Science.gov

Sample records for abrupt presidential departure

  1. Presidential Transition: The Experience of Two Community College Interim Presidents

    ERIC Educational Resources Information Center

    Thompson, Matthew D.

    2010-01-01

    The purpose of this qualitative case study was to understand the experiences of two community college interim presidents, their characteristics, and how they led institutions following an abrupt presidential departure. There were two fundamental questions framing this research study, 1. How do two interim community college presidents lead…

  2. Presidential Evaluation.

    ERIC Educational Resources Information Center

    Williams, Ruthann E.

    The interest in and need for presidential evaluation has arisen from the increased size and complexity of institutions, the call for accountability, the increasing difficulty of the presidential task, and the shift in roles and responsibilities of the presidency. Presidential evaluation provides an institution with the opportunity to delineate…

  3. Presidential Sweepstakes.

    ERIC Educational Resources Information Center

    Doyle, Denis P.

    1996-01-01

    Ponders Americans' disenchantment with politics. Presents essays outlining presidential candidates Bill Clinton's and Bob Dole's plans for education. Clinton/Gore campaigners stress the President's achievements (expanding Head Start) and plans to encourage charter schools, fight truancy, and increase college access. Decrying Clinton's friendship…

  4. Introduction. Presidential disability and presidential succession.

    PubMed

    Gilbert, Robert E; Bucy, Erik P

    2014-01-01

    This introduction to the special issue on presidential disability and succession focuses on the distinctly positive contributions that invocations of the Twenty-Fifth Amendment have made to American political life since the Amendment's ratification in 1967. It also underlines the importance for Presidents, their family members and aides to understand the necessity for putting the welfare of the country first, above all else-even at times above the wishes of a disabled Chief Executive. As the articles in this special issue make clear, the Twenty-Fifth Amendment provides an effective constitutional mechanism by which the country's well-being can be maintained while simultaneously showing compassion and respect for a disabled leader. The idea for this issue emerged from a conference organized by Professor Robert E. Gilbert focusing on presidential disability and succession held on the campus of Northeastern University in April 2014. Papers from the conference assembled here clarify and add to the historical record about presidential inability while illuminating the many political, legal, and constitutional contingencies that future presidential administrators may face. Contributors to this issue have varied disciplinary and professional backgrounds, including expertise in American politics, constitutional law, the presidency and vice presidency, presidential impairment, and, of course, the Twenty-Fifth Amendment to the Constitution.

  5. Teaching Presidential Impeachment.

    ERIC Educational Resources Information Center

    Luckowski, Jean A.; Lopach, James J.

    1999-01-01

    Believes that by teaching presidential impeachment through an issues-centered approach, students will discover key political values, the ambiguities in legal documents, the clash of power sources, and an appreciation of legal norms. Offers a lesson on teaching presidential impeachment through the use of a student debate. (CMK)

  6. Pregnancy Complications: Placental Abruption

    MedlinePlus

    ... page It's been added to your dashboard . The placenta attaches to the wall of the uterus (womb) ... abruption is a serious condition in which the placenta separates from the wall of the uterus before ...

  7. "Ruralizing" Presidential Job Advertisements

    ERIC Educational Resources Information Center

    Leist, Jay

    2007-01-01

    Rural community college presidential job advertisements that focus on geography, politics, and culture can improve the likelihood of a good fit between the senior leader and the institution. (Contains 2 figures.)

  8. Presidential Events: Chicago

    NASA Astrophysics Data System (ADS)

    Walworth, Frank

    2007-03-01

    Catherine T. ("Katie") Hunt, ACS President 2007, will cosponsor a full week of presidential events and sessions. In her desire to work together to address substantive societal issues, she has selected Sustainability of Energy, Food, and Water as the presidential theme for this meeting. The goal is to successfully execute meaningful thematic programming at national meetings that will not only nucleate ideas, foster community, and accelerate innovation, but be essential to effectively communicate chemistry to a broader audience. Open discussions as a scientific community will better enable us to speak with one voice to our membership, the media, and the general public.

  9. [The Presidential Libraries.

    ERIC Educational Resources Information Center

    Webb, John

    There are seven Presidential libraries in various states of existence, from quite active to proposed: (1) Franklin D. Roosevelt Library, (2) Harry S. Truman Library, (3) Herbert Hoover Library, (4) Dwight D. Eisenhower Library, (5) John F. Kennedy Memorial Library (6) Lyndon B. Johnson Library and (7) Rutherford B. Hayes Memorial Library. Each…

  10. Before Departure: Advising Tropical Travellers

    PubMed Central

    Russell, Margaret

    1990-01-01

    Advising travellers to tropical and subtropical countries before their departure requires physician use of regularly updated information sources. The author outlines an approach to risk assessment and presents an overview of important issues and some information sources. PMID:21233911

  11. 11 CFR 9002.10 - Presidential election.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Presidential election. 9002.10 Section 9002.10 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: GENERAL ELECTION FINANCING DEFINITIONS § 9002.10 Presidential election. Presidential election means the election...

  12. 11 CFR 9002.10 - Presidential election.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 11 Federal Elections 1 2011-01-01 2011-01-01 false Presidential election. 9002.10 Section 9002.10 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: GENERAL ELECTION FINANCING DEFINITIONS § 9002.10 Presidential election. Presidential election means the election...

  13. 11 CFR 9002.10 - Presidential election.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 11 Federal Elections 1 2014-01-01 2014-01-01 false Presidential election. 9002.10 Section 9002.10 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: GENERAL ELECTION FINANCING DEFINITIONS § 9002.10 Presidential election. Presidential election means the election...

  14. 11 CFR 9002.10 - Presidential election.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 11 Federal Elections 1 2012-01-01 2012-01-01 false Presidential election. 9002.10 Section 9002.10 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: GENERAL ELECTION FINANCING DEFINITIONS § 9002.10 Presidential election. Presidential election means the election...

  15. 11 CFR 9002.10 - Presidential election.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 11 Federal Elections 1 2013-01-01 2012-01-01 true Presidential election. 9002.10 Section 9002.10 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: GENERAL ELECTION FINANCING DEFINITIONS § 9002.10 Presidential election. Presidential election means the election...

  16. Presidential Pay: Not Exactly Lavish.

    ERIC Educational Resources Information Center

    Manley, Frank

    1984-01-01

    The 1984 Compensation and Benefits Survey of College and University Chief Executive Officers is discussed. The survey provides information on presidential compensation, benefits, and employment practices at public, independent, religious, and medical institutions. (MLW)

  17. Presidential Leaks: Rhetoric and Mediated Political Knowledge.

    ERIC Educational Resources Information Center

    Erickson, Keith V.

    1989-01-01

    Argues that presidential leaks constitute rhetorical acts, enabling administrations to exercise a variety of rhetorically potent options not afforded by the public forum. Proposes a typology of presidential leaks and analyzes their rhetorical functions, benefits, and liabilities. (MM)

  18. 36 CFR 1253.3 - Presidential Libraries.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the Presidential libraries' research rooms are posted at http://www.archives.gov. The Presidential...) Lyndon Baines Johnson Library and Museum is located at 2313 Red River St., Austin, TX 78705-5702....

  19. Surface Management System Departure Event Data Analysis

    NASA Technical Reports Server (NTRS)

    Monroe, Gilena A.

    2010-01-01

    This paper presents a data analysis of the Surface Management System (SMS) performance of departure events, including push-back and runway departure events.The paper focuses on the detection performance, or the ability to detect departure events, as well as the prediction performance of SMS. The results detail a modest overall detection performance of push-back events and a significantly high overall detection performance of runway departure events. The overall detection performance of SMS for push-back events is approximately 55%.The overall detection performance of SMS for runway departure events nears 100%. This paper also presents the overall SMS prediction performance for runway departure events as well as the timeliness of the Aircraft Situation Display for Industry data source for SMS predictions.

  20. 36 CFR 1253.3 - Presidential Libraries.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Presidential Libraries. 1253... PUBLIC AVAILABILITY AND USE LOCATION OF RECORDS AND HOURS OF USE § 1253.3 Presidential Libraries. The Presidential libraries are open for research from 9 a.m. to 5 p.m., Monday through Friday, except...

  1. 14 CFR 294.51 - Presidential review.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Presidential review. 294.51 Section 294.51... REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Cancellation of Registration and Presidential Review § 294.51 Presidential review. A Department order under § 294.50 (e), (g) or (i) shall be subject to stay or...

  2. The Arctic Grand Challenge: Abrupt Climate Change

    NASA Astrophysics Data System (ADS)

    Wilkniss, P. E.

    2003-12-01

    Trouble in polar paradise (Science, 08/30/02), significant changes in the Arctic environment are scientifically documented (R.E. Moritz et al. ibid.). More trouble, lots more, "abrupt climate change," (R. B. Alley, et al. Science 03/28/03). R. Corell, Arctic Climate Impact Assessment team (ACIA), "If you want to see what will happen in the rest of the world 25 years from now just look what's happening in the Arctic," (Arctic Council meeting, Iceland, 08/03). What to do? Make abrupt Arctic climate change a grand challenge for the IPY-4 and beyond! Scientifically:Describe the "state" of the Arctic climate system as succinctly as possible and accept it as the point of departure.Develop a hypothesis and criteria what constitutes "abrupt climate change," in the Arctic that can be tested with observations. Observations: Bring to bear existing observations and coordinate new investments in observations through an IPY-4 scientific management committee. Make the new Barrow, Alaska, Global Climate Change Research Facility a major U.S. contribution and focal point for the IPY-4 in the U.S Arctic. Arctic populations, Native peoples: The people of the North are living already, daily, with wrenching change, encroaching on their habitats and cultures. For them "the earth is faster now," (I. Krupnik and D. Jolly, ARCUS, 2002). From a political, economic, social and entirely realistic perspective, an Arctic grand challenge without the total integration of the Native peoples in this effort cannot succeed. Therefore: Communications must be established, and the respective Native entities must be approached with the determination to create well founded, well functioning, enduring partnerships. In the U.S. Arctic, Barrow with its long history of involvement and active support of science and with the new global climate change research facility should be the focal point of choice Private industry: Resource extraction in the Arctic followed by oil and gas consumption, return the combustion

  3. Presidential Survival in Tough Times.

    ERIC Educational Resources Information Center

    Bowen, Raymond C.

    Surviving the position of college president requires the development of a presidential survival kit filled with idiosyncratic items not normally associated with formal educational training. Strength, agility, control, and the ability to improvise are some of the talents required of a college president. In addition, the longevity and success of a…

  4. 49 CFR 236.587 - Departure test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...: (1) Operation over track elements; (2) Operation over test circuit; (3) Use of portable test... 49 Transportation 4 2011-10-01 2011-10-01 false Departure test. 236.587 Section 236.587..., Train Control and Cab Signal Systems Inspection and Tests; Locomotive § 236.587 Departure test. (a)...

  5. 49 CFR 236.587 - Departure test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Departure test. 236.587 Section 236.587..., Train Control and Cab Signal Systems Inspection and Tests; Locomotive § 236.587 Departure test. (a) The...: (1) Operation over track elements; (2) Operation over test circuit; (3) Use of portable...

  6. Implementation Issues for Departure Planning Systems

    NASA Technical Reports Server (NTRS)

    Hansman, R. John; Feron, Eric; Clarke, John-Paul; Odoni, Amedeo

    1999-01-01

    The objective of the proposed effort is to investigate issues associated with the design and implementation of decision aiding tools to assist in improving the departure process at congested airports. This effort follows a preliminary investigation of potential Departure Planning approaches and strategies, which identified potential benefits in departure efficiency, and also in reducing the environmental impact of aircraft in the departure queue. The preliminary study bas based, in large part, on observations and analysis of departure processes at Boston, Logan airport. The objective of this follow-on effort is to address key implementation issues and to expand the observational base to include airports with different constraints and traffic demand. Specifically, the objectives of this research are to: (1) Expand the observational base to include airports with different underlying operational dynamics. (2) Develop prototype decision aiding algorithms/approaches and assess potential benefits. and (3) Investigate Human Machine Integration (HMI) issues associated with decision aids in tower environments.

  7. Spot and Runway Departure Advisor

    NASA Technical Reports Server (NTRS)

    Jung, Yoon Chul

    2013-01-01

    The Spot and Runway Departure Advisor (SARDA) is a research prototype of a decision support tool for ATC tower controllers to assist in manging and controlling traffic on the surface of an airport. SARDA employs a scheduler to generate an optimal runway schedule and gate push-back - spot release sequence and schedule that improves efficiency of surface operations. The advisories for ATC tower controllers are displayed on an Electronic Flight Strip (EFS) system. The human-in-the-loop simulation of the SARDA tool was conducted for east operations of Dallas-Ft. Worth International Airport (DFW) to evaluate performance of the SARDA tool and human factors, such as situational awareness and workload. The results indicates noticeable taxi delay reduction and fuel savings by using the SARDA tool. Reduction in controller workload were also observed throughout the scenario runs. The future plan includes modeling and simulation of the ramp operations of the Charlotte International Airport, and develop a decision support tool for the ramp controllers.

  8. Analysis of abrupt transitions in ecological systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The occurrence and causes of abrupt transitions, thresholds, or regime shifts between ecosystem states are of great concern and the likelihood of such transitions is increasing for many ecological systems. General understanding of abrupt transitions has been advanced by theory, but hindered by the l...

  9. Presidential Debates: Not a Spectator Sport.

    ERIC Educational Resources Information Center

    Social Education, 2000

    2000-01-01

    Provides two teaching activities to help students analyze political debates from a curriculum for middle and high schools called "Presidential Debates: A Teacher's Guide". Designed by the Commission on Presidential Debates and Kids Voting USA, it includes : (1) "The Techniques of Persuasion"; and (2) "It's Your Turn to be a Political Reporter."…

  10. Newsmagazine Visuals and the 1988 Presidential Election.

    ERIC Educational Resources Information Center

    Moriarty, Sandra; Popovich, Mark

    A study examined newsmagazines' visual coverage of the 1988 election to determine if patterns of difference in the visual presentation of candidates existed. A content analysis examined all the visuals (photographs and illustrations) of the presidential and vice-presidential candidates printed in three national weekly newsmagazines--"U.S. News and…

  11. The Role and Function of Presidential Libraries.

    ERIC Educational Resources Information Center

    Fischer, Linda

    This paper identifies various elements of presidential libraries. The advantages and disadvantages of the libraries' centralization or decentralization are discussed, and some common misconceptions held by the public as to the role and function of presidential libraries are identified. Criticism and debate from the professional community about…

  12. Presidential Guideline Series, Vol. 1-6

    ERIC Educational Resources Information Center

    Council for Higher Education Accreditation, 2007

    2007-01-01

    The Council for Higher Education Accreditation "Presidential Guidelines Series" was developed during 2006-2007 as means to further engage presidents in the work of accreditation and to offer tools for presidential leadership in this important area. Six individual Guidelines were issued, each addressing a vital dimension of the president…

  13. Symposium on Presidential Libraries and Materials.

    ERIC Educational Resources Information Center

    Thompson, Brian Chandler; And Others

    1995-01-01

    Collection of nine articles about presidential libraries. Highlights include the National Archives; the Bush Presidential Materials Project; the Nixon Project; automation of the Lyndon B. Johnson Library; the John F. Kennedy Library; the Eisenhower Library's four decades; past and future of the Harry S. Truman Library; the Franklin D. Roosevelt…

  14. 46 CFR 565.11 - Presidential review.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 9 2014-10-01 2014-10-01 false Presidential review. 565.11 Section 565.11 Shipping FEDERAL MARITIME COMMISSION REGULATIONS AND ACTIONS TO ADDRESS RESTRICTIVE FOREIGN MARITIME PRACTICES CONTROLLED CARRIERS § 565.11 Presidential review. The Commission shall transmit all orders of suspension...

  15. 46 CFR 565.11 - Presidential review.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 9 2011-10-01 2011-10-01 false Presidential review. 565.11 Section 565.11 Shipping FEDERAL MARITIME COMMISSION REGULATIONS AND ACTIONS TO ADDRESS RESTRICTIVE FOREIGN MARITIME PRACTICES CONTROLLED CARRIERS § 565.11 Presidential review. The Commission shall transmit all orders of suspension...

  16. Precision Departure Release Capability (PDRC) Final Report

    NASA Technical Reports Server (NTRS)

    Engelland, Shawn A.; Capps, Richard; Day, Kevin Brian; Kistler, Matthew Stephen; Gaither, Frank; Juro, Greg

    2013-01-01

    After takeoff, aircraft must merge into en route (Center) airspace traffic flows that may be subject to constraints that create localized demand/capacity imbalances. When demand exceeds capacity, Traffic Management Coordinators (TMCs) and Frontline Managers (FLMs) often use tactical departure scheduling to manage the flow of departures into the constrained Center traffic flow. Tactical departure scheduling usually involves a Call for Release (CFR) procedure wherein the Tower must call the Center to coordinate a release time prior to allowing the flight to depart. In present-day operations release times are computed by the Center Traffic Management Advisor (TMA) decision support tool, based upon manual estimates of aircraft ready time verbally communicated from the Tower to the Center. The TMA-computed release time is verbally communicated from the Center back to the Tower where it is relayed to the Local controller as a release window that is typically three minutes wide. The Local controller will manage the departure to meet the coordinated release time window. Manual ready time prediction and verbal release time coordination are labor intensive and prone to inaccuracy. Also, use of release time windows adds uncertainty to the tactical departure process. Analysis of more than one million flights from January 2011 indicates that a significant number of tactically scheduled aircraft missed their en route slot due to ready time prediction uncertainty. Uncertainty in ready time estimates may result in missed opportunities to merge into constrained en route flows and lead to lost throughput. Next Generation Air Transportation System plans call for development of Tower automation systems capable of computing surface trajectory-based ready time estimates. NASA has developed the Precision Departure Release Capability (PDRC) concept that improves tactical departure scheduling by automatically communicating surface trajectory-based ready time predictions and departure

  17. Can ice sheets trigger abrupt climatic change?

    SciTech Connect

    Hughes, T.

    1996-11-01

    The discovery in recent years of abrupt climatic changes in climate proxy records from Greenland ice cores and North Atlantic sediment cores, and from other sites around the world, has diverted attention from gradual insolation changes caused by Earth`s orbital variations to more rapid processes on Earth`s surface as forcing Quaternary climatic change. In particular, forcing by ice sheets has been quantified for a major ice stream that drained the Laurentide Ice Sheet along Hudson Strait. The history of these recent discoveries leading to an interest in ice sheets is reviewed, and a case is made that ice sheets may drive abrupt climatic change that is virtually synchronous worldwide. Attention is focused on abrupt inception and termination of a Quaternary glaciation cycle, abrupt changes recorded as stadials and interstadials within the cycle, abrupt changes in ice streams that trigger stadials and interstadials, and abrupt changes in the Laurentide Ice Sheet linked to effectively simultaneous abrupt changes in its ice streams. Remaining work needed to quantify further these changes is discussed. 90 refs., 14 figs.

  18. Spot and Runway Departure Advisor (SARDA)

    NASA Technical Reports Server (NTRS)

    Jung, Yoon

    2016-01-01

    Spot and Runway Departure Advisor (SARDA) is a decision support tool to assist airline ramp controllers and ATC tower controllers to manage traffic on the airport surface to significantly improve efficiency and predictability in surface operations. The core function of the tool is the runway scheduler which generates an optimal solution for runway sequence and schedule of departure aircraft, which would minimize system delay and maximize runway throughput. The presentation also discusses the latest status of NASA's current surface research through a collaboration with an airline partner, where a tool is developed for airline ramp operators to assist departure pushback operations. The presentation describes the concept of the SARDA tool and results from human-in-the-loop simulations conducted in 2012 for Dallas-Ft. Worth International Airport and 2014 for Charlotte airport ramp tower.

  19. Departure Trajectory Synthesis and the Intercept Problem

    NASA Technical Reports Server (NTRS)

    Bolender, Michael A.; Slater, G. L.

    1997-01-01

    Two areas of the departure problem in air traffic control are discussed. The first topic is the generation of climb-out trajectories to a fix. The trajectories would be utilized by a scheduling algorithm to allocate runways, sequence the proposed departures, and assign a departure time. The second area is concerned with finding horizontal trajectories to merge aircraft from the TRACON to an open slot in the en-route environment. Solutions are presented for the intercept problem for two cases: (1) the aircraft is traveling at the speed of the aircraft in the jetway; (2) the merging aircraft has to accelerate to reach the speed of the aircraft in the en-route stream. An algorithm is given regarding the computation of a solution for the latter case. For the former, a set of equations is given that allows us to numerically solve for the coordinate where the merge will occur.

  20. 78 FR 46402 - Issuance of a Presidential Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-31

    ... of a Presidential Permit July 18, 2013. AGENCY: Department of State. ACTION: Notice of Issuance of a Presidential Permit for Vantage Pipeline US LP. SUMMARY: The Department of State issued a Presidential Permit... related to the Department of State's review of the application for a Presidential Permit can be found...

  1. 26 CFR 701.9006-1 - Presidential Election Campaign Fund.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 20 2014-04-01 2014-04-01 false Presidential Election Campaign Fund. 701.9006-1...) INTERNAL REVENUE PRACTICE PRESIDENTIAL ELECTION CAMPAIGN FUND § 701.9006-1 Presidential Election Campaign Fund. (a) Transfer of amounts to the Presidential Election Campaign Fund. The Secretary shall...

  2. 26 CFR 701.9006-1 - Presidential Election Campaign Fund.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 20 2012-04-01 2012-04-01 false Presidential Election Campaign Fund. 701.9006-1...) INTERNAL REVENUE PRACTICE PRESIDENTIAL ELECTION CAMPAIGN FUND § 701.9006-1 Presidential Election Campaign Fund. (a) Transfer of amounts to the Presidential Election Campaign Fund. The Secretary shall...

  3. 26 CFR 701.9006-1 - Presidential Election Campaign Fund.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 20 2011-04-01 2011-04-01 false Presidential Election Campaign Fund. 701.9006-1...) INTERNAL REVENUE PRACTICE PRESIDENTIAL ELECTION CAMPAIGN FUND § 701.9006-1 Presidential Election Campaign Fund. (a) Transfer of amounts to the Presidential Election Campaign Fund. The Secretary shall...

  4. 26 CFR 701.9006-1 - Presidential Election Campaign Fund.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... been transferred to the Presidential Election Campaign Fund under § 701.9006-1(a). (e) Limit on... 26 Internal Revenue 20 2010-04-01 2010-04-01 false Presidential Election Campaign Fund. 701.9006-1...) INTERNAL REVENUE PRACTICE PRESIDENTIAL ELECTION CAMPAIGN FUND § 701.9006-1 Presidential Election...

  5. Precision Departure Release Capability (PDRC) Technology Description

    NASA Technical Reports Server (NTRS)

    Engelland, Shawn A.; Capps, Richard; Day, Kevin; Robinson, Corissia; Null, Jody R.

    2013-01-01

    After takeoff, aircraft must merge into en route (Center) airspace traffic flows which may be subject to constraints that create localized demand-capacity imbalances. When demand exceeds capacity, Traffic Management Coordinators (TMCs) often use tactical departure scheduling to manage the flow of departures into the constrained Center traffic flow. Tactical departure scheduling usually involves use of a Call for Release (CFR) procedure wherein the Tower must call the Center TMC to coordinate a release time prior to allowing the flight to depart. In present-day operations release times are computed by the Center Traffic Management Advisor (TMA) decision support tool based upon manual estimates of aircraft ready time verbally communicated from the Tower to the Center. The TMA-computed release is verbally communicated from the Center back to the Tower where it is relayed to the Local controller as a release window that is typically three minutes wide. The Local controller will manage the departure to meet the coordinated release time window. Manual ready time prediction and verbal release time coordination are labor intensive and prone to inaccuracy. Also, use of release time windows adds uncertainty to the tactical departure process. Analysis of more than one million flights from January 2011 indicates that a significant number of tactically scheduled aircraft missed their en route slot due to ready time prediction uncertainty. Uncertainty in ready time estimates may result in missed opportunities to merge into constrained en route flows and lead to lost throughput. Next Generation Air Transportation System (NextGen) plans call for development of Tower automation systems capable of computing surface trajectory-based ready time estimates. NASA has developed the Precision Departure Release Capability (PDRC) concept that uses this technology to improve tactical departure scheduling by automatically communicating surface trajectory-based ready time predictions to the

  6. Abrupt climate change and extinction events

    NASA Technical Reports Server (NTRS)

    Crowley, Thomas J.

    1988-01-01

    There is a growing body of theoretical and empirical support for the concept of instabilities in the climate system, and indications that abrupt climate change may in some cases contribute to abrupt extinctions. Theoretical indications of instabilities can be found in a broad spectrum of climate models (energy balance models, a thermohaline model of deep-water circulation, atmospheric general circulation models, and coupled ocean-atmosphere models). Abrupt transitions can be of several types and affect the environment in different ways. There is increasing evidence for abrupt climate change in the geologic record and involves both interglacial-glacial scale transitions and the longer-term evolution of climate over the last 100 million years. Records from the Cenozoic clearly show that the long-term trend is characterized by numerous abrupt steps where the system appears to be rapidly moving to a new equilibrium state. The long-term trend probably is due to changes associated with plate tectonic processes, but the abrupt steps most likely reflect instabilities in the climate system as the slowly changing boundary conditions caused the climate to reach some threshold critical point. A more detailed analysis of abrupt steps comes from high-resolution studies of glacial-interglacial fluctuations in the Pleistocene. Comparison of climate transitions with the extinction record indicates that many climate and biotic transitions coincide. The Cretaceous-Tertiary extinction is not a candidate for an extinction event due to instabilities in the climate system. It is quite possible that more detailed comparisons and analysis will indicate some flaws in the climate instability-extinction hypothesis, but at present it appears to be a viable candidate as an alternate mechanism for causing abrupt environmental changes and extinctions.

  7. 49 CFR 236.587 - Departure test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... performing the test. These records shall be retained for at least 92 days. [49 FR 3387, Jan. 26, 1984, as amended at 53 FR 37313, Sept. 26, 1988] Effective Date Note: At 49 FR 3387, Jan. 26, 1984, § 236.587 was... 49 Transportation 4 2014-10-01 2014-10-01 false Departure test. 236.587 Section...

  8. 49 CFR 236.587 - Departure test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Departure test. 236.587 Section 236.587... performing the test. These records shall be retained for at least 92 days. Effective Date Note: At 49 FR 3387, Jan. 26, 1984, § 236.587 was revised. This section contains information collection and...

  9. An Event Model of Student Departure.

    ERIC Educational Resources Information Center

    DesJardins, S. L.; Ahlburg, D. A.; McCall, B. P.

    1999-01-01

    Employs event-history modeling to examine temporal dimensions of student departure from a large research university. Asian students are less likely to depart in year 1 than Whites. African-Americans are more likely to leave during junior and senior years. Dynamic models may presage sound dropout-intervention strategies. (54 references) (MLH)

  10. 20 CFR 655.35 - Required departure.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Required departure. 655.35 Section 655.35 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR TEMPORARY EMPLOYMENT OF FOREIGN WORKERS IN THE UNITED STATES Labor Certification Process and Enforcement of Attestations for Temporary Employment in Occupations Other...

  11. Seven Democratic Presidential Candidates Debate Educational Issues.

    ERIC Educational Resources Information Center

    Equity and Excellence, 1988

    1988-01-01

    Provides the transcript of a debate on educational issues among Democratic presidential candidates Paul Simon, Albert Gore, Joseph Biden, Jesse Jackson, Bruce Babbitt, Richard Gephart, and Michael Dukakis. (BJV)

  12. 36 CFR 1253.3 - Presidential Libraries.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... Hours for the Presidential libraries' research rooms are posted at http://www.archives.gov. The...) Lyndon Baines Johnson Library and Museum is located at 2313 Red River St., Austin, TX 78705-5702....

  13. 36 CFR 1253.3 - Presidential Libraries.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... Hours for the Presidential libraries' research rooms are posted at http://www.archives.gov. The...) Lyndon Baines Johnson Library and Museum is located at 2313 Red River St., Austin, TX 78705-5702....

  14. 36 CFR 1253.3 - Presidential Libraries.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... Hours for the Presidential libraries' research rooms are posted at http://www.archives.gov. The...) Lyndon Baines Johnson Library and Museum is located at 2313 Red River St., Austin, TX 78705-5702....

  15. Monsoon abrupt change and its dominant factors

    NASA Astrophysics Data System (ADS)

    Yao, Qiang; Fu, Conbin

    2010-05-01

    Abrupt changes of monsoon are apparent in the geological record of climate over various timescales. During Holocene and last glacial period, rainfall in India and China has undergone strong and abrupt changes. In this context, we regard monsoon as dissipative system, which has many characteristic times, to contrive various factors and corresponding mechanism dominated in monsoon's abrupt change. The abrupt change of monsoon over inter-decadal to century timescales may be resulting from different fluctuation's competition, which impose on the inner basic physic processes. In order to find out the key factors which control the monsoon's abrupt change, starting from the seminar works by Leith, who proposed to employ the Fluctuation-dissipation Response theory(FDR) to study the response of climatic systems to changes in the external forcing, many authors applied this relation to different geophysical problems, ranging from simplified models to general circulation models and to the covariance of satellite radiance spectra. The FDR has been originally developed in the framework of statistical mechanics of Hamiltonian systems, nevertheless a generalized FDR holds under rather general hypotheses, regardless of the Hamiltonian, or equilibrium nature of the system. Our work verify the FDR theory' applicability in monsoon systems, which demonstrates that it can reveal clear and fundamental factors that control monsoon's abrupt change. By making use of FDR theory, combined with observational data analysis, we have already seen how monsoon systems with many characteristics times, different correlation functions behave differently and a variety of timescales emerges, which correspond to the different decay times of the correlation functions. Via theoretical and data analysis, it is suggested that each monsoon system has experienced several significant abrupt changes in 20th century. The global main monsoon rainfall has undergone an obvious abrupt jump in the mid- and late 1970s

  16. Abrupt Impacts of Climate Change: Anticipating Surprises

    NASA Astrophysics Data System (ADS)

    White, James W. C.; Alley, Richard B.; Archer, David E.; Barnosky, Anthony D.; Dunlea, Edward; Foley, Jonathan; Fu, Rong; Holland, Marika M.; Lozier, M. Susan; Schmitt, Johanna; Smith, Laurence C.; Sugihara, George; Thompson, David W. J.; Weaver, Andrew J.; Wofsy, Steven C.

    2014-05-01

    Levels of carbon dioxide and other greenhouse gases in Earth's atmosphere are exceeding levels recorded in the past millions of years, and thus climate is being forced beyond the range of the recent geological era. Lacking concerted action by the world's nations, it is clear that the future climate will be warmer, sea levels will rise, global rainfall patterns will change, and ecosystems will be altered. However, there is still uncertainty about how we will arrive at that future climate state. Although many projections of future climatic conditions have predicted steadily changing conditions giving the impression that communities have time to gradually adapt, the scientific community has been paying increasing attention to the possibility that at least some changes will be abrupt, perhaps crossing a threshold or "tipping point" to change so quickly that there will be little time to react. This presentation will synopsize the new US National Research Council Report, Abrupt Impacts of Climate Change: Anticipating Surprises, highlighting areas of increased and decreased concern, as well as areas of new concern. Emphasis is placed on not only abrupt change in physical climate, but on abrupt changes in human and natural systems that can occur as a result of a slowly changing climate. The report calls for action now on an abrupt change early warning system (ACEWS) if societies are to be resilient to climate change.

  17. 75 FR 27767 - Application To Rescind Presidential Permit; Joint Application for Presidential Permit; Fraser...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-18

    ... making facility in Madawaska, Maine with their paper pulp facility in Edmundston, New Brunswick, Canada... Application To Rescind Presidential Permit; Joint Application for Presidential Permit; Fraser Papers Inc. and Twin Rivers Paper Company Inc. AGENCY: Office of Electricity Delivery and Energy Reliability,...

  18. 76 FR 70765 - Advisory Committee on Presidential Library-Foundation Partnerships

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-15

    ... RECORDS ADMINISTRATION Advisory Committee on Presidential Library-Foundation Partnerships AGENCY: National... (NARA) announces a meeting of the Advisory Committee on Presidential Library-Foundation Partnerships... Presidential Libraries, program activities at the Presidential Libraries, and the status of the...

  19. The economics of abrupt climate change.

    PubMed

    Perrings, Charles

    2003-09-15

    The US National Research Council defines abrupt climate change as a change of state that is sufficiently rapid and sufficiently widespread in its effects that economies are unprepared or incapable of adapting. This may be too restrictive a definition, but abrupt climate change does have implications for the choice between the main response options: mitigation (which reduces the risks of climate change) and adaptation (which reduces the costs of climate change). The paper argues that by (i) increasing the costs of change and the potential growth of consumption, and (ii) reducing the time to change, abrupt climate change favours mitigation over adaptation. Furthermore, because the implications of change are fundamentally uncertain and potentially very high, it favours a precautionary approach in which mitigation buys time for learning. Adaptation-oriented decision tools, such as scenario planning, are inappropriate in these circumstances. Hence learning implies the use of probabilistic models that include socioeconomic feedbacks.

  20. Abrupt climate change: can society cope?

    PubMed

    Hulme, Mike

    2003-09-15

    Consideration of abrupt climate change has generally been incorporated neither in analyses of climate-change impacts nor in the design of climate adaptation strategies. Yet the possibility of abrupt climate change triggered by human perturbation of the climate system is used to support the position of both those who urge stronger and earlier mitigative action than is currently being contemplated and those who argue that the unknowns in the Earth system are too large to justify such early action. This paper explores the question of abrupt climate change in terms of its potential implications for society, focusing on the UK and northwest Europe in particular. The nature of abrupt climate change and the different ways in which it has been defined and perceived are examined. Using the example of the collapse of the thermohaline circulation (THC), the suggested implications for society of abrupt climate change are reviewed; previous work has been largely speculative and has generally considered the implications only from economic and ecological perspectives. Some observations about the implications from a more social and behavioural science perspective are made. If abrupt climate change simply implies changes in the occurrence or intensity of extreme weather events, or an accelerated unidirectional change in climate, the design of adaptation to climate change can proceed within the existing paradigm, with appropriate adjustments. Limits to adaptation in some sectors or regions may be reached, and the costs of appropriate adaptive behaviour may be large, but strategy can develop on the basis of a predicted long-term unidirectional change in climate. It would be more challenging, however, if abrupt climate change implied a directional change in climate, as, for example, may well occur in northwest Europe following a collapse of the THC. There are two fundamental problems for society associated with such an outcome: first, the future changes in climate currently being

  1. Abrupt climate change: can society cope?

    PubMed

    Hulme, Mike

    2003-09-15

    Consideration of abrupt climate change has generally been incorporated neither in analyses of climate-change impacts nor in the design of climate adaptation strategies. Yet the possibility of abrupt climate change triggered by human perturbation of the climate system is used to support the position of both those who urge stronger and earlier mitigative action than is currently being contemplated and those who argue that the unknowns in the Earth system are too large to justify such early action. This paper explores the question of abrupt climate change in terms of its potential implications for society, focusing on the UK and northwest Europe in particular. The nature of abrupt climate change and the different ways in which it has been defined and perceived are examined. Using the example of the collapse of the thermohaline circulation (THC), the suggested implications for society of abrupt climate change are reviewed; previous work has been largely speculative and has generally considered the implications only from economic and ecological perspectives. Some observations about the implications from a more social and behavioural science perspective are made. If abrupt climate change simply implies changes in the occurrence or intensity of extreme weather events, or an accelerated unidirectional change in climate, the design of adaptation to climate change can proceed within the existing paradigm, with appropriate adjustments. Limits to adaptation in some sectors or regions may be reached, and the costs of appropriate adaptive behaviour may be large, but strategy can develop on the basis of a predicted long-term unidirectional change in climate. It would be more challenging, however, if abrupt climate change implied a directional change in climate, as, for example, may well occur in northwest Europe following a collapse of the THC. There are two fundamental problems for society associated with such an outcome: first, the future changes in climate currently being

  2. 8 CFR 1215.2 - Authority of departure-control officer to prevent alien's departure from the United States.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... departure-control officer who knows or has reason to believe that the case of an alien in the United States... temporarily preventing his departure from the United States, he shall be notified in writing concerning the... being removed from the United States upon, or in connection with, the alien's departure.......

  3. 8 CFR 1215.2 - Authority of departure-control officer to prevent alien's departure from the United States.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... departure-control officer who knows or has reason to believe that the case of an alien in the United States... temporarily preventing his departure from the United States, he shall be notified in writing concerning the... being removed from the United States upon, or in connection with, the alien's departure.......

  4. 8 CFR 1215.2 - Authority of departure-control officer to prevent alien's departure from the United States.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... departure-control officer who knows or has reason to believe that the case of an alien in the United States... temporarily preventing his departure from the United States, he shall be notified in writing concerning the... being removed from the United States upon, or in connection with, the alien's departure.......

  5. 8 CFR 1215.2 - Authority of departure-control officer to prevent alien's departure from the United States.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... departure-control officer who knows or has reason to believe that the case of an alien in the United States... temporarily preventing his departure from the United States, he shall be notified in writing concerning the... being removed from the United States upon, or in connection with, the alien's departure.......

  6. 8 CFR 1215.2 - Authority of departure-control officer to prevent alien's departure from the United States.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... departure-control officer who knows or has reason to believe that the case of an alien in the United States... temporarily preventing his departure from the United States, he shall be notified in writing concerning the... being removed from the United States upon, or in connection with, the alien's departure.......

  7. Pre-departure preparation for international clinical work: a handbook.

    PubMed

    Edwardson, Jill; Owens, Lauren; Moran, Dane; Aluri, James; Kironji, Antony; Chen, Chi Chiung Grace

    2015-08-01

    International clinical experiences are increasingly popular among medical students, residents, fellows, and practitioners. Adequate pre-departure training is an integral part of a meaningful, productive, and safe international experience. At Johns Hopkins University School of Medicine, we have developed a pre-departure handbook to assist practitioners in preparing for global health work. The handbook draws from current global health education literature, existing handbooks, and expert experiences, and includes information about logistical and cultural preparations. While a pre-departure handbook cannot serve as a substitute for a comprehensive pre-departure training program, it can be a useful introduction to the pre-departure process.

  8. Pre-departure preparation for international clinical work: a handbook.

    PubMed

    Edwardson, Jill; Owens, Lauren; Moran, Dane; Aluri, James; Kironji, Antony; Chen, Chi Chiung Grace

    2015-08-01

    International clinical experiences are increasingly popular among medical students, residents, fellows, and practitioners. Adequate pre-departure training is an integral part of a meaningful, productive, and safe international experience. At Johns Hopkins University School of Medicine, we have developed a pre-departure handbook to assist practitioners in preparing for global health work. The handbook draws from current global health education literature, existing handbooks, and expert experiences, and includes information about logistical and cultural preparations. While a pre-departure handbook cannot serve as a substitute for a comprehensive pre-departure training program, it can be a useful introduction to the pre-departure process. PMID:25994626

  9. Asteroid mission departure strategies from a precessing Space Station orbit

    NASA Technical Reports Server (NTRS)

    Sharma, Jayant

    1990-01-01

    In using the Space Station as a point of departure for interplanetary missions, the precission of its orbit complicates the process of determining the available departure period. The constantly changing ascending node of the Space Station orbit defines the departure geometry. Severe Delta V penalties occur if favorable departure opportunities are missed and a plane change is required at departure. This paper compares two strategies to reduce the cost of the plane change maneuver, and increase the available departure opportunities. A 3-impulse injection strategy is compared to a deep space plane change for two asteroid rendezvous missions. Results indicate that the deep space plane change strategy has lower propellant mass requirements for the two missions studied. The difference in propellant requirements for the two strategies is a function of the departure geometry.

  10. 76 FR 35918 - Nixon Presidential Historical Materials; Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-20

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials; Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of Opening of Additional Materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  11. 77 FR 58179 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-19

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration ACTION: Notice of opening of additional materials SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  12. 75 FR 68384 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-05

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of Opening of Additional Materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  13. 77 FR 31400 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-25

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of Opening of Additional Materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  14. 76 FR 62856 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of opening of additional materials. SUMMARY: This notice announces the opening of Nixon Presidential Historical Materials by the Richard Nixon...

  15. 75 FR 30863 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-02

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of opening of additional materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  16. 76 FR 27092 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-10

    ... RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of opening of additional materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials by the Richard...

  17. Abrupt tropical climate change: Past and present

    PubMed Central

    Thompson, Lonnie G.; Mosley-Thompson, Ellen; Brecher, Henry; Davis, Mary; León, Blanca; Les, Don; Lin, Ping-Nan; Mashiotta, Tracy; Mountain, Keith

    2006-01-01

    Three lines of evidence for abrupt tropical climate change, both past and present, are presented. First, annually and decadally averaged δ18O and net mass-balance histories for the last 400 and 2,000 yr, respectively, demonstrate that the current warming at high elevations in the mid- to low latitudes is unprecedented for at least the last 2 millennia. Second, the continuing retreat of most mid- to low-latitude glaciers, many having persisted for thousands of years, signals a recent and abrupt change in the Earth’s climate system. Finally, rooted, soft-bodied wetland plants, now exposed along the margins as the Quelccaya ice cap (Peru) retreats, have been radiocarbon dated and, when coupled with other widespread proxy evidence, provide strong evidence for an abrupt mid-Holocene climate event that marked the transition from early Holocene (pre-5,000-yr-B.P.) conditions to cooler, late Holocene (post-5,000-yr-B.P.) conditions. This abrupt event, ≈5,200 yr ago, was widespread and spatially coherent through much of the tropics and was coincident with structural changes in several civilizations. These three lines of evidence argue that the present warming and associated glacier retreat are unprecedented in some areas for at least 5,200 yr. The ongoing global-scale, rapid retreat of mountain glaciers is not only contributing to global sea-level rise but also threatening freshwater supplies in many of the world’s most populous regions. PMID:16815970

  18. Detection of abrupt changes in dynamic systems

    NASA Technical Reports Server (NTRS)

    Willsky, A. S.

    1984-01-01

    Some of the basic ideas associated with the detection of abrupt changes in dynamic systems are presented. Multiple filter-based techniques and residual-based method and the multiple model and generalized likelihood ratio methods are considered. Issues such as the effect of unknown onset time on algorithm complexity and structure and robustness to model uncertainty are discussed.

  19. Abrupt tropical climate change: past and present.

    PubMed

    Thompson, Lonnie G; Mosley-Thompson, Ellen; Brecher, Henry; Davis, Mary; León, Blanca; Les, Don; Lin, Ping-Nan; Mashiotta, Tracy; Mountain, Keith

    2006-07-11

    Three lines of evidence for abrupt tropical climate change, both past and present, are presented. First, annually and decadally averaged delta(18)O and net mass-balance histories for the last 400 and 2,000 yr, respectively, demonstrate that the current warming at high elevations in the mid- to low latitudes is unprecedented for at least the last 2 millennia. Second, the continuing retreat of most mid- to low-latitude glaciers, many having persisted for thousands of years, signals a recent and abrupt change in the Earth's climate system. Finally, rooted, soft-bodied wetland plants, now exposed along the margins as the Quelccaya ice cap (Peru) retreats, have been radiocarbon dated and, when coupled with other widespread proxy evidence, provide strong evidence for an abrupt mid-Holocene climate event that marked the transition from early Holocene (pre-5,000-yr-B.P.) conditions to cooler, late Holocene (post-5,000-yr-B.P.) conditions. This abrupt event, approximately 5,200 yr ago, was widespread and spatially coherent through much of the tropics and was coincident with structural changes in several civilizations. These three lines of evidence argue that the present warming and associated glacier retreat are unprecedented in some areas for at least 5,200 yr. The ongoing global-scale, rapid retreat of mountain glaciers is not only contributing to global sea-level rise but also threatening freshwater supplies in many of the world's most populous regions.

  20. 75 FR 19662 - Advisory Committee on Presidential Libraries Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-15

    ... RECORDS ADMINISTRATION Advisory Committee on Presidential Libraries Meeting AGENCY: National Archives and...) announces a meeting of the Advisory Committee on Presidential Libraries. The meeting will be held to discuss the Presidential Library program and topics related to the public-private partnership between...

  1. The Persuasion of Image Building and Presidential Campaigns.

    ERIC Educational Resources Information Center

    Thomas, David A.

    In a presidential election campaign, any dimension of an image is important if it motivates the voters to favor or disfavor a candidate. Therefore, to study what motivates electoral behavior is one way to study the persuasion of image building in presidential campaigns. In this paper some of the research in presidential election campaigns is…

  2. Presidential leadership and health information technology.

    PubMed

    Brailer, David J

    2009-01-01

    There have been two pivotal contests between Congress and two presidents over the nation's investment in health information technology (IT) and whether it will improve the quality and efficiency of care. The first, between President George W. Bush and the 109th Congress, resulted in a strong declaration of presidential support for health IT and galvanized the health IT community for aggressive activism. The second was set in motion when the 111th Congress used the stimulus legislation to drive potentially disruptive changes in health IT spending and policy. We again face the question of whether presidential leadership will keep health IT on course as a driver of health reform.

  3. Abrupt transitions to a cold North Atlantic in the late Holocene

    NASA Astrophysics Data System (ADS)

    Geirsdóttir, Áslaug; Miller, Gifford; Larsen, Darren; Florian, Christopher; Pendleton, Simon

    2015-04-01

    The Holocene provides a time interval with boundary conditions similar to present, except for greenhouse gas concentrations. Recent high-resolution Northern Hemisphere records show general cooling related to orbital terms through the late Holocene, but also highly non-linear abrupt departures of centennial scale summer cold periods. These abrupt departures are evident within the last two millennia (the transitions between the Roman Warm Period (RWP, ~2,000 yr BP), the Dark Ages Cold Period (DACP, ~500-900 years AD), the Medieval Warm Period (MWP, 1000-1200 years AD) and the Little Ice Age (LIA, ~1300-1900 AD). A series of new, high-resolution and securely dated lake records from Iceland also show abrupt climate departures over the past 2 ka, characterized by shifts to persistent cold summers and an expanded cryosphere. Despite substantial differences in catchment-specific processes that dominate the lake records, the multi-proxy reconstructions are remarkably similar. After nearly a millennium with little evidence of significant climate shifts, the beginning of the first millennium AD is characterized by renewed summer cooling that leads to an expanding cryosphere. Slow summer cooling over the first five centuries is succeeded by widespread substantial cooling, with evidence for substantial expansion of glaciers and ice caps throughout our field areas between 530 and 900 AD, and an accompanying reduction in vegetation cover across much of Iceland that led to widespread landscape instability. These data suggest that the North Atlantic system began a transition into a new cold state early in the first millennium AD, which was amplified after 500 AD, until it was interrupted by warmer Medieval times between ~1000 and 1250 AD. Although severe soil erosion in Iceland is frequently associated with human settlement dated to 871 ±2 AD our reconstructions indicate that soil erosion began several centuries before settlement, during the DACP, whereas for several centuries

  4. Abrupt climate change: Mechanisms, patterns, and impacts

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2012-08-01

    In the span of only a few decades, the global temperature can soar by more than a dozen degrees Celsius, a feat that 20 years ago was considered improbable, if not impossible. But recent research in the nascent field of rapid climate change has upended the dominant views of decades past. Focusing primarily on events during and after the most recent glaciation, from 80,000 years ago, the AGU monograph Abrupt Climate Change: Mechanisms, Patterns, and Impacts, edited by Harunur Rashid, Leonid Polyak, and Ellen Mosley-Thompson, explores the transient climate transitions that were only recently uncovered in climate proxies around the world. In this interview, Eos talks to Harunur Rashid about piecing together ancient climes, the effect of abrupt change on historical civilizations, and why younger researchers may be more worried about modern warming than their teachers.

  5. Abruptness of Cascade Failures in Power Grids

    NASA Astrophysics Data System (ADS)

    Pahwa, Sakshi; Scoglio, Caterina; Scala, Antonio

    2014-01-01

    Electric power-systems are one of the most important critical infrastructures. In recent years, they have been exposed to extreme stress due to the increasing demand, the introduction of distributed renewable energy sources, and the development of extensive interconnections. We investigate the phenomenon of abrupt breakdown of an electric power-system under two scenarios: load growth (mimicking the ever-increasing customer demand) and power fluctuations (mimicking the effects of renewable sources). Our results on real, realistic and synthetic networks indicate that increasing the system size causes breakdowns to become more abrupt; in fact, mapping the system to a solvable statistical-physics model indicates the occurrence of a first order transition in the large size limit. Such an enhancement for the systemic risk failures (black-outs) with increasing network size is an effect that should be considered in the current projects aiming to integrate national power-grids into ``super-grids''.

  6. Abruptness of Cascade Failures in Power Grids

    PubMed Central

    Pahwa, Sakshi; Scoglio, Caterina; Scala, Antonio

    2014-01-01

    Electric power-systems are one of the most important critical infrastructures. In recent years, they have been exposed to extreme stress due to the increasing demand, the introduction of distributed renewable energy sources, and the development of extensive interconnections. We investigate the phenomenon of abrupt breakdown of an electric power-system under two scenarios: load growth (mimicking the ever-increasing customer demand) and power fluctuations (mimicking the effects of renewable sources). Our results on real, realistic and synthetic networks indicate that increasing the system size causes breakdowns to become more abrupt; in fact, mapping the system to a solvable statistical-physics model indicates the occurrence of a first order transition in the large size limit. Such an enhancement for the systemic risk failures (black-outs) with increasing network size is an effect that should be considered in the current projects aiming to integrate national power-grids into “super-grids”. PMID:24424239

  7. Abruptness of cascade failures in power grids.

    PubMed

    Pahwa, Sakshi; Scoglio, Caterina; Scala, Antonio

    2014-01-01

    Electric power-systems are one of the most important critical infrastructures. In recent years, they have been exposed to extreme stress due to the increasing demand, the introduction of distributed renewable energy sources, and the development of extensive interconnections. We investigate the phenomenon of abrupt breakdown of an electric power-system under two scenarios: load growth (mimicking the ever-increasing customer demand) and power fluctuations (mimicking the effects of renewable sources). Our results on real, realistic and synthetic networks indicate that increasing the system size causes breakdowns to become more abrupt; in fact, mapping the system to a solvable statistical-physics model indicates the occurrence of a first order transition in the large size limit. Such an enhancement for the systemic risk failures (black-outs) with increasing network size is an effect that should be considered in the current projects aiming to integrate national power-grids into "super-grids". PMID:24424239

  8. Abrupt percolation in small equilibrated networks

    NASA Astrophysics Data System (ADS)

    Matsoukas, Themis

    2015-05-01

    Networks can exhibit an abrupt transition in the form of a spontaneous self-organization of a sizable fraction of the population into a giant component of connected members. This behavior has been demonstrated in random graphs under suppressive rules that passively or actively attempt to delay the formation of the giant cluster. We show that suppressive rules are not a necessary condition for a sharp transition at the percolation threshold. Rather, a finite system with aggressive tendency to form a giant cluster may exhibit an instability at the percolation threshold that is relieved through an abrupt and discontinuous transition to the stable branch. We develop the theory for a class of equilibrated networks that produce this behavior and find that the discontinuous jump is especially pronounced in small networks but disappears when the size of the system is infinite.

  9. Abruptness of cascade failures in power grids.

    PubMed

    Pahwa, Sakshi; Scoglio, Caterina; Scala, Antonio

    2014-01-15

    Electric power-systems are one of the most important critical infrastructures. In recent years, they have been exposed to extreme stress due to the increasing demand, the introduction of distributed renewable energy sources, and the development of extensive interconnections. We investigate the phenomenon of abrupt breakdown of an electric power-system under two scenarios: load growth (mimicking the ever-increasing customer demand) and power fluctuations (mimicking the effects of renewable sources). Our results on real, realistic and synthetic networks indicate that increasing the system size causes breakdowns to become more abrupt; in fact, mapping the system to a solvable statistical-physics model indicates the occurrence of a first order transition in the large size limit. Such an enhancement for the systemic risk failures (black-outs) with increasing network size is an effect that should be considered in the current projects aiming to integrate national power-grids into "super-grids".

  10. 76 FR 11337 - Presidential Library Facilities; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ..., June 17, 2008 (73 FR 34197) that are the subject of this correction, NARA adopted and incorporated by... RECORDS ADMINISTRATION 36 CFR Part 1281 RIN 3095-AA82 Presidential Library Facilities; Correction AGENCY... libraries and information required in NARA's reports to Congress before accepting title to or entering...

  11. Presidential debates and change in students' attitude.

    PubMed

    McIntosh, Everton G

    2002-02-01

    The effects of debates on influencing potential voters' attitudes were assessed in a group of 45 undergraduates who watched the third presidential debate of election year 2000 between candidates Bush and Gore. A repeated measures t test indicated a significant change in immediate ratings of attitude from pretest to posttest, with Gore being rated higher at posttest.

  12. The Subtle Nature of Presidential Debate Influence.

    ERIC Educational Resources Information Center

    Pfau, Michael

    2002-01-01

    Argues that the influence of televised, general election, presidential debates on prospective voters' perceptions of participating candidates may be larger than previous research suggests. Finds that two sources of debate effects have gone largely undetected to date: those based on candidates' relational communication, and those which are…

  13. Get Real: Teaching about the Presidential Election

    ERIC Educational Resources Information Center

    McGuire, Margit; Waldman, John

    2008-01-01

    A paramount duty of education is to prepare young people for their role as citizens in a democratic society. Voting is one of the important responsibilities of a citizen but statistics indicate that young people often don't vote and don't believe they have a stake in the outcome of the presidential election. Storypath is a teaching strategy that…

  14. The Chancellor's Role in a Presidential Transition

    ERIC Educational Resources Information Center

    Appleton, James R.; Dorsey, Stuart

    2009-01-01

    Successful transitions involving a formal role for the former president, such as chancellor, are rare enough that the authors think theirs is an exceptional experience and is worth sharing, especially given the bulge of presidential retirements anticipated over the next decade. The authors believe that this model of transition can be successful,…

  15. Presidential Election '80 and the Past Presidents.

    ERIC Educational Resources Information Center

    Bolger, Charlene

    Activities in this elementary school unit about the 1980 presidential election can easily be adapted to any election. Fact sheets list the main functions of the president, 10 steps in becoming president, qualifications for the presidency, qualifications and duties of the vice president, election vocabulary, an explanation of the electoral college,…

  16. Media Nihilism and the Presidential Debates.

    ERIC Educational Resources Information Center

    Hogan, J. Michael

    1989-01-01

    Discusses the function of media nihilism--the rhetoric of "crisis and failure"--in the 1988 Presidential Debates. Examines journalists' debate questions, noting that they painted an almost wholly negative portrait of America. Suggests that the candidate who effectively "skewers" the media on its own hypocrisy should be declared the debate…

  17. Discover Presidential Log Cabins. Teacher's Discussion Guide.

    ERIC Educational Resources Information Center

    National Park Service (Dept. of Interior), Washington, DC.

    Discover Presidential Log Cabins is a set of materials designed to help educate 6-8 grade students about the significance of three log cabin sites occupied by George Washington, Ulysses Grant, Abraham Lincoln, and Theodore Roosevelt. This teacher's discussion guide is intended for use as part of a larger, comprehensive social studies program, and…

  18. 44 CFR 206.38 - Presidential determination.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Presidential determination. 206.38 Section 206.38 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY DISASTER ASSISTANCE FEDERAL DISASTER ASSISTANCE The Declaration Process §...

  19. Basic mechanism for abrupt monsoon transitions

    PubMed Central

    Levermann, Anders; Schewe, Jacob; Petoukhov, Vladimir; Held, Hermann

    2009-01-01

    Monsoon systems influence the livelihood of hundreds of millions of people. During the Holocene and last glacial period, rainfall in India and China has undergone strong and abrupt changes. Though details of monsoon circulations are complicated, observations reveal a defining moisture-advection feedback that dominates the seasonal heat balance and might act as an internal amplifier, leading to abrupt changes in response to relatively weak external perturbations. Here we present a minimal conceptual model capturing this positive feedback. The basic equations, motivated by observed relations, yield a threshold behavior, robust with respect to addition of other physical processes. Below this threshold in net radiative influx, R c, no conventional monsoon can develop; above R c, two stable regimes exist. We identify a nondimensional parameter l that defines the threshold and makes monsoon systems comparable with respect to the character of their abrupt transition. This dynamic similitude may be helpful in understanding past and future variations in monsoon circulation. Within the restrictions of the model, we compute R c for current monsoon systems in India, China, the Bay of Bengal, West Africa, North America, and Australia, where moisture advection is the main driver of the circulation. PMID:19858472

  20. Abrupt switch to migratory night flight in a wild migratory songbird

    PubMed Central

    Zúñiga, Daniel; Falconer, Jade; Fudickar, Adam M.; Jensen, Willi; Schmidt, Andreas; Wikelski, Martin; Partecke, Jesko

    2016-01-01

    Every year, billions of wild diurnal songbirds migrate at night. To do so, they shift their daily rhythm from diurnality to nocturnality. In captivity this is observed as a gradual transition of daytime activity developing into nocturnal activity, but how wild birds prepare their daily rhythms for migration remains largely unknown. Using an automated radio-telemetry system, we compared activity patterns of free-living migrant and resident European blackbirds (Turdus merula) in a partially migratory population during the pre-migratory season. We found that activity patterns between migrant and resident birds did not differ during day and night. Migrants did not change their daily rhythm in a progressive manner as has been observed in captivity, but instead abruptly became active during the night of departure. The rapid shift in rhythmicity might be more common across migratory songbird species, but may not have been observed before in wild animals due to a lack of technology. PMID:27666200

  1. Observational facts of sustained departure plateau vortexes

    NASA Astrophysics Data System (ADS)

    Yu, Shuhua; Gao, Wenliang; Peng, Jun; Xiao, Yuhua

    2014-02-01

    By using the twice-daily atmospheric observation data from 1998 to 2012, station rainfall data, Tropical Rainfall Measure Mission (TRMM) data, as well as the plateau vortex and shear line year book, characteristics of the sustained departure plateau vortexes (SDPVs) are analyzed. Some new useful observational facts and understanding are obtained about the SDPV activities. The following results are obtained. (1) The active period of SDPVs is from June to August, most in July, unlike that of the unsustained departure plateau vortexes (UDPVs), which have same occurrence frequencies in the three summer months. (2) The SDPVs, generated mainly in the Qumalai neighborhood and situated in a sheared surrounding, move eastward or northeastward, while the UDPVs are mainly led by the upper-level trough, and move eastward or southeastward. (3) The SDPVs influence wide areas of China, even far to the Korean Peninsula, Japan, and Vietnam. (4) The SDPVs change their intensities and properties on the way to the east. Most of them become stronger and produce downpour or sustained regional rainstorms to the south of Yellow River. (5) The longer the SDPV sustains, the more baroclinity it has. (6) When an SDPV moves into the sea, its central pressure descends and rainfall increases in all probability. (7) An SDPV might spin over the bend of the Yellow River when there exists a tropical cyclone in the East China Sea. It could also move oppositely to a landed tropical low pressure originated from the sea to the east of Taiwan or from the South China Sea.

  2. Scheduling and Separating Departures Crossing Arrival Flows in Shared Airspace

    NASA Technical Reports Server (NTRS)

    Chevalley, Eric; Parke, Bonny K.; Lee, Paul; Omar, Faisal; Lee, Hwasoo; Beinert, Nancy; Kraut, Joshua M.; Palmer, Everett

    2013-01-01

    Flight efficiency and reduction of flight delays are among the primary goals of NextGen. In this paper, we propose a concept of shared airspace where departures fly across arrival flows, provided gaps are available in these flows. We have explored solutions to separate departures temporally from arrival traffic and pre-arranged procedures to support controllers' decisions. We conducted a Human-in-the-Loop simulation and assessed the efficiency and safety of 96 departures from the San Jose airport (SJC) climbing across the arrival airspace of the Oakland and San Francisco arrival flows. In our simulation, the SJC tower had a tool to schedule departures to fly across predicted gaps in the arrival flow. When departures were mistimed and separation could not be ensured, a safe but less efficient route was provided to the departures to fly under the arrival flows. A coordination using a point-out procedure allowed the arrival controller to control the SJC departures right after takeoff. We manipulated the accuracy of departure time (accurate vs. inaccurate) as well as which sector took control of the departures after takeoff (departure vs. arrival sector) in a 2x2 full factorial plan. Results show that coordination time decreased and climb efficiency increased when the arrival sector controlled the aircraft right after takeoff. Also, climb efficiency increased when the departure times were more accurate. Coordination was shown to be a critical component of tactical operations in shared airspace. Although workload, coordination, and safety were judged by controllers as acceptable in the simulation, it appears that in the field, controllers would need improved tools and coordination procedures to support this procedure.

  3. Approaching the Edge of Abrupt Climate Change

    NASA Astrophysics Data System (ADS)

    Ramadhin, C.; Yi, C.

    2015-12-01

    The phenomenon of Abrupt Climate Change (ACC) became evident as paleoclimate data analyses began revealing that Earth's climate has the ability to rapidly switch from one state to the next in just a few decades after thresholds are crossed. Previously paleo-climatologists thought these switches were gradual but now there is growing concern to identify thresholds and the dominant feedback mechanisms that propel systems toward thresholds. Current human civilization relies heavily on climate stability and ACC threatens immense disruption with potentially disastrous consequences for all ecosystems. Therefore, prediction of the climate system's approach to threshold values would prove vital for the resilience of civilization through development of appropriate adaptation strategies when that shift occurs. Numerous studies now establish that earth systems are experiencing dramatic changes both by system interactions and anthropogenic sources adding urgency for comprehensive knowledge of tipping point identification. Despite this, predictions are difficult due to the immensity of interactions among feedback mechanisms. In this paper, we attempt to narrow this broad spectrum of critical feedback mechanisms by reviewing several publications on role of feedbacks in initiating past climate transitions establishing the most critical ones and significance in current climate changes. Using a compilation of paleoclimate datasets we compared the rates of deglaciations with that of glacial inceptions, which are approximately 5-10 times slower. We hypothesize that the critical feedbacks are unique to each type of transition such that warmings are dominated by the ice-albedo feedback while coolings are a combination of temperature - CO2 and temperature-precipitation followed by the ice-albedo feedbacks. Additionally, we propose the existence of a commonality in the dominant trigger feedbacks for astronomical and millennial timescale abrupt climate shifts and as such future studies

  4. 14 CFR 93.125 - Arrival or departure reservation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Arrival or departure reservation. 93.125 Section 93.125 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... § 93.125 Arrival or departure reservation. Except between 12 Midnight and 6 a.m. local time, no...

  5. Why Do They Leave? Departure from the Student Affairs Profession

    ERIC Educational Resources Information Center

    Frank, Tara E.

    2013-01-01

    Departure among student affairs administrators in higher education has been an issue for decades (Evans, 1988; Lorden, 1998; Tull, 2006). Rates of departure from student affairs within the first five years of experience are estimated at 50% to 60% (Holmes, Verrier, & Chisholm, 1983; Lorden, 1998; Tull, 2006). However, there is very little…

  6. Characterization of Tactical Departure Scheduling in the National Airspace System

    NASA Technical Reports Server (NTRS)

    Capps, Alan; Engelland, Shawn A.

    2011-01-01

    This paper discusses and analyzes current day utilization and performance of the tactical departure scheduling process in the National Airspace System (NAS) to understand the benefits in improving this process. The analysis used operational air traffic data from over 1,082,000 flights during the month of January, 2011. Specific metrics included the frequency of tactical departure scheduling, site specific variances in the technology's utilization, departure time prediction compliance used in the tactical scheduling process and the performance with which the current system can predict the airborne slot that aircraft are being scheduled into from the airport surface. Operational data analysis described in this paper indicates significant room for improvement exists in the current system primarily in the area of reduced departure time prediction uncertainty. Results indicate that a significant number of tactically scheduled aircraft did not meet their scheduled departure slot due to departure time uncertainty. In addition to missed slots, the operational data analysis identified increased controller workload associated with tactical departures which were subject to traffic management manual re-scheduling or controller swaps. An analysis of achievable levels of departure time prediction accuracy as obtained by a new integrated surface and tactical scheduling tool is provided to assess the benefit it may provide as a solution to the identified shortfalls. A list of NAS facilities which are likely to receive the greatest benefit from the integrated surface and tactical scheduling technology are provided.

  7. Transfer and Dropout: Different Forms of Student Departure in Norway

    ERIC Educational Resources Information Center

    Hovdhaugen, Elisabeth

    2009-01-01

    This article examines student departure from university, based on data from a survey of undergraduate university students in Norway conducted in 2005. The survey maps students' progression through higher education, and the analysis focuses on the different types of departure and their causes. More than 50% of all university students left the…

  8. 46 CFR 45.191 - Pre-departure requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Pre-departure requirements. 45.191 Section 45.191 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES GREAT LAKES LOAD LINES Unmanned River Barges on Lake Michigan Routes § 45.191 Pre-departure requirements. Before beginning...

  9. 46 CFR 45.191 - Pre-departure requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Pre-departure requirements. 45.191 Section 45.191 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES GREAT LAKES LOAD LINES Unmanned River Barges on Lake Michigan Routes § 45.191 Pre-departure requirements. Before beginning...

  10. 46 CFR 45.191 - Pre-departure requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Pre-departure requirements. 45.191 Section 45.191 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES GREAT LAKES LOAD LINES Unmanned River Barges on Lake Michigan Routes § 45.191 Pre-departure requirements. Before beginning...

  11. 46 CFR 45.191 - Pre-departure requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Pre-departure requirements. 45.191 Section 45.191 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES GREAT LAKES LOAD LINES Unmanned River Barges on Lake Michigan Routes § 45.191 Pre-departure requirements. Before beginning...

  12. Moving On: Voluntary Staff Departures at Small Colleges and Universities

    ERIC Educational Resources Information Center

    Kortegast, Carrie A.; Hamrick, Florence A.

    2009-01-01

    Although voluntary departures are frequent among new professional student affairs staff members at small colleges and universities, there is little systematic study of the processes involved in departing a job at one campus to accept a student affairs position at another. Potentially awkward dynamics surrounding staff departures can complicate…

  13. 14 CFR 121.617 - Alternate airport for departure.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Alternate airport for departure. 121.617... Alternate airport for departure. (a) If the weather conditions at the airport of takeoff are below the landing minimums in the certificate holder's operations specifications for that airport, no person...

  14. 14 CFR 125.365 - Alternate airport for departure.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Alternate airport for departure. 125.365... § 125.365 Alternate airport for departure. (a) If the weather conditions at the airport of takeoff are below the landing minimums in the certificate holder's operations specifications for that airport,...

  15. Presidential Symposia and Events: Salt Lake City

    NASA Astrophysics Data System (ADS)

    Walworth, Frank

    2009-03-01

    During 2009 ACS President Thomas H. Lane is committed to promoting education, building new and productive relationships that support the ACS strategic plan, and developing outcome-based metrics to guide the Society. At the 237th ACS national meeting in Salt Lake City, Lane is supporting six presidential symposia and events. Please consult the online technical program (accessed Jan 2009) for up-to-date information.

  16. Abrupt plate accelerations shape rifted continental margins

    NASA Astrophysics Data System (ADS)

    Brune, Sascha; Williams, Simon E.; Butterworth, Nathaniel P.; Müller, R. Dietmar

    2016-08-01

    Rifted margins are formed by persistent stretching of continental lithosphere until breakup is achieved. It is well known that strain-rate-dependent processes control rift evolution, yet quantified extension histories of Earth’s major passive margins have become available only recently. Here we investigate rift kinematics globally by applying a new geotectonic analysis technique to revised global plate reconstructions. We find that rifted margins feature an initial, slow rift phase (less than ten millimetres per year, full rate) and that an abrupt increase of plate divergence introduces a fast rift phase. Plate acceleration takes place before continental rupture and considerable margin area is created during each phase. We reproduce the rapid transition from slow to fast extension using analytical and numerical modelling with constant force boundary conditions. The extension models suggest that the two-phase velocity behaviour is caused by a rift-intrinsic strength–velocity feedback, which can be robustly inferred for diverse lithosphere configurations and rheologies. Our results explain differences between proximal and distal margin areas and demonstrate that abrupt plate acceleration during continental rifting is controlled by the nonlinear decay of the resistive rift strength force. This mechanism provides an explanation for several previously unexplained rapid absolute plate motion changes, offering new insights into the balance of plate driving forces through time.

  17. Abrupt climate-independent fire regime changes

    USGS Publications Warehouse

    Pausas, Juli G.; Keeley, Jon E.

    2014-01-01

    Wildfires have played a determining role in distribution, composition and structure of many ecosystems worldwide and climatic changes are widely considered to be a major driver of future fire regime changes. However, forecasting future climatic change induced impacts on fire regimes will require a clearer understanding of other drivers of abrupt fire regime changes. Here, we focus on evidence from different environmental and temporal settings of fire regimes changes that are not directly attributed to climatic changes. We review key cases of these abrupt fire regime changes at different spatial and temporal scales, including those directly driven (i) by fauna, (ii) by invasive plant species, and (iii) by socio-economic and policy changes. All these drivers might generate non-linear effects of landscape changes in fuel structure; that is, they generate fuel changes that can cross thresholds of landscape continuity, and thus drastically change fire activity. Although climatic changes might contribute to some of these changes, there are also many instances that are not primarily linked to climatic shifts. Understanding the mechanism driving fire regime changes should contribute to our ability to better assess future fire regimes.

  18. Abrupt plate accelerations shape rifted continental margins.

    PubMed

    Brune, Sascha; Williams, Simon E; Butterworth, Nathaniel P; Müller, R Dietmar

    2016-08-11

    Rifted margins are formed by persistent stretching of continental lithosphere until breakup is achieved. It is well known that strain-rate-dependent processes control rift evolution, yet quantified extension histories of Earth's major passive margins have become available only recently. Here we investigate rift kinematics globally by applying a new geotectonic analysis technique to revised global plate reconstructions. We find that rifted margins feature an initial, slow rift phase (less than ten millimetres per year, full rate) and that an abrupt increase of plate divergence introduces a fast rift phase. Plate acceleration takes place before continental rupture and considerable margin area is created during each phase. We reproduce the rapid transition from slow to fast extension using analytical and numerical modelling with constant force boundary conditions. The extension models suggest that the two-phase velocity behaviour is caused by a rift-intrinsic strength--velocity feedback, which can be robustly inferred for diverse lithosphere configurations and rheologies. Our results explain differences between proximal and distal margin areas and demonstrate that abrupt plate acceleration during continental rifting is controlled by the nonlinear decay of the resistive rift strength force. This mechanism provides an explanation for several previously unexplained rapid absolute plate motion changes, offering new insights into the balance of plate driving forces through time.

  19. Abrupt plate accelerations shape rifted continental margins.

    PubMed

    Brune, Sascha; Williams, Simon E; Butterworth, Nathaniel P; Müller, R Dietmar

    2016-08-11

    Rifted margins are formed by persistent stretching of continental lithosphere until breakup is achieved. It is well known that strain-rate-dependent processes control rift evolution, yet quantified extension histories of Earth's major passive margins have become available only recently. Here we investigate rift kinematics globally by applying a new geotectonic analysis technique to revised global plate reconstructions. We find that rifted margins feature an initial, slow rift phase (less than ten millimetres per year, full rate) and that an abrupt increase of plate divergence introduces a fast rift phase. Plate acceleration takes place before continental rupture and considerable margin area is created during each phase. We reproduce the rapid transition from slow to fast extension using analytical and numerical modelling with constant force boundary conditions. The extension models suggest that the two-phase velocity behaviour is caused by a rift-intrinsic strength--velocity feedback, which can be robustly inferred for diverse lithosphere configurations and rheologies. Our results explain differences between proximal and distal margin areas and demonstrate that abrupt plate acceleration during continental rifting is controlled by the nonlinear decay of the resistive rift strength force. This mechanism provides an explanation for several previously unexplained rapid absolute plate motion changes, offering new insights into the balance of plate driving forces through time. PMID:27437571

  20. A Mixed Integer Linear Program for Airport Departure Scheduling

    NASA Technical Reports Server (NTRS)

    Gupta, Gautam; Jung, Yoon Chul

    2009-01-01

    Aircraft departing from an airport are subject to numerous constraints while scheduling departure times. These constraints include wake-separation constraints for successive departures, miles-in-trail separation for aircraft bound for the same departure fixes, and time-window or prioritization constraints for individual flights. Besides these, emissions as well as increased fuel consumption due to inefficient scheduling need to be included. Addressing all the above constraints in a single framework while allowing for resequencing of the aircraft using runway queues is critical to the implementation of the Next Generation Air Transport System (NextGen) concepts. Prior work on airport departure scheduling has addressed some of the above. However, existing methods use pre-determined runway queues, and schedule aircraft from these departure queues. The source of such pre-determined queues is not explicit, and could potentially be a subjective controller input. Determining runway queues and scheduling within the same framework would potentially result in better scheduling. This paper presents a mixed integer linear program (MILP) for the departure-scheduling problem. The program takes as input the incoming sequence of aircraft for departure from a runway, along with their earliest departure times and an optional prioritization scheme based on time-window of departure for each aircraft. The program then assigns these aircraft to the available departure queues and schedules departure times, explicitly considering wake separation and departure fix restrictions to minimize total delay for all aircraft. The approach is generalized and can be used in a variety of situations, and allows for aircraft prioritization based on operational as well as environmental considerations. We present the MILP in the paper, along with benefits over the first-come-first-serve (FCFS) scheme for numerous randomized problems based on real-world settings. The MILP results in substantially reduced

  1. Benefit Assessment of the Precision Departure Release Capability Concept

    NASA Technical Reports Server (NTRS)

    Palopo, Kee; Chatterji, Gano B.; Lee, Hak-Tae

    2011-01-01

    A Precision Departure Release Capability concept is being evaluated by both the National Aeronautics and Space Administration and the Federal Aviation Administration as part of a larger goal of improving throughput, efficiency and capacity in integrated departure, arrival and surface operations. The concept is believed to have the potential of increasing flight efficiency and throughput by avoiding missing assigned slots and minimizing speed increase or path stretch to recover the slot. The main thrust of the paper is determining the impact of early and late departures from the departure runway when an aircraft has a slot assigned either at a meter fix or at the arrival airport. Results reported in the paper are for two scenarios. The first scenario considers flights out of Dallas/Fort Worth destined for Hartsfield-Jackson International Airport in Atlanta flying through the Meridian meter-fix in the Memphis Center with miles-in-trail constraints. The second scenario considers flights destined to George Bush Intercontinental/Houston Airport with specified airport arrival rate constraint. Results show that delay reduction can be achieved by allowing reasonable speed changes in scheduling. It was determined that the traffic volume between Dallas/Fort Worth and Atlanta via the Meridian fix is low and the departures times are spread enough that large departure schedule uncertainty can be tolerated. Flights can depart early or late within 90 minutes without accruing much more delay due to miles-in-trail constraint at the Meridian fix. In the Houston scenario, 808 arrivals from 174 airports were considered. Results show that delay experienced by the 16 Dallas/Fort Worth departures is higher if initial schedules of the remaining 792 flights are kept unaltered while they are rescheduled. Analysis shows that the probability of getting the initially assigned slot back after perturbation and rescheduling decreases with increasing standard deviation of the departure delay

  2. Sufficient condition for Gaussian departure in turbulence.

    PubMed

    Tordella, Daniela; Iovieno, Michele; Bailey, Peter Roger

    2008-01-01

    The interaction of two isotropic turbulent fields of equal integral scale but different kinetic energy generates the simplest kind of inhomogeneous turbulent field. In this paper we present a numerical experiment where two time decaying isotropic fields of kinetic energies E1 and E2 initially match over a narrow region. Within this region the kinetic energy varies as a hyperbolic tangent. The following temporal evolution produces a shearless mixing. The anisotropy and intermittency of velocity and velocity derivative statistics is observed. In particular the asymptotic behavior in time and as a function of the energy ratio E_{1}E_{2}-->infinity is discussed. This limit corresponds to the maximum observable turbulent energy gradient for a given E1 and is obtained through the limit E_{2}-->0 . A field with E_{1}E_{2}-->infinity represents a mixing which could be observed near a surface subject to a very small velocity gradient separating two turbulent fields, one of which is nearly quiescent. In this condition the turbulent penetration is maximum and reaches a value equal to 1.2 times the nominal mixing layer width. The experiment shows that the presence of a turbulent energy gradient is sufficient for the appearance of intermittency and that during the mixing process the pressure transport is not negligible with respect to the turbulent velocity transport. These findings may open the way to the hypothesis that the presence of a gradient of turbulent energy is the minimal requirement for Gaussian departure in turbulence.

  3. 75 FR 63209 - Advisory Committee on Presidential Library-Foundation Partnerships

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-14

    ... RECORDS ADMINISTRATION Advisory Committee on Presidential Library-Foundation Partnerships AGENCY: National... (NARA) announces a meeting of the Advisory Committee on Presidential Library-Foundation Partnerships... to Presidential Libraries, the Electionic Record Archives (ERA), the National Declassification...

  4. 77 FR 42767 - Advisory Committee on Presidential Library-Foundation Partnerships

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-20

    ... RECORDS ADMINISTRATION Advisory Committee on Presidential Library-Foundation Partnerships AGENCY: National Archives and Records Administration. ACTION: Renewal of Advisory Committee on Presidential Library... the National Archives and Records Administration's (NARA) Advisory Committee on Presidential...

  5. 76 FR 9760 - Presidential Academies for Teaching of American History and Civics; Office of Innovation and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-22

    ... Presidential Academies for Teaching of American History and Civics; Office of Innovation and Improvement; Overview Information; Presidential Academies for Teaching of American History and Civics; Notice Inviting... program supports the establishment of Presidential Academies for Teaching of American History and...

  6. 76 FR 26317 - Advisory Committee on Presidential Library-Foundation Partnerships

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-06

    ... Presidential Libraries, Social Media Initiatives, Processing of Presidential materials, and the Advancement of... From the Federal Register Online via the Government Publishing Office NATIONAL ARCHIVES AND RECORDS ADMINISTRATION Advisory Committee on Presidential Library-Foundation Partnerships AGENCY:...

  7. Towards Greenland Glaciation: cumulative or abrupt transition?

    NASA Astrophysics Data System (ADS)

    Tan, Ning; Dumas, Christophe; Ladant, Jean-Baptiste; Ramstein, Gilles; Contoux, Camille

    2016-04-01

    During the mid-Pliocene warming period (3-3.3 Ma BP), global annual mean temperature is warmer by 2-3 degree than pre-industrial. Greenland ice sheet volume is supposed to be a 50% reduction compared to nowadays [Haywood et al. 2010]. Around 2.7-2.6 Ma BP, just ~ 500 kyr after the warming peak of mid-Pliocene, there is already full Greenland Glaciation [Lunt et al. 2008]. How does Greenland ice sheet evolve from a half size to a glaciation level during 3 Ma - 2.5 Ma? Data show that there is a decreasing trend of atmospheric CO2 concentration from 3 Ma to 2.5 Ma [Seki et al.2010; Bartoli et al. 2011; Martinez et al. 2015]. However, a recent study [Contoux et al. 2015] suggests that a lowering of CO2 is not sufficient to initiate a perennial glaciation on Greenland and must be combined to low summer insolation, to preserve the ice sheet during insolation maximum, suggesting a cumulative process. In order to diagnose whether the ice sheet build-up is an abrupt event or a cumulative process, we carry on, for the first time, a transient simulation of climate and ice sheet evolutions from 3 Ma to 2.5 Ma. This strategy enables to investigate waxing and waning of the ice sheet during several orbital cycles. To reach this goal, we use a tri-dimensional interpolation method designed by Ladant et al. (2014) which combines the evolution of CO2 concentration, orbital parameters and Greenland ice sheet sizes in an off-line way by interpolating snapshots simulations. Thanks to this new method, we can build a transient like simulation through asynchronous coupling between GCM and ice sheet model. With this method, we may consistently answer the question of the build-up of Greenland: abrupt or cumulative process.

  8. Cesarean Delivery for a Life-threatening Preterm Placental Abruption

    PubMed Central

    Okafor, II; Ugwu, EO

    2015-01-01

    Placental abruption is one of the major life-threatening obstetric conditions. The fetomaternal outcome of a severe placental abruption depends largely on prompt maternal resuscitation and delivery. A case of severe preterm placental abruption with intrauterine fetal death. Following a failed induction of labor with a deteriorating maternal condition despite resuscitation, emergency cesarean delivery was offered with good maternal outcome. Cesarean delivery could avert further disease progression and possible maternal death in cases of severe preterm placental abruption where vaginal delivery is not imminent. However, further studies are necessary before this could be recommended for routine clinical practice. PMID:27057388

  9. Neustadt's "Presidential Power" and University Governance: A Case Study Analysis.

    ERIC Educational Resources Information Center

    Lander, Byron G.

    The relevance of Richard E. Neustadt's presidential choice making theory to a university presidency is analyzed. This theory, which was introduced in Neustadt's 1960 publication "Presidential Power," is examined in regard to situations that occurred at Kent State University (KSU): the KSU Black United Student (BUS) confrontation with the Oakland…

  10. What Not to Do during a Presidential Interview

    ERIC Educational Resources Information Center

    Pulliams, Preston

    2016-01-01

    As a presidential search consultant, Preston Pulliams has had the opportunity to observe and participate in many presidential search interviews and the meetings where hiring decisions are made. He has observed how some interview candidates simply knocked themselves out of contention by employing one or more of five poor interview strategies. In…

  11. The Sponsorship of Presidential Debates: Historical Perspectives and Alternatives.

    ERIC Educational Resources Information Center

    Hellweg, Susan A.

    This paper provides an overview of the development of sponsors for primary and general election debates at the presidential level and considers the various sponsorship alternatives for future debates. From a historical perspective, the paper discusses the major role that the broadcasting industry played in the early presidential debates and…

  12. Winnowing the Field: Candidates, Caucuses, and Presidential Elections.

    ERIC Educational Resources Information Center

    Gore, Deborah, Ed.

    1991-01-01

    This issue features articles and activities that concern the history of the presidential election process in the United States, with a special focus on Iowa's role in that process. The following features are included: "Lights, Camera, Action!"; "Presidential Whoopla"; "From Tree Stumps to Living Rooms"; "Wild Rosie's Campaign Code"; "Are You Too…

  13. A Primer on the Use of Consultants in Presidential Recruitment.

    ERIC Educational Resources Information Center

    Riesman, David; McLaughlin, Judith

    1984-01-01

    Many colleges are turning to professional consultants to help locate and recruit presidential candidates. The advantages and cautions of an outside expert are discussed. The Presidential Search and Assessment Service, a nonprofit enterprise sponsored by the Association of Governing Boards and the Association of American Colleges, is described.…

  14. 2007 NCTE Presidential Address: Where Ignorant Armies Clash by Night

    ERIC Educational Resources Information Center

    Yatvin, Joanne

    2008-01-01

    This article presents the text of Joanne Yatvin's presidential address, delivered at the NCTE Annual Convention in New York City in November 2007. The title of her presidential address, "Where Ignorant Armies Clash by Night," was taken from Matthew Arnold's (1867) poem "Dover Beach." Yatvin states that the federal government has usurped the right…

  15. The Presidential Platform on Twenty-First Century Education Goals

    ERIC Educational Resources Information Center

    Tichnor-Wagner, Ariel; Socol, Allison Rose

    2016-01-01

    As social and economic problems change, so do the goals of education reformers. This content analysis of presidential debates transcripts, state of the union addresses, and education budgets from 2000 to 2015 reveals the ways in which presidents and presidential candidates have framed education goals thus far in the twenty-first century. Using…

  16. A Conceptual Design of a Departure Planner Decision Aid

    NASA Technical Reports Server (NTRS)

    Anagnostakis, Ioannis; Idris, Husni R.; Clark, John-Paul; Feron, Eric; Hansman, R. John; Odoni, Amedeo R.; Hall, William D.

    2000-01-01

    Terminal area Air Traffic Management handles both arriving and departing traffic. To date, research work on terminal area operations has focused primarily on the arrival flow and typically departures are taken into account only in an approximate manner. However, arrivals and departures are highly coupled processes especially in the terminal airspace, with complex interactions and sharing of the same airport resources between arrivals and departures taking place in practically every important terminal area. Therefore, the addition of automation aids for departures, possibly in co-operation with existing arrival flow automation systems, could have a profound contribution in enhancing the overall efficiency of airport operations. This paper presents the conceptual system architecture for such an automation aid, the Departure Planner (DP). This architecture can be used as a core in the development of decision-aiding systems to assist air traffic controllers in improving the performance of departure operations and optimize runway time allocation among different operations at major congested airports. The design of such systems is expected to increase the overall efficiency of terminal area operations and yield benefits for all stakeholders involved in Air Traffic Management (ATM) operations, users as well as service providers.

  17. Towards Greenland Glaciation: Cumulative or Abrupt Transition?

    NASA Astrophysics Data System (ADS)

    Tan, N.; Ramstein, G.; Contoux, C.; Ladant, J. B.; Dumas, C.; Donnadieu, Y.

    2014-12-01

    The insolation evolution [Laskar 2004] from 4 to 2.5 Ma depicts a series of three summer solstice insolation minima between 2.7 and 2.6 Ma, but there are other more important summer solstice minima notably around 3.82 and 3.05 Ma. On such a time span of more than 1 Ma, data shows that there are variations in the evolution of atmospheric CO2 concentration with a local maximum around 3 Ma [Seki et al.2010; Bartoli et al. 2011], before a decrease between 3 and 2.6 Ma. The latter, suggesting an abrupt ice sheet inception around 2.7 Ma, has been shown to be a major culprit for the full Greenland Glaciation [Lunt et al. 2008]. However, a recent study [Contoux et al. 2014, in review] suggests that a lowering of CO2 is not sufficient to initiate a glaciation on Greenland and must be combined to low summer insolation, with surviving ice during insolation maximum, suggesting a cumulative process in the first place, which could further lead to full glaciation at 2.7 Ma. Through a new tri-dimensional interpolation method implemented within the asynchronous coupling between an atmosphere ocean general circulation model (IPSL-CM5A) and an ice sheet model (GRISLI), we investigate the transient evolution of Greenland ice sheet during the Pliocene to diagnose whether the ice sheet inception is an abrupt event or rather a cumulative process, involving waxing and waning of the ice sheet during several orbital cycles. ReferencesBartoli, G., Hönisch, B., & Zeebe, R. E. (2011). Atmospheric CO2 decline during the Pliocene intensification of Northern Hemisphere glaciations. Paleoceanography, 26(4). Contoux C, Dumas C, Ramstein G, Jost A, Dolan A. M. (2014) Modelling Greenland Ice sheet inception and sustainability during the late Pliocene. (in review for Earth and Planetary Science Letters.).Laskar, J., Robutel, P., Joutel, F., Gastineau, M., Correia, A. C. M., & Levrard, B. (2004). A long-term numerical solution for the insolation quantities of the Earth. Astronomy & Astrophysics, 428

  18. Does Television Viewership Predict Presidential Election Outcomes?

    PubMed Central

    Barfar, Arash; Padmanabhan, Balaji

    2015-01-01

    Abstract The days of surprise about actual election outcomes in the big data world are likely to be fewer in the years ahead, at least to those who may have access to such data. In this paper we highlight the potential for forecasting the Unites States presidential election outcomes at the state and county levels based solely on the data about viewership of television programs. A key consideration for relevance is that given the infrequent nature of elections, such models are useful only if they can be trained using recent data on viewership. However, the target variable (election outcome) is usually not known until the election is over. Related to this, we show here that such models may be trained with the television viewership data in the “safe” states (the ones where the outcome can be assumed even in the days preceding elections) to potentially forecast the outcomes in the swing states. In addition to their potential to forecast, these models could also help campaigns target programs for advertisements. Nearly two billion dollars were spent on television advertising in the 2012 presidential race, suggesting potential for big data–driven optimization of campaign spending. PMID:26487986

  19. Presidential inability: Filling in the gaps.

    PubMed

    Feerick, John D

    2014-01-01

    This article focuses on potential gaps caused by the absence from the Twenty-Fifth Amendment of provisions to deal with the disability of a Vice President and the omission from the statutory line of succession law of provisions comparable to Sections 3 and 4 of the Twenty-Fifth Amendment for when there is an able Vice President. The analysis offers a critical review of the latent ambiguities in the succession provision to the United States Constitution, noting problems that have arisen from the time of the Constitutional Convention, to John Tyler's accession to office, to numerous disability crises that presented themselves throughout the twentieth century, to the present day. As the world becomes more complex and threats to the presidency more common, continued examination of our succession structure and its adequacy for establishing clear and effective presidential succession provisions under a broad range of circumstances is of paramount concern. This article embraces this robust discussion by offering some suggestions for improving the system in a way that does not require a constitutional amendment. The first part of the analysis traces the events that have driven the development of the nation's succession procedures. The second part examines the inadequacies, or "gaps," that remain in the area of presidential inability, and the third part sets forth recommendations for resolving these gaps.

  20. Going, Going, Gone: Localizing Abrupt Offsets of Moving Objects

    ERIC Educational Resources Information Center

    Maus, Gerrit W.; Nijhawan, Romi

    2009-01-01

    When a moving object abruptly disappears, this profoundly influences its localization by the visual system. In Experiment 1, 2 aligned objects moved across the screen, and 1 of them abruptly disappeared. Observers reported seeing the objects misaligned at the time of the offset, with the continuing object leading. Experiment 2 showed that the…

  1. 3 CFR - Presidential Determination on Eligibility of the Federal Republic of Somalia To Receive Defense...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 3 The President 1 2014-01-01 2014-01-01 false Presidential Determination on Eligibility of the Federal Republic of Somalia To Receive Defense Articles and Defense Services Under the Foreign Assistance Act of 1961, as Amended, and the Arms Export Control Act, as Amended Presidential Documents Other Presidential Documents Presidential...

  2. 3 CFR - The Presidential POWER Initiative: Protecting Our Workers and Ensuring Reemployment

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 3 The President 1 2011-01-01 2011-01-01 false The Presidential POWER Initiative: Protecting Our Workers and Ensuring Reemployment Presidential Documents Other Presidential Documents Memorandum of July 19, 2010 The Presidential POWER Initiative: Protecting Our Workers and Ensuring Reemployment Memorandum for the Heads of Executive Departments...

  3. 3 CFR - Presidential Determination on the Eligibility of South Sudan To Receive Defense Articles and...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 3 The President 1 2013-01-01 2013-01-01 false Presidential Determination on the Eligibility of South Sudan To Receive Defense Articles and Defense Services Under the Foreign Assistance Act of 1961, as Amended, and the Arms Export Control Act, as Amended Presidential Documents Other Presidential Documents Presidential Determination No. 2012-4...

  4. 11 CFR 9037.3 - Deposits of Presidential primary matching funds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Deposits of Presidential primary matching funds. 9037.3 Section 9037.3 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: PRESIDENTIAL PRIMARY MATCHING FUND PAYMENTS AND REPORTING § 9037.3 Deposits of Presidential primary...

  5. 11 CFR 9037.3 - Deposits of Presidential primary matching funds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 11 Federal Elections 1 2011-01-01 2011-01-01 false Deposits of Presidential primary matching funds. 9037.3 Section 9037.3 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: PRESIDENTIAL PRIMARY MATCHING FUND PAYMENTS AND REPORTING § 9037.3 Deposits of Presidential primary...

  6. Mimicry Is Presidential: Linguistic Style Matching in Presidential Debates and Improved Polling Numbers.

    PubMed

    Romero, Daniel M; Swaab, Roderick I; Uzzi, Brian; Galinsky, Adam D

    2015-10-01

    The current research used the contexts of U.S. presidential debates and negotiations to examine whether matching the linguistic style of an opponent in a two-party exchange affects the reactions of third-party observers. Building off communication accommodation theory (CAT), interaction alignment theory (IAT), and processing fluency, we propose that language style matching (LSM) will improve subsequent third-party evaluations because matching an opponent's linguistic style reflects greater perspective taking and will make one's arguments easier to process. In contrast, research on status inferences predicts that LSM will negatively impact third-party evaluations because LSM implies followership. We conduct two studies to test these competing hypotheses. Study 1 analyzed transcripts of U.S. presidential debates between 1976 and 2012 and found that candidates who matched their opponent's linguistic style increased their standing in the polls. Study 2 demonstrated a causal relationship between LSM and third-party observer evaluations using negotiation transcripts.

  7. Precision Departure Release Capability (PDRC): NASA to FAA Research Transition

    NASA Technical Reports Server (NTRS)

    Engelland, Shawn; Davis, Thomas J.

    2013-01-01

    After takeoff, aircraft must merge into en route (Center) airspace traffic flows which may be subject to constraints that create localized demand-capacity imbalances. When demand exceeds capacity, Traffic Management Coordinators (TMCs) and Frontline Managers (FLMs) often use tactical departure scheduling to manage the flow of departures into the constrained Center traffic flow. Tactical departure scheduling usually involves use of a Call for Release (CFR) procedure wherein the Tower must call the Center to coordinate a release time prior to allowing the flight to depart. In present-day operations release times are computed by the Center Traffic Management Advisor (TMA) decision support tool based upon manual estimates of aircraft ready time verbally communicated from the Tower to the Center. The TMA-computed release time is verbally communicated from the Center back to the Tower where it is relayed to the Local controller as a release window that is typically three minutes wide. The Local controller will manage the departure to meet the coordinated release time window. Manual ready time prediction and verbal release time coordination are labor intensive and prone to inaccuracy. Also, use of release time windows adds uncertainty to the tactical departure process. Analysis of more than one million flights from January 2011 indicates that a significant number of tactically scheduled aircraft missed their en route slot due to ready time prediction uncertainty. Uncertainty in ready time estimates may result in missed opportunities to merge into constrained en route flows and lead to lost throughput. Next Generation Air Transportation System plans call for development of Tower automation systems capable of computing surface trajectory-based ready time estimates. NASA has developed the Precision Departure Release Capability (PDRC) concept that improves tactical departure scheduling by automatically communicating surface trajectory-based ready time predictions and

  8. Presidential leadership in the development of the US space program

    NASA Technical Reports Server (NTRS)

    Launius, Roger D. (Editor); Mccurdy, Howard E. (Editor)

    1994-01-01

    Papers presented at a historical symposium on Presidential leadership in the space program include the following: 'The Imperial Presidency in the History of Space Exploration'; 'The Reluctant Racer: Dwight D. Eisenhower and United States Space Policy'; 'Kennedy and the Decision to Go to the Moon'; 'Johnson, Project Apollo, and the Politics of Space Program Planning'; 'The Presidency, Congress, and the Deceleration of the U.S. Space Program in the 1970s'; 'Politics not Science: The U.S. Space Program in the Reagan and Bush Years'; 'Presidential Leadership and International Aspects of the Space Program'; 'National Leadership and Presidential Power'; and 'Epilogue: Beyond NASA Exceptionalism'.

  9. Presidential Citation for Science and Society

    NASA Astrophysics Data System (ADS)

    2012-07-01

    AGU presented its Presidential Citation for Science and Society to three recipients at a reception on 1 May 2012 in the Rayburn House Office Building as part of the inaugural AGU Science Policy Conference. Google Earth, Jane Lubchenco, who is the under secretary of Commerce for oceans and atmosphere and administrator of the National Oceanic and Atmospheric Administration, and Sen. Olympia Snowe (R-Maine) were recognized for their leadership and vision in shaping policy and heightening public awareness of the value of Earth and space science. “This is an important award because with it AGU brings to light the importance of cutting-edge use-inspired science that helps people, communities, and businesses adapt to climate change and sustainably manage our oceans and coasts,” Lubchenco said.

  10. Presidential candidates focus on energy policy

    SciTech Connect

    Lessard, P.; Belcher, J.

    1996-09-01

    When gasoline prices skyrocketed this past spring, sparking outcries from both the American public and lawmakers on Capitol Hill, the need for a national energy policy suddenly was pushed to the forefront. The attention the higher gasoline prices received has helped focus debate on an even more pressing issue-the real threat to the U.S. economy and national security when Americans cannot get enough oil, regardless of price, to fuel their industrial and transportation needs and, in some parts of the country, to heat their homes. While presidential candidates Bill Clinton and Bob Dole disagree with each other in many areas, with energy policy being no exception, both have expressed the opinion that the U.S. needs to be less reliant on foreign, and often unstable, countries for sources of fuel, such as oil. An exclusive interview with the candidates` respective campaigns about their views on issues facing the domestic oil and natural gas industry is presented.

  11. Centennial Presidential Perspective: Dr. Alfred Blalock

    PubMed Central

    Beaty, Claude A.; George, Timothy J.; Conte, John V.

    2014-01-01

    Great men are not a common occurrence. Indeed, they are a rare find. Though respected and lauded in their time, it is only in retrospect that their true contributions can be adequately measured as a surgeon, an educator and a scientist. Such is the case of Dr. Alfred Blalock. Many have considered him the father of modern cardiac surgery. All consider his “blue baby” operation to be one of the landmarks of cardiac surgery and, as the chief of surgery at Johns Hopkins, he trained many who would become the leaders of our discipline. His continual reach for excellence helped him to not only affect, but revolutionize the paradigm of surgical research, an understanding of the physiology of shock and the surgical management of pulmonic stenosis/atresia. Dr. Blalock was the 30th president of the American Association for Thoracic Surgery and his presidential address was given in 1951. PMID:22248679

  12. Numerical solution of optimal departure frequency of Taipei TMS

    NASA Astrophysics Data System (ADS)

    Young, Lih-jier; Chiu, Chin-Hsin

    2016-05-01

    Route Number 5 (Bannan Line) of Taipei Mass Rapid Transit (MRT) is the most popular line in the Taipei Metro System especially during rush hours periods. It has been estimated there are more than 8,000 passengers on the ticket platform during 18:00∼19:00 at Taipei main station. The purpose of this research is to predict a specific departure frequency of passengers per train. Monte Carlo Simulation will be used to optimize departure frequency according to the passenger information provided by 22 stations, i.e., 22 random variables of route number 5. It is worth mentioning that we used 30,000 iterations to get the different samples of the optimization departure frequency, i.e., 10 trains/hr which matches the practical situation.

  13. Reliability analysis of roadway departure risk using stochastic processes

    NASA Astrophysics Data System (ADS)

    Rey, G.; Clair, D.; Fogli, M.; Bernardin, F.

    2011-05-01

    The work presented here aims to develop a warning device to prevent roadway departure while cornering. Given the random variability arising from the driver, the vehicle and the infrastructure at the entrance of the curve, a probabilistic strategy is adopted to assess the roadway departure risk. Random variables and processes are introduced in a specifically developed vehicle dynamics model. The driver's behaviours are deduced from real traffic measurements. Structural reliability methods are employed to compute a roadway departure risk index, used to take the decision of an alarm triggering. Particular care is brought to the reduction of the computational cost. Refinements made on the standard reliability methods to handle with the model non-linearities and the stochastic dimension are presented.

  14. Probabilistic assessment of roadway departure risk in a curve

    NASA Astrophysics Data System (ADS)

    Rey, G.; Clair, D.; Fogli, M.; Bernardin, F.

    2011-10-01

    Roadway departure while cornering constitutes a major part of car accidents and casualties in France. Even though drastic policy about overspeeding contributes to reduce accidents, there obviously exist other factors. This article presents the construction of a probabilistic strategy for the roadway departure risk assessment. A specific vehicle dynamic model is developed in which some parameters are modelled by random variables. These parameters are deduced from a sensitivity analysis to ensure an efficient representation of the inherent uncertainties of the system. Then, structural reliability methods are employed to assess the roadway departure risk in function of the initial conditions measured at the entrance of the curve. This study is conducted within the French national road safety project SARI that aims to implement a warning systems alerting the driver in case of dangerous situation.

  15. The Effects of the Uncertainty of Departures on Multi-Center Traffic Management Advisor (TMA) Scheduling

    NASA Technical Reports Server (NTRS)

    Thipphavong, Jane; Landry, Steven J.

    2005-01-01

    The Multi-center Traffic Management Advisor (McTMA) provides a platform for regional or national traffic flow management, by allowing long-range cooperative time-based metering to constrained resources, such as airports or air traffic control center boundaries. Part of the demand for resources is made up of proposed departures, whose actual departure time is difficult to predict. For this reason, McTMA does not schedule the departures in advance, but rather relies on traffic managers to input their requested departure time. Because this happens only a short while before the aircraft's actual departure, McTMA is unable to accurately predict the amount of delay airborne aircraft will need to take in order to accommodate the departures. The proportion of demand which is made up by such proposed departures increases as the horizon over which metering occurs gets larger. This study provides an initial analysis of the severity of this problem in a 400-500 nautical mile metering horizon and discusses potential solutions to accommodate these departures. The challenge is to smoothly incorporate departures with the airborne stream while not excessively delaying the departures.' In particular, three solutions are reviewed: (1) scheduling the departures at their proposed departure time; (2) not scheduling the departures in advance; and (3) scheduling the departures at some time in the future based on an estimated error in their proposed time. The first solution is to have McTMA to automatically schedule the departures at their proposed departure times. Since the proposed departure times are indicated in their flight times in advance, this method is the simplest, but studies have shown that these proposed times are often incorrect2 The second option is the current practice, which avoids these inaccuracies by only scheduling aircraft when a confirmed prediction of departure time is obtained from the tower of the departure airport. Lastly, McTMA can schedule the departures at a

  16. Precision Departure Release Capability (PDRC) Concept of Operations

    NASA Technical Reports Server (NTRS)

    Engelland, Shawn; Capps, Richard A.; Day, Kevin Brian

    2013-01-01

    After takeoff, aircraft must merge into en route (Center) airspace traffic flows which may be subject to constraints that create localized demandcapacity imbalances. When demand exceeds capacity Traffic Management Coordinators (TMCs) often use tactical departure scheduling to manage the flow of departures into the constrained Center traffic flow. Tactical departure scheduling usually involves use of a Call for Release (CFR) procedure wherein the Tower must call the Center TMC to coordinate a release time prior to allowing the flight to depart. In present-day operations release times are computed by the Center Traffic Management Advisor (TMA) decision support tool based upon manual estimates of aircraft ready time verbally communicated from the Tower to the Center. The TMA-computed release is verbally communicated from the Center back to the Tower where it is relayed to the Local controller as a release window that is typically three minutes wide. The Local controller will manage the departure to meet the coordinated release time window. Manual ready time prediction and verbal release time coordination are labor intensive and prone to inaccuracy. Also, use of release time windows adds uncertainty to the tactical departure process. Analysis of more than one million flights from January 2011 indicates that a significant number of tactically scheduled aircraft missed their en route slot due to ready time prediction uncertainty. Uncertainty in ready time estimates may result in missed opportunities to merge into constrained en route flows and lead to lost throughput. Next Generation Air Transportation System (NextGen) plans call for development of Tower automation systems capable of computing surface trajectory-based ready time estimates. NASA has developed the Precision Departure Release Capability (PDRC) concept that uses this technology to improve tactical departure scheduling by automatically communicating surface trajectory-based ready time predictions to the

  17. 78 FR 42805 - Nixon Presidential Historical Materials: Opening of Materials

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-17

    ... United States, National Archives at College Park, 8601 Adelphi Rd., College Park, Maryland 20740-6001... From the Federal Register Online via the Government Publishing Office NATIONAL ARCHIVES AND RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY:...

  18. The Geography of U.S. Presidential Elections.

    ERIC Educational Resources Information Center

    Archer, J. Clark; And Others

    1988-01-01

    Describes a statistical analysis of historical and recent presidential elections revealing enduring geographic patterns of partisan support and volatility. Discusses how they affect the Electoral College system and demand that a candidate build a geographic coalition. (CW)

  19. FEMP Focus - Special Issue 2006 - EPACT 2005 and Presidential Memo

    SciTech Connect

    2006-03-01

    Features information about Presidential Memorandum on Energy Conservation, Energy Policy Act 2005 Special Section, ESET FEMP Deploys Teams in Response to Natural Gas Concerns, Natural Gas Tips for Facility Managers, and more for federal agencies.

  20. Abrupt climate change in the computer: Is it real?

    PubMed Central

    Stocker, Thomas F.; Marchal, Olivier

    2000-01-01

    Models suggest that dramatic changes in the ocean circulation are responsible for abrupt climate changes during the last ice age and may possibly alter the relative climate stability of the last 10,000 years. PMID:10677468

  1. The Role of the Tropics in Abrupt Climate Changes

    SciTech Connect

    Fedorov, Alexey

    2013-12-07

    Topics addressed include: abrupt climate changes and ocean circulation in the tropics; what controls the ocean thermal structure in the tropics; a permanent El Niño in paleoclimates; the energetics of the tropical ocean.

  2. 3 CFR - Presidential Determination for the Lao People's Democratic Republic Under Section 2(b)(2) of the...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 3 The President 1 2010-01-01 2010-01-01 false Presidential Determination for the Lao People's Democratic Republic Under Section 2(b)(2) of the Export-Import Bank Act of 1945, as amended Presidential Documents Other Presidential Documents Presidential Determination No. 2009-21 of June 12, 2009 Presidential Determination for the Lao...

  3. Status Cataplecticus Precipitated by Abrupt Withdrawal of Venlafaxine

    PubMed Central

    Wang, Janice; Greenberg, Harly

    2013-01-01

    Status cataplecticus is a rare manifestation of narcolepsy with cataplexy episodes recurring for hours or days, without a refractory period, in the absence of emotional triggers. This case highlights a narcoleptic patient who developed status cataplecticus after abrupt withdrawal of venlafaxine. Citation: Wang J; Greenberg H. Status cataplecticus precipitated by abrupt withdrawal of venlafaxine. J Clin Sleep Med 2013;9(7):715-716. PMID:23853567

  4. Easing the Transition: Teaching Migrants in the Orderly Departure Program.

    ERIC Educational Resources Information Center

    Webster, Marian; Belmont, Susan

    1986-01-01

    Immigrants leaving Vietnam through the Orderly Departure Program in Bangkok, Thailand, experience stress and difficulties very different from those endured by refugees fleeing by land or boat. The cultural orientation program addresses their needs to assimilate their loss, gain equilibrium, and get resettlement guidance and information. These…

  5. Tick off to Take off: The Pre-Departure Guide

    ERIC Educational Resources Information Center

    Arthur, Erica

    2009-01-01

    "Tick Off to Take Off (TOTTO)" is an online pre-departure guide for UK undergraduates intending to study abroad. It aims to simplify the application process, centralise information, increase efficiency and improve retention rates. TOTTO responds to the changing climate surrounding study abroad in UK universities and offers one way to address calls…

  6. Presidential Science Advising from Roosevelt to Reagan

    NASA Astrophysics Data System (ADS)

    Herken, Gregg

    2004-05-01

    The relationship between American presidents and science has always been surprisingly idiosyncratic. Chief executives from Franklin Roosevelt to Ronald Reagan have adopted very different approaches to dealing with the scientific community. The early history of presidential science advising is the story of a few energetic individuals who sought to influence government policy when there was no established method for scientists to approach the White House. President Eisenhower created such a channel in 1957 with the President's Science Advisory Committee [PSAC]. Under Ike, advising the president became for the first time a systematic and formal enterprise for scientists. But the decades after Sputnik witnesses a steady waning of the importance of the president's scientists. This decline was accelerated by the Vietnam war and controversies over anti-ballistic missile defense and the supersonic transport, culminating in the abolition of PSAC by the Nixon administration in 1973. To some observers, science advising reached its nadir a decade later, with President Reagan's announcement of the Strategic Defense Initiative (SDI). The advent of "Star Wars" demonstrated the influence of a small, select group of politically-active scientists: a consultative process reminscient of the ad hoc situation pre-PSAC.

  7. New vegetation map of Castelporziano presidential estate

    NASA Astrophysics Data System (ADS)

    Della Rocca, Antonio B.; Pignatti, Sandro; Bianco, Pietro M.; Mugnoli, Stefano

    2003-03-01

    The 'Tenuta di Castelporziano' (Castelporziano Presidential Estate) is an important area for the study of Mediterranean coastal and dune ecosystems. The need of providing a new and detailed Vegetation Map rose for the environmental monitoring of that area and its efficient management. All activities were developed using remote sensing images acquired by a new 12 band DAEDALUS sensor, in the course of a specific monitoring aero-campaign organized by ENEA. The realization of the map, lasted one year, can be divided into two blocks: (1)remote sensing image processing methodologies, developed at the ENEA-Casaccia Research Center (Rome), by experts of Remote Sensing Department; and (2) 'in situ' work, realized by ecologists and botanical experts of University of Rome 'La Sapienza'. Image processing steps were organized as follows: (i) geometric correction and georeferencing of the images; (ii) classification; (iii) mosaicking; (iv) conversion into vector layer and editing. As concerns image processing, ERDAS/IMAGINE system was used, while ARC/INFO system was used for vector layers management and map printing. At the end of all activities the map accuracy was tested by a statistical procedure: the global accuracy was about of 88%. The map is integrated in a information system (SITAC), a GIS realized by ENEA.

  8. Abrupt changes in rainfall during the twentieth century

    NASA Astrophysics Data System (ADS)

    Narisma, G.; Foley, J.; Licker, R.; Ramankutty, N.

    2007-12-01

    A sudden change in climate is brought about by complex interactions in the climate system, including interactions between land and atmosphere, that can give rise to strong positive feedback mechanisms. Paleoclimatic studies have shown that abrupt climate changes have happened in the geologic past. Studies of future climate change under global warming scenarios indicate the possibility of the sudden collapse of the thermohaline circulation, which will have major implications for the climate of Europe. However, abrupt climatic changes are not events of the geologic past or a computer-simulated future: they have occurred in recent history and have had serious consequences on society and the environment. The prolonged Sahel drought in the late 1960s and the Dust Bowl of the 1930s are examples of abrupt climatic changes of the twentieth century. Apart from these events, however, there has been no systematic survey of recent climate history to determine the prevalence of abrupt climatic changes. Given the potential cost of these abrupt changes, there is a need to investigate historical records for evidence of other sudden climatic changes in the more recent past. Here we analyze the Climate Research Unit global historical rainfall observations (covering the years 1901-2000) using wavelet analysis to detect regions that have undergone large, sudden decreases in rainfall. We show that in the twentieth century, aside from the Sahel and the US midwest, at least 30 regions in the world have experienced sudden climatic changes. These events are statistically significant at the 99 percent level, are persistent for at least ten years, and most have magnitudes of change that are 10 percent lower than the climatological normal (1901-2000 rainfall average). We also illustrate some of the potential consequences of these abrupt changes and show that these events had major impacts on social and environmental conditions. Interestingly, these regions of abrupt precipitation changes are

  9. 76 FR 56969 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-15

    ... Procedures (44 FR 11034; February 26, 1979); and (3) does not warrant preparation of a regulatory evaluation... Minimums and Obstacle Departure Procedures; Miscellaneous Amendments AGENCY: Federal Aviation... Instrument Approach Procedures (SIAPs) and associated Takeoff Minimums and Obstacle Departure Procedures...

  10. 76 FR 30536 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-26

    ... Minimums and Obstacle Departure Procedures; Miscellaneous Amendments AGENCY: Federal Aviation... Standard Instrument Approach Procedures (SIAPs) and associated Takeoff Minimums and Obstacle Departure... commissioning of new navigational facilities, adding new obstacles, or changing air traffic requirements....

  11. Abrupt seasonal variation of the ITCZ and the Hadley circulation

    NASA Astrophysics Data System (ADS)

    Hu, Yongyun; Li, Dawei; Liu, Jiping

    2007-09-01

    Using Global Precipitation Climatology Project (GPCP) daily data, we show that the seasonal migration of the global zonal-mean intertropical convergence zone (ITCZ) is not smooth, but jumps from the winter hemisphere to the summer hemisphere. The abrupt migration is within 10 days. Detailed analyses reveal that the phenomenon of the abrupt seasonal migration of the ITCZ mainly exists over particular tropical domains, such as Indian Ocean, western and central Pacific, and South America, which gives the rise of the jump of the global zonal-mean ITCZ. Because the ITCZ constitutes the ascending branch of the Hadley circulation, we also examine whether there exists such an abrupt seasonal change in the Hadley circulation. It is found that the intensity of the Hadley cells evolves smoothly with time. However, the horizontal scales of the Hadley cells demonstrate abrupt seasonal changes, corresponding to the abrupt seasonal migration of the global ITCZ. The winter cell extends rapidly across the equator, while the summer cell rapidly narrows. This suggests that the solsticial cell is the dominant component of the Hadley circulation, and that the equinoctial symmetric pattern is ephemeral.

  12. 8 CFR 251.5 - Paper arrival and departure manifests for crew.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Paper arrival and departure manifests for... REGULATIONS ARRIVAL AND DEPARTURE MANIFESTS AND LISTS: SUPPORTING DOCUMENTS § 251.5 Paper arrival and... from the United States must submit arrival and departure manifests in a paper format in accordance...

  13. International policy implications of abrupt climate change scenarios

    SciTech Connect

    Molitor, M.R.

    1997-12-31

    New theoretical and empirical evidence supports the view that in the recent past [Holocene] abrupt climate changes occurred over very short [decadal] time periods. One leading possibility of future changes involves the North Atlantic Ocean conveyor that transfers warm surface waters from the equator to northern latitudes and helps maintain Europe`s climate. The predicted abrupt climate change scenario theorizes that the conveyor may be modified as a result of disruption of the thermohaline circulation driving North, Atlantic Deep Water. This would lead, the theory contends, to a rapid cooling of Europe`s climate. In light of the EPCC`s 1995 Second Assessment Report conclusion that there is a {open_quotes}discernible{close_quotes} human influence on the global climate system, there are many emerging questions concerning possible abrupt climate change scenarios.

  14. Sea-ice switches and abrupt climate change.

    PubMed

    Gildor, Hezi; Tziperman, Eli

    2003-09-15

    We propose that past abrupt climate changes were probably a result of rapid and extensive variations in sea-ice cover. We explain why this seems a perhaps more likely explanation than a purely thermohaline circulation mechanism. We emphasize that because of the significant influence of sea ice on the climate system, it seems that high priority should be given to developing ways for reconstructing high-resolution (in space and time) sea-ice extent for past climate-change events. If proxy data can confirm that sea ice was indeed the major player in past abrupt climate-change events, it seems less likely that such dramatic abrupt changes will occur due to global warming, when extensive sea-ice cover will not be present.

  15. Sea-ice switches and abrupt climate change.

    PubMed

    Gildor, Hezi; Tziperman, Eli

    2003-09-15

    We propose that past abrupt climate changes were probably a result of rapid and extensive variations in sea-ice cover. We explain why this seems a perhaps more likely explanation than a purely thermohaline circulation mechanism. We emphasize that because of the significant influence of sea ice on the climate system, it seems that high priority should be given to developing ways for reconstructing high-resolution (in space and time) sea-ice extent for past climate-change events. If proxy data can confirm that sea ice was indeed the major player in past abrupt climate-change events, it seems less likely that such dramatic abrupt changes will occur due to global warming, when extensive sea-ice cover will not be present. PMID:14558902

  16. Incorporating Active Runway Crossings in Airport Departure Scheduling

    NASA Technical Reports Server (NTRS)

    Gupta, Gautam; Malik, Waqar; Jung, Yoon C.

    2010-01-01

    A mixed integer linear program is presented for deterministically scheduling departure and ar rival aircraft at airport runways. This method addresses different schemes of managing the departure queuing area by treating it as first-in-first-out queues or as a simple par king area where any available aircraft can take-off ir respective of its relative sequence with others. In addition, this method explicitly considers separation criteria between successive aircraft and also incorporates an optional prioritization scheme using time windows. Multiple objectives pertaining to throughput and system delay are used independently. Results indicate improvement over a basic first-come-first-serve rule in both system delay and throughput. Minimizing system delay results in small deviations from optimal throughput, whereas minimizing throughput results in large deviations in system delay. Enhancements for computational efficiency are also presented in the form of reformulating certain constraints and defining additional inequalities for better bounds.

  17. A sharp upper bound for departure from normality

    SciTech Connect

    Lee, S.L.

    1993-08-01

    The departure from normality of a matrix is a real scalar that is impractical to compute if a matrix is large and its eigenvalues are unknown. A simple formula is presented for computing an upper bound for departure from normality in the Frobenius norm. This new upper bound is cheaper to compute than the upper bound derived by Henrici. Moreover, the new bound is sharp for Hermitian matrices, skew-Hermitian matrices and, in general, any matrix with eigenvalues that are horizontally or vertically aligned in the complex plane. In terms of applications, the new bound can be used in computing bounds for the spectral norm of matrix functions or bounds for the sensitivity of eigenvalues to matrix perturbations.

  18. 75 FR 42790 - Advisory Committee on Presidential Library-Foundation Partnerships.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ... RECORDS ADMINISTRATION Advisory Committee on Presidential Library-Foundation Partnerships. AGENCY: National Archives and Records Administration. ACTION: Renewal of Advisory Committee on Presidential Library... Library-Foundation Partnerships. In accordance with Office of Management and Budget (OMB) Circular...

  19. 78 FR 52531 - The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-23

    ... ADMINISTRATION The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meeting AGENCY: Office of Government-wide Policy, U.S. General Services Administration (GSA). ACTION: Meeting Notice. SUMMARY: The Presidential Commission on Election Administration (PCEA), a Federal...

  20. 78 FR 35272 - The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-12

    ... ADMINISTRATION The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meeting AGENCY: Office of Government-wide Policy, U.S. General Services Administration (GSA). ACTION: M eeting notice. SUMMARY: The Presidential Commission on Election Administration (PCEA), a Federal...

  1. 78 FR 38042 - The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meeting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-25

    ... ADMINISTRATION The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meeting; Correction AGENCY: Office of Government-wide Policy, U.S. General Services Administration (GSA). ACTION: Meeting notice; correction. SUMMARY: The Presidential Commission on Election Administration (PCEA),...

  2. 78 FR 55079 - The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-09

    ... ADMINISTRATION The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meetings AGENCY: Office of Government-wide Policy, U.S. General Services Administration (GSA). ACTION: Meeting notice. SUMMARY: The Presidential Commission on Election Administration (PCEA), a Federal...

  3. 78 FR 45200 - The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-26

    ... ADMINISTRATION The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meeting AGENCY: Office of Government-wide Policy, U.S. General Services Administration (GSA). ACTION: Meeting Notice. SUMMARY: The Presidential Commission on Election Administration (PCEA), a Federal...

  4. 78 FR 69416 - The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ... ADMINISTRATION The Presidential Commission on Election Administration (PCEA); Upcoming Public Advisory Meeting AGENCY: Office of Government-Wide Policy, U.S. General Services Administration (GSA). ACTION: Meeting Notice. SUMMARY: The Presidential Commission on Election Administration (PCEA), a Federal...

  5. A Consideration of Constraints on Aircraft Departure Operations

    NASA Technical Reports Server (NTRS)

    Darr, Stephen T.; Morello, Samuel A.; Shay, Richard F.; Lemos, Katherine A.; Jacobsen, Robert

    2009-01-01

    This paper presents a system-level perspective on the operational issues and constraints that limit departure capacity at large metropolitan airports in today's air transportation system. It examines the influence of constraints evident in en route airspace, in metroplex operations, and at individual airports from today's perspective and with a view toward future gate-to-cruise operations. Cross cutting organizational and technological challenges are discussed in relation to their importance in addressing the constraints.

  6. Revised Point of Departure Design Options for Nuclear Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Fittje, James E.; Schnitzler, Bruce G.; Borowoski, Stanley

    2015-01-01

    Four Revised Point of Departure NTR Engines were Designed and Analyzed using MCNP and NESS. All Four Engines Have Thermodynamically Closed Cycles at Nominal Chamber Pressures. 111 kilonewton (25 kip-force) Cermet Design Required Dedicated Heater Elements to Close the Cycle. Cermet Based Designs had Slightly Higher TW Ratios, but Required Substantially More U-235. NERVA Derived Criticality Limited Engine Could Operate at Lower Power and Thrust Levels Compared to the Criticality Limited Cermet Design.

  7. Optimal Integration of Departure and Arrivals in Terminal Airspace

    NASA Technical Reports Server (NTRS)

    Xue, Min; Zelinski, Shannon Jean

    2012-01-01

    Coordination of operations with spatially and temporally shared resources such as route segments, fixes, and runways improves the efficiency of terminal airspace management. Problems in this category include scheduling and routing, thus they are normally difficult to solve compared with pure scheduling problems. In order to reduce the computational time, a fast time algorithm formulation using a non-dominated sorting genetic algorithm (NSGA) was introduced in this work and applied to a test case based on existing literature. The experiment showed that new method can solve the whole problem in fast time instead of solving sub-problems sequentially with a window technique. The results showed a 60% or 406 second delay reduction was achieved by sharing departure fixes (more details on the comparison with MILP results will be presented in the final paper). Furthermore, the NSGA algorithm was applied to a problem in LAX terminal airspace, where interactions between 28% of LAX arrivals and 10% of LAX departures are resolved by spatial segregation, which may introduce unnecessary delays. In this work, spatial segregation, temporal segregation, and hybrid segregation were formulated using the new algorithm. Results showed that spatial and temporal segregation approaches achieved similar delay. Hybrid segregation introduced much less delay than the other two approaches. For a total of 9 interacting departures and arrivals, delay reduction varied from 4 minutes to 6.4 minutes corresponding flight time uncertainty from 0 to 60 seconds. Considering the amount of flights that could be affected, total annual savings with hybrid segregation would be significant.

  8. 36 CFR 1280.90 - What are the rules of conduct while visiting the Presidential libraries?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... while visiting the Presidential libraries? 1280.90 Section 1280.90 Parks, Forests, and Public Property... Apply for Use of Facilities in Presidential Libraries? § 1280.90 What are the rules of conduct while visiting the Presidential libraries? In addition to the rules in Subpart A, when visiting the museums...

  9. 77 FR 68153 - Advisory Committee on Presidential Library-Foundation Partnerships

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-15

    ... RECORDS ADMINISTRATION Advisory Committee on Presidential Library-Foundation Partnerships AGENCY: National... (NARA) announces a meeting of the Advisory Committee on Presidential Library-Foundation Partnerships. The meeting will be held to discuss the Presidential Library program and topics related to the...

  10. 36 CFR 1281.4 - What are the architectural and design standards for Presidential libraries?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and design standards for Presidential libraries? 1281.4 Section 1281.4 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES PRESIDENTIAL LIBRARY FACILITIES § 1281.4 What are the architectural and design standards for Presidential libraries? The Archivist...

  11. 36 CFR 1281.14 - What type of endowment is required for a Presidential library?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... required for a Presidential library? 1281.14 Section 1281.14 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES PRESIDENTIAL LIBRARY FACILITIES § 1281.14 What type of endowment is required for a Presidential library? (a) Endowment requirement—new libraries. The foundation...

  12. 77 FR 39613 - Presidential Determination on a U.S. Export Import Bank Transaction with Vietnam

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-03

    ...--Presidential Determination on a U.S. Export-Import Bank Transaction With Vietnam #0; #0; #0; Presidential... Presidential Determination on a U.S. Export Import Bank Transaction with Vietnam Memorandum for the Secretary of State Pursuant to section 2(b)(2)(D) of the Export Import Bank Act of 1945, as amended,...

  13. 36 CFR 1281.4 - What are the architectural and design standards for Presidential libraries?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and design standards for Presidential libraries? 1281.4 Section 1281.4 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES PRESIDENTIAL LIBRARY FACILITIES § 1281.4 What are the architectural and design standards for Presidential libraries? The Archivist...

  14. 36 CFR 1281.4 - What are the architectural and design standards for Presidential libraries?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and design standards for Presidential libraries? 1281.4 Section 1281.4 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES PRESIDENTIAL LIBRARY FACILITIES § 1281.4 What are the architectural and design standards for Presidential libraries? The Archivist...

  15. 36 CFR 1280.90 - What are the rules of conduct while visiting the Presidential libraries?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... while visiting the Presidential libraries? 1280.90 Section 1280.90 Parks, Forests, and Public Property... Apply for Use of Facilities in Presidential Libraries? § 1280.90 What are the rules of conduct while visiting the Presidential libraries? In addition to the rules in Subpart A, when visiting the museums...

  16. 36 CFR 1280.90 - What are the rules of conduct while visiting the Presidential libraries?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... while visiting the Presidential libraries? 1280.90 Section 1280.90 Parks, Forests, and Public Property... Apply for Use of Facilities in Presidential Libraries? § 1280.90 What are the rules of conduct while visiting the Presidential libraries? In addition to the rules in Subpart A, when visiting the museums...

  17. 36 CFR 1280.90 - What are the rules of conduct while visiting the Presidential libraries?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... while visiting the Presidential libraries? 1280.90 Section 1280.90 Parks, Forests, and Public Property... Apply for Use of Facilities in Presidential Libraries? § 1280.90 What are the rules of conduct while visiting the Presidential libraries? In addition to the rules in Subpart A, when visiting the museums...

  18. 36 CFR 1281.4 - What are the architectural and design standards for Presidential libraries?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... design standards for Presidential libraries? 1281.4 Section 1281.4 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES PRESIDENTIAL LIBRARY FACILITIES § 1281.4 What are the architectural and design standards for Presidential libraries? The Archivist is required by...

  19. 77 FR 74017 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-12

    ... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Office of the Assistant... Services (DHHS) is hereby giving notice that the Presidential Advisory Council on HIV/AIDS (PACHA) will... Health Assistant, Presidential Advisory Council on HIV/AIDS, Department of Health and Human Services,...

  20. 78 FR 19710 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-02

    ... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Department of Health and... Service (DHHS) is hereby giving notice that the Presidential Advisory Council on HIV/AIDS (PACHA) will..., Public Health Assistant, Presidential Advisory Council on HIV/AIDS, Department of Health and...

  1. 77 FR 6122 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-07

    ... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Office of the Assistant... Service (DHHS) is hereby giving notice that the Presidential Advisory Council on HIV/AIDS (PACHA) will... Manager, Presidential Advisory Council on HIV/AIDS, Department of Health and Human Services,...

  2. 26 CFR 702.9037-2 - Payments from the Presidential Primary Matching Payment Account.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 20 2011-04-01 2011-04-01 false Payments from the Presidential Primary Matching... THE TREASURY (CONTINUED) INTERNAL REVENUE PRACTICE PRESIDENTIAL PRIMARY MATCHING PAYMENT ACCOUNT § 702.9037-2 Payments from the Presidential Primary Matching Payment Account. (a) In general. Pursuant...

  3. 26 CFR 702.9037-2 - Payments from the Presidential Primary Matching Payment Account.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 20 2010-04-01 2010-04-01 false Payments from the Presidential Primary Matching... THE TREASURY (CONTINUED) INTERNAL REVENUE PRACTICE PRESIDENTIAL PRIMARY MATCHING PAYMENT ACCOUNT § 702.9037-2 Payments from the Presidential Primary Matching Payment Account. (a) In general. Pursuant...

  4. 26 CFR 702.9037-1 - Transfer of amounts to the Presidential Primary Matching Payment Account.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (Primary Account) only to the extent that there are amounts in the Presidential Election Campaign Fund... the Primary Account after October 31 following a presidential election will be returned to the Fund... presidential election. (b) Effective/applicability date. These regulations apply to the Primary Account on...

  5. 48 CFR 37.116-1 - Presidential $1 Coin Act of 2005.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Presidential $1 Coin Act... Presidential $1 Coin Act of 2005. This section implements Section 104 of the Presidential $1 Coin Act of 2005 (31 U.S.C. 5112(p)(1)), which seeks to remove barriers to the circulation of $1 coins. Section...

  6. 48 CFR 37.116-1 - Presidential $1 Coin Act of 2005.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Presidential $1 Coin Act... Presidential $1 Coin Act of 2005. This section implements Section 104 of the Presidential $1 Coin Act of 2005 (31 U.S.C. 5112(p)(1)), which seeks to remove barriers to the circulation of $1 coins. Section...

  7. 36 CFR 1280.92 - When are the Presidential library museums open to the public?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... individual facility you wish to visit for the hours of operation. See 36 CFR 1253.3 for Presidential Library contact information. All Presidential Library museums are closed on Thanksgiving, December 25, and January... 25. (b) See 36 CFR 1253.3 for the operating hours of the research rooms of the Presidential Libraries....

  8. 3 CFR - Presidential Determination on a U.S. Export-Import Bank Transaction With Vietnam

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Bank Transaction With Vietnam Presidential Documents Other Presidential Documents Presidential... With Vietnam Memorandum for the Secretary of State Pursuant to section 2(b)(2)(D) of the Export-Import...,890 to the Vietnam Post and Telecommunications Group, a wholly state-owned company, for the...

  9. 11 CFR 9037.1 - Payments of Presidential primary matching funds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Secretary in the case of a shortfall in the matching payment account. See 26 CFR 702.9037-1 and 702.9037-2. ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Payments of Presidential primary matching funds...: PRESIDENTIAL PRIMARY MATCHING FUND PAYMENTS AND REPORTING § 9037.1 Payments of Presidential primary...

  10. 26 CFR 702.9037-1 - Transfer of amounts to the Presidential Primary Matching Payment Account.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 20 2011-04-01 2011-04-01 false Transfer of amounts to the Presidential Primary..., DEPARTMENT OF THE TREASURY (CONTINUED) INTERNAL REVENUE PRACTICE PRESIDENTIAL PRIMARY MATCHING PAYMENT ACCOUNT § 702.9037-1 Transfer of amounts to the Presidential Primary Matching Payment Account. (a)...

  11. 11 CFR 9037.1 - Payments of Presidential primary matching funds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Secretary in the case of a shortfall in the matching payment account. See 26 CFR 702.9037-1 and 702.9037-2. ... 11 Federal Elections 1 2011-01-01 2011-01-01 false Payments of Presidential primary matching funds...: PRESIDENTIAL PRIMARY MATCHING FUND PAYMENTS AND REPORTING § 9037.1 Payments of Presidential primary...

  12. 36 CFR 1280.90 - What are the rules of conduct while visiting the Presidential libraries?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... while visiting the Presidential libraries? 1280.90 Section 1280.90 Parks, Forests, and Public Property... Apply for Use of Facilities in Presidential Libraries? § 1280.90 What are the rules of conduct while visiting the Presidential libraries? In addition to the rules in Subpart A, when visiting the museums...

  13. 36 CFR 1281.14 - What type of endowment is required for a Presidential library?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... required for a Presidential library? 1281.14 Section 1281.14 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES PRESIDENTIAL LIBRARY FACILITIES § 1281.14 What type of endowment is required for a Presidential library? (a) Endowment requirement—new libraries. The foundation...

  14. 36 CFR 1281.4 - What are the architectural and design standards for Presidential libraries?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and design standards for Presidential libraries? 1281.4 Section 1281.4 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NARA FACILITIES PRESIDENTIAL LIBRARY FACILITIES § 1281.4 What are the architectural and design standards for Presidential libraries? The Archivist...

  15. Abrupt Depletion Layer Approximation for the Metal Insulator Semiconductor Diode.

    ERIC Educational Resources Information Center

    Jones, Kenneth

    1979-01-01

    Determines the excess surface change carrier density, surface potential, and relative capacitance of a metal insulator semiconductor diode as a function of the gate voltage, using the precise questions and the equations derived with the abrupt depletion layer approximation. (Author/GA)

  16. Abrupt climate change and thermohaline circulation: mechanisms and predictability.

    PubMed

    Marotzke, J

    2000-02-15

    The ocean's thermohaline circulation has long been recognized as potentially unstable and has consequently been invoked as a potential cause of abrupt climate change on all timescales of decades and longer. However, fundamental aspects of thermohaline circulation changes remain poorly understood.

  17. Abrupt changes in the dynamics of quantum disentanglement

    SciTech Connect

    Lastra, F.; Romero, G.; Lopez, C. E.; Retamal, J. C.; Franca Santos, M.

    2007-06-15

    The evolution of the lower bound of entanglement proposed by Chen et al. [Phys. Rev. Lett. 95, 210501 (2005)] in high-dimensional bipartite systems under dissipation is studied. Discontinuities for the time derivative of this bound are found depending on the initial conditions for entangled states. These abrupt changes along the evolution of the entanglement bound appear as precursors of sudden death.

  18. Abrupt climate change and thermohaline circulation: mechanisms and predictability.

    PubMed

    Marotzke, J

    2000-02-15

    The ocean's thermohaline circulation has long been recognized as potentially unstable and has consequently been invoked as a potential cause of abrupt climate change on all timescales of decades and longer. However, fundamental aspects of thermohaline circulation changes remain poorly understood. PMID:10677464

  19. Mechanisms of abrupt climate change of the last glacial period

    NASA Astrophysics Data System (ADS)

    Clement, Amy C.; Peterson, Larry C.

    2008-12-01

    More than a decade ago, ice core records from Greenland revealed that the last glacial period was characterized by abrupt climate changes that recurred on millennial time scales. Since their discovery, there has been a large effort to determine whether these climate events were a global phenomenon or were just confined to the North Atlantic region and also to reveal the mechanisms that were responsible for them. In this paper, we review the available paleoclimate observations of abrupt change during the last glacial period in order to place constraints on possible mechanisms. Three different mechanisms are then reviewed: ocean thermohaline circulation, sea ice feedbacks, and tropical processes. Each mechanism is tested for its ability to explain the key features of the observations, particularly with regard to the abruptness, millennial recurrence, and geographical extent of the observed changes. It is found that each of these mechanisms has explanatory strengths and weaknesses, and key areas in which progress could be made in improving the understanding of their long-term behavior, both from observational and modeling approaches, are suggested. Finally, it is proposed that a complete understanding of the mechanisms of abrupt change requires inclusion of processes at both low and high latitudes, as well as the potential for feedbacks between them. Some suggestions for experimental approaches to test for such feedbacks with coupled climate models are given.

  20. 5 CFR 317.703 - Guaranteed reinstatement: Presidential appointees.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the SES. (3) The agency being directed to take the reinstatement action is responsible for assigning... space authority to the agency. (5) When a Presidential appointee tenders his or her resignation... appointee without an order from OPM directing such action. (3) The agency is responsible for assigning...

  1. Foreign Policy News in the 1980 Presidential Election Campaign.

    ERIC Educational Resources Information Center

    Stovall, James Glen

    A survey was conducted to determine the extent and content of newspaper coverage of foreign policy issues in the 1980 United States presidential campaign. Fifty daily newspapers from every region of the country were selected randomly based on circulation. A list of 757 news events was divided into party and nonparty events, and the party events…

  2. 77 FR 61791 - System of Records; Presidential Management Fellows Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-11

    ... hosting and backup facilities is encrypted utilizing data at rest encryption technologies. A complete data... data base of PMF participant information will be destroyed when no longer needed for administrative... notice. In addition, Presidential Management Fellows Program data formerly collected by the Office...

  3. Challenges in an Aging Society: Presidential Address to APPAM

    ERIC Educational Resources Information Center

    Swartz, Katherine

    2010-01-01

    The United States is at a critical crossroads in its history right now. The public policy problems that the people are facing are complex and interrelated, and the demographic changes that are about to significantly change their country are not well understood by large numbers of people. In this presidential address to the Association for Public…

  4. Perception of News Bias in 1972 Presidential Campaign.

    ERIC Educational Resources Information Center

    Hofstetter, C. Richard

    1979-01-01

    Interviews with 1,034 respondents shortly before the 1972 presidential election, and with 701 of these respondents shortly after the election, revealed that a small proportion perceived political bias in television news, a larger proportion perceived biases in newspaper reporting, and the vast majority saw no political bias in either medium. (GT)

  5. Undergraduate Chemistry Education: Report of an ACS Presidential Symposium

    ERIC Educational Resources Information Center

    Polik, William F.

    2006-01-01

    The American Chemical Society (ACS) Presidential Symposium, Envisioning Undergraduate Chemistry Education in 2015 was organized by the ACS Committee on Professional Training (CPT), in response to the challenge to envision the chemistry enterprise in 2015. The need for more diverse role models at all levels is emphasized, including high school…

  6. Campaign Policies, Broadcasters, and the Presidential Election of 1924.

    ERIC Educational Resources Information Center

    Benjamin, Louise M.

    The policies initiated by broadcasters for campaign coverage during the 1924 presidential election influenced the treatment of political candidates on the air and helped set the stage for inclusion of the equal opportunities clause in the Radio Act of 1927. AT&T, RCA, and General Electric formed policies to treat candidates fairly in allocating…

  7. Flip-Flopping, Presidential Politics, and Abraham Lincoln

    ERIC Educational Resources Information Center

    Neumann, Dave

    2012-01-01

    The American public can count on a few things during the presidential election season. First, candidates will take a moral high ground and forswear mudslinging. Before long however, they will proceed to engage in nasty accusations against their opponents. A vibrant democracy ought to welcome carefully thought-out views that, when intentionally…

  8. Presidential Inaugurations: Planning for More than Pomp and Circumstance.

    ERIC Educational Resources Information Center

    Viola, Joy Winkie

    This publication covers the fundamentals of planning a college or university presidential inauguration. The guide's 10 chapters are based in part on a survey of colleges and universities that appointed new presidents between January 1990 and January 1992. The first chapter offers five rules for "getting your act together": you should have started…

  9. The 2012 NCTE Presidential Address: Literacy, Rhetoric, Education, Democracy

    ERIC Educational Resources Information Center

    Gilyard, Keith

    2013-01-01

    This article presents the text of Keith Gilyard's presidential address, delivered at the National Council of Teachers of English (NCTE) Annual Convention in Las Vegas, Nevada, on November 18, 2012. In his address he proposes several core elements that he believes will instrumentally improve the education system in the United States: a rich…

  10. Power Indices and U.S. Presidential Elections

    ERIC Educational Resources Information Center

    Colen, Yong S.; Navaratna, Channa; Colen, Jung; Kim, Jinho

    2012-01-01

    The 2012 U.S. presidential election is the perfect opportunity to present a timely civics lesson on how a U.S. president is elected. More important, it offers opportunities for students to reason mathematically about election issues--for example, about how much time and resources the candidates should invest in particular states. The results of…

  11. Presidential Leadership for Prevention. E-Fact Sheet

    ERIC Educational Resources Information Center

    Higher Education Center for Alcohol, Drug Abuse, and Violence Prevention, 2010

    2010-01-01

    Most of the colleges and universities that have received U.S. Department of Education Models of Exemplary, Effective, and Promising Alcohol or Other Drug Abuse Prevention Programs on College Campuses grants credit strong presidential leadership for the success of their prevention efforts. With many colleges and universities currently facing budget…

  12. The Presidency and Presidential Elections in the Elementary Classroom

    ERIC Educational Resources Information Center

    Haas, Mary E.

    2004-01-01

    This article describes how the author has found that very few lesson plans help teach about the presidency or about presidential elections at the primary level and only a few research studies about what elementary students know or teachers teach about the presidency and elections. The author provides directions and a short summary of a series of…

  13. The Presidential Address 2014. Teaching and Learning: The Long View

    ERIC Educational Resources Information Center

    Roberts, Alice

    2014-01-01

    This article presents the transcript of the Presidential Address delivered to the Association for Science Education Annual Conference held at the University of Birmingham in January 2014. In her address, Alice Roberts traces the evolution of various features that are often thought to make humans different from other animals. Examples such as…

  14. Presidential Spouses: Worth Taking Seriously, and Worth Paying

    ERIC Educational Resources Information Center

    Moser, Kate

    2008-01-01

    Mrs. Deborah J. Cofer is one of many presidential spouses who balk at the thought of being paid for their work--whether because they relish the freedom to take a night off or because they think of it as a natural part of their relationships with their partners. Mrs. Cofer believes that their mission is to enhance students' lives and they do not…

  15. Racism and the Conspiracy of Silence: Presidential Address

    ERIC Educational Resources Information Center

    Sue, Derald Wing

    2005-01-01

    This presidential address focuses on a specific and daunting assumption about racism that many find disturbing--a belief that no one born and raised in the United States is free from inheriting the racial biases of their forebears. It states explicitly that it is impossible for anyone to not to have racist, sexist, and homophobic attitudes,…

  16. The Presidential Commission on the Human Immunodeficiency Virus Epidemic Report.

    ERIC Educational Resources Information Center

    Presidential Commission on the Human Immunodeficiency Virus Epidemic, Washington, DC.

    This document presents findings of the Presidential Commission on the Human Immunodeficiency Virus (HIV) epidemic. The executive summary lists 20 major findings and recommendations which together comprise a comprehensive national strategy for managing the HIV epidemic. The commission recommends: (1) replacement of the obsolete term "AIDS"…

  17. A Value Analysis of the 1980 Presidential Debate.

    ERIC Educational Resources Information Center

    Hochel, Sandra

    Although Democrat Jimmy Carter and Republican Ronald Reagan appealed to many of the same basic American values in the 1980 presidential campaign debate, there were some subtle but major differences in their value appeals. Other than attempting to convince his audience that his policies had been and would be successful and that Reagan's policies…

  18. Who Will Win?: Predicting the Presidential Election Using Linear Regression

    ERIC Educational Resources Information Center

    Lamb, John H.

    2007-01-01

    This article outlines a linear regression activity that engages learners, uses technology, and fosters cooperation. Students generated least-squares linear regression equations using TI-83 Plus[TM] graphing calculators, Microsoft[C] Excel, and paper-and-pencil calculations using derived normal equations to predict the 2004 presidential election.…

  19. A Study of the Presidential Internships in Science and Engineering.

    ERIC Educational Resources Information Center

    Cater, Charles Edward; Korsmo, Thomas Brock

    A survey of scientists and engineers who participated in the Presidential Internships in Science and Engineering Program was conducted by a questionnaire to determine the effectiveness of the program in meeting its objectives and to identify some of the characteristics of the interns. The report summarizes responses to each question and recommends…

  20. For Overheated Viewers of Presidential Race: 'De-Escalate First'

    MedlinePlus

    ... Preidt Wednesday, October 19, 2016 WEDNESDAY, Oct. 19, 2016 (HealthDay News) -- The bitter U.S. presidential race has led to heated arguments among many ... long run." And share your concerns about the election with family and ... (c) 2016 HealthDay . All rights reserved. News stories are provided ...

  1. Presidential Leadership: Moral Leadership in the New Millennium.

    ERIC Educational Resources Information Center

    Corrigan, Robert A.

    2002-01-01

    Discusses the opportunities college and university presidential leaders have to contribute the resources of their institutions to public service. Leaders in higher education must keep the balance between free speech and civility and maintain the small world that is the university as a model of what the greater world should be. (SLD)

  2. Optimal Integration of Departures and Arrivals in Terminal Airspace

    NASA Technical Reports Server (NTRS)

    Xue, Min; Zelinski, Shannon Jean

    2013-01-01

    Coordination of operations with spatially and temporally shared resources, such as route segments, fixes, and runways, improves the efficiency of terminal airspace management. Problems in this category are, in general, computationally difficult compared to conventional scheduling problems. This paper presents a fast time algorithm formulation using a non-dominated sorting genetic algorithm (NSGA). It was first applied to a test problem introduced in existing literature. An experiment with a test problem showed that new methods can solve the 20 aircraft problem in fast time with a 65% or 440 second delay reduction using shared departure fixes. In order to test its application in a more realistic and complicated problem, the NSGA algorithm was applied to a problem in LAX terminal airspace, where interactions between 28% of LAX arrivals and 10% of LAX departures are resolved by spatial separation in current operations, which may introduce unnecessary delays. In this work, three types of separations - spatial, temporal, and hybrid separations - were formulated using the new algorithm. The hybrid separation combines both temporal and spatial separations. Results showed that although temporal separation achieved less delay than spatial separation with a small uncertainty buffer, spatial separation outperformed temporal separation when the uncertainty buffer was increased. Hybrid separation introduced much less delay than both spatial and temporal approaches. For a total of 15 interacting departures and arrivals, when compared to spatial separation, the delay reduction of hybrid separation varied between 11% or 3.1 minutes and 64% or 10.7 minutes corresponding to an uncertainty buffer from 0 to 60 seconds. Furthermore, as a comparison with the NSGA algorithm, a First-Come-First-Serve based heuristic method was implemented for the hybrid separation. Experiments showed that the results from the NSGA algorithm have 9% to 42% less delay than the heuristic method with varied

  3. A Human-in-the Loop Evaluation of a Coordinated Arrival Departure Scheduling Operations for Managing Departure Delays at LaGuardia Airport

    NASA Technical Reports Server (NTRS)

    Lee, Paul U.; Smith, Nancy M.; Bienert, Nancy; Brasil, Connie; Buckley, Nathan; Chevalley, Eric; Homola, Jeffrey; Omar, Faisal; Parke, Bonny; Yoo, Hyo-Sang

    2016-01-01

    LaGuardia (LGA) departure delay was identified by the stakeholders and subject matter experts as a significant bottleneck in the New York metropolitan area. Departure delay at LGA is primarily due to dependency between LGA's arrival and departure runways: LGA departures cannot begin takeoff until arrivals have cleared the runway intersection. If one-in one-out operations are not maintained and a significant arrival-to-departure imbalance occurs, the departure backup can persist through the rest of the day. At NASA Ames Research Center, a solution called "Departure-sensitive Arrival Spacing" (DSAS) was developed to maximize the departure throughput without creating significant delays in the arrival traffic. The concept leverages a Terminal Sequencing and Spacing (TSS) operations that create and manage the arrival schedule to the runway threshold and added an interface enhancement to the traffic manager's timeline to provide the ability to manually adjust inter-arrival spacing to build precise gaps for multiple departures between arrivals. A more complete solution would include a TSS algorithm enhancement that could automatically build these multi-departure gaps. With this set of capabilities, inter-arrival spacing could be controlled for optimal departure throughput. The concept was prototyped in a human-in-the- loop (HITL) simulation environment so that operational requirements such as coordination procedures, timing and magnitude of TSS schedule adjustments, and display features for Tower, TRACON and Traffic Management Unit could be determined. A HITL simulation was conducted in August 2014 to evaluate the concept in terms of feasibility, controller workload impact, and potential benefits. Three conditions were tested, namely a Baseline condition without scheduling, TSS condition that schedules the arrivals to the runway threshold, and TSS+DSAS condition that adjusts the arrival schedule to maximize the departure throughput. The results showed that during high

  4. Abruptly autofocusing terahertz waves with meta-hologram.

    PubMed

    He, Jingwen; Wang, Sen; Xie, Zhenwei; Ye, Jiasheng; Wang, Xinke; Kan, Qiang; Zhang, Yan

    2016-06-15

    An abruptly autofocusing ring-Airy beam is demonstrated in the terahertz (THz) waveband with a meta-hologram. The designed meta-hologram is composed of gold C-shaped slot antennas, which can realize both phase and amplitude modulation of the incident THz wave. A THz holographic imaging system is utilized to measure the generated ring-Airy beam; an abrupt focus following a parabolic trajectory is subsequently observed. THz ring-Airy beams with different parameters are also generated and investigated. This method can be expanded to other wavebands, such as the visible band, for which the meta-hologram can replace traditional computer-generated holography to avoid undesirable multiple diffraction orders.

  5. Abruptly autofocusing terahertz waves with meta-hologram.

    PubMed

    He, Jingwen; Wang, Sen; Xie, Zhenwei; Ye, Jiasheng; Wang, Xinke; Kan, Qiang; Zhang, Yan

    2016-06-15

    An abruptly autofocusing ring-Airy beam is demonstrated in the terahertz (THz) waveband with a meta-hologram. The designed meta-hologram is composed of gold C-shaped slot antennas, which can realize both phase and amplitude modulation of the incident THz wave. A THz holographic imaging system is utilized to measure the generated ring-Airy beam; an abrupt focus following a parabolic trajectory is subsequently observed. THz ring-Airy beams with different parameters are also generated and investigated. This method can be expanded to other wavebands, such as the visible band, for which the meta-hologram can replace traditional computer-generated holography to avoid undesirable multiple diffraction orders. PMID:27304289

  6. The role of the thermohaline circulation in abrupt climate change.

    PubMed

    Clark, Peter U; Pisias, Nicklas G; Stocker, Thomas F; Weaver, Andrew J

    2002-02-21

    The possibility of a reduced Atlantic thermohaline circulation in response to increases in greenhouse-gas concentrations has been demonstrated in a number of simulations with general circulation models of the coupled ocean-atmosphere system. But it remains difficult to assess the likelihood of future changes in the thermohaline circulation, mainly owing to poorly constrained model parameterizations and uncertainties in the response of the climate system to greenhouse warming. Analyses of past abrupt climate changes help to solve these problems. Data and models both suggest that abrupt climate change during the last glaciation originated through changes in the Atlantic thermohaline circulation in response to small changes in the hydrological cycle. Atmospheric and oceanic responses to these changes were then transmitted globally through a number of feedbacks. The palaeoclimate data and the model results also indicate that the stability of the thermohaline circulation depends on the mean climate state.

  7. Recommended Experimental Procedures for Evaluation of Abrupt Wing Stall Characteristics

    NASA Technical Reports Server (NTRS)

    Capone, F. J.; Hall, R. M.; Owens, D. B.; Lamar, J. E.; McMillin, S. N.

    2003-01-01

    This paper presents a review of the experimental program under the Abrupt Wing Stall (AWS) Program. Candidate figures of merit from conventional static tunnel tests are summarized and correlated with data obtained in unique free-to-roll tests. Where possible, free-to-roll results are also correlated with flight data. Based on extensive studies of static experimental figures of merit in the Abrupt Wing Stall Program for four different aircraft configurations, no one specific figure of merit consistently flagged a warning of potential lateral activity when actual activity was seen to occur in the free-to-roll experiments. However, these studies pointed out the importance of measuring and recording the root mean square signals of the force balance.

  8. [Traumatic abruption of the placenta with disseminated intravascular coagulation].

    PubMed

    Benz, R; Malär, A-U; Benz-Wörner, J; Scherer, M; Hodel, M; Gähler, A; Haberthür, C; Konrad, C

    2012-10-01

    Trauma in pregnancy is infrequent and a systematic primary strategy constitutes a real challenge for the interdisciplinary team. With a high fetal mortality rate and a substantial maternal mortality rate traumatic placental abruption is a severe emergency which every anesthetist should be aware of. After hemodynamic stabilization of the mother and control of the viability of the fetus the therapy of traumatic placental abruption consists mostly of an immediate caesarean section. Coagulopathy by depletion of coagulation factors as well as disseminated intravascular coagulation (DIC) have to be expected and consequently a massive blood loss must be anticipated. Thrombelastography provides assistance for fast differential diagnosis and goal-directed treatment of the disturbed sections of the coagulation cascade.

  9. The role of the thermohaline circulation in abrupt climate change.

    PubMed

    Clark, Peter U; Pisias, Nicklas G; Stocker, Thomas F; Weaver, Andrew J

    2002-02-21

    The possibility of a reduced Atlantic thermohaline circulation in response to increases in greenhouse-gas concentrations has been demonstrated in a number of simulations with general circulation models of the coupled ocean-atmosphere system. But it remains difficult to assess the likelihood of future changes in the thermohaline circulation, mainly owing to poorly constrained model parameterizations and uncertainties in the response of the climate system to greenhouse warming. Analyses of past abrupt climate changes help to solve these problems. Data and models both suggest that abrupt climate change during the last glaciation originated through changes in the Atlantic thermohaline circulation in response to small changes in the hydrological cycle. Atmospheric and oceanic responses to these changes were then transmitted globally through a number of feedbacks. The palaeoclimate data and the model results also indicate that the stability of the thermohaline circulation depends on the mean climate state. PMID:11859359

  10. Ultra-wideband horn antenna with abrupt radiator

    DOEpatents

    McEwan, Thomas E.

    1998-01-01

    An ultra-wideband horn antenna transmits and receives impulse waveforms for short-range radars and impulse time-of flight systems. The antenna reduces or eliminates various sources of close-in radar clutter, including pulse dispersion and ringing, sidelobe clutter, and feedline coupling into the antenna. Dispersion is minimized with an abrupt launch point radiator element; sidelobe and feedline coupling are minimized by recessing the radiator into a metallic horn. Low frequency cut-off associated with a horn is extended by configuring the radiator drive impedance to approach a short circuit at low frequencies. A tapered feed plate connects at one end to a feedline, and at the other end to a launcher plate which is mounted to an inside wall of the horn. The launcher plate and feed plate join at an abrupt edge which forms the single launch point of the antenna.

  11. Ultra-wideband horn antenna with abrupt radiator

    DOEpatents

    McEwan, T.E.

    1998-05-19

    An ultra-wideband horn antenna transmits and receives impulse waveforms for short-range radars and impulse time-of flight systems. The antenna reduces or eliminates various sources of close-in radar clutter, including pulse dispersion and ringing, sidelobe clutter, and feedline coupling into the antenna. Dispersion is minimized with an abrupt launch point radiator element; sidelobe and feedline coupling are minimized by recessing the radiator into a metallic horn. Low frequency cut-off associated with a horn is extended by configuring the radiator drive impedance to approach a short circuit at low frequencies. A tapered feed plate connects at one end to a feedline, and at the other end to a launcher plate which is mounted to an inside wall of the horn. The launcher plate and feed plate join at an abrupt edge which forms the single launch point of the antenna. 8 figs.

  12. Effect of Departure Delays on Manned Mars Mission Selection

    NASA Technical Reports Server (NTRS)

    Desai, Prasun N.; Tartabini, Paul V.

    1995-01-01

    This study determines the effect on the initial mass in low Earth orbit (IMLEO) of delaying departure from Mars and Earth by 5, 15, and 30 days, once a nominal mission to Mars has been selected. Additionally, the use of a deep-space maneuver (DSM) is considered in order to alleviate the IMLEO penalties. Three different classes of missions are analyzed, using chemical and nuclear thermal propulsion systems in the 2000-2025 time frame: opposition, conjunction, and fast-transfer conjunction. The results indicate that Mars and Earth delays can lead to large IMLEO penalties. Opposition and fast-transfer conjunction-class missions have the highest IMLEO penalties, upwards of 432.4 and 1977.3 metric tons (mt), respectively. Conjunction-class missions, on the other hand, tend to be insensitive to Mars and Earth delays, having IMLEO penalties under 103.5 mt. As expected, nuclear thermal propulsion had significantly lower IMLEO penalties than chemical propulsion. The use of a DSM does not significantly reduce the penalties. The results of this study can enable mission designers to incorporate the influence of off-nominal departure conditions of the interplanetary trajectory in the overall conceptual design of a Mars transfer vehicle.

  13. Response of seafloor ecosystems to abrupt global climate change

    PubMed Central

    Moffitt, Sarah E.; Hill, Tessa M.; Roopnarine, Peter D.; Kennett, James P.

    2015-01-01

    Anthropogenic climate change is predicted to decrease oceanic oxygen (O2) concentrations, with potentially significant effects on marine ecosystems. Geologically recent episodes of abrupt climatic warming provide opportunities to assess the effects of changing oxygenation on marine communities. Thus far, this knowledge has been largely restricted to investigations using Foraminifera, with little being known about ecosystem-scale responses to abrupt, climate-forced deoxygenation. We here present high-resolution records based on the first comprehensive quantitative analysis, to our knowledge, of changes in marine metazoans (Mollusca, Echinodermata, Arthropoda, and Annelida; >5,400 fossils and trace fossils) in response to the global warming associated with the last glacial to interglacial episode. The molluscan archive is dominated by extremophile taxa, including those containing endosymbiotic sulfur-oxidizing bacteria (Lucinoma aequizonatum) and those that graze on filamentous sulfur-oxidizing benthic bacterial mats (Alia permodesta). This record, from 16,100 to 3,400 y ago, demonstrates that seafloor invertebrate communities are subject to major turnover in response to relatively minor inferred changes in oxygenation (>1.5 to <0.5 mL⋅L−1 [O2]) associated with abrupt (<100 y) warming of the eastern Pacific. The biotic turnover and recovery events within the record expand known rates of marine biological recovery by an order of magnitude, from <100 to >1,000 y, and illustrate the crucial role of climate and oceanographic change in driving long-term successional changes in ocean ecosystems. PMID:25825727

  14. Response of seafloor ecosystems to abrupt global climate change

    NASA Astrophysics Data System (ADS)

    Moffitt, Sarah E.; Hill, Tessa M.; Roopnarine, Peter D.; Kennett, James P.

    2015-04-01

    Anthropogenic climate change is predicted to decrease oceanic oxygen (O2) concentrations, with potentially significant effects on marine ecosystems. Geologically recent episodes of abrupt climatic warming provide opportunities to assess the effects of changing oxygenation on marine communities. Thus far, this knowledge has been largely restricted to investigations using Foraminifera, with little being known about ecosystem-scale responses to abrupt, climate-forced deoxygenation. We here present high-resolution records based on the first comprehensive quantitative analysis, to our knowledge, of changes in marine metazoans (Mollusca, Echinodermata, Arthropoda, and Annelida; >5,400 fossils and trace fossils) in response to the global warming associated with the last glacial to interglacial episode. The molluscan archive is dominated by extremophile taxa, including those containing endosymbiotic sulfur-oxidizing bacteria (Lucinoma aequizonatum) and those that graze on filamentous sulfur-oxidizing benthic bacterial mats (Alia permodesta). This record, from 16,100 to 3,400 y ago, demonstrates that seafloor invertebrate communities are subject to major turnover in response to relatively minor inferred changes in oxygenation (>1.5 to <0.5 mLṡL-1 [O2]) associated with abrupt (<100 y) warming of the eastern Pacific. The biotic turnover and recovery events within the record expand known rates of marine biological recovery by an order of magnitude, from <100 to >1,000 y, and illustrate the crucial role of climate and oceanographic change in driving long-term successional changes in ocean ecosystems.

  15. Response of seafloor ecosystems to abrupt global climate change.

    PubMed

    Moffitt, Sarah E; Hill, Tessa M; Roopnarine, Peter D; Kennett, James P

    2015-04-14

    Anthropogenic climate change is predicted to decrease oceanic oxygen (O2) concentrations, with potentially significant effects on marine ecosystems. Geologically recent episodes of abrupt climatic warming provide opportunities to assess the effects of changing oxygenation on marine communities. Thus far, this knowledge has been largely restricted to investigations using Foraminifera, with little being known about ecosystem-scale responses to abrupt, climate-forced deoxygenation. We here present high-resolution records based on the first comprehensive quantitative analysis, to our knowledge, of changes in marine metazoans (Mollusca, Echinodermata, Arthropoda, and Annelida; >5,400 fossils and trace fossils) in response to the global warming associated with the last glacial to interglacial episode. The molluscan archive is dominated by extremophile taxa, including those containing endosymbiotic sulfur-oxidizing bacteria (Lucinoma aequizonatum) and those that graze on filamentous sulfur-oxidizing benthic bacterial mats (Alia permodesta). This record, from 16,100 to 3,400 y ago, demonstrates that seafloor invertebrate communities are subject to major turnover in response to relatively minor inferred changes in oxygenation (>1.5 to <0.5 mL⋅L(-1) [O2]) associated with abrupt (<100 y) warming of the eastern Pacific. The biotic turnover and recovery events within the record expand known rates of marine biological recovery by an order of magnitude, from <100 to >1,000 y, and illustrate the crucial role of climate and oceanographic change in driving long-term successional changes in ocean ecosystems.

  16. A Rare Cause of Placental Abruption: Uterine Torsion.

    PubMed

    Ulu, Ipek; Güneş, Muhammed Siraç; Kiran, Gürkan; Gülşen, Mehmet Serdar

    2016-01-01

    Uterine torsion is defined as a rotation on its long axis and it is a dangerous, unexpected obstetric emergency. We report a case of uterine torsion at 32 weeks of gestation in a singleton pregnancy. A 37-year-old woman with multiple prior cesarean deliveries referred to emergency unit of our hospital at 32 weeks of gestation with severe abdominal pain and mild vaginal bleeding. Ultrasonography showed a single fetus in vertex position, with a normal amniotic fluid. Fetal biometer was appropriate for 32 weeks of gestation. Placental location was anterior with a subchorionic hypoechogenic small area which was suspected to be a sign of placental abruption. An emergency cesarean section was performed under general anesthesia. The 180° uterine torsion was diagnosed and it was not possible to perform detorsion of the gravid uterus by exteriorization by pfannenstiel incision. Posterior hysterotomy was performed and a male baby of 1830 grams weight was delivered. The newborn was transported to Neonatal Intensive Care Unit (NICU) of another hospital and discharged within two weeks. Patient recovered well and was discharged on second postoperation day. Uterine torsion is a very rare and life threatening situation. In unexpected cases posterior low transuerse hysterotomy is generally performed and it is suggested as a safe choice when detorsion was not accomplished. It is not easy to keep in mind the possibility of uterine torsion in cases of abdominal pain during pregnancy. Because it generally causes abruption, management of abruption is vitally important to prevent fetal mortality. PMID:26894131

  17. Response of seafloor ecosystems to abrupt global climate change.

    PubMed

    Moffitt, Sarah E; Hill, Tessa M; Roopnarine, Peter D; Kennett, James P

    2015-04-14

    Anthropogenic climate change is predicted to decrease oceanic oxygen (O2) concentrations, with potentially significant effects on marine ecosystems. Geologically recent episodes of abrupt climatic warming provide opportunities to assess the effects of changing oxygenation on marine communities. Thus far, this knowledge has been largely restricted to investigations using Foraminifera, with little being known about ecosystem-scale responses to abrupt, climate-forced deoxygenation. We here present high-resolution records based on the first comprehensive quantitative analysis, to our knowledge, of changes in marine metazoans (Mollusca, Echinodermata, Arthropoda, and Annelida; >5,400 fossils and trace fossils) in response to the global warming associated with the last glacial to interglacial episode. The molluscan archive is dominated by extremophile taxa, including those containing endosymbiotic sulfur-oxidizing bacteria (Lucinoma aequizonatum) and those that graze on filamentous sulfur-oxidizing benthic bacterial mats (Alia permodesta). This record, from 16,100 to 3,400 y ago, demonstrates that seafloor invertebrate communities are subject to major turnover in response to relatively minor inferred changes in oxygenation (>1.5 to <0.5 mL⋅L(-1) [O2]) associated with abrupt (<100 y) warming of the eastern Pacific. The biotic turnover and recovery events within the record expand known rates of marine biological recovery by an order of magnitude, from <100 to >1,000 y, and illustrate the crucial role of climate and oceanographic change in driving long-term successional changes in ocean ecosystems. PMID:25825727

  18. U.S. Presidential Candidate camps debate sciences issues

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2000-10-01

    While budget surpluses, social security, and tax cut proposals have been major focuses during the U.S. presidential campaign between Texas Governor George W Bush and Vice President Al Gore, the candidates also have staked out a number of important issues related to Earth sciences and the environment. Two recent debates between representatives of the Bush and Gore camps have helped to clarify these positions. The Washington Science Policy Alliance presented a candidates forum on science and technology policy on October 5 at the American Association for the Advancement of Science (AAAS), in Washington, D.C. On September 26, the non-profit National Environmental Policy Institute (NEPI) held a debate on presidential politics and the environment at the National Press Club, also in Washington, D.C.

  19. Software Tools to Support Research on Airport Departure Planning

    NASA Technical Reports Server (NTRS)

    Carr, Francis; Evans, Antony; Feron, Eric; Clarke, John-Paul

    2003-01-01

    A simple, portable and useful collection of software tools has been developed for the analysis of airport surface traffic. The tools are based on a flexible and robust traffic-flow model, and include calibration, validation and simulation functionality for this model. Several different interfaces have been developed to help promote usage of these tools, including a portable Matlab(TM) implementation of the basic algorithms; a web-based interface which provides online access to automated analyses of airport traffic based on a database of real-world operations data which covers over 250 U.S. airports over a 5-year period; and an interactive simulation-based tool currently in use as part of a college-level educational module. More advanced applications for airport departure traffic include taxi-time prediction and evaluation of "windowing" congestion control.

  20. Revised Point of Departure Design Options for Nuclear Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Fittje, James E.; Borowski, Stanley K.; Schnitzler, Bruce

    2015-01-01

    In an effort to further refine potential point of departure nuclear thermal rocket engine designs, four proposed engine designs representing two thrust classes and utilizing two different fuel matrix types are designed and analyzed from both a neutronics and thermodynamic cycle perspective. Two of these nuclear rocket engine designs employ a tungsten and uranium dioxide cermet (ceramic-metal) fuel with a prismatic geometry based on the ANL-200 and the GE-710, while the other two designs utilize uranium-zirconium-carbide in a graphite composite fuel and a prismatic fuel element geometry developed during the Rover/NERVA Programs. Two engines are analyzed for each fuel type, a small criticality limited design and a 111 kN (25 klbf) thrust class engine design, which has been the focus of numerous manned mission studies, including NASA's Design Reference Architecture 5.0. slightly higher T/W ratios, but they required substantially more 235U.

  1. Presidential Round Table: A Report from the GRAPPA Annual Meeting.

    PubMed

    Gladman, Dafna D; Mease, Philip J; Boehncke, Wolf-Henning; Helliwell, Philip S; Callis Duffin, Kristina

    2016-05-01

    In preparation for strategic planning of the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA), a special session titled the Presidential Round Table took place during the GRAPPA annual meeting in Stockholm, Sweden, in July 2015. During this session, past, current, and incoming presidents of GRAPPA reflected on GRAPPA's history and provided insights about GRAPPA's future, followed by general discussion by the membership. PMID:27134275

  2. Superior mesenteric artery thrombosis after abrupt discontinuation of rivaroxaban.

    PubMed

    Adams, Christopher B; Acquisto, Nicole M; Rotoli, Jason M; LoStracco, Thomas; Shamaskin, Ann R; Pasternack, Joel S

    2016-04-01

    We report a case of superior mesenteric artery thrombosis after the abrupt discontinuation of rivaroxaban in a 59-year-old male patient. The initial presentation was of sudden onset abdominal pain, nausea, vomiting, diarrhea, and hematochezia in the setting of recently holding rivaroxaban anticoagulation for an atrial flutter ablative procedure. Imaging revealed thrombosis of the superior mesenteric artery and acute mesenteric ischemia requiring emergent surgical intervention for embolectomy. Upon exploratory laparotomy, the bowel was found to be viable, and an embolectomy with patch angioplasty was successful without complication. This case illustrates the need for emergency medicine clinician familiarity with this possible medication adverse event with rivaroxaban.

  3. Shock wave interaction with an abrupt area change

    NASA Technical Reports Server (NTRS)

    Salas, Manuel D.

    1991-01-01

    The wave patterns that occur when a shock wave interacts with an abrupt area changed are analyzed in terms of the incident shock wave Mach number and area-jump ratio. The solutions predicted by a semi-similar models are in good agreement with those obtained numerically from the quasi-one-dimensional time-dependent Euler equations. The entropy production for the wave system is defined and the principle of minimum entropy production is used to resolve a nonuniqueness problem of the self-similar model.

  4. Investigations of Abrupt Movements of Optically Trapped Water Droplets

    NASA Astrophysics Data System (ADS)

    Murphy, Shawntel; McCann, Lowell I.

    2007-03-01

    We have used a single beam optical trap (optical tweezers) to capture individual water droplets in air. A 3-dimensional viewing system consisting of a two axis microscope allows the trapped droplet to be viewed from the top and the side simultaneously. The position of the droplet is determined with a digital camera at a rate up to 700Hz. We have observed abrupt movements along the beam in two situations: As a pure water droplet evaporates, the movements occur at specific size intervals as the diameter decreases. For non-evaporating saltwater droplets the movements rapidly occur for certain ranges of beam power, and not at all for other ranges of power.

  5. 7 CFR 1767.13 - Departures from the prescribed RUS Uniform System of Accounts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... (a) No departures are to be made to the prescribed Rural Development USoA without the prior written approval of Rural Development. Requests for departures from the Rural Development USoA shall be addressed... prescribed RUS USoA. (1) If, due to extenuating circumstances, RUS is unable to reach a decision within...

  6. 7 CFR 1767.13 - Departures from the prescribed RUS Uniform System of Accounts.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    .... (a) No departures are to be made to the prescribed Rural Development USoA without the prior written approval of Rural Development. Requests for departures from the Rural Development USoA shall be addressed... prescribed RUS USoA. (1) If, due to extenuating circumstances, RUS is unable to reach a decision within...

  7. 7 CFR 1767.13 - Departures from the prescribed RUS Uniform System of Accounts.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .... (a) No departures are to be made to the prescribed Rural Development USoA without the prior written approval of Rural Development. Requests for departures from the Rural Development USoA shall be addressed... prescribed RUS USoA. (1) If, due to extenuating circumstances, RUS is unable to reach a decision within...

  8. 19 CFR 4.64 - Electronic passenger and crew member departure manifests.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Electronic passenger and crew member departure... SECURITY; DEPARTMENT OF THE TREASURY VESSELS IN FOREIGN AND DOMESTIC TRADES Foreign Clearances § 4.64 Electronic passenger and crew member departure manifests. (a) Definitions. The definitions contained in §...

  9. 8 CFR 236.15 - Voluntary departure and eligibility for employment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the provisions of section 240B of the Act and 8 CFR part 240. (b) Children of legalized aliens... REMOVED Family Unity Program § 236.15 Voluntary departure and eligibility for employment. (a) Authority... to grant voluntary departure under the family unity program derives solely from that...

  10. 8 CFR 236.15 - Voluntary departure and eligibility for employment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the provisions of section 240B of the Act and 8 CFR part 240. (b) Children of legalized aliens... REMOVED Family Unity Program § 236.15 Voluntary departure and eligibility for employment. (a) Authority... to grant voluntary departure under the family unity program derives solely from that...

  11. 8 CFR 236.15 - Voluntary departure and eligibility for employment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the provisions of section 240B of the Act and 8 CFR part 240. (b) Children of legalized aliens... REMOVED Family Unity Program § 236.15 Voluntary departure and eligibility for employment. (a) Authority... to grant voluntary departure under the family unity program derives solely from that...

  12. 8 CFR 236.15 - Voluntary departure and eligibility for employment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the provisions of section 240B of the Act and 8 CFR part 240. (b) Children of legalized aliens... REMOVED Family Unity Program § 236.15 Voluntary departure and eligibility for employment. (a) Authority... to grant voluntary departure under the family unity program derives solely from that...

  13. 8 CFR 236.15 - Voluntary departure and eligibility for employment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the provisions of section 240B of the Act and 8 CFR part 240. (b) Children of legalized aliens... REMOVED Family Unity Program § 236.15 Voluntary departure and eligibility for employment. (a) Authority... to grant voluntary departure under the family unity program derives solely from that...

  14. The Cross-National Relevance of U.S. Formulated Theories of College Student Departure

    ERIC Educational Resources Information Center

    Braxton, John M.

    2013-01-01

    This article focuses on the cross-national relevance of theories of college student departure formulated by U.S. scholars. Some aspects of U.S. developed theories of college student departure hold some semblance of cross-national relevance. Economic and sociological perspectives provide such aspects. The weighing of costs and benefits inherent in…

  15. 8 CFR 240.25 - Voluntary departure-authority of the Service.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Voluntary Departure § 240.25... 240B(a) of the Act to permit aliens to depart voluntarily from the United States may be exercised in... conditions it deems necessary to ensure the alien's timely departure from the United......

  16. 8 CFR 240.25 - Voluntary departure-authority of the Service.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Voluntary Departure § 240.25... 240B(a) of the Act to permit aliens to depart voluntarily from the United States may be exercised in... conditions it deems necessary to ensure the alien's timely departure from the United......

  17. 30 CFR 250.409 - May I obtain departures from these drilling requirements?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations General Requirements § 250.409 May I obtain departures from these drilling requirements? The District Manager may approve departures from the drilling requirements specified in...

  18. 30 CFR 250.409 - May I obtain departures from these drilling requirements?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations General Requirements § 250.409 May I obtain departures from these drilling requirements? The District Manager may approve departures from the drilling requirements specified in...

  19. 30 CFR 250.409 - May I obtain departures from these drilling requirements?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations General Requirements § 250.409 May I obtain departures from these drilling requirements? The District Manager may approve departures from the drilling requirements specified in...

  20. 19 CFR 4.64 - Electronic passenger and crew member departure manifests.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Electronic passenger and crew member departure manifests. 4.64 Section 4.64 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND... Customs and Border Protection (CBP) an electronic passenger departure manifest and an electronic...

  1. Left Unsaid: The Role of Work Expectations and Psychological Contracts in Faculty Careers and Departure

    ERIC Educational Resources Information Center

    O'Meara, KerryAnn; Bennett, Jessica Chalk; Neihaus, Elizabeth

    2016-01-01

    Early career faculty bring many expectations to the door-steps of their new academic homes. Yet such expectations are often left unsaid. Unfortunately, what is left unsaid can be a major factor in faculty departure. This study makes a distinct contribution to the departure literature by examining the psychological contracts and work expectations…

  2. Input-Output Modeling and Control of the Departure Process of Congested Airports

    NASA Technical Reports Server (NTRS)

    Pujet, Nicolas; Delcaire, Bertrand; Feron, Eric

    2003-01-01

    A simple queueing model of busy airport departure operations is proposed. This model is calibrated and validated using available runway configuration and traffic data. The model is then used to evaluate preliminary control schemes aimed at alleviating departure traffic congestion on the airport surface. The potential impact of these control strategies on direct operating costs, environmental costs and overall delay is quantified and discussed.

  3. 77 FR 58915 - Presidential Determination on Major Illicit Drug Transit or Major Illicit Drug Producing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-24

    ... Register. (Presidential Sig.) THE WHITE HOUSE, Washington, September 14, 2012. [FR Doc. 2012-23640 Filed 9..., Dominican Republic, Ecuador, El Salvador, Guatemala, Haiti, Honduras, India, Jamaica, Laos,...

  4. Abrupt climate change and collapse of deep-sea ecosystems

    USGS Publications Warehouse

    Yasuhara, Moriaki; Cronin, T. M.; Demenocal, P.B.; Okahashi, H.; Linsley, B.K.

    2008-01-01

    We investigated the deep-sea fossil record of benthic ostracodes during periods of rapid climate and oceanographic change over the past 20,000 years in a core from intermediate depth in the northwestern Atlantic. Results show that deep-sea benthic community "collapses" occur with faunal turnover of up to 50% during major climatically driven oceanographic changes. Species diversity as measured by the Shannon-Wiener index falls from 3 to as low as 1.6 during these events. Major disruptions in the benthic communities commenced with Heinrich Event 1, the Inter-Aller??d Cold Period (IACP: 13.1 ka), the Younger Dryas (YD: 12.9-11.5 ka), and several Holocene Bond events when changes in deep-water circulation occurred. The largest collapse is associated with the YD/IACP and is characterized by an abrupt two-step decrease in both the upper North Atlantic Deep Water assemblage and species diversity at 13.1 ka and at 12.2 ka. The ostracode fauna at this site did not fully recover until ???8 ka, with the establishment of Labrador Sea Water ventilation. Ecologically opportunistic slope species prospered during this community collapse. Other abrupt community collapses during the past 20 ka generally correspond to millennial climate events. These results indicate that deep-sea ecosystems are not immune to the effects of rapid climate changes occurring over centuries or less. ?? 2008 by The National Academy of Sciences of the USA.

  5. North Pacific deglacial hypoxic events linked to abrupt ocean warming.

    PubMed

    Praetorius, S K; Mix, A C; Walczak, M H; Wolhowe, M D; Addison, J A; Prahl, F G

    2015-11-19

    Marine sediments from the North Pacific document two episodes of expansion and strengthening of the subsurface oxygen minimum zone (OMZ) accompanied by seafloor hypoxia during the last deglacial transition. The mechanisms driving this hypoxia remain under debate. We present a new high-resolution alkenone palaeotemperature reconstruction from the Gulf of Alaska that reveals two abrupt warming events of 4-5 degrees Celsius at the onset of the Bølling and Holocene intervals that coincide with sudden shifts to hypoxia at intermediate depths. The presence of diatomaceous laminations and hypoxia-tolerant benthic foraminiferal species, peaks in redox-sensitive trace metals, and enhanced (15)N/(14)N ratio of organic matter, collectively suggest association with high export production. A decrease in (18)O/(16)O values of benthic foraminifera accompanying the most severe deoxygenation event indicates subsurface warming of up to about 2 degrees Celsius. We infer that abrupt warming triggered expansion of the North Pacific OMZ through reduced oxygen solubility and increased marine productivity via physiological effects; following initiation of hypoxia, remobilization of iron from hypoxic sediments could have provided a positive feedback on ocean deoxygenation through increased nutrient utilization and carbon export. Such a biogeochemical amplification process implies high sensitivity of OMZ expansion to warming.

  6. The abrupt onset of the modern South Asian Monsoon winds.

    PubMed

    Betzler, Christian; Eberli, Gregor P; Kroon, Dick; Wright, James D; Swart, Peter K; Nath, Bejugam Nagender; Alvarez-Zarikian, Carlos A; Alonso-García, Montserrat; Bialik, Or M; Blättler, Clara L; Guo, Junhua Adam; Haffen, Sébastien; Horozal, Senay; Inoue, Mayuri; Jovane, Luigi; Lanci, Luca; Laya, Juan Carlos; Mee, Anna Ling Hui; Lüdmann, Thomas; Nakakuni, Masatoshi; Niino, Kaoru; Petruny, Loren M; Pratiwi, Santi D; Reijmer, John J G; Reolid, Jesús; Slagle, Angela L; Sloss, Craig R; Su, Xiang; Yao, Zhengquan; Young, Jeremy R

    2016-07-20

    The South Asian Monson (SAM) is one of the most intense climatic elements yet its initiation and variations are not well established. Dating the deposits of SAM wind-driven currents in IODP cores from the Maldives yields an age of 12. 9 Ma indicating an abrupt SAM onset, over a short period of 300 kyrs. This coincided with the Indian Ocean Oxygen Minimum Zone expansion as revealed by geochemical tracers and the onset of upwelling reflected by the sediment's content of particulate organic matter. A weaker 'proto-monsoon' existed between 12.9 and 25 Ma, as mirrored by the sedimentary signature of dust influx. Abrupt SAM initiation favors a strong influence of climate in addition to the tectonic control, and we propose that the post Miocene Climate Optimum cooling, together with increased continentalization and establishment of the bipolar ocean circulation, i.e. the beginning of the modern world, shifted the monsoon over a threshold towards the modern system.

  7. The abrupt onset of the modern South Asian Monsoon winds

    NASA Astrophysics Data System (ADS)

    Betzler, Christian; Eberli, Gregor P.; Kroon, Dick; Wright, James D.; Swart, Peter K.; Nath, Bejugam Nagender; Alvarez-Zarikian, Carlos A.; Alonso-García, Montserrat; Bialik, Or M.; Blättler, Clara L.; Guo, Junhua Adam; Haffen, Sébastien; Horozal, Senay; Inoue, Mayuri; Jovane, Luigi; Lanci, Luca; Laya, Juan Carlos; Mee, Anna Ling Hui; Lüdmann, Thomas; Nakakuni, Masatoshi; Niino, Kaoru; Petruny, Loren M.; Pratiwi, Santi D.; Reijmer, John J. G.; Reolid, Jesús; Slagle, Angela L.; Sloss, Craig R.; Su, Xiang; Yao, Zhengquan; Young, Jeremy R.

    2016-07-01

    The South Asian Monson (SAM) is one of the most intense climatic elements yet its initiation and variations are not well established. Dating the deposits of SAM wind-driven currents in IODP cores from the Maldives yields an age of 12. 9 Ma indicating an abrupt SAM onset, over a short period of 300 kyrs. This coincided with the Indian Ocean Oxygen Minimum Zone expansion as revealed by geochemical tracers and the onset of upwelling reflected by the sediment’s content of particulate organic matter. A weaker ‘proto-monsoon’ existed between 12.9 and 25 Ma, as mirrored by the sedimentary signature of dust influx. Abrupt SAM initiation favors a strong influence of climate in addition to the tectonic control, and we propose that the post Miocene Climate Optimum cooling, together with increased continentalization and establishment of the bipolar ocean circulation, i.e. the beginning of the modern world, shifted the monsoon over a threshold towards the modern system.

  8. The abrupt onset of the modern South Asian Monsoon winds

    PubMed Central

    Betzler, Christian; Eberli, Gregor P.; Kroon, Dick; Wright, James D.; Swart, Peter K.; Nath, Bejugam Nagender; Alvarez-Zarikian, Carlos A.; Alonso-García, Montserrat; Bialik, Or M.; Blättler, Clara L.; Guo, Junhua Adam; Haffen, Sébastien; Horozal, Senay; Inoue, Mayuri; Jovane, Luigi; Lanci, Luca; Laya, Juan Carlos; Mee, Anna Ling Hui; Lüdmann, Thomas; Nakakuni, Masatoshi; Niino, Kaoru; Petruny, Loren M.; Pratiwi, Santi D.; Reijmer, John J. G.; Reolid, Jesús; Slagle, Angela L.; Sloss, Craig R.; Su, Xiang; Yao, Zhengquan; Young, Jeremy R.

    2016-01-01

    The South Asian Monson (SAM) is one of the most intense climatic elements yet its initiation and variations are not well established. Dating the deposits of SAM wind-driven currents in IODP cores from the Maldives yields an age of 12. 9 Ma indicating an abrupt SAM onset, over a short period of 300 kyrs. This coincided with the Indian Ocean Oxygen Minimum Zone expansion as revealed by geochemical tracers and the onset of upwelling reflected by the sediment’s content of particulate organic matter. A weaker ‘proto-monsoon’ existed between 12.9 and 25 Ma, as mirrored by the sedimentary signature of dust influx. Abrupt SAM initiation favors a strong influence of climate in addition to the tectonic control, and we propose that the post Miocene Climate Optimum cooling, together with increased continentalization and establishment of the bipolar ocean circulation, i.e. the beginning of the modern world, shifted the monsoon over a threshold towards the modern system. PMID:27436574

  9. The abrupt onset of the modern South Asian Monsoon winds.

    PubMed

    Betzler, Christian; Eberli, Gregor P; Kroon, Dick; Wright, James D; Swart, Peter K; Nath, Bejugam Nagender; Alvarez-Zarikian, Carlos A; Alonso-García, Montserrat; Bialik, Or M; Blättler, Clara L; Guo, Junhua Adam; Haffen, Sébastien; Horozal, Senay; Inoue, Mayuri; Jovane, Luigi; Lanci, Luca; Laya, Juan Carlos; Mee, Anna Ling Hui; Lüdmann, Thomas; Nakakuni, Masatoshi; Niino, Kaoru; Petruny, Loren M; Pratiwi, Santi D; Reijmer, John J G; Reolid, Jesús; Slagle, Angela L; Sloss, Craig R; Su, Xiang; Yao, Zhengquan; Young, Jeremy R

    2016-01-01

    The South Asian Monson (SAM) is one of the most intense climatic elements yet its initiation and variations are not well established. Dating the deposits of SAM wind-driven currents in IODP cores from the Maldives yields an age of 12. 9 Ma indicating an abrupt SAM onset, over a short period of 300 kyrs. This coincided with the Indian Ocean Oxygen Minimum Zone expansion as revealed by geochemical tracers and the onset of upwelling reflected by the sediment's content of particulate organic matter. A weaker 'proto-monsoon' existed between 12.9 and 25 Ma, as mirrored by the sedimentary signature of dust influx. Abrupt SAM initiation favors a strong influence of climate in addition to the tectonic control, and we propose that the post Miocene Climate Optimum cooling, together with increased continentalization and establishment of the bipolar ocean circulation, i.e. the beginning of the modern world, shifted the monsoon over a threshold towards the modern system. PMID:27436574

  10. Abrupt formation of isolated superconducting droplets in heavily disordered cuprates

    NASA Astrophysics Data System (ADS)

    Naqib, S. H.; Islam, R. S.

    2011-10-01

    The effect of controlled disorder on the superconducting transition temperature, Tc, resistivity, and the magnitude of the field-cooled ac susceptibility (ACS) has been investigated for Ca and Zn substituted Y123 (Y0.80Ca0.20Ba2(Cu1 - yZny)3O7 - δ) sintered compounds over a wide range of compositions. Ca was used to explore the overdoped side. The in-plane hole content, p, was changed by varying the oxygen deficiency (δ). Irrespective of the hole content, Tc decreased almost linearly with Zn, though the rate of suppression was strongly p dependent. The magnitude of the low-field, field-cooled ACS, on the other hand, decreased abruptly and significantly for the heavily disordered (y > 0.05) sintered compounds when p was decreased. More strikingly, the qualitative features of the field dependent ACS signal became identical for sintered and powdered samples, indicating a complete absence of coupling among superconducting grains in heavily disordered Y0.80Ca0.20Ba2(Cu1 - yZny)3O7 - δ. A non-monotonic and pronounced enhancement of the residual resistivity for samples with y > 0.05 lends further support to this picture. The abruptness of this 'isolated superconducting droplet' behavior points toward possible interplay among various length scales. We discuss the implications of these findings in detail in this paper.

  11. North Pacific deglacial hypoxic events linked to abrupt ocean warming.

    PubMed

    Praetorius, S K; Mix, A C; Walczak, M H; Wolhowe, M D; Addison, J A; Prahl, F G

    2015-11-19

    Marine sediments from the North Pacific document two episodes of expansion and strengthening of the subsurface oxygen minimum zone (OMZ) accompanied by seafloor hypoxia during the last deglacial transition. The mechanisms driving this hypoxia remain under debate. We present a new high-resolution alkenone palaeotemperature reconstruction from the Gulf of Alaska that reveals two abrupt warming events of 4-5 degrees Celsius at the onset of the Bølling and Holocene intervals that coincide with sudden shifts to hypoxia at intermediate depths. The presence of diatomaceous laminations and hypoxia-tolerant benthic foraminiferal species, peaks in redox-sensitive trace metals, and enhanced (15)N/(14)N ratio of organic matter, collectively suggest association with high export production. A decrease in (18)O/(16)O values of benthic foraminifera accompanying the most severe deoxygenation event indicates subsurface warming of up to about 2 degrees Celsius. We infer that abrupt warming triggered expansion of the North Pacific OMZ through reduced oxygen solubility and increased marine productivity via physiological effects; following initiation of hypoxia, remobilization of iron from hypoxic sediments could have provided a positive feedback on ocean deoxygenation through increased nutrient utilization and carbon export. Such a biogeochemical amplification process implies high sensitivity of OMZ expansion to warming. PMID:26581293

  12. Early warnings and missed alarms for abrupt monsoon transitions

    NASA Astrophysics Data System (ADS)

    Thomas, Z. A.; Kwasniok, F.; Boulton, C. A.; Cox, P. M.; Jones, R. T.; Lenton, T. M.; Turney, C. S. M.

    2015-04-01

    Palaeo-records from China (Cheng et al., 2009; Wang et al., 2008, 2001) demonstrate the East Asian Summer Monsoon (EASM) is dominated by abrupt and large magnitude monsoon shifts on millennial timescales, switching between periods of high and weak monsoon rains. It has been hypothesised that over these timescales, the EASM exhibits two stable states with bifurcation-type tipping points between them (Schewe et al., 2012). Here we test this hypothesis by looking for early warning signals of past bifurcations in speleothem records from Sanbao Cave and Hulu Cave, China (Wang et al., 2008, 2001), spanning the penultimate glacial cycle, and in multiple model simulations derived from the data. We find hysteresis behaviour in our model simulations with transitions directly forced by solar insolation. We detect critical slowing down prior to an abrupt monsoon shift during the penultimate deglaciation consistent with long-term orbital forcing. However, such signals are only detectable when the change in system stability is sufficiently slow to be detected by the sampling resolution of the dataset, raising the possibility that the alarm was missed and a similar forcing drove earlier EASM shifts.

  13. Early warnings and missed alarms for abrupt monsoon transitions

    NASA Astrophysics Data System (ADS)

    Thomas, Z. A.; Kwasniok, F.; Boulton, C. A.; Cox, P. M.; Jones, R. T.; Lenton, T. M.; Turney, C. S. M.

    2015-12-01

    Palaeo-records from China demonstrate that the East Asian Summer Monsoon (EASM) is dominated by abrupt and large magnitude monsoon shifts on millennial timescales, switching between periods of high and weak monsoon rains. It has been hypothesized that over these timescales, the EASM exhibits two stable states with bifurcation-type tipping points between them. Here we test this hypothesis by looking for early warning signals of past bifurcations in speleothem δ18O records from Sanbao Cave and Hulu Cave, China, spanning the penultimate glacial cycle. We find that although there are increases in both autocorrelation and variance preceding some of the monsoon transitions during this period, it is only immediately prior to the abrupt monsoon shift at the penultimate deglaciation (Termination II) that statistically significant increases are detected. To supplement our data analysis, we produce and analyse multiple model simulations that we derive from these data. We find hysteresis behaviour in our model simulations with transitions directly forced by solar insolation. However, signals of critical slowing down, which occur on the approach to a bifurcation, are only detectable in the model simulations when the change in system stability is sufficiently slow to be detected by the sampling resolution of the data set. This raises the possibility that the early warning "alarms" were missed in the speleothem data over the period 224-150 kyr and it was only at the monsoon termination that the change in the system stability was sufficiently slow to detect early warning signals.

  14. Use of very low departure aspheric surfaces in high quality camera lenses

    NASA Astrophysics Data System (ADS)

    Dalzell, Kristen E.; Jonas, Reginald P.; Thorpe, Michael D.

    2014-12-01

    High performance, compact cinematography lenses working over a large sensor area are demanding designs which are achieved using one or two high departure aspheric elements. With sag departures from best fit sphere of up to a few millimeters, the use of such aspheres is accompanied by a number of consequences. These include high cost metrology, very tight opto-mechanical tolerances and the potential for image artifacts produced during the sub-aperture grinding and polishing process. A modified asphere manufacturing process was utilized to reduce artifacts by eliminating the subaperture grinding and pre-polishing. This method is limited to aspheric surfaces which can be directly polished from a spherical base surface with aspheric departures of <15μm. These very low departure aspheres have the benefit of inexpensive metrology and tolerance relaxation compared with high departure aspheres. Interferograms, slope maps, and out-of-focus images demonstrate the feasibility and advantages of direct asphere generation from a polished sphere. A series of large format lenses covering focal lengths from telephoto to wide angle, were redesigned to determine the feasibility of the use of very low departure aspheres. Increasing the number of aspheric surfaces but reducing the aspheric departure to less than 15μm was demonstrated. We conclude that 3-5 very low departure aspheres are sufficient to provide similar performance to the high departure asphere designs for most focal lengths. One limitation encountered was in the wide angle lenses. The exception was the wide angle lenses where it is difficult to reduce departures below 30μm while maintaining the same optical performance.

  15. Integrated Arrival and Departure Schedule Optimization Under Uncertainty

    NASA Technical Reports Server (NTRS)

    Xue, Min; Zelinski, Shannon

    2014-01-01

    In terminal airspace, integrating arrivals and departures with shared waypoints provides the potential of improving operational efficiency by allowing direct routes when possible. Incorporating stochastic evaluation as a post-analysis process of deterministic optimization, and imposing a safety buffer in deterministic optimization, are two ways to learn and alleviate the impact of uncertainty and to avoid unexpected outcomes. This work presents a third and direct way to take uncertainty into consideration during the optimization. The impact of uncertainty was incorporated into cost evaluations when searching for the optimal solutions. The controller intervention count was computed using a heuristic model and served as another stochastic cost besides total delay. Costs under uncertainty were evaluated using Monte Carlo simulations. The Pareto fronts that contain a set of solutions were identified and the trade-off between delays and controller intervention count was shown. Solutions that shared similar delays but had different intervention counts were investigated. The results showed that optimization under uncertainty could identify compromise solutions on Pareto fonts, which is better than deterministic optimization with extra safety buffers. It helps decision-makers reduce controller intervention while achieving low delays.

  16. Human Factors Considerations for Area Navigation Departure and Arrival Procedures

    NASA Technical Reports Server (NTRS)

    Barhydt, Richard; Adams, Catherine A.

    2006-01-01

    Area navigation (RNAV) procedures are being implemented in the United States and around the world as part of a transition to a performance-based navigation system. These procedures are providing significant benefits and have also caused some human factors issues to emerge. Under sponsorship from the Federal Aviation Administration (FAA), the National Aeronautics and Space Administration (NASA) has undertaken a project to document RNAV-related human factors issues and propose areas for further consideration. The component focusing on RNAV Departure and Arrival Procedures involved discussions with expert users, a literature review, and a focused review of the NASA Aviation Safety Reporting System (ASRS) database. Issues were found to include aspects of air traffic control and airline procedures, aircraft systems, and procedure design. Major findings suggest the need for specific instrument procedure design guidelines that consider the effects of human performance. Ongoing industry and government activities to address air-ground communication terminology, design improvements, and chart-database commonality are strongly encouraged. A review of factors contributing to RNAV in-service errors would likely lead to improved system design and operational performance.

  17. Abrupt climate shift in the Western Mediterranean Sea

    PubMed Central

    Schroeder, K.; Chiggiato, J.; Bryden, H. L.; Borghini, M.; Ben Ismail, S.

    2016-01-01

    One century of oceanographic measurements has evidenced gradual increases in temperature and salinity of western Mediterranean water masses, even though the vertical stratification has basically remained unchanged. Starting in 2005, the basic structure of the intermediate and deep layers abruptly changed. We report here evidence of reinforced thermohaline variability in the deep western basin with significant dense water formation events producing large amounts of warmer, saltier and denser water masses than ever before. We provide a detailed chronological order to these changes, giving an overview of the new water masses and following their route from the central basin interior to the east (toward the Tyrrhenian) and toward the Atlantic Ocean. As a consequence of this climate shift, new deep waters outflowing through Gibraltar will impact the North Atlantic in terms of salt and heat input. In addition, modifications in the Mediterranean abyssal ecosystems and biogeochemical cycles are to be expected. PMID:26965790

  18. Abrupt rise of new machine ecology beyond human response time

    PubMed Central

    Johnson, Neil; Zhao, Guannan; Hunsader, Eric; Qi, Hong; Johnson, Nicholas; Meng, Jing; Tivnan, Brian

    2013-01-01

    Society's techno-social systems are becoming ever faster and more computer-orientated. However, far from simply generating faster versions of existing behaviour, we show that this speed-up can generate a new behavioural regime as humans lose the ability to intervene in real time. Analyzing millisecond-scale data for the world's largest and most powerful techno-social system, the global financial market, we uncover an abrupt transition to a new all-machine phase characterized by large numbers of subsecond extreme events. The proliferation of these subsecond events shows an intriguing correlation with the onset of the system-wide financial collapse in 2008. Our findings are consistent with an emerging ecology of competitive machines featuring ‘crowds' of predatory algorithms, and highlight the need for a new scientific theory of subsecond financial phenomena. PMID:24022120

  19. Abrupt Change 8200 Years Ago: The Smoking Gun?

    NASA Astrophysics Data System (ADS)

    Alley, R. B.

    2003-12-01

    The large, rapid, widespread climate change about 8200 years ago followed a large freshening of the North Atlantic Ocean, and produced climate anomalies in the Northern Hemisphere that are consistent with the expected response to North Atlantic cooling and that mimic the larger and longer-lasting effects of the Younger Dryas and older events. The short-lived nature of this Holocene event explains the lack of a signal at high southern latitudes, and the other features support the hypotheses that abrupt climate changes have been forced by North Atlantic freshening, and that Holocene warmth is not a guarantee of stability. Comparison of modeled and observed impacts of North Atlantic freshening suggests that some models are somewhat undersensitive compared to the real world.

  20. Abrupt tectonics and rapid slab detachment with grain damage.

    PubMed

    Bercovici, David; Schubert, Gerald; Ricard, Yanick

    2015-02-01

    A simple model for necking and detachment of subducting slabs is developed to include the coupling between grain-sensitive rheology and grain-size evolution with damage. Necking is triggered by thickened buoyant crust entrained into a subduction zone, in which case grain damage accelerates necking and allows for relatively rapid slab detachment, i.e., within 1 My, depending on the size of the crustal plug. Thick continental crustal plugs can cause rapid necking while smaller plugs characteristic of ocean plateaux cause slower necking; oceanic lithosphere with normal or slightly thickened crust subducts without necking. The model potentially explains how large plateaux or continental crust drawn into subduction zones can cause slab loss and rapid changes in plate motion and/or induce abrupt continental rebound. PMID:25605890

  1. Thunderstorm Ground Enhancements Abruptly Terminated by the Lightning Flash

    NASA Astrophysics Data System (ADS)

    Chilingarian, A. A.; Sogomonyan, S. B.

    2015-12-01

    Electrons giving rise to the Thunderstorm ground enhancements (TGEs) are accelerated in the lower dipole formed by the main negatively charged region in the middle of the cloud and the transient lower positively charged region (LPCR). The LPCR prevents the lightning leader from reaching the ground and usually no -CG lightning occurs during mature LPCR when the particle flux is sizable. Only after decaying of the LPCR lightning the stepped leader makes its path to the ground. Polarized water droplets also have a role in the TGE initiation. Our observations show that only at high humidity the TGEs at Aragats are possible and rains terminate the particle fluxes. We consider TGE events abruptly terminated by the lightning discharge. Proceeding from the large collection of the sharply stopped TGE events detected on Mt. Aragats we investigated how particle fluxes can help the stepped leader to reach the ground.

  2. Abrupt tectonics and rapid slab detachment with grain damage.

    PubMed

    Bercovici, David; Schubert, Gerald; Ricard, Yanick

    2015-02-01

    A simple model for necking and detachment of subducting slabs is developed to include the coupling between grain-sensitive rheology and grain-size evolution with damage. Necking is triggered by thickened buoyant crust entrained into a subduction zone, in which case grain damage accelerates necking and allows for relatively rapid slab detachment, i.e., within 1 My, depending on the size of the crustal plug. Thick continental crustal plugs can cause rapid necking while smaller plugs characteristic of ocean plateaux cause slower necking; oceanic lithosphere with normal or slightly thickened crust subducts without necking. The model potentially explains how large plateaux or continental crust drawn into subduction zones can cause slab loss and rapid changes in plate motion and/or induce abrupt continental rebound.

  3. Abrupt climate shift in the Western Mediterranean Sea.

    PubMed

    Schroeder, K; Chiggiato, J; Bryden, H L; Borghini, M; Ben Ismail, S

    2016-01-01

    One century of oceanographic measurements has evidenced gradual increases in temperature and salinity of western Mediterranean water masses, even though the vertical stratification has basically remained unchanged. Starting in 2005, the basic structure of the intermediate and deep layers abruptly changed. We report here evidence of reinforced thermohaline variability in the deep western basin with significant dense water formation events producing large amounts of warmer, saltier and denser water masses than ever before. We provide a detailed chronological order to these changes, giving an overview of the new water masses and following their route from the central basin interior to the east (toward the Tyrrhenian) and toward the Atlantic Ocean. As a consequence of this climate shift, new deep waters outflowing through Gibraltar will impact the North Atlantic in terms of salt and heat input. In addition, modifications in the Mediterranean abyssal ecosystems and biogeochemical cycles are to be expected. PMID:26965790

  4. Abrupt climate shift in the Western Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Schroeder, K.; Chiggiato, J.; Bryden, H. L.; Borghini, M.; Ben Ismail, S.

    2016-03-01

    One century of oceanographic measurements has evidenced gradual increases in temperature and salinity of western Mediterranean water masses, even though the vertical stratification has basically remained unchanged. Starting in 2005, the basic structure of the intermediate and deep layers abruptly changed. We report here evidence of reinforced thermohaline variability in the deep western basin with significant dense water formation events producing large amounts of warmer, saltier and denser water masses than ever before. We provide a detailed chronological order to these changes, giving an overview of the new water masses and following their route from the central basin interior to the east (toward the Tyrrhenian) and toward the Atlantic Ocean. As a consequence of this climate shift, new deep waters outflowing through Gibraltar will impact the North Atlantic in terms of salt and heat input. In addition, modifications in the Mediterranean abyssal ecosystems and biogeochemical cycles are to be expected.

  5. Abrupt tectonics and rapid slab detachment with grain damage

    PubMed Central

    Bercovici, David; Schubert, Gerald; Ricard, Yanick

    2015-01-01

    A simple model for necking and detachment of subducting slabs is developed to include the coupling between grain-sensitive rheology and grain-size evolution with damage. Necking is triggered by thickened buoyant crust entrained into a subduction zone, in which case grain damage accelerates necking and allows for relatively rapid slab detachment, i.e., within 1 My, depending on the size of the crustal plug. Thick continental crustal plugs can cause rapid necking while smaller plugs characteristic of ocean plateaux cause slower necking; oceanic lithosphere with normal or slightly thickened crust subducts without necking. The model potentially explains how large plateaux or continental crust drawn into subduction zones can cause slab loss and rapid changes in plate motion and/or induce abrupt continental rebound. PMID:25605890

  6. Abrupt glacial climate shifts controlled by ice sheet changes.

    PubMed

    Zhang, Xu; Lohmann, Gerrit; Knorr, Gregor; Purcell, Conor

    2014-08-21

    During glacial periods of the Late Pleistocene, an abundance of proxy data demonstrates the existence of large and repeated millennial-scale warming episodes, known as Dansgaard-Oeschger (DO) events. This ubiquitous feature of rapid glacial climate change can be extended back as far as 800,000 years before present (BP) in the ice core record, and has drawn broad attention within the science and policy-making communities alike. Many studies have been dedicated to investigating the underlying causes of these changes, but no coherent mechanism has yet been identified. Here we show, by using a comprehensive fully coupled model, that gradual changes in the height of the Northern Hemisphere ice sheets (NHISs) can alter the coupled atmosphere-ocean system and cause rapid glacial climate shifts closely resembling DO events. The simulated global climate responses--including abrupt warming in the North Atlantic, a northward shift of the tropical rainbelts, and Southern Hemisphere cooling related to the bipolar seesaw--are generally consistent with empirical evidence. As a result of the coexistence of two glacial ocean circulation states at intermediate heights of the ice sheets, minor changes in the height of the NHISs and the amount of atmospheric CO2 can trigger the rapid climate transitions via a local positive atmosphere-ocean-sea-ice feedback in the North Atlantic. Our results, although based on a single model, thus provide a coherent concept for understanding the recorded millennial-scale variability and abrupt climate changes in the coupled atmosphere-ocean system, as well as their linkages to the volume of the intermediate ice sheets during glacials.

  7. Low-latitude mountain glacier evidence for abrupt climate changes

    NASA Astrophysics Data System (ADS)

    Thompson, L. G.; Mosley-Thompson, E. S.; Lin, P.; Davis, M. E.; Mashiotta, T. A.; Brecher, H. H.

    2004-12-01

    Clear evidence that a widespread warming of Earth's climate system is now underway comes from low latitude mountain glaciers. Proxy temperature histories reconstructed from ice cores, and the rapidly accelerating loss of both the total ice area and ice volume on a near global scale suggest that these glaciers responding to increasing rates of melting. In situ observations reveal the startling rates at which many tropical glaciers are disappearing. For example, the retreat of the terminus of the Qori Kalis Glacier in Peru is roughly 200 meters per year, 40 times faster than its retreat rate in 1978. Similarly, in 1912 the ice on Mount Kilimanjaro covered 12.1 km2, but today it covers only 2.6 km2. If the current rate of retreat continues, the perennial ice fields may disappear within the next few decades, making this the first time in the past 11,700 years that Kilimanjaro will be devoid of the ice that shrouds its summit. Tropical glaciers may be considered ``the canaries in the coal mine'' for the global climate system as they integrate and respond to key climatological variables, such as temperature, precipitation, cloudiness, humidity, and incident solar radiation. A composite of the decadally-averaged oxygen isotopic records from three Andean and three Tibetan ice cores extending back over the last two millennia shows an isotopic enrichment in the 20th century that suggests a large-scale warming is underway at lower latitudes. Multiple lines of evidence from Africa, the Middle East, Europe and South America indicate an abrupt mid-Holocene climate event in the low latitudes. If such an event were to occur now with a global human population of 6.3 billion people, the consequences could be severe. Clearly, we need to understand the nature and cause of abrupt climate events.

  8. Abrupt glacial climate shifts controlled by ice sheet changes

    NASA Astrophysics Data System (ADS)

    Zhang, Xu; Lohmann, Gerrit; Knorr, Gregor; Purcell, Conor

    2014-08-01

    During glacial periods of the Late Pleistocene, an abundance of proxy data demonstrates the existence of large and repeated millennial-scale warming episodes, known as Dansgaard-Oeschger (DO) events. This ubiquitous feature of rapid glacial climate change can be extended back as far as 800,000 years before present (BP) in the ice core record, and has drawn broad attention within the science and policy-making communities alike. Many studies have been dedicated to investigating the underlying causes of these changes, but no coherent mechanism has yet been identified. Here we show, by using a comprehensive fully coupled model, that gradual changes in the height of the Northern Hemisphere ice sheets (NHISs) can alter the coupled atmosphere-ocean system and cause rapid glacial climate shifts closely resembling DO events. The simulated global climate responses--including abrupt warming in the North Atlantic, a northward shift of the tropical rainbelts, and Southern Hemisphere cooling related to the bipolar seesaw--are generally consistent with empirical evidence. As a result of the coexistence of two glacial ocean circulation states at intermediate heights of the ice sheets, minor changes in the height of the NHISs and the amount of atmospheric CO2 can trigger the rapid climate transitions via a local positive atmosphere-ocean-sea-ice feedback in the North Atlantic. Our results, although based on a single model, thus provide a coherent concept for understanding the recorded millennial-scale variability and abrupt climate changes in the coupled atmosphere-ocean system, as well as their linkages to the volume of the intermediate ice sheets during glacials.

  9. Abrupt glacial climate shifts controlled by ice sheet changes.

    PubMed

    Zhang, Xu; Lohmann, Gerrit; Knorr, Gregor; Purcell, Conor

    2014-08-21

    During glacial periods of the Late Pleistocene, an abundance of proxy data demonstrates the existence of large and repeated millennial-scale warming episodes, known as Dansgaard-Oeschger (DO) events. This ubiquitous feature of rapid glacial climate change can be extended back as far as 800,000 years before present (BP) in the ice core record, and has drawn broad attention within the science and policy-making communities alike. Many studies have been dedicated to investigating the underlying causes of these changes, but no coherent mechanism has yet been identified. Here we show, by using a comprehensive fully coupled model, that gradual changes in the height of the Northern Hemisphere ice sheets (NHISs) can alter the coupled atmosphere-ocean system and cause rapid glacial climate shifts closely resembling DO events. The simulated global climate responses--including abrupt warming in the North Atlantic, a northward shift of the tropical rainbelts, and Southern Hemisphere cooling related to the bipolar seesaw--are generally consistent with empirical evidence. As a result of the coexistence of two glacial ocean circulation states at intermediate heights of the ice sheets, minor changes in the height of the NHISs and the amount of atmospheric CO2 can trigger the rapid climate transitions via a local positive atmosphere-ocean-sea-ice feedback in the North Atlantic. Our results, although based on a single model, thus provide a coherent concept for understanding the recorded millennial-scale variability and abrupt climate changes in the coupled atmosphere-ocean system, as well as their linkages to the volume of the intermediate ice sheets during glacials. PMID:25119027

  10. Internal or External: Community College Presidential Backgrounds and Management of the Presidency

    ERIC Educational Resources Information Center

    Strickland, Shelley Renae

    2013-01-01

    Some in the education community have hypothesized that presidential candidates with external backgrounds, such as fundraising or development, have become more viable candidates for the presidency because of more externally-focused core competencies and expectations of the community college presidential role. This study investigated whether…

  11. Revealing Character and Addressing Voters' Needs in the 1992 Presidential Debates: A Content Analysis.

    ERIC Educational Resources Information Center

    Leon, Mary-Ann

    1993-01-01

    Considers the linguistic choices of candidates in the 1992 presidential election debates as intending to display presidential character and as suggestive of an ability to satisfy voters' needs. Analyzes the three candidates' dimensions of perceived character and ability to address needs. (HB)

  12. Teachers' Controversial Issue Decisions Related to Race, Gender, and Religion during the 2008 Presidential Election

    ERIC Educational Resources Information Center

    Journell, Wayne

    2011-01-01

    Using the 2008 Presidential Election as a case of curricular controversy, the author describes how six high school government teachers responded to the racial, gender, and religious diversity included on the presidential tickets of the two major political parties. Teachers had to decide whether the issue of Americans challenging the tradition of…

  13. 36 CFR 1280.92 - When are the Presidential library museums open to the public?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... are also posted at http://www.archives.gov. (b) See 36 CFR 1253.3 for the operating hours of the... library museums open to the public? 1280.92 Section 1280.92 Parks, Forests, and Public Property NATIONAL... Use of Facilities in Presidential Libraries? § 1280.92 When are the Presidential library museums...

  14. 36 CFR 1280.92 - When are the Presidential library museums open to the public?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... are also posted at http://www.archives.gov. (b) See 36 CFR 1253.3 for the operating hours of the... library museums open to the public? 1280.92 Section 1280.92 Parks, Forests, and Public Property NATIONAL... Use of Facilities in Presidential Libraries? § 1280.92 When are the Presidential library museums...

  15. 78 FR 49516 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-14

    ... of HIV disease and AIDS. The functions of the Council are solely advisory in nature. The Council... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Office of the Assistant... Service (DHHS) is hereby giving notice that the Presidential Advisory Council on HIV/AIDS (PACHA)...

  16. 77 FR 40884 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-11

    ... regarding programs and policies intended to promote effective prevention of HIV disease and AIDS. The... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Department of Health and... Service (DHHS) is hereby giving notice that the Presidential Advisory Council ] on HIV/AIDS (PACHA)...

  17. 76 FR 27323 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-11

    ... regarding programs and policies to promote effective prevention of HIV disease and AIDS. The functions of... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Office of the Assistant... Service (DHHS) is hereby giving notice that the Presidential Advisory Council on HIV/AIDS (PACHA)...

  18. 77 FR 59196 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-26

    ... programs and policies intended to promote effective prevention of HIV disease and AIDS. The functions of... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Department of Health and... Service (DHHS) is hereby giving notice that the Presidential Advisory Council on HIV/AIDS (PACHA)...

  19. 76 FR 1167 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-07

    ... Secretary regarding programs and policies to promote effective prevention and cure of HIV disease and AIDS... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Department of Health and... Service (DHHS) is hereby giving notice that the Presidential Advisory Council on HIV/AIDS (PACHA)...

  20. 77 FR 74016 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-12

    ... programs and policies intended to promote effective prevention of HIV disease and AIDS. The functions of... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Office of the Assistant... Service (DHHS) is hereby giving notice that the Presidential Advisory Council on HIV/AIDS (PACHA)...

  1. 77 FR 25482 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-30

    ... programs and policies intended to promote effective prevention of HIV disease and AIDS. The functions of... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Department of Health and... Service (DHHS) is hereby giving notice that the Presidential Advisory Council on HIV/AIDS (PACHA)...

  2. 36 CFR 1256.10 - How do I obtain access to Nixon Presidential materials?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false How do I obtain access to Nixon Presidential materials? 1256.10 Section 1256.10 Parks, Forests, and Public Property NATIONAL... MATERIALS General Information § 1256.10 How do I obtain access to Nixon Presidential materials? See 36...

  3. Selecting Presidential Nominees: The Evolution of the Current System and Prospects for Reform.

    ERIC Educational Resources Information Center

    Piroth, Scott

    2000-01-01

    Discusses how political parties select presidential candidates focusing on the roles of party leaders, activities, supporters, and campaign contributors. Discusses the history of presidential nominations focusing on how the present system evolved. Reviews a particular reform proposal called the Delaware Plan that intends to stop the front loading…

  4. 75 FR 57024 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-17

    ... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Department of Health and... Services (DHHS) is hereby giving notice that the Presidential Advisory Council on HIV/AIDS (PACHA) will... on HIV/AIDS, Department of Health and Human Services, 200 Independence Avenue, SW., Room...

  5. 78 FR 46671 - Membership on the Presidential Task Force on Wildlife Trafficking

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Membership on the Presidential Task Force on Wildlife Trafficking By virtue of the authority vested in me as... of State representative to the Presidential Task Force on Wildlife Trafficking, established...

  6. Newspaper Photographs and the 1996 Presidential Election: The Question of Bias.

    ERIC Educational Resources Information Center

    Waldman, Paul; Devitt, James

    1998-01-01

    Contributes to research regarding the impact of news media on presidential elections. Performs a content analysis of photographs of Bill Clinton and Bob Dole in five major newspapers. Rejects the conclusions of "liberal bias" in the press coverage of presidential campaigns, arguing instead for the presence of a strategic bias benefitting the…

  7. Student Engagement and Teacher Practices: Using Hillary Clinton's Presidential Campaign for Learning Purposes

    ERIC Educational Resources Information Center

    Gruber, Sibylle

    2011-01-01

    In this article, I reflect on the pedagogical decisions I made when I taught a course on gendered literacies during the 2008/2009 presidential campaign. I specifically focus on what I term the "Hillary" phenomenon, the media's often negative and unflattering portrayal of presidential candidate Hillary Clinton. I start with a brief…

  8. 36 CFR 1275.46 - Segregation and review; Senior Archival Panel; Presidential Materials Review Board.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Segregation and review; Senior Archival Panel; Presidential Materials Review Board. 1275.46 Section 1275.46 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NIXON PRESIDENTIAL MATERIALS...

  9. 36 CFR 1275.46 - Segregation and review; Senior Archival Panel; Presidential Materials Review Board.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Segregation and review; Senior Archival Panel; Presidential Materials Review Board. 1275.46 Section 1275.46 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NIXON PRESIDENTIAL MATERIALS...

  10. 36 CFR 1275.46 - Segregation and review; Senior Archival Panel; Presidential Materials Review Board.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Segregation and review; Senior Archival Panel; Presidential Materials Review Board. 1275.46 Section 1275.46 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NIXON PRESIDENTIAL MATERIALS PRESERVATION...

  11. 36 CFR 1275.46 - Segregation and review; Senior Archival Panel; Presidential Materials Review Board.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Segregation and review; Senior Archival Panel; Presidential Materials Review Board. 1275.46 Section 1275.46 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NIXON PRESIDENTIAL MATERIALS...

  12. 36 CFR 1275.46 - Segregation and review; Senior Archival Panel; Presidential Materials Review Board.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Segregation and review; Senior Archival Panel; Presidential Materials Review Board. 1275.46 Section 1275.46 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION NIXON PRESIDENTIAL MATERIALS...

  13. 3 CFR 13489 - Executive Order 13489 of January 21, 2009. Presidential Records

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and the laws of the United States of America, and in order to establish policies and procedures... documentary materials maintained by NARA pursuant to the Presidential Records Act, including Vice Presidential... (ii) functions of the Director of the Office of Management and Budget relating to...

  14. 36 CFR 1280.92 - When are the Presidential library museums open to the public?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... are also posted at http://www.archives.gov. (b) See 36 CFR 1253.3 for the operating hours of the... library museums open to the public? 1280.92 Section 1280.92 Parks, Forests, and Public Property NATIONAL... Use of Facilities in Presidential Libraries? § 1280.92 When are the Presidential library museums...

  15. The NCSS Presidential Addresses, 1970-2000: Perspectives on the Social Studies.

    ERIC Educational Resources Information Center

    Previte, Mark A., Ed.; Sheehan, James J., Ed.

    This collection of the National Council for the Social Studies (NCSS) presidential addresses seeks to provide a valuable window to NCSS and the field of social studies from 1970 to 2000. Following "Introduction to the NCSS Presidential Addresses, 1970-2000 (J. J. Sheehan), Volume 2 contains the following addresses: 1970: "Exploring the Meaning of…

  16. Presidential Leadership in Decision-Making: A Study of Three Historically Black Colleges and Universities

    ERIC Educational Resources Information Center

    Brown, Ronald E. L.

    2010-01-01

    This study investigates presidential leadership in decision-making at three private Historically Black Colleges and Universities (HBCUs) and compares understandings of presidential power within and among the three colleges given their unique institutional contexts. The research questions guiding this study include. How do the presidents of 3…

  17. On Becoming Themselves: The 1964-1968 Presidential Scholars 40 Years Later

    ERIC Educational Resources Information Center

    Kaufmann, Felice A.; Matthews, Dona J.

    2012-01-01

    Every year since 1964, approximately 120 high-school seniors have been selected for presidential recognition, from across the United States. As the first cohort of Presidential Scholars enters their 60s, we wanted to hear what they think about the roles that academic, professional, and personal achievement have played in their lives and to…

  18. 76 FR 13204 - Agency Information Collection Activities: Request for Entry or Departure for Flights to and From...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-10

    ... Departure for Flights to and From Cuba AGENCY: U.S. Customs and Border Protection (CBP), Department of... requirement concerning the Request for Entry or Departure for Flights to and from Cuba. This request for...: Title: Request for Entry or Departure for Flights To and From Cuba. OMB Number: 1651-0134. Form...

  19. 36 CFR 1254.14 - Are some procedures in regional archives and Presidential libraries different from those in the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... regional archives and Presidential libraries different from those in the Washington, DC, area? 1254.14... procedures in regional archives and Presidential libraries different from those in the Washington, DC, area... regional director of archival operations or Presidential library director indicates, you must follow...

  20. 41 CFR 301-70.201 - May we issue a blanket actual expense authorization for our employees during a Presidentially...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... actual expense authorization for our employees during a Presidentially-Declared Disaster? 301-70.201... authorization for our employees during a Presidentially-Declared Disaster? Yes. A blanket authorization... area subject to a Presidentially-Declared Disaster. These authorizations must apply to a...

  1. 36 CFR 1254.14 - Are some procedures in regional archives and Presidential libraries different from those in the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... regional archives and Presidential libraries different from those in the Washington, DC, area? 1254.14... procedures in regional archives and Presidential libraries different from those in the Washington, DC, area... regional director of archival operations or Presidential library director indicates, you must follow...

  2. Report on Alternative Models for Presidential Libraries Issued in Response to the Requirements of PL 110-404

    ERIC Educational Resources Information Center

    National Archives and Records Administration, 2009

    2009-01-01

    The Presidential Historical Records Preservation Act of 2008 [PL 110-404] requires that the Archivist of the United States submit to Congress a report on alternative models for Presidential archival depositories that: (1) Reduces the financial burden on the Federal Government; (2) Improves the preservation of Presidential records; and (3) Reduces…

  3. Abrupt shifts in Horn of Africa hydroclimate since the Last Glacial Maximum.

    PubMed

    Tierney, Jessica E; deMenocal, Peter B

    2013-11-15

    The timing and abruptness of the initiation and termination of the Early Holocene African Humid Period are subjects of ongoing debate, with direct consequences for our understanding of abrupt climate change, paleoenvironments, and early human cultural development. Here, we provide proxy evidence from the Horn of Africa region that documents abrupt transitions into and out of the African Humid Period in northeast Africa. Similar and generally synchronous abrupt transitions at other East African sites suggest that rapid shifts in hydroclimate are a regionally coherent feature. Our analysis suggests that the termination of the African Humid Period in the Horn of Africa occurred within centuries, underscoring the nonlinearity of the region's hydroclimate. PMID:24114782

  4. Scheduling and Delivering Aircraft to Departure Fixes in the NY Metroplex with Controller-Managed Spacing Tools

    NASA Technical Reports Server (NTRS)

    Chevalley, Eric; Parke, Bonny; Kraut, Josh M.; Bienert, Nancy; Omar, Faisal; Palmer, Everett A.

    2015-01-01

    In this paper, successful Time-Based Flow Management (TBFM) scheduling systems for arrivals are considered and adapted to apply to departures. We present a concept of operations that integrates Controller-Managed Spacing tools for departures (CMS-D) with existing tactical departure scheduling tools to coordinate demand at departure fixes in a metroplex environment. We tested our concept in a Human-in-the-Loop simulation and compared the effect of two scheduling conditions: 1) "Departure Scheduling" consisting of an emulation of the Integrated Departure and Arrival Capability (IDAC) where Towers and a Planner (Traffic Management Coordinator at the appropriate facility) coordinate aircraft scheduled takeoff times to departure fixes; and 2) "Arrival Sensitive Departure Scheduling" where, in addition, the Tower and Planner also consider arrival Scheduled Time of Arrivals (STAs) at the airport's dependent runway. Results indicate little difference between the two scheduling conditions, but a large difference between the No Tools and the two scheduling conditions with CMS-D tools. The scheduling/CMS-D tools conditions markedly reduced heading, speed clearances, and workload for controllers who were merging flows at the departure fixes. In the tool conditions, departure controllers conditioned departures earlier rather than later when aircraft were tied near the departure fixes. In the scheduling/CMS-D tools conditions, departures crossed the departure fixes 50 seconds earlier and with an 8% error rate (consisting of time ahead or behind desired time of arrival) compared to a 19% error rate in the No Tool condition. Two exploratory runs showed that similar beneficial effects can be obtained only with the CMS-D tools without scheduling takeoff times, but at the cost of a somewhat higher workload for controllers, indicating the benefits of pre-departure scheduling of aircraft with minimal delays. Hence, we found that CMS-D tools were very beneficial in the metroplex

  5. Effects of a Presidential Candidate's Comments on HPV Vaccine.

    PubMed

    Zucker, Rachel A; Reiter, Paul L; Mayer, Melissa K; Brewer, Noel T

    2015-01-01

    During and after the 2011 Republican presidential debate, a candidate questioned the safety of HPV vaccine. The authors aimed to determine the effect of these comments on parents. A national sample of 327 parents with adolescent sons ages 11-17 years completed online surveys in fall 2010 (baseline, about 1 year before the debate) and 2011 (follow-up, about 1 month after the debate). The authors used regression models to examine the association of parents' awareness of the candidate's comments with HPV vaccine initiation among their sons, their willingness to get sons free HPV vaccine, and their beliefs about potential harms of HPV vaccine. Overall, 17% of parents reported hearing about the Republican presidential candidate's comments about HPV vaccine. Parents aware of the comments had a larger increase between baseline and follow-up in the belief that HPV vaccine might cause short-term health problems compared with parents who were not aware. Although the candidate's comments may have increased some parents' beliefs about the short-term harms of HPV vaccine, the comments had no effect on other beliefs, willingness to vaccinate, or behavior. Having accurate information about HPV vaccine that is readily available to the public during such controversies may diminish their effect. PMID:25950109

  6. 76 FR 16686 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-25

    ... Policies and Procedures (44 FR 11034; February 26, 1979); and (3) does not warrant preparation of a... Minimums and Obstacle Departure Procedures; Miscellaneous Amendments AGENCY: Federal Aviation... Standard Instrument Approach Procedures (SIAPs) and associated Takeoff Minimums and Obstacle...

  7. 30 CFR 250.409 - May I obtain departures from these drilling requirements?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations... discuss the departure you are requesting in your APD (see § 250.414(h)). Applying for a Permit To Drill...

  8. 30 CFR 250.409 - May I obtain departures from these drilling requirements?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations General Requirements § 250.409 May I obtain departures from these...)). Applying for a Permit To Drill...

  9. 30 CFR 250.142 - How do I receive approval for departures?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF General... to the operating requirements. You may apply for a departure by writing to the District Manager...

  10. 30 CFR 250.142 - How do I receive approval for departures?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF General... to the operating requirements. You may apply for a departure by writing to the District Manager...

  11. 30 CFR 250.142 - How do I receive approval for departures?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF General... to the operating requirements. You may apply for a departure by writing to the District Manager...

  12. Abrupt Atmospheric Methane Increases Associated With Hudson Strait Heinrich Events

    NASA Astrophysics Data System (ADS)

    Rhodes, R.; Brook, E.; Chiang, J. C. H.; Blunier, T.; Maselli, O. J.; McConnell, J. R.; Romanini, D.; Severinghaus, J. P.

    2015-12-01

    The drivers of abrupt climate change during the Last Glacial Period are not well understood. While Dansgaard-Oeschger (DO) cycles are thought to be linked to variations in the strength of the Atlantic Meridional Ocean Circulation (AMOC), it is not clear how or if Heinrich Events—extensive influxes of icebergs into the North Atlantic Ocean that impacted global climate and biogeochemistry—are related. An enduring problem is the difficultly in dating iceberg rafted debris deposits that typically lack foraminifera. Here we present an ultra-high resolution record of methane from the West Antarctic Ice Sheet Divide ice core at unprecedented, continuous temporal resolution from 67.2-9.8 ka BP, which we propose constrains the timing of Heinrich events. Our methane record essentially mirrors Greenland ice core stable isotope variability across D-O events, except during Heinrich stadials 1, 2, 4 and 5. Partway through these stadials only, methane increases abruptly and rapidly, as at the onset of a D-O event but Greenland temperature exhibits no equivalent response. Speleothem records exhibit signatures of drought in the Northern extra-tropics and intensified monsoonal activity over South America at these times. We use a simple heuristic model to propose that cold air temperatures and extensive sea ice in the North, resulting from Heinrich events, caused extreme reorganization of tropical hydroclimate. This involved curtailment of the seasonal northerly migration of tropical rain belts, leading to intensification of rainfall over Southern Hemisphere tropical wetlands, thus allowing production of excess methane relative to a 'normal' Greenland stadial. We note that this mechanism can operate if AMOC is already in a slowed state when a Heinrich event occurs, as paleo-evidence suggests it was. Heinrich events and associated sea ice cover would therefore act to prolong the duration of this AMOC state. Our findings place the big four Heinrich events of Hudson Strait origin

  13. The Stiles-Crawford Effect: spot-size ratio departure in retinitis pigmentosa

    NASA Astrophysics Data System (ADS)

    Sharma, Nachieketa K.; Lakshminarayanan, Vasudevan

    2016-04-01

    The Stiles-Crawford effect of the first kind is the retina's compensative response to loss of luminance efficiency for oblique stimulation manifested as the spot-size ratio departure from the perfect power coupling for a normal human eye. In a retinitis pigmentosa eye (RP), the normal cone photoreceptor morphology is affected due to foveal cone loss and disrupted cone mosaic spatial arrangement with reduction in directional sensitivity. We show that the flattened Stiles-Crawford function (SCF) in a RP eye is due to a different spot-size ratio departure profile, that is, for the same loss of luminance efficiency, a RP eye has a smaller departure from perfect power coupling compared to a normal eye. Again, the difference in spot-size ratio departure increases from the centre towards the periphery, having zero value for axial entry and maximum value for maximum peripheral entry indicating dispersal of photoreceptor alignment which prevents the retina to go for a bigger compensative response as it lacks both in number and appropriate cone morphology to tackle the loss of luminance efficiency for oblique stimulation. The slope of departure profile also testifies to the flattened SCF for a RP eye. Moreover, the discrepancy in spot-size ratio departure between a normal and a RP eye is shown to have a direct bearing on the Stiles-Crawford diminution of visibility.

  14. Statistical approaches for identifying air pollutant mixtures associated with aircraft departures at Los Angeles International Airport.

    PubMed

    Diez, David M; Dominici, Francesca; Zarubiak, Darcy; Levy, Jonathan I

    2012-08-01

    Aircraft departures emit multiple pollutants common to other near-airport sources, making it challenging to determine relative source contributions. While there may not be unique tracers of aircraft emissions, examination of multipollutant concentration patterns in combination with flight activity can facilitate source attribution. In this study, we examine concentrations of continuously monitored air pollutants measured in 2008 near a departure runway at Los Angeles International Airport (LAX), considering single-pollutant associations with landing and takeoff (LTO) of the aircraft (LTO activity, weighted by LTO cycle fuel burn), as well as multipollutant predictors of binary LTO activity. In the single-pollutant analyses, one-minute average concentrations of carbon monoxide, carbon dioxide, nitrogen oxides, and sulfur dioxide are positively associated with fuel burn-weighted departures on the runway proximate to the monitor, whereas ozone is negatively associated with fuel burn-weighted departures. In analyses in which the flight departure is predicted by pollutant concentrations, carbon dioxide and nitrogen oxides are the best individual predictors, but including all five pollutants greatly increases the power of prediction compared to single-pollutant models. Our results demonstrate that air pollution impacts from aircraft departures can be isolated using time-resolved monitoring data, and that combinations of simultaneously measured pollutants can best identify contributions from flight activity.

  15. Anticipating abrupt shifts in temporal evolution of probability of eruption

    NASA Astrophysics Data System (ADS)

    Rohmer, Jeremy; Loschetter, Annick

    2016-04-01

    Estimating the probability of eruption by jointly accounting for different sources of monitoring parameters over time is a key component for volcano risk management. In the present study, we are interested in the transition from a state of low-to-moderate probability value and to the one of high probability value: the latter value generally supports the call for evacuation. By using the data of MESIMEX exercise at the Vesuvius volcano, we investigated the potential for time-varying indicators related to the correlation structure or to the variability of the probability time series for detecting in advance this critical transition. We found that changes in the power spectra and in the standard deviation estimated over a rolling time window both present an abrupt increase, which marks the approaching shift. Our numerical experiments revealed that the transition from an eruption probability of 10-15% to >70% could be identified up 4 hours in advance, ~2.5 days before the evacuation call (decided for an eruption probability >80% during the MESIMEX exercise). This additional lead time could be useful to place different key services (e.g., emergency services for vulnerable groups, commandeering additional transportation means, etc.) on a higher level of alert before the actual call for evacuation.

  16. Anticipating abrupt shifts in temporal evolution of probability of eruption

    NASA Astrophysics Data System (ADS)

    Rohmer, J.; Loschetter, A.

    2016-04-01

    Estimating the probability of eruption by jointly accounting for different sources of monitoring parameters over time is a key component for volcano risk management. In the present study, we are interested in the transition from a state of low-to-moderate probability value to a state of high probability value. By using the data of MESIMEX exercise at the Vesuvius volcano, we investigated the potential for time-varying indicators related to the correlation structure or to the variability of the probability time series for detecting in advance this critical transition. We found that changes in the power spectra and in the standard deviation estimated over a rolling time window both present an abrupt increase, which marks the approaching shift. Our numerical experiments revealed that the transition from an eruption probability of 10-15% to > 70% could be identified up to 1-3 h in advance. This additional lead time could be useful to place different key services (e.g., emergency services for vulnerable groups, commandeering additional transportation means, etc.) on a higher level of alert before the actual call for evacuation.

  17. Abrupt climate change and the decline of Indus urbanism

    NASA Astrophysics Data System (ADS)

    Hodell, D. A.; Dixit, Y.; Petrie, C. A.

    2012-12-01

    Climate change has been suggested as a cause for the decline of the cities of the Indus Civilization, which is believed to have begun ~4.0 to 3.9 ky B.P. Previous studies have centered on paleoclimatic records obtained from areas outside the geographic limits of the Indus Civilization, raising questions about their suitability for evaluating past climate-cultural linkages. Here we report a detailed climate record from paleolake Kotla Dahar, Haryana (28°00'095'' N, 76°57'173'' E), located at the eastern edge of the distribution of Indus settlements and ~100km to the east of the city-site of Rakhigarhi in NW India. Regional hydrologic changes are inferred using oxygen-isotope measurements of gastropod aragonite from a 2.88-m sediment section. A permanent ~4‰ increase in δ18O of shell aragonite occurred at ~4.1±0.1 ky B.P., marking an abrupt increase in evaporation/precipitation in the lake catchment. These data provide evidence for a weakening of the monsoon and shift toward drier climate on the plains of northwest (NW) India at ~4.1±0.1 ky B.P. Decreased monsoon rainfall at this time may have been linked to increased ENSO variability, and supports a possible role of climate in the transformation of the Indus Civilization from an urbanized (mature or urban Indus) to a rural (post-urban) society.

  18. Dynamic response of desert wetlands to abrupt climate change

    PubMed Central

    Springer, Kathleen B.; Manker, Craig R.; Pigati, Jeffrey S.

    2015-01-01

    Desert wetlands are keystone ecosystems in arid environments and are preserved in the geologic record as groundwater discharge (GWD) deposits. GWD deposits are inherently discontinuous and stratigraphically complex, which has limited our understanding of how desert wetlands responded to past episodes of rapid climate change. Previous studies have shown that wetlands responded to climate change on glacial to interglacial timescales, but their sensitivity to short-lived climate perturbations is largely unknown. Here, we show that GWD deposits in the Las Vegas Valley (southern Nevada, United States) provide a detailed and nearly complete record of dynamic hydrologic changes during the past 35 ka (thousands of calibrated 14C years before present), including cycles of wetland expansion and contraction that correlate tightly with climatic oscillations recorded in the Greenland ice cores. Cessation of discharge associated with rapid warming events resulted in the collapse of entire wetland systems in the Las Vegas Valley at multiple times during the late Quaternary. On average, drought-like conditions, as recorded by widespread erosion and the formation of desert soils, lasted for a few centuries. This record illustrates the vulnerability of desert wetland flora and fauna to abrupt climate change. It also shows that GWD deposits can be used to reconstruct paleohydrologic conditions at millennial to submillennial timescales and informs conservation efforts aimed at protecting these fragile ecosystems in the face of anthropogenic warming. PMID:26554007

  19. Abrupt drainage cycles of the Fennoscandian Ice Sheet

    PubMed Central

    Soulet, Guillaume; Ménot, Guillemette; Bayon, Germain; Rostek, Frauke; Ponzevera, Emmanuel; Toucanne, Samuel; Lericolais, Gilles; Bard, Edouard

    2013-01-01

    Continental ice sheets are a key component of the Earth’s climate system, but their internal dynamics need to be further studied. Since the last deglaciation, the northern Eurasian Fennoscandian Ice Sheet (FIS) has been connected to the Black Sea (BS) watershed, making this basin a suitable location to investigate former ice-sheet dynamics. Here, from a core retrieved in the BS, we combine the use of neodymium isotopes, high-resolution elemental analysis, and biomarkers to trace changes in sediment provenance and river runoff. We reveal cyclic releases of meltwater originating from Lake Disna, a proglacial lake linked to the FIS during Heinrich Stadial 1. Regional interactions within the climate–lake–FIS system, linked to changes in the availability of subglacial water, led to abrupt drainage cycles of the FIS into the BS watershed. This phenomenon raised the BS water level by ∼100 m until the sill of the Bosphorus Strait was reached, flooding the vast northwestern BS shelf and deeply affecting the hydrology and circulation of the BS and, probably, of the Marmara and Aegean Seas. PMID:23569264

  20. Climate oscillations and abrupt changes in C14 data

    NASA Astrophysics Data System (ADS)

    Kuznetsova, T. V.; Tsirulnik, L. B.

    2004-01-01

    The radiocarbon series are analysed by a method of non-linear spectral analysis to detect time intervals of appearance of non-stationary oscillations of large amplitude, and the times of abrupt changes of their oscillation regime. The analysis shows that the most powerful cycles of the spectra can be interpreted in terms of periods (and their respective higher harmonics) of astronomical origin. An intense stationary sinusoid from the spectrum with period T˜6500 yr, the 4th harmonic of the period of equinox precession, correlates with the time variations of the geomagnetic dipole moment. The most powerful non-stationary sinusoid with mean period T=2230 yr, reflects oscillations in C14 data related to the non-dipole part of the geomagnetic field, and correlates with periods of climate warming/cooling. The apparent regularities that can be inferred in the interaction of such two powerful cycles (i.e. stationary and non-stationary parts of the uniform mechanism of the geomagnetic field generation) permit to forecast a tendency of the climate changes. A possible physical mechanism is presented based on a possible transformation, of some signals caused by perturbation of the tidal forces of astronomical origin (that can arise along the orbit of the Earth), into effects that control geophysical systems through small variations of the dissipative parameters of a dynamo system.

  1. Detecting and isolating abrupt changes in linear switching systems

    NASA Astrophysics Data System (ADS)

    Nazari, Sohail; Zhao, Qing; Huang, Biao

    2015-04-01

    In this paper, a novel fault detection and isolation (FDI) method for switching linear systems is developed. All input and output signals are assumed to be corrupted with measurement noises. In the proposed method, a 'lifted' linear model named as stochastic hybrid decoupling polynomial (SHDP) is introduced. The SHDP model governs the dynamics of the switching linear system with all different modes, and is independent of the switching sequence. The error-in-variable (EIV) representation of SHDP is derived, and is used for the fault residual generation and isolation following the well-adopted local approach. The proposed FDI method can detect and isolate the fault-induced abrupt changes in switching models' parameters without estimating the switching modes. Furthermore, in this paper, the analytical expressions of the gradient vector and Hessian matrix are obtained based on the EIV SHDP formulation, so that they can be used to implement the online fault detection scheme. The performance of the proposed method is then illustrated by simulation examples.

  2. Abrupt Schottky Junctions in Al/Ge Nanowire Heterostructures

    PubMed Central

    2015-01-01

    In this Letter we report on the exploration of axial metal/semiconductor (Al/Ge) nanowire heterostructures with abrupt interfaces. The formation process is enabled by a thermal induced exchange reaction between the vapor–liquid–solid grown Ge nanowire and Al contact pads due to the substantially different diffusion behavior of Ge in Al and vice versa. Temperature-dependent I–V measurements revealed the metallic properties of the crystalline Al nanowire segments with a maximum current carrying capacity of about 0.8 MA/cm2. Transmission electron microscopy (TEM) characterization has confirmed both the composition and crystalline nature of the pure Al nanowire segments. A very sharp interface between the ⟨111⟩ oriented Ge nanowire and the reacted Al part was observed with a Schottky barrier height of 361 meV. To demonstrate the potential of this approach, a monolithic Al/Ge/Al heterostructure was used to fabricate a novel impact ionization device. PMID:26052733

  3. Dynamic response of desert wetlands to abrupt climate change.

    PubMed

    Springer, Kathleen B; Manker, Craig R; Pigati, Jeffrey S

    2015-11-24

    Desert wetlands are keystone ecosystems in arid environments and are preserved in the geologic record as groundwater discharge (GWD) deposits. GWD deposits are inherently discontinuous and stratigraphically complex, which has limited our understanding of how desert wetlands responded to past episodes of rapid climate change. Previous studies have shown that wetlands responded to climate change on glacial to interglacial timescales, but their sensitivity to short-lived climate perturbations is largely unknown. Here, we show that GWD deposits in the Las Vegas Valley (southern Nevada, United States) provide a detailed and nearly complete record of dynamic hydrologic changes during the past 35 ka (thousands of calibrated (14)C years before present), including cycles of wetland expansion and contraction that correlate tightly with climatic oscillations recorded in the Greenland ice cores. Cessation of discharge associated with rapid warming events resulted in the collapse of entire wetland systems in the Las Vegas Valley at multiple times during the late Quaternary. On average, drought-like conditions, as recorded by widespread erosion and the formation of desert soils, lasted for a few centuries. This record illustrates the vulnerability of desert wetland flora and fauna to abrupt climate change. It also shows that GWD deposits can be used to reconstruct paleohydrologic conditions at millennial to submillennial timescales and informs conservation efforts aimed at protecting these fragile ecosystems in the face of anthropogenic warming. PMID:26554007

  4. Dynamic response of desert wetlands to abrupt climate change

    USGS Publications Warehouse

    Springer, Kathleen; Manker, Craig; Pigati, Jeff

    2015-01-01

    Desert wetlands are keystone ecosystems in arid environments and are preserved in the geologic record as groundwater discharge (GWD) deposits. GWD deposits are inherently discontinuous and stratigraphically complex, which has limited our understanding of how desert wetlands responded to past episodes of rapid climate change. Previous studies have shown that wetlands responded to climate change on glacial to interglacial timescales, but their sensitivity to short-lived climate perturbations is largely unknown. Here, we show that GWD deposits in the Las Vegas Valley (southern Nevada, United States) provide a detailed and nearly complete record of dynamic hydrologic changes during the past 35 ka (thousands of calibrated 14C years before present), including cycles of wetland expansion and contraction that correlate tightly with climatic oscillations recorded in the Greenland ice cores. Cessation of discharge associated with rapid warming events resulted in the collapse of entire wetland systems in the Las Vegas Valley at multiple times during the late Quaternary. On average, drought-like conditions, as recorded by widespread erosion and the formation of desert soils, lasted for a few centuries. This record illustrates the vulnerability of desert wetland flora and fauna to abrupt climate change. It also shows that GWD deposits can be used to reconstruct paleohydrologic conditions at millennial to submillennial timescales and informs conservation efforts aimed at protecting these fragile ecosystems in the face of anthropogenic warming.

  5. Dynamic response of desert wetlands to abrupt climate change.

    PubMed

    Springer, Kathleen B; Manker, Craig R; Pigati, Jeffrey S

    2015-11-24

    Desert wetlands are keystone ecosystems in arid environments and are preserved in the geologic record as groundwater discharge (GWD) deposits. GWD deposits are inherently discontinuous and stratigraphically complex, which has limited our understanding of how desert wetlands responded to past episodes of rapid climate change. Previous studies have shown that wetlands responded to climate change on glacial to interglacial timescales, but their sensitivity to short-lived climate perturbations is largely unknown. Here, we show that GWD deposits in the Las Vegas Valley (southern Nevada, United States) provide a detailed and nearly complete record of dynamic hydrologic changes during the past 35 ka (thousands of calibrated (14)C years before present), including cycles of wetland expansion and contraction that correlate tightly with climatic oscillations recorded in the Greenland ice cores. Cessation of discharge associated with rapid warming events resulted in the collapse of entire wetland systems in the Las Vegas Valley at multiple times during the late Quaternary. On average, drought-like conditions, as recorded by widespread erosion and the formation of desert soils, lasted for a few centuries. This record illustrates the vulnerability of desert wetland flora and fauna to abrupt climate change. It also shows that GWD deposits can be used to reconstruct paleohydrologic conditions at millennial to submillennial timescales and informs conservation efforts aimed at protecting these fragile ecosystems in the face of anthropogenic warming.

  6. Changes in the timing of departure and arrival of Irish migrant waterbirds

    PubMed Central

    Geyer, Heather; Yu, Rong

    2015-01-01

    There have been many recent reports across Europe and North America of a change in the timing of arrival and departure of a range of migrant bird species to their breeding grounds. These studies have focused primarily on passerine birds and climate warming has been found to be one of the main drivers of earlier arrival and departure in spring. In Ireland, rising spring temperature has been shown to result in the earlier arrival of sub-Saharan passerine species and the early departure of the Whooper Swan. In order to investigate changes in spring arrival and departure dates of waterbirds to Ireland, we extracted latest dates as an indicator of the timing of departure of winter visitors (24 species) and earliest dates as an indicator of the timing of arrival of spring/summer migrants (2 species) from BirdWatch Ireland’s East Coast Bird reports (1980–2003). Three of the winter visitors showed evidence of later departure and one of earlier departure whereas one of the spring/summer visitors showed evidence of earlier arrival. In order to determine any influence of local temperature on these trends, we analysed data from two synoptic weather stations within the study area and found that spring (average February, March and April) air temperature significantly (P < 0.05) increased at a rate of 0.03 °C per year, which was strongly correlated with changes in latest and earliest records. We also tested the sensitivity of bird departure/arrival to temperature and found that Northern Pintail would leave 10 days earlier in response to a 1 °C increase in spring temperature. In addition, we investigated the impact of a large-scale circulation pattern, the North Atlantic Oscillation (NAO), on the timing of arrival and departure which correlated with both advances and delays in departure and arrival. We conclude that the impact of climate change on earliest and latest records of these birds is, as expected, species specific and that local temperature had less of an influence

  7. Changes in the timing of departure and arrival of Irish migrant waterbirds.

    PubMed

    Donnelly, Alison; Geyer, Heather; Yu, Rong

    2015-01-01

    There have been many recent reports across Europe and North America of a change in the timing of arrival and departure of a range of migrant bird species to their breeding grounds. These studies have focused primarily on passerine birds and climate warming has been found to be one of the main drivers of earlier arrival and departure in spring. In Ireland, rising spring temperature has been shown to result in the earlier arrival of sub-Saharan passerine species and the early departure of the Whooper Swan. In order to investigate changes in spring arrival and departure dates of waterbirds to Ireland, we extracted latest dates as an indicator of the timing of departure of winter visitors (24 species) and earliest dates as an indicator of the timing of arrival of spring/summer migrants (2 species) from BirdWatch Ireland's East Coast Bird reports (1980-2003). Three of the winter visitors showed evidence of later departure and one of earlier departure whereas one of the spring/summer visitors showed evidence of earlier arrival. In order to determine any influence of local temperature on these trends, we analysed data from two synoptic weather stations within the study area and found that spring (average February, March and April) air temperature significantly (P < 0.05) increased at a rate of 0.03 °C per year, which was strongly correlated with changes in latest and earliest records. We also tested the sensitivity of bird departure/arrival to temperature and found that Northern Pintail would leave 10 days earlier in response to a 1 °C increase in spring temperature. In addition, we investigated the impact of a large-scale circulation pattern, the North Atlantic Oscillation (NAO), on the timing of arrival and departure which correlated with both advances and delays in departure and arrival. We conclude that the impact of climate change on earliest and latest records of these birds is, as expected, species specific and that local temperature had less of an influence than

  8. The 2012 AANS Presidential Address. We are neurosurgery.

    PubMed

    McCormick, Paul C

    2012-12-01

    The theme of the 80th Annual Meeting of the American Association of Neurological Surgeons and the title of this presidential address, "We are neurosurgery," is a simple 3-word affirmation of who neurosurgeons are, what they have achieved, and how much there is yet to accomplish. Recent advances in neurobiology and the clinical neurosciences have brought an unprecedented understanding of the human nervous system in both health and disease. As a specialty, neurosurgery has translated knowledge, expanded techniques, and incorporated technology to exponentially expand the science and scope of neurosurgical practice. However, the rapidly advancing, divergently evolving growth of neurosurgery has had profound effects on all aspects of neurosurgery. In this address, the author examines the contemporary meaning of the annual meeting's theme as it relates to the science, practice, specialty, and profession of neurosurgery, as well as the neurosurgeon. In doing so, the author reveals his interpretation of "We are neurosurgery," which he hopes will have an effect on others.

  9. Did Hurricane Sandy influence the 2012 US presidential election?

    PubMed

    Hart, Joshua

    2014-07-01

    Despite drawing on a common pool of data, observers of the 2012 presidential campaign came to different conclusions about whether, how, and to what extent "October surprise" Hurricane Sandy influenced the election. The present study used a mixed correlational and experimental design to assess the relation between, and effect of, the salience of Hurricane Sandy on attitudes and voting intentions regarding President Barack Obama and Mitt Romney in a large sample of voting-aged adults. Results suggest that immediately following positive news coverage of Obama's handling of the storm's aftermath, Sandy's salience positively influenced attitudes toward Obama, but that by election day, reminders of the hurricane became a drag instead of a boon for the President. In addition to theoretical implications, this study provides an example of how to combine methodological approaches to help answer questions about the impact of unpredictable, large-scale events as they unfold. PMID:24767585

  10. Did Hurricane Sandy influence the 2012 US presidential election?

    PubMed

    Hart, Joshua

    2014-07-01

    Despite drawing on a common pool of data, observers of the 2012 presidential campaign came to different conclusions about whether, how, and to what extent "October surprise" Hurricane Sandy influenced the election. The present study used a mixed correlational and experimental design to assess the relation between, and effect of, the salience of Hurricane Sandy on attitudes and voting intentions regarding President Barack Obama and Mitt Romney in a large sample of voting-aged adults. Results suggest that immediately following positive news coverage of Obama's handling of the storm's aftermath, Sandy's salience positively influenced attitudes toward Obama, but that by election day, reminders of the hurricane became a drag instead of a boon for the President. In addition to theoretical implications, this study provides an example of how to combine methodological approaches to help answer questions about the impact of unpredictable, large-scale events as they unfold.

  11. Wishful thinking in the 2008 U.S. presidential election.

    PubMed

    Krizan, Zlatan; Miller, Jeffrey C; Johar, Omesh

    2010-01-01

    In elections, political preferences are strongly linked to the expectations of the electoral winner-people usually expect their favorite candidate to win. This link could be driven by wishful thinking (a biasing influence of preferences), driven by a biasing influence of expectations on one's wishes, or produced spuriously. To examine these competing possibilities in the 2008 U.S. presidential election, a longitudinal study assessed uncommitted young voters' electoral expectations and preferences over four time points during the month before the election. The findings indicated clear support for wishful thinking: Over time, people's preferences shaped their expectations, but the reverse was not the case. Moreover, these relations were larger among those more strongly identified with their political party and held even when perceptions of general candidate popularity were taken into account. Finally, changes in electoral expectations were consequential, as they shaped disappointment in the electoral results even after taking candidate preferences into account.

  12. From Abrupt Change to the Future (Hans Oeschger Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Stocker, T.

    2009-04-01

    The award of the Oeschger Medal 2009 is a particular honor and pleasure for me as I was given the chance to take over from Hans Oeschger the lead of a wonderful Institute at the University of Bern in 1993. Very apprehensive first, in front of the huge expectations and challenges, I quickly found dear colleagues, close collaborators and extremely supportive staff who all dedicated their time and creativity to work for the common goal of better understanding the Earth System, its variations in the past and its sensitivity to perturbations that man is inflicting on it today. Although met with innate skepticism first by the experimental physicists, our efforts in modelling, particularly the approach of using climate models of reduced complexity, quickly paid off and provided added value to the hard won data and measurements from polar ice cores. It is clear that modelling in such a diverse environment is so much more stimulating and enriching than working on a sophisticated parameterisation in a big modelling centre. Simple models have suggested that the Earth System may have limited stability and that rather fundamental changes could be triggered by the increase of greenhouse gases. However, it is the unique results from polar ice cores, particularly from Greenland that showed that, indeed, the Earth System has limited stability and can react in extremely abrupt ways to changes in forcing. Likewise, the Antarctic ice cores have provided one of the corner stones of our knowledge about climate change: Concentrations of CO2 are today 29% higher than ever during the last 800,000 years. These two fundamental insights from the paleoclimatic archive call for accelerated research into the sensitivity of the climate system and its components to perturbations, as well as the investigation of feedback mechanisms in the biogeochemical cycles that are disturbed by the input of CO2 into the atmosphere by burning fossil fuels and land use change. Our research has only scratched the

  13. Wildfire responses to abrupt climate change in North America.

    PubMed

    Marlon, J R; Bartlein, P J; Walsh, M K; Harrison, S P; Brown, K J; Edwards, M E; Higuera, P E; Power, M J; Anderson, R S; Briles, C; Brunelle, A; Carcaillet, C; Daniels, M; Hu, F S; Lavoie, M; Long, C; Minckley, T; Richard, P J H; Scott, A C; Shafer, D S; Tinner, W; Umbanhowar, C E; Whitlock, C

    2009-02-24

    It is widely accepted, based on data from the last few decades and on model simulations, that anthropogenic climate change will cause increased fire activity. However, less attention has been paid to the relationship between abrupt climate changes and heightened fire activity in the paleorecord. We use 35 charcoal and pollen records to assess how fire regimes in North America changed during the last glacial-interglacial transition (15 to 10 ka), a time of large and rapid climate changes. We also test the hypothesis that a comet impact initiated continental-scale wildfires at 12.9 ka; the data do not support this idea, nor are continent-wide fires indicated at any time during deglaciation. There are, however, clear links between large climate changes and fire activity. Biomass burning gradually increased from the glacial period to the beginning of the Younger Dryas. Although there are changes in biomass burning during the Younger Dryas, there is no systematic trend. There is a further increase in biomass burning after the Younger Dryas. Intervals of rapid climate change at 13.9, 13.2, and 11.7 ka are marked by large increases in fire activity. The timing of changes in fire is not coincident with changes in human population density or the timing of the extinction of the megafauna. Although these factors could have contributed to fire-regime changes at individual sites or at specific times, the charcoal data indicate an important role for climate, and particularly rapid climate change, in determining broad-scale levels of fire activity.

  14. Abrupt changes in North American climate during early Holocene times

    NASA Astrophysics Data System (ADS)

    Hu, F. S.; Slawinski, D.; Wright, H. E.; Ito, E.; Johnson, R. G.; Kelts, K. R.; McEwan, R. F.; Boedigheimer, A.

    1999-07-01

    Recent studies of the Greenland ice cores have offered many insights into Holocene climatic dynamics at decadal to century timescales. Despite the abundance of continental records of Holocene climate, few have sufficient chronological control and sampling resolution to compare with the Greenland findings. Butannually laminated sediments (varves) from lakes can provide high-resolution continental palaeoclimate data with secure chronologies. Here we present analyses of varved sediments from Deep Lake in Minnesota, USA. Trends in the stable oxygen-isotope composition of the sedimentary carbonate indicate a pronounced climate cooling from 8.9 to 8.3kyr before present, probably characterized by increased outbreaks of polar air, decreased precipitation temperatures, and a higher fraction of the annual precipitation falling as snow. The abrupt onset of this climate reversal, over several decades, was probably caused by a reorganization of atmospheric circulation and cooling of the Arctic airmass in summer that resulted from the final collapse of the Laurentide ice near Hudson Bay and the discharge of icebergs from the Quebec and Keewatin centres into the Tyrell Sea. The timing and duration of this climate reversal suggest that it is distinct from the prominent widespread cold snap that occurred 8,200 years ago in Greenland and other regions,,. No shifts in the oxygen-isotope composition of sediment carbonate occurred at 8.2kyr before present at Deep Lake, but varve thickness increased dramatically, probably as a result of increased deposition of aeolian dust. Taken together, our data suggest that two separate regional-scale climate reversals occurred between 9,000 and 8,000 years ago, and that they were driven by different mechanisms.

  15. 75 FR 37780 - Proposed Waivers and Extensions of Project Periods: Presidential Academies and Congressional...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-30

    ... for Students of American History and Civics Education. These regulations, respectively, generally... five-year grants funded under the Presidential Academies for American History and Civics Education... under the Congressional Academies for Students of American History and Civics Education would...

  16. 36 CFR 1280.92 - When are the Presidential library museums open to the public?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... visit the NARA Web site at http://www.archives.gov. Hours for the Presidential libraries' research rooms are also posted at http://www.archives.gov. (b) See 36 CFR 1253.3 for the operating hours of...

  17. 77 FR 29391 - Advisory Committee on the Presidential Library-Foundation Partnerships

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-17

    ... its strategic planning process as it relates to Presidential Libraries. The meeting will be open to... procedures, the name and telephone number of individuals planning to attend must be submitted to the...

  18. Voter Learning in the 1992 Presidential Election: Did the "Nontraditional" Media and Debates Matter?

    ERIC Educational Resources Information Center

    Weaver, David; Drew, Dan

    1995-01-01

    Finds that the nontraditional media of television talk shows and morning network shows did not contribute significantly to greater knowledge of candidate issue positions, greater intention to vote, or higher levels of interest in the 1992 presidential election campaign. (SR)

  19. Looking for "The Vision Thing": The Rhetoric of Leadership in the 1992 Presidential Election.

    ERIC Educational Resources Information Center

    Wendt, Ronald F.; Fairhurst, Gail T.

    1994-01-01

    Examines four interrelated organizational models of charisma and the debate that has accompanied them. Uses the models to analyze the rhetoric of leadership of George Bush, Bill Clinton, and Ross Perot in the 1992 presidential campaign. (SR)

  20. 78 FR 58861 - Presidential Determination With Respect to Foreign Governments' Efforts Regarding Trafficking in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-25

    .... (Presidential Sig.) THE WHITE HOUSE, Washington, September 17, 2013. [FR Doc. 2013-23463 Filed 9-24-13; 8:45 am..., Saudi Arabia, Uzbekistan, and Yemen that provision to these countries' governments of all...

  1. 77 FR 58921 - Presidential Determination With Respect to Foreign Governments' Efforts Regarding Trafficking in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-24

    ... it in the Federal Register. (Presidential Sig.) THE WHITE HOUSE, Washington, September 14, 2012. [FR... Algeria, the Central African Republic, Kuwait, Libya, Papua New Guinea, Saudi Arabia, and Yemen...

  2. 76 FR 62599 - Presidential Determination With Respect to Foreign Governments' Efforts Regarding Trafficking in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    .... (Presidential Sig.) THE WHITE HOUSE, Washington, September 30, 2011 [FR Doc. 2011-26333 Filed 10-7-11; 8:45 am..., Mauritania, Micronesia, Papua New Guinea, Saudi Arabia, Sudan, Turkmenistan, and Yemen that provision...

  3. 75 FR 43029 - The Presidential POWER Initiative: Protecting Our Workers and Ensuring Reemployment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ... Register. (Presidential Sig.) THE WHITE HOUSE, Washington, July 19, 2010 [FR Doc. 2010-18176 Filed 7-21-10... by setting more aggressive performance targets, encouraging the collection and analysis of data...

  4. 77 FR 3369 - Presidential Determination on the Eligibility of South Sudan To Receive Defense Articles and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-24

    ... arrange for the publication of this determination in the Federal Register. (Presidential Sig.) THE WHITE HOUSE, Washington, January 6, 2012 [FR Doc. 2012-1545 Filed 1-23-12; 8:45 am] Billing code 4710-10-P...

  5. The Ironist and Hypocrite as Presidential Symbols: A Nixon-Kennedy Analog.

    ERIC Educational Resources Information Center

    Kaufer, David S.

    1979-01-01

    Discusses the self-disparaging ironist and the hypocrite as symbols of power in contemporary American politics. Contrasts the presidential images of Richard Nixon and John Kennedy who exemplify, respectively, hypocritical and ironical power-holders. (PD)

  6. Maternal Sleep Duration and Complaints of Vital Exhaustion during Pregnancy is Associated with Placental Abruption

    PubMed Central

    Qiu, Chunfang; Sanchez, Sixto E.; Gelaye, Bizu; Enquobahrie, Daniel A.; Ananth, Cande V.; Williams, Michelle A.

    2014-01-01

    OBJECTIVE Sleep disorders are associated with cardiovascular complications and preterm delivery (PTD). Insufficient sleep results in metabolic alterations and increased inflammation, both known to contribute to placental abruption (abruption), a determinant of PTD. We examined associations of abruption with sleep duration and complaints of vital exhaustion. METHODS The study included 164 abruption cases and 160 controls in a multicenter study in Peru. Data on habitual sleep duration and vital exhaustion during the first 6 months of pregnancy were elicited during interviews conducted following delivery. Women were categorized according to short, normal and long sleep duration (≤6, 7-8 and ≥9 h); and frequency of feeling exhausted. Odds ratios (OR) and 95% confidence intervals (CI) were calculated. RESULTS Short and long sleep durations were associated with increased odds of abruption. The ORs of abruption in relation to short (≤6 h) and long (≥9 h) sleep duration were 2.0 (95%CI 1.1-3.7) and 2.1 (95%CI 1.1-4.1), compared with normal sleep duration (7-8 h). Complaints of vital exhaustion were also associated with abruption (OR=2.37; 95%CI 1.46-3.85), and were independent of sleep duration. CONCLUSION We extend the existing literature and support the thesis that maternal sleep habits and disorders should be assessed among pregnant women. PMID:24749793

  7. Detecting abrupt dynamic change based on changes in the fractal properties of spatial images

    NASA Astrophysics Data System (ADS)

    Liu, Qunqun; He, Wenping; Gu, Bin; Jiang, Yundi

    2016-08-01

    Many abrupt climate change events often cannot be detected timely by conventional abrupt detection methods until a few years after these events have occurred. The reason for this lag in detection is that abundant and long-term observational data are required for accurate abrupt change detection by these methods, especially for the detection of a regime shift. So, these methods cannot help us understand and forecast the evolution of the climate system in a timely manner. Obviously, spatial images, generated by a coupled spatiotemporal dynamical model, contain more information about a dynamic system than a single time series, and we find that spatial images show the fractal properties. The fractal properties of spatial images can be quantitatively characterized by the Hurst exponent, which can be estimated by two-dimensional detrended fluctuation analysis (TD-DFA). Based on this, TD-DFA is used to detect an abrupt dynamic change of a coupled spatiotemporal model. The results show that the TD-DFA method can effectively detect abrupt parameter changes in the coupled model by monitoring the changing in the fractal properties of spatial images. The present method provides a new way for abrupt dynamic change detection, which can achieve timely and efficient abrupt change detection results.

  8. The use of low departure aspheric surfaces in high quality wide angle lenses

    NASA Astrophysics Data System (ADS)

    Dalzell, Kristen E.; Jonas, Reginald P.; Wallace, Brian P.

    2015-09-01

    Modern lens designs for digital sensors, such as those required in medium volumes for cinematography, often require the use of one or two high departure aspheric surfaces. With departures from best fit sphere of up to a few millimeters, the use of such surfaces are accompanied by a number of consequences: high cost metrology, very tight opto-mechanical tolerances and image artifacts due to the sub-aperture grinding and polishing process. Previously we examined the use of multiple aspheric surfaces with very low departures from best fit sphere (BFS) and concluded that advantages may be gained in standard and telephoto lenses, but not in wide angle lens designs1. In this work we consider the potential benefits of low departure aspheric surfaces, as applied to wide angle lenses in particular. We review the number, placement, and nature of aspheric surfaces in some wide angle lens design examples, and look at the potential to redesign with an increased number of low departure aspheric surfaces that have the potential to be manufactured without the need for computer generated holograms (CGH's). The use and limitations of modern interferometers capable of measuring aspheric surfaces without the use of CGH's will be considered. In one example we examine the performance, manufacturing, and cost perspective, paying particular attention to testing and mechanical alignment tolerances.

  9. Flight Departure Delay and Rerouting Under Uncertainty in En Route Convective Weather

    NASA Technical Reports Server (NTRS)

    Mukherjee, Avijit; Grabbe, Shon; Sridhar, Banavar

    2011-01-01

    Delays caused by uncertainty in weather forecasts can be reduced by improving traffic flow management decisions. This paper presents a methodology for traffic flow management under uncertainty in convective weather forecasts. An algorithm for assigning departure delays and reroutes to aircraft is presented. Departure delay and route assignment are executed at multiple stages, during which, updated weather forecasts and flight schedules are used. At each stage, weather forecasts up to a certain look-ahead time are treated as deterministic and flight scheduling is done to mitigate the impact of weather on four-dimensional flight trajectories. Uncertainty in weather forecasts during departure scheduling results in tactical airborne holding of flights. The amount of airborne holding depends on the accuracy of forecasts as well as the look-ahead time included in the departure scheduling. The weather forecast look-ahead time is varied systematically within the experiments performed in this paper to analyze its effect on flight delays. Based on the results, longer look-ahead times cause higher departure delays and additional flying time due to reroutes. However, the amount of airborne holding necessary to prevent weather incursions reduces when the forecast look-ahead times are higher. For the chosen day of traffic and weather, setting the look-ahead time to 90 minutes yields the lowest total delay cost.

  10. Gradual and abrupt changes during the Mid-Pleistocene Transition

    NASA Astrophysics Data System (ADS)

    Ford, Heather L.; Sosdian, Sindia M.; Rosenthal, Yair; Raymo, Maureen E.

    2016-09-01

    During the Mid-Pleistocene Transition (MPT), the dominant glacial-interglacial cyclicity as inferred from the marine δ18O records of benthic foraminifera (δ18Obenthic) changed from 41 kyr to 100 kyr years in the absence of a comparable change in orbital forcing. Currently, only two Mg/Ca-derived, high-resolution bottom water temperature (BWT) records exist that can be used with δ18Obenthic records to separate temperature and ice volume signals over the Pleistocene. However, these two BWT records suggest a different pattern of climate change occurred over the MPT-a record from North Atlantic DSDP Site 607 suggests BWT decreased with no long-term trend in ice volume over the MPT, while South Pacific ODP Site 1123 suggests that BWT has been relatively stable over the last 1.5 Myr but that there was an abrupt increase in ice volume at ∼900 kyr. In this paper we attempt to reconcile these two views of climate change across the MPT. Specifically, we investigated the suggestion that the secular BWT trend obtained from Mg/Ca measurements on Cibicidoides wuellerstorfi and Oridorsalis umbonatus species from N. Atlantic Site 607 is biased by the possible influence of Δ[CO32-] on Mg/Ca values in these species by generating a low-resolution BWT record using Uvigerina spp., a genus whose Mg/Ca values are not thought to be influenced by Δ[CO32-]. We find a long-term BWT cooling of ∼2-3°C occurred from 1500 to ∼500 kyr in the N. Atlantic, consistent with the previously generated C. wuellerstorfi and O. umbonatus BWT record. We also find that changes in ocean circulation likely influenced δ18Obenthic, BWT, and δ18Oseawater records across the MPT. N. Atlantic BWT cooling starting at ∼1.2 Ma, presumably driven by high-latitude cooling, may have been a necessary precursor to a threshold response in climate-ice sheet behavior at ∼900 ka. At that point, a modest increase in ice volume and thermohaline reorganization may have caused enhanced sensitivity to the 100 kyr

  11. Arctic Ocean freshwater as a trigger for abrupt climate change

    NASA Astrophysics Data System (ADS)

    Bradley, Raymond; Condron, Alan; Coletti, Anthony

    2016-04-01

    The cause of the Younger Dryas cooling remains unresolved despite decades of debate. Current arguments focus on either freshwater from Glacial Lake Agassiz drainage through the St Lawrence or the MacKenzie river systems. High resolution ocean modeling suggests that freshwater delivered to the North Atlantic from the Arctic Ocean through Fram Strait would have had more of an impact on Atlantic Meridional Overturning Circulation (AMOC) than freshwater from the St Lawrence. This has been interpreted as an argument for a MacKenzie River /Lake Agassiz freshwater source. However, it is important to note that although the modeling identifies Fram Strait as the optimum location for delivery of freshwater to disrupt the AMOC, this does not mean the freshwater source came from Lake Agassiz. Another potential source of freshwater is the Arctic Ocean ice cover itself. During the LGM, ice cover was extremely thick - many tens of meters in the Canada Basin (at least), resulting in a hiatus in sediment deposition there. Extreme ice thickness was related to a stagnant circulation, very low temperatures and continuous accumulation of snow on top of a base of sea-ice. This resulted in a large accumulation of freshwater in the Arctic Basin. As sea-level rose and a more modern circulation regime became established in the Arctic, this freshwater was released from the Arctic Ocean through Fram Strait, leading to extensive sea-ice formation in the North Atlantic (Greenland Sea) and a major reduction in the AMOC. Here we present new model results and a review of the paleoceanographic evidence to support this hypothesis. The bottom line is that the Arctic Ocean was likely a major player in causing abrupt climate change in the past, via its influence on the AMOC. Although we focus here on the Younger Dryas, the Arctic Ocean has been repeatedly isolated from the world ocean during glacial periods of the past. When these periods of isolation ended, it is probable that there were significant

  12. Response of dominant wind wave fields to abrupt wind increase

    NASA Astrophysics Data System (ADS)

    Caulliez, Guillemette

    2013-04-01

    Over the last decades, significant progress has been made in modelling wave field development by wind observed at sea, based on more elaborated numerical schemes and refined parametrizations of wind energy input and wave dissipation. In such models, the wind wave growth in space or time is generally governed by the average wind speed evaluated at one reference level and the natural wind speed variability is neglected. However, the impact of this assumption is not really known, mainly because of the lack of appropriate observations. To revisit this question, we report a detailed laboratory investigation aimed at describing the dominant wave field evolution resulting from an abrupt local wind speed increase. The experiments were conducted in the large Marseille-Luminy wind wave tank for moderate to high wind conditions. At 23 m fetch, a contraction of the wind tunnel section by a convergent profile created a spatial wind speed acceleration over a distance of about 2 m. Downwind, the wind speed, enhanced by a factor 1.4, was kept constant up to the end of the water tank. The wind wave field development induced by such a "wind gust" was investigated at successive fetches by wave probes and compared to those observed at similar fetches for homogeneous wind conditions. When wind increases, these observations first revealed no dramatic change in the evolution of the dominant spectral peak with fetch. The dominant wave energy which increases slowly for constant wind conditions, follows the wind speed but with a significant space lag. For well-established gravity wave fields, the space relaxation scales which describe this evolution do not depend noticeably on wind, all the curves collapse into a single one when wave quantities are normalized by their value observed just upstream the convergent profile. The wave growth rate observed for the new equilibrium state can be described by the Hasselman et al. (1973) relationship but with an "equivalent'' shorter fetch since, in

  13. Investigation and experimental analysis of the bubble departure diameter in pure liquids on horizontal cylindrical heater

    NASA Astrophysics Data System (ADS)

    Bovard, Samaneh; Asadinia, Hoda; Hosseini, Goharshad; Alavi Fazel, S. A.

    2016-08-01

    In this study, partial pool boiling heat transfer and bubble departure diameter on horizontal cylindrical heater in heat flux range between 103 and 105 w m-2 were investigated. Pure liquid water, Ethanol and Acetone were utilized as the fluids for the system. Aluminum, stainless steel 316A, copper and brass were considered as the materials for the heater's surface rod. Different degrees of roughness were applied for copper and aluminum surface. Bubble departure diameter and heat transfer coefficients were chosen for the system measurement. The empirical model for bubble departure diameter was estimated by using experimental data. This model is based on dimensionless numbers that through which experimental data are shown from literature and the present the study is in good agreement with the model.

  14. Precision Departure Release Capability (PDRC) Overview and Results: NASA to FAA Research Transition

    NASA Technical Reports Server (NTRS)

    Engelland, Shawn; Davis, Tom.

    2013-01-01

    NASA researchers developed the Precision Departure Release Capability (PDRC) concept to improve the tactical departure scheduling process. The PDRC system is comprised of: 1) a surface automation system that computes ready time predictions and departure runway assignments, 2) an en route scheduling automation tool that uses this information to estimate ascent trajectories to the merge point and computes release times and, 3) an interface that provides two-way communication between the two systems. To minimize technology transfer issues and facilitate its adoption by TMCs and Frontline Managers (FLM), NASA developed the PDRC prototype using the Surface Decision Support System (SDSS) for the Tower surface automation tool, a research version of the FAA TMA (RTMA) for en route automation tool and a digital interface between the two DSTs to facilitate coordination.

  15. Extracting Message Inter-Departure Time Distributions from the Human Electroencephalogram

    PubMed Central

    Mišić, Bratislav; Vakorin, Vasily A.; Kovačević, Nataša; Paus, Tomáš; McIntosh, Anthony R.

    2011-01-01

    The complex connectivity of the cerebral cortex is a topic of much study, yet the link between structure and function is still unclear. The processing capacity and throughput of information at individual brain regions remains an open question and one that could potentially bridge these two aspects of neural organization. The rate at which information is emitted from different nodes in the network and how this output process changes under different external conditions are general questions that are not unique to neuroscience, but are of interest in multiple classes of telecommunication networks. In the present study we show how some of these questions may be addressed using tools from telecommunications research. An important system statistic for modeling and performance evaluation of distributed communication systems is the time between successive departures of units of information at each node in the network. We describe a method to extract and fully characterize the distribution of such inter-departure times from the resting-state electroencephalogram (EEG). We show that inter-departure times are well fitted by the two-parameter Gamma distribution. Moreover, they are not spatially or neurophysiologically trivial and instead are regionally specific and sensitive to the presence of sensory input. In both the eyes-closed and eyes-open conditions, inter-departure time distributions were more dispersed over posterior parietal channels, close to regions which are known to have the most dense structural connectivity. The biggest differences between the two conditions were observed at occipital sites, where inter-departure times were significantly more variable in the eyes-open condition. Together, these results suggest that message departure times are indicative of network traffic and capture a novel facet of neural activity. PMID:21673866

  16. Identifying Key Issues and Potential Solutions for Integrated Arrival, Departure, Surface Operations by Surveying Stakeholder Preferences

    NASA Technical Reports Server (NTRS)

    Aponso, Bimal; Coppenbarger, Richard A.; Jung, Yoon; Quon, Leighton; Lohr, Gary; O’Connor, Neil; Engelland, Shawn

    2015-01-01

    NASA's Aeronautics Research Mission Directorate (ARMD) collaborates with the FAA and industry to provide concepts and technologies that enhance the transition to the next-generation air-traffic management system (NextGen). To facilitate this collaboration, ARMD has a series of Airspace Technology Demonstration (ATD) sub-projects that develop, demonstrate, and transitions NASA technologies and concepts for implementation in the National Airspace System (NAS). The second of these sub-projects, ATD-2, is focused on the potential benefits to NAS stakeholders of integrated arrival, departure, surface (IADS) operations. To determine the project objectives and assess the benefits of a potential solution, NASA surveyed NAS stakeholders to understand the existing issues in arrival, departure, and surface operations, and the perceived benefits of better integrating these operations. NASA surveyed a broad cross-section of stakeholders representing the airlines, airports, air-navigation service providers, and industry providers of NAS tools. The survey indicated that improving the predictability of flight times (schedules) could improve efficiency in arrival, departure, and surface operations. Stakeholders also mentioned the need for better strategic and tactical information on traffic constraints as well as better information sharing and a coupled collaborative planning process that allows stakeholders to coordinate IADS operations. To assess the impact of a potential solution, NASA sketched an initial departure scheduling concept and assessed its viability by surveying a select group of stakeholders for a second time. The objective of the departure scheduler was to enable flights to move continuously from gate to cruise with minimal interruption in a busy metroplex airspace environment using strategic and tactical scheduling enhanced by collaborative planning between airlines and service providers. The stakeholders agreed that this departure concept could improve schedule

  17. Cryogenic Propellant Storage and Transfer Technology Demonstration: Prephase A Government Point-of-Departure Concept Study

    NASA Technical Reports Server (NTRS)

    Mulqueen, J. A.; Addona, B. M.; Gwaltney, D. A.; Holt, K. A.; Hopkins, R. C.; Matis, J. A.; McRight, P. S.; Popp, C. G.; Sutherlin, S. G.; Thomas, H. D.; Baysinger, M. F.; Maples, C. D.; Capizzo, P. D.; Fabisinski, L. L.; Hornsby, L. S.; Percy, T. K.; Thomas, S. D.

    2012-01-01

    The primary purpose of this study was to define a point-of-departure prephase A mission concept for the cryogenic propellant storage and transfer technology demonstration mission to be conducted by the NASA Office of the Chief Technologist (OCT). The mission concept includes identification of the cryogenic propellant management technologies to be demonstrated, definition of a representative mission timeline, and definition of a viable flight system design concept. The resulting mission concept will serve as a point of departure for evaluating alternative mission concepts and synthesizing the results of industry- defined mission concepts developed under the OCT contracted studies

  18. Launch window analysis in a new perspective with examples of departures from Earth to Mars

    NASA Technical Reports Server (NTRS)

    Thibodeau, J. R., III; Bond, V. R.

    1972-01-01

    Earth-departure windows are investigated for two round trip stopover missions to Mars. These are the 1981 inbound Venus swingby mission and the 1986 direct minimum-energy mission. The secular effects of planetary oblateness are used to predict the motion of the parking orbit. A procedure is developed for matching the motion of the parking orbit and the escape asymptote. Earth-departure velocity penalties, caused by orbital plane misalinement, are reduced by synchronizing the motion of the parking orbit and the escape trajectory.

  19. Control-system techniques for improved departure/spin resistance for fighter aircraft

    NASA Technical Reports Server (NTRS)

    Nguyen, L. T.; Gilbert, W. P.; Ogburn, M. E.

    1980-01-01

    Some fundamental information on control system effects on controllability of highly maneuverable aircraft at high angles of attack are summarized as well as techniques for enhancing fighter aircraft departure/spin resistance using control system design. The discussion includes: (1) a brief review of pertinent high angle of attack phenomena including aerodynamics, inertia coupling, and kinematic coupling; (2) effects of conventional stability augmentation systems at high angles of attack; (3) high angle of attack control system concepts designed to enhance departure/spin resistance; and (4) the outlook for applications of these concepts to future fighters, particularly those designs which incorporate relaxed static stability.

  20. Abrupt vegetation transitions characterise long-term Amazonian peatland development

    NASA Astrophysics Data System (ADS)

    Roucoux, K. H.; Baker, T. R.; Gosling, W. D.; Honorio Coronado, E.; Jones, T. D.; Lahteenoja, O.; Lawson, I. T.

    2012-04-01

    woodland with abundant Myrtaceae; (4) Expansion of Mauritia/Mauritiella palm swamp vegetation c. 1000 years ago representing establishment of the present day vegetation community. Our results show that the vegetation at this site has undergone continuous change throughout the period of peat formation. The sequence of vegetation development is not straightforward, being characterised by abrupt transitions between vegetation types and reversals in the apparent trajectory of change. Overall this suggests that the system is highly dynamic on centennial to millennial timescales. This complexity may reflect vegetation responses to a combination of external (physical) and internal (biological) drivers and the presence of thresholds in the system. Future investigations will work towards understanding the processes that drive these vegetation transitions and predicting peatland vegetation responses to future climatic change.

  1. Presidential Address: Turbulent magnetic fields in the Sun

    NASA Astrophysics Data System (ADS)

    Weiss, Nigel

    2001-06-01

    Nigel Weiss recounts his Presidential Address 2001, given to the RAS A&G Ordinary Meeting on 9 February 2001. Recent high-resolution observations, from the ground and from space, have revealed the fine structure of magnetic features at the surface of the Sun. At the same time, advances in computing power have at last made it possible to develop models of turbulent magnetoconvection that can be related to these observations. The key features of flux emergence and annihilation, as observed by the MDI experiment on SOHO, are reproduced in kinematic calculations, while three-dimensional numerical experiments reveal the dynamical processes that are involved. The pattern of convection depends on the strength of the magnetic field: as the mean field decreases, slender rising plumes give way to a regime where magnetic flux is separated from the motion and then to one where locally intense magnetic fields nestle between broad and vigorously convecting plumes. Moreover, turbulent convection is itself able to act as a small-scale dynamo, generating disordered fields near the solar surface.

  2. Probabilistic Polling And Voting In The 2008 Presidential Election

    PubMed Central

    Delavande, Adeline; Manski, Charles F.

    2010-01-01

    This article reports new empirical evidence on probabilistic polling, which asks persons to state in percent-chance terms the likelihood that they will vote and for whom. Before the 2008 presidential election, seven waves of probabilistic questions were administered biweekly to participants in the American Life Panel (ALP). Actual voting behavior was reported after the election. We find that responses to the verbal and probabilistic questions are well-aligned ordinally. Moreover, the probabilistic responses predict voting behavior beyond what is possible using verbal responses alone. The probabilistic responses have more predictive power in early August, and the verbal responses have more power in late October. However, throughout the sample period, one can predict voting behavior better using both types of responses than either one alone. Studying the longitudinal pattern of responses, we segment respondents into those who are consistently pro-Obama, consistently anti-Obama, and undecided/vacillators. Membership in the consistently pro- or anti-Obama group is an almost perfect predictor of actual voting behavior, while the undecided/vacillators group has more nuanced voting behavior. We find that treating the ALP as a panel improves predictive power: current and previous polling responses together provide more predictive power than do current responses alone. PMID:24683275

  3. The 2012 AANS Presidential Address. We are neurosurgery.

    PubMed

    McCormick, Paul C

    2012-12-01

    The theme of the 80th Annual Meeting of the American Association of Neurological Surgeons and the title of this presidential address, "We are neurosurgery," is a simple 3-word affirmation of who neurosurgeons are, what they have achieved, and how much there is yet to accomplish. Recent advances in neurobiology and the clinical neurosciences have brought an unprecedented understanding of the human nervous system in both health and disease. As a specialty, neurosurgery has translated knowledge, expanded techniques, and incorporated technology to exponentially expand the science and scope of neurosurgical practice. However, the rapidly advancing, divergently evolving growth of neurosurgery has had profound effects on all aspects of neurosurgery. In this address, the author examines the contemporary meaning of the annual meeting's theme as it relates to the science, practice, specialty, and profession of neurosurgery, as well as the neurosurgeon. In doing so, the author reveals his interpretation of "We are neurosurgery," which he hopes will have an effect on others. PMID:23198859

  4. The applicability of research on moving cut data-approximate entropy on abrupt climate change detection

    NASA Astrophysics Data System (ADS)

    Jin, Hongmei; He, Wenping; Liu, Qunqun; Wang, Jinsong; Feng, Guolin

    2016-04-01

    In this study, the performance of moving cut data-approximate entropy (MC-ApEn) to detect abrupt dynamic changes was investigated. Numerical tests in a time series model indicate that the MC-ApEn method is suitable for the detection of abrupt dynamic changes for three types of meteorological data: daily maximum temperature, daily minimum temperature, and daily precipitation. Additionally, the MC-ApEn method was used to detect abrupt climate changes in daily precipitation data from Northwest China and the Pacific Decadal Oscillation (PDO) index. The results show an abrupt dynamic change in precipitation in 1980 and in the PDO index in 1976. The times indicated for the abrupt changes are identical to those from previous results. Application of the analysis to observational data further confirmed the performance of the MC-ApEn method. Moreover, MC-ApEn outperformed the moving t test (MTT) and the moving detrended fluctuation analysis (MDFA) methods for the detection of abrupt dynamic changes in a simulated 1000-point daily precipitation dataset.

  5. 30 CFR 285.103 - When may MMS prescribe or approve departures from these regulations?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When may MMS prescribe or approve departures from these regulations? 285.103 Section 285.103 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE RENEWABLE ENERGY ALTERNATE USES OF EXISTING FACILITIES ON THE...

  6. 75 FR 32655 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-09

    ... 14 CFR Part 97 Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure.... SUMMARY: This rule establishes, amends, suspends, or revokes Standard Instrument Approach Procedures... and ODP copies may be obtained from: 1. FAA Public Inquiry Center (APA-200), FAA Headquarters...

  7. 76 FR 64006 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-17

    ... Federal Aviation Administration 14 CFR Part 97 Standard Instrument Approach Procedures, and Takeoff... Standard Instrument Approach Procedures (SIAPs) and associated Takeoff Minimums and Obstacle Departure..., individual SIAP and Takeoff Minimums and ODP copies may be obtained from: 1. FAA Public Inquiry Center...

  8. 75 FR 42310 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-21

    ... Federal Aviation Administration 14 CFR Part 97 Standard Instrument Approach Procedures, and Takeoff... Standard Instrument Approach Procedures (SIAPs) and associated Takeoff Minimums and Obstacle Departure..., individual SIAP and Takeoff Minimums and ODP copies may be obtained from: 1. FAA Public Inquiry Center...

  9. 30 CFR 585.103 - When may BOEM prescribe or approve departures from these regulations?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false When may BOEM prescribe or approve departures from these regulations? 585.103 Section 585.103 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE RENEWABLE ENERGY AND ALTERNATE USES OF EXISTING FACILITIES ON THE...

  10. Simulating the Longitudinal Effects of Changes in Financial Aid on Student Departure from College.

    ERIC Educational Resources Information Center

    DesJardins, Stephen L.; Ahlburg, Dennis A.; McCall, Brian P.

    2002-01-01

    Estimates from a hazard model of college student departure for 3,975 students simulated how financial aid changes affect withdrawal decisions. Changing loans to scholarships has a large impact and front-loading aid (giving gift aid for the first 2 years) a modest impact on retention. Financial aid may represent more to students than its dollar…

  11. Studying the Timing of Student Departure from College. AIR 2000 Annual Forum Paper.

    ERIC Educational Resources Information Center

    DesJardins, Stephen L.; Moye, Melinda J.

    This study describes the use of event history modeling as a tool for understanding student departure from college. Using data from the National Center for Education Statistics High School and Beyond (HS&B)/Sophomore Cohort longitudinal study a detailed history of individual students' college careers was constructed using a regression-like…

  12. 75 FR 13293 - Agency Information Collection Activities: Arrival and Departure Record

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-19

    ... (Nonimmigrant Visa Waiver Arrival/Departure), and the Electronic System for Travel Authorization (ESTA). This is... previously published in the Federal Register (74 FR 64092) on December 7, 2009, allowing for a 60- day.... This process is conducted in accordance with 5 CFR 1320.10. ] DATES: Written comments should...

  13. Why Principals Leave: Risk Factors for Premature Departure in the Netherlands Compared for Women and Men

    ERIC Educational Resources Information Center

    Kruger, M. L.; van Eck, E.; Vermeulen, A.

    2005-01-01

    The shortage of school leaders, mainly caused by the growing complexity of the job is steadily growing in recent years. This study reports on the results of a comparative empirical study into the causes of premature departure for male and female principals in primary and secondary education. Principals who have experienced premature departure…

  14. Testing for departures from additivity in mixtures of perfluoroalkyl acids (PFAAs)

    EPA Science Inventory

    This study is a follow-up to a paper by Carr, et al. that determined a design structure to optimally test for departures from additivity in a fixed ratio mixture of four perfluoroalkyl acids (PFAAs) using an in vitro transiently-transfected COS- 1 PPARa reporter model with an NHA...

  15. 8 CFR 264.6 - Application for a nonimmigrant arrival-departure record.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... REGULATIONS REGISTRATION AND FINGERPRINTING OF ALIENS IN THE UNITED STATES § 264.6 Application for a...-departure record by applying on the form designated by USCIS with the fee prescribed in 8 CFR 103.7(b)(1) and in accordance with the form instructions. (c) Processing. A pending application filed...

  16. 8 CFR 264.6 - Application for a nonimmigrant arrival-departure record.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... REGULATIONS REGISTRATION AND FINGERPRINTING OF ALIENS IN THE UNITED STATES § 264.6 Application for a...-departure record by applying on the form designated by USCIS with the fee prescribed in 8 CFR 103.7(b)(1) and in accordance with the form instructions. (c) Processing. A pending application filed...

  17. 8 CFR 264.6 - Application for a nonimmigrant arrival-departure record.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... REGULATIONS REGISTRATION AND FINGERPRINTING OF ALIENS IN THE UNITED STATES § 264.6 Application for a...-departure record by applying on the form designated by USCIS with the fee prescribed in 8 CFR 103.7(b)(1) and in accordance with the form instructions. (c) Processing. A pending application filed...

  18. 8 CFR 1240.26 - Voluntary departure-authority of the Executive Office for Immigration Review.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... period allowed means that the alternate order of removal takes effect immediately pursuant to 8 CFR 1241.1(f), except that an alien granted the privilege of voluntary departure under 8 CFR 1240.26(c) will... under 8 CFR 1240.26(c) will not be deemed to have departed under an order of removal if the...

  19. 8 CFR 1240.26 - Voluntary departure-authority of the Executive Office for Immigration Review.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... period allowed means that the alternate order of removal takes effect immediately pursuant to 8 CFR 1241.1(f), except that an alien granted the privilege of voluntary departure under 8 CFR 1240.26(c) will... under 8 CFR 1240.26(c) will not be deemed to have departed under an order of removal if the...

  20. 8 CFR 1240.26 - Voluntary departure-authority of the Executive Office for Immigration Review.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... period allowed means that the alternate order of removal takes effect immediately pursuant to 8 CFR 1241.1(f), except that an alien granted the privilege of voluntary departure under 8 CFR 1240.26(c) will... under 8 CFR 1240.26(c) will not be deemed to have departed under an order of removal if the...

  1. 8 CFR 1240.26 - Voluntary departure-authority of the Executive Office for Immigration Review.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... period allowed means that the alternate order of removal takes effect immediately pursuant to 8 CFR 1241.1(f), except that an alien granted the privilege of voluntary departure under 8 CFR 1240.26(c) will... under 8 CFR 1240.26(c) will not be deemed to have departed under an order of removal if the...

  2. 8 CFR 1240.26 - Voluntary departure-authority of the Executive Office for Immigration Review.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... period allowed means that the alternate order of removal takes effect immediately pursuant to 8 CFR 1241.1(f), except that an alien granted the privilege of voluntary departure under 8 CFR 1240.26(c) will... under 8 CFR 1240.26(c) will not be deemed to have departed under an order of removal if the...

  3. 49 CFR Appendix D to Part 215 - Pre-departure Inspection Procedure

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Pt. 215, App. D Appendix D to Part 215—Pre-departure Inspection Procedure At each location where a freight car is placed in a train and a person designated under § 215.11 is not on duty for the purpose of inspecting freight cars,...

  4. 49 CFR Appendix D to Part 215 - Pre-departure Inspection Procedure

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Pt. 215, App. D Appendix D to Part 215—Pre-departure Inspection Procedure At each location where a freight car is placed in a train and a person designated under § 215.11 is not on duty for the purpose of inspecting freight cars,...

  5. 49 CFR Appendix D to Part 215 - Pre-departure Inspection Procedure

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Pt. 215, App. D Appendix D to Part 215—Pre-departure Inspection Procedure At each location where a freight car is placed in a train and a person designated under § 215.11 is not on duty for the purpose of inspecting freight cars,...

  6. 49 CFR Appendix D to Part 215 - Pre-departure Inspection Procedure

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Pt. 215, App. D Appendix D to Part 215—Pre-departure Inspection Procedure At each location where a freight car is placed in a train and a person designated under § 215.11 is not on duty for the purpose of inspecting freight cars,...

  7. 49 CFR Appendix D to Part 215 - Pre-departure Inspection Procedure

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Pt. 215, App. D Appendix D to Part 215—Pre-departure Inspection Procedure At each location where a freight car is placed in a train and a person designated under § 215.11 is not on duty for the purpose of inspecting freight cars,...

  8. College Departure: Exploring Student Aid Effects on Multiple Mobility Patterns from Four-Year Institutions

    ERIC Educational Resources Information Center

    Kim, Dongbin; Saatcioglu, Argun; Neufeld, Amy

    2012-01-01

    College departure involves multiple mobility patterns that include lateral transfer (from a four-year to another four-year institution), reverse transfer (from a four-year to a two-year institution), and stop out (taking time out of higher education altogether). This study addresses how financial aid influences the likelihood of such mobility…

  9. 30 CFR 585.103 - When may BOEM prescribe or approve departures from these regulations?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false When may BOEM prescribe or approve departures from these regulations? 585.103 Section 585.103 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... natural resources; (3) Protect life (including human and wildlife), property, or the marine, coastal,...

  10. 19 CFR 4.81 - Reports of arrivals and departures in coastwise trade.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Reports of arrivals and departures in coastwise trade. 4.81 Section 4.81 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY VESSELS IN FOREIGN AND DOMESTIC TRADES Coastwise Procedure §...

  11. Involuntary Departure of Public School Principals in the State of Texas

    ERIC Educational Resources Information Center

    Davila, Elva Jimenez

    2010-01-01

    Few studies have examined the reasons for ineffective public school leadership. The study examined the factors associated with the involuntary departure of public school principals in the state of Texas and aimed to reveal the ineffective behaviors that erode the public school principal's leadership. The study also indirectly pointed out to…

  12. Career Mobility and Departure Intentions among School Principals in the United States: Incentives and Disincentives

    ERIC Educational Resources Information Center

    Tekleselassie, Abebayehu Aemero; Villarreal, Pedro, III

    2011-01-01

    Despite concerns about turnover among administrators, conditions that influence career longevity intentions of school principals are less known. To address this gap in the literature, we conducted a three-level Generalized Multilevel Model to estimate variations in school and district characteristics impacting principals' career departure and…

  13. 76 FR 5058 - Airports of Entry or Departure for Flights to and From Cuba

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-28

    ... or Departure for Flights to and From Cuba AGENCY: U.S. Customs and Border Protection, DHS. ACTION... United States and Cuba must arrive at or depart from one of three named U.S. airports: John F. Kennedy... the United States and Cuba. These amendments are in accordance with the President's recent...

  14. Examining the Influences on Faculty Departure Intentions: A Comparison of Tenured Versus Nontenured Faculty at Research Universities Using NSOPF-99

    ERIC Educational Resources Information Center

    Zhou, Ying; Volkwein, James Fredericks

    2004-01-01

    This empirical research examines the predictors of intended departure for tenured vs. nontenured full-time faculty at research and doctoral institutions across an array of disciplines. What are the characteristics of those who intend to leave their institutions? Do tenured and nontenured faculty show different patterns of intended departure? And…

  15. 76 FR 44349 - Agency Information Collection Activities: Arrival and Departure Record (Forms I-94 and I-94W) and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-25

    ... SECURITY U.S. Customs and Border Protection Agency Information Collection Activities: Arrival and Departure Record (Forms I-94 and I-94W) and Electronic System for Travel Authorization AGENCY: U.S. Customs and... Arrival/Departure), and the Electronic System for Travel Authorization (ESTA). CBP is proposing that...

  16. 75 FR 76997 - Agency Information Collection Activities: Arrival and Departure Record (Forms I-94 and I-94W) and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-10

    ... SECURITY U.S. Customs and Border Protection Agency Information Collection Activities: Arrival and Departure Record (Forms I-94 and I-94W) and Electronic System for Travel Authorization AGENCY: U.S. Customs and... Arrival/Departure), and the Electronic System for Travel Authorization (ESTA). This is a...

  17. 33 CFR 165.164 - Security Zones: Dignitary Arrival/Departure and United Nations Meetings, New York, NY.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .../Departure and United Nations Meetings, New York, NY. 165.164 Section 165.164 Navigation and Navigable Waters... Guard District § 165.164 Security Zones: Dignitary Arrival/Departure and United Nations Meetings, New... information broadcasts. (b) Regulations. (1) The general regulations contained in 33 CFR 165.33 apply. (2)...

  18. 8 CFR 1215.6 - Departure from the Canal Zone, the Trust Territory of the Pacific Islands, or outlying...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Departure from the Canal Zone, the Trust... CONTROLS OF ALIENS DEPARTING FROM THE UNITED STATES § 1215.6 Departure from the Canal Zone, the Trust... United States, any alien who seeks to depart from the Canal Zone, the Trust Territory of the...

  19. 22 CFR 46.6 - Departure from the Canal Zone, the Trust Territory of the Pacific Islands, or outlying...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Departure from the Canal Zone, the Trust... the Canal Zone, the Trust Territory of the Pacific Islands, or outlying possessions of the United... the departure of aliens from the United States, any alien who seeks to depart from the Canal Zone,...

  20. 8 CFR 215.6 - Departure from the Canal Zone, the Trust Territory of the Pacific Islands, or outlying...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Departure from the Canal Zone, the Trust... FROM THE UNITED STATES § 215.6 Departure from the Canal Zone, the Trust Territory of the Pacific... alien who seeks to depart from the Canal Zone, the Trust Territory of the Pacific Islands, or...

  1. Five Departures in Logic, Mathematics, and thus—Whether We Like It, or Not—in Physics as Well...

    NASA Astrophysics Data System (ADS)

    Rosinger, Elemér E.

    2015-07-01

    Physics depends on "physical intuition", much of which is formulated in terms of Mathematics. Mathematics itself depends on Logic. The paper presents three latest novelties in Logic which have major consequences in Mathematics. Further, it presents two possible significant departures in Mathematics itself. These five departures can have major implications in Physics. Some of them are indicated, among them in Quantum Mechanics and Relativity.

  2. 19 CFR 192.13 - Revocation of participants' AES post-departure (Option 4) filing privileges; appeal procedures.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Revocation of participants' AES post-departure... participants' AES post-departure (Option 4) filing privileges; appeal procedures. (a) Reasons for revocation... days of receipt of the notice of decision. Except as stated elsewhere in this paragraph, the...

  3. 30 CFR 250.432 - How do I obtain a departure to diverter design and installation requirements?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Diverter System Requirements § 250.432 How do I obtain a... departures, you must have discussed the departure in your APD and received approval from the District...

  4. 76 FR 28057 - Agency Information Collection Activities: Request for Entry or Departure for Flights To and From...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-13

    ... proposed information collection was previously published in the Federal Register (76 FR 13204) on March 10... Departure for Flights To and From Cuba AGENCY: U.S. Customs and Border Protection, Department of Homeland... Departure for Flights To and From Cuba. This is a proposed extension of an information collection that...

  5. Catalogue of abrupt shifts in Intergovernmental Panel on Climate Change climate models.

    PubMed

    Drijfhout, Sybren; Bathiany, Sebastian; Beaulieu, Claudie; Brovkin, Victor; Claussen, Martin; Huntingford, Chris; Scheffer, Marten; Sgubin, Giovanni; Swingedouw, Didier

    2015-10-27

    Abrupt transitions of regional climate in response to the gradual rise in atmospheric greenhouse gas concentrations are notoriously difficult to foresee. However, such events could be particularly challenging in view of the capacity required for society and ecosystems to adapt to them. We present, to our knowledge, the first systematic screening of the massive climate model ensemble informing the recent Intergovernmental Panel on Climate Change report, and reveal evidence of 37 forced regional abrupt changes in the ocean, sea ice, snow cover, permafrost, and terrestrial biosphere that arise after a certain global temperature increase. Eighteen out of 37 events occur for global warming levels of less than 2°, a threshold sometimes presented as a safe limit. Although most models predict one or more such events, any specific occurrence typically appears in only a few models. We find no compelling evidence for a general relation between the overall number of abrupt shifts and the level of global warming. However, we do note that abrupt changes in ocean circulation occur more often for moderate warming (less than 2°), whereas over land they occur more often for warming larger than 2°. Using a basic proportion test, however, we find that the number of abrupt shifts identified in Representative Concentration Pathway (RCP) 8.5 scenarios is significantly larger than in other scenarios of lower radiative forcing. This suggests the potential for a gradual trend of destabilization of the climate with respect to such shifts, due to increasing global mean temperature change. PMID:26460042

  6. Catalogue of abrupt shifts in Intergovernmental Panel on Climate Change climate models

    PubMed Central

    Drijfhout, Sybren; Bathiany, Sebastian; Beaulieu, Claudie; Brovkin, Victor; Claussen, Martin; Huntingford, Chris; Scheffer, Marten; Sgubin, Giovanni; Swingedouw, Didier

    2015-01-01

    Abrupt transitions of regional climate in response to the gradual rise in atmospheric greenhouse gas concentrations are notoriously difficult to foresee. However, such events could be particularly challenging in view of the capacity required for society and ecosystems to adapt to them. We present, to our knowledge, the first systematic screening of the massive climate model ensemble informing the recent Intergovernmental Panel on Climate Change report, and reveal evidence of 37 forced regional abrupt changes in the ocean, sea ice, snow cover, permafrost, and terrestrial biosphere that arise after a certain global temperature increase. Eighteen out of 37 events occur for global warming levels of less than 2°, a threshold sometimes presented as a safe limit. Although most models predict one or more such events, any specific occurrence typically appears in only a few models. We find no compelling evidence for a general relation between the overall number of abrupt shifts and the level of global warming. However, we do note that abrupt changes in ocean circulation occur more often for moderate warming (less than 2°), whereas over land they occur more often for warming larger than 2°. Using a basic proportion test, however, we find that the number of abrupt shifts identified in Representative Concentration Pathway (RCP) 8.5 scenarios is significantly larger than in other scenarios of lower radiative forcing. This suggests the potential for a gradual trend of destabilization of the climate with respect to such shifts, due to increasing global mean temperature change. PMID:26460042

  7. Catalogue of abrupt shifts in Intergovernmental Panel on Climate Change climate models.

    PubMed

    Drijfhout, Sybren; Bathiany, Sebastian; Beaulieu, Claudie; Brovkin, Victor; Claussen, Martin; Huntingford, Chris; Scheffer, Marten; Sgubin, Giovanni; Swingedouw, Didier

    2015-10-27

    Abrupt transitions of regional climate in response to the gradual rise in atmospheric greenhouse gas concentrations are notoriously difficult to foresee. However, such events could be particularly challenging in view of the capacity required for society and ecosystems to adapt to them. We present, to our knowledge, the first systematic screening of the massive climate model ensemble informing the recent Intergovernmental Panel on Climate Change report, and reveal evidence of 37 forced regional abrupt changes in the ocean, sea ice, snow cover, permafrost, and terrestrial biosphere that arise after a certain global temperature increase. Eighteen out of 37 events occur for global warming levels of less than 2°, a threshold sometimes presented as a safe limit. Although most models predict one or more such events, any specific occurrence typically appears in only a few models. We find no compelling evidence for a general relation between the overall number of abrupt shifts and the level of global warming. However, we do note that abrupt changes in ocean circulation occur more often for moderate warming (less than 2°), whereas over land they occur more often for warming larger than 2°. Using a basic proportion test, however, we find that the number of abrupt shifts identified in Representative Concentration Pathway (RCP) 8.5 scenarios is significantly larger than in other scenarios of lower radiative forcing. This suggests the potential for a gradual trend of destabilization of the climate with respect to such shifts, due to increasing global mean temperature change.

  8. Another issue comes out: gay rights policy voting in recent U.S. presidential elections.

    PubMed

    Rhodebeck, Laurie A

    2015-01-01

    Drawing from the theory of policy voting, this study examines the impact of opinions about gay rights on voting for presidential candidates. Qualitative analysis of the major party platforms and candidate campaign rhetoric from the six presidential elections held between 1988 and 2008 indicates that Democratic and Republican presidential candidates began openly expressing opposing positions on gay rights issues in 1992. Quantitative analysis of public opinion shows that, starting in 1992 and continuing through 2008, gay rights issues became more salient to the public, and opinions about gay rights began to exert a significant effect on vote choice. The study concludes with a discussion of the partisan forces that shaped the electoral significance of gay rights issues during the period from 1988 to 2008 and speculation about the role of gay rights issues in shaping future partisan electoral strategy.

  9. Another issue comes out: gay rights policy voting in recent U.S. presidential elections.

    PubMed

    Rhodebeck, Laurie A

    2015-01-01

    Drawing from the theory of policy voting, this study examines the impact of opinions about gay rights on voting for presidential candidates. Qualitative analysis of the major party platforms and candidate campaign rhetoric from the six presidential elections held between 1988 and 2008 indicates that Democratic and Republican presidential candidates began openly expressing opposing positions on gay rights issues in 1992. Quantitative analysis of public opinion shows that, starting in 1992 and continuing through 2008, gay rights issues became more salient to the public, and opinions about gay rights began to exert a significant effect on vote choice. The study concludes with a discussion of the partisan forces that shaped the electoral significance of gay rights issues during the period from 1988 to 2008 and speculation about the role of gay rights issues in shaping future partisan electoral strategy. PMID:25530286

  10. 77 FR 49789 - Record of Decision for Issuing a Presidential Permit to Energia Sierra Juarez U.S. Transmission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-17

    ... of Decision for Issuing a Presidential Permit to Energia Sierra Juarez U.S. Transmission, LLC, for the Energia Sierra Juarez U.S. Transmission Line Project AGENCY: Office of Electricity Delivery and... announces its decision to issue a Presidential permit to Energia Sierra Juarez U.S. Transmission, LLC...

  11. 36 CFR 1254.14 - Are some procedures in regional archives and Presidential libraries different from those in the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... regional archives and Presidential libraries different from those in the Washington, DC, area? 1254.14... procedures in regional archives and Presidential libraries different from those in the Washington, DC, area... to differences in some, but not all, practices from the Washington, DC, area. When the...

  12. 36 CFR 1254.14 - Are some procedures in regional archives and Presidential libraries different from those in the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... regional archives and Presidential libraries different from those in the Washington, DC, area? 1254.14... procedures in regional archives and Presidential libraries different from those in the Washington, DC, area... to differences in some, but not all, practices from the Washington, DC, area. When the...

  13. 3 CFR - Presidential Determination Under Section 402 (c)(2)(A) of the Trade Act of 1974-Republic of Belarus

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...)(A) of the Trade Act of 1974-Republic of Belarus Presidential Documents Other Presidential Documents...) of the Trade Act of 1974—Republic of Belarus Memorandum for the Secretary of State Pursuant to... with respect to Belarus will substantially promote the objectives of section 402. You are...

  14. Presidential Transitions: It's Not Just the Position, It's the Transition. ACE/Praeger Series on Higher Education

    ERIC Educational Resources Information Center

    Sanaghan, Patrick H.; Goldstein, Larry; Gaval, Kathleen D.

    2007-01-01

    A presidential transition has a major impact on the life of an institution. Hundreds of presidential transitions take place annually, and when they are not amicable and carefully orchestrated, they can scar both the institution and the president. This book is designed to provide assistance to presidents, trustees, faculty, and other important…

  15. 77 FR 72430 - Application for a Presidential Permit To Operate and Maintain Pipeline Facilities on the Border...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-05

    ... Application for a Presidential Permit To Operate and Maintain Pipeline Facilities on the Border of the United... Presidential Permit to Operate and Maintain Pipeline Facilities on the Border of the United States and Canada... at the U.S.- Canada border (St. Clair Pipeline border facilities). The pipeline facilities...

  16. 36 CFR 1281.8 - What information must be provided to NARA for its report to Congress on a new Presidential...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... provided to NARA for its report to Congress on a new Presidential library facility? 1281.8 Section 1281.8... PRESIDENTIAL LIBRARY FACILITIES § 1281.8 What information must be provided to NARA for its report to Congress on a new Presidential library facility? (a) NARA must submit a report to Congress on a proposed...

  17. 36 CFR 1281.8 - What information must be provided to NARA for its report to Congress on a new Presidential...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... provided to NARA for its report to Congress on a new Presidential library facility? 1281.8 Section 1281.8... PRESIDENTIAL LIBRARY FACILITIES § 1281.8 What information must be provided to NARA for its report to Congress on a new Presidential library facility? (a) NARA must submit a report to Congress on a proposed...

  18. 36 CFR 1281.8 - What information must be provided to NARA for its report to Congress on a new Presidential...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... provided to NARA for its report to Congress on a new Presidential library facility? 1281.8 Section 1281.8... PRESIDENTIAL LIBRARY FACILITIES § 1281.8 What information must be provided to NARA for its report to Congress on a new Presidential library facility? (a) NARA must submit a report to Congress on a proposed...

  19. 36 CFR 1281.8 - What information must be provided to NARA for its report to Congress on a new Presidential...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... provided to NARA for its report to Congress on a new Presidential library facility? 1281.8 Section 1281.8... PRESIDENTIAL LIBRARY FACILITIES § 1281.8 What information must be provided to NARA for its report to Congress on a new Presidential library facility? (a) NARA must submit a report to Congress on a proposed...

  20. Presidential addresses of the Royal Society of Tropical Medicine and Hygiene: 1907-2013.

    PubMed

    Hay, Simon I; McHugh, Gerri M

    2013-10-01

    Presidents have been required to give an inaugural address on commencing office at the Royal Society of Tropical Medicine and Hygiene (RSTMH) since its foundation in 1907. All presidential addresses were identified, sourced and assembled into an annotated bibliography. The majority of presidential addresses have been published in Transactions of the Royal Society of Tropical Medicine and Hygiene. Unpublished and in some cases 'lost' contributions have now been sourced where possible and archived at the RSTMH. This unique, rich and rewarding archive provides a vista into the development of the RSTMH and the discipline of tropical medicine. The archive is freely available to all.

  1. Presidential addresses of the Royal Society of Tropical Medicine and Hygiene: 1907–2013

    PubMed Central

    Hay, Simon I.; McHugh, Gerri M.

    2013-01-01

    Presidents have been required to give an inaugural address on commencing office at the Royal Society of Tropical Medicine and Hygiene (RSTMH) since its foundation in 1907. All presidential addresses were identified, sourced and assembled into an annotated bibliography. The majority of presidential addresses have been published in Transactions of the Royal Society of Tropical Medicine and Hygiene. Unpublished and in some cases ‘lost’ contributions have now been sourced where possible and archived at the RSTMH. This unique, rich and rewarding archive provides a vista into the development of the RSTMH and the discipline of tropical medicine. The archive is freely available to all. PMID:24026462

  2. Microscopic Approaches to Decomposition and Burning Processes of a Micro Plastic Resin Particle under Abrupt Heating

    NASA Astrophysics Data System (ADS)

    Ohiwa, Norio; Ishino, Yojiro; Yamamoto, Atsunori; Yamakita, Ryuji

    To elucidate the possibility and availability of thermal recycling of waste plastic resin from a basic and microscopic viewpoint, a series of abrupt heating processes of a spherical micro plastic particle having a diameter of about 200 μm is observed, when it is abruptly exposed to hot oxidizing combustion gas. Three ingenious devices are introduced and two typical plastic resins of polyethylene terephthalate and polyethylene are used. In this paper the dependency of internal and external appearances of residual plastic embers on the heating time and the ingredients of plastic resins is optically analyzed, along with appearances of internal micro bubbling, multiple micro explosions and jets, and micro diffusion flames during abrupt heating. Based on temporal variations of the surface area of a micro plastic particle, the apparent burning rate constant is also evaluated and compared with those of well-known volatile liquid fuels.

  3. Conclusive evidence of abrupt coagulation inside the void during cyclic nanoparticle formation in reactive plasma

    NASA Astrophysics Data System (ADS)

    van de Wetering, F. M. J. H.; Nijdam, S.; Beckers, J.

    2016-07-01

    In this letter, we present scanning electron microscopy (SEM) results that confirm in a direct way our earlier explanation of an abrupt coagulation event as the cause for the void hiccup. In a recent paper, we reported on the fast and interrupted expansion of voids in a reactive dusty argon-acetylene plasma. The voids appeared one after the other, each showing a peculiar, though reproducible, behavior of successive periods of fast expansion, abrupt contraction, and continued expansion. The abrupt contraction was termed "hiccup" and was related to collective coagulation of a new generation of nanoparticles growing in the void using relatively indirect methods: electron density measurements and optical emission spectroscopy. In this letter, we present conclusive evidence using SEM of particles collected at different moments in time spanning several growth cycles, which enables us to follow the nanoparticle formation process in great detail.

  4. Gradual onset and recovery of the Younger Dryas abrupt climate event in the tropics

    PubMed Central

    Partin, J.W.; Quinn, T.M.; Shen, C.-C.; Okumura, Y.; Cardenas, M.B.; Siringan, F.P.; Banner, J.L.; Lin, K.; Hu, H.-M.; Taylor, F.W.

    2015-01-01

    Proxy records of temperature from the Atlantic clearly show that the Younger Dryas was an abrupt climate change event during the last deglaciation, but records of hydroclimate are underutilized in defining the event. Here we combine a new hydroclimate record from Palawan, Philippines, in the tropical Pacific, with previously published records to highlight a difference between hydroclimate and temperature responses to the Younger Dryas. Although the onset and termination are synchronous across the records, tropical hydroclimate changes are more gradual (>100 years) than the abrupt (10–100 years) temperature changes in the northern Atlantic Ocean. The abrupt recovery of Greenland temperatures likely reflects changes in regional sea ice extent. Proxy data and transient climate model simulations support the hypothesis that freshwater forced a reduction in the Atlantic meridional overturning circulation, thereby causing the Younger Dryas. However, changes in ocean overturning may not produce the same effects globally as in Greenland. PMID:26329911

  5. Abrupt onset of tongue deformation and phase space response of ions in magnetically-confined plasmas

    PubMed Central

    Ida, K.; Kobayashi, T.; Itoh, K.; Yoshinuma, M.; Tokuzawa, T.; Akiyama, T.; Moon, C.; Tsuchiya, H.; Inagaki, S.; Itoh, S.-I.

    2016-01-01

    An abrupt onset of the new tongue-shaped deformation of magnetic surface in magnetized plasmas, which was conjectured in since the 1960s but has not been observed, is experimentally identified just before an abrupt onset of a large-scale collapse event. Two novel properties of the event are identified. First, the transition of symmetry of perturbation (rather than a growth of linearly unstable MHD modes) was found to be a key for the onset of abrupt collapse, i.e., the transition of symmetry gives a new route to the collapse from stable state. Second, as a phase-space response of ions, the distortion from Maxwell-Boltzmann distribution of epithermal ions was observed for the first time. PMID:27796370

  6. Novel insights into molecular mechanisms of abruption-induced preterm birth

    PubMed Central

    Buhimschi, Catalin S.; Schatz, Frederik; Krikun, Graciela; Buhimschi, Irina A.; Lockwood, Charles J.

    2015-01-01

    Preterm birth (PTB) complicates more than 12% of all deliveries. Despite significant research, the aetiology of most cases of PTB remains elusive. Two major antecedents of PTB, intra-amniotic infection and decidual haemorrhage (abruption), can exhibit dissimilar demographic and genetic predispositions, despite sharing common molecular and cellular pathways. The use of high-throughput, high-dimensional technologies reveals substantial crosstalk between the coagulation and inflammation pathways. Tissue factor, thrombin and cytokines are key mediators of this crosstalk. Abruptions are associated with excess thrombin generated from decidual-cell-expressed tissue factor. Although thrombin is a primary mediator of the coagulation cascade, it can also promote inflammation-associated PTB by enhancing expression of matrix metalloproteinase and neutrophil-chemoattracting and -activating chemokines. Here, we provide novel insights into the molecular mechanisms and pathways leading to PTB in the setting of placental abruption. PMID:21040617

  7. The Necessity of Awareness of Early Symptoms of Placental Abruption Among Pregnant Japanese Women

    PubMed Central

    Suzuki, Shunji; Shinmura, Hiroki

    2016-01-01

    Background In 2012, the recommendation for immediate contact and visit to obstetric institutions by pregnant women was emphasized by The Japan Obstetric Compensation System for Cerebral Palsy (JOCSC). In this study, we examined whether or not the increased awareness has led to the improvement of perinatal outcomes of placental abruption managed at private clinics. Methods We reviewed the obstetric records of 38 singleton pregnant women complicated by placental abruption that developed at home, and were managed at private clinics from April 2008 through April 2016. Results The perinatal outcomes, specifically the rate of cases with ≥ 1 hour time interval between symptom onset and clinic visit, have not changed significantly after the intervention. Conclusion The provision of information regarding the early clinical symptoms associated with placental abruption in pregnant women has not been well documented in Japan. PMID:27540442

  8. Gradual onset and recovery of the Younger Dryas abrupt climate event in the tropics

    NASA Astrophysics Data System (ADS)

    Partin, J. W.; Quinn, T. M.; Shen, C.-C.; Okumura, Y.; Cardenas, M. B.; Siringan, F. P.; Banner, J. L.; Lin, K.; Hu, H.-M.; Taylor, F. W.

    2015-09-01

    Proxy records of temperature from the Atlantic clearly show that the Younger Dryas was an abrupt climate change event during the last deglaciation, but records of hydroclimate are underutilized in defining the event. Here we combine a new hydroclimate record from Palawan, Philippines, in the tropical Pacific, with previously published records to highlight a difference between hydroclimate and temperature responses to the Younger Dryas. Although the onset and termination are synchronous across the records, tropical hydroclimate changes are more gradual (>100 years) than the abrupt (10-100 years) temperature changes in the northern Atlantic Ocean. The abrupt recovery of Greenland temperatures likely reflects changes in regional sea ice extent. Proxy data and transient climate model simulations support the hypothesis that freshwater forced a reduction in the Atlantic meridional overturning circulation, thereby causing the Younger Dryas. However, changes in ocean overturning may not produce the same effects globally as in Greenland.

  9. Abrupt climate change in southeast tropical Africa influenced by Indian monsoon variability and ITCZ migration

    NASA Astrophysics Data System (ADS)

    Tierney, Jessica E.; Russell, James M.

    2007-08-01

    The timing and magnitude of abrupt climate change in tropical Africa during the last glacial termination remains poorly understood. High-resolution paleolimnological data from Lake Tanganyika, Southeast Africa show that wind-driven seasonal mixing in the lake was reduced during the Younger Dryas, Inter-Allerød Cool Period, Older Dryas, and Heinrich Event 1, suggesting a weakened southwest Indian monsoon and a more southerly position of the Inter-Tropical Convergence Zone over Africa during these intervals. These events in Lake Tanganyika, coeval with millennial and centennial-scale climate shifts in the high latitudes, suggest that changes in ITCZ location and Indian monsoon strength are important components of abrupt global climate change and that their effects are felt south of the equator in Africa. However, we observe additional events in Lake Tanganyika of equal magnitude that are not correlated with high-latitude changes, indicating the potential for abrupt climate change to originate from within tropical systems.

  10. Abrupt change of Antarctic moisture origin at the end of Termination II.

    PubMed

    Masson-Delmotte, V; Stenni, B; Blunier, T; Cattani, O; Chappellaz, J; Cheng, H; Dreyfus, G; Edwards, R L; Falourd, S; Govin, A; Kawamura, K; Johnsen, S J; Jouzel, J; Landais, A; Lemieux-Dudon, B; Lourantou, A; Marshall, G; Minster, B; Mudelsee, M; Pol, K; Röthlisberger, R; Selmo, E; Waelbroeck, C

    2010-07-01

    The deuterium excess of polar ice cores documents past changes in evaporation conditions and moisture origin. New data obtained from the European Project for Ice Coring in Antarctica Dome C East Antarctic ice core provide new insights on the sequence of events involved in Termination II, the transition between the penultimate glacial and interglacial periods. This termination is marked by a north-south seesaw behavior, with first a slow methane concentration rise associated with a strong Antarctic temperature warming and a slow deuterium excess rise. This first step is followed by an abrupt north Atlantic warming, an abrupt resumption of the East Asian summer monsoon, a sharp methane rise, and a CO(2) overshoot, which coincide within dating uncertainties with the end of Antarctic optimum. Here, we show that this second phase is marked by a very sharp Dome C centennial deuterium excess rise, revealing abrupt reorganization of atmospheric circulation in the southern Indian Ocean sector.

  11. Gradual onset and recovery of the Younger Dryas abrupt climate event in the tropics.

    PubMed

    Partin, J W; Quinn, T M; Shen, C-C; Okumura, Y; Cardenas, M B; Siringan, F P; Banner, J L; Lin, K; Hu, H-M; Taylor, F W

    2015-09-02

    Proxy records of temperature from the Atlantic clearly show that the Younger Dryas was an abrupt climate change event during the last deglaciation, but records of hydroclimate are underutilized in defining the event. Here we combine a new hydroclimate record from Palawan, Philippines, in the tropical Pacific, with previously published records to highlight a difference between hydroclimate and temperature responses to the Younger Dryas. Although the onset and termination are synchronous across the records, tropical hydroclimate changes are more gradual (>100 years) than the abrupt (10-100 years) temperature changes in the northern Atlantic Ocean. The abrupt recovery of Greenland temperatures likely reflects changes in regional sea ice extent. Proxy data and transient climate model simulations support the hypothesis that freshwater forced a reduction in the Atlantic meridional overturning circulation, thereby causing the Younger Dryas. However, changes in ocean overturning may not produce the same effects globally as in Greenland.

  12. 41 CFR 301-11.10 - Am I required to record departure/arrival dates and times on my travel claim?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... departure/arrival dates and times on my travel claim? 301-11.10 Section 301-11.10 Public Contracts and... dates and times on my travel claim? You must record the date of departure from, and arrival at, the... visited. You do not have to record departure/arrival times, but you must annotate your travel claim...

  13. 41 CFR 301-11.10 - Am I required to record departure/arrival dates and times on my travel claim?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... departure/arrival dates and times on my travel claim? 301-11.10 Section 301-11.10 Public Contracts and... dates and times on my travel claim? You must record the date of departure from, and arrival at, the... visited. You do not have to record departure/arrival times, but you must annotate your travel claim...

  14. 41 CFR 301-11.10 - Am I required to record departure/arrival dates and times on my travel claim?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... departure/arrival dates and times on my travel claim? 301-11.10 Section 301-11.10 Public Contracts and... dates and times on my travel claim? You must record the date of departure from, and arrival at, the... visited. You do not have to record departure/arrival times, but you must annotate your travel claim...

  15. 41 CFR 301-11.10 - Am I required to record departure/arrival dates and times on my travel claim?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... departure/arrival dates and times on my travel claim? 301-11.10 Section 301-11.10 Public Contracts and... dates and times on my travel claim? You must record the date of departure from, and arrival at, the... visited. You do not have to record departure/arrival times, but you must annotate your travel claim...

  16. 41 CFR 301-11.10 - Am I required to record departure/arrival dates and times on my travel claim?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... departure/arrival dates and times on my travel claim? 301-11.10 Section 301-11.10 Public Contracts and... dates and times on my travel claim? You must record the date of departure from, and arrival at, the... visited. You do not have to record departure/arrival times, but you must annotate your travel claim...

  17. Myocardial infarction complicated by left ventricular thrombus and fatal thromboembolism following abrupt cessation of dabigatran.

    PubMed

    Weiler, Bethany; Marciniak, Ellen T; Reed, Robert M; McCurdy, Michael T

    2014-07-04

    Novel anticoagulants are increasingly utilised in lieu of warfarin to treat non-valvular atrial fibrillation. Their clinical use in other non-FDA approved settings is also increasing. We present a case in which a patient abruptly stopped taking dabigatran due to a small bowel obstruction and shortly thereafter suffered a myocardial infarction complicated by left ventricular thrombosis with fatal embolisation to the superior mesenteric artery. In this context, we discuss the possibility of a rebound phenomenon of hypercoagulability with abrupt cessation of novel anticoagulants.

  18. Phase-locked states and abrupt shifts in Pacific climate indices

    NASA Astrophysics Data System (ADS)

    Douglass, David H.

    2013-10-01

    Douglass has shown that ENSO index aNino3.4 contains segments phase locked to subharmonics of the annual solar cycle and also that a set of indices including aNino3.4 shows abrupt shifts between these phase-locked states. Here, four additional Pacific indices are studied. These five indices show that the Pacific climate system alternates between two regimes: (1) Solar cycle (SOL), (2) Teleconnections (TEL). During SOL each index shows two components that are phase locked to the solar cycle. The first is at the annual cycle, while the second is at a subharmonic of the annual cycle. During TEL abrupt climate shifts occur.

  19. New evidence from the South China Sea for an abrupt termination of the last glacial period

    NASA Technical Reports Server (NTRS)

    Broecker, W. S.; Klas, M.; Andree, M.; Bonani, G.; Wolfli, W.

    1988-01-01

    Results demonstrating an abrupt change in the rate and character of sedimentation in the South China Sea at the close of the last glacial period are presented. Radiocarbon dating and its position in the oxygen isotope shift suggest that this change may be coincident with the abrupt change in climatic conditions seen at high latitudes in the North Atlantic and the Antarctic at 13 kyr BP. These results support the contention that a major global climatic change occurred between 14 and 13 kyr BP.

  20. Large-scale circulation departures related to wet episodes in northeast Brazil

    NASA Technical Reports Server (NTRS)

    Sikdar, D. N.; Elsner, J. B.

    1985-01-01

    Large scale circulation features are presented as related to wet spells over northeast Brazil (Nordeste) during the rainy season (March and April) of 1979. The rainy season season is devided into dry and wet periods, the FGGE and geostationary satellite data was averaged and mean and departure fields of basic variables and cloudiness were studied. Analysis of seasonal mean circulation features show: lowest sea level easterlies beneath upper level westerlies; weak meridional winds; high relative humidity over the Amazon basin and relatively dry conditions over the South Atlantic Ocean. A fluctuation was found in the large scale circulation features on time scales of a few weeks or so over Nordeste and the South Atlantic sector. Even the subtropical High SLP's have large departures during wet episodes, implying a short period oscillation in the Southern Hemisphere Hadley circulation.

  1. Comprehensive Optimization of Emergency Evacuation Route and Departure Time under Traffic Control

    PubMed Central

    Zhou, Ying; Liu, Mengqi

    2014-01-01

    With the frequent occurrence of major emergencies, emergency management gets high attention from all around the world. This paper investigates the comprehensive optimization of major emergency evacuation route and departure time, in which case the evacuation propagation mechanism is considered under traffic control. Given the practical assumptions, we first establish a comprehensive optimization model based on the simulation of evacuation route and departure time. Furthermore, we explore the reasonable description method of evacuation traffic flow propagation under traffic control, including the establishment of traffic flow propagation model and the design of the simulation mudule that can simulate the evacuation traffic flow. Finally, we propose a heuristic algorithm for the optimization of this comprehensive model. In case analysis, we take some areas in Beijing as the evaluation sources to verify the reliability of our model. A series of constructive suggestions for Beijing's emergency evacuation are proposed, which can be applied to the actual situation under traffic control. PMID:24977232

  2. Scaling relation between earthquake magnitude and the departure time from P wave similar growth

    NASA Astrophysics Data System (ADS)

    Noda, Shunta; Ellsworth, William L.

    2016-09-01

    We introduce a new scaling relation between earthquake magnitude (M) and a characteristic of initial P wave displacement. By examining Japanese K-NET data averaged in bins partitioned by Mw and hypocentral distance, we demonstrate that the P wave displacement briefly displays similar growth at the onset of rupture and that the departure time (Tdp), which is defined as the time of departure from similarity of the absolute displacement after applying a band-pass filter, correlates with the final M in a range of 4.5 ≤ Mw ≤ 7. The scaling relation between Mw and Tdp implies that useful information on the final M can be derived while the event is still in progress because Tdp occurs before the completion of rupture. We conclude that the scaling relation is important not only for earthquake early warning but also for the source physics of earthquakes.

  3. Optimizing Flight Departure Delay and Route Selection Under En Route Convective Weather

    NASA Technical Reports Server (NTRS)

    Mukherjee, Avijit; Sridhar, Banavar; Grabbe, Shon

    2010-01-01

    This paper presents a linear Integer Programming model for managing air traffic flow in the United States. The decision variables in the model are departure delays and predeparture reroutes of aircraft whose trajectories are predicted to cross weather-impacted regions of the National Airspace System. The model assigns delays to a set of flights while ensuring their trajectories are free of any conflicts with weather. In a deterministic setting, there is no airborne holding due to unexpected weather incursion in a flight s path. The model is applied to solve a large-scale traffic flow management problem with realistic weather data and flight schedules. Experimental results indicate that allowing rerouting can reduce departure delays by nearly 57%, but it is associated with an increase in total airborne time due to longer routes flown by aircraft. The computation times to solve this problem were significantly lower than those reported in the earlier studies.

  4. Comprehensive optimization of emergency evacuation route and departure time under traffic control.

    PubMed

    Li, Guo; Zhou, Ying; Liu, Mengqi

    2014-01-01

    With the frequent occurrence of major emergencies, emergency management gets high attention from all around the world. This paper investigates the comprehensive optimization of major emergency evacuation route and departure time, in which case the evacuation propagation mechanism is considered under traffic control. Given the practical assumptions, we first establish a comprehensive optimization model based on the simulation of evacuation route and departure time. Furthermore, we explore the reasonable description method of evacuation traffic flow propagation under traffic control, including the establishment of traffic flow propagation model and the design of the simulation module that can simulate the evacuation traffic flow. Finally, we propose a heuristic algorithm for the optimization of this comprehensive model. In case analysis, we take some areas in Beijing as the evaluation sources to verify the reliability of our model. A series of constructive suggestions for Beijing's emergency evacuation are proposed, which can be applied to the actual situation under traffic control.

  5. Scaling relation between earthquake magnitude and the departure time from P wave similar growth

    USGS Publications Warehouse

    Noda, Shunta; Ellsworth, William L.

    2016-01-01

    We introduce a new scaling relation between earthquake magnitude (M) and a characteristic of initial P wave displacement. By examining Japanese K-NET data averaged in bins partitioned by Mw and hypocentral distance, we demonstrate that the P wave displacement briefly displays similar growth at the onset of rupture and that the departure time (Tdp), which is defined as the time of departure from similarity of the absolute displacement after applying a band-pass filter, correlates with the final M in a range of 4.5 ≤ Mw ≤ 7. The scaling relation between Mw and Tdp implies that useful information on the final M can be derived while the event is still in progress because Tdp occurs before the completion of rupture. We conclude that the scaling relation is important not only for earthquake early warning but also for the source physics of earthquakes.

  6. Understanding patch departure rules for large carnivores: lion movements support a patch-disturbance hypothesis.

    PubMed

    Valeix, Marion; Chamaillé-Jammes, Simon; Loveridge, Andrew J; Davidson, Zeke; Hunt, Jane E; Madzikanda, Hillary; Macdonald, David W

    2011-08-01

    We test two hypotheses that could account for patch departure by large mammalian carnivores. One hypothesis is the unsuccessful-hunt hypothesis, where carnivores leave an area after an unsuccessful hunt but continue hunting in the same area after a successful hunt. The second hypothesis is the patch-disturbance hypothesis, where carnivores depart the area after a successful hunt because of behavioral responses of prey to predator presence. We used global positioning system collars to monitor the movements of African lions (Panthera leo) and identified their kill sites to distinguish between these two hypotheses. Lions moved to a different area (≥ 5 km away) after 87% of the kills, which supports the patch-disturbance hypothesis for patch-departure behavior of large mammalian carnivores.

  7. Bounds for departure from normality and the Frobenius norm of matrix eigenvalues

    SciTech Connect

    Lee, S.L.

    1994-12-01

    New lower and upper bounds for the departure from normality and the Frobenius norm of the eigenvalues of a matrix axe given. The significant properties of these bounds axe also described. For example, the upper bound for matrix eigenvalues improves upon the one derived by Kress, de Vries and Wegmann in [Lin. Alg. Appl., 8 (1974), pp. 109-120]. The upper bound for departure from normality is sharp for any matrix whose eigenvalues are collinear in the complex plane. Moreover, the latter formula is a practical estimate that costs (at most) 2m multiplications, where m is the number of nonzeros in the matrix. In terms of applications, the results can be used to bound from above the sensitivity of eigenvalues to matrix perturbations or bound from below the condition number of the eigenbasis of a matrix.

  8. Wake Turbulence Mitigation for Departures (WTMD) Prototype System - Software Design Document

    NASA Technical Reports Server (NTRS)

    Sturdy, James L.

    2008-01-01

    This document describes the software design of a prototype Wake Turbulence Mitigation for Departures (WTMD) system that was evaluated in shadow mode operation at the Saint Louis (KSTL) and Houston (KIAH) airports. This document describes the software that provides the system framework, communications, user displays, and hosts the Wind Forecasting Algorithm (WFA) software developed by the M.I.T. Lincoln Laboratory (MIT-LL). The WFA algorithms and software are described in a separate document produced by MIT-LL.

  9. Individual variation affects departure rate from the natal pond in an ephemeral pond-breeding anuran

    USGS Publications Warehouse

    Chelgren, N.D.; Rosenberg, D.K.; Heppell, S.S.; Gitelman, A.I.

    2008-01-01

    Frogs exhibit extreme plasticity and individual variation in growth and behavior during metamorphosis, driven by interactions of intrinsic state factors and extrinsic environmental factors. In northern red-legged frogs (Rana aurora Baird and Girard, 1852), we studied the timing of departure from the natal pond as it relates to date and size of individuals at metamorphosis in the context of environmental uncertainty. To affect body size at metamorphosis, we manipulated food availability during the larval stage for a sample (317) of 1045 uniquely marked individuals and released them at their natal ponds as newly metamorphosed frogs. We recaptured 34% of marked frogs in pitfall traps as they departed and related the timing of their initial terrestrial movements to individual properties using a time-to-event model. Median age at first capture was 4 and 9 days postmetamorphosis at two sites. The rate of departure was positively related to body size and to date of metamorphosis. Departure rate was strongly negatively related to time elapsed since rainfall, and this effect was diminished for smaller and later metamorphosing frogs. Individual variation in metamorphic traits thus affects individuals' responses to environmental variability, supporting a behavioral link with variation in survival associated with these same metamorphic traits. ?? 2008 NRC.

  10. Patch departure decisions by spice finches foraging singly or in groups

    PubMed

    Livoreil; Giraldeau

    1997-10-01

    The marginal value theorem predicts that when resources are clumped in space, a forager can maximize its rate of intake by deciding to leave a patch when its current feeding rate falls below the average for the habitat. A group version of the model predicts that when rate-maximizing group members share a patch, they should leave sooner, and each with less gain, than single animals exploiting the same patch. We tested these predictions in the laboratory by measuring patch departure decisions of spice finches, Lonchura punctulataexploiting food patches alone or in groups of three under two habitats that require different travel times. As predicted, group members left the patch sooner and with fewer seeds than single foragers. Unlike the model's assumptions, however, birds did not share the patch equally, and their exploitation curves could not be simply derived from those of single foragers. Grouping decreased the effect of travel time on patch exploitation. Moreover, within each group the bird expected to leave first delayed its departure although it collected fewer seeds than the others. This delayed departure could aim to maintain group membership. We noted an increased variability in seed number collected by group members compared with single foragers, which could be a cost of group foraging.Copyright 1997 The Association for the Study of Animal Behaviour1997The Association for the Study of Animal Behaviour

  11. Effect of Earth and Mars departure delays on human missions to Mars

    NASA Technical Reports Server (NTRS)

    Desai, Prasun N.; Tartabini, Paul V.

    1993-01-01

    This study determines the impact on the initial mass in low-Earth orbit (IMLEO) for delaying departure from Mars and Earth by 5, 15, and 30 days, once a nominal mission to Mars has been selected. Additionally, the use of a deep space maneuver (DSM) is attempted to alleviate the IMLEO penalties. Three different classes of missions are analyzed using chemical and nuclear thermal propulsion systems in the 2000-2025 time-frame: opposition, conjunction, and fast-transfer conjunction. The results indicate that Mars and Earth delays can lead to large IMLEO penalties. Opposition and fast-transfer conjunction class missions have the highest IMLEO penalties, upwards of 432.4 mt and 1977.3 mt, respectively. Conjunction class missions, on the other hand, tend to be insensitive to Mars and Earth delays having IMLEO penalties under 103.5 mt. As expected, nuclear thermal propulsion had significantly lower IMLEO penalties as compared to chemical propulsion. The use of a DSM is found not to have a significant impact on reducing the IMLEO penalties. Through this investigation, the effect of off-nominal departure conditions on the overall mission (i.e., IMLEO) can be gained, enabling mission designers to incorporate the influence of off-nominal departure conditions of the interplanetary trajectory in the overall conceptual design process of a Mars transfer vehicle.

  12. Framework for determining airport daily departure and arrival delay thresholds: statistical modelling approach.

    PubMed

    Wesonga, Ronald; Nabugoomu, Fabian

    2016-01-01

    The study derives a framework for assessing airport efficiency through evaluating optimal arrival and departure delay thresholds. Assumptions of airport efficiency measurements, though based upon minimum numeric values such as 15 min of turnaround time, cannot be extrapolated to determine proportions of delay-days of an airport. This study explored the concept of delay threshold to determine the proportion of delay-days as an expansion of the theory of delay and our previous work. Data-driven approach using statistical modelling was employed to a limited set of determinants of daily delay at an airport. For the purpose of testing the efficacy of the threshold levels, operational data for Entebbe International Airport were used as a case study. Findings show differences in the proportions of delay at departure (μ = 0.499; 95 % CI = 0.023) and arrival (μ = 0.363; 95 % CI = 0.022). Multivariate logistic model confirmed an optimal daily departure and arrival delay threshold of 60 % for the airport given the four probable thresholds {50, 60, 70, 80}. The decision for the threshold value was based on the number of significant determinants, the goodness of fit statistics based on the Wald test and the area under the receiver operating curves. These findings propose a modelling framework to generate relevant information for the Air Traffic Management relevant in planning and measurement of airport operational efficiency. PMID:27441145

  13. Forty Years on: Presidential Address to the History of Education Society, London, 4 November 2006

    ERIC Educational Resources Information Center

    McCulloch, Gary

    2007-01-01

    This paper, based on the author's presidential address to the History of Education Society in November 2006, explores aspects of continuity and change over the past 40 years with particular reference to educational reform and the development of the History of Education Society itself. It assesses the significance of the work of the playwright Alan…

  14. BERA Presidential Address 2013: Educational Research--What's to Be Done?

    ERIC Educational Resources Information Center

    Menter, Ian

    2014-01-01

    In his inaugural Presidential Address, given to the BERA Conference 2013 at the University of Sussex, Ian Menter addresses a number of issues concerning educational policy and the contributions that educational research might make to policy development. As BERA approaches its fortieth anniversary, he also sets out some of the responsibilities that…

  15. Presidential and bureaucratic policy-making: The case of Mexican oil policy

    SciTech Connect

    de la Luz Valverde Rocha, M.

    1991-01-01

    A close examination of the literature yielded two different, but vague models of Mexican policy-making: (1) closed presidential policy-making and (2) open presidential policy-making. These two models are tested by identifying the regime's policy-making structures and by explaining the manner in which they operated to produce oil policy in two presidential administrations. To attain these goals, the oil policy-making process was divided into several stages. The policy roles played by different actors in the various stages of policy-making were analyzed. The process they engaged in to produce oil policy was also examined. The findings lend strong support to the open presidential policy-making model. The most salient features of this model are: (1) the president and different members of the Mexican federal bureaucracy share policy-making functions, power, and influence; (2) policymakers engage in a political process of persuasion, coalition building, information functions, power, and influence; and (3) policymakers engage in these and other political techniques to produce government decisions and actions.

  16. Asserting the Possible: Gunzenhauser's "Ethics of the Everyday." Response to the Presidential Address

    ERIC Educational Resources Information Center

    Worley, Virginia

    2013-01-01

    In this article, the author responds to the Presidential address, "Ethics for the New Political Economy: What Can It Mean to Be Professionally Responsible?" in which Michael G. Gunzenhauser defines, names, and proposes a professional ethics for educators: an ethics of the everyday. The author introduces her response by stating that…

  17. The Effect of Religion on Candidate Preference in the 2008 and 2012 Republican Presidential Primaries.

    PubMed

    Bradberry, Leigh A

    2016-01-01

    Thanks to the work of politics and religion scholars, we now know a lot about the relationship between religion and voting in American presidential general elections. However, we know less about the influence of religion on individual vote choice in presidential primaries. This article fills that gap by exploring the relationship between religion and candidate preference in the 2008 and 2012 Republican primaries. Using pre-Super Tuesday surveys conducted by the Pew Research Center, I find that the Republican candidate who most explicitly appealed to religious voters (Mike Huckabee in 2008 and Rick Santorum in 2012) was the preferred candidate of Republican respondents who attended religious services at the highest levels, and that as attendance increased, so did the likelihood of preferring that candidate. I also find that identification as a born again Christian mattered to candidate preference. Specifically, born again Christians were more likely than non-born again Christians to prefer Huckabee to Mitt Romney, John McCain and Ron Paul in 2008, and Santorum to Romney in 2012. Although ideology was not the primary subject of this article, I find that ideology was also a statistically significant predictor of Republican candidate preference in both 2008 and 2012. This robust finding reinforces scholars' prior work on the importance of ideology in explaining presidential primary vote choice. The overall findings of the paper provide evidence that religion variables can add to our understanding of why voters prefer one candidate over another in presidential primaries.

  18. The Camp David Ceremony and the Genre of the Presidential Parasocial Broadcast Announcement.

    ERIC Educational Resources Information Center

    Houser, William Evan

    In 1978, the historic Camp David Peace Accords between Egypt and Israel were signed in a ceremony broadcast from the White House. The ceremony may be seen as a member of a rhetorical genre informally called the Presidential Parasocial Broadcast Announcement, but with a new twist. The genre has its roots in the Fireside Chats of Franklin D.…

  19. 75 FR 2546 - Meeting of the Presidential Advisory Council on HIV/AIDS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-15

    ... HUMAN SERVICES Meeting of the Presidential Advisory Council on HIV/AIDS AGENCY: Department of Health and Human Services, Office of the Secretary, Office of Public Health and Science. ACTION: Notice. SUMMARY: As stipulated by the Federal Advisory Committee Act, the U.S. Department of Health and Human...

  20. Rutherford B. Hayes Presidential Center Library and Archives: Patron Use of Collections and Services.

    ERIC Educational Resources Information Center

    Grove, Myrna J.

    The Rutherford B. Hayes Library opened in 1916, when the building in Fremont, Ohio was dedicated as the first presidential library and museum. The library's original purpose was to preserve the 12,000 volume personal library of President Hayes along with archival material from his careers in law, the military, and politics. This was a radical idea…