particle measurements to study the early Universe and provides fundamental data on the spectra of light cosmic-ray elements and isotopes. BESS measures the energy spectra of cosmic-ray antiprotons to investigate signatures of possible exotic sources, such as dark-matter candidates, and searches for heavier anti-nuclei that might reach Earth from antimatter domains formed during symmetry breaking processes in the early Universe. Since 1993, BESS has carried out eleven high-latitude balloon flights, two of long duration, that together have defined the study of antiprotons below about 4 GeV, provided standard references for light element and isotope spectra, and set the most sensitive limits on the existence of anti-deuterons and anti-helium, The BESS-Polar II flight took place at Solar Minimum, when the sensitivity of the low-energy antiproton measurements to a primary source is greatest. The rich BESS-Polar II dataset more than doubles the combined data from all earlier BESS flights and has 10-20 times the statistics of BESS data from the previous Solar Minimum. Here, we summarize the scientific results of BESS program, focusing on the results obtained using data from the long-duration flights of BESS-Polar I (2004) and BESS-Polar II.

  9. Polar Barchans

    NASA Technical Reports Server (NTRS)

    2004-01-01

    20 July 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark, barchan sand dunes of the north polar region of Mars. Barchan dunes are simple, rounded forms with two horns that extend downwind. Inequalities in local wind patterns may result in one horn being extended farther than the other, as is the case for several dunes in this image. The image also shows several barchans may merge to form a long dune ridge. The horns and attendant slip faces on these dunes indicate wind transport of sand from the upper left toward the lower right. The image is located near 77.6oN, 103.6oW. The picture covers an area about 3 km (1.9 mi) wide; sunlight illuminates the scene from the lower left.

  10. Polar Polygons

    NASA Technical Reports Server (NTRS)

    2004-01-01

    26 December 2003 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture displays polygons outlined by cracks in the martian south polar region. This southern summer view was acquired in October 2003 and is located near 86.9oS, 170.6oW. Polygons similar in size and shape to these are common in the arctic and antarctic regions of Earth. On Earth, they indicate the presence (or the past presence) of ground ice and the freeze-thaw cycles that accompany this ice. On Mars, whether ground ice was responsible for these landforms is uncertain, but their presence is suggestive that ground ice may exist or may once have existed in this region. The picture covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the upper left.

  11. HERMES measurements of {lambda} polarization

    SciTech Connect

    Rith, Klaus

    2007-06-13

    The HERMES experiment at DESY has measured the transfer of polarization from longitudinally polarized 27.6 GeV positrons to {lambda} hyperons produced in semi-inclusive deep-inelastic scattering from unpolarized gas targets internal to the electron/positron ring of the HERA collider. The longitudinal spin transfer coefficient is found to be D{sub LL'}{sup {lambda}} = 0.11 {+-} 0.10 (stat) {+-} 0.03 (syst) at an average fractional energy carried by the {lambda} hyperon = 0.45.

  12. Italian Polar Metadata System

    NASA Astrophysics Data System (ADS)

    Longo, S.; Nativi, S.; Leone, C.; Migliorini, S.; Mazari Villanova, L.

    2012-04-01

    Italian Polar Metadata System C.Leone, S.Longo, S.Migliorini, L.Mazari Villanova, S. Nativi The Italian Antarctic Research Programme (PNRA) is a government initiative funding and coordinating scientific research activities in polar regions. PNRA manages two scientific Stations in Antarctica - Concordia (Dome C), jointly operated with the French Polar Institute "Paul Emile Victor", and Mario Zucchelli (Terra Nova Bay, Southern Victoria Land). In addition National Research Council of Italy (CNR) manages one scientific Station in the Arctic Circle (Ny-Alesund-Svalbard Islands), named Dirigibile Italia. PNRA started in 1985 with the first Italian Expedition in Antarctica. Since then each research group has collected data regarding biology and medicine, geodetic observatory, geophysics, geology, glaciology, physics and atmospheric chemistry, earth-sun relationships and astrophysics, oceanography and marine environment, chemistry contamination, law and geographic science, technology, multi and inter disciplinary researches, autonomously with different formats. In 2010 the Italian Ministry of Research assigned the scientific coordination of the Programme to CNR, which is in charge of the management and sharing of the scientific results carried out in the framework of the PNRA. Therefore, CNR is establishing a new distributed cyber(e)-infrastructure to collect, manage, publish and share polar research results. This is a service-based infrastructure building on Web technologies to implement resources (i.e. data, services and documents) discovery, access and visualization; in addition, semantic-enabled functionalities will be provided. The architecture applies the "System of Systems" principles to build incrementally on the existing systems by supplementing but not supplanting their mandates and governance arrangements. This allows to keep the existing capacities as autonomous as possible. This cyber(e)-infrastructure implements multi-disciplinary interoperability following

  13. The International Heliophysical Year

    NASA Technical Reports Server (NTRS)

    Thompson, Barbara J.

    2007-01-01

    In 1957 a program of international research, inspired by the International Polar Years of 1882 and 1932, was organized as the International Geophysical Year (IGY) to study global phenomena of the Earth and geospace. Fifty years later, the world s space science community will again come together for international programs of scientific collaboration: the International Heliophysical Year (IHY), the Electronic Geophysical Year (eGY), and the International Polar Year (IPY) 2007. This time, research will extend out into the Heliosphere to focus on solar-terrestrial-planetary interactions. The ambitious plans for the IHY, eGY and IPY incorporate the activities of scientists in 191 nations, as well as the IGY Gold Historical Preservation initiative, plus a series of coordinated campaigns involving more than 100 instruments and models, education and public outreach programs, a developing nations instrument development program, and opportunities for supported research worldwide. The presentation will focus on the efforts and operations which will make these activities possible.

  14. Polar Color

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released 3 May 2004 This nighttime visible color image was collected on January 1, 2003 during the Northern Summer season near the North Polar Troughs.

    This daytime visible color image was collected on September 4, 2002 during the Northern Spring season in Vastitas Borealis. The THEMIS VIS camera is capable of capturing color images of the martian surface using its five different color filters. In this mode of operation, the spatial resolution and coverage of the image must be reduced to accommodate the additional data volume produced from the use of multiple filters. To make a color image, three of the five filter images (each in grayscale) are selected. Each is contrast enhanced and then converted to a red, green, or blue intensity image. These three images are then combined to produce a full color, single image. Because the THEMIS color filters don't span the full range of colors seen by the human eye, a color THEMIS image does not represent true color. Also, because each single-filter image is contrast enhanced before inclusion in the three-color image, the apparent color variation of the scene is exaggerated. Nevertheless, the color variation that does appear is representative of some change in color, however subtle, in the actual scene. Note that the long edges of THEMIS color images typically contain color artifacts that do not represent surface variation.

    Image information: VIS instrument. Latitude 79, Longitude 346 East (14 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with

  15. Beam Polarization at the ILC: Physics Case and Realization

    NASA Astrophysics Data System (ADS)

    Vauth, Annika; List, Jenny

    2016-02-01

    The International Linear Collider (ILC) is a proposed e+e‑ collider, focused on precision measurement of the Standard Model and new physics beyond. Polarized beams are a key element of the ILC physics program. The physics studies are accompanied by an extensive R&D program for the creation of the polarized beams and the measurement of their polarization. This contribution will review the advantages of using beam polarization and its technical aspects and realization, such as the creation of polarized beams and the measurement of the polarization.

  16. Polar metals by geometric design

    NASA Astrophysics Data System (ADS)

    Kim, T. H.; Puggioni, D.; Yuan, Y.; Xie, L.; Zhou, H.; Campbell, N.; Ryan, P. J.; Choi, Y.; Kim, J.-W.; Patzner, J. R.; Ryu, S.; Podkaminer, J. P.; Irwin, J.; Ma, Y.; Fennie, C. J.; Rzchowski, M. S.; Pan, X. Q.; Gopalan, V.; Rondinelli, J. M.; Eom, C. B.

    2016-05-01

    Gauss’s law dictates that the net electric field inside a conductor in electrostatic equilibrium is zero by effective charge screening; free carriers within a metal eliminate internal dipoles that may arise owing to asymmetric charge distributions. Quantum physics supports this view, demonstrating that delocalized electrons make a static macroscopic polarization, an ill-defined quantity in metals—it is exceedingly unusual to find a polar metal that exhibits long-range ordered dipoles owing to cooperative atomic displacements aligned from dipolar interactions as in insulating phases. Here we describe the quantum mechanical design and experimental realization of room-temperature polar metals in thin-film ANiO3 perovskite nickelates using a strategy based on atomic-scale control of inversion-preserving (centric) displacements. We predict with ab initio calculations that cooperative polar A cation displacements are geometrically stabilized with a non-equilibrium amplitude and tilt pattern of the corner-connected NiO6 octahedra—the structural signatures of perovskites—owing to geometric constraints imposed by the underlying substrate. Heteroepitaxial thin-films grown on LaAlO3 (111) substrates fulfil the design principles. We achieve both a conducting polar monoclinic oxide that is inaccessible in compositionally identical films grown on (001) substrates, and observe a hidden, previously unreported, non-equilibrium structure in thin-film geometries. We expect that the geometric stabilization approach will provide novel avenues for realizing new multifunctional materials with unusual coexisting properties.

  17. Polarized Light in Astronomy.

    ERIC Educational Resources Information Center

    King, D. J.

    1983-01-01

    The application of very sensitive electronic detecting devices during the last decade has revolutionized and revitalized the study of polarization in celestial objects. The nature of polarization, how polaroids work, interstellar polarization, dichroic filters, polarization by scattering, and modern polarimetry are among the topics discussed. (JN)

  18. Linearly polarized fiber amplifier

    DOEpatents

    Kliner, Dahv A.; Koplow, Jeffery P.

    2004-11-30

    Optically pumped rare-earth-doped polarizing fibers exhibit significantly higher gain for one linear polarization state than for the orthogonal state. Such a fiber can be used to construct a single-polarization fiber laser, amplifier, or amplified-spontaneous-emission (ASE) source without the need for additional optical components to obtain stable, linearly polarized operation.

  19. Alaskan Exemplary Program The Rural Alaska Honors Institute (RAHI) A Quarter Century of Success of Educating, Nurturing, and Retaining Alaska Native and Rural Students An International Polar Year Adventure in Barrow

    NASA Astrophysics Data System (ADS)

    Wartes, D.; Owens, G.

    2007-12-01

    UA system who participated in RAHI are nearly twice as likely to earn a bachelors degree, than those who did not attend RAHI. This summer, in celebration of the International Polar Year, in collaboration with Ilisagvik College, at the completion of the traditional RAHI program, ten RAHI students flew to Barrow for an additional two weeks of study. Five students participated in an archaeological dig and five students performed research with the Barrow Arctic Science Consortium scientists studying climate change. In addition, ten students from Greenland visited the program, with plans to more fully participate next summer. This added dimension to the program has proved successful, allowing the students to compare and contrast between their own countries and indigenous perspectives. Global warming was an issue that was hotly debated, as its effects are so evident in the Polar Regions. In the Arctic, life is directly tied to the ice and snow. As the ice disappears and/or changes, the Indigenous people have to adapt. RAHI would like to share with you some of the results of this past summers IPY activities.

  20. Nondiffracting transversally polarized beam.

    PubMed

    Yuan, G H; Wei, S B; Yuan, X-C

    2011-09-01

    Generation of a nondiffracting transversally polarized beam by means of transmitting an azimuthally polarized beam through a multibelt spiral phase hologram and then highly focusing by a high-NA lens is presented. A relatively long depth of focus (∼4.84λ) of the electric field with only radial and azimuthal components is achieved. The polarization of the wavefront near the focal plane is analyzed in detail by calculating the Stokes polarization parameters. It is found that the polarization is spatially varying and entirely transversally polarized, and the polarization singularity disappears at the beam center, which makes the central bright channel possible. PMID:21886250

  1. Crossed elliptical polarization undulator

    SciTech Connect

    Sasaki, Shigemi

    1997-05-01

    The first switching of polarization direction is possible by installing two identical helical undulators in series in a same straight section in a storage ring. By setting each undulator in a circular polarization mode in opposite handedness, one can obtain linearly polarized radiation with any required polarization direction depending on the modulator setting between two undulators. This scheme can be used without any major degradation of polarization degree in any low energy low emittance storage ring.

  2. Polarization-balanced beamsplitter

    DOEpatents

    Decker, D.E.

    1998-02-17

    A beamsplitter assembly is disclosed that includes several beamsplitter cubes arranged to define a plurality of polarization-balanced light paths. Each polarization-balanced light path contains one or more balanced pairs of light paths, where each balanced pair of light paths includes either two transmission light paths with orthogonal polarization effects or two reflection light paths with orthogonal polarization effects. The orthogonal pairing of said transmission and reflection light paths cancels polarization effects otherwise caused by beamsplitting. 10 figs.

  3. Polarization-balanced beamsplitter

    DOEpatents

    Decker, Derek E.

    1998-01-01

    A beamsplitter assembly that includes several beamsplitter cubes arranged to define a plurality of polarization-balanced light paths. Each polarization-balanced light path contains one or more balanced pairs of light paths, where each balanced pair of light paths includes either two transmission light paths with orthogonal polarization effects or two reflection light paths with orthogonal polarization effects. The orthogonal pairing of said transmission and reflection light paths cancels polarization effects otherwise caused by beamsplitting.

  4. Neutron polarizers based on polarized ^3He

    NASA Astrophysics Data System (ADS)

    Gentile, T. R.; Jones, G. L.; Thompson, A. K.; Fei, X.; Keith, C. D.; Rich, D.; Snow, W. M.; Penttila, S.

    1997-10-01

    Research is underway at NIST, Indiana Univ., and LANL to develop neutron polarizers and analyzers based on polarized ^3He. Such devices, which rely on the strong spin dependence of the neutron capture cross section by polarized ^3He, have applications in weak interaction physics and materials science. In addition, the technology for polarized ^3He production is directly applicable to polarized gas MRI of lungs, and polarized targets. Our program, which includes both the spin-exchange and metastability-exchange optical pumping methods, will be reviewed. Spin-exchange has been used to analyze a polarized cold neutron beam at NIST, and also for lung imaging in collaboration with the Univ. of Pennsylvania. In the metastable method, the ^3He is polarized at low pressure, and must be substantially compressed. A piston compressor has been designed for this goal at Indiana Univ. and is under construction. At NIST we have compressed polarized gas using an apparatus that is based on a modified commercial diaphragm pump.

  5. Polar Contests for the IPY: a Youth Steering Committee Project

    NASA Astrophysics Data System (ADS)

    Raymond, M.; Senger, K.; Haase, D.; Kaiser, B.; Gonsior, M.; Salmon, R.

    2006-12-01

    The Polar Contests are a project being initiated by the International Youth Steering Committee (YSC) for the International Polar Year. Two aims integral to the YSC are firstly the networking of young polar researchers across disciplines early in their careers to enable collaboration, and secondly for this network to be involved in outreach to other youth. To meet these two aims with a project coordinated by youth for youth, the YSC will be running Polar Contests pioneered by the New Zealand committee. These contests will run in high schools during 2007, aiming to encourage young people to learn about polar research and express their views on the Polar Regions in as creative of a way as possible. A network of young polar researchers is being formed, and is supported by a website facilitating communication and alliance within this group. This network is also producing teaching resources reflecting the research and polar experiences of its members. These will be compiled into packs and distributed to high schools to inspire youth to produce entries for a Youth Polar Exhibition to tour museums during IPY. Entries will take a wide variety of forms, from artworks to research posters to equipment designs, reflecting the diversity of research and art connected to the poles. The entries to the New Zealand Polar Contests will be exhibited at the International Youth Conference on the Poles, May 2008. Although currently a New Zealand project, we anticipate that the Polar Contests will provide a useful model to be adopted by other countries involved in IPY.

  6. Changing polar environments: Interdisciplinary challenges

    NASA Astrophysics Data System (ADS)

    Shepson, Paul B.; Ariya, Parisa A.; Deal, Clara J.; Donaldson, D. James; Douglas, Thomas A.; Loose, Brice; Maksym, Ted; Matrai, Patricia A.; Russell, Lynn M.; Saenz, Benjamin; Stefels, Jacqueline; Steiner, Nadja

    2012-03-01

    In the past few decades, there has been enormous growth in scientific studies of physical, chemical, and biological interactions among reservoirs in polar regions. This has come, in part, as a result of a few significant discoveries: There is dramatic halogen chemistry that occurs on and above the sea ice in the springtime that destroys lower tropospheric ozone and mercury [Simpson et al., 2007; Steffen et al., 2008], the sunlit snowpack is very photochemically active [Grannas et al., 2007], biology as a source of organic compounds plays a pivotal role in these processes, and these processes are occurring in the context of rapidly changing polar regions under climate feedbacks that are as of yet not fully understood [Serreze and Barry, 2011]. Stimulated by the opportunities of the International Polar Year (IPY, 2007-2009), a number of large-scale field studies in both polar environments have been undertaken, aimed at the study of the complex biotic and abiotic processes occurring in all phases (see Figure 1). Sea ice plays a critical role in polar environments: It is a highly reflective surface that interacts with radiation; it provides a habitat for mammals and micro-organisms alike, thus playing a key role in polar trophic processes and elemental cycles; and it creates a saline environment for chemical processes that facilitate release of halogenated gases that contribute to the atmosphere's ability to photochemically cleanse itself in an otherwise low-radiation environment. Ocean-air and sea ice-air interfaces also produce aerosol particles that provide cloud condensation nuclei.

  7. Polarized Light Corridor Demonstrations.

    ERIC Educational Resources Information Center

    Davies, G. R.

    1990-01-01

    Eleven demonstrations of light polarization are presented. Each includes a brief description of the apparatus and the effect demonstrated. Illustrated are strain patterns, reflection, scattering, the Faraday Effect, interference, double refraction, the polarizing microscope, and optical activity. (CW)

  8. Polarization at SLAC

    SciTech Connect

    Woods, M.

    1995-01-01

    A highly polarized electron beam is a key feature. for the Current physics program at SLAC. An electron beam polarization of 80% can now be routinely achieved for typically 5000 hours of machine operation per year. Two main Physics programs utilize the polarized beam. Fixed target experiments in End Station A study the collision of polarized electrons with polarized nuclear targets to elucidate the spin structure of the nucleon and to provide an important test of QCD. Using the SLAC Linear Collider, collisions of polarized electrons with unpolarized positrons allow precise measurements of parity violation in the Z-fermion couplings and provide a very precise measurement of tile weak mixing angle. This paper discusses polarized beam operation at SLAC, and gives an overview of the polarized physics program.

  9. A Translational Polarization Rotator

    NASA Technical Reports Server (NTRS)

    Chuss, David T.; Wollack, Edward J.; Pisano, Giampaolo; Ackiss, Sheridan; U-Yen, Kongpop; Ng, Ming wah

    2012-01-01

    We explore a free-space polarization modulator in which a variable phase introduction between right- and left-handed circular polarization components is used to rotate the linear polarization of the outgoing beam relative to that of the incoming beam. In this device, the polarization states are separated by a circular polarizer that consists of a quarter-wave plate in combination with a wire grid. A movable mirror is positioned behind and parallel to the circular polarizer. As the polarizer-mirror distance is separated, an incident liear polarization will be rotated through an angle that is proportional to the introduced phase delay. We demonstrate a prototype device that modulates Stokes Q and U over a 20% bandwidth.

  10. Scientific capabilities of POLAR and its coordinated observation program

    NASA Astrophysics Data System (ADS)

    Zhang, Shuang-Nan

    2016-07-01

    POLAR is a compact polarimeter dedicated to measuring the polarization of gamma-ray bursts (GRBs) and other bright hard X-ray and low energy gamma-ray sources between 50-350 keV wth a very large field of view, to be launched in September 2016 onboard China's Tianggong-2 spacelab. On behalf of the international POLAR collaboration team between China, Switzerland and Poland, I will summarize the scientific capabilities of POLAR and its coordinated observation program, including releasing promptly the estimated sensitivity to each GRB triggered by other instruments and in the field of view of POLAR.

  11. Polar Ozone Workshop. Abstracts

    NASA Technical Reports Server (NTRS)

    Aikin, Arthur C.

    1988-01-01

    Results of the proceedings of the Polar Ozone Workshop held in Snowmass, CO, on May 9 to 13, 1988 are given. Topics covered include ozone depletion, ozonometry, polar meteorology, polar stratospheric clouds, remote sensing of trace gases, atmospheric chemistry and dynamical simulations.

  12. Hybrid polarization control

    NASA Astrophysics Data System (ADS)

    Gray, George R.; Ibragimov, Edem; Sluz, Joseph; Sova, Raymond

    2005-05-01

    We demonstrate a novel method of polarization control that combines rotatable waveplates (angle control) and variable retarders (retardance control). Such a "hybrid" polarization controller performs far better than conventional controllers, allowing nearly perfect arbitrary-to-arbitrary polarization transformations. We show theoretically that the two control parameters augment one another because they tend to result in orthogonal movements on the Poincaré sphere.

  13. Graphing Polar Curves

    ERIC Educational Resources Information Center

    Lawes, Jonathan F.

    2013-01-01

    Graphing polar curves typically involves a combination of three traditional techniques, all of which can be time-consuming and tedious. However, an alternative method--graphing the polar function on a rectangular plane--simplifies graphing, increases student understanding of the polar coordinate system, and reinforces graphing techniques learned…

  14. Playing with Polarizers.

    ERIC Educational Resources Information Center

    Hecht, Jeff

    1991-01-01

    Discussed is how polarized sunglasses block glare, help spot subtle differences in surfaces, and give a clearer view under water. Information on unpolarized and polarized light is provided. The reasons causing glare to occur and how polarizers decrease glare are discussed. (KR)

  15. Polarity at Many Levels

    ERIC Educational Resources Information Center

    Flannery, Maura C.

    2004-01-01

    An attempt is made to find how polarity arises and is maintained, which is a central issue in development. It is a fundamental attribute of living things and cellular polarity is also important in the development of multicellular organisms and controversial new work indicates that polarization in mammals may occur much earlier than previously…

  16. Physics with Polarized Nuclei.

    ERIC Educational Resources Information Center

    Thompson, William J.; Clegg, Thomas B.

    1979-01-01

    Discusses recent advances in polarization techniques, specifically those dealing with polarization of atomic nuclei, and how polarized beams and targets are produced. These techniques have greatly increased the scope of possible studies, and provided the tools for testing fundamental symmetries and the spin dependence of nuclear forces. (GA)

  17. Bumblebees Learn Polarization Patterns

    PubMed Central

    Foster, James J.; Sharkey, Camilla R.; Gaworska, Alicia V.A.; Roberts, Nicholas W.; Whitney, Heather M.; Partridge, Julian C.

    2014-01-01

    Summary Foraging insect pollinators such as bees must find and identify flowers in a complex visual environment. Bees use skylight polarization patterns for navigation [1–3], a capacity mediated by the polarization-sensitive dorsal rim area (DRA) of their eye [4, 5]. While other insects use polarization sensitivity to identify appropriate habitats [6], oviposition sites, and food sources [7], to date no nonnavigational functions of polarization vision have been identified in bees. Here we investigated the ability of bumblebees (Bombus terrestris) to learn polarization patterns on artificial “flowers” in order to obtain a food reward. We show that foraging bumblebees can learn to discriminate between two differently polarized targets, but only when the target artificial “flower” is viewed from below. A context for these results is provided by polarization imaging of bee-pollinated flowers, revealing the potential for polarization patterns in real flowers. Bees may therefore have the ability to use polarization vision, possibly mediated by their polarization-sensitive DRA, both for navigation and to learn polarization patterns on flowers, the latter being the first nonnavigational function for bee polarization vision to be identified. PMID:24909321

  18. Polarization feedback laser stabilization

    DOEpatents

    Esherick, Peter; Owyoung, Adelbert

    1988-01-01

    A system for locking two Nd:YAG laser oscillators includes an optical path for feeding the output of one laser into the other with different polarizations. Elliptical polarization is incorporated into the optical path so that the change in polarization that occurs when the frequencies coincide may be detected to provide a feedback signal to control one laser relative to the other.

  19. Calculation of polarization effects

    SciTech Connect

    Chao, A.W.

    1983-09-01

    Basically there are two areas of accelerator applications that involve beam polarization. One is the acceleration of a polarized beam (most likely a proton beam) in a synchrotron. Another concerns polarized beams in an electron storage ring. In both areas, numerical techniques have been very useful.

  20. Status of the hydrogen and deuterium atomic beam polarized target for NEPTUN experiment

    NASA Astrophysics Data System (ADS)

    Balandikov, N. I.; Ershov, V. P.; Fimushkin, V. V.; Kulikov, M. V.; Pilipenko, Yu. K.; Shutov, V. B.

    1995-09-01

    NEPTUN-NEPTUN-A is a polarized experiment at Accelerating and Storage Complex (UNK, IHEP) with two internal targets. Status of the atomic beam polarized target that is being developed at the Joint Institute for Nuclear Research, Dubna is presented.

  1. Freeing data through The Polar Information Commons

    NASA Astrophysics Data System (ADS)

    de Bruin, Taco; Chen, Robert; Parsons, Mark; Carlson, David

    2010-05-01

    The polar regions are changing rapidly with dramatic global effect. Wise management of resources, improved decision support, and effective international cooperation on resource and geopolitical issues require deeper understanding and better prediction of these changes. Unfortunately, polar data and information remain scattered, scarce, and sporadic. Inspired by the Antarctic Treaty of 1959 that established the Antarctic as a global commons to be used only for peaceful purposes and scientific research, we assert that data and information about the polar regions are themselves "public goods" that should be shared ethically and with minimal constraint. We therefore envision the Polar Information Commons (PIC) as an open, virtual repository for vital scientific data and information that would provide a shared, community-based cyber-infrastructure fostering innovation, improving scientific efficiency, and encouraging participation in polar research, education, planning, and management. The PIC will build on the legacy of the International Polar Year (IPY), providing a long-term framework for access to and preservation of both existing and future data and information about the polar regions. Rapid change demands rapid data access. The PIC system will enable scientists to quickly expose their data to the world and share them through open protocols on the Internet. A PIC digital label will alert users and data centers to new polar data and ensure that usage rights are clear. The PIC will utilize the Science Commons Protocol for Implementing Open Access Data, which promotes open data access through the public domain coupled with community norms of practice to ensure use of data in a fair and equitable manner. A set of PIC norms is currently being developed in consultation with key polar data organizations and other stakeholders. We welcome inputs from the broad science community as we further develop and refine the PIC approach and move ahead with implementation.

  2. Freeing data through The Polar Information Commons

    NASA Astrophysics Data System (ADS)

    de Bruin, T.; Chen, R. S.; Parsons, M. A.; Carlson, D. J.; Cass, K.; Finney, K.; Wilbanks, J.; Jochum, K.

    2010-12-01

    The polar regions are changing rapidly with dramatic global effect. Wise management of resources, improved decision support, and effective international cooperation on resource and geopolitical issues require deeper understanding and better prediction of these changes. Unfortunately, polar data and information remain scattered, scarce, and sporadic. Inspired by the Antarctic Treaty of 1959 that established the Antarctic as a global commons to be used only for peaceful purposes and scientific research, we assert that data and information about the polar regions are themselves “public goods” that should be shared ethically and with minimal constraint. ICSU’s Committee on Data (CODATA) therefore started the Polar Information Commons (PIC) as an open, virtual repository for vital scientific data and information. The PIC provides a shared, community-based cyber-infrastructure fostering innovation, improving scientific efficiency, and encouraging participation in polar research, education, planning, and management. The PIC builds on the legacy of the International Polar Year (IPY), providing a long-term framework for access to and preservation of both existing and future data and information about the polar regions. Rapid change demands rapid data access. The PIC system enables scientists to quickly expose their data to the world and share them through open protocols on the Internet. A PIC digital label will alert users and data centers to new polar data and ensure that usage rights are clear. The PIC utilizes the Science Commons Protocol for Implementing Open Access Data, which promotes open data access through the public domain coupled with community norms of practice to ensure use of data in a fair and equitable manner. A set of PIC norms has been developed in consultation with key polar data organizations and other stakeholders. We welcome inputs from the broad science community as we further develop and refine the PIC approach and move ahead with

  3. Freeing data through The Polar Information Commons

    NASA Astrophysics Data System (ADS)

    de Bruin, T.; Chen, R. S.; Parsons, M. A.; Carlson, D. J.

    2009-12-01

    The polar regions are changing rapidly with dramatic global effect. Wise management of resources, improved decision support, and effective international cooperation on resource and geopolitical issues require deeper understanding and better prediction of these changes. Unfortunately, polar data and information remain scattered, scarce, and sporadic. Inspired by the Antarctic Treaty of 1959 that established the Antarctic as a global commons to be used only for peaceful purposes and scientific research, we assert that data and information about the polar regions are themselves “public goods” that should be shared ethically and with minimal constraint. We therefore envision the Polar Information Commons (PIC) as an open, virtual repository for vital scientific data and information that would provide a shared, community-based cyber-infrastructure fostering innovation, improving scientific efficiency, and encouraging participation in polar research, education, planning, and management. The PIC will build on the legacy of the International Polar Year (IPY), providing a long-term framework for access to and preservation of both existing and future data and information about the polar regions. Rapid change demands rapid data access. The PIC system will enable scientists to quickly expose their data to the world and share them through open protocols on the Internet. A PIC digital label will alert users and data centers to new polar data and ensure that usage rights are clear. The PIC will utilize the Science Commons Protocol for Implementing Open Access Data, which promotes open data access through the public domain coupled with community norms of practice to ensure use of data in a fair and equitable manner. A set of PIC norms is currently being developed in consultation with key polar data organizations and other stakeholders. We welcome inputs from the broad science community as we further develop and refine the PIC approach and move ahead with implementation.

  4. Proceedings of the workshop on polarized targets in storage rings

    SciTech Connect

    Holt, R.J.

    1984-08-01

    Polarization phenomena have played an increasingly important part in the study of nuclei and nucleons in recent years. Polarization studies have been hampered by the relatively few and rather fragile polarized targets which are presently available. The concept of polarized gas targets in storage rings opens a much wider range of possibilities than is available in the external target geometry. This novel method will represent a considerable advance in nuclear physics and will continue to receive much attention in plans for future facilities. An internal, polarized-target station is being planned for the cooler ring at the Indiana University Cyclotron Facility. Internal targets are compatible with recent designs of electron accelerators proposed by the Massachusetts Institute of Technology and the Southeastern Universities Research Association. The key to nuclear-science programs based on internal targets pivots on recent developments in polarized atomic beam methods, which include the more recent laser-driven polarized targets. The workshop drew together a unique group of physicists in the fields of high-energy, nuclear and atomic physics. The meeting was organized in a manner that stimulated discussion among the 58 participants and focused on developments in polarized target technology and the underlying atomic physics. An impressive array of future possibilities for polarized targets as well as current developments in polarized target technology were discussed at the workshop. Abstracts of individual items from the workshop were prepared separately for the data base.

  5. Modeling the polar motion of Titan

    NASA Astrophysics Data System (ADS)

    Coyette, Alexis; Van Hoolst, Tim; Baland, Rose-Marie; Tokano, Tetsuya

    2016-02-01

    The angular momentum of the atmosphere and of the hydrocarbon lakes of Titan have a large equatorial component that can excite polar motion, a variable orientation of the rotation axis of Titan with respect to its surface. We here use the angular momentum obtained from a General Circulation Model of the atmosphere of Titan and from an Ocean Circulation Model for Titan's polar lakes to model the polar motion of Titan as a function of the interior structure. Besides the gravitational torque exerted by Saturn on Titan's aspherical mass distribution, the rotational model also includes torques arising due to the presence of an ocean under a thin ice shell as well as the influence of the elasticity of the different layers. The Chandler wobble period of a solid and rigid Titan without its atmosphere is about 279 years. The period of the Chandler wobble is mainly influenced by the atmosphere of Titan (-166 years) and the presence of an internal global ocean (+135 to 295 years depending on the internal model) and to a lesser extent by the elastic deformations (+3.7 years). The forced polar motion of a solid and rigid Titan is elliptical with an amplitude of about 50 m and a main period equal to the orbital period of Saturn. It is mainly forced by the atmosphere of Titan while the lakes of Titan are at the origin of a displacement of the mean polar motion, or polar offset. The subsurface ocean can largely increase the polar motion amplitude due to resonant amplification with a wobble free mode of Titan. The amplitudes as well as the main periods of the polar motion depend on whether and which forcing period is close to the period of a free mode. For a thick ice shell, the polar motion mainly has an annual period and an amplitude of about 1 km. For thinner ice shells, the polar motion amplitude can reach several tens of km and shorter periods become dominant. We demonstrate that for thick ice shells, the ice shell rigidity weakly influences the amplitude of the polar motion

  6. Composition law for polarizers

    NASA Astrophysics Data System (ADS)

    Lages, J.; Giust, R.; Vigoureux, J.-M.

    2008-09-01

    The polarization process when polarizers act on an optical field is studied. We give examples for two kinds of polarizers. The first kind presents an anisotropic absorption—as in a Polaroid film—and the second one is based on total reflection at the interface with a birefringent medium. Using the Stokes vector representation, we determine explicitly the trajectories of the wave light polarization during the polarization process. We find that such trajectories are not always geodesics of the Poincaré sphere as is usually thought. Using the analogy between light polarization and special relativity, we find that the action of successive polarizers on the light wave polarization is equivalent to the action of a single resulting polarizer followed by a rotation achieved, for example, by a device with optical activity. We find a composition law for polarizers similar to the composition law for noncollinear velocities in special relativity. We define an angle equivalent to the relativistic Wigner angle which can be used to quantify the quality of two composed polarizers.

  7. The Physics of Polarization

    NASA Astrophysics Data System (ADS)

    Degl'Innocenti, Egidio Landi

    2015-10-01

    The introductory lecture that has been delivered at this Symposium is a condensed version of an extended course held by the author at the XII Canary Island Winter School from November 13 to November 21, 2000. The full series of lectures can be found in Landi Degl'Innocenti (2002). The original reference is organized in 20 Sections that are here itemized: 1. Introduction, 2. Description of polarized radiation, 3. Polarization and optical devices: Jones calculus and Muller matrices, 4. The Fresnel equations, 5. Dichroism and anomalous dispersion, 6. Polarization in everyday life, 7. Polarization due to radiating charges, 8. The linear antenna, 9. Thomson scattering, 10. Rayleigh scattering, 11. A digression on Mie scattering, 12. Bremsstrahlung radiation, 13. Cyclotron radiation, 14. Synchrotron radiation, 15. Polarization in spectral lines, 16. Density matrix and atomic polarization, 17. Radiative transfer and statistical equilibrium equations, 18. The amplification condition in polarized radiative transfer, and 19. Coupling radiative transfer and statistical equilibrium equations.

  8. Building Power Between Polarities

    PubMed Central

    Ventres, William B.

    2016-01-01

    In this article, I introduce the concept of the space-in-between. This space-in-between is born of the realization that, between the expression of any two polarities (across dimensions such as emotion, thought, geography, and ideology), there exists a philosophical construct useful for framing thinking about practice, research, and managerial relationships in the health professions. Out of this construct emerge practical considerations useful for structuring the conduct of meaningful interpersonal and intercultural interactions. I describe how the idea of a space-in-between developed out of my medical practice, grew as a result of my experiences in international environments. and has found fulfillment in my ongoing work. I explore the application of a space-in-between in public health, medical anthropology, medical ethics, and global health. I review how, as a result of incorporating this space in their daily work, clinicians, educators, researchers, and managers can grow as leaders by sharing the presence that arises from the space-in-between them and the people in the communities they serve. PMID:26531880

  9. Transport of polar winter lower-thermospheric Nitric Oxide to the Stratosphere

    NASA Astrophysics Data System (ADS)

    Bailey, S. M.; Thurairajah, B.; Randall, C. E.; Siskind, D. E.; Hervig, M. E.; Russell, J. M.

    2013-12-01

    Nitric oxide (NO) is a key minor constituent of the lower thermosphere. It is produced there via processes that are initiated with the ionization of N2. This ionization occurs by solar soft X-ray irradiance globally and by precipitating energetic particles in the polar regions. In the mesosphere and stratosphere NO participates in an important catalytic reaction which results in the destruction of ozone. Evidence of NO transported in the Northern Hemisphere (NH) winter from the lower thermosphere to the stratosphere has been growing in recent years. In particular, Stratospheric Sudden Warmings (SSWs) have been identified as triggers of enhanced NO descent. In this talk, we discuss observations of NO from the Solar Occultation for Ice Experiment (SOFIE) instrument on-board the Aeronomy of Ice in the Mesosphere (AIM) satellite. Six years of polar NO observations from 40 to 140 km are now available, including the NH winters of 2007-2008 through 2012-2013. SOFIE shows dramatic transport of NO in the NH winters of both 2008-2009 and 2012-2013. Both of these episodes occur after major SSWs. A weaker but very large enhancement of NO was observed in 2012 after a minor SSW. In each case, SOFIE observations of water also show evidence of transport and SOFIE observations of temperature show an elevated stratopause. These results are consistent with previous observations and the inferred role of SSWs. We will show the SOFIE observations and explore how the strength and timing of SSWs control the magnitude of the NO transport.

  10. Dietary intakes of choline: What We Eat In America, NHANES 2007-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this report is to present data on the choline intake of the U.S. population and the food categories that contribute to intake. The dietary data was from twenty-four hour recall provided by all 9,118 individuals who participated in What We Eat In America, NHANES 2007–2008. The analys...

  11. North Dakota University System Summary of 2007-2008 Annual Budgets

    ERIC Educational Resources Information Center

    North Dakota University System, 2007

    2007-01-01

    The 2007-08 operating budget for the North Dakota University System is over $960 million. Approximately 28 percent of operations are supported by the state general fund. The remainder of the operations of the University System are self-supporting through tuition and fees, room and board charges paid by students, and private and federal research…

  12. Low-fat Milk Consumption among Children and Adolescents in the United States, 2007-2008

    MedlinePlus

    ... from the National Technical Information Service NCHS Low-fat Milk Consumption Among Children and Adolescents in the ... results not shown). What type of milk, by fat content, do children and adolescents consume? Among children ...

  13. Canada-USA Salmon Shelf Survival Study, 2007-2008 Annual Report.

    SciTech Connect

    Trudel, Marc; Tucker, Strahan; Morris, John

    2009-03-09

    Historically, salmon stocks from the Columbia River and Snake River formed one of the most valuable fisheries on the west coast of North America. However, salmon and steelhead returns sharply declined during the 1980s and 1990s to reach nearly 1 million fish. Although several factors may be responsible for the decline of Columbia River salmon and steelhead, there is increasing evidence that these drastic declines were primarily attributable to persistently unfavorable ocean conditions. Hence, an understanding of the effects of ocean conditions on salmon production is required to forecast the return of salmon to the Columbia River basin and to assess the efficacy of mitigation measures such as flow regulation on salmon resources in this system. The Canadian Program on High Seas Salmon has been collecting juvenile salmon and oceanographic data off the west coast of British Columbia and Southeast Alaska since 1998 to assess the effects of ocean conditions on the distribution, migration, growth, and survival of Pacific salmon. Here, we present a summary of the work conducted as part of the Canada-USA Salmon Shelf Survival Study during the 2008 fiscal year and compare these results with those obtained from previous years. The working hypothesis of this research is that fast growth enhances the marine survival of salmon, either because fast growing fish quickly reach a size that is sufficient to successfully avoid predators, or because they accumulate enough energy reserves to better survive their first winter at sea, a period generally considered critical in the life cycle of salmon. Sea surface temperature decreased from FY05 to FY08, whereas, the summer biomass of phytoplankton increased steadily off the west coast of Vancouver Island from FY05 to FY08. As in FY07, zooplankton biomass was generally above average off the west coast of Vancouver Island in FY08. Interestingly, phytoplankton and zooplankton biomass were higher in FY08 than was expected from the observed nutrient concentration that year. This suggests nutrients were more effectively by phytoplankton in FY08. In addition, the abundance of lipid-rich northern copepods increased from FY05 to FY08, whereas lipid-poor southern copepods showed the opposite pattern, suggesting that growth conditions were more favorable to juvenile salmon in FY08 than in previous years. However, growth indices for juvenile coho salmon were near the 1998-2008 average, both off the west coast of Vancouver Island and Southeast Alaska, indicating that additional factors beside prey quality affect juvenile salmon growth in the marine environment. Catches of juvenile Chinook, sockeye and chum salmon off the west coast of Vancouver Island in June-July 2008 were the highest on record during summer since 1998, suggesting that early marine survival for the 2008 smolt year was high. Interestingly, the proportion of hatchery fish was high (80-100%) among the juvenile Columbia River Chinook salmon caught off the British Columbia coast during summer, suggest that relatively few wild Chinook salmon are produced in the Columbia River Chinook. In addition, we also recovered two coded-wire tagged juvenile Redfish Lake sockeye salmon in June 2008 off the west coast of British Columbia. As relatively few Redfish Lake sockeye smolts are tagged each year, this also suggests that early marine survival was high for these fish, and may result in a high return in 2009 if they mature at age three, or in 2010 if they mature at age four. To date, our research shows that different populations of Columbia River salmon move to different locations along the coastal zone where they establish their ocean feeding grounds and overwinter. We further show that ocean conditions experienced by juvenile Columbia River salmon vary among regions of the coast, with higher plankton productivity and temperatures off the west coast of Vancouver Island than in Southeast Alaska. Hence, different stocks of juvenile salmon originating from the Columbia River and Snake River are exposed to different ocean conditions and may respond differently to climate changes. In particular, our work shows that the growth and fat content of Chinook and coho salmon vary along different parts of the coast and among years. These growth differences appear to be associated with differences in prey quality rather than by a direct effect of temperature on salmon growth or prey quantity, indicating that changes in ocean conditions and circulation affect salmon production indirectly through changes in prey community composition and quality. Taken together, our analyses indicate that the relative survival of different stocks of salmon in the ocean will depend on where they migrate in the ocean, and that changes at the base of the food chain must be taken into consideration to understand the effects of ocean conditions on salmon growth, and hence, on salmon survival.

  14. Connecticut Women's Education and Legal Fund Annual Report, 2007-2008

    ERIC Educational Resources Information Center

    Connecticut Women's Education and Legal Fund, 2008

    2008-01-01

    Connecticut Women's Education and Legal Fund (CWEALF) is a statewide non-profit organization dedicated to empowering women, girls and their families to achieve equal opportunities in their personal and professional lives. Members are guided by their commitment to feminism, diversity, empowerment, personal responsibility and self-sufficiency,…

  15. Kootenai River Floodplain Ecosystem Operational Loss Assessment, Protection, Mitigation and Rehabilitation, 2007-2008 Annual Report.

    SciTech Connect

    Merz, Norm

    2009-02-18

    The overarching goals of the 'Kootenai River Floodplain Ecosystem Operational Loss Assessment, Protection, Mitigation and Rehabilitation' Project (BPA Project No.2002-011-00) are to: (1) assess abiotic and biotic factors (i.e., geomorphologic, hydrological, aquatic and riparian/floodplain communities) in determining a definitive composition of ecological integrity, (2) develop strategies to assess and mitigate losses of ecosystem functions, and (3) produce a regional operational loss assessment framework. To produce a scientifically defensible, repeatable, and complete assessment tool, KTOI assembled a team of top scientists in the fields of hydrology, hydraulics, ornithology, entomology, statistics, and river ecology, among other expertise. This advisory team is known as the Research Design and Review Team (RDRT). The RDRT scientists drive the review, selection, and adaptive management of the research designs to evaluate the ecologic functions lost due to the operation of federal hydropower facilities. The unique nature of this project (scientific team, newest/best science, adaptive management, assessment of ecological functions, etc.) has been to work in a dynamic RDRT process. In addition to being multidisciplinary, this model KTOI project provides a stark contrast to the sometimes inflexible process (review, re-review, budgets, etc.) of the Columbia River Basin Fish and Wildlife Program. The project RDRT is assembled annually, with subgroups meeting as needed throughout the year to address project issues, analyses, review, and interpretation. Activities of RDRT coordinated and directed the selection of research and assessment methodologies appropriate for the Kootenai River Watershed and potential for regional application in the Columbia River Basin. The entire RDRT continues to meet annually to update and discuss project progress. RDRT Subcontractors work in smaller groups throughout the year to meet project objectives. Determining the extent to which ecological systems are experiencing anthropogenic disturbance and change in structure and function is critical for long term conservation of biotic diversity in the face of changing landscapes and land use. KTOI and the RDRT propose a concept based on incorporating hydrologic, aquatic, and terrestrial components into an operations-based assessment framework to assess ecological losses as shown in Figure E-1.

  16. 78 FR 50113 - Distribution of 2004, 2005, 2006, 2007, 2008, and 2009 Cable Royalty Funds

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-16

    ... September 16, 2013. ADDRESSES: Participants must submit an original, five paper copies, and an electronic..., music, etc.). For broadcast years 2006 through 2009, the parties settled their controversies. The...

  17. Bluetongue disease in Germany (2007-2008): monitoring of entomological aspects.

    PubMed

    Mehlhorn, Heinz; Walldorf, Volker; Klimpel, Sven; Schaub, Günter; Kiel, Ellen; Focke, René; Liebisch, Gabriele; Liebisch, Arndt; Werner, Doreen; Bauer, Christian; Clausen, Henning; Bauer, Burkhard; Geier, Martin; Hörbrand, Thomas; Bätza, Hans-Joachim; Conraths, Franz J; Hoffmann, Bernd; Beer, Martin

    2009-08-01

    In the summer of 2006, a bluetongue epidemic started in the border area of Belgium, The Netherlands, and Germany, spread within 2 years over large areas of Western and Central Europe, and caused substantial losses in farm ruminants. Especially sheep and cattle were severely affected, leading to a case-fatality ratio of nearly 40% in sheep (Conraths et al., Emerg Inf Dis 15(3):433-435, 2009). The German federal ministry of food, agriculture, and consumer protection (BMELV) established a countrywide monitoring on the occurrence of the vectors of this virus, i.e., midges (family Ceratopogonidae) of the genus Culicoides. The monitoring was done on 91 sites, most of which were localized in the 150-km restriction zone that existed in December 2006. A grid consisting of 45 x 45 km(2) cells was formed that covered the monitoring area. As a rule, one trap was placed into each grid cell. The monitoring program started at the end of March 2007 and lasted until May 2008. It included the catching of midges by ultraviolet light traps-done each month from days 1 until 8, the selection of midges of the Culicoides obsoletus, Culicoides pulicaris group, and other Culicoides spp., the testing of midges for bluetongue virus (BTV) by polymerase chain reaction (PCR), and the daily registration of weather data at each trap site for the whole monitoring period. The following main results were obtained: (1) Members of the C. obsoletus group were most commonly found in the traps, reaching often 3/4 of the catches. The African and South European vector of BTV-the species Culicoides imicola-was never found. (2) Members of the C. obsoletus group were most frequently found infected with BTV besides a few cases in the C. pulicaris group and other species. (3) Members of the C. obsoletus group were also found in winter. Their numbers were reduced, however, and they were caught mostly close to stables. Therefore, a true midge-free period does not exist during the year in Germany. (4) The amounts of midges caught daily depended on the weather conditions. If it was cold and/or windy, the traps contained only a few specimens. Since the months from January to May 2008 were considerably colder (at all farms) than their correspondents in 2007, the growing of the population of midges started 2-3 months later in 2008 than in 2007. (5) The highest populations of midges occurred in both years (2007 and 2008) during the months September and October. This corresponded significantly to the finding of highest numbers of infected midges and to the number of diseased cattle and sheep during these 2 months. (6) It is noteworthy that in general, the first virus-positive midges of the species C. obsoletus were found about 1 1/2 months later than the first clinical cases had occurred or later than the first PCR-proven virus-positive sentinel animals had been documented. In 2007, the first BTV-positive cattle were detected in May in North Rhine-Westphalia, while the first positive Culicoides specimens were only found in August on the same farm. Evaluating these main results of the entomological monitoring and the fact that many wild ruminants have also been infected with BTV, it becomes evident that bluetongue disease has become endemic in Central Europe, and that only constant effort including vaccination and perhaps also insecticidal protection of cattle and sheep will keep the economical losses at a reasonable level. The following papers (1-10) in this journal will contribute more details obtained from this worldwide unique entomological monitoring: Bartsch et al. 2009; Bauer et al. 2009; Stephan et al. 2009; Clausen et al. 2009; Hörbrand and Geier 2009; Kiehl et al. 2009; Mehlhorn et al. 2009; Kiel et al. 2009; Vorsprach et al. 2009; Balczun et al. 2009. PMID:19322587

  18. Analysis of enterovirus and adenovirus presence in swimming pools in Cyprus from 2007-2008.

    PubMed

    Bashiardes, S; Koptides, D; Pavlidou, S; Richter, J; Stavrou, N; Kourtis, C; Papageorgiou, G T; Christodoulou, C G

    2011-01-01

    An analysis was carried out to determine the presence of enteroviruses and adenoviruses in public swimming pools in Cyprus. The effectiveness of the commonly implemented disinfection procedure of chlorination was confirmed by determination of bacteriological markers. Analysis of viral presence was carried out by sampling random swimming pools from the five major cities in Cyprus during a period of 21 months spanning from April 2007 to December 2008. A 10 I sample was taken from each swimming pool to be tested and was subsequently concentrated via membrane filtration using a new methodological approach for virus elution. Concentrated samples were analysed using of a Real Time Polymerase Chain Reaction (PCR) TaqMan probe based approach to detect the presence of enteroviruses and adenoviruses. Over the period of 21 months a total of 126 swimming pools were sampled and analysed. In four swimming pools enteroviruses were detected, in one pool echovirus 18 was identified, in two pools echovirus 30 was identified and in one other pool poliovirus Sabin 1 was identified. Similarly, in four swimming pools adenoviruses were detected, in all four adenovirus 41 was identified. Bacteriological marker analysis showed that 98% of pools complied with Cyprus regulations. PMID:22049764

  19. Serological status of Canadian cattle for brucellosis, anaplasmosis, and bluetongue in 2007-2008.

    PubMed

    Paré, Julie; Geale, Dorothy W; Koller-Jones, Maria; Hooper-McGrevy, Kathleen; Golsteyn-Thomas, Elizabeth J; Power, Christine A

    2012-09-01

    A national bovine serological survey was conducted to confirm that the prevalence of brucellosis, bluetongue, and anaplasmosis does not exceed 0.02% (95% confidence) in live cattle in Canada. Sampling consisted of a systematic random sample of 15 482 adult cattle slaughtered in federally inspected abattoirs, stratified by province. Samples were tested to detect antibodies for brucellosis, bluetongue, and anaplasmosis. All samples were negative for brucellosis. Three samples were seroreactors to bluetongue, 2 of which originated from the Okanagan Valley in British Columbia and 1 from Ontario, which after follow-up, was considered an atypical result. A total of 244 samples were seroreactors to Anaplasma and follow-up identified infection in Saskatchewan, Manitoba, and Quebec. In conclusion, the Canadian cattle population remains free of brucellosis and free of bluetongue outside the Okanagan Valley. Canada is no longer free of anaplasmosis and will be unable to claim freedom until eradication measures are completed. PMID:23450858

  20. Surveillance of air-travel-related tuberculosis incidents, England and Wales: 2007-2008.

    PubMed

    Abubakar, I; Welfare, R; Moore, J; Watson, J M

    2008-06-01

    The potential spread of tuberculosis (TB) from infectious passengers during air travel has recently received increasing attention in the media and from public health authorities. We reviewed all air travel-related tuberculosis incidents reported to the Health Protection Agency Centre for Infections between January 2007 and February 2008 in England and Wales and investigated the effectiveness of contact investigation. Incidents involving air travel were defined according to the World Health Organization's guidelines on TB and Air Travel. We collected data on the index case, the incident and the outcome of contact investigation where available. We identified 24 incidents involving 39 flights. The median flight duration was 8.9 hours (inter-quartile range (IQR) 8 to 11.7). Most flights (36) were from or to a high burden country and 19 of the 24 incidents reported had a smear-positive index case. Two index cases had multidrug-resistant tuberculosis. In 17 incidents, no further investigation could be undertaken due to the lack of passenger information. In the remaining seven incidents, the quality of contact information obtained was variable. No further cases of TB infection or disease were identified. This study suggests that the process of investigating passenger contacts of a TB infected individual travelling by air is complicated and usually unsuccessful without dedicated resources and availability of high-quality contact information from airlines. Further research into the effectiveness of contact investigation in this setting is needed. PMID:18761951

  1. Los Angeles County Juvenile Justice Crime Prevention Act: Fiscal Year 2007-2008 Report. Technical Report

    ERIC Educational Resources Information Center

    Fain, Terry; Turner, Susan; Ridgeway, Greg

    2010-01-01

    In 2000, the California State Legislature passed the Schiff-Cardenas Crime Prevention Act, which authorized funding for county juvenile-justice programs and designated the Corrections Standards Authority (CSA) (formerly named the Board of Corrections) the administrator of funding. A 2001 California Senate bill extended the funding and changed the…

  2. Research in Our Schools: Duke University School Research Partnership Office, Research Studies 2007-2008

    ERIC Educational Resources Information Center

    Center for Child and Family Policy, Duke University (NJ1), 2008

    2008-01-01

    The Duke University School Research Partnership (SRP) Office was developed with support from the Office of the Provost and the Center for Child and Family Policy. Begun in 2006 as the Duke Office for Research in Schools (DORIS), the SRP Office is an integral part of the work of the Center for Child and Family Policy. The SRP Office facilitates…

  3. Snacking patterns of U.S. adults: What We Eat In America, 2007-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The goals of this study were to track changes in snacking frequency over time, determine whether snacking is associated with food energy intake and weight status, identify foods and beverages that make the largest contributions to calories consumed at snacks, and measure the contribution of snacks t...

  4. The Afterschool Experience in "Salsa, Sabor y Salud": Evaluation, 2007-2008. CRESST Report 747

    ERIC Educational Resources Information Center

    Huang, Denise; La Torre, Deborah; Oh, Christine; Harven, Aletha; Huber, Lindsay; Leon, Seth; Mostafavi, Sima

    2008-01-01

    In the United States, there is an alarming trend toward obesity and inactivity among children. Minorities and economically disadvantaged children are at an even higher risk. According to the Centers for Disease Control and Prevention one in two Latino children will become diabetic. As a result, there is a dire need for tailored intervention…

  5. Detecting early signs of the 2007-2008 crisis in the world trade.

    PubMed

    Saracco, Fabio; Di Clemente, Riccardo; Gabrielli, Andrea; Squartini, Tiziano

    2016-01-01

    Since 2007, several contributions have tried to identify early-warning signals of the financial crisis. However, the vast majority of analyses has focused on financial systems and little theoretical work has been done on the economic counterpart. In the present paper we fill this gap and employ the theoretical tools of network theory to shed light on the response of world trade to the financial crisis of 2007 and the economic recession of 2008-2009. We have explored the evolution of the bipartite World Trade Web (WTW) across the years 1995-2010, monitoring the behavior of the system both before and after 2007. Our analysis shows early structural changes in the WTW topology: since 2003, the WTW becomes increasingly compatible with the picture of a network where correlations between countries and products are progressively lost. Moreover, the WTW structural modification can be considered as concluded in 2010, after a seemingly stationary phase of three years. We have also refined our analysis by considering specific subsets of countries and products: the most statistically significant early-warning signals are provided by the most volatile macrosectors, especially when measured on developing countries, suggesting the emerging economies as being the most sensitive ones to the global economic cycles. PMID:27461469

  6. Monitoring of Bright Blazars with MAGIC in the 2007/2008 Season

    SciTech Connect

    Satalecka, Konstancja; Bernardini, Elisa; Majumdar, Pratik; Hsu, Ching-Cheng; Galante, Nicola; Goebel, Florian; Wagner, Robert; Bonnoli, Giacomo; Stamerra, Antonio; Lindfors, Elina

    2009-04-08

    Because of the short duty-cycles and observation-time constraints, studies of bright TeV (E>100 GeV) blazars are mostly restricted to flaring episodes or rather short (days to few weeks) multiwavelength campaigns. At the same time, long-term studies of these objects are essential to gain a more complete understanding of the blazar phenomenon and to constrain theoretical models concerning jet physics. Only unbiased long-term studies are adequate for the determination of flaring state probabilities and for estimating the statistical significance of possible correlations between TeV flaring states and other wavebands or observables, such as neutrino events. Regular observations also provide triggers for multiwavelength ToO observations originating from the TeV waveband. These are particularly needed to identify and study orphan TeV flares, i.e. flares without counterparts in other wavebands. In 2007/8 the MAGIC telescope has monitored three TeV blazars on a regular basis: Mrk 501, Mrk 421, and 1ES 1959+650. We present preliminary results of these observations including the measured light curves and a correlation study for VHE {gamma}-rays and X-rays and VHE {gamma}-rays and optical R-band for Mrk 421.

  7. State Data Exchange: "39 Years and Still Counting." 2007-2008 Highlights

    ERIC Educational Resources Information Center

    Southern Regional Education Board (SREB), 2009

    2009-01-01

    The SREB-State Data Exchange is a cooperative effort of SREB and the statewide higher education governing and coordinating boards in the South. Founded in 1969-1970, it is one of the nation's oldest, most comprehensive sources of comparative data on public higher education. The Data Exchange annually collects, compiles and publishes the most…

  8. Test Coordinator's Guide for Federal and State Assessments, 2007-2008

    ERIC Educational Resources Information Center

    Idaho State Department of Education, 2007

    2007-01-01

    This guide for testing coordinators includes information regarding: (1) Idaho statewide testing (both state and federal requirements); (2) testing dates; (3) Idaho Reading indicator (IRI); (4) Direct Mathematics Assessment (DMA); (5) Direct Writing Assessment (DEA); (6) Idaho Alternative Assessment (IAA); (7) Idaho Standards Achievement Test…

  9. Vital Signs: Food categories contributing the most to sodium consumption - United States, 2007-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most of the U.S. population consumes sodium in excess of daily guidelines (<2,300 mg overall and 1,500 mg for specific populations). Excessive sodium consumption raises blood pressure, which is a major risk factor for heart disease and stroke, the nation’s first and fourth leading causes of death. I...

  10. Turning points in nonlinear business cycle theories, financial crisis and the 2007-2008 downturn.

    PubMed

    Dore, Mohammed H I; Singh, Ragiv G

    2009-10-01

    This paper reviews three nonlinear dynamical business cycle theories of which only one (The Goodwin model) reflects the stylized facts of observed business cycles and has a plausible turning point mechanism. The paper then examines the US (and now global) financial crisis of 2008 and the accompanying downturn in the US. The paper argues that a skewed income distribution could not sustain effective demand and that over the 2001-2006 expansion demand was maintained through massive amounts of credit, with more than 50 percent of sales in the US being maintained through credit. A vector autoregression model confirms the crucial role played by credit. However legislative changes that dismantled the restrictions placed on the financial sector after the crash of 1929 and the consequent structural changes in the financial sector after 1980 enabled the growth of new debt instruments and credit. But overexpansion of credit when profits and house prices were declining in 2005/06 led to a nonlinear shift due to a new realization of the poor quality of some of this debt, namely mortgage backed securities. Bankruptcies, followed by retrenchment at the banks, then led to the bursting of the credit bubble, with the possibility of a severe recession. PMID:19781138

  11. Council on Library and Information Resources: Annual Report, 2007-2008

    ERIC Educational Resources Information Center

    Council on Library and Information Resources, 2008

    2008-01-01

    This annual report of the Council on Library and Information Resources (CLIR) contains an overview of activities of the Council between July 1, 2007 and June 30, 2008. These include programs, advisory groups, grants and contracts, and financial statements. It also includes a list of staff, a letter from the chairperson Paula Kaufman, and a message…

  12. The Use of Restrictive Interventions in Victoria, Australia: Population Data for 2007-2008

    ERIC Educational Resources Information Center

    Webber, Lynne S.; McVilly, Keith R.; Stevenson, Elaine; Chan, Jeffrey

    2010-01-01

    The once common use of restrictive interventions (the use of restraint and seclusion) for controlling the behaviour of people with an intellectual disability is now coming under greater scrutiny by government and community sector services. Questions are being raised with respect to the clinical efficacy and ethical appropriateness of such…

  13. Protect and Restore Red River Watershed, 2007-2008 Annual Report.

    SciTech Connect

    Bransford, Stephanie

    2009-05-04

    The Nez Perce Tribe Department of Fisheries Resource Management, Watershed Division approaches watershed restoration with a ridge-top to ridge-top approach. The Nez Perce Tribe (NPT) and the Nez Perce National Forest (NPNF) have formed a partnership in completing watershed restoration activities, and through this partnership more work is accomplished by sharing funding and resources in our effort. The Nez Perce Tribe began watershed restoration projects within the Red River Watershed of the South Fork Clearwater River in 2001. Progress has been made in restoring the watershed through road decommissioning and culvert replacement. From completing a watershed assessment to two NEPA efforts and a final stream restoration design, we will begin the effort of restoring the mainstem channel of Red River to provide spawning and rearing habitat for anadromous and resident fish species. Roads have been surveyed and prioritized for removal or improvement as well as culverts being prioritized for replacement to accommodate fish passage throughout the watershed. Another major, and extremely, important component of this project is the Red River Meadow Conservation Easement. We have begun the process of pursuing a conservation easement on approximately 270 acres of prime meadow habitat (Red River runs through this meadow and is prime spawning and rearing habitat).

  14. New Mexico Statewide Assessment Program (NMSAP) Procedures Manual, 2007-2008

    ERIC Educational Resources Information Center

    New Mexico Public Education Department, 2007

    2007-01-01

    This manual has been prepared for all New Mexico Statewide Assessment Program (NMSAP) assessment administrators, teachers, school specialists, and principals. It includes information about the following topics: PED contacts, New Mexico Standards Based Assessments (SBA), Grades 3-8 and 11; New Mexico High School Competency Examination (NMHSCE);…

  15. Surveillance for Waterborne Disease Outbreaks Associated with Drinking Water United States, 2007-2008

    EPA Science Inventory

    Problem/Condition: Since 1971, the Centers for Disease Control and Prevention (CDC), the U.S. Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists have maintained a collaborative Waterborne Disease and Outbreak Surveillance System (WBDOS...

  16. Grande Ronde Subbasin Gauging Station Operations, 2007-2008 Reporting Period.

    SciTech Connect

    Menton, R. Coby

    2008-11-10

    The Grande Ronde Basin (GRB) in Northeast Oregon is a moderately dry climate receiving between 10 and 20 inches of precipitation per year with surrounding mountains accumulating up to 100 inches. Irrigated agriculture is a major part of the economy with water being diverted or pumped from surface and ground sources from April through October. Several ESA listed species exist in the basin including Chinook, steelhead, and bulltrout. Agriculture and ESA (Endangered Species Act) listed aquatic species combined with a dry climate demonstrate the need for a network of stream gauges. The GRB covers over 5,000 square miles and includes several thousand miles of perennial flowing streams. This project is in place to operate 12 existing stream gauges in combination with USGS (4 gauges) and OWRD (one gauge) who, independent of this project, operate five additional gauges (Grande Ronde at Troy, Imnaha R. at Imnaha, Minam R. at Minam, Lookingglass Creek, and Upper Catherine Cr.) to characterizes flow in both the Grande Ronde and Imnaha subbasins. These gauges are intended to assist in irrigation water management, fisheries management, long term flow and trend analysis, TMDL and SB1010 water quality management plan effectiveness, subbasin plan implementation, and provide essential information regarding cumulative effects response to conservation in the GRB. Headwater characteristics, land management influence, and basin outlet data are all selectively collected in this network of 17 flow gauges. Prior to the 2007 water year there were three separate stream gauging programs with similar objectives, protocol, and funding sources in the GRB. Each of these programs for the past ten years has operated under separate administration consuming more time and administrative money than is necessary to accomplish stated objectives. By combining all programs into one project costs have been reduced, each funding source has one contract instead of three, and the same amount of work has been done accomplishing the same objectives. This objective has been continued and realized in the 2008 water year.

  17. Connecting Worlds/Mundos Unidos Project: End-of-Year Report, 2007-2008

    ERIC Educational Resources Information Center

    Ciriza, Frank

    2008-01-01

    This report presents information on the Connecting Worlds/Mundos Unidos Project and provides a general comparison overview of accomplishments during its five years of operation. The Connecting Worlds/Mundos Unidos Project has been operating in the El Paso Independent School District (EPISD) for eleven years, but in the present format as a Jacob K.…

  18. Emergence of fluoroquinolone-resistant Neisseria meningitidis--Minnesota and North Dakota, 2007-2008.

    PubMed

    2008-02-22

    Meningoccocal disease causes substantial morbidity and mortality; approximately 10% of cases are fatal. Among those who survive, 10%-15% have long-term sequelae. Nasopharyngeal carriage of Neisseria meningitidis is a precursor to disease; however, the majority of carriers do not develop disease. Household and other close contacts of persons with meningococcal disease have a higher risk for carriage and therefore invasive disease. These persons should receive antibiotic chemoprophylaxis to eliminate nasopharyngeal carriage of N. meningitidis as soon as possible. The rate of secondary disease for close contacts is highest immediately after onset of disease in the index patient; secondary cases rarely occur after 14 days. Ciprofloxacin, a second-generation fluoroquinolone, is an effective single-dose oral chemoprophylaxis agent. Although isolated cases of ciprofloxacin-resistant meningoccocal disease have been described in Argentina, Australia, China, France, India, and Spain, resistance has not been reported in North America. This report describes a cluster of three cases of fluoroquinolone-resistant meningococcal disease that occurred among residents of the border area of North Dakota and Minnesota during January 2007-January 2008. The first of these cases was epidemiologically linked and had closely related molecular features to a 2006 case of fluoroquinolone-susceptible meningococcal disease that occurred in the same geographic region. Until further notice, ciprofloxacin should not be used for chemoprophylaxis of close contacts of persons with meningococcal disease in selected counties in North Dakota and Minnesota. Ceftriaxone, rifampin, and azithromycin are alternative agents. PMID:18288075

  19. 2007-2008 Annual Progress Report for BPA Grant Exp Restore Walla Walla River Flow

    SciTech Connect

    Bower, Bob

    2009-07-10

    WWBWC and its partners have been working on a wide variety of conservation and aquifer recharge related activities including: monitoring groundwater and surface water conditions, creating a geospatial database for the Walla Walla River valley (project focal area), expanding aquifer recharge testing at the HBDIC site and conducting an extensive outreach/education program by which to share the information, ideas and potential solutions to our current water management issues in this basin. This report is an outline of those activities and is accompanied by individual program-component (attached as appendices) reports for the areas that BPA is assisting to fund these on-the-ground projects along with the innovative research and monitoring being done to further aquifer recharge as a water management tool for the Pacific Northwest.

  20. Kootenai River Fisheries Investigations: Salmonid Studies Project Progress Report, 2007-2008 Annual Report.

    SciTech Connect

    Paragamian, Vaughn L.; Walters, Jody; Maiolie, Melo

    2009-04-09

    This research report addresses bull trout Salvelinus confluentus and Redband trout Oncorhynchus mykiss redd surveys, population monitoring, trout distribution, and abundance surveys in the Kootenai River drainage of Idaho. The bull trout is one of several sport fish native to the Kootenai River, Idaho that no longer supports a fishery. Because bull trout are listed under the Endangered Species Act, population data will be vital to monitoring status relative to recovery goals. Thirty-three bull trout redds were found in North and South Callahan creeks and Boulder Creek in 2007. This is a decrease from 2006 and 2005 and less than the high count in 2003. However, because redd numbers have only been monitored since 2002, the data series is too short to determine bull trout population trends based on redd counts. Redband trout still provide an important Kootenai River sport fishery, but densities are low, at least partly due to limited recruitment. The redband trout proportional stock density (PSD) in 2007 increased from 2006 for a second year after a two-year decline in 2004 and 2005. This may indicate increased recruitment to or survival in the 201-305 mm length group due to the minimum 406 mm (16 inches) length limit initiated in 2002. We conducted 13 redd surveys and counted 44 redband trout redds from May 7 to June 3, 2007 in a 3.8 km survey reach on Twentymile Creek. We surveyed streams in the Kootenai River valley to look for barriers to trout migration. Man-made barriers, for at least part of the year, were found on Caboose, Debt, Fisher, and Twenty Mile creeks. Removing these barriers would increase spawning and rearing habitat for trout and help to restore trout fisheries in the Kootenai River.

  1. Beverage choices of U.S. adults: What We Eat In America, NHANES 2007-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The goals of this study were to describe beverage consumption patterns of the U.S. adult population, determine whether beverage choices differ by gender, age, and race/ethnicity, and examine the impact of beverages on total daily nutrient intakes. Twenty-four hour dietary recall data from 5,334 adu...

  2. 2007-2008 What We Eat In America, NHANES Tables 37-40

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The widespread use of dietary supplements can contribute substantially to nutrient intakes; however, collection methods for dietary supplements and food intakes have limited the ability to estimate total nutrient intakes for the U.S. population. As of 2007, supplement usage was collected as part of...

  3. MCPS School Safety and Security at a Glance 2007-2008

    ERIC Educational Resources Information Center

    Montgomery County Public Schools, 2008

    2008-01-01

    "MCPS School Safety and Security at a Glance" provides, in a single document, information about the reporting of incidents related to school safety and security, including school climate, local school safety program descriptions, and serious incidents in all Montgomery County (Maryland) Public Schools. The information is presented for…

  4. Duck Valley Reservoirs Fish Stocking and O&M, Annual Progress Report 2007-2008.

    SciTech Connect

    Sellman, Jake; Perugini, Carol

    2009-02-20

    The Duck Valley Reservoirs Fish Stocking and Operations and Maintenance Project (DV Fisheries) is an ongoing resident fish program that serves to partially mitigate the loss of anadromous fish that resulted from downstream construction of the federal hydropower system. The project's goals are to enhance subsistence fishing and educational opportunities for Tribal members of the Shoshone-Paiute Tribes and provide fishing opportunities for non-Tribal members. In addition to stocking rainbow trout (Oncorhynchus mykiss) in Mountain View (MVR), Lake Billy Shaw (LBS), and Sheep Creek Reservoirs (SCR), the program is also designed to: maintain healthy aquatic conditions for fish growth and survival, provide superior facilities with wilderness qualities to attract non-Tribal angler use, and offer clear, consistent communication with the Tribal community about this project as well as outreach and education within the region and the local community. Tasks for this performance period fall into three categories: operations and maintenance, monitoring and evaluation, and public outreach. Operation and maintenance of the three reservoirs include maintaining fences, roads, dams and all reservoir structures, feeder canals, water troughs, stock ponds, educational signs, vehicles, equipment, and restroom facilities. Monitoring and evaluation activities include creel, gillnet, wildlife, and bird surveys, water quality and reservoir structures monitoring, native vegetation planting, photo point documentation, and control of encroaching exotic vegetation. Public outreach activities include providing environmental education to school children, providing fishing reports to local newspapers and vendors, updating the website, hosting community environmental events, and fielding numerous phone calls from anglers. The reservoir monitoring program focuses on water quality and fishery success. Sheep Creek Reservoir and Lake Billy Shaw had less than productive trout growth due to water quality issues including dissolved oxygen and/or turbidity. Regardless, angler fishing experience was the highest at Lake Billy Shaw. Trout in Mountain View Reservoir were in the best condition of the three reservoirs and anglers reported very good fishing there. Water quality (specifically dissolved oxygen and temperature) remain the main limiting factors in the fisheries, particularly in late August to early September.

  5. International Heliophysical Year

    NASA Technical Reports Server (NTRS)

    Davila, J. M.; Harrison, R.; Poland, A.; St.Cyr, O. C.; Thompson, B. J.; Rabin, Douglas (Technical Monitor)

    2002-01-01

    In 1957 a program of international research, inspired by the International Polar Years of 1882-83 and 1932-33, was organized as the International Geophysical Year (IGY) to study global phenomena of the Earth and geospace. The IGY involved about 60,000 scientists from 66 nations, working at thousands of stations, from pole to pole to obtain simultaneous, global observations on Earth and in space. There had never been anything like it before. The fiftieth anniversary of the International Geophysical Year will occur in 2007. We propose to organize an international program of scientific collaboration for this time period called the International Heliophysical Year (IHY). Like it predecessors, the IHY will focus on fundamental global questions of Earth science.

  6. Device For Viewing Polarized Light

    NASA Technical Reports Server (NTRS)

    Noever, David A.

    1995-01-01

    Technique for detection of polarized light based on observation of scene through two stacked polarizing disks. No need to rotate polarizers to create flicker indicative of polarization. Implemented by relatively simple, lightweight apparatus. Polarization seen as bow-tie rainbow pattern. Advantageous for detecting polarization in variety of meteorological, geological, astronomical, and related applications.

  7. Study of polarization effects at Nuclotron

    NASA Astrophysics Data System (ADS)

    Ladygin, V. P.; Janek, M.; Kurilkin, P. K.; Ladygina, N. B.; Batyuk, P. N.; Mertz, S. P.

    2016-02-01

    The major goal of the upgraded Nuclotron facility is to obtain the information on the equation-of-state for dense nuclear matter playing a key role in the under standing of the collapse supernovae and neutron stars stability. These studies can be performed either in heavy ion collisions or via the short-range few nucleon correlations. The obtained experimental results and future program with the use of polarized deuteron beam and the internal target station are discussed. The polarization studies for the NN, NA and dA reactions with the extracted deuteron beam at the BM@N setup are proposed. The further extension of the polarization program at BM@N is related with the study of the in-medium modification of the polarization for the strange and multi-strange baryons and the spin alignment for vector mesons decaying in hadronic modes.

  8. Graphene-based magnetless converter of terahertz wave polarization

    NASA Astrophysics Data System (ADS)

    Melnikova, Veronica S.; Polischuk, Olga V.; Popov, Vyacheslav V.

    2016-04-01

    The polarization conversion of terahertz radiation by the periodic array of graphene nanoribbons located at the surface of a high-refractive-index dielectric substrate (terahertz prism) is studied theoretically. Giant polarization conversion at the plasmon resonance frequencies takes place without applying external DC magnetic field. It is shown that the total polarization conversion can be reached at the total internal reflection of THz wave from the periodic array of graphene nanoribbons even at room temperature.

  9. Consecutive polarizers arrangement producing maximum polarized light intensity

    NASA Astrophysics Data System (ADS)

    Wirjawan, Johannes V. D.

    2016-03-01

    Polarizer mainly functions as a specific filter that blocks or transmits lights of certain polarization. Malus' law predicts the average intensity of polarized light passing a polarizer that transmits certain polarization direction will be proportional to the squared cosine of angle between the two polarization directions. Arranging several polarizers consecutively with various transmission directions will produce various final intensity as well as final polarized direction. Specific arrangement of an arbitrary number (N > 3) of polarizers producing maximum intensity of polarized light will be discussed in this paper. In addition, interesting pattern of maximum values of some trigonometric functions that are difficult to be solved analytically can be obtained from this discussion.

  10. Status of NSF's polar programs office raised

    NASA Astrophysics Data System (ADS)

    White, M. Catherine

    Walter Massey, Director of the National Science Foundation, announced on January 13 that he has elevated the status of the Division of Polar Programs (DPP). It is now the Office of Polar Programs and, organizationally, part of the Office of the Director. Effective immediately, the newly created office began reporting to NSF's deputy director. Massey is also reactivating the Board's Committee on Polar Programs to provide NSF with continuing policy guidance and advice.In announcing the program's move, Massey said that NSF's Antarctic and Arctic activities have grown increasingly prominent in recent years as international attention has focused on research programs, environmental concerns, law enforcement, and other issues in both polar regions. “With the increased responsibility we have been given [in the polar regions] comes increased accountability,” Massey said. “I believe that heightening the stewardship for polar programs is an important way to help ensure that we meet the expectations and needs of the polar research communities and others,” he added.

  11. What Colour Is a Polar Bear's Skin?

    ERIC Educational Resources Information Center

    Truchot, Sandrine; Weber, Agathe

    2005-01-01

    The association "Participe Futur", based in France, has set up a fantastic sailing and educational adventure with the help of the International Polar Foundation. A group of scientists left the South of France on 20 March 2005 on a sailing boat named "Alcyon". They will be on board for nine months, travelling all the way from the Mediterranean Sea…

  12. Polarization nulling interferometry for exoplanet detection.

    PubMed

    Spronck, Julien; Pereira, Silvania F; Braat, Joseph J M

    2006-04-01

    We introduce a new concept of nulling interferometer without any achromatic device, using polarization properties of light. This type of interferometer should enable a high rejection ratio in a theoretically unlimited spectral band. We analyze several consequences of the proposed design, notably, the possibility of fast internal modulation. PMID:19516397

  13. Automatic Bayesian polarity determination

    NASA Astrophysics Data System (ADS)

    Pugh, D. J.; White, R. S.; Christie, P. A. F.

    2016-07-01

    The polarity of the first motion of a seismic signal from an earthquake is an important constraint in earthquake source inversion. Microseismic events often have low signal-to-noise ratios, which may lead to difficulties estimating the correct first-motion polarities of the arrivals. This paper describes a probabilistic approach to polarity picking that can be both automated and combined with manual picking. This approach includes a quantitative estimate of the uncertainty of the polarity, improving calculation of the polarity probability density function for source inversion. It is sufficiently fast to be incorporated into an automatic processing workflow. When used in source inversion, the results are consistent with those from manual observations. In some cases, they produce a clearer constraint on the range of high-probability source mechanisms, and are better constrained than source mechanisms determined using a uniform probability of an incorrect polarity pick.

  14. Automatic Bayesian polarity determination

    NASA Astrophysics Data System (ADS)

    Pugh, D. J.; White, R. S.; Christie, P. A. F.

    2016-04-01

    The polarity of the first motion of a seismic signal from an earthquake is an important constraint in earthquake source inversion. Microseismic events often have low signal-to-noise ratios, which may lead to difficulties estimating the correct first-motion polarities of the arrivals. This paper describes a probabilistic approach to polarity picking that can be both automated and combined with manual picking. This approach includes a quantitative estimate of the uncertainty of the polarity, improving calculation of the polarity probability density function for source inversion. It is sufficiently fast to be incorporated into an automatic processing workflow. When used in source inversion, the results are consistent with those from manual observations. In some cases, they produce a clearer constraint on the range of high-probability source mechanims, and are better constrained than source mechanisms determined using a uniform probability of an incorrect polarity pick.

  15. A dual polarized antenna system using a meanderline polarizer

    NASA Technical Reports Server (NTRS)

    Burger, H. A.

    1978-01-01

    Certain applications of synthetic aperture radars require transmitting on one linear polarization and receiving on two orthogonal linear polarizations for adequate characterization of the surface. To meet the current need at minimum cost, it was desirable to use two identical horizontally polarized shaped beam antennas and to change the polarization of one of them by a polarization conversion plate. The plate was realized as a four-layer meanderline polarizer designed to convert horizontal polarization to vertical.

  16. Polarization feedback laser stabilization

    DOEpatents

    Esherick, P.; Owyoung, A.

    1987-09-28

    A system for locking two Nd:YAG laser oscillators includes an optical path for feeding the output of one laser into the other with different polarizations. Elliptical polarization is incorporated into the optical path so that the change in polarization that occurs when the frequencies coincide may be detected to provide a feedback signal to control one laser relative to the other. 4 figs.

  17. International Scientific Unions and Global Research

    NASA Astrophysics Data System (ADS)

    Beer, T.

    2013-05-01

    This presentation will deal with the role that international scientific unions play in coordinating international research efforts. Rather than give a general, theoretical, talk on the role that ICSU - the International Council of Science - plays in International Science, I will briefly outline their role and then focus on a case study relevant to the International Union of Geodesy and Geophysics (IUGG). I will compare the scientific activities, and the outreach and education activities, of two major international research programs - the International Year of Planet Earth and the International Polar Year. These were two of the IGY+50 activities. Past informal polls of conference attendees to determine how many had heard of each IGY+50 event result in. eGY (electronic Geophysical Year) 1% IHY (International Heliophysical Year) 4% IYPE (International Year of Planet Earth) 31% IPY (International Polar Year) 64% Why is IPY the one of which most scientists are aware?

  18. Asymptotes in Polar Coordinates.

    ERIC Educational Resources Information Center

    Fay, Temple H.

    1986-01-01

    An old way to determine asymptotes for curves described in polar coordinates is presented. Practice in solving trigonometric equations, in differentiation, and in calculating limits is involved. (MNS)

  19. Polarization at SLC

    SciTech Connect

    Swartz, M.L.

    1988-07-01

    The SLAC Linear Collider has been designed to readily accommodate polarized electron beams. Considerable effort has been made to implement a polarized source, a spin rotation system, and a system to monitor the beam polarization. Nearly all major components have been fabricated. At the current time, several source and polarimeter components have been installed. The installation and commissioning of the entire system will take place during available machine shutdown periods as the commissioning of SLC progresses. It is expected that a beam polarization of 45% will be achieved with no loss in luminosity. 13 refs., 15 figs.

  20. Polarized negative ions

    SciTech Connect

    Haeberli, W.

    1981-04-01

    This paper presents a survey of methods, commonly in use or under development, to produce beams of polarized negative ions for injection into accelerators. A short summary recalls how the hyperfine interaction is used to obtain nuclear polarization in beams of atoms. Atomic-beam sources for light ions are discussed. If the best presently known techniques are incorporated in all stages of the source, polarized H/sup -/ and D/sup -/ beams in excess of 10 ..mu..A can probably be achieved. Production of polarized ions from fast (keV) beams of polarized atoms is treated separately for atoms in the H(25) excited state (Lamb-Shift source) and atoms in the H(1S) ground state. The negative ion beam from Lamb-Shift sources has reached a plateau just above 1 ..mu..A, but this beam current is adequate for many applications and the somewhat lower beam current is compensated by other desirable characteristics. Sources using fast polarized ground state atoms are in a stage of intense development. The next sections summarize production of polarized heavy ions by the atomic beam method, which is well established, and by optical pumping, which has recently been demonstrated to yield very large nuclear polarization. A short discussion of proposed ion sources for polarized /sup 3/He/sup -/ ions is followed by some concluding remarks.

  1. Polarization In Remote Sensing

    NASA Astrophysics Data System (ADS)

    Egan, Walter G.

    1988-06-01

    Various aspects of polarization in remote sensing are presented including mathematical treatments and selected experimental observations. The observations are of the percent polarization from Haleakala volcanic ash, basalt powder, rhyolytic oumice. rose quartz, niccolite, ilmenite, black oak leaves. dried red pine needles, a New Haven red pine stand, moist soil, the sky above Mauna Loa Observatory, the sky above Long Island in summer and winter, and cirrus clouds. Also, space based shuttle photographic observations of polarization are described. Instrumental polarization from a Cassegrainian telescope is described as well as the design of an imaging soectropolarimeter for remote sensing. A list is presented of twelve polarimetric properties associated with remote sensing.

  2. STRAPOLETE : Studying summer polar stratosphere

    NASA Astrophysics Data System (ADS)

    Payan, Sebastien

    2010-05-01

    The polar stratosphere in the summertime remains largely unexplored. Dynamical conditions are characterized by large scale transport and mixing between air masses of higher and lower latitude origins. Understanding these exchanges is crucial since they have a large impact on the distribution of trace gases and aerosols at polar latitudes, and thus on the stratospheric ozone budget. Ozone change affects the radiative balance, the coupling between troposphere and stratosphere, and therefore the climate. In the framework of the International Polar Year, the STRAPOLETE project starts on January 2009. It is associated with a successful balloon borne campaign which took place close to Kiruna (Sweeden) from 2 August 2009 to 12 September 2009 with eight balloon flights. During this campaign the main characteristics of the summertime arctic stratosphere have been captured. The data set obtained using UV-visible and infrared instruments, remote and in situ sensing embarked spectrometers provided detailed information on vertical distributions of more than fifteen chemical tracers and reactive species from the upper troposphere to the middle stratosphere. A number of in situ optical aerosol counters, a UV-visible remote spectrometer for the aerosol extinction and a photopolarimeter provided information on the nature and size distribution of the stratospheric aerosols. These balloon measurements with high precision and high vertical resolution are relevant to qualify the dynamical processes occurring in this region during summertime, the aerosols variability, the bromine abundance and establish a reference state of the polar summer stratosphere. The data set is completed by satellite data offering large spatial coverage of the region of interest. Data analysis is made using relevant dynamical (trajectory calculations, contour advection model) and chemistry-transport models (CTM) to highlight major mechanisms that control the distribution of tracers, aerosols and bromine. An

  3. Young Researchers Engaged in Educational Outreach to Increase Polar Literacy

    NASA Astrophysics Data System (ADS)

    Raymond, M.; Baeseman, J.; Xavier, J.; Kaiser, B.; Vendrell-Simon, B.

    2008-12-01

    The Association of Polar Early Career Scientists (APECS) grew out of the 4th International Polar Year (IPY-4) 2007-08 and is an international and interdisciplinary organization of over 1200 undergraduate and graduate students, postdoctoral researchers, early faculty members, educators and others with interests in Polar Regions and the wider cryosphere from more than 40 countries. Our aims are to stimulate interdisciplinary and international research collaborations, and develop effective future leaders in polar research, education and outreach. As potentially one of the major legacies of IPY-4, APECS members have been at the forefront of increasing scientific knowledge and public interest in the polar regions, centered around global climate change, and enhancing scientific understanding, media attention, primary and secondary school (K-12) educational programs, undergraduate institutions, and public literacy campaigns. Research and Educational Outreach activities by APECS members during IPY-4 have improved both our understanding and the communication of all aspects of the Polar Regions and the importance of their broader global connections. APECS National Committees have run Polar Contests where young researchers partnered with teachers and students to develop curriculum and activities to share their research, have participated in many field based communication exchanges and are mentoring youth to pursue careers in science, and enhancing the public perception of scientists through photo, video and museum exhibits. In cooperation with the IPY Teachers Network and the IPY IPO, APECS is developing a polar education resource book that will feature education and outreach activities by young researchers, as well as provide examples of classroom activities for teachers to incorporate polar literacy into their curriculum and a How-To guide for researchers interested in conducting education and outreach. As young researchers interactively share their excitement and

  4. RHIC Polarized proton operation

    SciTech Connect

    Huang, H.; Ahrens, L.; Alekseev, I.G.; Aschenauer, E.; Atoian, G.; Bai, M.; Bazilevsky, A.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Connolly, R.; Dion, A.; D'Ottavio, T.; Drees, K.A.; Fischer, W.; Gardner, C.; Glenn, J.W.; Gu, X.; Harvey, M.; Hayes, T.; Hoff, L.; Hulsart, R.L.; Laster, J.; Liu, C.; Luo, Y.; MacKay, W.W.; Makdisi, Y.; Marr, G.J.; Marusic, A.; Meot, F.; Mernick, K.; Michnoff, R,; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Poblaguev, A.; Ptitsyn, V.; Ranjibar, V.; Robert-Demolaize, G.; Roser, T.; J.; Severino, F.; Schmidke, B.; Schoefer, V.; Severino, F.; Smirnov, D.; Smith, K.; Steski, D.; Svirida, D.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J. Wang, G.; Wilinski, M.; Yip, K.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2011-03-28

    The Relativistic Heavy Ion Collider (RHIC) operation as the polarized proton collider presents unique challenges since both luminosity(L) and spin polarization(P) are important. With longitudinally polarized beams at the experiments, the figure of merit is LP{sup 4}. A lot of upgrades and modifications have been made since last polarized proton operation. A 9 MHz rf system is installed to improve longitudinal match at injection and to increase luminosity. The beam dump was upgraded to increase bunch intensity. A vertical survey of RHIC was performed before the run to get better magnet alignment. The orbit control is also improved this year. Additional efforts are put in to improve source polarization and AGS polarization transfer efficiency. To preserve polarization on the ramp, a new working point is chosen such that the vertical tune is near a third order resonance. The overview of the changes and the operation results are presented in this paper. Siberian snakes are essential tools to preserve polarization when accelerating polarized beams to higher energy. At the same time, the higher order resonances still can cause polarization loss. As seen in RHIC, the betatron tune has to be carefully set and maintained on the ramp and during the store to avoid polarization loss. In addition, the orbit control is also critical to preserve polarization. The higher polarization during this run comes from several improvements over last run. First we have a much better orbit on the ramp. The orbit feedback brings down the vertical rms orbit error to 0.1mm, much better than the 0.5mm last run. With correct BPM offset and vertical realignment, this rms orbit error is indeed small. Second, the jump quads in the AGS improved input polarization for RHIC. Third, the vertical tune was pushed further away from 7/10 snake resonance. The tune feedback maintained the tune at the desired value through the ramp. To calibrate the analyzing power of RHIC polarimeters at any energy above

  5. Matroshka DOSTEL measurements onboard the International Space Station (ISS)

    NASA Astrophysics Data System (ADS)

    Labrenz, Johannes; Burmeister, Soenke; Berger, Thomas; Heber, Bernd; Reitz, Guenther

    2015-12-01

    This paper presents the absorbed dose and dose equivalent rate measurements achieved with the DOSimetry TElescope (DOSTEL) during the two Matroshka (MTR) experiment campaigns in 2004/2005 (MTR-1) and 2007/2008 (MTR-2B). The comparison between the inside (MTR-2B) and outside (MTR-1) mission has shown that the shielding thickness provided by the International Space Station (ISS) spacecraft hull has a minor effect on the radiation exposure caused by Galactic Cosmic Rays (GCR). The exposure varies with the solar modulation of the GCR, too. Particles from Earth's radiation belts are effectively shielded by the spacecraft hull, and thus the contribution to the radiation exposure is lower for the inside measurement during MTR-2B. While the MTR-DOSTEL absorbed dose rate shows a good agreement with passive detectors of the MTR experiment for the MTR-2B mission phase, the MTR-1 absorbed dose rates from MTR-DOSTEL measurements are much lower than those obtained by a nearby passive detector. Observed discrepancies between the MTR-DOSTEL measurements and the passive detectors located nearby could be explained by the additional exposure to an enhanced flux of electrons trapped between L-parameter 2.5 and 3.5 caused by solar storms in July 2004.

  6. The Polar Insulation Investigation

    ERIC Educational Resources Information Center

    Urban-Rich, Juanita

    2006-01-01

    In this article, the author developed an activity called "The Polar Insulation Investigation." This activity builds on students' natural interest in "things polar" and introduces them to animal adaptations in a unique way. The aim of the exploration is to determine the role of animal coverings (e.g., blubber, fur, and feathers) and to see which is…

  7. Our Polar Past

    ERIC Educational Resources Information Center

    Clary, Renee; Wandersee, James

    2009-01-01

    The study of polar exploration is fascinating and offers students insights into the history, culture, and politics that affect the developing sciences at the farthest ends of Earth. Therefore, the authors think there is value in incorporating polar exploration accounts within modern science classrooms, and so they conducted research to test their…

  8. Polar Science Is Cool!

    ERIC Educational Resources Information Center

    Weeks, Sophie

    2012-01-01

    Children are fascinated by the fact that polar scientists do research in extremely cold and dangerous places. In the Arctic they might be viewed as lunch by a polar bear. In the Antarctic, they could lose toes and fingers to frostbite and the wind is so fast it can rip skin off. They camp on ice in continuous daylight, weeks from any form of…

  9. Polarized Light: Three Demonstrations.

    ERIC Educational Resources Information Center

    Goehmann, Ruth; Welty, Scott

    1984-01-01

    Describes three demonstrations used in the Chicago Museum of Science and Industry polarized light show. The procedures employed are suitable for the classroom by using smaller polarizers and an overhead projector. Topic areas include properties of cellophane tape, nondisappearing arrows, and rope through a picket fence. (JN)

  10. Mechanism of lunar polarization.

    PubMed

    Hopfield, J J

    1966-03-18

    A theoretical model to explain the negative polarization of moonlight at small lunar phase angles is developed. The model is based on the polarization of light in the diffraction region bordering the geometric shadow of an opaque dielectric obstacle. PMID:17817298

  11. Polarization and polarization fatigue in ferroelectrics

    NASA Astrophysics Data System (ADS)

    Du, Xiaofeng

    This thesis addresses some fundamental issues in ferroelectricity and its applications through a computational and experimental effort. It focuses on a variety of perovskite-type ferroelectric oxides and investigates the physical basis for spontaneous polarization, domain wall dynamics, and texture development in thin film applications. The dipole-dipole interactions between ionic species in perovskite-type materials have been calculated to determine the local field and the lattice instability. Different ferroelectric and anti-ferroelectric polarization transitions can be realized by taking into account the structure distortion of the parent perovskites. We find the local field is enhanced by short range disorder and its nature varies from disorder to disorder, causing polarization transitions in non-(100) directions. The molecular field theory has also been extended to layered perovskites, which favors in-plane polarization over c-polarization. These theoretical predictions are in agreement with the experimental observations of various perovskites and layered perovskites in both single crystal and thin film forms. Domain switching in PZT has been studied by probing the frequency dependency of polarization hysteresis. A picture of thermally activated domain wall movement is established from the frequency spectra of coercive field. The field dependence of domain wall bulging and the nature of the binding between pinning obstacles and the walls are inferred from such a study. Consistent with this picture, polarization fatigue can be defined as a process of increasing the resistance from pinning defects to domain wall motion. The chemical species that act as pinning defects have been identified through model experiments that control carrier injection, electrode interfaces, and film compositions. Based on these observations, a methodology is proposed to evaluate and predict the fatigue damage of both PZT and layered perovskite thin films. Processing of layered

  12. OUTCOMES OF THE FIFTH INTERNATIONAL CONFERENCE ON PEDIATRIC MECHANICAL CIRCULATORY SUPPORT SYSTEMS AND PEDIATRIC CARDIOPULMONARY PERFUSION

    PubMed Central

    Ündar, Akif

    2009-01-01

    The overall objective of the Conference was to bring together internationally know clinicians, bioengineers, and basic scientists involved in research on pediatric mechanical cardiac support systems and pediatric cardiopulmonary bypass procedures. The primary focus was to explicitly describe the problems with current pediatric mechanical circulatory support systems, methods, and techniques during acute and chronic support. The organizers were able to bring together respected international scholars from over 25 different countries at past conferences that has already made a significant impact on the treatment of pediatric cardiac patients during the past three years. Over 1,300 participants (250–300 participants each year) from many countries, including Argentina, Australia, Austria, Belgium, Brazil, Canada, China, Finland, France, Germany, Greece, Ireland, Italy, Japan, Kuwait, Netherlands, New Zealand, Poland, South Korea, Saudi Arabia, Scotland, Spain, Switzerland, Taiwan, Turkey, the United Kingdom, and the United States, have participated in the 2005, 2006, 2007, 2008, and 2009 events. To date, The Fifth International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion is the only conference solely dedicated to pediatric cardiac devices used during acute and chronic mechanical circulatory support. There is no other national or international conference to precisely define the problems with pediatric cardiac patients, and to suggest solutions with new methodologies and devices for pediatric patients, but specifically for neonates and infants. PMID:20021466

  13. Parallel Polarization State Generation

    PubMed Central

    She, Alan; Capasso, Federico

    2016-01-01

    The control of polarization, an essential property of light, is of wide scientific and technological interest. The general problem of generating arbitrary time-varying states of polarization (SOP) has always been mathematically formulated by a series of linear transformations, i.e. a product of matrices, imposing a serial architecture. Here we show a parallel architecture described by a sum of matrices. The theory is experimentally demonstrated by modulating spatially-separated polarization components of a laser using a digital micromirror device that are subsequently beam combined. This method greatly expands the parameter space for engineering devices that control polarization. Consequently, performance characteristics, such as speed, stability, and spectral range, are entirely dictated by the technologies of optical intensity modulation, including absorption, reflection, emission, and scattering. This opens up important prospects for polarization state generation (PSG) with unique performance characteristics with applications in spectroscopic ellipsometry, spectropolarimetry, communications, imaging, and security. PMID:27184813

  14. Polarization of clouds

    NASA Astrophysics Data System (ADS)

    Goloub, Philippe; Herman, Maurice; Parol, Frederic

    1995-12-01

    This paper reports the main results concerning polarization by clouds derived from POLDER (polarization and directionality of earth's reflectances) airborne version. These results tend to confirm the high information content in the polarization (phase, altimetry). The preliminary results of EUCREX'94 (European Cloud Radiation Experiment) evidenced the drastically different polarized signatures for ice crystals and water droplets. Here we report systematic and statistically significative observations over the whole EUCREX data set. The results show that the cirrus exhibit their own signature. Preliminary observations performed during CLEOPATRA'91 (Cloud Experiment Ober Pfaffenhofen And Transport) and EUCREX'94 campaigns have shown the feasibility of cloud altimetry using spectral information (443 nm and 865 nm) of the polarized light over liquid water droplets clouds. Altimetry technique has been generalized on ASTEX-SOFIA'92 and EUCREX'94 data sets. All these results are presented and discussed in this paper.

  15. Precision Polarization of Neutrons

    NASA Astrophysics Data System (ADS)

    Martin, Elise; Barron-Palos, Libertad; Couture, Aaron; Crawford, Christopher; Chupp, Tim; Danagoulian, Areg; Estes, Mary; Hona, Binita; Jones, Gordon; Klein, Andi; Penttila, Seppo; Sharma, Monisha; Wilburn, Scott

    2009-05-01

    Determining polarization of a cold neutron beam to high precision is required for the next generation neutron decay correlation experiments at the SNS, such as the proposed abBA and PANDA experiments. Precision polarimetry measurements were conducted at Los Alamos National Laboratory with the goal of determining the beam polarization to the level of 10-3 or better. The cold neutrons from FP12 were polarized using optically polarized ^3He gas as a spin filter, which has a highly spin-dependent absorption cross section. A second ^ 3He spin filter was used to analyze the neutron polarization after passing through a resonant RF spin rotator. A discussion of the experiment and results will be given.

  16. Parallel Polarization State Generation

    NASA Astrophysics Data System (ADS)

    She, Alan; Capasso, Federico

    2016-05-01

    The control of polarization, an essential property of light, is of wide scientific and technological interest. The general problem of generating arbitrary time-varying states of polarization (SOP) has always been mathematically formulated by a series of linear transformations, i.e. a product of matrices, imposing a serial architecture. Here we show a parallel architecture described by a sum of matrices. The theory is experimentally demonstrated by modulating spatially-separated polarization components of a laser using a digital micromirror device that are subsequently beam combined. This method greatly expands the parameter space for engineering devices that control polarization. Consequently, performance characteristics, such as speed, stability, and spectral range, are entirely dictated by the technologies of optical intensity modulation, including absorption, reflection, emission, and scattering. This opens up important prospects for polarization state generation (PSG) with unique performance characteristics with applications in spectroscopic ellipsometry, spectropolarimetry, communications, imaging, and security.

  17. Parallel Polarization State Generation.

    PubMed

    She, Alan; Capasso, Federico

    2016-01-01

    The control of polarization, an essential property of light, is of wide scientific and technological interest. The general problem of generating arbitrary time-varying states of polarization (SOP) has always been mathematically formulated by a series of linear transformations, i.e. a product of matrices, imposing a serial architecture. Here we show a parallel architecture described by a sum of matrices. The theory is experimentally demonstrated by modulating spatially-separated polarization components of a laser using a digital micromirror device that are subsequently beam combined. This method greatly expands the parameter space for engineering devices that control polarization. Consequently, performance characteristics, such as speed, stability, and spectral range, are entirely dictated by the technologies of optical intensity modulation, including absorption, reflection, emission, and scattering. This opens up important prospects for polarization state generation (PSG) with unique performance characteristics with applications in spectroscopic ellipsometry, spectropolarimetry, communications, imaging, and security. PMID:27184813

  18. Cell polarity: mechanochemical patterning.

    PubMed

    Goehring, Nathan W; Grill, Stephan W

    2013-02-01

    Nearly every cell type exhibits some form of polarity, yet the molecular mechanisms vary widely. Here we examine what we term 'chemical systems' where cell polarization arises through biochemical interactions in signaling pathways, 'mechanical systems' where cells polarize due to forces, stresses and transport, and 'mechanochemical systems' where polarization results from interplay between mechanics and chemical signaling. To reveal potentially unifying principles, we discuss mathematical conceptualizations of several prototypical examples. We suggest that the concept of local activation and global inhibition - originally developed to explain spatial patterning in reaction-diffusion systems - provides a framework for understanding many cases of cell polarity. Importantly, we find that the core ingredients in this framework - symmetry breaking, self-amplifying feedback, and long-range inhibition - involve processes that can be chemical, mechanical, or even mechanochemical in nature. PMID:23182746

  19. Polarized gamma-ray emission from the crab.

    PubMed

    Dean, A J; Clark, D J; Stephen, J B; McBride, V A; Bassani, L; Bazzano, A; Bird, A J; Hill, A B; Shaw, S E; Ubertini, P

    2008-08-29

    Pulsar systems accelerate particles to immense energies. The detailed functioning of these engines is still poorly understood, but polarization measurements of high-energy radiation may allow us to locate where the particles are accelerated. We have detected polarized gamma rays from the vicinity of the Crab pulsar using data from the spectrometer on the International Gamma-Ray Astrophysics Laboratory satellite. Our results show polarization with an electric vector aligned with the spin axis of the neutron star, demonstrating that a substantial fraction of the high-energy electrons responsible for the polarized photons are produced in a highly ordered structure close to the pulsar. PMID:18755970

  20. Commissioning of polarized-proton and antiproton beams at Fermilab

    SciTech Connect

    Yokosawa, A.

    1988-05-04

    The author described the polarized-proton and polarized-antiproton beams up to 200 GeV/c at Fermilab. The beam line, called MP, consists of the 400-m long primary and 350-m long secondary beam line followed by 60-m long experimental hall. We discuss the characteristics of the polarized beams. The Fermilab polarization projects are designated at E-581/704 initiated and carried out by an international collaboration, Argonne (US), Fermilab (US), Kyoto-Kyushu-Hiroshima-KEK (Japan), LAPP (France), Northwestern University (US), Los Alamos Laboratory (US), Rice (US), Saclay (France), Serpukhov (USSR), INFN Trieste (Italy), and University of Texas (US).

  1. Molecular content of polar-ring galaxies

    NASA Astrophysics Data System (ADS)

    Combes, F.; Moiseev, A.; Reshetnikov, V.

    2013-06-01

    We have searched for CO lines in a sample of 21 new morphologically determined polar-ring galaxies (of which nine are kinematically confirmed), obtained from a wide search in the Galaxy Zoo project by Moiseev and collaborators. Polar-ring galaxies (PRGs) are a unique class of objects, tracing special episodes in the galaxy mass assembly: they can be formed through galaxy interaction and merging, but also through accretion from cosmic filaments. Furthermore, they enable the study of dark matter haloes in three dimensions. The polar ring itself is a sub-system rich in gas, where molecular gas is expected, and new stars are formed. Among the sample of 21 PRGs, we have detected five CO-rich systems, that can now be followed up with higher spatial resolution. Their average molecular mass is 9.4 × 109M⊙, and their average gas fraction is 27% of their baryonic mass, with a range from 15 to 43%, implying that they have just accreted a large amount of gas. The position of the detected objects in the velocity-magnitude diagram is offset from the Tully-Fisher relation of normal spirals, as was already found for PRGs. This work is part of our multi-wavelength project to determine the detailed morphology and dynamics of PRGs, test through numerical models their formation scenario, and deduce their dark matter content and 3D-shape. Based on observations carried out with the IRAM 30 m telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain).Spectra of detections are available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (ftp://130.79.128.5">130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/554/A11

  2. PolarTREC: Successful Methods and Tools for Attaining Broad Educational Impacts with Interdisciplinary Polar Science

    NASA Astrophysics Data System (ADS)

    Warburton, J.; Timm, K. M.; Owens, R.; Warnick, W. K.

    2008-12-01

    PolarTREC--Teachers and Researchers Exploring and Collaborating, a program of the Arctic Research Consortium of the U.S. (ARCUS), is a National Science Foundation (NSF)-funded International Polar Year (IPY) project in which K-12 educators participate in hands-on field experiences in the polar regions, working closely with IPY scientists as a pathway to improving science education. Developing long-term teacher- researcher collaborations through PolarTREC ensures up-to-date climate change science content will permeate the K-12 education system long after the IPY. By infusing education with the cutting edge science from the polar regions, PolarTREC has already shown an increase in student and public knowledge of and interest in the polar regions and global climate change. Preliminary evaluations have shown that PolarTREC's program activities have many positive impacts on educators and their ability to teach science concepts and improve their teaching methods. Additionally, K-12 students polled in interest surveys showed significant changes regarding the importance of understanding the polar regions as a person in today's world. Researchers have been overwhelmingly satisfied with PolarTREC and cited several specific strengths, including the program's crucial link between the teachers' field research experiences and their classroom and the extensive training provided to teachers prior to their expedition. This poster will focus on other successful components of the PolarTREC program and how researchers and organizations might use these tools to reach out to the public for long-term impacts. Best practices include strategies for working with educators and the development of an internet-based platform for teachers and researchers to interact with the public, combining several communication tools such as online journals and forums, real-time Internet seminars, lesson plans, activities, audio, and other educational resources that address a broad range of scientific topics

  3. PolarTREC: Successful Methods and Tools for Attaining Broad Educational Impacts with Interdisciplinary Polar Science

    NASA Astrophysics Data System (ADS)

    Timm, K. M.; Warburton, J.; Owens, R.; Warnick, W. K.

    2008-12-01

    PolarTREC--Teachers and Researchers Exploring and Collaborating, a program of the Arctic Research Consortium of the U.S. (ARCUS), is a National Science Foundation (NSF)-funded International Polar Year (IPY) project in which K-12 educators participate in hands-on field experiences in the polar regions, working closely with IPY scientists as a pathway to improving science education. Developing long-term teacher- researcher collaborations through PolarTREC ensures up-to-date climate change science content will permeate the K-12 education system long after the IPY. By infusing education with the cutting edge science from the polar regions, PolarTREC has already shown an increase in student and public knowledge of and interest in the polar regions and global climate change. Preliminary evaluations have shown that PolarTREC's program activities have many positive impacts on educators and their ability to teach science concepts and improve their teaching methods. Additionally, K-12 students polled in interest surveys showed significant changes regarding the importance of understanding the polar regions as a person in today's world. Researchers have been overwhelmingly satisfied with PolarTREC and cited several specific strengths, including the program's crucial link between the teachers' field research experiences and their classroom and the extensive training provided to teachers prior to their expedition. This presentation will focus on other successful components of the PolarTREC program and how researchers and organizations might use these tools to reach out to the public for long-term impacts. Best practices include strategies for working with educators and the development of an internet-based platform for teachers and researchers to interact with the public, combining several communication tools such as online journals and forums, real-time Internet seminars, lesson plans, activities, audio, and other educational resources that address a broad range of scientific

  4. Polar Perspectives on Art and Science

    NASA Astrophysics Data System (ADS)

    Rennermalm, A. K.; Salzman, H.; Gustafson, D.

    2014-12-01

    The rapidly changing climate and environment in polar regions in the 20th and 21st centuries are well documented by scientists. Yet, this understanding is not well disseminated to students and the general public because the language of science is often inaccessible to these groups. To increase participation in science about the changing Polar regions, we organized a series of interdisciplinary events at Rutgers, The State University of New Jersey, in 2013/14 called "Polar Perspectives on Art and Science". This series brought five artist/scholars to Rutgers and reached a broad audience of students, faculty and the general public. Accompanying this series were two high-profile events. First, the Zimmerli Art Museum's academic-year-long exhibit, "Glacial Perspectives," displayed paintings and photographs by Diane Burko documenting rapidly changing glacial, and polar landscapes. Second, the "Let Us Talk About Water" event included a screening of the documentary "Chasing Ice" followed by a panel discussion at the Rutgers Cinema. Financial support was provided by Zimmerli Art Museum's Andrew W. Mellon Endowment Fund, Consortium of Universities for the Advancement of Hydrological Sciences, Inc., Rutgers Centers for Global Advancement and International Affairs, GAIA, and many other Rutgers institutes and departments. Student feedback on the "Polar Perspectives on Science and Art" suggest that art was effective in enhancing engagement and understanding of contemporary polar change. Furthermore, the many events created a forum for reoccurring and stimulating discussions among people with their academic home in widely different disciplines, including humanities, and physical and social sciences.

  5. The Association of Polar Early Career Scientists - Developing a Continuum of Polar Research

    NASA Astrophysics Data System (ADS)

    Pope, A.; Baeseman, J. L.

    2011-12-01

    Established in 2006 by young researchers in the early stages of the International Polar Year (IPY), the Association of Polar Early Career Scientists (APECS) has evolved into the pre-eminent international organization for polar researchers at early stages of their careers. Now comprising around 2600 members from approximately 74 countries, APECS represents a body of students, postdoctoral researchers, early faculty members, educators and others with interests in Polar Regions and the cryosphere with the key aim of raising the profile of polar research by providing a continuum of leadership that is both international and interdisciplinary in focus, and stimulating collaborative projects in research, education and outreach. APECS provides a strong voice for young researchers, enabling information sharing between early-career and more established professionals, promoting and organizing science, education and outreach events, and being actively involved with other organizations in the support of polar research. These activities are guided by three overarching goals: *Facilitate international and interdisciplinary networking to share ideas and experiences and to develop new research directions and collaborations; *Provide opportunities for professional career development; and *Promote education and outreach as integral components of polar research and to stimulate future generations of polar researchers. This presentation highlights the major achievements of APECS since its inception as well as future steps that APECS plans to take to ensure its sustainability. Since its founding, APECS has strived to develop strong partnerships with international organizations and scientific bodies. This network has not only facilitated early-career representation on an international level but has also furthered many education and outreach opportunities for young polar researchers. APECS core programs that include career development workshops and panels (including several associated

  6. Interplanetary magnetic sector polarity inferred from polar geomagnetic field observations

    NASA Technical Reports Server (NTRS)

    Friis-Christensen, E.; Lassen, K.; Wilcox, J. M.; Gonzalez, W.; Colburn, D. S.

    1971-01-01

    In order to infer the interplanetary sector polarity from polar geomagnetic field diurnal variations, measurements were carried out at Godhavn and Thule (Denmark) Geomagnetic Observatories. The inferred interplanetary sector polarity was compared with the polarity observed at the same time by Explorer 33 and 35 magnetometers. It is shown that the polarity (toward or away from the sun) of the interplanetary magnetic field can be reliably inferred from observations of the polar cap geomagnetic fields.

  7. Neutron Polarizers Based on Polarized 3He

    SciTech Connect

    William M. Snow

    2005-05-01

    The goal of this work, which is a collaborative effort between Indiana University, NIST, and Hamilton College, is to extend the technique of polarized neutron scattering into new domains by the development and application of polarized 3He-based neutron spin filters. After the IPNS experiment which measured Zeeman sp[litting in surface scattered neutrons using a polarized 3He cell as a polarization analyzer transporterd by car from Bloomington to Chicago, the Indiana work focused on technical developments to improve the 3He polarization of the Indiana compression system. The compression system was rebuilt with a new valve system which allows gas trapped in the dead volume of the compressors at the end of the piston stroke to be exhausted and conducted back to the optical pumping cell where it can be repolarized. We also incorporated a new intermediate storage volume made at NIST from 1720 glass which will reduce polarization losses between the compressors. Furthermore, we improved the stability of the 1083 nm laser by cooling the LMA rod. We achieved 60% 3he polarization in the optical pumping cell and 87% preservation of the polarization during compression. In parallel we built a magnetically-shielded transport solenoid for use on neutron scattering instruments such as POSY which achieves a fractional field uniformity of better than 10-3 per cm. The field was mapped using an automated 3D field mapping system for in-situ measurement of magnetic field gradients Diluted magnetic semiconductors offer many exciting opportunities for investigation of spintronic effects in solids and are certain to be one of the most active areas of condensed matter physics over then next several years. These materials can act as efficient spin injectors for devices that make use of spin-dependent transport phenomena. We just (late July 2002) finished a neutron reflectivity experiment at NIST on a GaMnAs trilayer film. This material is a ferromagnetic semiconductor which is of interest

  8. Polarization at the SLC

    SciTech Connect

    Moffeit, K.C.

    1988-10-01

    The Stanford Linear collider was designed to accommodate polarized electron beams. Longitudinally polarized electrons colliding with unpolarized positrons at a center of mass energy near the Z/sup 0/ mass can be used as novel and sensitive probes of the electroweak process. A gallium arsenide based photon emission source will provide a beam of longitudinally polarized electrons of about 45 percent polarization. A system of bend magnets and a superconducting solenoid will be used to rotate the spins so that the polarization is preserved while the 1.21 GeV electrons are stored in the damping ring. Another set of bend magnets and two superconducting solenoids orient the spin vectors so that longitudinal polarization of the electrons is achieved at the collision point with the unpolarized positrons. A system to monitor the polarization based on Moller and Compton scattering will be used. Nearly all major components have been fabricated and tested. Subsystems of the source and polarimeters have been installed, and studies are in progress. The installation and commissioning of the entire system will take place during available machine shutdown periods as the commissioning of SLC progresses. 8 refs., 16 figs., 1 tab.

  9. Review of Polarized Ion Sources

    NASA Astrophysics Data System (ADS)

    Zelenski, A.

    2016-02-01

    Recent progress in polarized ion sources development is reviewed. New techniques for production of polarized H‑ ion (proton), D‑ (D+) and 3He++ ion beams will be discussed. A novel polarization technique was successfully implemented for the upgrade of the RHIC polarized H‑ ion source to higher intensity and polarization. In this technique, a proton beam inside the high magnetic field solenoid is produced by ionization of the atomic hydrogen beam (from an external source) in the He-gas ionizer cell. Polarized electron capture from the optically-pumped Rb vapor further produces proton polarization (Optically Pumped Polarized Ion Source technique). The upgraded source reliably delivered beam for the 2013 polarized run in RHIC at S = 510 GeV. This was a major factor contributing to RHIC polarization increase to over 60 % for colliding beams. Feasibility studies of a new polarization technique for polarized 3He++ source based on BNL Electron Beam Ion Source is also discussed.

  10. Polarized positrons and electrons at the linear collider

    NASA Astrophysics Data System (ADS)

    Moortgat-Pick, G.; Abe, T.; Alexander, G.; Ananthanarayan, B.; Babich, A. A.; Bharadwaj, V.; Barber, D.; Bartl, A.; Brachmann, A.; Chen, S.; Clarke, J.; Clendenin, J. E.; Dainton, J.; Desch, K.; Diehl, M.; Dobos, B.; Dorland, T.; Dreiner, H. K.; Eberl, H.; Ellis, J.; Flöttmann, K.; Fraas, H.; Franco-Sollova, F.; Franke, F.; Freitas, A.; Goodson, J.; Gray, J.; Han, A.; Heinemeyer, S.; Hesselbach, S.; Hirose, T.; Hohenwarter-Sodek, K.; Juste, A.; Kalinowski, J.; Kernreiter, T.; Kittel, O.; Kraml, S.; Langenfeld, U.; Majerotto, W.; Martinez, A.; Martyn, H.-U.; Mikhailichenko, A.; Milstene, C.; Menges, W.; Meyners, N.; Mönig, K.; Moffeit, K.; Moretti, S.; Nachtmann, O.; Nagel, F.; Nakanishi, T.; Nauenberg, U.; Nowak, H.; Omori, T.; Osland, P.; Pankov, A. A.; Paver, N.; Pitthan, R.; Pöschl, R.; Porod, W.; Proulx, J.; Richardson, P.; Riemann, S.; Rindani, S. D.; Rizzo, T. G.; Schälicke, A.; Schüler, P.; Schwanenberger, C.; Scott, D.; Sheppard, J.; Singh, R. K.; Sopczak, A.; Spiesberger, H.; Stahl, A.; Steiner, H.; Wagner, A.; Weber, A. M.; Weiglein, G.; Wilson, G. W.; Woods, M.; Zerwas, P.; Zhang, J.; Zomer, F.

    2008-05-01

    The proposed International Linear Collider (ILC) is well-suited for discovering physics beyond the Standard Model and for precisely unraveling the structure of the underlying physics. The physics return can be maximized by the use of polarized beams. This report shows the paramount role of polarized beams and summarizes the benefits obtained from polarizing the positron beam, as well as the electron beam. The physics case for this option is illustrated explicitly by analyzing reference reactions in different physics scenarios. The results show that positron polarization, combined with the clean experimental environment provided by the linear collider, allows to improve strongly the potential of searches for new particles and the identification of their dynamics, which opens the road to resolve shortcomings of the Standard Model. The report also presents an overview of possible designs for polarizing both beams at the ILC, as well as for measuring their polarization.

  11. North Polar Dunes

    NASA Technical Reports Server (NTRS)

    2006-01-01

    23 January 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark sand dunes in the north polar region of Mars. Surrounding much of the north polar ice cap are fields of sand dunes. In this case, the strongest winds responsible for the dunes blew off the polar cap (not seen here), from the north-northwest (upper left).

    Location near: 76.5oN, 63.7oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer

  12. GUIDE FOR POLARIZED NEUTRONS

    DOEpatents

    Sailor, V.L.; Aichroth, R.W.

    1962-12-01

    The plane of polarization of a beam of polarized neutrons is changed by this invention, and the plane can be flipped back and forth quicitly in two directions in a trouble-free manner. The invention comprises a guide having a plurality of oppositely directed magnets forming a gap for the neutron beam and the gaps are spaced longitudinally in a spiral along the beam at small stepped angles. When it is desired to flip the plane of polarization the magnets are suitably rotated to change the direction of the spiral of the gaps. (AEC)

  13. PolarTREC—A Model Program for Taking Polar Literacy into the Future

    NASA Astrophysics Data System (ADS)

    Warburton, J.; Timm, K.; Larson, A. M.

    2009-12-01

    Polar TREC—Teachers and Researchers Exploring and Collaborating, is a three-year (2007-2009) NSF-funded International Polar Year (IPY) teacher professional development program that advances Science, Technology, Engineering, and Mathematics (STEM) education by improving teacher content knowledge and instructional practices through Teacher Research Experiences (TRE) in the Arctic and Antarctic. Leveraging profound changes and fascinating science taking place in the polar regions, PolarTREC broadly disseminates activities and products to students, educators, researchers, and the public, connecting them with the Arctic and Antarctica and sustaining the widespread interest in the polar regions and building on the enthusiasm that was generated through IPY. Central to the PolarTREC Teacher Research Experience Model, over 40 teachers have spent two to eight weeks participating in hands-on research in the polar regions and sharing their experiences with diverse audiences via live events, online multimedia journals, and interactive bulletin boards. The Connecting Arctic/Antarctic Researchers and Educators (CARE) Network unifies learning community members participants, alumni, and others, developing a sustainable association of education professionals networking to share and apply polar STEM content and pedagogical skills. Educator and student feedback from preliminary results of the program evaluation has shown that PolarTREC’s comprehensive program activities have many positive impacts on educators and their ability to teach science concepts and improve their teaching methods. Additionally, K-12 students polled in interest surveys showed significant changes in key areas including amount of time spent in school exploring research activities, importance of understanding science for future work, importance of understanding the polar regions as a person in today’s world, as well as increased self-reported knowledge and interest in numerous science content areas. Building

  14. Polar Environmental Monitoring

    NASA Technical Reports Server (NTRS)

    Nagler, R. G.; Schulteis, A. C.

    1979-01-01

    The present and projected benefits of the polar regions were reviewed and then translated into information needs in order to support the array of polar activities anticipated. These needs included measurement sensitivities for polar environmental data (ice/snow, atmosphere, and ocean data for integrated support) and the processing and delivery requirements which determine the effectiveness of environmental services. An assessment was made of how well electromagnetic signals can be converted into polar environmental information. The array of sensor developments in process or proposed were also evaluated as to the spectral diversity, aperture sizes, and swathing capabilities available to provide these measurements from spacecraft, aircraft, or in situ platforms. Global coverage and local coverage densification options were studied in terms of alternative spacecraft trajectories and aircraft flight paths.

  15. Mercury's South Polar Region

    NASA Video Gallery

    This animation shows 89 wide-angle camera (WAC) images of Mercury’s south polar region acquired by the Mercury Dual Imaging System (MDIS) over one complete Mercury solar day (176 Earth days). Thi...

  16. Interferometric polarization control

    SciTech Connect

    Chuss, David T.; Wollack, Edward J.; Moseley, S. Harvey; Novak, Giles

    2006-07-20

    We develop the Jones and Mueller matrices for structures that allow control of the path length difference between two linear orthogonal polarizations and consider the effect of placing multiple devices in series. Specifically, we find that full polarization modulation (measurement of Stokes Q, U, and V) can be achieved by placing two such modulators in series if the relative angles of the beam-splitting grids with respect to the analyzer orientation are appropriately chosen. Such a device has several potential advantages over a spinning wave plate modulator for measuring astronomical polarization in the far infrared through millimeter: (i) The use of small, linear motions eliminates the need for cryogenic rotational bearings; (ii) the phase flexibility allows measurement of circular as well as linear polarization; and (iii) this architecture allows for both multiwavelength and broadband modulation. We also present initial laboratory results.

  17. Polarization contrast vision

    NASA Astrophysics Data System (ADS)

    Pugh, Edward N.

    1990-05-01

    An attempt is made to establish the possibility that the geometry of certain classes of vertebrate photoreceptors results in a birefringence that allows the animals to utilize the state of polarization of light striking their retinas as a meaningful stimulus parameter. Simulate the photoreceptors as dielectric waveguides using a simple physical model, and augment this theoretical work with empirical measurements of the light guiding properties of photoreceptors in isolated pieces of retina from a green sunfish (Lepomis cyanellus). With a classical conditioning paradigm, this fish's sensitivity to light is modulated by the orientation of the plane of polarization of linearly polarized light. This functional dependence was predicted by a hypothetical antagonistic mechanism between twin cones of two orientations in the animal's retinal mosaic. Further study is planned for the nature of the stimulus to which the fish is sensitive by creating a camera that will generate images based purely upon the contrast between orthogonal polarizations at each point in space.

  18. Realistic simulation of the Space-borne Compton Polarimeter POLAR

    NASA Astrophysics Data System (ADS)

    Xiao, Hualin

    2016-07-01

    POLAR is a compact wide field space-borne detector dedicated for precise measurements of the linear polarization of hard x-rays emitted by transient sources. Its energy range sensitivity is optimized for the detection of the prompt emission of Gamma-ray bursts (GRBs). POLAR is developed by an international collaboration of China, Switzerland and Poland. It is planned to be launched into space in 2016 onboard the Chinese space laboratory TG2. The energy range of POLAR spans between 50 keV and 500 keV. POLAR detects gamma rays with an array of 1600 plastic scintillator bars read out by 25 muti-anode PMTs (MAPMTs). Polarization measurements use Compton scattering process and are based on detection of energy depositions in the scintillator bars. Reconstruction of the polarization degree and polarization angle of GRBs requires comparison of experimental modulation curves with realistic simulations of the full instrument response. In this paper we present a method to model and parameterize the detector response including efficiency of the light collection, contributions from crosstalk and non-uniformity of MAPMTs as well as dependency on low energy detection thresholds and noise from readout electronics. The performance of POLAR for determination of polarization is predicted with such realistic simulations and carefully cross-checked with dedicated laboratory tests.

  19. Active polarization descattering.

    PubMed

    Treibitz, Tali; Schechner, Yoav Y

    2009-03-01

    Vision in scattering media is important but challenging. Images suffer from poor visibility due to backscattering and attenuation. Most prior methods for scene recovery use active illumination scanners (structured and gated), which can be slow and cumbersome, while natural illumination is inapplicable to dark environments. The current paper addresses the need for a non-scanning recovery method, that uses active scene irradiance. We study the formation of images under widefield artificial illumination. Based on the formation model, the paper presents an approach for recovering the object signal. It also yields rough information about the 3D scene structure. The approach can work with compact, simple hardware, having active widefield, polychromatic polarized illumination. The camera is fitted with a polarization analyzer. Two frames of the scene are taken, with different states of the analyzer or polarizer. A recovery algorithm follows the acquisition. It allows both the backscatter and the object reflection to be partially polarized. It thus unifies and generalizes prior polarization-based methods, which had assumed exclusive polarization of either of these components. The approach is limited to an effective range, due to image noise and illumination falloff. Thus, the limits and noise sensitivity are analyzed. We demonstrate the approach in underwater field experiments. PMID:19147870

  20. Bringing Polar Science to the Classroom

    NASA Astrophysics Data System (ADS)

    Bruccoli, A.; Madsen, J. M.; Porter, M.

    2004-12-01

    The NSF sponsored IceCube (OPP-0236449) and Teachers Experiencing Antarctica and the Arctic (TEA) projects have developed a model for engaging K-12 teachers in a variety of scientific disciplines using polar science as a unifying theme. An intensive workshop, Science in the Ice, provided teachers with background content knowledge and seed ideas for activities aligned with national teaching standards. These activities were used to support the introduction of authentic science investigations related to current polar research in the classroom. The pilot workshop, sponsored by the NSF supported Math-Science Partnership SCALE (0227016), demonstrated the viability of this approach for involving a continuum of teachers from novice to master in a meaningful professional development model that can lead to sustainable classroom changes. This model for teacher professional development is based on the premise that the most robust educational outreach efforts involve teachers that are prepared, supported, and connected to a network of researchers and educators. This network can also serve to both stimulate interest in polar research and as a vehicle for delivering classroom materials related to the International Polar Year. An overview of Science in the Ice will be provided to show how the natural fascination with extreme environments can be used to introduce on-going research to the classroom from multiple disciplines---glaciology, geology, and astrophysics---with a common thread of polar science. The case for involving teachers now to fully capitalize on the potential of the International Polar Year, by providing professional development opportunities including field experiences with researchers, will be made.

  1. Fusion of a polarized projectile with a polarized target

    SciTech Connect

    Christley, J.A.; Johnson, R.C.; Thompson, I.J.

    1995-07-15

    The fusion cross sections for a polarized target with both unpolarized and polarized projectiles are studied. Expressions for the observables are given for the case when both nuclei are polarized. Calculations for fusion of an aligned {sup 165}Ho target with {sup 16}O and polarized {sup 7}Li beams are presented.

  2. Polarization transfer of bremsstrahlung arising from spin-polarized electrons.

    PubMed

    Märtin, R; Weber, G; Barday, R; Fritzsche, Y; Spillmann, U; Chen, W; DuBois, R D; Enders, J; Hegewald, M; Hess, S; Surzhykov, A; Thorn, D B; Trotsenko, S; Wagner, M; Winters, D F A; Yerokhin, V A; Stöhlker, Th

    2012-06-29

    We report on a study of the polarization transfer between transversely polarized incident electrons and the emitted x rays for electron-atom bremsstrahlung. By means of Compton polarimetry we performed for the first time an energy-differential measurement of the complete properties of bremsstrahlung emission related to linear polarization, i.e., the degree of linear polarization as well as the orientation of the polarization axis. For the high-energy end of the bremsstrahlung continuum the experimental results for both observables show a high sensitivity on the initial electron spin polarization and prove that the polarization orientation is virtually independent of the photon energy. PMID:23004992

  3. Rectilinear lattices of polarization vortices with various spatial polarization distributions.

    PubMed

    Fu, Shiyao; Zhang, Shikun; Wang, Tonglu; Gao, Chunqing

    2016-08-01

    In this paper, we propose a type of rectilinear lattices of polarization vortices, each spot in which has mutually independent, and controllable spatial polarization distributions. The lattices are generated by two holograms under special design. In the experiment, the holograms are encoded on two spatial light modulators, and the results fit very well with theory. Our scheme makes it possible to generate multiple polarization vortices with various polarization distributions simultaneously, for instance, radially and azimuthally polarized beams, and can be used in the domains as polarization-based data transmission system, optical manufacture, polarization detection and so on. PMID:27505812

  4. EU-PolarNet: Connecting Science with Society

    NASA Astrophysics Data System (ADS)

    Biebow, N.

    2015-12-01

    The rapid changes occurring in the Polar Regions are significantly influencing global climate with consequences for global society. European and international polar research has contributed critical knowledge to identifying the processes behind these rapid changes but datasets from the Polar Regions are still insufficient to fully understand and more effectively predict the effects of change on our climate and society. This situation can only be improved by a more holistic integrated scientific approach, a higher degree of coordination of polar research and closer cooperation with all relevant actors on an international level. The objectives of EU-PolarNet are to establish an on-going dialogue between policy-makers, business and industry leaders, local communities and scientists to increase mutual understanding and identify new ways of working that will deliver economic and societal benefits. The results of this dialogue will be brought together in an Integrated European Research Programme that will be co-designed with all relevant stakeholders and coordinated with the activities of polar research nations beyond Europe. This programme will be accompanied by a feasible implementation plan to provide the Polar community with the capability to define the nature of environmental risks so that governments can design policy measures to mitigate them and businesses and other stakeholders benefit from the opportunities that are opening up in the Polar Regions.

  5. Polarized nuclear target based on parahydrogen induced polarization

    SciTech Connect

    D. Budker, M.P. Ledbetter, S. Appelt, L.S. Bouchard, B. Wojtsekhowski

    2012-12-01

    We discuss a novel concept of a polarized nuclear target for accelerator fixed-target scattering experiments, which is based on parahydrogen induced polarization (PHIP). One may be able to reach a 33% free-proton polarization in the ethane molecule. The potential advantages of such a target include operation at zero magnetic field, fast ({approx}100 HZ) polarization oscillation (akin to polarization reversal), and operation with large intensity of an electron beam.

  6. Polarized nuclear target based on parahydrogen induced polarization

    NASA Astrophysics Data System (ADS)

    Budker, D.; Ledbetter, M. P.; Appelt, S.; Bouchard, L. S.; Wojtsekhowski, B.

    2012-12-01

    We discuss a novel concept of a polarized nuclear target for accelerator fixed-target scattering experiments, which is based on parahydrogen induced polarization (PHIP). One may be able to reach a 33% free-proton polarization in the ethane molecule. The potential advantages of such a target include operation at zero magnetic field, fast (˜100 Hz) polarization oscillation (akin to polarization reversal), and operation with large intensity of an electron beam.

  7. In Brief: European cooperation in polar research

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2009-07-01

    A new European Polar Framework agreement aims to increase research cooperation, streamline links between many European national research programs in the Arctic and Antarctic, and possibly create international research teams similar to the Integrated Ocean Drilling Program. The new framework includes commitments to collaborate on new multinational research initiatives and to have national polar programs converge where appropriate. “Recent environmental shifts in the poles have been large and rapid. By linking together Europe's polar research more closely we can get a better grasp on the wide-ranging series of changes taking place,” said Paul Egerton, executive director of the European Science Foundation's European Polar Board, which aims to facilitate cooperation among various organizations. The agreement was signed on 24 June by 26 European scientific institutions, including the British Antarctic Survey; the Agency of Culture, Education, Research and the Church Affairs, Greenland; the Alfred-Wegener-Institut für Polar- und Meeresforschung, Germany; Italy's Programma Nazionale di Ricerche in Antartide; Norway's Norsk Polarinstitutt; and the Romanian Antarctic Foundation.

  8. Undulator-Based Production of Polarized Photons

    SciTech Connect

    Professor Kirk McDonald

    2008-05-29

    "Project Title: Undulator-Based Production of Polarized Photons" DOE Contract Number: FG02-04ER41355 Principal Investigator: Prof. Kirk McDonald Period of Performance: 09/10/2004 thru 08/31/2006 This award was to fund Princeton's activity on SLAC experiment E166, "Undulator-Based Production of Polarized Positrons" which was performed at SLAC during June and September 2005. Princeton U. fabricated a magnetic spectrometer for this experiment, and participated in the commissioning, operation, and analysis of the experiment, for which Prof. McDonald was a co-spokesperson. The experiment demonstrated that an intense positron beam with 80% longitudinal polarization could be generated by conversion of MeVenergy circularly polarized photons in a thin target, which photons were generated by passage of high-energy electrons through a helical undulator. This technique has since been adopted as the baseline for the polarized positron source of the proposed International Linear Collider. Results of the experiment have been published in Physical Review Letters, vol 100, p 210801 (2008) [see attached .pdf file], and a longer paper is in preparation.

  9. Polar low dynamics

    SciTech Connect

    Montgomery, M.T.; Farrell, B.F. )

    1992-12-15

    Polar lows are intense subsynoptic-scale cyclones that form over high-latitude oceans in association with deep cumulus convection and strong ambient baroclinicity. Recent observations indicate that polar lows are generally initiated by a nonaxisymmetric interaction between a surface disturbance and an upper-level mobile trough. Extant theories of polar low formation preclude study of such a process since they either constrain their models to be axisymmetric, or do not explicitly account for his transient interaction. In this work the physics of interacting upper- and lower-level potential vorticity structures is studied as an initial-value problem using a three-dimensional nonlinear geostrophic momentum model that incorporates moist processes and includes strong baroclinic dynamics. Model results illustrate the rapid formation of an intense small-scale cyclone whose structure is consistent with observations of mature polar lows. A conceptual model of polar low development is proposed. In the first stage of development, called induced self-development, a mobile upper trough initiates a rapid low-level spinup due to the enhanced omega response in a conditionally neutral baroclinic atmosphere. A secondary development follows, called diabatic destabilization, that is associated with the production of low-level potential vorticity by diabatic processes. Diabatic destabilization represents a simple mechanism for maintaining the intensity of polar lows until they reach land. In exceptional instances of negligible upper-level forcing, the latter may also describe the gradual intensification of small-scale cyclones in regions of sustained neutrality and surface baroclinicity. Ideas regarding polar low equilibration and prospects for a unified theory of arctic and midlatitude cyclones are discussed. 75 refs., 4 figs., 1 tab.

  10. Sequential Polarity-Reversing Circuit

    NASA Technical Reports Server (NTRS)

    Labaw, Clayton C.

    1994-01-01

    Proposed circuit reverses polarity of electric power supplied to bidirectional dc motor, reversible electro-mechanical actuator, or other device operating in direction depending on polarity. Circuit reverses polarity each time power turned on, without need for additional polarity-reversing or direction signals and circuitry to process them.

  11. Cylindrically polarized nondiffracting optical pulses

    NASA Astrophysics Data System (ADS)

    Ornigotti, Marco; Conti, Claudio; Szameit, Alexander

    2016-07-01

    We extend the concept of radially and azimuthally polarized optical beams to the polychromatic domain by introducing cylindrically polarized nondiffracting optical pulses. In particular, we discuss in detail the case of cylindrically polarized X-waves, both in the paraxial and nonparaxial regime. The explicit expressions for the electric and magnetic fields of cylindrically polarized X-waves are also reported.

  12. Polarization twist in perovskite ferrielectrics

    PubMed Central

    Kitanaka, Yuuki; Hirano, Kiyotaka; Ogino, Motohiro; Noguchi, Yuji; Miyayama, Masaru; Moriyoshi, Chikako; Kuroiwa, Yoshihiro

    2016-01-01

    Because the functions of polar materials are governed primarily by their polarization response to external stimuli, the majority of studies have focused on controlling polar lattice distortions. In some perovskite oxides, polar distortions coexist with nonpolar tilts and rotations of oxygen octahedra. The interplay between nonpolar and polar instabilities appears to play a crucial role, raising the question of how to design materials by exploiting their coupling. Here, we introduce the concept of ‘polarization twist’, which offers enhanced control over piezoelectric responses in polar materials. Our experimental and theoretical studies provide direct evidence that a ferrielectric perovskite exhibits a large piezoelectric response because of extended polar distortion, accompanied by nonpolar octahedral rotations, as if twisted polarization relaxes under electric fields. The concept underlying the polarization twist opens new possibilities for developing alternative materials in bulk and thin-film forms. PMID:27586824

  13. Polarization twist in perovskite ferrielectrics.

    PubMed

    Kitanaka, Yuuki; Hirano, Kiyotaka; Ogino, Motohiro; Noguchi, Yuji; Miyayama, Masaru; Moriyoshi, Chikako; Kuroiwa, Yoshihiro

    2016-01-01

    Because the functions of polar materials are governed primarily by their polarization response to external stimuli, the majority of studies have focused on controlling polar lattice distortions. In some perovskite oxides, polar distortions coexist with nonpolar tilts and rotations of oxygen octahedra. The interplay between nonpolar and polar instabilities appears to play a crucial role, raising the question of how to design materials by exploiting their coupling. Here, we introduce the concept of 'polarization twist', which offers enhanced control over piezoelectric responses in polar materials. Our experimental and theoretical studies provide direct evidence that a ferrielectric perovskite exhibits a large piezoelectric response because of extended polar distortion, accompanied by nonpolar octahedral rotations, as if twisted polarization relaxes under electric fields. The concept underlying the polarization twist opens new possibilities for developing alternative materials in bulk and thin-film forms. PMID:27586824

  14. Polar low monitoring

    NASA Astrophysics Data System (ADS)

    Bobylev, Leonid; Zabolotskikh, Elizaveta; Mitnik, Leonid

    2010-05-01

    Polar lows are intense mesoscale atmospheric low pressure weather systems, developing poleward of the main baroclinic zone and associated with high surface wind speeds. Small size and short lifetime, sparse in-situ observations in the regions of their development complicate polar low study. Our knowledge of polar lows and mesocyclones has come almost entirely during the period of satellite remote sensing since, by virtue of their small horizontal scale, it was rarely possible to analyse these lows on conventional weather charts using only the data from the synoptic observing network. However, the effects of intense polar lows have been felt by coastal communities and seafarers since the earliest times. These weather systems are thought to be responsible for the loss of many small vessels over the centuries, although the nature of the storms was not understood and their arrival could not be predicted. The actuality of the polar low research is stipulated by their high destructive power: they are a threat to such businesses as oil and gas exploration, fisheries and shipping. They could worsen because of global warming: a shrinking of sea ice around the North Pole, which thawed to its record minimum in the summer of 2007, is likely to give rise to more powerful storms that form only over open water and can cause hurricane-strength winds. Therefore, study of polar lows, their timely detection, tracking and forecasting represents a challenge for today meteorology. Satellite passive microwave data, starting from Special Sensor Microwave Imager (SSM/I) onboard Defense Meteorological Satellite Program (DMSP) satellite, remain invaluable source of regularly available remotely sensed data to study polar lows. The sounding in this spectral range has several advantages in comparison with observations in visible and infrared ranges and Synthetic Aperture Radar (SAR) data: independence on day time and clouds, regularity and high temporal resolution in Polar Regions. Satellite

  15. Polarization of Starlight

    NASA Astrophysics Data System (ADS)

    Whittet, D. C. B.

    The polarization of starlight is universally attributed to directional extinction arising when dust grains along the line of sight are aligned in the presence of a magnetic field. This phenomenon provides a powerful tool for studying the optical properties of the dust (size, shape, refractive index) and for charting the galactic magnetic field. Current observational constraints at all wavelengths are consistent with a picture in which only the larger grains in the size range responsible for extinction are efficient polarizers. Small grains are much less well aligned and/or more isotropic in shape than large grains. The polarizing grains include silicates, but it is not clear whether they contain appreciable quantities of carbon. The degree of alignment is highly sensitive to ambient physical conditions as well as to particle size. The polarization efficiency per unit extinction declines with increasing density within dark clouds, hindering attempts to map the intracloud magnetic field. However, spectropolarimetric studies of interstellar ice absorption features seen in deeply embedded YSOs indicate that mantled grains within dense molecular clouds can be surprisingly efficient polarizers, suggesting that a qualitatively different alignment mechanism is operating compared with diffuse regions of the ISM. This talk will present a brief overview of key observations and their interpretation, highlight areas of uncertainty, and suggest avenues of future research. The physics of grain alignment is reviewed elsewhere in this meeting (see paper by Roberge).

  16. POLARBEAR CMB Polarization Experiment

    NASA Astrophysics Data System (ADS)

    Nishino, H.; Ade, P.; Akiba, Y.; Anthony, A.; Arnold, K.; Barron, D.; Boettger, D.; Borrill, J.; Chapmann, S.; Chinone, Y.; Dobbs, M. A.; Errard, J.; Fabbian, G.; Feng, C.; Flanigan, D.; Fuller, G.; Ghribi, A.; Grainger, W.; Halverson, N.; Hasegawa, M.; Hattori, K.; Hazumi, M.; Holzapfel, W. L.; Howard, J.; Hyland, P.; Inoue, Y.; Jaffe, A.; Jaehnig, G.; Kaneko, Y.; Katayama, N.; Keating, B.; Kermish, Z.; Kimura, N.; Kisner, T.; Lee, A. T.; Le Jeune, M.; Linder, E.; Lungu, M.; Matsuda, F.; Matsumura, T.; Miller, N. J.; Morii, H.; Moyerman, S.; Myers, M. J.; O'Brient, R.; Okamura, T.; Paar, H.; Peloton, J.; Quealy, E.; Reichardt, C. L.; Richards, P. L.; Ross, C.; Shimizu, A.; Shimon, M.; Shimmin, C.; Sholl, M.; Siritanasak, P.; Spieler, H.; Stebor, N.; Steinbach, B.; Stompor, R.; Suzuki, A.; Suzuki, J.; Tanaka, K.; Tomaru, T.; Tucker, C.; Yadav, A.; Zahn, O.

    POLARBEAR is a ground-based experiment in the Atacama desert in hile, measuring the polarization of the Cosmic Microwave Background (CMB) radiation. One of the science goals of POLARBEAR is to detect the B-mode polarization pattern of the CMB produced by primordial gravitational waves from the epoch of inflation. The detection of the B-mode polarization provides strong evidence for inflationary cosmological models. POLARBEAR is expected to reach a sensitivity to the tensor-to-scalar ratio r = 0.025 at 95% confidence level, using the data from two years of observation. With a beam size of 3.5 arcminutes, POLARBEAR is also sensitive to B-mode polarization signals at small-angular scales produced by weak gravitational lensing of large-scale structure. POLARBEAR is expected to provide a constraint on the sum of neutrino masses because of their effect on the large-scale structure. POLARBEAR was deployed in late 2011 and started observing in early 2012 at 150 GHz with an array of 1,274 polarization sensitive antenna-coupled Transition Edge Sensor (TES) bolometers. The current status of the POLARBEAR experiment is reported.

  17. Polarized protons at RHIC

    SciTech Connect

    Makdisi, Y.

    1992-10-01

    The approval for construction of the Relativistic Heavy Ion Collider (RHIC) provides a potential opportunity to collide polarized proton beams at energies up to 500 GeV in the center of mass and high luminosities approaching 2 {times} 10{sup 32}/cm{sup 2}/sec. This capability is enhanced by the fact that the AGS has already accelerated polarized protons and relies on the newly completed Accumulator/Booster for providing the required polarized proton intensity and a system of spin rotators (Siberian snakes) to retain the polarization. The RHIC Spin Collaboration was formed and submitted a Letter of Intent to construct this polarized collider capability and utilize its physics opportunities. In this presentation, I will discuss the plans to upgrade the AGS, the proposed layout of the RHIC siberian snakes, and timetables. The physics focus is the measurement of the spin dependent parton distributions with such accessible probes including high p(t) jets, direct photons, and Drell Yan. The attainable sensitivities and the progress that has been reached in defining the detector requirements will be outlined.

  18. Polarized protons at RHIC

    SciTech Connect

    Makdisi, Y.

    1992-01-01

    The approval for construction of the Relativistic Heavy Ion Collider (RHIC) provides a potential opportunity to collide polarized proton beams at energies up to 500 GeV in the center of mass and high luminosities approaching 2 {times} 10{sup 32}/cm{sup 2}/sec. This capability is enhanced by the fact that the AGS has already accelerated polarized protons and relies on the newly completed Accumulator/Booster for providing the required polarized proton intensity and a system of spin rotators (Siberian snakes) to retain the polarization. The RHIC Spin Collaboration was formed and submitted a Letter of Intent to construct this polarized collider capability and utilize its physics opportunities. In this presentation, I will discuss the plans to upgrade the AGS, the proposed layout of the RHIC siberian snakes, and timetables. The physics focus is the measurement of the spin dependent parton distributions with such accessible probes including high p(t) jets, direct photons, and Drell Yan. The attainable sensitivities and the progress that has been reached in defining the detector requirements will be outlined.

  19. A Compact Polarization Imager

    NASA Technical Reports Server (NTRS)

    Thompson, Karl E.; Rust, David M.; Chen, Hua

    1995-01-01

    A new type of image detector has been designed to analyze the polarization of light simultaneously at all picture elements (pixels) in a scene. The Integrated Dual Imaging Detector (IDID) consists of a polarizing beamsplitter bonded to a custom-designed charge-coupled device with signal-analysis circuitry, all integrated on a silicon chip. The IDID should simplify the design and operation of imaging polarimeters and spectroscopic imagers used, for example, in atmospheric and solar research. Other applications include environmental monitoring and robot vision. Innovations in the IDID include two interleaved 512 x 1024 pixel imaging arrays (one for each polarization plane), large dynamic range (well depth of 10(exp 6) electrons per pixel), simultaneous readout and display of both images at 10(exp 6) pixels per second, and on-chip analog signal processing to produce polarization maps in real time. When used with a lithium niobate Fabry-Perot etalon or other color filter that can encode spectral information as polarization, the IDID can reveal tiny differences between simultaneous images at two wavelengths.

  20. Artificial polarization components

    NASA Astrophysics Data System (ADS)

    Cescato, L.; Gluch, Ekkehard; Stork, Wilhelm; Streibl, Norbert

    1990-07-01

    High frequency surface relief structures are optically anisotropic and show interesting polarisation properties 1 . These properties can be used to produce polarizations components such as wave plates polarizers. polarizing beamsplitters etc. Our experimental results show that even gratings with relatively low spatial frequency ( periods A ) exhibit a strong phase retardation and can be used as quarter-wave plates. k INTRODUC11ON The artificial birefringence exhibited by ultrahigh frequency gratings of dielectric materials can be used to produce various polarization components2 . Such components have applications in integrated optics as well as in free space optics. In order to produce the high spatial frequencies complex processes such as electron-beam lithography and reactive ion etching are needed. We show in this paper that sinusoidal holographic gratings in photoresist exhibit also a strong phase ret even at relatively long periods. L EXPERIMENTAL MEASUREMENTS To obtain the phase retardation of a lower frequency ( period A ) grating a simple setup as used by Enger and 2 can be applied. In our case however there are three measurements necessary to obtain the phase retardation because transmission of the two perpendicularly polarized beams is different from each other. I GRATING PRODUCTION grating 2 3 4 5 6 7 8 9 period (pmj 0. 74 0. 74 0. 61 0. 54 0. 46 0. 32 0. 54 0. 54 0. 54 ne (sec) 60

  1. Circularly Polarized Microwave Antenna Element with Very Low Off-Axis Cross-Polarization

    NASA Technical Reports Server (NTRS)

    Greem. David; DuToit, Cornelis

    2013-01-01

    The goal of this work was to improve off-axis cross-polarization performance and ease of assembly of a circularly polarized microwave antenna element. To ease assembly, the initial design requirement of Hexweb support for the internal circuit part, as well as the radiating disks, was eliminated. There is a need for different plating techniques to improve soldering. It was also desirable to change the design to eliminate soldering as well as the need to use the Hexweb support. Thus, a technique was developed to build the feed without using solder, solving the lathing and soldering issue. Internal parts were strengthened by adding curvature to eliminate Hexweb support, and in the process, the new geometries of the internal parts opened the way for improving the off-axis cross-polarization performance as well. The radiating disks curvatures were increased for increased strength, but it was found that this also improved crosspolarization. Optimization of the curvatures leads to very low off-axis cross-polarization. The feed circuit was curved into a cylinder for improved strength, eliminating Hexweb support. An aperture coupling feed mechanism eliminated the need for feed pins to the disks, which would have required soldering. The aperture coupling technique also improves cross-polarization performance by effectively exciting the radiating disks very close to the antenna s central axis of symmetry. Because of the shape of the parts, it allowed for an all-aluminum design bolted together and assembled with no solder needed. The advantage of a solderless design is that the reliability is higher, with no single-point failure (solder), and no need for special plating techniques in order to solder the unit together. The shapes (curved or round) make for a more robust build without extra support materials, as well as improved offaxis cross-polarization.

  2. Polarized beams at RHIC

    SciTech Connect

    Roser, T.

    1995-11-01

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven allows for the unique possibility of colliding two 250 GeV polarized proton beams at luminosities of up to 2 {times} 10{sup 32} cm{sup {minus}2} s{sup {minus}1}. A partial Siberian Snake in the AGS has recently been successfully tested and full Siberian Snakes, spin rotators, and polarimeters for RHIC are being developed to make the acceleration of polarized beams to 250 GeV possible. High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes, which will allow the study of the spin structure of the proton and also the verification of the many well documented expectations of spin effects in perturbative QCD and parity violation in W and Z production.

  3. A lunar polar expedition

    NASA Technical Reports Server (NTRS)

    Dowling, Richard; Staehle, Robert L.; Svitek, Tomas

    1992-01-01

    Advanced exploration and development in harsh environments require mastery of basic human survival skill. Expeditions into the lethal climates of Earth's polar regions offer useful lessons for tommorrow's lunar pioneers. In Arctic and Antarctic exploration, 'wintering over' was a crucial milestone. The ability to establish a supply base and survive months of polar cold and darkness made extensive travel and exploration possible. Because of the possibility of near-constant solar illumination, the lunar polar regions, unlike Earth's may offer the most hospitable site for habitation. The World Space Foundation is examining a scenario for establishing a five-person expeditionary team on the lunar north pole for one year. This paper is a status report on a point design addressing site selection, transportation, power, and life support requirements.

  4. South Polar Layers

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-516, 17 October 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows eroded, stair-stepped layers in the south polar region of Mars. These layers have been considered, for the past three decades, to consist of a mixture of dust and ice. The Mars Polar Lander (MPL) mission was designed to test this hypothesis. However, sadly, MPL was lost during descent in December 1999. This exposure of south polar layered material is located near 86.3oS, 187.7oW. The image covers an area 3 km (1.9 mi) wide and is illuminated by sunlight from the upper left.

  5. Polarized Light from Jupiter

    NASA Technical Reports Server (NTRS)

    2001-01-01

    These images taken through the wide angle camera near closest approach in the deep near-infrared methane band, combined with filters which sense electromagnetic radiation of orthogonal polarization, show that the light from the poles is polarized. That is, the poles appear bright in one image, and dark in the other. Polarized light is most readily scattered by aerosols. These images indicate that the aerosol particles at Jupiter's poles are small and likely consist of aggregates of even smaller particles, whereas the particles at the equator and covering the Great Red Spot are larger. Images like these will allow scientists to ascertain the distribution, size and shape of aerosols, and consequently, the distribution of heat, in Jupiter's atmosphere.

  6. South Polar Scarps

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-438, 31 July 2003

    The terrain of the south polar residual ice cap, made up mostly of frozen carbon dioxide, has come to be known by many as 'swiss cheese terrain,' because many areas of the cap resemble slices of swiss cheese. However, not all of the south polar cap looks like a tasty lunch food. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a series of curving scarps formed by erosion and sublimation of carbon dioxide from the south polar cap. This area is located near 86.3oS, 51.2oW. The image is illuminated by sunlight from the upper left; the area is about 1.5 km (0.9 mi) wide.

  7. Diurnal polar motion

    NASA Technical Reports Server (NTRS)

    Mcclure, P.

    1973-01-01

    An analytical theory is developed to describe diurnal polar motion in the earth which arises as a forced response due to lunisolar torques and tidal deformation. Doodson's expansion of the tide generating potential is used to represent the lunisolar torques. Both the magnitudes and the rates of change of perturbations in the earth's inertia tensor are included in the dynamical equations for the polar motion so as to account for rotational and tidal deformation. It is found that in a deformable earth with Love's number k = 0.29, the angular momentum vector departs by as much as 20 cm from the rotation axis rather than remaining within 1 or 2 cm as it would in a rigid earth. This 20 cm separation is significant in the interpretation of submeter polar motion observations because it necessitates an additional coordinate transformation in order to remove what would otherwise be a 20 cm error source in the conversion between inertial and terrestrial reference systems.

  8. POLARIZED NEUTRONS IN RHIC

    SciTech Connect

    COURANT,E.D.

    1998-04-27

    There does not appear to be any obvious way to accelerate neutrons, polarized or otherwise, to high energies by themselves. To investigate the behavior of polarized neutrons the authors therefore have to obtain them by accelerating them as components of heavier nuclei, and then sorting out the contribution of the neutrons in the analysis of the reactions produced by the heavy ion beams. The best neutron carriers for this purpose are probably {sup 3}He nuclei and deuterons. A polarized deuteron is primarily a combination of a proton and a neutron with their spins pointing in the same direction; in the {sup 3}He nucleus the spins of the two protons are opposite and the net spin (and magnetic moment) is almost the same as that of a free neutron. Polarized ions other than protons may be accelerated, stored and collided in a ring such as RHIC provided the techniques proposed for polarized proton operation can be adapted (or replaced by other strategies) for these ions. To accelerate polarized particles in a ring, one must make provisions for overcoming the depolarizing resonances that occur at certain energies. These resonances arise when the spin tune (ratio of spin precession frequency to orbit frequency) resonates with a component present in the horizontal field. The horizontal field oscillates with the vertical motion of the particles (due to vertical focusing); its frequency spectrum is dominated by the vertical oscillation frequency and its modulation by the periodic structure of the accelerator ring. In addition, the magnet imperfections that distort the closed orbit vertically contain all integral Fourier harmonics of the orbit frequency.

  9. Microwave Frequency Polarizers

    NASA Technical Reports Server (NTRS)

    Ha, Vien The; Mirel, Paul; Kogut, Alan J.

    2013-01-01

    This article describes the fabrication and analysis of microwave frequency polarizing grids. The grids are designed to measure polarization from the cosmic microwave background. It is effective in the range of 500 to 1500 micron wavelength. It is cryogenic compatible and highly robust to high load impacts. Each grid is fabricated using an array of different assembly processes which vary in the types of tension mechanisms to the shape and size of the grids. We provide a comprehensive study on the analysis of the grids' wire heights, diameters, and spacing.

  10. South Polar Variety

    NASA Technical Reports Server (NTRS)

    2005-01-01

    28 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of linear troughs and mesas formed in the frozen carbon dioxide of the martian south polar residual cap. This image, obtained in May 2005, is a reminder that not all of the south polar cap landscapes resemble 'swiss cheese.'

    Location near: 86.7oS, 24.8oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  11. Ultracold polar KRb molecules

    NASA Astrophysics Data System (ADS)

    Neyenhuis, Brian; Chotia, Amodsen; Moses, Steven; Ye, Jun; Jin, Deborah

    2011-05-01

    Ultracold polar molecules in the quantum degenerate regime open the possibility of realizing quantum gases with long-range, and spatially anisotropic, interparticle interactions. Currently, we can create a gas of ultracold fermionic ground-state KRb molecules in with a peak density of 1012 cm-3 and a temperature just 1.4 times the Fermi temperature. We will report on efforts to further cool this gas of molecules. One possibility is to evaporatively cool a spin-polarized molecular Fermi gas confined in quasi-2D, where we would rely on dipole-dipole interactions for rethermalization. We acknowledge funding from NIST, NSF, and AFOSR-MURI.

  12. Polarization encoded color camera.

    PubMed

    Schonbrun, Ethan; Möller, Guðfríður; Di Caprio, Giuseppe

    2014-03-15

    Digital cameras would be colorblind if they did not have pixelated color filters integrated into their image sensors. Integration of conventional fixed filters, however, comes at the expense of an inability to modify the camera's spectral properties. Instead, we demonstrate a micropolarizer-based camera that can reconfigure its spectral response. Color is encoded into a linear polarization state by a chiral dispersive element and then read out in a single exposure. The polarization encoded color camera is capable of capturing three-color images at wavelengths spanning the visible to the near infrared. PMID:24690806

  13. Physics with Polarized Antiprotons

    SciTech Connect

    Lenisa, Paolo

    2008-04-30

    Polarized antiprotons will provide access to a wealth of double- (and single-) spin observables, thereby opening a window to physics uniquely accessible with the HESR at FAIR. This include a first direct measurement of the transversity distribution of the valence quarks in the proton and a first measurement of the moduli and phase of the time-like electric and magnetic form factors G{sub E,M} of the proton. Additional applications of a polarized antiproton beam can be forseen in hadron spectroscopy, and nucleon-antinucleon scattering.

  14. Femtosecond polarization pulse shaping.

    PubMed

    Brixner, T; Gerber, G

    2001-04-15

    We report computer-controlled femtosecond polarization pulse shaping where intensity, momentary frequency, and light polarization are varied as functions of time. For the first time to our knowledge, a pulse shaper is used to modulate the degree of ellipticity as well as the orientation of the elliptical principal axes within a single laser pulse by use of a 256-pixel two-layer liquid-crystal display inside a zero-dispersion compressor. Interferometric stability of the setup is not required. Complete pulse characterization is achieved by dual-channel spectral interferometry. This technology has a large range of applications, especially in the field of quantum control. PMID:18040384

  15. The physics of polarization

    NASA Astrophysics Data System (ADS)

    Landi Degl'Innocenti, Egidio

    This course is intended to give a description of the basic physical concepts which underlie the study and the interpretation of polarization phenomena. Apart from a brief historical introduction (Sect. 1), the course is organized in three parts. A first part (Sects. 2 - 6) covers the most relevant facts about the polarization phenomena that are typically encountered in laboratory applications and in everyday life. In Sect. 2, the modern description of polarization in terms of the Stokes parameters is recalled, whereas Sect. 3 is devoted to introduce the basic tools of laboratory polarimetry, such as the Jones calculus and the Mueller matrices. The polarization phenomena which are met in the reflection and refraction of a beam of radiation at the separation surface between two dielectrics, or between a dielectric and a metal, are recalled in Sect. 4. Finally, Sect. 5 gives an introduction to the phenomena of dichroism and of anomalous dispersion and Sect. 6 summarizes the polarization phenomena that are commonly encountered in everyday life. The second part of this course (Sects. 7-14) deals with the description, within the formalism of classical physics, of the spectro-polarimetric properties of the radiation emitted by accelerated charges. Such properties are derived by taking as starting point the Liénard and Wiechert equations that are recalled and discussed in Sect. 7 both in the general case and in the non-relativistic approximation. The results are developed to find the percentage polarization, the radiation diagram, the cross-section and the spectral characteristics of the radiation emitted in different phenomena particularly relevant from the astrophysical point of view. The emission of a linear antenna is derived in Sect. 8. The other Sections are devoted to Thomson scattering (Sect. 9), Rayleigh scattering (Sect. 10), Mie scattering (Sect. 11), bremsstrahlung radiation (Sect. 12), cyclotron radiation (Sect. 13), and synchrotron radiation (Sect. 14

  16. [A review on polarization information in the remote sensing detection].

    PubMed

    Gong, Jie-Qiong; Zhan, Hai-Gang; Liu, Da-Zhao

    2010-04-01

    Polarization is one of the inherent characteristics. Because the surface of the target structure, internal structure, and the angle of incident light are different, the earth's surface and any target in atmosphere under optical interaction process will have their own characteristic nature of polarization. Polarimetric characteristics of radiation energy from the targets are used in polarization remote sensing detection as detective information. Polarization remote sensing detection can get the seven-dimensional information of targets in complicated backgrounds, detect well-resolved outline of targets and low-reflectance region of objectives, and resolve the problems of atmospheric detection and identification camouflage detection which the traditional remote sensing detection can not solve, having good foreground in applications. This paper introduces the development of polarization information in the remote sensing detection from the following four aspects. The rationale of polarization remote sensing detection is the base of polarization remote sensing detection, so it is firstly introduced. Secondly, the present researches on equipments that are used in polarization remote sensing detection are particularly and completely expatiated. Thirdly, the present exploration of theoretical simulation of polarization remote sensing detection is well detailed. Finally, the authors present the applications research home and abroad of the polarization remote sensing detection technique in the fields of remote sensing, atmospheric sounding, sea surface and underwater detection, biology and medical diagnosis, astronomical observation and military, summing up the current problems in polarization remote sensing detection. The development trend of polarization remote sensing detection technology in the future is pointed out in order to provide a reference for similar studies. PMID:20545168

  17. How effective is an ethical international recruitment policy? Reflections on a decade of experience in England.

    PubMed

    Young, Ruth

    2013-07-01

    Using evidence from a 2006 postal survey of NHS organisations, plus eight case studies and source country interviews (India; Philippines; Zimbabwe; Poland; Spain) in 2007-2008, the paper explores the impacts of England's 'ethical' recruitment policy as it developed from the late 1990s onwards. It shows that a Code of Practice and bilateral agreements did positively influence the behaviour of NHS organisations and commercial agencies at the height of England's international recruitment drive from 2001 to 2006. However, such policies could only go so far; and other actions are needed to mitigate the downside effects of migration on source countries. One key step is an attitude change that sees countries like England receiving internationally mobile health professionals for the 'value added' that they bring--rather than regarding them primarily as a numerical addition or substitute for the domestically-trained workforce. Another is to plan and manage the domestic workforce in order to deliver on self-sufficiency ambitions. Finally, 'ethical' stances mean placing health professional recruitment/migration into wider development agendas--as a platform for training and skills development for the developing world. Overall, it was the winding down of England's active recruitment policy from 2006 together with subsequent general immigration and professional registration rule changes that had most influence on migration numbers. PMID:23602547

  18. RECENT ACTIVITIES OF THE NUCLEAR SMUGGLING INTERNATIONAL TECHNICAL WORKING GROUP TO THWART ILLICIT TRAFFICKING

    SciTech Connect

    Smith, D K; Biro, T; Chartier, B; Mayer, K; Niemeyer, S; Thompson, P

    2007-10-25

    The Nuclear Smuggling International Technical Working Group (ITWG) is an informal association of nuclear forensic practitioners working in partnership with law enforcement, first responder, and nuclear regulatory professionals that cooperate to deter the illicit trafficking of nuclear materials. The objective of the ITWG is to advance the science of nuclear forensics and to provide a common approach and effective technical solutions to governments who request assistance. the ITWG was chartered in 1996 and since that time 30 nations and organizations have participated in 12 annual meetings and two analytical round-robin trials involving plutonium and highly enriched uranium. A third analytical round-robin as well as several table-top exercises are planned for later in 2007-2008. International interest in the ITWG has grown in over the past five years measured by the number of participants at its annual meetings. This growth has spawned the ITWG Nuclear Forensics Laboratories as a companion technical affiliate focusing exclusively on the scientific aspects of nuclear forensics and nuclear smuggling incident response.

  19. The World Informatics Scene: ICSU, International Unions and Associations, Professional Society Activities

    NASA Astrophysics Data System (ADS)

    Fox, P.; Barton, C.

    2009-04-01

    Now that the Electronic Geophysical Year (2007-2008) has concluded, a substantial number of new coordination efforts under the heading of informatics have emerged. These efforts range from divisions/ sections in societies such as the Geological Society of America, the American Geophysical Union and the European Geosciences Union devoted to all aspects of informatics. In each case there has been a strong community response at their regular meetings. These society efforts are closer to the working scientists, technologists and data producers, and managers. At the same time, in a recognition for the need of a sustained activity such as eGY, the International Union of Geodesy and Geophysics (IUGG) has formed a Union Commission for Data and Information and the Committee on Data for Science and Technology (CODATA) approved a Task Group on eGY Earth and Space Science Data Interoperability. The International Council of Science's (ICSU) Strategic Committee on Information and Data (SCID) implementation report was approved by the ICSU general assembly in October 2008. ICSU's priority area assessment strategy for ICSU to play a leadership role in the coordination of data and information efforts world-wide. This report is being implemented and influences entities such as CODATA, and forms a new World Data System. This presentation will give details on the abovementioned activities and indicate an emerging synergy for Informatics across many discipline and the advancement of science and societal goals.

  20. Phase-Controlled Polarization Modulators

    NASA Technical Reports Server (NTRS)

    Chuss, D. T.; Wollack, E. J.; Novak, G.; Moseley, S. H.; Pisano, G.; Krejny, M.; U-Yen, K.

    2012-01-01

    We report technology development of millimeter/submillimeter polarization modulators that operate by introducing a a variable, controlled phase delay between two orthogonal polarization states. The variable-delay polarization modulator (VPM) operates via the introduction of a variable phase delay between two linear orthogonal polarization states, resulting in a variable mapping of a single linear polarization into a combination of that Stokes parameter and circular (Stokes V) polarization. Characterization of a prototype VPM is presented at 350 and 3000 microns. We also describe a modulator in which a variable phase delay is introduced between right- and left- circular polarization states. In this architecture, linear polarization is fully modulated. Each of these devices consists of a polarization diplexer parallel to and in front of a movable mirror. Modulation involves sub-wavelength translations of the mirror that change the magnitude of the phase delay.

  1. Variable polarity arc welding

    NASA Technical Reports Server (NTRS)

    Bayless, E. O., Jr.

    1991-01-01

    Technological advances generate within themselves dissatisfactions that lead to further advances in a process. A series of advances in welding technology which culminated in the Variable Polarity Plasma Arc (VPPA) Welding Process and an advance instituted to overcome the latest dissatisfactions with the process: automated VPPA welding are described briefly.

  2. Classical Demonstration of Polarization.

    ERIC Educational Resources Information Center

    Bauman, Robert P.; Moore, Dennis R.

    1980-01-01

    Presents a classical demonstration of polarization for high school students. The initial state of this model, which demonstrates the important concepts of the optical and quantum problems, was developed during the 1973 summer program on lecture demonstration at the U.S. Naval Academy. (HM)

  3. Optical neutron polarizers

    SciTech Connect

    Hayter, J.B.

    1990-01-01

    A neutron wave will be refracted by an appropriately varying potential. Optical neutron polarizers use spatially varying, spin- dependent potentials to refract neutrons of opposite spin states into different directions, so that an unpolarized beam will be split into two beams of complementary polarization by such a device. This paper will concentrate on two methods of producing spin-dependent potentials which are particularly well-suited to polarizing cold neutron beams, namely thin-film structures and field-gradient techniques. Thin-film optical devices, such as supermirror multilayer structures, are usually designed to deviate only one spin-state, so that they offer the possibility of making insertion (transmission) polarizers. Very good supermirrors may now be designed and fabricated, but it is not always straightforward to design mirror-based devices which are useful in real (divergent beam) applications, and some practical configurations will be discussed. Field-gradient devices, which are usually based on multipolar magnets, have tended to be too expensive for general use, but this may change with new developments in superconductivity. Dipolar and hexapolar configurations will be considered, with emphasis on the focusing characteristics of the latter. 21 refs., 7 figs.

  4. Polar processing project

    NASA Astrophysics Data System (ADS)

    Tom, C. N.; Davies, W. J.; Goycochea, J. F.

    1993-09-01

    The purpose of this project was to explore the use of polar processing techniques in SIGINT-related signal processing applications. An investigation of ways to apply the CORDIC arithmetic algorithm to signal processing problems, and an application of the TMC2330 Coordinate Transformer chip in a coprocessor or accelerator board for a Sun workstation are covered.

  5. The polarized EMC effect

    SciTech Connect

    W. Bentz; I. C. Cloet; A. W. Thomas

    2007-02-01

    We calculate both the spin independent and spin dependent nuclear structure functions in an effective quark theory. The nucleon is described as a composite quark-diquark state, and the nucleus is treated in the mean field approximation. We predict a sizable polarized EMC effect, which could be confirmed in future experiments.

  6. A Polarized Universe

    NASA Technical Reports Server (NTRS)

    Wanjek, Christopher

    2003-01-01

    The CMB polarization was produced as light scattered off a primordial cloud of protons and electrons nearly 14 billion years ago, about 400,000 years after the Big Bang. This marks the moment of recombination, when the universe finally cooled enough to allow electrons to join protons. The CMB is the light that broke through the fog.

  7. North Polar Ice Cap

    NASA Technical Reports Server (NTRS)

    1997-01-01

    North polar ice cap of Mars, as seen during mid summer in the northern hemisphere. The reddish areas consist of eolian dust, bright white areas consist of a mixture of water ice and dust, and the dark blue areas consist of sand dunes forming a huge 'collar' around the polar ice cap. (The colors have been enhanced with a decorrelation stretch to better show the color variability.) Shown here is an oblique view of the polar region, as seen with the Viking 1 spacecraft orbiting Mars over latitude 39 degrees north. The spiral bands consist of valleys which form by a combination of the Coriolis forces, wind erosion, and differential sublimation and condensation. In high-resolution images the polar caps are seen to consist of thick sequences of layered deposits, suggesting that cyclical climate changes have occurred on Mars. Cyclical climate changes are readily explained by quasi-periodic changes in the amount and distribution of solar heating resulting from perturbations in orbital and axial elements. Variations in the Earth's orbit have also been linked to the terrestrial climate changes during the ice ages.

  8. Anodic Polarization Curves Revisited

    ERIC Educational Resources Information Center

    Liu, Yue; Drew, Michael G. B.; Liu, Ying; Liu, Lin

    2013-01-01

    An experiment published in this "Journal" has been revisited and it is found that the curve pattern of the anodic polarization curve for iron repeats itself successively when the potential scan is repeated. It is surprising that this observation has not been reported previously in the literature because it immediately brings into…

  9. Optical polarizer material

    DOEpatents

    Ebbers, Christopher A.

    1999-01-01

    Several crystals have been identified which can be grown using standard single crystals growth techniques and which have a high birefringence. The identified crystals include Li.sub.2 CO.sub.3, LiNaCO.sub.3, LiKCO.sub.3, LiRbCO.sub.3 and LiCsCO.sub.3. The condition of high birefringence leads to their application as optical polarizer materials. In one embodiment of the invention, the crystal has the chemical formula LiK.sub.(1-w-x-y) Na.sub.(1-w-x-z) Rb.sub.(1-w-y-z) Cs.sub.(1-x-y-z) CO.sub.3, where w+x+y+z=1. In another embodiment, the crystalline material may be selected from a an alkali metal carbonate and a double salt of alkali metal carbonates, where the polarizer has a Wollaston configuration, a Glan-Thompson configuration or a Glan-Taylor configuration. A method of making an LiNaCO.sub.3 optical polarizer is described. A similar method is shown for making an LiKCO.sub.3 optical polarizer.

  10. Optical polarizer material

    DOEpatents

    Ebbers, C.A.

    1999-08-31

    Several crystals have been identified which can be grown using standard single crystals growth techniques and which have a high birefringence. The identified crystals include Li.sub.2 CO.sub.3, LiNaCO.sub.3, LiKCO.sub.3, LiRbCO.sub.3 and LiCsCO.sub.3. The condition of high birefringence leads to their application as optical polarizer materials. In one embodiment of the invention, the crystal has the chemical formula LiK.sub.(1-w-x-y) Na.sub.(1-w-x-z) Rb.sub.(1-w-y-z) Cs.sub.(1-x-y-z) CO.sub.3, where w+x+y+z=1. In another embodiment, the crystalline material may be selected from a an alkali metal carbonate and a double salt of alkali metal carbonates, where the polarizer has a Wollaston configuration, a Glan-Thompson configuration or a Glan-Taylor configuration. A method of making an LiNaCO.sub.3 optical polarizer is described. A similar method is shown for making an LiKCO.sub.3 optical polarizer.

  11. Planetary polarization nephelometer

    NASA Astrophysics Data System (ADS)

    Banfield, D.; Dissly, R.; Mishchenko, M.; Muñoz, O.; Roos-Serote, M.; Stam, D.; Volten, H.

    2004-02-01

    We have proposed to develop a polarization nephelometer for use on future planetary descent probes. It will measure both the scattered intensity and polarization phase functions of the aerosols it encounters descending through an atmosphere. These measurements will be taken at two wavelengths separated by about an octave, with one light source near 500nm and another near 1μm. Adding polarization measurements to the intensity phase functions greatly increases our ability to constrain the size distribution, shape and chemical composition of the sampled particles. There remain important questions about these parameters of the aerosols on Venus, the giant planets and Titan that can only be addressed with a nephelometer like ours. The NRC Planetary Sciences Decadal Survey has identified probe missions to Venus and Jupiter as a priority. On both of these missions, our proposed instrument would be an excellent candidate for flight. We also expect that future probe missions to Saturn, Uranus, Neptune or Titan would employ our instrument. It could also find use in Earth in situ aerosol studies. We will use a technique to simultaneously measure intensity and polarization phase functions that uses polarization modulation of a light source. This technique has been implemented in laboratory settings, but not with considerations to the environment on a planetary descent probe. We have proposed to design and build a flexible breadboard nephelometer to test the components and concepts of our approach. We would then test the device against well defined aerosols, ensuring that it accurately measures their expected intensity and polarization phase functions. With the knowledge gained in this flexible design, we would then design and build a breadboard polarization nephelometer more suited to integration on a planetary descent probe. To include traceability in the technical requirements of our device, we would also conduct an Observing System Simulation Experiment. In this study, we

  12. Titan's Polar Atmosphere

    NASA Astrophysics Data System (ADS)

    Flasar, F. M.; Achterberg, R. K.; Schinder, P. J.

    2015-12-01

    Cassini CIRS and Radio-Occultation measurements obtained in 2004-2015 have tracked the evolution of temperatures and winds in Titan's polar atmosphere, as the winter season shifted from the northern hemisphere to the southern. The dissolution of the strong circumpolar vortex initially seen in the northern hemisphere has been gradual. There is no evidence of the rapid distortion and disruption forced by planetary waves that can occur on Earth. Indeed, neither Cassini experiment has identified any thermal signature attributable to planetary-scale waves. The south-polar region has turned wintry fairly abruptly: temperature and zonal wind maps from CIRS data show that the 1-mbar temperatures at high southern latitudes in late autumn are already much colder than those at the corresponding latitudes in the north in midwinter, when the first extensive polar measurements were obtained. The south-polar region now has a strong circumpolar vortex, with maximum stratospheric winds occurring near 60° S, in contrast to the northern hemisphere in winter, where the polar vortex was much broader, extending to 20°-30° N. Potential vorticity maps now indicate steep meridional gradients at high southern latitudes, implying a barrier to efficient mixing between the polar region and lower latitudes. Radio-occultations have higher vertical resolution than CIRS, and they have recently probed latitudes as high as 65° in both hemispheres (latitudes closer to the pole are precluded because of the geometry of Earth occultations and the season). Above 80 km at these latitudes, where the radiative damping times are small enough that temperatures have large seasonal variations, the stratosphere in the north has warmed, and it has become much colder in the south. The abrupt transition region with negative vertical temperature gradient between 80 and 100 km, which was seen at high northern latitudes in winter, has weakened, but it is still visible. In the south, one can see the early stage of

  13. PREFACE: 1st Tensor Polarized Solid Target Workshop

    NASA Astrophysics Data System (ADS)

    2014-10-01

    These are the proceedings of the first Tensor Spin Observables Workshop that was held in March 2014 at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia. The conference was convened to study the physics that can be done with the recently approved E12-13-011 polarized target. A tensor polarized target holds the potential of initiating a new generation of tensor spin physics at Jefferson Lab. Experiments which utilize tensor polarized targets can help clarify how nuclear properties arise from partonic degrees of freedom, provide unique insight into short-range correlations and quark angular momentum, and also help pin down the polarization of the quark sea with a future Electron Ion Collider. This three day workshop was focused on tensor spin observables and the associated tensor target development. The workshop goals were to stimulate progress in the theoretical treatment of polarized spin-1 systems, foster the development of new proposals, and to reach a consensus on the optimal polarized target configuration for the tensor spin program. The workshop was sponsored by the University of New Hampshire, the Jefferson Science Associates, Florida International University, and Jefferson Lab. It was organized by Karl Slifer (chair), Patricia Solvignon, and Elena Long of the University of New Hampshire, Douglas Higinbotham and Christopher Keith of Jefferson Lab, and Misak Sargsian of the Florida International University. These proceedings represent the effort put forth by the community to begin exploring the possibilities that a high-luminosity, high-tensor polarized solid target can offer.

  14. Interplanetary magnetic sector polarity inferred from polar geomagnetic field observations

    NASA Technical Reports Server (NTRS)

    Eriss-Christensen, E.; Lassen, K.; Wilcox, J. M.; Gonzalez, W.; Colburn, D. S.

    1971-01-01

    With the use of a prediction technique it is shown that the polarity (toward or away from the sun) of the interplanetary magnetic field can be reliably inferred from observations of the polar geomagnetic field.

  15. Circularly polarized waves in a plasma with vacuum polarization effects

    SciTech Connect

    Lundin, J.; Stenflo, L.; Brodin, G.; Marklund, M.; Shukla, P. K.

    2007-06-15

    The theory for large amplitude circularly polarized waves propagating along an external magnetic field is extended in order to also include vacuum polarization effects. A general dispersion relation, which unites previous results, is derived.

  16. Lunar Polar Coring Lander

    NASA Technical Reports Server (NTRS)

    Angell, David; Bealmear, David; Benarroche, Patrice; Henry, Alan; Hudson, Raymond; Rivellini, Tommaso; Tolmachoff, Alex

    1990-01-01

    Plans to build a lunar base are presently being studied with a number of considerations. One of the most important considerations is qualifying the presence of water on the Moon. The existence of water on the Moon implies that future lunar settlements may be able to use this resource to produce things such as drinking water and rocket fuel. Due to the very high cost of transporting these materials to the Moon, in situ production could save billions of dollars in operating costs of the lunar base. Scientists have suggested that the polar regions of the Moon may contain some amounts of water ice in the regolith. Six possible mission scenarios are suggested which would allow lunar polar soil samples to be collected for analysis. The options presented are: remote sensing satellite, two unmanned robotic lunar coring missions (one is a sample return and one is a data return only), two combined manned and robotic polar coring missions, and one fully manned core retrieval mission. One of the combined manned and robotic missions has been singled out for detailed analysis. This mission proposes sending at least three unmanned robotic landers to the lunar pole to take core samples as deep as 15 meters. Upon successful completion of the coring operations, a manned mission would be sent to retrieve the samples and perform extensive experiments of the polar region. Man's first step in returning to the Moon is recommended to investigate the issue of lunar polar water. The potential benefits of lunar water more than warrant sending either astronauts, robots or both to the Moon before any permanent facility is constructed.

  17. Comment on "effect of a polarized hydrogen target on the polarization of a stored proton beam".

    PubMed

    MacKay, W W; Montag, C

    2006-02-01

    Meyer [Phys. Rev. E 50, 1485 (1994)] analyzed the filtering mechanism of polarizing a stored beam by scattering from an internal polarized target. We noticed in Meyer's derivation of Eq. (4) of that paper that he had added a new twist to an old argument [W. Brückner, Physics with Antiprotons at LEAR in the ACOL Era: Proceedings of the Third LEAR Workshop, Tignes, Savoie, France, January 19-26, 1985 (Editions Frontières, Gif-sur-Yvette, France, 1985), p. 245] by allowing some particles that are spin flipped to be kept in the beam. We show that this invalidates the old result and leads to a more complicated expression for the buildup of polarization. PMID:16605487

  18. Characteristics of volume polarization holography with linear polarization light

    NASA Astrophysics Data System (ADS)

    Zang, Jinliang; Wu, An'an; Liu, Ying; Wang, Jue; Lin, Xiao; Tan, Xiaodi; Shimura, Tsutomu; Kuroda, Kazuo

    2015-10-01

    Volume polarization holographic recording in phenanthrenequinone-doped poly(methyl methacrylate) (PQ-PMMA) photopolymer with linear polarized light is obtained. The characteristics of the volume polarization hologram are experimentally investigated. It is found that beyond the paraxial approximation the polarization states of the holographic reconstruction light are generally different from the signal light. Based on vector wave theoretical analyses and material properties, the special exposure condition for correctly holographic reconstruction is obtained and experimentally demonstrated.

  19. Virtually Shaping the Future of Polar Research

    NASA Astrophysics Data System (ADS)

    Baeseman, J. L.; Koldunov, N. V.; Jochum, K.

    2009-12-01

    The Association of Polar Early Career Scientists (APECS) is an international and interdisciplinary organization for undergraduate and graduate students, postdoctoral researchers, early faculty members, educators and others with interests in Polar Regions and the wider cryosphere that started as a result of the International Polar Year (IPY). APECS is leading the way for virtual communication of polar research through several activities: an online Polar Literature Discussion Forum, a Virtual Poster Session, and Communication beyond the conference setting. APECS has created an extensive online discussion forum where researchers share both classic and cutting-edge literature articles and critique techniques that were used by authors, helping to improve methods as well as discover new ways to approach polar research questions. Many researchers present their results as posters at conferences. APECS has taken this process to a new level by creating a format to display previously presented posters online instead of these files simply sitting on a researcher’s hard-drive. Not only are the posters online, a monthly conference call open to hundreds of participants allows researchers to share their work with a new audience - fellow researchers, community members, potential colleagues, policy makers and educators. These calls are recorded and archived online so the next time someone visits the poster, they can hear the researcher describe their work and communicate with the researcher questions they may have, potential ways to collaborate or share different methodologies to improve future endeavors. Peer-reviewed literature articles are the currency of science and APECS has capitalized on this by creating a way for researchers to increase the exposure of their publications beyond the table of contents published by journals. The Polar Literature Discussion Forum is a new way for researchers to share their papers, as well as discuss classic articles. This has become a popular

  20. Geomagnetic polarity transitions

    NASA Astrophysics Data System (ADS)

    Merrill, Ronald T.; McFadden, Phillip L.

    1999-05-01

    The top of Earth's liquid outer core is nearly 2900 km beneath Earth's surface, so we will never be able to observe it directly. This hot, dense, molten iron-rich body is continuously in motion and is the source of Earth's magnetic field. One of the most dynamic manifestations at Earth's surface of this fluid body is, perhaps, a reversal of the geomagnetic field. Unfortunately, the most recent polarity transition occurred at about 780 ka, so we have never observed a transition directly. It seems that a polarity transition spans many human lifetimes, so no human will ever witness the phenomenon in its entirety. Thus we are left with the tantalizing prospect that paleomagnetic records of polarity transitions may betray some of the secrets of the deep Earth. Certainly, if there are systematics in the reversal process and they can be documented, then this will reveal substantial information about the nature of the lowermost mantle and of the outer core. Despite their slowness on a human timescale, polarity transitions occur almost instantaneously on a geological timescale. This rapidity, together with limitations in the paleomagnetic recording process, prohibits a comprehensive description of any reversal transition both now and into the foreseeable future, which limits the questions that may at this stage be sensibly asked. The natural model for the geomagnetic field is a set of spherical harmonic components, and we are not able to obtain a reliable model for even the first few harmonic terms during a transition. Nevertheless, it is possible, in principle, to make statements about the harmonic character of a geomagnetic polarity transition without having a rigorous spherical harmonic description of one. For example, harmonic descriptions of recent geomagnetic polarity transitions that are purely zonal can be ruled out (a zonal harmonic does not change along a line of latitude). Gleaning information about transitions has proven to be difficult, but it does seem

  1. 77 FR 46445 - Environmental Topics Related to the International Maritime Organization's Development of a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-03

    ...The United States Coast Guard will hold a public meeting in Washington, DC on environmental topics related to the development of a mandatory code for ships operating in polar waters by the International Maritime Organization (IMO Polar...

  2. North Polar Cap

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    This week we will be looking at five examples of laminar wind flow on the north polar cap. On Earth, gravity-driven south polar cap winds are termed 'catabatic' winds. Catabatic winds begin over the smooth expanse of the cap interior due to temperature differences between the atmosphere and the surface. Once begun, the winds sweep outward along the surface of the polar cap toward the sea. As the polar surface slopes down toward sealevel, the wind speeds increase. Catabatic wind speeds in the Antartic can reach several hundreds of miles per hour.

    In the images of the Martian north polar cap we can see these same type of winds. Notice the streamers of dust moving downslope over the darker trough sides, these streamers show the laminar flow regime coming off the cap. Within the trough we see turbulent clouds of dust, kicked up at the trough base as the winds slow down and enter a chaotic flow regime.

    The horizontal lines in these images are due to framelet overlap and lighting conditions over the bright polar cap.

    Image information: VIS instrument. Latitude 86.5, Longitude 64.5 East (295.5 West). 40 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation

  3. North Polar Cap

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    This week we will be looking at five examples of laminar wind flow on the north polar cap. On Earth, gravity-driven south polar cap winds are termed 'catabatic' winds. Catabatic winds begin over the smooth expanse of the cap interior due to temperature differences between the atmosphere and the surface. Once begun, the winds sweep outward along the surface of the polar cap toward the sea. As the polar surface slopes down toward sealevel, the wind speeds increase. Catabatic wind speeds in the Antartic can reach several hundreds of miles per hour.

    In the images of the Martian north polar cap we can see these same type of winds. Notice the streamers of dust moving downslope over the darker trough sides, these streamers show the laminar flow regime coming off the cap. Within the trough we see turbulent clouds of dust, kicked up at the trough base as the winds slow down and enter a chaotic flow regime.

    The horizontal lines in these images are due to framelet overlap and lighting conditions over the bright polar cap.

    Image information:VIS instrument. Latitude 86.5, longitude 57.4 East (302.6 West). 40 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is

  4. North Polar Cap

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    This week we will be looking at five examples of laminar wind flow on the north polar cap. On Earth, gravity-driven south polar cap winds are termed 'catabatic' winds. Catabatic winds begin over the smooth expanse of the cap interior due to temperature differences between the atmosphere and the surface. Once begun, the winds sweep outward along the surface of the polar cap toward the sea. As the polar surface slopes down toward sealevel, the wind speeds increase. Catabatic wind speeds in the Antartic can reach several hundreds of miles per hour.

    In the images of the Martian north polar cap we can see these same type of winds. Notice the streamers of dust moving downslope over the darker trough sides, these streamers show the laminar flow regime coming off the cap. Within the trough we see turbulent clouds of dust, kicked up at the trough base as the winds slow down and enter a chaotic flow regime.

    The horizontal lines in these images are due to framelet overlap and lighting conditions over the bright polar cap.

    Image information: VIS instrument. Latitude 84.3, Longitude 314.4 East (45.6 West). 40 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation

  5. North Polar Cap

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    This week we will be looking at five examples of laminar wind flow on the north polar cap. On Earth, gravity-driven south polar cap winds are termed 'catabatic' winds. Catabatic winds begin over the smooth expanse of the cap interior due to temperature differences between the atmosphere and the surface. Once begun, the winds sweep outward along the surface of the polar cap toward the sea. As the polar surface slopes down toward sealevel, the wind speeds increase. Catabatic wind speeds in the Antartic can reach several hundreds of miles per hour.

    In the images of the Martian north polar cap we can see these same type of winds. Notice the streamers of dust moving downslope over the darker trough sides, these streamers show the laminar flow regime coming off the cap. Within the trough we see turbulent clouds of dust, kicked up at the trough base as the winds slow down and enter a chaotic flow regime.

    The horizontal lines in these images are due to framelet overlap and lighting conditions over the bright polar cap.

    Image information: VIS instrument. Latitude 84.2, Longitude 57.4 East (302.6 West). 40 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation

  6. Titan's Winter Polar Vortex

    NASA Technical Reports Server (NTRS)

    Flasar, F.M.; Achterberg, R.K.; Schinder, P.J.

    2008-01-01

    Titan's atmosphere has provided an interesting study in contrasts and similarities with Earth's. While both have N$_2$ as the dominant constituent and comparable surface pressures $\\sim1$ bar, Titan's next most abundant molecule is CH$_4$, not O$_2$, and the dissociative breakup of CH$_4$ and N$_2$ by sunlight and electron impact leads to a suite of hydrocarbons and nitriles, and ultimately the photochemical smog that enshrouds the moon. In addition, with a 15.95-day period, Titan is a slow rotator compared to Earth. While the mean zonal terrestrial winds are geostrophic, Titan's are mostly cyclostrophic, whipping around the moon in as little as 1 day. Despite the different dynamical regime, Titan's winter stratosphere exhibits several characteristics that should be familiar to terrestrial meteorologists. The cold winter pole near the 1 -mbar level is circumscribed by strong winds (up to 190 m/s) that act as a barrier to mixing with airmasses at lower latitudes. There is evidence of enhancement of several organic species over the winter pole, indicating subsidence. The adiabatic heating associated with this subsidence gives rise to a warm anomaly at the 0.01-mbar level, raising the stratopause two scale heights above its location at equatorial latitudes. Condensate ices have been detected in Titan's lower stratosphere within the winter polar vortex from infrared spectra. Although not always unambiguously identified, their spatial distribution exhibits a sharp gradient, decreasing precipitously across the vortex away from the winter pole. The interesting question of whether there is important heterogeneous chemistry occurring within the polar vortex, analogous to that occurring in the terrestrial polar stratospheric clouds in the ozone holes, has not been addressed. The breakup of Titan's winter polar vortex has not yet been observed. On Earth, the polar vortex is nonlinearly disrupted by interaction with large-amplitude planetary waves. Large-scale waves have not

  7. Hyperon polarization: An experimental overview

    SciTech Connect

    Lach, J.

    1992-12-01

    The fact that inclusively produced hyperons are produced with significant polarization was first discovered at Fermilab about seventeen years ago. This and subsequent experiments showed that [Lambda][degree] were produced polarized while [bar [Lambda] [degree

  8. Polarity of the Amphibian Egg

    NASA Technical Reports Server (NTRS)

    Malacinski, G. M.

    1983-01-01

    Amphibian egg polarity and the mechanism which generates the polarity is addressed. Of particular concern is the question of whether the activation rotation which responds to gravity is a prerequisite for normal development.

  9. Numerical simulation study of polar lows in Russian Arctic: dynamical characteristics

    NASA Astrophysics Data System (ADS)

    Verezemskaya, Polina; Baranyuk, Anastasia; Stepanenko, Victor

    2015-04-01

    Polar Lows (hereafter PL) are intensive mesoscale cyclones, appearing above the sea surface, usually behind the arctic front and characterized by severe weather conditions [1]. All in consequence of the global warming PLs started to emerge in the arctic water area as well - in summer and autumn. The research goal is to examine PLs by considering multisensory data and the resulting numerical mesoscale model. The main purpose was to realize which conditions induce PL development in such thermodynamically unusual season and region as Kara sea. In order to conduct the analysis we used visible and infrared images from MODIS (Aqua). Atmospheric water vapor V, cloud liquid water Q content and surface wind fields W were resampled by examining AMSR-E microwave radiometer data (Aqua)[2], the last one was additionally extracted from QuickSCAT scatterometer. We have selected some PL cases in Kara sea, appeared in autumn of 2007-2008. Life span of the PL was between 24 to 36 hours. Vortexes' characteristics were: W from 15m/s, Q and V values: 0.08-0.11 kg/m2 and 8-15 kg/m2 relatively. Numerical experiments were carried out with Weather Research and Forecasting model (WRF), which was installed on supercomputer "Lomonosov" of Research Computing Center of Moscow State University [3]. As initial conditions was used reanalysis data ERA-Interim from European Centre for Medium-Range Weather Forecasts. Numerical experiments were made with 5 km spatial resolution, with Goddard center microphysical parameterization and explicit convection simulation. Modeling fields were compared with satellite observations and shown good accordance. Than dynamic characteristics were analyzed: evolution of potential and absolute vorticity [4], surface heat and momentum fluxes, and CAPE and WISHE mechanisms realization. 1. Polar lows, J. Turner, E.A. Rasmussen, 612, Cambridge University press, Cambridge, 2003. 2. Zabolotskikh, E. V., Mitnik, L. M., & Chapron, B. (2013). New approach for severe marine

  10. X-ray polarization splitting by a single crystal evaluated with synchrotron x-rays

    SciTech Connect

    Pereira, N. R.; Presura, R.; Wallace, M.; Kastengren, A.

    2014-07-15

    In hexagonal crystals such as quartz, an asymmetric Bragg reflection from two equivalent internal crystal planes can separate unpolarized x-rays into two linearly polarized components. The perfectly polarized and tunable x-rays from a synchrotron are ideal to evaluate polarization spitting in detail. One unanticipated feature is that additional reflections from the crystal affect the diffraction intensity of the two polarized components, an effect that is unlikely to matter in polarization spectroscopy of radiating plasmas for which the crystal is intended.

  11. Polarization of a Helium-Neon Laser.

    ERIC Educational Resources Information Center

    Jones, Edwin R.

    1996-01-01

    Describes an experiment that involves measuring the intensity of laser light passed by a linear polarizer. Discusses polarization effects, orthogonal polarizations, instrumentation, and further experiments. (JRH)

  12. Polarization Perception Device

    NASA Technical Reports Server (NTRS)

    Whitehead, Victor S. (Inventor); Coulson, Kinsell L. (Inventor)

    1997-01-01

    A polarization perception device comprises a base and a polarizing filter having opposite broad sides and a centerline perpendicular thereto. The filter is mounted on the base for relative rotation and with a major portion of the area of the filter substantially unobstructed on either side. A motor on the base automatically moves the filter angularly about its centerline at a speed slow enough to permit changes in light transmission by virtue of such movement to be perceived as light-dark pulses by a human observer, but fast enough so that the light phase of each such pulse occurs prior to fading of the light phase image of the preceding pulse from the observer's retina. In addition to an observer viewing a scene in real time through the filter while it is so angularly moved, or instead of such observation, the scene can be photographed, filmed or taped by a camera whose lens is positioned behind the filter.

  13. Polarization perception device

    NASA Technical Reports Server (NTRS)

    Whitehead, Victor S. (Inventor); Coulson, Kinsel L. (Inventor)

    1992-01-01

    A polarization perception device comprises a base and a polarizing filter having opposite broad sides and a centerline perpendicular thereto. The filter is mounted on the base for relative rotation and with a major portion of the area of the filter substantially unobstructed on either side. A motor on the base automatically moves the filter angularly about its centerline at a speed slow enough to permit changes in light transmission by virtue of such movement to be perceived as light-dark pulses by a human observer, but fast enough so that the light phase of each such pulse occurs prior to fading of the light phase image of the preceding pulse from the observer's retina. In addition to an observer viewing a scene in real time through the filter while it is so angularly moved, or instead of such observation, the scene can be photographed, filmed or taped by a camera whose lens is positioned behind the filter.

  14. Galactic Diffuse Polarized Emission

    NASA Astrophysics Data System (ADS)

    Carretti, Ettore

    2011-12-01

    Diffuse polarized emission by synchrotron is a key tool to investigate magnetic fields in the Milky Way, particularly the ordered component of the large scale structure. Key observables are the synchrotron emission itself and the RM is by Faraday rotation. In this paper the main properties of the radio polarized diffuse emission and its use to investigate magnetic fields will be reviewed along with our current understanding of the galactic magnetic field and the data sets available. We will then focus on the future perspective discussing RM-synthesis - the new powerful instrument devised to unlock the information encoded in such an emission - and the surveys currently in progress like S-PASS and GMIMS.

  15. Polar Magnetic Field Data

    NASA Technical Reports Server (NTRS)

    Russell, Christopher T.; Hoffman, Robert (Technical Monitor)

    2002-01-01

    At this writing we have received all the CDROMs for the grant period. We have completed generating our timing tables past September 20, 2001. The calibration of the instrument has been checked for the entire mission up to the end of December 2000 and the key parameters provided to the project until the end of December 2000. These data are available to other experimenters over the web at http://www-ssc.igpp.ucla.edu/forms/polar/. High resolution spun data, 8 samples per see, have been created up to November, 2000 and have been made available to the community over the world wide web. This is a new data set that was a major effort this year. Our near term plans are to continue to provide key parameter data to the Polar project with the highest possible speed and to continue to reduce all high resolution magnetometer data and provide these data to the scientific community over the web.

  16. Polar vortex dynamics

    NASA Technical Reports Server (NTRS)

    Mcintyre, Michael

    1988-01-01

    Recent work with high resolution, one-layer numerical models of fluid flows resembling those in the real stratosphere has suggested that: (1) the interiors of strong cyclonic vortices like the Antarctic polar vortex may be almost completely isolated laterally from their surroundings - perhaps even completely isolated, under some circumstances; (2) by contrast, material near the edge of such and isolated region can easily be eroded (or mixed one-sidedly) into the surrounding region; and (3) the erosion characteristically produces extremely steep gradients in isentropic distributions of potential vorticity (PV) and of other tracers, possibly down to horizontal length scales of a few kilometers only. Such length scales may occur both at the edge of the main polar vortex and in smaller features outside it, such as thin filamentary structures, produced by the erosion process.

  17. The polar bear phenomena

    SciTech Connect

    Maw, P.K. ); Lane, M.T.

    1990-02-01

    Results from measuring the thermal profile of polar bear pelts, reflectiveness of the pelts, and total thermal conversion data lead to the conclusion that the pelts from an ultra-efficient thermal diode for solar-thermal conversion. The transfer of the thermal energy from the surface of the fur to the skin where it is absorbed cannot be thermal, and therefore must be radiative. This process must have an efficiency of better than 90:0090 percent to account for measured values. The radiative transfer process is not known at present. To understand it, a detailed knowledge of the microscopic parameters of the pelts must be obtained. This is the current thrust of the polar solar research. If the process can be understood and synthesized,it will provide a major breakthrough in the area of solar-thermal energy conversion.

  18. North Polar Features

    NASA Technical Reports Server (NTRS)

    2004-01-01

    28 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows banded terrain of the north polar region of Mars. The bands are exposures of layered material, possibly composed of dust and ice. The dark, rounded to elliptical mounds in this image might be the locations of ancient sand dunes that were completely buried in the north polar layered material. In more recent times, these mounds have been exhumed from within the layered material. Alternatively, the dark features are not ancient, exhumed dunes, but perhaps the remnants of a dark layer of material that once covered the entire area shown in the image. These features are located near 79.9oN, 31.4oW. The image covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

  19. South Polar Details

    NASA Technical Reports Server (NTRS)

    2005-01-01

    22 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows details among some of the eroded layer outcrops of the martian south polar region. Much of the south polar region of Mars is covered by a thick unit of layered material. For decades, the layers have been assumed to consist of a mixture of dust and ice, but it is equally possible that the materials are sedimentary rocks. This image was captured during southern spring, at a time when some of the surface was still covered by seasonal carbon dioxide (CO2) frost.

    Location near: 86.5oS, 116.6oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  20. Alternating-Polarity Arc Welding

    NASA Technical Reports Server (NTRS)

    Schwinghamer, R. J.

    1987-01-01

    Brief reversing polarity of welding current greatly improves quality of welds. NASA technical memorandum recounts progress in art of variable-polarity plasma-arc (VPPA) welding, with emphasis on welding of aluminum-alloy tanks. VPPA welders offer important advantages over conventional single-polarity gas/tungsten arc welders.

  1. Polarized Emissivity and Kirchhoff's law.

    PubMed

    Resnick, A; Persons, C; Lindquist, G

    1999-03-10

    An expression for the polarized emissivity of a material is obtained with the Stokes vector-Mueller matrix polarization formalism. The result obtained is that thermally emitted radiance might have a circular polarization component. In addition, the emissivity depends only on the reflectance matrix. PMID:18305757

  2. Animated Displays IV: Linear Polarization.

    ERIC Educational Resources Information Center

    Chagnon, Paul

    1993-01-01

    Describes several demonstrations that can be easily reproduced to help students understand optical polarization. Displays and supplement text include polarization by reflection; polarization by scattering; liquid crystals; optical activity; calcite; birefringent plastics; retardation plates; photoelasticity; and the "Optical Barber Pole." Contains…

  3. Cryogenic, polar lunar observatories

    NASA Technical Reports Server (NTRS)

    Burke, J. D.

    1988-01-01

    In a geological vein, it is noted that some permanently shadowed regions on the Moon could provide natural passive cooling environments for astronomical detectors. A telescope located in one of the low, dark, polar regions could operate with only passive cooling at 40 K or perhaps lower, depending on how well it could be insulated from the ground and surrounded by radiation shields to block heat and light from any nearby warm or illuminated objects.

  4. Polarized advanced fuel reactors

    SciTech Connect

    Kulsrud, R.M.

    1987-07-01

    The d-/sup 3/He reaction has the same spin dependence as the d-t reaction. It produces no neutrons, so that if the d-d reactivity could be reduced, it would lead to a neutron-lean reactor. The current understanding of the possible suppression of the d-d reactivity by spin polarization is discussed. The question as to whether a suppression is possible is still unresolved. Other advanced fuel reactions are briefly discussed. 11 refs.

  5. Polarization induced doped transistor

    DOEpatents

    Xing, Huili; Jena, Debdeep; Nomoto, Kazuki; Song, Bo; Zhu, Mingda; Hu, Zongyang

    2016-06-07

    A nitride-based field effect transistor (FET) comprises a compositionally graded and polarization induced doped p-layer underlying at least one gate contact and a compositionally graded and doped n-channel underlying a source contact. The n-channel is converted from the p-layer to the n-channel by ion implantation, a buffer underlies the doped p-layer and the n-channel, and a drain underlies the buffer.

  6. Martian polar geological studies

    NASA Technical Reports Server (NTRS)

    Cutts, J. A. J.

    1977-01-01

    Multiple arcs of rugged mountains and adjacent plains on the surface of Mars were examined. These features, located in the southern polar region were photographed by Mariner 9. Comparisons are made with characteristics of a lunar basin and mare; Mare imbrium in particular. The martian feature is interpreted to have originated in the same way as its lunar analog- by volcanic flooding of a large impact basin. Key data and methodology leading to this conclusion are cited.

  7. PEPPo: Using a Polarized Electron Beam to Produce Polarized Positrons

    SciTech Connect

    Adeyemi, Adeleke H.

    2015-09-01

    Polarized positron beams have been identified as either an essential or a significant ingredient for the experimental program of both the present and next generation of lepton accelerators (JLab, Super KEK B, ILC, CLIC). An experiment demonstrating a new method for producing polarized positrons has been performed at the Continuous Electron Beam Accelerator Facility at Jefferson Lab. The PEPPo (Polarized Electrons for Polarized Positrons) concept relies on the production of polarized e⁻/e⁺ pairs from the bremsstrahlung radiation of a longitudinally polarized electron beam interacting within a high-Z conversion target. PEPPo demonstrated the effective transfer of spin-polarization of an 8.2 MeV/c polarized (P~85%) electron beam to positrons produced in varying thickness tungsten production targets, and collected and measured in the range of 3.1 to 6.2 MeV/c. In comparison to other methods this technique reveals a new pathway for producing either high-energy or thermal polarized positron beams using a relatively low polarized electron beam energy (~10MeV) .This presentation will describe the PEPPo concept, the motivations of the experiment and high positron polarization achieved.

  8. Synchrotron polarization in blazars

    SciTech Connect

    Zhang, Haocheng; Böttcher, Markus; Chen, Xuhui

    2014-07-01

    We present a detailed analysis of time- and energy-dependent synchrotron polarization signatures in a shock-in-jet model for γ-ray blazars. Our calculations employ a full three-dimensional radiation transfer code, assuming a helical magnetic field throughout the jet. The code considers synchrotron emission from an ordered magnetic field, and takes into account all light-travel-time and other relevant geometric effects, while the relevant synchrotron self-Compton and external Compton effects are handled with the two-dimensional Monte-Carlo/Fokker-Planck (MCFP) code. We consider several possible mechanisms through which a relativistic shock propagating through the jet may affect the jet plasma to produce a synchrotron and high-energy flare. Most plausibly, the shock is expected to lead to a compression of the magnetic field, increasing the toroidal field component and thereby changing the direction of the magnetic field in the region affected by the shock. We find that such a scenario leads to correlated synchrotron + synchrotron-self-Compton flaring, associated with substantial variability in the synchrotron polarization percentage and position angle. Most importantly, this scenario naturally explains large polarization angle rotations by ≳ 180°, as observed in connection with γ-ray flares in several blazars, without the need for bent or helical jet trajectories or other nonaxisymmetric jet features.

  9. Understanding ultracold polar molecules

    NASA Astrophysics Data System (ADS)

    Julienne, Paul

    2009-05-01

    The successful production of a dense sample of ultracold ground state KRb polar molecules [1] opens the door to a new era of research with dipolar gases and lattices of such species. This feat was achieved by first associating a K and a Rb atom to make a weakly bound Feshbach molecule and then coherently transferring the population to the ground vibrational level of the molecule. This talk focuses on theoretical issues associated with making and using ultracold polar molecules, using KRb as an example [2]. Full understanding of this species and the processes by which it is made requires taking advantage of accurate molecular potentials [3], ab initio calculations [4], and the properties of the long-range potential. A highly accurate model is available for KRb for all bound states below the ground state separated atom limit and could be constructed for other species. The next step is to develop an understanding of the interactions between polar molecules, and their control in the ultracold domain. Understanding long-range interactions and threshold resonances will be crucial for future work. [1] K.-K. Ni, et al, Science 322, 231(2008). [2] P. S. Julienne, arXiv:0812:1233. [3] Pashov et al., Phys. Rev. A76, 022511 (2007). [4] S. Kotochigova, et al., arXiv:0901.1486.

  10. Pliocene geomagnetic polarity epochs

    USGS Publications Warehouse

    Dalrymple, G.B.; Cox, A.; Doell, Richard R.; Gromme, C.S.

    1967-01-01

    A paleomagnetic and K-Ar dating study of 44 upper Miocene and Pliocene volcanic units from the western United States suggests that the frequency of reversals of the earth's magnetic field during Pliocene time may have been comparable with that of the last 3.6 m.y. Although the data are too limited to permit the formal naming of any new polarity epochs or events, four polarity transitions have been identified: the W10 R/N boundary at 3.7 ?? 0.1 m.y., the A12 N/R boundary at 4.9 ?? 0.1 m.y., the W32 N/R boundary at 9.0 ?? 0.2m.y., and the W36 R/N boundary at 10.8 ?? 0.3 - 1.0 m.y. The loss of absolute resolution of K-Ar dating in older rocks indicates that the use of well defined stratigraphic successions to identify and date polarity transitions will be important in the study of Pliocene and older reversals. ?? 1967.

  11. Synchrotron Polarization in Blazars

    NASA Astrophysics Data System (ADS)

    Zhang, Haocheng; Chen, Xuhui; Böttcher, Markus

    2014-07-01

    We present a detailed analysis of time- and energy-dependent synchrotron polarization signatures in a shock-in-jet model for γ-ray blazars. Our calculations employ a full three-dimensional radiation transfer code, assuming a helical magnetic field throughout the jet. The code considers synchrotron emission from an ordered magnetic field, and takes into account all light-travel-time and other relevant geometric effects, while the relevant synchrotron self-Compton and external Compton effects are handled with the two-dimensional Monte-Carlo/Fokker-Planck (MCFP) code. We consider several possible mechanisms through which a relativistic shock propagating through the jet may affect the jet plasma to produce a synchrotron and high-energy flare. Most plausibly, the shock is expected to lead to a compression of the magnetic field, increasing the toroidal field component and thereby changing the direction of the magnetic field in the region affected by the shock. We find that such a scenario leads to correlated synchrotron + synchrotron-self-Compton flaring, associated with substantial variability in the synchrotron polarization percentage and position angle. Most importantly, this scenario naturally explains large polarization angle rotations by >~ 180°, as observed in connection with γ-ray flares in several blazars, without the need for bent or helical jet trajectories or other nonaxisymmetric jet features.

  12. Antarctica Day: An International Celebration

    NASA Astrophysics Data System (ADS)

    Pope, A.; Hambrook Berkman, J.; Berkman, P. A.

    2013-12-01

    For more than half a century, the 1959 Antarctic Treaty continues to shine as a rare beacon of international cooperation. To celebrate this milestone of peace in our civilization with hope and inspiration for future generations, Antarctica Day is celebrated each year on December 1st , the anniversary of the Antarctic Treaty signing. As an annual event - initiated by the Foundation for the Good Governance of International Spaces (www.internationalspaces.org/) in collaboration with the Association of Polar Early Carer Scientists (www.apecs.is) - Antarctica Day encourages participation from around the world. The Antarctic Treaty set aside 10% of the earth, 'forever to be used exclusively for peaceful purposes in the interest of mankind.' It was the first nuclear arms agreement and the first institution to govern all human activities in an international region beyond sovereign jurisdictions. In this spirit, Antarctica Day aims to: - Demonstrate how diverse nations can work together peacefully, using science as a global language of cooperation for decision making beyond national boundaries, - Provide strategies for students learning about Antarctica through art, science and history at all school levels, - Increase collaboration and communication between classrooms, communities, researchers and government officials around the world, and - Provide a focus for polar educators to build on each year. Through close collaboration with a number of partners. Antarctica Day activities have included: a Polar Film Festival convened by The Explorers Club; live sessions connecting classrooms with scientists in Antarctica thanks to PolarTREC and ARCUS; an international activity that involved children from 13 countries who created over 600 flags which exemplify Antarctica Day (these were actually flown in Antarctica with signed certificates then returned to the classes); a map where Antarctica Day participants all over the world could share what they were doing; an Antarctic bird count

  13. An airborne system for collecting polarization imagery

    NASA Technical Reports Server (NTRS)

    Hildum, Edward A.; Spinhirne, James D.

    1992-01-01

    This paper describes a recently completed electrooptical camera flying onboard the NASA ER-2 high altitude aircraft. The device includes a six-position filter wheel which can be fitted with a combination of polarizing and/or spectral filters. An alternate configuration will include a polarizing filter which can be rotated to any angle under computer control. The camera mount in the nose of the ER-2 can tilt forward or aft up to 40 degrees, both for bidirectional reflectance studies and for image motion compensation (the aircraft moves 34 meters between frame acquisitions). The ground resolution is nominally 5 meters from and altitude of 20 km. Spectral responsivity is that of the silicon imaging array (Kodak KAF-1400). Initial data sets were acquired in support of the International Satellite Cloud Climatology Program Regional Experiment of November, 1991, and will be used to study cirrus cloud properties.

  14. Predictability of the earth's polar motion

    NASA Technical Reports Server (NTRS)

    Fong, B.

    1985-01-01

    The results of a numerical experiment on the predictability of terrestrial polar motion using a Bureau International de l'Heure data set from 1967-83 are presented. A floating point predictor was defined by decomposing polar motion into secular motion and annual and Chandler wobbles. The secular term was linear and the others periodic, the former due to atmospheric mass transport and the latter to Eulerian nutation. A least squares estimator was employed with the data base to obtain constants for the model, which is given the name 'floating-point'. A fixed-period predictor was also devised and, in comparison with the floating point predictor in 6 yr estimates of the annual wobble period, failed after a given length of time. It is suggested that the failure is due to atmospheric motions.

  15. Polarization of metastable 129Xe

    NASA Astrophysics Data System (ADS)

    Xia, Tian; Morgan, Steven; Jau, Yuan-Yu; Happer, William

    2008-05-01

    We have measured atomic polarization of metastable 129Xe in a pyrex cell by optical pumping, while metastability exchange optical pumping of 3He is routinely done. The atomic polarization of metastable Xe is on the order of 10%. Metastable xenon is created by electrodeless rf discharge. The hyperfine transition of metastable 129Xe is observed by microwave excitation. Atomic polarization can be demonstrated by comparison of the intensities of the transitions between different Zeeman sublevels, while pumping a specific optical transition of metastable Xe with circularly polarized light. This work offers insight into attempts to polarize 129Xe nuclei by metastability exchange optical pumping.

  16. Device For Perception Of Polarization

    NASA Technical Reports Server (NTRS)

    Whitehead, Victor S.; Coulson, Kinsel

    1993-01-01

    Polarized image viewed through rotating polarizing filter appears to pulsate. Optical device enables human observer to perceive polarization of light. Used alone for viewing in real time and/or in conjunction with video or movie camera to record for subsequent detailed quantitative analysis of polarization in scene. Device used in remote sensing to classify portions of scenes according to polarization characteristics, to enhance viewing through atmosphere and oceans and to enhance contrasts. Used to monitor oilspill from air and detect changes in soil moisture and to map wetlands, among many other possible civilian and military applications.

  17. Towards Polarized Antiprotons at FAIR

    SciTech Connect

    Rathmann, Frank

    2007-06-13

    Understanding the interplay of the nuclear interaction with polarized protons and the electromagnetic interaction with polarized electrons in polarized atoms is crucial to progress towards the PAX goal to eventually produce stored polarized antiproton beams at FAIR. Presently, there exist two competing theoretical scenarios: one with substantial spin filtering of (anti)protons by atomic electrons, and a second one suggesting a self-cancellation of the electron contribution to spin filtering. After a brief review of the PAX physics case for polarized antiprotons at FAIR, a detailed discussion of future investigations, including spin-filtering experiments at COSY-Juelich and at the AD of CERN is presented.

  18. Sensitivity of VIIRS Polarization Measurements

    NASA Technical Reports Server (NTRS)

    Waluschka, Eugene

    2010-01-01

    The design of an optical system typically involves a sensitivity analysis where the various lens parameters, such as lens spacing and curvatures, to name two parameters, are (slightly) varied to see what, if any, effect this has on the performance and to establish manufacturing tolerances. A sinular analysis was performed for the VIIRS instruments polarization measurements to see how real world departures from perfectly linearly polarized light entering VIIRS effects the polarization measurement. The methodology and a few of the results of this polarization sensitivity analysis are presented and applied to the construction of a single polarizer which will cover the VIIRS VIS/NIR spectral range. Keywords: VIIRS, polarization, ray, trace; polarizers, Bolder Vision, MOXTEK

  19. Z-pinch X-ray spectra obtained with a polarization splitting crystal

    NASA Astrophysics Data System (ADS)

    Presura, R.; Wallace, M. S.; Pereira, N. R.

    2014-10-01

    Anisotropy in a plasma may cause polarization of the spectral lines emitted. For example, the X-rays emitted by Z-pinch plasmas may be polarized if electron beams are present. To detect the polarization, we developed an X-ray spectropolarimeter using a single polarization-splitting crystal. Reflections on intersecting internal planes of the crystal select lines with mutually orthogonal linear polarization. The (10-10) internal planes of a quartz crystal can be used to split several lines of the Al K-shell spectrum according to polarization. We applied this technique to several types of Al wire arrays (cylindrical, conical, and X-pinches), expected to produce increasing beam contributions to the electron population. Peculiarities of the instrument set-up and of the spectra analysis will be presented. This work was supported by DOE, NNSA Grant DE-NA0001834 and cooperative Agreement DE-FC52-06NA27616.

  20. International Youth Conference on the Poles

    NASA Astrophysics Data System (ADS)

    Church, A. K.; Kuhn, T. S.; Baeseman, J.; Garmulewicz, A.; Raymond, M.; Salmon, R.

    2006-12-01

    The International Polar Year (IPY) is an international effort, involving more than 50 countries, to focus research in both the sciences and social sciences on the world's Polar Regions. In order to secure youth involvement in the IPY, the Youth Steering Committee (YSC) has been formed, aiming specifically to network young polar researchers from all backgrounds enabling collaboration and to involve this group in outreach focused towards other young people. A conference targeted directly at an audience of early career researchers and international youth will be central to fulfilling these aims. The YSC has therefore developed the concept of the International Youth Conference on the Poles (IYCP). Proposed for 2008, this conference will bring together youth from a diverse set of backgrounds and nationalities to discuss the issues affecting the Polar Regions, their effects on a global scale and ways of addressing these issues. The conference will also serve to highlight ongoing IPY research, especially research being undertaken by young researchers, and provide a perennial framework for youth involvement in polar research and policies. The IYCP will run for three days in May 2008, attracting an international youth audience, as well as representatives from polar organizations, teachers, politicians, policy makers, the general public and media. The IYCP will be divided into three sections. Youth Roundtable Discussions will bring youth together to discuss issues affecting the Polar Regions and potential solutions to these. A Young Researchers Conference will provide the opportunity for young researchers working in the Polar Regions to present their work to an interdisciplinary audience. The Polar Fair will provide an interactive environment for youth to learn about the Polar Regions. The IYCP will be of great importance to the IPY because it will serve as the principle venue during the Polar Year where youth from many different disciplines, backgrounds and countries will

  1. Investigation of major international and Turkish companies via hierarchical methods and bootstrap approach

    NASA Astrophysics Data System (ADS)

    Kantar, E.; Deviren, B.; Keskin, M.

    2011-11-01

    We present a study, within the scope of econophysics, of the hierarchical structure of 98 among the largest international companies including 18 among the largest Turkish companies, namely Banks, Automobile, Software-hardware, Telecommunication Services, Energy and the Oil-Gas sectors, viewed as a network of interacting companies. We analyze the daily time series data of the Boerse-Frankfurt and Istanbul Stock Exchange. We examine the topological properties among the companies over the period 2006-2010 by using the concept of hierarchical structure methods (the minimal spanning tree (MST) and the hierarchical tree (HT)). The period is divided into three subperiods, namely 2006-2007, 2008 which was the year of global economic crisis, and 2009-2010, in order to test various time-windows and observe temporal evolution. We carry out bootstrap analyses to associate the value of statistical reliability to the links of the MSTs and HTs. We also use average linkage clustering analysis (ALCA) in order to better observe the cluster structure. From these studies, we find that the interactions among the Banks/Energy sectors and the other sectors were reduced after the global economic crisis; hence the effects of the Banks and Energy sectors on the correlations of all companies were decreased. Telecommunication Services were also greatly affected by the crisis. We also observed that the Automobile and Banks sectors, including Turkish companies as well as some companies from the USA, Japan and Germany were strongly correlated with each other in all periods.

  2. Katabatic jumps over Martian polar terrains

    NASA Astrophysics Data System (ADS)

    Spiga, Aymeric; Smith, Isaac; Holt, Jack

    2015-04-01

    with an horizontal morphology similar to trough clouds, strong ascending motions at the jump reaching 1.5 m/s (a significantly large value in the stable polar atmosphere), and temperature perturbations propitious to cloud formation. Mesoscale modeling suggests here that trough clouds are present manifestation of the ice migration that yielded the internal cap structure discovered by radar observations, as part of a "cyclic step" process. This has important implications for the stability and possible migration over geological timescales of water ice surface reservoirs.

  3. A Clifford Algebra Description of Polarization Optics

    NASA Astrophysics Data System (ADS)

    Yevick, David; Soliman, George

    2014-03-01

    The polarization changes induced by optical components are represented as Clifford algebra transformations. This yields a unified formalism for polarized and partially polarized light and for the frequency dependence of polarization in the presence of polarization mode dispersion and polarization dependent loss. Work supported by NSERC.

  4. South Polar Polygons

    NASA Technical Reports Server (NTRS)

    2005-01-01

    4 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a polgyon-cracked surface, into which deep, somewhat kidney-bean-shaped pits have formed. These are landscapes of the martian south polar residual cap. This view was captured during May 2005.

    Location near: 86.9oS, 5.1oW Image width: 1.5 km (0.9 mi) Illumination from: upper left Season Southern Spring

  5. South Polar Scene

    NASA Technical Reports Server (NTRS)

    2004-01-01

    5 February 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of the south polar residual cap. Sunlight illuminates this scene from the upper left, thus the somewhat kidney bean-shaped features are pits, not mounds. These pits and their neighboring polygonal cracks are formed in a material composed mostly of carbon dioxide ice. The image is located near 87.0oS, 5.7oW, and covers an area 3 km (1.9 mi) wide.

  6. Gluon polarization in nucleon

    NASA Astrophysics Data System (ADS)

    Shahveh, Abolfazl; Taghavi-Shahri, Fatemeh; Arash, Firooz

    2010-07-01

    In the context of the so-called valon model, we calculate δg/g and show that although it is small and compatible with the measured values, the gluon contribution to the spin of nucleon can be sizable. The smallness of δg/g in the measured kinematical region should not be interpreted as δg being small. In fact, δg itself at small x, and the first moment of the polarized gluon distribution in the nucleon, Δg (Q2), are large.

  7. 'Endurance' Untouched (polar)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This navigation camera mosaic, created from images taken by NASA's Mars Exploration Rover Opportunity on sols 115 and 116 (May 21 and 22, 2004) provides a dramatic view of 'Endurance Crater.' The rover engineering team carefully plotted the safest path into the football field-sized crater, eventually easing the rover down the slopes around sol 130 (June 12, 2004). To the upper left of the crater sits the rover's protective heatshield, which sheltered Opportunity as it passed through the martian atmosphere. The 360-degree view is presented in a polar projection, with geometric and radiometric seam correction.

  8. North Polar Dunes

    NASA Technical Reports Server (NTRS)

    2005-01-01

    10 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows low-albedo sand dunes in the north polar region. The slip faces on the dunes face toward the lower left, indicating that the dominant winds in this region blow or blew from the upper right.

    Location near: 82.4oN, 46.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Summer

  9. South Polar Erosion

    NASA Technical Reports Server (NTRS)

    2004-01-01

    24 June 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the results of erosion acting upon a layer of material in the south polar region of Mars. The elliptical pit in the lower left corner of the image was once buried beneath this eroding layer, as well. The processes that eroded the material, and the composition of the material, are unknown. The image is located near 80.7oS, 300.9oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates this scene from the top.

  10. South Polar Depression

    NASA Technical Reports Server (NTRS)

    2005-01-01

    14 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a circular depression and a suite of eroding mesas of carbon dioxide. These features occur in the south polar residual cap of Mars. The eroding carbon dioxide creates landforms reminiscent of 'Swiss cheese.' The circular feature might indicate the location of a filled, buried impact crater.

    Location near: 86.8oS, 111.0oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  11. On the charge polarization of cosmic systems

    NASA Technical Reports Server (NTRS)

    Barnes, A.

    1979-01-01

    The positive electric charge density associated with the internal electric fields of self-gravitating systems in hydrostatic equilibrium can be canceled by nearby external flowing plasmas, such as winds. For example, it can be shown that the positive electric charge of a star is likely to be completely screened by its stellar wind. Because winds and other nonstatic phenomena are widespread, the electrical polarization due to the positive charge on static systems such as stars should occur on relatively local scales, in contrast to the universal scale recently suggested by Bally and Harrison. The latter viewpoint would be correct only if the entire universe were in strict hydrostatic equilibrium.

  12. INFLUENCE OF THE POLAR CAP CURRENT ON PULSAR POLARIZATION

    SciTech Connect

    Kumar, D.; Gangadhara, R. T. E-mail: ganga@iiap.res.in

    2012-07-20

    We have developed a model for the polarization of curvature radiation by taking into account the polar-cap-current-induced perturbation on the dipolar magnetic field. We present the effects of the polar cap current on the pulsar radio emission in an artificial case when the rotation effects, such as aberration and retardation, are absent. Our model indicates that the intensity components and the polarization angle inflection point can be shifted to either the leading or the trailing side depending upon the prevailing conditions in the viewing geometry, the non-uniformity in source distribution (modulation), and the polar-cap-current-induced perturbation. Also, we find evidence for the origin of symmetric-type circular polarization in addition to the antisymmetric type. Our model predicts a stronger trailing component compared to that on the leading side of a given cone under some specific conditions.

  13. Efficient and broadband polarization conversion with the coupled metasurfaces.

    PubMed

    Huang, Cheng-ping

    2015-12-14

    Coupled metasurfaces may refer to a composite plasmonic structure, which consists of multilayered but usually different metasurfaces. A pair of orthogonal plasmonic polarizers, which represents one of such systems, can induce a transmission of light and 90-degree polarization rotation. We explored the effect systematically and found that such effect may be highly efficient and broadband in the near-infrared region. By combining the low-loss metal (silver), the longer operating wavelength, and a work style using propagating waveguide mode, conversion efficiency more than 80% has been suggested near the telecom wavelength. We also suggested that, by overlapping the internal surface-plasmon (2, 0) and (1, 1) modes, an efficient and wideband polarization rotation can be realized. The maximal efficiency is 83% around the wavelength 1340 nm, and the working bandwidth reaches 300 nm. Similar effect has also been revealed in the THz band. The results are useful for constructing compact and high-performance polarization rotators. PMID:26698992

  14. SCATTERING POLARIZATION IN SOLAR FLARES

    SciTech Connect

    Štěpán, Jiří; Heinzel, Petr

    2013-11-20

    There is ongoing debate about the origin and even the very existence of a high degree of linear polarization of some chromospheric spectral lines observed in solar flares. The standard explanation of these measurements is in terms of the impact polarization caused by non-thermal proton and/or electron beams. In this work, we study the possible role of resonance line polarization due to radiation anisotropy in the inhomogeneous medium of the flare ribbons. We consider a simple two-dimensional model of the flaring chromosphere and we self-consistently solve the non-LTE problem taking into account the role of resonant scattering polarization and of the Hanle effect. Our calculations show that the horizontal plasma inhomogeneities at the boundary of the flare ribbons can lead to a significant radiation anisotropy in the line formation region and, consequently, to a fractional linear polarization of the emergent radiation of the order of several percent. Neglecting the effects of impact polarization, our model can provide a clue for resolving some of the common observational findings, namely: (1) why a high degree of polarization appears mainly at the edges of the flare ribbons; (2) why polarization can also be observed during the gradual phase of a flare; and (3) why polarization is mostly radial or tangential. We conclude that radiation transfer in realistic multi-dimensional models of solar flares needs to be considered as an essential ingredient for understanding the observed spectral line polarization.

  15. Spin-polarized Hartree-Fock approximation at nonzero temperatures

    NASA Astrophysics Data System (ADS)

    Hong, Suklyun; Mahan, G. D.

    1995-06-01

    The Hartree-Fock exchange energy is calculated for the spin-polarized electron gas at nonzero temperatures. This calculation is done self-consistently in that the Hartree-Fock self-energy is included self-consistently in the Fermi-Dirac occupation numbers while performing a coupling constant integral. The internal energy and entropy are also considered. We calculate the first and second derivatives of the exchange energy, internal energy, and entropy with respect to number density and/or spin polarization density, which are used for calculations of response functions such as the compressibility and polarization. One should have in mind that our exchange-only scheme using the coupling-constant-integral formalism is different from the usual Hartree-Fock approximation at nonzero temperatures and is indeed its self-consistent generalization.

  16. Recent developments in stored polarized electron positron beams

    NASA Astrophysics Data System (ADS)

    Rossmanith, R.

    1992-01-01

    In nearly all electron or positron storage rings the beams are polarized vertically by the Sokolov-Ternov effect. The existence of polarized beams was established both in low energy rings such as ACO (the first storage ring in which the Sokolov-Ternov polarization effect was measured), BESSY, and VEPP2 and in high energy rings such as TRISTAN, HERA, and LEP. As a result beam polarization seems to be an inherent property of electron-positron rings. It should be noted that this free polarization was never used for high energy experiments except in those instances in which exact energy calibration measurements were performed. Proposals for using stored polarized beams for internal target experiments are fairly new. Experiments with polarized longitudinal beams in LEP are still in the stage of planning. The efforts of the last few years are summarized in order to arrive at a better understanding of the spin dynamics in electron positron storage rings and to compare the experimental results with the theory. Polarimeters are not discussed.

  17. Central neural coding of sky polarization in insects.

    PubMed

    Homberg, Uwe; Heinze, Stanley; Pfeiffer, Keram; Kinoshita, Michiyo; el Jundi, Basil

    2011-03-12

    Many animals rely on a sun compass for spatial orientation and long-range navigation. In addition to the Sun, insects also exploit the polarization pattern and chromatic gradient of the sky for estimating navigational directions. Analysis of polarization-vision pathways in locusts and crickets has shed first light on brain areas involved in sky compass orientation. Detection of sky polarization relies on specialized photoreceptor cells in a small dorsal rim area of the compound eye. Brain areas involved in polarization processing include parts of the lamina, medulla and lobula of the optic lobe and, in the central brain, the anterior optic tubercle, the lateral accessory lobe and the central complex. In the optic lobe, polarization sensitivity and contrast are enhanced through convergence and opponency. In the anterior optic tubercle, polarized-light signals are integrated with information on the chromatic contrast of the sky. Tubercle neurons combine responses to the UV/green contrast and e-vector orientation of the sky and compensate for diurnal changes of the celestial polarization pattern associated with changes in solar elevation. In the central complex, a topographic representation of e-vector tunings underlies the columnar organization and suggests that this brain area serves as an internal compass coding for spatial directions. PMID:21282171

  18. Tissue morphodynamics: Translating planar polarity cues into polarized cell behaviors.

    PubMed

    Devenport, Danelle

    2016-07-01

    The ability of cells to collectively orient and align their behaviors is essential in multicellular organisms for unidirectional cilia beating, collective cell movements, oriented cell divisions, and asymmetric cell fate specification. The planar cell polarity pathway coordinates a vast and diverse array of collective cell behaviors by intersecting with downstream pathways that regulate cytoskeletal dynamics and intercellular signaling. How the planar polarity pathway translates directional cues to produce polarized cell behaviors is the focus of this review. PMID:26994528

  19. Polar Rain Gradients and Field-Aligned Polar Cap Potentials

    NASA Technical Reports Server (NTRS)

    Fairfield, D. H.; Wing, S.; Newell, P. T.; Ruohoniemi, J. M.; Gosling, J. T.; Skoug, R. M.

    2008-01-01

    ACE SWEPAM measurements of solar wind field-aligned electrons have been compared with simultaneous measurements of polar rain electrons precipitating over the polar cap and detected by DMSP spacecraft. Such comparisons allow investigation of cross-polarcap gradients in the intensity of otherwise-steady polar rain. The generally good agreement of the distribution functions, f, from the two data sources confirms that direct entry of solar electrons along open field lines is indeed the cause of polar rain. The agreement between the data sets is typically best on the side of the polar cap with most intense polar rain but the DMSP f's in less intense regions can be brought into agreement with ACE measurements by shifting all energies by a fixed amounts that range from tens to several hundred eV. In most cases these shifts are positive which implies that field-aligned potentials of these amounts exist on polar cap field lines which tend to retard the entry of electrons and produce the observed gradients. These retarding potentials undoubtedly appear in order to prevent the entry of low-energy electrons and maintain charge quasi-neutrality that would otherwise be violated since most tailward flowing magnetosheath ions are unable to follow polar rain electrons down to the polar cap. In more limited regions near the boundary of the polar cap there is sometimes evidence for field-aligned potentials of the opposite sign that accelerate polar rain electrons. A solar electron burst is also studied and it is concluded that electrons from such bursts can enter the magnetotail and precipitate in the same manner as polar rain.

  20. Experiments with Fermilab polarized proton and polarized antiproton beams

    SciTech Connect

    Yokosawa, A.

    1990-01-01

    We summarize activities concerning the Fermilab polarized beams. They include a brief description of the polarized-beam facility, measurements of beam polarization by polarimeters, asymmetry measurements in the {pi}{degree} production at high p{sub {perpendicular}} and in the {Lambda} ({Sigma}{degree}), {pi}{sup {plus minus}}, {pi}{degree} production at large x{sub F}, and {Delta}{sigma}{sub L}(pp, {bar p}p) measurements. 18 refs.