Science.gov

Sample records for 20-year time horizon

  1. New Horizons 20 Years On. Occasional Papers Series: No. 7.

    ERIC Educational Resources Information Center

    Gordon, Margaret

    New Horizons is a course offered by the University of Edinburgh's Centre for Continuing Education that is aimed at first-time returners to education. In the 20 years since New Horizons was developed for women returners to education and/or employment, it has retained its original developmental outcomes but broadened its target group in response to…

  2. CAHRD Consultation 2014: the 10-20 year Horizon Introduction and Overview – as circulated to Consultation participants

    PubMed Central

    2015-01-01

    The overall aim of the 2014 Consultation is to bring together internal and external partners to help shape the strategic direction for CAHRD over the 10 to 20 year horizon. Our strategic thinking will be guided by our vision of a healthy future for low and middle income populations and our mission to transform health systems to improve the health of these populations. Partnership between northern and southern institutions is integral to this work and critical in the consultation process. The Consultation considers four selected areas of the current work of CAHRD: Lung Health, Maternal & Newborn Health, Neglected Tropical Diseases, and Health Systems. We aim to foster dialogue and learning between these and across contexts and disciplines. The major challenges that will need to be addressed over the next 10 to 20 years will be scoped and pathways to possible solutions proposed. The overall vision is a process of co-production of knowledge

  3. Insights into the dynamics of Etna volcano from 20-year time span microgravity and GPS observations

    NASA Astrophysics Data System (ADS)

    Bonforte, Alessandro; Fanizza, Giovanni; Greco, Filippo; Matera, Alfredo; Sulpizio, Roberto

    2016-04-01

    A common ground deformation and microgravity array of benchmarks lies on the southern slope of Mt. Etna volcano and is routinely measured by GPS and relative gravimetry methods. The array was installed for monitoring the ground motion and underground mass changes along the southern rift of the volcano and data are usually processed and interpreted independently. The benchmarks have been installed mainly along a main road crossing the southern side of the volcano with an E-W direction and reaching 2000 m of altitude. The gravity array covers the entire path of the road, while the ground deformation one only the upper one, due to the woods at lower altitude preventing good GPS measurements. Furthermore, microgravity surveys are usually carried out more frequently with respect to the GPS ones. In this work, an integrated analysis of microgravity and ground deformation is performed over a 20-year time span (1994-2014). Gravity variations have been first corrected for the free-air effect using the GPS observed vertical deformation and the theoretical vertical gravity gradient (-308.6 μGal/m). The free-air corrected gravity changes were then reduced from the high frequency variations (noise) and the seasonal fluctuations, mainly due to water-table fluctuations. This long-term dataset constitutes a unique opportunity to examine the behavior of Etna in a period in which the volcano exhibited different styles of activity characterized by recharging phases, flank eruptions and fountaining episodes. The gravity and deformation data allow investigating the response of the volcano in a wider perspective providing insights into the definition of its dynamic behavior and posing the basis to track the unrest evolution and to forecast the style of the eruption. The joint analysis highlights common periods, in which the signals underwent contemporaneous changes occurring mainly in the central and eastern stations. On the other hand, no significant changes in the behavior of

  4. Time Horizon in Students' Predictions of Grades.

    ERIC Educational Resources Information Center

    Manger, Terje; Teigen, Karl Halvor

    1988-01-01

    Eight and two months before their final exam, 252 undergraduates in Norway stated their expectations and hopes for examination grades. Correlations between expected and obtained grades were low. A shift from optimism to pessimism occurred. Results confirm the time horizon's crucial role in the prediction of academic achievement. (TJH)

  5. Time Horizon and Social Scale in Communication

    NASA Astrophysics Data System (ADS)

    Krantz, D. H.

    2010-12-01

    In 2009 our center (CRED) published a first version of The Psychology of Climate Change Communication. In it, we attempted to summarize facts and concepts from psychological research that could help guide communication. While this work focused on climate change, most of the ideas are at least partly applicable for communication about a variety of natural hazards. Of the many examples in this guide, I mention three. Single-action bias is the human tendency to stop considering further actions that might be needed to deal with a given hazard, once a single action has been taken. Another example is the importance of group affiliation in motivating voluntary contributions to joint action. A third concerns the finding that group participation enhances understanding of probabilistic concepts and promotes action in the face of uncertainty. One current research direction, which goes beyond those included in the above publication, focuses on how time horizons arise in the thinking of individuals and groups, and how these time horizons might influence hazard preparedness. On the one hand, individuals sometimes appear impatient, organizations look for immediate results, and officials fail to look beyond the next election cycle. Yet under some laboratory conditions and in some subcultures, a longer time horizon is adopted. We are interested in how time horizon is influenced by group identity and by the very architecture of planning and decision making. Institutional changes, involving long-term contractual relationships among communities, developers, insurers, and governments, could greatly increase resilience in the face of natural hazards. Communication about hazards, in the context of such long-term contractual relationships might look very different from communication that is first initiated by immediate threat. Another new direction concerns the social scale of institutions and of communication about hazards. Traditionally, insurance contracts share risk among a large

  6. Horizons versus singularities in spherically symmetric space-times

    SciTech Connect

    Bronnikov, K. A.; Elizalde, E.; Odintsov, S. D.; Zaslavskii, O. B.

    2008-09-15

    We discuss different kinds of Killing horizons possible in static, spherically symmetric configurations and recently classified as 'usual', 'naked', and 'truly naked' ones depending on the near-horizon behavior of transverse tidal forces acting on an extended body. We obtain the necessary conditions for the metric to be extensible beyond a horizon in terms of an arbitrary radial coordinate and show that all truly naked horizons, as well as many of those previously characterized as naked and even usual ones, do not admit an extension and therefore must be considered as singularities. Some examples are given, showing which kinds of matter are able to create specific space-times with different kinds of horizons, including truly naked ones. Among them are fluids with negative pressure and scalar fields with a particular behavior of the potential. We also discuss horizons and singularities in Kantowski-Sachs spherically symmetric cosmologies and present horizon regularity conditions in terms of an arbitrary time coordinate and proper (synchronous) time. It turns out that horizons of orders 2 and higher occur in infinite proper times in the past or future, but one-way communication with regions beyond such horizons is still possible.

  7. Trend analysis of the 20 years time series of stratospheric ozone profiles observed by the GROMOS microwave radiometer at Bern

    NASA Astrophysics Data System (ADS)

    Moreira, L.; Hocke, K.; Eckert, E.; von Clarmann, T.; Kämpfer, N.

    2015-06-01

    The ozone radiometer GROMOS (GROund-based Millimeterwave Ozone Spectrometer) performs continuous observations of stratospheric ozone profiles since 1994 above Bern, Switzerland. GROMOS is part of the Network for the Detection of Atmospheric Composition Change (NDACC). From November 1994 to October 2011, the ozone line spectra were measured by a filter bench (FB). In July 2009, a Fast-Fourier-Transform spectrometer (FFTS) has been added as backend to GROMOS. The new FFTS and the original FB measured in parallel for over two years. The ozone profiles retrieved separately from the ozone line spectra of FB and FFTS agree within 5 % at pressure levels from 30 to 0.5 hPa, from October 2009 to August 2011. A careful harmonisation of both time series has been carried out by taking the FFTS as the reference instrument for the FB. This enables us to assess the long-term trend derived from more than 20 years of stratospheric ozone observations at Bern. The trend analysis has been performed by using a robust multilinear parametric trend model which includes a linear term, the solar variability, the El Niño-Southern Oscillation (ENSO) index, the quasi-biennial oscillation (QBO), the annual and semi-annual oscillation and several harmonics with period lengths between 3 and 24 months. Over the last years, some experimental and modelling trend studies have shown that the stratospheric ozone trend is levelling off or even turning positive. With our observed ozone profiles, we are able to support this statement by reporting a statistically significant trend of +3.14 % decade-1 at 4.36 hPa, covering the period from January 1997 to January 2015, above Bern. Additionally, we have estimated a negative trend over this period of -3.94 % decade-1 at 0.2 hPa.

  8. The WSMR Timing System: Toward New Horizons

    NASA Technical Reports Server (NTRS)

    Gilbert, William A.; Stimets, Bob

    1996-01-01

    In 1991, White Sands Missile Range (WSMR) initiated a modernization program for its range timing system. The main focus of this modernization program was to develop a system that was highly accurate, easy to maintain, and portable. The logical decision at the time was to develop a system based solely on Global Positioning System (GPS) technology. Since that time, wsmr has changed its philosophy on how GPS would be utilized for the timing system. This paper will describe WSMR's initial modernization plans for its range timing system and how certain events have led to a modification of these plans.

  9. Yearbook 1988. IWGIA: 20 Years.

    ERIC Educational Resources Information Center

    Gray, Andrew

    The theme of this yearbook is the work of the International Work Group for Indigenous Affairs (IWGIA) during the 20 years of its existence and the enormous growth of the indigenous movement in that time. Section 1 traces IWGIA's history and includes the annual report for 1988. Section 2 is a global view of the main events in the indigenous world…

  10. Trend analysis of the 20-year time series of stratospheric ozone profiles observed by the GROMOS microwave radiometer at Bern

    NASA Astrophysics Data System (ADS)

    Moreira, L.; Hocke, K.; Eckert, E.; von Clarmann, T.; Kämpfer, N.

    2015-10-01

    The ozone radiometer GROMOS (GROund-based Millimeter-wave Ozone Spectrometer) has been performing continuous observations of stratospheric ozone profiles since 1994 above Bern, Switzerland (46.95° N, 7.44° E, 577 m). GROMOS is part of the Network for the Detection of Atmospheric Composition Change (NDACC). From November 1994 to October 2011, the ozone line spectra were measured by a filter bench (FB). In July 2009, a fast Fourier transform spectrometer (FFTS) was added as a back end to GROMOS. The new FFTS and the original FB measured in parallel for over 2 years. The ozone profiles retrieved separately from the ozone line spectra of FB and FFTS agree within 5 % at pressure levels from 30 to 0.5 hPa, from October 2009 to August 2011. A careful harmonisation of both time series has been carried out by taking the FFTS as the reference instrument for the FB. This enables us to assess the long-term trend derived from stratospheric ozone observations at Bern. The trend analysis was performed by using a robust multilinear parametric trend model which includes a linear term, the solar variability, the El Niño-Southern Oscillation (ENSO) index, the quasi-biennial oscillation (QBO), the annual and semi-annual oscillation and several harmonics with period lengths between 3 and 24 months. Over the last years, some experimental and modelling trend studies have shown that the stratospheric ozone trend is levelling off or even turning positive. With our observed ozone profiles, we are able to support this statement by reporting a statistically significant trend of +3.14 % decade-1 at 4.36 hPa (37.76 km), covering the period from January 1997 to January 2015, above Bern. Additionally, we have estimated a negative trend over this period of -3.94 % decade-1 at 0.2 hPa (59 km).

  11. Time machines with the compactly determined Cauchy horizon

    NASA Astrophysics Data System (ADS)

    Krasnikov, S.

    2014-07-01

    The building of a time machine, if possible at all, requires the relevant regions of spacetime to be compact (that is, physically speaking, free from sources of unpredictability such as infinities and singularities). Motivated by this argument we consider the spacetimes with the compactly determined Cauchy horizons (CDCHs), the defining property of which is the compactness of J-(U) ¯∩J+(S0), where U is an open subset of the Cauchy horizon and S0 is a Cauchy surface of the initial globally hyperbolic region Min. The following two facts are established: (1) Min has no globally hyperbolic maximal extension. This means that, by shaping appropriately a precompact portion of a globally hyperbolic region, one can force the Universe to produce either a closed causal curve, or a quasiregular singularity, whichever it abhors less. (2) Before a CDCH is formed a null geodesic appears which infinitely approaches the horizon returning again and again in the same—arbitrarily small—region. The energy of the photon moving on such a geodesic increases with each passage, or at least falls insufficiently fast. As a result, an observer located in the mentioned region would see a bunch of photons passing through his laboratory with the arbitrarily large total energy. We speculate that this phenomenon may have observable consequences.

  12. Generalized Robertson-Walker Space-Time Admitting Evolving Null Horizons Related to a Black Hole Event Horizon

    PubMed Central

    2016-01-01

    A new technique is used to study a family of time-dependent null horizons, called “Evolving Null Horizons” (ENHs), of generalized Robertson-Walker (GRW) space-time (M¯,g¯) such that the metric g¯ satisfies a kinematic condition. This work is different from our early papers on the same issue where we used (1 + n)-splitting space-time but only some special subcases of GRW space-time have this formalism. Also, in contrast to previous work, we have proved that each member of ENHs is totally umbilical in (M¯,g¯). Finally, we show that there exists an ENH which is always a null horizon evolving into a black hole event horizon and suggest some open problems. PMID:27722202

  13. Time horizon dependent characterization factors for acidification in life-cycle assessment based on forest plant species occurrence in Europe

    SciTech Connect

    Rosalie van Zelm; Mark A.J. Huijbregts; Hans A. van Jaarsveld; Gert Jan Reinds; Dick de Zwart; Jaap Struijs; Dik van de Meent

    2007-02-15

    This paper describes a new approach in life-cycle impact assessment to derive characterization factors for acidification in European forests. Time horizon dependent characterization factors for acidification were calculated, whereas before only steady-state factors were available. The characterization factors indicate the change in the potential occurrence of plant species due to a change in emission, and they consist of a fate and an effect factor. The fate factor combines the results of an atmospheric deposition model and a dynamic soil acidification model. The change in base saturation in soil due to an atmospheric emission change was derived for 20, 50, 100, and 500 year time horizons. The effect factor was based on a dose-response curve of the potential occurrence of plant species, derived from multiple regression equations per plant species. The results showed that characterization factors for acidification increase up to a factor of 13 from a 20 years to a 500 years time horizon. Characterization factors for ammonia are 4.0-4.3 times greater than those for nitrogen oxides (NOx), and characterization factors for sulfur dioxide are 1.4-2.0 times greater than those for NOx. Aggregation of damage due to acidification with other impact categories on the European scale becomes feasible with the applied approach. 45 refs., 3 figs., 1 tab.

  14. Time horizon dependent characterization factors for acidification in life-cycle assessment based on forest plant species occurrence in Europe.

    PubMed

    Van Zelm, Rosalie; Huijbregts, Mark A J; van Jaarsveld, Hans A; Reinds, Gert Jan; de Zwart, Dick; Struijs, Jaap; van de Meent, Dik

    2007-02-01

    This paper describes a new approach in life-cycle impact assessment to derive characterization factors for acidification in European forests. Time horizon dependent characterization factors for acidification were calculated, whereas before only steady-state factors were available. The characterization factors indicate the change in the potential occurrence of plant species due to a change in emission, and they consist of a fate and an effect factor. The fate factor combines the results of an atmospheric deposition model and a dynamic soil acidification model. The change in base saturation in soil due to an atmospheric emission change was derived for 20, 50, 100, and 500 year time horizons. The effect factor was based on a dose-response curve of the potential occurrence of plant species, derived from multiple regression equations per plant species. The results showed that characterization factors for acidification increase up to a factor of 13 from a 20 years to a 500 years time horizon. Characterization factors for ammonia are 4.0-4.3 times greater than those for nitrogen oxides (NO(x)), and characterization factors for sulfur dioxide are 1.4-2.0 times greater than those for NO(x). Aggregation of damage due to acidification with other impact categories on the European scale becomes feasible with the applied approach.

  15. Celebrating 20 Years of Hubble

    NASA Video Gallery

    NASA's Hubble Space Telescope began a remarkable journey of discovery on April 24, 1990. After 20 years in space, the observatory has shown humanity more of the universe than ever before. With the ...

  16. Receding Horizon Stabilization and Disturbance Attenuation for Neural Networks With Time-Varying Delay.

    PubMed

    Ahn, Choon Ki; Shi, Peng; Wu, Ligang

    2015-12-01

    This paper is concerned with the problems of receding horizon stabilization and disturbance attenuation for neural networks with time-varying delay. New delay-dependent conditions on the terminal weighting matrices of a new finite horizon cost functional for receding horizon stabilization are established for neural networks with time-varying or time-invariant delays using single- and double-integral Wirtinger-type inequalities. Based on the results, delay-dependent sufficient conditions for the receding horizon disturbance attenuation are given to guarantee the infinite horizon H∞ performance of neural networks with time-varying or time-invariant delays. Three numerical examples are provided to illustrate the effectiveness of the proposed approach.

  17. Deepwater Horizon - Estimating surface oil volume distribution in real time

    NASA Astrophysics Data System (ADS)

    Lehr, B.; Simecek-Beatty, D.; Leifer, I.

    2011-12-01

    Spill responders to the Deepwater Horizon (DWH) oil spill required both the relative spatial distribution and total oil volume of the surface oil. The former was needed on a daily basis to plan and direct local surface recovery and treatment operations. The latter was needed less frequently to provide information for strategic response planning. Unfortunately, the standard spill observation methods were inadequate for an oil spill this size, and new, experimental, methods, were not ready to meet the operational demands of near real-time results. Traditional surface oil estimation tools for large spills include satellite-based sensors to define the spatial extent (but not thickness) of the oil, complemented with trained observers in small aircraft, sometimes supplemented by active or passive remote sensing equipment, to determine surface percent coverage of the 'thick' part of the slick, where the vast majority of the surface oil exists. These tools were also applied to DWH in the early days of the spill but the shear size of the spill prevented synoptic information of the surface slick through the use small aircraft. Also, satellite images of the spill, while large in number, varied considerably in image quality, requiring skilled interpretation of them to identify oil and eliminate false positives. Qualified staff to perform this task were soon in short supply. However, large spills are often events that overcome organizational inertia to the use of new technology. Two prime examples in DWH were the application of hyper-spectral scans from a high-altitude aircraft and more traditional fixed-wing aircraft using multi-spectral scans processed by use of a neural network to determine, respectively, absolute or relative oil thickness. But, with new technology, come new challenges. The hyper-spectral instrument required special viewing conditions that were not present on a daily basis and analysis infrastructure to process the data that was not available at the command

  18. SeaWiFS technical report series. Volume 17: Ocean color in the 21st century. A strategy for a 20-year time series

    NASA Technical Reports Server (NTRS)

    Abbott, Mark R.; Brown, Otis B.; Evans, Robert H.; Gordon, Howard R.; Carder, Kendall L.; Mueller-Karger, Frank E.; Esaias, Wayne E.; Hooker, Stanford B.; Firestone, Elaine R.

    1994-01-01

    Beginning with the upcoming launch of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), there should be almost continuous measurements of ocean color for nearly 20 years if all of the presently planned national and international missions are implemented. This data set will present a unique opportunity to understand the coupling of physical and biological processes in the world ocean. The presence of multiple ocean color sensors will allow the eventual development of an ocean color observing system that is both cost effective and scientifically based. This report discusses the issues involved and makes recommendations intended to ensure the maximum scientific return from this unique set of planned ocean color missions. An executive summary is included with this document which briefly discusses the primary issues and suggested actions to be considered.

  19. CT Angiography after 20 Years

    PubMed Central

    Rubin, Geoffrey D.; Leipsic, Jonathon; Schoepf, U. Joseph; Fleischmann, Dominik; Napel, Sandy

    2015-01-01

    Through a marriage of spiral computed tomography (CT) and graphical volumetric image processing, CT angiography was born 20 years ago. Fueled by a series of technical innovations in CT and image processing, over the next 5–15 years, CT angiography toppled conventional angiography, the undisputed diagnostic reference standard for vascular disease for the prior 70 years, as the preferred modality for the diagnosis and characterization of most cardiovascular abnormalities. This review recounts the evolution of CT angiography from its development and early challenges to a maturing modality that has provided unique insights into cardiovascular disease characterization and management. Selected clinical challenges, which include acute aortic syndromes, peripheral vascular disease, aortic stent-graft and transcatheter aortic valve assessment, and coronary artery disease, are presented as contrasting examples of how CT angiography is changing our approach to cardiovascular disease diagnosis and management. Finally, the recently introduced capabilities for multispectral imaging, tissue perfusion imaging, and radiation dose reduction through iterative reconstruction are explored with consideration toward the continued refinement and advancement of CT angiography. PMID:24848958

  20. Correlation based networks of equity returns sampled at different time horizons

    NASA Astrophysics Data System (ADS)

    Tumminello, M.; di Matteo, T.; Aste, T.; Mantegna, R. N.

    2007-01-01

    We investigate the planar maximally filtered graphs of the portfolio of the 300 most capitalized stocks traded at the New York Stock Exchange during the time period 2001 2003. Topological properties such as the average length of shortest paths, the betweenness and the degree are computed on different planar maximally filtered graphs generated by sampling the returns at different time horizons ranging from 5 min up to one trading day. This analysis confirms that the selected stocks compose a hierarchical system progressively structuring as the sampling time horizon increases. Finally, a cluster formation, associated to economic sectors, is quantitatively investigated.

  1. [Neurogenic bladder, 20 years later].

    PubMed

    Perrigot, M

    1995-10-28

    The therapeutic armamentarium--physical therapy, drugs, surgery--developed over the last 20 years now gives us the means of providing curative care to nearly all patients with manifestations of neuropathic bladder, meaning that the clinical examination and complementary tests must be conducted under strictly controlled conditions to identify the underlying mechanism. The examination of the perineum almost always reveals a defect when the origin is neurological but is often normal when gynaecologic or urologic factors are involved. Motor command, tonus, reflexes and sensitivity should all be carefully explored to distinguish between central and peripheral causes. Much progress has been made in complementary examinations. For example, nearly 100% of the neurological aetiologies can be identified with precision. Tests include electromyography of the perineum, measurement of the latency of the bulbocavernous reflex and that of the distal part of the internal pudental nerve. Complementary tests evaluating bladder and sphincter function include urine sediment with cytology, intravenous pyelography and echography of the urinary tract. Pressure measurements with cystomanometry, sphincterometry and flowmetry add further precisions. Whether the underlying mechanism of bladder dysfunction is purely neurological as is the case in many young patients with multiple sclerosis, spina bifida or caudia equina syndrome, results from several causes as in patients with Parkinson's disease and enlargement of the prostate, or is among the increasing number of post-radiation sequellae, the essential step is careful clinical examination and detailed interpretation of complementary examinations. Thus the wide range of techniques now available for the management of the neuropathic bladder can be adapted to each individual case according to the pathological processes causing the clinical manifestations. PMID:8545359

  2. Change in predominance of Bovine viral diarrhea virus subgenotypes among samples submitted to a diagnostic laboratory over a 20-year time span.

    PubMed

    Ridpath, Julia F; Lovell, Gayla; Neill, John D; Hairgrove, Thomas B; Velayudhan, Binu; Mock, Richard

    2011-03-01

    Although the causative agent of bovine viral diarrhea was initially categorized as 1 species, phylogenetic analysis revealed that these viruses belong to 2 different species, Bovine viral diarrhea virus 1 (BVDV-1) and BVDV-2, with 2-11 subgenotypes within each species. Distribution of species and subgenotypes has been shown to vary with geographic region. Whether distribution shifts over time is not known. Surveys conducted between 1994 and 2008 reported 3 subgenotypes circulating among cattle in the United States: BVDV-1a, BVDV-1b, and BVDV-2a. The average percent prevalence of BVDV-1a, BVDV-1b, and BVDV-2a strains reported in surveys before 2001 were 21%, 43%, and 36%, respectively. Surveys conducted on viruses isolated after 2001 reported decreasing percentages of BVDV-1a and BVDV-2a strains, with BVDV-1b strains accounting for 75-100% of samples. Comparison of these surveys is confounded by differences in geographic location, collection methods, and sample type used in the survey. The purpose of the present study was to determine whether the prevalence of BVDV subgenotypes shifted in samples collected from the same geographic region and by the same laboratory over time. BVDV strains isolated in years 1988, 1998, and 2008, at the Texas Veterinary Medical Diagnostic Laboratory, Amarillo, Texas, were genotyped, and the prevalence of BVDV-1a, BVDV-1b, and BVDV-2a strains were determined. Typing, on the basis of phylogenetic analysis, was done on 148 samples. The strongest trend detected among these samples was a pronounced decrease in the number of BVDV-1a strains over time.

  3. 75 FR 79961 - Temporary Suspension of Certain Oil Spill Response Time Requirements To Support Deepwater Horizon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-21

    ... Gulf of Mexico Deepwater Horizon SONSat the FOSC's request. 75 FR 37712. The rule also confirmed that...; 2050-AG63 Temporary Suspension of Certain Oil Spill Response Time Requirements To Support Deepwater.... Oil Spill Response Resources Return Time Several comments noted concerns about the return of assets...

  4. An integral equation representation approach for valuing Russian options with a finite time horizon

    NASA Astrophysics Data System (ADS)

    Jeon, Junkee; Han, Heejae; Kim, Hyeonuk; Kang, Myungjoo

    2016-07-01

    In this paper, we first describe a general solution for the inhomogeneous Black-Scholes partial differential equation with mixed boundary conditions using Mellin transform techniques. Since Russian options with a finite time horizon are usually formulated into the inhomogeneous free-boundary Black-Scholes partial differential equation with a mixed boundary condition, we apply our method to Russian options and derive an integral equation satisfied by Russian options with a finite time horizon. Furthermore, we present some numerical solutions and plots of the integral equation using recursive integration methods and demonstrate the computational accuracy and efficiency of our method compared to other competing approaches.

  5. Self-regulation predicts risk-taking through people's time horizon.

    PubMed

    Panno, Angelo; Pierro, Antonio; Lauriola, Marco

    2014-06-01

    In the context of decision-making research, people's regulatory orientation mode (i.e., assessment and locomotion modes) has been included among the most prominent individual difference variables, which may potentially account for choice behaviour. Thus, the main objective of our experiment was to investigate the relations between habitual use of regulatory mode and risk-taking through people's time horizon. Risk-taking was appraised using a behavioural measure (i.e., BART) 1 month following evaluation of habitual use of regulatory mode. The findings revealed a significant negative association between the assessment mode and risk-taking through individual differences in time horizon. PMID:24821511

  6. [Vaccination against hepatitis B. Impact of vaccination programmes after 20 years of use in Spain. Is it time for a change?].

    PubMed

    Arístegui Fernández, Javier; Díez-Domingo, Javier; Marés Bermúdez, Josep; Martinón Torres, Federico

    2015-02-01

    The highest incidence rate of hepatitis B (HB) in Spain is detected in adults between 20 and 54 years old, whereas the incidence in children under 1 year old is almost nil. The low prevalence of HB in children under 1 year is mainly due to the success of gestational screening strategies for the detection of HBsAg(+) in pregnant women, and vaccination campaigns during childhood. Currently, in Spain, the last dose of the HB included in the national childhood immunization program is administered at 6 months of age, although some studies show that delaying the age of the administration of the last dose of HB vaccine and increasing the time between doses, may improve immune memory by offering greater protection against this virus in the adulthood. In this article, the impact of HB vaccination in Spain is reviewed, and other potential vaccination strategies in our environment are discussed, such as extending the interval between doses, and administering the last dose in the second year of life, adapting the valid strategy in Spain to the current epidemiological context in order to reduce the prevalence of HB in adulthood.

  7. Hubble: 20 Years of Discovery

    NASA Video Gallery

    Hubble's discoveries have revolutionized nearly all areas of current astronomical research from planetary science to cosmology. Actor and writer Brent Spiner narrates a visual journey back in time ...

  8. Parisian ruin over a finite-time horizon

    NASA Astrophysics Data System (ADS)

    Dębicki, Krzysztof; Hashorva, Enkelejd; Ji, LanPeng

    2016-03-01

    For a risk process $R_u(t)=u+ct-X(t), t\\ge 0$, where $u\\ge 0$ is the initial capital, $c>0$ is the premium rate and $X(t),t\\ge 0$ is an aggregate claim process, we investigate the probability of the Parisian ruin \\[ \\mathcal{P}_S(u,T_u)=\\mathbb{P}\\{\\inf_{t\\in[0,S]} \\sup_{s\\in[t,t+T_u]} R_u(s)<0\\}, \\] with a given positive constant $S$ and a positive measurable function $T_u$. We derive asymptotic expansion of $\\mathcal{P}_S(u,T_u)$, as $u\\to\\infty$, for the aggregate claim process $X$ modeled by Gaussian processes. As a by-product, we derive the exact tail asymptotics of the infimum of a standard Brownian motion with drift over a finite-time interval.

  9. Real-time beyond the horizon vessel detection

    NASA Astrophysics Data System (ADS)

    Roarty, Hugh J.; Smith, Michael; Glenn, Scott M.; Barrick, Donald E.

    2013-05-01

    The marine transportation system (MTS) is a vital component of the United States Economy. Waterborne cargo accounts for more than $742 billion of the nation's economy and creates employment for 13 million citizens. A disruption in this system would have far reaching consequences to the security of the country. The US National High Frequency radar network, which comprises 130 radar stations around the country, became operational in May 2009. It provides hourly measurements of surface currents to the US Coast Guard for search and rescue (SAR). This system has the capability of being a dual use system providing information for environmental monitoring as well as vessel position information for maritime security. Real time vessel detection has been implemented at two of the radar stations outside New York Harbor. Several experiments were conducted to see the amount vessel traffic that the radar could capture. The radars were able to detect a majority of the vessels that are reporting via the Automatic Identification System (AIS) as well as 30 percent of mid to large size vessels that are not reporting via AIS. The radars were able to detect vessels out to 60 km from the coast. The addition of a vessel detection capability to the National HF radar network will provide valuable information to maritime security sector. This dual use capability will fill a gap in the current surveillance of US coastal waters. It will also provide longer-range situational awareness necessary to detect and track smaller size vessels in the large vessel clutter.

  10. World-sheet stability, space-time horizons and cosmic censorship

    NASA Astrophysics Data System (ADS)

    Pollock, M. D.

    2014-11-01

    Previously, we have analyzed the stability and supersymmetry of the heterotic superstring world sheet in the background Friedmann space-time generated by a perfect fluid with energy density ρ and pressure p = ( γ - 1) ρ. The world sheet is tachyon-free within the range 2/3 ≤ γ ≤ ∞, and globally supersymmetric in the Minkowski-space limit ρ = ∞, or when γ = 2/3, which is the equation of state for stringy matter and corresponds to the Milne universe, that expands along its apparent horizon. Here, this result is discussed in greater detail, particularly with regard to the question of horizon structure, cosmic censorship, the TCP theorem, and local world-sheet supersymmetry. Also, we consider the symmetric background space-time generated by a static, electrically (or magnetically) charged matter distribution of total mass and charge Q, and containing a radially directed macroscopic string. We find that the effective string mass m satisfies the inequality m 2 ≥ 0, signifying stability, provided that , which corresponds to the Reissner-Nordström black hole. The case of marginal string stability, m 2 = 0, is the extremal solution , which was shown by Gibbons and Hull to be supersymmetric, and has a marginal horizon. If , the horizon disappears, m 2 < 0, and the string becomes unstable.

  11. Forecasting geomagnetic activity at monthly and annual horizons: Time series models

    NASA Astrophysics Data System (ADS)

    Reikard, Gordon

    2015-10-01

    Most of the existing work on forecasting geomagnetic activity has been over short intervals, on the order of hours or days. However, it is also of interest to predict over longer horizons, ranging from months to years. Forecasting tests are run for the Aa index, which begins in 1868 and provides the longest continuous records of geomagnetic activity. This series is challenging to forecast. While it exhibits cycles at 11-22 years, the amplitude and period of the cycles varies over time. There is also evidence of discontinuous trending: the slope and direction of the trend change repeatedly. Further, at the monthly resolution, the data exhibits nonlinear variability, with intermittent large outliers. Several types of models are tested: regressions, neural networks, a frequency domain algorithm, and combined models. Forecasting tests are run at horizons of 1-11 years using the annual data, and 1-12 months using the monthly data. At the 1-year horizon, the mean errors are in the range of 13-17 percent while the median errors are in the range of 10-14 percent. The accuracy of the models deteriorates at longer horizons. At 5 years, the mean errors lie in the range of 21-23 percent, and at 11 years, 23-25 percent. At the 1 year horizon, the most accurate forecast is achieved by a combined model, but over longer horizons (2-11 years), the neural net dominates. At the monthly resolution, the mean errors are in the range of 17-19 percent at 1 month, while the median errors lie in a range of 14-17 percent. The mean error increases to 23-24 percent at 5 months, and 25 percent at 12 months. A model combining frequency and time domain methods is marginally better than regressions and neural networks alone, up to 11 months. The main conclusion is that geomagnetic activity can only be predicted to within a limited threshold of accuracy, over a given range of horizons. This is consistent with the finding of irregular trends and cycles in the annual data and nonlinear variability in

  12. Conversations: 20 Years in American Education.

    ERIC Educational Resources Information Center

    Green, Joslyn

    Eleven influential individuals who have brought breadth of vision to their work in education answer questions and give comments on the next 20 years of education by looking back on the past 20 years. The panelists are: Alonzo Crim, superintendent of schools in Atlanta, Georgia; Russell Edgerton, president of the American Association for Higher…

  13. Continuous-Time Mean-Variance Portfolio Selection with Random Horizon

    SciTech Connect

    Yu, Zhiyong

    2013-12-15

    This paper examines the continuous-time mean-variance optimal portfolio selection problem with random market parameters and random time horizon. Treating this problem as a linearly constrained stochastic linear-quadratic optimal control problem, I explicitly derive the efficient portfolios and efficient frontier in closed forms based on the solutions of two backward stochastic differential equations. Some related issues such as a minimum variance portfolio and a mutual fund theorem are also addressed. All the results are markedly different from those in the problem with deterministic exit time. A key part of my analysis involves proving the global solvability of a stochastic Riccati equation, which is interesting in its own right.

  14. HORIZON SENSING

    SciTech Connect

    Larry G. Stolarczyk, Sc.D.

    2002-07-31

    Real-time horizon sensing (HS) on continuous mining (CM) machines is becoming an industry tool. Installation and testing of production-grade HS systems has been ongoing this quarter at Oxbow Mining Company, Monterey Coal Company (EXXON), FMC Trona, Twentymile Coal Company (RAG America), and SASOL Coal. Detailed monitoring of system function, user experience, and mining benefits is ongoing. All horizon sensor components have finished MSHA (United States) and IEC (International) certification.

  15. Chert horizons as time-stratigraphic markers in Ordovician and Silurian of eastern Great Basin

    SciTech Connect

    Cameron, G.J.

    1986-08-01

    Data from numerous measured sections show that distinct chert horizons occur at or near the same stratigraphic intervals in a number of Ordovician and Silurian dolomite sequences in the eastern Great basin of Nevada and Utah. In many cases a shallow-water origin for the chert is inferred because of silicified shelfal fauna and lack of deeper water indicators. The cherty intervals appear to transgress across environmentally controlled lithologic boundaries. This fact, coupled with the regional extent of the chert, suggests that these intervals can be used as time-stratigraphic marker horizons. This concept is useful in assessing the degree of stratigraphic thinning of Upper Silurian strata along a regional unconformity. Although chert is almost ubiquitously present in certain stratigraphic intervals, the abundance of chert-bearing horizons within an individual section varies. By contouring the abundance of chert-bearing intervals within the Silurian system, a well-defined pattern is documented that increases in abundance to the northeast toward the northwestern corner of Utah. The ratio of chert to dolomite within the intervals increases correspondingly. It is suggested that the chert is the result of silica supersaturation from the settling of wind-blow volcanic ash on the Silurian epicontinental sea. The distribution of the chert was largely a function of paleowind currents from an easterly or northerly active volcanic source area.

  16. Mean-Variance Hedging on Uncertain Time Horizon in a Market with a Jump

    SciTech Connect

    Kharroubi, Idris; Lim, Thomas; Ngoupeyou, Armand

    2013-12-15

    In this work, we study the problem of mean-variance hedging with a random horizon T∧τ, where T is a deterministic constant and τ is a jump time of the underlying asset price process. We first formulate this problem as a stochastic control problem and relate it to a system of BSDEs with a jump. We then provide a verification theorem which gives the optimal strategy for the mean-variance hedging using the solution of the previous system of BSDEs. Finally, we prove that this system of BSDEs admits a solution via a decomposition approach coming from filtration enlargement theory.

  17. Optimal Consumption in a Brownian Model with Absorption and Finite Time Horizon

    SciTech Connect

    Grandits, Peter

    2013-04-15

    We construct {epsilon}-optimal strategies for the following control problem: Maximize E[{integral}{sub [0,{tau})}e{sup -{beta}s} dC{sub s}+e{sup -{beta}{tau}}X{sub {tau}}] , where X{sub t}=x+{mu}t+{sigma}W{sub t}-C{sub t}, {tau}{identical_to}inf{l_brace}t>0|X{sub t}=0{r_brace} Logical-And T, T>0 is a fixed finite time horizon, W{sub t} is standard Brownian motion, {mu}, {sigma} are constants, and C{sub t} describes accumulated consumption until time t. It is shown that {epsilon}-optimal strategies are given by barrier strategies with time-dependent barriers.

  18. A receding horizon scheme for discrete-time polytopic linear parameter varying systems in networked architectures

    NASA Astrophysics Data System (ADS)

    Franzè, Giuseppe; Lucia, Walter; Tedesco, Francesco

    2014-12-01

    This paper proposes a Model Predictive Control (MPC) strategy to address regulation problems for constrained polytopic Linear Parameter Varying (LPV) systems subject to input and state constraints in which both plant measurements and command signals in the loop are sent through communication channels subject to time-varying delays (Networked Control System (NCS)). The results here proposed represent a significant extension to the LPV framework of a recent Receding Horizon Control (RHC) scheme developed for the so-called robust case. By exploiting the parameter availability, the pre-computed sequences of one- step controllable sets inner approximations are less conservative than the robust counterpart. The resulting framework guarantees asymptotic stability and constraints fulfilment regardless of plant uncertainties and time-delay occurrences. Finally, experimental results on a laboratory two-tank test-bed show the effectiveness of the proposed approach.

  19. MARKOV: A methodology for the solution of infinite time horizon MARKOV decision processes

    USGS Publications Warehouse

    Williams, B.K.

    1988-01-01

    Algorithms are described for determining optimal policies for finite state, finite action, infinite discrete time horizon Markov decision processes. Both value-improvement and policy-improvement techniques are used in the algorithms. Computing procedures are also described. The algorithms are appropriate for processes that are either finite or infinite, deterministic or stochastic, discounted or undiscounted, in any meaningful combination of these features. Computing procedures are described in terms of initial data processing, bound improvements, process reduction, and testing and solution. Application of the methodology is illustrated with an example involving natural resource management. Management implications of certain hypothesized relationships between mallard survival and harvest rates are addressed by applying the optimality procedures to mallard population models.

  20. Pluto's Atmosphere at the Time of the New Horizons Flyby from the 29-JUN-2015 Occultation

    NASA Astrophysics Data System (ADS)

    Young, E.; Skrutskie, M.; Wasserman, L.; Howell, R.; Young, L.; Olkin, C.; Buie, M.

    2015-10-01

    Pluto is expected to occult a star on 29-JUN-2015, only two weeks before the scheduled New Horizons flyby on Pluto on 14-JUL-2015. This occultation should be remarkable for several reasons in addition to its synergy with the spacecraft observations. First, the occulted star is by far the brightest ever to be observed in a Pluto occultation: its V-mag is 12.10 ± 0.03, about ten times brighter than Pluto itself. We are deploying a wide array of telescopes to obtain quality lightcurves at 10 Hz, sufficient to resolve vertical atmospheric structure (e.g., gravity waves) at the 2.5-km scale over a range of radii from about 1195 to 1300 km. Second, we plan to obtain lighcurves in infrared wavelengths near 1.7 μm, where the star's H-mag (about 11) is bright enough to provide useful signal-to-noise ratios, albeit at slower cadences near 1 Hz (about two points per scale height). The combination of simultaneous IR and visible wavelength lightcurves should address the decades-old question: is there haze in Pluto's atmosphere, and if so, what is its opacity? New Horizons should image haze layers in reflected light as the occultation quantifies haze extinction in transmitted light: the combination could potentially let us solve for haze phase functions. Third, the current predicted shadow path is centered over much of New Zealand. We plan to deploy three portable telescopes in New Zealand to locations that are candidates for observing central flashes. If successful, these lightcurves can tell us (a) the oblateness of Pluto's atmosphere and (b) the detailed density gradient profile at radii near 1215 km, which (in turn) is a function of trace abundances of CO and CH4 a few tens of km above Pluto's surface. We will report on lightcurves obtained on 29-JUN- 2015, the column abundance of Pluto's atmosphere just two weeks before the New Horizons flyby, the detection (or not) of haze, and - if central flashes are obtained - the oblateness of Pluto's atmosphere.

  1. HORIZON SENSING

    SciTech Connect

    Larry G. Stolarczyk

    2003-03-18

    program began development in 1998 and experienced three major design phases. The final version, termed HS-3, was commissioned in 2000 with the assistance of the DOE-Mining Industry of the Future program, commercialized in 2002, and has been used 14 times in 12 different mines within the United States. The Horizon Sensor has applications in both underground and surface mining operations. This technology is primarily used in the coal industry, but is also used to mine trona and potash. All horizon sensor components have Mine Safety and Health Administration (MSHA) (United States) and IEC (International) certification. Horizon Sensing saves energy by maximizing cutting efficiency, cutting only desired material. This desired material is cleaner fuel, therefore reducing pollutants to the atmosphere when burned and burning more efficiently. Extracting only desired material increases productivity by reducing or eliminating the cleaning step after extraction. Additionally, this technology allows for deeper mining, resulting in more material gained from one location. The remote sensing tool allows workers to operate the machinery away from the hazards of cutting coal, including noise, breathing dust and gases, and coal and rock splintering and outbursts. The HS program has primarily revolved around the development of the technology. However, the end goal of the program has always been the commercialization of the technology and only within the last 2 years of the program has this goal been realized. Real-time horizon sensing on mining machines is becoming an industry tool. Detailed monitoring of system function, user experience, and mining benefits is ongoing.

  2. ''Illusion of control'' in Time-Horizon Minority and Parrondo Games

    NASA Astrophysics Data System (ADS)

    Satinover, J. B.; Sornette, D.

    2007-12-01

    Human beings like to believe they are in control of their destiny. This ubiquitous trait seems to increase motivation and persistence, and is probably evolutionarily adaptive [J.D. Taylor, S.E. Brown, Psych. Bull. 103, 193 (1988); A. Bandura, Self-efficacy: the exercise of control (WH Freeman, New York, 1997)]. But how good really is our ability to control? How successful is our track record in these areas? There is little understanding of when and under what circumstances we may over-estimate [E. Langer, J. Pers. Soc. Psych. 7, 185 (1975)] or even lose our ability to control and optimize outcomes, especially when they are the result of aggregations of individual optimization processes. Here, we demonstrate analytically using the theory of Markov Chains and by numerical simulations in two classes of games, the Time-Horizon Minority Game [M.L. Hart, P. Jefferies, N.F. Johnson, Phys. A 311, 275 (2002)] and the Parrondo Game [J.M.R. Parrondo, G.P. Harmer, D. Abbott, Phys. Rev. Lett. 85, 5226 (2000); J.M.R. Parrondo, How to cheat a bad mathematician (ISI, Italy, 1996)], that agents who optimize their strategy based on past information may actually perform worse than non-optimizing agents. In other words, low-entropy (more informative) strategies under-perform high-entropy (or random) strategies. This provides a precise definition of the “illusion of control” in certain set-ups a priori defined to emphasize the importance of optimization.

  3. Human psychoneuroimmunology: 20 years of discovery.

    PubMed

    Irwin, Michael R

    2008-02-01

    An important component of psychoneuroimmunology research is to reveal the myriad ways that behaviors and health are inter-related, with a focus on the immunological mechanisms that underlie these interactions. Research in human psychoneuroimmunology has shown that immunoregulatory processes are an integral part of a complex network of adaptive responses. As such, this review provides a perspective from our laboratory over the last 20 years to define the inter-relationships between behavior and immunity; to identify the hypothalamic pituitary adrenal (HPA) and autonomic mechanisms that link the central nervous system and immune responses; to examine the clinical implications of immune alterations during depression or life stress on inflammatory and infectious disease risk; and to explore the reciprocal role of immune mediators on behavior in humans.

  4. Psychology and Aging: The First 20 Years

    PubMed Central

    Zacks, Rose T.; Blanchard-Fields, Fredda; Haley, William E.

    2006-01-01

    This article provides a review of the first 20 years of Psychology and Aging, the American Psychological Association’s first and only scholarly journal devoted to the topic of aging. The authors briefly summarize its history, its contributions to the study of aging, and its broader status as a scholarly publication. One theme highlighted in our review is the diversity of content in the journal throughout its history. Another is the strong impact that articles published in the journal have had on both basic and applied topics in aging. Efforts to encompass the breadth of topics and methodologies in aging research while retaining excellent quality remain the exciting but essential challenge for Psychology and Aging. PMID:16594786

  5. Psychology and Aging: the first 20 years.

    PubMed

    Zacks, Rose T; Blanchard-Fields, Fredda; Haley, William E

    2006-03-01

    This article provides a review of the first 20 years of Psychology and Aging, the American Psychological Association's first and only scholarly journal devoted to the topic of aging. The authors briefly summarize its history, its contributions to the study of aging, and its broader status as a scholarly publication. One theme highlighted in our review is the diversity of content in the journal throughout its history. Another is the strong impact that articles published in the journal have had on both basic and applied topics in aging. Efforts to encompass the breadth of topics and methodologies in aging research while retaining excellent quality remain the exciting but essential challenge for Psychology and Aging.

  6. The Forties field: 20 years young

    SciTech Connect

    Brand, P.J.; Clyne, P.A.; Kirkwood, F.G.; Williams, P.W.

    1996-04-01

    In Oct. 1970, BP`s semisubmersible drilling rig SeaQuest struck oil in Upper Paleocene (Tertiary) sandstones of U.K. Continental Shelf Block 21/10. Four appraisal wells drilled in 1970 and 1971 delineated a large oil reservoir at a depth of 7,000 ft., covering an area of 36 sq miles. The maximum thickness of the oil-bearing sandstone was estimated at 614 ft. Reserves were calculated to be 1,800 MMSTB from an oil in place (OIP) of 4,600 MMSTB, and production was projected to continue until Year 2000. In 1971, Shell/Esso drilled a successful well, Well 22/6-1, that demonstrated the southeastern extension of the field into Block 22/6. The field is a four-way-dip-closed anticline that overlies the Forties-Montrose Ridge and is close to the junction of the Central, South Viking, and Witch Ground grabens. The reservoir occurs in thick Upper Paleocene sandstones deposited as a sand-rich submarine fan sequence. This paper describes how the development of the Forties field has evolved over the past 20 years, the current issues and activities, and the direction for the future.

  7. 75 FR 37712 - Temporary Suspension of Certain Oil Spill Response Time Requirements To Support Deepwater Horizon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-30

    ... and sinking of the Mobile Offshore Drilling Unit ``Deepwater Horizon'' on April 20, 2010, causing an... (73 FR 3316). II. Abbreviations AMPD Average Most Probable Discharge CEQ Council on Environmental... Environmental Protection Agency FOSC Federal On-Scene Coordinator FR Federal Register MMPD Maximum Most...

  8. Calcium-sensing receptor 20 years later

    PubMed Central

    Alfadda, Tariq I.; Saleh, Ahmad M. A.; Houillier, Pascal

    2014-01-01

    The calcium-sensing receptor (CaSR) has played an important role as a target in the treatment of a variety of disease states over the past 20 plus years. In this review, we give an overview of the receptor at the cellular level and then provide details as to how this receptor has been targeted to modulate cellular ion transport mechanisms. As a member of the G protein-coupled receptor (GPCR) family, it has a high degree of homology with a variety of other members in this class, which could explain why this receptor has been identified in so many different tissues throughout the body. This diversity of locations sets it apart from other members of the family and may explain how the receptor interacts with so many different organ systems in the body to modulate the physiology and pathophysiology. The receptor is unique in that it has two large exofacial lobes that sit in the extracellular environment and sense changes in a wide variety of environmental cues including salinity, pH, amino acid concentration, and polyamines to name just a few. It is for this reason that there has been a great deal of research associated with normal receptor physiology over the past 20 years. With the ongoing research, in more recent years a focus on the pathophysiology has emerged and the effects of receptor mutations on cellular and organ physiology have been identified. We hope that this review will enhance and update the knowledge about the importance of this receptor and stimulate future potential investigations focused around this receptor in cellular, organ, and systemic physiology and pathophysiology. PMID:24871857

  9. Review: R28 retinal precursor cells: The first 20 years

    PubMed Central

    2014-01-01

    The R28 retinal precursor cell line was established 20 years ago, originating from a postnatal day 6 rat retinal culture immortalized with the 12S E1A (NP-040507) gene of the adenovirus in a replication-incompetent viral vector. Since that time, R28 cells have been characterized and used for a variety of in vitro and in vivo studies of retinal cell behavior, including differentiation, neuroprotection, cytotoxicity, and light stimulation, as well as retinal gene expression and neuronal function. While no cell culture is equivalent to the intact eye, R28 cells continue to provide an important experimental system for the study of many retinal processes. PMID:24644404

  10. Reflections on 20+ Years of ESD

    ERIC Educational Resources Information Center

    Hopkins, Charles

    2012-01-01

    As one of 12 members of the drafting committee of Agenda 21's Chapter 36, "Education, Public Awareness and Training", Charles Hopkins reflects on the process of working on the now-famous document. Although it was noncontroversial at the time, Chapter 36 spawned education for sustainable development when it was given to UNESCO to administer within…

  11. Czech Republic 20 years after Chernobyl accident.

    PubMed

    Rosina, Jozef; Kvasnák, Eugen; Suta, Daniel; Kostrhun, Tomás; Drábová, Dana

    2008-01-01

    The territory of the Czech Republic was contaminated as a result of the breakdown in the Chernobyl nuclear power plant in 1986. The Czech population received low doses of ionising radiation which, though it could not cause a deterministic impact, could have had stochastic effects expressed in the years following the accident. Twenty years after the accident is a long enough time to assess its stochastic effects, primarily tumours and genetic impairment. The moderate amount of radioactive fallout received by the Czech population in 1986 increased thyroid cancer in the following years; on the other hand, no obvious genetic impact was found.

  12. Global satellite composites - 20 years of evolution

    NASA Astrophysics Data System (ADS)

    Kohrs, Richard A.; Lazzara, Matthew A.; Robaidek, Jerrold O.; Santek, David A.; Knuth, Shelley L.

    2014-01-01

    For two decades, the University of Wisconsin Space Science and Engineering Center (SSEC) and the Antarctic Meteorological Research Center (AMRC) have been creating global, regional and hemispheric satellite composites. These composites have proven useful in research, operational forecasting, commercial applications and educational outreach. Using the Man computer Interactive Data System (McIDAS) software developed at SSEC, infrared window composites were created by combining Geostationary Operational Environmental Satellite (GOES), and polar orbiting data from the SSEC Data Center and polar data acquired at McMurdo and Palmer stations, Antarctica. Increased computer processing speed has allowed for more advanced algorithms to address the decision making process for co-located pixels. The algorithms have evolved from a simplistic maximum brightness temperature to those that account for distance from the sub-satellite point, parallax displacement, pixel time and resolution. The composites are the state-of-the-art means for merging/mosaicking satellite imagery.

  13. 20 Years of Improvements to GEOSAT Altimetry

    NASA Astrophysics Data System (ADS)

    Lillibridge, J.; Smith, W. H. F.; Sandwell, D.; Scharroo, R.; Lemoine, F.; Zelensky, N.

    2006-07-01

    The U.S. N avy GEO SAT mission provided the first long-term altimetr ic record for studies of ocean circu lation , mar ine grav ity /bathymetry and continen tal ice. The Geodetic Mission (G M) data were declassified by the Navy in 1995 and released by NOAA togeth er with the Ex act Rep eat Mission data in the 1997 JG M-3 Geophysical Data Records (GDRs). We have now comp leted a major upgrade of the G M data by reprocessing the origin al Sensor D ata Records (SDRs) and Wav eform Data Records (WD Rs) . Th is has allowed us to retrack all the over-ocean waveforms from the G M to improve measuremen ts of sea surface heigh t and its slope and th ereby produce better models of marin e gravity and bathymetry . A unique two-pass retracking algorithm is used to r educe th e noise in along-track sea surface slope, and to reduce th e correlation in errors betw een r ange and SWH from th e waveform f itting. The precise orbit deter min ation uses the full set of 45 Doppler TRAN ET tracking stations and is b ased on a GRA CE grav ity model. W ith improved corrections and retracking mar ine gr avity and bathymetry reso lution ar e improved, while the new pr ecise orbits y ield better estimates of sea lev el r ise from th e GEOSA T time period.

  14. Radium in man - 20 years later

    SciTech Connect

    Maletskos, C.J.

    1994-12-31

    In 1940, there was a need to set a standard for internal exposure to radium for the instrument industry that required luminous characters painted with radium paint. A committee was convened to review the existing information on the health effects of internal radium. Twenty-seven persons had been studied, seven with burdens of 0.5 {mu}g or less with no health effects and twenty with burdens of 1.2 {mu}g or more with health effects. The radium burden dividing the two groups was assumed at 1 {mu}g (an implied threshold), a safety factor of 10 was applied, and the internal radium standard was set at 0.1 {mu}g, a value that still stands today. Over the next five or six decades, about 2000 subjects were investigated, including many measurements on almost all the subjects. In the intervening years, several analyses of the data, available at each particular time, have been made with radical differences in interpretation.

  15. High energy particle colliders: past 20 years, next 20 years and beyond

    SciTech Connect

    Shiltsev, Vladimir D.; /Fermilab

    2012-04-01

    Particle colliders for high energy physics have been in the forefront of scientific discoveries for more than half a century. The accelerator technology of the collider has progressed immensely, while the beam energy, luminosity, facility size and the cost have grown by several orders of magnitude. The method of colliding beams has not fully exhausted its potential but its pace of progress has greatly slowed down. In this paper we very briefly review the method and the history of colliders, discuss in detail the developments over the past two decades and the directions of the R and D toward near future colliders which are currently being explored. Finally, we make an attempt to look beyond the current horizon and outline the changes in the paradigm required for the next breakthroughs.

  16. HIGH-ENERGY PARTICLE COLLIDERS: PAST 20 YEARS, NEXT 20 YEARS, AND BEYOND

    SciTech Connect

    Shiltsev, V.

    2013-09-25

    Particle colliders for high-energy physics have been in the forefront of scientific discoveries for more than half a century. The accelerator technology of the colliders has progressed immensely, while the beam energy, luminosity, facility size, and cost have grown by several orders of magnitude. The method of colliding beams has not fully exhausted its potential but has slowed down considerably in its progress. This paper briefly reviews the colliding beam method and the history of colliders, discusses the development of the method over the last two decades in detail, and examines near-term collider projects that are currently under development. The paper concludes with an attempt to look beyond the current horizon and to find what paradigm changes are necessary

  17. Emergence of time-horizon invariant correlation structure in financial returns by subtraction of the market mode

    NASA Astrophysics Data System (ADS)

    Borghesi, Christian; Marsili, Matteo; Miccichè, Salvatore

    2007-08-01

    We investigate the emergence of a structure in the correlation matrix of assets’ returns as the time horizon over which returns are computed increases from the minutes to the daily scale. We analyze data from different stock markets (New York, Paris, London, Milano) and with different methods. In addition to the usual correlations, we also analyze those obtained by subtracting the dynamics of the “center of mass” (i.e., the market mode). We find that when the center of mass is not removed the structure emerges, as the time horizon increases, from splitting a single large cluster into smaller ones. By contrast, when the market mode is removed the structure of correlations observed at the daily scale is already well defined at very high frequency ( 5min in the New York Stock Exchange). Moreover, this structure accounts for 80% of the classification of stocks in economic sectors. Similar results, though less sharp, are found for the other markets. We also find that the structure of correlations in the overnight returns is markedly different from that of intraday activity.

  18. The State of Pluto's Bulk Atmosphere at the Time of the New Horizons Encounter

    NASA Astrophysics Data System (ADS)

    Resnick, Aaron C.; Barry, T.; Buie, M. W.; Carriazo, C. Y.; Cole, A.; Gault, D.; Giles, B.; Giles, D.; Hartig, K.; Hill, K.; Howell, R. R.; Hudson, G.; Loader, B.; Mackie, J.; Nelson, M.; Olkin, C.; Register, J.; Rodgers, T.; Sicardy, B.; Skrutskie, M.; Verbiscer, A.; Wasserman, L.; Watson, C.; Young, E.; Young, L.; Zalucha, A.

    2015-11-01

    On 29-JUL-2015, our team - plus many critical amateur astronomers - observed a stellar occultation by Pluto from sites in Australia and New Zealand. This event was remarkable for two reasons: it preceded the New Horizons flyby of Pluto by just two weeks, and the occulted star was about 10x brighter than Pluto itself, by far the brightest Pluto occultation event observed to date. The separation of ground sites spanned nearly 900 km with respect to the central chord, allowing a good geometric solution for the shadow path. The lightcurves show some inflection points and broad "fangs" that are characteristic of perturbations in the temperature profile. Preliminary fits show that the temperature profile derived from a 2006 occultation (Young et al. 2008) reproduces the 29-JUN-2015 lightcurves well. Assuming a surface radius of 1187 km for Pluto, we find that the surface pressure is 18 +/- 3 µbar. This pressure indicates that Pluto's surface has not yet started to cool down, despite a decrease in absorbed solar flux of more than 17% since perihelion in 1988. A surface pressure of 18 µbar would correspond to a nitrogen ice surface temperature of 38.0 K.References:Young, E.F., et al. "Vertical Structure in Pluto's Atmosphere from the 2006 June 12 Stellar Occultation," AJ 136 1757-1769 (2008)

  19. Water Stress on U.S. Power Production at Decadal Time Horizons

    NASA Astrophysics Data System (ADS)

    Ganguli, P.; Kumar, D.; Yun, J.; Short, G.; Klausner, J.; Ganguly, A. R.

    2014-12-01

    Thermoelectric power production at risk, owing to current and projected water scarcity and rising stream temperatures, is assessed for the continental United States (US) at decadal scales. Regional water scarcity is driven by climate variability and change, as well as by multi-sector water demand. While a planning horizon of zero to about thirty years is occasionally prescribed by stakeholders, the challenges to risk assessment at these scales include the difficulty in delineating decadal climate trends from intrinsic natural or multiple model variability. Current generation global climate or earth system models are not credible at the spatial resolutions of power plants, especially for surface water quantity and stream temperatures, which further exacerbates the assessment challenge. Population changes, which are anyway difficult to project, cannot serve as adequate proxies for changes in the water demand across sectors. The hypothesis that robust assessments of power production at risks are possible, despite the uncertainties, has been examined as a proof of concept. An approach is presented for delineating water scarcity and temperature from climate models, observations and population storylines, as well as for assessing power production at risk by examining geospatial correlations of power plant locations within regions where the usable water supply for energy production happens to be scarcer and warmer. Acknowledgment: Funding provided by US DOE's ARPA-E through Award DE-AR0000374.

  20. The Challenges in Metadata Management: 20+ Years of ESO Data

    NASA Astrophysics Data System (ADS)

    Vera, I.; Da Rocha, C.; Dobrzycki, A.; Micol, A.; Vuong, M.

    2015-09-01

    The European Southern Observatory Science Archive Facility has been in operations for more than 20 years. It contains data produced by ESO telescopes as well as the metadata needed for characterizing and distributing those data. This metadata is used to build the different archive services provided by the Archive. Over these years, services have been added, modified or even decommissioned creating a cocktail of new, evolved and legacy data systems. The challenge for the Archive is to harmonize the differences of those data systems to provide the community with a homogeneous experience when using ESO data. In this paper, we present ESO experience in three particular challenging areas. First discussion is dedicated to the problem of metadata quality over the time, second discusses how to integrate obsolete data models on the current services and finally we will present the challenges of ever growing databases. We describe our experience dealing with those issues and the solutions adopted to mitigate them.

  1. Multicultural Counseling Competencies Research: A 20-Year Content Analysis

    ERIC Educational Resources Information Center

    Worthington, Roger L.; Soth-McNett, Angela M.; Moreno, Matthew V.

    2007-01-01

    The authors conducted a 20-year content analysis of the entire field of empirical research on the multicultural counseling competencies (D. W. Sue et al., 1982). They conducted an exhaustive search for empirical research articles using PsycINFO, as well as complete reviews of the past 20 years of several journals (e.g., Journal of Counseling…

  2. Adaptive dynamic programming for finite-horizon optimal control of discrete-time nonlinear systems with ε-error bound.

    PubMed

    Wang, Fei-Yue; Jin, Ning; Liu, Derong; Wei, Qinglai

    2011-01-01

    In this paper, we study the finite-horizon optimal control problem for discrete-time nonlinear systems using the adaptive dynamic programming (ADP) approach. The idea is to use an iterative ADP algorithm to obtain the optimal control law which makes the performance index function close to the greatest lower bound of all performance indices within an ε-error bound. The optimal number of control steps can also be obtained by the proposed ADP algorithms. A convergence analysis of the proposed ADP algorithms in terms of performance index function and control policy is made. In order to facilitate the implementation of the iterative ADP algorithms, neural networks are used for approximating the performance index function, computing the optimal control policy, and modeling the nonlinear system. Finally, two simulation examples are employed to illustrate the applicability of the proposed method. PMID:20876014

  3. Neural network-based finite-horizon optimal control of uncertain affine nonlinear discrete-time systems.

    PubMed

    Zhao, Qiming; Xu, Hao; Jagannathan, Sarangapani

    2015-03-01

    In this paper, the finite-horizon optimal control design for nonlinear discrete-time systems in affine form is presented. In contrast with the traditional approximate dynamic programming methodology, which requires at least partial knowledge of the system dynamics, in this paper, the complete system dynamics are relaxed utilizing a neural network (NN)-based identifier to learn the control coefficient matrix. The identifier is then used together with the actor-critic-based scheme to learn the time-varying solution, referred to as the value function, of the Hamilton-Jacobi-Bellman (HJB) equation in an online and forward-in-time manner. Since the solution of HJB is time-varying, NNs with constant weights and time-varying activation functions are considered. To properly satisfy the terminal constraint, an additional error term is incorporated in the novel update law such that the terminal constraint error is also minimized over time. Policy and/or value iterations are not needed and the NN weights are updated once a sampling instant. The uniform ultimate boundedness of the closed-loop system is verified by standard Lyapunov stability theory under nonautonomous analysis. Numerical examples are provided to illustrate the effectiveness of the proposed method. PMID:25720005

  4. Water survival: 20 years Canadian Forces aircrew experience.

    PubMed

    Brooks, C J; Rowe, K W

    1984-01-01

    A 20 year review of Canadian Forces (CF) aircrew ejection/ditching, survival/rescue times and injury patterns in salt and fresh water is presented. Of the 595 A, B, and C category accidents which have been reviewed (1962-1982), 37 were water-entry. Of the 116 crew which were involved, 38 died (4 in fresh water). The Sea King helicopter is most at risk from sea water immersion, and the single-engine Otter has been the most vulnerable to fresh water immersion. A water immersion can be expected approximately once every 170,000 h of total flying time. In 92% of cases, the crew had less than 1 min warning that immersion was imminent and in 78% had less than 15 s to make a practical response. There were two clinical cases of hypothermia. In the absence of injuries, aircrew trained in water survival, qualified on the Dilbert Dunker, and who are strong swimmers or sports divers, have a better chance to survival. Time to rescue in all cases was under 3 h, and in 16 out of 24 cases crew members were rescued in under 15 min.

  5. The next 20 years: how customer and workforce attitudes will evolve.

    PubMed

    Howe, Neil; Strauss, William

    2007-01-01

    Business projects with very long time horizons--such as those involving product R&D, workplace design, and total compensation planning--have to contend with a crucial question: What will be the needs, demands, and desires of consumers and employees decades from now? If you think the answer is "Just more of the same," you're in for a surprise. Howe and Strauss, the authors of Generations, The Fourth Turning, Millennials Rising, and other books, have studied the differences among generations for some 30 years. Their extensive research has revealed a fascinating pattern--one so strong that it supports a measure of predictability. On the basis of historical precedent, they say, we can foresee how the generations that are alive today will think and act in decades to come. Three of those generations will still be vital forces in American society 20 years from now: Boomers, Generation X, and Millennials. Their attitudes and behaviors will have profound effects on the economy, the workplace, and social institutions in general. For example, as aging Boomers eschew high-tech medicine in favor of holistic self-care, natural foods, and mind-body healing techniques, some hospitals are opening new wings featuring alternative medicine and spiritual counseling. Gen Xers, having grown up in an era of failing schools and marriages, will remain alienated, disaffected, and pragmatic as they enter midlife. Already the greatest entrepreneurial generation in U.S. history, they will be highly effective at pushing innovation, efficiency, and mass customization. In contrast, young adult Millennials will favor teamwork, close family relationships, job security, and a bland popular culture. Their unprecedented digital empowerment and talent for organizing will create a political powerhouse and may even revitalize the union movement. PMID:17642125

  6. The next 20 years: how customer and workforce attitudes will evolve.

    PubMed

    Howe, Neil; Strauss, William

    2007-01-01

    Business projects with very long time horizons--such as those involving product R&D, workplace design, and total compensation planning--have to contend with a crucial question: What will be the needs, demands, and desires of consumers and employees decades from now? If you think the answer is "Just more of the same," you're in for a surprise. Howe and Strauss, the authors of Generations, The Fourth Turning, Millennials Rising, and other books, have studied the differences among generations for some 30 years. Their extensive research has revealed a fascinating pattern--one so strong that it supports a measure of predictability. On the basis of historical precedent, they say, we can foresee how the generations that are alive today will think and act in decades to come. Three of those generations will still be vital forces in American society 20 years from now: Boomers, Generation X, and Millennials. Their attitudes and behaviors will have profound effects on the economy, the workplace, and social institutions in general. For example, as aging Boomers eschew high-tech medicine in favor of holistic self-care, natural foods, and mind-body healing techniques, some hospitals are opening new wings featuring alternative medicine and spiritual counseling. Gen Xers, having grown up in an era of failing schools and marriages, will remain alienated, disaffected, and pragmatic as they enter midlife. Already the greatest entrepreneurial generation in U.S. history, they will be highly effective at pushing innovation, efficiency, and mass customization. In contrast, young adult Millennials will favor teamwork, close family relationships, job security, and a bland popular culture. Their unprecedented digital empowerment and talent for organizing will create a political powerhouse and may even revitalize the union movement.

  7. Average American 15 Pounds Heavier Than 20 Years Ago

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_160233.html Average American 15 Pounds Heavier Than 20 Years Ago ... since the late 1980s and early 1990s, the average American has put on 15 or more additional ...

  8. Time horizons and substance use among African American youths living in disadvantaged urban areas.

    PubMed

    Cheong, JeeWon; Tucker, Jalie A; Simpson, Cathy A; Chandler, Susan D

    2014-04-01

    Transitioning from adolescence to full-fledged adulthood is often challenging, and young people who live in disadvantaged urban neighborhoods face additional obstacles and experience disproportionately higher negative outcomes, including substance abuse and related risk behaviors. This study investigated whether substance use among African Americans ages 15 to 25 (M=18.86 years) living in such areas was related to present-dominated time perspectives and higher delay discounting. Participants (N=344, 110 males, 234 females) living in Deep South disadvantaged urban neighborhoods were recruited using Respondent Driven Sampling, an improved peer-referral sampling method suitable for accessing this hard-to-reach target group. Structured field interviews assessed alcohol, tobacco, and illicit drug use and risk/protective factors, including time perspectives (Zimbardo Time Perspective Inventory [ZTPI]) and behavioral impulsivity (delay discounting task). As predicted, substance use was positively related to a greater ZTPI orientation toward present pleasure and a lower tendency to plan and achieve future goals. Although the sample as a whole showed high discounting of delayed rewards, discount rates did not predict substance use. The findings suggest that interventions to lengthen time perspectives and promote enriched views of future possible selves may prevent and reduce substance use among disadvantaged youths. Discontinuities among the discounting and time perspective variables in relation to substance use merit further investigation.

  9. Time horizons and substance use among African American youths living in disadvantaged urban areas.

    PubMed

    Cheong, JeeWon; Tucker, Jalie A; Simpson, Cathy A; Chandler, Susan D

    2014-04-01

    Transitioning from adolescence to full-fledged adulthood is often challenging, and young people who live in disadvantaged urban neighborhoods face additional obstacles and experience disproportionately higher negative outcomes, including substance abuse and related risk behaviors. This study investigated whether substance use among African Americans ages 15 to 25 (M=18.86 years) living in such areas was related to present-dominated time perspectives and higher delay discounting. Participants (N=344, 110 males, 234 females) living in Deep South disadvantaged urban neighborhoods were recruited using Respondent Driven Sampling, an improved peer-referral sampling method suitable for accessing this hard-to-reach target group. Structured field interviews assessed alcohol, tobacco, and illicit drug use and risk/protective factors, including time perspectives (Zimbardo Time Perspective Inventory [ZTPI]) and behavioral impulsivity (delay discounting task). As predicted, substance use was positively related to a greater ZTPI orientation toward present pleasure and a lower tendency to plan and achieve future goals. Although the sample as a whole showed high discounting of delayed rewards, discount rates did not predict substance use. The findings suggest that interventions to lengthen time perspectives and promote enriched views of future possible selves may prevent and reduce substance use among disadvantaged youths. Discontinuities among the discounting and time perspective variables in relation to substance use merit further investigation. PMID:24531637

  10. Impact of curvature divergences on physical observers in a wormhole space-time with horizons

    NASA Astrophysics Data System (ADS)

    Olmo, Gonzalo J.; Rubiera-Garcia, D.; Sanchez-Puente, A.

    2016-06-01

    The impact of curvature divergences on physical observers in a black hole space-time, which, nonetheless, is geodesically complete is investigated. This space-time is an exact solution of certain extensions of general relativity coupled to Maxwell’s electrodynamics and, roughly speaking, consists of two Reissner-Nordström (or Schwarzschild or Minkowski) geometries connected by a spherical wormhole near the center. We find that, despite the existence of infinite tidal forces, causal contact is never lost among the elements making up the observer. This suggests that curvature divergences may not be as pathological as traditionally thought.

  11. The odontogenic keratocyst: a 20-year clinicopathologic review.

    PubMed

    Meara, J G; Shah, S; Li, K K; Cunningham, M J

    1998-02-01

    The odontogenic keratocyst (OKC) is a jaw cyst with a proclivity for local invasion and recurrence. This 20-year retrospective study was conducted to evaluate methods of treatment and recurrence rates. Forty-nine patients were identified with an average age at presentation of 39.5 years. The molar region of either the mandible or maxilla was the principal primary location; the maxillary antrum was also a common site. The majority of cysts were unilocular and associated with adjacent dentition. Initial therapy was typically enucleation with or without extraction of associated teeth; seven cases of recurrent or second primary odontogenic keratocysts required more extensive surgery. Follow-up ranged from 1 to 15 years with an average duration of 4.3 years. The overall recurrence rate was 35%, and the average time to recurrence 4 years. A recurrence rate of 60% was documented for patients with basal cell nevus syndrome or a family history thereof. Long-term follow-up is necessary following initial OKC treatment. The high rate of recurrence in patients with documented or suspected basal cell nevus syndrome suggests the need for more aggressive initial surgical management in this selected patient population.

  12. Juvenile angiofibroma: the lessons of 20 years of modern imaging.

    PubMed

    Lloyd, G; Howard, D; Phelps, P; Cheesman, A

    1999-02-01

    Seventy-two patients with juvenile angiofibroma have been investigated by computerized tomography (CT) and/or magnetic resonance imaging (MRI) over a period of 20 years. The evidence from these studies indicates that angiofibroma takes origin in the pterygo-palatine fossa at the aperture of the pterygoid (vidian) canal. An important extension of the tumour is posteriorly along the pterygoid canal with invasion of the cancellous bone of the pterygoid base, and greater wing of the sphenoid (60 per cent of patients). Distinctive features of angiofibroma are the high recurrence rate, and the rapidity with which many tumours recur. It is postulated that the principal determinant of recurrence is a high tumour growth rate at the time of surgery coupled with incomplete surgical excision. The inability to remove the tumour in toto is principally due to deep invasion of the sphenoid, as described above. In this series 93 per cent of recurrences occurred with this type of tumour extension. A contributory cause in these patients is the use of pre-operative embolization. The treatment implications of these findings are examined.

  13. Autonomous real-time adaptive management of soil salinity using a receding horizon control algorithm: a pilot-scale demonstration.

    PubMed

    Park, Yeonjeong; Harmon, Thomas C

    2011-10-01

    Soil salinization is a potentially negative side effect of irrigation with reclaimed water. While optimization schemes have been applied to soil salinity control, these have typically failed to take advantage of real-time sensor feedback. This study incorporates current soil observation technologies into the optimal feedback-control scheme known as Receding Horizon Control (RHC) to enable successful autonomous control of soil salinization. RHC uses real-time sensor measurements, physically-based state prediction models, and optimization algorithms to drive field conditions to a desired environmental state by manipulating application rate or irrigation duration/frequency. A simulation model including the Richards equation coupled to energy and solute transport equations is employed as a state estimator. Vertical multi-sensor arrays installed in the soil provide initial conditions and continuous feedback to the control scheme. An optimization algorithm determines the optimal irrigation rate or frequency subject to imposed constraints protective of soil salinization. A small-scale field test demonstrates that the RHC scheme is capable of autonomously maintaining specified salt levels at a prescribed soil depth. This finding suggests that, given an adequately structured and trained simulation model, sensor networks, and optimization algorithms can be integrated using RHC to autonomously achieve water reuse and agricultural objectives while managing soil salinization.

  14. 1.3 mm WAVELENGTH VLBI OF SAGITTARIUS A*: DETECTION OF TIME-VARIABLE EMISSION ON EVENT HORIZON SCALES

    SciTech Connect

    Fish, Vincent L.; Doeleman, Sheperd S.; Beaudoin, Christopher; Bolin, David E.; Rogers, Alan E. E.; Blundell, Ray; Gurwell, Mark A.; Moran, James M.; Primiani, Rurik; Bower, Geoffrey C.; Plambeck, Richard; Chamberlin, Richard; Freund, Robert; Friberg, Per; Honma, Mareki; Oyama, Tomoaki; Inoue, Makoto; Krichbaum, Thomas P.; Lamb, James; Marrone, Daniel P.

    2011-02-01

    Sagittarius A*, the {approx}4 x 10{sup 6} M{sub sun} black hole candidate at the Galactic center, can be studied on Schwarzschild radius scales with (sub)millimeter wavelength very long baseline interferometry (VLBI). We report on 1.3 mm wavelength observations of Sgr A* using a VLBI array consisting of the JCMT on Mauna Kea, the Arizona Radio Observatory's Submillimeter Telescope on Mt. Graham in Arizona, and two telescopes of the CARMA array at Cedar Flat in California. Both Sgr A* and the quasar calibrator 1924-292 were observed over three consecutive nights, and both sources were clearly detected on all baselines. For the first time, we are able to extract 1.3 mm VLBI interferometer phase information on Sgr A* through measurement of closure phase on the triangle of baselines. On the third night of observing, the correlated flux density of Sgr A* on all VLBI baselines increased relative to the first two nights, providing strong evidence for time-variable change on scales of a few Schwarzschild radii. These results suggest that future VLBI observations with greater sensitivity and additional baselines will play a valuable role in determining the structure of emission near the event horizon of Sgr A*.

  15. The Glacier Peak Tephra: A Continental-Scale Latest Pleistocene Time Horizon

    NASA Astrophysics Data System (ADS)

    Pyne-O'Donnell, S.; Cwynar, L. C.; Vincent, J. H.; Spear, R.; Froese, D. G.

    2014-12-01

    The latest Pleistocene eruptions of Glacier Peak in the Cascade Range deposited a widespread set of tephras throughout much of western North America within a short time span where they serve as valuable marker layers for inter-site correlation and chronostratigraphical control. We report the detection of these tephras in microscopic form in three lakes along the Eastern Seaboard (Maine and Nova Scotia). These distinct distal lake layers occur as closely spaced couplets which retain the subtle geochemical variation that characterises the proximal Glacier Peak G and B layers. New radiocarbon dates for the tephras also closely corroborate the most recently revised proximal dates for the tephras (ca. 13,700 - 13,400 cal. yr B.P) which found that they are ca. 400 14C yr older than hitherto thought. Their presence this far eastward implies that their deposition spans the intervening continent (>4000 km) and adds to a developing distal tephrostratigraphical framework with applications to studies of latest Pleistocene deglaciation and environmental change, megafaunal extinction and archaeology.

  16. HORIZON SENSING (PROPOSAL NO.51)

    SciTech Connect

    Larry G. Stolarczyk

    2003-07-01

    Real-time horizon sensing on continuous mining machines is becoming an industry tool. Installation and testing of production-grade Horizon Sensor (HS) systems continued this quarter at Monterey Coal Company (ExxonMobil), Mountain Coal Company West Elk Mine (Arch), and Ohio Valley Coal Company (OVC). Monitoring of system function, user experience, and mining benefits is ongoing. All horizon sensor components have finished MSHA (U.S.) and IEC (International) certification.

  17. HORIZON SENSING (PROPOSAL NO.51)

    SciTech Connect

    Larry G. Stolarczyk

    2003-07-30

    Real-time horizon sensing on continuous mining (CM) machines is becoming an industry tool. Installation and testing of production-grade Horizon Sensor (HS) systems has been ongoing this quarter at Monterey Coal Company (ExxonMobil), Mountain Coal Company West Elk Mine (Arch), Deserado Mining Company (Blue Mountain Energy), and The Ohio Valley Coal Company (TOVCC). Monitoring of system function, user experience, and mining benefits is ongoing. All horizon sensor components have finished MSHA (U.S.) and IEC (International) certification.

  18. Environmental Volunteering and Health Outcomes over a 20-Year Period

    ERIC Educational Resources Information Center

    Pillemer, Karl; Fuller-Rowell, Thomas E.; Reid, M. C.; Wells, Nancy M.

    2010-01-01

    Purpose: This study tested the hypothesis that volunteering in environmental organizations in midlife is associated with greater physical activity and improved mental and physical health over a 20-year period. Design and Methods: The study used data from two waves (1974 and 1994) of the Alameda County Study, a longitudinal study of health and…

  19. Building-Based Budgeting and Decentralization: A 20 Year Perspective.

    ERIC Educational Resources Information Center

    Ilg, Timothy J.; Raisch, C. Daniel

    This paper examines the effects of site-based budgeting in education. It describes and presents a school-based budgetary decision-making model that was designed originally to shift the balance of power from the central office to the building level. The model has been refined and successfully utilized in one school district for 20 years, and its…

  20. The Rainbow Reading Programme: A Review 20 Years on

    ERIC Educational Resources Information Center

    Dobson, Emma

    2013-01-01

    It has been 20 years since the Rainbow Reading programme was developed and trialled by its New Zealand creator, Meryl-Lynn Pluck. Rainbow Reading is an audio-facilitated reading programme, and is based on the method of assisted repeated reading. The programme is designed to provide older students reading below their chronological age with the…

  1. Lavoisier Preempted Gay-Lussac by 20 Years!

    ERIC Educational Resources Information Center

    Laing, Michael

    1998-01-01

    Lavoisier showed that water was formed by chemical reaction between hydrogen and oxygen. In Lavoisier's "Traite Elementaire" of 1789, he states that the reaction to form water requires exactly two volumes of hydrogen gas to react completely with one volume of oxygen gas. This was 20 years before Gay-Lussac studied the reactions between different…

  2. Support-Staff Jobs Double in 20 Years, Outpacing Enrollment

    ERIC Educational Resources Information Center

    Brainard, Jeffrey; Fain, Paul; Masterson, Kathryn

    2009-01-01

    Colleges have added managers and support personnel at a steady, vigorous clip over the past 20 years, new research shows, far outpacing the growth in student enrollment and instructors. Support staff--like budget analysts, computer specialists, and loan counselors--nearly doubled from 1987 to 2007. Meanwhile, jobs for instructors increased by only…

  3. Adenomatoid odontogenic tumour in a 20-year-old woman

    PubMed Central

    Virupakshappa, Deepti; Rajashekhara, Bhari Sharanesha; Manjunatha, Bhari Sharanesha; Das, Nagarajappa

    2014-01-01

    Adenomatoid odontogenic tumour is a relatively rare and distinct odontogenic tumour that is exclusively odontogenic epithelium in origin. It comprises 3% of all odontogenic tumours. This report describes the surgical therapy, clinical course and morphological characteristics of an adenomatoid odontogenic tumour that developed in the left maxilla of a 20-year-old patient. PMID:24810436

  4. Teacher Education 1992 and 2012: Reflecting on 20 Years

    ERIC Educational Resources Information Center

    McKeown, Rosalyn

    2012-01-01

    Over the past 20 years education for sustainable development (ESD) has become part of the discourse in teacher education and the teaching community has a better grasp of ESD's action-oriented and participatory pedagogies. The International Network of Teacher Education Institutions (TEIs) associated with the UNESCO Chair on Reorienting Teacher…

  5. Are History Textbooks More "Considerate" after 20 Years?

    ERIC Educational Resources Information Center

    Berkeley, Sheri; King-Sears, Margaret E.; Hott, Brittany L.; Bradley-Black, Katherine

    2014-01-01

    Features of eighth-grade history textbooks were examined through replication of a 20-year-old study that investigated "considerateness" of textbooks. Considerate texts provide clear, coherent information and include features that promote students' comprehension, such as explicit use of organizational structures, a range of question…

  6. The optimal manufacturing batch size with rework under time-varying demand process for a finite time horizon

    NASA Astrophysics Data System (ADS)

    Musa, Sarah; Supadi, Siti Suzlin; Omar, Mohd

    2014-07-01

    Rework is one of the solutions to some of the main issues in reverse logistic and green supply chain as it reduces production cost and environmental problem. Many researchers focus on developing rework model, but to the knowledge of the author, none of them has developed a model for time-varying demand rate. In this paper, we extend previous works and develop multiple batch production system for time-varying demand rate with rework. In this model, the rework is done within the same production cycle.

  7. New Horizons in Thermodynamics

    NASA Astrophysics Data System (ADS)

    Hayward, Geoffrey Gordon

    1991-02-01

    This thesis collects five papers which treat the theory of horizon thermodynamics and its applications to cosmology. In the first paper I consider general, spherically symmetric spacetimes with cosmological and black hole horizons. I find that a state of thermal equilibrium may exist in classical manifolds with two horizons so long as a matter distribution is present. I calculate the Euclidean action for non-classical manifolds with and without boundary and relate it to the grand canonical weighting factor. I find that the mean thermal energy of the cosmological horizon is negative. In the second paper I derive the first law of thermodynamics for bounded, static, spherically symmetric spacetimes which include a matter distribution and either a black hole or cosmological horizon. I calculate heat capacities associated with matter/horizon systems and find that they may be positive or negative depending on the matter configuration. I discuss the case in which the cosmological constant is allowed to vary and conclude that the Hawking/Coleman mechanisms for explaining the low value of the cosmological constant are not well formulated. In the third paper, co-authored by Jorma Louko, we analyze variational principles for non-smooth metrics. These principles give insight to the problem of constructing minisuperspace path integrals in horizon statistical mechanics and quantum cosmology. We demonstrate that smoothness conditions can be derived from the variational principle as equations of motion. We suggest a new prescription for minisuperspace path integrals on the manifold | D times S^2. In the fourth paper, I examine the contribution of the horizon energy density to black hole temperature. I show the existence of positive heat capacity solutions in the small mass regime. In the fifth paper, co-authored by Diego Pavon we investigate the role of primordial black holes in the very early universe under SU(3) times SU(2) times U (1), SU(5), and their supersymmetric

  8. The Chilean health system: 20 years of reforms.

    PubMed

    Manuel, Annick

    2002-01-01

    The Chilean health care system has been intensively reformed in the past 20 years. Reforms under the Pinochet government (1973-1990) aimed mainly at the decentralization of the system and the development of a private sector. Decentralization involved both a deconcentration process and the devolution of primary health care to municipalities. The democratic governments after 1990 chose to preserve the core organization but introduced reforms intended to correct the system's failures and to increase both efficiency and equity. The present article briefly explains the current organization of the Chilean health care system. It also reviews the different reforms introduced in the past 20 years, from the Pinochet regime to the democratic governments. Finally, a brief discussion describes the strengths and weaknesses of the system, as well as the challenges it currently faces.

  9. A Time-Series of Surface Oil Distribution Detected by Satellite SAR During the Deepwater Horizon Blowout

    NASA Astrophysics Data System (ADS)

    MacDonald, I. R.; Garcia-Pineda, O. G.; Solow, A.; Daneshgar, S.; Beet, A.

    2013-12-01

    Oil discharged as a result of the Deepwater Horizon disaster was detected on the surface of the Gulf of Mexico by synthetic aperture radar satellites from 25 April 2010 until 4 August 2010. SAR images were not restricted by daylight or cloud-cover. Distribution of this material is a tracer for potential environmental impacts and an indicator of impact mitigation due to response efforts and physical forcing factors. We used a texture classifying neural network algorithm for semi-supervised processing of 176 SAR images from the ENVISAT, RADARSAT I, and COSMO-SKYMED satellites. This yielded an estimate the proportion of oil-covered water within the region sampled by each image with a nominal resolution of 10,000 sq m (100m pixels), which was compiled as a 5-km equal area grid covering the northern Gulf of Mexico. Few images covered the entire impact area, so analysis was required to compile a regular time-series of the oil cover. A Gaussian kernel using a bandwidth of 2 d was used to estimate oil cover percent in each grid at noon and midnight throughout the interval. Variance and confidence intervals were calculated for each grid and for the global 12-h totals. Results animated across the impact region show the spread of oil under the influence of physical factors. Oil cover reached an early peak of 17032.26 sq km (sd 460.077) on 18 May, decreasing to 27% of this total on 4 June, following by sharp increase to an overall maximum of 18424.56 sq km (sd 424.726) on 19 June. There was a significant negative correlation between average wind stress and the total area of oil cover throughout the time-series. Correlation between response efforts including aerial and subsurface application of dispersants and burning of gathered oil was negative, positive, or indeterminate at different time segments during the event. Daily totals for oil-covered surface waters of the Gulf of Mexico during 25 April - 9 August 2010 with upper and lower 0.95 confidence limits on estimate. (No oil

  10. Evolution of US DOE Performance Assessments Over 20 Years - 13597

    SciTech Connect

    Suttora, Linda C.; Seitz, Roger R.

    2013-07-01

    Performance assessments (PAs) have been used for many years for the analysis of post-closure hazards associated with a radioactive waste disposal facility and to provide a reasonable expectation of the ability of the site and facility design to meet objectives for the protection of members of the public and the environment. The use of PA to support decision-making for LLW disposal facilities has been mandated in United States Department of Energy (US DOE) directives governing radioactive waste management since 1988 (currently DOE Order 435.1, Radioactive Waste Management). Prior to that time, PAs were also used in a less formal role. Over the past 20+ years, the US DOE approach to conduct, review and apply PAs has evolved into an efficient, rigorous and mature process that includes specific requirements for continuous improvement and independent reviews. The PA process has evolved through refinement of a graded and iterative approach designed to help focus efforts on those aspects of the problem expected to have the greatest influence on the decision being made. Many of the evolutionary changes to the PA process are linked to the refinement of the PA maintenance concept that has proven to be an important element of US DOE PA requirements in the context of supporting decision-making for safe disposal of LLW. The PA maintenance concept is central to the evolution of the graded and iterative philosophy and has helped to drive the evolution of PAs from a deterministic compliance calculation into a systematic approach that helps to focus on critical aspects of the disposal system in a manner designed to provide a more informed basis for decision-making throughout the life of a disposal facility (e.g., monitoring, research and testing, waste acceptance criteria, design improvements, data collection, model refinements). A significant evolution in PA modeling has been associated with improved use of uncertainty and sensitivity analysis techniques to support efficient

  11. Evolution Of USDOE Performance Assessments Over 20 Years

    SciTech Connect

    Seitz, Roger R.; Suttora, Linda C.

    2013-02-26

    Performance assessments (PAs) have been used for many years for the analysis of post-closure hazards associated with a radioactive waste disposal facility and to provide a reasonable expectation of the ability of the site and facility design to meet objectives for the protection of members of the public and the environment. The use of PA to support decision-making for LLW disposal facilities has been mandated in United States Department of Energy (USDOE) directives governing radioactive waste management since 1988 (currently DOE Order 435.1, Radioactive Waste Management). Prior to that time, PAs were also used in a less formal role. Over the past 20+ years, the USDOE approach to conduct, review and apply PAs has evolved into an efficient, rigorous and mature process that includes specific requirements for continuous improvement and independent reviews. The PA process has evolved through refinement of a graded and iterative approach designed to help focus efforts on those aspects of the problem expected to have the greatest influence on the decision being made. Many of the evolutionary changes to the PA process are linked to the refinement of the PA maintenance concept that has proven to be an important element of USDOE PA requirements in the context of supporting decision-making for safe disposal of LLW. The PA maintenance concept represents the evolution of the graded and iterative philosophy and has helped to drive the evolution of PAs from a deterministic compliance calculation into a systematic approach that helps to focus on critical aspects of the disposal system in a manner designed to provide a more informed basis for decision-making throughout the life of a disposal facility (e.g., monitoring, research and testing, waste acceptance criteria, design improvements, data collection, model refinements). A significant evolution in PA modeling has been associated with improved use of uncertainty and sensitivity analysis techniques to support efficient

  12. [False aneurysm on dacron prosthesis, 20 years after aortofemoral bypass].

    PubMed

    Illuminati, G; Bertagni, A; Nasti, A G; Montesano, G

    2001-10-01

    A 85-year-old male developed a false, non septic, non anastomotic aneurysm, 20 years after right aorto-femoral Dacron grafting for claudication. On account of the proximity to the femoral anastomosis, and the association with a profunda femoris stenosis, a conventional surgical repair was preferred to an endovascular treatment. The patient underwent a successful aneurysm resection followed by PTFE interposition between the primary graft and the profunda femoris artery, with uneventful recovery.

  13. LaRC 20-Year Center Revitalization Plan

    NASA Technical Reports Server (NTRS)

    Mangum, Cathy H.; Harris, Charles E.; Allen, Cheryl L.; Craft, Stephen J.; Hope, Drew J.; Kegelman, Jerome T.; Mastaler, Michael D; Weiser, Erik S.

    2012-01-01

    LaRC has developed a 20-Year Center Revitalization Plan. The objective of this plan is to assure that the center infrastructure is sustainable for the long-term and that the center will have the essential facilities and laboratories to execute the future NASA mission. The plan was developed by a centerwide team, VITAL, and was approved by the Center Leadership Council (CLC) in March 2012. The revitalization plan will be implemented through the Center Master Planning process.

  14. [False aneurysm on dacron prosthesis, 20 years after aortofemoral bypass].

    PubMed

    Illuminati, G; Bertagni, A; Nasti, A G; Montesano, G

    2001-10-01

    A 85-year-old male developed a false, non septic, non anastomotic aneurysm, 20 years after right aorto-femoral Dacron grafting for claudication. On account of the proximity to the femoral anastomosis, and the association with a profunda femoris stenosis, a conventional surgical repair was preferred to an endovascular treatment. The patient underwent a successful aneurysm resection followed by PTFE interposition between the primary graft and the profunda femoris artery, with uneventful recovery. PMID:11692765

  15. Posttraumatic Intrusion, Avoidance, and Social Functioning: A 20-Year Longitudinal Study

    ERIC Educational Resources Information Center

    Solomon, Zahava; Mikulincer, Mario

    2007-01-01

    The study assesses posttraumatic intrusion, avoidance, and social functioning among 214 Israeli combat veterans from the first Lebanon War with and without combat stress reaction (CSR) 1, 2, 3, and 20 years after the war. CSR veterans reported higher intrusion and avoidance than did non-CSR veterans. With time, there was a decline in these…

  16. Adult Children and Their Fathers: Relationship Changes 20 Years after Parental Divorce.

    ERIC Educational Resources Information Center

    Ahrons, Constance R.; Tanner, Jennifer L.

    2003-01-01

    Examines adult children's reports of relationship changes with their fathers were 20 years after their parents' divorce. Findings indicated that most adult children felt that their relationships with their fathers had either improved or remained stable over time. Custody did not directly affect reported changes in the quality of their relationship…

  17. CANADARM: 20 Years of Mission Success Through Adaptation

    NASA Technical Reports Server (NTRS)

    Hiltz, Michael; Rice, Craig; Boyle, Keith; Allison, Ronald

    2001-01-01

    As part of the National Aeronautics and Space Administration's Space Shuttle Transportation System, the Shuttle Remote Manipulator System has played a vital role in the success of 60 space missions. This paper concludes that the robustness and success of the Canadarm over its 20 year life can be attributed to the adaptations that have been made to it to meet the increased demands that have been placed on the system. Enhancements that have been made to the arm to improve its operational capabilities, reduce risk and extend its life are examined in this paper. Potential future enhancements based on operational trends are also discussed.

  18. Mechanics of rotating isolated horizons

    SciTech Connect

    Ashtekar, Abhay; Beetle, Christopher; Lewandowski, Jerzy

    2001-08-15

    Black hole mechanics was recently extended by replacing the more commonly used event horizons in stationary space-times with isolated horizons in more general space-times (which may admit radiation arbitrarily close to black holes). However, so far the detailed analysis has been restricted to nonrotating black holes (although it incorporated arbitrary distortion, as well as electromagnetic, Yang-Mills, and dilatonic charges). We now fill this gap by first introducing the notion of isolated horizon angular momentum and then extending the first law to the rotating case.

  19. Earth observation photography: Looking back 20 years after Skylab

    NASA Technical Reports Server (NTRS)

    Nicholson, James H.

    1992-01-01

    A committee of trained classroom teachers, backed by a volunteer team of technical experts and academic advisors has developed a program for earth science based on photographs obtained from low earth orbit. In selecting targeting objectives, immediate note was made of the fact nearly one generation (20 years) has passed since the United States' ambitious SKYLAB program was conducted. A critical part of those missions was the acquisition of earth photography using a six camera, multi-spectral camera system. This objective was systematically furthered through the term of three separate crew visits to the Space Station. Not merely an exercise in randomly photographing the Earth below, the purpose of the Earth Resource Experiment Package (EREP) was to determine what kind, and how much, photographic data could be acquired of the broad variety of Earth features witnessed on the mission's ground track. The collection of 35,000 photos produced by EREP represents the most complete coverage of Earth. However, it remains under used. GAS 324 intends to revisit, and to add a tier of relevancy to this inventory. The photography of GAS 324 should allow a direct examination and comparison of the changes in the globe in the last 20 years. format in both coverage and quality. The photogra phy acquired by CAN DO should allow a direct examination and comparison of the changes that have occured to the Globe in the last twenty years.

  20. Endoscopic-assisted epiphysiodesis: technique and 20-year experience.

    PubMed

    Ledesma, Justin B; Wang, Tianyi; Desmond, Elizabeth; Imrie, Meghan; Gamble, James G; Rinsky, Lawrence A

    2016-01-01

    The aim of the study was to describe the endoscopic-assisted epiphysiodesis technique and review our 20-year experience with it. A retrospective review of 44 patients who underwent proximal tibia and/or distal femur endoscopic-assisted epiphysiodesis was carried out. Only patients who had preoperative and postoperative scanograms with clinical follow-up of at least 6 months were included. The mean length of follow-up was 36.8 months. All patients had radiographic evidence of physeal fusion within 6-12 months from the index procedure. No patient required revision surgery. Endoscopic-assisted epiphysiodesis is safe, effective, and achieves predictable physeal fusion. Advantages over current techniques include reduced radiation exposure and lack of requirement for hardware placement.

  1. Leptin, 20 years of searching for glucose homeostasis.

    PubMed

    Fernández-Formoso, Gabriela; Pérez-Sieira, Sonia; González-Touceda, David; Dieguez, Carlos; Tovar, Sulay

    2015-11-01

    Leptin was discovered in 1994 (20 years ago). In addition to having well-characterized effects on the regulation of energy homeostasis, leptin clearly also plays a major role in metabolic homeostasis. In fact, leptin plays an important role in the regulation of glucose homeostasis independent of food intake and body weight. The mechanism underlying the modulation of glucose metabolism by leptin is not completely understood, although evidence indicates that the effect occurs at both the central and peripheral levels. In this review, we will focus on the role of leptin in glucose homeostasis at the central level and its role in insulin secretion and in counteracting hormones, such as glucagon, growth hormone, cortisol and catecholamines.

  2. Residential Transitions among Adults with Intellectual Disability across 20 Years

    PubMed Central

    Woodman, Ashley C.; Mailick, Marsha R.; Anderson, Kristy A.; Esbensen, Anna J.

    2014-01-01

    The present study addresses critical gaps in the literature by examining residential transitions among 303 adults with intellectual disability over 10 years (Part 1) and 75 adults with Down syndrome over 20 years (Part 2). All adults lived at home at the start of the study, but many moved to a variety of settings. Several characteristics of the adults with intellectual disability differed across settings, most notably adaptive behavior and the number of residential transitions, while characteristics such as age, type of disability, and behavior problems were less predictive of residential placements. The number of moves over the course of the study varied widely, with critical links to earlier family dynamics, social relationships, and health and adaptive behavior. PMID:25354121

  3. Carcinoma of the hand: a 20-year experience

    SciTech Connect

    Bean, D.J.; Rees, R.S.; O'Leary, J.P.; Lynch, J.B.

    1984-08-01

    We reviewed our 20-year experience with cutaneous carcinoma of the hand and identified 70 cases (basal cell 23%, squamous cell 77%). The documented risk factors included solar radiation, trauma, and irradiation. Lesions were treated surgically with amputation, excision, skin graft, or flap closure, and nonsurgically with cryosurgery, curettage, 5-fluorouracil, or irradiation. The recurrence was lower with surgical treatment (3%) than with nonsurgical (33%). Regional lymphadenectomy was required in four patients for metastatic squamous cell carcinoma. Recurrence was greater (9%) and metastasis more common (38%) in patients with Marjolin's type of secondary squamous cell carcinoma than with solar-induced lesions. Cause is an important factor in outcome and should be considered in initial treatment and long-term management.

  4. Carcinoma of the hand: a 20-year experience

    SciTech Connect

    Bean, D.J.; Rees, R.S.; O'Leary, J.P.; Lynch, J.B.

    1984-08-01

    The authors reviewed their 20-year experience with cutaneous carcinoma of the hand and identified 70 cases (basal cell 23%, squamous cell 77%). The documented risk factors included solar radiation, trauma, and irradiation. Lesions were treated surgically with amputation, excision, skin graft, or flap closure, and nonsurgically with cryosurgery, curettage, 5-fluorouracil, or irradiation. The recurrence was lower with surgical treatment (3%) than with nonsurgical (33%). Regional lymphadenectomy was required in four patients for metastatic squamous cell carcinoma. Recurrence was greater (9%) and metastasis more common (38%) in patients with Marjolin's type of secondary squamous cell carcinoma than with solar-induced lesions. Cause is an important factor in outcome and should be considered in initial treatment and long-term management.

  5. EDITORIAL: Nonlinearity is 20 years old in 2008!

    NASA Astrophysics Data System (ADS)

    Keating, J. P.; Neishtadt, A. I.

    2008-01-01

    During the past 20 years the journal has published many of the subject-defining papers in the field of nonlinear mathematics and its applications. These have ranged from fundamental developments in the theory of dynamical systems and differential equations to applications in atmospheric dynamics, astrophysics, biology, chemistry, fluid dynamics, networks, quantum chaos and statistical physics, to give just a few examples. The field has changed considerably since the journal was founded. In particular, some applications, once considered little more than wishful thinking, have now matured and spun off to form their own journals, or to find homes in journals that might once have thought them too esoteric or too mathematical. In their place have come exciting new applications for which the fundamental mathematical ideas are still to be developed. Nonlinearity has played a leading role in these developments and we look back with pride. But birthdays are also occasions when one should look forward, and with this in mind, as part of our birthday celebrations, we have commissioned for publication in 2008 a series of short articles, entitled Open Problems, from leading researchers in the field. Each article represents the author's personal selection of some interesting and/or important open problems or conjectures. They are not intended to be systematic lists, or encyclopaedic in coverage, but are, rather, individual perspectives on some of the problems and challenges, large and small, that would be worth solving. Our hope is that these articles will contribute to setting the agenda for the next 20 years, and beyond. We took great pleasure in inviting these articles and hope that readers of Nonlinearity will find them interesting, stimulating, and perhaps, in some cases, even provocative. We certainly look forward to seeing, and maybe even publishing, solutions to the problems they describe!

  6. African Savanna-Forest Boundary Dynamics: A 20-Year Study.

    PubMed

    Cuni-Sanchez, Aida; White, Lee J T; Calders, Kim; Jeffery, Kathryn J; Abernethy, Katharine; Burt, Andrew; Disney, Mathias; Gilpin, Martin; Gomez-Dans, Jose L; Lewis, Simon L

    2016-01-01

    Recent studies show widespread encroachment of forest into savannas with important consequences for the global carbon cycle and land-atmosphere interactions. However, little research has focused on in situ measurements of the successional sequence of savanna to forest in Africa. Using long-term inventory plots we quantify changes in vegetation structure, above-ground biomass (AGB) and biodiversity of trees ≥10 cm diameter over 20 years for five vegetation types: savanna; colonising forest (F1), monodominant Okoume forest (F2); young Marantaceae forest (F3); and mixed Marantaceae forest (F4) in Lopé National Park, central Gabon, plus novel 3D terrestrial laser scanning (TLS) measurements to assess forest structure differences. Over 20 years no plot changed to a new stage in the putative succession, but F1 forests strongly moved towards the structure, AGB and diversity of F2 forests. Overall, savanna plots showed no detectable change in structure, AGB or diversity using this method, with zero trees ≥10 cm diameter in 1993 and 2013. F1 and F2 forests increased in AGB, mainly as a result of adding recruited stems (F1) and increased Basal Area (F2), whereas F3 and F4 forests did not change substantially in structure, AGB or diversity. Critically, the stability of the F3 stage implies that this stage may be maintained for long periods. Soil carbon was low, and did not show a successional gradient as for AGB and diversity. TLS vertical plant profiles showed distinctive differences amongst the vegetation types, indicating that this technique can improve ecological understanding. We highlight two points: (i) as forest colonises, changes in biodiversity are much slower than changes in forest structure or AGB; and (ii) all forest types store substantial quantities of carbon. Multi-decadal monitoring is likely to be required to assess the speed of transition between vegetation types. PMID:27336632

  7. African Savanna-Forest Boundary Dynamics: A 20-Year Study

    PubMed Central

    Cuni-Sanchez, Aida; White, Lee J. T.; Calders, Kim; Jeffery, Kathryn J.; Abernethy, Katharine; Burt, Andrew; Disney, Mathias; Gilpin, Martin; Gomez-Dans, Jose L.; Lewis, Simon L.

    2016-01-01

    Recent studies show widespread encroachment of forest into savannas with important consequences for the global carbon cycle and land-atmosphere interactions. However, little research has focused on in situ measurements of the successional sequence of savanna to forest in Africa. Using long-term inventory plots we quantify changes in vegetation structure, above-ground biomass (AGB) and biodiversity of trees ≥10 cm diameter over 20 years for five vegetation types: savanna; colonising forest (F1), monodominant Okoume forest (F2); young Marantaceae forest (F3); and mixed Marantaceae forest (F4) in Lopé National Park, central Gabon, plus novel 3D terrestrial laser scanning (TLS) measurements to assess forest structure differences. Over 20 years no plot changed to a new stage in the putative succession, but F1 forests strongly moved towards the structure, AGB and diversity of F2 forests. Overall, savanna plots showed no detectable change in structure, AGB or diversity using this method, with zero trees ≥10 cm diameter in 1993 and 2013. F1 and F2 forests increased in AGB, mainly as a result of adding recruited stems (F1) and increased Basal Area (F2), whereas F3 and F4 forests did not change substantially in structure, AGB or diversity. Critically, the stability of the F3 stage implies that this stage may be maintained for long periods. Soil carbon was low, and did not show a successional gradient as for AGB and diversity. TLS vertical plant profiles showed distinctive differences amongst the vegetation types, indicating that this technique can improve ecological understanding. We highlight two points: (i) as forest colonises, changes in biodiversity are much slower than changes in forest structure or AGB; and (ii) all forest types store substantial quantities of carbon. Multi-decadal monitoring is likely to be required to assess the speed of transition between vegetation types. PMID:27336632

  8. African Savanna-Forest Boundary Dynamics: A 20-Year Study.

    PubMed

    Cuni-Sanchez, Aida; White, Lee J T; Calders, Kim; Jeffery, Kathryn J; Abernethy, Katharine; Burt, Andrew; Disney, Mathias; Gilpin, Martin; Gomez-Dans, Jose L; Lewis, Simon L

    2016-01-01

    Recent studies show widespread encroachment of forest into savannas with important consequences for the global carbon cycle and land-atmosphere interactions. However, little research has focused on in situ measurements of the successional sequence of savanna to forest in Africa. Using long-term inventory plots we quantify changes in vegetation structure, above-ground biomass (AGB) and biodiversity of trees ≥10 cm diameter over 20 years for five vegetation types: savanna; colonising forest (F1), monodominant Okoume forest (F2); young Marantaceae forest (F3); and mixed Marantaceae forest (F4) in Lopé National Park, central Gabon, plus novel 3D terrestrial laser scanning (TLS) measurements to assess forest structure differences. Over 20 years no plot changed to a new stage in the putative succession, but F1 forests strongly moved towards the structure, AGB and diversity of F2 forests. Overall, savanna plots showed no detectable change in structure, AGB or diversity using this method, with zero trees ≥10 cm diameter in 1993 and 2013. F1 and F2 forests increased in AGB, mainly as a result of adding recruited stems (F1) and increased Basal Area (F2), whereas F3 and F4 forests did not change substantially in structure, AGB or diversity. Critically, the stability of the F3 stage implies that this stage may be maintained for long periods. Soil carbon was low, and did not show a successional gradient as for AGB and diversity. TLS vertical plant profiles showed distinctive differences amongst the vegetation types, indicating that this technique can improve ecological understanding. We highlight two points: (i) as forest colonises, changes in biodiversity are much slower than changes in forest structure or AGB; and (ii) all forest types store substantial quantities of carbon. Multi-decadal monitoring is likely to be required to assess the speed of transition between vegetation types.

  9. Refraction near the horizon

    NASA Technical Reports Server (NTRS)

    Schaefer, Bradley E.; Liller, William

    1990-01-01

    Variations in astronomical refraction near the horizon are examined. Sunset timings, a sextant mounted on a tripod, and a temperature profile are utilized to derive the variations in refraction data, collected from 7 locations. It is determined that the refraction ranges from 0.234 to 1.678 deg with an rms deviation of 0.16, and it is observed that the variation is larger than previously supposed. Some applications for the variation of refraction value are discussed.

  10. New Horizons at Jupiter

    NASA Astrophysics Data System (ADS)

    Stern, S. Alan

    2007-12-01

    New Horizons is NASA's reconnaissance mission to explore the Pluto system and small Kuiper Belt Objects (KBOs). I will describe the mission's history, current status, and instrument suite. I will then describe the Jupiter gravity assist flyby New Horizons conducted in early-mid 2007. This flyby involved over 700 observations in the Jupiter system, and represents the only spacecraft encounter with Jupiter planned to occur between the demise of Galileo in 2003 and the arrival of Juno in 2016. I will focus on results obtained, including the first-ever exploration of a giant planet magnetotail, new compositional observations of icy Galilean satellites, exploration of Jupiter's tenuous ring system, the first high-resolution spacecraft imagery of Jupiter's newly-generated little red spot, and the first-ever time-lapse imagery of an Ionian volcano eruption.

  11. HORIZON SENSING (PROPOSAL No.51)

    SciTech Connect

    Larry G. Stolarczyk, Sc.D.

    2002-04-30

    Real-time horizon sensing on continuous mining machines is becoming an industry tool. Installation and testing of production-grade HS systems has been ongoing this quarter at Monterey Coal Company (EXXON), FMC Trona, Twentymile Coal Company (RAG America), and SASOL Coal. Detailed monitoring of system function, user experience, and mining benefits is ongoing. All horizon sensor components have finished MSHA (U.S.) and IEC (International) certification.

  12. A 20-year simulated climatology of global dust aerosol deposition.

    PubMed

    Zheng, Yu; Zhao, Tianliang; Che, Huizheng; Liu, Yu; Han, Yongxiang; Liu, Chong; Xiong, Jie; Liu, Jianhui; Zhou, Yike

    2016-07-01

    Based on a 20-year (1991-2010) simulation of dust aerosol deposition with the global climate model CAM5.1 (Community Atmosphere Model, version 5.1), the spatial and temporal variations of dust aerosol deposition were analyzed using climate statistical methods. The results indicated that the annual amount of global dust aerosol deposition was approximately 1161±31Mt, with a decreasing trend, and its interannual variation range of 2.70% over 1991-2010. The 20-year average ratio of global dust dry to wet depositions was 1.12, with interannual variation of 2.24%, showing the quantity of dry deposition of dust aerosol was greater than dust wet deposition. High dry deposition was centered over continental deserts and surrounding regions, while wet deposition was a dominant deposition process over the North Atlantic, North Pacific and northern Indian Ocean. Furthermore, both dry and wet deposition presented a zonal distribution. To examine the regional changes of dust aerosol deposition on land and sea areas, we chose the North Atlantic, Eurasia, northern Indian Ocean, North Pacific and Australia to analyze the interannual and seasonal variations of dust deposition and dry-to-wet deposition ratio. The deposition amounts of each region showed interannual fluctuations with the largest variation range at around 26.96% in the northern Indian Ocean area, followed by the North Pacific (16.47%), Australia (9.76%), North Atlantic (9.43%) and Eurasia (6.03%). The northern Indian Ocean also had the greatest amplitude of interannual variation in dry-to-wet deposition ratio, at 22.41%, followed by the North Atlantic (9.69%), Australia (6.82%), North Pacific (6.31%) and Eurasia (4.36%). Dust aerosol presented a seasonal cycle, with typically strong deposition in spring and summer and weak deposition in autumn and winter. The dust deposition over the northern Indian Ocean exhibited the greatest seasonal change range at about 118.00%, while the North Atlantic showed the lowest seasonal

  13. Who Needs a Revision? 20 Years of Cambridge Shunt Lab.

    PubMed

    Czosnyka, Zofia; Czosnyka, Marek; Pickard, John D; Chari, Aswin

    2016-01-01

    Shunt testing independent of manufacturers provides knowledge that can significantly improve the management of patients with hydrocephalus. The Cambridge Shunt Evaluation Laboratory was created 20 years ago. Thanks to financial support from the Department of Health (1993-1998), all shunts in use in the UK were systematically evaluated, with "blue reports" being published. Later new devices were tested as they appeared in public domain.Twenty-six models have been evaluated. The majority of the valves had a non-physiologically low hydrodynamic resistance that may result in over-drainage, both related to posture and during nocturnal cerebral vasogenic waves. A long distal catheter increases the resistance of these valves by 100-200 %. Drainage through valves without a siphon-preventing mechanism is very sensitive to body posture. Shunts with siphon-preventing accessories offer a reasonable resistance to negative outlet pressure. Bench parameters were used to test shunt performance in vivo using infusion tests. A criterion for correctly performing a shunt procedure was established. Pressure measured in the shunt prechamber during the plateau phase of infusion should not remain more than 5 mmHg above the le shunt's operating pressure plus hydrodynamic resistance of the valve multiplied by the infusion rate. "Critical levels" for every shunt and every performance level have been used in the shunt testing wizard of ICM+ software.

  14. Choroidal osteoma: evidence of progression and decalcification over 20 years.

    PubMed

    Chen, Jennifer; Lee, Lawrence; Gass, J Donald M

    2006-03-01

    Choroidal osteoma is a rare, benign, ossifying tumour of the choroid of unknown aetiology. In contrast to other types of intraocular ossification, choroidal osteoma is found typically in young healthy females in the second or third decades of life with no history of systemic or ocular disease. Choroidal osteoma is a deep, pale yellow lesion with distinct geographic borders at the juxtapapillary or macular region, with branching 'spider' vessels on the surface of the tumour. These features should help differentiate choroidal osteoma from other types of intraocular tumour and the diagnosis can be confirmed with ultrasonography and computerised tomography. Here we report an initially unilateral case of choroidal osteoma, which decalcified over 20 years but during the same period the fellow eye also developed a choroidal osteoma to become a bilateral case. Despite the benign nature of the tumour, vision may be compromised by gradual atrophy of the overlying retina, serous retinal detachment, accumulation of sub-retinal fluid and sub-retinal haemorrhage associated with choroidal neovascularisation. Frequent examinations are recommended for patients with choroidal osteoma, for early detection of a subretinal neovascular membrane and potential treatment with laser photocoagulation.

  15. 20 years of microplasma research: a status report

    NASA Astrophysics Data System (ADS)

    Schoenbach, Karl H.; Becker, Kurt

    2016-02-01

    The field of microplasmas gained recognition as a well-defined area of research and application within the larger field of plasma science and technology about 20 years ago. Since then, the activity in microplasma research and applications has continuously increased. A survey of peer reviewed papers on microplasmas published annually shows a steady increase from fewer than 20 papers in 1995 to about 75 in 2005 and more than 150 in 2014. This count excludes papers that deal exclusively with technological applications where the microplasma is used solely as a tool. This topical review aims to provide a snap shot of the current state of microplasma research and applications. Given the rapid proliferation of microplasma applications, the topical review will focus primarily on the status of microplasma science and our understanding of the physics principles that enable microplasma operation. Where appropriate, we will also address microplasma applications, however, we will limit the discussion of microplasma applications to examples where the application is closely tied to the plasma science. No attempt is made to provide a comprehensive and in-depth review of the diverse range of all microplasma applications, except for the inclusion of a few key references to recent reviews of microplasma applications.

  16. The Shenandoah Watershed Study: 20 years of Catchment Hydrogeochemistry

    NASA Astrophysics Data System (ADS)

    Galloway, J.

    2002-05-01

    changes and understanding of landscape controls (especially geologic setting) on watershed processes. This poster will present an overview of the critical findings of this 20-year research program.

  17. South american geochronology: radiometric time scale for middle to late tertiary mammal-bearing horizons in patagonia.

    PubMed

    Marshall, L G; Pascual, R; Curtis, G H; Drake, R E

    1977-03-25

    Radiometric (potassium-argon) age determinations for basalts and tuffs associated with middle to late Tertiary mammal-bearing horizons in Patagonia, southern Argentina, permit refinement of boundaries and hiatuses between beds of Deseadan (early Oligocene) through Friasian (middle to late Miocene) age. At two localities beds of Deseadan age are overlain by basalts, which gave dates of 33.6 and 35.4 million years ago; 34.0 million years ago is tentatively accepted as a terminal date for known Deseadan. At several localities beds of Colhuehuapian age are underlain by basalts, which gave dates ranging from 28.8 to 24.3 million years ago; 25.0 million years is tentatively taken as a basal age for known Colhuehuapian. The paleontological hiatus between known Deseadan and known Colhuehuapian is thus in the order of 9.0 million years. Two tuffs from the Santa Cruz Formation (Santacrucian) gave ages of 21.7 and 18.5 million years. Plagioclase and biotite concentrates of an ignimbrite from the Collón Curá Formation (Friasian) gave ages ranging from 15.4 to 14.0 million years. PMID:17738414

  18. South american geochronology: radiometric time scale for middle to late tertiary mammal-bearing horizons in patagonia.

    PubMed

    Marshall, L G; Pascual, R; Curtis, G H; Drake, R E

    1977-03-25

    Radiometric (potassium-argon) age determinations for basalts and tuffs associated with middle to late Tertiary mammal-bearing horizons in Patagonia, southern Argentina, permit refinement of boundaries and hiatuses between beds of Deseadan (early Oligocene) through Friasian (middle to late Miocene) age. At two localities beds of Deseadan age are overlain by basalts, which gave dates of 33.6 and 35.4 million years ago; 34.0 million years ago is tentatively accepted as a terminal date for known Deseadan. At several localities beds of Colhuehuapian age are underlain by basalts, which gave dates ranging from 28.8 to 24.3 million years ago; 25.0 million years is tentatively taken as a basal age for known Colhuehuapian. The paleontological hiatus between known Deseadan and known Colhuehuapian is thus in the order of 9.0 million years. Two tuffs from the Santa Cruz Formation (Santacrucian) gave ages of 21.7 and 18.5 million years. Plagioclase and biotite concentrates of an ignimbrite from the Collón Curá Formation (Friasian) gave ages ranging from 15.4 to 14.0 million years.

  19. Bringing Together Simulated ~20 Year Variability in Coupled Climate Models

    NASA Astrophysics Data System (ADS)

    Menary, M.; Hodson, D.; Robson, J.; Sutton, R.; Wood, R. A.

    2014-12-01

    Many climate models simulate significant spectral power in large scale, North Atlantic subpolar gyre indices at timescales of around 20 years. Despite similar periodicities, the underlying mechanisms reported in individual models can vary greatly. For example, the timescale can be set by any combination of geostrophic self advection, Rossby wave propagation, or advection by the mean circulation. The role of the overturning circulation can either be active or passive, and the ultimate driver of density changes in the deep water formation regions is split roughly evenly in the literature between salinity and temperature - with implications for any feedback mechanisms. These simulations typically span many centuries with constant external forcings to capture internal climate variability. The extent to which either this periodicity carries over to the real world under increasingly strong external forcing, or which, if any, of the modelled feedbacks are applicable, is unclear. We present new results from a state-of-the-art high resolution coupled climate model (HadGEM3) in which the mechanism of internal decadal variability in the North Atlantic is diagnosed and discuss the causes of differences from previous work. Due to the non-linear equation of state, biases in the simulated mean state can explain some of the inter-model differences via the relative importance of temperature or salinity in density changes. These biases can then propagate throughout the mechanistic chain resulting in fundamentally different simulated mechanisms. For example, whether temperature or salinity control densities in the Labrador Sea influences whether a strengthening overturning circulation acts as a negative or positive feedback. Although analysis of the model proceeds via lagged regressions, this is generally not possible with observational data. We use a combination of palaeo reconstructions and targeted process-based analysis to investigate whether there is any signal of bidecadal

  20. Pluto's Atmosphere from the 2015 June 29 Ground-based Stellar Occultation at the Time of the New Horizons Flyby

    NASA Astrophysics Data System (ADS)

    Sicardy, B.; Talbot, J.; Meza, E.; Camargo, J. I. B.; Desmars, J.; Gault, D.; Herald, D.; Kerr, S.; Pavlov, H.; Braga-Ribas, F.; Assafin, M.; Benedetti-Rossi, G.; Dias-Oliveira, A.; Gomes-Júnior, A. R.; Vieira-Martins, R.; Bérard, D.; Kervella, P.; Lecacheux, J.; Lellouch, E.; Beisker, W.; Dunham, D.; Jelínek, M.; Duffard, R.; Ortiz, J. L.; Castro-Tirado, A. J.; Cunniffe, R.; Querel, R.; Yock, P. C.; Cole, A. A.; Giles, A. B.; Hill, K. M.; Beaulieu, J. P.; Harnisch, M.; Jansen, R.; Pennell, A.; Todd, S.; Allen, W. H.; Graham, P. B.; Loader, B.; McKay, G.; Milner, J.; Parker, S.; Barry, M. A.; Bradshaw, J.; Broughton, J.; Davis, L.; Devillepoix, H.; Drummond, J.; Field, L.; Forbes, M.; Giles, D.; Glassey, R.; Groom, R.; Hooper, D.; Horvat, R.; Hudson, G.; Idaczyk, R.; Jenke, D.; Lade, B.; Newman, J.; Nosworthy, P.; Purcell, P.; Skilton, P. F.; Streamer, M.; Unwin, M.; Watanabe, H.; White, G. L.; Watson, D.

    2016-03-01

    We present results from a multi-chord Pluto stellar occultation observed on 2015 June 29 from New Zealand and Australia. This occurred only two weeks before the NASA New Horizons flyby of the Pluto system and serves as a useful comparison between ground-based and space results. We find that Pluto's atmosphere is still expanding, with a significant pressure increase of 5 ± 2% since 2013 and a factor of almost three since 1988. This trend rules out, as of today, an atmospheric collapse associated with Pluto's recession from the Sun. A central flash, a rare occurrence, was observed from several sites in New Zealand. The flash shape and amplitude are compatible with a spherical and transparent atmospheric layer of roughly 3 km in thickness whose base lies at about 4 km above Pluto's surface, and where an average thermal gradient of about 5 K km-1 prevails. We discuss the possibility that small departures between the observed and modeled flash are caused by local topographic features (mountains) along Pluto's limb that block the stellar light. Finally, using two possible temperature profiles, and extrapolating our pressure profile from our deepest accessible level down to the surface, we obtain a possible range of 11.9-13.7 μbar for the surface pressure. Partly based on observations made with the ESO WFI camera at the 2.2 m Telescope (La Silla), under program ID 079.A-9202(A) within the agreement between the ON/MCTI and the Max Planck Society, with the ESO camera NACO at the Very Large Telescope (Paranal), under program ID 089.C-0314(C), and at the Pico dos Dias Observatory/LNA, Brazil.

  1. Vertical patterns of ecoenzyme activities in forest soils after 20 years of simulated nitrogen deposition

    NASA Astrophysics Data System (ADS)

    Forstner, Stefan J.; Kloss, Stefanie; Keiblinger, Katharina M.; Schleppi, Patrick; Hagedorn, Frank; Gundersen, Per; Wanek, Wolfgang; Gerzabek, Martin H.; Zechmeister-Boltenstern, Sophie

    2015-04-01

    The below-ground part of terrestrial carbon (C), nitrogen (N) and phosphorus (P) cycles are controlled by soil microorganisms. In order to meet their energy and nutrient requirements, soil microbes produce enzymes which catalyze the release of smaller molecules from decomposing organic matter. Recent work has shown that the potential activities of commonly measured enzymes for C-, N-, and P-acquisition can be related to microbial demand of these elements and link stoichiometry of soil microbes and their resources. Regulation of enzyme production might therefore be an important mechanism for microbes to adapt to different resource regimes. To investigate links between ecoenzyme activities, soil depth and N availability we make use of two long-term experiments where N has been added to two temperate forest stands for over 20 years. At both sites Norway spruce is the dominating tree whereas other site characteristics like soil type, climate, parent material and morphology differ. Increased N deposition was simulated by regularly applying NH4NO3 in the range of 35 kg N ha-1 y-1 (Klosterhede, Denmark; since 1992) and 25 kg N ha-1 y-1 (Alptal, Switzerland; since 1995), respectively. We hypothesize that ecoenzyme activities will decline exponentially with depth reflecting well-established similar trends in organic matter and microbial biomass. However, when normalized to microbial biomass we further hypothesize that activities will not change or even increase down the soil profile. Concerning microbial nutrient limitation, we expect to see a shift from N- to C-limitation with depth which should be reflected in increasing ratios of C- to N-acquiring enzymes. Preliminary results suggest that activity of hydrolytic enzymes generally decreases with depth, although this drop in activity is not so pronounced when normalized to microbial biomass. Oxidative enzymes, on the other hand, do not follow this pattern, often showing increased activities with depth. We further see site

  2. [Verrucous carcinoma of the larynx. An analysis of 20 years of experience].

    PubMed

    López Amado, M; Lozano Ramírez, A; Labella Caballero, T

    1997-01-01

    Retrospective study about 10 verrucous carcinomas of the larynx surgically treated in a 20-year-term. This variety accounted por the 1.9 percent of the cancers seen in that period of time. Tabagism and alcoholism predominated in 8 and 6 patients respectively. Glottis was the localization and dysphony the paramount symptom. In the paper are emphasized the most important histologic features. Koilocytosis was present in 6 cases. Four patients developed a second tumor of epidermoid carcinoma type. No one exitus due to the verrucous growth. Only in 3 the death was attributed to the second malignancy. PMID:9199100

  3. Europe Unveils 20-Year Plan for Brilliant Future in Astronomy

    NASA Astrophysics Data System (ADS)

    2008-11-01

    Astronomy is enjoying a golden age of fundamental, exciting discoveries. Europe is at the forefront, thanks to 50 years of progress in cooperation. To remain ahead over the next two to three decades, Europe must prioritise and coordinate the investment of its financial and human resources even more closely. The ASTRONET network, backed by the entire European scientific community, supported by the European Commission, and coordinated by the CNRS, today presents its Roadmap for a brilliant future for European astronomy. ESO's European Extremely Large Telescope is ranked as one of two top-priority large ground-based projects. Astronet and the E-ELT ESO PR Photo 43a/08 The E-ELT Europe is a leader in astronomy today, with the world's most successful optical observatory, ESO's Very Large Telescope, and cutting-edge facilities in radio astronomy and in space. In an unprecedented effort demonstrating the potential of European scientific cooperation, all of European astronomy is now joining forces to define the scientific challenges for the future and construct a common plan to address them in a cost-effective manner. In 2007, a top-level Science Vision was prepared to assess the most burning scientific questions over the next quarter century, ranging from dark energy to life on other planets. European astronomy now presents its Infrastructure Roadmap, a comprehensive 20-year plan to coordinate national and community investments to meet these challenges in a cost-effective manner. The Roadmap not only prioritises the necessary new frontline research facilities from radio telescopes to planetary probes, in space and on the ground, but also considers such key issues as existing facilities, human resources, ICT infrastructure, education and outreach, and cost -- of operations as well as construction. This bold new initiative -- ASTRONET -- was created by the major European funding agencies with support from the European Commission and is coordinated by the National Institute

  4. Europe Unveils 20-Year Plan for Brilliant Future in Astronomy

    NASA Astrophysics Data System (ADS)

    2008-11-01

    Astronomy is enjoying a golden age of fundamental, exciting discoveries. Europe is at the forefront, thanks to 50 years of progress in cooperation. To remain ahead over the next two to three decades, Europe must prioritise and coordinate the investment of its financial and human resources even more closely. The ASTRONET network, backed by the entire European scientific community, supported by the European Commission, and coordinated by the CNRS, today presents its Roadmap for a brilliant future for European astronomy. ESO's European Extremely Large Telescope is ranked as one of two top-priority large ground-based projects. Astronet and the E-ELT ESO PR Photo 43a/08 The E-ELT Europe is a leader in astronomy today, with the world's most successful optical observatory, ESO's Very Large Telescope, and cutting-edge facilities in radio astronomy and in space. In an unprecedented effort demonstrating the potential of European scientific cooperation, all of European astronomy is now joining forces to define the scientific challenges for the future and construct a common plan to address them in a cost-effective manner. In 2007, a top-level Science Vision was prepared to assess the most burning scientific questions over the next quarter century, ranging from dark energy to life on other planets. European astronomy now presents its Infrastructure Roadmap, a comprehensive 20-year plan to coordinate national and community investments to meet these challenges in a cost-effective manner. The Roadmap not only prioritises the necessary new frontline research facilities from radio telescopes to planetary probes, in space and on the ground, but also considers such key issues as existing facilities, human resources, ICT infrastructure, education and outreach, and cost -- of operations as well as construction. This bold new initiative -- ASTRONET -- was created by the major European funding agencies with support from the European Commission and is coordinated by the National Institute

  5. Beyond the horizon

    SciTech Connect

    Einhorn, Martin B; Mahato, Manavendra

    2006-05-15

    Cosmic horizons arise in general relativity in the context of black holes and in certain cosmologies. Classically, regions beyond a horizon are inaccessible to causal observers. However, quantum mechanical correlations may exist across horizons that may influence local observations. For the case of de Sitter space, we show how a single particle excitation behind the horizon changes the density matrix governing local observables. As compared to the vacuum state, we calculate the change in the average energy and entropy per unit volume. This illustrates what may be a generic property allowing some features of spacetime beyond a horizon to be inferred.

  6. Hall scrambling on black hole horizons

    NASA Astrophysics Data System (ADS)

    Fischler, Willy; Kundu, Sandipan

    2015-08-01

    We explore the effect of the electrodynamics θ angle on the macroscopic properties of black hole horizons. Using only classical Einstein-Maxwell-Chern-Simons theory in (3 +1 ) dimensions, in the form of the membrane paradigm, we show that in the presence of the θ term, a black hole horizon behaves as a Hall conductor, for an observer hovering outside. We study how localized perturbations created on the stretched horizon scramble on the horizon by dropping a charged particle. We show that the θ angle affects the way perturbations scramble on the horizon, in particular, it introduces vortices without changing the scrambling time. This Hall scrambling of information is also expected to occur on cosmological horizons.

  7. Children's Rights and Youth Justice: 20 Years of No Progress

    ERIC Educational Resources Information Center

    Smith, Roger

    2010-01-01

    The adoption of the United Nations Convention on the Rights of the Child (UNCRC) in 1989 and its ratification by the UK government two years later came at a time of considerable progress in youth justice. The Convention itself set clear standards of treatment, in terms of both processes and disposals, which appeared at the time to provide positive…

  8. Finite-Horizon Near-Optimal Output Feedback Neural Network Control of Quantized Nonlinear Discrete-Time Systems With Input Constraint.

    PubMed

    Xu, Hao; Zhao, Qiming; Jagannathan, Sarangapani

    2015-08-01

    The output feedback-based near-optimal regulation of uncertain and quantized nonlinear discrete-time systems in affine form with control constraint over finite horizon is addressed in this paper. First, the effect of input constraint is handled using a nonquadratic cost functional. Next, a neural network (NN)-based Luenberger observer is proposed to reconstruct both the system states and the control coefficient matrix so that a separate identifier is not needed. Then, approximate dynamic programming-based actor-critic framework is utilized to approximate the time-varying solution of the Hamilton-Jacobi-Bellman using NNs with constant weights and time-dependent activation functions. A new error term is defined and incorporated in the NN update law so that the terminal constraint error is also minimized over time. Finally, a novel dynamic quantizer for the control inputs with adaptive step size is designed to eliminate the quantization error overtime, thus overcoming the drawback of the traditional uniform quantizer. The proposed scheme functions in a forward-in-time manner without offline training phase. Lyapunov analysis is used to investigate the stability. Simulation results are given to show the effectiveness and feasibility of the proposed method. PMID:25794403

  9. Finite-Horizon Near-Optimal Output Feedback Neural Network Control of Quantized Nonlinear Discrete-Time Systems With Input Constraint.

    PubMed

    Xu, Hao; Zhao, Qiming; Jagannathan, Sarangapani

    2015-08-01

    The output feedback-based near-optimal regulation of uncertain and quantized nonlinear discrete-time systems in affine form with control constraint over finite horizon is addressed in this paper. First, the effect of input constraint is handled using a nonquadratic cost functional. Next, a neural network (NN)-based Luenberger observer is proposed to reconstruct both the system states and the control coefficient matrix so that a separate identifier is not needed. Then, approximate dynamic programming-based actor-critic framework is utilized to approximate the time-varying solution of the Hamilton-Jacobi-Bellman using NNs with constant weights and time-dependent activation functions. A new error term is defined and incorporated in the NN update law so that the terminal constraint error is also minimized over time. Finally, a novel dynamic quantizer for the control inputs with adaptive step size is designed to eliminate the quantization error overtime, thus overcoming the drawback of the traditional uniform quantizer. The proposed scheme functions in a forward-in-time manner without offline training phase. Lyapunov analysis is used to investigate the stability. Simulation results are given to show the effectiveness and feasibility of the proposed method.

  10. Soil-geographical and ecological tour in West-Russia: 20 years anniversary

    NASA Astrophysics Data System (ADS)

    Kuzyakov, Yakov

    2013-04-01

    Soil-geographical and agro-ecological tour in Russia celebrated in this summer its 20 years anniversary! More than 800 students, PhD students and researcher from Germany, Switzerland, Austria, Sweden and France participated at the tour since 1993. The majority of the participants were students studying soil science, geoecology, geography, agriculture and ecology. The tour is based on a classical Russian zonal approach: a cross-section of climatic zones starting from south taiga, through deciduous forest, forest steppe, steppe, dry steppe, to semi dessert and transition to the desert zone. In each zone the specifics of climate, vegetation, nutrient cycling, and of course soil genesis as well as soil use by forestry and agriculture are described. Half of the soil group units of WRB classification (2006) are presented on about 35 soil profile pits and are described with focus on pedogenic processes and soil forming factors. The following soil groups are described in details by horizons according to WRB soil classification (2006): Arenosols, Podzols, Albeluvisols Histosols, Gleysols, Luvisols, Phaeozems, Chernozems, Kastanozems, Calcisols, Vertisols, Leptosols, Fluvisols, Solonetzes, Solonchaks. In addition to natural conditions, large-scale experiments designing agricultural landscapes (stone steppe), biosphere reserves and conservation areas (Tula-Schneisen, Divnogor'je, Baskunchak), as well as collective agricultural farms (previously kolkhoz) are visited to evaluate the anthropogenic effects on ecosystems and especially on soils. The 2.5 weeks bus journey through many villages and small towns, visits of museums and historical monuments, introduction in the settlement development of different regions provide a broad presentation of Russian history, traditions, life style, and contemporary state. So, combination of very diverse educational part focused on soil and environmental conditions with anthropogenic impacts and local history as well as recent socioeconomic

  11. 20 Years Later: Dynamics of the School-College Partnership

    ERIC Educational Resources Information Center

    Heimann, Revital

    2015-01-01

    This descriptive study examined the dynamics of partnership over time between a training school and a college of education. Its purpose was to provide a deeper understanding of the dynamics of collaboration within the context of the partnership between the school and the college. The dynamics of the changes occurring in this collaboration over a…

  12. Deepwater Horizon Situation Report #5

    SciTech Connect

    2010-06-10

    At approximately 11:00 pm EDT April 20, 2010 an explosion occurred aboard the Deepwater Horizon mobile offshore drilling unit (MODU) located 52 miles Southeast of Venice, LA and 130 miles southeast of New Orleans, LA. The MODU was drilling an exploratory well and was not producing oil at the time of the incident. The Deepwater Horizon MODU sank 1,500 feet northwest of the well site. Detailed information on response and recovery operations can be found at: http://www.deepwaterhorizonresponse.com/go/site/2931/

  13. Horizon Report: 2009 Economic Development Edition

    ERIC Educational Resources Information Center

    Johnson, L.; Levine, A.; Scott, C.; Smith, R.; Stone, S.

    2009-01-01

    The New Media Consortium's Horizon Project is an ongoing research project that seeks to identify and describe emerging technologies likely to have a large impact in education and other industries around the world over a five-year time period. The chief products of the project are the "Horizon Reports", an annual series of publications that…

  14. Project Horizon: How Utah Is Reducing Recidivism.

    ERIC Educational Resources Information Center

    Robinson, Daimar

    2000-01-01

    Project Horizon, Utah's statute to reduce the economic and social cost of recidivism, shifted funding for correctional education to the state education agency. Parolees who participated in Project Horizon had an 18-20 percent lower recidivism rate than nonparticipants and found post-release jobs 89 percent of the time. (JOW)

  15. Does time heal all wounds? Community attachment, natural resource employment, and health impacts in the wake of the BP Deepwater Horizon disaster.

    PubMed

    Cope, Michael R; Slack, Tim; Blanchard, Troy C; Lee, Matthew R

    2013-05-01

    On April 20, 2010, the BP-leased Deepwater Horizon (BP-DH) oil rig exploded, resulting in the largest marine oil spill in history. In this paper we utilize one-of-a-kind household survey data-the Louisiana Community Oil Spill Survey-to examine the impacts of the BP-DH disaster on the mental and physical health of spill affected residents in coastal Louisiana, with a special focus on the influence of community attachment and natural resource employment. We find that levels of both negative mental and physical health were significantly more pronounced at baseline compared to later time points. We show that greater community attachment is linked to lower levels of negative health impacts in the wake of the oil spill and that the disaster had a uniquely negative impact on households involved in the fishing industry. Further, we find evidence that the relationship between community attachment and mental health is more pronounced at later points in time, and that the negative health impacts on fishers have worsened over time. Implications for research and policy are discussed. PMID:23522000

  16. Pulmonary gas transfer 20 years after pneumonectomy for pulmonary tuberculosis.

    PubMed Central

    Gimeno, F; Kraan, J K; Orie, N G; Peset, R

    1977-01-01

    The changes in pulmonary function after pneumonectomy in 13 patients with pulmonary tuberculosis have been studied. The data at the time of two follow-up studies are compared with those obtained before the pneumonectomy. The first follow-up was carried out between 5 and 30 months postoperatively and the second between 20 and 24 years later. The results of this second follow-up show a relatively normal arterial oxygen saturation and gas transfer factor but an increased residual volume which cannot be explained by increasing age alone. PMID:841538

  17. The Pu'u 'O'o-Kupaianaha Eruption of Kilauea Volcano, Hawaii: The First 20 Years

    USGS Publications Warehouse

    Heliker, Christina C.; Swanson, Donald A.; Takahashi, Taeko Jane

    2003-01-01

    The Pu'u 'O'o-Kupaianaha eruption started on January 3, 1983. The ensuing 20-year period of nearly continuous eruption is the longest at Kilauea Volcano since the famous lava-lake activity of the 19th century. No rift-zone eruption in more than 600 years even comes close to matching the duration and volume of activity of these past two decades. Fortunately, such a landmark event came during a period of remarkable technological advancements in volcano monitoring. When the eruption began, the Global Positioning System (GPS) and the Geographic Information System (GIS) were but glimmers on the horizon, broadband seismology was in its infancy, and the correlation spectrometer (COSPEC), used to measure SO2 flux, was still very young. Now, all of these techniques are employed on a daily basis to track the ongoing eruption and construct models about its behavior. The 12 chapters in this volume, written by present or past Hawaiian Volcano Observatory staff members and close collaborators, celebrate the growth of understanding that has resulted from research during the past 20 years of Kilauea's eruption. The chapters range widely in emphasis, subject matter, and scope, but all present new concepts or important modifications of previous ideas - in some cases, ideas long held and cherished.

  18. 20 Years of Progress in Radiation Oncology: Prostate Cancer.

    PubMed

    Lanciano; Thomas; Eifel

    1997-04-01

    Carcinoma of the cervix remains of special interest to the Patterns of Care Study (PCS) because of the prominent role that radiotherapy plays in the definitive management of all stages and extents of disease. Five PCS surveys have been conducted for squamous cell cancer of the uterine cervix beginning in 1973 and repeated thereafter at 5-year intervals. The records of over 2,700 women have been reviewed for these surveys. Changes in the pretreatment investigations of cervical cancer patients have occurred during these years, with an increase in the use of computed tomography (CT) and a decrease in the use of intravenous pyelography and cystoscopy. A marked increase in the use of linear accelerators has also occurred, with 98% of all facilities having a linear accelerator as the highest energy treatment machine in the 1988 survey. There has been a change in brachytherapy prescription over the time of the surveys, with most institutions reporting point dose calculations and dose distributions instead of milligram hours. Mean point A dose has increased to approximately 80cGy, reflecting the PCS recommendations of dose intensity to the paracentral point through use of brachytherapy. The outcome for stage I and II cervical cancer has remained stable over the time of the surveys, while the results have improved for stage III disease. This improvement in survival and local control for stage III cervical cancer is due in part to the PCS, which has developed standards of treatment with the goal of radiation dose intensity. A number of patient, tumor, and treatment factors significant in multivariate analysis have been described by the PCS with large cohorts of patients. The most important treatment factors associated with a decrease in pelvic failure and improved survival are the use of brachytherapy and higher paracentral dose. A significant dose response has been described for stage III cervical cancer and optimal pelvic control has been demonstrated with point A doses

  19. Themes, Orientations, Synergies and a Shared Agenda: The First 20?Years of the SEDA Series of Books

    ERIC Educational Resources Information Center

    Pickford, Ruth; Brown, Sally

    2013-01-01

    Over 20?years, 25 books have been published to date in the SEDA series, and this review article aims to analyse the ways in which books within the series have contributed to thinking in higher education pedagogy over this time. We have approached the texts through three lenses, analysing them chronologically, thematically and by the orientation of…

  20. Trends in Avoidable Death over 20 Years in Korea

    PubMed Central

    Chung, Ji In; Choi, Ji Sook; Kim, Bo Mi

    2008-01-01

    To evaluate the achievement of health care services in Korea independent of other socioeconomic factors, we observed the time trend of avoidable death between 1983 and 2004. A list of avoidable causes of death was constructed based on the European Community Atlas of "Avoidable Death". We calculated sex- and age-standardized mortality rates of Korean aged 1-64 yr using data of the Korea National Statistical Office. The avoidable mortality rate (per 100,000 persons) decreased from 225 to 84 in men and from 122 to 41 in women. Accordingly, the proportion of avoidable deaths among all classifiable deaths was reduced by 8.1% in men and 6.4% in women. However, mortality rates from some preventable causes such as ischemic heart disease and malignant neoplasms of lung, breast, cervix, and colorectum have been on the rise. Mortality preventable by appropriate medical care showed the greatest reduction (by 77.8%), while the mortality preventable by primary prevention showed the least reduction (by 50.0%). These findings suggest that health care service has significantly contributed to the improvement of health in Korea. However, more effective intervention programs would be needed given the less reduction in mortality avoidable by primary or secondary prevention than expected and unexpectedly increasing mortality from several preventable causes. PMID:19119439

  1. 20 years of Black Carbon measurements in Germany

    NASA Astrophysics Data System (ADS)

    Kutzner, Rebecca; Quedenau, Jörn; Kuik, Friderike; von Schneidemesser, Erika; Schmale, Julia

    2016-04-01

    Black Carbon (BC) is an important short-lived climate-forcing pollutant contributing to global warming through absorption of sunlight. At the same time, BC, as a component of particulate matter (PM) exerts adverse health effects, like decreased lung function and exacerbated asthma. Globally, anthropogenic emission sources of BC include residential heating, transport, and agricultural fires, while the dominant natural emission sources are wildfires. Despite the various adverse effects of BC, legislation that requires mandatory monitoring of BC concentrations does not currently exist in the European Union. Instead, BC is only indirectly monitored as component of PM10 and PM2.5 (particulate matter with a diameter smaller 10 μm and 2.5 μm). Before the introduction of mandatory PM10 and PM2.5 monitoring in the European Union in 2005 and 2015, respectively, 'black smoke', a surrogate for BC, was a required measurement in Germany from the early 1990s. The annual mean limit value was 14 μg m-3 from 1995 and 8 μg m-3 from 1998 onwards. Many 'black smoke' measurements were stopped in 2004, with the repeal of the regulations obtaining at the time. However, in most German federal states a limited number BC monitoring stations continued to operate. Here we present a synthesis of BC data from 213 stations across Germany covering the period between 1994 and 2014. Due to the lack of a standardized method and respective legislation, the data set is very heterogeneous relying on twelve different measurement methods including chemical, optical, and thermal-optical methods. Stations include locations classified as background, urban-background, industrial and traffic among other types. Raw data in many different formats has been modelled and integrated in a relational database, allowing various options for further data analysis. We highlight results from the year 2009, as it is the year with the largest measurement coverage based on the same measurement method, with 30 stations. In

  2. Time- and Oil-Dependent Transcriptomic and Physiological Responses to Deepwater Horizon Oil in Mahi-Mahi (Coryphaena hippurus) Embryos and Larvae.

    PubMed

    Xu, Elvis Genbo; Mager, Edward M; Grosell, Martin; Pasparakis, Christina; Schlenker, Lela S; Stieglitz, John D; Benetti, Daniel; Hazard, E Starr; Courtney, Sean M; Diamante, Graciel; Freitas, Juliane; Hardiman, Gary; Schlenk, Daniel

    2016-07-19

    The Deepwater Horizon (DWH) oil spill contaminated the spawning habitats for numerous commercially and ecologically important fishes. Exposure to the water accommodated fraction (WAF) of oil from the spill has been shown to cause cardiac toxicity during early developmental stages across fishes. To better understand the molecular events and explore new pathways responsible for toxicity, RNA sequencing was performed in conjunction with physiological and morphological assessments to analyze the time-course (24, 48, and 96 h post fertilization (hpf)) of transcriptional and developmental responses in embryos/larvae of mahi-mahi exposed to WAF of weathered (slick) and source DWH oils. Slick oil exposure induced more pronounced changes in gene expression over time than source oil exposure. Predominant transcriptomic responses included alteration of EIF2 signaling, steroid biosynthesis, ribosome biogenesis and activation of the cytochrome P450 pathway. At 96 hpf, slick oil exposure resulted in significant perturbations in eye development and peripheral nervous system, suggesting novel targets in addition to the heart may be involved in the developmental toxicity of DHW oil. Comparisons of changes of cardiac genes with phenotypic responses were consistent with reduced heart rate and increased pericardial edema in larvae exposed to slick oil but not source oil. PMID:27348429

  3. Assessment of benthic changes during 20 years of monitoring the Mexican Salina Cruz Bay.

    PubMed

    González-Macías, C; Schifter, I; Lluch-Cota, D B; Méndez-Rodríguez, L; Hernández-Vázquez, S

    2009-02-01

    In this work a non-parametric multivariate analysis was used to assess the impact of metals and organic compounds in the macro infaunal component of the mollusks benthic community using surface sediment data from several monitoring programs collected over 20 years in Salina Cruz Bay, Mexico. The data for benthic mollusks community characteristics (richness, abundance and diversity) were linked to multivariate environmental patterns, using the Alternating Conditional Expectations method to correlate the biological measurements of the mollusk community with the physicochemical properties of water and sediments. Mollusks community variation is related to environmental characteristics as well as lead content. Surface deposit feeders are increasing their relative density, while subsurface deposit feeders are decreasing with respect to time, these last are expected to be more related with sediment and more affected then by its quality. However gastropods with predatory carnivore as well as chemosymbiotic deposit feeder bivalves have maintained their relative densities along time.

  4. [A glaucoma follow-up of 1500 persons over 20 years].

    PubMed

    Fitoussi, Y; Corbe, C; Hamard, H; Perdriel, G

    1988-01-01

    The parameters of glaucoma risk have been compiled and computer processed on 1,571 patients during 20 years at the C.P.E.M.P.N. (Medical Evaluation Center for the Aeronautic Staff) of Paris. The goal of this study is to follow in real time the évolution of these parameters and to determine their physiological variations across time in terms of age and professional categories. An average intra-ocular pressure of 15.1 mmHg as well as hypertonia and glaucoma percentages respectively of 3.88% and 0.6% have been recorded in this study. These results were below the results of other previous surveys due to the greater age range of our study the youngest being 15 years old. There was no significant difference among pilots and non pilots. The optic disc examination was not decisive for diagnostic screening.

  5. The 2010 Horizon Report

    ERIC Educational Resources Information Center

    Johnson, L.; Levine, A.; Smith, R.; Stone, S.

    2010-01-01

    The annual "Horizon Report" describes the continuing work of the New Media Consortium's Horizon Project, a qualitative research project established in 2002 that identifies and describes emerging technologies likely to have a large impact on teaching, learning, or creative inquiry on college and university campuses within the next five years. The…

  6. Two Horizons of Fusion

    ERIC Educational Resources Information Center

    Lo, Mun Ling; Chik, Pakey Pui Man

    2016-01-01

    In this paper, we aim to differentiate the internal and external horizons of "fusion." "Fusion" in the internal horizon relates to the structure and meaning of the object of learning as experienced by the learner. It clarifies the interrelationships among an object's critical features and aspects. It also illuminates the…

  7. Semiclassical ultraextremal horizons

    SciTech Connect

    Matyjasek, Jerzy; Zaslavskii, O.B.

    2005-04-15

    We examine backreaction of quantum massive fields on multiply-degenerate (ultraextremal) horizons. It is shown that, under influence of the quantum backreaction, the horizon of such a kind moves to a new position near which the metric does not change its asymptotics, so the ultraextremal black holes and cosmological spacetimes do exist as self-consistent solutions of the semiclassical field equations.

  8. Changes in plant species composition of coastal dune habitats over a 20-year period.

    PubMed

    Del Vecchio, Silvia; Prisco, Irene; Acosta, Alicia T R; Stanisci, Angela

    2015-01-01

    Coastal sandy ecosystems are increasingly being threatened by human pressure, causing loss of biodiversity, habitat degradation and landscape modifications. However, there are still very few detailed studies focussing on compositional changes in coastal dune plant communities over time. In this work, we investigated how coastal dune European Union (EU) habitats (from pioneer annual beach communities to Mediterranean scrubs on the landward fixed dunes) have changed during the last 20 years. Using phytosociological relevés conducted in 1989-90 and in 2010-12, we investigated changes in floristic composition over time. We then compared plant cover and the proportion of ruderal, alien and habitat diagnostic species ('focal species') in the two periods. Finally, we used Ellenberg indicator values to define the 'preferences' of the plant species for temperature and moisture. We found that only fore dune habitats showed significant differences in species cover between the two time periods, with higher plant cover in the more recent relevés and a significant increase in thermophilic species. Although previous studies have demonstrated consistent habitat loss in this area, we observed that all coastal dune plant communities remain well represented, after a 20-year period. However, fore dunes have been experiencing significant compositional changes. Although we cannot confirm whether the observed changes are strictly related to climatic changes, to human pressure or to both, we hypothesize that a moderate increment in average yearly temperature may have promoted the increase in plant cover and the spread of thermophilic species. Thus, even though human activities are major driving forces of change in coastal dune vegetation, at the community scale climatic factors may also play important roles. Our study draws on re-visitation studies which appear to constitute a powerful tool for the assessment of the conservation status of EU habitats. PMID:25750408

  9. Changes in plant species composition of coastal dune habitats over a 20-year period

    PubMed Central

    Del Vecchio, Silvia; Prisco, Irene; Acosta, Alicia T. R.; Stanisci, Angela

    2015-01-01

    Coastal sandy ecosystems are increasingly being threatened by human pressure, causing loss of biodiversity, habitat degradation and landscape modifications. However, there are still very few detailed studies focussing on compositional changes in coastal dune plant communities over time. In this work, we investigated how coastal dune European Union (EU) habitats (from pioneer annual beach communities to Mediterranean scrubs on the landward fixed dunes) have changed during the last 20 years. Using phytosociological relevés conducted in 1989–90 and in 2010–12, we investigated changes in floristic composition over time. We then compared plant cover and the proportion of ruderal, alien and habitat diagnostic species (‘focal species’) in the two periods. Finally, we used Ellenberg indicator values to define the ‘preferences’ of the plant species for temperature and moisture. We found that only fore dune habitats showed significant differences in species cover between the two time periods, with higher plant cover in the more recent relevés and a significant increase in thermophilic species. Although previous studies have demonstrated consistent habitat loss in this area, we observed that all coastal dune plant communities remain well represented, after a 20-year period. However, fore dunes have been experiencing significant compositional changes. Although we cannot confirm whether the observed changes are strictly related to climatic changes, to human pressure or to both, we hypothesize that a moderate increment in average yearly temperature may have promoted the increase in plant cover and the spread of thermophilic species. Thus, even though human activities are major driving forces of change in coastal dune vegetation, at the community scale climatic factors may also play important roles. Our study draws on re-visitation studies which appear to constitute a powerful tool for the assessment of the conservation status of EU habitats. PMID:25750408

  10. Geochemical and isotopic time series of oil deposited in Barataria Bay and on Grand Isle, Louisiana, after the Deepwater Horizon Oil Spill

    NASA Astrophysics Data System (ADS)

    Finkelstein, D. B.; Schimmelmann, A.; Rosenheim, B. E.

    2012-12-01

    We present time-series of bulk hydrocarbon geochemical and compound specific isotopic data of oiled and tarry sediment deposits from Grand Isle and Barataria Bay, Louisiana. Samples were taken between 46 days and 694 days after the Macondo well blowout, and analyzed for bulk hydrocarbon stable carbon and hydrogen isotope ratios, n-alkane and other organic molecular characteristics, ramped pyrolysis stable carbon ratios and radiocarbon content, and compound specific isotope analysis. Bulk and compound specific stable hydrogen isotopes point to slight 2H-enrichment attributable to water washing during transport to Grand Isle and Barataria Bay, followed by more subtle changes after deposition that depended in part on the wave energy available locally. Characterization of the n-alkane distributions through time identified subtle shifts in the dominant n-alkanes from water washing and terrestrial degradation. The loss of high molecular weight n-alkanes and an increase in the unresolved complex mixture after day 337 is consistent with a shift from slight to moderate biodegradation. More significant variations were observed in elemental H:C ratios, whereas bulk stable carbon isotope values showed small increases through time. Ramped pyrolysis analyses illustrated relatively volatile and reactive petroleum-derived components were present during the first year following the spill, but they ultimately became less apparent during later sampling. Isotope results from different ramped pyrolysis components are discussed. Compound specific isotope analysis indicate that a combination of variables (e.g., tidal water washing and biodegradation) may impact degradation during the first 200 days. This period was followed by a mixing of Macondo and non-Macondo hydrocarbons in the environment. In sum, our analyses show the complementary roles of abiotic and biotic factors in degradation of the Deepwater Horizon oil that was deposited in different environments of coastal Louisiana.

  11. Unintended compositional changes in genetically modified (GM) crops: 20 years of research.

    PubMed

    Herman, Rod A; Price, William D

    2013-12-01

    The compositional equivalency between genetically modified (GM) crops and nontransgenic comparators has been a fundamental component of human health safety assessment for 20 years. During this time, a large amount of information has been amassed on the compositional changes that accompany both the transgenesis process and traditional breeding methods; additionally, the genetic mechanisms behind these changes have been elucidated. After two decades, scientists are encouraged to objectively assess this body of literature and determine if sufficient scientific uncertainty still exists to continue the general requirement for these studies to support the safety assessment of transgenic crops. It is concluded that suspect unintended compositional effects that could be caused by genetic modification have not materialized on the basis of this substantial literature. Hence, compositional equivalence studies uniquely required for GM crops may no longer be justified on the basis of scientific uncertainty.

  12. Echoes of Bedford: a 20-year social psychology memoir on participatory action research hatched behind bars.

    PubMed

    Fine, Michelle

    2013-11-01

    Responding to Martin Luther King Jr.'s 1968 address at the American Psychological Association calling for a psychology that would educate Whites about racial injustice, this article challenges the widening epistemological gap between those who suffer from inequality and those who conduct social policy research on inequality. In this 20-year memoir on the echoes of a single piece of participatory policy research, Changing Minds: The Impact of College in a Maximum-Security Prison (Fine et al., 2001), readers are invited to explore how deep critical participation by a collaborative team of university and prisoner researchers has facilitated theoretical and methodological complexity, enhanced contextual and construct validity, thickened commitments to ethics and action, and fueled the political sustainability and generalizability of the findings over time and space.

  13. Echoes of Bedford: a 20-year social psychology memoir on participatory action research hatched behind bars.

    PubMed

    Fine, Michelle

    2013-11-01

    Responding to Martin Luther King Jr.'s 1968 address at the American Psychological Association calling for a psychology that would educate Whites about racial injustice, this article challenges the widening epistemological gap between those who suffer from inequality and those who conduct social policy research on inequality. In this 20-year memoir on the echoes of a single piece of participatory policy research, Changing Minds: The Impact of College in a Maximum-Security Prison (Fine et al., 2001), readers are invited to explore how deep critical participation by a collaborative team of university and prisoner researchers has facilitated theoretical and methodological complexity, enhanced contextual and construct validity, thickened commitments to ethics and action, and fueled the political sustainability and generalizability of the findings over time and space. PMID:24320653

  14. Pustular psoriasis in childhood and adolescence: a 20-year single-center experience.

    PubMed

    Popadic, Svetlana; Nikolic, Milos

    2014-01-01

    Pustular psoriasis (PP) is rare in children. The small number of reported cases makes deciding on treatment and follow-up challenging. The current study was an evaluation of treatment approaches and courses of PP in 18 children diagnosed and followed over a 20-year period. From 1992 to 2011 we treated 1,447 children with psoriasis, 18 of whom had PP. Follow-up was 2 to 19 years. At the time of initial manifestation of PP, our patients were 1.5 months to 16 years old. Seven patients had a previous history of psoriasis vulgaris. Three children entered long-term remission after one pustular attack, 10 developed psoriasis vulgaris, 2 are currently under treatment, and 3 were lost to follow-up. Treatment with acitretin, cyclosporine, or methotrexate was efficacious and well tolerated. PP is rare, but according to our experience, it has a good prognosis in children.

  15. Zollinger-Ellison syndrome. Spontaneous regression of advanced intra-abdominal metastases with 20 year survival.

    PubMed Central

    Davis, C E; Vansant, J H

    1979-01-01

    A 35-year-old man with the Zollinger-Ellison syndrome who is alive and well 20 years following diagnosis at age 15, is represented. At the initial operation for a bleeding duodenal ulcer a ZE tumor of the pancreas also was excised. After two additional ineffective ulcer operations, total gastrectomy was performed. At that time, retroperitoneal and peripancreatic metastases were noted, and several were removed. Three years later at laparotomy, extensive hepatic metastases were biopsied as well. Spontaneous remission occurred and when re-explored at age 34, after 14 years, no metastases were identifiable in any area. The serum gastrin level has remained elevated, casting doubt upon its value as a criterion for evaluation of tumor recurrence or activity. Other additional interesting aspects are discussed. The importance of elimination of the acid-secreting cells by total gastrectomy is emphasized. The patient remains well. Images Fig. 1. Fig. 3. Fig. 4. PMID:443914

  16. Pharmacogenetics research on chemotherapy resistance in colorectal cancer over the last 20 years

    PubMed Central

    Panczyk, Mariusz

    2014-01-01

    During the past two decades the first sequencing of the human genome was performed showing its high degree of inter-individual differentiation, as a result of large international research projects (Human Genome Project, the 1000 Genomes Project International HapMap Project, and Programs for Genomic Applications NHLBI-PGA). This period was also a time of intensive development of molecular biology techniques and enormous knowledge growth in the biology of cancer. For clinical use in the treatment of patients with colorectal cancer (CRC), in addition to fluoropyrimidines, another two new cytostatic drugs were allowed: irinotecan and oxaliplatin. Intensive research into new treatment regimens and a new generation of drugs used in targeted therapy has also been conducted. The last 20 years was a time of numerous in vitro and in vivo studies on the molecular basis of drug resistance. One of the most important factors limiting the effectiveness of chemotherapy is the primary and secondary resistance of cancer cells. Understanding the genetic factors and mechanisms that contribute to the lack of or low sensitivity of tumour tissue to cytostatics is a key element in the currently developing trend of personalized medicine. Scientists hope to increase the percentage of positive treatment response in CRC patients due to practical applications of pharmacogenetics/pharmacogenomics. Over the past 20 years the clinical usability of different predictive markers has been tested among which only a few have been confirmed to have high application potential. This review is a synthetic presentation of drug resistance in the context of CRC patient chemotherapy. The multifactorial nature and volume of the issues involved do not allow the author to present a comprehensive study on this subject in one review. PMID:25110414

  17. Climate correlates of 20 years of trophic changes in a high-elevation riparian system

    USGS Publications Warehouse

    Martin, T.E.

    2007-01-01

    The consequences of climate change for ecosystem structure and function remain largely unknown. Here, I examine the ability of climate variation to explain long-term changes in bird and plant populations, as well as trophic interactions in a high-elevation riparian system in central Arizona, USA, based on 20 years of study. Abundances of dominant deciduous trees have declined dramatically over the 20 years, correlated with a decline in overwinter snowfall. Snowfall can affect overwinter presence of elk, whose browsing can significantly impact deciduous tree abundance. Thus, climate may affect the plant community indirectly through effects on herbivores, but may also act directly by influencing water availability for plants. Seven species of birds were found to initiate earlier breeding associated with an increase in spring temperature across years. The advance in breeding time did not affect starvation of young or clutch size. Earlier breeding also did not increase the length of the breeding season for single-brooded species, but did for multi-brooded species. Yet, none of these phenology-related changes was associated with bird population trends. Climate had much larger consequences for these seven bird species by affecting trophic levels below (plants) and above (predators) the birds. In particular, the climate-related declines in deciduous vegetation led to decreased abundance of preferred bird habitat and increased nest predation rates. In addition, summer precipitation declined over time, and drier summers also were further associated with greater nest predation in all species. The net result was local extinction and severe population declines in some previously common bird species, whereas one species increased strongly in abundance, and two species did not show clear population changes. These data indicate that climate can alter ecosystem structure and function through complex pathways that include direct and indirect effects on abundances and interactions

  18. Climate correlates of 20 years of trophic changes in a high-elevation riparian system.

    PubMed

    Martin, Thomas E

    2007-02-01

    The consequences of climate change for ecosystem structure and function remain largely unknown. Here, I examine the ability of climate variation to explain long-term changes in bird and plant populations, as well as trophic interactions in a high-elevation riparian system in central Arizona, USA, based on 20 years of study. Abundances of dominant deciduous trees have declined dramatically over the 20 years, correlated with a decline in overwinter snowfall. Snowfall can affect overwinter presence of elk, whose browsing can significantly impact deciduous tree abundance. Thus, climate may affect the plant community indirectly through effects on herbivores, but may also act directly by influencing water availability for plants. Seven species of birds were found to initiate earlier breeding associated with an increase in spring temperature across years. The advance in breeding time did not affect starvation of young or clutch size. Earlier breeding also did not increase the length of the breeding season for single-brooded species, but did for multi-brooded species. Yet, none of these phenology-related changes was associated with bird population trends. Climate had much larger consequences for these seven bird species by affecting trophic levels below (plants) and above (predators) the birds. In particular, the climate-related declines in deciduous vegetation led to decreased abundance of preferred bird habitat and increased nest predation rates. In addition, summer precipitation declined over time, and drier summers also were further associated with greater nest predation in all species. The net result was local extinction and severe population declines in some previously common bird species, whereas one species increased strongly in abundance, and two species did not show clear population changes. These data indicate that climate can alter ecosystem structure and function through complex pathways that include direct and indirect effects on abundances and interactions

  19. Pharmacogenetics research on chemotherapy resistance in colorectal cancer over the last 20 years.

    PubMed

    Panczyk, Mariusz

    2014-08-01

    During the past two decades the first sequencing of the human genome was performed showing its high degree of inter-individual differentiation, as a result of large international research projects (Human Genome Project, the 1000 Genomes Project International HapMap Project, and Programs for Genomic Applications NHLBI-PGA). This period was also a time of intensive development of molecular biology techniques and enormous knowledge growth in the biology of cancer. For clinical use in the treatment of patients with colorectal cancer (CRC), in addition to fluoropyrimidines, another two new cytostatic drugs were allowed: irinotecan and oxaliplatin. Intensive research into new treatment regimens and a new generation of drugs used in targeted therapy has also been conducted. The last 20 years was a time of numerous in vitro and in vivo studies on the molecular basis of drug resistance. One of the most important factors limiting the effectiveness of chemotherapy is the primary and secondary resistance of cancer cells. Understanding the genetic factors and mechanisms that contribute to the lack of or low sensitivity of tumour tissue to cytostatics is a key element in the currently developing trend of personalized medicine. Scientists hope to increase the percentage of positive treatment response in CRC patients due to practical applications of pharmacogenetics/pharmacogenomics. Over the past 20 years the clinical usability of different predictive markers has been tested among which only a few have been confirmed to have high application potential. This review is a synthetic presentation of drug resistance in the context of CRC patient chemotherapy. The multifactorial nature and volume of the issues involved do not allow the author to present a comprehensive study on this subject in one review.

  20. Prediction of the 20-year incidence of diabetes in older Chinese

    PubMed Central

    Liu, Xiangtong; Fine, Jason Peter; Chen, Zhenghong; Liu, Long; Li, Xia; Wang, Anxin; Guo, Jin; Tao, Lixin; Mahara, Gehendra; Tang, Zhe; Guo, Xiuhua

    2016-01-01

    Abstract The competing risk method has become more acceptable for time-to-event data analysis because of its advantage over the standard Cox model in accounting for competing events in the risk set. This study aimed to construct a prediction model for diabetes using a subdistribution hazards model. We prospectively followed 1857 community residents who were aged ≥ 55 years, free of diabetes at baseline examination from August 1992 to December 2012. Diabetes was defined as a self-reported history of diabetes diagnosis, taking antidiabetic medicine, or having fasting plasma glucose (FPG) ≥ 7.0 mmol/L. A questionnaire was used to measure diabetes risk factors, including dietary habits, lifestyle, psychological factors, cognitive function, and physical condition. Gray test and a subdistribution hazards model were used to construct a prediction algorithm for 20-year risk of diabetes. Receiver operating characteristic (ROC) curves, bootstrap cross-validated Wolber concordance index (C-index) statistics, and calibration plots were used to assess model performance. During the 20-year follow-up period, 144 cases were documented for diabetes incidence with a median follow-up of 10.9 years (interquartile range: 8.0–15.3 years). The cumulative incidence function of 20-year diabetes incidence was 11.60% after adjusting for the competing risk of nondiabetes death. Gray test showed that body mass index, FPG, self-rated heath status, and physical activity were associated with the cumulative incidence function of diabetes after adjusting for age. Finally, 5 standard risk factors (poor self-rated health status [subdistribution hazard ratio (SHR) = 1.73, P = 0.005], less physical activity [SHR = 1.39, P = 0.047], 55–65 years old [SHR = 4.37, P < 0.001], overweight [SHR = 2.15, P < 0.001] or obesity [SHR = 1.96, P = 0.003], and impaired fasting glucose [IFG] [SHR = 1.99, P < 0.001]) were significantly associated with incident

  1. Detection and Clinical Significance of Circulating Tumor Cells in Colorectal Cancer—20 Years of Progress

    PubMed Central

    Hardingham, Jennifer E; Grover, Phulwinder; Winter, Marnie; Hewett, Peter J; Price, Timothy J; Thierry, Benjamin

    2015-01-01

    Circulating tumor cells (CTC) may be defined as tumor- or metastasis-derived cells that are present in the bloodstream. The CTC pool in colorectal cancer (CRC) patients may include not only epithelial tumor cells, but also tumor cells undergoing epithelial–mesenchymal transition (EMT) and tumor stem cells. A significant number of patients diagnosed with early stage CRC subsequently relapse with recurrent or metastatic disease despite undergoing “curative” resection of their primary tumor. This suggests that an occult metastatic disease process was already underway, with viable tumor cells being shed from the primary tumor site, at least some of which have proliferative and metastatic potential and the ability to survive in the bloodstream. Such tumor cells are considered to be responsible for disease relapse in these patients. Their detection in peripheral blood at the time of diagnosis or after resection of the primary tumor may identify those early-stage patients who are at risk of developing recurrent or metastatic disease and who would benefit from adjuvant therapy. CTC may also be a useful adjunct to radiological assessment of tumor response to therapy. Over the last 20 years many approaches have been developed for the isolation and characterization of CTC. However, none of these methods can be considered the gold standard for detection of the entire pool of CTC. Recently our group has developed novel unbiased inertial microfluidics to enrich for CTC, followed by identification of CTC by imaging flow cytometry. Here, we provide a review of progress on CTC detection and clinical significance over the last 20 years. PMID:26605644

  2. The New 20-Year Global Precipitation Climatology Project (GPCP) Merged Satellite and Rainguage Monthly Analysis

    NASA Technical Reports Server (NTRS)

    Adler, Robert; Huffman, George; Xie, Ping Ping; Rudolf, Bruno; Gruber, Arnold; Janowiak, John

    1999-01-01

    A new 20-year, monthly, globally complete precipitation analysis has been completed as part of the World Climate Research Program's (WCRP/GEWEX) Global Precipitation Climatology Project (GPCP). This Version 2 of the community generated data set is a result of combining the procedures and data sets as described. The global, monthly, 2.5x 2.5 degree latitude-longitude product utilizes precipitation estimates from low-orbit microwave sensors (SSM/1) and geosynchronous IR sensors and raingauge information over land. The low-orbit microwave estimates are used to adjust or correct the geosynchronous IR estimates, thereby maximizing the utility of the more physically-based microwave estimates and the finer time sampling of the geosynchronous observations. Information from raingauges is blended into the analyses over land. In the 1986-present period TOVS-based precipitation estimates are adjusted to GPCP fields and used in polar regions to produce globally-complete results. The extension back to 1979 utilizes the procedures of Xie and Arkin and their OLR Precipitation Index (OPI). The 20-year climatology of the Version 2 GPCP analysis indicates the expected features of a very strong Pacific Ocean ITCZ and SPCZ with maximum 20-year means approaching 10 mm/day. A similar strength maximum over land is evident over Borneo. Weaker maxima in the tropics occur in the Atlantic ITCZ and over South America and Africa. In mid-latitudes of the Northern Hemisphere the Western Pacific and Western Atlantic maxima have values of approximately 7 mm/day, while in the Southern Hemisphere the mid-latitude maxima are located southeast of Africa, in mid-Pacific as an extension of the SPCZ and southeast of South America. In terms of global totals the GPCP analysis shows 2.7 mm/day (3.0 mm/day over ocean; 2.1 mm/day over land), similar to the Jaeger climatology, but not other climatologies. Zonal averages peak at 6 mm/day at 7*N with mid-latitude peaks of about 3 mm/day at 40-45* latitude

  3. Parity horizons in shape dynamics

    NASA Astrophysics Data System (ADS)

    Herczeg, Gabriel

    2016-11-01

    I introduce the notion of a parity horizon, and show that many simple solutions of shape dynamics possess them. I show that the event horizons of the known asymptotically flat black hole solutions of shape dynamics are parity horizons and that this notion of parity implies that these horizons possess a notion of CPT invariance that can in some cases be extended to the solution as a whole. I present three new solutions of shape dynamics with parity horizons and find that not only do event horizons become parity horizons in shape dynamics, but observer-dependent horizons and Cauchy horizons do as well. The fact that Cauchy horizons become (singular) parity horizons suggests a general chronology protection mechanism in shape dynamics that prevents the formation of closed timelike curves.

  4. New Horizons at Pluto

    NASA Astrophysics Data System (ADS)

    Schenk, Paul; Nimmo, Francis

    2016-06-01

    The New Horizons mission has revealed Pluto and its moon Charon to be geologically active worlds. The familiar, yet exotic, landforms suggest that geologic processes operate similarly across the Solar System, even in its cold outer reaches.

  5. An unusual cause of fitting in a 20 year old girl.

    PubMed

    Beckett, Daniel; Malins, A; Watson, M L; Kelly, C A

    2006-01-01

    Native renal artery stenosis resulting in hypertensive encephalopathy is exceptionally rare, with only 3 previous case reports in adults. We report such a case in a previously well 20 year old female.

  6. Multilevel learning in the adaptive management of waterfowl harvests: 20 years and counting

    USGS Publications Warehouse

    Johnson, Fred A.; Boomer, G. Scott; Williams, Byron K.; Nichols, James D.; Case, David J.

    2015-01-01

    In 1995, the U.S. Fish and Wildlife Service implemented an adaptive harvest management program (AHM) for the sport harvest of midcontinent mallards (Anas platyrhynchos). The program has been successful in reducing long-standing contentiousness in the regulatory process, while integrating science and policy in a coherent, rigorous, and transparent fashion. After 20 years, much has been learned about the relationship among waterfowl populations, their environment, and hunting regulations, with each increment of learning contributing to better management decisions. At the same time, however, much has been changing in the social, institutional, and environmental arenas that provide context for the AHM process. Declines in hunter numbers, competition from more pressing conservation issues, and global-change processes are increasingly challenging waterfowl managers to faithfully reflect the needs and desires of stakeholders, to account for an increasing number of institutional constraints, and to (probabilistically) predict the consequences of regulatory policy in a changing environment. We review the lessons learned from the AHM process so far, and describe emerging challenges and ways in which they may be addressed. We conclude that the practice of AHM has greatly increased an awareness of the roles of social values, trade-offs, and attitudes toward risk in regulatory decision-making. Nevertheless, going forward the waterfowl management community will need to focus not only on the relationships among habitat, harvest, and waterfowl populations, but on the ways in which society values waterfowl and how those values can change over time

  7. Orthodontic treatment need, outcome and residual treatment need in 15- and 20-year-olds.

    PubMed

    Bjerklin, Krister; Lindsten, Rune; Tunge, Jannicke Sagevik; Sjövall, Christine

    2012-01-01

    The aim of the study was to investigate orthodontic treatment need and the outcome of orthodontic treatment in 15-, and 20-year-olds in Jönköping, Sweden, with special reference to residual treatment need. An offer to participate in a clinical investigation was extended to random samples of 130 15-year-olds and 130 20-year-olds. Ninety-six of the 15-year-olds (73.3%; 45 boys and 51 girls) and 82 of the 20-year-olds (62.6%; 47 males and 35 females) accepted and presented for examination The participants filled in a questionnaire and impressions were taken for study models, which were graded according to the ICON index. In all, 39 (40.6%) of the 15-year-olds and 38 (46.3%) of the 20-year-olds had undergone or were currently undergoing orthodontic treatment. Ninety-one per cent of the 15-year-olds and 84% of the 20-year-olds considered that the orthodontic treatment goals had been fully or almost fully attained. Two of the 15-year-olds and two of the 20-year-olds currently wanted orthodontic treatment. This indicates a residual treatment demand of about 2%.

  8. Hydrographic changes during 20 years in the brine-filled basins of the Red Sea

    NASA Astrophysics Data System (ADS)

    Anschutz, Pierre; Blanc, Gérard; Chatin, Fabienne; Geiller, Magali; Pierret, Marie-Claire

    1999-10-01

    Many of the deep basins filled by hot brines in the Red Sea have not been investigated since their discovery in the early 1970s. Twenty years later, in September 1992, six of these deeps were revisited. The temperature and salinity of the Suakin, Port Sudan, Chain B, and Nereus deeps ranged from 23.25 to 44.60°C and from 144 to 270‰. These values were approximately the same in 1972, indicating that the budget of heat and salt was quite balanced. We measured strong gradients of properties in the transition zone between brines and overlying seawater. The contribution of salinity to the density gradient was more than one order of magnitude higher than the opposite contribution of temperature across the seawater-brine interface. Therefore the interface was extemely stable, and the transfer of properties across it was considered to be controlled mostly by molecular diffusion. We calculate that the diffusional transport of salt from the brines to seawater cannot affect significantly the salinity of the brines over a 20 year period, which agrees with the observations. The brine pools can persist for centuries with no salt input. Therefore, the persisence of brines does not correspond to a steady balance between diffusional loss and continuous input of hydrothermal solutions. Deeps that experience only episodical hydrothermal brine supplies may persist for a long time with salt inherited from past inputs. The theoretical loss of heat by diffusion from the brine to seawater was higher than the observed decrease in temperature of the brine pool during the 20 year period of observation. We calculated that the heat flux out of the pools into the overlying seawater was compensated by a heat flux into the pools of about 250-600 mW/m 2. This range of values corresponds to bottom heat flow values that have been reported earlier for the axial zone of the Red Sea. In contrast to the other brine pools, the temperature and salinity of the Valdivia Deep brine increased by 4.1°C and

  9. Global Patterns of Precipitation Anomalies Related to ENSO as Determined by the 20-Year GPCP Analysis

    NASA Technical Reports Server (NTRS)

    Adler, Robert; Curtis, Scott; Huffman, George; Bolvin, Dave; Einaudi, Franco (Technical Monitor)

    2000-01-01

    The new 20-year, monthly, globally complete precipitation analysis of the Global Precipitation Climatology Project (GPCP) is used to analyze ENSO-related precipitation anomalies over the globe. This Version 2 of the community generated data set is global, monthly, at 2.5 deg x 2.5 deg latitude-longitude resolution and utilizes precipitation estimates from low-orbit microwave sensors (SSM/I) and geosynchronous IR sensors and raingauge information over land. In the 1987-present period the low-orbit microwave (SSM/I) estimates are used to adjust or correct the geosynchronous IR estimates, thereby maximizing the utility of the more physically-based microwave estimates and the finer time sampling of the geosynchronous observations. Information from raingauges is blended into the analyses over land. The extension back to 1979 utilizes the OLR Precipitation Index (OPI) for the satellite component. An ENSO Precipitation Index (ESPI) using gradients of precipitation anomalies in the Maritime-Continent/Pacific Ocean region is used to define El Nino/La Nina months during the 20-year record. Mean anomalies for El Nino and La Nina are examined along with variations with respect to season and for individual events. The El Nino and La Nina mean anomalies are near mirror images of each other and when combined produce an ENSO signal with significant spatial continuity over large distances. This El Nino minus La Nina standardized precipitation anomaly map shows the usual positive anomaly over the central and eastern Pacific Ocean with the negative anomaly over the maritime continent along with an additional negative anomaly over Brazil and the Atlantic Ocean extending into Africa and a positive anomaly over the Horn of Africa and the western Indian Ocean. From these features along the Equator narrow positive and negative anomalies extend into middle latitudes in a V-shaped pattern open to the East as described by previous investigators. A number of the features are shown to continue

  10. Comparison of Cardiovascular Risk Factors in Different Areas of Health Care Over a 20-Year Period

    PubMed Central

    Jardim, Thiago Veiga; Sousa, Ana Luiza Lima; Povoa, Thais Rolim; Barroso, Weimar Sebba; Chinem, Brunela; Jardim, Paulo Cesar Veiga

    2014-01-01

    Background Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Knowledge about cardiovascular risk factors (CVRFs) in young adults and their modification over time are measures that change the risks and prevent CVDs. Objectives To determine the presence of CVRFs and their changes in different health care professionals over a period of 20 years. Methods All students of medicine, nursing, nutrition, odontology, and pharmacy departments of Federal University of Goiás who agreed to participate in this study were evaluated when they started their degree courses and 20 years afterward. Questionnaires on CVRFs [systemic arterial hypertension (SAH), diabetes mellitus, dyslipidemia, and family history of early CVD, smoking, alcohol consumption, and sedentarism] were administered. Cholesterol levels, blood sugar levels, blood pressure, weight, height, and body mass index were determined. The Kolmogorov-Smirnov test was used to evaluate distribution, the chi-square test was used to compare different courses and sexes, and the McNemar test was used for comparing CVRFs. The significance level was set at a p value of < 0.05. Results The first stage of the study included 281 individuals (91% of all the students), of which 62.9% were women; the mean age was 19.7 years. In the second stage, 215 subjects were reassessed (76% of the initial sample), of which 59.07% were women; the mean age was 39.8 years. The sample mostly consisted of medical students (with a predominance of men), followed by nursing, nutrition, and pharmacy students, with a predominance of women (p < 0.05). Excessive weight gain, SAH, and dyslipidemia were observed among physicians and dentists (p < 0.05). Excessive weight gain and SAH and a reduction in sedentarism (p < 0.05) were observed among pharmacists. Among nurses there was an increase in excessive weight and alcohol consumption (p < 0.05). Finally, nutritionists showed an increase in dyslipidemia (p < 0.05). Conclusion In general

  11. Firewall or smooth horizon?

    NASA Astrophysics Data System (ADS)

    Ori, Amos

    2016-01-01

    Almheiri, Marolf, Polchinski, and Sully pointed out that for a sufficiently old black hole (BH), the set of assumptions known as the complementarity postulates appears to be inconsistent with the assumption of local regularity at the horizon. They concluded that the horizon of an old BH is likely to be the locus of local irregularity, a "firewall". Here I point out that if one adopts a different assumption, namely that semiclassical physics holds throughout its anticipated domain of validity, then the inconsistency is avoided, and the horizon retains its regularity. In this alternative view-point, the vast portion of the original BH information remains trapped inside the BH throughout the semiclassical domain of evaporation, and possibly leaks out later on. This appears to be an inevitable outcome of semiclassical gravity (if assumed to apply throughout its anticipated domain of validity).

  12. Infrared variability of three hot stars on a time scale of 10-20 years

    NASA Astrophysics Data System (ADS)

    Taranova, O. G.; Shenavrin, V. I.

    2015-03-01

    Long-term (1994-2014) near-infrared observations of P Cyg, kDra, and BUTau are analyzed. It is shown that the observed brightness and color variations in P Cyg and k Dra can be explained by variations in the parameters of the stars themselves and their ionized circumstellar shells, whose excitation requires from 5 to 15% of the star's luminosity. The emission from BU Tau in the range 1.25-3.5 µm mimics blackbody radiation, and its variability is a consequence of variations in the star's temperature and, as a result, its radius and luminosity. No excess emission from BU Tau that could be associated with an additional source has been detected.

  13. Gravitational memory charges of supertranslation and superrotation on Rindler horizons

    NASA Astrophysics Data System (ADS)

    Hotta, Masahiro; Trevison, Jose; Yamaguchi, Koji

    2016-10-01

    In a Rindler-type coordinate system spanned in a region outside of a black hole horizon, we have nonvanishing classical holographic charges as soft hairs on the horizon for stationary black holes. Taking a large black hole mass limit, the spacetimes with the charges are described by asymptotic Rindler metrics. We construct a general theory of gravitational holographic charges for a (1 +3 )-dimensional linearized gravity field in the Minkowski background with Rindler horizons. Although matter crossing a Rindler horizon causes horizon deformation and a time-dependent coordinate shift—that is, gravitational memory—the supertranslation and superrotation charges on the horizon can be defined during and after its passage through the horizon. It is generally proven that holographic states on the horizon cannot store any information about absorbed perturbative gravitational waves. However, matter crossing the horizon really excites holographic states. By using gravitational memory operators, which consist of the holographic charge operators, we suggest a resolution of the no-cloning paradox of quantum information between matter falling into the horizon and holographic charges on the horizon from the viewpoint of the contextuality of quantum measurement.

  14. Termite (order Blattodea, infraorder Isoptera) baiting 20 years after commercial release.

    PubMed

    Evans, Theodore A; Iqbal, Naeem

    2015-07-01

    Termite baiting is now one of the two main management tools in developed countries after 20 years of commercial release. It has two main goals: to use small amounts of active ingredient and 'colony elimination', i.e. death of all individuals in the colony. We consider how well baiting has been evaluated from 100 studies in the scientific literature. Studies have included 15 active ingredients, 23 termite species and 16 countries, yet most studies have focused on the chitin synthesis inhibitor hexaflumuron, Reticulitermes and the United States. Baiting has mostly met its goals: typically about 0.5 g of active ingredient was used, and colony elimination achieved, albeit with rates varying from 0 to 100%, and sometimes supplemented with liquid insecticide. Baiting was most successful using chitin synthesis inhibitors against Reticulitermes and Coptotermes (Rhinotermitidae), in temperate locations, although colony elimination was usually inferred indirectly - mostly by termite absence from baits - and was often slow, from 25 to 450 days. Baiting has been less tested and less successful against higher termites in tropical locations, where they are most diverse and abundant. Future research may have to consider greater termite species diversity and other active ingredients to reduce control times in order to fulfil the potential of baiting. PMID:25244627

  15. The evolution of complementary and alternative medicine (CAM) in the USA over the last 20 years.

    PubMed

    Jonas, Wayne B; Eisenberg, David; Hufford, David; Crawford, Cindy

    2013-01-01

    Medical practices that reside outside the mainstream medical structures have existed for centuries, often waxing and waning in prominence and use for various reasons. Recently, there has been a resurgence in interest and use of such practices in the USA generally referred to under the label of 'complementary and alternative medicine' (CAM). In this article we summarize some of the highlight events that punctuated this resurgence over the last 20 years. As in the past, social forces affecting these trends circulate around power, resources, and scope of practice. However, a prominent feature of this dynamic is a discussion about the role of science and 'evidence-based medicine' in addressing pluralistic healthcare-related practices. In the early years of this period, attempts to formulate the place of CAM practices as they relate to epistemology, nonconventional assumptions about health and healing, and the complexity of understanding 'whole systems' were discussed and often examined. Less attention is being paid to those core assumptions in more recent times. The focus now seems to be on how CAM practices can be judiciously and effectively 'integrated' into mainstream medicine. Examples of how this dynamic is evolving are described.

  16. Tobacco interests or the public interest: 20 years of industry strategies to undermine airline smoking restrictions

    PubMed Central

    Lopipero, Peggy Ann; Bero, Lisa A

    2006-01-01

    Objectives To understand the evolution of 20 years of tobacco industry strategies to undermine federal restrictions of smoking on aircraft in the United States. Design We searched and analysed internal tobacco industry records, public documents, and other related research. Results The industry viewed these restrictions as a serious threat to the social acceptability of smoking. Its initial efforts included covert letter‐writing campaigns and lobbying of the airline industry, but with the emergence of proposals to ban smoking, the tobacco companies engaged in ever increasing efforts to forestall further restrictions. Tactics to dominate the public record became especially rigorous. The industry launched an aggressive public relations campaign that began with the promotion of industry sponsored petition drives and public opinion surveys. Results from polling research that produced findings contrary to the industry's position were suppressed. In order to demonstrate smoker outrage against a ban, later efforts included the sponsorship of smokers' rights and other front groups. Congressional allies and industry consultants sought to discredit the science underlying proposals to ban smoking and individual tobacco companies conducted their own cabin air quality research. Faced with the potential of a ban on all domestic flights, the industry sought to intimidate an air carrier and a prominent policymaker. Despite the intensification of tactics over time, including mobilisation of an army of lobbyists and Congressional allies, the tobacco industry was ultimately defeated. Conclusions Our longitudinal analysis provides insights into how and when the industry changed its plans and provides public health advocates with potential counterstrategies. PMID:16885582

  17. Implant survival and radiographic outcome of total hip replacement in patients less than 20 years old

    PubMed Central

    Tsukanaka, Masako; Halvorsen, Vera; Nordsletten, Lars; EngesæTer, Ingvild Ø; EngesæTer, Lars B; Marie Fenstad, Anne; Röhrl, Stephan M

    2016-01-01

    Background and purpose Total hip replacement (THR) is not recommended for children and very young teenagers because early and repetitive revisions are likely. We investigated the clinical and radiographic outcomes of THR performed in children and teenage patients. Patients and methods We included 111 patients (132 hips) who underwent THR before 20 years of age. They were identified in the Norwegian Arthroplasty Register, together with information on the primary diagnosis, types of implants, and any revisions that required implant change. Radiographs and Harris hip score (HHS) were also evaluated. Results The mean age at primary THR was 17 (11–19) years and the mean follow-up time was 14 (3–26) years. The 10-year survival rate after primary THR (with the endpoint being any revision) was 70%. 39 patients had at least 1 revision and 16 patients had 2 or more revisions. In the latest radiographs, osteolysis and atrophy were observed in 19% and 27% of the acetabulae and 21% and 62% of the femurs, respectively. The mean HHS at the final follow-up was 83 (15–100). Interpretation The clinical score after THR in these young patients was acceptable, but many revisions had been performed. However, young patients with developmental dysplasia of the hip had lower implant survival. Moreover, the bone stock in these patients was poor, which could complicate future revisions. PMID:27435903

  18. Termite (order Blattodea, infraorder Isoptera) baiting 20 years after commercial release.

    PubMed

    Evans, Theodore A; Iqbal, Naeem

    2015-07-01

    Termite baiting is now one of the two main management tools in developed countries after 20 years of commercial release. It has two main goals: to use small amounts of active ingredient and 'colony elimination', i.e. death of all individuals in the colony. We consider how well baiting has been evaluated from 100 studies in the scientific literature. Studies have included 15 active ingredients, 23 termite species and 16 countries, yet most studies have focused on the chitin synthesis inhibitor hexaflumuron, Reticulitermes and the United States. Baiting has mostly met its goals: typically about 0.5 g of active ingredient was used, and colony elimination achieved, albeit with rates varying from 0 to 100%, and sometimes supplemented with liquid insecticide. Baiting was most successful using chitin synthesis inhibitors against Reticulitermes and Coptotermes (Rhinotermitidae), in temperate locations, although colony elimination was usually inferred indirectly - mostly by termite absence from baits - and was often slow, from 25 to 450 days. Baiting has been less tested and less successful against higher termites in tropical locations, where they are most diverse and abundant. Future research may have to consider greater termite species diversity and other active ingredients to reduce control times in order to fulfil the potential of baiting.

  19. 20 years of reprocessed Lyapunov Exponents from altimetry available on AVISO+

    NASA Astrophysics Data System (ADS)

    Pujol, Marie-Isabelle; Faugere, Yannice; D'Ovidio, Francesco; Morrow, Rosemary; Bronner, Emilie; Picot, Nicolas

    2015-04-01

    Altimetry-derived maps of Lyapunov exponents (LEs) provide proxies of (sub-)mesoscale transport fronts. They are being increasingly used in physical, biogeochemical, and ecological applications, ranging from real-time support to field studies to co-localisation of animal tracking with Lagrangian Coherent Structures. Their calculation however is more complex than standard Eulerian diagnostics, because it requires a Lagrangian algorithms which integrates the velocity field. During the past 20 years, in parallel with the altimeter measurement Level2 (a.k.a [O/I]GDR) to Level3 and Level4 (along-track cross-calibrated SLA, and multiple sensor merged maps) processing, different applications and derivated Level4+ products were developed by AVISO+. In order to better serve the users need, and in collaboration with different laboratories (LOCEAN and CTOH), the LEs and vectors are computed over the 21-year altimeter period and over the global ocean within the SSALTO/DUACS project. This product provides the position, and intensity, and orientation of fronts induced by the mesoscale eddies and underlining part of sub-mesoscale activity. We present here the Lyapunov products that will be available on AVISO+ early 2015, and some examples of applications.

  20. Life Course and Intergenerational Continuity of Intimate Partner Aggression and Physical Injury: A 20-Year Study.

    PubMed

    Knight, Kelly E; Menard, Scott; Simmons, Sara B; Bouffard, Leana A; Orsi, Rebecca

    2016-01-01

    The objective of this study is to examine continuity of intimate partner aggression (IPA), which is defined as repeated annual involvement in IPA, across respondents' life course and into the next generation, where it may emerge among adult children. A national, longitudinal, and multigenerational sample of 1,401 individuals and their adult children is analyzed. Annual data on IPA severity and physical injury were collected by the National Youth Survey Family Study across a 20-year period from 1984 to 2004. Three hypotheses and biological sex differences are tested and effect sizes are estimated. First, findings reveal evidence for life course continuity (IPA is a strong predictor of subsequent IPA), but the overall trend decreases over time. Second, intergenerational continuity is documented (parents' IPA predicts adult children's IPA), but the effect is stronger for female than for male adult children. Third, results from combined and separate, more restrictive, measures of victimization and perpetration are nearly identical except in the intergenerational analyses. Fourth, evidence for continuity is not found when assessing physical injury alone. Together, these findings imply that some but not all forms of IPA are common, continuous, and intergenerational. Life course continuity appears stronger than intergenerational continuity. PMID:27076093

  1. Clinical outcome and quality of life of patients surviving 20 years or longer after heart transplantation.

    PubMed

    Galeone, Antonella; Kirsch, Matthias; Barreda, Eleodoro; Fernandez, Flor; Vaissier, Elisabeth; Pavie, Alain; Leprince, Pascal; Varnous, Shaida

    2014-06-01

    To evaluate outcome and quality of life (QoL) in ≥ 20 years survivors after heart transplantation. Patients surviving ≥ 20 years with a single graft were retrospectively reviewed. Heterotopic, multiorgan and retransplantations were excluded. QoL was evaluated using the SF-36 survey. Eight hundred and twenty-seven heart transplants were performed from 1981 to 1993, and among these, 131 (16%) patients survived ≥ 20 years; 98 (75%) were male and mean age at transplant was 43 ± 13 years. Conditional survival in these 20 years survivors was 74.1 ± 4.3% at 23 years and 60.9 ± 5.3% at 25 years (45 deaths, 34%). Forty-four (34%) patients suffered rejection ≥ 2R. Conditional survival free from rejection ≥ 2R was 68 ± 4.1% at 5 years and 66.4 ± 4.2% at 10 years. Thirty-five (27%) patients had cardiac allograft vasculopathy (CAV) grade 2-3. Conditional CAV-free survival was 76 ± 3.8% at 20 years and 72.1 ± 4% at 25. Sixty-nine (53%) patients developed malignancy, mostly skin cancers. Conditional malignancy-free survival was 53.5 ± 4.4% at 20 years and 45.2 ± 4.6% at 25 years. At latest follow-up, 24.0 ± 3.0 years after transplantation, mean left ventricular ejection fraction was 62 ± 11% and mean physical and mental scores were 57 ± 23 and 58 ± 21, respectively. Sixteen per cent of heart recipients survived ≥ 20 years with good ventricular performance and QoL. CAV and malignancies account for late morbidity and mortality. PMID:24606025

  2. New Horizons Launch Contingency Effort

    NASA Astrophysics Data System (ADS)

    Chang, Yale; Lear, Matthew H.; McGrath, Brian E.; Heyler, Gene A.; Takashima, Naruhisa; Owings, W. Donald

    2007-01-01

    On 19 January 2006 at 2:00 PM EST, the NASA New Horizons spacecraft (SC) was launched from the Cape Canaveral Air Force Station (CCAFS), FL, onboard an Atlas V 551/Centaur/STAR™ 48B launch vehicle (LV) on a mission to explore the Pluto Charon planetary system and possibly other Kuiper Belt Objects. It carried a single Radioisotope Thermoelectric Generator (RTG). As part of the joint NASA/US Department of Energy (DOE) safety effort, contingency plans were prepared to address the unlikely events of launch accidents leading to a near-pad impact, a suborbital reentry, an orbital reentry, or a heliocentric orbit. As the implementing organization. The Johns Hopkins University Applied Physics Laboratory (JHU/APL) had expanded roles in the New Horizons launch contingency effort over those for the Cassini mission and Mars Exploration Rovers missions. The expanded tasks included participation in the Radiological Control Center (RADCC) at the Kennedy Space Center (KSC), preparation of contingency plans, coordination of space tracking assets, improved aerodynamics characterization of the RTG's 18 General Purpose Heat Source (GPHS) modules, and development of spacecraft and RTG reentry breakup analysis tools. Other JHU/APL tasks were prediction of the Earth impact footprints (ElFs) for the GPHS modules released during the atmospheric reentry (for purposes of notification and recovery), prediction of the time of SC reentry from a potential orbital decay, pre-launch dissemination of ballistic coefficients of various possible reentry configurations, and launch support of an Emergency Operations Center (EOC) on the JHU/APL campus. For the New Horizons launch, JHU/APL personnel at the RADCC and at the EOC were ready to implement any real-time launch contingency activities. A successful New Horizons launch and interplanetary injection precluded any further contingency actions. The New Horizons launch contingency was an interagency effort by several organizations. This paper

  3. Clinicopathological evaluation of renal allografts of four patients by 20-year protocol biopsies.

    PubMed

    Okamoto, Masahiko; Nobori, Shuji; Higuchi, Atsushi; Kadotani, Yayoi; Ushigome, Hidetaka; Nakamura, Kenji; Akioka, Kiyokazu; Omori, Yoshihiro; Yoshimura, Norio

    2003-01-01

    Twenty-year protocol biopsies were performed in four cases of renal transplant recipients with grafts that had survived 20 years or more. All four recipients received transplants from their parents, and never had episodes of acute rejection. They were maintained with the conventional immunosuppressive protocol including azathioprine, mizoribine, and prednisolone. Three of them had past history of malignant diseases such as breast cancer and tongue cancer. In spite of fair graft function, the microscopic findings of 20-year protocol biopsy showed various degrees of histological damage; e.g. obsolescence of the glomeruli, glomerulosclerosis, arteriole wall thickening, interstitial fibrosis and tubular atrophy. Although two of the four grafts were functioning with low serum creatinine levels (1.3-1.4 mg dL-1) at 24 years and 26 years following transplantation, respectively, the function of the other two grafts had decreased more than 20 years after transplantation. In the two grafts with decreased function, glomerulosclerosis and arteriole wall thickening tended to be more severe (Banff classification of chronic allograft nephropathy [CAN] grade II and III) at the 20-year protocol biopsy compared with the two well-functioning grafts (CAN grade I and II). We conclude that the protocol biopsies even at 20 years can contribute to predict the fate of renal allografts.

  4. Stable predictive control horizons

    NASA Astrophysics Data System (ADS)

    Estrada, Raúl; Favela, Antonio; Raimondi, Angelo; Nevado, Antonio; Requena, Ricardo; Beltrán-Carbajal, Francisco

    2012-04-01

    The stability theory of predictive and adaptive predictive control for processes of linear and stable nature is based on the hypothesis of a physically realisable driving desired trajectory (DDT). The formal theoretical verification of this hypothesis is trivial for processes with a stable inverse, but it is not for processes with an unstable inverse. The extended strategy of predictive control was developed with the purpose of overcoming methodologically this stability problem and it has delivered excellent performance and stability in its industrial applications given a suitable choice of the prediction horizon. From a theoretical point of view, the existence of a prediction horizon capable of ensuring stability for processes with an unstable inverse was proven in the literature. However, no analytical solution has been found for the determination of the prediction horizon values which guarantee stability, in spite of the theoretical and practical interest of this matter. This article presents a new method able to determine the set of prediction horizon values which ensure stability under the extended predictive control strategy formulation and a particular performance criterion for the design of the DDT generically used in many industrial applications. The practical application of this method is illustrated by means of simulation examples.

  5. High Overweight and Obesity in Fontan Patients: A 20-Year History.

    PubMed

    Chung, Stephanie T; Hong, Borah; Patterson, Lance; Petit, Christopher J; Ham, J Nina

    2016-01-01

    The prevalence of obesity in long-term survivors with complex congenital heart disease may be increasing, and little is known about the timing and onset of weight gain and growth patterns in these high-risk patients. Prevalence rates of overweight/obesity and longitudinal changes in body mass index (BMI) with age were determined in 606 patients with Fontan circulation seen at a tertiary care cardiology center from 1992 to 2012. The number of clinic encounters (n) was stratified by age group (n = 401, 2-5 years; n = 333, 6-11 years; n = 217, 12-19 years; and n = 129, >20 years). Among adults, 39% were overweight/obese at last clinic visit; 22% overweight, and 17% obese. Childhood anthropometric data were available for 82 adults, of which 15% (n = 12/82) were overweight/obese in childhood. The likelihood of being overweight/obese as an adult was three times higher if there was a BMI ≥ 85th percentile in childhood (CI 2.1-4.5, P < 0.01). Overweight/obesity in adulthood was associated with lower heart failure rates (4 vs. 19%, P = 0.03). Pediatric rates of overweight/obesity were comparable to national data (NHANES 2011-2012) in every age group: at 2-5 years, (25 vs. 23%), 6-11 years (26 vs. 34%), and 12-19 years (15 vs. 35%). Systolic blood pressure was higher in overweight/obese children as young as 2-5 years of age. Childhood and adult survivors with Fontan circulation have high rates of overweight/obesity. Childhood obesity is a strong predictor of future adiposity and is linked to changes in systolic blood pressure at a very young age.

  6. Horizon as critical phenomenon

    NASA Astrophysics Data System (ADS)

    Lee, Sung-Sik

    2016-09-01

    We show that renormalization group flow can be viewed as a gradual wave function collapse, where a quantum state associated with the action of field theory evolves toward a final state that describes an IR fixed point. The process of collapse is described by the radial evolution in the dual holographic theory. If the theory is in the same phase as the assumed IR fixed point, the initial state is smoothly projected to the final state. If in a different phase, the initial state undergoes a phase transition which in turn gives rise to a horizon in the bulk geometry. We demonstrate the connection between critical behavior and horizon in an example, by deriving the bulk metrics that emerge in various phases of the U( N ) vector model in the large N limit based on the holographic dual constructed from quantum renormalization group. The gapped phase exhibits a geometry that smoothly ends at a finite proper distance in the radial direction. The geometric distance in the radial direction measures a complexity: the depth of renormalization group transformation that is needed to project the generally entangled UV state to a direct product state in the IR. For gapless states, entanglement persistently spreads out to larger length scales, and the initial state can not be projected to the direct product state. The obstruction to smooth projection at charge neutral point manifests itself as the long throat in the anti-de Sitter space. The Poincare horizon at infinity marks the critical point which exhibits a divergent length scale in the spread of entanglement. For the gapless states with non-zero chemical potential, the bulk space becomes the Lifshitz geometry with the dynamical critical exponent two. The identification of horizon as critical point may provide an explanation for the universality of horizon. We also discuss the structure of the bulk tensor network that emerges from the quantum renormalization group.

  7. Instability of enclosed horizons

    NASA Astrophysics Data System (ADS)

    Kay, Bernard S.

    2015-03-01

    We point out that there are solutions to the scalar wave equation on dimensional Minkowski space with finite energy tails which, if they reflect off a uniformly accelerated mirror due to (say) Dirichlet boundary conditions on it, develop an infinite stress-energy tensor on the mirror's Rindler horizon. We also show that, in the presence of an image mirror in the opposite Rindler wedge, suitable compactly supported arbitrarily small initial data on a suitable initial surface will develop an arbitrarily large stress-energy scalar near where the two horizons cross. Also, while there is a regular Hartle-Hawking-Israel-like state for the quantum theory between these two mirrors, there are coherent states built on it for which there are similar singularities in the expectation value of the renormalized stress-energy tensor. We conjecture that in other situations with analogous enclosed horizons such as a (maximally extended) Schwarzschild black hole in equilibrium in a (stationary spherical) box or the (maximally extended) Schwarzschild-AdS spacetime, there will be similar stress-energy singularities and almost-singularities—leading to instability of the horizons when gravity is switched on and matter and gravity perturbations are allowed for. All this suggests it is incorrect to picture a black hole in equilibrium in a box or a Schwarzschild-AdS black hole as extending beyond the past and future horizons of a single Schwarzschild (/Schwarzschild-AdS) wedge. It would thus provide new evidence for 't Hooft's brick wall model while seeming to invalidate the picture in Maldacena's ` Eternal black holes in AdS'. It would thereby also support the validity of the author's matter-gravity entanglement hypothesis and of the paper ` Brick walls and AdS/CFT' by the author and Ortíz.

  8. Alboran jets, gyres and eddies in a 20-year high resolution simulation

    NASA Astrophysics Data System (ADS)

    Peliz, A.

    2012-04-01

    The circulation of the Alboran Sea has long been described as being in a quasi-steady state composed of the Atlantic Jet meandering on the northern bound of two conspicuous gyres: the Western Alboran Gyre and Eastern Alboran Gyre (WAG and EAG). Changes to this 2 gyre flow system (transitions or transient events) are not very well explored yet. Periodic disappearances of the WAG (collapses or migrations) have been reported, but a single event of WAG migration, observed in fall 1996, is described in detail. These studies suggested that WAG is more likely to disappear in winter after drastic changes in the inflow, and that 2-gyre steady states are essentially observed in summer. The transition periods and the occurrence of smaller eddies are episodically referred in the literature but poorly known. Using a 20 yr 2km resolution Regional Ocean Modeling System simulation of the Gulf of Cadiz-Alboran Sea basins (from the "Inter-basin Exchange in a changing Mediterranean Sea" project MedEX), a classification of the circulation types and mesoscale structures in the Alboran Sea is conducted, characterizing their duration and frequency of occurrence, and temporal evolution. The 2-gyre quasi-steady state (or blocking situation) is confirmed as the most common flow type in the Alboran (occurring during about 42% of the simulation time) and that it is more frequent in summer. However, periods of double gyre flow in winter are also present although the gyre organization is slightly different and this state is described as a 2-gyre winter type. Long stable periods of a single gyre blocking were also identified, and they occupy about 17% of the 20-year period This single gyre usually constitutes a larger version of the WAG somewhat displaced to the east and occurs all year round although it is more common in winter months. The remaining time, the Alboran Sea is in relatively fast evolving flow transitions. The transitions were classified into, WAG migrations (when the WAG clearly

  9. Spacetimes containing slowly evolving horizons

    SciTech Connect

    Kavanagh, William; Booth, Ivan

    2006-08-15

    Slowly evolving horizons are trapping horizons that are ''almost'' isolated horizons. This paper reviews their definition and discusses several spacetimes containing such structures. These include certain Vaidya and Tolman-Bondi solutions as well as (perturbatively) tidally distorted black holes. Taking into account the mass scales and orders of magnitude that arise in these calculations, we conjecture that slowly evolving horizons are the norm rather than the exception in astrophysical processes that involve stellar-scale black holes.

  10. Ecosystem development after mangrove wetland creation: plant-soil change across a 20-year chronosequence

    USGS Publications Warehouse

    Osland, Michael J.; Spivak, Amanda C.; Nestlerode, Janet A.; Lessmann, Jeannine M.; Almario, Alejandro E.; Heitmuller, Paul T.; Russell, Marc J.; Krauss, Ken W.; Alvarez, Federico; Dantin, Darrin D.; Harvey, James E.; From, Andrew S.; Cormier, Nicole; Stagg, Camille L.

    2012-01-01

    Mangrove wetland restoration and creation efforts are increasingly proposed as mechanisms to compensate for mangrove wetland losses. However, ecosystem development and functional equivalence in restored and created mangrove wetlands are poorly understood. We compared a 20-year chronosequence of created tidal wetland sites in Tampa Bay, Florida (USA) to natural reference mangrove wetlands. Across the chronosequence, our sites represent the succession from salt marsh to mangrove forest communities. Our results identify important soil and plant structural differences between the created and natural reference wetland sites; however, they also depict a positive developmental trajectory for the created wetland sites that reflects tightly coupled plant-soil development. Because upland soils and/or dredge spoils were used to create the new mangrove habitats, the soils at younger created sites and at lower depths (10-30 cm) had higher bulk densities, higher sand content, lower soil organic matter (SOM), lower total carbon (TC), and lower total nitrogen (TN) than did natural reference wetland soils. However, in the upper soil layer (0-10 cm), SOM, TC, and TN increased with created wetland site age simultaneously with mangrove forest growth. The rate of created wetland soil C accumulation was comparable to literature values for natural mangrove wetlands. Notably, the time to equivalence for the upper soil layer of created mangrove wetlands appears to be faster than for many other wetland ecosystem types. Collectively, our findings characterize the rate and trajectory of above- and below-ground changes associated with ecosystem development in created mangrove wetlands; this is valuable information for environmental managers planning to sustain existing mangrove wetlands or mitigate for mangrove wetland losses.

  11. 20 Years of persistent identifiers - Which systems are here to stay?

    NASA Astrophysics Data System (ADS)

    Klump, Jens; Huber, Robert; Lehnert, Kerstin

    2016-04-01

    Web-based persistent identifiers have been around for more than 20 years, a period long enough to start observing patterns of success and failure. Persistent identifiers were invented to address challenges arising from the distributed and disorganised nature of the internet, which not only allowed new technologies to emerge, it also made it difficult to maintain a persistent record of science. Persistent identifiers now allow unambiguous identification of resources on the net. The expectations were that persistent identifiers would lead to greater accessibility, transparency and reproducibility of research results. Over the past two decades a number of persistent identifier systems have been built, one of them being Digital Object Identifiers (DOI). While DOI were originally invented by the publishing industry, they quickly became an established way for the identification of research resources. At first, these resources referred to scholarly literature and related resources. Other identifier systems, some of them using DOI as an example, were developed as grass-roots efforts by the scientific community. The concept of using persistent identifiers has since been expanded to other, non-textual resources, like datasets (DOI, EPIC) and geological specimens (IGSN), and more recently to authors and contributors of scholarly works (ORCID), and to software and instruments. A common witticism states that "a great thing about standards is that there are so many to choose from." Setting up identifier systems is technically trivial. The real challenge lies in creating a governance system for the respective identifiers. Which systems will stand the test of time? Drawing on data from the Registry of Research Data Repositories (re3data.org) and our own experience in the field, this presentation looks at the history and adoption of existing identifier systems and how this gives us some indications towards factors influencing sustainability of these systems.

  12. Tracking 20 Years of Compound-to-Target Output from Literature and Patents

    PubMed Central

    Southan, Christopher; Varkonyi, Peter; Boppana, Kiran; Jagarlapudi, Sarma A.R.P.; Muresan, Sorel

    2013-01-01

    The statistics of drug development output and declining yield of approved medicines has been the subject of many recent reviews. However, assessing research productivity that feeds development is more difficult. Here we utilise an extensive database of structure-activity relationships extracted from papers and patents. We have used this database to analyse published compounds cumulatively linked to nearly 4000 protein target identifiers from multiple species over the last 20 years. The compound output increases up to 2005 followed by a decline that parallels a fall in pharmaceutical patenting. Counts of protein targets have plateaued but not fallen. We extended these results by exploring compounds and targets for one large pharmaceutical company. In addition, we examined collective time course data for six individual protease targets, including average molecular weight of the compounds. We also tracked the PubMed profile of these targets to detect signals related to changes in compound output. Our results show that research compound output had decreased 35% by 2012. The major causative factor is likely to be a contraction in the global research base due to mergers and acquisitions across the pharmaceutical industry. However, this does not rule out an increasing stringency of compound quality filtration and/or patenting cost control. The number of proteins mapped to compounds on a yearly basis shows less decline, indicating the cumulative published target capacity of global research is being sustained in the region of 300 proteins for large companies. The tracking of six individual targets shows uniquely detailed patterns not discernible from cumulative snapshots. These are interpretable in terms of events related to validation and de-risking of targets that produce detectable follow-on surges in patenting. Further analysis of the type we present here can provide unique insights into the process of drug discovery based on the data it actually generates. PMID

  13. Musk fragrances, DEHP and heavy metals in a 20 years old sludge treatment reed bed system.

    PubMed

    Matamoros, Víctor; Nguyen, Loc Xuan; Arias, Carlos A; Nielsen, Steen; Laugen, Maria Mølmer; Brix, Hans

    2012-08-01

    The Sludge Treatment Reed Bed (STRB) technology is a cost-efficient and environmentally friendly technology to dewater and mineralize surplus sludge from conventional wastewater treatment systems. Primary and secondary liquid sludge is loaded onto the surface of the bed over several years, where it is dewatered, mineralized and turned into a biosolid with a high dry matter content for use as an organic fertilizer on agricultural land. We analysed the concentrations of five organic micropollutants (galaxolide, tonalide, cashmeran, celestolide and DEHP) and six heavy metals (Pb, Ni, Cu, Cd, Zn and Cr) in the accumulated sludge in a 20-year old STRB in Denmark in order to assess the degradation and fate of these contaminants in a STRB and the relation to sludge composition. The results showed that the deposited sludge was dewatered to reach a dry matter content of 29%, and that up to a third of the organic content of the sludge was mineralized. The concentrations of heavy metals generally increased with depth in the vertical sludge profile due to the dewatering and mineralization of organic matter, but in all cases the concentrations were below the European Union legal limits for agricultural land disposal. The concentrations of fragrances and DEHP ranged from 10 to 9000 ng g(-1) dry mass. The attenuation of hydrophobic micropollutants from the top to the bottom layer of the reed bed ranged from 40 to 98%, except for tonalide which increased significantly with sludge depth, and consequently showed an unusual depth distribution of the galaxolide/tonalide ratio. This unexpected pattern may reflect changes imposed by a long storage time and/or different composition of the fresh sludge in the past. The lack of a significant decreasing DEHP concentration with sludge age might indicate that this compound is very persistent in STRBs. In conclusion the STRB was a feasible technology for sludge treatment before its land disposal.

  14. Where do patients treated for oral cancer die? A 20-year cohort study 1992-2011.

    PubMed

    Kamisetty, A; Magennis, P; Mayland, C; Jack, B; Lowe, D; Rogers, S N

    2015-12-01

    Of 1290 consecutive patients treated between 1992 and 2011 for primary squamous cell carcinoma of the oral cavity at a regional centre, 750 had died by August 2013. About half of them (n=373) died in hospital, 113 (15%) in a hospice, 180 (24%) at home, 57 (8%) in a care home, and 22 (3%) elsewhere. Cancer was the underlying cause of death in 64%, and of them, 56% were oral cancers. The place of death was strongly associated with the age at death and cancer being the underlying cause. The percentage of people who died from cancer at home or in a hospice rose over time across all age groups and, from 2010, accounted for two-thirds. In contrast, less than 1 in 5 who did not die from cancer, died at home or in a hospice, and in this there has been no discernible change over the last 20 years. The percentage of deaths from cancer in hospital and hospice ranged from 32%-38% and 20%-29%, respectively, across age groups. An increase in the number of deaths from cancer in care homes in those aged 75 years and over was mirrored by fewer at home. Most of those who did not die from cancer, died in hospital, two-thirds were under 65 years, 85% were aged 65-84, and 56% were older. This was mirrored by fewer deaths at home in those under 85 and more in care homes in those over 75. In conclusion, our findings suggest that patients' preferences not to die in hospital are being realised. However, at the end of their lives, patients and their carers need more support at home, and more research is required.

  15. Musk fragrances, DEHP and heavy metals in a 20 years old sludge treatment reed bed system.

    PubMed

    Matamoros, Víctor; Nguyen, Loc Xuan; Arias, Carlos A; Nielsen, Steen; Laugen, Maria Mølmer; Brix, Hans

    2012-08-01

    The Sludge Treatment Reed Bed (STRB) technology is a cost-efficient and environmentally friendly technology to dewater and mineralize surplus sludge from conventional wastewater treatment systems. Primary and secondary liquid sludge is loaded onto the surface of the bed over several years, where it is dewatered, mineralized and turned into a biosolid with a high dry matter content for use as an organic fertilizer on agricultural land. We analysed the concentrations of five organic micropollutants (galaxolide, tonalide, cashmeran, celestolide and DEHP) and six heavy metals (Pb, Ni, Cu, Cd, Zn and Cr) in the accumulated sludge in a 20-year old STRB in Denmark in order to assess the degradation and fate of these contaminants in a STRB and the relation to sludge composition. The results showed that the deposited sludge was dewatered to reach a dry matter content of 29%, and that up to a third of the organic content of the sludge was mineralized. The concentrations of heavy metals generally increased with depth in the vertical sludge profile due to the dewatering and mineralization of organic matter, but in all cases the concentrations were below the European Union legal limits for agricultural land disposal. The concentrations of fragrances and DEHP ranged from 10 to 9000 ng g(-1) dry mass. The attenuation of hydrophobic micropollutants from the top to the bottom layer of the reed bed ranged from 40 to 98%, except for tonalide which increased significantly with sludge depth, and consequently showed an unusual depth distribution of the galaxolide/tonalide ratio. This unexpected pattern may reflect changes imposed by a long storage time and/or different composition of the fresh sludge in the past. The lack of a significant decreasing DEHP concentration with sludge age might indicate that this compound is very persistent in STRBs. In conclusion the STRB was a feasible technology for sludge treatment before its land disposal. PMID:22608611

  16. Survival and Competitiveness of Bradyrhizobium japonicum Strains 20 Years after Introduction into Field Locations in Poland

    PubMed Central

    Narożna, Dorota; Pudełko, Krzysztof; Króliczak, Joanna; Golińska, Barbara; Sugawara, Masayuki; Mądrzak, Cezary J.

    2015-01-01

    It was previously demonstrated that there are no indigenous strains of Bradyrhizobium japonicum forming nitrogen-fixing root nodule symbioses with soybean plants in arable field soils in Poland. However, bacteria currently classified within this species are present (together with Bradyrhizobium canariense) as indigenous populations of strains specific for nodulation of legumes in the Genisteae tribe. These rhizobia, infecting legumes such as lupins, are well established in Polish soils. The studies described here were based on soybean nodulation field experiments, established at the Poznań University of Life Sciences Experiment Station in Gorzyń, Poland, and initiated in the spring of 1994. Long-term research was then conducted in order to study the relation between B. japonicum USDA 110 and USDA 123, introduced together into the same location, where no soybean rhizobia were earlier detected, and nodulation and competitive success were followed over time. Here we report the extra-long-term saprophytic survival of B. japonicum strains nodulating soybeans that were introduced as inoculants 20 years earlier and where soybeans were not grown for the next 17 years. The strains remained viable and symbiotically competent, and molecular and immunochemical methods showed that the strains were undistinguishable from the original inoculum strains USDA 110 and USDA 123. We also show that the strains had balanced numbers and their mobility in soil was low. To our knowledge, this is the first report showing the extra-long-term persistence of soybean-nodulating strains introduced into Polish soils and the first analyzing the long-term competitive relations of USDA 110 and USDA 123 after the two strains, neither of which was native, were introduced into the environment almost 2 decades ago. PMID:26048934

  17. Accelerated 20-year sunlight exposure simulation of a photochromic foldable intraocular lens in a rabbit model

    PubMed Central

    Werner, Liliana; Abdel-Aziz, Salwa; Peck, Carolee Cutler; Monson, Bryan; Espandar, Ladan; Zaugg, Brian; Stringham, Jack; Wilcox, Chris; Mamalis, Nick

    2011-01-01

    PURPOSE To assess the long-term biocompatibility and photochromic stability of a new photochromic hydrophobic acrylic intraocular lens (IOL) under extended ultraviolet (UV) light exposure. SETTING John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. DESIGN Experimental study. METHODS A Matrix Aurium photochromic IOL was implanted in right eyes and a Matrix Acrylic IOL without photochromic properties (n = 6) or a single-piece AcrySof Natural SN60AT (N = 5) IOL in left eyes of 11 New Zealand rabbits. The rabbits were exposed to a UV light source of 5 mW/cm2 for 3 hours during every 8-hour period, equivalent to 9 hours a day, and followed for up to 12 months. The photochromic changes were evaluated during slitlamp examination by shining a penlight UV source in the right eye. After the rabbits were humanely killed and the eyes enucleated, study and control IOLs were explanted and evaluated in vitro on UV exposure and studied histopathologically. RESULTS The photochromic IOL was as biocompatible as the control IOLs after 12 months under conditions simulating at least 20 years of UV exposure. In vitro evaluation confirmed the retained optical properties, with photochromic changes observed within 7 seconds of UV exposure. The rabbit eyes had clinical and histopathological changes expected in this model with a 12-month follow-up. CONCLUSIONS The new photochromic IOL turned yellow only on exposure to UV light. The photochromic changes were reversible, reproducible, and stable over time. The IOL was biocompatible with up to 12 months of accelerated UV exposure simulation. PMID:21241924

  18. Middle School Injuries: A 20-Year (1988–2008) Multisport Evaluation

    PubMed Central

    Beachy, Glenn; Rauh, Mitchell

    2014-01-01

    Context: Data on the incidence of injury in middle school sports are limited. Objective: To describe overall, practice, and game injury rate patterns in 29 middle school sports. Design: Descriptive epidemiology study. Setting: Injury data collected over a 20-year period (1988–2008) at a single school. Patients or Other Participants: Boy (n = 8078) and girl (n = 5960) athletes participating in 14 and 15 middle school sports, respectively. Main Outcome Measure(s): Injury status and athlete-exposures (AEs) were collected by certified athletic trainers. Incidence rates per 1000 AEs (injuries/AEs) were calculated for overall incidence, practices and games, injury location, injury type, and injury severity (time lost from participation). Rate ratios (RRs) and 95% confidence intervals (CIs) were used to compare injury rates for sex-matched sports. Results: Football had the highest injury rate for all injuries (16.03/1000 AEs) and for time-loss injuries (8.486/1000 AEs). In matched middle school sports, girls exhibited a higher injury rate for all injuries (7.686/1000 AEs, RR = 1.15, 95% CI = 1.1, 1.2) and time-loss injuries (2.944/1000 AEs, RR = 1.09, 95% CI = 1.0, 1.2) than boys (all injuries: 6.684/1000 AEs, time-loss injuries: 2.702/1000 AEs). Girls had a higher injury rate during practices (3.30/1000 AEs) than games (1.67/1000 AEs, RR = 1.97, 95% CI = 1.7, 2.4) for all sports. Only gymnastics (RR = 0.96, 95% CI = 0.3, 3.8) had a higher game injury rate for girls. Practice and game injury rates were nearly identical for boys in all sports (RR = 0.99, 95% CI = 0.9, 1.1). Only football (RR = 0.49, 95% CI = 0.4, 0.6) and boys' wrestling (RR = 0.50, 95% CI = 0.3, 0.8) reported higher game injury rates. Tendinitis injuries accounted for 19.1% of all middle school injuries. Conclusions: The risk for sport-related injury at the middle school level was greater during practices than games and greater for girls than boys in sex-matched sports. Conditioning programs may be

  19. The impact of lean production on musculoskeletal and psychosocial risks: an examination of sociotechnical trends over 20 years.

    PubMed

    Koukoulaki, Theoni

    2014-03-01

    This paper provides an extensive review of studies carried out in lean production environments in the last 20 years. It aims to identify the effects of lean production (negative or positive) on occupational health and related risk factors. Thirty-six studies of lean effects were accepted from the literature search and sorted by sector and type of outcome. Lean production was found to have a negative effect on health and risk factors; the most negative outcomes being found in the earliest studies in the automotive industry. However, examples of mixed and positive effects were also found in the literature. The strongest correlations of lean production with stress were found for characteristics found in Just-In-Time production that related to reduced cycle time and reduction of resources. Increased musculoskeletal risk symptoms were related to increases of work pace and lack of recovery time also found in Just-In-Time systems. An interaction model is developed to propose a pathway from lean production characteristics to musculoskeletal and psychosocial risk factors and also positive outcomes. An examination is also made of the changing focus of studies investigating the consequences of lean production over a 20-year period. Theories about the effects of lean production have evolved from a conceptualization that it is an inherently harmful management system, to a view that it can have mixed effects depending on the management style of the organization and the specific way it is implemented.

  20. Union Movement at Private Colleges Awakens after a 20-Year Slumber.

    ERIC Educational Resources Information Center

    Leatherman, Courtney

    2000-01-01

    Reviews trends in union organization at private colleges following the U.S. Supreme Court's decision 20 years ago denying bargaining rights to faculty at Yeshiva University (New York). Focuses on a recent decision by a labor official granting bargaining rights to faculty at Manhattan College (New York) and efforts by faculty organizers at Seton…

  1. Psychology Studies' Drive to Educational Reform in the Last 20 Years in China

    ERIC Educational Resources Information Center

    Zhang, Da-jun; Xu, Xing-chun

    2006-01-01

    In order to better understand the relationship between educational psychology research and educational reform, this essay reviews the development of educational psychology studies in the last 20 years in China. The study shows that: (1) Rapid development has been made in the areas of establishing discipline systems; (2) Research fields have been…

  2. Reading Recovery 20 Years down the Track: Looking Forward, Looking Back

    ERIC Educational Resources Information Center

    Reynolds, Meree; Wheldall, Kevin

    2007-01-01

    Reading Recovery is an intensive literacy programme designed for young students who have been identified as being at-risk of reading failure after 1 year of schooling. The intervention was developed and trialled in New Zealand over 20 years ago and is now implemented in a number of education systems. The focus of this article is on recent research…

  3. Digital Distribution of Academic Journals and Its Impact on Scholarly Communication: Looking Back after 20 Years

    ERIC Educational Resources Information Center

    Solomon, David J.

    2013-01-01

    It has been approximately 20 years since distributing scholarly journals digitally became feasible. This article discusses the broad implications of the transition to digital distributed scholarship from a historical perspective and focuses on the development of open access (OA) and the various models for funding OA in the context of the roles…

  4. 20 Years after "The Ontogeny of Human Memory: A Cognitive Neuroscience Perspective," Where Are We?

    ERIC Educational Resources Information Center

    Jabès, Adeline; Nelson, Charles A.

    2015-01-01

    In 1995, Nelson published a paper describing a model of memory development during the first years of life. The current article seeks to provide an update on the original work published 20 years ago. Specifically, we review our current knowledge on the relation between the emergence of explicit memory functions throughout development and the…

  5. Intraflagellar transport—the “new motility” 20 years later

    PubMed Central

    Kozminski, Keith G.

    2012-01-01

    Intraflagellar transport is the rapid, bidirectional movement of protein complexes along the length of most eukaryotic cilia and flagella. Discovery of this intracellular process in Chlamydomonas reinhardtii 20 years ago led to a rapid discovery of cellular mechanisms that underlie a large number of human ciliopathies. Described herein are the events that led to this discovery. PMID:22379118

  6. College Student's Health, Drinking and Smoking Patterns: What Has Changed in 20 Years?

    ERIC Educational Resources Information Center

    Hensel, Desiree; Todd, Katherine Leigh; Engs, Ruth C.

    2014-01-01

    Problem: Institutes of higher learning are increasingly trying to address the issue of problem drinking. The purpose of this study was to determine how patterns in alcohol use and smoking by college students, as well as their illness patterns, have changed over 20 years. Methods: A cross-sectional serial survey design was used for this descriptive…

  7. Decreasing Sports Activity with Increasing Age? Findings from a 20-Year Longitudinal and Cohort Sequence Analysis

    ERIC Educational Resources Information Center

    Breuer, Christoph; Wicker, Pamela

    2009-01-01

    According to cross-sectional studies in sport science literature, decreasing sports activity with increasing age is generally assumed. In this paper, the validity of this assumption is checked by applying more effective methods of analysis, such as longitudinal and cohort sequence analyses. With the help of 20 years' worth of data records from the…

  8. Social Representations of Educability in Finland: 20 Years of Continuity and Change

    ERIC Educational Resources Information Center

    Raty, Hannu; Komulainen, Katri; Hirva, Laura

    2012-01-01

    This study set out to replicate a survey conducted 20 years ago on Finnish parents' social representations of educability. A nationwide sample of parents (N = 642) were asked to indicate their opinions on a set of statements pertaining to topical educational issues. The results indicated that educational discussion is still structured by two major…

  9. Family Discord, Parental Depression, and Psychopathology in Offspring: 20-Year Follow-up

    ERIC Educational Resources Information Center

    Pilowsky, Daniel J.; Wickramaratne, Priya; Nomura, Yoko; Weissman, Myrna M.

    2006-01-01

    Objective: To determine the independent effects of parental depression and family discord on offspring psychopathology among children at high and low risk of depression. Method: Family discord factors were assessed when subjects were approximately 17 years old, and offspring diagnoses were assessed about 20 years later. Parental and offspring…

  10. Four Themes from 20 Years of Research on Infant Perception and Cognition

    ERIC Educational Resources Information Center

    Bremner, J. Gavin

    2011-01-01

    This paper reviews progress over the past 20 years in four areas of research on infant perception and cognition. Work on perception of dynamic events has identified perceptual constraints on perception of object unity and object trajectory continuity that have led to a perceptual account of early development that supplements Nativist accounts.…

  11. The Politics of Educational Reform: The Alberta Charter School Experiment 20 Years Later

    ERIC Educational Resources Information Center

    Bosetti, Lynn; Butterfield, Phil

    2016-01-01

    In this paper we examine the public charter school movement in the Province of Alberta, Canada over the past 20 years to determine how charter school policy and regulations have limited and controlled the impact of charter schools on public education. Specifically we focus on the extent to which charter schools in Alberta fulfilled the aims and…

  12. Assessing Side Effects of Pharmacotherapy Treatment of Bipolar Disorder: A 20-Year Review of the Literature

    ERIC Educational Resources Information Center

    Matson, Johnny L.; Gonzalez, Melissa L.; Smith, Kimberly R.; Terlonge, Cindy; Thorson, Ryan T.; Dixon, Dennis R.

    2006-01-01

    A substantial literature on the effective treatment of bipolar disorder has begun to appear, particularly in the last 20 years.The majority of treatments studied have employed medications, particularly mood stabilizers, a typical antipsychotics and antidepressants. Most treatments produce side effects and medications are no exception. A review of…

  13. In Patience and Hope: A 20-Year Narrative Study of a Family, School, and Community Partnership

    ERIC Educational Resources Information Center

    Higgins, Ann; Deegan, James G.

    2009-01-01

    This case study describes a 20-year journey of educational transformation from 1985 to 2005 in a bellwether, or highly developed, instance of one school, family, and community partnership--the Kileely Community Project--situated in a large social housing project in Limerick City in the Midwestern region of the Republic of Ireland. The study is a…

  14. The Parent-Child Home Program in Western Manitoba: A 20-Year Evaluation

    ERIC Educational Resources Information Center

    Gfellner, Barbara M.; McLaren, Lorraine; Metcalfe, Arron

    2008-01-01

    This article is a 20-year evaluation of the Parent-Child Home Program (PCHP) of Child and Family Services in Western Manitoba. Following Levenstein's (1979, 1988) approach, home visitors model parent-child interchanges using books and toys to enhance children's cognitive development through appropriate parenting behaviors. The evaluation provides…

  15. Intellectual Capital: For 20 Years, American Indian College Fund Has Been Investing

    ERIC Educational Resources Information Center

    Horwedel, Dina M.

    2009-01-01

    For 20 years, the American Indian College Fund (the Fund) has been helping students to afford a higher education. In addition to providing more than 4,000 scholarships for American Indian students last year, it also provides tribal colleges with funding and programmatic support. The Fund was created in 1989 by the tribal colleges and universities…

  16. Looking Back and Ahead: 20 Years of Technologies for Language Learning

    ERIC Educational Resources Information Center

    Godwin-Jones, Robert

    2016-01-01

    Over the last 20 years Robert Godwin-Jones has written 48 columns on "Emerging Technologies"; an additional six columns have been written by guest columnists. Several topics have been re-examined in regular intervals of approximately five years, namely digital literacy (Vol. 4, Num. 2; Vol. 10, Num. 2; Vol. 14, Num. 3; Vol. 19, Num. 3)…

  17. The Development of an African-Centered School--The First 20 Years

    ERIC Educational Resources Information Center

    Squire, Michelle Suzette

    2012-01-01

    This research study is a case study of the development of an African-centered school over a 20-year period. The study describes how the kindergarten-through-eighth-grade institution was established. Interview questions focused on: 1. Establishment of an African-centered institution 2. Challenges of setting up an African-centered institution 3.…

  18. Changes and Challenges in 20 Years of Research into the Development of Executive Functions

    ERIC Educational Resources Information Center

    Hughes, Claire

    2011-01-01

    This review of 20 years of developmental research on Executive Functions (EF) offers a broad-brushstroke picture that touches on multiple issues including: (i) findings from typical and atypical groups, from infancy to adolescence; (ii) advances in assessment tools and in statistical analysis; (iii) the interplay between EF and other cognitive…

  19. Understanding Rape and Sexual Assault: 20 Years of Progress and Future Directions

    ERIC Educational Resources Information Center

    Campbell, Rebecca; Wasco, Sharon M.

    2005-01-01

    During the past 20 years, researchers have documented the widespread problem of rape in American society. Approximately one in four women are raped in their adult lifetime, which causes severe psychological distress and long-term physical health problems. The impact of sexual assault extends far beyond rape survivors as their family, friends, and…

  20. Self-Rated Activity Levels and Longevity: Evidence from a 20 Year Longitudinal Study

    ERIC Educational Resources Information Center

    Mullee, Mark A.; Coleman, Peter G.; Briggs, Roger S. J.; Stevenson, James E.; Turnbull, Joanne C.

    2008-01-01

    The study reports on factors predicting the longevity of 328 people over the age of 65 drawn from an English city and followed over 20 years. Both the reported activities score and the individual's comparative evaluation of their own level of activity independently reduced the risk of death, even when health and cognitive status were taken into…

  1. 20 Years of Autonomy and Technology: How Far Have We Come and Where to Next?

    ERIC Educational Resources Information Center

    Reinders, Hayo; White, Cynthia

    2016-01-01

    Learner autonomy has become an assumed goal of language education in many parts of the world. In the 20 years since the launch of "Language Learning & Technology," the relationship among computer-assisted language learning research and practice and autonomy has become both more complex and more promising. This article traces how the…

  2. Participation in Intellectual Disability Research: A Review of 20 Years of Studies

    ERIC Educational Resources Information Center

    Cleaver, S.; Ouellette-Kuntz, H.; Sakar, A.

    2010-01-01

    Background: Researchers have noted difficulties in attracting adequate numbers of participants with intellectual disabilities (ID) to their studies. Methods: This study was a review of participation by adults with ID in research conducted in South Eastern Ontario over a 20-year period (1987-2006). Original research studies were identified by local…

  3. MOZAIC-IAGOS program : 20 years of in-situ data in the UTLS

    NASA Astrophysics Data System (ADS)

    Thouret, Valérie; Sauvage, Bastien; Nédélec, Philippe; Petzold, Andreas; Volz-Thomas, Andreas

    2014-05-01

    -latitudes thanks to 5 aircraft based in Europe flying westbound and eastbound since 1994; Transects over the African continent thanks to daily Air Namibia flights between 2006 and 2013; South Atlantic area thanks to regular flights between Europe and South America; The Asian monsoon region thanks to regular flights between Europe and the Indian-South East Asia area sampling the UT under the influence of the Asian Monsoon Anticyclone (AMA). - Ten years of CO measurements which show an increase in concentration on moving from the Western to Eastern hemisphere. In the US, Atlantic and European sectors CO concentrations have fallen by about 2% per year. - Almost 20 years of Ozone measurements at northern mid-latitudes showing a leveling-off of the mixing ratios for the last 10-12 years over the Atlantic sector while ozone is still increasing over Asia. - Almost 20 years of relative humidity measurements showing that the upper troposphere (10 - 12 km altitude, which corresponds to the aircraft cruise level) is much wetter than reflected in the model analyses of the ECMWF (European Centre for Medium range Weather Forecast).

  4. From quiescence to unrest: 20 years of satellite geodetic measurements at Santorini volcano, Greece

    NASA Astrophysics Data System (ADS)

    Parks, Michelle M.; Moore, James D. P.; Papanikolaou, Xanthos; Biggs, Juliet; Mather, Tamsin A.; Pyle, David M.; Raptakis, Costas; Paradissis, Demitris; Hooper, Andrew; Parsons, Barry; Nomikou, Paraskevi

    2015-02-01

    Periods of unrest at caldera-forming volcanic systems characterized by increased rates of seismicity and deformation are well documented. Some can be linked to eventual eruptive activity, while others are followed by a return to quiescence. Here we use a 20 year record of interferometric synthetic aperture radar (InSAR) and GPS measurements from Santorini volcano to further our understanding of geodetic signals at a caldera-forming volcano during the periods of both quiescence and unrest, with measurements spanning a phase of quiescence and slow subsidence (1993-2010), followed by a phase of unrest (January 2011 to April 2012) with caldera-wide inflation and seismicity. Mean InSAR velocity maps from 1993-2010 indicate an average subsidence rate of ~6 mm/yr over the southern half of the intracaldera island Nea Kameni. This subsidence can be accounted for by a combination of thermal contraction of the 1866-1870 lava flows and load-induced relaxation of the substrate. For the period of unrest, we use a joint inversion technique to convert InSAR measurements from three separate satellite tracks and GPS observations from 10 continuous sites into a time series of subsurface volume change. The optimal location of the inflating source is consistent with previous studies, situated north of Nea Kameni at a depth of ~4 km. However, the time series reveals two distinct pressure pulses. The first pulse corresponds to a volume change (ΔV) within the shallow magma chamber of (11.56 ± 0.14) × 106 m3, and the second pulse has a ΔV of (9.73 ± 0.10) × 106 m3. The relationship between the timing of these pulses and microseismicity observations suggests that these pulses may be driven by two separate batches of magma supplied to a shallow reservoir. We find no evidence suggesting a change in source location between the two pulses. The decline in the rates of volume change at the end of both pulses and the observed lag of the deformation signal behind cumulative seismicity

  5. Smooth horizons and quantum ripples

    NASA Astrophysics Data System (ADS)

    Golovnev, Alexey

    2015-05-01

    Black holes are unique objects which allow for meaningful theoretical studies of strong gravity and even quantum gravity effects. An infalling and a distant observer would have very different views on the structure of the world. However, a careful analysis has shown that it entails no genuine contradictions for physics, and the paradigm of observer complementarity has been coined. Recently this picture was put into doubt. In particular, it was argued that in old black holes a firewall must form in order to protect the basic principles of quantum mechanics. This AMPS paradox has already been discussed in a vast number of papers with different attitudes and conclusions. Here we want to argue that a possible source of confusion is the neglect of quantum gravity effects. Contrary to widespread perception, it does not necessarily mean that effective field theory is inapplicable in rather smooth neighbourhoods of large black hole horizons. The real offender might be an attempt to consistently use it over the huge distances from the near-horizon zone of old black holes to the early radiation. We give simple estimates to support this viewpoint and show how the Page time and (somewhat more speculative) scrambling time do appear.

  6. Distributed Fusion Receding Horizon Filtering in Linear Stochastic Systems

    NASA Astrophysics Data System (ADS)

    Song, IlYoung; Kim, DuYong; Kim, YongHoon; Lee, SukJae; Shin, Vladimir

    2009-12-01

    This paper presents a distributed receding horizon filtering algorithm for multisensor continuous-time linear stochastic systems. Distributed fusion with a weighted sum structure is applied to local receding horizon Kalman filters having different horizon lengths. The fusion estimate of the state of a dynamic system represents the optimal linear fusion by weighting matrices under the minimum mean square error criterion. The key contribution of this paper lies in the derivation of the differential equations for determining the error cross-covariances between the local receding horizon Kalman filters. The subsequent application of the proposed distributed filter to a linear dynamic system within a multisensor environment demonstrates its effectiveness.

  7. Elevation-dependent temperature trends in the Rocky Mountain Front Range: changes over a 56- and 20-year record.

    PubMed

    McGuire, Chris R; Nufio, César R; Bowers, M Deane; Guralnick, Robert P

    2012-01-01

    Determining the magnitude of climate change patterns across elevational gradients is essential for an improved understanding of broader climate change patterns and for predicting hydrologic and ecosystem changes. We present temperature trends from five long-term weather stations along a 2077-meter elevational transect in the Rocky Mountain Front Range of Colorado, USA. These trends were measured over two time periods: a full 56-year record (1953-2008) and a shorter 20-year (1989-2008) record representing a period of widely reported accelerating change. The rate of change of biological indicators, season length and accumulated growing-degree days, were also measured over the 56 and 20-year records. Finally, we compared how well interpolated Parameter-elevation Regression on Independent Slopes Model (PRISM) datasets match the quality controlled and weather data from each station. Our results show that warming signals were strongest at mid-elevations over both temporal scales. Over the 56-year record, most sites show warming occurring largely through increases in maximum temperatures, while the 20-year record documents warming associated with increases in maximum temperatures at lower elevations and increases in minimum temperatures at higher elevations. Recent decades have also shown a shift from warming during springtime to warming in July and November. Warming along the gradient has contributed to increases in growing-degree days, although to differing degrees, over both temporal scales. However, the length of the growing season has remained unchanged. Finally, the actual and the PRISM interpolated yearly rates rarely showed strong correlations and suggest different warming and cooling trends at most sites. Interpretation of climate trends and their seasonal biases in the Rocky Mountain Front Range are dependent on both elevation and the temporal scale of analysis. Given mismatches between interpolated data and the directly measured station data, we caution against

  8. On the Bartnik mass of apparent horizons

    NASA Astrophysics Data System (ADS)

    Mantoulidis, Christos; Schoen, Richard

    2015-10-01

    In this paper we characterize the intrinsic geometry of apparent horizons (outermost marginally outer trapped surfaces) in asymptotically flat spacetimes; that is, the Riemannian metrics on the two sphere which can arise. Furthermore we determine the minimal ADM mass of a spacetime containing such an apparent horizon. The results are conveniently formulated in terms of the quasi-local mass introduced by Bartnik (1989 Phys. Rev. Lett. 62 2346-8). The Hawking mass provides a lower bound for Bartnik’s quasilocal mass on apparent horizons by way of Penrose’s conjecture on time symmetric slices, proven in 1997 by Huisken and Ilmanen (2001 J. Differ. Geom. 59 353-437) and in full generality in 1999 by Bray (2001 J. Differ. Geom. 59 177-267). We compute Bartnik’s mass for all non-degenerate apparent horizons and show that it coincides with the Hawking mass. As a corollary we disprove a conjecture due to Gibbons in the spirit of Thorne’s hoop conjecture (Gibbons 2009 arXiv:0903.1580), and construct a new large class of examples of apparent horizons with the integral of the negative part of the Gauss curvature arbitrarily large.

  9. Evolving Hořava cosmological horizons

    NASA Astrophysics Data System (ADS)

    Fathi, Mohsen; Mohseni, Morteza

    2016-09-01

    Several sets of radially propagating null congruence generators are exploited in order to form 3-dimensional marginally trapped surfaces, referred to as black hole and cosmological apparent horizons in a Hořava universe. Based on this method, we deal with the characteristics of the 2-dimensional space-like spheres of symmetry and the peculiarities of having trapping horizons. Moreover, we apply this method in standard expanding and contracting FLRW cosmological models of a Hořava universe to investigate the conditions under which the extra parameters of the theory may lead to trapped/anti-trapped surfaces both in the future and in the past. We also include the cases of negative time, referred to as the finite past, and discuss the formation of anti-trapped surfaces inside the cosmological apparent horizons.

  10. Antimicrobial-Resistant Escherichia coli Survived in Dust Samples for More than 20 Years.

    PubMed

    Schulz, Jochen; Ruddat, Inga; Hartung, Jörg; Hamscher, Gerd; Kemper, Nicole; Ewers, Christa

    2016-01-01

    found that under particular conditions, dust from farm animal houses can be reservoirs for antimicrobial-resistant E. coli for at least 20 years. The survival strategies that allow E. coli to survive such long periods in environmental samples are not fully understood and could be an interesting research topic for future studies.

  11. Antimicrobial-Resistant Escherichia coli Survived in Dust Samples for More than 20 Years.

    PubMed

    Schulz, Jochen; Ruddat, Inga; Hartung, Jörg; Hamscher, Gerd; Kemper, Nicole; Ewers, Christa

    2016-01-01

    found that under particular conditions, dust from farm animal houses can be reservoirs for antimicrobial-resistant E. coli for at least 20 years. The survival strategies that allow E. coli to survive such long periods in environmental samples are not fully understood and could be an interesting research topic for future studies. PMID:27375587

  12. Antimicrobial-Resistant Escherichia coli Survived in Dust Samples for More than 20 Years

    PubMed Central

    Schulz, Jochen; Ruddat, Inga; Hartung, Jörg; Hamscher, Gerd; Kemper, Nicole; Ewers, Christa

    2016-01-01

    that under particular conditions, dust from farm animal houses can be reservoirs for antimicrobial-resistant E. coli for at least 20 years. The survival strategies that allow E. coli to survive such long periods in environmental samples are not fully understood and could be an interesting research topic for future studies. PMID:27375587

  13. Neurotoxicity in young adults 20 years after childhood exposure to lead: the Bunker Hill experience

    PubMed Central

    Stokes, L.; Letz, R.; Gerr, F.; Kolczak, M.; McNeill, F. E.; Chettle, D. R.; Kaye, W. E.

    1998-01-01

    OBJECTIVES: An epidemiological study of young adults was conducted to determine whether environmental exposure to lead during childhood was associated with current adverse neurobehavioural effects. METHODS: The exposed group consisted of 281 young adults who had been exposed environmentally to lead as children and the unexposed referent group consisted of 287 age and sex frequency matched subjects. Information on demographics, past and current health, and past exposures to neurotoxicants, and responses to the Swedish Q16 questionnaire were collected by interview. Standard neurobehavioural and neurophysiological tests were administered by computer or trained technicians. K x ray fluorescence was used to estimate tibial bone lead concentrations among the exposed and unexposed groups. Associations were examined between the exposed group and referents and tibial bone lead concentration and the neurobehavioural and neurophysiological outcomes of interest. RESULTS: Among the measures of peripheral nerve function, after controlling for confounders, sural sensory nerve evoked response amplitude, peroneal motor nerve compound motor action potential amplitude, vibrotactile thresholds of fingers and toes, and standing steadiness were significantly associated with exposure group. Among the neurobehavioural tests, hand-eye coordination, simple reaction time latency, trails B latency, symbol digit latency, serial digit, and learning error score were also significantly associated with exposure group after controlling for confounders. Exposed subjects had significantly more neuropsychiatric symptoms than the referents. Associations between tibial bone lead concentration and scores for vocabulary, vibrotactile thresholds of the fingers, and vibrotactile thresholds of the toes approached significance. CONCLUSIONS: Significant adverse central and peripheral neurological effects were found in a group of young adults 20 years after childhood environmental exposure to lead when compared

  14. Left lung agenesis discovered by a spontaneous pneumothorax in a 20-year-old girl

    PubMed Central

    Hentati, Abdessalem; Neifar, Chawki; Abid, Walid; M’saad, Sameh

    2016-01-01

    Lung agenesis is a rare condition which prognosis widely depends on associated malformations. Clinical presentation is so variable and diagnosis is often made in childhood. Here, we present a case of a 20-year-old girl who was admitted because of a spontaneous pneumothorax. Explorations concluded at a left lung agenesis, a hyperinflated right lung crossing the midline with a corresponding pneumothorax. There was no malformation else. This congenital condition and treatment for this rare presentation are discussed in detail. PMID:27051112

  15. Progressive paranoid psychosis in a 20-year-old with central congenital hypoventilation syndrome.

    PubMed

    Dranovsky, Alex; Needleman, Joshua P; Sylvester, Jessica; VanHeertum, Ronald; Muskin, Philip R

    2014-09-01

    A 20-year-old man with a history of congenital central hypoventilation syndrome presented with recent-onset psychosis, catatonia, and a diagnosis of schizophrenia. Psychiatric symptoms were resistant to conventional treatment. A fluorodeoxyglucose positron emission tomography scan of the brain obtained during the hospitalization revealed a hypometabolism distribution more consistent with hypoperfusion than with primary central nervous system disease. Increased mechanical ventilation was successfully used to treat the psychiatric symptoms.

  16. The Horizon Report: 2009 Australia-New Zealand Edition

    ERIC Educational Resources Information Center

    Johnson, L.; Levine, A.; Smith, R.; Smythe, T.; Stone, S.

    2009-01-01

    The New Media Consortium's Horizon Project is an ongoing research project that aims to identify and describe emerging technologies likely to have a large impact on teaching, learning, or creative inquiry within education around the globe over a five-year time period. The project's central products are the "Horizon Reports", an annual series of…

  17. New Horizons at Pluto

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Artist's concept of the New Horizons spacecraft as it approaches Pluto and its largest moon, Charon, in July 2015. The craft's miniature cameras, radio science experiment, ultraviolet and infrared spectrometers and space plasma experiments will characterize the global geology and geomorphology of Pluto and Charon, map their surface compositions and temperatures, and examine Pluto's atmosphere in detail. The spacecraft's most prominent design feature is a nearly 7-foot (2.1-meter) dish antenna, through which it will communicate with Earth from as far as 4.7 billion miles (7.5 billion kilometers) away.

  18. A Longitudinal Examination of Career Expectations and Outcomes of Academically Talented Students 10 and 20 Years Post-High School Graduation

    ERIC Educational Resources Information Center

    Perrone, Kristin M.; Tschopp, Molly K.; Snyder, Erin R.; Boo, Jenelle N.; Hyatt, Claudine

    2010-01-01

    The purpose of this study was to examine career expectations and outcomes for individuals who were identified as academically talented high school students. Data for this study were collected at two different time periods: 10 years and 20 years after participants' high school graduation. A decade after graduation from high school, participants…

  19. Entropy of isolated horizons revisited

    SciTech Connect

    Basu, Rudranil; Kaul, Romesh K.; Majumdar, Parthasarathi

    2010-07-15

    The decade-old formulation of the isolated horizon classically and within loop quantum gravity, and the extraction of the microcanonical entropy of such a horizon from this formulation, is reviewed, in view of recent renewed interest. There are two main approaches to this problem: one employs an SU(2) Chern-Simons theory describing the isolated horizon degrees of freedom, while the other uses a reduced U(1) Chern-Simons theory obtained from the SU(2) theory, with appropriate constraints imposed on the spectrum of boundary states ''living'' on the horizon. It is shown that both these ways lead to the same infinite series asymptotic in the horizon area for the microcanonical entropy of an isolated horizon. The leading area term is followed by an unambiguous correction term logarithmic in area with a coefficient -(3/2), with subleading corrections dropping off as inverse powers of the area.

  20. Interpersonal emotional behaviors and physical health: A 20-year longitudinal study of long-term married couples.

    PubMed

    Haase, Claudia M; Holley, Sarah R; Bloch, Lian; Verstaen, Alice; Levenson, Robert W

    2016-10-01

    Objectively coded interpersonal emotional behaviors that emerged during a 15-min marital conflict interaction predicted the development of physical symptoms in a 20-year longitudinal study of long-term marriages. Dyadic latent growth curve modeling showed that anger behavior predicted increases in cardiovascular symptoms and stonewalling behavior predicted increases in musculoskeletal symptoms. Both associations were found for husbands (although cross-lagged path models also showed some support for wives) and were controlled for sociodemographic characteristics (age, education) and behaviors (i.e., exercise, smoking, alcohol consumption, caffeine consumption) known to influence health. Both associations did not exist at the start of the study, but only emerged over the ensuing 20 years. There was some support for the specificity of these relationships (i.e., stonewalling behavior did not predict cardiovascular symptoms; anger behavior did not predict musculoskeletal symptoms; neither symptom was predicted by fear nor sadness behavior), with the anger-cardiovascular relationship emerging as most robust. Using cross-lagged path models to probe directionality of these associations, emotional behaviors predicted physical health symptoms over time (with some reverse associations found as well). These findings illuminate longstanding theoretical and applied issues concerning the association between interpersonal emotional behaviors and physical health and suggest opportunities for preventive interventions focused on specific emotions to help address major public health problems. (PsycINFO Database Record

  1. Transverse deformations of extreme horizons

    NASA Astrophysics Data System (ADS)

    Li, Carmen; Lucietti, James

    2016-04-01

    We consider the inverse problem of determining all extreme black hole solutions to the Einstein equations with a prescribed near-horizon geometry. We investigate this problem by considering infinitesimal deformations of the near-horizon geometry along transverse null geodesics. We show that, up to a gauge transformation, the linearised Einstein equations reduce to an elliptic PDE for the extrinsic curvature of a cross-section of the horizon. We deduce that for a given near-horizon geometry there exists a finite dimensional moduli space of infinitesimal transverse deformations. We then establish a uniqueness theorem for transverse deformations of the extreme Kerr horizon. In particular, we prove that the only smooth axisymmetric transverse deformation of the near-horizon geometry of extreme Kerr, such that cross-sections of the horizon are marginally trapped surfaces, corresponds to that of the extreme Kerr black hole. Furthermore, we determine all smooth and biaxisymmetric transverse deformations of the near-horizon geometry of the five-dimensional extreme Myers-Perry black hole with equal angular momenta. We find a three parameter family of solutions such that cross-sections of the horizon are marginally trapped, which is more general than the known black hole solutions. We discuss the possibility that they correspond to new five-dimensional vacuum black holes.

  2. Technologies on the Horizon: Teachers Respond to the Horizon Report

    ERIC Educational Resources Information Center

    Hodges, Charles B.; Prater, Alyssa H.

    2014-01-01

    The purpose of this study was to investigate teachers' beliefs regarding the integration of technologies from the 2011 K-12 edition of the "Horizon Report" into their local, public school contexts. Teachers read the "Horizon Report" and then participated in an asynchronous, threaded discussion focusing on technologies they…

  3. 20 Years Experience with using Low Cost Launch Opportunities for 20 Small Satellite Missions

    NASA Astrophysics Data System (ADS)

    Meerman, Maarten; Sweeting, Martin, , Sir

    these larger 'small satellites' are too big to be carried 'piggy-back'. The entrepreneurial efforts of leading FSU rocket &missile organisations in converting existing vehicles to meet the small satellite launch market at an appropriate cost has resulted in the FSU now holding the prime position for providing launches for the small satellite community - and with an excellent track record of successful launches. However, negotiating and completing a Launch Services Agreement (LSA) for a nano-micro-minisatellite with any launcher organisation is a complex matter and risky territory for the unwary or inexperienced who may easily fall prey to unexpected additional costs and delays. Whilst this warning should be heeded when dealing with European and US organisations, it is particularly relevant when negotiating launches from the FSU where there is a plethora of agencies and organisations offering a bewildering range of launch vehicles and options. Furthermore, the FSU has developed a very different technical and managerial philosophy towards launchers when compared with the west and this can be unnerving to 'first-time buyers'. Organisations experienced in dealing in the FSU will encounter a different but excellent service - once the launch service agreement has been thoroughly and fiercely negotiated in every detail. The inexperienced, however, have encountered frustrating delays, lost opportunities, unexpected taxes and costs for additional services or facilities not originally specified, and bewilderment at the different procedures used in the FSU. Fortunately, all this can be avoided with proper experience and the FSU is the current mainstay for launching small satellites quickly, affordably and reliably. Surrey has unique experience gathered over 20 years in handling launches for 20 small satellites, ranging from a 6kg nanosatellite, 50-100kg microsatellites, and a 325kg minisatellite, using 7 different launchers from the USA, Russia, Ukraine, and Europe. By working

  4. Exclusive Alternating Chemotherapy and Radiotherapy in Nonmetastatic Inflammatory Breast Cancer: 20 Years of Follow-Up

    SciTech Connect

    Bourgier, Celine; Pessoa, Eduardo Lima; Dunant, Ariane; Heymann, Steve; Spielmann, Marc; Uzan, Catherine; Mathieu, Marie-Christine; Arriagada, Rodrigo; Marsiglia, Hugo

    2012-02-01

    Background: Locoregional treatment of inflammatory breast cancer (IBC) is crucial because local relapses may be highly symptomatic and are commonly associated with distant metastasis. With a median follow-up of 20 years, we report here the long-term results of a monocentric clinical trial combining primary chemotherapy (CT) with a schedule of anthracycline-based CT and an alternating split-course of radiotherapy (RT Asterisk-Operator CT) without mastectomy. Methods and Materials: From September 1983 to December 1989, 124 women with nonmetastatic IBC (T4d M0) were treated with three cycles of primary AVCMF chemotherapy (anthracycline, vincristine, cyclophosphamide, methotrexate, and 5-fluorouracil) and then an alternating RT Asterisk-Operator CT schedule followed by three cycles of FAC. Hormonal therapy was systematically administered: ovarian irradiation (12 Gy in four fractions) or tamoxifen 20 mg daily. Results: Local control was achieved in 82% of patients. The 10- and 20-year local relapse rates were 26% and 33%, respectively, but only 10% of locally controlled cases were not associated with concurrent distant metastasis. The 10- and 20-year overall survival rates were 39% and 19%, respectively. Severe fibrosis occurred in 54% of patients, grade 3 brachial plexus neuropathy in 4%, grade 2 pneumonitis in 9%. Grade 1, 2 and 3 cardiac toxicity was observed in 3.8%, 3.8% and 1.2% of cases respectively. Conclusions: This combined regimen allowed good long-term local control without surgery. Survival rates were similar to those obtained with conventional regimens (primary chemotherapy, total mastectomy, and adjuvant radiotherapy). Since IBC continues to be an entity with a dismal prognosis, this approach, safely combining preoperative or postoperative radiation therapy and systemic treatments, should be reassessed when suitable targeted agents are available.

  5. Empirical correction for earth sensor horizon radiance variation

    NASA Technical Reports Server (NTRS)

    Hashmall, Joseph A.; Sedlak, Joseph; Andrews, Daniel; Luquette, Richard

    1998-01-01

    A major limitation on the use of infrared horizon sensors for attitude determination is the variability of the height of the infrared Earth horizon. This variation includes a climatological component and a stochastic component of approximately equal importance. The climatological component shows regular variation with season and latitude. Models based on historical measurements have been used to compensate for these systematic changes. The stochastic component is analogous to tropospheric weather. It can cause extreme, localized changes that for a period of days, overwhelm the climatological variation. An algorithm has been developed to compensate partially for the climatological variation of horizon height and at least to mitigate the stochastic variation. This method uses attitude and horizon sensor data from spacecraft to update a horizon height history as a function of latitude. For spacecraft that depend on horizon sensors for their attitudes (such as the Total Ozone Mapping Spectrometer-Earth Probe-TOMS-EP) a batch least squares attitude determination system is used. It is assumed that minimizing the average sensor residual throughout a full orbit of data results in attitudes that are nearly independent of local horizon height variations. The method depends on the additional assumption that the mean horizon height over all latitudes is approximately independent of season. Using these assumptions, the method yields the latitude dependent portion of local horizon height variations. This paper describes the algorithm used to generate an empirical horizon height. Ideally, an international horizon height database could be established that would rapidly merge data from various spacecraft to provide timely corrections that could be used by all.

  6. Infant feeding, growth and mortality: a 20-year study of an Australian Aboriginal community.

    PubMed

    Dugdale, A E

    1980-10-01

    The data are presented on infant mortality, growth and feeding for an Australian Aboriginal Settlement over 20 years from 1953 to 1972. During this period the infant mortality rate fell from about 280/1000 to about 40/1000 although the growth, infant feeding and health facilities remained almost the same. It is proposed, as a hypothesis worthy of further exploration, that major factors leading to improvement in infant mortality have been a changed attitude to small infants and an ability to use health services appropriately. These factors may be important in all developing communities. PMID:7453611

  7. Primary Hyperparathyroidism with Extensive Brown Tumors and Multiple Fractures in a 20-Year-Old Woman

    PubMed Central

    Choi, Ju Hee; Kim, Kyoung Jin; Lee, Ye Jin; Kim, Sun Hwa; Kim, Sin Gon; Jung, Kwang Yoon; Choi, Dong Seop

    2015-01-01

    A brown tumor is a benign fibrotic, erosive bony lesion caused by localized, rapid osteoclastic turnover, resulting from hyperparathyroidism. Although brown tumors are one of the most pathognomonic signs of primary hyperparathyroidism, they are rarely seen in clinical practice. In this report, we present a case of 20-year-old woman with recurrent fractures and bone pain. Plain digital radiographs of the affected bones revealed multiple erosive bone tumors, which were finally diagnosed as brown tumors associated with primary hyperparathyroidism due to a parathyroid adenoma. This case shows that multiple, and clinically severe form of brown tumors can even occur in young patients. PMID:26354493

  8. Resolving Lifshitz Horizons

    SciTech Connect

    Harrison, Sarah; Kachru, Shamit; Wang, Huajia; /Stanford U., ITP /Stanford U., Phys. Dept. /SLAC

    2012-04-24

    Via the AdS/CFT correspondence, ground states of field theories at finite charge density are mapped to extremal black brane solutions. Studies of simple gravity + matter systems in this context have uncovered wide new classes of extremal geometries. The Lifshitz metrics characterizing field theories with non-trivial dynamical critical exponent z {ne} 1 emerge as one common endpoint in doped holographic toy models. However, the Lifshitz horizon exhibits mildly singular behaviour - while curvature invariants are finite, there are diverging tidal forces. Here we show that in some of the simplest contexts where Lifshitz metrics emerge, Einstein-Maxwell-dilaton theories, generic corrections lead to a replacement of the Lifshitz metric, in the deep infrared, by a re-emergent AdS{sub 2} x R{sup 2} geometry. Thus, at least in these cases, the Lifshitz scaling characterizes the physics over a wide range of energy scales, but the mild singularity is cured by quantum or stringy effects.

  9. Landsat: Planning the Next 20 Years of Earth Observation and Science

    NASA Astrophysics Data System (ADS)

    Ryker, S. J.; Larsen, M. C.; Newman, T. R.

    2013-12-01

    The Landsat series of Earth-observing satellites began 41 years ago as a partnership between the U.S. Department of the Interior (DOI) and NASA. The U.S. Geological Survey (USGS), as DOI's Earth science agency, provides Landsat's ground systems and data and develops value-added science products and applications. In 2013 the Administration committed to continue the Landsat program for the long term, and directed NASA and USGS to develop a series of spaceborne systems to provide global, continuous Landsat-quality multispectral and thermal infrared measurements for at least 20 years beyond Landsat 9. The Administration also directed the USGS to develop the program's long-term science directions, with special emphasis on making Landsat data more easily used in a wide variety of disciplines and fields of practice. With Landsats 7 and 8 on orbit, the USGS provides data every eight days for any location on the Earth's land masses. Given eight-day data collection and Landsat's 41-year historical archive, researchers and decision-makers can assess phenomena occurring at weekly to decadal time scales. With this in mind, the USGS has identified a set of Landsat-based science products that will improve applications used by natural resource managers and will contribute to the international and interagency climate monitoring community's initiative to develop consistent climate data records (CDRs) and essential climate variables (ECVs). Key Landsat-derived CDRs include surface reflectance and surface temperature, and ECV products will include measures of fire disturbance, snow covered area, surface water extent, land cover, and above-ground green biomass. These interpretive products will provide an authoritative basis for regional to continental scale identification of historical change, monitoring of current conditions, and predicting future conditions. The Administration has also assigned USGS the responsibility to analyze Landsat users' needs to inform future operational

  10. The Horizon Report. 2005 Edition

    ERIC Educational Resources Information Center

    New Media Consortium, 2005

    2005-01-01

    This second edition of the New Media Consortium's (NMC) annual "Horizon Report" describes the continuing work of the Horizon Project, a research-oriented effort that seeks to identify and describe emerging technologies likely to have a large impact on teaching, learning, or creative expression within higher education. Drawing on an ongoing series…

  11. The Horizon Report. 2006 Edition

    ERIC Educational Resources Information Center

    New Media Consortium, 2006

    2006-01-01

    This third edition of the New Media Consortium's (NMC) annual "Horizon Report" describes the continuing work of the Horizon Project, a research-oriented effort that seeks to identify and describe emerging technologies likely to have a large impact on teaching, learning, or creative expression within higher education. Drawing on ongoing discussions…

  12. The Horizon Report. 2004 Edition

    ERIC Educational Resources Information Center

    New Media Consortium, 2004

    2004-01-01

    This first edition of the New Media Consortium's (NMC) annual "Horizon Report" details findings of the Horizon Project, a research-oriented effort that seeks to identify and describe emerging technologies likely to have a large impact on teaching, learning, or creative expression within higher education. Drawing on an ongoing series of interviews…

  13. Changes in orthodontic treatment modalities in the past 20 years: exploring the link between technology and scientific evidence.

    PubMed

    Bradley, T Gerard

    2013-01-01

    STATEMENT OF THE ISSUE: Is there a link between the many perceived advances in orthodontic techniques/therapy and science in the past 20 years? The purpose of this paper is to take five topics and match the perceptions with the scientific evidence. The variety of appliances and the swings in treatment philosophy have been dramatic, including the swing from extraction to non-extraction therapy, the introduction of space-age wires, appliances that grow mandibles, the introduction and extraordinary growth of Invisalign, and reduced friction brackets to reduce treatment time, all with claims by manufacturers of better results than ever before. The focus is on faster treatment, reduced visits/appointments and superior results. Most of these 'advancements' represent what has been the 'juggernaut of technology'. Five questions are posed, and an evidence-based approach is used to critically examine the literature in these selected topics.

  14. 20 years TraumaRegister DGU(®): development, aims and structure.

    PubMed

    2014-10-01

    The TraumaRegister DGU(®) organisational and technical development has undergone an evolution process, which started 20 years ago. Currently, the management of the registry is under the management of the "AUC - Academy for Trauma Surgery" (infrastructure) and the "Sektion NIS" (scientific responsibility). The aim of the registry was to establish an inter-hospital quality assessment tool with the option to use the increasing database for scientific evaluations of acute care. Year after year and most recently with the obligatory participation of certified hospitals the number of participating hospitals has grown as well as the registered cases per annum. Recently, even hospitals from other countries joined the registry too. Starting with six German hospitals and 260 cases in 1993, 20 years later more than 600 hospitals from eleven countries deliver over 30,000 trauma cases per year resulting in over 150,000 reported cases until 2013. In this article a historical perspective is presented of the evolution and current status of the TraumaRegister DGU(®).

  15. A 20-year data set of surface longwave fluxes in the Arctic

    SciTech Connect

    Jennifer Francis

    2004-06-15

    Creation of 20-year data set of surface infrared fluxes from satellite measurements. A reliable estimate of the surface downwelling longwave radiation flux (DLF) is a glaring void in available forcing data sets for models of Arctic sea ice and ocean circulation. We have developed a new method to estimate the DLF from a combination of satellite sounder retrievals and brightness temperatures from the TIROS Operational Vertical Sounder (TOVS), which has flown on NOAA polar-orbiting satellites continuously since late 1979. The overarching goal of this project was to generate a 20-year data set of surface downwelling longwave flux measurements from TOVS data over the Arctic Ocean. Daily gridded fields of DLF were produced with a spatial resolution of (100 km){sup 2} north of 60{sup o}N for 22.5 years rather than only 20. Surface measurements from the field station at Barrow, AK--part of the Atmospheric Radiation Measurement (ARM) Program --and from the Surface Heat Budget of the Arctic (SHEBA) were used to validate the satellite-derived fluxes and develop algorithm improvements for conditions that had resulted in systematic errors in early versions of the algorithm. The resulting data set has already been sent to two other investigators for incorporation into their research, and we will soon complete preparations to send the products to the National Snow and Ice Data Center and ARM data archive, where it can be disseminated to the scientific community.

  16. 20 years TraumaRegister DGU(®): development, aims and structure.

    PubMed

    2014-10-01

    The TraumaRegister DGU(®) organisational and technical development has undergone an evolution process, which started 20 years ago. Currently, the management of the registry is under the management of the "AUC - Academy for Trauma Surgery" (infrastructure) and the "Sektion NIS" (scientific responsibility). The aim of the registry was to establish an inter-hospital quality assessment tool with the option to use the increasing database for scientific evaluations of acute care. Year after year and most recently with the obligatory participation of certified hospitals the number of participating hospitals has grown as well as the registered cases per annum. Recently, even hospitals from other countries joined the registry too. Starting with six German hospitals and 260 cases in 1993, 20 years later more than 600 hospitals from eleven countries deliver over 30,000 trauma cases per year resulting in over 150,000 reported cases until 2013. In this article a historical perspective is presented of the evolution and current status of the TraumaRegister DGU(®). PMID:25284237

  17. Bibliometric analysis of global environmental assessment research in a 20-year period

    SciTech Connect

    Li, Wei Zhao, Yang

    2015-01-15

    Based on the samples of 113,468 publications on environmental assessment (EA) from the past 20 years, we used a bibliometric analysis to study the literature in terms of trends of growth, subject categories and journals, international collaboration, geographic distribution of publications, and scientific research issues. By applying thresholds to network centralities, a core group of countries can be distinguished as part of the international collaboration network. A frequently used keywords analysis found that the priority in assessment would gradually change from project environmental impact assessment (EIA) to strategic environmental assessment (SEA). Decision-theoretic approaches (i.e., environmental indicator selection, life cycle assessment, etc.), along with new technologies and methods (i.e., the geographic information system and modeling) have been widely applied in the EA research field over the past 20 years. Hot spots such as “biodiversity” and “climate change” have been emphasized in current EA research, a trend that will likely continue in the future. The h-index has been used to evaluate the research quality among countries all over the world, while the improvement of developing countries' EA systems is becoming a popular research topic. Our study reveals patterns in scientific outputs and academic collaborations and serves as an alternative and innovative way of revealing global research trends in the EA research field.

  18. Are We Under-Estimating Mercury in Soils? Experimental Acidification and Sample Collection Timing Demonstrate Variability in Estimates of Mercury in O-Horizon Soils at a Maine Site

    NASA Astrophysics Data System (ADS)

    Nelson, S. J.; Johnson, K. B.

    2009-12-01

    Sampling protocols, including sample timing, collection methods, preservation, and preparation, can strongly influence the results of any analysis. Organic soil horizons are a large pool of mercury (Hg) in most temperate, forested sites; minimizing the potential for under- or over- estimates in this medium is critical for discerning the fate and transport of Hg. Detailed guidance is available for ultra-clean and semi-clean handling for Hg sampling in surface waters. However, neither guidance regarding the proper time of year to sample soils nor methodological studies regarding post-sampling preservation and handling were available in the scientific literature for soil Hg sampling. Here we report on pilot work that (1) provides data for Hg in soils (O-horizon) through an entire year, to determine whether seasonality affects Hg estimates; and (2) documents the effect of treating a soil with acidic water prior to preparation and analysis. We collected O-horizon soil samples monthly from a single plot during 2008, and analyzed them for total Hg. Each month, samples were split; half were ‘control’ samples (dried then analyzed) and half were ‘acidified’ (treated with acidic (pH 2.0) ultrapure water prior to drying and analysis). We observed: (1) a three-fold range of Hg values (148-446 ppb) for the control samples (all collected within the same 2-m2 plot), varying across the twelve months in 2008 during which samples were collected; (2) differences of ~15-20% between acidified and control samples; and, (3) an apparent loss of ~100 ppb of Hg (~22%) if acidification of the dry sample was delayed a day or more. Soils collected when the antecedent period had been wet lost Hg when soils were treated with pH 2.0 solution, potentially because soluble Hg in solution could have been leached during acid treatment. This finding may help to explain why researchers have seen large pulses of Hg in streamwater flux during snowmelt. Further, our results may help to inform

  19. Falling through the black hole horizon

    NASA Astrophysics Data System (ADS)

    Brustein, Ram; Medved, A. J. M.

    2015-06-01

    We consider the fate of a small classical object, a "stick", as it falls through the horizon of a large black hole (BH). Classically, the equivalence principle dictates that the stick is affected by small tidal forces, and Hawking's quantum-mechanical model of BH evaporation makes essentially the same prediction. If, on the other hand, the BH horizon is surrounded by a "firewall", the stick will be consumed as it falls through. We have recently extended Hawking's model by taking into account the quantum fluctuations of the geometry and the classical back-reaction of the emitted particles. Here, we calculate the train exerted on the falling stick for our model. The strain depends on the near-horizon state of the Hawking pairs. We find that, after the Page time when the state of the pairs deviates significantly from maximal entanglement (as required by unitarity), the induced strain in our semiclassical model is still parametrically small. This is because the number of the disentangled pairs is parametrically smaller than the BH entropy. A firewall does, however, appear if the number of disentangled pairs near the horizon is of order of the BH entropy, as implicitly assumed in previous discussions in the literature.

  20. On the differentiability order of horizons

    NASA Astrophysics Data System (ADS)

    Szeghy, D.

    2016-06-01

    Let M be a time oriented Lorentzian manifold and H\\subset M a horizon. We will show that the differentiability order of the horizon can change only once along a generator, i.e. the following holds. If γ :I\\to H is a generator, thus, an inextendable past directed light-like geodesic on the horizon, where I=(α ,β ) or [α ,β ), then there exists a unique parameter {t}0\\in [α ,β ] and a positive integer k≥slant 1 such that the following is true. The horizon H is exactly of class {C}k at γ (t), for every t\\in ({t}0,β ), moreover H is only differentiable, but not of class {C}1 at every point γ (t), for which t\\in (α ,{t}0]. Moreover, if γ (α ) is the endpoint of only one generator then for a suitable space-like submanifold R\\subset H the first cut point of R along γ is γ (α ). Furthermore, all the points γ (t), for which t\\in [α ,{t}0], are non-injectivity points of R along γ . Moreover, if H is smooth at an interior point of γ, then H is smooth at every point of γ. MSC 53C50

  1. What happens to Petrov classification, on horizons of axisymmetric dirty black holes

    SciTech Connect

    Tanatarov, I. V.; Zaslavskii, O. B.

    2014-02-15

    We consider axisymmetric stationary dirty black holes with regular non-extremal or extremal horizons, and compute their on-horizon Petrov types. The Petrov type (PT) in the frame of the observer crossing the horizon can be different from that formally obtained in the usual (but singular in the horizon limit) frame of an observer on a circular orbit. We call this entity the boosted Petrov type (BPT), as the corresponding frame is obtained by a singular boost from the regular one. The PT off-horizon can be more general than PT on-horizon and that can be more general than the BPT on horizon. This is valid for all regular metrics, irrespective of the extremality of the horizon. We analyze and classify the possible relations between the three characteristics and discuss the nature and features of the underlying singular boost. The three Petrov types can be the same only for space-times of PT D and O off-horizon. The mutual alignment of principal null directions and the generator in the vicinity of the horizon is studied in detail. As an example, we also analyze a special class of metrics with utra-extremal horizons (for which the regularity conditions look different from the general case) and compare their off-horizon and on-horizon algebraic structure in both frames.

  2. A Report to the People. 20 Years of Your National Commitment to Public Broadcasting, 1967-1987. 1986 Annual Report.

    ERIC Educational Resources Information Center

    Corporation for Public Broadcasting, Washington, DC.

    This annual report for the Corporation for Public Broadcasting (CPB) for fiscal year 1986 also summarizes the CPB's activities over the last 20 years. The front inside cover folds out to three pages and provides a chronology of the important events in CPB history from its inception in 1967 to 1987. A narrative report on the CPB's 20 years of…

  3. Maintaining a High Physical Activity Level Over 20 Years and Weight Gain

    PubMed Central

    Hankinson, Arlene L.; Daviglus, Martha L.; Bouchard, Claude; Carnethon, Mercedes; Lewis, Cora E.; Schreiner, Pamela J.; Liu, Kiang; Sidney, Stephen

    2013-01-01

    Context Data supporting physical activity guidelines to prevent long-term weight gain are sparse, particularly during the period when the highest risk of weight gain occurs. Objective To evaluate the relationship between habitual activity levels and changes in body mass index (BMI) and waist circumference over 20 years. Design, Setting, and Participants The Coronary Artery Risk Development in Young Adults (CARDIA) study is a prospective longitudinal study with 20 years of follow-up, 1985-86 to 2005-06. Habitual activity was defined as maintaining high, moderate, and low activity levels based on sex-specific tertiles of activity scores at baseline. Participants comprised a population-based multi-center cohort (Chicago, Illinois; Birmingham, Alabama; Minneapolis, Minnesota; and Oakland, California) of 3554 men and women aged 18 to 30 years at baseline. Main Outcome Measures Average annual changes in BMI and waist circumference Results Over 20 years, maintaining high levels of activity was associated with smaller gains in BMI and waist circumference compared with low activity levels after adjustment for race, baseline BMI, age, education, cigarette smoking status, alcohol use, and energy intake. Men maintaining high activity gained 2.6 fewer kilograms (+ 0.15 BMI units per year; 95 % confidence interval [CI] 0.11-0.18 vs +0.20 in the lower activity group; 95% CI, 0.17-0.23) and women maintaining higher activity gained 6.1 fewer kilograms (+0.17 BMI units per year; 95 % CI, 0.12-0.21 vs. +0.30 in the lower activity group; 95 % CI, 0.25-0.34). Men maintaining high activity gained 3.1 fewer centimeters in waist circumference (+0.52 cm per year; 95 % CI, 0.43-0.61 cm vs 0.67 cm in the lower activity group; 95 % CI, 0.60-0.75) and women maintaining higher activity gained 3.8 fewer centimeters (+0.49 cm per year; 95 % CI, 0.39-0.58 vs 0.67 cm in the lower activity group; 95 % CI, 0.60-0.75). Conclusion Maintaining high activity levels through young adulthood may lessen

  4. The changes of subtypes in pediatric diabetes and their clinical and laboratory characteristics over the last 20 years

    PubMed Central

    Kwon, Eun Byul; Lee, Hae Sang; Shim, Young Seok; Jeong, Hwal Rim

    2016-01-01

    Purpose We studied the changes in subtypes of diabetes mellitus (DM) in children and evaluated the characteristics of each group over the past 20 years. In addition, we also examined the correlation between the glycated hemoglobin (HbA1c) values at the time of diagnosis and lipid profiles. Methods The patients were divided into 2 groups: there were a total of 190 patients under 20 years of age firstly diagnosed with DM in Ajou University Hospital. The patients in groups I and II were diagnosed from September 1995 to December 2004 and from January 2005 to April 2014, respectively. Results The characteristics were compared between the 2 groups of patients. The result showed an increase in percentage of type 2 diabetes and maturity onset diabetes of the young (MODY) patients between the 2 groups. HbA1c and total cholesterol level had statistical significances to explain increasing the low-density lipoprotein cholesterol level among age, HbA1c, total cholesterol level, and z-scores of weight and body mass index (BMI) in type 2 diabetes. R-square was 0.074. However, z-score of BMI and total cholesterol level, not HbA1c, had statistical significances in type 1 diabetic patients. R-square was 0.323. Conclusion The increase in the proportions of both type 2 diabetes and MODY in the last 10 years needed to be reminded when diagnosing the subtypes of DM, and the dyslipidemia should be attended more as a common problem of pediatric diabetic patients. PMID:27462584

  5. The microbiologic profile of diabetic foot infections in Turkey: a 20-year systematic review: diabetic foot infections in Turkey.

    PubMed

    Hatipoglu, M; Mutluoglu, M; Uzun, G; Karabacak, E; Turhan, V; Lipsky, B A

    2014-06-01

    The causative pathogens in diabetic foot infections differ in studies of European compared with Asian populations. The purpose of this study was to determine the causative microorganisms and their antibiotic sensitivity patterns in diabetic patients with a foot infection in Turkey, a country at the crossroads of these two continents. We performed a comprehensive literature search to identify all published studies pertaining to DFIs in patients cared for in Turkey. To assess changes in causative organisms and their antibiotic sensitivity patterns over time, we compared the results of just the most recent 5 years (2007-2011) with those of the past 20-years (1989-2011). We identified 31 studies meeting our inclusion criteria. Overall, these studies reported 2,097 patients, from whom 1,974 microorganisms were isolated. The total percentage of gram-negative and gram-positive aerobic bacteria were similar in each of the assessed periods. The rate of isolation of Staphylococcus aureus during the entire period, compared with just the past 5 years, was 23.8% and 19.1%, respectively, while the rate of methicillin-resistant S. aureus was 7.8% and 5.7%, respectively. The isolation rate of Pseudomonas aeruginosa was 13.7% for the entire period and 14.9% for the past 5 years. While linezolid, vancomycin and teicoplanin were the most active agents against gram-positive microorganisms, imipenem and cefoperazone-sulbactam were the most active against gram-negative microorganisms. This systematic review demonstrated few substantial changes in diabetic foot microbiology over the past 20 years. The data may help develop and update local clinical guidelines regarding antibiotic therapy for diabetic foot infections in Turkey. Further studies, especially with optimal culture methods, would be useful to validate these findings.

  6. Apparent horizons in binary black hole spacetimes

    NASA Astrophysics Data System (ADS)

    Shoemaker, Deirdre Marie

    Over the last decade, advances in computing technology and numerical techniques have lead to the possible theoretical prediction of astrophysically relevant waveforms in numerical simulations. With the building of gravitational wave detectors such as the Laser Interferometric Gravitational-Wave Observatory, we stand at the epoch that will usher in the first experimental study of strong field general relativity. One candidate source for ground based detection of gravitational waveforms, the orbit and merger of two black holes, is of great interest to the relativity community. The binary black hole problem is the two-body problem in general relativity. It is a stringent dynamical test of the theory. The problem involves the evolution of the Einstein equation, a complex system of non-linear, dynamic, elliptic-hyperbolic equations intractable in closed form. Numerical relativists are now developing the technology to evolve the Einstein equation using numerical simulations. The generation of these numerical I codes is a ``theoretical laboratory'' designed to study strong field phenomena in general relativity. This dissertation reports the successful development and application of the first multiple apparent horizon tracker applied to the generic binary black hole problem. I have developed a method that combines a level set of surfaces with a curvature flow method. This method, which I call the level flow method, locates the surfaces of any apparent horizons in the spacetime. The surface location then is used to remove the singularities from the computational domain in the evolution code. I establish the following set of criteria desired in an apparent horizon tracker: (1)The robustness of the tracker due to its lack of dependence on small changes to the initial guess; (2)The generality of the tracker in its applicability to generic spacetimes including multiple back hole spacetimes; and (3)The efficiency of the tracker algorithm in CPU time. I demonstrate the apparent

  7. Social Pharmacology: Expanding horizons

    PubMed Central

    Maiti, Rituparna; Alloza, José Luis

    2014-01-01

    In the current modern and global society, social changes are in constant evolution due to scientific progress (technology, culture, customs, and hygiene) and produce the freedom in individuals to take decisions by themselves or with their doctors toward drug consumption. In the arena of marketed drug products which includes society, individual, administration, and pharmaceutical industry, the young discipline emerged is social pharmacology or sociopharmacology. This science arises from clinical pharmacology, and deals with different parameters, which are important in creating knowledge on marketed drugs. However, the scope of “social pharmacology” is not covered by the so-called “Phase IV” alone, but it is the science that handles the postmarketing knowledge of drugs. The social pharmacology studies the “life cycle” of any marketed pharmaceutical product in the social terrain, and evaluates the effects of the real environment under circumstances totally different in the drug development process. Therefore, there are far-reaching horizons, plural, and shared predictions among health professionals and other, for beneficial use of a drug, toward maximizing the benefits of therapy, while minimizing negative social consequences. PMID:24987168

  8. Role of 3-D ultrasound in clinical obstetric practice: evolution over 20 years.

    PubMed

    Tonni, Gabriele; Martins, Wellington P; Guimarães Filho, Hélio; Araujo Júnior, Edward

    2015-05-01

    The use of 3-D ultrasound in obstetrics has undergone dramatic development over the past 20 years. Since the first publications on this application in clinical practice, several 3-D ultrasound techniques and rendering modes have been proposed and applied to the study of fetal brain, face and cardiac anatomy. In addition, 3-D ultrasound has improved calculations of the volume of fetal organs and limbs and estimations of fetal birth weight. And furthermore, angiographic patterns of fetal organs and the placenta have been assessed using 3-D power Doppler ultrasound quantification. In this review, we aim to summarize current evidence on the clinical relevance of these methodologies and their application in obstetric practice.

  9. [Meeting Report: 20 years after the First International Symposium on hepatitis C virus and related viruses].

    PubMed

    Carnero, Elena; Díez, Juana; Fortes, Purificación; Gastaminza, Pablo; Majano, Pedro; Martínez, Miguel Angel; Pérez-del-Pulgar, Sofía; Quer, Josep; López-Labrador, F Xavier

    2013-12-01

    The hepatitis C virus (HCV) was discovered by the team of Michael Houghton at Chiron Corporation in 1989 and the first symposium on HCV and related viruses was held in Venice, Italy, shortly after, in 1992. This conference was organized to advance knowledge on what then was a mysterious virus responsible for most cases of «non-A, non-B» hepatitis. During the 20 years since the first conference, the scientific quality of presentations has steadily increased, together with the tremendous advances in basic and clinical research and epidemiology. What started as a small conference on a new virus, about which there were very few data, has today become a first-in-class congress: a meeting place for basic researchers, clinicians, epidemiologists, public health experts, and industry members to present the most important advances and their application to HCV treatment and control. The nineteenth HCV symposium was held in September 2012, once again in Venice.

  10. How do animal territories form and change? Lessons from 20 years of mechanistic modelling.

    PubMed

    Potts, Jonathan R; Lewis, Mark A

    2014-06-01

    Territory formation is ubiquitous throughout the animal kingdom. At the individual level, various behaviours attempt to exclude conspecifics from regions of space. At the population level, animals often segregate into distinct territorial areas. Consequently, it should be possible to derive territorial patterns from the underlying behavioural processes of animal movements and interactions. Such derivations are an important element in the development of an ecological theory that can predict the effects of changing conditions on territorial populations. Here, we review the approaches developed over the past 20 years or so, which go under the umbrella of 'mechanistic territorial models'. We detail the two main strands to this research: partial differential equations and individual-based approaches, showing what each has offered to our understanding of territoriality and how they can be unified. We explain how they are related to other approaches to studying territories and home ranges, and point towards possible future directions. PMID:24741017

  11. Maintenance of recovery from schizophrenia at 20-year follow-up: what happened?

    PubMed

    Torgalsbøen, Anne-Kari; Rund, Bjørn Rishovd

    2010-01-01

    The present study reports longitudinal data on individuals who 20-years ago were fully recovered from previously diagnosed schizophrenia. Four subjects from the original sample consented and were interviewed at the present follow-up; data on two more subjects were secured elsewhere. A semistructured interview, the Positive and Negative Symptom Scale (PANSS) and Connor and Davidsons Resilience Scale (CD-RISC) were used to examine the psychosocial functioning and resilience of the subjects in the follow-up period. Out of the six subjects with a confirmed diagnosis of schizophrenia, two subjects were still fully recovered, one was recovered, one was in remission, one had a deteriorating course of illness, and one was deceased. The results indicate that full recovery was maintained for nearly half of the reexamined subjects when a criterion-based definition of full recovery is used. Good personality and attitudinal approaches (resilience) seem to play a role in sustaining recovery. PMID:20235619

  12. RSIC after 20 years: a look back and a look ahead

    SciTech Connect

    Maskewitz, B.F.; Roussin, R.W.; Trubev, D.K.

    1983-01-01

    On the occasion of RSIC's 20th anniversary year, this review includes highlights and lessons learned. In June 1963, the first RSIC Newsletter was published, and information analyses procedures and practices were initiated. Evidence indicates that RSIC served for 20 years as the focal point for the exchange and transfer of radiation transport technology and contributed to the advancement of the state of the art. The original concept is found to be sound: operate an information analysis center by collecting, organizing, evaluating, and analyzing all relevant information and making the information available in a form readily useful to scientists and engineers. Computing technology, a computer-based literature information system, and an advisory service remain important elements of the center. Continuing interaction between the center, developers, and users of information products and services has been a key to RSIC success. A look to the future reflects optimism.

  13. From the First Stars and Galaxies to the Epoch of Reionization: 20 Years of Computational Progress

    NASA Astrophysics Data System (ADS)

    Norman, Michael L.

    2016-06-01

    I give a progress report on computational efforts to reconstruct the first billion years of cosmic evolution beginning with the formation of the first generation of stars and galaxies, culminating in the complete photoionization of the intergalactic medium. After 20 years of intense effort, the picture is falling into place through the development and application of complex multiphysics numerical simulations of increasing physical complexity and scale on the most powerful supercomputers. I describe the processes that govern the formation of the first generation of stars, the transition to the second generation of stars, the assembly of the first galaxies, and finally the reionization of the universe. I discuss how these simulations guide the interpretation of relevant observations of the high redshift (and local) universe, along with some observational predictions of these simulations which will be tested with the next generation observatories.

  14. [20 years of a sex education clinic. Are family planning centers still needed?].

    PubMed

    Alfsen, G C; Hokstad, S

    1992-02-28

    The Sexual Information Clinic in Oslo was founded more than 20 years ago. The clinic is the largest family planning centre in Norway, treating 4,000-6,000 patients per year. In recent years the treatment of venereal diseases has become the major component of the daily work. The authors describe the different groups of patients who visit the clinic. The meanage of the patients is 21 years. The high number of legal abortions among younger women and the rising incidence of sexually transmitted diseases prove the continued existence of a need for family planning centres. The authors discuss the situation of family planning centres in Norway in general and stress the importance of their work. They argue that all venereal diseases should be treated free of charge.

  15. How do animal territories form and change? Lessons from 20 years of mechanistic modelling

    PubMed Central

    Potts, Jonathan R.; Lewis, Mark A.

    2014-01-01

    Territory formation is ubiquitous throughout the animal kingdom. At the individual level, various behaviours attempt to exclude conspecifics from regions of space. At the population level, animals often segregate into distinct territorial areas. Consequently, it should be possible to derive territorial patterns from the underlying behavioural processes of animal movements and interactions. Such derivations are an important element in the development of an ecological theory that can predict the effects of changing conditions on territorial populations. Here, we review the approaches developed over the past 20 years or so, which go under the umbrella of ‘mechanistic territorial models’. We detail the two main strands to this research: partial differential equations and individual-based approaches, showing what each has offered to our understanding of territoriality and how they can be unified. We explain how they are related to other approaches to studying territories and home ranges, and point towards possible future directions. PMID:24741017

  16. A Developmental Perspective on Alcohol and Youths 16 to 20 Years of Age

    PubMed Central

    Brown, Sandra A.; McGue, Matthew; Maggs, Jennifer; Schulenberg, John; Hingson, Ralph; Swartzwelder, Scott; Martin, Christopher; Chung, Tammy; Tapert, Susan F.; Sher, Kenneth; Winters, Ken C.; Lowman, Cherry; Murphy, Stacia

    2009-01-01

    Late adolescence (ie, 16-20 years of age) is a period characterized by escalation of drinking and alcohol use problems for many and by the onset of an alcohol use disorder for some. This heightened period of vulnerability is a joint consequence of the continuity of risk from earlier developmental stages and the unique neurologic, cognitive, and social changes that occur in late adolescence. We review the normative neurologic, cognitive, and social changes that typically occur in late adolescence, and we discuss the evidence for the impact of these transitions on individual drinking trajectories. We also describe evidence linking alcohol abuse in late adolescence with neurologic damage and social impairments, and we discuss whether these are the bases for the association of adolescent drinking with increased risks of mental health, substance abuse, and social problems in adulthood. Finally, we discuss both the challenges and successes in the treatment and prevention of adolescent drinking problems. PMID:18381495

  17. Gastric metastasis of renal cell carcinoma 20 years after radical nephrectomy

    PubMed Central

    Akay, Ebru; Kala, Mehtap; Karaman, Hatice

    2016-01-01

    Renal cell carcinomas account for 2–3% of malignant neoplasms in adults. The lung, soft tissues and bone represent the most frequent sites of distant metastasis in renal cell carcinoma. Gastric metastasis is rare. Our case was a 72-year-old man with complaints of fatigue and loss of appetite. In history, he had unergone radical nephrectomy due to renal cell carcinoma in 1993. A polypoid lesion was observed in upper gastrointestinal endoscopy. Histopathology of gastric biopsy specimen was reported as renal cell carcinoma. In English literature, there are 50 cases diagnosed as gastric metastasis from renal cell carcinoma. To date, there are only 4 cases with extremely late gastric metastasis of renal cell carcinoma. Herein, we present a rare case which underwent radical nephrectomy due to renal cell carcinoma and found to have gastric metastasis at 20. year of his follow-up. PMID:27274897

  18. 20 Years Experience with using Low Cost Launch Opportunities for 20 Small Satellite Missions

    NASA Astrophysics Data System (ADS)

    Meerman, Maarten; Sweeting, Martin, , Sir

    these larger 'small satellites' are too big to be carried 'piggy-back'. The entrepreneurial efforts of leading FSU rocket &missile organisations in converting existing vehicles to meet the small satellite launch market at an appropriate cost has resulted in the FSU now holding the prime position for providing launches for the small satellite community - and with an excellent track record of successful launches. However, negotiating and completing a Launch Services Agreement (LSA) for a nano-micro-minisatellite with any launcher organisation is a complex matter and risky territory for the unwary or inexperienced who may easily fall prey to unexpected additional costs and delays. Whilst this warning should be heeded when dealing with European and US organisations, it is particularly relevant when negotiating launches from the FSU where there is a plethora of agencies and organisations offering a bewildering range of launch vehicles and options. Furthermore, the FSU has developed a very different technical and managerial philosophy towards launchers when compared with the west and this can be unnerving to 'first-time buyers'. Organisations experienced in dealing in the FSU will encounter a different but excellent service - once the launch service agreement has been thoroughly and fiercely negotiated in every detail. The inexperienced, however, have encountered frustrating delays, lost opportunities, unexpected taxes and costs for additional services or facilities not originally specified, and bewilderment at the different procedures used in the FSU. Fortunately, all this can be avoided with proper experience and the FSU is the current mainstay for launching small satellites quickly, affordably and reliably. Surrey has unique experience gathered over 20 years in handling launches for 20 small satellites, ranging from a 6kg nanosatellite, 50-100kg microsatellites, and a 325kg minisatellite, using 7 different launchers from the USA, Russia, Ukraine, and Europe. By working

  19. Effects of storage conditions on forensic examinations of blood samples and bloodstains stored for 20 years.

    PubMed

    Hara, M; Nakanishi, H; Yoneyama, K; Saito, K; Takada, A

    2016-01-01

    The effects of various storage conditions on blood identification tests, DNA degradation, and short tandem repeat (STR) typing were evaluated. Bloodstains stored at room temperature, 4 °C, -20 °C, and -80 °C for 20 years; blood samples stored at -20 °C and -80 °C for 20 years; and fresh blood samples were analyzed. Leuco-malachite-green testing, anti-human hemoglobin (Hb) testing (using immunochromatography), and tests for hemoglobin-beta (HBB) mRNA were performed as blood identification tests. DNA degradation was evaluated by quantifying the ratios of 305 and 129 base pair (bp) fragments to 41 bp fragments. STR typing was performed using an AmpFlSTR® Identifiler™ Plus PCR Amplification Kit. All samples were positive in leuco-malachite-green staining and anti-human Hb assays. HBB was not detected in blood samples stored at -20 °C or -80 °C, although this marker was detected in all bloodstains. As indicated by the ratio of 129:41 bp and 305:41 bp DNA fragments, DNA from bloodstains stored at room temperature or 4 °C were significantly degraded compared to DNA from all other samples. STR typing analyses revealed that a portion of the loci was undetected in bloodstains stored at room temperature. Therefore, to prevent DNA degradation during long-term storage, it is recommended that bloodstains and blood be stored at below -20 °C. In addition, because bloodstains are more suitable for detection of blood-specific mRNAs than blood sample, it is desirable that blood is stored as bloodstain for this method.

  20. Fault kinematics in the 1989 Loma Prieta rupture area during 20 years before that event

    SciTech Connect

    Seeber, L.; Armbruster, J.G. )

    1990-08-01

    The Loma Prieta (LP) compressional bend of the San Andreas fault zone (SAF) appears to be multi-stranded and vertically segmented; thus, faults in this segment other than the one that ruptured in 1989 may: (1) be the source of prior large events associated with this portion of the SAF and (2) be highly stressed after the 1989 LP event. The fault that ruptured in 1989 was remarkably aseismic during the preceding 20 years; seismicity occurred on some of the neighboring faults of the system, but others remained aseismic. The Lake Elsman burst of seismicity within 1.6 years of the main shock is on a set of secondary faults within the foot-wall of the rupture. The shallow ({le}5 km) portion of the SAF, morphologically and structurally characterized as steep and predominantly strike-slip, and the imbricate thrust zone to the northeast were also quiescent. These upper crustal faults may partition oblique motion accomplished by LP-like ruptures in the lower crust into fault-parallel (transcurrence) and fault-normal motion (convergence), respectively. While the overall level of seismicity in the region around LP increased over the 20 years before 1989, the level of seismicity (number of events) on the creeping portion of the SAF next to the LP segment decreased. Moreover, the level of background seismicity on this and other fault segments varied dramatically, both up and down, in conjunction with major regional earthquakes on other segments. Thus, improved models for precursory patterns of seismicity should account for mechanistically more realistic changes than simple seismicity increase or decrease everywhere around an impending rupture.

  1. Cardiac Magnetic Resonance Imaging Findings in 20-year Survivors of Mediastinal Radiotherapy for Hodgkin's Disease

    SciTech Connect

    Machann, Wolfram; Beer, Meinrad; Breunig, Margret; Stoerk, Stefan; Angermann, Christiane; Seufert, Ines; Schwab, Franz; Koelbl, Oliver; Flentje, Michael; Vordermark, Dirk

    2011-03-15

    Purpose: The recognition of the true prevalence of cardiac toxicity after mediastinal radiotherapy requires very long follow-up and a precise diagnostic procedure. Cardiac magnetic resonance imaging (MRI) permits excellent quantification of cardiac function and identification of localized myocardial defects and has now been applied to a group of 20-year Hodgkin's disease survivors. Methods and materials: Of 143 patients treated with anterior mediastinal radiotherapy (cobalt-60, median prescribed dose 40 Gy) for Hodgkin's disease between 1978 and 1985, all 53 survivors were invited for cardiac MRI. Of those, 36 patients (68%) presented for MRI, and in 31 patients (58%) MRI could be performed 20-28 years (median, 24) after radiotherapy. The following sequences were acquired on a 1.5-T MRI: transversal T1-weighted TSE and T2-weighted half-fourier acquisition single-shot turbo-spin-echo sequences, a steady-state free precession (SSFP) cine sequence in the short heart axis and in the four-chamber view, SSFP perfusion sequences under rest and adenosine stress, and a SSFP inversion recovery sequence for late enhancement. The MRI findings were correlated with previously reconstructed doses to cardiac structures. Results: Clinical characteristics and reconstructed doses were not significantly different between survivors undergoing and not undergoing MRI. Pathologic findings were reduced left ventricular function (ejection fraction <55%) in 7 (23%) patients, hemodynamically relevant valvular dysfunction in 13 (42%), late myocardial enhancement in 9 (29%), and any perfusion deficit in 21 (68%). An association of regional pathologic changes and reconstructed dose to cardiac structures could not be established. Conclusions: In 20-year survivors of Hodgkin's disease, cardiac MRI detects pathologic findings in approximately 70% of patients. Cardiac MRI has a potential role in cardiac imaging of Hodgkin's disease patients after mediastinal radiotherapy.

  2. Clinical Features of Male Breast Cancer: Experiences from Seven Institutions Over 20 Years

    PubMed Central

    Hong, Ji Hyung; Ha, Kyung Sun; Jung, Yun Hwa; Won, Hye Sung; An, Ho Jung; Lee, Guk Jin; Kang, Donghoon; Park, Ji Chan; Park, Sarah; Byun, Jae Ho; Suh, Young Jin; Kim, Jeong Soo; Park, Woo Chan; Jung, Sang Seol; Park, Il Young; Chung, Su-Mi; Woo, In Sook

    2016-01-01

    Purpose Breast cancer treatment has progressed significantly over the past 20 years. However, knowledge regarding male breast cancer (MBC) is sparse because of its rarity. This study is an investigation of the clinicopathologic features, treatments, and clinical outcomes of MBC. Materials and Methods Clinical records of 59 MBC patients diagnosed during 1995-2014 from seven institutions in Korea were reviewed retrospectively. Results Over a 20-year period, MBC patients accounted for 0.98% among total breast cancer patients, and increased every 5 years. The median age of MBC patientswas 66 years (range, 24 to 87 years). Forty-three patients (73%) complained of a palpable breast mass initially. The median symptom duration was 5 months (range, 1 to 36 months). Mastectomy was performed in 96% of the patients. The most frequent histology was infiltrating ductal carcinoma (75%). Ninety-one percent of tumors (38/43) were estrogen receptor–positive, and 28% (11/40) showed epidermal growth factor receptor 2 (HER-2) overexpression. After curative surgery, 42% of patients (19/45) received adjuvant chemotherapy; 77% (27/35) received hormone therapy. Five out of ten patients with HER-2 overexpressing tumors did not receive adjuvant anti–HER-2 therapy, while two out of four patients with HER-2 overexpressing tumors received palliative trastuzumab for recurrent and metastatic disease. Letrozole was used for one patient in the palliative setting. The median overall survival durations were 7.2 years (range, 0.6 to 17.0 years) in patients with localized disease and 2.9 years (range, 0.6 to 4.3 years) in those with recurrent or metastatic disease. Conclusion Anti–HER-2 and hormonal therapy, except tamoxifen, have been underutilized in Korean MBC patients compared to female breast cancer patients. With the development of precision medicine, active treatment with targeted agents should be applied. Further investigation of the unique pathobiology of MBC is clinically warranted

  3. A History of the Environmental Management Advisory Board: 20 Years of Service and Partnership - 13219

    SciTech Connect

    Ellis, Kristen; Schmitt, Elizabeth

    2013-07-01

    The Environmental Management Advisory Board (EMAB or Board) was chartered under the Federal Advisory Committee Act (FACA) in 1992 to provide the Assistant Secretary for Environmental Management (EM) with independent and external advice, information, and recommendations on corporate issues relating to accelerated site clean-up and risk reduction throughout the EM complex. Over the course of the past 20 years, the composition and focus of the Board have varied widely to address the changing needs of the program. EMAB began as the Environmental Restoration and Waste Management Advisory Committee, formed to provide advice on an EM Programmatic Environmental Impact Statement. In 1994, the Board was restructured to function more as an executive-level, limited member advisory board whose membership provides insight of leading industry experts and the viewpoints of representatives from critical stakeholder constituencies. Throughout the 20 years of its existence, EMAB has covered a wide variety of topics and produced nearly 200 recommendations. These recommendations have resulted in several policy changes and improvements within EM. Most recently, EMAB has been credited for its contribution to the EM Energy Park Initiative, forerunner of the DOE Asset Revitalization Initiative; creation of the EM Offices of Communications and External Affairs; improvement of acquisition and project management strategies and culture; and several recommendations related to the Waste Treatment Plant and the tank waste programs at Hanford and the Savannah River Site. The wealth of experience and knowledge the Assistant Secretary can leverage through utilization of the Board continues to support fulfillment of EM's mission. In commemoration of EMAB's 20. anniversary, this paper will provide further context for the evolution of the Board, the role FACA plays in its administration, and a look at the members' current objectives and EM's expectations for the future. (authors)

  4. Temporal and Spatial Trends of Mercury Speciation in the Mediterranean Sea - 20 years of measurements

    NASA Astrophysics Data System (ADS)

    Horvat, M.; Kotnik, J.; Fajon, V.; Zivkovic, I.; Begu, E.; Pirrone, N.; Sprovieri, F.

    2015-12-01

    Despite the geological mercury anomaly in the Mediterranean Basin, the concentrations of Hg Hg and its compounds are generally lower than those found in the Atlantic and Pacific waters. Temporal and spatial trends of total mercury and its species in surface and deep waters (dissolved gaseous mercury - DGM, mono and di-methylmercuy - MMHg, and DMHg) obtained during last 20 years will be presented. Total mercury Hg levels in open waters are generally very low (0.81-2.33 pM, av. 1.46 pM) and remain constant over the years. Hg speciation data showed that DGM accounts for up to 50% while MMHg accounted to up to 15% of total Hg in water. Significant spatial and temporal differences were observed for mercury speciation. The relatively high concentrations and fractions of DGM and MMHg indicate the high reactivity of Hg in open marine waters. DGM was present in surface waters mainly as Hg0 as no DMHg was detected at the surface, while towards the bottom a noticeable, but relatively small fraction of DMHg was present. It was found that DGM species were lower in surface with an increasing trend towards the bottom, especially in the tectonically active areas, indicating its geotectonic origin. In surface waters, DGM exhibited higher values in summer. MMHg profiles are mostly related to Chl-a and oxygen concentrations. This underlines the role of planktonic production and regeneration in methylation/ demethylation processes. The low MMHg concentrations found in shelf edge or coastal sediments and water over sediment indicate that coastal or shelf sediments are not a significant MMHg source for adjacent open sea waters. Anthropogenic and natural point sources show local enrichments, while natural diffusive sources influence Hg speciation over larger areas. The results allowed estimation of temporal mass balances to be evaluated for the Mediterranean Sea. Comparability of the measured results was secured by strict quality control measures over the 20 years.

  5. Effects of storage conditions on forensic examinations of blood samples and bloodstains stored for 20 years.

    PubMed

    Hara, M; Nakanishi, H; Yoneyama, K; Saito, K; Takada, A

    2016-01-01

    The effects of various storage conditions on blood identification tests, DNA degradation, and short tandem repeat (STR) typing were evaluated. Bloodstains stored at room temperature, 4 °C, -20 °C, and -80 °C for 20 years; blood samples stored at -20 °C and -80 °C for 20 years; and fresh blood samples were analyzed. Leuco-malachite-green testing, anti-human hemoglobin (Hb) testing (using immunochromatography), and tests for hemoglobin-beta (HBB) mRNA were performed as blood identification tests. DNA degradation was evaluated by quantifying the ratios of 305 and 129 base pair (bp) fragments to 41 bp fragments. STR typing was performed using an AmpFlSTR® Identifiler™ Plus PCR Amplification Kit. All samples were positive in leuco-malachite-green staining and anti-human Hb assays. HBB was not detected in blood samples stored at -20 °C or -80 °C, although this marker was detected in all bloodstains. As indicated by the ratio of 129:41 bp and 305:41 bp DNA fragments, DNA from bloodstains stored at room temperature or 4 °C were significantly degraded compared to DNA from all other samples. STR typing analyses revealed that a portion of the loci was undetected in bloodstains stored at room temperature. Therefore, to prevent DNA degradation during long-term storage, it is recommended that bloodstains and blood be stored at below -20 °C. In addition, because bloodstains are more suitable for detection of blood-specific mRNAs than blood sample, it is desirable that blood is stored as bloodstain for this method. PMID:26832383

  6. Characteristics of dissolved organic matter following 20years of peatland restoration.

    PubMed

    Höll, Bettina S; Fiedler, Sabine; Jungkunst, Hermann F; Kalbitz, Karsten; Freibauer, Annette; Drösler, Matthias; Stahr, Karl

    2009-12-15

    The changes in the amounts and composition of dissolved organic matter (DOM) following long-term peat restoration are unknown, although this fraction of soil organic matter affects many processes in such ecosystems. We addressed this lack of knowledge by investigating a peatland in south-west Germany that was partly rewetted 20 years ago. A successfully restored site and a moderately drained site were compared, where the mean groundwater levels were close to the soil surface and around 30 cm below surface, respectively. The concentrations of dissolved organic carbon (DOC) at 4 depths were measured over one year. The specific absorbance was measured at 280 nm and the fluorescence spectra were used to describe the aromaticity and complexity of DOM. The investigations showed that 20 years of peatland restoration was able to create typical peatland conditions. The rewetted site had significantly lower DOC concentrations at different depths compared to the drained site. The specific UV absorbance showed that the rewetted site had a lower level of aromatic DOM structures. The decreasing specific UV absorbance might indicate an increasing contribution of small organic molecules to DOM. It was hypothesized that the decreasing DOC concentrations and the relative enrichment of small, readily degradable organic molecules, reflect the slower decomposition of organic matter after the re-establishment of the water table. Seasonal trends provided substantial evidence for our hypothesis that reduced DOC concentrations were caused by reduced peat decomposition. During summer, the elevated DOC values were accompanied by an increase in DOM aromaticity and complexity. Our results demonstrated a close link between C mineralization and DOC production. We concluded that long-term peatland restoration in the form of the successful re-establishment of the water table might result in reduced peat decomposition and lower DOC concentrations. The restoration of peatlands seems to have a

  7. Anterior cruciate ligament injury after more than 20 years: I. Physical activity level and knee function.

    PubMed

    Tengman, E; Brax Olofsson, L; Nilsson, K G; Tegner, Y; Lundgren, L; Häger, C K

    2014-12-01

    Little is known about physical activity level and knee function including jump capacity and fear of movement/reinjury more than 20 years after injury of the anterior cruciate ligament (ACL). Seventy persons with unilateral ACL injury participated (23 ± 2 years post-injury): 33 treated with physiotherapy in combination with surgical reconstruction (ACLR ), and 37 treated with physiotherapy alone (ACLPT ). These were compared with 33 age- and gender-matched controls. Assessment included knee-specific and general physical activity level [Tegner activity scale, International Physical Activity Questionnaire (IPAQ)], knee function [Lysholm score, Knee injury and Osteoarthritis Outcome Score (KOOS)], jump capacity (one-leg hop, vertical jump, side hops), and fear of movement/reinjury [Tampa Scale for Kinesiophobia (TSK)]. Outcomes were related to degree of osteoarthritis (OA). ACL-injured had lower Lysholm, KOOS, and Tegner scores than controls (P < 0.001), while IPAQ score was similar. ACL-injured demonstrated inferior jump capacity in injured compared with noninjured leg (6-25%, P < 0.001-P = 0.010 in the different jumps), while noninjured leg had equal jump capacity as controls. ACL groups scored 33 ± 7 and 32 ± 7 of 68 on TSK. Lower scores on Lysholm and KOOS symptom were seen for persons with moderate-to-high OA than for no-or-low OA, while there were no differences for physical activity and jump capacity. Regardless of treatment, there are still negative knee-related effects of ACL injury more than 20 years later.

  8. Quantum correlations across the black hole horizon

    SciTech Connect

    Schuetzhold, Ralf; Unruh, William G.

    2010-06-15

    Inspired by the condensed-matter analogues of black holes, we study the quantum correlations across the event horizon reflecting the entanglement between the outgoing particles of the Hawking radiation and their in-falling partners. For a perfectly covariant theory, the total correlation is conserved in time and piles up arbitrary close to the horizon in the past, where it merges into the singularity of the vacuum two-point function at the light cone. After modifying the dispersion relation (i.e., breaking Lorentz invariance) for large k, on the other hand, the light cone is smeared out and the entanglement is not conserved but actually created in a given rate per unit time.

  9. NIR Color vs Launch Date: A 20-year Analysis of Space Weathering Effects on the Boeing 376 Spacecraft

    NASA Astrophysics Data System (ADS)

    Frith, J.; Anz-Meador, P.; Lederer, S.; Cowardin, H.; Buckalew, B.

    The Boeing HS-376 spin stabilized spacecraft was a popular design that was launched continuously into geosynchronous orbit starting in 1980 with the last launch occurring in 2002. Over 50 of the HS-376 buses were produced to fulfill a variety of different communication missions for countries all over the world. The design of the bus is easily approximated as a telescoping cylinder that is covered with solar cells and an Earth facing antenna that is despun at the top of the cylinder. The similarity in design and the number of spacecraft launched over a long period of time make the HS-376 a prime target for studying the effects of solar weathering on solar panels as a function of time. A selection of primarily non-operational HS-376 spacecraft launched over a 20 year time period were observed using the United Kingdom Infrared Telescope on Mauna Kea and multi-band near-infrared photometry produced. Each spacecraft was observed for an entire night cycling through ZYJHK filters and time-varying colors produced to compare near-infrared color as a function of launch date. The resulting analysis shown here may help in the future to set launch date constraints on the parent object of unidentified debris objects or other unknown spacecraft.

  10. NIR Color vs Launch Date: A 20-Year Analysis of Space Weathering Effects on the Boeing 376 Spacecraft

    NASA Technical Reports Server (NTRS)

    Frith, James; Anz-Meador, Philip; Lederer, Sue; Cowardin, Heather; Buckalew, Brent

    2015-01-01

    The Boeing HS-376 spin stabilized spacecraft was a popular design that was launched continuously into geosynchronous orbit starting in 1980 with the last launch occurring in 2002. Over 50 of the HS-376 buses were produced to fulfill a variety of different communication missions for countries all over the world. The design of the bus is easily approximated as a telescoping cylinder that is covered with solar cells and an Earth facing antenna that is despun at the top of the cylinder. The similarity in design and the number of spacecraft launched over a long period of time make the HS-376 a prime target for studying the effects of solar weathering on solar panels as a function of time. A selection of primarily non-operational HS-376 spacecraft launched over a 20 year time period were observed using the United Kingdom Infrared Telescope on Mauna Kea and multi-band near-infrared photometry produced. Each spacecraft was observed for an entire night cycling through ZYJHK filters and time-varying colors produced to compare near-infrared color as a function of launch date. The resulting analysis shown here may help in the future to set launch date constraints on the parent object of unidentified debris objects or other unknown spacecraft.

  11. Unruh effect without Rindler horizon

    NASA Astrophysics Data System (ADS)

    Nicolaevici, Nistor

    2015-02-01

    We investigate the Unruh effect for a massless scalar field in the two-dimensional Minkowski space in the presence of a uniformly accelerated perfect mirror, with the trajectory of the mirror chosen in such a way that the mirror completely masks the Rindler horizon from the space-time region of interest. We find that the characteristic thermodynamical properties of the effect remain unchanged, i.e. the response of a uniformly co-accelerated Unruh detector and the distribution of the Rindler particles retain their thermal form. However, since in this setup there are no unobserved degrees of freedom of the field, the thermal statistics of the Rindler particles are inconsistent with an initial pure vacuum, which leads us to reconsider the problem for the more physical case when the mirror is inertial in the past. In these conditions we find that the distribution of the Rindler particles is non-thermal even in the limit of infinite acceleration times, but effective thermal statistics can be recovered provided that one is restricted to the expectation values of smeared operators associated with finite norm Rindler states. We explain how the thermal statistics in our problem can be understood in analogy with those in the conventional version of the effect.

  12. Area Theorem and Smoothness of Compact Cauchy Horizons

    NASA Astrophysics Data System (ADS)

    Minguzzi, E.

    2015-10-01

    We obtain an improved version of the area theorem for not necessarily differentiable horizons which, in conjunction with a recent result on the completeness of generators, allows us to prove that under the null energy condition every compactly generated Cauchy horizon is smooth and compact. We explore the consequences of this result for time machines, topology change, black holes and cosmic censorship. For instance, it is shown that compact Cauchy horizons cannot form in a non-empty spacetime which satisfies the stable dominant energy condition wherever there is some source content.

  13. Quantum correlations through event horizons: Fermionic versus bosonic entanglement

    SciTech Connect

    Martin-Martinez, Eduardo; Leon, Juan

    2010-03-15

    We disclose the behavior of quantum and classical correlations among all the different spatial-temporal regions of a space-time with an event horizon, comparing fermionic with bosonic fields. We show the emergence of conservation laws for entanglement and classical correlations, pointing out the crucial role that statistics plays in the information exchange (and more specifically, the entanglement tradeoff) across horizons. The results obtained here could shed new light on the problem of information behavior in noninertial frames and in the presence of horizons, giving better insight into the black-hole information paradox.

  14. Status of the JPL Horizons Ephemeris System

    NASA Astrophysics Data System (ADS)

    Giorgini, Jon D.

    2015-08-01

    Since 1996, the NASA/Jet Propulsion Laboratory on-line Horizons system has provided open access to the latest JPL orbit solutions through customizable ephemeris generation and searches. Currently, high-precision ephemerides for more than 683,000 objects are available: all known solar system bodies, several dozen spacecraft, system barycenters, and some libration points.Since inception, Horizons has produced 150 million ephemeris products in response to 70.4 million connections by 800,000 unique IP addresses. Recent usage is typically 6000 unique users requesting 4,000,000 ephemeris products per month.Horizons is freely accessible without an account and may be used and automated through any of three interfaces: interactive telnet connection, web-browser form, or by sending e-mail command-files.Asteroid and comet ephemerides are numerically integrated on request using JPL's DASTCOM5 database of initial conditions which is kept current by a separate process; as new measurements and discoveries are reported by the Minor Planet Center, they are automatically processed into new JPL orbit solutions. Radar targets and other objects of high interest have their orbit solutions manually examined and updated into the database.For asteroids and comets, SPK files may be dynamically created using Horizons. This is effectively a recording of the integrator output. The binary files may then be efficiently interpolated by user software to exactly reproduce the trajectory without having to duplicate the numerically integrated n-body dynamical model or PPN equations of motion.Other Horizons output is numerical and in the form of plain-text observer, vector, osculating element, and close-approach tables. More than one hundred quantities can be requested in various time-scales and coordinate systems. For asteroids and comets, statistical uncertainties can be mapped to output times to assess position and motion uncertainties.Horizons is consistent with the DE431 solar system solution

  15. Environmental accounting as a management tool in the Mediterranean context: the Spanish economy during the last 20 years.

    PubMed

    Lomas, Pedro L; Alvarez, Sergio; Rodríguez, Marta; Montes, Carlos

    2008-07-01

    Although human presence is one of the main characteristics of the Mediterranean identity since ancient times, a false dialectic between conservation and social-economic development has emerged in recent decades. On the one hand, an economic growth policy is taken as the paradigm of social-economic development; on the other hand, there is a multi-scale conservation policy, in which natural protected areas, as patches of preserved nature, are used as one of the main tools to deal with the challenge of sustainability. The Mediterranean Basin is the habitat of many unique species and one of the 25 main biodiversity hotspots in the world, and as a consequence a strong conservation policy has been used to protect environmental values. At the same time, Mediterranean countries are deeply involved in promoting strong economic growth policies, which are not always compatible with environmental ones. In this paper, Spain has been studied as one model of this situation. Due to political reasons, Spanish economic growth and conservationist policies were pursued together during the last 20 years. As a result, Spain owns one of the largest networks of natural protected areas in Western Europe, and at the same time it has experienced one of the strongest periods of economic growths in the European and Mediterranean context during the 1980s and 1990s. An historical series of resource use in five annual periods in the last 20 years of conservation policy, and the effects on the preservation of natural capital have been investigated by means of the eMergy (spelled with an 'm') synthesis approach, which was used to characterize the flow of environmental services supplied by ecosystems, but not in monetary terms. This study shows that Spain is becoming less self-sufficient and more inefficient in resource use, comprehensively measured in eMergy terms. A large part of Spain's economy depends on imported goods and services, and most economic activities are based on tourist services and

  16. Environmental accounting as a management tool in the Mediterranean context: the Spanish economy during the last 20 years.

    PubMed

    Lomas, Pedro L; Alvarez, Sergio; Rodríguez, Marta; Montes, Carlos

    2008-07-01

    Although human presence is one of the main characteristics of the Mediterranean identity since ancient times, a false dialectic between conservation and social-economic development has emerged in recent decades. On the one hand, an economic growth policy is taken as the paradigm of social-economic development; on the other hand, there is a multi-scale conservation policy, in which natural protected areas, as patches of preserved nature, are used as one of the main tools to deal with the challenge of sustainability. The Mediterranean Basin is the habitat of many unique species and one of the 25 main biodiversity hotspots in the world, and as a consequence a strong conservation policy has been used to protect environmental values. At the same time, Mediterranean countries are deeply involved in promoting strong economic growth policies, which are not always compatible with environmental ones. In this paper, Spain has been studied as one model of this situation. Due to political reasons, Spanish economic growth and conservationist policies were pursued together during the last 20 years. As a result, Spain owns one of the largest networks of natural protected areas in Western Europe, and at the same time it has experienced one of the strongest periods of economic growths in the European and Mediterranean context during the 1980s and 1990s. An historical series of resource use in five annual periods in the last 20 years of conservation policy, and the effects on the preservation of natural capital have been investigated by means of the eMergy (spelled with an 'm') synthesis approach, which was used to characterize the flow of environmental services supplied by ecosystems, but not in monetary terms. This study shows that Spain is becoming less self-sufficient and more inefficient in resource use, comprehensively measured in eMergy terms. A large part of Spain's economy depends on imported goods and services, and most economic activities are based on tourist services and

  17. The absence of horizon in black-hole formation

    NASA Astrophysics Data System (ADS)

    Ho, Pei-Ming

    2016-08-01

    With the back-reaction of Hawking radiation taken into consideration, the work of Kawai, Matsuo and Yokokura [1] has shown that, under a few assumptions, the collapse of matter does not lead to event horizon nor apparent horizon. In this paper, we relax their assumptions and elaborate on the space-time geometry of a generic collapsing body with spherical symmetry. The geometry outside the collapsing sphere is found to be approximated by the geometry outside the white-hole horizon, hence the collapsing matter remains outside the Schwarzschild radius. As particles in Hawking radiation are created in the vicinity of the collapsing matter, the information loss paradox is alleviated. Assuming that the collapsing body evaporates within finite time, there is no event horizon.

  18. Age and blood pressure changes. A 20-year follow-up study in nuns in a secluded order.

    PubMed

    Timio, M; Verdecchia, P; Venanzi, S; Gentili, S; Ronconi, M; Francucci, B; Montanari, M; Bichisao, E

    1988-10-01

    In a prospective study, 144 white nuns belonging to a secluded monastic order and 138 white control laywomen were followed for 20 years to investigate whether living for a long time in a stress-free environment influences the effect of aging on blood pressure. Silence, meditation, and isolation from society are the distinctive features of the life-style examined. At study entry, blood pressure was not dissimilar in the nuns and the control group, but it increased over time only in the controls, with a mean slope of the regression line (beta coefficient) of 0.089 in the nuns (NS) and 2.171 in the controls (p less than 0.0001) for systolic blood pressure and of 0.054 in the nuns (NS) and 0.742 in the controls (p less than 0.0001) for diastolic blood pressure. Weight and body mass index increased similarly over time in the two groups. Family history of hypertension was not dissimilar between the groups. Serum cholesterol and triglycerides, higher at study entry in the nuns, increased similarly over time in the two groups. Twenty-four-hour urinary sodium excretion, collected randomly in both groups, did not differ over time between nuns and controls. None of the women smoked or used oral contraceptives. Educational level was higher in the control group, but subgroups of 48 nuns and 52 laywomen of comparable educational level maintained the same difference in the blood pressure trend over time as in the main cohort. Parity affected the increase of systolic, but not of diastolic, blood pressure with age among the laywomen, but nuns and no-childbirth controls maintained a significantly different blood pressure trend over time.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Dynamical AdS strings across horizons

    DOE PAGES

    Ishii, Takaaki; Murata, Keiju

    2016-03-01

    We examine the nonlinear classical dynamics of a fundamental string in anti-deSitter spacetime. The string is dual to the flux tube between an external quark-antiquark pair in $N = 4$ super Yang-Mills theory. We perturb the string by shaking the endpoints and compute its time evolution numerically. We find that with sufficiently strong perturbations the string continues extending and plunges into the Poincare´ horizon. In the evolution, effective horizons are also dynamically created on the string worldsheet. The quark and antiquark are thus causally disconnected, and the string transitions to two straight strings. The forces acting on the endpoints vanishmore » with a power law whose slope depends on the perturbations. Lastly, the condition for this transition to occur is that energy injection exceeds the static energy between the quark-antiquark pair.« less

  20. Dynamical AdS strings across horizons

    NASA Astrophysics Data System (ADS)

    Ishii, Takaaki; Murata, Keiju

    2016-03-01

    We examine the nonlinear classical dynamics of a fundamental string in anti-de Sitter spacetime. The string is dual to the flux tube between an external quark-antiquark pair in {N}=4 super Yang-Mills theory. We perturb the string by shaking the endpoints and compute its time evolution numerically. We find that with sufficiently strong perturbations the string continues extending and plunges into the Poincaré horizon. In the evolution, effective horizons are also dynamically created on the string worldsheet. The quark and antiquark are thus causally disconnected, and the string transitions to two straight strings. The forces acting on the endpoints vanish with a power law whose slope depends on the perturbations. The condition for this transition to occur is that energy injection exceeds the static energy between the quark-antiquark pair.

  1. Severe Hydronephrosis and Dysuria-Hematuria Syndrome after 20 Years of Bladder Exstrophy Correction: A Case Report

    PubMed Central

    Altobelli, Emanuela; Bove, Alfredo Maria; Sergi, Federico; Zullo, Marzio Angelo; Buscarini, Maurizio

    2012-01-01

    The aim of this paper is to report a case of severe hydronephrosis and incontinence 20 years after bladder exstrophy repair, managed successfully by secondary ureteroneocystostomy and by transurethral submucosal injection of Macroplastique. PMID:23198264

  2. Rhabdomyolysis and Cardiomyopathy in a 20-Year-Old Patient with CPT II Deficiency

    PubMed Central

    Vavlukis, M.; Eftimov, A.; Zafirovska, P.; Caparovska, E.; Pocesta, B.; Kedev, S.; Dimovski, A. J.

    2014-01-01

    Aim. To raise the awareness of adult-onset carnitite palmitoyltransferase II deficiency (CPT II) by describing clinical, biochemical, and genetic features of the disease occurring in early adulthood. Method. Review of the case characteristics and literature review. Results. We report on a 20-year-old man presenting with dyspnea, fatigue, fever, and myoglobinuria. This was the second episode with such symptoms (the previous one being three years earlier). The symptoms occurred after intense physical work, followed by a viral infection resulting in fever treated with NSAIDs. Massive rhabdomyolysis was diagnosed, resulting in acute renal failure necessitating plasmapheresis and hemodialysis, acute hepatic lesion, and respiratory insufficiency. Additionally, our patient had cardiomyopathy with volume overload. After a detailed workup, CPT II deficiency was suspected. We did a sequencing analysis for exons 1, 3, and 4 of the CPT II gene and found that the patient was homozygote for Ser 113 Leu mutation in exon 3 of the CPT II gene. The patient recovery was complete except for the cardiomiopathy with mildly impaired systolic function. Conclusion. Whenever a patient suffers recurrent episodes of myalgia, followed by myoglobinuria due to rhabdomyolysis, we should always consider the possibility of this rare condition. The definitive diagnose of this condition is achieved by genetic testing. PMID:24563797

  3. Annular Pancreas: A Cause of Gastric Outlet Obstruction in a 20-Year-Old Patient

    PubMed Central

    Alahmadi, Raha; Almuhammadi, Saud

    2014-01-01

    Patient: Female, 20 Final Diagnosis: Annular pancreas Symptoms: Food intolerance • vomiting Medication:— Clinical Procedure: — Specialty: Gastroenterology and Hepatology Objective: Congenital defects/diseases Background: Annular pancreas is a congenital anomaly that consists of a ring of pancreatic tissue partially or completely encircling the descending portion of the duodenum. It is formed due to the failure of the ventral bud to rotate, thus it elongates and encircles the upper part of the duodenum. It can present in a wide range of clinical severities, and can affect neonates to the elderly, making it difficult to diagnosis. Although diagnosis of annular pancreas can be made pre-operatively by upper GI series, upper GI endoscopy, or CT scan, 40% of diagnoses require surgery for confirmation. Case Report: We report the case of a 20-year-old woman presenting with history of vomiting and weight loss since childhood. We present the clinical characteristics, surgical management in the form of bypass procedure done through a duodenojujenostomy, and follow-up of the patient. Conclusions: Annular pancreas occasionally presents in adults. Variable presentations have been described in the literature, including pancreatic neoplasm, pancreatitis, obstructive jaundice, duodenal obstruction, and peptic ulcer diseases. Most studies of these lesions are single case reports or small series, which do not allow a surgeon to accumulate extensive experience; therefore, reliance on the combined experience of others in recognition and appropriate management has been the norm. PMID:25300027

  4. Cre-Lox Neurogenetics: 20 Years of Versatile Applications in Brain Research and Counting…

    PubMed Central

    Tsien, Joe Z.

    2016-01-01

    Defining and manipulating specific neurons in the brain has garnered enormous interest in recent years, because such an approach is now widely recognized as crucial for deepening our understanding of how the brain works. When I started exploring the Cre-loxP recombination for brain research in the early 1990s, it was written off as a dead-end project by a young fool. Yet over the past 20 years, Cre-lox recombination-mediated neurogenetics has emerged as one of the most powerful and versatile technology platforms for cell-specific gene knockouts, transgenic overexpression, Brainbow imaging, neural pathway tracing with retrovirus and CLARITY, chemical genetics, and optogenetics. Its popularity and greater utility in neuroscience research is also largely thanks to the NIH’s bold Blueprint for Neuroscience Research Initiative to launch several Cre-driver resource projects, as well as individual laboratories and private research organizations. With newly-discovered, genetically-encoded molecules that are capable of responding to sonar and magnetic stimulation, for sonogenetics or magnetogenetics, respectively, or detecting rapid voltage changes in neurons, Cre-lox neurogenetics will continue to aid brain research for years to come. PMID:26925095

  5. Evaluation of study patients with Lyme disease, 10-20-year follow-up.

    PubMed

    Kalish, R A; Kaplan, R F; Taylor, E; Jones-Woodward, L; Workman, K; Steere, A C

    2001-02-01

    To determine the long-term impact of Lyme disease, we evaluated 84 randomly selected, original study patients from the Lyme, Connecticut, region who had erythema migrans, facial palsy, or Lyme arthritis 10-20 years ago and 30 uninfected control subjects. The patients in the 3 study groups and the control group did not differ significantly in current symptoms or neuropsychological test results. However, patients with facial palsy, who frequently had more widespread nervous system involvement, more often had residual facial or peripheral nerve deficits. Moreover, patients with facial palsy who did not receive antibiotics for acute neuroborreliosis more often now had joint pain and sleep difficulty and lower scores on the body pain index and standardized physical component sections of the Short-Form 36 Health Assessment Questionnaire than did antibiotic-treated patients with facial palsy. Thus, the overall current health status of each patient group was good, but sequelae were apparent primarily among patients with facial palsy who did not receive antibiotics for acute neuroborreliosis.

  6. Mirror neurons (and beyond) in the macaque brain: an overview of 20 years of research.

    PubMed

    Casile, Antonino

    2013-04-12

    Mirror neurons are a class of neurons in the ventral pre-motor cortex (area F5) and inferior parietal lobule (area PFG) that respond during the execution as well as the observation of goal-directed motor acts. These intriguing response properties stirred an intense debate in the scientific community with respect to the possible cognitive role of mirror neurons. The aim of the present review is to contribute to this debate by providing, in a single paper, an extended summary of 20 years of neurophysiological research on mirror neurons in the macaque. To this end, I provide a comprehensive description of the methodology and the main results of each paper about mirror neurons published since their first report in 1992. Particular care was devoted in reporting the different response characteristics and the percentages of neurons exhibiting them in relation to the total number of studied neurons. Furthermore, I also discuss recent results indicating that mirror neurons might not be confined to areas F5 and PFG and that "mirroring" might not be limited to action observation. Finally, I offer a unifying framework for many of the results discussed here by speculating that a potential functional role of mirror neurons might be, during action observation, to generalize from the particular grasping movement being observed to the "concept" of grasping.

  7. A 20 Year Lifecycle Study for Launch Facilities at the Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Kolody, Mark R.; Li. Wenyan; Hintze, Paul E.; Calle, Luz-Marina

    2009-01-01

    The lifecycle cost analysis was based on corrosion costs for the Kennedy Space Center's Launch Complexes and Mobile Launch Platforms. The first step in the study involved identifying the relevant assets that would be included. Secondly, the identification and collection of the corrosion control cost data for the selected assets was completed. Corrosion control costs were separated into four categories. The sources of cost included the NASA labor for civil servant personnel directly involved in overseeing and managing corrosion control of the assets, United Space Alliance (USA) contractual requirements for performing planned corrosion control tasks, USA performance of unplanned corrosion control tasks, and Testing and Development. Corrosion control operations performed under USA contractual requirements were the most significant contributors to the total cost of corrosion. The operations include the inspection of the pad, routine maintenance of the pad, medium and large scale blasting and repainting activities, and the repair and replacement of structural metal elements. Cost data was collected from the years between 2001 and 2007. These costs were then extrapolated to future years to calculate the 20 year lifecycle costs.

  8. The problem of pattern and scale in ecology: what have we learned in 20 years?

    PubMed

    Chave, Jérôme

    2013-05-01

    Over the past 20 years, major advances have clarified how ecological patterns inform theory, and how in turn theory informs applied ecology. Also, there has been an increased recognition that the problem of scale at which ecological processes should be considered is critical if we are to produce general predictions. Ecological dynamics is always stochastic at small scales, but variability is conditional on the scale of description. The radical changes in the scope and aims of ecology over the past decades reflect in part the need to address pressing societal issues of environmental change. Technological advances in molecular biology, global positioning, sensing instrumentation and computational power should not be overlooked as an explanation for these radical changes. However, I argue that conceptual unification across ecology, genetics, evolution and physiology has fostered even more fertile questions. We are moving away from the view that evolution is played in a fixed ecological theatre: the theatre is being rapidly and relentlessly redesigned by the players themselves. The maintenance of ecosystem functions depends on shifts in species assemblages and on cellular metabolism, not only on flows of energy and matter. These findings have far reaching implications for our understanding of how ecosystem function and biodiversity will withstand (or not) environmental changes in the 21st century.

  9. Cre-Lox Neurogenetics: 20 Years of Versatile Applications in Brain Research and Counting….

    PubMed

    Tsien, Joe Z

    2016-01-01

    Defining and manipulating specific neurons in the brain has garnered enormous interest in recent years, because such an approach is now widely recognized as crucial for deepening our understanding of how the brain works. When I started exploring the Cre-loxP recombination for brain research in the early 1990s, it was written off as a dead-end project by a young fool. Yet over the past 20 years, Cre-lox recombination-mediated neurogenetics has emerged as one of the most powerful and versatile technology platforms for cell-specific gene knockouts, transgenic overexpression, Brainbow imaging, neural pathway tracing with retrovirus and CLARITY, chemical genetics, and optogenetics. Its popularity and greater utility in neuroscience research is also largely thanks to the NIH's bold Blueprint for Neuroscience Research Initiative to launch several Cre-driver resource projects, as well as individual laboratories and private research organizations. With newly-discovered, genetically-encoded molecules that are capable of responding to sonar and magnetic stimulation, for sonogenetics or magnetogenetics, respectively, or detecting rapid voltage changes in neurons, Cre-lox neurogenetics will continue to aid brain research for years to come. PMID:26925095

  10. How have researchers studied multiracial populations: A content and methodological review of 20 years of research

    PubMed Central

    Charmaraman, Linda; Woo, Meghan; Quach, Ashley; Erkut, Sumru

    2014-01-01

    The U. S. Census shows that the racial-ethnic make-up of over 9 million people (2.9% of the total population) who self-identified as multiracial is extremely diverse. Each multiracial subgroup has unique social and political histories that may lead to distinct societal perceptions, economic situations, and health outcomes. Despite the increasing academic and media interest in multiracial individuals, there are methodological and definitional challenges in studying the population resulting in conflicting representations in the literature. This content and methods review of articles on multiracial populations provides a comprehensive understanding of which multiracial populations have been included in research and how they have been studied both to recognize the emerging research and to identify gaps for guiding future research on this complex but increasingly visible population. We examine 125 U.S.-based peer-reviewed journal articles published over the past 20 years (1990–2009) containing 133 separate studies focused on multiracial individuals from primarily the fields of psychology, sociology, social work, education, and public health. Findings include (a) descriptive data regarding the sampling strategies, methodologies, and demographic characteristics of studies, including which multiracial subgroups are most studied, gender, age range, region of country, socioeconomic status; (b) major thematic trends in research topics concerning multiracial populations; (c) implications and recommendations for future studies. PMID:25045946

  11. A 20-Year-Old Retained Surgical Gauze Mimicking a Spinal Tumor: A Case Report

    PubMed Central

    Lee, Sungjoon; Kim, Bomi; Kim, Jung Soo

    2016-01-01

    A 79-year-old man visited our clinic complaining of lower back and left leg radiating pain that began 1 month prior to his presentation. He underwent surgery for lumbar disc herniation 20 years ago at another hospital. Magnetic resonance imaging revealed left-sided foraminal stenosis at L4-5. In addition, a paraspinal mass occupying the L4 spinous process and left lamina was observed. We subsequently performed an L4-5 decompression and fusion. During the operation, retained surgical gauze with granulation tissue was found. The term gossypiboma is used to define a mass lesion consisting of retained surgical gauzes and an adjacent foreign body reaction. Gossypibomas are uncommon in the paraspinal area and are mostly asymptomatic in chronic cases. Because there are no specific clinical or radiological signs, they can be confused with other tumorous conditions. Gossypibomas should be included in the differential diagnosis of paraspinal soft-tissue masses detected in patients with a history of prior spinal surgery. PMID:27799998

  12. Susac's Syndrome in a Patient Diagnosed with MS for 20 Years: A Case Report.

    PubMed

    Nazliel, Bijen; Akyol, Asli; Zeynep Batur Caglayan, Hale; Yildirim-Capraz, Irem; Irkec, Ceyla

    2014-01-01

    Susac's syndrome is an uncommon neurologic disorder of unknown cause. It has been described as a clinical triad of encephalopathy, hearing loss, and branch retinal artery occlusions. Clinically the diagnosis is difficult when the patient presents only a portion of a triad. We present a case with vision loss and sensorineural deafness and who had been diagnosed with MS for 20 years. Susac's syndrome is presumed to be an autoimmune endotheliopathy. Neurologic symptoms and signs are diffuse and multifocal, acute or subacute in onset, and progress during the active phase of the disease. In some patients the onset was stroke like and in others that of subacute dementia. Headache, often with migrainous features, was a prominent feature initially in more than one half of the patients. A high index of suspicion leading to correct diagnosis and early appropriate therapy may reduce the permanent sequel seen with this disease. Misdiagnosis is common. In patients in whom diagnosis and treatment are delayed permanent morbidity is higher in terms of visual loss, hearing loss, and neurologic debility. In patients in whom rapid diagnosis has led to early administration of immunosuppressive therapy, recovery can be almost complete. PMID:24716016

  13. [The Italian Places of Nicholas Green 20 years after his assassination].

    PubMed

    De Santo, Natale Gaspare; Scarabelli, Andrea; Citterio, Franco; De Santo, Luca S; De Rosa, Giusy

    2014-01-01

    Twenty years ago, Nicholas Green, a 7- year-old American boy was shot, while on vacation, on the Autostrada (motorway) Salerno to Reggio Calabria in Italy. His organs, with the consent of his parents, Reg and Maggie, were removed and 7 persons had their lives changed. In Italy in these last 20 years, organ donation has increased powerfully from 6.2 to 18.2 per million population with a peak at 20 in 2006. Reg and Maggie Green, after Nicholas death, started campaigning for organ donation by making full use of the media. Italian justice was efficient and the criminals were imprisoned quickly. With popular enthusiasm, a total of 103 places were dedicated to Nicholas (schools, halls, squares, streets, parks, gardens, private collections), a proof of great appreciation. Teaching organ donation to children, nurses and medical students is a powerful tool to convey the message of organ donation. To prevent opposition to organ removal when brain death occurs as Professor Francesco Casavola says signing for organ donation should be a family decision and laws for organ donation should be updated frequently in order to meet the progress of modernity.

  14. Optimising treatment strategies in spinal ependymoma based on 20years of experience at a single centre.

    PubMed

    Keil, Vera C; Schmitt, Anne J; Martin, Sean C; Cadoux-Hudson, Tom A D; Pereira, Erlick A C

    2016-07-01

    Spinal ependymomas are rare tumours, with total resection favoured where possible. Several case series assessing the outcome following neurosurgical treatment for spinal ependymoma advocate the usage of adjuvant radiotherapy in cases of subtotal resection, or in unencapsulated tumours. We assessed the outcome of 61 consecutive cases of spinal ependymoma in a single centre over a 20year period using a variety of outcome measures. Sex distribution was equal, with a mean age at surgery of 43.6years (range 5-76years). Overall, most tumours occurred in the lumbosacral region (70.5%), with fewer in the thoracic (27.9%) and cervical regions (18.0%). Myxopapillary features were seen in 41.0% of tumours, and were more common when occurring in the lumbar region (51.2%). Gross total resection was achieved in 52.5%, subtotal resection in 37.7% and biopsy alone in 9.8% of patients and 31.1% received adjuvant radiotherapy. Two-thirds of patients achieved an excellent post-operative neurological outcome (Frankel grade E). Tumour recurrence was rare. Gross total resection and good preoperative neurological condition were most strongly predictive of good outcome. Post-operative radiotherapy did not seem to confer survival benefit in this case series, even in cases of incomplete resection, leading us to question its utility for all cases of spinal cord ependymoma. PMID:26944215

  15. The European College of Veterinary Surgeons 1991-2011: a 20-year success story.

    PubMed

    Auer, Jörg A

    2011-08-01

    The first meeting leading to the formation of the European College of Veterinary Surgeons (ECVS) was held August 30/31, 1990 in Lenzburg, Switzerland. Specialists in small animal and large animal surgery from practice and academicians from many European countries were invited. The constitution was developed based on that of the American College of Veterinary Surgeons (ACVS). ECVS was founded during the ACVS European Surgical Forum in Nice in 1991. The provisional Board elected at this meeting stayed active during the initial 4 years to provide stability. For the 146 Charter Members to become a Diplomate, they had to pass an examination. Therefore, the ECVS is the only Specialty College that does not have a "Grand Father Clause." In 2000 ECVS, was the first College to acquire full recognition-status by the European Board of Specialization (EBVS), which underlines the leading role the surgeons play in the development of the European veterinary specialty colleges. Like its American Sister College, ECVS maintains high standards for surgical training programs for Residents and administers rigorous certifying examinations. It is appropriate to recall the facts that lead to foundation of ECVS on its 20-year anniversary.

  16. Responses of high-altitude graminoids and soil fungi to 20 years of experimental warming.

    PubMed

    Rudgers, Jennifer A; Kivlin, Stephanie N; Whitney, Kenneth D; Price, Mary V; Waser, Nickolas M; Harte, John

    2014-07-01

    High-elevation ecosystems are expected to be particularly sensitive to climate warming because cold temperatures constrain biological processes. Deeper understanding of the consequences of climate change will come from studies that consider not only the direct effects of temperature on individual species, but also the indirect effects of altered species interactions. Here we show that 20 years of experimental warming has changed the species composition of graminoid (grass and sedge) assemblages in a subalpine meadow of the Rocky Mountains, USA, by increasing the frequency of sedges and reducing the frequency of grasses. Because sedges typically have weak interactions with mycorrhizal fungi relative to grasses, lowered abundances of arbuscular mycorrhizal (AM) fungi or other root-inhabiting fungi could underlie warming-induced shifts in plant species composition. However, warming increased root colonization by AM fungi for two grass species, possibly because AM fungi can enhance plant water uptake when soils are dried by experimental warming. Warming had no effect on AM fungal colonization of three other graminoids. Increased AM fungal colonization of the dominant shrub Artemisia tridentata provided further grounds for rejecting the hypothesis that reduced AM fungi caused the shift from grasses to sedges. Non-AM fungi (including dark septate endophytes) also showed general increases with warming. Our results demonstrate that lumping grasses and sedges when characterizing plant community responses can mask significant shifts in the responses of primary producers, and their symbiotic fungi, to climate change.

  17. Cre-Lox Neurogenetics: 20 Years of Versatile Applications in Brain Research and Counting….

    PubMed

    Tsien, Joe Z

    2016-01-01

    Defining and manipulating specific neurons in the brain has garnered enormous interest in recent years, because such an approach is now widely recognized as crucial for deepening our understanding of how the brain works. When I started exploring the Cre-loxP recombination for brain research in the early 1990s, it was written off as a dead-end project by a young fool. Yet over the past 20 years, Cre-lox recombination-mediated neurogenetics has emerged as one of the most powerful and versatile technology platforms for cell-specific gene knockouts, transgenic overexpression, Brainbow imaging, neural pathway tracing with retrovirus and CLARITY, chemical genetics, and optogenetics. Its popularity and greater utility in neuroscience research is also largely thanks to the NIH's bold Blueprint for Neuroscience Research Initiative to launch several Cre-driver resource projects, as well as individual laboratories and private research organizations. With newly-discovered, genetically-encoded molecules that are capable of responding to sonar and magnetic stimulation, for sonogenetics or magnetogenetics, respectively, or detecting rapid voltage changes in neurons, Cre-lox neurogenetics will continue to aid brain research for years to come.

  18. Transconjunctival Approach for Zygomatic Fracture: A Single Surgeon’s Experience of More Than 20 Years

    PubMed Central

    Watanabe, Hidetaka; Masumoto, Kazuyuki; Chuman, Takahiro; Satake, Yoshiyasu; Yanai, Tetsu; Harada, Yoshimi; Ishihara, Yasuhiro; Kikuchi, Mamoru

    2016-01-01

    Background: To let experts evaluate a single surgeon’s experience with a combined transconjunctival and intraoral upper vestibular approach in the repair of zygomatic fractures encountered in 46 East Asian patients whom he treated over the past 20 years. Methods: Patients were identified from a database, and a retrospective case note review was conducted. A total of 67 conjunctival and secondary incisions were made on 46 patients for repair of zygomatic fractures. All operative procedures were performed using a combination of transconjunctival and intraoral upper vestibular approaches to repair zygomatic fractures. Results: The infraorbital rim and/or lateral buttress and/or lateral orbit was stabilized with titanium miniplates in 28 patients and absorbable miniplates in 11 patients. Seven patients required only reduction technique with no need of plates. Four cases needed additional canthotomy besides a conjunctival approach. No ectropion or entropion developed in any of the patients. Complications included eyelid laceration during surgery (n = 1), herniation of the conjunctiva (n = 1), temporary pyogenic granuloma of the conjunctiva after surgery (n = 1), and temporary entropion in a secondary incision (n = 1). Conclusions: A combined transconjunctival and intraoral upper vestibular approach in repairing zygomatic fractures is simple, easy, and effective, leaving no conspicuous facial scars. It is vitally important, however, that the surgeon masters the technique of transconjunctival approach well before he has good results in East Asian patients. PMID:27482496

  19. [Clinical study of parotid tumors: a 20 year statistical analysis of 633 cases].

    PubMed

    Kakimoto, S; Iwai, H; Kumazawa, H; Nakamura, A; Yukawa, H; Baba, K; Asako, M; Yamashita, T

    1999-06-01

    During the 20 years from 1977 to 1996, 633 cases underwent excisions of parotid tumors (539 benign and 94 malignant) in the department of Otolaryngology of Kansai Medical University. The incidence of Warthin's tumors in the years from (1987 to 1996) was higher than that in the years from 1977 to 1986. On the other hand, the incidence of mucoepidermoid carcinomas was less than in previous reports. Tumors accompanied with spontaneous pain or facial nerve palsy and with invasion to both lobes frequently indicated malignancy. Facial nerve palsy caused by either benign or malignant tumors before operation showed no improvement after surgery. The incidences of facial nerve palsy (1.0% in benign, and 18.3% in malignant) and Frey's syndrome (17.8% in benign, and 18.3% in malignant) after surgery were lower than those in other reports of both benign and malignant tumors. Five-year mortality was 76.1%. All deaths that occurred five years after operation involved highly grade malignant tumors. PMID:10429434

  20. Choledochal cysts in infants and children: experiences over a 20-year period at a single institution.

    PubMed

    Hung, Min-Hsuan; Lin, Lung-Huang; Chen, Der-Fang; Huang, Ching-Shui

    2011-09-01

    This analysis was undertaken to compare the clinicopathological features of infants with choledochal cysts to those of older children with these entities and to evaluate the surgical outcomes for both subject groups. The medical records of all children admitted to the Cathay General Hospital with choledochal cysts over a 20-year period were retrospectively reviewed. Twenty-five subjects were included and divided into the infant (<1 year at presentation; 8 subjects) and classical pediatric (1-18 years at presentation; 17 subjects) groups. Anatomical subtypes were: IA (16), IC (6), and IVA (3). The median biliary amylase value was markedly elevated for the pediatric group but not for the infant group. Most (82.4%) patients in the pediatric group, but none in the infant group, presented with abdominal pain. Jaundice and clay-colored stool were present in all patients in the infant group but only 35% of those in the pediatric group. All patients underwent choledochocystectomy and Roux-en-Y hepaticojejunostomy with good outcomes. Neonates/infants with choledochal cysts present differently from older children with these entities. Amylase measurements may serve to distinguish biliary atresia with cystic dilatation from choledochal cyst in neonates/infants. Prognosis following radical cyst excision and reconstruction with Roux-en-Y hepaticojejunostomy is excellent. PMID:21350805

  1. A 20-year H2O maser monitoring program with the Medicina 32-m telescope

    NASA Astrophysics Data System (ADS)

    Brand, J.; Felli, M.; Cesaroni, R.; Codella, C.; Comoretto, G.; Di Franco, S.; Massi, F.; Moscadelli, L.; Nesti, R.; Olmi, L.; Palagi, F.; Palla, F.; Panella, D.; Valdettaro, R.

    2007-03-01

    The Arcetri/Bologna H2O maser group has been monitoring the 1.3-cm water maser emission from a sample of 43 star-forming regions (SFRs) and 22 late-type stars for about 20 years at a sampling rate of 4-5 observations each year, using the 32-m Medicina Radio Telescope (HPBW 1.‧9 at 22 GHz). For the late-type stars we observe representative samples of OH/IR-stars, Mira's, semi-regular variables, and supergiants. The SFR-sample spans a large interval in FIR luminosity of the associated Young Stellar Object (YSO), from 20 L to 1.5 × 106 L, and offers a unique data base for the study of the long-term (years) variability of the maser emission in regions of star formation. This presentation concerns only the masers in SFRs. The information obtained from single-dish monitoring is complementary to what is extracted from higher-resolution (VLA and VLBI) observations, and can better explore the velocity domain and the long-term variability therein. We characterize the variability of the sources in various ways and we study how it depends on the luminosity and other properties of the associated YSO and its environment.

  2. 20 years of ECRH at W7-A and W7-AS

    NASA Astrophysics Data System (ADS)

    Erckmann, V.; Laqua, H. P.; Maaßberg, H.; Marushchenko, N. B.; Kasparek, W.; Müller, G. A.

    2003-11-01

    Basic research on high-power ECRH started 20 years ago at IPP using 28 GHz pulses with 200 kW for 40 ms at the W7-A stellarator. These pilot experiments triggered a strong activity of exploration of the unique capabilities of localized heating and current drive. The achievements in physics were strongly linked with progress in source and transmission line technology. The capability and versatility of ECRH are reviewed using W7-A and W7-AS as example experiments; the latter was shut down on July 31, 2002. The milestone achievements are discussed. Standard heating scenarios such as O-mode and X-mode as well as advanced scenarios like mode-conversion heating via the O-X-B process at different harmonics were investigated and selected results are presented. First experiments with current drive by Bernstein-waves are reported. The physics of wave interaction with stellarator-specific trapped particle populations is discussed. The results from W7-A and W7-AS establish the experimental and technological bases for the 10 MW, CW ECRH system at W7-X, which aims to demonstrate the inherent steady-state capability of stellarators.

  3. How have researchers studied multiracial populations? A content and methodological review of 20 years of research.

    PubMed

    Charmaraman, Linda; Woo, Meghan; Quach, Ashley; Erkut, Sumru

    2014-07-01

    The U.S. Census shows that the racial-ethnic makeup of over 9 million people (2.9% of the total population) who self-identified as multiracial is extremely diverse. Each multiracial subgroup has unique social and political histories that may lead to distinct societal perceptions, economic situations, and health outcomes. Despite the increasing academic and media interest in multiracial individuals, there are methodological and definitional challenges in studying the population, resulting in conflicting representations in the literature. This content and methods review of articles on multiracial populations provides a comprehensive understanding of which multiracial populations have been included in research and how they have been studied, both to recognize emerging research and to identify gaps for guiding future research on this complex but increasingly visible population. We examine 125 U.S.-based peer-reviewed journal articles published over the past 20 years (1990 to 2009) containing 133 separate studies focused on multiracial individuals, primarily from the fields of psychology, sociology, social work, education, and public health. Findings include (a) descriptive data regarding the sampling strategies, methodologies, and demographic characteristics of studies, including which multiracial subgroups are most studied, gender, age range, region of country, and socioeconomic status; (b) major thematic trends in research topics concerning multiracial populations; and (c) implications and recommendations for future studies.

  4. A systematic review of 1143 parapharyngeal space tumors reported over 20 years.

    PubMed

    Riffat, Faruque; Dwivedi, Raghav C; Palme, Carsten; Fish, Brian; Jani, Piyush

    2014-05-01

    Parapharyngeal space tumours are rare and most clinicians will only see a small number during their career. We performed a systematic review of 1143 parapharyngeal space tumors published in the past 20 years to increase cumulative experience. A systematic literature review was performed and data on histological diagnosis, presentation, surgical approach and postoperative complications of cases published between 1989 and 2009 were compiled and reviewed. The systematic review identified a total of 1143 parapharyngeal space tumors presented in 17 studies. A majority (82%) were benign and 18% were malignant. The most common presentation was a cervical mass (50%) or an intraoral mass (47%). Approximately 70 different histologic subtypes of parapharyngeal space tumors were reported in the cumulative series. The most common primary lesion was a pleomorphic adenoma (34%). Ninety-five percent of patients underwent surgery. The most frequent approach and used to excise the lesions was the cervical approach (48%) and the commonest complication was the vagus nerve injury seen in 14% of the cases.

  5. Short Implants in Partially Edentuolous Maxillae and Mandibles: A 10 to 20 Years Retrospective Evaluation

    PubMed Central

    Lops, Diego; Bressan, Eriberto; Pisoni, Gianluca; Cea, Niccolò; Corazza, Boris; Romeo, Eugenio

    2012-01-01

    Purpose. Evaluation of the short implant (8 mm in height) long-term prognosis and of the implant site influence on the prognosis. Methods. A longitudinal study was carried out on 121 patients (57 males and 64 females) consecutively treated with 257 implants. 108 implants were short. Results. Four (3.6%) short implants supporting fixed partial prostheses failed. Similarly, three standard implants supporting fixed partial prostheses and one supporting single-crown prosthesis failed. Mean marginal bone loss (MBL) and probing depth (PD) of short and standard implants were statistically comparable (P > .05). The 20-year cumulative survival rates of short and standard implants were 92.3 and 95.9%, respectively. The cumulative success rates were 78.3 and 81.4%. The survival rates of short implants in posterior and anterior regions were comparable: 95 and 96.4%, respectively. The difference between survival rates was not significant (P > .05). Conclusions. The high reliability of short implants in supporting fixed prostheses was confirmed. Short and standard implants long-term prognoses were not significantly different. The prognosis of short implants in posterior regions was comparable to that of in anterior regions. Nevertheless, a larger sample is required to confirm this trend. PMID:22829823

  6. Thermal history of the Sabero Coalfield (Southern Cantabrian Zone, NW Spain) as revealed by apatite fission track analyses from tonstein horizons: implications for timing of coalification

    NASA Astrophysics Data System (ADS)

    Botor, Dariusz; Anczkiewicz, Aneta A.

    2015-10-01

    Apatite fission track (AFT) central ages from Carboniferous (Stephanian) tonsteins of the Sabero Coalfield, NW Spain, range from 140.8 ± 7.5 to 65.8 ± 8.1 Ma (Cretaceous), with mean c-axis projected track length values ranging from 12.5 to 13.4 μm. Mean random vitrinite reflectance ( R r) of these samples ranges from 0.91 to 1.20 %, which can be translated into maximum palaeotemperatures of ca. 130 to 180 °C. All analysed samples experienced substantial post-depositional annealing. The considerably younger AFT ages compared to the depositional ages of the samples and R r data indicate the certainty of the occurrence of at least one heating event after the deposition of strata. The unimodal track length distributions, the relatively short mean track length, and the rather low standard deviation (SD) (1.0-1.6 μm) indicate a relatively simple thermal history that could be related to the post-Late Variscan heating event followed by prolonged residence in the apatite partial annealing zone (APAZ). Geological data combined with thermal models of AFT data indicate that Stephanian strata reached the maximum palaeotemperatures in the Permian period, which was therefore the major time of the coalification processes. The Permian magmatic activity was responsible for a high heat flow, which, with the added effect of sedimentary burial, could account for the resetting of the AFT system. It appears that the fault-related hydrothermal activity could have redistributed heat in areas of significant subsidence. Cooling occurred in the Triassic-Cretaceous times after a high heat flow Permian regime. A post-Permian maturation of the Stephanian organic matter is not very likely, since there is no evidence of a high Mesozoic burial that was sufficient to cause a significant increase in the palaeotemperatures. Finally, exhumation and associated erosion rates may possibly have been faster in the Tertiary, causing the present exposure of the studied rocks.

  7. Management of the infected median sternotomy wound with muscle flaps. The Emory 20-year experience.

    PubMed Central

    Jones, G; Jurkiewicz, M J; Bostwick, J; Wood, R; Bried, J T; Culbertson, J; Howell, R; Eaves, F; Carlson, G; Nahai, F

    1997-01-01

    OBJECTIVE: The purpose of the study is to define those patient variables that contribute to morbidity and mortality of median sternotomy wound infection and the results of treatment by debridement and closure by muscle flaps. BACKGROUND: Infection of the median sternotomy wound after open heart surgery is a devastating complication associated with significant mortality. Twenty years ago, these wounds were treated with either open packing or antibiotic irrigation, with a mortality approaching 50% in some series. In 1975, the authors began treating these wounds with radical sternal debridement followed by closure using muscle or omental flaps. The mortality of sternal wound infection has dropped to < 10%. METHODS: The authors' total experience with 409 patients treated over 20 years is described in relation to flap choices, hospital days after sternal wound closure, and incidence rates of morbidity and mortality. One hundred eighty-six patients treated since January 1988 were studied to determine which patient variables had impact on rates of flap closure complications, recurrent sternal wound infection, or death. Variables included obesity, history of smoking, hypertension, diabetes, poststernotomy septicemia, internal mammary artery harvest, use of intra-aortic balloon pump, and perioperative myocardial infarction and were analyzed using chi square tests. Fisher's exact tests, and multivariable logistic regression analysis. RESULTS: The mortality rate over 20 years was 8.1% (33/49). Additional procedures for recurrent sternal wound infection were necessary in 5.1% of patients. Thirty-one patients (7.6%) required treatment for hematoma, and 11 patients (2.7%) required hernia repair. Among patients treated since 1988, variables strongly associated with mortality were septicemia (p < 0.00001), perioperative myocardial infarction (p = 0.006), and intra-aortic balloon pump (p = 0.0168). Factors associated with wound closure complications were intra-aortic balloon pump

  8. When folic acid fails: Insights from 20 years of neural tube defect surveillance in South Carolina.

    PubMed

    Bupp, Caleb P; Sarasua, Sara M; Dean, Jane H; Stevenson, Roger E

    2015-10-01

    Neural tube defects (NTDs) are the most common of the severe malformations of the brain and spinal cord. Increased maternal intake of folic acid (FA) during the periconceptional period is known to reduce NTD risk. Data from 1046 NTD cases in South Carolina were gathered over 20 years of surveillance. It was possible to determine maternal periconceptional FA use in 615 NTD-affected pregnancies. In 163 occurrent (26.9%) and two recurrent (22%) NTD cases, the mothers reported periconceptional FA use. These women were older and more likely to be white. Maternal periconceptional FA usage was reported in 40.4% of cases of spina bifida with other anomalies but in only 25.2% of isolated spina bifida cases (P = 0.02). This enrichment for associated anomalies was not noted among cases of anencephaly or of encephalocele. Among the 563 subsequent pregnancies to mothers with previous NTD-affected pregnancies, those taking FA had a 0.4% NTD recurrence rate, but the recurrence without FA was 8.5%. NTDs with other associated findings were less likely to be prevented by FA, suggesting there is a background NTD rate that cannot be further reduced by FA. Nonetheless, the majority (73.9%) of NTDs in pregnancies in which the mothers reported periconceptional FA use were isolated NTDs of usual types. Cases in which FA failed in prevention of NTDs provide potential areas for further study into the causation of NTDs. The measures and techniques implemented in South Carolina can serve as an effective and successful model for prevention of NTD occurrence and recurrence. PMID:26108864

  9. Oro-facial injuries in Central American and Caribbean sports games: a 20-year experience.

    PubMed

    Amy, Enrique

    2005-06-01

    Dental services in sports competitions in the Games sponsored by the International Olympic Committee are mandatory. In every Central American, Pan American and Olympic Summer Games, as well as Winter Games, the Organizing Committee has to take all the necessary measures to assure dental services to all competitors. In all Olympic villages, as part of the medical services, a dental clinic is set up to treat any dental emergency that may arise during the Games. Almost every participating country in the Games has its own medical team and some may include a dentist. The major responsibilities of the team dentist as a member of the national sports delegation include: (i) education of the sports delegation about different oral and dental diseases and the illustration of possible problems that athletes or other personnel may encounter during the Games, (ii) adequate training and management of orofacial trauma during the competition, (iii) knowledge about the rules and regulations of the specific sport that the dentist is working, (iv) understanding of the anti-doping control regulations and procedures, (v) necessary skills to fabricate a custom-made and properly fitted mouth guard to all participants in contact or collision sports of the delegation. This study illustrates the dental services and occurrence of orofacial injury at the Central American and Caribbean Sports Games of the Puerto Rican Delegation for the past 20 years. A total of 2107 participants made up the six different delegations at these Games. Of these 279 or 13.2% were seen for different dental conditions. The incidence of acute or emergency orofacial conditions was 18 cases or 6% of the total participants. The most frequent injury was lip contusion with four cases and the sport that experienced more injuries was basketball with three cases. PMID:15876321

  10. Head and Neck Schwannomas: 20-Year Experience of a Single Institution Excluding Cutaneous and Acoustic Sites.

    PubMed

    Butler, Randall T; Patel, Rajiv M; McHugh, Jonathan B

    2016-09-01

    While head and neck sites comprise the most common location of schwannomas, clinicopathologic data regarding those tumors occurring in non-acoustic and non-cutaneous locations are relatively sparse. In this study, therefore, we sought to examine retrospectively the clinical and pathologic features of head and neck schwannomas excised at our institution over a 20-year period. During this period, we identified a total cohort of 85 patients, which included 36 males (42.4 %) and 49 females with average age of 41.3 years, the majority of which presented asymptomatically with a mass. Localized symptoms were, however, associated with all of the schwannomas that arose in the oral cavity and larynx, while tumors within or adjacent to bone were often associated with neurologic complaints (7 of 15 such tumors [46.7 %]). Clinical follow-up data was available in 86.4 % of all cases and demonstrated no recurrences or mortality. Pathologically, the microscopic features were characteristic of those well-described for schwannomas in other sites, including alternating Antoni A and B areas and the presence of degenerative changes. Tumor encapsulation, however, was variable and was completely absent in schwannomas of the nasal cavity, paranasal sinuses, and larynx. Additionally, a significant minority of the tumors (28.2 %) exhibited foci that resembled neurofibroma. Non-acoustic, non-cutaneous schwannomas of the head and neck appear to have clinicopathologic features similar to their soft tissue counterparts with some subsite variation in presentation and/or microscopic features. PMID:26747460

  11. 20 years of long-term atrazine monitoring in a shallow aquifer in western Germany.

    PubMed

    Vonberg, David; Vanderborght, Jan; Cremer, Nils; Pütz, Thomas; Herbst, Michael; Vereecken, Harry

    2014-03-01

    Atrazine was banned in Germany in 1991 due to findings of atrazine concentrations in ground- and drinking waters exceeding threshold values. Monitoring of atrazine concentrations in the groundwater since then provides information about the resilience of the groundwater quality to changing agricultural practices. In this study, we present results of a monitoring campaign of atrazine concentrations in the Zwischenscholle aquifer. This phreatic aquifer is exposed to intensive agricultural land use and susceptible to contaminants due to a shallow water table. In total 60 observation wells (OWs) have been monitored since 1991, of which 15 are sampled monthly today. Descriptive statistics of monitoring data were derived using the "regression on order statistics" (ROS) data censoring approach, estimating values for nondetects. The monitoring data shows that even 20 years after the ban of atrazine, the groundwater concentrations of sampled OWs remain on a level close to the threshold value of 0.1 μg l(-1) without any considerable decrease. The spatial distribution of atrazine concentrations is highly heterogeneous with OWs exhibiting permanently concentrations above the regulatory threshold on the one hand and OWs were concentrations are mostly below the limit of quantification (LOQ) on the other hand. A deethylatrazine-to-atrazine ratio (DAR) was used to distinguish between diffuse - and point-source contamination, with a global mean value of 0.84 indicating mainly diffuse contamination. Principle Component Analysis (PCA) of the monitoring dataset demonstrated relationships between the metabolite desisopropylatrazine, which was found to be exclusively associated with the parent compound simazine but not with atrazine, and between deethylatrazine, atrazine, nitrate, and the specific electrical conductivity. These parameters indicate agricultural impacts on groundwater quality. The findings presented in this study point at the difficulty to estimate mean concentrations

  12. [The agroecosystems flora status in restricted zone 20 years after the Chernobyl NPP accident].

    PubMed

    Sapegin, L M; Daĭneko, N M; Timofeev, S F

    2008-01-01

    The article presents the results of studying on agroecosystems flora status in restricted zone 20 years after the Chernobyl accident. There were preliminary identified 8 agroecosystems associations by Broaun-Blanquet ecologo-floristic classification: Phalacrolometum septentrionale, Agrostio tenuis Calamagrostietum epigeii, Agrostio tenuis--Elytrigietum repentis, Poo pratensis--Bromopsietum inermis, Poo pratensis--Dactylidetum glomeratae, Poo pratensis--Agrostietum tenuis, Elytrigio repentis--Poetum pratensis, Caricetum hirtae. First three associations were attributed to Agropyretea repentis class, to Agropyretalia repentis order, Convolvulo--Agropyrion union. We consider the association Phalacrolometum septentrionale as the initial stage of agroscosystems overgrowing which is continued with increase of its demonstration in association Agrostio tenuis--Calamagrostietum epigeii and Agrostio tenuis--Elytrigietum repentis. The associations Poo pratensis--Bromopsietum inermis, Poo pratensis--Dactylidetum glomeratae, Poo pratensis--Agrostietum tenuis and Elytrigio repentis--Poetum pratensis we attributed to class Molinio--Arrhenatheretea, to order Arrhenatheretalia and Festuncion pratensis union. The association Caricetum hirtae was attributed to class Plantaginetea majoris, to order Plantaginetalia majoris and to union Agrapyro--Rumicion crispi. For each of the allocated associations and rye sowing there was provided brief characteristic, including 137Cs and 90Sr radionuclids content in soil and air-dry herbage mass. During the period of studies there was marked stable soil and air-dry herbage mass contamination by radionuclides at absence of grass stabilization of studied agroecosystems. The limiting factor on using of meadow agroecosystems herbages is their high level of contamination by 90Sr. The herbage can be used only for obtaining of milk-raw material for processing. PMID:18666581

  13. The evolving role of data scientist during 20 years of the British Atmospheric Data Centre (Invited)

    NASA Astrophysics Data System (ADS)

    Pascoe, S.; Parton, G.; Pascoe, C.; Guillory, A.; da Costa, E. D.

    2013-12-01

    In 2014 The British Atmospheric Data Centre (BADC), now part of the Centre of Environmental Data Archival (CEDA), will celebrate its 20th anniversary. During its lifetime, most BADC staff have defined themselves as data scientists by virtue of being scientists by background and "data workers" by practice. However, the definition of data scientist has been ill defined until recently. As the term has become popularised in the world of business and general information technology, we ask ourselves to what extent the popular definition fits our profession. We observe that data science, as practised at CEDA, encompasses several roles which overlap and compliment each other as we strive to be enablers of data exploitation. For us a data scientist's skills include elements of data curation, software engineering, data infrastructure management and data-intensive research. As data science has evolved the balance between these roles has shifted in response to changes in technology, demands of the research community and funding drivers. We have had to balance our role as enablers of data exploitation, by providing services and infrastructure to the geo-science community, with our role as pioneers of data exploitation itself. By telling the story of how these roles have evolved during the 20 year history of the BADC, we aim to explore the maturing role of data scientist as practised within the geo-sciences and contrast that role with its recently popularised usage. Looking forward we will address questions about how centres of expertise, such as CEDA, can best increase the data capabilities of geo-science research as a whole in order to facilitate the transition to data-intensive science.

  14. The Epidemiology and Clinical Spectrum of Melioidosis: 540 Cases from the 20 Year Darwin Prospective Study

    PubMed Central

    Currie, Bart J.; Ward, Linda; Cheng, Allen C.

    2010-01-01

    Background Over 20 years, from October 1989, the Darwin prospective melioidosis study has documented 540 cases from tropical Australia, providing new insights into epidemiology and the clinical spectrum. Principal Findings The principal presentation was pneumonia in 278 (51%), genitourinary infection in 76 (14%), skin infection in 68 (13%), bacteremia without evident focus in 59 (11%), septic arthritis/osteomyelitis in 20 (4%) and neurological melioidosis in 14 (3%). 298 (55%) were bacteremic and 116 (21%) developed septic shock (58 fatal). Internal organ abscesses and secondary foci in lungs and/or joints were common. Prostatic abscesses occurred in 76 (20% of 372 males). 96 (18%) had occupational exposure to Burkholderia pseudomallei. 118 (22%) had a specific recreational or occupational incident considered the likely infecting event. 436 (81%) presented during the monsoonal wet season. The higher proportion with pneumonia in December to February supports the hypothesis of infection by inhalation during severe weather events. Recurrent melioidosis occurred in 29, mostly attributed to poor adherence to therapy. Mortality decreased from 30% in the first 5 years to 9% in the last five years (p<0.001). Risk factors for melioidosis included diabetes (39%), hazardous alcohol use (39%), chronic lung disease (26%) and chronic renal disease (12%). There was no identifiable risk factor in 20%. Of the 77 fatal cases (14%), 75 had at least one risk factor; the other 2 were elderly. On multivariate analysis of risk factors, age, location and season, the only independent predictors of mortality were the presence of at least one risk factor (OR 9.4; 95% CI 2.3–39) and age ≥50 years (OR 2.0; 95% CI 1.2–2.3). Conclusions Melioidosis should be seen as an opportunistic infection that is unlikely to kill a healthy person, provided infection is diagnosed early and resources are available to provide appropriate antibiotics and critical care. PMID:21152057

  15. MEST-Tyche will take its dark comets to impact our solar system in 20 years

    NASA Astrophysics Data System (ADS)

    Cao, Dayong

    2012-03-01

    Tyche has many dark comets like Oort cloud. It went near our solar system every 25-27 million years. It could take its dark comets to impact our earth. Tyche and its dark comet absorb light like a dark light which is a negative black-body radiation. (1) Eddν=-c1dνd^3dνe^c2dνd/Td-1. Among it, Ed: the dark energy, νd: the dark frequence, Td: the dark temperature, c1d,c2d: the constant. So when they go near us, their wave has a against Doppler redshift as 0.000165. And they will inbreak solar system at the rate of 99AU/y, from the distance of 1,500AU and in 20 years. It can cause the broken ozonosphere, the lithosphere to crack, many big activity volcanic and the continental drift. And it can darked the light and colded the climate to the Great Ice Age. Not only it will break our environment by a special ``nuclear explosion'' under low temperature, but also the dark life will change the Genetic code of our life. So it will kill many lives and will produce new life. So it could trigger the Mass Extinction. We can bulid up a new pair of nuclear reactor (include dark nuclear energy) to drive a universal craft and can change the orbit of our earth for evading the impaction. We need a new life-information technology to develop our life and consciousness.

  16. Assessing the global zoo response to the amphibian crisis through 20-year trends in captive collections.

    PubMed

    Dawson, Jeff; Patel, Freisha; Griffiths, Richard A; Young, Richard P

    2016-02-01

    Global amphibian declines are one of the biggest challenges currently facing the conservation community, and captive breeding is one way to address this crisis. Using information from the International Species Information System zoo network, we examined trends in global zoo amphibian holdings across species, zoo region, and species geographical region of origin from 1994 to 2014. These trends were compared before and after the 2004 Global Amphibian Assessment to assess whether any changes occurred and whether zoo amphibian conservation effort had increased. The numbers of globally threatened species (GTS) and their proportional representation in global zoo holdings increased and this rate of increase was significantly greater after 2004. North American, European, and Oceanian GTS were best represented in zoos globally, and proportions of Oceanian GTS held increased the most since 2004. South American and Asian GTS had the lowest proportional representation in zoos. At a regional zoo level, European zoos held the lowest proportions of GTS, and this proportion did not increase after 2004. Since 1994, the number of species held in viable populations has increased, and these species are distributed among more institutions. However, as of 2014, zoos held 6.2% of globally threatened amphibians, a much smaller figure than for other vertebrate groups and one that falls considerably short of the number of species for which ex situ management may be desirable. Although the increased effort zoos have put into amphibian conservation over the past 20 years is encouraging, more focus is needed on ex situ conservation priority species. This includes building expertise and capacity in countries that hold them and tracking existing conservation efforts if the evidence-based approach to amphibian conservation planning at a global level is to be further developed.

  17. Factors Associated with Persistant and Non-Persistant Chronic Constipation, Over 20 Years

    PubMed Central

    Choung, Rok Seon; Locke, G. Richard.; Rey, Enrique; Schleck, Cathy D.; Baum, Charles; Zinsmeister, Alan R.; Talley, Nicholas J.

    2012-01-01

    Background & Aims The prevalence of chronic constipation (CC) has been reported to be as high as 20% in the general population, but little is known about its natural history. We estimated the natural history of CC and characterized features of persistent CC and non-persistent CC, compared to individuals without constipation. Methods In a prospective cohort study, we analyzed data collected from multiple, validated surveys (minimum of 2) of 2853 randomly selected subjects, over a 20-year period (median, 11.6 years). Based on responses, subjects were characterized as having persistent CC, non-persistent CC, or no constipation. We assessed the association between constipation status and potential risk factors using logistic regression models, adjusting for age and sex. Results Of the respondents, 84 had persistent CC (3%), 605 had non-persistent CC (21%), and 2164 had no symptoms of constipation (76%). High scores from the somatic symptom checklist (odds ratio [OR] =2.1; 95% confidence interval [CI], 1.3–3.4) and frequent doctor visits (OR=2.0; 95% CI, 1.0–3.8) were significantly associated with persistent CC, compared to subjects with no constipation symptoms. The only factor that differed was increased use of laxatives or fiber among subjects with persistent CC (OR=3.0; 95% CI, 1.9–4.9). Conclusion The prevalence of constipation might be exaggerated—the proportion of the population with persistent CC is low (3%). Patients with persistent and non-persistent CC have similar clinical characteristics, although individuals with persistent CC use more laxatives or fiber. CC therefore appears and disappears among certain patients, but we do not have enough information to identify these individuals in advance. PMID:22289877

  18. Radiographic findings on 3rd molars removed in 20-year-old men.

    PubMed

    Rajasuo, Ari; Peltola, Jaakko; Ventä, Irja; Murtomaa, Heikki

    2003-10-01

    In this study we assess radiographic findings characteristic of mandibular 3rd molars that had required either routine or surgical extraction. X-ray findings relating to acute pericoronitis were also examined. The material was collected by investigating patient records and rotational panoramic radiographs of 20-year-old Finnish male conscripts (n = 738) treated during military service because of 3rd-molar-related problems. The follicle around the crown of mandibular 3rd molars with acute pericoronitis was enlarged in 19% of cases and in 13% of chronic symptom-free pericoronitis cases (not statistically significant difference). Mandibular 3rd molars extracted surgically were more often mesially inclined than those extracted routinely (61% vs. 23%; P < 0.001), partially or totally intrabony impacted (92% vs. 66%; P < 0.001) and deep situated (on average 4.2 mm vs. 2.5 mm under the occlusal plane). Surgical extraction was also associated with the roots completely developed [92% vs. 84% of the teeth routinely extracted, odds ratio (OR) 2.6, 95% confidence interval (CI) 1.2-5.5] and with the absence of radiographic pericoronitis [around 27% vs. 39% of the teeth routinely extracted (OR 0.5, 95% CI 0.3-0.8)]. In 86% of cases the space between 2nd molar and ramus of the mandible was narrower than the 3rd molar extracted surgically, whereas this was 62% in routine extraction cases (P < 0.001). We conclude that there are some typical 3rd-molar findings in rotational panoramic radiographs that show a need for surgical extraction.

  19. Dental health status among sensory impaired and blind institutionalized children aged 6 to 20 years

    PubMed Central

    Sanjay, Venkataraam; Shetty, Sumanth M; Shetty, Rashmi G; Managoli, Noopur A; Gugawad, Sachin C; Hitesh, D

    2014-01-01

    Background: This study was planned to assess the dental caries status among disabled children as dental health is an integral part of general body health and this group is deprived of health care needs. Materials & Methods: A sample of 310 disabled children was gathered including 195- Hearing impaired, 115 – blind. Of which 226 were males and 84 were females. A study questionnaire was prepared to include demographic information and WHO oral health assessment form (1997) to record dental caries status.Data was analysed using student’s test and ANOVA test was used at p≤0.05. Results: The overall mean for DMFT scores for males and females was 2.11 (1.753) and 1.75 (1.275) respectively. Similarly overall mean for dft was 0.31 (0.254) for males and 0.27 (0.143) for females. Mean DMFT of blind students was more as compared to hearing impaired ones as 2.16 (2.005) and 1.80 (1.264) respectively. Age factor showed a significant increase in the mean DMFT scores with advancing age at p ≤ 0.001. Conclusion: Overall mean scores of caries was very high and it increased with increasing age. Blind children experienced more caries then hearing impaired children in permanent, whereas it was opposite in primary dentition. So there is urgent need of both comprehensive and incremental dental care for this subgroup of population. How to cite the article: Sanjay V, Shetty SM, Shetty RG, Managoli NA, Gugawad SC, Hitesh D. Dental health status among sensory impaired and blind institutionalized children aged 6 to 20 years. J Int Oral Health 2014;6(1):55-8. PMID:24653604

  20. 20 years of long-term atrazine monitoring in a shallow aquifer in western Germany.

    PubMed

    Vonberg, David; Vanderborght, Jan; Cremer, Nils; Pütz, Thomas; Herbst, Michael; Vereecken, Harry

    2014-03-01

    Atrazine was banned in Germany in 1991 due to findings of atrazine concentrations in ground- and drinking waters exceeding threshold values. Monitoring of atrazine concentrations in the groundwater since then provides information about the resilience of the groundwater quality to changing agricultural practices. In this study, we present results of a monitoring campaign of atrazine concentrations in the Zwischenscholle aquifer. This phreatic aquifer is exposed to intensive agricultural land use and susceptible to contaminants due to a shallow water table. In total 60 observation wells (OWs) have been monitored since 1991, of which 15 are sampled monthly today. Descriptive statistics of monitoring data were derived using the "regression on order statistics" (ROS) data censoring approach, estimating values for nondetects. The monitoring data shows that even 20 years after the ban of atrazine, the groundwater concentrations of sampled OWs remain on a level close to the threshold value of 0.1 μg l(-1) without any considerable decrease. The spatial distribution of atrazine concentrations is highly heterogeneous with OWs exhibiting permanently concentrations above the regulatory threshold on the one hand and OWs were concentrations are mostly below the limit of quantification (LOQ) on the other hand. A deethylatrazine-to-atrazine ratio (DAR) was used to distinguish between diffuse - and point-source contamination, with a global mean value of 0.84 indicating mainly diffuse contamination. Principle Component Analysis (PCA) of the monitoring dataset demonstrated relationships between the metabolite desisopropylatrazine, which was found to be exclusively associated with the parent compound simazine but not with atrazine, and between deethylatrazine, atrazine, nitrate, and the specific electrical conductivity. These parameters indicate agricultural impacts on groundwater quality. The findings presented in this study point at the difficulty to estimate mean concentrations

  1. Seroepidemiology of canine leishmaniosis in Évora (southern Portugal): 20-year trends

    PubMed Central

    2013-01-01

    Background Canine leishmaniosis (CanL) is an endemic zoonosis in the southern regions of Europe. This paper reports the trend in CanL seroprevalence in the municipality of Évora (southern Portugal), where the disease is endemic, over a period of 20 years. The work comprises three different studies that were conducted in the years of 1990 (n = 3,614), 1999 (n = 3,563) and 2010 (n = 1,485 dogs). Blood samples were collected during the anti-rabies vaccination campaigns. Anti-Leishmania antibodies were detected with the direct agglutination test (DAT). Findings The total percentages of DAT seropositive dogs were 3.9% (in 1990), 9.4% (in 1999) and 5.6% (in 2010). The overall seroprevalence was significantly higher in 1999 compared to 1990, but in 2010 a significant decrease was found in comparison with 1999. However, compared to 1990 the overall seroprevalence was still significantly higher in 2010. From 1990 to 2010 seroprevalence has switched from significantly lower to higher in the rural areas. Relatively few dogs showed clinical signs of overt disease (0.8% to 2.0%) with lymphadenopathy, onychogryphosis and skin involvement as most frequently observed. Gender associated differences in seroprevalence were not found, and most commonly seropositive dogs were working or stray animals. The mean age of seropositive dogs was significantly higher than seronegative dogs in all three sampling rounds. Conclusions A high proportion of dogs, which are apparently healthy, yet seropositive, may remain an important factor in limiting the outcome of zoonotic leishmaniosis control efforts. PMID:23587181

  2. Anterior cruciate ligament injury after more than 20 years. II. Concentric and eccentric knee muscle strength.

    PubMed

    Tengman, E; Brax Olofsson, L; Stensdotter, A K; Nilsson, K G; Häger, C K

    2014-12-01

    The long-term consequences on knee muscle strength some decades after rupture of the anterior cruciate ligament (ACL) are not established. The aims of our study were to examine peak torque more than 20 years after ACL injury and to compare their knee muscle strength to that of healthy controls. We tested 70 individuals with unilateral ACL injury 23 ± 2 years after injury, whereof 33 (21 men) were treated with physiotherapy in combination with ACL reconstruction (ACLR ) and 37 (23 men) with physiotherapy alone (ACLPT ). These were compared with 33 age- and gender-matched controls (21 men). A Kin-Com(®) dynamometer (90°/s) was used to measure peak torque in knee flexion and extension in both concentric and eccentric contractions. Knee extension peak torque, concentric and eccentric, was ∼10% lower for the injured leg compared with the non-injured leg for both ACLR (P < 0.001; P < 0.001) and ACLPT (P = 0.007; P = 0.002). The ACLPT group also showed reduced eccentric knee flexion torque of the injured leg (P = 0.008). The strength of the non-injured leg in both ACL groups was equal to that of controls. No difference was seen for those with no-or-low degree of knee osteoarthritis compared to those with moderate-to-high degree of osteoarthritis. ACL injury may lead to a persistent reduction of peak torque in the injured leg, which needs to be considered across the lifespan.

  3. Assessing the global zoo response to the amphibian crisis through 20-year trends in captive collections.

    PubMed

    Dawson, Jeff; Patel, Freisha; Griffiths, Richard A; Young, Richard P

    2016-02-01

    Global amphibian declines are one of the biggest challenges currently facing the conservation community, and captive breeding is one way to address this crisis. Using information from the International Species Information System zoo network, we examined trends in global zoo amphibian holdings across species, zoo region, and species geographical region of origin from 1994 to 2014. These trends were compared before and after the 2004 Global Amphibian Assessment to assess whether any changes occurred and whether zoo amphibian conservation effort had increased. The numbers of globally threatened species (GTS) and their proportional representation in global zoo holdings increased and this rate of increase was significantly greater after 2004. North American, European, and Oceanian GTS were best represented in zoos globally, and proportions of Oceanian GTS held increased the most since 2004. South American and Asian GTS had the lowest proportional representation in zoos. At a regional zoo level, European zoos held the lowest proportions of GTS, and this proportion did not increase after 2004. Since 1994, the number of species held in viable populations has increased, and these species are distributed among more institutions. However, as of 2014, zoos held 6.2% of globally threatened amphibians, a much smaller figure than for other vertebrate groups and one that falls considerably short of the number of species for which ex situ management may be desirable. Although the increased effort zoos have put into amphibian conservation over the past 20 years is encouraging, more focus is needed on ex situ conservation priority species. This includes building expertise and capacity in countries that hold them and tracking existing conservation efforts if the evidence-based approach to amphibian conservation planning at a global level is to be further developed. PMID:26219401

  4. Radiographic findings on 3rd molars removed in 20-year-old men.

    PubMed

    Rajasuo, Ari; Peltola, Jaakko; Ventä, Irja; Murtomaa, Heikki

    2003-10-01

    In this study we assess radiographic findings characteristic of mandibular 3rd molars that had required either routine or surgical extraction. X-ray findings relating to acute pericoronitis were also examined. The material was collected by investigating patient records and rotational panoramic radiographs of 20-year-old Finnish male conscripts (n = 738) treated during military service because of 3rd-molar-related problems. The follicle around the crown of mandibular 3rd molars with acute pericoronitis was enlarged in 19% of cases and in 13% of chronic symptom-free pericoronitis cases (not statistically significant difference). Mandibular 3rd molars extracted surgically were more often mesially inclined than those extracted routinely (61% vs. 23%; P < 0.001), partially or totally intrabony impacted (92% vs. 66%; P < 0.001) and deep situated (on average 4.2 mm vs. 2.5 mm under the occlusal plane). Surgical extraction was also associated with the roots completely developed [92% vs. 84% of the teeth routinely extracted, odds ratio (OR) 2.6, 95% confidence interval (CI) 1.2-5.5] and with the absence of radiographic pericoronitis [around 27% vs. 39% of the teeth routinely extracted (OR 0.5, 95% CI 0.3-0.8)]. In 86% of cases the space between 2nd molar and ramus of the mandible was narrower than the 3rd molar extracted surgically, whereas this was 62% in routine extraction cases (P < 0.001). We conclude that there are some typical 3rd-molar findings in rotational panoramic radiographs that show a need for surgical extraction. PMID:14763776

  5. Adenocarcinoma of unknown primary in a 20-year-old African American male.

    PubMed

    Power, Derek; Lagunes, Diane Reidy

    2009-08-01

    A 20-year-old African American male presented with a history of left flank pain and passing of light pink urine. Medical history included sickle cell trait. Urine analysis was positive for protein and blood. Metabolic profile, autoantibody screen, and complement levels were normal. Hemoglobin electrophoresis revealed an 41.8% HbS diagnostic of sickle cell trait. Creatinine clearance was normal and proteinuria was nonnephrotic. A noncontrast computed tomography (CT) scan showed left proximal hydronephrosis. Urology follow-up was arranged and the differential included renal papillary necrosis, or renal cyst rupture. He presented 3 months later with sudden onset left flank pain and gross hematuria. Serum creatinine was 1.8 mg/dL. Computed tomography scan with contrast revealed innumerable lung lesions, an enlarged heterogenously enhancing left kidney, and retroperitoneal adenopathy. Ultrasound revealed an obstructed left collecting system and a 14-cm enlarged left kidney with no discrete mass. Testicular markers/ultrasound, upper/lower endoscopies were normal. Lung biopsy revealed poorly differentiated adenocarcinoma positive for cytokeratin 7. Renal, sarcoma, and gastrointestinal markers were negative. By exclusion, it appeared that the patient had a carcinoma of unknown primary. However, with the clinical and personal history, a diagnosis of renal medullary carcinoma (RMC) was made. RMC is a rare and highly malignant tumor that should always be included in the differential of a patient with sickle cell disorder and hematuria. Renal biopsy typically fails to sample the renal medulla and radiologic findings might not raise the suspicion of a renal tumor. Thus, clinical suspicion must always be high in order to preserve the patient's only chance of prolonged survival.

  6. Cruciate Paralysis in a 20- year -old Male with an Undisplaced Type III Odontoid Fracture

    PubMed Central

    A, Mansukhani Sameer; V, Tuteja Sanesh; B, Dhar Sanjay

    2016-01-01

    Introduction: Cruciate Paralysis is a rare incomplete spinal cord syndrome presenting as brachial diplegia with minimal or no involvement of the lower extremities. It occurs as a result of trauma to the cervical spine and is associated with fractures of the axis and/or atlas. Diagnosis is confirmed on MRI and is managed by treatment of the underlying pathology. Prognosis depends on the extent of spinal cord injury and the exact cause. Case Presentation: A 20-year-old male presented to the casualty with a history of an injury to the back of the head as a result of a fall. He had severe pain in the neck and shoulder region and experienced difficulty in raising both arms and gripping objects. On examination, he had weakness of both arms, more on the right, involving the C5 to T1 distribution and brisk reflexes. There was no sensory deficit. Radiograph and a computed tomography (CT) scan of the cervical spine showed a type III undisplaced odontoid fracture. MRI showed a signal abnormality in the spinal cord at the level of the cervicomedullary junction extending up to the body of C2 vertebra. The patient was treated with traction in Gardner Wells tongs for six weeks and a sterno-occipital-mandibular immobilizer immobilizer (SOMI) brace thereafter. At three-month follow-up, he had attained complete neurological recovery. Conclusion: Cruciate Paralysis is an important cause of brachial diplegia and must be differentiated from Acute Central Cord syndrome which can have similar clinical features. PMID:27299124

  7. Correlates of heart rate recovery over 20 years in a population sample

    PubMed Central

    Carnethon, Mercedes R.; Sternfeld, Barbara; Liu, Kiang; Jacobs, David R.; Schreiner, Pamela J.; Williams, O. Dale; Lewis, Cora E.; Sidney, Stephen

    2013-01-01

    Introduction Slow heart rate recovery (HRR) from a graded exercise treadmill test (GXT) is a marker of impaired parasympathetic reactivation that is associated with elevated mortality. Our objective was to test whether demographic, behavioral or coronary heart disease (CHD) risk factors during young adulthood were associated with the development of slow HRR. Methods Participants from the Coronary Artery Risk Development in Young Adults study underwent symptom-limited maximal GXT using a modified Balke protocol at baseline (1985–86) and 20-year follow-up (2005–06) examinations. HRR was calculated as the difference between peak heart rate (HR) and HR two-minutes following cessation of the GXT. Slow HRR was defined as 2-minute HRR < 22 beats·min−1. Results In 2,730 participants who did not have slow HRR at baseline, mean HRR was 44 beats*min−1 (SD = 11) at baseline and declined to 40 beats·min−1 (SD=12) in 2005–06; slow HRR developed in 5% (n=135) of the sample by 2005–06. Female sex, black race, fewer years of education, obesity, cigarette smoking, higher depressive symptoms, higher fasting glucose, hypertension, metabolic syndrome and physical inactivity and low fitness were each associated with incident slow HRR. In a multivariable model higher BMI, larger waist, low education, fasting glucose and current smoking remained significantly associated with incident slow HRR. Increasing BMI (per SD higher) over follow-up and incident hypertension, diabetes and metabolic syndrome (in the subsets of participants who were free from those conditions at baseline), were each associated with a significantly elevated odds of incident slow HRR. Conclusions On average, HRR declines with aging; however, the odds of having slow HRR in early middle age is significantly associated with traditional CHD risk factors. PMID:21796053

  8. Oro-facial injuries in Central American and Caribbean sports games: a 20-year experience.

    PubMed

    Amy, Enrique

    2005-06-01

    Dental services in sports competitions in the Games sponsored by the International Olympic Committee are mandatory. In every Central American, Pan American and Olympic Summer Games, as well as Winter Games, the Organizing Committee has to take all the necessary measures to assure dental services to all competitors. In all Olympic villages, as part of the medical services, a dental clinic is set up to treat any dental emergency that may arise during the Games. Almost every participating country in the Games has its own medical team and some may include a dentist. The major responsibilities of the team dentist as a member of the national sports delegation include: (i) education of the sports delegation about different oral and dental diseases and the illustration of possible problems that athletes or other personnel may encounter during the Games, (ii) adequate training and management of orofacial trauma during the competition, (iii) knowledge about the rules and regulations of the specific sport that the dentist is working, (iv) understanding of the anti-doping control regulations and procedures, (v) necessary skills to fabricate a custom-made and properly fitted mouth guard to all participants in contact or collision sports of the delegation. This study illustrates the dental services and occurrence of orofacial injury at the Central American and Caribbean Sports Games of the Puerto Rican Delegation for the past 20 years. A total of 2107 participants made up the six different delegations at these Games. Of these 279 or 13.2% were seen for different dental conditions. The incidence of acute or emergency orofacial conditions was 18 cases or 6% of the total participants. The most frequent injury was lip contusion with four cases and the sport that experienced more injuries was basketball with three cases.

  9. Exact event horizon of a black hole merger

    NASA Astrophysics Data System (ADS)

    Emparan, Roberto; Martínez, Marina

    2016-08-01

    We argue that the event horizon of a binary black hole merger, in the extreme-mass-ratio limit where one of the black holes is much smaller than the other, can be described in an exact analytic way. This is done by tracing in the Schwarzschild geometry a congruence of null geodesics that approaches a null plane at infinity. Its form can be given explicitly in terms of elliptic functions, and we use it to analyze and illustrate the time-evolution of the horizon along the merger. We identify features such as the line of caustics at which light rays enter the horizon, and the critical point at which the horizons touch. We also compute several quantities that characterize these aspects of the merger.

  10. New Horizons Pluto Flyby Guest Operations

    NASA Astrophysics Data System (ADS)

    Simon, M.; Turney, D.; Fisher, S.; Carr, S. S.

    2015-12-01

    On July 14, 2015, after 9.5 years of cruise, NASA's New Horizons spacecraft flew past the Pluto system to gather first images humankind had ever seen on Pluto and its five moons. While much has been discovered about the Pluto system since New Horizons launch in 2006, the system has never been imaged at high resolution and anticipation of the "First Light" of the Pluto system had been anticipated by planetary enthusiasts for decades. The Johns Hopkins Applied Physics Laboratory (APL), which built and operates New Horizons, was the focal point for gathering three distinct groups: science and engineering team members; media and public affairs representatives; and invited public, including VIP's. Guest operations activities were focused on providing information primarily to the invited public and VIP's. High level objectives for the Guest Operations team was set to entertain and inform the general public, offer media reaction shots, and to deconflict activities for the guests from media activities wherever possible. Over 2000 people arrived at APL in the days surrounding closest approach for guest, science or media operations tracks. Reaction and coverage of the Guest Operations events was universally positive and global in impact: iconic pictures of the auditorium waving flags during the moment of closest approach were published in media outlets on every continent. Media relations activities ensured coverage in all key media publications targeted for release, such as the New York Times, Science, Le Monde, and Nature. Social and traditional media coverage of the events spanned the globe. Guest operations activities are designed to ensure that a guest has a memorable experience and leaves with a lifelong memory of the mission and their partnership in the activity. Results, lessons learned, and other data from the New Horizons guest operations activity will be presented and analyzed.

  11. Water maser variability over 20 years in a large sample of star-forming regions: the complete database

    NASA Astrophysics Data System (ADS)

    Felli, M.; Brand, J.; Cesaroni, R.; Codella, C.; Comoretto, G.; Di Franco, S.; Massi, F.; Moscadelli, L.; Nesti, R.; Olmi, L.; Palagi, F.; Panella, D.; Valdettaro, R.

    2007-12-01

    Context: Water vapor emission at 22 GHz from masers associated with star-forming regions is highly variable. Aims: We present a database of up to 20 years of monitoring of a sample of 43 masers within star-forming regions. The sample covers a large range of luminosities of the associated IRAS source and is representative of the entire population of H2O masers of this type. The database forms a good starting point for any further study of H2O maser variability. Methods: The observations were obtained with the Medicina 32-m radiotelescope, at a rate of 4-5 observations per year. Results: To provide a database that can be easily accessed through the web, we give for each source: plots of the calibrated spectra, the velocity-time-flux density plot, the light curve of the integrated flux, the lower and upper envelopes of the maser emission, the mean spectrum, and the rate of the maser occurrence as a function of velocity. Figures for just one source are given in the text for representative purposes. Figures for all the sources are given in electronic form the appendix. A discussion of the main properties of the H2O variability in our sample will be presented in a forthcoming paper. Based on observations with the Medicina radiotelescope operated by INAF - Istituto di Radioastronomia.

  12. Zonda downslope winds in the central Andes of South America in a 20-year climate simulation with the Eta model

    NASA Astrophysics Data System (ADS)

    Antico, Pablo L.; Chou, Sin Chan; Mourão, Caroline

    2015-12-01

    The Zonda wind is a local version of the alpine foehn in the central Andes Mountains in South America. It blows on the eastern slopes and produces an extremely warm and dry condition in Argentina. In this study, the occurrence of Zonda wind events during a 20-year simulation from the regional Eta model is analyzed and results are compared to previous studies of Zonda wind events based on weather observations. We define a set of parameters to account for the zonal pressure gradient across the mountain, vertical movement, and air humidity typical of Zonda wind events. These parameters are applied to characterize Zonda wind events in model run and to classify them as surface-level or high-level episodes. The resulting annual distribution of Zonda occurrences based on composite analyses shows a preference for winter and spring with rare occurrences during summer. For the surface-level Zonda wind events, the highest frequency occurs during spring. Whereas surface-level Zonda wind episodes more commonly initiate in the afternoon, high-level Zonda wind events show no preference for a given initiation time. Our results are mostly in agreement with previous observational results.

  13. Shifts in microbial biomass indicators track changes in carbon and nitrogen cycles during tree plantation development to 20 years

    NASA Astrophysics Data System (ADS)

    Munson, A. D.; Maillard, E.; Paré, D.

    2010-12-01

    In the context increasing atmospheric CO2 concentration, there is a growing interest for using afforestation and reforestation to claim emissions reductions. Establishment of plantations necessarily involves silvicultural treatments that affect environmental conditions and hence soil microbial communities, influencing carbon and nitrogen cycles and potential soil carbon sequestration. We have monitored soil microbial indicators during a twenty year period of ecosystem recovery from disturbance at the Petawawa Research Forest (Ontario, Canada), in plantations of white pine (Pinus strobus L.) and white spruce (Picea glauca). The first ten years was marked by important changes in Cmic:Corg and Cmic:Nmic, related to vegetation control that provoked modification of bacteria:fungi ratios, accelerated N cycling and loss, as well as shifts in vegetation composition that are still quite marked after twenty years. After another 10 years (at 20 yrs) we note a closing of the N cycle and again important shifts in microbial indicators. In the humus, biomass C has recovered over time, but the Cmic:Nmic is decreasing constantly from 4 to 20 years, with increases in the Nmic pool; in the surface mineral soil, this increase in the Nmic pool is even more striking. Plots treated to control vegetation are dominated by conifers versus deciduous vegetation after twenty years, provoking a higher Cmic:Nmic in the humus layer. We attempt to interpret differences in the labile carbon fraction in the humus and mineral soil at twenty years in light of these observed dynamics.

  14. Neighborhood availability of convenience stores and diet quality: findings from 20 years of follow-up in CARDIA

    PubMed Central

    Rummo, Pasquale E.; Meyer, Katie A.; Boone-Heinonen, Janne; Jacobs, David R.; Kiefe, Catarina I.; Lewis, Cora E.; Steffen, Lyn M.; Gordon-Larsen, Penny

    2015-01-01

    OBJECTIVES We examined the association between neighborhood convenience stores and diet outcomes over 20 years of the Coronary Artery Risk Development in Young Adults (CARDIA) study. METHODS We used dietary data from CARDIA exam years 1985–6, 1992–3, and 2005–6 (n=3,299) and geographically and temporally matched neighborhood-level food resource (Dun & Bradstreet) and US Census data. We used random-effects repeated measures regression to estimate associations between availability of neighborhood convenience stores with diet outcomes, and whether these associations differed by individual-level income. RESULTS In multivariable-adjusted analyses, greater availability of neighborhood convenience stores was associated with lower diet quality (mean score=66.3, SD=13.0) for participants with lower (versus higher) individual-level income (β, −2.40; 95% CI: −3.30, −1.51); associations at higher individual-level income were weaker. We observed similar associations with whole grain consumption across time, but no statistically significant associations with consumption of sugar-sweetened beverages, artificially-sweetened beverages, snacks, processed meats, fruits, or vegetables. CONCLUSIONS Convenience stores may promote lower quality diets. Furthermore, low-income individuals may be most sensitive to convenience store availability, and thus may benefit most from improvements to the food environment. PMID:25790410

  15. Sleep characteristics, chronotype and winter depression in 10-20-year-olds in northern European Russia.

    PubMed

    Borisenkov, Mikhail F; Petrova, Natalia B; Timonin, Vladimir D; Fradkova, Lyudmila I; Kolomeichuk, Sergey N; Kosova, Anna L; Kasyanova, Olga N

    2015-06-01

    The purpose of this work was to examine the relationships between geographical coordinates and the prevalence of winter depression (SADW ), and to compare the sleep characteristics and chronotype of youths with and without SADW . We conducted a cross-sectional study of self-reported sleep characteristics, chronotype and winter depression in northern European Russia. Two questionnaires, the Munich Chronotype Questionnaire (MCTQ) and the Seasonal Pattern Assessment Questionnaire (SPAQ), were administered to a total of 3435 adolescents aged 10-20 years (1517 males and 1918 females). The prevalence of SADW in the study population was 8.4% and sub-SADW 11.8%. Four variables predicted the likelihood of SADW in youths: sex [higher in females: odds ratio (OR): 1.87, P < 0.0001], age (increases with age: OR: 1.09, P < 0.001), latitude (higher in the North: OR: 1.49, P < 0.029) and position in the time zone (higher in the West: OR: 1.61, P < 0.001). Later sleeping and waking, longer sleep latencies, more severe sleep inertia, shorter total sleep times and lower sleep efficiencies were observed in both males and females with SADW . The influence of SADW on sleep characteristics was more pronounced on school days. Significant phase delays of the sleep-wake rhythm and severe social jetlag (the difference between the mid-point of sleep phase at weekends and on workdays) were observed in females with SADW , but not in males. There are significant differences in sleep characteristics and chronotype between people with SADW and no-SAD. We demonstrate that both latitude of residence and location within the time zone are significant predictors of SADW in young inhabitants of the North.

  16. 20 years of ClO measurements in the Antarctic lower stratosphere

    NASA Astrophysics Data System (ADS)

    Nedoluha, Gerald E.; Connor, Brian J.; Mooney, Thomas; Barrett, James W.; Parrish, Alan; Gomez, R. Michael; Boyd, Ian; Allen, Douglas R.; Kotkamp, Michael; Kremser, Stefanie; Deshler, Terry; Newman, Paul; Santee, Michelle L.

    2016-08-01

    We present 20 years (1996-2015) of austral springtime measurements of chlorine monoxide (ClO) over Antarctica from the Chlorine Oxide Experiment (ChlOE1) ground-based millimeter wave spectrometer at Scott Base, Antarctica, as well 12 years (2004-2015) of ClO measurements from the Aura Microwave Limb Sounder (MLS). From August onwards we observe a strong increase in lower stratospheric ClO, with a peak column amount usually occurring in early September. From mid-September onwards we observe a strong decrease in ClO. In order to study interannual differences, we focus on a 3-week period from 28 August to 17 September for each year and compare the average column ClO anomalies. These column ClO anomalies are shown to be highly correlated with the average ozone mass deficit for September and October of each year. We also show that anomalies in column ClO are strongly anti-correlated with 30 hPa temperature anomalies, both on a daily and an interannual timescale. Making use of this anti-correlation we calculate the linear dependence of the interannual variations in column ClO on interannual variations in temperature. By making use of this relationship, we can better estimate the underlying trend in the total chlorine (Cly = HCl + ClONO2 + HOCl + 2 × Cl2 + 2 × Cl2O2 + ClO + Cl). The resultant trends in Cly, which determine the long-term trend in ClO, are estimated to be -0.5 ± 0.2, -1.4 ± 0.9, and -0.6 ± 0.4 % year-1, for zonal MLS, Scott Base MLS (both 2004-2015), and ChlOE (1996-2015) respectively. These trends are within 1σ of trends in stratospheric Cly previously found at other latitudes. The decrease in ClO is consistent with the trend expected from regulations enacted under the Montreal Protocol.

  17. The Mectizan Donation Program: 20 years of successful collaboration - a retrospective.

    PubMed

    Colatrella, B

    2008-09-01

    , via community-based treatment programmes in 125,000 communities in 33 endemic countries. This 20-year-old effort has achieved a number of notable results, including positive health impacts, economic benefits, strengthened health systems, and the empowerment of communities where the delivery and administration of Mectizan are managed. The MDP serves as a model for similar health programmes in the developing world and has also laid the foundation for the current integration efforts around 'neglected' tropical diseases. It has also taught the world many valuable lessons - about how to mobilize resources to address significant health challenges - and has demonstrated that it is possible, through public-private partnerships, to deliver healthcare to long-neglected populations, despite seemingly insurmountable obstacles including inadequate financial and human resources, lack of social, economic and health infrastructures, civil unrest and political strife, and competing, high-priority health issues.

  18. DUACS DT2014: the new multi-mission altimeter data set reprocessed over 20 years

    NASA Astrophysics Data System (ADS)

    Pujol, Marie-Isabelle; Faugère, Yannice; Taburet, Guillaume; Dupuy, Stéphanie; Pelloquin, Camille; Ablain, Michael; Picot, Nicolas

    2016-09-01

    The new DUACS DT2014 reprocessed products have been available since April 2014. Numerous innovative changes have been introduced at each step of an extensively revised data processing protocol. The use of a new 20-year altimeter reference period in place of the previous 7-year reference significantly changes the sea level anomaly (SLA) patterns and thus has a strong user impact. The use of up-to-date altimeter standards and geophysical corrections, reduced smoothing of the along-track data, and refined mapping parameters, including spatial and temporal correlation-scale refinement and measurement errors, all contribute to an improved high-quality DT2014 SLA data set. Although all of the DUACS products have been upgraded, this paper focuses on the enhancements to the gridded SLA products over the global ocean. As part of this exercise, 21 years of data have been homogenized, allowing us to retrieve accurate large-scale climate signals such as global and regional MSL trends, interannual signals, and better refined mesoscale features.An extensive assessment exercise has been carried out on this data set, which allows us to establish a consolidated error budget. The errors at mesoscale are about 1.4 cm2 in low-variability areas, increase to an average of 8.9 cm2 in coastal regions, and reach nearly 32.5 cm2 in high mesoscale activity areas. The DT2014 products, compared to the previous DT2010 version, retain signals for wavelengths lower than ˜ 250 km, inducing SLA variance and mean EKE increases of, respectively, +5.1 and +15 %. Comparisons with independent measurements highlight the improved mesoscale representation within this new data set. The error reduction at the mesoscale reaches nearly 10 % of the error observed with DT2010. DT2014 also presents an improved coastal signal with a nearly 2 to 4 % mean error reduction. High-latitude areas are also more accurately represented in DT2014, with an improved consistency between spatial coverage and sea ice edge

  19. Tracking log transport and deposition during a 20-year flood in a wide mountain river

    NASA Astrophysics Data System (ADS)

    Wyżga, Bartłomiej; Mikuś, Paweł; Zawiejska, Joanna; Ruiz-Villanueva, Virginia; Kaczka, Ryszard; Czech, Wiktoria

    2016-04-01

    Distance of large wood transport during floods and conditions for wood deposition in wide mountain rivers are still insufficiently recognised. Tracking logs tagged with radio transmitters was used to investigate differences in depositional conditions and the length of log displacement during a 20-year flood between channel reaches of different morphology in the Czarny Dunajec River, Polish Carpathians. During a rising limb of the flood, logs were placed into the river at the beginning of an incised reach, close to the beginning of a channelized reach, and 1 km upstream from the beginning of a wide, multi-thread reach. The incised, channelized, and multi-thread reaches retained 12.5%, 33%, and 94% of tagged logs introduced to these reaches, and all the logs retained in the multi-thread reach were deposited in its upstream half. Significant differences in the length of displacement existed between the logs delivered to the river at the three locations, with logs placed into the river at the beginning of the incised reach moved the longest distances and those delivered just upstream from the multi-thread reach the shortest ones. One-fourth of the logs were deposited in a low-flow channel or on channel margin, one-fifth on the floodplain and more than half on gravel bars. After the flood, river cross-sections with deposited logs and a set of cross-sections without wood deposits were surveyed to collect data for one-dimensional modelling of hydraulic conditions at the flood peak. The cross-sections with deposited logs were typified by significantly greater flow width and flow area, and significantly smaller mean flow depth, mean velocity, Froude number, mean bed shear stress and unit stream power. Principal component analysis of the hydraulic parameters in the analysed cross-sections grouped the two types of cross-sections in distinct clusters, indicating that multi-thread cross-sections differed in hydraulic parameters from all the other cross-sections. The experiment

  20. The Mectizan Donation Program: 20 years of successful collaboration - a retrospective.

    PubMed

    Colatrella, B

    2008-09-01

    , via community-based treatment programmes in 125,000 communities in 33 endemic countries. This 20-year-old effort has achieved a number of notable results, including positive health impacts, economic benefits, strengthened health systems, and the empowerment of communities where the delivery and administration of Mectizan are managed. The MDP serves as a model for similar health programmes in the developing world and has also laid the foundation for the current integration efforts around 'neglected' tropical diseases. It has also taught the world many valuable lessons - about how to mobilize resources to address significant health challenges - and has demonstrated that it is possible, through public-private partnerships, to deliver healthcare to long-neglected populations, despite seemingly insurmountable obstacles including inadequate financial and human resources, lack of social, economic and health infrastructures, civil unrest and political strife, and competing, high-priority health issues. PMID:18718147

  1. 20-Years of Population-Based Cancer Registration in Hepatitis B and Liver Cancer Prevention in The Gambia, West Africa

    PubMed Central

    Bah, Ebrima; Carrieri, Maria Patrizia; Hainaut, Pierre; Bah, Yusupha; Nyan, Ousman; Taal, Makie

    2013-01-01

    Background The Gambia Hepatitis Intervention Study (GHIS) was designed as a randomised control trial of infant hepatitis B vaccination applied to public health policy, with the main goal of preventing primary liver cancer later in adult life in The Gambia. To that effect, the National Cancer Registry of The Gambia (NCR), a population-based cancer registry (PBCR), was established in 1986 to actively collect data on all cancer diagnosis nation-wide. We extracted 20-years (1990-2009) of data to assess for the first time, the evolution of the most common cancers, also describe and demonstrate the role of the PBCR in a hepatitis B and liver cancer prevention programme in this population. Methods and Findings We estimated Age-Standardised Incidence Rates (ASR (W)) of the most common cancers registered during the period by gender. The registration period was divided into four 5-year intervals and incidence rates were estimated for each interval. The most common cancers in males were liver, prostate, lung plus bronchus, non-Hodgkin lymphoma (NHL) and stomach, accounting for 60%, 5%, 4%, 5% and 3%, respectively. Similarly, cancers of the cervix uteri, liver, breast and NHL, were the most common in females, accounting for 33%, 24%, 11% and 4% of the female cancers, respectively. Conclusions Cancer incidence has remained relatively stable over time, but as shown elsewhere in sub-Saharan Africa the disease is a threat in The Gambia. The infection related cancers which are mostly preventable (HBV in men and HPV/HIV in women) were the most common. At the moment the data is not enough to detect an effect of hepatitis B vaccination on liver cancer incidence in The Gambia. However, we observed that monitoring case occurrence through PBCR is a key public health pre-requisite for rational planning and implementation of targeted interventions for improving the health of the population. PMID:24098724

  2. Common Ground: Expanding Our Horizons.

    ERIC Educational Resources Information Center

    McDevitt, Michele J.

    In "Common Ground: Dialogue, Understanding, and the Teaching of Composition," Kurt Spellmeyer seeks to familiarize students and teachers with the linguistic and cultural no-man's-land separating them. Reinstating the value of two writing conventions often used by traditional students--expressive and commonplaces--can help expand on the horizons of…

  3. NIF featured on BBC "Horizon"

    ScienceCinema

    Brian Cox

    2016-07-12

    The National Ignition Facility, the world's largest laser system, located at Lawrence Livermore National Laboratory, was featured in the BBC broadcast "Horizon" hosted by physicist Brian Cox. Here is the NIF portion of the program, which was entitled "Can We Make A Star On Earth?" This video is used with the express permission of the BBC.

  4. New Horizons Mission to Pluto

    NASA Technical Reports Server (NTRS)

    Delgado, Luis G.

    2011-01-01

    This slide presentation reviews the trajectory that will take the New Horizons Mission to Pluto. Included are photographs of the spacecraft, the launch vehicle, the assembled vehicle as it is being moved to the launch pad and the launch. Also shown are diagrams of the assembled parts with identifying part names.

  5. New Horizons in Education, 2000.

    ERIC Educational Resources Information Center

    Ho, Kwok Keung, Ed.

    2000-01-01

    This document contains the May and November 2000 issues of "New Horizons in Education," with articles in English and Chinese. The May issue includes the following articles: "A Key to Successful Environmental Education: Teacher Trainees' Attitude, Behaviour, and Knowledge" (Kevin Chung Wai Lui, Eric Po Keung Tsang, Sing Lai Chan); "Critical…

  6. NIF featured on BBC "Horizon"

    SciTech Connect

    Brian Cox

    2010-01-12

    The National Ignition Facility, the world's largest laser system, located at Lawrence Livermore National Laboratory, was featured in the BBC broadcast "Horizon" hosted by physicist Brian Cox. Here is the NIF portion of the program, which was entitled "Can We Make A Star On Earth?" This video is used with the express permission of the BBC.

  7. Future Economics of Liver Transplantation: A 20-Year Cost Modeling Forecast and the Prospect of Bioengineering Autologous Liver Grafts.

    PubMed

    Habka, Dany; Mann, David; Landes, Ronald; Soto-Gutierrez, Alejandro

    2015-01-01

    During the past 20 years liver transplantation has become the definitive treatment for most severe types of liver failure and hepatocellular carcinoma, in both children and adults. In the U.S., roughly 16,000 individuals are on the liver transplant waiting list. Only 38% of them will receive a transplant due to the organ shortage. This paper explores another option: bioengineering an autologous liver graft. We developed a 20-year model projecting future demand for liver transplants, along with costs based on current technology. We compared these cost projections against projected costs to bioengineer autologous liver grafts. The model was divided into: 1) the epidemiology model forecasting the number of wait-listed patients, operated patients and postoperative patients; and 2) the treatment model forecasting costs (pre-transplant-related costs; transplant (admission)-related costs; and 10-year post-transplant-related costs) during the simulation period. The patient population was categorized using the Model for End-Stage Liver Disease score. The number of patients on the waiting list was projected to increase 23% over 20 years while the weighted average treatment costs in the pre-liver transplantation phase were forecast to increase 83% in Year 20. Projected demand for livers will increase 10% in 10 years and 23% in 20 years. Total costs of liver transplantation are forecast to increase 33% in 10 years and 81% in 20 years. By comparison, the projected cost to bioengineer autologous liver grafts is $9.7M based on current catalog prices for iPS-derived liver cells. The model projects a persistent increase in need and cost of donor livers over the next 20 years that's constrained by a limited supply of donor livers. The number of patients who die while on the waiting list will reflect this ever-growing disparity. Currently, bioengineering autologous liver grafts is cost prohibitive. However, costs will decline rapidly with the introduction of new manufacturing

  8. Methane Seepage From the Arctic Shelf; 20 Years of Research on the Beaufort Sea Margin

    NASA Astrophysics Data System (ADS)

    Lorenson, T. D.; Paull, C. K.; Collett, T. S.; Dallimore, S. R.

    2008-12-01

    The U. S. Geological Survey has lead or played major roles in several efforts over the past 20 years to find geochemical evidence for gas hydrate dissociation on the Beaufort Sea shelf, a region of complex and varied geologic features that include: 1) several river deltas entering the Arctic Ocean, the largest of which is the Mackenzie River, 2) submerged continental shelf underlain by permafrost, 3) known petroleum systems of northern Alaska and the Mackenzie River Delta - Canada, 4), submerged pingo-like features (PLF's ) and, 5) pockmark fields. The results of these studies show that gas hydrate is present and that methane source can be both microbial and thermogenic. In light of our rapidly changing climate, the instability and potential methane release from Arctic gas hydrate deposits are reemerging as pivotal uncertainties. On the Alaskan Beaufort Shelf in water depths or about 10 m or less, methane concentrations in seawater are elevated relative to atmosphere. This methane likely originates from microbial degradation of organic matter deposited by rivers or coastal currents, and may be associated with organics in destabilized from recently thawed submerged shelf permafrost. In deeper water, north and west of the Prudhoe Bay area, some exceptionally high bottom water methane concentrations were measured with carbon isotopic signatures very similar (about -46 to -48‰) to gas hydrate sampled from the Mount Elbert 01 gas hydrate test well drilled in 2007 in the same area. This methane is presumably associated with the Prudhoe Bay gas hydrate and petroleum system, and likely from either gas hydrate dissociation or simple gas migration. Gas venting in and around the Mackenzie River delta is associated with offshore Pingo-like features (PLF's) and pockmarks. These PLF's resemble onshore pingos, but with an unknown origin. The region is underlain by an active petroleum system, submerged shelf permaforst, and gas hydrate. Methane concentrations are elevated in

  9. A 20-Year Review of 75 Cases of Salivary Duct Carcinoma

    PubMed Central

    Gilbert, Mark R.; Sharma, Arun; Schmitt, Nicole C.; Johnson, Jonas T.; Ferris, Robert L.; Duvvuri, Umamaheswar; Kim, Seungwon

    2016-01-01

    IMPORTANCE Salivary duct carcinoma is a rare, aggressive malignancy of the salivary glands. Owing to its rare nature, clinical data are limited, and only a few clinical studies comprise more than 50 patients. OBJECTIVE To review the University of Pittsburgh Medical Center’s experience with salivary duct carcinoma over a 20-year period, focusing on demographics, presentation, treatment, and outcome. DESIGN, SETTING, AND PARTICIPANTS This investigation was a retrospective cohort study in a multihospital institution with tertiary referral. A pathology database was reviewed for all cases of histopathologically diagnosed salivary duct carcinoma from January 1, 1995, to October 20, 2014. Patients who were referrals for pathology review only and were never seen at the institution were excluded. In total, 75 study patients were identified. The electronic medical record was reviewed for details regarding demographics, presentation, treatment, and outcome, including overall survival (OS) and disease-free survival (DFS). This study was supplemented with a review of the institution’s Head and Neck Oncology Database for further clinical details. MAIN OUTCOMES AND MEASURES Primary outcome measures consisted of OS and DFS. RESULTS The study sample comprised 75 participants with a mean age at diagnosis of 66.0 years (age range, 33–93 years), and 29% (n = 22) were female. Most primary tumors were from the parotid gland (83%), with the next most frequent site being the submandibular gland (12%). Overall, 41% of the cases were carcinoma ex pleomorphic adenoma. Rates of other histologic features included the following: perineural invasion (69%), extracapsular spread (58%), ERBB2 (formerly HER2) positivity (31%) (62% of those who were tested), and vascular invasion (61%). The median OS was 3.1 years, and the median DFS was 2.7 years. Univariate Kaplan-Meier survival analyses demonstrated that facial nerve sacrifice and extracapsular spread were associated with lower OS (2.38 vs 5

  10. 20 years of surface ozone measurements at El Tololo, Chile (2200 m asl)

    NASA Astrophysics Data System (ADS)

    Gérard Anet, Julien; Steinbacher, Martin; Emmenegger, Lukas; Buchmann, Brigitte

    2016-04-01

    Globally consistent in situ-observations of high precision and known quality are one key element in understanding global climate change and effects of human activity on the Earth's atmosphere. The spatial coverage of available data strongly depends on the species of interest and varies highly around the globe. In case of surface ozone (O3), the observational network is particularly sparse in Africa, Asia, and South America. The southern hemispheric pristine GAW-regional station "El Tololo", located in the foothills of the Chilean Andes (30.17° S, 70.80° W, 2220 m asl), has been equipped with an ozone photometer in 1995 and has since then been measuring tropospheric ozone permanently. However, these measurements were neither entirely systematically processed nor quality-controlled until recently. This situation was drastically improved in 2015 the framework of the Capacity Building and Twinning for Climate Observing Systems (CATCOS) project (www.meteoswiss.ch/catcos). Empa, in coordination with the local operator, Dirección Meteorológica de Chile (DMC), and the University of Santiago, revised the entire surface ozone measurements. The unique 20-year-long ozone data-set has been made publicly available on the World Data Centre for Greenhouse Gases (WDCGG, Japan) in mid-2015 and represents an exceptional piece of information on the southern hemispheric surface ozone distribution. In contrary to northern hemispheric stations, the positive trend in the measurements of tropospheric ozone at "El Tololo" did not level off in the recent past. More specifically, "El Tololo" shows a steady positive trend of 0.7 ppb/decade in agreement with other stations on the Southern hemisphere. However, the seasonal cycle differs strongly in behaviour, as maximum values in ozone do not peak in austral winter, but in austral spring - most probably due to stratospheric influence. We also find that the spring maximum has a retrograding tendency of around 5 days per decade. A combined

  11. Optimal investment horizons for stocks and markets

    NASA Astrophysics Data System (ADS)

    Johansen, A.; Simonsen, I.; Jensen, M. H.

    2006-10-01

    The inverse statistics is the distribution of waiting times needed to achieve a predefined level of return obtained from (detrended) historic asset prices [I. Simonsen, M.H. Jensen, A. Johansen, Eur. Phys. J. 27 (2002) 583; M.H. Jensen, A. Johansen, I. Simonsen, Physica A 234 (2003) 338]. Such a distribution typically goes through a maximum at a time coined the optimal investment horizon, τρ*, which defines the most likely waiting time for obtaining a given return ρ. By considering equal positive and negative levels of return, we reported in [M.H. Jensen, A. Johansen, I. Simonsen, Physica A 234 (2003) 338] on a quantitative gain/loss asymmetry most pronounced for short horizons. In the present paper, the inverse statistics for {2}/{3} of the individual stocks presently in the DJIA is investigated. We show that this gain/loss asymmetry established for the DJIA surprisingly is not present in the time series of the individual stocks nor their average. This observation points towards some kind of collective movement of the stocks of the index (synchronization).

  12. Art, the Urban Skyscraper, and Horizon Astronomy

    NASA Astrophysics Data System (ADS)

    Mooney, J. D.

    2016-01-01

    This presentation delineates the historiography and the iconography of my urban public sculptures which use skyscrapers as today's standing stones, markers for horizon astronomy. From 1977 to the present time, my work has engaged the public to “look up and see.” Through ephemeral works in the sky and over the water to large-scale rooftop sculptures in Los Angeles, Chicago, Atlanta, and Europe, viewers are oriented to the Milky Way, the summer triangle, and other celestial phenomena. This new urban scale art, transformative in context and gesture, has become part of the new cultural landscape.

  13. Generic isolated horizons and their applications

    PubMed

    Ashtekar; Beetle; Dreyer; Fairhurst; Krishnan; Lewandowski; Wisniewski

    2000-10-23

    The notion of isolated horizons is extended to allow for distortion and rotation. Space-times containing a black hole, itself in equilibrium but possibly surrounded by radiation, satisfy these conditions. The framework has three types of applications: (i) it provides new tools to extract physics from strong field geometry; (ii) it leads to a generalization of the zeroth and first laws of black hole mechanics and sheds new light on the "origin" of the first law; and (iii) it serves as a point of departure for black hole entropy calculations in nonperturbative quantum gravity. PMID:11030951

  14. Characterizing Methane Emissions at Local Scales with a 20 Year Total Hydrocarbon Time Series, Imaging Spectrometry, and Web Facilitated Analysis

    NASA Astrophysics Data System (ADS)

    Bradley, Eliza Swan

    Methane is an important greenhouse gas for which uncertainty in local emission strengths necessitates improved source characterizations. Although CH4 plume mapping did not motivate the NASA Airborne Visible InfraRed Imaging Spectrometer (AVIRIS) design and municipal air quality monitoring stations were not intended for studying marine geological seepage, these assets have capabilities that can make them viable for studying concentrated (high flux, highly heterogeneous) CH4 sources, such as the Coal Oil Point (COP) seep field (˜0.015 Tg CH4 yr-1) offshore Santa Barbara, California. Hourly total hydrocarbon (THC) data, spanning 1990 to 2008 from an air pollution station located near COP, were analyzed and showed geologic CH4 emissions as the dominant local source. A band ratio approach was developed and applied to high glint AVIRIS data over COP, resulting in local-scale mapping of natural atmospheric CH4 plumes. A Cluster-Tuned Matched Filter (CTMF) technique was applied to Gulf of Mexico AVIRIS data to detect CH4 venting from offshore platforms. Review of 744 platform-centered CTMF subsets was facilitated through a flexible PHP-based web portal. This dissertation demonstrates the value of investigating municipal air quality data and imaging spectrometry for gathering insight into concentrated methane source emissions and highlights how flexible web-based solutions can help facilitate remote sensing research.

  15. Patterns of Change in Terrestrial Emittance for Yellowstone National Park Using a 20-year Time Series of Landsat Thermal Data

    NASA Astrophysics Data System (ADS)

    Lawrence, R. L.; Savage, S.; Custer, S. G.; Jewett, J.; Powell, S. L.; Shaw, J. A.

    2011-12-01

    Yellowstone National Park (YNP) contains the world's largest concentration of geothermal features and is legally mandated to protect and monitor these natural features. Remote sensing is a component of the current geothermal monitoring plan. Landsat satellite data have a substantial historical archive and will continue to be collected into the future, making it the only available thermal imagery for historical analysis and long-term monitoring of geothermal areas in the entirety of YNP. Landsat imagery from Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) sensors was used to examine change trajectories for terrestrial emittance (an estimate of all heat emitted from the ground, based on relatively narrow band observations) among spatial groupings from 1986 to 2007. The trajectories were normalized by the mean terrestrial emittance for each date to account for year-to-year ambient temperature differences. Trajectories of locations with known change events at Narrow Gauge in the Mammoth Area, Minerva Terraces in the Mammoth Area, Porkchop Geyser in Gibbon Canyon, and Jewel Geyser in the Firehole River Drainage were also examined. Relationships between the spatial groupings and several change vectors (distance to geologic faults, distance to large water bodies, and distance to earthquake swarms) were explored. The analysis showed the strongest relationship between absolute difference in terrestrial emittance and earthquake swarms, with 34% of the variation explained. Certain known change events were reflected in the change trajectories, while the Landsat imagery was not able to detect other known events. This suggests that Landsat imagery might be a useful tool for monitoring geothermal responses in YNP, but cannot be expected to suffice as the sole monitoring tool.

  16. Moderate progress for ovarian cancer in the last 20 years: prolongation of survival, but no improvement in the cure rate.

    PubMed

    Engel, J; Eckel, R; Schubert-Fritschle, G; Kerr, J; Kuhn, W; Diebold, J; Kimmig, R; Rehbock, J; Hölzel, D

    2002-12-01

    Although ovarian cancer treatment has advanced in the last 20 years, long-term survival remains stable. The purpose of this study was to determine whether survival has improved in line with treatment advances in a population-based prospective cohort of ovarian cancer patients (1978-1997, with a follow-up through to 2000). The 10-year overall survival rate for cancer patients was similar before and after 1988: 32.2% (n=1661) and 34.4% (n=2089). For patients after 1988, a 12-month prolongation of median survival was observed. In terms of stage according to the International Federation of Gynecology and Obstetrics (FIGO), only FIGO I and FIGO II patients showed, in addition to a prolongation in survival, an absolute improvement of 12.9 and 12.6% after 5 years and of 13.2 and 8.6% after 10 years. This hardly affected the survival of the total sample. For the most frequent stage FIGO III patients and for FIGO IV patients, a prolongation in survival time, but no improvement in survival rate, was seen after five or 10 years. The progress in FIGO I and II patients may be due to more accurate staging. More effective chemotherapy may also explain some of the improvement. The prolongation in FIGO-stages III-IV may be due to more radical surgery. Patient selection criteria, not only the treatment modalities, may be responsible for the superior results reported in clinical trials. Cancer registries are important for evaluating the quality of healthcare delivery.

  17. 20 Years of Developing Capacity for Action-Oriented Collaborative Regional Research in the Asia-Pacific Region

    NASA Astrophysics Data System (ADS)

    Tupas, L. M.; Stevenson, L. A.

    2015-12-01

    During its 3rd strategic phase, which ran from 2010 to 2015, the APN provided support for 123 projects through its competitive collaborative regional research and capacity development programmes. With over 250 peer-reviewed papers and the underlying philosophy that the regional research it undertakes engages at least two developing countries, the 3rd strategic phase is not only improving the research capabilities of nations in the region, but is engaging the developing country community in underpinning policy-relevant research. The extent to which science is contributing to policy is further evident in that 69% of the activities conducted had some form of science-policy mechanism built in to the project activities. The period of the 3rd Strategic Phase has been witness to significant changes in the make-up of the "conventional" global change arena, with the transition of some global change programmes into the new "Future Earth" initiative. At the same time, major events such as the Rio+20 Summit, the post-2015 Sustainable Development Goals, the establishment of an IPCC-related platform for biodiversity, i.e. IPBES, and the evolving engagement of science and policy communities has kept the APN busy at what it does best - networking and partnering with the international community. The APN has embraced these changes through its dynamism, allowing the APN to meet not only the needs of the scientists and decision makers its serves in the region but those of the international science communities as well. The challenge for the APN in its next two decades will be to ensure alignment with the transforming global change arena. With key phrases such as "policy-relevant science" and "science-policy interactions" being adopted broadly by the community at large these days, the APN's niche in the global community has received considerable recognition, particularly as other institutions strive to adopt similar practices that the APN has built over the last 20 years.

  18. The sensory-motor theory of rhythm and beat induction 20 years on: a new synthesis and future perspectives

    PubMed Central

    Todd, Neil P. M.; Lee, Christopher S.

    2015-01-01

    Some 20 years ago Todd and colleagues proposed that rhythm perception is mediated by the conjunction of a sensory representation of the auditory input and a motor representation of the body (Todd, 1994a, 1995), and that a sense of motion from sound is mediated by the vestibular system (Todd, 1992a, 1993b). These ideas were developed into a sensory-motor theory of rhythm and beat induction (Todd et al., 1999). A neurological substrate was proposed which might form the biological basis of the theory (Todd et al., 2002). The theory was implemented as a computational model and a number of experiments conducted to test it. In the following time there have been several key developments. One is the demonstration that the vestibular system is primal to rhythm perception, and in related work several experiments have provided further evidence that rhythm perception is body dependent. Another is independent advances in imaging, which have revealed the brain areas associated with both vestibular processing and rhythm perception. A third is the finding that vestibular receptors contribute to auditory evoked potentials (Todd et al., 2014a,b). These behavioral and neurobiological developments demand a theoretical overview which could provide a new synthesis over the domain of rhythm perception. In this paper we suggest four propositions as the basis for such a synthesis. (1) Rhythm perception is a form of vestibular perception; (2) Rhythm perception evokes both external and internal guidance of somatotopic representations; (3) A link from the limbic system to the internal guidance pathway mediates the “dance habit”; (4) The vestibular reward mechanism is innate. The new synthesis provides an explanation for a number of phenomena not often considered by rhythm researchers. We discuss these along with possible computational implementations and alternative models and propose a number of new directions for future research. PMID:26379522

  19. The Malcolm horizon: History and future

    NASA Technical Reports Server (NTRS)

    Malcolm, R.

    1984-01-01

    The development of the Malcolm Horizon, a peripheral vision horizon used in flight simulation, is discussed. A history of the horizon display is presented as well as a brief overview of vision physiology, and the role balance plays is spatial orientation. Avenues of continued research in subconscious cockpit instrumentation are examined.

  20. A Look Back at Assembly and Test of the New Horizons Radioisotope Power System

    NASA Astrophysics Data System (ADS)

    Harmon, B. Alan; Bohne, William A.

    2007-01-01

    The New Horizons mission to Pluto (PNH) was launched on January 19, 2006, from the Kennedy Space Center with one General Purpose Heat Source-Radioisotope Thermoelectric Generator (GPHS-RTG) providing electrical and thermal power for the spacecraft. The spacecraft is scheduled to swing by Jupiter in February 2007 on a gravity assist trajectory, and is expected to reach the Pluto-Charon system by July 2015. As of beginning of space vacuum operation, the GPHS-RTG was providing close to 246 watts of electrical power and should be near 200 watts at close approach to Pluto. The GPHS-RTG for PNH is of essentially the same design as was used successfully on the Galileo, Ulysses and Cassini missions; however, time, resource, and environmental constraints imparted some unique aspects to the development program. The unavailability of a full complement of fresh plutonium oxide fuel, in particular, made it necessary to recover older inventory fuel from a 20-year old un-flown GPHS-RTG that had served as a backup unit for prior GPHS-RTG missions. The combination of fresh and older fuel for the PNH GPHS-RTG required special test and assembly activities, with the knowledge that the unit would be operating under somewhat off-nominal conditions than its predecessors. We highlight some of these assembly and test differences from the ``in family'' processing and performance of the previous GPHS-RTGs.

  1. On tunneling across horizons

    NASA Astrophysics Data System (ADS)

    Vanzo, L.

    2011-07-01

    The tunneling method for stationary black holes in the Hamilton-Jacobi variant is reconsidered in the light of some critiques that have been moved against. It is shown that once the tunneling trajectories have been correctly identified the method is free from internal inconsistencies, it is manifestly covariant, it allows for the extension to spinning particles and it can even be used without solving the Hamilton-Jacobi equation. These conclusions borrow support on a simple analytic continuation of the classical action of a pointlike particle, made possible by the unique assumption that it should be analytic in the complexified Schwarzschild or Kerr-Newman space-time. A more general version of the Parikh-Wilczek method will also be proposed along these lines.

  2. Enzyme exposure, smoking and lung function in employees in the detergent industry over 20 years. Medical Subcommittee of the UK Soap and Detergent Industry Association.

    PubMed

    Cathcart, M; Nicholson, P; Roberts, D; Bazley, M; Juniper, C; Murray, P; Randell, M

    1997-11-01

    This study was undertaken to examine the long term relationship between lung function, smoking and exposure to enzymes in the detergent industry. A total of 731 male workers from five locations in the United Kingdom were subject to respiratory health surveillance including lung function testing over a period of 4-20 years. Exposure groups were defined by job history. Significantly different rates of fall in FEV1 and FVC with time were found by geographical location and by smoking habit, but there were no consistent trends with enzyme exposure.

  3. Take a Bite Out of Crime: Get Ready To Celebrate 20 Years. Crime Prevention Month Action Kit.

    ERIC Educational Resources Information Center

    National Crime Prevention Council, Washington, DC.

    This Crime Prevention Month kit is designed to help plan crime prevention month activities for 1999 and into 2000, the year the Take a Bite Out of Crime character, McGruff the Crime Dog, celebrates 20 years of existence. This 15-month planning calendar provides long-term strategies for preventing crime in the community, which can be carried out…

  4. Back to the Future: Help! It Was 20 Years Ago, and We've Only Just Arrived!

    ERIC Educational Resources Information Center

    Coffield, Kate

    This paper traces an educator's experiences with computers over a span of 20 years, and describes the computerization of and concomitant obstacles faced by the Humanities department at the American University in Cairo, Egypt (AUC). The computerization of AUC began in the 1980s, with workstations mainly in the science, math, engineering, and…

  5. Average and Bright Adults with Parents with Mild Cognitive Difficulties: The Huck Finn Syndrome 20 Years Later

    ERIC Educational Resources Information Center

    O'Neill, Audrey Myerson

    2011-01-01

    Background: This longitudinal study of 20 average and bright adults with parents with cognitive difficulties follows a study 20 years earlier of their childhood adaptation to their parents. Method: Semistructured interviews about life situation and changes and perception of family-of-origin. Results: The participants' socioeconomic status changed…

  6. Cattell-Horn-Carroll Cognitive-Achievement Relations: What We Have Learned from the Past 20 Years of Research

    ERIC Educational Resources Information Center

    McGrew, Kevin S.; Wendling, Barbara J.

    2010-01-01

    Contemporary Cattell-Horn-Carroll (CHC) theory of cognitive abilities has evolved over the past 20 years and serves as the theoretical foundation for a number of current cognitive ability assessments. CHC theory provides a means by which we can better understand the relationships between cognitive abilities and academic achievement, an important…

  7. Problem-Solving Appraisal and Human Adjustment: A Review of 20 Years of Research Using the Problem Solving Inventory

    ERIC Educational Resources Information Center

    Heppner, P. Paul; Witty, Thomas E.; Dixon, Wayne A.

    2004-01-01

    This article reviews and synthesizes more than 120 studies from 20 years (1982-2002) of research that has examined problem-solving appraisal as measured by the Problem Solving Inventory (PSI). The goals of the article are fourfold: (a) introduce the construct of problem-solving appraisal and the PSI within the applied problem-solving literature,…

  8. What has happened in about the last 20 years in the Canyoles watershed?

    NASA Astrophysics Data System (ADS)

    Ángel González Peñaloza, Félix; Cerdà, Artemi; Díaz del Olmo, Fernando

    2013-04-01

    Along history, the Mediterranean arid lands have undergone widespread land use transformation, especially in recent decades (Piqueras, 2012). There are changes driven by socio-economic conditions, such as European Agricultural Policies (MacDonald et al., 2000; Keenleyside and Tucker, 2010; Renwick et al., 2013), which have caused land degradation processes (soil erosion, soil sealing, water pollution, salinization, wildfires, land abandonment, urban sprawl and intensive agricultural practices). Land degradation is the results of a complex Socio Ecological System (SES) which should be addressed using the Geographical Information System (GIS) to identify and assess the spatial variation of land use change. Therefore, the aim of this work has been to describe and assess the land use change by human activities in a typical Mediterranean watershed (Cànyoles Valley) located at South-East of Iberian Peninsula as a part of the Land Ecosystem and Degradation Desertification Response Assessment (LEDDRA) project, which has undergone a quick land use change in last two decades (1986 - 2005). Results reveal that the surface area devoted to rainfed crops (e.g., olive crops (47 %) and vineyards (28 %) and forestry have decline significantly; while the citrus orchards (irrigated crops) and unproductive areas (e.g., roads and railways, urban areas) have been increasing its surface in just about last 20 years in 45 % and 67 %, respectively. According to the literature review (Cerdà, 1994; Cerdá et al., 1999, 2007; Cerdà, 2007; Bodí et al., 2012; González-Peñaloza, 2012) these recent changes, in the study site, have caused many environmental disturbances mainly due to the lack control strategies plans of land degradation. Acknowledgements This research is being conducted by the EU project "Land Ecosystem and Degradation Desertification: Assessing the Fit of Responses" LEDDRA 243857 CONSORTIUM AGREEMENT. TR07 - VII PROGRAMA MARCO - ENERGÍA FP7-ENERGY-2007-2-TREN. - European

  9. Geometric properties of static Einstein-Maxwell dilaton horizons with a Liouville potential

    SciTech Connect

    Abdolrahimi, Shohreh; Shoom, Andrey A.

    2011-05-15

    We study nondegenerate and degenerate (extremal) Killing horizons of arbitrary geometry and topology within the Einstein-Maxwell-dilaton model with a Liouville potential (the EMdL model) in d-dimensional (d{>=}4) static space-times. Using Israel's description of a static space-time, we construct the EMdL equations and the space-time curvature invariants: the Ricci scalar, the square of the Ricci tensor, and the Kretschmann scalar. Assuming that space-time metric functions and the model fields are real analytic functions in the vicinity of a space-time horizon, we study the behavior of the space-time metric and the fields near the horizon and derive relations between the space-time curvature invariants calculated on the horizon and geometric invariants of the horizon surface. The derived relations generalize similar relations known for horizons of static four- and five-dimensional vacuum and four-dimensional electrovacuum space-times. Our analysis shows that all the extremal horizon surfaces are Einstein spaces. We present the necessary conditions for the existence of static extremal horizons within the EMdL model.

  10. Black holes or firewalls: A theory of horizons

    NASA Astrophysics Data System (ADS)

    Nomura, Yasunori; Varela, Jaime; Weinberg, Sean J.

    2013-10-01

    We present a quantum theory of black hole (and other) horizons, in which the standard assumptions of complementarity are preserved without contradicting information theoretic considerations. After the scrambling time, the quantum mechanical structure of a black hole becomes that of an eternal black hole at the microscopic level. In particular, the stretched horizon degrees of freedom and the states entangled with them can be mapped into the near-horizon modes in the two exterior regions of an eternal black hole, whose mass is taken to be that of the evolving black hole at each moment. Salient features arising from this picture include (i) the number of degrees of freedom needed to describe a black hole is eA/2lP2, where A is the area of the horizon; (ii) black hole states having smooth horizons, however, span only an eA/4lP2-dimensional subspace of the relevant eA/2lP2-dimensional Hilbert space; (iii) internal dynamics of the horizon is such that an infalling observer finds a smooth horizon with a probability of 1 if a state stays in this subspace. We identify the structure of local operators responsible for describing semiclassical physics in the exterior and interior spacetime regions and show that this structure avoids the arguments for firewalls—the horizon can keep being smooth throughout the evolution. We discuss the fate of infalling observers under various circumstances, especially when the observers manipulate degrees of freedom before entering the horizon, and we find that an observer can never see a firewall by making a measurement on early Hawking radiation. We also consider the presented framework from the viewpoint of an infalling reference frame and argue that Minkowski-like vacua are not unique. In particular, the number of true Minkowski vacua is infinite, although the label discriminating these vacua cannot be accessed in usual nongravitational quantum field theory. An application of the framework to de Sitter horizons is also discussed.

  11. Effective hydraulic properties on a highly heterogeneous soil horizon

    NASA Astrophysics Data System (ADS)

    Samouëlian, A.; Cousin, I.; Frison, A.; Richard, G.

    2009-04-01

    Knowing the soil hydraulic functioning for agricultural practices is more and more important in the context of global change. In that context, soil horizons represent the reference soil volume in term of soil functioning. Nevertheless they can be heterogeneous as for example, stony horizons, cultivated horizons, or also specific weathering horizons like those in Albeluvisol. The determination of effective hydraulic properties in these heterogeneous horizons can not be done by classical laboratory experiments like Multi-Step-Outflow or evaporative Wind experiment. So it remains a real challenge to get the effective hydraulic properties. The aim of this paper is to propose a methodology for the determination of effective hydraulic properties of heterogeneous soil horizons based on the knowledge of the: on one hand the 3D soil structure and on the other hand the local hydraulic properties. The studied soil is an Albeluvisol that exhibits some horizons composed by the juxtaposition of two Elementary Pedological Volumes (EPVs); they can be visually distinguished by their colours (ochre and white) and they have differential hydraulic functioning: the clayey ochre ones conduct less water than the loamy white ones. Local hydraulic properties were determined on each type of volumes. The 3D structure of the heterogeneous horizon was obtained by electrical resistivity measurements. Several two-dimensional cuts with different structures were extracted from this 3D block so that we can simulate on them the hydraulic functioning of the horizon by the Hydrus2D software. The equivalent water retention curve was obtained thanks to the additive properties of the water retention curves at the local scale. The equivalent unsaturated hydraulic conductivity of the horizon was determined on each 2D cut, which requires the knowledge of the structure. The calculations were done by two methods, a numerical one that simulated the water flow for a constant hydraulic potential, a analytical

  12. Fermion tunneling from dynamical horizons

    NASA Astrophysics Data System (ADS)

    Di Criscienzo, R.; Vanzo, L.

    2008-06-01

    The instability against emission of fermionic particles by the trapping horizon of an evolving black hole is analyzed and confirmed using the Hamilton-Jacobi tunneling method. This method automatically selects one special expression for the surface gravity of a changing horizon. The results also apply to point masses embedded in an expanding universe. As a bonus of the tunneling method, we gain the insight that the surface gravity still defines a temperature parameter as long as the evolution is sufficiently slow that the black-hole pass through a sequence of quasi-equilibrium states, and that black holes should be semi-classically unstable even in a hypothetical world without bosonic fields.

  13. Penrose inequality and apparent horizons

    SciTech Connect

    Ben-Dov, Ishai

    2004-12-15

    A spherically symmetric spacetime is presented with an initial data set that is asymptotically flat, satisfies the dominant energy condition, and such that on this initial data M<{radical}(A/16{pi}), where M is the total mass and A is the area of the apparent horizon. This provides a counterexample to a commonly stated version of the Penrose inequality, though it does not contradict the true Penrose inequality.

  14. Toroidal horizons in binary black hole mergers

    NASA Astrophysics Data System (ADS)

    Bohn, Andy; Kidder, Lawrence E.; Teukolsky, Saul A.

    2016-09-01

    We find the first binary black hole event horizon with a toroidal topology. It has been predicted that generically the event horizons of merging black holes should briefly have a toroidal topology. However, such a phase has never been seen in numerical simulations. Instead, in all previous simulations, the topology of the event horizon transitions directly from two spheres during the inspiral to a single sphere as the black holes merge. We find a coordinate transformation to a foliation of spacelike hypersurfaces that "cut a hole" through the event horizon surface, resulting in a toroidal event horizon, thus reconciling the numerical work with theoretical expectations. The demonstration requires extremely high numerical precision, which is made possible by a new event horizon code described in a companion paper. A torus could potentially provide a mechanism for violating topological censorship. However, these toroidal event horizons satisfy topological censorship by construction, because we can always trivially apply the inverse coordinate transformation to remove the topological feature.

  15. Future Economics of Liver Transplantation: A 20-Year Cost Modeling Forecast and the Prospect of Bioengineering Autologous Liver Grafts

    PubMed Central

    Habka, Dany; Mann, David; Landes, Ronald; Soto-Gutierrez, Alejandro

    2015-01-01

    During the past 20 years liver transplantation has become the definitive treatment for most severe types of liver failure and hepatocellular carcinoma, in both children and adults. In the U.S., roughly 16,000 individuals are on the liver transplant waiting list. Only 38% of them will receive a transplant due to the organ shortage. This paper explores another option: bioengineering an autologous liver graft. We developed a 20-year model projecting future demand for liver transplants, along with costs based on current technology. We compared these cost projections against projected costs to bioengineer autologous liver grafts. The model was divided into: 1) the epidemiology model forecasting the number of wait-listed patients, operated patients and postoperative patients; and 2) the treatment model forecasting costs (pre-transplant-related costs; transplant (admission)-related costs; and 10-year post-transplant-related costs) during the simulation period. The patient population was categorized using the Model for End-Stage Liver Disease score. The number of patients on the waiting list was projected to increase 23% over 20 years while the weighted average treatment costs in the pre-liver transplantation phase were forecast to increase 83% in Year 20. Projected demand for livers will increase 10% in 10 years and 23% in 20 years. Total costs of liver transplantation are forecast to increase 33% in 10 years and 81% in 20 years. By comparison, the projected cost to bioengineer autologous liver grafts is $9.7M based on current catalog prices for iPS-derived liver cells. The model projects a persistent increase in need and cost of donor livers over the next 20 years that’s constrained by a limited supply of donor livers. The number of patients who die while on the waiting list will reflect this ever-growing disparity. Currently, bioengineering autologous liver grafts is cost prohibitive. However, costs will decline rapidly with the introduction of new manufacturing

  16. Graduate Student Teacher Training: Still Relevant (And Missing?) 20 Years Later

    ERIC Educational Resources Information Center

    Blouin, David D.; Moss, Alison R.

    2015-01-01

    Twenty years ago, Pescosolido and Milkie (1995) reported that 50 percent of U.S. and Canadian sociology graduate programs offered formal teacher training. Despite pronouncements that offerings have increased substantially, no similarly thorough and direct investigation has been published since. In this time of dramatic change and increasing…

  17. 20+ Years of Environmental Education Centers in Greece: Teachers' Perceptions and Future Challenges

    ERIC Educational Resources Information Center

    Yanniris, Constantinos

    2015-01-01

    For the first time after decades of expansion and systematic innovative practice, environmental education in Greece faces an uncertain future as a result of the contemporary political and economic crisis. This research aims to contribute to the international exchange of good practices by focusing on the effects and functions of the Greek network…

  18. Maxus challenges fracture techniques, brings in the best wells in 20 years

    SciTech Connect

    Lyle, D.

    1995-10-01

    Combining a look at old ideas and new techniques gave Maxus a string of better Texas Panhandle wells. This report describes the results of an analysis performed utilizing the program FRACPRO which has real time analysis capabilities. The analysis indicated poor proppant placement.

  19. Reflections from 20 years of onion breeding and genetics: Where do we go next?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic studies of onion are challenging due to the biennial generation time and relatively high costs of producing segregating families. Before 1990, the genetic bases of numerous morphological traits and disease resistances had been determined, however only one genetic linkage was reported between...

  20. Determinants of Aortic Root Dilatation and Reference Values Among Young Adults Over a 20-Year Period: Coronary Artery Risk Development in Young Adults Study.

    PubMed

    Teixido-Tura, Gisela; Almeida, Andre L C; Choi, Eui-Young; Gjesdal, Ola; Jacobs, David R; Dietz, Harry C; Liu, Kiang; Sidney, Stephen; Lewis, Cora E; Garcia-Dorado, David; Evangelista, Artur; Gidding, Samuel; Lima, João A C

    2015-07-01

    Aortic size increases with age, but factors related to such dilatation in healthy young adult population have not been studied. We aim to evaluate changes in aortic dimensions and its principal correlates among young adults over a 20-year time period. Reference values for aortic dimensions in young adults by echocardiography are also provided. Healthy Coronary Artery Risk Development in Young Adults (CARDIA) study participants aged 23 to 35 years in 1990-1991 (n=3051) were included after excluding 18 individuals with significant valvular dysfunction. Aortic root diameter (ARD) by M-mode echocardiography at year-5 (43.7% men; age, 30.2 ± 3.6 years) and year-25 CARDIA exams was obtained. Univariable and multivariable analyses were performed to assess associations of ARD with clinical data at years-5 and -25. ARD from year-5 was used to establish reference values of ARD in healthy young adults. ARD at year-25 was greater in men (33.3 ± 3.7 versus 28.7 ± 3.4 mm; P<0.001) and in whites (30.9 ± 4.3 versus 30.5 ± 4.1 mm; P=0.006). On multivariable analysis, ARD at year-25 was positively correlated with male sex, white ethnicity, age, height, weight, 20-year gain in weight, active smoking at baseline, and 20-year increase in diastolic, systolic, and mean arterial pressure. A figure showing the estimated 95th percentile of ARD by age and body surface area stratified by race and sex is provided. This study demonstrates that smoking, blood pressure, and increase in body weight are the main modifiable correlates of aortic root dilation during young adulthood. Our study also provides reference values for ARD in young adults.

  1. Maternal deaths in eastern Indonesia: 20 years and still walking: an ethnographic study

    PubMed Central

    2014-01-01

    Background The delays in receiving adequate emergency maternal care described by Thaddeus and Maine twenty years ago are still occurring, as exemplified in this study of cases of maternal deaths in a subdistrict in rural eastern Indonesia. Methods An ethnographic design was conducted, recruiting eleven families who reported on cases of maternal deaths in one sub-district of Indonesia, as well as assessing the geographical and cultural context of the villages. Traditional birth attendants and village leaders provided information to the research team which was thematically and contextually analysed. Results Two stages to the first and second delays have been differentiated in this study. First, delays in the decision to seek care comprised time taken to recognise (if at all) that an emergency situation existed, followed by time taken to reach a decision to request care. The decision to request care resided variously with the family or cadre. Second, delays in reaching care comprised time taken to deliver the request for help and then time for help to arrive. A phone was not available to request care in many cases and so the request was delivered by walking or motorbike. In two cases where the decision to seek care and the delivery of the request happened in a timely way, help was delayed because the midwife and ambulance respectively were unavailable. Conclusions This study, although a small sample, confirmed that either a single delay or a sequence of delays can prove fatal. Delays were determined by both social and geographic factors, any of which alone could be limiting. Initiatives to improve maternal health outcomes need to address multiple factors: increased awareness of equitable access to maternal health care, village preparedness for emergency response, improved access to telecommunications and geographic access. PMID:24447873

  2. Radio-induced gliomas: 20-year experience and critical review of the pathology.

    PubMed

    Salvati, Maurizio; D'Elia, Alessandro; Melone, Graziella Angelina; Brogna, Christian; Frati, Alessandro; Raco, Antonino; Delfini, Roberto

    2008-09-01

    The authors report their personal experience with a surgical series of 16 cases of cerebral radiation-induced gliomas, defining diagnostic criteria and surgical and clinical characteristics. There were ten males and six females, with a median age of 45.9 years. Irradiation had initially been given for acute lymphoblastic leukemia (ALL) in six cases, tinea capitis in four cases, scalp hemangioma in three cases, cutaneous hemangioma, cavernous angioma, and medulloblastoma in one case each. There were 14 cases of glioblastoma (grade IV WHO) and 2 cases of astrocytoma (grade II WHO), with a mean latency time of 17 years (range: 6-26 years). For glioblastomas mean survival time was 10.4 months, accounting for 1-3% of all the glioblastomas treated. A thorough revision of the pertinent literature revealed some clinical-biological peculiarities.

  3. A 20-Year Perspective on Preparation Strategies and Career Planning of Pharmacy Deans

    PubMed Central

    Plaza, Cecilia M.

    2010-01-01

    Objective To provide a longitudinal description of the variety of career paths and preparation strategies of pharmacy deans. Methods A descriptive cross-sectional study design using survey research methodology was used. Chief executive officer (CEO) deans at every full and associate member institution of the American Association of Colleges of Pharmacy (AACP) in the United States as of May 1, 2009, were potential subjects. Results The database housed 90.3% (N = 93) of all current (excluding interim/acting) CEO deans. Of the 4 cohorts across time (1991, 1996, 2002, and 2009 snapshots), the 2009 cohort had the highest percentage of deans following either the hierarchical or nontraditional career paths. Conclusions Deans named since 2002 have spent less time collectively in the professoriate than cohorts before them. One reason for this is the increase in the number of deans that followed nontraditional career paths and who spent little or no time in the professoriate prior to their first deanship. This also could be due to the increased demand for individuals to serve as dean due to retirements and the creation of new institutions. PMID:21301596

  4. Beyond the veil: Inner horizon instability and holography

    SciTech Connect

    Balasubramanian, Vijay; Levi, Thomas S.

    2004-11-15

    We show that scalar perturbations of the eternal, rotating Banados-Teitelboim-Zanelli (BTZ) black hole should lead to an instability of the inner (Cauchy) horizon, preserving strong cosmic censorship. Because of backscattering from the geometry, plane-wave modes have a divergent stress tensor at the event horizon, but suitable wave packets avoid this difficulty, and are dominated at late times by quasinormal behavior. The wave packets have cuts in the complexified coordinate plane that are controlled by requirements of continuity, single-valuedness, and positive energy. Due to a focusing effect, regular wave packets nevertheless have a divergent stress energy at the inner horizon, signaling an instability. We propose that this instability, which is localized behind the event horizon, is detected holographically as a breakdown in the semiclassical computation of dual conformal field theory (CFT) expectation values in which the analytic behavior of wave packets in the complexified coordinate plane plays an integral role. In the dual field theory, this is interpreted as an encoding of physics behind the horizon in the entanglement between otherwise independent CFTs.

  5. Persistence of immunoglobulin M or immunoglobulin G antibody responses to Borrelia burgdorferi 10-20 years after active Lyme disease.

    PubMed

    Kalish, R A; McHugh, G; Granquist, J; Shea, B; Ruthazer, R; Steere, A C

    2001-09-15

    The interpretation of serological results for patients who had Lyme disease many years ago is not well defined. We studied the serological status of 79 patients who had had Lyme disease 10-20 years ago and did not currently have signs or symptoms of active Lyme disease. Of the 40 patients who had had early Lyme disease alone, 4 (10%) currently had IgM responses to Borrelia burgdorferi, and 10 (25%) still had IgG reactivity to the spirochete, as determined by a 2-test approach (enzyme-linked immunosorbent assay and Western blot). Of the 39 patients who had had Lyme arthritis, 6 (15%) currently had IgM responses and 24 (62%) still had IgG reactivity to the spirochete. IgM or IgG antibody responses to B. burgdorferi may persist for 10-20 years, but these responses are not indicative of active infection.

  6. Oil sheen weathering post Deepwater Horizon

    NASA Astrophysics Data System (ADS)

    Kellermann, M. Y.; Redmond, M. C.; Reddy, C. M.; Aeppli, C.; Nelson, R. K.; Valentine, D. L.

    2013-12-01

    A recently published study identified the source of the reoccurred oil sheens close to the Deepwater Horizon (DWH) disaster site as a finite contamination most likely derived from tanks and pits on the DWH wreckage itself. Here we use geochemical fingerprinting and microbial community analysis to better understand the fate and weathering processes affecting these surface oils. Both, alkanes and polycyclic aromatic hydrocarbons (PAHs) are shown to reflect a linear decrease of hydrocarbon compounds with increasing distance to the DWH wreckage site (equivalent to exposure time on the sea surface). These results indicate that in the early stage of weathering the combined effects of dissolution and evaporation dominate the degradation of these surface oils. Sheen microbial communities were dominated by Cyanobacteria, Planctomycetes, Verrucomicrobia, Flavobacteria, Alphaproteobacteria, and Deltaproteobacteria, with low relative abundances of Gammaproteobacteria likely to be hydrocarbon degraders (no more than 15% of sequences in each sample). However, some of these Gammaproteobacteria were closely related to putative hydrocarbon degraders observed in abundance in deep water plumes during the primary Deepwater Horizon spill, suggesting that very low levels of biodegradation may be also occurring. This in situ weathering experiment provides new insights in hydrocarbon weathering dynamics and shows how chemical and biological changes can potentially be masked by large evaporative losses of compounds smaller than C18 n-alkanes.

  7. Playing Darwin. Part B. 20 years of domestication in Drosophila subobscura.

    PubMed

    Santos, Marta; Fragata, Inês; Santos, Josiane; Simões, Pedro; Marques, Ana; Lima, Margarida; Matos, Margarida

    2010-09-01

    Adaptation to a new environment (as well as its underlying mechanisms) is one of the most important topics in Evolutionary Biology. Understanding the adaptive process of natural populations to captivity is essential not only in general evolutionary studies but also in conservation programmes. Since 1990, the Group of Experimental Evolution (CBA/FCUL) has been performing long-term, real-time evolutionary studies, with the characterization of laboratory adaptation in populations of Drosophila subobscura founded in different times and from different locations. Initially, these experiments involved phenotypic assays and more recently were expanded to studies at the molecular level (microsatellite and chromosomal polymorphisms) and with different population sizes. Throughout these two decades, a clear pattern of evolutionary convergence to long-established laboratory populations has been consistently observed in several life-history traits. However, contingencies across foundations were also found during the adaptive process. In characters with complex evolutionary trajectories, the data suggested that the comparative method lacked predictive capacity relative to real-time evolutionary trajectories (experimental evolution). Microsatellite analysis revealed general similarity in gene diversity and allele number between studied populations, as well as an unclear association between genetic variability and evolutionary potential. Nevertheless, ongoing studies in all foundations are being carried out to further test this hypothesis. A comparison between recently introduced and long-term populations (founded from the same natural location) has shown higher degree of chromosomal polymorphism in recent ones. Finally, our findings suggest higher heterogeneity between small-sized populations, as well as a slower evolutionary rate in characters close to fitness (such as fecundity and mating behaviour). This comprehensive study is aimed at better understanding the processes and

  8. Primary pulmonary artery sarcoma: a close associate of pulmonary embolism—20-year observational analysis

    PubMed Central

    Panchabhai, Tanmay S.; Bajaj, Navkaranbir S.; Patil, Pradnya D.; Bunte, Matthew C.

    2016-01-01

    Background Primary pulmonary artery sarcoma (PPAS) is a rare tumor that mimics pulmonary thromboembolism (PE). Similarities to PE can delay the diagnosis and misguide the treatment of PPAS. This study aimed to evaluate tumor characteristics and outcome predictors among those diagnosed with PPAS and misdiagnosed as PE. Methods From 1991–2010, 10 PPAS cases were available from the Cleveland Clinic (CC) institutional database and another 381 cases were reported in the literature. Patient characteristics, tumor subtypes, diagnostic testing & timing, interventions and clinical outcomes were analyzed. We also noted effects of misdiagnosis as PE and clinical outcome as a result of inappropriate intervention. Results Among 391 confirmed cases of PPAS, the mean age at diagnosis was 52±14 years; 55% were male. The median duration of symptoms prior to diagnosis was 100 [interquartile range (IQR), 30–210] days. Nearly half (47%) of PPAS were originally misdiagnosed as PE including 39% that received thrombolytic and/or anticoagulation therapy. For every doubling of time from symptom onset to diagnosis, the odds of death increased by 46% (OR: 1.46, 95% CI: 1.21–1.82; P<0.001). The odds of death (OR: 2.66, 95% CI: 1.58–4.54; P=0.0003) and occurrence of distant metastasis (OR: 2.30, 95% CI: 1.30–4.15; P=0.049) were increased among those who did not receive chemotherapy but chemotherapy did not impact local recurrence. Those with complete resection had a better survival. Conclusions PPAS has a radiological appearance similar to PE, which makes accurate and timely diagnosis challenging. More rapid diagnosis may lead to earlier, appropriate surgical treatment and improved outcomes, when combined with adjuvant treatment.

  9. Horizontal and vertical deformation field in New Caledonia, South West Pacific, derived from more than 20 years of GNSS measurements

    NASA Astrophysics Data System (ADS)

    Ballu, V.; Calmant, S.; Valty, P.; Gravelle, M.; Sakic, P.; Aucan, J.; Pelletier, B.

    2015-12-01

    New Caledonia is located in the South West Pacific Ocean, on the Australian Plate just before its subduction under the North Fiji Basin. Because it is on the subducting side of the plate interface, New Caledonia is considered to be stable to first order and not to undergo rapid deformation. However, moderate seismicity is recorded close to the plate interface, in the southern part of the main land and along the Loyalty ridge. In addition, the main island and Loyalty ridge are subjected to long-term vertical deformation due to the flexure of the plate entering subduction. A geodetic network was installed since the early days of GPS (~1990) and has been further developed and occasionally measured since. Due to the low number of global GNSS recording stations in the early 1990s, the positioning accuracy that can be achieved with these data is poor compared to present-day standards, and expected movements are slow (possibly less than 1 mm/yr). However, the >20 year length of the time series may allow us to determine the current deformation field in New Caledonia and Loyalty Ridge. We pay special care in using older GNSS data for characterizing ground motions, reprocessing all available data using a range of different processing strategies and products. We calculated daily positions from double-differenced ionosphere-free carrier phase data in a global network using the GAMIT software and combined and aligned the results on the ITRF2008 using the CATREF software, according to the processing strategy developed as part of the current ULR6 (www.sonel.org) reprocessing campaign for IGS. We compare the double difference results with those obtained in PPP mode using JPL GIPSY software as well as CNES GINS software and different products (MIT, JPL and GRG orbits and clocks provided in the framework of the IGS2 reprocessing campaign). We present both the results for New Caledonia and an analysis of the applicability of these different processing strategies to older GNSS

  10. Lessons about Virtual-Environment Software Systems from 20 years of VE building

    PubMed Central

    Taylor, Russell M.; Jerald, Jason; VanderKnyff, Chris; Wendt, Jeremy; Borland, David; Marshburn, David; Sherman, William R.; Whitton, Mary C.

    2010-01-01

    What are desirable and undesirable features of virtual-environment (VE) software architectures? What should be present (and absent) from such systems if they are to be optimally useful? How should they be structured? To help answer these questions we present experience from application designers, toolkit designers, and VE system architects along with examples of useful features from existing systems. Topics are organized under the major headings of: 3D space management, supporting display hardware, interaction, event management, time management, computation, portability, and the observation that less can be better. Lessons learned are presented as discussion of the issues, field experiences, nuggets of knowledge, and case studies. PMID:20567602

  11. Dietary pattern and 20 year mortality in elderly men in Finland, Italy, and The Netherlands: longitudinal cohort study.

    PubMed Central

    Huijbregts, P.; Feskens, E.; Räsänen, L.; Fidanza, F.; Nissinen, A.; Menotti, A.; Kromhout, D.

    1997-01-01

    OBJECTIVE: To investigate the association of dietary pattern and mortality in international data. DESIGN: Cohort study with 20 years' follow up of mortality. SETTING: Five cohorts in Finland, the Netherlands, and Italy. SUBJECTS: Population based random sample of 3045 men aged 50-70 years in 1970. MAIN OUTCOME MEASURES: Food intake was estimated using a cross check dietary history. In this dietary survey method, the usual food consumption pattern in the 6-12 months is estimated. A healthy diet indicator was calculated for the dietary pattern, using the World Health Organisation's guidelines for the prevention of chronic diseases. Vital status was verified after 20 years of follow up, and death rates were calculated. RESULTS: Dietary intake varied greatly in 1970 between the three countries. In Finland and the Netherlands the intake of saturated fatty acids and cholesterol was high and the intake of alcohol was low; in Italy the opposite was observed. In total 1796 men (59%) died during 20 years of follow up. The healthy diet indicator was inversely associated with mortality (P for trend < 0.05). After adjustment for age, smoking, and alcohol consumption, the relative risk in the group with the healthiest diet indicator compared with the group with the least healthy was 0.87 (95% confidence interval 0.77 to 0.98). Estimated relative risks were essentially similar within each country. CONCLUSIONS: Dietary intake of men aged 50-70 is associated with a 20 year, all cause mortality in different cultures. The healthy diet indicator is useful in evaluating the relation of mortality to dietary patterns. PMID:9233319

  12. Long-term importance of fundamental motor skills: a 20-year follow-up study.

    PubMed

    Lloyd, Meghann; Saunders, Travis J; Bremer, Emily; Tremblay, Mark S

    2014-01-01

    The purpose of this study was to investigate the potential long-term association of motor skill proficiency at 6 years of age and self-reported physical activity (PA) at age 26. Direct motor performance data were collected in 1991 with a follow-up study occurring in 1996, and then indirect questionnaires (self-report) administered in 2001 and 2011. In 2011, 17 participants who were identified as either having high motor proficiency (HMP) or low motor proficiency (LMP) in 1991 completed a series of 4 questionnaires. Analyses were conducted to determine whether there were differences between groups for motor skill proficiency, PA, or sedentary behavior, and whether these outcomes were related across ages. Motor skill proficiency at age 6 was related to self-reported proficiency at age 16 (r = .77, p = .006), and self-reported proficiency between 16 and 26 years (r = .85, p = .001). Motor skill proficiency at age 6 was positively associated with leisure time PA at age 26 in females and participants in the HMP group. The results may provide preliminary evidence about the importance of how early motor skill proficiency relates to long-term PA. More research with larger sample sizes is needed to investigate the importance of motor skills over time.

  13. FORENSIC SCIENCE:: 20 YEARS OF FORENSIC DENTISTRY AT THE UNIVERSITY OF ZAGREB, 1994 - 2014.

    PubMed

    Brkić, Hrvoje

    2014-06-01

    Data from available literature point to an early beginning of Forensic Dentistry in Croatia relating to a post-mortem examination of a female patient after a dental procedure in the 1930s. Later on, there were several mass casualties due to collisions and airplane crashes and a railway accident at the Zagreb Main Railway Station wherein the identity of the victims was established based on dental features. Foreign experts in forensics helped identify those victims, particularly forensic dentists because this specialty was almost unknown in our region at the time. During the twenty-year period of the development of Forensic Dentistry at the University of Zagreb, the School of Dental Medicine, the city of Zagreb and Croatia have become internationally recognised on the forensic map of the world.

  14. The 20-Year Trajectory of Marital Quality in Enduring Marriages: Does Equity Matter?

    PubMed Central

    DeMaris, Alfred

    2011-01-01

    I examine the trajectory of marital quality as a function of relationship equity with data from a six-wave panel study of 704 married respondents between 1980 and 2000. Reporting that one “gives more” to the marriage (subjective underbenefit) is more likely for women than men at any given marital duration. Respondent’s relative contribution to income, paid labor, housework, and health (objective underbenefit) raises this probability for women of average religiosity. For the more religious, objective underbenefit has no effect on women’s sense of underbenefit, but reduces men’s sense of underbenefit. Objective underbenefit lowers women’s, but raises men’s, marital quality, at any marital duration. The relevance of equity was not diluted by the passage of time in marriage. PMID:21966079

  15. Assessment of the Main Natural Disturbances on Norwegian Forest Based on 20 Years of National Inventory.

    PubMed

    Díaz-Yáñez, Olalla; Mola-Yudego, Blas; Eriksen, Rune; González-Olabarria, José Ramón

    2016-01-01

    The re-measurement of permanent forest inventories offers a unique opportunity to assess the occurrence and impact of forest disturbances. The present study aims at exploring the main forest damages in Norway based on the extensive data of several consecutive national forest inventories during the period 1995-2014. Five of the most common disturbance agents in Norway are selected for analysis: wind, snow, browsing, fungus and insect damage. The analyses focuses on the frequency and variation along time, the average damage at stand level and the spatial patterns of damage occurrence, resulting in a characterization of the damage produced by disturbances in Norway. The highest damage occurrences by disturbance agent are due to browsing, snow and wind. Snow presents a decreasing temporally trend in damage frequency in the studied period. By forest type, mature and intermediate birch forest are found to be more affected by snow damage, whereas mature spruce forest is by wind damage. The results from this study provide support to the hypothesis that damages by autumnal moth (Epirrita autumnata) on birch are more common in mature stands. No major attacks from bark beetle (Ips typographus) are found, probably related to the lack of major storm damages in the period. Forest types susceptibility to fungus has no apparent variation over time except in the last years, as increased occurrence is observed on mature spruce stands probably correlated with warmer than average periods. Browsing damage causes the most severe losses, as expected, in young stands, and is allocated mainly on the most productive forests. Although some of the disturbances present locally moderate effects, the results show no major disturbances threatening Norwegian forests in the studied period. Finally, the Norwegian national forest inventory demonstrates its reliability as a basis to understand the occurrence and effects of major natural disturbances. PMID:27570973

  16. Assessment of the Main Natural Disturbances on Norwegian Forest Based on 20 Years of National Inventory

    PubMed Central

    Mola-Yudego, Blas; Eriksen, Rune; González-Olabarria, José Ramón

    2016-01-01

    The re-measurement of permanent forest inventories offers a unique opportunity to assess the occurrence and impact of forest disturbances. The present study aims at exploring the main forest damages in Norway based on the extensive data of several consecutive national forest inventories during the period 1995–2014. Five of the most common disturbance agents in Norway are selected for analysis: wind, snow, browsing, fungus and insect damage. The analyses focuses on the frequency and variation along time, the average damage at stand level and the spatial patterns of damage occurrence, resulting in a characterization of the damage produced by disturbances in Norway. The highest damage occurrences by disturbance agent are due to browsing, snow and wind. Snow presents a decreasing temporally trend in damage frequency in the studied period. By forest type, mature and intermediate birch forest are found to be more affected by snow damage, whereas mature spruce forest is by wind damage. The results from this study provide support to the hypothesis that damages by autumnal moth (Epirrita autumnata) on birch are more common in mature stands. No major attacks from bark beetle (Ips typographus) are found, probably related to the lack of major storm damages in the period. Forest types susceptibility to fungus has no apparent variation over time except in the last years, as increased occurrence is observed on mature spruce stands probably correlated with warmer than average periods. Browsing damage causes the most severe losses, as expected, in young stands, and is allocated mainly on the most productive forests. Although some of the disturbances present locally moderate effects, the results show no major disturbances threatening Norwegian forests in the studied period. Finally, the Norwegian national forest inventory demonstrates its reliability as a basis to understand the occurrence and effects of major natural disturbances. PMID:27570973

  17. Sympathetic neural reactivity to mental stress in offspring of hypertensive parents: 20 years revisited.

    PubMed

    Fonkoue, Ida T; Wang, Min; Carter, Jason R

    2016-08-01

    A number of recent studies have highlighted large interindividual variability of muscle sympathetic nerve activity (MSNA) responsiveness to mental stress in humans. The purpose of this study was to examine blood pressure (BP) and MSNA responsiveness to mental stress in a large and generalizable cohort of young adults with and without family history of hypertension (FHH). We hypothesized that subjects with FHH would demonstrate greater sympathoexcitation to mental stress than subjects without FHH. A total of 87 subjects (55 men and 32 women, 18-40 yr of age) from recently published (n = 45) and ongoing (n = 42) studies were examined; 57 subjects (19 with FHH and 38 without FHH) had complete MSNA recordings at baseline. Heart rate (HR), BP, and MSNA were recorded during 5 min of supine rest and 5 min of mental stress (mental arithmetic). Resting MSNA and HR were not statistically different between subjects with and without FHH (P > 0.05), whereas resting mean arterial pressure was higher in subjects with FHH (86 ± 2 vs. 80 ± 1 mmHg, P < 0.05). Mental stress increased MSNA in subjects with FHH (Δ5 ± 1 bursts/min), but not in subjects without FHH [Δ1 ± 1 burst/min, P < 0.01 (time × group)]. Mental stress increased mean arterial pressure (Δ12 ± 1 and Δ10 ± 1 mmHg, P < 0.001) and HR (Δ19 ± 2 and Δ16 ± 2 beats/min, P < 0.001) in subjects with and without FHH, but these increases were not different between groups [P ≥ 0.05 (time × group)]. MSNA and BP reactivity to mental stress were not correlated in either group. In conclusion, FHH was associated with heightened MSNA reactivity to mental stress, despite a dissociation between MSNA and BP responsiveness. PMID:27371684

  18. Gravitational radiations of generic isolated horizons and nonrotating dynamical horizons from asymptotic expansions

    SciTech Connect

    Wu, Y.-H.; Wang, C.-H.

    2009-09-15

    Instead of using a three-dimensional analysis on quasilocal horizons, we adopt a four-dimensional asymptotic expansion analysis to study the next order contributions from the nonlinearity of general relativity. From the similarity between null infinity and horizons, the proper reference frames are chosen from the compatible constant spinors for an observer to measure the energy-momentum and flux near quasilocal horizons. In particular, we focus on the similarity of Bondi-Sachs gravitational radiation for the quasilocal horizons and compare our results with Ashtekar-Kirshnan flux formula. The quasilocal energy-momentum and flux of generic isolated horizons and nonrotating dynamical horizons are discussed in this paper.

  19. Topological deformation of isolated horizons

    SciTech Connect

    Liko, Tomas

    2008-03-15

    We show that the Gauss-Bonnet term can have physical effects in four dimensions. Specifically, the entropy of a black hole acquires a correction term that is proportional to the Euler characteristic of the cross sections of the horizon. While this term is constant for a single black hole, it will be a nontrivial function for a system with dynamical topologies such as black-hole mergers: it is shown that for certain values of the Gauss-Bonnet parameter, the second law of black-hole mechanics can be violated.

  20. Lessons Learned from 20 Years of Production in the Barnett Shale

    NASA Astrophysics Data System (ADS)

    Gupta, R.; Middleton, R. S.; Carey, J. W.; Currier, R.; Karra, S.; Viswanathan, H.

    2014-12-01

    We analyze a 22 years of shale gas production, from more than 18,000 wells, in the Barnett formation to better characterize and understand shale gas production. The Barnett Shale formation has a relatively long history of exploration and shale gas production using both hydraulic fracturing and horizontal wells. The original Barnett well, a vertical well that used a nitrogen foam working fluid, dates back to 1981, and the first horizontal wells were drilled in 1991. However, the first "successful" production wells were not drilled until around 1997-1998. Gas production data for the Barnett is publicly available dating back to 1993. Here, we analyze gas production from ~18,000 individual wells (data collected in July 2014) in order to understand and quantify how shale gas has been produced in the Barnett. This includes understanding how and when shale gas production techniques have improved resulting in enhanced gas production. Several key trends and hypotheses emerge from this analysis. For example, the data shows a distinct and strong pattern of "learning by doing", whereby per-well gas production rates have notably increased over time. For example, a typical well drilled in 2011 takes three years to produce 1,000 MMcf, whereas a typical 2007 well takes seven years to produce the same quantity. The data can also be differentiated by parameters such as depth and well type (principally vertical vs. horizontal); we show a clear link between drilling techniques and production. The analysis also reveals unexpected outcomes. For instance, wells drilled in the period 1994-1999 have greater cumulative production than wells drilled in the period 2000-2006. We hypothesize that the older wells often performed poorly when first drilled and were thus subsequently re-fractured one or more times, whereas the later wells were re-fractured much less frequently. Finally, we compare shale gas production from the Barnett formation with more recent production from the Hayneville

  1. [Effects of Slope Position and Soil Horizon on Soil Microbial Biomass and Abundance in Karst Primary Forest of Southwest China].

    PubMed

    Feng, Shu-zhen; Su, Yi-rong; Zhang, Wei; Chen, Xiang-bi; He, Xun-yang

    2015-10-01

    To explore the effects of slope position and soil horizon on soil microbial biomass and abundance, chloroform fumigation extraction methods and real-time fluorescence-based quantitative PCR (Real-time PCR) were adopted to quantify the changes of soil microbial biomass C, N and abundance of bacteria and fungi, respectively. Soil samples were harvested from three horizons along profile, i. e., leaching horizon (A, 0-10 cm), transitional horizon (AB, 30-50 cm) and alluvial horizon (B, 70-100 cm), which were collected from the upper, middle and lower slope positions of a karst primary forest ecosystem. The results showed that slope position, soil horizon and their interaction significantly influenced the soil microbial biomass and abundance (P < 0.05). Different from A horizon, where SMBC was greater in lower than in upper slope position (P < 0.05), SMBC in AB and B horizons were highest in middle slope position. Similarly, SMBN was greater in lower than in upper slope position for A, AB and B horizons. Besides soil bacterial abundance in B horizon and fungal abundance in AB layer, the middle slope position had the highest value for all the three soil horizons (P < 0.05). Stepwise regression analysis showed that soil organic carbon, available nitrogen and pH were the key factors responsible for SMBC and SMBN variation, respectively, while the important factors responsible for the variation of bacteria abundance were available nitrogen and available phosphorus, and that for fungi abundance variation were available potassium.

  2. Particle Fluxes in the Marginal Seas of Antarctica: A 20-year Synthesis in Honor of Jack Dymond

    NASA Astrophysics Data System (ADS)

    Dunbar, R. B.; Langone, L.

    2004-12-01

    One of Jack Dymond's long-standing scientific passions was the study of particles moving through the ocean water column. Jack's pioneering work in this area in the 1970's and generous mentoring of others throughout his career lead directly to the first authors involvement in sediment trap studies. Here we present a synthesis of 20 years of particle flux studies in coastal Antarctic (including the work of Collier and Dymond et al.) and highlight some of the important features and unresolved issues related to integrating particle trap interceptor data with other measures of production, transport, and deposition. The first sediment trap arrays were deployed on the Antarctic shelf in 1981 and 1982 in the Antarctic Peninsula. Simple instruments were also deployed in 1984 and 1986 in the Ross Sea. Since then, several nations (US, Italy, New Zealand) have recovered time series sediment trap data on moorings in both of these areas. This current synthesis makes use of data from approximately 22 sites, the majority of which are in the Ross Sea, and includes about 900 discrete samples of particles in vertical transit through the water column. We now have many complete time series that extend through the winter, allowing several important generalizations to be made. For example, annual particle-mediated organic C fluxes to below 200 meters in the Ross Sea average 4.4±3.3 g C m-2 yr-1. These values are significantly less than export fluxes calculated using short-term surface water mass balance approaches or Th isotope techniques yet are higher than seabed sediment accumulation rates. Intriguingly, seasonal seabed arrival rates of organic C estimated from in-situ summertime benthic respirometry studies yield C flux values similar in magnitude to those from sediment traps deployed at the same time, lending strong support to trap data. The cause of current disagreements between various methods of flux estimation may in fact not be solved until process studies are accomplished

  3. Cytochrome P4501A biomarker indication of oil exposure in harlequin ducks up to 20 years after the Exxon Valdez oil spill.

    PubMed

    Esler, Daniel; Trust, Kimberly A; Ballachey, Brenda E; Iverson, Samuel A; Lewis, Tyler L; Rizzolo, Daniel J; Mulcahy, Daniel M; Miles, A Keith; Woodin, Bruce R; Stegeman, John J; Henderson, John D; Wilson, Barry W

    2010-05-01

    Hydrocarbon-inducible cytochrome P4501A (CYP1A) expression was measured, as ethoxyresorufin-O-deethylase (EROD) activity, in livers of wintering harlequin ducks (Histrionicus histrionicus) captured in areas of Prince William Sound, Alaska, USA, oiled by the 1989 Exxon Valdez spill and in birds from nearby unoiled areas, during 2005 to 2009 (up to 20 years following the spill). The present work repeated studies conducted in 1998 that demonstrated that in harlequin ducks using areas that received Exxon Valdez oil, EROD activity was elevated nearly a decade after the spill. The present findings strongly supported the conclusion that average levels of hepatic EROD activity were higher in ducks from oiled areas than those from unoiled areas during 2005 to 2009. This result was consistent across four sampling periods; furthermore, results generated from two independent laboratories using paired liver samples from one of the sampling periods were similar. The EROD activity did not vary in relation to age, sex, or body mass of individuals, nor did it vary strongly by season in birds collected early and late in the winter of 2006 to 2007, indicating that these factors did not confound inferences about observed differences between oiled and unoiled areas. We interpret these results to indicate that harlequin ducks continued to be exposed to residual Exxon Valdez oil up to 20 years after the original spill. This adds to a growing body of literature suggesting that oil spills have the potential to affect wildlife for much longer time frames than previously assumed.

  4. Cytochrome P4501A biomarker indication of oil exposure in harlequin ducks up to 20 years after the Exxon Valdez oil spill.

    PubMed

    Esler, Daniel; Trust, Kimberly A; Ballachey, Brenda E; Iverson, Samuel A; Lewis, Tyler L; Rizzolo, Daniel J; Mulcahy, Daniel M; Miles, A Keith; Woodin, Bruce R; Stegeman, John J; Henderson, John D; Wilson, Barry W

    2010-05-01

    Hydrocarbon-inducible cytochrome P4501A (CYP1A) expression was measured, as ethoxyresorufin-O-deethylase (EROD) activity, in livers of wintering harlequin ducks (Histrionicus histrionicus) captured in areas of Prince William Sound, Alaska, USA, oiled by the 1989 Exxon Valdez spill and in birds from nearby unoiled areas, during 2005 to 2009 (up to 20 years following the spill). The present work repeated studies conducted in 1998 that demonstrated that in harlequin ducks using areas that received Exxon Valdez oil, EROD activity was elevated nearly a decade after the spill. The present findings strongly supported the conclusion that average levels of hepatic EROD activity were higher in ducks from oiled areas than those from unoiled areas during 2005 to 2009. This result was consistent across four sampling periods; furthermore, results generated from two independent laboratories using paired liver samples from one of the sampling periods were similar. The EROD activity did not vary in relation to age, sex, or body mass of individuals, nor did it vary strongly by season in birds collected early and late in the winter of 2006 to 2007, indicating that these factors did not confound inferences about observed differences between oiled and unoiled areas. We interpret these results to indicate that harlequin ducks continued to be exposed to residual Exxon Valdez oil up to 20 years after the original spill. This adds to a growing body of literature suggesting that oil spills have the potential to affect wildlife for much longer time frames than previously assumed. PMID:20821550

  5. Hearing Aid Satisfaction: What Does Research from the Past 20 Years Say?

    PubMed Central

    Wong, Lena L. N.; Hickson, Louise; McPherson, Bradley

    2003-01-01

    Hearing aid satisfaction is a pleasurable emotional experience as an outcome of an evaluation of performance. Many tools have been designed to measure the degree of satisfaction overall, or along the dimensions of cost, appearance, acoustic benefit, comfort, and service. Various studies have used these tools to examine the relationships between satisfaction and other factors. Findings are not always consistent across studies, but in general, hearing aid satisfaction has been found to be related to experience, expectation, personality and attitude, usage, type of hearing aids, sound quality, listening situations, and problems in hearing aid use. Inconsistent findings across studies and difficulties in evaluating the underlying relationships are probably caused by problems with the tools (eg, lack of validity) and the methods used to evaluate relationships (eg, correlation analyses evaluate association and not causal effect). Whether satisfaction changes over time and how service satisfaction contributes to device satisfaction are unclear. It is hoped that this review will help readers understand current satisfaction measures, how various factors affect satisfaction, and how the way satisfaction is measured may be improved to yield more reliable and valid data. PMID:15004650

  6. Fragile-X syndrome--a 20-year follow-up study of male patients.

    PubMed

    Arvio, M

    2016-01-01

    In 1994, a multi-professional team examined clinically 34 males with fragile X syndrome (FXS). Since then, these patients have been clinically evaluated twice at a 10-year interval. With the aid of the Portage method we were able to chart the course of their adaptive skills. The FXS males learned new abilities on average up to the age of 25; this was followed by a plateau stage until they reached 50, after which time, physical symptoms evidencing weakened overall motor skills were apparent. During follow-up, a total of 10 men died, 9 of them suddenly. Of these, three were under the age of 40 at death, and the oldest was 77. The FXS men were socially interactive, helpful, but shy. Typical symptoms of FXS boys such as poor eye contact, tactile defensiveness, and perseverative speech did not disappear with age. At the end of the study, 75% of the study subjects had long-standing health problems. Most aged over 50 suffered from symptoms arising from an enlarged prostate; one fourth were on psychotropic-, and one fifth on antiepileptic drug treatment.

  7. The molecular spectrum and distribution of haemoglobinopathies in Cyprus: a 20-year retrospective study

    PubMed Central

    Kountouris, Petros; Kousiappa, Ioanna; Papasavva, Thessalia; Christopoulos, George; Pavlou, Eleni; Petrou, Miranda; Feleki, Xenia; Karitzie, Eleni; Phylactides, Marios; Fanis, Pavlos; Lederer, Carsten W.; Kyrri, Andreani R.; Kalogerou, Eleni; Makariou, Christiana; Ioannou, Christiana; Kythreotis, Loukas; Hadjilambi, Georgia; Andreou, Nicoletta; Pangalou, Evangelia; Savvidou, Irene; Angastiniotis, Michael; Hadjigavriel, Michael; Sitarou, Maria; Kolnagou, Annita; Kleanthous, Marina; Christou, Soteroula

    2016-01-01

    Haemoglobinopathies are the most common monogenic diseases, posing a major public health challenge worldwide. Cyprus has one the highest prevalences of thalassaemia in the world and has been the first country to introduce a successful population-wide prevention programme, based on premarital screening. In this study, we report the most significant and comprehensive update on the status of haemoglobinopathies in Cyprus for at least two decades. First, we identified and analysed all known 592 β-thalassaemia patients and 595 Hb H disease patients in Cyprus. Moreover, we report the molecular spectrum of α-, β- and δ-globin gene mutations in the population and their geographic distribution, using a set of 13824 carriers genotyped from 1995 to 2015, and estimate relative allele frequencies in carriers of β- and δ-globin gene mutations. Notably, several mutations are reported for the first time in the Cypriot population, whereas important differences are observed in the distribution of mutations across different districts of the island. PMID:27199182

  8. Neighborhood socioeconomic status and food environment: a 20-year longitudinal latent class analysis among CARDIA participants

    PubMed Central

    Richardson, Andrea S.; Meyer, Katie A.; Howard, Annie Green; Boone-Heinonen, Janne; Popkin, Barry M.; Evenson, Kelly R.; Kiefe, Catarina I.; Lewis, Cora E.; Gordon-Larsen, Penny

    2014-01-01

    Cross-sectional studies suggest neighborhood socioeconomic (SES) disadvantage is associated with obesogenic food environments. Yet, it is unknown how exposure to neighborhood SES patterning through adulthood corresponds to food environments that also change over time. We used latent class analysis (LCA) to classify participants in the US-based Coronary Artery Risk Development in Young Adults study [n=5,114 at baseline 1985-1986 to 2005-2006] according to their longitudinal neighborhood SES residency patterns (upward, downward, stable high and stable low). For all classes of residents, the availability of fast food and non-fast food restaurants and supermarkets and convenience stores increased (p<0.001). Yet, socioeconomically disadvantaged neighborhood residents had fewer fast food and non-fast food restaurants, more convenience stores, and the same number of supermarkets in their neighborhoods than the advantaged residents. In addition to targeting the pervasive fast food restaurant and convenient store retail growth, improving neighborhood restaurant options for disadvantaged residents may reduce food environment disparities. PMID:25280107

  9. 20 years of reprocessed Lyapunov Exponents from altimetry available on AVISO+

    NASA Astrophysics Data System (ADS)

    Pujol, Marie-Isabelle; Faugere, Yannice; D'Ovidio, Francesco; Morrow, Rosemary; Bronner, Emilie; Picot, Nicolas

    2015-04-01

    SARAL/AltiKa is able to sample the small mesoscale signal with a noise measurement error never reached in nadir conventional altimetry. The SARAL/AltiKa 1-Hz measurement is used in the SSALTO/DUACS system since July 2013 and largely contributes to the quality of the Level4 merged products. These products, are now widely used to define the surface geostrophic currents and beyond that they are used to provide proxies of (sub-)mesoscale transport fronts via the Lyapunov Exponents (LEs). The LEs are being increasingly used in physical, biogeochemical, and ecological applications, ranging from real-time support to field studies to co-localisation of animal tracking with Lagrangian Coherent Structures. In order to better serve the users need, and in collaboration with different laboratories (LOCEAN and CTOH), the LEs and vectors are computed over the 21 year altimeter period and over the global ocean within the SSALTO/DUACS project. This product provides the position, and intensity, and orientation of fronts induced by the mesoscale eddies and underlining part of sub-mesoscale activity. We present here the LEs that will be available on AVISO+ early 2015.

  10. Almost 20 years of Neanderthal palaeogenetics: adaptation, admixture, diversity, demography and extinction.

    PubMed

    Sánchez-Quinto, Federico; Lalueza-Fox, Carles

    2015-01-19

    Nearly two decades since the first retrieval of Neanderthal DNA, recent advances in next-generation sequencing technologies have allowed the generation of high-coverage genomes from two archaic hominins, a Neanderthal and a Denisovan, as well as a complete mitochondrial genome from remains which probably represent early members of the Neanderthal lineage. This genomic information, coupled with diversity exome data from several Neanderthal specimens is shedding new light on evolutionary processes such as the genetic basis of Neanderthal and modern human-specific adaptations-including morphological and behavioural traits-as well as the extent and nature of the admixture events between them. An emerging picture is that Neanderthals had a long-term small population size, lived in small and isolated groups and probably practised inbreeding at times. Deleterious genetic effects associated with these demographic factors could have played a role in their extinction. The analysis of DNA from further remains making use of new large-scale hybridization-capture-based methods as well as of new approaches to discriminate contaminant DNA sequences will provide genetic information in spatial and temporal scales that could help clarify the Neanderthal's-and our very own-evolutionary history.

  11. Hearing aid satisfaction: what does research from the past 20 years say?

    PubMed

    Wong, Lena L N; Hickson, Louise; McPherson, Bradley

    2003-01-01

    Hearing aid satisfaction is a pleasurable emotional experience as an outcome of an evaluation of performance. Many tools have been designed to measure the degree of satisfaction overall, or along the dimensions of cost, appearance, acoustic benefit, comfort, and service. Various studies have used these tools to examine the relationships between satisfaction and other factors. Findings are not always consistent across studies, but in general, hearing aid satisfaction has been found to be related to experience, expectation, personality and attitude, usage, type of hearing aids, sound quality, listening situations, and problems in hearing aid use. Inconsistent findings across studies and difficulties in evaluating the underlying relationships are probably caused by problems with the tools (eg, lack of validity) and the methods used to evaluate relationships (eg, correlation analyses evaluate association and not causal effect). Whether satisfaction changes over time and how service satisfaction contributes to device satisfaction are unclear. It is hoped that this review will help readers understand current satisfaction measures, how various factors affect satisfaction, and how the way satisfaction is measured may be improved to yield more reliable and valid data.

  12. Depression Interventions among Racial and Ethnic Minority Older Adults: A Systematic Review across 20 Years

    PubMed Central

    Fuentes, Dahlia; Aranda, María P.

    2012-01-01

    While there is strong evidence in support of geriatric depression treatments, much less is available with regard to older U.S. racial and ethnic minorities. The objectives of this review are to identify and appraise depression treatment studies tested with samples of U.S. racial and ethnic minority older adults. We include an appraisal of sociocultural adaptations made to the depression treatments in studies meeting our final criteria. Systematic search methods were utilized to identify research published between 1990 and 2010 that describe depression treatment outcomes for older adults by racial/ethnic group, or for samples of older adults that are primarily (i.e., >50%) racial/ethnic minorities. Twenty-three unduplicated articles included older adults and seven met all inclusion criteria. Favorable depression treatment effects were observed for older minorities across five studies based on diverse settings and varying levels of sociocultural adaptations. The effectiveness of depression care remains mixed although collaborative or integrated care shows promise for African Americans and Latinos. The degree to which the findings generalize to non-English-speaking, low acculturated, and low income older persons, and to other older minority groups (i.e., Asian and Pacific Islanders, and American Indian and Alaska Natives) remains unclear. Given the high disease burden among older minorities with depression, it is imperative to provide timely, accessible, and effective depression treatments. Increasing their participation in behavioral health research should be a national priority. PMID:22828202

  13. 20 Years Beyond the Crossroads: The Path to Interprofessional Education at U.S. Dental Schools.

    PubMed

    Palatta, Anthony; Cook, Bryan J; Anderson, Eugene L; Valachovic, Richard W

    2015-08-01

    In 2003, the Institute of Medicine (IOM) called for interprofessional education (IPE) to be adopted by the health professions education community as the pedagogical approach to educating future practitioners for practice in multidisciplinary teams. In dentistry, this call built on points made in the key 1995 IOM report Dental Education at the Crossroads. Currently, IPE and collaborative practice are among the most significant changes to health care education and delivery in the 21st century. This report describes the path that dental education has taken regarding IPE since the first national report on the subject was released in 1995. It also reports the results of a 2014 survey of U.S. dental schools to ascertain their progress in adopting and implementing IPE, as well as perceived obstacles that persist. Of the 63 dental schools, 62 participated, for a response rate of 98%. While over 90% of the respondents reported that their schools offer IPE experiences, only 58.1% had formal university-led and -promoted IPE programs. Formal IPE experiences were more prevalent at public institutions (67.6%, compared with 44% of private institutions). In 2012, a previous study reported that 66% of the IPE experiences offered to dental students were voluntary; today, 69.1% of these activities are required. Interprofessional core competencies occupy four of the top five content areas of IPE programming, providing a framework for schools to implement IPE activities. However, finding the bandwidth within the dental curriculum to accommodate IPE competencies, identifying adequate time in the schedule, providing faculty training, and assessing IPE activities were the most frequently reported challenges. The results of this survey lead to recommendations for academic dental institutions moving through this transitional phase in adopting IPE. PMID:26466391

  14. 20 Years of Air-Water Gas Exchange Observations for Pesticides in the Western Arctic Ocean.

    PubMed

    Jantunen, Liisa M; Wong, Fiona; Gawor, Anya; Kylin, Henrik; Helm, Paul A; Stern, Gary A; Strachan, William M J; Burniston, Deborah A; Bidleman, Terry F

    2015-12-01

    The Arctic has been contaminated by legacy organochlorine pesticides (OCPs) and currently used pesticides (CUPs) through atmospheric transport and oceanic currents. Here we report the time trends and air-water exchange of OCPs and CUPs from research expeditions conducted between 1993 and 2013. Compounds determined in both air and water were trans- and cis-chlordanes (TC, CC), trans- and cis-nonachlors (TN, CN), heptachlor exo-epoxide (HEPX), dieldrin (DIEL), chlorobornanes (ΣCHBs and toxaphene), dacthal (DAC), endosulfans and metabolite endosulfan sulfate (ENDO-I, ENDO-II, and ENDO SUL), chlorothalonil (CHT), chlorpyrifos (CPF), and trifluralin (TFN). Pentachloronitrobenzene (PCNB and quintozene) and its soil metabolite pentachlorothianisole (PCTA) were also found in air. Concentrations of most OCPs declined in surface water, whereas some CUPs increased (ENDO-I, CHT, and TFN) or showed no significant change (CPF and DAC), and most compounds declined in air. Chlordane compound fractions TC/(TC + CC) and TC/(TC + CC + TN) decreased in water and air, while CC/(TC + CC + TN) increased. TN/(TC + CC + TN) also increased in air and slightly, but not significantly, in water. These changes suggest selective removal of more labile TC and/or a shift in chlordane sources. Water-air fugacity ratios indicated net volatilization (FR > 1.0) or near equilibrium (FR not significantly different from 1.0) for most OCPs but net deposition (FR < 1.0) for ΣCHBs. Net deposition was shown for ENDO-I on all expeditions, while the net exchange direction of other CUPs varied. Understanding the processes and current state of air-surface exchange helps to interpret environmental exposure and evaluate the effectiveness of international protocols and provides insights for the environmental fate of new and emerging chemicals. PMID:26196214

  15. Validation of a 20-year forecast of US childhood lead poisoning: Updated prospects for 2010

    SciTech Connect

    Jacobs, David E. . E-mail: dejacobs@starpower.net; Nevin, Rick

    2006-11-15

    We forecast childhood lead poisoning and residential lead paint hazard prevalence for 1990-2010, based on a previously unvalidated model that combines national blood lead data with three different housing data sets. The housing data sets, which describe trends in housing demolition, rehabilitation, window replacement, and lead paint, are the American Housing Survey, the Residential Energy Consumption Survey, and the National Lead Paint Survey. Blood lead data are principally from the National Health and Nutrition Examination Survey. New data now make it possible to validate the midpoint of the forecast time period. For the year 2000, the model predicted 23.3 million pre-1960 housing units with lead paint hazards, compared to an empirical HUD estimate of 20.6 million units. Further, the model predicted 498,000 children with elevated blood lead levels (EBL) in 2000, compared to a CDC empirical estimate of 434,000. The model predictions were well within 95% confidence intervals of empirical estimates for both residential lead paint hazard and blood lead outcome measures. The model shows that window replacement explains a large part of the dramatic reduction in lead poisoning that occurred from 1990 to 2000. Here, the construction of the model is described and updated through 2010 using new data. Further declines in childhood lead poisoning are achievable, but the goal of eliminating children's blood lead levels {>=}10 {mu}g/dL by 2010 is unlikely to be achieved without additional action. A window replacement policy will yield multiple benefits of lead poisoning prevention, increased home energy efficiency, decreased power plant emissions, improved housing affordability, and other previously unrecognized benefits. Finally, combining housing and health data could be applied to forecasting other housing-related diseases and injuries.

  16. Population and genetic outcomes 20 years after reintroducing bobcats (Lynx rufus) to Cumberland Island, Georgia USA

    USGS Publications Warehouse

    Diefenbach, Duane R.; Hansen, Leslie; Bohling, Justin; Miller-Butterworth, Cassandra

    2015-01-01

    In 1988–1989, 32 bobcats Lynx rufus were reintroduced to Cumberland Island (CUIS), Georgia, USA, from which they had previously been extirpated. They were monitored intensively for 3 years immediately post-reintroduction, but no estimation of the size or genetic diversity of the population had been conducted in over 20 years since reintroduction. We returned to CUIS in 2012 to estimate abundance and effective population size of the present-day population, as well as to quantify genetic diversity and inbreeding. We amplified 12 nuclear microsatellite loci from DNA isolated from scats to establish genetic profiles to identify individuals. We used spatially explicit capture–recapture population estimation to estimate abundance. From nine unique genetic profiles, we estimate a population size of 14.4 (SE = 3.052) bobcats, with an effective population size (Ne) of 5–8 breeding individuals. This is consistent with predictions of a population viability analysis conducted at the time of reintroduction, which estimated the population would average 12–13 bobcats after 10 years. We identified several pairs of related bobcats (parent-offspring and full siblings), but ~75% of the pairwise comparisons were typical of unrelated individuals, and only one individual appeared inbred. Despite the small population size and other indications that it has likely experienced a genetic bottleneck, levels of genetic diversity in the CUIS bobcat population remain high compared to other mammalian carnivores. The reintroduction of bobcats to CUIS provides an opportunity to study changes in genetic diversity in an insular population without risk to this common species. Opportunities for natural immigration to the island are limited; therefore, continued monitoring and supplemental bobcat reintroductions could be used to evaluate the effect of different management strategies to maintain genetic diversity and population viability. The successful reintroduction and maintenance of a

  17. 20 Years Beyond the Crossroads: The Path to Interprofessional Education at U.S. Dental Schools.

    PubMed

    Palatta, Anthony; Cook, Bryan J; Anderson, Eugene L; Valachovic, Richard W

    2015-08-01

    In 2003, the Institute of Medicine (IOM) called for interprofessional education (IPE) to be adopted by the health professions education community as the pedagogical approach to educating future practitioners for practice in multidisciplinary teams. In dentistry, this call built on points made in the key 1995 IOM report Dental Education at the Crossroads. Currently, IPE and collaborative practice are among the most significant changes to health care education and delivery in the 21st century. This report describes the path that dental education has taken regarding IPE since the first national report on the subject was released in 1995. It also reports the results of a 2014 survey of U.S. dental schools to ascertain their progress in adopting and implementing IPE, as well as perceived obstacles that persist. Of the 63 dental schools, 62 participated, for a response rate of 98%. While over 90% of the respondents reported that their schools offer IPE experiences, only 58.1% had formal university-led and -promoted IPE programs. Formal IPE experiences were more prevalent at public institutions (67.6%, compared with 44% of private institutions). In 2012, a previous study reported that 66% of the IPE experiences offered to dental students were voluntary; today, 69.1% of these activities are required. Interprofessional core competencies occupy four of the top five content areas of IPE programming, providing a framework for schools to implement IPE activities. However, finding the bandwidth within the dental curriculum to accommodate IPE competencies, identifying adequate time in the schedule, providing faculty training, and assessing IPE activities were the most frequently reported challenges. The results of this survey lead to recommendations for academic dental institutions moving through this transitional phase in adopting IPE.

  18. 20 Years of Air-Water Gas Exchange Observations for Pesticides in the Western Arctic Ocean.

    PubMed

    Jantunen, Liisa M; Wong, Fiona; Gawor, Anya; Kylin, Henrik; Helm, Paul A; Stern, Gary A; Strachan, William M J; Burniston, Deborah A; Bidleman, Terry F

    2015-12-01

    The Arctic has been contaminated by legacy organochlorine pesticides (OCPs) and currently used pesticides (CUPs) through atmospheric transport and oceanic currents. Here we report the time trends and air-water exchange of OCPs and CUPs from research expeditions conducted between 1993 and 2013. Compounds determined in both air and water were trans- and cis-chlordanes (TC, CC), trans- and cis-nonachlors (TN, CN), heptachlor exo-epoxide (HEPX), dieldrin (DIEL), chlorobornanes (ΣCHBs and toxaphene), dacthal (DAC), endosulfans and metabolite endosulfan sulfate (ENDO-I, ENDO-II, and ENDO SUL), chlorothalonil (CHT), chlorpyrifos (CPF), and trifluralin (TFN). Pentachloronitrobenzene (PCNB and quintozene) and its soil metabolite pentachlorothianisole (PCTA) were also found in air. Concentrations of most OCPs declined in surface water, whereas some CUPs increased (ENDO-I, CHT, and TFN) or showed no significant change (CPF and DAC), and most compounds declined in air. Chlordane compound fractions TC/(TC + CC) and TC/(TC + CC + TN) decreased in water and air, while CC/(TC + CC + TN) increased. TN/(TC + CC + TN) also increased in air and slightly, but not significantly, in water. These changes suggest selective removal of more labile TC and/or a shift in chlordane sources. Water-air fugacity ratios indicated net volatilization (FR > 1.0) or near equilibrium (FR not significantly different from 1.0) for most OCPs but net deposition (FR < 1.0) for ΣCHBs. Net deposition was shown for ENDO-I on all expeditions, while the net exchange direction of other CUPs varied. Understanding the processes and current state of air-surface exchange helps to interpret environmental exposure and evaluate the effectiveness of international protocols and provides insights for the environmental fate of new and emerging chemicals.

  19. Psychological and perceived health effects of the Chernobyl disaster: a 20-year review.

    PubMed

    Bromet, Evelyn J; Havenaar, Johan M

    2007-11-01

    The mental health impact of Chernobyl is regarded by many experts as the largest public health problem unleashed by the accident to date. This paper reviews findings reported during the 20-y period after the accident regarding stress-related symptoms, effects on the developing brain, and cognitive and psychological impairments among highly exposed cleanup workers. With respect to stress-related symptoms, the rates of depressive, anxiety (especially post-traumatic stress symptoms), and medically unexplained physical symptoms are two to four times higher in Chernobyl-exposed populations compared to controls, although rates of diagnosable psychiatric disorders do not appear to be elevated. The symptom elevations were found as late as 11 y after the accident. Severity of symptomatology is significantly related to risk perceptions and being diagnosed with a Chernobyl-related health problem. In general, the morbidity patterns are consistent with the psychological impairments documented after other toxic events, such as the atomic bombings of Hiroshima and Nagasaki, the Three Mile Island accident, and Bhopal. With respect to the developing brain of exposed children who were in utero or very young when the accident occurred, the World Health Organization as well as American and Israeli researchers have found no significant associations of radiation exposure with cognitive impairments. Cognitive impairments in highly exposed cleanup workers have been reported by Ukrainian researchers, but these findings have not been independently confirmed. A seminal study found a significant excess death rate from suicide in cleanup workers, suggesting a sizable emotional toll. Given the magnitude and persistence of the adverse mental health effects on the general population, long-term educational and psychosocial interventions should be initiated that target primary care physicians, local researchers, and high risk populations, including participants in ongoing cohort studies. PMID

  20. Trends in conservation research and management in Hawai‘i over the past 20 years

    USGS Publications Warehouse

    Dutra Elliott, Daniela; Fortini, Lucas; Cameron Duffy, David

    2014-01-01

    Hawaiʻi, an archipelago of the most isolated inhabited islands on the planet, faces unique and extreme challenges to its biodiversity. We examined how the conservation community has responded to these challenges and how the responses have changed over time, using twenty years of abstracts from the Hawaiʻi Conservation Conference, a yearly gathering of the majority of scientists, managers and the public in Hawaiʻi. Of the 2145 abstracts considered, 60% percent reported research results; 40.0% reported information on conservation and resource management programmes and institutions (i.e., non-research abstracts). Initially, applied research abstracts predominated, but in recent years the number of basic research abstracts has become similar. Across taxonomic groups, terrestrial plants, mammals and birds were the dominant research subjects, fish, algae and fungi were noticeably less studied relative to their diversity in Hawaiʻi. Bird and fish species studied were mostly native; research on most other taxa was evenly divided between native and non-native species. Topics have oscillated in frequency over the years, but there have been no dramatic trends, with the exception of climate change and Local Ecological Knowledge (LEK). Although there is an increasing trend in LEK and cross-disciplinary studies, the number of related abstracts have remained uncommon through the period, accounting for less than 5.0% of total research abstracts analyzed. Our results offer an oportunity for the conservation community to take a closer look at reported effort to better address key conservation questions for Hawaiʻi.

  1. Psychological and perceived health effects of the Chernobyl disaster: a 20-year review.

    PubMed

    Bromet, Evelyn J; Havenaar, Johan M

    2007-11-01

    The mental health impact of Chernobyl is regarded by many experts as the largest public health problem unleashed by the accident to date. This paper reviews findings reported during the 20-y period after the accident regarding stress-related symptoms, effects on the developing brain, and cognitive and psychological impairments among highly exposed cleanup workers. With respect to stress-related symptoms, the rates of depressive, anxiety (especially post-traumatic stress symptoms), and medically unexplained physical symptoms are two to four times higher in Chernobyl-exposed populations compared to controls, although rates of diagnosable psychiatric disorders do not appear to be elevated. The symptom elevations were found as late as 11 y after the accident. Severity of symptomatology is significantly related to risk perceptions and being diagnosed with a Chernobyl-related health problem. In general, the morbidity patterns are consistent with the psychological impairments documented after other toxic events, such as the atomic bombings of Hiroshima and Nagasaki, the Three Mile Island accident, and Bhopal. With respect to the developing brain of exposed children who were in utero or very young when the accident occurred, the World Health Organization as well as American and Israeli researchers have found no significant associations of radiation exposure with cognitive impairments. Cognitive impairments in highly exposed cleanup workers have been reported by Ukrainian researchers, but these findings have not been independently confirmed. A seminal study found a significant excess death rate from suicide in cleanup workers, suggesting a sizable emotional toll. Given the magnitude and persistence of the adverse mental health effects on the general population, long-term educational and psychosocial interventions should be initiated that target primary care physicians, local researchers, and high risk populations, including participants in ongoing cohort studies.

  2. Holography beyond the horizon and cosmic censorship

    NASA Astrophysics Data System (ADS)

    Levi, Thomas S.; Ross, Simon F.

    2003-08-01

    We investigate the description of the region behind the event horizon in rotating black holes in the AdS conformal field theory correspondence, using the rotating Bañados-Teitelboim-Zanelli black hole as a concrete example. We extend a technique introduced by Kraus, Ooguri, and Shenker, based on analytically continuing amplitudes defined in a Euclidean space, to include rotation. In the rotating case, boundary amplitudes again have two different bulk descriptions, involving either integration only over the regions outside the black holes’ event horizon, or integration over this region and the region between the event horizon and the Cauchy horizon (inner horizon). We argue that generally, the holographic map will relate the field theory to the region bounded by the Cauchy horizons in spacetime. We also argue that these results suggest that the holographic description of black holes will satisfy strong cosmic censorship.

  3. Variable horizon in a peridynamic medium.

    SciTech Connect

    Silling, Stewart Andrew; Littlewood, David John; Seleson, Pablo

    2014-10-01

    A notion of material homogeneity is proposed for peridynamic bodies with vari- able horizon but constant bulk properties. A relation is derived that scales the force state according to the position-dependent horizon while keeping the bulk properties un- changed. Using this scaling relation, if the horizon depends on position, artifacts called ghost forces may arise in a body under homogeneous deformation. These artifacts de- pend on the second derivative of horizon and can be reduced by use of a modified equilibrium equation using a new quantity called the partial stress . Bodies with piece- wise constant horizon can be modeled without ghost forces by using a technique called a splice between the regions. As a limiting case of zero horizon, both partial stress and splice techniques can be used to achieve local-nonlocal coupling. Computational examples, including dynamic fracture in a one-dimensional model with local-nonlocal coupling, illustrate the methods.

  4. Variable horizon in a peridynamic medium

    DOE PAGES

    Silling, Stewart A.; Littlewood, David J.; Seleson, Pablo

    2015-12-10

    Here, a notion of material homogeneity is proposed for peridynamic bodies with variable horizon but constant bulk properties. A relation is derived that scales the force state according to the position-dependent horizon while keeping the bulk properties unchanged. Using this scaling relation, if the horizon depends on position, artifacts called ghost forces may arise in a body under a homogeneous deformation. These artifacts depend on the second derivative of the horizon and can be reduced by employing a modified equilibrium equation using a new quantity called the partial stress. Bodies with piecewise constant horizon can be modeled without ghost forcesmore » by using a simpler technique called a splice. As a limiting case of zero horizon, both the partial stress and splice techniques can be used to achieve local-nonlocal coupling. Computational examples, including dynamic fracture in a one-dimensional model with local-nonlocal coupling, illustrate the methods.« less

  5. Variable horizon in a peridynamic medium

    SciTech Connect

    Silling, Stewart A.; Littlewood, David J.; Seleson, Pablo

    2015-12-10

    Here, a notion of material homogeneity is proposed for peridynamic bodies with variable horizon but constant bulk properties. A relation is derived that scales the force state according to the position-dependent horizon while keeping the bulk properties unchanged. Using this scaling relation, if the horizon depends on position, artifacts called ghost forces may arise in a body under a homogeneous deformation. These artifacts depend on the second derivative of the horizon and can be reduced by employing a modified equilibrium equation using a new quantity called the partial stress. Bodies with piecewise constant horizon can be modeled without ghost forces by using a simpler technique called a splice. As a limiting case of zero horizon, both the partial stress and splice techniques can be used to achieve local-nonlocal coupling. Computational examples, including dynamic fracture in a one-dimensional model with local-nonlocal coupling, illustrate the methods.

  6. The XIOM: 20 years of a regional coastal observatory in the Spanish Catalan coast

    NASA Astrophysics Data System (ADS)

    Bolaños, R.; Jorda, G.; Cateura, J.; Lopez, J.; Puigdefabregas, J.; Gomez, J.; Espino, M.

    2009-05-01

    it presents a seasonal intensification in winter where velocities can reach higher values. Over the shelf, little work has been previously done over long time series. The measurements obtained allowed the identification of the relative influence of winds, Ebro river outflow and open sea dynamics on the shelf dynamics. An oil spill drift forecasting system has also been developed in which measurements will be used for the short forecast of oil transport. The XIOM is still growing and in a short term period meteorological buoys with current meters will be deployed and scalar buoys will be replaced by directional ones.

  7. Food and water security scenarios for East Africa over next 20 years

    NASA Astrophysics Data System (ADS)

    Shukla, S.; Funk, C. C.; Verdin, J. P.; Peters-Lidard, C. D.

    2013-12-01

    Broad areas of East Africa face chronic water and agricultural insecurity. Over the last decade, the region has experienced frequent drought events leading to food security emergencies and even famine in Somalia in 2011. The impact of these drought events, associated with recent declines in rainfall during major growing seasons, has been particularly severe due to the high vulnerability of subsistence agricultural and pastoralist livelihoods, rapid population growth, and the limited availability of resources for agricultural development and climate change adaptation. The Famine Early Warning Systems Network (FEWS NET) is a United States Agency for International Development (USAID) funded activity that brings together international, regional and national partners to provide timely and rigorous early warning and food security information in Africa and other regions of the developing world. To assist USAID with planning agricultural development strategies over the next ten years in East Africa, FEWS NET is partnering with climate scientists and adaptation specialists at regional institutions to study and assess future changes in precipitation and temperature in light of global climate change, natural climate variability, and their related impacts on agricultural and water security in the region. The overarching objective of this study is to provide future scenarios of food and water security (as estimated by trends in soil moisture, evapotranspiration, and runoff) for East Africa. We do so by following two approaches: Constructed Analogs and the Composite Delta Method. In the first approach we downscaled climate projections (precipitation and temperature projections) of long-term Coupled Model Intercomparison Project Phase-5 (CMIP5) experiments over (a) historical (1850-2005) and (b) Representative Concentration Pathway (RCP) 8.5 (2006-2030) periods. Current climate is characterized by two ENSO modes, the intensity of the Pacific Decadal Oscillation, and the strength

  8. Postabortion Care: 20 Years of Strong Evidence on Emergency Treatment, Family Planning, and Other Programming Components

    PubMed Central

    Huber, Douglas; Curtis, Carolyn; Irani, Laili; Pappa, Sara; Arrington, Lauren

    2016-01-01

    ABSTRACT Worldwide 75 million women need postabortion care (PAC) services each year following safe or unsafe induced abortions and miscarriages. We reviewed more than 550 studies on PAC published between 1994 and 2013 in the peer-reviewed and gray literature, covering emergency treatment, postabortion family planning, organization of services, and related topics that impact practices and health outcomes, particularly in the Global South. In this article, we present findings from studies with strong evidence that have major implications for programs and practice. For example, vacuum aspiration reduced morbidity, costs, and time in comparison to sharp curettage. Misoprostol 400 mcg sublingually or 600 mcg orally achieved 89% to 99% complete evacuation rates within 2 weeks in multiple studies and was comparable in effectiveness, safety, and acceptability to manual vacuum aspiration. Misoprostol was safely introduced in several PAC programs through mid-level providers, extending services to secondary hospitals and primary health centers. In multiple studies, postabortion family planning uptake before discharge increased by 30–70 percentage points within 1–3 years of strengthening postabortion family planning services; in some cases, increases up to 60 percentage points in 4 months were achieved. Immediate postabortion contraceptive acceptance increased on average from 32% before the interventions to 69% post-intervention. Several studies found that women receiving immediate postabortion intrauterine devices and implants had fewer unintended pregnancies and repeat abortions than those who were offered delayed insertions. Postabortion family planning is endorsed by the professional organizations of obstetricians/gynecologists, midwives, and nurses as a standard of practice; major donors agree, and governments should be encouraged to provide universal access to postabortion family planning. Important program recommendations include offering all postabortion women

  9. Postabortion Care: 20 Years of Strong Evidence on Emergency Treatment, Family Planning, and Other Programming Components.

    PubMed

    Huber, Douglas; Curtis, Carolyn; Irani, Laili; Pappa, Sara; Arrington, Lauren

    2016-09-28

    Worldwide 75 million women need postabortion care (PAC) services each year following safe or unsafe induced abortions and miscarriages. We reviewed more than 550 studies on PAC published between 1994 and 2013 in the peer-reviewed and gray literature, covering emergency treatment, postabortion family planning, organization of services, and related topics that impact practices and health outcomes, particularly in the Global South. In this article, we present findings from studies with strong evidence that have major implications for programs and practice. For example, vacuum aspiration reduced morbidity, costs, and time in comparison to sharp curettage. Misoprostol 400 mcg sublingually or 600 mcg orally achieved 89% to 99% complete evacuation rates within 2 weeks in multiple studies and was comparable in effectiveness, safety, and acceptability to manual vacuum aspiration. Misoprostol was safely introduced in several PAC programs through mid-level providers, extending services to secondary hospitals and primary health centers. In multiple studies, postabortion family planning uptake before discharge increased by 30-70 percentage points within 1-3 years of strengthening postabortion family planning services; in some cases, increases up to 60 percentage points in 4 months were achieved. Immediate postabortion contraceptive acceptance increased on average from 32% before the interventions to 69% post-intervention. Several studies found that women receiving immediate postabortion intrauterine devices and implants had fewer unintended pregnancies and repeat abortions than those who were offered delayed insertions. Postabortion family planning is endorsed by the professional organizations of obstetricians/gynecologists, midwives, and nurses as a standard of practice; major donors agree, and governments should be encouraged to provide universal access to postabortion family planning. Important program recommendations include offering all postabortion women family planning

  10. Summary of Almost 20 Years of Storm Overflight Electric Field, Conductivity, Flash Rate, and Current Statistics

    NASA Technical Reports Server (NTRS)

    Blakeslee, Richard J.; Mach, Douglas M.; Bateman, Monte J.; Bailey, Jeffrey C.

    2011-01-01

    We present total conduction (Wilson) currents for more than 1000 high-altitude aircraft overflights of electrified clouds acquired over nearly two decades. The overflights include a wide geographical sample of storms over land and ocean, with and without lightning, and with positive (i.e., upward-directed) and negative current. Peak electric field, with lightning transients removed, ranged from -1.0 kV/m to 16. kV/m, with mean (median) of 0.9 kV/m (0.29 kV/m). Total conductivity at flight altitude ranged from 0.6 pS/m to 3.6 pS/m, with mean and median of 2.2 pS/m. Peak current densities ranged from -2.0 nA m(exp -2) to 33.0 nA m(exp -2) with mean (median) of 1.9 nA m(exp -2) (0.6 nA m(exp -2)). Total upward current flow from storms in our dataset ranged from -1.3 to 9.4 A. The mean current for storms with lightning is 1.7 A over ocean and 1.0 A over land. The mean current for electrified shower clouds (i.e. electrified storms without lightning) is 0.41 A for ocean and 0.13 A for land. About 78% (43%) of the land (ocean) storms have detectable lightning. Land storms have 2.8 times the mean flash rate as ocean storms (2.2 versus 0.8 flashes min-1, respectively). Approximately 7% of the overflights had negative current. The mean and median currents for positive (negative) polarity storms are 1.0 and 0.35 A (-0.30 and -0.26 A). We found no regional or latitudinal-based patterns in our storm currents, nor support for simple scaling laws between cloud top height and lightning flash rate.

  11. Cochlear implantation in chronic otitis media and previous middle ear surgery: 20 years of experience.

    PubMed

    Vincenti, V; Pasanisi, E; Bacciu, A; Bacciu, S; Zini, C

    2014-08-01

    Cochlear implantation in the setting of chronic otitis media or previous middle ear surgery poses several problems for the surgeon: possible spread of infection to the cochlea and the subarachnoid spaces with consequent meningitis, risk of electrode array extrusion and possible recurrence of the original disease. Several surgical strategies have been proposed to overcome these problems. In the present study, clinical and functional results of cochlear implantation in 26 patients with chronic otitis media (8 cases) or previous middle ear surgery (18 cases) in the ear most suitable for implantation were retrospectively reviewed. Among the 8 patients with chronic otitis media, in 7 cases a subtotal petrosectomy associated with external auditory canal closure and mastoid and Eustachian tube obliteration was performed, while in the remaining patient cochlear implantation was done 6 months after a myringoplasty. The only complication observed was a reperforation of the tympanic membrane in this latter patient. Among the 18 patients with previous middle ear surgery, 2 had undergone intact canal wall tympanomastoidectomy and were implanted utilising the previous surgical approach. In the remaining 16 patients who had a radical cavity, an open technique was maintained in 3 cases; a cavity revision associated to external auditory canal closure, Eustachian tube and mastoid obliteration was performed in 12 patients, while in one case a middle cranial fossa approach was utilised. Two of the 3 patients in whom an open technique was maintained have experienced electrode array extrusion. The only complication observed in the remaining patients was the breakdown of the external auditory canal closure in one case. No problems were noted in patients who had undergone intact canal wall tympanomastoidectomy as well as in the subject implanted via the middle cranial fossa approach. All patients achieved and maintained good hearing performance over time. Subtotal petrosectomy associated

  12. Postabortion Care: 20 Years of Strong Evidence on Emergency Treatment, Family Planning, and Other Programming Components.

    PubMed

    Huber, Douglas; Curtis, Carolyn; Irani, Laili; Pappa, Sara; Arrington, Lauren

    2016-09-28

    Worldwide 75 million women need postabortion care (PAC) services each year following safe or unsafe induced abortions and miscarriages. We reviewed more than 550 studies on PAC published between 1994 and 2013 in the peer-reviewed and gray literature, covering emergency treatment, postabortion family planning, organization of services, and related topics that impact practices and health outcomes, particularly in the Global South. In this article, we present findings from studies with strong evidence that have major implications for programs and practice. For example, vacuum aspiration reduced morbidity, costs, and time in comparison to sharp curettage. Misoprostol 400 mcg sublingually or 600 mcg orally achieved 89% to 99% complete evacuation rates within 2 weeks in multiple studies and was comparable in effectiveness, safety, and acceptability to manual vacuum aspiration. Misoprostol was safely introduced in several PAC programs through mid-level providers, extending services to secondary hospitals and primary health centers. In multiple studies, postabortion family planning uptake before discharge increased by 30-70 percentage points within 1-3 years of strengthening postabortion family planning services; in some cases, increases up to 60 percentage points in 4 months were achieved. Immediate postabortion contraceptive acceptance increased on average from 32% before the interventions to 69% post-intervention. Several studies found that women receiving immediate postabortion intrauterine devices and implants had fewer unintended pregnancies and repeat abortions than those who were offered delayed insertions. Postabortion family planning is endorsed by the professional organizations of obstetricians/gynecologists, midwives, and nurses as a standard of practice; major donors agree, and governments should be encouraged to provide universal access to postabortion family planning. Important program recommendations include offering all postabortion women family planning

  13. Theory underlying the peripheral vision horizon device

    NASA Technical Reports Server (NTRS)

    Money, K. E.

    1984-01-01

    Peripheral Vision Horizon Device (PVHD) theory states that the likelihood of pilot disorientation in flight is reduced by providing an artificial horizon that provides orientation information to peripheral vision. In considering the validity of the theory, three areas are explored: the use of an artificial horizon device over some other flight instrument; the use of peripheral vision over foveal vision; and the evidence that peripheral vision is well suited to the processing of orientation information.

  14. 20 years of cosmic muons research performed in IFIN-HH

    SciTech Connect

    Mitrica, Bogdan

    2012-11-20

    During the last two decades a modern direction in particle physics research has been developed in IFIN-HH Bucharest, Romania. The history started with the WILLI detector built in IFIN-HH Bucharest in collaboration with KIT Karlsruhe (formerly Forschungszentrum Karlsruhe). The detector was designed for measurements of the low energy muon charge ratio (< 1GeV) based on a delayed coincidence method, measuring the decay time of the muons stopped in the detector: the positive muons decay freely, but the negative muons are captured in the atom thus creating muonic atoms and decay depending on the nature of the host atom. In a first configuration, the WILLI detector was placed in a fixed position for measuring vertical muons. Further WILLI has been transformed in a rotatable device which allows directional measurements of muon charge ratio and muon flux. The results exhibit a pronounced azimuthal asymmetry (East-West effect) due to the different in fluence of the geomagnetic field on the trajectories of positive and negative muons in air. In parallel, flux measurement, taking into account muon events with nergies > 0.4GeV, show a diurnal modulation of the muon flux. The analysis of the muon events for energies < 0.6GeV reveals an aperiodic variation of the muon flux. A new detection system performing coincidence measurements between the WILLI calorimeter and a small array of 12 scintillators plates has been installed in IFIN-HH starting from the autumn of 2010. The aim of the system is to investigate muon charge ratio from individual EAS by using the mini-array as trigger for the WILLI calorimeter. Such experimental studies could provide detailed information on hadronic interaction models and primary cosmic ray composition at energies around 10{sup 15}eV. Simulation studies and preliminary experimental tests, regarding the performances of the mini-array, have been performed using H and Fe primaries, with energies in a range 10{sup 13}eV - 10{sup 15}eV. The results show

  15. Horizons of semiclassical black holes are cold

    NASA Astrophysics Data System (ADS)

    Brustein, Ram; Medved, A. J. M.

    2014-06-01

    We calculate, using our recently proposed semiclassical framework, the quantum state of the Hawking pairs that are produced during the evaporation of a black hole (BH). Our framework adheres to the standard rules of quantum mechanics and incorporates the quantum fluctuations of the collapsing shell spacetime in Hawking's original calculation, while accounting for back-reaction effects. We argue that the negative-energy Hawking modes need to be regularly integrated out; and so these are effectively subsumed by the BH and, as a result, the number of coherent negative-energy modes N coh at any given time is parametrically smaller than the total number of the Hawking particles N total emitted during the lifetime of the BH. We find that N coh is determined by the width of the BH wavefunction and scales as the square root of the BH entropy. We also find that the coherent negative-energy modes are strongly entangled with their positive-energy partners. Previously, we have found that N coh is also the number of coherent outgoing particles and that information can be continually transferred to the outgoing radiation at a rate set by N coh . Our current results show that, while the BH is semiclassical, information can be released without jeopardizing the nearly maximal inside-out entanglement and imply that the state of matter near the horizon is approximately the vacuum. The BH firewall proposal, on the other hand, is that the state of matter near the horizon deviates substantially from the vacuum, starting at the Page time. We find that, under the usual assumptions for justifying the formation of a firewall, one does indeed form at the Page time. However, the possible loophole lies in the implicit assumption that the number of strongly entangled pairs can be of the same order of N total .

  16. Comparing 20 years of precipitation estimates from different sources over the world ocean

    NASA Astrophysics Data System (ADS)

    Béranger, Karine; Barnier, Bernard; Gulev, Sergei; Crépon, Michel

    2006-06-01

    over periods they have in common. First, six among the ten data sets (SOC, UWM, ECMWF, NCEP, MSU and CMAP) are compared over their common period of 14 years, from 1980 to 1993. Then CMAP is compared to GPCP over the 1988 1995 period and to HOAPS over the 1992 1998 period. Usual diagnostics, like comparison of the precipitation patterns exhibited in the annual climatological means of zonal averages and global budget, are used to investigate differences between the various precipitation fields. In addition, precipitation rates are spatially integrated over 16 regional boxes, which are representative of the major ocean gyres or large-scale ocean circulation patterns. Seasonal and inter-annual variations are studied over these boxes in terms of time series anomalies or correlation coefficients. The analysis attempts to characterise differences and biases according to the original source of data (i.e. in situ or satellite, etc.). Qualitative agreement can be observed in all climatologies, which reproduce the major characteristics of the precipitation patterns over the oceans. However, great disagreements occur in terms of quantitative values and regional patterns, especially in regions of high precipitation. However, a better agreement is generally found in the northern hemisphere. The most significant differences, observed between data sets in the mean seasonal cycles and interannual variations, are discussed. A major result of the paper, which was not expected a priori, is that differences between data sets are much more dependent upon the ocean region that is considered than upon the origin of the data sets (in situ vs satellite vs model, etc.). Our analysis did not provide enough objective elements, which would allow us to clearly recommend a given data set as reference or best estimate. However, composite data sets (GPCP, and especially CMAP), because they never appeared to be really “off” when compared to other data sets, may represent the best recent data set

  17. Horizon entropy with loop quantum gravity methods

    NASA Astrophysics Data System (ADS)

    Pranzetti, Daniele; Sahlmann, Hanno

    2015-06-01

    We show that the spherically symmetric isolated horizon can be described in terms of an SU (2) connection and an su (2)-valued one-form, obeying certain constraints. The horizon symplectic structure is precisely the one of 3d gravity in a first order formulation. We quantize the horizon degrees of freedom in the framework of loop quantum gravity, with methods recently developed for 3d gravity with non-vanishing cosmological constant. Bulk excitations ending on the horizon act very similarly to particles in 3d gravity. The Bekenstein-Hawking law is recovered in the limit of imaginary Barbero-Immirzi parameter. Alternative methods of quantization are also discussed.

  18. Spectroscopy of a weakly isolated horizon

    NASA Astrophysics Data System (ADS)

    Chen, Ge-Rui; Huang, Yong-Chang

    2016-06-01

    The spectroscopy of a weakly isolated horizon has been investigated. We obtain an equally spaced entropy spectrum with its quantum equal to the one given by Bekenstein (Phys Rev D 7:2333, 1973). We demonstrate that the quantization of entropy and area is a generic property of horizons which exists in a wide class of spacetimes admitting weakly isolated horizons. Our method based on the tunneling method also indicates that the entropy quantum of black hole horizons is closely related to Hawking temperature.

  19. Apparent horizon in fluid-gravity duality

    SciTech Connect

    Booth, Ivan; Heller, Michal P.; Plewa, Grzegorz; Spalinski, Michal

    2011-05-15

    This article develops a computational framework for determining the location of boundary-covariant apparent horizons in the geometry of conformal fluid-gravity duality in arbitrary dimensions. In particular, it is shown up to second order and conjectured to hold to all orders in the gradient expansion that there is a unique apparent horizon which is covariantly expressible in terms of fluid velocity, temperature, and boundary metric. This leads to the first explicit example of an entropy current defined by an apparent horizon and opens the possibility that in the near-equilibrium regime there is preferred foliation of apparent horizons for black holes in asymptotically anti-de Sitter spacetimes.

  20. A MIP Model for Rolling Horizon Surgery Scheduling.

    PubMed

    Luo, Li; Luo, Yong; You, Yang; Cheng, Yuanjun; Shi, Yingkang; Gong, Renrong

    2016-05-01

    Most surgery scheduling is done 1 day in advance. Caused by lack of overall planning, this scheduling scheme often results in unbalanced occupancy time of the operating rooms. So we put forward a rolling horizon mixed integer programming model for the scheduling. Rolling horizon scheduling refers to a scheduling scheme in which cyclic surgical requests are taken into account. Surgical requests are updated daily. The completed surgeries are eliminated, and new surgeries are added to the scheduling list. Considering day-to-day demand for surgery, we develop a non-rolling scheduling model (NRSM) and a rolling horizon scheduling model (RSM). By comparing the two, we find that the quality of surgery scheduling is significantly influenced by the variation in demand from day to day. A rolling horizon scheduling will enable a more flexible planning of the pool of surgeries that have not been scheduled into this main blocks, and hence minimize the idle time of operating rooms. The strategy of the RSM helps balance the occupancy time among operating rooms. Using surgical data from five departments of the West China Hospital (WCH), we generate surgical demands randomly to compare the NRSM and the RSM. The results show the operating rooms' average utilization rate using RSM is significantly higher than when applying NRSM.

  1. Priority Questions and Horizon Scanning for Conservation: A Comparative Study.

    PubMed

    Kark, Salit; Sutherland, William J; Shanas, Uri; Klass, Keren; Achisar, Hila; Dayan, Tamar; Gavrieli, Yael; Justo-Hanani, Ronit; Mandelik, Yael; Orion, Nir; Pargament, David; Portman, Michelle; Reisman-Berman, Orna; Safriel, Uriel N; Schaffer, Gad; Steiner, Noa; Tauber, Israel; Levin, Noam

    2016-01-01

    Several projects aimed at identifying priority issues for conservation with high relevance to policy have recently been completed in several countries. Two major types of projects have been undertaken, aimed at identifying (i) policy-relevant questions most imperative to conservation and (ii) horizon scanning topics, defined as emerging issues that are expected to have substantial implications for biodiversity conservation and policy in the future. Here, we provide the first overview of the outcomes of biodiversity and conservation-oriented projects recently completed around the world using this framework. We also include the results of the first questions and horizon scanning project completed for a Mediterranean country. Overall, the outcomes of the different projects undertaken (at the global scale, in the UK, US, Canada, Switzerland and in Israel) were strongly correlated in terms of the proportion of questions and/or horizon scanning topics selected when comparing different topic areas. However, some major differences were found across regions. There was large variation among regions in the percentage of proactive (i.e. action and response oriented) versus descriptive (non-response oriented) priority questions and in the emphasis given to socio-political issues. Substantial differences were also found when comparing outcomes of priority questions versus horizon scanning projects undertaken for the same region. For example, issues related to climate change, human demography and marine ecosystems received higher priority as horizon scanning topics, while ecosystem services were more emphasized as current priority questions. We suggest that future initiatives aimed at identifying priority conservation questions and horizon scanning topics should allow simultaneous identification of both current and future priority issues, as presented here for the first time. We propose that further emphasis on social-political issues should be explicitly integrated into future

  2. Priority Questions and Horizon Scanning for Conservation: A Comparative Study

    PubMed Central

    Kark, Salit; Sutherland, William J.; Shanas, Uri; Klass, Keren; Achisar, Hila; Dayan, Tamar; Gavrieli, Yael; Justo-Hanani, Ronit; Mandelik, Yael; Orion, Nir; Pargament, David; Portman, Michelle; Reisman-Berman, Orna; Safriel, Uriel N.; Schaffer, Gad; Steiner, Noa; Tauber, Israel; Levin, Noam

    2016-01-01

    Several projects aimed at identifying priority issues for conservation with high relevance to policy have recently been completed in several countries. Two major types of projects have been undertaken, aimed at identifying (i) policy-relevant questions most imperative to conservation and (ii) horizon scanning topics, defined as emerging issues that are expected to have substantial implications for biodiversity conservation and policy in the future. Here, we provide the first overview of the outcomes of biodiversity and conservation-oriented projects recently completed around the world using this framework. We also include the results of the first questions and horizon scanning project completed for a Mediterranean country. Overall, the outcomes of the different projects undertaken (at the global scale, in the UK, US, Canada, Switzerland and in Israel) were strongly correlated in terms of the proportion of questions and/or horizon scanning topics selected when comparing different topic areas. However, some major differences were found across regions. There was large variation among regions in the percentage of proactive (i.e. action and response oriented) versus descriptive (non-response oriented) priority questions and in the emphasis given to socio-political issues. Substantial differences were also found when comparing outcomes of priority questions versus horizon scanning projects undertaken for the same region. For example, issues related to climate change, human demography and marine ecosystems received higher priority as horizon scanning topics, while ecosystem services were more emphasized as current priority questions. We suggest that future initiatives aimed at identifying priority conservation questions and horizon scanning topics should allow simultaneous identification of both current and future priority issues, as presented here for the first time. We propose that further emphasis on social-political issues should be explicitly integrated into future

  3. Priority Questions and Horizon Scanning for Conservation: A Comparative Study.

    PubMed

    Kark, Salit; Sutherland, William J; Shanas, Uri; Klass, Keren; Achisar, Hila; Dayan, Tamar; Gavrieli, Yael; Justo-Hanani, Ronit; Mandelik, Yael; Orion, Nir; Pargament, David; Portman, Michelle; Reisman-Berman, Orna; Safriel, Uriel N; Schaffer, Gad; Steiner, Noa; Tauber, Israel; Levin, Noam

    2016-01-01

    Several projects aimed at identifying priority issues for conservation with high relevance to policy have recently been completed in several countries. Two major types of projects have been undertaken, aimed at identifying (i) policy-relevant questions most imperative to conservation and (ii) horizon scanning topics, defined as emerging issues that are expected to have substantial implications for biodiversity conservation and policy in the future. Here, we provide the first overview of the outcomes of biodiversity and conservation-oriented projects recently completed around the world using this framework. We also include the results of the first questions and horizon scanning project completed for a Mediterranean country. Overall, the outcomes of the different projects undertaken (at the global scale, in the UK, US, Canada, Switzerland and in Israel) were strongly correlated in terms of the proportion of questions and/or horizon scanning topics selected when comparing different topic areas. However, some major differences were found across regions. There was large variation among regions in the percentage of proactive (i.e. action and response oriented) versus descriptive (non-response oriented) priority questions and in the emphasis given to socio-political issues. Substantial differences were also found when comparing outcomes of priority questions versus horizon scanning projects undertaken for the same region. For example, issues related to climate change, human demography and marine ecosystems received higher priority as horizon scanning topics, while ecosystem services were more emphasized as current priority questions. We suggest that future initiatives aimed at identifying priority conservation questions and horizon scanning topics should allow simultaneous identification of both current and future priority issues, as presented here for the first time. We propose that further emphasis on social-political issues should be explicitly integrated into future

  4. Seasonal cycle of volume transport through Kerama Gap revealed by a 20-year global HYbrid Coordinate Ocean Model reanalysis

    NASA Astrophysics Data System (ADS)

    Yu, Zhitao; Metzger, E. Joseph; Thoppil, Prasad; Hurlburt, Harley E.; Zamudio, Luis; Smedstad, Ole Martin; Na, Hanna; Nakamura, Hirohiko; Park, Jae-Hun

    2015-12-01

    The temporal variability of volume transport from the North Pacific Ocean to the East China Sea (ECS) through Kerama Gap (between Okinawa Island and Miyakojima Island - a part of Ryukyu Islands Arc) is investigated using a 20-year global HYbrid Coordinate Ocean Model (HYCOM) reanalysis with the Navy Coupled Ocean Data Assimilation from 1993 to 2012. The HYCOM mean transport is 2.1 Sv (positive into the ECS, 1 Sv = 106 m3/s) from June 2009 to June 2011, in good agreement with the observed 2.0 Sv transport during the same period. This is similar to the 20-year mean Kerama Gap transport of 1.95 ± 4.0 Sv. The 20-year monthly mean volume transport (transport seasonal cycle) is maximum in October (3.0 Sv) and minimum in November (0.5 Sv). The annual variation component (345-400 days), mesoscale eddy component (70-345 days), and Kuroshio meander component (< 70 days) are separated to determine their contributions to the transport seasonal cycle. The annual variation component has a close relation with the local wind field and increases (decreases) transport into the ECS through Kerama Gap in summer (winter). Most of the variations in the transport seasonal cycle come from the mesoscale eddy component. The impinging mesoscale eddies increase the transport into the ECS during January, February, May, and October, and decrease it in March, April, November, and December, but have little effect in summer (June-September). The Kuroshio meander components cause smaller transport variations in summer than in winter.

  5. A case report of Gordon's syndrome in a 20-year-old male with free medical family history.

    PubMed

    Kostakis, Ioannis D; Tsoukalas, Nikolaos G; Aravantinos, Dionysios C; Gkizis, Ilias G; Cholidou, Kyriaki G; Papadopoulos, Dimitris P

    2013-01-01

    Gordon's syndrome is a rare autosomal dominant disease that manifests in childhood. It is characterized by hypertension, hyperkalemic hyperchloremic metabolic acidosis, low renin and usually normal aldosterone levels, and it is sensitive to thiazide diuretics. A 20-year-old male with a history of diagnosed Gordon's syndrome was referred to a nephrology clinic for evaluation. The patient, who was under treatment with hydrochlorothiazide, had been diagnosed with Gordon's syndrome at the age of 11, when he presented hypertension and episodes of hyperkalemic hyperchloremic metabolic acidosis. However, none of his relatives had been diagnosed with this syndrome. Therefore, we assume that our patient might be a case of de novo gene mutation.

  6. A 20 year review of punishment and alternative methods to treat problem behaviors in developmentally delayed persons.

    PubMed

    Matson, J L; Taras, M E

    1989-01-01

    Relevant journals were reviewed (n = 23) for a 20 year period (1967 to 1987) to assess the status of treatments for severe behavior problems of developmentally delayed persons. A hand search of journals was made; 382 studies were identified. Procedures were analyzed by problem behaviors treated, side effects reported, whether the procedure involved painful stimuli, nonpainful stimuli, food satiation, positive procedures, extinction or combinations of methods. The number of studies reported yearly was also plotted. The implication of these data for federal and state policy makers and for treatment programs dealing with difficult to treat clients is discussed. PMID:2648505

  7. Neuropsychological sequelae of Wernicke's encephalopathy in a 20-year-old woman: selective impairment of a frontal memory system.

    PubMed

    Parkin, A J; Dunn, J C; Lee, C; O'Hara, P F; Nussbaum, L

    1993-01-01

    This article reports the neuropsychological sequelae of Wernicke's Encephalopathy in a 20-year-old woman. After amelioration of acute symptoms, the patient showed a range of cognitive impairments the most marked of which was a severe impairment on free recall tasks involving both verbal and nonverbal material. In contrast, recognition memory appeared remarkably well preserved. Some evidence of frontal lobe and general intellectual impairment was also noted. The case is discussed in terms of the pathophysiology of Wernicke-Korsakoff Syndrome, criteria for its diagnosis, and the multicomponent nature of memory deficits.

  8. Subjective Well-Being In Later Life: 20 years after the Butterworths monograph series on individual and population aging.

    PubMed

    Stones, Michael; Kozma, Albert; McNeil, Kevin; Worobetz, Sarah

    2011-09-01

    This article discusses developments in theory and research on happiness two decades after publication of Psychological Well-Being in Later Life (Butterworths, 1991) by Albert Kozma, Michael Stones, and Kevin McNeil. Major empirical advances include new knowledge about contributions to happiness resulting from genetically related effects and personality. Personality traits have stronger relationships with happiness than was apparent 20 years ago and contribute to covariance between happiness and some of its predictors. Evolving emphases in research include the ways in which genetically related effects influence how people shape, and react to, their environment.

  9. 20 Years and Counting

    ERIC Educational Resources Information Center

    Kuzyk, Raya

    2008-01-01

    In commemoration of the Librarian of the Year Award's 20th anniversary, this article presents brief vignettes on all 19 of the title holders. When "Library Journal" named them Librarians of the Year, these inimitable 19 (for the 20th, Norma Blake, see EJ788676) had singled themselves out as risk takers, visionaries, bulldogs, pragmatists,…

  10. COBE: 20 Years Ago

    NASA Video Gallery

    NASA's Cosmic Background Explorer (COBE) satellite rocketed into Earth orbit on Nov. 18, 1989, and quickly revolutionized our understanding of the early cosmos. This archival video was reissued by ...

  11. 20 Years of RECONS

    NASA Astrophysics Data System (ADS)

    Henry, Todd J.; RECONS

    2014-01-01

    RECONS (REsearch Consortium On Nearby Stars, www.recons.org) turns 20 in 2014, so we take this opportunity to review some of the highlights of the RECONS effort over the past two decades. Through comprehensive searches for new nearby stars, as well as characterization of the stars and exploration of their environments, the RECONS team has made significant contributions to our understanding of the solar neighborhood, and of our own place in the Universe. Here we highlight results detailed in more than 30 papers in The Solar Neighborhood series published in The Astronomical Journal, including: (1) a census indicating that at least 75% of all stars are red dwarfs, which have more real estate available for habitable planets than any other type of star, (2) more than 300 new stellar systems with accurate trigonometric parallaxes placing them within 25 pc, including 12 of the nearest 100 systems, (3) thousands of additional nearby star candidates identified through traditional proper motion searches and novel photometric searches for stars exhibiting minimal proper motions, (4) increases of more than 20% in the nearest white dwarf and cool subdwarf populations, (5) discovery of the nearest star, AP Col, younger than 100 million years, (6) knowledge that more than half of stellar systems contain only one star, dominated by the red dwarf multiplicity rate of only about 30%, (7) definition of the smallest main sequence star, with a radius only 9% that of the Sun (smaller than Jupiter) and a temperature of 2100K, and (8) a revelation that the smallest stars are rarely orbited by giant planets, including the elimination of planets down to half a Jupiter mass orbiting Proxima Centauri. As RECONS enters its third decade, we continue our reconnaissance of the solar neighborhood via a comprehensive survey to understand the nature of star formation by determining accurate luminosity and mass functions for the nearest stars. In addition, we are taking an inventory of nearby planets, including an astrometric search of several hundred of the nearest red dwarfs for planetary systems. This effort is supported by the NSF through grants AST-0908402 and AST-1109445, and via observations made possible by the SMARTS Consortium.

  12. 20 years of toxicology.

    PubMed Central

    Fisher, B E

    1998-01-01

    With over 80,000 chemicals being used in commerce worldwide, it is important to identify the human health effects of these chemicals and the levels of exposure at which they are harmful to humans. In order to address this need, the National Toxicology Program (NTP) was established in 1978; since then, the NTP has become the world's leader in designing, conducting, and interpreting various types of toxicity assays. PMID:9755149

  13. Water Erosion in Relation with Soil Management System and Crop Sequence during 20 Years on an Inceptisol in South Brazil

    NASA Astrophysics Data System (ADS)

    Bertol, I.; Schick, J.; Barbosa, F. T.; Paz-Ferreiro, J.; Flores, M. T.; Paz González, A.

    2012-04-01

    Soil erosion still remains persistent at the world scale, even if big efforts have been done to control and reduce it, mainly using soil crop residues to protect soil surface. Although in South Brazil the main management system for most crops is no tillage and direct drilling, water erosion prevails as the most important soil erosion type, which is due both, to the high erosivity and the evenly distribution of rainfall over the year. Moreover, some crops are still grown under soil tillage systems consisting of ploughing, harrowing and less frequently chiselling. Starting 1992, a field experiment under natural rainfall has been conducted on an Inceptisol located in Lages, Santa Catarina State, Brazil, which objective was to assess rainfall water erosion. Two soil cover conditions and four soil management systems were studied: I) a crop rotation, which included oats (Avena strigosa), soybean (Glycine max), common vetch (Vicia sativa), maize (Zea mays), fodder radish (Raphanus sativus) and common bean (Phaseolus vulgaris) under the following soil management types: 1) ploughing plus two levelling operations (CT), chiselling plus levelling (RT) and direct drilling with no tillage (NT), and II) bare soil (BS) without crop cover tilled by ploughing plus two levelling. In more than 90% of the study cases, soil losses were collected for single rain events with erosive power, whose erosivity was calculated. Total rain recorded during the 20 year experimental period was approximately 66,400 mm, which is equivalent to roughly 105,700, MJ mm ha-1 h-1 (EI30), whereas soil losses in the BS treatment were higher than 1,700 t.ha-1. On average, soil losses under RT treatment showed a 92% reduction in relation with BS, whereas under CT the reduction in relation to BS was about 66%. Soil management by direct drilling (NT) was the most efficient system to minimize water erosion, as soil losses decreased about 98% when compared with BS. Moreover, soil management systems with a crop

  14. Coreceptor Usage, Diversity, and Divergence in Drug-Naive and Drug-Exposed Individuals from Malawi, Infected with HIV-1 Subtype C for More Than 20 Years

    PubMed Central

    Seager, Ishla; Travers, Simon A.; Leeson, Michael D.; Crampin, Amelia C.; French, Neil; Glynn, Judith R.

    2014-01-01

    Abstract There are few cohorts of individuals who have survived infection with HIV-1 for more than 20 years, reported and followed in the literature, and even fewer from Africa. Here we present data on a cohort of subtype C-infected individuals from rural northern Malawi. By sequencing multiple clones from long-term survivors at different time points, and using multiple genotyping approaches, we show that 5 of the 11 individuals are predicted as CXCR4 using (by ≥3/5 predictors) but only one individual is predicted as CXCR4 using by all five algorithms. Using any one genotyping approach overestimates the number of predicted CXCR4 sequences. Patterns of diversity and divergence were variable between the HIV-1 long-term survivors with some individuals showing very small amounts of variation and change, and others showing a greater amount; both patterns are consistent with what has been described in the literature. PMID:24925099

  15. Reconceptualizing Knowledge at the Mathematical Horizon

    ERIC Educational Resources Information Center

    Zazkis, Rina; Mamolo, Ami

    2011-01-01

    This article extends the notion of "knowledge at the mathematical horizon" or "horizon knowledge" introduced by Ball and colleagues as a part of teachers' subject matter knowledge. Our focus is on teachers' mathematical knowledge beyond the school curriculum, that is, on mathematics learnt during undergraduate college or university studies. We…

  16. The NMC Horizon Report: 2015 Museum Edition

    ERIC Educational Resources Information Center

    Johnson, L.; Adams Becker, S.; Estrada, V.; Freeman, A.

    2015-01-01

    The internationally recognized series of "Horizon Reports" is part of the New Media Consortium's Horizon Project, a comprehensive research venture established in 2002 that identifies and describes emerging technologies likely to have a large impact over the coming years on a variety of sectors around the globe. This "2015 Horizon…

  17. Expanding your horizons in science and mathematics

    NASA Technical Reports Server (NTRS)

    Palmer, Cynthia E. A.

    1995-01-01

    The purpose of the 'Expanding Your Horizons in Science and Mathematics' program is to interest young women in grades six through twelve in a variety of careers where mathematics and science are important. Progress in encouraging young women to take courses in mathematics, science, and technological subjects is discussed. Also included are adult, student, and organizational information packets used for 'Expanding Your Horizons' conferences.

  18. The NMC Horizon Report: 2014 Library Edition

    ERIC Educational Resources Information Center

    Johnson, L.; Adams Becker, S.; Estrada, V.; Freeman, A.

    2014-01-01

    The internationally recognized "NMC Horizon Report" series and regional "NMC Technology Outlooks" are part of the NMC Horizon Project, a 12-year effort established in 2002 that annually identifies and describes emerging technologies likely to have a large impact over the coming five years in every sector of education around the…

  19. The Horizon Report: 2010 Museum Edition

    ERIC Educational Resources Information Center

    Johnson, L.; Witchey, H.; Smith, R.; Levine, A.; Haywood, K.

    2010-01-01

    The internationally recognized series of "Horizon Reports" is part of the New Media Consortium's Horizon Project, a comprehensive research venture established in 2002 that identifies and describes emerging technologies likely to have a large impact over the coming five years on a variety of sectors around the globe. This volume, the "2010 Horizon…

  20. Nitrogen isotopes of coral skeleton-bound organic matter and a 20-year record from Central Equatorial Pacific

    NASA Astrophysics Data System (ADS)

    Wang, X.; Sigman, D. M.; Sinclair, D.; Sherrell, R. M.; Rafter, P. A.; Ren, H.; Cobb, K.; Weigand, A.; Oleynik, S.

    2011-12-01

    We have developed a sensitive method for measuring nitrogen isotopes of coral skeleton-bound organic matter, requiring 5 mg of chemically cleaned coral skeleton powder and yielding a standard deviation for measured d15N of ~0.3%. This method allows for the generation of high-resolution d15N records of coral skeleton-bound organic matter, which we seek to advance as a proxy for the ocean nitrogen cycle in the past. A 20-year coral d15N record (1977-1997) from the Central Equatorial Pacific (Line Islands, Kiribati (2°N, 157°W)) yields an average d15N of 13%, which is similar to the d15N of mixed layer nitrate in this region but 6% higher than the subsurface nitrate being upwelled in this region. The 21 samples over this 20 year period yield a range of only 1.5% (12.5-14.0%), suggesting no substantial change of the mixed layer nitrogen pool over this period. There is some evidence for a lower d15N during El Nino events, but this requires testing by extension of the record and higher resolution sampling. If robust, this d15N decrease may reflect an increased reliance of corals on particulate organic nitrogen and recycled forms of nitrogen relative to nitrate during El Nino events, when mixed layer nitrate concentration declines in the Central Equatorial Pacific.

  1. Agoraphobia With and Without Panic Disorder: A 20-Year Follow-up of Integrated Exposure and Psychodynamic Therapy.

    PubMed

    Hoffart, Asle; Hedley, Liv M; Svanøe, Karol; Langkaas, Tomas Formo; Sexton, Harold

    2016-02-01

    The aim of the current study was to compare the 20-year outcome in panic disorder with agoraphobia (PD with AG) and agoraphobia without panic disorder (AG without PD) patients after inpatient psychological treatment. Of 53 eligible patients having completed a medication-free integrated exposure and psychodynamic treatment, 38 (71.7%)-25 PD with AG and 13 AG without PD patients-attended 20-year follow-up. AG without PD patients improved less than PD with AG patients did on primary outcome measures. In the PD with AG group, there were large uncontrolled effect sizes (<-2.30). More of the AG without PD patients had avoidant personality disorder at pretreatment, but the presence of this disorder did not predict outcome. The follow-up results support that PD with AG and AG without PD are two different disorders. The results also suggest that the very long-term outcome in PD with AG patients is excellent for this integrated treatment. PMID:26588081

  2. Agoraphobia With and Without Panic Disorder: A 20-Year Follow-up of Integrated Exposure and Psychodynamic Therapy.

    PubMed

    Hoffart, Asle; Hedley, Liv M; Svanøe, Karol; Langkaas, Tomas Formo; Sexton, Harold

    2016-02-01

    The aim of the current study was to compare the 20-year outcome in panic disorder with agoraphobia (PD with AG) and agoraphobia without panic disorder (AG without PD) patients after inpatient psychological treatment. Of 53 eligible patients having completed a medication-free integrated exposure and psychodynamic treatment, 38 (71.7%)-25 PD with AG and 13 AG without PD patients-attended 20-year follow-up. AG without PD patients improved less than PD with AG patients did on primary outcome measures. In the PD with AG group, there were large uncontrolled effect sizes (<-2.30). More of the AG without PD patients had avoidant personality disorder at pretreatment, but the presence of this disorder did not predict outcome. The follow-up results support that PD with AG and AG without PD are two different disorders. The results also suggest that the very long-term outcome in PD with AG patients is excellent for this integrated treatment.

  3. Estimation of the Horizon in Photographed Outdoor Scenes by Human and Machine

    PubMed Central

    Herdtweck, Christian; Wallraven, Christian

    2013-01-01

    We present three experiments on horizon estimation. In Experiment 1 we verify the human ability to estimate the horizon in static images from only visual input. Estimates are given without time constraints with emphasis on precision. The resulting estimates are used as baseline to evaluate horizon estimates from early visual processes. Stimuli are presented for only ms and then masked to purge visual short-term memory and enforcing estimates to rely on early processes, only. The high agreement between estimates and the lack of a training effect shows that enough information about viewpoint is extracted in the first few hundred milliseconds to make accurate horizon estimation possible. In Experiment 3 we investigate several strategies to estimate the horizon in the computer and compare human with machine “behavior” for different image manipulations and image scene types. PMID:24349073

  4. Digital depth horizon compilations of the Alaskan North Slope and adjacent Arctic regions

    USGS Publications Warehouse

    Saltus, Richard W.; Bird, Kenneth J.

    2003-01-01

    Data have been digitized and combined to create four detailed depth horizon grids spanning the Alaskan North Slope and adjacent offshore areas. These map horizon compilations were created to aid in petroleum system modeling and related studies. Topography/bathymetry is extracted from a recent Arctic compilation of global onshore DEM and satellite altimetry and ship soundings offshore. The Lower Cretaceous Unconformity (LCU), the top of the Triassic Shublik Formation, and the pre-Carboniferous acoustic basement horizon grids are created from numerous seismic studies, drill hole information, and interpolation. These horizons were selected because they mark critical times in the geologic evolution of the region as it relates to petroleum. The various horizons clearly show the major tectonic elements of this region including the Brooks Range, Colville Trough, Barrow Arch, Hanna Trough, Chukchi Platform, Nuwuk Basin, Kaktovik Basin, and Canada Basin. The gridded data are available in a variety of data formats for use in regional studies.

  5. Something special at the event horizon

    NASA Astrophysics Data System (ADS)

    Eune, Myungseok; Gim, Yongwan; Kim, Wontae

    2014-12-01

    We revisit the free-fall energy density of scalar fields semiclassically by employing the trace anomaly on a two-dimensional Schwarzschild black hole with respect to various black hole states in order to clarify whether something special at the horizon happens or not. For the Boulware state, the energy density at the horizon is always negative divergent, which is independent of initial free-fall positions. However, in the Unruh state the initial free-fall position is responsible for the energy density at the horizon and there is a critical point to determine the sign of the energy density at the horizon. In particular, a huge negative energy density appears when the freely falling observer is dropped just near the horizon. For the Hartle-Hawking state, it may also be positive or negative depending on the initial free-fall position, but it is always finite. Finally, we discuss physical consequences of these calculations.

  6. Gravitational black hole hair from event horizon supertranslations

    NASA Astrophysics Data System (ADS)

    Averin, Artem; Dvali, Gia; Gomez, Cesar; Lüst, Dieter

    2016-06-01

    We discuss BMS supertranslations both at null-infinity BMS- and on the horizon {BMS}^{mathscr{H}} for the case of the Schwarzschild black hole. We show that both kinds of supertranslations lead to infinetly many gapless physical excitations. On this basis we construct a quotient algebra mathcal{A}equiv {BMS}^{mathscr{H}}/{BMS}- using suited superpositions of both kinds of transformations which cannot be compensated by an ordinary BMS-supertranslation and therefore are intrinsically due to the presence of an event horizon. We show that transformations in mathcal{A} are physical and generate gapless excitations on the horizon that can account for the gravitational hair as well as for the black hole entropy. We identify the physics of these modes as associated with Bogolioubov-Goldstone modes due to quantum criticality. Classically the number of these gapless modes is infinite. However, we show that due to quantum criticality the actual amount of information-carriers becomes finite and consistent with Bekenstein entropy. Although we only consider the case of Schwarzschild geometry, the arguments are extendable to arbitrary space-times containing event horizons.

  7. 20 Years of EUROCALL: Learning from the Past, Looking to the Future. Proceedings [of the] 2013 EUROCALL Conference (Évora, Portugal, September 11-14, 2013)

    ERIC Educational Resources Information Center

    Bradley, Linda, Ed.; Thouësny, Sylvie, Ed.

    2013-01-01

    EUROCALL 2013's theme was "20 Years of EUROCALL: Learning from the Past, Looking to the Future." The conference seeked to establish an overview of EUROCALL's twentieth anniversary. As a professional organization, EUROCALL has been aiming, along its 20 years of existence, to promote innovative research, development and practice in the…

  8. Cytochrome P4501A biomarker indication of oil exposure in harlequin ducks up to 20 years after the Exxon Valdez oil spill

    USGS Publications Warehouse

    Esler, Daniel; Trust, Kimberly A.; Ballachey, Brenda E.; Iverson, Samuel A.; Lewis, Tyler L.; Rizzolo, Daniel; Mulcahy, Daniel M.; Miles, A. Keith; Woodin, Bruce R.; Stegeman, John J.; Henderson, John D.; Wilson, Barry W.

    2010-01-01

    Hydrocarbon-inducible cytochrome P4501A (CYP1A) expression was measured, as ethoxyresorufin-O-deethylase (EROD) activity, in livers of wintering harlequin ducks (Histrionicus histrionicus) captured in areas of Prince William Sound, Alaska, USA, oiled by the 1989 Exxon Valdez spill and in birds from nearby unoiled areas, during 2005 to 2009 (up to 20 years following the spill). The present work repeated studies conducted in 1998 that demonstrated that in harlequin ducks using areas that received Exxon Valdez oil, EROD activity was elevated nearly a decade after the spill. The present findings strongly supported the conclusion that average levels of hepatic EROD activity were higher in ducks from oiled areas than those from unoiled areas during 2005 to 2009. This result was consistent across four sampling periods; furthermore, results generated from two independent laboratories using paired liver samples from one of the sampling periods were similar. The EROD activity did not vary in relation to age, sex, or body mass of individuals, nor did it vary strongly by season in birds collected early and late in the winter of 2006 to 2007, indicating that these factors did not confound inferences about observed differences between oiled and unoiled areas. We interpret these results to indicate that harlequin ducks continued to be exposed to residual Exxon Valdez oil up to 20 years after the original spill. This adds to a growing body of literature suggesting that oil spills have the potential to affect wildlife for much longer time frames than previously assumed.

  9. A retrospective analysis of 20-year data of the surgical management of ulcerative colitis patients in Taiwan: a study of Taiwan Society of Inflammatory Bowel Disease

    PubMed Central

    Lin, Chun-Chi; Wei, Shu-Chen; Lin, Been-Ren; Tsai, Wen-Sy; Chen, Jinn-Shiun; Hsu, Tzu-Chi; Lin, Wei-Chen; Huang, Tien-Yu; Chao, Te-Hsin; Lin, Hung-Hsin; Wong, Jau-Min

    2016-01-01

    Background/Aims With the recent progress in medical treatment, surgery still plays a necessary and important role in treating ulcerative colitis (UC) patients. In this study, we analyzed the surgical results and outcomes of UC in Taiwan in the recent 20 years, via a multi-center study through the collaboration of Taiwan Society of IBD. Methods A retrospective analysis of surgery data of UC patients from January 1, 1995, through December 31, 2014, in 6 Taiwan major medical centers was conducted. The patients' demographic data, indications for surgery, and outcome details were recorded and analyzed. Results The data of 87 UC patients who received surgical treatment were recorded. The median post-operative follow-up duration was 51.1 months and ranged from 0.4 to 300 months. The mean age at UC diagnosis was 45.3±16.0 years and that at operation was 48.5±15.2 years. The 3 leading indications for surgical intervention were uncontrolled bleeding (16.1%), perforation (13.8%), and intractability (12.6%). In total, 27.6% of surgeries were performed in an emergency setting. Total or subtotal colectomy with rectal preservation (41.4%) was the most common operation. There were 6 mortalities, all due to sepsis. Emergency operation and low pre-operative albumin level were significantly associated with poor survival (P=0.013 and 0.034, respectively). Conclusions In the past 20 years, there was no significant change in the indications for surgery in UC patients. Emergency surgeries and low pre-operative albumin level were associated with poor survival. Therefore, an optimal timing of elective surgery for people with poorly controlled UC is paramount. PMID:27433147

  10. Surgical Treatment of Primary Intracardiac Myxoma: 20-Year Experience in “Shahid Modarres Hospital”—A Tertiary University Hospital—Tehran, Iran

    PubMed Central

    Ansari Aval, Zahra; Ghaderi, Hamid; Tatari, Hassan; Foroughi, Mahnoosh; Mirjafari, Seyedeh Adeleh; Forozeshfard, Mohammad; Fani, Kamal; Khaheshi, Isa

    2015-01-01

    Although cardiac tumors are not common they may vary in terms of race and surgical approach in different countries. Method. Patients data of 20 years was collected and evaluated in the “Shahid Modarres Hospital”—a tertiary university hospital—Tehran, Iran. Results. 42 patients with cardiac myxoma (all cases in 20 years) were included in study, 17 males and 25 females, age difference: 13 to 76 years (mean 50.6). Most of patients were in functional classes I, II. 35 patients complained of dyspnea and 3 patients had embolic events. 97.6% of tumors were primary (41 patients) and one tumor was recurrent (2.4%), 85.7% of tumors (36 cases) were located in LA, and 88.1% of tumors (37 cases) were pediculated. 40 patients (95%) had one tumor. In 22 patients (52.3%) after tumor resection septal defects were repaired primarily while in 18 patients (42.8%) the defects were repaired with pericardial patch and In one patient, tumor resected without any septal defect. Mean tumor size was about 5.22 cm (range of 2.2 to 8.2 cm). Postoperatively, 33 patients discharged from hospital without any complication. Discussion. The research reveals that patients' age and gender were similar to that of other studies in other countries while tumor's incidence seems to be higher. 3 patients were diagnosed after remote embolic event and one patient was diagnosed after MI reflecting relatively high tumor complications and late diagnosis. Conclusion. In our study mean time from diagnosis to operation was too long. The patients had more preoperative embolic events and complication. However, size of myxoma and location of that was as same as its rate in the other literature. As recommendation we suggested that in all patients with vague chest pain or remote embolic events cardiac myxomas should be ruled out. PMID:25688375

  11. New Horizons' Extreme Close-Up of Pluto’s Surface (no audio)

    NASA Video Gallery

    This is the most detailed view of Pluto’s terrain you’ll see for a very long time. This mosaic strip – extending across the hemisphere that faced the New Horizons spacecraft as it flew past Pluto o...

  12. Microbiological monitoring of bivalves from the Ria Formosa Lagoon (south coast of Portugal): a 20 years of sanitary survey.

    PubMed

    Almeida, Catarina; Soares, Florbela

    2012-02-01

    The microbiological pollution of coastal waters is a major problem, especially in shellfish areas. This article shows the faecal contamination in bivalves from the Ria Formosa Lagoon (south coast of Portugal) along 20 years (1990-2009). The highest values of Escherichia coli in bivalves were obtained during the 90s, related with the discharge of untreated wastewaters and agricultural runoff. In the 2000s contamination levels decreased, with 83% of the population already served by new or remodelled sewage treatment plants. The highest levels were found in bivalves close to the largest city, where punctual and diffuse contamination sources still exist. Bivalves from the less impacted site showed the lowest contamination, an area with more water renewal. Seasonally, the highest levels were in autumn and winter, due to the runoff of waters from rainfall. These were opposite to those in spring and summer, when the highest temperatures and salinity showed a bactericidal effect. PMID:22197556

  13. Microbiological monitoring of bivalves from the Ria Formosa Lagoon (south coast of Portugal): a 20 years of sanitary survey.

    PubMed

    Almeida, Catarina; Soares, Florbela

    2012-02-01

    The microbiological pollution of coastal waters is a major problem, especially in shellfish areas. This article shows the faecal contamination in bivalves from the Ria Formosa Lagoon (south coast of Portugal) along 20 years (1990-2009). The highest values of Escherichia coli in bivalves were obtained during the 90s, related with the discharge of untreated wastewaters and agricultural runoff. In the 2000s contamination levels decreased, with 83% of the population already served by new or remodelled sewage treatment plants. The highest levels were found in bivalves close to the largest city, where punctual and diffuse contamination sources still exist. Bivalves from the less impacted site showed the lowest contamination, an area with more water renewal. Seasonally, the highest levels were in autumn and winter, due to the runoff of waters from rainfall. These were opposite to those in spring and summer, when the highest temperatures and salinity showed a bactericidal effect.

  14. Reclaiming the individual from Hofstede's ecological analysis--a 20-year odyssey: comment on Oyserman et al. (2002).

    PubMed

    Bond, Michael Harris

    2002-01-01

    D. Oyserman, H. M. Coon, and M. Kemmelmeier (2002) challenge the stereotype that European Americans are more individualistic and less collectivistic than persons from most other ethnic groups. The author contends that this stereotype took firm empirical root with G. Hofstede's (1980) monumental publication identifying the United States as the most individualistic of his then 40 nations. This empirical designation arose because of challengeable decisions Hofstede made about the analysis of his data and the labeling of his dimensions. The conflation of concepts under the rubric of cultural individualism plus psychologists' unwarranted psychologizing of the construct then combined with Hofstede's empirical location of America to set a 20-year agenda for data collection. Oyserman et al. disentangle and organize this mass of studies, enabling the discipline of cross-cultural psychology to forge ahead in more productive directions, less reliant on previous assumptions and measures.

  15. Reclaiming the individual from Hofstede's ecological analysis--a 20-year odyssey: comment on Oyserman et al. (2002).

    PubMed

    Bond, Michael Harris

    2002-01-01

    D. Oyserman, H. M. Coon, and M. Kemmelmeier (2002) challenge the stereotype that European Americans are more individualistic and less collectivistic than persons from most other ethnic groups. The author contends that this stereotype took firm empirical root with G. Hofstede's (1980) monumental publication identifying the United States as the most individualistic of his then 40 nations. This empirical designation arose because of challengeable decisions Hofstede made about the analysis of his data and the labeling of his dimensions. The conflation of concepts under the rubric of cultural individualism plus psychologists' unwarranted psychologizing of the construct then combined with Hofstede's empirical location of America to set a 20-year agenda for data collection. Oyserman et al. disentangle and organize this mass of studies, enabling the discipline of cross-cultural psychology to forge ahead in more productive directions, less reliant on previous assumptions and measures. PMID:11843548

  16. Recurrence of cervical myelopathy secondary to a strut graft fracture 20 years after anterior decompression and fusion: a case report.

    PubMed

    Kida, Kazunobu; Takaya, Shogo; Tadokoro, Nobuaki; Kumon, Masashi; Kiyasu, Katsuhito; Kato, Tomonari; Takemasa, Ryuichi; Ikeuchi, Masahiko; Tani, Toshikazu

    2015-08-01

    This study reports on a 70-year-old man with recurrent cervical myelopathy 20 years after anterior decompression and fusion of C4-7 using a free vascularised strut graft. The recurrent myelopathy was secondary to a kyphotic deformity of a fractured graft and residual ossification of the posterior longitudinal ligament with stenosis at C3/4. Intraoperative spinal cord-evoked potentials indicated that spinal cord traction secondary to progressive kyphosis of the cervical spine after the graft fracture was the cause. The patient underwent laminoplasty at C3 and laminectomy at C4 to decompress the stenosis at C3/4 as well as posterior cervical spinal fusion at C3-7 with pedicle screws and a lateral mass screw and a bone graft to prevent further progression of the kyphosis. At postoperative 18 months, the patient's Japanese Orthopaedic Association score had improved to 14 from 8, and he could walk without support. PMID:26321562

  17. Quasilocal approach to general universal horizons

    NASA Astrophysics Data System (ADS)

    Maciel, Alan

    2016-05-01

    Theories of gravity with a preferred foliation usually display arbitrarily fast signal propagation, changing the black hole definition. A new inescapable barrier, the universal horizon, has been defined and many static and spherically symmetric examples have been studied in the literature. Here, we translate the usual definition of the universal horizon in terms of an optical scalar built with the preferred flow defined by the preferred spacetime foliation. The new expression has the advantages of being of quasilocal nature and independent of specific spacetime symmetries in order to be well defined. Therefore, we propose it as a definition for general quasilocal universal horizons. Using the new formalism, we show that there is no universal analog of cosmological horizons for Friedmann-Lemaître-Robertson-Walker models for any scale factor function, and we also state that quasilocal universal horizons are restricted to trapped regions of the spacetime. Using the evolution equation, we analyze the formation of universal horizons under a truncated Hořava-Lifshitz theory, in spherical symmetry, showing the existence of regions in parameter space where the universal horizon formation cannot be smooth from the center, under some physically reasonable assumptions. We conclude with our view on the next steps for the understanding of black holes in nonrelativistic gravity theories.

  18. Climate-change-related shifts in annual phenology of a temperate snake during the last 20 years

    NASA Astrophysics Data System (ADS)

    Rugiero, Lorenzo; Milana, Giuliano; Petrozzi, Fabio; Capula, Massimo; Luiselli, Luca

    2013-08-01

    Global warming is thought to be a far-reaching threat to biodiversity, and is supposed to influence several aspects of the ecology of animals. Global warming should influence especially the ectotherm vertebrates, which depend directly from the external thermal conditions for their activities and performances. Here, we analyze the changes in phenology which have occurred in the last 20 years in a marked population of vipers, Vipera aspis, and we try to relate these changes with the intervening climatic changes. We analyzed three metrics of viper's annual phenology: (i) annual onset of above-ground activity (hereby AOA); (ii) annual onset of feeding period (AOF); (iii) annual onset of the hibernation (AOH). The annual variations of these three phenological metrics were correlated to five variables of climatic data: (1) mean annual air temperature, (2) mean February air temperature, (3) mean July air temperature, (4) yearly number of rainy days, and (5) yearly number of days with rainstorm. We observed a statistically significant reduction of AOA values from >28 days between 1987 and 1997, to approximately 20 days from 1998 to 2011, with a similar statistical trend also found for AOF values. The number of days of delay in entering hibernation increased significantly since 1998. Three sets of relationships between climatic variables and metrics of viper phenology were statistically significant, i.e. the correlation (i) between annual mean temperature and AOA (negative), (ii) between annual mean temperature and AOF (negative), and (iii) between annual mean temperature and AOH (positive). The percent of field days (between 20th February and 20th March) with no viper observed also decreased significantly over the years. Our study showed that three different traits of the annual phenology of a Mediterranean snake are shifting in the 20+ years of monitoring, and that there is correlational evidence that these shifts are linked to intervening climate change.

  19. Developmental histories of perceived racial discrimination and diurnal cortisol profiles in adulthood: A 20-year prospective study.

    PubMed

    Adam, Emma K; Heissel, Jennifer A; Zeiders, Katharine H; Richeson, Jennifer A; Ross, Emily C; Ehrlich, Katherine B; Levy, Dorainne J; Kemeny, Margaret; Brodish, Amanda B; Malanchuk, Oksana; Peck, Stephen C; Fuller-Rowell, Thomas E; Eccles, Jacquelynne S

    2015-12-01

    Perceived racial discrimination (PRD) has been associated with altered diurnal cortisol rhythms in past cross-sectional research. We investigate whether developmental histories of PRD, assessed prospectively, are associated with adult diurnal cortisol profiles. One-hundred and twelve (N=50 Black, N=62 White) adults from the Maryland Adolescent Development in Context Study provided saliva samples in adulthood (at approximately age 32 years) at waking, 30min after waking, and at bedtime for 7 days. Diurnal cortisol measures were calculated, including waking cortisol levels, diurnal cortisol slopes, the cortisol awakening response (CAR), and average daily cortisol (AUC). These cortisol outcomes were predicted from measures of PRD obtained over a 20-year period beginning when individuals were in 7th grade (approximately age 12). Greater average PRD measured across the 20-year period predicted flatter adult diurnal cortisol slopes for both Black and White adults, and a lower CAR. Greater average PRD also predicted lower waking cortisol for Black, but not White adults. PRD experiences in adolescence accounted for many of these effects. When adolescent and young adult PRD are entered together predicting cortisol outcomes, PRD experiences in adolescence (but not young adulthood) significantly predicted flatter diurnal cortisol slopes for both Black and White adults. Adolescent, but not young adult PRD, also significantly predicted lower waking and lower average cortisol for Black adults. Young adult PRD was, however, a stronger predictor of the CAR, predicting a marginally lower CAR for Whites, and a significantly larger CAR for Blacks. Effects were robust to controlling for covariates including health behaviors, depression, income and parent education levels. PRD experiences interacted with parent education and income to predict aspects of the diurnal cortisol rhythm. Although these results suggest PRD influences on cortisol for both Blacks and Whites, the key findings

  20. Estimating the Burden of Leptospirosis among Febrile Subjects Aged below 20 Years in Kampong Cham Communities, Cambodia, 2007-2009

    PubMed Central

    Hem, Sopheak; Ly, Sowath; Votsi, Irene; Vogt, Florian; Asgari, Nima; Buchy, Philippe; Heng, Seiha; Picardeau, Mathieu; Sok, Touch; Ly, Sovann; Huy, Rekol; Guillard, Bertrand; Cauchemez, Simon; Tarantola, Arnaud

    2016-01-01

    Background Leptospirosis is an emerging but neglected public health challenge in the Asia/Pacific Region with an annual incidence estimated at 10–100 per 100,000 population. No accurate data, however, are available for at-risk rural Cambodian communities. Method We conducted anonymous, unlinked testing for IgM antibodies to Leptospira spp. on paired sera of Cambodian patients <20 years of age between 2007–2009 collected through active, community-based surveillance for febrile illnesses in a convenience sample of 27 rural and semi-rural villages in four districts of Kampong Cham province, Cambodia. Leptospirosis testing was done on paired serological samples negative for Dengue, Japanese encephalitis and Chikungunya viruses after random selection. Convalescent samples found positive while initial samples were negative were considered as proof of acute infection. We then applied a mathematical model to estimate the risk of fever caused by leptospirosis, dengue or other causes in rural Cambodia. Results A total of 630 samples are coming from a randomly selected subset of 2358 samples. IgM positive were found on the convalescent serum sample, among which 100 (15.8%) samples were IgM negative on an earlier sample. Seventeen of these 100 seroconversions were confirmed using a Microagglutination Test. We estimated the probability of having a fever due to leptospirosis at 1. 03% (95% Credible Interval CI: 0. 95%–1. 22%) per semester. In comparison, this probability was 2. 61% (95% CI: 2. 55%, 2. 83%) for dengue and 17. 65% (95% CI: 17. 49%, 18. 08%) for other causes. Conclusion Our data from febrile cases aged below 20 years suggest that the burden of leptospirosis is high in rural Cambodian communities. This is especially true during the rainy season, even in the absence of identified epidemics. PMID:27043016