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Sample records for extremely important discovery-the

  1. The importance of range edges for an irruptive species during extreme weather events

    USGS Publications Warehouse

    Bateman, Brooke L.; Pidgeon, Anna M.; Radeloff, Volker C.; Allstadt, Andrew J.; Akçakaya, H. Resit; Thogmartin, Wayne E.; Vavrus, Stephen J.; Heglund, Patricia J.

    2015-01-01

    In a changing climate where more frequent extreme weather may be more common, conservation strategies for weather-sensitive species may require consideration of habitat in the edges of species’ ranges, even though non-core areas may be unoccupied in ‘normal’ years. Our results highlight the conservation importance of range edges in providing refuge from extreme events, such as drought, and climate change.

  2. An important Norwegian contribution to the study of the bursae of the upper and lower extremities

    PubMed Central

    2010-01-01

    We present a critical analysis of the monograph of A.S.D. Synnestvedt (1869) “En anatomisk beskrivelse af de paa over- og underestremiteterne forekommende Bursae mucosae”. The analysis was completed using anatomical information from the historically oldest publications dealing with the bursae of the extremities: Albinus (1734), Monro (1788), Rosenmüller (1799). We are of the opinion that Synnestvedt's publication is important, not only historically but also as a source of information for recent medical practitioners. Synnestvedt's monograph has a wealth of literary citations, unambiguous opinions of seasoned anatomists regarding the structure and function of the synovial membrane, and detailed descriptions of dissections he performed on fetal and adult cadavers. The information in this publication may enhance the diagnosis of bursopathies and enthesopathies of the extremities. PMID:20860444

  3. Daily temperature extremes play an important role in predicting thermal effects.

    PubMed

    Ma, Gang; Hoffmann, Ary A; Ma, Chun-Sen

    2015-07-01

    Organisms in natural environments experience diel temperature fluctuations, including sporadic extreme conditions, rather than constant temperatures. Studies based mainly on model organisms have tended to focus on responses to average temperatures or short-term heat stress, which overlooks the potential impact of daily fluctuations, including stressful daytime periods and milder night-time periods. Here, we focus on daily maximum temperatures, while holding night-time temperatures constant, to specifically investigate the effects of high temperature on demographic parameters and fitness in the English grain aphid Sitobion avenae. We then compared the observed effects of different daily maximum temperatures with predictions from constant temperature-performance expectations. Moderate daily maximum temperatures depressed aphid performance while extreme conditions had dramatic effects, even when mean temperatures were below the critical maximum. Predictions based on daily average temperature underestimated negative effects of temperature on performance by ignoring daily maximum temperature, while predictions based on daytime maximum temperatures overestimated detrimental impacts by ignoring recovery under mild night-time temperatures. Our findings suggest that daily maximum temperature will play an important role in regulating natural population dynamics and should be considered in predictions. These findings have implications for natural population dynamics, particularly when considering the expected increase in extreme temperature events under climate change. PMID:26026043

  4. The importance of the eastward zonal current for generating extreme El Niño

    NASA Astrophysics Data System (ADS)

    Kim, WonMoo; Cai, Wenju

    2014-06-01

    Extreme El Niño (e.g., 1983/1983 and 1997/1998) causes severe weather and climate impacts globally, but the associated dynamics is not fully understood. The present study shows that advection of mean temperature by anomalous eastward zonal current plays an important role in producing such extreme events especially during the early part of the developing period. While the climatological direction of the upper oceanic current in the equatorial Pacific is westward, at times the direction reverses. These eastward current events are well distinguished from the normal, westward conditions. The upper-layer zonal current in the equatorial Pacific is basically in geostrophic balance and forced by wind stress. However, in the case of the eastward zonal current events, persistent westerly winds are observed in the Western Pacific, and the current becomes synchronized with the westerly wind stress above. The advection of the mean temperature by the anomalous zonal current in the early developing period always precedes strong El Niño, though it does not significantly contribute to the growth of La Niña, neutral, and moderate El Niño; and is the major contributor of asymmetry in the early developing phase.

  5. Communicating natural hazards. The case of marine extreme events and the importance of the forecast's errors.

    NASA Astrophysics Data System (ADS)

    Marone, Eduardo; Camargo, Ricardo

    2013-04-01

    possible to produce short and long term forecasts. While the statistic of extremes is useful for many stakeholders, short term forecasts could be of importance for the whole society. Whatever the case, the prediction errors have to be emphasizes even more than the forecasts. The most common forecast in terms of general public understanding is the weather prediction. Nowadays, general public knows it well enough to properly deal with the uncertainties, because after so many year of not perfect forecasts, society knows the limits. Other coastal hazards deserve to be presented more carefully, and some successful example of the use of the precautionary principle could be observed, for instance, on the Pacific Tsunami alert system. Nowadays, the preparedness of the coastal population is good enough (even in such big and diverse area) not to be bored to run up the hill, most of the times unnecessarily, because they know the uncertainty and accept it. The key issue we, scientists, have to work better at any level, is the need of properly estimate and communicate the uncertainties of our results, cause they are not obvious nor irrelevant.

  6. Understanding the importance of natural neuromotor strategy in upper extremity neuroprosthetic control.

    PubMed

    Nathan, Dominic E; Prost, Robert W; Guastello, Stephen J; Jeutter, Dean C

    2014-01-01

    A key challenge in upper extremity neuroprosthetics is variable levels of skill and inconsistent functional recovery. We examine the feasibility and benefits of using natural neuromotor strategies through the design and development of a proof-of-concept model for a feed-forward upper extremity neuroprosthetic controller. Developed using Artificial Neural Networks, the model is able to extract and classify neural correlates of movement intention from multiple brain regions that correspond to functional movements. This is unique compared to contemporary controllers that record from limited physiological sources or require learning of new strategies. Functional MRI (fMRI) data from healthy subjects (N = 13) were used to develop the model, and a separate group (N = 4) of subjects were used for validation. Results indicate that the model is able to accurately (81%) predict hand movement strictly from the neural correlates of movement intention. Information from this study is applicable to the development of upper extremity technology aided interventions. PMID:24589839

  7. The importance of interacting climate modes on Australia’s contribution to global carbon cycle extremes

    PubMed Central

    Cleverly, James; Eamus, Derek; Luo, Qunying; Restrepo Coupe, Natalia; Kljun, Natascha; Ma, Xuanlong; Ewenz, Cacilia; Li, Longhui; Yu, Qiang; Huete, Alfredo

    2016-01-01

    The global carbon cycle is highly sensitive to climate-driven fluctuations of precipitation, especially in the Southern Hemisphere. This was clearly manifested by a 20% increase of the global terrestrial C sink in 2011 during the strongest sustained La Niña since 1917. However, inconsistencies exist between El Niño/La Niña (ENSO) cycles and precipitation in the historical record; for example, significant ENSO–precipitation correlations were present in only 31% of the last 100 years, and often absent in wet years. To resolve these inconsistencies, we used an advanced temporal scaling method for identifying interactions amongst three key climate modes (El Niño, the Indian Ocean dipole, and the southern annular mode). When these climate modes synchronised (1999–2012), drought and extreme precipitation were observed across Australia. The interaction amongst these climate modes, more than the effect of any single mode, was associated with large fluctuations in precipitation and productivity. The long-term exposure of vegetation to this arid environment has favoured a resilient flora capable of large fluctuations in photosynthetic productivity and explains why Australia was a major contributor not only to the 2011 global C sink anomaly but also to global reductions in photosynthetic C uptake during the previous decade of drought. PMID:26976754

  8. On the Importance of the Flare's Late Phase for the Solar Extreme Ultraviolet Irradiance

    NASA Technical Reports Server (NTRS)

    Woods, Thomas N.; Eparvier, Frank; Jones, Andrew R.; Hock, Rachel; Chamberlin, Phillip C.; Klimchuk, James A.; Didkovsky, Leonid; Judge, Darrell; Mariska, John; Bailey, Scott; Tobiska, W. Kent; Schrijver, Carolus J.; Webb, David F.; Warren, Harry

    2011-01-01

    The new solar extreme ultraviolet (EUV) irradiance observations from NASA Solar Dynamics Observatory (SDO) have revealed a new class of solar flares that are referred to as late phase flares. These flares are characterized by the hot 2-5 MK coronal emissions (e.g., Fe XVI 33.5 nm) showing large secondary peaks that appear many minutes to hours after an eruptive flare event. In contrast, the cool 0.7-1.5 MK coronal emissions (e.g., Fe IX 17.1 nm) usually dim immediately after the flare onset and do not recover until after the delayed second peak of the hot coronal emissions. We refer to this period of 1-5 hours after the fl amrea sin phase as the late phase, and this late phase is uniquely different than long duration flares associated with 2-ribbon flares or large filament eruptions. Our analysis of the late phase flare events indicates that the late phase involves hot coronal loops near the flaring region, not directly related to the original flaring loop system but rather with the higher post-eruption fields. Another finding is that space weather applications concerning Earth s ionosphere and thermosphere need to consider these late phase flares because they can enhance the total EUV irradiance flare variation by a factor of 2 when the late phase contribution is included.

  9. An archaeal iron-oxidizing extreme acidophile important in acid mine drainage.

    PubMed

    Edwards, K J; Bond, P L; Gihring, T M; Banfield, J F

    2000-03-10

    A new species of Archaea grows at pH approximately 0.5 and approximately 40 degrees C in slime streamers and attached to pyrite surfaces at a sulfide ore body, Iron Mountain, California. This iron-oxidizing Archaeon is capable of growth at pH 0. This species represents a dominant prokaryote in the environment studied (slimes and sediments) and constituted up to 85% of the microbial community when solution concentrations were high (conductivity of 100 to 160 millisiemens per centimeter). The presence of this and other closely related Thermoplasmales suggests that these acidophiles are important contributors to acid mine drainage and may substantially impact iron and sulfur cycles. PMID:10710303

  10. Representing ozone extremes in European megacities: the importance of resolution in a global chemistry climate model

    NASA Astrophysics Data System (ADS)

    Stock, Z. S.; Russo, M. R.; Pyle, J. A.

    2014-04-01

    The continuing growth of the world's urban population has led to an increasing number of cities with more than 10 million inhabitants. The higher emissions of pollutants, coupled to higher population density, makes predictions of air quality in these megacities of particular importance from both a science and a policy perspective. Global climate models are typically run at coarse resolution to enable both the efficient running of long time integrations, and the ability to run multiple future climate scenarios. However, when considering surface ozone concentrations at the local scale, coarse resolution can lead to inaccuracies arising from the highly nonlinear ozone chemistry and the sensitivity of ozone to the distribution of its precursors on smaller scales. In this study, we use UM-UKCA, a global atmospheric chemistry model, coupled to the UK Met Office Unified Model, to investigate the impact of model resolution on tropospheric ozone, ranging from global to local scales. We focus on the model's ability to represent the probability of high ozone concentrations in the summer and low ozone concentrations, associated with polluted megacity environments, in the winter, and how this varies with horizontal resolution. We perform time-slice integrations with two model configurations at typical climate resolution (CR, ~150 km) and at a higher resolution (HR, ~40 km). The CR configuration leads to overestimation of ozone concentrations on both regional and local scales, while it gives broadly similar results to the HR configuration on the global scale. The HR configuration is found to produce a more realistic diurnal cycle of ozone concentrations and to give a better representation of the probability density function of ozone values in urban areas such as the megacities of London and Paris. We find the observed differences in model behaviour between CR and HR configurations to be largely caused by chemical differences during the winter and meteorological differences

  11. Representing ozone extremes in European megacities: the importance of resolution in a global chemistry climate model

    NASA Astrophysics Data System (ADS)

    Stock, Z. S.; Russo, M. R.; Pyle, J. A.

    2013-10-01

    The continuing growth of the world's urban population has led to an increasing number of cities with more than 10 million inhabitants. The higher emissions of pollutants, coupled to higher population density, makes predictions of air quality in these megacities of particular importance from both a science and a policy perspective. Global climate models are typically run at coarse resolution to enable both the efficient running of long time integrations, and the ability to run multiple future climate scenarios. However, when considering surface ozone concentrations at the local scale, coarse resolution can lead to inaccuracies arising from the highly non-linear ozone chemistry and the sensitivity of ozone to the distribution of its precursors on smaller scales. In this study, we use UM-UKCA, a global atmospheric chemistry model, coupled to the UK Met Office Unified Model, to investigate the impact of model resolution on tropospheric ozone, ranging from global to local scales. We focus on the model's ability to represent the probability of high ozone concentrations in the summer and low ozone concentrations, associated with polluted megacity environments, in the winter, and how this varies with horizontal resolution. We perform time-slice integrations with two model configurations at typical climate resolution (CR, ~150 km) and at a higher resolution (HR, ~40 km). The CR configuration leads to overestimation of ozone concentrations on both regional and local scales, while it gives broadly similar results to the HR configuration on the global scale. The HR configuration is found to produce a more realistic diurnal cycle of ozone concentrations and to give a better representation of the probability density function of ozone values in urban areas such as the megacities of London and Paris. We discuss the possible causes for the observed difference in model behaviour between CR and HR configurations and estimate the relative contribution of chemical and meteorological

  12. PHASER 2.10 methodology for dependence, importance, and sensitivity: The role of scale factors, confidence factors, and extremes

    SciTech Connect

    Cooper, J.A.

    1996-09-01

    PHASER (Probabilistic Hybrid Analytical System Evaluation Routine) is a software tool that has the capability of incorporating subjective expert judgment into probabilistic safety analysis (PSA) along with conventional data inputs. An earlier report described the PHASER methodology, but only gave a cursory explanation about how dependence was incorporated in Version 1.10 and about how ``Importance`` and ``Sensitivity`` measures were to be incorporated in Version 2.00. A more detailed description is given in this report. The basic concepts involve scale factors and confidence factors that are associated with the stochastic variability and subjective uncertainty (which are common adjuncts used in PSA), and the safety risk extremes that are crucial to safety assessment. These are all utilized to illustrate methodology for incorporating dependence among analysis variables in generating PSA results, and for Importance and Sensitivity measures associated with the results that help point out where any major sources of safety concern arise and where any major sources of uncertainty reside, respectively.

  13. Synthesis of Concepts in Disturbance Hydrology and the Importance for Hydrologic Response to Extreme Hydroclimatic Events in the Critical Zone

    NASA Astrophysics Data System (ADS)

    Ebel, B. A.; Mirus, B. B.

    2014-12-01

    The watersheds we rely on for water resources, ecosystem services, and protection from hydrologically driven natural hazards are increasingly impacted by landscape disturbance. Abrupt alterations of hydrologic processes resulting from wildfires, urban development, resource extraction, deforestation, hurricanes, tsunamis, and landslides change the storage or buffering capacity as well as the hydrologic functional connectivity in watersheds. We highlight some of the critical issues and major challenges to predicting disturbance impacts on water resources and natural hazards and outline some of the opportunities for improved mechanistic understanding of how disturbances propagate through landscape hydrological processes. In particular, we emphasize synthesis of conceptual commonalities and opportunities from other disciplines, primarily ecologic sciences, which are well versed in the study of disturbed landscapes. Cross scale interactions and complex adaptive systems theory are examples of useful concepts for synthesis across different disturbance effects. We also highlight the importance of improved understanding of disturbance hydrology for predicting the effects of extreme hydroclimatic events on the hydrologic response of the Critical Zone. An example from the Front Range of the Rocky Mountains, USA of a watershed with multiple disturbances subjected to a low frequency extreme rainfall event is presented to show the diversity of runoff generation mechanisms and the implications for watershed scale impacts.

  14. On the use of ocean-atmosphere-wave models during an extreme CAO event: the importance of being coupled

    NASA Astrophysics Data System (ADS)

    Carniel, Sandro; Barbariol, Francesco; Benetazzo, Alvise; Bonaldo, Davide; Falcieri, Francesco M.; Miglietta, Mario M.; Ricchi, Antonio; Sclavo, Mauro

    2015-04-01

    During winter 2012 an extreme meteorological event stroke the whole Europe and particularly its central-southern sector. A strong and persistent spit of cold air coming from Siberian region (a Cold Air Outbreak, CAO) insisted on northern Italy and the Adriatic sea basin, leading to decreases in the sea temperatures up to 6 °C in less than two weeks, ice formation on the Venice lagoon and an exceptional snow fall in the Apennine region. In the sea the CAO was associated to a significant episode of dense water formation (DWF), a crucial phenomenon that heavily impacts the whole Adriatic Sea (from the sinking of water masses and associated ventilation of the northernmost shelf, to the flow along the western coast, until the flushing of southern Adriatic open slope and submarine canyons, with associated sediment transport and bottom reshaping). The extent of the DWF event in the Northern Adriatic sub-basin was estimated by means of coastal observatories, ad hoc measurements and, until now, results from existing one-way coupled atmosphere-ocean models. These are characterized by no SST feedback from the ocean to the atmosphere, and therefore by turbulent heat fluxes that may heavily reflect a non-consistent ocean state. The study proposes an investigation of the 2012 CAO using a fully coupled, three components, ocean-atmosphere-wave system (COAWST). Results highlight that, although the energy interplays between air and sea do not seem to significantly impact the wind forecasts, when providing heat fluxes that are consistent with the ocean temperature we find modified heat fluxes and air sea temperatures figures. Moreover, the consistent description of thermal exchanges adopted in the fully coupled model can affect the basin circulation, the quantification of dense water produced mass, and the description of its migration pathways and rates of off-shelf descent.

  15. [Importance of revision- and tumor-endoprosthetics in the treatment of periprosthetic fractures of the lower extremity].

    PubMed

    Prodinger, P M; Harrasser, N; Suren, C; Pohlig, F; Mühlhofer, H; Schauwecker, J; von Eisenhart-Rothe, R

    2016-04-01

    Periprosthetic fractures of hip and knee prostheses are gaining clinical significance due to the increasing numbers of of primary arthroplasties. Additionally, these fractures are often associated with poor bone quality or present in patients after multiple revision procedures and concomitant excessive bone defects precluding those patients to be adequately treated by conventional osteosynthesis. Revision implants provide a wide range of options for the treatment of these fractures in order to achieve good clinical results. In the acetabular region cavitary defects associated with periprosthetic fractures can be treated by the use of megacups. Extensive segmental defects and pelvic discontinuity necessitate the use of cups with additional iliac support or even customized implants. Proximal femoral fractures can usually be fixed with modular stems and diaphyseal anchorage. Periprosthetic knee joint fractures can be treated with revision implants with modular sleeves or augment-combinations allowing sufficient bridging of bony defects. Functional reconstruction or refixation of the extensor mechanism is of crucial importance. PMID:27008214

  16. How extreme are extremes?

    NASA Astrophysics Data System (ADS)

    Cucchi, Marco; Petitta, Marcello; Calmanti, Sandro

    2016-04-01

    High temperatures have an impact on the energy balance of any living organism and on the operational capabilities of critical infrastructures. Heat-wave indicators have been mainly developed with the aim of capturing the potential impacts on specific sectors (agriculture, health, wildfires, transport, power generation and distribution). However, the ability to capture the occurrence of extreme temperature events is an essential property of a multi-hazard extreme climate indicator. Aim of this study is to develop a standardized heat-wave indicator, that can be combined with other indices in order to describe multiple hazards in a single indicator. The proposed approach can be used in order to have a quantified indicator of the strenght of a certain extreme. As a matter of fact, extremes are usually distributed in exponential or exponential-exponential functions and it is difficult to quickly asses how strong was an extreme events considering only its magnitude. The proposed approach simplify the quantitative and qualitative communication of extreme magnitude

  17. The importance of the anterior longitudinal ligament in lumbar disc arthroplasty: 36-Month follow-up experience in extreme lateral total disc replacement

    PubMed Central

    Marchi, Luis; Oliveira, Leonardo; Coutinho, Etevaldo; Pimenta, Luiz

    2012-01-01

    Background Current total disc replacement (TDR) for lumbar spine requires an anterior approach for implantation but presents inherent limitations, including risks to the abdominal structures, as well as resection of the anterior longitudinal ligament. By approaching the spine laterally, it is possible to preserve the stabilizing ligaments, which are a natural restraint to excessive rotations and translations, and thereby help to minimize facet stresses. This less invasive approach also offers a biomechanical advantage of placement of the device over the ring apophysis bilaterally; importantly, it also offers a greater opportunity for safer revision surgery, if necessary, by avoiding scarring of the anterior vasculature. We present the clinical and radiologic results of a lateral TDR device from a prospective single-center study. Methods A new metal-on-metal TDR device designed for implantation through a true lateral, retroperitoneal, transpsoatic approach (extreme lateral interbody fusion) was implanted in 36 patients with discography-confirmed 1- or 2-level degenerative disc disease. Clinical (pain and function) and radiographic (range of motion) outcome assessments were prospectively collected preoperatively, postoperatively, and serially up to a minimum of 36 months’ follow-up. Results Between December 2005 and December 2006, 36 surgeries were performed in 16 men and 20 women (mean age, 42.6 years). These included 15 single-level TDR procedures at L3-4 or L4-5, 3 2-level TDR procedures spanning L3-4 and L4-5, and 18 hybrid procedures (anterior lumbar interbody fusion) at L5-S1 and TDR at L4-5 (17) or L3-4 (1). Operative time averaged 130 minutes, with mean blood loss of 60 mL and no intraoperative complications. Postoperative X-rays showed good device placement, with restoration of disc height, foraminal volume, and sagittal balance. All patients were up and walking within 12 hours of surgery, and all but 9 were discharged the next day (7 of those 9 were

  18. How extreme is extreme hourly precipitation?

    NASA Astrophysics Data System (ADS)

    Papalexiou, Simon Michael; Dialynas, Yannis G.; Pappas, Christoforos

    2016-04-01

    The importance of accurate representation of precipitation at fine time scales (e.g., hourly), directly associated with flash flood events, is crucial in hydrological design and prediction. The upper part of a probability distribution, known as the distribution tail, determines the behavior of extreme events. In general, and loosely speaking, tails can be categorized in two families: the subexponential and the hyperexponential family, with the first generating more intense and more frequent extremes compared to the latter. In past studies, the focus has been mainly on daily precipitation, with the Gamma distribution being the most popular model. Here, we investigate the behaviour of tails of hourly precipitation by comparing the upper part of empirical distributions of thousands of records with three general types of tails corresponding to the Pareto, Lognormal, and Weibull distributions. Specifically, we use thousands of hourly rainfall records from all over the USA. The analysis indicates that heavier-tailed distributions describe better the observed hourly rainfall extremes in comparison to lighter tails. Traditional representations of the marginal distribution of hourly rainfall may significantly deviate from observed behaviours of extremes, with direct implications on hydroclimatic variables modelling and engineering design.

  19. Upper Extremity Amputations and Prosthetics

    PubMed Central

    Ovadia, Steven A.; Askari, Morad

    2015-01-01

    Upper extremity amputations are most frequently indicated by severe traumatic injuries. The location of the injury will determine the level of amputation. Preservation of extremity length is often a goal. The amputation site will have important implications on the functional status of the patient and options for prosthetic reconstruction. Advances in amputation techniques and prosthetic reconstructions promote improved quality of life. In this article, the authors review the principles of upper extremity amputation, including techniques, amputation sites, and prosthetic reconstructions. PMID:25685104

  20. Penetrating extremity trauma.

    PubMed

    Ivatury, Rao R; Anand, Rahul; Ordonez, Carlos

    2015-06-01

    Penetrating extremity trauma (PET) usually becomes less important when present along with multiple truncal injuries. The middle eastern wars documented the terrible mortality and morbidity resulting from PET. Even in civilian trauma, PET can lead to significant morbidity and mortality. There are now well-established principles in the evaluation and management of vascular, bony, soft tissue, and neurologic lesions that will lead to a reduction of the poor outcomes. This review will summarize some of these recent concepts.

  1. Workshop on Extreme Physics

    NASA Astrophysics Data System (ADS)

    Mundell, Carole; Sullivan, Mark

    2012-04-01

    abstract-type="normal">SummaryNever before has there been such a wealth of versatile ground- and space-based facilities with which to detect variable emission across the electromagnetic spectrum and beyond, to non-EM signals such as neutrinos and gravitational waves, to probe the most extreme phenomena in the Universe. The variable sky is already providing a wealth of new and surprising observations of phenomena such as GRBs, SNe and AGN that are pushing current theories beyond the state of the art. Multi-messenger follow-up will soon become de rigeur, and upcoming radio and optical all-sky transient surveys will revolutionise the study of the transient Universe. In addition to the technical and data challenges presented by such surveys, a major new challenge will be the interpretation of the wealth of available data and the identification of the underlying physics of new classes of variable (and potentially exotic) objects. Theoretical predictions will be vital for interpreting these future transient discoveries. The goal of this workshop was to bring together theorists and observers in order to identify unexplored synergies across three main research areas of extreme physics: gamma-ray bursts, supernovæ and, more generically, relativistic jets. It aimed to discuss key outstanding questions in these rapidly moving fields, such as the composition and acceleration of GRB and AGN jets, GRB progenitors and central engines, the origin of the wide range of observed variability time-scales in GRB prompt and after-glow light curves and related cosmological applications, the physics of the newly-discovered ultra-luminous SN-like optical transients-as well as to speculate on what we might hope to discover with future technology. The workshop absorbed two 90-minute sessions, selecting 3 main science topics (Relativistic Jets, GRBs and SNe) which it organised as structured discussions driven by a series of short but provocative questions. The final session featured a panel

  2. Climate Extremes and Society

    NASA Astrophysics Data System (ADS)

    Mote, Philip

    2009-10-01

    In October 2005, as the United States still was reeling from Hurricane Katrina in August and as the alphabet was too short to contain all of that year's named Atlantic tropical storms (Hurricane Wilma was forming near Jamaica), a timely workshop in Bermuda focused on climate extremes and society (see Eos, 87(3), 25, 17 January 2006). This edited volume, which corresponds roughly to the presentations given at that workshop, offers a fascinating look at the critically important intersection of acute climate stress and human vulnerabilities. A changing climate affects humans and other living things not through the variable that most robustly demonstrates the role of rising greenhouse gases—globally averaged temperature—but through local changes, especially changes in extremes. The first part of this book, “Defining and modeling the nature of weather and climate extremes,” focuses on natural science. The second part, “Impacts of weather and climate extremes,” focuses on societal impacts and responses, emphasizing an insurance industry perspective because a primary sponsor of the workshop was the Risk Prediction Initiative, whose aim is to “support scientific research on topics of interest to its sponsors” (p. 320).

  3. Hydrological extremes and security

    NASA Astrophysics Data System (ADS)

    Kundzewicz, Z. W.; Matczak, P.

    2015-04-01

    Economic losses caused by hydrological extremes - floods and droughts - have been on the rise. Hydrological extremes jeopardize human security and impact on societal livelihood and welfare. Security can be generally understood as freedom from threat and the ability of societies to maintain their independent identity and their functional integrity against forces of change. Several dimensions of security are reviewed in the context of hydrological extremes. The traditional interpretation of security, focused on the state military capabilities, has been replaced by a wider understanding, including economic, societal and environmental aspects that get increasing attention. Floods and droughts pose a burden and serious challenges to the state that is responsible for sustaining economic development, and societal and environmental security. The latter can be regarded as the maintenance of ecosystem services, on which a society depends. An important part of it is water security, which can be defined as the availability of an adequate quantity and quality of water for health, livelihoods, ecosystems and production, coupled with an acceptable level of water-related risks to people, environments and economies. Security concerns arise because, over large areas, hydrological extremes - floods and droughts - are becoming more frequent and more severe. In terms of dealing with water-related risks, climate change can increase uncertainties, which makes the state's task to deliver security more difficult and more expensive. However, changes in population size and development, and level of protection, drive exposure to hydrological hazards.

  4. "A discovery! The Higgs? Why is this important? How it was done"

    ScienceCinema

    Sally Dawson; Howard Gordan

    2016-07-12

    Data collected during 2011 and 2012 at the Large Hadron Collider (LHC) at CERN in Switzerland, the world's highest-energy proton collider, has culminated in the discovery of a new particle that is about 135 times heavier than a proton. But is it really the Higgs particle predicted by the theory that explains the origin of the mass of most elementary particles in the universe? The discovery and its possible identity is discussed by two Brookhaven Lab physicists, Sally Dawson and Howard Gordon, with deep roots in the hunt for the Higgs.

  5. "A discovery! The Higgs? Why is this important? How it was done"

    SciTech Connect

    Sally Dawson; Howard Gordan

    2012-06-26

    Data collected during 2011 and 2012 at the Large Hadron Collider (LHC) at CERN in Switzerland, the world's highest-energy proton collider, has culminated in the discovery of a new particle that is about 135 times heavier than a proton. But is it really the Higgs particle predicted by the theory that explains the origin of the mass of most elementary particles in the universe? The discovery and its possible identity is discussed by two Brookhaven Lab physicists, Sally Dawson and Howard Gordon, with deep roots in the hunt for the Higgs.

  6. Modeling extreme risks in ecology.

    PubMed

    Burgman, Mark; Franklin, James; Hayes, Keith R; Hosack, Geoffrey R; Peters, Gareth W; Sisson, Scott A

    2012-11-01

    Extreme risks in ecology are typified by circumstances in which data are sporadic or unavailable, understanding is poor, and decisions are urgently needed. Expert judgments are pervasive and disagreements among experts are commonplace. We outline approaches to evaluating extreme risks in ecology that rely on stochastic simulation, with a particular focus on methods to evaluate the likelihood of extinction and quasi-extinction of threatened species, and the likelihood of establishment and spread of invasive pests. We evaluate the importance of assumptions in these assessments and the potential of some new approaches to account for these uncertainties, including hierarchical estimation procedures and generalized extreme value distributions. We conclude by examining the treatment of consequences in extreme risk analysis in ecology and how expert judgment may better be harnessed to evaluate extreme risks.

  7. Effects of extreme natural events on the provision of ecosystem services in a mountain environment: The importance of trail design in delivering system resilience and ecosystem service co-benefits.

    PubMed

    Tomczyk, Aleksandra M; White, Piran C L; Ewertowski, Marek W

    2016-01-15

    A continued supply of ecosystem services (ES) from a system depends on the resilience of that system to withstand shocks and perturbations. In many parts of the world, climate change is leading to an increased frequency of extreme weather events, potentially influencing ES provision. Our study of the effects of an intense rainfall event in Gorce National Park, Poland, shows: (1) the intense rainfall event impacted heavily on the supply of ES by limiting potential recreation opportunities and reducing erosion prevention; (2) these negative impacts were not only restricted to the period of the extreme event but persisted for up to several years, depending on the pre-event trail conditions and post-event management activities; (3) to restore the pre-event supply of ES, economic investments were required in the form of active repairs to trails, which, in Gorce National Park, were an order of magnitude higher than the costs of normal trail maintenance; and (4) when recreational trails were left to natural restoration, loss of biodiversity was observed, and recovery rates of ES (recreation opportunities and soil erosion prevention) were reduced in comparison to their pre-event state. We conclude that proper trail design and construction provides a good solution to avoid some of the negative impacts of extreme events on recreation, as well as offering co-benefits in terms of protecting biodiversity and enhancing the supply of regulating services such as erosion prevention.

  8. Effects of extreme natural events on the provision of ecosystem services in a mountain environment: The importance of trail design in delivering system resilience and ecosystem service co-benefits.

    PubMed

    Tomczyk, Aleksandra M; White, Piran C L; Ewertowski, Marek W

    2016-01-15

    A continued supply of ecosystem services (ES) from a system depends on the resilience of that system to withstand shocks and perturbations. In many parts of the world, climate change is leading to an increased frequency of extreme weather events, potentially influencing ES provision. Our study of the effects of an intense rainfall event in Gorce National Park, Poland, shows: (1) the intense rainfall event impacted heavily on the supply of ES by limiting potential recreation opportunities and reducing erosion prevention; (2) these negative impacts were not only restricted to the period of the extreme event but persisted for up to several years, depending on the pre-event trail conditions and post-event management activities; (3) to restore the pre-event supply of ES, economic investments were required in the form of active repairs to trails, which, in Gorce National Park, were an order of magnitude higher than the costs of normal trail maintenance; and (4) when recreational trails were left to natural restoration, loss of biodiversity was observed, and recovery rates of ES (recreation opportunities and soil erosion prevention) were reduced in comparison to their pre-event state. We conclude that proper trail design and construction provides a good solution to avoid some of the negative impacts of extreme events on recreation, as well as offering co-benefits in terms of protecting biodiversity and enhancing the supply of regulating services such as erosion prevention. PMID:26496846

  9. Penetrating nontorso trauma: the extremities

    PubMed Central

    Ball, Chad G.

    2015-01-01

    Summary Similar to penetrating torso trauma, nontorso injuries have undergone a fascinating oscillation between invasive and noninvasive approaches. This article discusses an organized approach to the evaluation and initial treatment of penetrating extremity injuries based on regional anatomy and clinical examination. The approach is reliable, efficient and minimizes both delays in diagnosis and missed injuries. Outpatient follow-up is particularly important for patients with extremity injuries who are discharged home from the emergency department. PMID:26022152

  10. [Extreme results in electrolyte determination].

    PubMed

    Vogt, W; Oesterle, B

    1992-01-01

    Besides statistical quality control, quality control based on patient specimens is an important tool for quality enhancement and thus for an increased diagnostic certainty in laboratory medicine. One of three possibilities of plausibility judgement is the control of extreme results, that is alert and absurd value check. The aim of our study was to look for extremely high or low findings of the most frequently examined clinical-chemical parameters, to scrutinize their validity according to clearly defined criteria and to find out the underlying actual clinical situations and diseases. In this publication only the results for the electrolytes are discussed. Retrospectively the most extreme values of all results for serum sodium, potassium and chloride concentrations of a 21-month interval were extracted in a large university hospital. The clinical situation was then evaluated by reading the medical reports of these patients. The validity of the findings was judged by previously defined criteria and rated as confirmed, questionable and not confirmed. In all cases the survival time was determined. The most extreme confirmed results were for sodium 191 and 100 mmol/l, for potassium 9.0 and 1.3 mmol/l and for chloride 138 and 65 mmol/l. All these findings were compatible with life, at least for several hours. Even if it is probably impossible to give generally valid extreme ranges. Nevertheless our results should certainly have practical importance in absurd and alert value check. PMID:1502820

  11. Astrobiology: Life in Extreme Environments

    ERIC Educational Resources Information Center

    Kaur, Preeti

    2011-01-01

    Astrobiology is the study of the origin, evolution and distribution of life in the universe. It seeks to answer two important scientific questions: how did we get here and are we alone in the universe? Scientists begin by studying life on Earth and its limits. The discovery of extremophiles on Earth capable of surviving extremes encourages the…

  12. Extreme Scale Visual Analytics

    SciTech Connect

    Wong, Pak C.; Shen, Han-Wei; Pascucci, Valerio

    2012-05-08

    Extreme-scale visual analytics (VA) is about applying VA to extreme-scale data. The articles in this special issue examine advances related to extreme-scale VA problems, their analytical and computational challenges, and their real-world applications.

  13. Reporting Outcomes of Extremely Preterm Births.

    PubMed

    Rysavy, Matthew A; Marlow, Neil; Doyle, Lex W; Tyson, Jon E; Serenius, Frederik; Iams, Jay D; Stoll, Barbara J; Barrington, Keith J; Bell, Edward F

    2016-09-01

    Published reports of extremely preterm birth outcomes provide important information to families, clinicians, and others and are widely used to make clinical and policy decisions. Misreporting or misunderstanding of outcome reports may have significant consequences. This article presents 7 recommendations to improve reporting of extremely preterm birth outcomes in both the primary and secondary literature. The recommendations should facilitate clarity in communication about extremely preterm birth outcomes and increase the value of existing and future work in this area. PMID:27516525

  14. Extreme, expedition, and wilderness medicine.

    PubMed

    Imray, Christopher H E; Grocott, Michael P W; Wilson, Mark H; Hughes, Amy; Auerbach, Paul S

    2015-12-19

    Extreme, expedition, and wilderness medicine are modern and rapidly evolving specialties that address the spirit of adventure and exploration. The relevance of and interest in these specialties are changing rapidly to match the underlying activities, which include global exploration, adventure travel, and military deployments. Extreme, expedition, and wilderness medicine share themes of providing best available medical care in the outdoors, especially in austere or remote settings. Early clinical and logistics decision making can often have important effects on subsequent outcomes. There are lessons to be learned from out-of-hospital care, military medicine, humanitarian medicine, and disaster medicine that can inform in-hospital medicine, and vice-versa. The future of extreme, expedition, and wilderness medicine will be defined by both recipients and practitioners, and empirical observations will be transformed by evidence-based practice.

  15. Extreme, expedition, and wilderness medicine.

    PubMed

    Imray, Christopher H E; Grocott, Michael P W; Wilson, Mark H; Hughes, Amy; Auerbach, Paul S

    2015-12-19

    Extreme, expedition, and wilderness medicine are modern and rapidly evolving specialties that address the spirit of adventure and exploration. The relevance of and interest in these specialties are changing rapidly to match the underlying activities, which include global exploration, adventure travel, and military deployments. Extreme, expedition, and wilderness medicine share themes of providing best available medical care in the outdoors, especially in austere or remote settings. Early clinical and logistics decision making can often have important effects on subsequent outcomes. There are lessons to be learned from out-of-hospital care, military medicine, humanitarian medicine, and disaster medicine that can inform in-hospital medicine, and vice-versa. The future of extreme, expedition, and wilderness medicine will be defined by both recipients and practitioners, and empirical observations will be transformed by evidence-based practice. PMID:26738718

  16. Controlling extreme events on complex networks

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Zhong; Huang, Zi-Gang; Lai, Ying-Cheng

    2014-08-01

    Extreme events, a type of collective behavior in complex networked dynamical systems, often can have catastrophic consequences. To develop effective strategies to control extreme events is of fundamental importance and practical interest. Utilizing transportation dynamics on complex networks as a prototypical setting, we find that making the network ``mobile'' can effectively suppress extreme events. A striking, resonance-like phenomenon is uncovered, where an optimal degree of mobility exists for which the probability of extreme events is minimized. We derive an analytic theory to understand the mechanism of control at a detailed and quantitative level, and validate the theory numerically. Implications of our finding to current areas such as cybersecurity are discussed.

  17. 21st Birthday Drinking: Extremely Extreme

    ERIC Educational Resources Information Center

    Rutledge, Patricia C.; Park, Aesoon; Sher, Kenneth J.

    2008-01-01

    Despite public recognition of the hazards of 21st birthday drinking, there is little empirical information concerning its prevalence, severity, and risk factors. Data from a sample of 2,518 college students suggest that 21st birthday drinking poses an extreme danger: (a) 4 of every 5 participants (83%) reported drinking to celebrate, (b) birthday…

  18. Are hourly precipitation extremes increasing faster than daily precipitation extremes?

    NASA Astrophysics Data System (ADS)

    Barbero, Renaud; Fowler, Hayley; Blenkinsop, Stephen; Lenderink, Geert

    2016-04-01

    Extreme precipitation events appear to be increasing with climate change in many regions of the world, including the United States. These extreme events have large societal impacts, as seen during the recent Texas-Oklahoma flooding in May 2015 which caused several billion in damages and left 47 deaths in its path. Better understanding of past changes in the characteristics of extreme rainfall events is thus critical for reliable projections of future changes. Although it has been documented in several studies that daily precipitation extremes are increasing across parts of the contiguous United States, very few studies have looked at hourly extremes. However, this is of primary importance as recent studies on the temperature scaling of extreme precipitation have shown that increases above the Clausius-Clapeyron (~ 7% °C‑1) are possible for hourly precipitation. In this study, we used hourly precipitation data (HPD) from the National Climatic Data Center and extracted more than 1,000 stations across the US with more than 40 years of data spanning the period 1950-2010. As hourly measurements are often associated with a range of issues, the data underwent multiple quality control processes to exclude erroneous data. While no significant changes were found in annual maximum precipitation using both hourly and daily resolution datasets, significant increasing trends in terms of frequency of episodes exceeding present-day 95th percentiles of wet hourly/daily precipitation were observed across a significant portion of the US. The fraction of stations with significant increasing trends falls outside the confidence interval range during all seasons but the summer. While less than 12% of stations exhibit significant trends at the daily scale in the wintertime, more than 45% of stations, mostly clustered in central and Northern United States, show significant increasing trends at the hourly scale. This suggests that short-duration storms have increased faster than daily

  19. Are hourly precipitation extremes increasing faster than daily precipitation extremes?

    NASA Astrophysics Data System (ADS)

    Barbero, Renaud; Fowler, Hayley; Blenkinsop, Stephen; Lenderink, Geert

    2016-04-01

    Extreme precipitation events appear to be increasing with climate change in many regions of the world, including the United States. These extreme events have large societal impacts, as seen during the recent Texas-Oklahoma flooding in May 2015 which caused several billion in damages and left 47 deaths in its path. Better understanding of past changes in the characteristics of extreme rainfall events is thus critical for reliable projections of future changes. Although it has been documented in several studies that daily precipitation extremes are increasing across parts of the contiguous United States, very few studies have looked at hourly extremes. However, this is of primary importance as recent studies on the temperature scaling of extreme precipitation have shown that increases above the Clausius-Clapeyron (~ 7% °C-1) are possible for hourly precipitation. In this study, we used hourly precipitation data (HPD) from the National Climatic Data Center and extracted more than 1,000 stations across the US with more than 40 years of data spanning the period 1950-2010. As hourly measurements are often associated with a range of issues, the data underwent multiple quality control processes to exclude erroneous data. While no significant changes were found in annual maximum precipitation using both hourly and daily resolution datasets, significant increasing trends in terms of frequency of episodes exceeding present-day 95th percentiles of wet hourly/daily precipitation were observed across a significant portion of the US. The fraction of stations with significant increasing trends falls outside the confidence interval range during all seasons but the summer. While less than 12% of stations exhibit significant trends at the daily scale in the wintertime, more than 45% of stations, mostly clustered in central and Northern United States, show significant increasing trends at the hourly scale. This suggests that short-duration storms have increased faster than daily

  20. Shear Fractures of Extreme Dynamics

    NASA Astrophysics Data System (ADS)

    Tarasov, Boris

    2016-10-01

    Natural and laboratory observations show that shear ruptures (faults) can propagate with extreme dynamics (up to intersonic rupture velocities) through intact materials and along pre-existing faults with frictional and coherent (bonded) interfaces. The rupture propagation is accompanied by significant fault strength weakening in the rupture head. Although essential for understanding earthquakes, rock mechanics, tribology and fractures, the question of what physical processes determine how that weakening occurs is still unresolved. The general approach today to explain the fault weakening is based upon the strong velocity-weakening friction law according to which the fault strength drops rapidly with slip velocity. Different mechanisms of strength weakening caused by slip velocity have been proposed including thermal effect, high-frequency compressional waves, expansion of pore fluid, macroscopic melting and gel formation. This paper proposes that shear ruptures of extreme dynamics propagating in intact materials and in pre-existing frictional and coherent interfaces are governed by the same recently identified mechanism which is associated with an intensive microcracking process in the rupture tip observed for all types of extreme ruptures. The microcracking process creates, in certain conditions, a special fan-like microstructure shear resistance of which is extremely low (up to an order of magnitude less than the frictional strength). The fan-structure representing the rupture head provides strong interface weakening and causes high slip and rupture velocities. In contrast with the velocity-weakening dependency, this mechanism provides the opposite weakening-velocity effect. The fan-mechanism differs remarkably from all reported earlier mechanisms, and it can provide such important features observed in extreme ruptures as: extreme slip and rupture velocities, high slip velocity without heating, off-fault tensile cracking, transition from crack-like to pulse

  1. Bivariate extreme value distributions

    NASA Technical Reports Server (NTRS)

    Elshamy, M.

    1992-01-01

    In certain engineering applications, such as those occurring in the analyses of ascent structural loads for the Space Transportation System (STS), some of the load variables have a lower bound of zero. Thus, the need for practical models of bivariate extreme value probability distribution functions with lower limits was identified. We discuss the Gumbel models and present practical forms of bivariate extreme probability distributions of Weibull and Frechet types with two parameters. Bivariate extreme value probability distribution functions can be expressed in terms of the marginal extremel distributions and a 'dependence' function subject to certain analytical conditions. Properties of such bivariate extreme distributions, sums and differences of paired extremals, as well as the corresponding forms of conditional distributions, are discussed. Practical estimation techniques are also given.

  2. Characteristics of Extreme Auroral Charging Events

    NASA Technical Reports Server (NTRS)

    Minow, Joseph I.; Willis, Emily; Parker, Linda Neergaard

    2014-01-01

    Today’s presentation describes preliminary results from a study of extreme auroral charging in low Earth orbit. Goal of study is to document characteristics of auroral charging events of importance to spacecraft design, operations, and anomaly investigations.

  3. A Millennial Challenge: Extremism in Uncertain Times

    PubMed Central

    Fiske, Susan T.

    2014-01-01

    This comment highlights the relevance and importance of the uncertainty-extremism topic, both scientifically and societally, identifies common themes, locates this work in a wider scientific and social context, describes what we now know and what we still do not, acknowledges some limitations, foreshadowing future directions, and discusses some potential policy relevance. Common themes emerge around the importance of social justice as sound anti-extremism policy. PMID:24511155

  4. A Millennial Challenge: Extremism in Uncertain Times.

    PubMed

    Fiske, Susan T

    2013-09-01

    This comment highlights the relevance and importance of the uncertainty-extremism topic, both scientifically and societally, identifies common themes, locates this work in a wider scientific and social context, describes what we now know and what we still do not, acknowledges some limitations, foreshadowing future directions, and discusses some potential policy relevance. Common themes emerge around the importance of social justice as sound anti-extremism policy. PMID:24511155

  5. Generalized extreme gust wind speeds distributions

    USGS Publications Warehouse

    Cheng, E.; Yeung, C.

    2002-01-01

    Since summer 1996, the US wind engineers are using the extreme gust (or 3-s gust) as the basic wind speed to quantify the destruction of extreme winds. In order to better understand these destructive wind forces, it is important to know the appropriate representations of these extreme gust wind speeds. Therefore, the purpose of this study is to determine the most suitable extreme value distributions for the annual extreme gust wind speeds recorded in large selected areas. To achieve this objective, we are using the generalized Pareto distribution as the diagnostic tool for determining the types of extreme gust wind speed distributions. The three-parameter generalized extreme value distribution function is, thus, reduced to either Type I Gumbel, Type II Frechet or Type III reverse Weibull distribution function for the annual extreme gust wind speeds recorded at a specific site.With the considerations of the quality and homogeneity of gust wind data collected at more than 750 weather stations throughout the United States, annual extreme gust wind speeds at selected 143 stations in the contiguous United States were used in the study. ?? 2002 Elsevier Science Ltd. All rights reserved.

  6. Extremal surface barriers

    NASA Astrophysics Data System (ADS)

    Engelhardt, Netta; Wall, Aron C.

    2014-03-01

    We present a generic condition for Lorentzian manifolds to have a barrier that limits the reach of boundary-anchored extremal surfaces of arbitrary dimension. We show that any surface with nonpositive extrinsic curvature is a barrier, in the sense that extremal surfaces cannot be continuously deformed past it. Furthermore, the outermost barrier surface has nonnegative extrinsic curvature. Under certain conditions, we show that the existence of trapped surfaces implies a barrier, and conversely. In the context of AdS/CFT, these barriers imply that it is impossible to reconstruct the entire bulk using extremal surfaces. We comment on the implications for the firewall controversy.

  7. Survival of extreme opinions

    NASA Astrophysics Data System (ADS)

    Hsu, Jiann-wien; Huang, Ding-wei

    2009-12-01

    We study the survival of extreme opinions in various processes of consensus formation. All the opinions are treated equally and subjected to the same rules of changing. We investigate three typical models to reach a consensus in each case: (A) personal influence, (B) influence from surroundings, and (C) influence to surroundings. Starting with uniformly distributed random opinions, our calculated results show that the extreme opinions can survive in both models (A) and (B), but not in model (C). We obtain a conclusion that both personal influence and passive adaptation to the environment are not sufficient enough to eradicate all the extreme opinions. Only the active persuasion to change the surroundings eliminates the extreme opinions completely.

  8. Extreme environments and exobiology.

    PubMed

    Friedmann, E I

    1993-01-01

    Ecological research on extreme environments can be applied to exobiological problems such as the question of life on Mars. If life forms (fossil or extant) are found on Mars, their study will help to solve fundamental questions about the nature of life on Earth. Extreme environments that are beyond the range of adaptability of their inhabitants are defined as "absolute extreme". Such environments can serve as terrestrial models for the last stages of life in the history of Mars, when the surface cooled down and atmosphere and water disappeared. The cryptoendolithic microbial community in porous rocks of the Ross Desert in Antarctica and the microbial mats at the bottom of frozen Antarctic lakes are such examples. The microbial communities of Siberian permafrost show that, in frozen but stable communities, long-term survival is possible. In the context of terraforming Mars, selected microorganisms isolated from absolute extreme environments are considered for use in creation of a biological carbon cycle.

  9. Extreme environments and exobiology

    NASA Technical Reports Server (NTRS)

    Friedmann, E. I.

    1993-01-01

    Ecological research on extreme environments can be applied to exobiological problems such as the question of life on Mars. If life forms (fossil or extant) are found on Mars, their study will help to solve fundamental questions about the nature of life on Earth. Extreme environments that are beyond the range of adaptability of their inhabitants are defined as "absolute extreme". Such environments can serve as terrestrial models for the last stages of life in the history of Mars, when the surface cooled down and atmosphere and water disappeared. The cryptoendolithic microbial community in porous rocks of the Ross Desert in Antarctica and the microbial mats at the bottom of frozen Antarctic lakes are such examples. The microbial communities of Siberian permafrost show that, in frozen but stable communities, long-term survival is possible. In the context of terraforming Mars, selected microorganisms isolated from absolute extreme environments are considered for use in creation of a biological carbon cycle.

  10. Analysis of the dependence of extreme rainfalls

    NASA Astrophysics Data System (ADS)

    Padoan, Simone; Ancey, Christophe; Parlange, Marc

    2010-05-01

    The aim of spatial analysis is to quantitatively describe the behavior of environmental phenomena such as precipitation levels, wind speed or daily temperatures. A number of generic approaches to spatial modeling have been developed[1], but these are not necessarily ideal for handling extremal aspects given their focus on mean process levels. The areal modelling of the extremes of a natural process observed at points in space is important in environmental statistics; for example, understanding extremal spatial rainfall is crucial in flood protection. In light of recent concerns over climate change, the use of robust mathematical and statistical methods for such analyses has grown in importance. Multivariate extreme value models and the class of maxstable processes [2] have a similar asymptotic motivation to the univariate Generalized Extreme Value (GEV) distribution , but providing a general approach to modeling extreme processes incorporating temporal or spatial dependence. Statistical methods for max-stable processes and data analyses of practical problems are discussed by [3] and [4]. This work illustrates methods to the statistical modelling of spatial extremes and gives examples of their use by means of a real extremal data analysis of Switzerland precipitation levels. [1] Cressie, N. A. C. (1993). Statistics for Spatial Data. Wiley, New York. [2] de Haan, L and Ferreria A. (2006). Extreme Value Theory An Introduction. Springer, USA. [3] Padoan, S. A., Ribatet, M and Sisson, S. A. (2009). Likelihood-Based Inference for Max-Stable Processes. Journal of the American Statistical Association, Theory & Methods. In press. [4] Davison, A. C. and Gholamrezaee, M. (2009), Geostatistics of extremes. Journal of the Royal Statistical Society, Series B. To appear.

  11. Electronics for Extreme Environments

    NASA Technical Reports Server (NTRS)

    Patel, J. U.; Cressler, J.; Li, Y.; Niu, G.

    2001-01-01

    Most of the NASA missions involve extreme environments comprising radiation and low or high temperatures. Current practice of providing friendly ambient operating environment to electronics costs considerable power and mass (for shielding). Immediate missions such as the Europa orbiter and lander and Mars landers require the electronics to perform reliably in extreme conditions during the most critical part of the mission. Some other missions planned in the future also involve substantial surface activity in terms of measurements, sample collection, penetration through ice and crust and the analysis of samples. Thus it is extremely critical to develop electronics that could reliably operate under extreme space environments. Silicon On Insulator (SOI) technology is an extremely attractive candidate for NASA's future low power and high speed electronic systems because it offers increased transconductance, decreased sub-threshold slope, reduced short channel effects, elimination of kink effect, enhanced low field mobility, and immunity from radiation induced latch-up. A common belief that semiconductor devices function better at low temperatures is generally true for bulk devices but it does not hold true for deep sub-micron SOI CMOS devices with microscopic device features of 0.25 micrometers and smaller. Various temperature sensitive device parameters and device characteristics have recently been reported in the literature. Behavior of state of the art technology devices under such conditions needs to be evaluated in order to determine possible modifications in the device design for better performance and survivability under extreme environments. Here, we present a unique approach of developing electronics for extreme environments to benefit future NASA missions as described above. This will also benefit other long transit/life time missions such as the solar sail and planetary outposts in which electronics is out open in the unshielded space at the ambient space

  12. Extreme Programming: Maestro Style

    NASA Technical Reports Server (NTRS)

    Norris, Jeffrey; Fox, Jason; Rabe, Kenneth; Shu, I-Hsiang; Powell, Mark

    2009-01-01

    "Extreme Programming: Maestro Style" is the name of a computer programming methodology that has evolved as a custom version of a methodology, called extreme programming that has been practiced in the software industry since the late 1990s. The name of this version reflects its origin in the work of the Maestro team at NASA's Jet Propulsion Laboratory that develops software for Mars exploration missions. Extreme programming is oriented toward agile development of software resting on values of simplicity, communication, testing, and aggressiveness. Extreme programming involves use of methods of rapidly building and disseminating institutional knowledge among members of a computer-programming team to give all the members a shared view that matches the view of the customers for whom the software system is to be developed. Extreme programming includes frequent planning by programmers in collaboration with customers, continually examining and rewriting code in striving for the simplest workable software designs, a system metaphor (basically, an abstraction of the system that provides easy-to-remember software-naming conventions and insight into the architecture of the system), programmers working in pairs, adherence to a set of coding standards, collaboration of customers and programmers, frequent verbal communication, frequent releases of software in small increments of development, repeated testing of the developmental software by both programmers and customers, and continuous interaction between the team and the customers. The environment in which the Maestro team works requires the team to quickly adapt to changing needs of its customers. In addition, the team cannot afford to accept unnecessary development risk. Extreme programming enables the Maestro team to remain agile and provide high-quality software and service to its customers. However, several factors in the Maestro environment have made it necessary to modify some of the conventional extreme

  13. Typologies of Extreme Longevity Myths

    PubMed Central

    Young, Robert D.; Desjardins, Bertrand; McLaughlin, Kirsten; Poulain, Michel; Perls, Thomas T.

    2010-01-01

    Purpose. Political, national, religious, and other motivations have led the media and even scientists to errantly accept extreme longevity claims prima facie. We describe various causes of false claims of extraordinary longevity. Design and Methods. American Social Security Death Index files for the period 1980–2009 were queried for individuals with birth and death dates yielding ages 110+ years of age. Frequency was compared to a list of age-validated supercentenarians maintained by the Gerontology Research Group who died during the same time period. Age claims of 110+ years and the age validation experiences of the authors facilitated a list of typologies of false age claims. Results. Invalid age claim rates increase with age from 65% at age 110-111 to 98% by age 115 to 100% for 120+ years. Eleven typologies of false claims were: Religious Authority Myth, Village Elder Myth, Fountain of Youth Myth (substance), Shangri-La Myth (geographic), Nationalist Pride, Spiritual Practice, Familial Longevity, Individual and/or Family Notoriety, Military Service, Administrative Entry Error, and Pension-Social Entitlement Fraud. Conclusions. Understanding various causes of false extreme age claims is important for placing current, past, and future extreme longevity claims in context and for providing a necessary level of skepticism. PMID:21461047

  14. Extremely high latitude auroras

    NASA Astrophysics Data System (ADS)

    Gussenhoven, M. S.

    1982-04-01

    It is pointed out that imaging devices on the polar orbiting ISIS and Defense Meteorological Satellite Program (DMSP) satellites have greatly increased the extent of polar cap and auroral zone coverage and have prompted several studies of polar cap arcs. A description is presented of a statistical study of the occurrence conditions for arcs recorded in DMSP images at extremely high latitudes, taking into account corrected geomagnetic latitudes equal to or greater than 80 deg. The 80 deg boundary is chosen to minimize the problems associated with defining a polar cap boundary. Attention is given to the data base and categorization of extremely high latitude auroras, the relationship to magnetic activity, and the relationship to solar wind conditions. It is found that one category of extremely high latitude auroras is distinctly different from the rest. This category includes the oval auroras which expand poleward in the midnight sector.

  15. Extremal entanglement witnesses

    NASA Astrophysics Data System (ADS)

    Hansen, Leif Ove; Hauge, Andreas; Myrheim, Jan; Sollid, Per Øyvind

    2015-02-01

    We present a study of extremal entanglement witnesses on a bipartite composite quantum system. We define the cone of witnesses as the dual of the set of separable density matrices, thus TrΩρ≥0 when Ω is a witness and ρ is a pure product state, ρ=ψψ† with ψ=ϕ⊗χ. The set of witnesses of unit trace is a compact convex set, uniquely defined by its extremal points. The expectation value f(ϕ,χ)=TrΩρ as a function of vectors ϕ and χ is a positive semidefinite biquadratic form. Every zero of f(ϕ,χ) imposes strong real-linear constraints on f and Ω. The real and symmetric Hessian matrix at the zero must be positive semidefinite. Its eigenvectors with zero eigenvalue, if such exist, we call Hessian zeros. A zero of f(ϕ,χ) is quadratic if it has no Hessian zeros, otherwise it is quartic. We call a witness quadratic if it has only quadratic zeros, and quartic if it has at least one quartic zero. A main result we prove is that a witness is extremal if and only if no other witness has the same, or a larger, set of zeros and Hessian zeros. A quadratic extremal witness has a minimum number of isolated zeros depending on dimensions. If a witness is not extremal, then the constraints defined by its zeros and Hessian zeros determine all directions in which we may search for witnesses having more zeros or Hessian zeros. A finite number of iterated searches in random directions, by numerical methods, leads to an extremal witness which is nearly always quadratic and has the minimum number of zeros. We discuss briefly some topics related to extremal witnesses, in particular the relation between the facial structures of the dual sets of witnesses and separable states. We discuss the relation between extremality and optimality of witnesses, and a conjecture of separability of the so-called structural physical approximation (SPA) of an optimal witness. Finally, we discuss how to treat the entanglement witnesses on a complex Hilbert space as a subset of the

  16. Adventure and Extreme Sports.

    PubMed

    Gomez, Andrew Thomas; Rao, Ashwin

    2016-03-01

    Adventure and extreme sports often involve unpredictable and inhospitable environments, high velocities, and stunts. These activities vary widely and include sports like BASE jumping, snowboarding, kayaking, and surfing. Increasing interest and participation in adventure and extreme sports warrants understanding by clinicians to facilitate prevention, identification, and treatment of injuries unique to each sport. This article covers alpine skiing and snowboarding, skateboarding, surfing, bungee jumping, BASE jumping, and whitewater sports with emphasis on epidemiology, demographics, general injury mechanisms, specific injuries, chronic injuries, fatality data, and prevention. Overall, most injuries are related to overuse, trauma, and environmental or microbial exposure.

  17. Extreme field science

    NASA Astrophysics Data System (ADS)

    Bulanov, S. V.; Esirkepov, T. Zh; Hayashi, Y.; Kando, M.; Kiriyama, H.; Koga, J. K.; Kondo, K.; Kotaki, H.; Pirozhkov, A. S.; Bulanov, S. S.; Zhidkov, A. G.; Rosanov, N. N.; Chen, P.; Neely, D.; Kato, Y.; Narozhny, N. B.; Korn, G.

    2011-12-01

    We discuss the progress in the development of extreme light sources that will open new horizons for studying a wide range of fundamental science and astrophysics problems. The regimes of dominant radiation reaction, which completely change the electromagnetic wave-matter interaction, will be revealed, resulting in a new extremely powerful source of ultrashort high-brightness gamma-ray pulses. The possibility of abundant electron-positron pair creation via multi-photon processes and the possibility of reaching the critical field of quantum electrodynamics, which would lead to vacuum polarization and breakdown, are attracting considerable attention.

  18. Lower extremity orthoses.

    PubMed

    Bogucki, Artur

    2002-01-31

    This article presents the medical indications and contemporary technical capabilities in orthotic management of lower extremity. The classification included typical orthoses as well as devices that today constitute an integral part of modern therapeutic procedures are presented. Therapeutic success is conditioned by professional team-work of the physician, the therapist, the orthotic technician and the patient. PMID:17679908

  19. Lower extremity prostheses.

    PubMed

    Bogucki, A

    2001-01-01

    This article discusses the technical and medical difficulties involved in the proper fitting of prostheses on the lower extremity. The factors determining the success of a prosthesis include the quality of the stump, the skill of prosthesis socket fabrication, and the proper ordering of components, as well as rehabilitation supervised by experts and professional care for the amputee. PMID:17984917

  20. Book review: New concepts and discoveries: the Geological Society of Nevada 2015 Symposium Proceedings

    USGS Publications Warehouse

    Day, Warren C.

    2016-01-01

    The Nevada Geological Society has a long history of convening meetings and workshops focused on the geology and metallogeny of the western United States relevant to the mineral exploration and mining community across the Great Basin. One outgrowth of the Geological Society of Nevada’s 2015 Symposium is a two-volume set, edited by W.M. Pennell and L.J. Garside, entitled New Concepts and Discoveries. The symposium was held in Sparks, Nevada, May 14–23, 2015, with more than 1,000 attendees, 59 talks in 10 thematic sessions, 7 field trips, and 10 short courses, all focused on serving the geologic, exploration, and mining community. The attractively produced, hardbound, two-volume set includes a CD-ROM containing all the manuscripts as well as numerous abstracts from presentations arranged by the thematic session in which they were presented. The papers range from detailed case study descriptions of individual deposits to important syntheses covering the geologic evolution and resulting metallogeny of the Great Basin and beyond.

  1. Climate extremes and the carbon cycle (Invited)

    NASA Astrophysics Data System (ADS)

    Reichstein, M.; Bahn, M.; Ciais, P.; Mahecha, M. D.; Seneviratne, S. I.; Zscheischler, J.

    2013-12-01

    The terrestrial biosphere is a key component of the global carbon cycle and its carbon balance is strongly influenced by climate. Ongoing environmental changes are thought to increase global terrestrial carbon uptake. But evidence is mounting that rare climate extremes can lead to a decrease in ecosystem carbon stocks and therefore have the potential to negate the expected increase in terrestrial carbon uptake. Here we explore the mechanisms and impacts of climate extremes on the terrestrial carbon cycle, and propose a pathway to improve our understanding of present and future impacts of climate extremes on the terrestrial carbon budget. In addition to direct impact on the carbon fluxes of photosynthesis and respiration via extreme temperature and (or) drought, effects of extreme events may also lead to lagged responses, such as wildfires triggered by heat waves and droughts, or pest and pathogen outbreaks following wind-throw caused by heavy storms, reduced plant health due to drought stress or due to less frequent cold extremes in presently cold regions. One extreme event can potentially override accumulated previous carbon sinks, as shown by the Western European 2003 heat wave.. Extreme events have the potential to affect the terrestrial ecosystem carbon balance through a single factor, or as a combination of factors. Climate extremes can cause carbon losses from accumulated stocks, as well as long-lasting impacts on (e.g. lagged effects) on plant growth and mortality, extending beyond the duration of the extreme event itself. The sensitivity of terrestrial ecosystems and their carbon balance to climate change and extreme events varies according to the type of extreme, the climatic region, the land cover, and the land management. Extreme event impacts are very relevant in forests due to the importance of lagged and memory effects on tree growth and mortality, the longevity of tree species, the large forest carbon stocks and their vulnerability, as well as the

  2. Extreme weather events and infectious disease outbreaks

    PubMed Central

    McMichael, Anthony J

    2015-01-01

    Human-driven climatic changes will fundamentally influence patterns of human health, including infectious disease clusters and epidemics following extreme weather events. Extreme weather events are projected to increase further with the advance of human-driven climate change. Both recent and historical experiences indicate that infectious disease outbreaks very often follow extreme weather events, as microbes, vectors and reservoir animal hosts exploit the disrupted social and environmental conditions of extreme weather events. This review article examines infectious disease risks associated with extreme weather events; it draws on recent experiences including Hurricane Katrina in 2005 and the 2010 Pakistan mega-floods, and historical examples from previous centuries of epidemics and ‘pestilence’ associated with extreme weather disasters and climatic changes. A fuller understanding of climatic change, the precursors and triggers of extreme weather events and health consequences is needed in order to anticipate and respond to the infectious disease risks associated with human-driven climate change. Post-event risks to human health can be constrained, nonetheless, by reducing background rates of persistent infection, preparatory action such as coordinated disease surveillance and vaccination coverage, and strengthened disaster response. In the face of changing climate and weather conditions, it is critically important to think in ecological terms about the determinants of health, disease and death in human populations. PMID:26168924

  3. Extreme weather events and infectious disease outbreaks.

    PubMed

    McMichael, Anthony J

    2015-01-01

    Human-driven climatic changes will fundamentally influence patterns of human health, including infectious disease clusters and epidemics following extreme weather events. Extreme weather events are projected to increase further with the advance of human-driven climate change. Both recent and historical experiences indicate that infectious disease outbreaks very often follow extreme weather events, as microbes, vectors and reservoir animal hosts exploit the disrupted social and environmental conditions of extreme weather events. This review article examines infectious disease risks associated with extreme weather events; it draws on recent experiences including Hurricane Katrina in 2005 and the 2010 Pakistan mega-floods, and historical examples from previous centuries of epidemics and 'pestilence' associated with extreme weather disasters and climatic changes. A fuller understanding of climatic change, the precursors and triggers of extreme weather events and health consequences is needed in order to anticipate and respond to the infectious disease risks associated with human-driven climate change. Post-event risks to human health can be constrained, nonetheless, by reducing background rates of persistent infection, preparatory action such as coordinated disease surveillance and vaccination coverage, and strengthened disaster response. In the face of changing climate and weather conditions, it is critically important to think in ecological terms about the determinants of health, disease and death in human populations. PMID:26168924

  4. Extreme weather events and infectious disease outbreaks.

    PubMed

    McMichael, Anthony J

    2015-01-01

    Human-driven climatic changes will fundamentally influence patterns of human health, including infectious disease clusters and epidemics following extreme weather events. Extreme weather events are projected to increase further with the advance of human-driven climate change. Both recent and historical experiences indicate that infectious disease outbreaks very often follow extreme weather events, as microbes, vectors and reservoir animal hosts exploit the disrupted social and environmental conditions of extreme weather events. This review article examines infectious disease risks associated with extreme weather events; it draws on recent experiences including Hurricane Katrina in 2005 and the 2010 Pakistan mega-floods, and historical examples from previous centuries of epidemics and 'pestilence' associated with extreme weather disasters and climatic changes. A fuller understanding of climatic change, the precursors and triggers of extreme weather events and health consequences is needed in order to anticipate and respond to the infectious disease risks associated with human-driven climate change. Post-event risks to human health can be constrained, nonetheless, by reducing background rates of persistent infection, preparatory action such as coordinated disease surveillance and vaccination coverage, and strengthened disaster response. In the face of changing climate and weather conditions, it is critically important to think in ecological terms about the determinants of health, disease and death in human populations.

  5. THE EXTREME HOSTS OF EXTREME SUPERNOVAE

    SciTech Connect

    Neill, James D.; Quimby, Robert; Ofek, Eran; Wyder, Ted K.; Martin, D. Christopher; Barlow, Tom A.; Foster, Karl; Friedman, Peter G.; Morrissey, Patrick; Sullivan, Mark; Gal-Yam, Avishay; Howell, D. Andrew; Nugent, Peter; Seibert, Mark; Overzier, Roderik; Neff, Susan G.; Schiminovich, David; Bianchi, Luciana; Donas, Jose; Heckman, Timothy M.

    2011-01-20

    We use GALEX ultraviolet (UV) and optical integrated photometry of the hosts of 17 luminous supernovae (LSNe, having peak M{sub V} < -21) and compare them to a sample of 26, 000 galaxies from a cross-match between the SDSS DR4 spectral catalog and GALEX interim release 1.1. We place the LSN hosts on the galaxy NUV - r versus M{sub r} color-magnitude diagram (CMD) with the larger sample to illustrate how extreme they are. The LSN hosts appear to favor low-density regions of the galaxy CMD falling on the blue edge of the blue cloud toward the low-luminosity end. From the UV-optical photometry, we estimate the star formation history of the LSN hosts. The hosts have moderately low star formation rates (SFRs) and low stellar masses (M{sub *}) resulting in high specific star formation rates (sSFR). Compared with the larger sample, the LSN hosts occupy low-density regions of a diagram plotting sSFR versus M{sub *} in the area having higher sSFR and lower M{sub *}. This preference for low M{sub *}, high sSFR hosts implies that the LSNe are produced by an effect having to do with their local environment. The correlation of mass with metallicity suggests that perhaps wind-driven mass loss is the factor that prevents LSNe from arising in higher-mass, higher-metallicity hosts. The massive progenitors of the LSNe (>100 M{sub sun}), by appearing in low-SFR hosts, are potential tests for theories of the initial mass function that limit the maximum mass of a star based on the SFR.

  6. Important plasma problems in astrophysics

    SciTech Connect

    Kulsrud, R.M.

    1995-01-01

    In astrophysics, plasmas occur under very extreme conditions. For example there are ultra strong magnetic fields in neutron stars) relativistic plasmas around black holes and in jets, extremely energetic particles such as cosmic rays in the interstellar medium, extremely dense plasmas in accretion disks, and extremely large magnetic Reynold`s numbers in the interstellar medium. These extreme limits for astrophysical plasmas make plasma phenomena much simpler to analyze in astrophysics than in the laboratory. An understanding of such phenomena often results in an interesting way, by simply taking the extreme limiting case of a known plasma theory. I will describe one of the more exciting examples. I will attempt to convey the excitement I felt when I was first exposed to it. However, not all plasma astrophysical phenomena are so simple. There are certain important plasma phenomena in astrophysics, which have not been so easily resolved. In fact a resolution of them is blocking significant progress in astrophysical research. They have not yet yielded to attacks by theoretical astrophysicists nor to extensive numerical simulation. I will attempt to describe one of the more important of these plasma-astrophysical problems, and discuss why its resolution is so important to astrophysics. This significant example is fast, magnetic reconnection. Another significant example is the large-magnetic-Reynold`s-number MHD dynamos.

  7. Controlling extreme events on complex networks.

    PubMed

    Chen, Yu-Zhong; Huang, Zi-Gang; Lai, Ying-Cheng

    2014-01-01

    Extreme events, a type of collective behavior in complex networked dynamical systems, often can have catastrophic consequences. To develop effective strategies to control extreme events is of fundamental importance and practical interest. Utilizing transportation dynamics on complex networks as a prototypical setting, we find that making the network "mobile" can effectively suppress extreme events. A striking, resonance-like phenomenon is uncovered, where an optimal degree of mobility exists for which the probability of extreme events is minimized. We derive an analytic theory to understand the mechanism of control at a detailed and quantitative level, and validate the theory numerically. Implications of our finding to current areas such as cybersecurity are discussed. PMID:25131344

  8. Controlling extreme events on complex networks

    PubMed Central

    Chen, Yu-Zhong; Huang, Zi-Gang; Lai, Ying-Cheng

    2014-01-01

    Extreme events, a type of collective behavior in complex networked dynamical systems, often can have catastrophic consequences. To develop effective strategies to control extreme events is of fundamental importance and practical interest. Utilizing transportation dynamics on complex networks as a prototypical setting, we find that making the network “mobile” can effectively suppress extreme events. A striking, resonance-like phenomenon is uncovered, where an optimal degree of mobility exists for which the probability of extreme events is minimized. We derive an analytic theory to understand the mechanism of control at a detailed and quantitative level, and validate the theory numerically. Implications of our finding to current areas such as cybersecurity are discussed. PMID:25131344

  9. Extreme space weather studies: Addressing societal needs

    NASA Astrophysics Data System (ADS)

    Ngwira, C. M.

    2014-12-01

    Extreme space weather events can adversely impact the operations of critical modern-day technological infrastructure such as high-voltage electric power transmission grids. Understanding of coupled magnetosphere-ionosphere dynamics under extreme solar wind driving conditions is still a major challenge mainly because of a lack of data during such time intervals. This presentation will highlight some of the past and on-going investigations on extreme space weather events, and how these investigations are used to address societal needs. Particularly, I will describe how first principles physics-based 3-D global MHD models are playing a major role in advancing our knowledge on extreme geomagnetically induced currents. These MHD models represent a very important component of attempts to understand the response of the magnetosphere-ionosphere system to varying solar wind conditions.

  10. Extremal quantum cloning machines

    SciTech Connect

    Chiribella, G.; D'Ariano, G. M.; Perinotti, P.; Cerf, N.J.

    2005-10-15

    We investigate the problem of cloning a set of states that is invariant under the action of an irreducible group representation. We then characterize the cloners that are extremal in the convex set of group covariant cloning machines, among which one can restrict the search for optimal cloners. For a set of states that is invariant under the discrete Weyl-Heisenberg group, we show that all extremal cloners can be unitarily realized using the so-called double-Bell states, whence providing a general proof of the popular ansatz used in the literature for finding optimal cloners in a variety of settings. Our result can also be generalized to continuous-variable optimal cloning in infinite dimensions, where the covariance group is the customary Weyl-Heisenberg group of displacement000.

  11. Tibetans at extreme altitude.

    PubMed

    Wu, Tianyi; Li, Shupin; Ward, Michal P

    2005-01-01

    Between 1960 and 2003, 13 Chinese expeditions successfully reached the summit of Chomolungma (Mt Everest or Sagarmatha). Forty-five of the 80 summiteers were Tibetan highlanders. During these and other high-altitude expeditions in Tibet, a series of medical and physiological investigations were carried out on the Tibetan mountaineers. The results suggest that these individuals are better adapted to high altitude and that, at altitude, they have a greater physical capacity than Han (ethnic Chinese) lowland newcomers. They have higher maximal oxygen uptake, greater ventilation, more brisk hypoxic ventilatory responses, larger lung volumes, greater diffusing capacities, and a better quality of sleep. Tibetans also have a lower incidence of acute mountain sickness and less body weight loss. These differences appear to represent genetic adaptations and are obviously significant for humans at extreme altitude. This paper reviews what is known about the physiologic responses of Tibetans at extreme altitudes.

  12. On extreme geomagnetic storms

    NASA Astrophysics Data System (ADS)

    Cid, Consuelo; Palacios, Judith; Saiz, Elena; Guerrero, Antonio; Cerrato, Yolanda

    2014-10-01

    Extreme geomagnetic storms are considered as one of the major natural hazards for technology-dependent society. Geomagnetic field disturbances can disrupt the operation of critical infrastructures relying on space-based assets, and can also result in terrestrial effects, such as the Quebec electrical disruption in 1989. Forecasting potential hazards is a matter of high priority, but considering large flares as the only criterion for early-warning systems has demonstrated to release a large amount of false alarms and misses. Moreover, the quantification of the severity of the geomagnetic disturbance at the terrestrial surface using indices as Dst cannot be considered as the best approach to give account of the damage in utilities. High temporal resolution local indices come out as a possible solution to this issue, as disturbances recorded at the terrestrial surface differ largely both in latitude and longitude. The recovery phase of extreme storms presents also some peculiar features which make it different from other less intense storms. This paper goes through all these issues related to extreme storms by analysing a few events, highlighting the March 1989 storm, related to the Quebec blackout, and the October 2003 event, when several transformers burnt out in South Africa.

  13. Microbial diversity of extreme habitats in human homes.

    PubMed

    Savage, Amy M; Hills, Justin; Driscoll, Katherine; Fergus, Daniel J; Grunden, Amy M; Dunn, Robert R

    2016-01-01

    High-throughput sequencing techniques have opened up the world of microbial diversity to scientists, and a flurry of studies in the most remote and extreme habitats on earth have begun to elucidate the key roles of microbes in ecosystems with extreme conditions. These same environmental extremes can also be found closer to humans, even in our homes. Here, we used high-throughput sequencing techniques to assess bacterial and archaeal diversity in the extreme environments inside human homes (e.g., dishwashers, hot water heaters, washing machine bleach reservoirs, etc.). We focused on habitats in the home with extreme temperature, pH, and chemical environmental conditions. We found a lower diversity of microbes in these extreme home environments compared to less extreme habitats in the home. However, we were nonetheless able to detect sequences from a relatively diverse array of bacteria and archaea. Habitats with extreme temperatures alone appeared to be able to support a greater diversity of microbes than habitats with extreme pH or extreme chemical environments alone. Microbial diversity was lowest when habitats had both extreme temperature and one of these other extremes. In habitats with both extreme temperatures and extreme pH, taxa with known associations with extreme conditions dominated. Our findings highlight the importance of examining interactive effects of multiple environmental extremes on microbial communities. Inasmuch as taxa from extreme environments can be both beneficial and harmful to humans, our findings also suggest future work to understand both the threats and opportunities posed by the life in these habitats. PMID:27672493

  14. Microbial diversity of extreme habitats in human homes

    PubMed Central

    Hills, Justin; Driscoll, Katherine; Fergus, Daniel J.; Grunden, Amy M.; Dunn, Robert R.

    2016-01-01

    High-throughput sequencing techniques have opened up the world of microbial diversity to scientists, and a flurry of studies in the most remote and extreme habitats on earth have begun to elucidate the key roles of microbes in ecosystems with extreme conditions. These same environmental extremes can also be found closer to humans, even in our homes. Here, we used high-throughput sequencing techniques to assess bacterial and archaeal diversity in the extreme environments inside human homes (e.g., dishwashers, hot water heaters, washing machine bleach reservoirs, etc.). We focused on habitats in the home with extreme temperature, pH, and chemical environmental conditions. We found a lower diversity of microbes in these extreme home environments compared to less extreme habitats in the home. However, we were nonetheless able to detect sequences from a relatively diverse array of bacteria and archaea. Habitats with extreme temperatures alone appeared to be able to support a greater diversity of microbes than habitats with extreme pH or extreme chemical environments alone. Microbial diversity was lowest when habitats had both extreme temperature and one of these other extremes. In habitats with both extreme temperatures and extreme pH, taxa with known associations with extreme conditions dominated. Our findings highlight the importance of examining interactive effects of multiple environmental extremes on microbial communities. Inasmuch as taxa from extreme environments can be both beneficial and harmful to humans, our findings also suggest future work to understand both the threats and opportunities posed by the life in these habitats. PMID:27672493

  15. Microbial diversity of extreme habitats in human homes

    PubMed Central

    Hills, Justin; Driscoll, Katherine; Fergus, Daniel J.; Grunden, Amy M.; Dunn, Robert R.

    2016-01-01

    High-throughput sequencing techniques have opened up the world of microbial diversity to scientists, and a flurry of studies in the most remote and extreme habitats on earth have begun to elucidate the key roles of microbes in ecosystems with extreme conditions. These same environmental extremes can also be found closer to humans, even in our homes. Here, we used high-throughput sequencing techniques to assess bacterial and archaeal diversity in the extreme environments inside human homes (e.g., dishwashers, hot water heaters, washing machine bleach reservoirs, etc.). We focused on habitats in the home with extreme temperature, pH, and chemical environmental conditions. We found a lower diversity of microbes in these extreme home environments compared to less extreme habitats in the home. However, we were nonetheless able to detect sequences from a relatively diverse array of bacteria and archaea. Habitats with extreme temperatures alone appeared to be able to support a greater diversity of microbes than habitats with extreme pH or extreme chemical environments alone. Microbial diversity was lowest when habitats had both extreme temperature and one of these other extremes. In habitats with both extreme temperatures and extreme pH, taxa with known associations with extreme conditions dominated. Our findings highlight the importance of examining interactive effects of multiple environmental extremes on microbial communities. Inasmuch as taxa from extreme environments can be both beneficial and harmful to humans, our findings also suggest future work to understand both the threats and opportunities posed by the life in these habitats.

  16. Extreme wind turbine response during operation

    NASA Astrophysics Data System (ADS)

    Sørensen, John D.; Nielsen, Søren R. K.

    2007-07-01

    Estimation of extreme response values is very important for structural design of wind turbines. Due to the influence of control system and nonlinear structural behavior the extreme response is usually assessed based on simulation of turbulence time series. In this paper the problem of statistical load extrapolation is considered using techniques from structural reliability theory. Different simulation techniques to estimate extreme response characteristics are described and compared, including crude Monte Carlo simulation, Importance Sampling, and splitting methods such as the Russian Roulette and the Double and Clump algorithm. A statistically consistent technique is described for including statistical uncertainty and assessing the extreme 50-year response using simulated time series and conditioned on the model parameters. The peak over threshold method together with the Maximum Likelihood Method provides a tool to obtain consistent estimates incl. the statistical uncertainty. An illustrative example indicates that the statistical uncertainty is important compared to the coefficient of variation of the extreme response when the number of 10 minutes simulations at each mean wind speed is limited to 10.

  17. Conditional simulations for fields of extreme precipitation

    NASA Astrophysics Data System (ADS)

    Bechler, Aurélien; Vrac, Mathieu; Bel, Liliane

    2014-05-01

    Many environmental models, such as hydrological models, require input data, e.g. precipitation values, correctly simulated and distributed, even at locations where no observation is available. This is particularly true for extreme events that may be of high importance for impact studies. The last decade has seen max-stable processes emerge as a powerful tool for the statistical modeling of spatial extremes. Recently, such processes have been used in climate context to perform simulations at ungauged sites based on empirical distributions of a spatial field conditioned by observed values in some locations. In this work conditional simulations of extremal t process are investigated, taking benefits of its spectral construction. The methodology of conditional simulations proposed by Dombry et al. [2013] for Brown-Resnick and Schlather models is adapted for the extremal t process with some improvements which enlarge the possible number of conditional points. A simulation study enables to highlight the role of the different parameters of the model and to emphasize the importance of the steps of the algorithm. In this work, we focus on the French Mediterranean basin, which is a key spot of occurrences of meteorological extremes such as heavy precipitation. Indeed, major extreme precipitation are regularly observed in this region near the 'cévenol" mountains. The modeling and the understanding of these extreme precipitation - the so-called 'cévenol events" - are of major importance for hydrological studies in this complex terrain since they often trigger major floods in this region. The application of our methodology on real data in this region shows that the model and the algorithm perform well provided the stationary assumptions are fulfilled.

  18. MicroRNA in neurodegenerative drug discovery: the way forward?

    PubMed

    Campbell, Kristyn; Booth, Stephanie A

    2015-01-01

    Neurodegenerative diseases occur when neuronal cells in the brain or spinal cord progressively lose function and eventually die. Pathological analysis of these tissues reveals changes that include the loss of synapses, tangles of misfolded protein and immune cell activation, even during very early stages of disease well before debilitating clinical signs are apparent. This suggests that if neurodegeneration is treated early enough, drugs designed to delay the progress of these diseases by either repairing the early damage and loss of neurons, or protecting neuron functionality from further insult, may be efficacious. MicroRNAs (miRNAs) are small non-coding RNAs that can post-transcriptionally regulate gene expression. They are particularly numerous within neurons where many are expressed with high specificity, which suggests that they have important roles in the healthy brain. Indeed, miRNAs are essential for the post-mitotic survival of neurons, implying a crucial role in survival and neuroprotection. This has focused attention on exploring the use of miRNA-based drugs as a means to correct cellular abnormalities and maintain neuronal function in neurodegenerative diseases. These efforts are spurred on by the rapid progress to clinical trials for a number of miRNA-based therapies for other diseases such as cardiovascular diseases, fibrosis and cancer.

  19. Acclimatization and tolerance to extreme altitude

    NASA Technical Reports Server (NTRS)

    West, J. B.

    1993-01-01

    During the last ten years, two major experiments have elucidated the factors determining acclimatization and tolerance to extreme altitude (over 7000 m). These were the American Medical Research Expedition to Everest, and the low pressure chamber simulation, Operation Everest II. Extreme hyperventilation is one of the most important responses to extreme altitude. Its chief value is that it allows the climber to maintain an alveolar PO2 which keeps the arterial PO2 above dangerously low levels. Even so, there is evidence of residual impairment of central nervous system function after ascents to extreme altitude, and maximal oxygen consumption falls precipitously above 7000 m. The term 'acclimatization' is probably not appropriate for altitudes above 8000 m, because the body steadily deteriorates at these altitudes. Tolerance to extreme altitude is critically dependent on barometric pressure, and even seasonal changes in pressure probably affect climbing performance near the summit of Mt Everest. Supplementary oxygen always improves exercise tolerance at extreme altitudes, and rescue oxygen should be available on climbing expeditions to 8000 m peaks.

  20. Metagenomics of extreme environments.

    PubMed

    Cowan, D A; Ramond, J-B; Makhalanyane, T P; De Maayer, P

    2015-06-01

    Whether they are exposed to extremes of heat or cold, or buried deep beneath the Earth's surface, microorganisms have an uncanny ability to survive under these conditions. This ability to survive has fascinated scientists for nearly a century, but the recent development of metagenomics and 'omics' tools has allowed us to make huge leaps in understanding the remarkable complexity and versatility of extremophile communities. Here, in the context of the recently developed metagenomic tools, we discuss recent research on the community composition, adaptive strategies and biological functions of extremophiles. PMID:26048196

  1. Upper extremity golf injuries.

    PubMed

    Cohn, Michael A; Lee, Steven K; Strauss, Eric J

    2013-01-01

    Golf is a global sport enjoyed by an estimated 60 million people around the world. Despite the common misconception that the risk of injury during the play of golf is minimal, golfers are subject to a myriad of potential pathologies. While the majority of injuries in golf are attributable to overuse, acute traumatic injuries can also occur. As the body's direct link to the golf club, the upper extremities are especially prone to injury. A thorough appreciation of the risk factors and patterns of injury will afford accurate diagnosis, treatment, and prevention of further injury.

  2. Mineralogy under extreme conditions

    SciTech Connect

    Shu, Jinfu

    2012-02-07

    We have performed measurements of minerals based on the synchrotron source for single crystal and powder X-ray diffraction, inelastic scattering, spectroscopy and radiography by using diamond anvil cells. We investigated the properties of iron (Fe), iron-magnesium oxides (Fe, Mg)O, silica(SiO{sub 2}), iron-magnesium silicates (Fe, Mg)SiO{sub 3} under simulated high pressure-high temperature extreme conditions of the Earth's crust, upper mantle, low mantle, core-mantle boundary, outer core, and inner core. The results provide a new window on the investigation of the mineral properties at Earth's conditions.

  3. Characterizing Extreme Ionospheric Storms

    NASA Astrophysics Data System (ADS)

    Sparks, L.; Komjathy, A.; Altshuler, E.

    2011-12-01

    Ionospheric storms consist of disturbances of the upper atmosphere that generate regions of enhanced electron density typically lasting several hours. Depending upon the storm magnitude, gradients in electron density can sometimes become large and highly localized. The existence of such localized, dense irregularities is a major source of positioning error for users of the Global Positioning System (GPS). Consequently, satellite-based augmentation systems have been implemented to improve the accuracy and to ensure the integrity of user position estimates derived from GPS measurements. Large-scale irregularities generally do not pose a serious threat to estimate integrity as they can be readily detected by such systems. Of greater concern, however, are highly localized irregularities that interfere with the propagation of a signal detected by a user measurement but are poorly sampled by the receivers in the system network. The most challenging conditions have been found to arise following disturbances of large magnitude that occur only rarely over the course of a solar cycle. These extremely disturbed conditions exhibit behavior distinct from moderately disturbed conditions and, hence, have been designated "extreme storms". In this paper we examine and compare the behavior of the extreme ionospheric storms of solar cycle 23 (or, more precisely, extreme storms occurring between January 1, 2000, and December 31, 2008), as represented in maps of vertical total electron content. To identify these storms, we present a robust means of quantifying the regional magnitude of an ionospheric storm. Ionospheric storms are observed frequently to occur in conjunction with magnetic storms, i.e., periods of geophysical activity as measured by magnetometers. While various geomagnetic indices, such as the disturbance storm time (Dst) and the planetary Kp index, have long been used to rank the magnitudes of distinct magnetic storms, no comparable, generally recognized index exists for

  4. Metagenomics of extreme environments.

    PubMed

    Cowan, D A; Ramond, J-B; Makhalanyane, T P; De Maayer, P

    2015-06-01

    Whether they are exposed to extremes of heat or cold, or buried deep beneath the Earth's surface, microorganisms have an uncanny ability to survive under these conditions. This ability to survive has fascinated scientists for nearly a century, but the recent development of metagenomics and 'omics' tools has allowed us to make huge leaps in understanding the remarkable complexity and versatility of extremophile communities. Here, in the context of the recently developed metagenomic tools, we discuss recent research on the community composition, adaptive strategies and biological functions of extremophiles.

  5. Acute extremity compartment syndrome.

    PubMed

    Tumbarello, C

    2000-01-01

    Acute Extremity Compartment Syndrome is a disorder, which can cause loss of limb if left untreated. Compartment syndrome develops when pressures within the fascial compartments become elevated, resulting in decreased perfusion to muscles and nerves. Left untreated, tissue death occurs. Rapid identification of clinical signs can decrease severity of symptoms. Diligent nursing assessment and monitoring of clinical signs, with communication to the physician, will facilitate rapid treatment by the physician. The primary treatment option is early identification and intervention through performance of a fasciotomy.

  6. Extremely Isolated Elliptical Galaxies

    NASA Astrophysics Data System (ADS)

    Fuse, Christopher R.; Marcum, P.; Fanelli, M.; Aars, C.

    2006-06-01

    Isolated galaxies provide a means of assessing the evolution of galactic systems. Extremely isolated galaxies define a zero-interaction baseline for comparative studies of galaxy evolution. We present results of a search for isolated elliptical galaxies (IEGs). We utilize the optical imaging data produced by the Sloan Digital Sky Survey (SDSS) to identify candidate galaxies from Release 1-4 of the SDSS. Candidate IEGs meet strict isolation criteria: Any IEG must be separated by at least 2.5 Mpc from any neighboring non-dwarf galaxy having a MV fainter than -16.5 mag. The candidate isolated systems have no non-dwarf neighbors within a distance such that we can insure that the IEGs have never interacted with another existing galaxy since formation.In order to increase the signal-to-noise ratio, we have used the SDSS images in the u,g,r filters to create combined sets of images for each IEG. The stacked images permit a more robust determination of the morphology of the candidate galaxies. Verification that these are spheroidal systems is achieved through a bulge/disk decomposition technique using standard surface photometry. Our preliminary sample of 51 isolated systems defines a complete volume-limited population of extremely isolated early-type galaxies within a distance of 72Mpc

  7. Solar extreme events

    NASA Astrophysics Data System (ADS)

    Hudson, Hugh S.

    2015-08-01

    Solar flares and CMEs have a broad range of magnitudes. This review discusses the possibility of “extreme events,” defined as those with magnitudes greater than have been seen in the existing historical record. For most quantitative measures, this direct information does not extend more than a century and a half into the recent past. The magnitude distributions (occurrence frequencies) of solar events (flares/CMEs) typically decrease with the parameter measured or inferred (peak flux, mass, energy etc. Flare radiation fluxes tend to follow a power law slightly flatter than S-2, where S represents a peak flux; solar particle events (SPEs) follow a still flatter power law up to a limiting magnitude, and then appear to roll over to a steeper distribution, which may take an exponential form or follow a broken power law. This inference comes from the terrestrial 14C record and from the depth dependence of various radioisotope proxies in the lunar regolith and in meteorites. Recently major new observational results have impacted our use of the relatively limited historical record in new ways: the detection of actual events in the 14C tree-ring records, and the systematic observations of flares and “superflares” by the Kepler spacecraft. I discuss how these new findings may affect our understanding of the distribution function expected for extreme solar events.

  8. "Extreme Programming" in a Bioinformatics Class

    ERIC Educational Resources Information Center

    Kelley, Scott; Alger, Christianna; Deutschman, Douglas

    2009-01-01

    The importance of Bioinformatics tools and methodology in modern biological research underscores the need for robust and effective courses at the college level. This paper describes such a course designed on the principles of cooperative learning based on a computer software industry production model called "Extreme Programming" (EP). The…

  9. Temperature Extremes, Health, and Human Capital

    ERIC Educational Resources Information Center

    Zivin, Joshua Graff; Shrader, Jeffrey

    2016-01-01

    The extreme temperatures expected under climate change may be especially harmful to children. Children are more vulnerable to heat partly because of their physiological features, but, perhaps more important, because they behave and respond differently than adults do. Children are less likely to manage their own heat risk and may have fewer ways to…

  10. Some characterizations of unique extremality

    NASA Astrophysics Data System (ADS)

    Yao, Guowu

    2008-07-01

    In this paper, it is shown that some necessary characteristic conditions for unique extremality obtained by Zhu and Chen are also sufficient and some sufficient ones by them actually imply that the uniquely extremal Beltrami differentials have a constant modulus. In addition, some local properties of uniquely extremal Beltrami differentials are given.

  11. Monster symmetry and extremal CFTs

    NASA Astrophysics Data System (ADS)

    Gaiotto, Davide

    2012-11-01

    We test some recent conjectures about extremal selfdual CFTs, which are the candidate holographic duals of pure gravity in AdS 3. We prove that no c = 48 extremal selfdual CFT or SCFT may possess Monster symmetry. Furthermore, we disprove a recent argument against the existence of extremal selfdual CFTs of large central charge.

  12. Identification of victims in extreme events

    NASA Astrophysics Data System (ADS)

    Talipova, Yu.; Polukhina, O.

    2009-04-01

    Catastrophic natural disasters including tsunami events are increased the frequency in last years. One of very important problems here is the identification of personality of the victims. Due to difficult identification of the dead bodies lied into water for a long time the analysis of tooth-jaw system is proposed to apply because teeth are extremely stable to the destructive actions of environment. The method of identification of the age, sex and race of victims based on the mathematic model of pattern recognition and collected database is described. Some examples from extreme sea wave events are analyzed.

  13. Extremophiles and extreme environments.

    PubMed

    Rampelotto, Pabulo Henrique

    2013-08-07

    Over the last decades, the study of extremophiles has providing ground breaking discoveries that challenge the paradigms of modern biology and make us rethink intriguing questions such as "what is life?", "what are the limits of life?", and "what are the fundamental features of life?". These findings and possibilities have made the study of life in extreme environments one of the most exciting areas of research in recent decades. However, despite the latest advances we are just in the beginning of exploring and characterizing the world of extremophiles. This special issue discusses several aspects of these fascinating organisms, exploring their habitats, biodiversity, ecology, evolution, genetics, biochemistry, and biotechnological applications in a collection of exciting reviews and original articles written by leading experts and research groups in the field. [...].

  14. Pulsars and Extreme Physics

    NASA Astrophysics Data System (ADS)

    Bell-Burnell, Jocelyn

    2004-10-01

    Pulsars were discovered 35 years ago. What do we know about them now, and what have they taught us about the extremes of physics? With an average density comparable to that of the nucleus, magnetic fields around 108 T and speeds close to c these objects have stretched our understanding of the behaviour of matter. They serve as extrememly accurate clocks with which to carry out precision experiments in relativity. Created in cataclysmic explosions, pulsars are a (stellar) form of life after death. After half a billion revolutions most pulsars finally die, but amazingly some are born again to yet another, even weirder, afterlife. Pulsar research continues lively, delivering exciting, startling and almost unbelievable results!

  15. Investigating NARCCAP Precipitation Extremes via Bivariate Extreme Value Theory (Invited)

    NASA Astrophysics Data System (ADS)

    Weller, G. B.; Cooley, D. S.; Sain, S. R.; Bukovsky, M. S.; Mearns, L. O.

    2013-12-01

    We introduce methodology from statistical extreme value theory to examine the ability of reanalysis-drive regional climate models to simulate past daily precipitation extremes. Going beyond a comparison of summary statistics such as 20-year return values, we study whether the most extreme precipitation events produced by climate model simulations exhibit correspondence to the most extreme events seen in observational records. The extent of this correspondence is formulated via the statistical concept of tail dependence. We examine several case studies of extreme precipitation events simulated by the six models of the North American Regional Climate Change Assessment Program (NARCCAP) driven by NCEP reanalysis. It is found that the NARCCAP models generally reproduce daily winter precipitation extremes along the Pacific coast quite well; in contrast, simulation of past daily summer precipitation extremes in a central US region is poor. Some differences in the strength of extremal correspondence are seen in the central region between models which employ spectral nudging and those which do not. We demonstrate how these techniques may be used to draw a link between extreme precipitation events and large-scale atmospheric drivers, as well as to downscale extreme precipitation simulated by a future run of a regional climate model. Specifically, we examine potential future changes in the nature of extreme precipitation along the Pacific coast produced by the pineapple express (PE) phenomenon. A link between extreme precipitation events and a "PE Index" derived from North Pacific sea-surface pressure fields is found. This link is used to study PE-influenced extreme precipitation produced by a future-scenario climate model run.

  16. Statistical analysis of extreme auroral electrojet indices

    NASA Astrophysics Data System (ADS)

    Nakamura, Masao; Yoneda, Asato; Oda, Mitsunobu; Tsubouchi, Ken

    2015-09-01

    Extreme auroral electrojet activities can damage electrical power grids due to large induced currents in the Earth, degrade radio communications and navigation systems due to the ionospheric disturbances and cause polar-orbiting satellite anomalies due to the enhanced auroral electron precipitation. Statistical estimation of extreme auroral electrojet activities is an important factor in space weather research. For this estimation, we utilize extreme value theory (EVT), which focuses on the statistical behavior in the tail of a distribution. As a measure of auroral electrojet activities, auroral electrojet indices AL, AU, and AE, are used, which describe the maximum current strength of the westward and eastward auroral electrojets and the sum of the two oppositely directed in the auroral latitude ionosphere, respectively. We provide statistical evidence for finite upper limits to AL and AU and estimate the annual expected number and probable intensity of their extreme events. We detect two different types of extreme AE events; therefore, application of the appropriate EVT analysis to AE is difficult.

  17. Biological Extreme Events: A Research Framework

    NASA Astrophysics Data System (ADS)

    Gutschick, Vincent P.; BassiriRad, Hormoz

    2010-03-01

    Efforts designed to understand and predict adaptation responses of organisms and populations to global climate change must make a clear distinction between responses to changes in average conditions (e.g., doubling of atmospheric carbon dioxide concentration accompanied by an average increase of 1°-3°C in global air temperature by the end of this century) and responses resulting from increased incidence of extreme events [Loehle and LeBlanc, 1996; Easterling et al., 2000; Garrett et al., 2006]. Such distinction is critical because, unlike changes in average conditions, extremes (e.g., megadroughts, fire, flooding, hurricanes, heat waves, and pest outbreaks) are typically short in duration but challenge organisms and populations considerably further beyond their ability to acclimate than those expected from average trends in climate changes. There is growing evidence that climatic extremes have been rising in frequency or magnitude during the last part of the twentieth century and will continue to increase during the remainder of this century [Easterling et al., 2000; Meehl et al., 2000; Parmesan and Yohe, 2003; Barnett et al., 2006]. More important, the frequency of extremes is likely to increase even if the climatic means do not change substantially [Intergovernmental Panel on Climate Change (IPCC), 2001, chapter 10]. Therefore, it makes sense to pay special attention to extremes as major agents of biological adaption (genetic change) when considering global climate change.

  18. Modeling, Forecasting and Mitigating Extreme Earthquakes

    NASA Astrophysics Data System (ADS)

    Ismail-Zadeh, A.; Le Mouel, J.; Soloviev, A.

    2012-12-01

    Recent earthquake disasters highlighted the importance of multi- and trans-disciplinary studies of earthquake risk. A major component of earthquake disaster risk analysis is hazards research, which should cover not only a traditional assessment of ground shaking, but also studies of geodetic, paleoseismic, geomagnetic, hydrological, deep drilling and other geophysical and geological observations together with comprehensive modeling of earthquakes and forecasting extreme events. Extreme earthquakes (large magnitude and rare events) are manifestations of complex behavior of the lithosphere structured as a hierarchical system of blocks of different sizes. Understanding of physics and dynamics of the extreme events comes from observations, measurements and modeling. A quantitative approach to simulate earthquakes in models of fault dynamics will be presented. The models reproduce basic features of the observed seismicity (e.g., the frequency-magnitude relationship, clustering of earthquakes, occurrence of extreme seismic events). They provide a link between geodynamic processes and seismicity, allow studying extreme events, influence of fault network properties on seismic patterns and seismic cycles, and assist, in a broader sense, in earthquake forecast modeling. Some aspects of predictability of large earthquakes (how well can large earthquakes be predicted today?) will be also discussed along with possibilities in mitigation of earthquake disasters (e.g., on 'inverse' forensic investigations of earthquake disasters).

  19. Women in extreme poverty.

    PubMed

    1994-01-01

    Population is estimated to increase from 5.5 billion in 1990 to 10 billion by 2050; the poverty level is expected to increase from 1 billion to 2-3 billion people. Women in development has been promoted throughout the UN and development system, but women in poverty who perform work in the informal sector are still uncounted, and solutions are elusive. The issue of extreme poverty can not be approached as just another natural disaster with immediate emergency relief. Many people live in precarious economic circumstances throughout their lives. Recent research reveals a greater understanding of the underlying causes and the need for inclusion of poor women in sustainable development. Sanitation, water, housing, health facilities need to be improved. Women must have access to education, opportunities for trading, and loans on reasonable terms. UNESCO makes available a book on survival strategies for poor women in the informal sector. The profile shows common problems of illiteracy, broken marriages, and full time involvement in provision of subsistence level existence. Existence is a fragile balance. Jeanne Vickers' "Women and the World" offers simple, low cost interventions for aiding extremely poor women. The 1992 Commission on the Status of Women was held in Vienna. Excerpts from several speeches are provided. The emphasis is on some global responses and an analysis of solutions. The recommendation is for attention to the gender dimension of poverty. Women's dual role contributes to greater disadvantages. Women are affected differently by macroeconomic factors, and that there is intergenerational transfer of poverty. Social services should be viewed as investments and directed to easing the burdens on time and energy. Public programs must be equipped to deal with poverty and to bring about social and economic change. Programs must be aware of the different distribution of resources within households. Women must be recognized as principal economic providers within

  20. Extreme ultraviolet lithography machine

    SciTech Connect

    Tichenor, D.A.; Kubiak, G.D.; Haney, S.J.; Sweeney, D.W.

    2000-02-29

    An extreme ultraviolet lithography (EUVL) machine or system is disclosed for producing integrated circuit (IC) components, such as transistors, formed on a substrate. The EUVL machine utilizes a laser plasma point source directed via an optical arrangement onto a mask or reticle which is reflected by a multiple mirror system onto the substrate or target. The EUVL machine operates in the 10--14 nm wavelength soft x-ray photon. Basically the EUV machine includes an evacuated source chamber, an evacuated main or project chamber interconnected by a transport tube arrangement, wherein a laser beam is directed into a plasma generator which produces an illumination beam which is directed by optics from the source chamber through the connecting tube, into the projection chamber, and onto the reticle or mask, from which a patterned beam is reflected by optics in a projection optics (PO) box mounted in the main or projection chamber onto the substrate. In one embodiment of a EUVL machine, nine optical components are utilized, with four of the optical components located in the PO box. The main or projection chamber includes vibration isolators for the PO box and a vibration isolator mounting for the substrate, with the main or projection chamber being mounted on a support structure and being isolated.

  1. Extreme ultraviolet lithography machine

    DOEpatents

    Tichenor, Daniel A.; Kubiak, Glenn D.; Haney, Steven J.; Sweeney, Donald W.

    2000-01-01

    An extreme ultraviolet lithography (EUVL) machine or system for producing integrated circuit (IC) components, such as transistors, formed on a substrate. The EUVL machine utilizes a laser plasma point source directed via an optical arrangement onto a mask or reticle which is reflected by a multiple mirror system onto the substrate or target. The EUVL machine operates in the 10-14 nm wavelength soft x-ray photon. Basically the EUV machine includes an evacuated source chamber, an evacuated main or project chamber interconnected by a transport tube arrangement, wherein a laser beam is directed into a plasma generator which produces an illumination beam which is directed by optics from the source chamber through the connecting tube, into the projection chamber, and onto the reticle or mask, from which a patterned beam is reflected by optics in a projection optics (PO) box mounted in the main or projection chamber onto the substrate. In one embodiment of a EUVL machine, nine optical components are utilized, with four of the optical components located in the PO box. The main or projection chamber includes vibration isolators for the PO box and a vibration isolator mounting for the substrate, with the main or projection chamber being mounted on a support structure and being isolated.

  2. Detectors in Extreme Conditions

    SciTech Connect

    Blaj, G.; Carini, G.; Carron, S.; Haller, G.; Hart, P.; Hasi, J.; Herrmann, S.; Kenney, C.; Segal, J.; Tomada, A.

    2015-08-06

    Free Electron Lasers opened a new window on imaging the motion of atoms and molecules. At SLAC, FEL experiments are performed at LCLS using 120Hz pulses with 1012 - 1013 photons in 10 femtoseconds (billions of times brighter than the most powerful synchrotrons). This extreme detection environment raises unique challenges, from obvious to surprising. Radiation damage is a constant threat due to accidental exposure to insufficiently attenuated beam, focused beam and formation of ice crystals reflecting the beam onto the detector. Often high power optical lasers are also used (e.g., 25TW), increasing the risk of damage or impeding data acquisition through electromagnetic pulses (EMP). The sample can contaminate the detector surface or even produce shrapnel damage. Some experiments require ultra high vacuum (UHV) with strict design, surface contamination and cooling requirements - also for detectors. The setup is often changed between or during experiments with short turnaround times, risking mechanical and ESD damage, requiring work planning, training of operators and sometimes continuous participation of the LCLS Detector Group in the experiments. The detectors used most often at LCLS are CSPAD cameras for hard x-rays and pnCCDs for soft x-rays.

  3. Understanding water extremes with caution

    NASA Astrophysics Data System (ADS)

    Stehlík, Milan; Stehlíková, Silvia; Torres, Sebastián

    2016-06-01

    We discuss a sensitive topic, how to scientifically estimate extremes in water quality managements. Such extremes are incorporating establishment of thresholds or levels of certain chemicals in the drinking water. In particular, we address the water fluoridation and quality of drinking water in Chile. Statistical approaches demonstrating the necessary background of water manager will be given in a survey exposition to establish link between statistics of extremes and practice.

  4. Extreme wind climate in the Czech Republic

    NASA Astrophysics Data System (ADS)

    Pop, L.; Hanslian, D.; Jiri, H.

    2011-12-01

    -convective extreme wind events is roughly at the same order. The convective events usually occur from April to August, whereas the non-convective events are typical for cold months from October to March. In mountainous regions, the non-convective events are most important, however, the impact of convective storms is high in lowlands, partially because of the seasonal foliage. The convective events are usually connected with squall lines or frontal waves. The non-convective events are mostly caused by strong southwest to northwest flow; a smaller specific group of these events, typical for some regions, is connected with south to southeast flow.

  5. Detection and attribution of extreme weather disasters

    NASA Astrophysics Data System (ADS)

    Huggel, Christian; Stone, Dáithí; Hansen, Gerrit

    2014-05-01

    Single disasters related to extreme weather events have caused loss and damage on the order of up to tens of billions US dollars over the past years. Recent disasters fueled the debate about whether and to what extent these events are related to climate change. In international climate negotiations disaster loss and damage is now high on the agenda, and related policy mechanisms have been discussed or are being implemented. In view of funding allocation and effective risk reduction strategies detection and attribution to climate change of extreme weather events and disasters is a key issue. Different avenues have so far been taken to address detection and attribution in this context. Physical climate sciences have developed approaches, among others, where variables that are reasonably sampled over climatically relevant time periods and related to the meteorological characteristics of the extreme event are examined. Trends in these variables (e.g. air or sea surface temperatures) are compared between observations and climate simulations with and without anthropogenic forcing. Generally, progress has been made in recent years in attribution of changes in the chance of some single extreme weather events to anthropogenic climate change but there remain important challenges. A different line of research is primarily concerned with losses related to the extreme weather events over time, using disaster databases. A growing consensus is that the increase in asset values and in exposure are main drivers of the strong increase of economic losses over the past several decades, and only a limited number of studies have found trends consistent with expectations from climate change. Here we propose a better integration of existing lines of research in detection and attribution of extreme weather events and disasters by applying a risk framework. Risk is thereby defined as a function of the probability of occurrence of an extreme weather event, and the associated consequences

  6. Extreme Environments: Why NASA?

    NASA Astrophysics Data System (ADS)

    Meyer, M. A.

    2002-12-01

    Life on our planet is the only known example in the universe and so we are relegated to this planet for the study of life. However, life may be a natural consequence of planet formation, and so the study of the origin, evolution, distribution and future of life may be greatly informed by planetary exploration. Astrobiology has adopted several approaches to study life on Earth, for deducing our origins, for determining the likelihood of life elsewhere, and for enabling the search for evidence of past or present life. The first approach has been the Exobiology Program, centered around understanding the origins of life and which supports individual investigator research. Second has been the construction of consortia-type research in which researchers from different disciplines focus on a larger problem. This structure began with NASA Specialized Centers of Research and Training and has grown to include the Astrobiology Institute - a collection of competitively selected groups of researchers attacking problems in Astrobiology as individual teams and as a consolidated Institute. With the formation of an intellectual basis for exploring for life elsewhere, Astrobiology has initiated the competitive research and development program in instrument development (Astrobiology Science and Technology for Instrument Development [ASTID] Program) that would enable future mission instruments for the exploration of planetary bodies in the search for prebiotic chemistry, habitable environments (past or present), biomarkers, and possibly life itself. However, the act of exploring requires robust instrumentation, mobile robotic platforms, efficient operations, and a high level of autonomy. To this end, Astrobiology has started a new research activity that promotes scientifically-driven robotic exploration of extreme environments on Earth that are analogous to suspected habitable environments on other planetary bodies. The program is called Astrobiology Science and Technology for

  7. Precipitation extremes with climate variability and change

    NASA Astrophysics Data System (ADS)

    Ganguly, A. R.

    2011-12-01

    Significant gaps exist in our understanding of hydro-meteorological processes in the context of climate variability or change. However, despite the uncertainties, developing relatively credible insights for precipitation extremes at scales relevant for hydrology is necessary and may be possible. Statistical analyses of observed and model-simulated precipitation data, particularly methods based on extreme value theory, have demonstrated the potential to yield new insights. Specifically, a delineation of the impacts of global climate change versus regional changes in land use or urbanization may be possible and could be important for policy-makers. Precipitation extremes have known dependence on variables like sea surface temperatures, atmospheric temperature profiles and wind velocities, some of which may be better predicted than precipitation from models, exhibit less variability in observations and may not be as subject to thresholds and intermittences in either models or observations. Thus, leveraging the information content in these auxiliary variables through data mining or network science based approaches, especially if the techniques are informed by process understanding at multiple scales, may help improve regional projections of precipitation and corresponding extremes. Enhanced regional projections of precipitation and their extremes can help drive models of hydrology and hence better inform water managers, especially at scales that matter for water resources planning or managing hydraulic infrastructures. A combination of physics-based models, data-guided mathematical approaches, and quantitative techniques informed by conceptual process understanding, may be a way forward to understand the possible consequences of climate variability and global or regional change on precipitation extremes. Examples and case studies are presented from the published literature and from ongoing research.

  8. Extreme Rainfall Events Over Southern Africa: Assessment of a Climate Model to Reproduce Daily Extremes

    NASA Astrophysics Data System (ADS)

    Williams, C.; Kniveton, D.; Layberry, R.

    2007-12-01

    It is increasingly accepted that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The subcontinent is considered especially vulnerable extreme events, due to a number of factors including extensive poverty, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of a state-of-the-art climate model to simulate climate at daily timescales is carried out using satellite derived rainfall data from the Microwave Infra-Red Algorithm (MIRA). This dataset covers the period from 1993-2002 and the whole of southern Africa at a spatial resolution of 0.1 degree longitude/latitude. Once the model's ability to reproduce extremes has been assessed, idealised regions of SST anomalies are used to force the model, with the overall aim of investigating the ways in which SST anomalies influence rainfall extremes over southern Africa. In this paper, results from sensitivity testing of the UK Meteorological Office Hadley Centre's climate model's domain size are firstly presented. Then simulations of current climate from the model, operating in both regional and global mode, are compared to the MIRA dataset at daily timescales. Thirdly, the ability of the model to reproduce daily rainfall extremes will be assessed, again by a comparison with extremes from the MIRA dataset. Finally, the results from the idealised SST experiments are briefly presented, suggesting associations between rainfall extremes and both local and remote SST anomalies.

  9. Gender, Education, Extremism and Security

    ERIC Educational Resources Information Center

    Davies, Lynn

    2008-01-01

    This paper examines the complex relationships between gender, education, extremism and security. After defining extremism and fundamentalism, it looks first at the relationship of gender to violence generally, before looking specifically at how this plays out in more extremist violence and terrorism. Religious fundamentalism is also shown to have…

  10. Denitrification by extremely halophilic bacteria

    NASA Technical Reports Server (NTRS)

    Hochstein, L. I.; Tomlinson, G. A.

    1985-01-01

    Extremely halophilic bacteria were isolated from widely separated sites by anaerobic enrichment in the presence of nitrate. The anaerobic growth of several of these isolates was accompanied by the production of nitrite, nitrous oxide, and dinitrogen. These results are a direct confirmation of the existence of extremely halophilic denitrifying bacteria, and suggest that such bacteria may be common inhabitants of hypersaline environments.

  11. Representing Extremes in Agricultural Models

    NASA Technical Reports Server (NTRS)

    Ruane, Alex

    2015-01-01

    AgMIP and related projects are conducting several activities to understand and improve crop model response to extreme events. This involves crop model studies as well as the generation of climate datasets and scenarios more capable of capturing extremes. Models are typically less responsive to extreme events than we observe, and miss several forms of extreme events. Models also can capture interactive effects between climate change and climate extremes. Additional work is needed to understand response of markets and economic systems to food shocks. AgMIP is planning a Coordinated Global and Regional Assessment of Climate Change Impacts on Agricultural Production and Food Security with an aim to inform the IPCC Sixth Assessment Report.

  12. Extreme events in computational turbulence.

    PubMed

    Yeung, P K; Zhai, X M; Sreenivasan, Katepalli R

    2015-10-13

    We have performed direct numerical simulations of homogeneous and isotropic turbulence in a periodic box with 8,192(3) grid points. These are the largest simulations performed, to date, aimed at improving our understanding of turbulence small-scale structure. We present some basic statistical results and focus on "extreme" events (whose magnitudes are several tens of thousands the mean value). The structure of these extreme events is quite different from that of moderately large events (of the order of 10 times the mean value). In particular, intense vorticity occurs primarily in the form of tubes for moderately large events whereas it is much more "chunky" for extreme events (though probably overlaid on the traditional vortex tubes). We track the temporal evolution of extreme events and find that they are generally short-lived. Extreme magnitudes of energy dissipation rate and enstrophy occur simultaneously in space and remain nearly colocated during their evolution. PMID:26424452

  13. Extreme Mean and Its Applications

    NASA Technical Reports Server (NTRS)

    Swaroop, R.; Brownlow, J. D.

    1979-01-01

    Extreme value statistics obtained from normally distributed data are considered. An extreme mean is defined as the mean of p-th probability truncated normal distribution. An unbiased estimate of this extreme mean and its large sample distribution are derived. The distribution of this estimate even for very large samples is found to be nonnormal. Further, as the sample size increases, the variance of the unbiased estimate converges to the Cramer-Rao lower bound. The computer program used to obtain the density and distribution functions of the standardized unbiased estimate, and the confidence intervals of the extreme mean for any data are included for ready application. An example is included to demonstrate the usefulness of extreme mean application.

  14. Lightcurves of Extreme Debris Disks

    NASA Astrophysics Data System (ADS)

    Rieke, George; Meng, Huan; Su, Kate

    2012-12-01

    We have recently discovered that some planetary debris disks with extreme fractional luminosities are variable on the timescale of a few years. This behavior opens a new possibility to understand planet building. Two of the known variable disks are around solar-like stars in the age range of 30 to 100+ Myr, which is the expected era of the final stages of terrestrial planet building. Such variability can be attributed to violent collisions (up to ones on the scale of the Moon-forming event between the proto-Earth and another proto-planet). The collisional cascades that are the aftermaths of these events can produce large clouds of tiny dust grains, possibly even condensed from silica vapor. A Spitzer pilot program has obtained the lightcurve of such a debris disk and caught two minor outbursts. Here we propose to continue the lightcurve monitoring with higher sampling rates and to expand it to more disks. The proposed time domain observations are a new dimension of debris disk studies that can bring unique insight to their evolution, providing important constraints on the collisional and dynamical models of terrestrial planet formation.

  15. Anders Breivik: Extreme Beliefs Mistaken for Psychosis.

    PubMed

    Rahman, Tahir; Resnick, Phillip J; Harry, Bruce

    2016-03-01

    The case of Anders Breivik, who committed mass murder in Norway in 2011, stirred controversy among forensic mental health experts. His bizarrely composed compendium and references to himself as the "Knights Templar" raised concerns that he had a psychotic mental illness. Beliefs such as Mr. Breivik's that precede odd, unusual, or extremely violent behavior present a unique challenge to the forensic evaluator, who sometimes struggles to understand those beliefs. Psychotic disorder frequently is invoked to characterize odd, unusual, or extreme beliefs, with a classification that has evolved over time. However, the important concept of overvalued idea, largely ignored in American psychiatry, may better characterize these beliefs in some cases. We discuss the definitions of delusion and overvalued ideas in the context of Anders Breivik's rigidly held extreme beliefs. We also review the British definition of overvalued idea and discuss McHugh's construct, to introduce the term "extreme overvalued belief" as an aid in sharpening the forensic evaluator's conceptualization of these and similar beliefs.

  16. Recurrent solitary fibrous tumor in distal lower extremity: An extremely rare entity.

    PubMed

    Chandanwale, Shirish S; Gore, Charusheela R; Sammi, Amit B; Shah, Komal R; Kaur, Parveen R

    2014-07-01

    Solitary fibrous tumor (SFT) represents a spectrum of mesenchymal tumors, encompassing tumors previously termed hemangiopericytoma, as having intermediate biological potential. Though they can occur at any site, lower distal extremity is a rare site and recurrence in it is extremely rare. Behavior of SFT is unpredictable. Histomorphology and clinical follow-up have poor correlation. The most important single indicator of clinical outcome is complete excision of the tumor at the time of primary presentation. Tumors with positive margins require close follow-up for several years owing to the potential for late local recurrence.

  17. Extreme Thrombocytosis and Cardiovascular Surgery

    PubMed Central

    Natelson, Ethan A.

    2012-01-01

    Extreme thrombocytosis is a major risk factor for excessive bleeding and for thrombosis, either of which can complicate cardiovascular surgical and interventional procedures. Extreme thrombocytosis can also cause an unusual syndrome, erythromelalgia, that results in a type of chronic microvascular occlusive arterial disease. We present the differential diagnosis of conditions that may lead to extreme thrombocytosis, 3 cases (each of which illustrates a different potential complication), and a review of the pertinent medical literature. Correcting excessive thrombocytosis is typically not difficult, whether electively or acutely, and effective therapy usually controls thrombosis and excessive hemorrhage postprocedurally. PMID:23304015

  18. Nonparametric Spatial Models for Extremes: Application to Extreme Temperature Data.

    PubMed

    Fuentes, Montserrat; Henry, John; Reich, Brian

    2013-03-01

    Estimating the probability of extreme temperature events is difficult because of limited records across time and the need to extrapolate the distributions of these events, as opposed to just the mean, to locations where observations are not available. Another related issue is the need to characterize the uncertainty in the estimated probability of extreme events at different locations. Although the tools for statistical modeling of univariate extremes are well-developed, extending these tools to model spatial extreme data is an active area of research. In this paper, in order to make inference about spatial extreme events, we introduce a new nonparametric model for extremes. We present a Dirichlet-based copula model that is a flexible alternative to parametric copula models such as the normal and t-copula. The proposed modelling approach is fitted using a Bayesian framework that allow us to take into account different sources of uncertainty in the data and models. We apply our methods to annual maximum temperature values in the east-south-central United States. PMID:24058280

  19. Habitability in Extreme Conditions

    NASA Astrophysics Data System (ADS)

    de Lobkowicz, Ysaline; de Crombrugghe, Guerric; Le Maire, Victor; Jago, Alban; Denies, Jonathan; van Vynckt, Delphine; Reydams, Marc; Mertens, Alexandre

    A manned space mission could be perfectly prepared in terms of sciences and technologies, but without a good habitat, a place where the needs of the crew are respected, this isolation and confinement can turn into a nightmare. There is the limitation of engineering: it is more than important to take care about architecture, when human lives are part of the experiment. The goal of the research is the analysis of the hard life of isolation and confinement in Mars' hostile environment and how architecture is a way to improve it. The objective is to place the human in the middle of the analysis. What does a person really need? Therefore Maslow's idea, the pyramid of primary needs, gives us the hierarchy to follow: first survival, food and beverage, then sleep, and only then protection, social activities and work. [1] No more luxury. If all these aspects are respected, a human is able to survive, like it did since so many years. The idea is that each of these main activities has to be related to a different type of space, to provide variability in this close environment. For example, work and relaxing areas have to be separated; a human being needs time for himself, without concentration. A workspace and a relaxing area have a different typology, different colours and lighting, dimensions, furniture. This has also to be respected in a spacecraft. For this research, different sources are used, mainly in the psychological aspect, which is the most important. [2] Therefore questionnaires, interviews, diaries of past expeditions are full of treasures. We do not have to search too far: on earth; polar expeditions, submarines, military camps, etc., give a lot of information. Some very realistic simulations, as on the Mars Desert Research Station (MDRS), will also be used as material: a good analysis of the defaults and well-organized part of the station can conduct to important conclusions. [3] A found analysis and a well-designed habitat are considerable keys for the success

  20. Spatial extremes modeling applied to extreme precipitation data in the state of Paraná

    NASA Astrophysics Data System (ADS)

    Olinda, R. A.; Blanchet, J.; dos Santos, C. A. C.; Ozaki, V. A.; Ribeiro, P. J., Jr.

    2014-11-01

    Most of the mathematical models developed for rare events are based on probabilistic models for extremes. Although the tools for statistical modeling of univariate and multivariate extremes are well developed, the extension of these tools to model spatial extremes includes an area of very active research nowadays. A natural approach to such a modeling is the theory of extreme spatial and the max-stable process, characterized by the extension of infinite dimensions of multivariate extreme value theory, and making it possible then to incorporate the existing correlation functions in geostatistics and therefore verify the extremal dependence by means of the extreme coefficient and the Madogram. This work describes the application of such processes in modeling the spatial maximum dependence of maximum monthly rainfall from the state of Paraná, based on historical series observed in weather stations. The proposed models consider the Euclidean space and a transformation referred to as space weather, which may explain the presence of directional effects resulting from synoptic weather patterns. This method is based on the theorem proposed for de Haan and on the models of Smith and Schlather. The isotropic and anisotropic behavior of these models is also verified via Monte Carlo simulation. Estimates are made through pairwise likelihood maximum and the models are compared using the Takeuchi Information Criterion. By modeling the dependence of spatial maxima, applied to maximum monthly rainfall data from the state of Paraná, it was possible to identify directional effects resulting from meteorological phenomena, which, in turn, are important for proper management of risks and environmental disasters in countries with its economy heavily dependent on agribusiness.

  1. Precipitable water extremes from ground-based GPS measurements and relationship with precipitation extremes over U.S.A

    NASA Astrophysics Data System (ADS)

    Wang, J.

    2010-12-01

    It becomes more and more important to study extreme weather and climate events because of their huge economical and societal impacts. There is also increasing concern on changes of extreme events in frequency and intensity as a result of human influences on climate. Heavy precipitation events are among many types of extreme events and have been studied extensively. Previous studies found statistically significant increases in heavy precipitation and its contribution to total annual precipitation over USA. Given the fact that the moisture supply is one of deciding factors for the precipitation intensity, it is important to document and understand the extremes of atmospheric precipitable water (PW, column-integrated water vapor amount) and their relationship with precipitation extremes. The data are required at daily (or shorter) time scales for the study of extreme events. In this study we use 30-min PW data derived from ground based GPS measurements and hourly precipitation data over the contiguous USA. We found 53 stations where the GPS and rain-gauge stations are within a 50-km distance and 50-m elevation of each other, and the data are available from 2002 to 2009. The main goal of this study is to answer the following four questions. First, how often do PW extremes in warm season (June, July and August) occur? The PW extreme is defined as values exceeding 95th percentile. Second, how many of them result in precipitation extremes? Third, what is the relationship between PW and precipitation extremes, i.e., temporal evolution and intensity correlation? Fourth, is it possible to predict precipitation extremes from PW ones?

  2. Hall sensors for extreme temperatures.

    PubMed

    Jankowski, Jakub; El-Ahmar, Semir; Oszwaldowski, Maciej

    2011-01-01

    We report on the preparation of the first complete extreme temperature Hall sensor. This means that the extreme-temperature magnetic sensitive semiconductor structure is built-in an extreme-temperature package especially designed for that purpose. The working temperature range of the sensor extends from -270 °C to +300 °C. The extreme-temperature Hall-sensor active element is a heavily n-doped InSb layer epitaxially grown on GaAs. The magnetic sensitivity of the sensor is ca. 100 mV/T and its temperature coefficient is less than 0.04 %/K. This sensor may find applications in the car, aircraft, spacecraft, military and oil and gas industries.

  3. Muscles of the Lower Extremity

    MedlinePlus

    ... Home » Cancer Registration & Surveillance Modules » Anatomy & Physiology » Muscular System » Muscle Groups » Lower Extremity Cancer Registration & Surveillance Modules Anatomy & Physiology Intro to the Human Body Body Functions & Life Process Anatomical Terminology Review Quiz ...

  4. Extreme events in computational turbulence

    PubMed Central

    Yeung, P. K.; Zhai, X. M.; Sreenivasan, Katepalli R.

    2015-01-01

    We have performed direct numerical simulations of homogeneous and isotropic turbulence in a periodic box with 8,1923 grid points. These are the largest simulations performed, to date, aimed at improving our understanding of turbulence small-scale structure. We present some basic statistical results and focus on “extreme” events (whose magnitudes are several tens of thousands the mean value). The structure of these extreme events is quite different from that of moderately large events (of the order of 10 times the mean value). In particular, intense vorticity occurs primarily in the form of tubes for moderately large events whereas it is much more “chunky” for extreme events (though probably overlaid on the traditional vortex tubes). We track the temporal evolution of extreme events and find that they are generally short-lived. Extreme magnitudes of energy dissipation rate and enstrophy occur simultaneously in space and remain nearly colocated during their evolution. PMID:26424452

  5. Degloving injuries of the extremities and torso.

    PubMed

    Kudsk, K A; Sheldon, G F; Walton, R L

    1981-10-01

    Degloving injuries of the extremities and torso occur with relative frequency and are associated with a high morbidity and mortality. The common aim of all surgical approaches is to reestablish skin coverage over the injured area, but therapies differ in both technique and results. This survey evaluates the management and results of 21 patients sustaining degloving injury of at least 2/3 the circumference of the torso or an extremity. Initial surgical techniques which employ application of the skin as a full- or split-thickness graft were contrasted with those in which salvage of the entire flap with its subcutaneous tissue was attempted. The results suggest that immediate use of the degloved skin as a full-or split-thickness skin graft gives the most satisfactory coverage to the denuded areas. Other important features in management include frequent observation and immobilization of the extremity postoperatively, and use of mesh grafts when necessary to cover large areas. Recent emphasis on the blood supply of the skin underscores the importance of its circulation as the determinant of flap survival. Daily observation until the flap becomes fixed is mandatory. Primary reattachment of the full-or split-thickness flap by suture or use of compression dressings without grafting is unsuccessful and should be abandoned as an acceptable approach to this problem.

  6. Extremal surfaces and entanglement entropy

    NASA Astrophysics Data System (ADS)

    Pal, Shesansu Sekhar

    2014-05-01

    We have obtained the equation of the extremal hypersurface by considering the Jacobson-Myers functional and computed the entanglement entropy. In this context, we show that the higher derivative corrected extremal surfaces cannot penetrate the horizon. Also, we have studied the entanglement temperature and entanglement entropy for low excited states for such higher derivative theories when the entangling region is of the strip type.

  7. Evaluation of dynamically downscaled extreme temperature using a spatially-aggregated generalized extreme value (GEV) model

    NASA Astrophysics Data System (ADS)

    Wang, Jiali; Han, Yuefeng; Stein, Michael L.; Kotamarthi, Veerabhadra R.; Huang, Whitney K.

    2016-02-01

    The weather research and forecast (WRF) model downscaling skill in extreme maximum daily temperature is evaluated by using the generalized extreme value (GEV) distribution. While the GEV distribution has been used extensively in climatology and meteorology for estimating probabilities of extreme events, accurately estimating GEV parameters based on data from a single pixel can be difficult, even with fairly long data records. This work proposes a simple method assuming that the shape parameter, the most difficult of the three parameters to estimate, does not vary over a relatively large region. This approach is applied to evaluate 31-year WRF-downscaled extreme maximum temperature through comparison with North American regional reanalysis (NARR) data. Uncertainty in GEV parameter estimates and the statistical significance in the differences of estimates between WRF and NARR are accounted for by conducting a novel bootstrap procedure that makes no assumption of temporal or spatial independence within a year, which is especially important for climate data. Despite certain biases over parts of the United States, overall, WRF shows good agreement with NARR in the spatial pattern and magnitudes of GEV parameter estimates. Both WRF and NARR show a significant increase in extreme maximum temperature over the southern Great Plains and southeastern United States in January and over the western United States in July. The GEV model shows clear benefits from the regionally constant shape parameter assumption, for example, leading to estimates of the location and scale parameters of the model that show coherent spatial patterns.

  8. Extreme Energy in China

    SciTech Connect

    Khanna, Nina; Fridley, David; Cai, Lixue

    2013-06-01

    Over the last decade, China has focused its policies simultaneously on moderating the rapid energy demand growth that has been driven by three decades of rapid economic growth and industrialization and on increasing its energy supply. In spite of these concerted efforts, however, China continues to face growing energy supply challenges, particularly with accelerating demand for oil and natural gas, both of which are now heavily dependent on imports. On the supply side, the recent 11th and 12th Five-Year Plans have emphasized accelerating conventional and nonconventional oil and gas exploration and development through pricing reforms, pipeline infrastructure expansions and 2015 production targets for shale gas and coal seam methane. This study will analyze China’s new and nonconventional oil and gas resources base, possible development paths and outlook, and the potential role for these nonconventional resources in meeting oil and gas demand. The nonconventional resources currently being considered by China and included in this study include: shale gas, coal seam methane (coal mine methane and coal bed methane), tight gas, in-situ coal gasification, tight oil and oil shale, and gas hydrates.

  9. Atomistic material behavior at extreme pressures

    DOE PAGESBeta

    Beland, Laurent K.; Osetskiy, Yury N.; Stoller, Roger E.

    2016-08-05

    Computer simulations are routinely performed to model the response of materials to extreme environments, such as neutron (or ion) irradiation. The latter involves high-energy collisions from which a recoiling atom creates a so-called atomic displacement cascade. These cascades involve coordinated motion of atoms in the form of supersonic shockwaves. These shockwaves are characterized by local atomic pressures >15 GPa and interatomic distances <2 Å. Similar pressures and interatomic distances are observed in other extreme environment, including short-pulse laser ablation, high-impact ballistic collisions and diamond anvil cells. Displacement cascade simulations using four different force fields, with initial kinetic energies ranging frommore » 1 to 40 keV, show that there is a direct relationship between these high-pressure states and stable defect production. An important shortcoming in the modeling of interatomic interactions at these short distances, which in turn determines final defect production, is brought to light.« less

  10. Resuscitation of extremely preterm infants - controversies and current evidence

    PubMed Central

    Patel, Pooja N; Banerjee, Jayanta; Godambe, Sunit V

    2016-01-01

    Despite significant advances in perinatal medicine, the management of extremely preterm infants in the delivery room remains a challenge. There is an increasing evidence for improved outcomes regarding the resuscitation and stabilisation of extremely preterm infants but there is a lack of evidence in the periviable (gestational age 23-25 wk) preterm subgroup. Presence of an experienced team during the delivery of extremely preterm infant to improve outcome is reviewed. Adaptation from foetal to neonatal cardiorespiratory haemodynamics is dependent on establishing an optimal functional residual capacity in the extremely preterm infants, thus enabling adequate gas exchange. There is sufficient evidence for a gentle approach to stabilisation of these fragile infants in the delivery room. Evidence for antenatal steroids especially in the periviable infants, delayed cord clamping, strategies to establish optimal functional residual capacity, importance of temperature control and oxygenation in delivery room in extremely premature infants is reviewed in this article. PMID:27170925

  11. Disaster Risks Reduction for Extreme Natural Hazards

    NASA Astrophysics Data System (ADS)

    Plag, H.; Jules-Plag, S.

    2013-12-01

    . Integration of these low-probability, high-impact events in DRR requires an approach focused on resilience and antifragility, as well as the ability to cope with, and recover from failure of infrastructure and social systems. Resilience does not primarily result from the robustness of infrastructure but mainly is a function of the social capital. While it is important to understand the hazards (the contribution of geosciences), it is equally important to understand the processes that let us cope with the hazards, or lead to failure (the contribution of social sciences and engineering). For the latter, we need a joint effort of social sciences and engineering and a revised science-policy relationship. Democratizing knowledge about extreme geohazards is very important in order to inform deliberations of DRR through increased resilience and reduced fragility. The current science-society dialog is not fully capable of supporting deliberative governance. Most scientific knowledge is created independent of those who could put it to use, and a transition to co-design and co-development of knowledge involving a broad stakeholder base is necessary for DRR, particularly for extreme events. This transition may have the consequence of more responsibility and even liability for science.

  12. Linking Extreme Weather Events and Extreme ENSO States

    NASA Astrophysics Data System (ADS)

    Perlwitz, J.; Hoerling, M. P.; Xu, T.; Hoell, A.; Cheng, L.; Wolter, K.

    2015-12-01

    To what extent are the risks of extreme weather events over the contiguous US, such as heavy precipitation, heat and cold waves, conditioned by the state of tropical east Pacific SSTs? Further, do extreme magnitudes of El Niño and La Niña events exert a unique and particularly strong controlling effect on weather extremes? Here, we utilize both observations and multi-model large ensemble historical simulations to characterize the behavior of 5-day maximum precipitation distributions. We focus on relations between ENSO impacts on seasonal means and weather extremes, and explore the distinction between effects based on ENSO phase and intensity. For the cold season (November to April), overall ENSO impacts on mean precipitation are shown to be consistent with observations. This signal includes enhanced seasonal mean precipitation over the southern part of the U.S. and central Great Plains during El Niño, and enhanced seasonal mean precipitation over the Midwest during La Nina. We further demonstrate how these signals change under the influence of the most extreme ENSO events, conditions that are difficult to verify from observations owing to small sample sizes, but are modeled via large ensemble methods. The statistics of 5-day maximum precipitation, with a focus on 20-year return levels that characterizes rare but potentially damaging events, are examined. We demonstrate substantial differences in changes in the risk of extreme 5-day precipitation and the seasonal mean precipitation signal, especially in such regions as California, and the western Great Plains including the Front Range of the Rockies from Montana to New Mexico. The plausibility of such behavior is discussed via physical considerations and by examining the structural uncertainty in such outcomes across three different climate models.

  13. Extreme climatic events in a changing climate: a review

    NASA Astrophysics Data System (ADS)

    Beniston, M.

    2003-04-01

    While changes in the long-term mean state of climate will have many important consequences on numerous environmental, social, and economic sectors, the most significant impacts of climatic change are likely to come about from shifts in the intensity and frequency of extreme weather events. Indeed, insurance costs resulting from extreme weather events have been steadily increasing over the last two decades, in response to both population pressures in regions that are at risk, but also because of the frequency and severity of certain forms of extremes. Regions now safe from catastrophic wind storms, heat waves, and floods could suddenly become vulnerable. The associated damage costs would consequently be extremely high. It seems appropriate, therefore, considering the environmental, human and economic costs exerted by extreme climatic events, to address the problem of whether there may be significant shifts in extremes of wind, precipitation or temperature in a changing global climate. In order to achieve these goals, the level of current scientific understanding and the availability of computational resources now enable numerical modeling techniques to be applied to this problem area. Examples will be given of particular numerical simulations of extreme events that have affected Western Europe and the alpine region in recent years. These simulations and impacts studies will be compared to observed events and trends during the 20th century, where adequate data is available to assess the manner in which certain forms of extreme events have changed, in part as a response to the global warming observed over the last 100 years.

  14. Study of extreme nuclear shapes in extreme conditions

    SciTech Connect

    Banerjee, Sudhee Ranjan

    2014-08-14

    Studies of extreme nuclear shapes have always fascinated scientists and are being pursued quite strongly over the years. Nuclei present themselves with interesting shapes and structures at different conditions of spin, excitation and also with the number of neutrons and/or protons in them. Gamma decays from the Giant dipole Resonances in nuclei can probe directly their shapes at different extreme conditions by looking at their resonant line-shapes, e.g., Jacobi shapes and shape-transitions, super/hyper-deformation etc. Similar such studies, done for the first time, using the LAMBDA high energy gamma spectrometer developed at VECC, is discussed here.

  15. Upper-extremity thrombosis in a patient after biceps tenodesis.

    PubMed

    Offoha, Roosevelt U; Garzon-Muvdi, Juan; Streiff, Michael B; McFarland, Edward G

    2014-12-01

    Deep venous thrombosis (DVT) of the upper extremity is uncommon compared with DVT of the lower extremity. Exertional DVT has been described in some athletes, especially in the dominant arm of baseball players. It is important for health care professionals to recognize the signs and symptoms of upper-extremity DVT, which can occur after exertion or after surgery of the upper extremity. Superficial venous thrombosis is also very uncommon in the upper extremity. This article describes a case of superficial venous thrombosis that mimicked DVT in the surgical (right) arm of a recreational baseball player after suprapectoral biceps tenodesis for a painful superior labrum anterior-posterior lesion. Although the superficial venous system of the upper arm has frequent connections to the deeper basilar system, it is uncommon for superficial venous thrombosis to occur concurrently with DVT. It is important for clinicians to understand the distinction between superficial venous thrombosis and DVT in the upper extremity because the physical findings, treatment, and prognosis for these 2 entities differ in the following ways: (1) superficial venous thrombosis may be accompanied by a cord, but DVT is associated with more generalized swelling; (2) superficial venous thrombosis requires symptomatic treatment only, whereas DVT requires anticoagulation; and (3) superficial venous thrombosis typically resolves with few sequelae, whereas upper-extremity DVT increases the risk of future DVT.

  16. 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.

  17. Extremity War Injuries IX: Reducing Disability Within the Military.

    PubMed

    Andersen, Col Romney C; Schmidt, Andrew H; Fitzgerald, Capt Brian T; Tintle, Lcdr Scott M; Helgeson, Maj Melvin D; Lehman, Ltc Ronald A; Davila, Col Jeffrey N; Potter, Benjamin K; Burns, Maj Travis C; Swiontkowski, Marc F; Ficke, Col James R

    2015-08-01

    Extremity War Injury Symposium IX focused on reducing disability within the military, centering on cartilage defects, amputations, and spinal cord injury. Many areas of upper and lower extremity trauma and disability were discussed, including segmental nerve injuries, upper extremity allotransplantation, and the importance of patient-reported functional outcomes compared with the traditionally reported measures. Strategic planning addressed progression toward clinical solutions by setting clear objectives and goals and outlining pathways to address the "translation gap" that often prevents bridging of basic science to clinical application.

  18. Assessment of the extremity of heavy precipitation

    NASA Astrophysics Data System (ADS)

    Smidova, Jana; Müller, Miloslav

    2013-04-01

    Considering all natural disasters occurring on the Czech territory, heavy precipitation and associated flooding pose the greatest direct risk. To explain the causes and development of flood events, it is important to analyze the occurrence of intense precipitation in the past. A frequently used method of evaluation of heavy precipitation which is based only on rainfall intensity, total rainfall depth or duration of the events does not enable to compare precipitation events in terms of their spatiotemporal extremity. The methods presented in the paper introduce spatial and temporal dimensions in the assessment of the extremity of heavy precipitation, which allows, among other things, to specify the predominant character of precipitation. This study investigates the dependencies between temporal and spatial variability of heavy precipitation and their extremeness. Selected cases of heavy precipitation observed in the upper Elbe basin to the gauging station Němčice, Czech Republic, in the second half of the 20th century, are studied. SAD (severity-area-duration) curves and severity diagrams are developed for each precipitation event. These figures show a continuous view on the territory in which precipitation was concentrated during specific time interval. Methods in the evaluation of extremity precipitation events are based from the return period precipitation amounts measured in stations. The events are further characterized by the size of the area and rainfall duration. One-day to six-day return periods of precipitation are always confronted. Applied methods allow comparing precipitation events not only in terms of extremity (return period precipitation) but also their temporal and spatial distribution. They show that the heavy precipitation concentrated over a large area, or conversely affected only a small area. Temporal scales are taken into account in the analysis of extremity of heavy precipitation and duration time of heavy precipitation is also displayed

  19. Rainfall variability and extremes over southern Africa: assessment of a climate model to reproduce daily extremes

    NASA Astrophysics Data System (ADS)

    Williams, C.; Kniveton, D.; Layberry, R.

    2009-04-01

    It is increasingly accepted that that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The subcontinent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of ability of a state of the art climate model to simulate climate at daily timescales is carried out using satellite derived rainfall data from the Microwave Infra-Red Algorithm (MIRA). This dataset covers the period from 1993-2002 and the whole of southern Africa at a spatial resolution of 0.1 degree longitude/latitude. The ability of a climate model to simulate current climate provides some indication of how much confidence can be applied to its future predictions. In this paper, simulations of current climate from the UK Meteorological Office Hadley Centre's climate model, in both regional and global mode, are firstly compared to the MIRA dataset at daily timescales. This concentrates primarily on the ability of the model to simulate the spatial and temporal patterns of rainfall variability over southern Africa. Secondly, the ability of the model to reproduce daily rainfall extremes will

  20. Current management of the mangled upper extremity.

    PubMed

    Bumbasirevic, Marko; Stevanovic, Milan; Lesic, Aleksandar; Atkinson, Henry D E

    2012-11-01

    Mangled describes an injury caused by cutting, tearing, or crushing, which leads to the limb becoming unrecognizable; in essence, there are two treatment options for mangled upper extremities, amputation and salvage reconstruction. With advances in our understanding of human physiology and basic science, and with the development of new fixation devices, modern microsurgical techniques and the possibility of different types of bony and soft tissue reconstruction, the clinical and functional outcomes are often good, and certainly preferable to those of contemporary prosthetics. Early or even immediate (emergency) complete upper extremity reconstruction appears to give better results than delayed or late reconstruction and should be the treatment of choice where possible. Before any reconstruction is attempted, injuries to other organs must be excluded. Each step in the assessment and treatment of a mangled extremity is of utmost importance. These include radical tissue debridement, prophylactic antibiotics, copious irrigation with a lavage system, stable bone fixation, revascularization, nerve repair, and soft tissue coverage. Well-planned and early rehabilitation leads to a better functional outcome. Despite the use of scoring systems to help guide decisions and predict outcomes, the decision to reconstruct or to amputate still ultimately lies with the surgical judgment and experience of the treating surgeon.

  1. On the Bimodality of ENSO Cycle Extremes

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    2000-01-01

    On the basis of sea surface temperature in the El Nino 3.4 region (5 deg. N.,-5 deg. S., 120-170 deg. W.) during the interval of 1950-1997, Kevin Trenberth previously has identified some 16 El Nino and 10 La Nina, these 26 events representing the extremes of the quasi-periodic El Nino-Southern Oscillation (ENSO) cycle. Runs testing shows that the duration, recurrence period, and sequencing of these extremes vary randomly. Hence, the decade of the 1990's, especially for El Nino, is not significantly different from that of previous decadal epochs, at least, on the basis of the frequency of onsets of ENSO extremes. Additionally, the distribution of duration for both El Nino and La Nina looks strikingly bimodal, each consisting of two preferred modes, about 8- and 16-mo long for El Nino and about 9- and 18-mo long for La Nina, as does the distribution of the recurrence period for El Nino, consisting of two preferred modes about 21- and 50-mo long. Scatterplots of the recurrence period versus duration for El Nino are found to be statistically important, displaying preferential associations that link shorter (longer) duration with shorter (longer) recurrence periods. Because the last onset of El Nino occurred in April 1997 and the event was of longer than average duration, onset of the next anticipated El Nino is not expected until February 2000 or later.

  2. Drugs and drug administration in extreme environments.

    PubMed

    Küpper, Thomas E A H; Schraut, Bettina; Rieke, Burkhard; Hemmerling, Arnica-Verena; Schöffl, Volker; Steffgen, Juergen

    2006-01-01

    Emergency medicine must often cope with harsh climates far below freezing point or high temperatures, and sometimes, an alternative to the normal route of drug administration is necessary. Most of this information is not yet published. Therefore, we summarized the information about these topics for most drugs used in medical emergencies by combining literature research with extensive personal communications with the heads of the drug safety departments of the companies producing these drugs. Most drugs can be used after temperature stress of limited duration. Nevertheless, we recommend replacing them at least once per year or after extreme heat. Knowledge about drugs used in extreme environments will be of increasing importance for medical personnel because in an increasingly mobile society, more and more people, and especially elderly -often with individual medical risks-travel to extreme regions such as tropical or arctic regions or to high altitude, and some of them need medical care during these activities. Because of this increasing need to use drugs in harsh climates (tourism, expeditions, peace corps, military, etc) the actual International Congress of Harmonization recommendations should be added with stability tests at +50 degrees C, freezing and oscillating temperatures, and UV exposure to simulate the storage of the drugs at "outdoor conditions." PMID:16412107

  3. On The Bimodality of ENSO Cycle Extremes

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    2000-01-01

    On the basis of sea surface temperature in the El Nino 3.4 region (5N.-5S., 120-170W.) during the interval of 1950-1997, Kevin Trenberth previously has identified some 16 El Nino and 10 La Nina, these 26 events representing the extremes of the quasi-periodic El Nino-Southern Oscillation (ENSO) cycle. Runs testing shows that the duration, recurrence period, and sequencing of these extremes vary randomly. Hence, the decade of the 1990's, especially for El Nino, is not significantly different from that of previous decadal epochs, at least, on the basis of the frequency of onsets of ENSO extremes. Additionally, the distribution of duration for both El Nino and La Nina looks strikingly bimodal, each consisting of two preferred modes, about 8- and 16-months long for El Nino and about 9- and 18-months long for La Nina, as does the distribution of the recurrence period for El Nino, consisting of two preferred modes about 21- and 50- mo long. Scatterplots of the recurrence period versus duration for El Nino are found to be statistically important, displaying preferential associations that link shorter (longer) duration with shorter (longer) recurrence periods. Because the last onset of El Nino occurred in April 1997 and the event was of longer than average duration, onset of the next anticipated El Nino is not expected until February 2000 or later.

  4. Extreme Space Weather on Exoplanets

    NASA Astrophysics Data System (ADS)

    Cohen, O.; Drake, J. J.; Kashyap, V. L.; Glocer, A.; Garraffo, C.; Gombosi, T. I.

    2013-12-01

    The current search for exoplanets is focused on detecting Earth-like rocky planets in the habitable zone around faint, M-dwarf stars, where the definition of the habitable zone is the bounded distances from the star at which liquid water can exist on the planetary surface. However, other factors may play a role in the habitability of the planet. In particular, planets that orbit their host star in a close-in orbit, reside in an extreme space environment, where both the stellar wind and transient Coronal Mass Ejections (CMEs) can erode the planetary atmosphere. We present a detailed, three-dimensional modeling study of the space plasma physics of close-in exoplanets. The study includes the effect of the extreme space conditions on the planetary atmosphere, magnetospheric and upper atmosphere dynamics, extreme space weather on close-in planets, and star-planet magnetic interaction.

  5. Extreme hydrological events and security

    NASA Astrophysics Data System (ADS)

    Kundzewicz, Z. W.; Matczak, P.

    2015-06-01

    Economic losses caused by hydrological extremes - floods and droughts - have been on the rise, worldwide. Hydrological extremes jeopardize human security and cause serious threats to human life and welfare and societal livelihood. Floods and droughts can undermine societies' security, understood as freedom from threat and the ability of societies to maintain their independent identity and their functional integrity against forces of change. Several dimensions of security are reviewed in the context of hydrological extremes. Floods and droughts pose a burden and serious challenges to the state, responsible to sustain economic development, societal and environmental security - the maintenance of ecosystem services, on which a society depends. It is shown that reduction of risk of hydrological disasters improves human security.

  6. Functional metagenomics of extreme environments.

    PubMed

    Mirete, Salvador; Morgante, Verónica; González-Pastor, José Eduardo

    2016-04-01

    The bioprospecting of enzymes that operate under extreme conditions is of particular interest for many biotechnological and industrial processes. Nevertheless, there is a considerable limitation to retrieve novel enzymes as only a small fraction of microorganisms derived from extreme environments can be cultured under standard laboratory conditions. Functional metagenomics has the advantage of not requiring the cultivation of microorganisms or previous sequence information to known genes, thus representing a valuable approach for mining enzymes with new features. In this review, we summarize studies showing how functional metagenomics was employed to retrieve genes encoding for proteins involved not only in molecular adaptation and resistance to extreme environmental conditions but also in other enzymatic activities of biotechnological interest.

  7. Achondrogenesis type II with normally developed extremities: a case report.

    PubMed

    Kocakoc, Ercan; Kiris, Adem

    2002-07-01

    We present a case of achondrogenesis type II with normally developed extremities that was confirmed with postmortem ultrasonographic and radiographic examination. The length of the long bones may vary and the diagnosis of achondrogenesis should not be ruled out with normally developed extremities. Intrauterine sonographic examination of the vertebrae is very important and the absence of vertebral body ossification may be the unique finding of achondrogenesis type II. Axial ultrasonographic images and postmortem plain radiographs are useful to clarify the pathology. PMID:12124695

  8. Extreme value analysis in biometrics.

    PubMed

    Hüsler, Jürg

    2009-04-01

    We review some approaches of extreme value analysis in the context of biometrical applications. The classical extreme value analysis is based on iid random variables. Two different general methods are applied, which will be discussed together with biometrical examples. Different estimation, testing, goodness-of-fit procedures for applications are discussed. Furthermore, some non-classical situations are considered where the data are possibly dependent, where a non-stationary behavior is observed in the data or where the observations are not univariate. A few open problems are also stated.

  9. Extreme Conditions Modeling Workshop Report

    SciTech Connect

    Coe, R. G.; Neary, V. S.; Lawson, M. J.; Yu, Y.; Weber, J.

    2014-07-01

    Sandia National Laboratories (SNL) and the National Renewable Energy Laboratory (NREL) hosted the Wave Energy Converter (WEC) Extreme Conditions Modeling (ECM) Workshop in Albuquerque, NM on May 13th-14th, 2014. The objective of the workshop was to review the current state of knowledge on how to model WECs in extreme conditions (e.g. hurricanes and other large storms) and to suggest how U.S. Department of Energy (DOE) and national laboratory resources could be used to improve ECM methods for the benefit of the wave energy industry.

  10. Characteristics of Extreme Auroral Charging Events

    NASA Technical Reports Server (NTRS)

    Minow, Joseph I.; Willis, Emily M.; Parker, Linda Neergard

    2014-01-01

    The highest level spacecraft charging observed in low Earth orbit (LEO) occurs when spacecraft are exposed to energetic auroral electrons. Since auroral charging has been identified as a mechanism responsible for on-orbit anomalies and even possible satellite failures it is important to consider extreme auroral charging events as design and test environments for spacecraft to be used in high inclination LEO orbits. This paper will report on studies of extreme auroral charging events using data from the SSJ/4 and SSJ/5 precipitating electron and ion sensors on the Defense Meteorology Satellite Program (DMSP) satellites. Early studies of DMSP charging to negative potentials =100 V focused on statistics of the electron environment responsible for charging. Later statistical studies of auroral charging have generally focused on solar cycle dependence of charging behavior and magnitude of the maximum potential and duration of the charging events. We extend these studies to focus on more detailed investigations of extreme charging event characteristics that are required to evaluate potential threats to spacecraft systems. A collection of example auroral charging events is assembled from the DMSP data set using the criteria that "extreme auroral charging" is defined as periods with spacecraft negative potentials =400 V. Specific characteristics to be treated include (but are not limited to) maximum and mean potentials, time history of spacecraft potentials through the events, total charging duration and the time potentials exceed voltage thresholds, frame charging/discharging rates, and information on geographic and geomagnetic latitudes at which the events are observed. Finally, we will comment on the implications of these studies for potential auroral charging risks to the International Space Station.

  11. Recognizing upper-extremity stress lesions.

    PubMed

    Cervoni, T D; Martire, J R; Curl, L A; McFarland, E G

    1997-08-01

    Athletes in sports such as baseball, gymnastics, weight lifting, javelin, and racket sports are susceptible to stress lesions in the bones of the upper extremities. Injuries range from periostitis to bone spurs to stress fractures. Injuries in adolescents typically involve the growth plates, while midshaft injuries at the area of muscle insertion are more common in adults. It's especially important to detect these injuries in adolescents because untreated stress lesions at growth plates can have serious consequences. Plain films demonstrate obvious fractures and physeal injuries, but triple-phase bone scans are often needed to define the extent of stress lesions.

  12. Representing Extreme Temperature Events and Resolving Their Implications for Yield

    NASA Astrophysics Data System (ADS)

    Huybers, P. J.; Mueller, N. D.; Butler, E. E.; Tingley, M.; McKinnon, K. A.; Rhines, A. N.

    2014-12-01

    Although it is well recognized that extreme temperatures occurring at particular growth stages are destructive to yield, there appears substantial scope for improved empirical assessment and simulation of the relationship between temperature and yield. Several anecdotes are discussed. First, a statistical analysis of historical U.S. extreme temperatures is provided. It is demonstrated that both reanalysis and model simulations significantly differ from near-surface temperature observations in the frequency and magnitude of extremes. This finding supports empirical assessment using near-surface instrumental records and underscores present difficulties in simulating past and predicting future changes. Second, an analysis of the implications of extreme temperatures on U.S. maize yield is provided where the response is resolved regionally and according to growth stage. Sensitivity to extreme temperatures during silking is found to be uniformly high across the U.S., but the response during grain filling varies spatially, with higher sensitivity in the North. This regional and growth-stage dependent sensitivity implies the importance of representing cultivar, planting times, and development rates, and is also indicative of the potential for future changes according to the combined effects of climate and technology. Finally, interaction between extreme temperatures and agriculture is indicated by analysis showing that historical extreme temperatures in the U.S. Midwest have cooled in relation to changes in regional productivity, possibly because of greater potential for cooling through evapotranspiration. This interpretation is consistent with changes in crop physiology and management, though also noteworthy is that the moderating influence of increased evapotranspiration on extreme temperatures appears to be lost during severe drought. Together, these findings indicate that a more accurate assessment of the historical relationship between extreme temperatures and yield

  13. Flexible Diaphragm Withstands Extreme Temperatures

    NASA Technical Reports Server (NTRS)

    Lerma, G.

    1986-01-01

    Diaphragm seal retains flexibility throughout temperature range of -200 to +600 degree F (-129 to +316 degree C). Diaphragm durable, simple, versatile, and relatively inexpensive to manufacture. Suitable for refrigeration seals, autoclaves, storage lockers, and other sealing applications subjected to extreme temperature differentials.

  14. How Cells Endure Extreme Conditions

    SciTech Connect

    2009-01-01

    One of natures most gripping feats of survival is now better understood. For the first time, Berkeley Lab scientists observed the chemical changes in individual cells that enable them to survive in conditions that should kill them. http://newscenter.lbl.gov/feature-stories/2009/07/07/cells-endure-extremes/

  15. Patterned Growth in Extreme Environments

    NASA Astrophysics Data System (ADS)

    Curnutt, J.; Gomez, E.; Schubert, K. E.

    2009-12-01

    In this paper, cellular automata are used to model patterned growth of organisms in extreme environments. A brief introduction to cellular automaton modeling is given to assist the reader. Patterned growth of soil surface cyanobacteria and biovermiculation microbial mats in sulfuric acid caves are modeled and simulations conducted. Simulations are compared with actual systems, and future directions are discussed.

  16. Tetrasulfide extreme pressure lubricant additives

    SciTech Connect

    Gast, L.E.; Kenney, H.E.; Schwab, A.W.

    1980-08-19

    A novel class of compounds has been prepared comprising the tetrasulfides of /sup 18/C hydrocarbons, /sup 18/C fatty acids, and /sup 18/C fatty and alkyl and triglyceride esters. These tetrasulfides are useful as extreme pressure lubricant additives and show potential as replacements for sulfurized sperm whale oil.

  17. Applied extreme-value statistics

    SciTech Connect

    Kinnison, R.R.

    1983-05-01

    The statistical theory of extreme values is a well established part of theoretical statistics. Unfortunately, it is seldom part of applied statistics and is infrequently a part of statistical curricula except in advanced studies programs. This has resulted in the impression that it is difficult to understand and not of practical value. In recent environmental and pollution literature, several short articles have appeared with the purpose of documenting all that is necessary for the practical application of extreme value theory to field problems (for example, Roberts, 1979). These articles are so concise that only a statistician can recognise all the subtleties and assumptions necessary for the correct use of the material presented. The intent of this text is to expand upon several recent articles, and to provide the necessary statistical background so that the non-statistician scientist can recognize and extreme value problem when it occurs in his work, be confident in handling simple extreme value problems himself, and know when the problem is statistically beyond his capabilities and requires consultation.

  18. The Extreme Universe Space Observatory

    NASA Technical Reports Server (NTRS)

    Adams, Jim; Six, N. Frank (Technical Monitor)

    2002-01-01

    This talk will describe the Extreme Universe Space Observatory (EUSO) mission. EUSO is an ESA mission to explore the most powerful energy sources in the universe. The mission objectives of EUSO are to investigate EECRs, those with energies above 3x10(exp 19) eV, and very high-energy cosmic neutrinos. These objectives are directly related to extreme conditions in the physical world and possibly involve the early history of the big bang and the framework of GUTs. EUSO tackles the basic problem posed by the existence of these extreme-energy events. The solution could have a unique impact on fundamental physics, cosmology, and/or astrophysics. At these energies, magnetic deflection is thought to be so small that the EECR component would serve as the particle channel for astronomy. EUSO will make the first measurements of EAS from space by observing atmospheric fluorescence in the Earth's night sky. With measurements of the airshower track, EUSO will determine the energy and arrival direction of these extreme-energy events. EUSO will make high statistics observations of CRs beyond the predicted GZK cutoff energy and widen the channel for high-energy neutrino astronomy. The energy spectra, arrival directions, and shower profiles will be analyzed to distinguish the nature of these events and search for their sources. With EUSO data, we will have the possibility to discover a local EECR source, test Z-burst scenarios and other theories, and look for evidence of the breakdown of the relativity principle at extreme Lorentz factors.

  19. Extremal higher spin black holes

    NASA Astrophysics Data System (ADS)

    Bañados, Máximo; Castro, Alejandra; Faraggi, Alberto; Jottar, Juan I.

    2016-04-01

    The gauge sector of three-dimensional higher spin gravities can be formulated as a Chern-Simons theory. In this context, a higher spin black hole corresponds to a flat connection with suitable holonomy (smoothness) conditions which are consistent with the properties of a generalized thermal ensemble. Building on these ideas, we discuss a definition of black hole extremality which is appropriate to the topological character of 3 d higher spin theories. Our definition can be phrased in terms of the Jordan class of the holonomy around a non-contractible (angular) cycle, and we show that it is compatible with the zero-temperature limit of smooth black hole solutions. While this notion of extremality does not require supersymmetry, we exemplify its consequences in the context of sl(3|2) ⊕ sl(3|2) Chern-Simons theory and show that, as usual, not all extremal solutions preserve supersymmetries. Remarkably, we find in addition that the higher spin setup allows for non-extremal supersymmetric black hole solutions. Furthermore, we discuss our results from the perspective of the holographic duality between sl(3|2) ⊕ sl(3|2) Chern-Simons theory and two-dimensional CFTs with W (3|2) symmetry, the simplest higher spin extension of the N = 2 super-Virasoro algebra. In particular, we compute W (3|2) BPS bounds at the full quantum level, and relate their semiclassical limit to extremal black hole or conical defect solutions in the 3 d bulk. Along the way, we discuss the role of the spectral flow automorphism and provide a conjecture for the form of the semiclassical BPS bounds in general N = 2 two-dimensional CFTs with extended symmetry algebras.

  20. Expansion of chemical space for collaborative lead generation and drug discovery: the European Lead Factory Perspective.

    PubMed

    Karawajczyk, Anna; Giordanetto, Fabrizio; Benningshof, Jorg; Hamza, Daniel; Kalliokoski, Tuomo; Pouwer, Kees; Morgentin, Remy; Nelson, Adam; Müller, Gerhard; Piechot, Alexander; Tzalis, Dimitrios

    2015-11-01

    High-throughput screening (HTS) represents a major cornerstone of drug discovery. The availability of an innovative, relevant and high-quality compound collection to be screened often dictates the final fate of a drug discovery campaign. Given that the chemical space to be sampled in research programs is practically infinite and sparsely populated, significant efforts and resources need to be invested in the generation and maintenance of a competitive compound collection. The European Lead Factory (ELF) project is addressing this challenge by leveraging the diverse experience and know-how of academic groups and small and medium enterprises (SMEs) engaged in synthetic and/or medicinal chemistry. Here, we describe the novelty, diversity, structural complexity, physicochemical characteristics and overall attractiveness of this first batch of ELF compounds for HTS purposes. PMID:26429298

  1. Removing obstacles in neuroscience drug discovery: The future path for animal models

    PubMed Central

    Markou, Athina; Chiamulera, Christian; Geyer, Mark A.; Tricklebank, Mark; Steckler, Thomas

    2009-01-01

    Despite great advances in basic neuroscience knowledge, the improved understanding of brain functioning has not yet led to the introduction of truly novel pharmacological approaches to the treatment of central nervous system disorders. This situation has been partly attributed to the difficulty of predicting efficacy in patients based on results from preclinical studies. To address these issues, this review critically discusses the traditional role of animal models in drug discovery, the difficulties encountered, and the reasons why this approach has led to suboptimal utilization of the information animal models provide. The discussion focuses on how animal models can contribute most effectively to translational medicine and drug discovery and the changes needed to increase the probability of achieving clinical benefit. Emphasis is placed on the need to improve the flow of information from the clinical/human domain to the preclinical domain and the benefits of using truly translational measures in both preclinical and clinical testing. Few would dispute the need to move away from the concept of modeling CNS diseases in their entirety using animals. However, the current emphasis on specific dimensions of psychopathology that can be objectively assessed in both clinical populations and animal models has not yet provided concrete examples of successful preclinical-clinical translation in CNS drug discovery. The purpose of this review is to strongly encourage ever more intensive clinical and preclinical interactions to ensure that basic science knowledge gained from improved animal models with good predictive and construct validity readily becomes available to the pharmaceutical industry and clinical researchers to benefit patients as quickly as possible. PMID:18830240

  2. A global quantification of compound precipitation and wind extremes

    NASA Astrophysics Data System (ADS)

    Martius, Olivia; Pfahl, Stephan; Chevalier, Clément

    2016-07-01

    The concomitant occurrence of extreme precipitation and winds can have severe impacts. Here this concomitant occurrence is quantified globally using ERA-Interim reanalysis data. A logistic regression model is used to determine significant changes in the odds of precipitation extremes given a wind extreme that occurs on the same day, the day before, or the day after. High percentages of cooccurring wind and precipitation extremes are found in coastal regions and in areas with frequent tropical cyclones, with maxima of more than 50% of concomitant events. Strong regional-scale variations in this percentage are related to the interaction of weather systems with topography resulting in Föhn winds, gap winds, and orographic drying and the structure and tracks of extratropical and tropical cyclones. The percentage of concomitant events increases substantially if spatial shifts by one grid point are taken into account. Such spatially shifted but cooccurring events are important in insurance applications.

  3. Upper extremity function: What's posture got to do with it?

    PubMed

    Harbourne, Regina; Kamm, Kathi

    2015-01-01

    This perspective paper reviews the linkage between developing postural control and upper extremity function. We suggest updated principles for guiding clinical practice, based on current views from motor learning, motor development, and motor control research. Using three clinical examples, we illustrate principles focusing on the use of variability, the importance of errors in learning movement, task specific exploration and practice, and the critical timing necessary to build skill of the upper extremity in a variety of postures. These principles differ from historic approaches in therapeutic exercise, which treated posture as a separate system and a precursor for extremity skill building. We maintain that current movement science supports the tight interaction of posture and upper extremity function through developmental time and in real time, such that one system cannot be considered separate from the other. Specific suggestions for clinical practice flow from the guiding principles outlined in this paper. PMID:25840492

  4. Network extreme eigenvalue: From mutimodal to scale-free networks

    NASA Astrophysics Data System (ADS)

    Chung, N. N.; Chew, L. Y.; Lai, C. H.

    2012-03-01

    The extreme eigenvalues of adjacency matrices are important indicators on the influence of topological structures to the collective dynamical behavior of complex networks. Recent findings on the ensemble averageability of the extreme eigenvalue have further authenticated its applicability to the study of network dynamics. However, the ensemble average of extreme eigenvalue has only been solved analytically up to the second order correction. Here, we determine the ensemble average of the extreme eigenvalue and characterize its deviation across the ensemble through the discrete form of random scale-free network. Remarkably, the analytical approximation derived from the discrete form shows significant improvement over previous results, which implies a more accurate prediction of the epidemic threshold. In addition, we show that bimodal networks, which are more robust against both random and targeted removal of nodes, are more vulnerable to the spreading of diseases.

  5. Future crop production threatened by extreme heat

    NASA Astrophysics Data System (ADS)

    Siebert, Stefan; Ewert, Frank

    2014-04-01

    Heat is considered to be a major stress limiting crop growth and yields. While important findings on the impact of heat on crop yield have been made based on experiments in controlled environments, little is known about the effects under field conditions at larger scales. The study of Deryng et al (2014 Global crop yield response to extreme heat stress under multiple climate change futures Environ. Res. Lett. 9 034011), analysing the impact of heat stress on maize, spring wheat and soya bean under climate change, represents an important contribution to this emerging research field. Uncertainties in the occurrence of heat stress under field conditions, plant responses to heat and appropriate adaptation measures still need further investigation.

  6. On causality of extreme events

    PubMed Central

    2016-01-01

    Multiple metrics have been developed to detect causality relations between data describing the elements constituting complex systems, all of them considering their evolution through time. Here we propose a metric able to detect causality within static data sets, by analysing how extreme events in one element correspond to the appearance of extreme events in a second one. The metric is able to detect non-linear causalities; to analyse both cross-sectional and longitudinal data sets; and to discriminate between real causalities and correlations caused by confounding factors. We validate the metric through synthetic data, dynamical and chaotic systems, and data representing the human brain activity in a cognitive task. We further show how the proposed metric is able to outperform classical causality metrics, provided non-linear relationships are present and large enough data sets are available. PMID:27330866

  7. Method for extreme ultraviolet lithography

    DOEpatents

    Felter, T. E.; Kubiak, Glenn D.

    1999-01-01

    A method of producing a patterned array of features, in particular, gate apertures, in the size range 0.4-0.05 .mu.m using projection lithography and extreme ultraviolet (EUV) radiation. A high energy laser beam is used to vaporize a target material in order to produce a plasma which in turn, produces extreme ultraviolet radiation of a characteristic wavelength of about 13 nm for lithographic applications. The radiation is transmitted by a series of reflective mirrors to a mask which bears the pattern to be printed. The demagnified focused mask pattern is, in turn, transmitted by means of appropriate optics and in a single exposure, to a substrate coated with photoresists designed to be transparent to EUV radiation and also satisfy conventional processing methods.

  8. The 2014 Silba Precipitation Extreme

    NASA Astrophysics Data System (ADS)

    Rasol, Dubravka; Ólafsson, Haraldur

    2015-04-01

    On 30 July 2014 a 24 h precipitation record of 218 mm was set at the island of Silba in the N-Adriatic Sea. The precipitation was of convective nature and significantly less precipitation was recorded only small distances away, at the coast of mainland Croatia. The event is reproduced numerically and discussed in terms of dynamics and predictability. On a large scale, the precipitation extreme was associated with a slow-moving upper tropospheric low that formed over the N-Atlantic several days earlier. At lower levels, there were humid mediterranean airmasses. On a smaller scale, there are indications that the extreme convection may have been triggered by an orographic disturbance.

  9. On causality of extreme events.

    PubMed

    Zanin, Massimiliano

    2016-01-01

    Multiple metrics have been developed to detect causality relations between data describing the elements constituting complex systems, all of them considering their evolution through time. Here we propose a metric able to detect causality within static data sets, by analysing how extreme events in one element correspond to the appearance of extreme events in a second one. The metric is able to detect non-linear causalities; to analyse both cross-sectional and longitudinal data sets; and to discriminate between real causalities and correlations caused by confounding factors. We validate the metric through synthetic data, dynamical and chaotic systems, and data representing the human brain activity in a cognitive task. We further show how the proposed metric is able to outperform classical causality metrics, provided non-linear relationships are present and large enough data sets are available.

  10. Method for extreme ultraviolet lithography

    DOEpatents

    Felter, T. E.; Kubiak, G. D.

    2000-01-01

    A method of producing a patterned array of features, in particular, gate apertures, in the size range 0.4-0.05 .mu.m using projection lithography and extreme ultraviolet (EUV) radiation. A high energy laser beam is used to vaporize a target material in order to produce a plasma which in turn, produces extreme ultraviolet radiation of a characteristic wavelength of about 13 nm for lithographic applications. The radiation is transmitted by a series of reflective mirrors to a mask which bears the pattern to be printed. The demagnified focused mask pattern is, in turn, transmitted by means of appropriate optics and in a single exposure, to a substrate coated with photoresists designed to be transparent to EUV radiation and also satisfy conventional processing methods.

  11. Extreme precipitation and extreme streamflow in the Dongjiang River Basin in southern China

    NASA Astrophysics Data System (ADS)

    Wang, W.; Chen, X.; Shi, P.; van Gelder, P. H. A. J. M.; Corzo, G.

    2007-07-01

    Extreme hydro-meteorological events have become the focus of more and more studies in the last decade. Due to the complexity of the spatial pattern of changes in precipitation processes, it is still hard to establish a clear view of how precipitation has changed and how it will change in the future. In the present study, changes in extreme precipitation and streamflow processes in the Dongjiang River Basin in southern China are investigated. It was shown that little change is observed in annual extreme precipitation in terms of various indices, but some significant changes are found in the precipitation processes on a monthly basis. The result indicates that when detecting climate changes, besides annual indices, seasonal variations in extreme events should be considered as well. Despite of little change in annual extreme precipitation series, significant changes are detected in several annual extreme flood flow and low-flow series, mainly at the stations along the main channel of Dongjiang River, which are affected significantly by the operation of several major reservoirs. The result highlights the importance of evaluating the impacts of human activities in assessing the changes of extreme streamflows. In addition, three non-parametric methods that are not-commonly used by hydro-meteorology community, i.e., Kolmogorov-Smirnov test, Levene's test and quantile test, are introduced and assessed by Monte Carlo simulation in the present study to test for changes in the distribution, variance and the shift of tails of different groups of dataset. Monte Carlo simulation result shows that, while all three methods work well for detecting changes in two groups of data with large data size (e.g., over 200 points in each group) and big difference in distribution parameters (e.g., over 100% increase of scale parameter in Gamma distribution), none of them are powerful enough for small data sets (e.g., less than 100 points) and small distribution parameter difference (e.g., 50

  12. The Extreme Ultraviolet Explorer mission

    NASA Technical Reports Server (NTRS)

    Welsh, Barry Y.

    1991-01-01

    The Extreme Ultraviolet Explorer (EUVE) is a NASA astronomy mission which will operate in the 70-760A spectral band. The science payload consists of three grazing incidence scanning telescopes and an EUV spectrometer/deep survey instrument. An overview of the planned mission profile is given, and the instrumentation which comprises the science payload is discussed. The EUVE is scheduled for launch in late August 1991.

  13. Geoeffectiveness of Extreme Solar Winds

    NASA Astrophysics Data System (ADS)

    Alleyne, H.; Nanan, B.; Walker, S.; Reme, H.; Lucek, E.; Andre, M.; Cornilleau-Wehrlin, N.; Fazakerley, A.; Decreau, P.; McCrea, I.; Zhang, S.; van Eyken, A.

    2006-12-01

    The geoeffectiveness of the extreme solar winds that flowed pass the Earth on 24 October 2003, 07 November 2004 and 09 November 2004 are presented using Cluster (FGM, CIS, PEACE, STAFF and EFW) and ground- based (EISCAT radars at 69.6N, 19.2E and IMAGE magnetometer network at 68-79N)observations. The Cluster observations suggest that magnetic reconnection need not be the main process for solar wind entry into the magnetosphere during extreme solar winds. The ion velocity in the magnetosheath-cusp region remains strongly anti-sunward and poleward and ion density remains high irrespective of IMF Bz is negative or positive. The ion velocity components are also found to agree with the ExB velocities. The ground-based observations indicate that the extreme solar winds directly affect the high latitude ionosphere. The solar wind plasma is found to enter the ionosphere through an afternoon cusp that descends to low latitudes during negative IMF Bz period when a westward electrojet is also found to ascend to high latitudes.

  14. Societal Impacts of Climate Extremes

    NASA Astrophysics Data System (ADS)

    Cutter, S. L.

    2011-12-01

    Direct economic losses from weather and climate-sensitive perils in the US are on the rise averaging more than $10billion annually during the past 50 years, a very conservative estimate. Starting in the 1990s and continuing today, crop and property losses from climate extremes are escalating, especially those related to hurricanes/ tropical storms and floods. The pattern for hazard-related mortality is less clear. However, as the US lacks a comprehensive inventory or database of natural hazard losses, these figures are rough estimates. This paper examines the temporal and spatial pattern of losses from climate-sensitive hazards for the US over the past fifty years. It illustrates that how and what you measure matters in the loss calculus (dollars or deaths, insured versus uninsured losses, impacts, or costs, or extreme versus non extreme events). The paper also examines the geographic variability in losses and the differential burdens of climate hazard losses on people and places in the U.S. The paper concludes with two questions: How can the nation reduce losses from climate-sensitive hazards when we don't know how much and where such losses occur? Furthermore, how can policy makers and practitioners assess the effectiveness of any hazard or disaster risk reduction policy when we lack the fundamental baseline of losses against which to measure progress?

  15. Technology improves upper extremity rehabilitation.

    PubMed

    Kowalczewski, Jan; Prochazka, Arthur

    2011-01-01

    Stroke survivors with hemiparesis and spinal cord injury (SCI) survivors with tetraplegia find it difficult or impossible to perform many activities of daily life. There is growing evidence that intensive exercise therapy, especially when supplemented with functional electrical stimulation (FES), can improve upper extremity function, but delivering the treatment can be costly, particularly after recipients leave rehabilitation facilities. Recently, there has been a growing level of interest among researchers and healthcare policymakers to deliver upper extremity treatments to people in their homes using in-home teletherapy (IHT). The few studies that have been carried out so far have encountered a variety of logistical and technical problems, not least the difficulty of conducting properly controlled and blinded protocols that satisfy the requirements of high-level evidence-based research. In most cases, the equipment and communications technology were not designed for individuals with upper extremity disability. It is clear that exercise therapy combined with interventions such as FES, supervised over the Internet, will soon be adopted worldwide in one form or another. Therefore it is timely that researchers, clinicians, and healthcare planners interested in assessing IHT be aware of the pros and cons of the new technology and the factors involved in designing appropriate studies of it. It is crucial to understand the technical barriers, the role of telesupervisors, the motor improvements that participants can reasonably expect and the process of optimizing IHT-exercise therapy protocols to maximize the benefits of the emerging technology.

  16. Technology improves upper extremity rehabilitation.

    PubMed

    Kowalczewski, Jan; Prochazka, Arthur

    2011-01-01

    Stroke survivors with hemiparesis and spinal cord injury (SCI) survivors with tetraplegia find it difficult or impossible to perform many activities of daily life. There is growing evidence that intensive exercise therapy, especially when supplemented with functional electrical stimulation (FES), can improve upper extremity function, but delivering the treatment can be costly, particularly after recipients leave rehabilitation facilities. Recently, there has been a growing level of interest among researchers and healthcare policymakers to deliver upper extremity treatments to people in their homes using in-home teletherapy (IHT). The few studies that have been carried out so far have encountered a variety of logistical and technical problems, not least the difficulty of conducting properly controlled and blinded protocols that satisfy the requirements of high-level evidence-based research. In most cases, the equipment and communications technology were not designed for individuals with upper extremity disability. It is clear that exercise therapy combined with interventions such as FES, supervised over the Internet, will soon be adopted worldwide in one form or another. Therefore it is timely that researchers, clinicians, and healthcare planners interested in assessing IHT be aware of the pros and cons of the new technology and the factors involved in designing appropriate studies of it. It is crucial to understand the technical barriers, the role of telesupervisors, the motor improvements that participants can reasonably expect and the process of optimizing IHT-exercise therapy protocols to maximize the benefits of the emerging technology. PMID:21763524

  17. Outcomes for extremely premature infants.

    PubMed

    Glass, Hannah C; Costarino, Andrew T; Stayer, Stephen A; Brett, Claire M; Cladis, Franklyn; Davis, Peter J

    2015-06-01

    Premature birth is a significant cause of infant and child morbidity and mortality. In the United States, the premature birth rate, which had steadily increased during the 1990s and early 2000s, has decreased annually for 7 years and is now approximately 11.39%. Human viability, defined as gestational age at which the chance of survival is 50%, is currently approximately 23 to 24 weeks in developed countries. Infant girls, on average, have better outcomes than infant boys. A relatively uncomplicated course in the intensive care nursery for an extremely premature infant results in a discharge date close to the prenatal estimated date of confinement. Despite technological advances and efforts of child health experts during the last generation, the extremely premature infant (less than 28 weeks gestation) and extremely low birth weight infant (<1000 g) remain at high risk for death and disability with 30% to 50% mortality and, in survivors, at least 20% to 50% risk of morbidity. The introduction of continuous positive airway pressure, mechanical ventilation, and exogenous surfactant increased survival and spurred the development of neonatal intensive care in the 1970s through the early 1990s. Routine administration of antenatal steroids during premature labor improved neonatal mortality and morbidity in the late 1990s. The recognition that chronic postnatal administration of steroids to infants should be avoided may have improved outcomes in the early 2000s. Evidence from recent trials attempting to define the appropriate target for oxygen saturation in preterm infants suggests arterial oxygen saturation between 91% and 95% (compared with 85%-89%) avoids excess mortality; however, final analyses of data from these trials have not been published, so definitive recommendations are still pending. The development of neonatal neurocritical intensive care units may improve neurocognitive outcomes in this high-risk group. Long-term follow-up to detect and address

  18. Advanced Instrumentation for Extreme Environments

    SciTech Connect

    Melin, Alexander M; Kisner, Roger; Fugate, David L

    2013-01-01

    The Department of Energy (DOE) Office of Nuclear Energy (NE) is pursuing embedded instrumentation and controls (I&C) technology for next generation nuclear power generation applications. Embedded systems encompass a wide range of configurations and technologies; we define embedding in this instance as the integration of the sensors and the control system design into the component design using a systems engineering process. Embedded I&C systems are often an essential part of developing new capabilities, improving reliability, enhancing performance, and reducing operational costs. The new intrinsically safe, more efficient, and cost effective reactor technologies (Next Generation Nuclear Plant and Small Modular Reactors) require the development and application of new I&C technologies. These new designs raise extreme environmental challenges such as high temperatures (over 700 C) and material compatibility (e.g., molten salts). The desired reliability and functionality requires measurements in these extreme conditions including high radiation environments which were not previously monitored in real time. The DOE/NE Nuclear Energy Enabling Technologies (NEET) program currently has several projects investigating I&C technologies necessary to make these reactor designs realizable. The project described in this paper has the specific goal of investigating embedded I&C with the following objectives: 1.Explore and quantify the potential gains from embedded I&C improved reliability, increased performance, and reduced cost 2.Identify practical control, sensing, and measurement techniques for the extreme environments found in high-temperature reactors 3.Design and fabricate a functional prototype high-temperature cooling pump for molten salts represents target demonstration of improved performance, reliability, and widespread usage There are many engineering challenges in the design of a high-temperature liquid salt cooling pump. The pump and motor are in direct contact with

  19. Extreme weather events and global crop production

    NASA Astrophysics Data System (ADS)

    Ray, D. K.; Gerber, J. S.; West, P. C.

    2014-12-01

    Extreme weather events can lead to significant loss in crop production and even trigger global price spikes. However it is still not clear where exactly and what types of extreme events have resulted in sharp declines in crop production. Neither is it clear how frequently such extreme events have resulted in extreme crop production losses. Using extreme event metrics with a newly developed high resolution and long time series of crop statistics database we identify the frequency and type of extreme event driven crop production losses globally at high resolutions. In this presentation we will present our results as global maps identifying the frequency and type of extreme weather events that resulted in extreme crop production losses and quantify the losses. Understanding how extreme events affects crop production is critical for managing risk in the global food system

  20. Moving in extreme environments: extreme loading; carriage versus distance.

    PubMed

    Lucas, Samuel J E; Helge, Jørn W; Schütz, Uwe H W; Goldman, Ralph F; Cotter, James D

    2016-01-01

    This review addresses human capacity for movement in the context of extreme loading and with it the combined effects of metabolic, biomechanical and gravitational stress on the human body. This topic encompasses extreme duration, as occurs in ultra-endurance competitions (e.g. adventure racing and transcontinental races) and expeditions (e.g. polar crossings), to the more gravitationally limited load carriage (e.g. in the military context). Juxtaposed to these circumstances is the extreme metabolic and mechanical unloading associated with space travel, prolonged bedrest and sedentary lifestyle, which may be at least as problematic, and are therefore included as a reference, e.g. when considering exposure, dangers and (mal)adaptations. As per the other reviews in this series, we describe the nature of the stress and the associated consequences; illustrate relevant regulations, including why and how they are set; present the pros and cons for self versus prescribed acute and chronic exposure; describe humans' (mal)adaptations; and finally suggest future directions for practice and research. In summary, we describe adaptation patterns that are often U or J shaped and that over time minimal or no load carriage decreases the global load carrying capacity and eventually leads to severe adverse effects and manifest disease under minimal absolute but high relative loads. We advocate that further understanding of load carrying capacity and the inherent mechanisms leading to adverse effects may advantageously be studied in this perspective. With improved access to insightful and portable technologies, there are some exciting possibilities to explore these questions in this context. PMID:27110357

  1. Moving in extreme environments: extreme loading; carriage versus distance.

    PubMed

    Lucas, Samuel J E; Helge, Jørn W; Schütz, Uwe H W; Goldman, Ralph F; Cotter, James D

    2016-01-01

    This review addresses human capacity for movement in the context of extreme loading and with it the combined effects of metabolic, biomechanical and gravitational stress on the human body. This topic encompasses extreme duration, as occurs in ultra-endurance competitions (e.g. adventure racing and transcontinental races) and expeditions (e.g. polar crossings), to the more gravitationally limited load carriage (e.g. in the military context). Juxtaposed to these circumstances is the extreme metabolic and mechanical unloading associated with space travel, prolonged bedrest and sedentary lifestyle, which may be at least as problematic, and are therefore included as a reference, e.g. when considering exposure, dangers and (mal)adaptations. As per the other reviews in this series, we describe the nature of the stress and the associated consequences; illustrate relevant regulations, including why and how they are set; present the pros and cons for self versus prescribed acute and chronic exposure; describe humans' (mal)adaptations; and finally suggest future directions for practice and research. In summary, we describe adaptation patterns that are often U or J shaped and that over time minimal or no load carriage decreases the global load carrying capacity and eventually leads to severe adverse effects and manifest disease under minimal absolute but high relative loads. We advocate that further understanding of load carrying capacity and the inherent mechanisms leading to adverse effects may advantageously be studied in this perspective. With improved access to insightful and portable technologies, there are some exciting possibilities to explore these questions in this context.

  2. Quantifying the relevance of cyclones for precipitation extremes

    NASA Astrophysics Data System (ADS)

    Pfahl, S.; Wernli, H.

    2012-04-01

    Precipitation extremes and associated floods may have a huge impact on society. It is thus important to better understand the mechanisms causing these events, also with regard to their variations in a changing climate. Here the importance of a particular category of weather systems, namely cyclones, for the occurrence of regional-scale precipitation extremes is quantified globally, based on the ERA-Interim reanalysis dataset for the period 1989-2009. Such an event-based climatological approach complements previous case studies, which established the physical relationship between cyclones and heavy precipitation. Cyclones are identified from ERA-Interim sea level pressure fields as features with a finite size, determined by the outermost closed pressure contour comprising one or several pressure minima. At each grid point, the 99% percentile of six-hourly accumulated precipitation is calculated, and all dates with six-hourly precipitation larger than this percentile are identified as extreme events. A comparison with the satellite observation-based CMORPH dataset for the years 2003 to 2009 shows that ERA-Interim properly captures the timing of the extreme events in the major parts of the extratropics. A cyclone is assumed to induce a precipitation extreme if both occur simultaneously at the same grid point. The percentage of extreme precipitation events coinciding with a cyclone is then quantified at every grid point. This percentage strongly exceeds the climatological cyclone frequency in many regions. It reaches maxima of more than 80%, e.g., in the main North Atlantic, North Pacific and Southern Ocean storm track areas. Other regional hot spots of cyclone-induced precipitation extremes are found in areas with very low climatological cyclone frequencies, in particular around the Mediterranean Sea, in eastern China, over the Philippines and the southeastern United States. Our results suggest that in these hot spot regions changes of precipitation extremes with

  3. Observations of an extreme planetary system

    NASA Astrophysics Data System (ADS)

    Raetz, Stefanie; Schmidt, Tobias O. B.; Briceno, Cesar; Neuhäuser, Ralph

    2015-12-01

    Almost 500 planet host stars are already known to be surrounded by more than one planet. Most of them (except HR8799) are old and all planets were found with the same or similar detection method.We present an unique planetary system. For the first time, a close in transiting and a wide directly imaged planet are found to orbit a common host star which is a low mass member of a young open cluster. The inner candidate is the first possible young transiting planet orbiting a previously known weak-lined T-Tauri star and was detected in our international monitoring campaign of young stellar clusters. The transit shape is changing between different observations and the transit even disappears and reappears. This unusual transit behaviour can be explained by a precessing planet transiting a gravity-darkened star.The outer candidate was discovered in the course of our direct imaging survey with NACO at ESO/VLT. Both objects are consistent with a <5 Jupiter mass planet. With ~2.4 Myrs it is among the youngest exoplanet systems. Both planets orbit its star in very extreme conditions. The inner planet is very close to its Roche limiting orbital radius while the outer planet is far away from its host star at a distance of ~660 au. The detailed analysis will provide important constraints on planet formation and migration time-scales and their relation to protoplanetary disc lifetimes. Furthermore, this system with two planets on such extreme orbits gives us the opportunity to study the possible outcome of planet-planet scattering theories for the first time by observations.I will report on our monitoring and photometric follow-up observations as well as on the direct detection and the integral field spectroscopy of this extreme planetary system.

  4. Simulating multimodal seasonality in extreme daily precipitation occurrence

    NASA Astrophysics Data System (ADS)

    Tye, Mari R.; Blenkinsop, Stephen; Fowler, Hayley J.; Stephenson, David B.; Kilsby, Christopher G.

    2016-06-01

    Floods pose multi-dimensional hazards to critical infrastructure and society and these hazards may increase under climate change. While flood conditions are dependent on catchment type and soil conditions, seasonal precipitation extremes also play an important role. The extreme precipitation events driving flood occurrence may arrive non-uniformly in time. In addition, their seasonal and inter-annual patterns may also cause sequences of several events and enhance likely flood responses. Spatial and temporal patterns of extreme daily precipitation occurrence are characterized across the UK. Extreme and very heavy daily precipitation is not uniformly distributed throughout the year, but exhibits spatial differences, arising from the relative proximity to the North Atlantic Ocean or North Sea. Periods of weeks or months are identified during which extreme daily precipitation occurrences are most likely to occur, with some regions of the UK displaying multimodal seasonality. A Generalized Additive Model is employed to simulate extreme daily precipitation occurrences over the UK from 1901 to 2010 and to allow robust statistical testing of temporal changes in the seasonal distribution. Simulations show that seasonality has the strongest correlation with intra-annual variations in extreme event occurrence, while Sea Surface Temperature (SST) and Mean Sea Level Pressure (MSLP) have the strongest correlation with inter-annual variations. The north and west of the UK are dominated by MSLP in the mid-North Atlantic and the south and east are dominated by local SST. All regions now have a higher likelihood of autumnal extreme daily precipitation than earlier in the twentieth century. This equates to extreme daily precipitation occurring earlier in the autumn in the north and west, and later in the autumn in the south and east. The change in timing is accompanied by increases in the probability of extreme daily precipitation occurrences during the autumn, and in the number of

  5. A universal mechanism of extreme events and critical phenomena

    PubMed Central

    Wu, J. H.; Jia, Q.

    2016-01-01

    The occurrence of extreme events and critical phenomena is of importance because they can have inquisitive scientific impact and profound socio-economic consequences. Here we show a universal mechanism describing extreme events along with critical phenomena and derive a general expression of the probability distribution without concerning the physical details of individual events or critical properties. The general probability distribution unifies most important distributions in the field and demonstrates improved performance. The shape and symmetry of the general distribution is determined by the parameters of the fluctuations. Our work sheds judicious insights into the dynamical processes of complex systems with practical significance and provides a general approach of studying extreme and critical episodes in a combined and multidisciplinary scheme. PMID:26880219

  6. Colors of extreme exoEarth environments

    NASA Astrophysics Data System (ADS)

    Hegde, S.; Kaltenegger, L.

    2012-04-01

    The color of a planet is likely to be the first post-detection quantity to be measured for the case of direct detection of an extrasolar rocky planet in the future. Although spectroscopic studies provide detailed characteristics of a planet, the low signal-to-noise ratios that are presently achievable, limit spectroscopic measurements of distant extrasolar worlds. Filter photometry on the other hand, requires relatively low exposure times and therefore serves well as a first line of characterization for planets orbiting around distant stars. The color of a planet reveals a host of important planetary properties. Of particular interest in this regard is the characterization of the surface features that make up a planet. It is known that different surfaces on the Earth have characteristic albedos and therefore one can distinguish these surface environments of rocky planets in the visible waveband even with the help of a low-resolution color-color diagram. On Earth, extremophiles have been known to thrive under extremes of physical and geochemical conditions that are otherwise uninhabitable to most life forms. They provide us with the minimum envelope of environmental limits whilst looking for life elsewhere on a potentially habitable planet. In this talk, using a low-resolution characterization, we link the different remotely detectable surface features to the extreme forms of life that such environments could potentially harbor for cases of an aerobic as well as an anaerobic atmosphere.

  7. Fiberoptic characteristics for extreme operating environments

    NASA Technical Reports Server (NTRS)

    Delcher, R. C.

    1992-01-01

    Fiberoptics could offer several major benefits for cryogenic liquid-fueled rocket engines, including lightning immunity, weight reduction, and the possibility of implementing a number of new measurements for engine condition monitoring. The technical feasibility of using fiberoptics in the severe environments posed by cryogenic liquid-fueled rocket engines was determined. The issues of importance and subsequent requirements for this use of fiberoptics were compiled. These included temperature ranges, moisture embrittlement succeptability, and the ability to withstand extreme shock and vibration levels. Different types of optical fibers were evaluated and several types of optical fibers' ability to withstand use in cryogenic liquid-fueled rocket engines was demonstrated through environmental testing of samples. This testing included: cold-bend testing, moisture embrittlement testing, temperature cycling, temperature extremes testing, vibration testing, and shock testing. Three of five fiber samples withstood the tests to a level proving feasibility, and two of these remained intact in all six of the tests. A fiberoptic bundle was also tested, and completed testing without breakage. Preliminary cabling and harnessing for fiber protection was also demonstrated. According to cable manufacturers, the successful -300 F cold bend, vibration, and shock tests are the first instance of any major fiberoptic cable testing below roughly -55 F. This program has demonstrated the basic technical feasibility of implementing optical fibers on cryogenic liquid-fueled rocket engines, and a development plan is included highlighting requirements and issues for such an implementation.

  8. Is climate change modifying precipitation extremes?

    NASA Astrophysics Data System (ADS)

    Montanari, Alberto; Papalexiou, Simon Michael

    2016-04-01

    The title of the present contribution is a relevant question that is frequently posed to scientists, technicians and managers of local authorities. Although several research efforts were recently dedicated to rainfall observation, analysis and modelling, the above question remains essentially unanswered. The question comes from the awareness that the frequency of floods and the related socio-economic impacts are increasing in many countries, and climate change is deemed to be the main trigger. Indeed, identifying the real reasons for the observed increase of flood risk is necessary in order to plan effective mitigation and adaptation strategies. While mitigation of climate change is an extremely important issue at the global level, at small spatial scales several other triggers may interact with it, therefore requiring different mitigation strategies. Similarly, the responsibilities of administrators are radically different at local and global scales. This talk aims to provide insights and information to address the question expressed by its title. High resolution and long term rainfall data will be presented, as well as an analysis of the frequency of their extremes and its progress in time. The results will provide pragmatic indications for the sake of better planning flood risk mitigation policies.

  9. Benchmark Generation and Simulation at Extreme Scale

    SciTech Connect

    Lagadapati, Mahesh; Mueller, Frank; Engelmann, Christian

    2016-01-01

    The path to extreme scale high-performance computing (HPC) poses several challenges related to power, performance, resilience, productivity, programmability, data movement, and data management. Investigating the performance of parallel applications at scale on future architectures and the performance impact of different architectural choices is an important component of HPC hardware/software co-design. Simulations using models of future HPC systems and communication traces from applications running on existing HPC systems can offer an insight into the performance of future architectures. This work targets technology developed for scalable application tracing of communication events. It focuses on extreme-scale simulation of HPC applications and their communication behavior via lightweight parallel discrete event simulation for performance estimation and evaluation. Instead of simply replaying a trace within a simulator, this work promotes the generation of a benchmark from traces. This benchmark is subsequently exposed to simulation using models to reflect the performance characteristics of future-generation HPC systems. This technique provides a number of benefits, such as eliminating the data intensive trace replay and enabling simulations at different scales. The presented work features novel software co-design aspects, combining the ScalaTrace tool to generate scalable trace files, the ScalaBenchGen tool to generate the benchmark, and the xSim tool to assess the benchmark characteristics within a simulator.

  10. To the limit of extreme malnutrition.

    PubMed

    Frølich, Jacob; Palm, Camilla Viola Buskbjerg; Støving, Rene K

    2016-01-01

    Extreme malnutrition with body mass index (BMI) as low as 10 kg/m(2) is not uncommon in anorexia nervosa, with survival enabled through complex metabolic adaptations. In contrast, outcomes from hunger strikes and famines are usually fatal after weight loss to about 40% below expected body weight, corresponding to BMI 12 to 13 kg/m(2) in adults. Thus, many years of adaptation in adolescent-onset anorexia nervosa, supported by supplements of vitamins and treatment of intercurrent diseases, may allow survival at a much lower BMI. However, in the literature only a few cases of survival in patients with BMI <9 kg/m(2) have been described. We report on the case of a 29-y-old woman who was successfully treated in a specialized unit. She had a BMI of 7.8 kg/m(2). To our knowledge, this level of extreme malnutrition has not previously been reported. The present case emphasizes the importance of adherence to guidelines to decrease refeeding complications. PMID:26520917

  11. Communication path for extreme environments

    NASA Technical Reports Server (NTRS)

    Jorgensen, Charles C. (Inventor); Betts, Bradley J. (Inventor)

    2010-01-01

    Methods and systems for using one or more radio frequency identification devices (RFIDs), or other suitable signal transmitters and/or receivers, to provide a sensor information communication path, to provide location and/or spatial orientation information for an emergency service worker (ESW), to provide an ESW escape route, to indicate a direction from an ESW to an ES appliance, to provide updated information on a region or structure that presents an extreme environment (fire, hazardous fluid leak, underwater, nuclear, etc.) in which an ESW works, and to provide accumulated thermal load or thermal breakdown information on one or more locations in the region.

  12. Outcomes for Extremely Premature Infants

    PubMed Central

    Glass, Hannah C.; Costarino, Andrew T.; Stayer, Stephen A.; Brett, Claire; Cladis, Franklyn; Davis, Peter J.

    2015-01-01

    Premature birth is a significant cause of infant and child morbidity and mortality. In the United States, the premature birth rate, which had steadily increased during the 1990s and early 2000s, has decreased annually for four years and is now approximately 11.5%. Human viability, defined as gestational age at which the chance of survival is 50%, is currently approximately 23–24 weeks in developed countries. Infant girls, on average, have better outcomes than infant boys. A relatively uncomplicated course in the intensive care nursery for an extremely premature infant results in a discharge date close to the prenatal EDC. Despite technological advances and efforts of child health experts during the last generation, the extremely premature infant (less than 28 weeks gestation) and extremely low birth weight infant (ELBW) (< 1000 grams) remain at high risk for death and disability with 30–50% mortality and, in survivors, at least 20–50% risk of morbidity. The introduction of CPAP, mechanical ventilation, and exogenous surfactant increased survival and spurred the development of neonatal intensive care in the 1970s through the early 1990s. Routine administration of antenatal steroids during premature labor improved neonatal mortality and morbidity in the late 1990s. The recognition that chronic postnatal administration of steroids to infants should be avoided may have improved outcomes in the early 2000s. Evidence from recent trials attempting to define the appropriate target for oxygen saturation in preterm infants suggests arterial oxygen saturation between 91–95% (compared to 85–89%) avoids excess mortality. However, final analyses of data from these trials have not been published, so definitive recommendations are still pending The development of neonatal neurocognitive care visits may improve neurocognitive outcomes in this high-risk group. Long-term follow up to detect and address developmental, learning, behavioral, and social problems is critical for

  13. Materials Response under extreme conditions

    SciTech Connect

    Remington, B A; Lorenz, K T; Pollaine, S; McNaney, J M

    2005-10-06

    Solid state experiments at extreme pressures, 10-100 GPa (0.1-1 Mbar) and strain rates (10{sup 6}-10{sup 8} s{sup -1}) are being developed on high-energy laser facilities. The goal is an experimental capability to test constitutive models for high-pressure, solid-state strength for a variety of materials. Relevant constitutive models are discussed, and our progress in developing a quasi-isentropic, ramped-pressure, shockless drive is given. Designs to test the constitutive models with experiments measuring perturbation growth due to the Rayleigh-Taylor instability in solid-state samples are presented.

  14. Gravity and Extreme Magnetism SMEX

    NASA Technical Reports Server (NTRS)

    2012-01-01

    The Gravity and Extreme Magnetism SMEX mission will be the first mission to catalogue the X-ray polarisation of many astrophysical objects including black-holes and pulsars. This first of its kind mission is enabled by the novel use of a time projection chamber as an X-ray polarimeter. The detector has been developed over the last 5 years, with the current effort charged toward a demonstration of it's technical readiness to be at level 6 prior to the preliminary design review. This talk will describe the design GEMS polarimeter and the results to date from the engineering test unit.

  15. Extreme Geomagnetic Storms - 1868 - 2010

    NASA Astrophysics Data System (ADS)

    Vennerstrom, S.; Lefevre, L.; Dumbović, M.; Crosby, N.; Malandraki, O.; Patsou, I.; Clette, F.; Veronig, A.; Vršnak, B.; Leer, K.; Moretto, T.

    2016-05-01

    We present the first large statistical study of extreme geomagnetic storms based on historical data from the time period 1868 - 2010. This article is the first of two companion papers. Here we describe how the storms were selected and focus on their near-Earth characteristics. The second article presents our investigation of the corresponding solar events and their characteristics. The storms were selected based on their intensity in the aa index, which constitutes the longest existing continuous series of geomagnetic activity. They are analyzed statistically in the context of more well-known geomagnetic indices, such as the Kp and Dcx/Dst index. This reveals that neither Kp nor Dcx/Dst provide a comprehensive geomagnetic measure of the extreme storms. We rank the storms by including long series of single magnetic observatory data. The top storms on the rank list are the New York Railroad storm occurring in May 1921 and the Quebec storm from March 1989. We identify key characteristics of the storms by combining several different available data sources, lists of storm sudden commencements (SSCs) signifying occurrence of interplanetary shocks, solar wind in-situ measurements, neutron monitor data, and associated identifications of Forbush decreases as well as satellite measurements of energetic proton fluxes in the near-Earth space environment. From this we find, among other results, that the extreme storms are very strongly correlated with the occurrence of interplanetary shocks (91 - 100 %), Forbush decreases (100 %), and energetic solar proton events (70 %). A quantitative comparison of these associations relative to less intense storms is also presented. Most notably, we find that most often the extreme storms are characterized by a complexity that is associated with multiple, often interacting, solar wind disturbances and that they frequently occur when the geomagnetic activity is already elevated. We also investigate the semiannual variation in storm occurrence

  16. Analysis of WRF extreme daily precipitation over Alaska using self-organizing maps

    NASA Astrophysics Data System (ADS)

    Glisan, Justin M.; Gutowski, William J.; Cassano, John J.; Cassano, Elizabeth N.; Seefeldt, Mark W.

    2016-07-01

    We analyze daily precipitation extremes from simulations of a polar-optimized version of the Weather Research and Forecasting (WRF) model. Simulations cover 19 years and use the Regional Arctic System Model (RASM) domain. We focus on Alaska because of its proximity to the Pacific and Arctic oceans; both provide large moisture fetch inland. Alaska's topography also has important impacts on orographically forced precipitation. We use self-organizing maps (SOMs) to understand circulation characteristics conducive for extreme precipitation events. The SOM algorithm employs an artificial neural network that uses an unsupervised training process, which results in finding general patterns of circulation behavior. The SOM is trained with mean sea level pressure (MSLP) anomalies. Widespread extreme events, defined as at least 25 grid points experiencing 99th percentile precipitation, are examined using SOMs. Widespread extreme days are mapped onto the SOM of MSLP anomalies, indicating circulation patterns. SOMs aid in determining high-frequency nodes, and hence, circulations are conducive to extremes. Multiple circulation patterns are responsible for extreme days, which are differentiated by where extreme events occur in Alaska. Additionally, several meteorological fields are composited for nodes accessed by extreme and nonextreme events to determine specific conditions necessary for a widespread extreme event. Individual and adjacent node composites produce more physically reasonable circulations as opposed to composites of all extremes, which include multiple synoptic regimes. Temporal evolution of extreme events is also traced through SOM space. Thus, this analysis lays the groundwork for diagnosing differences in atmospheric circulations and their associated widespread, extreme precipitation events.

  17. Rainfall variability and extremes over southern Africa: Assessment of a climate model to reproduce daily extremes

    NASA Astrophysics Data System (ADS)

    Williams, C. J. R.; Kniveton, D. R.; Layberry, R.

    2009-04-01

    It is increasingly accepted that that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The subcontinent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of ability of a state of the art climate model to simulate climate at daily timescales is carried out using satellite derived rainfall data from the Microwave Infra-Red Algorithm (MIRA). This dataset covers the period from 1993-2002 and the whole of southern Africa at a spatial resolution of 0.1 degree longitude/latitude. The ability of a climate model to simulate current climate provides some indication of how much confidence can be applied to its future predictions. In this paper, simulations of current climate from the UK Meteorological Office Hadley Centre's climate model, in both regional and global mode, are firstly compared to the MIRA dataset at daily timescales. This concentrates primarily on the ability of the model to simulate the spatial and temporal patterns of rainfall variability over southern Africa. Secondly, the ability of the model to reproduce daily rainfall extremes will

  18. Physical examination of upper extremity compressive neuropathies.

    PubMed

    Popinchalk, Samuel P; Schaffer, Alyssa A

    2012-10-01

    A thorough history and physical examination are vital to the assessment of upper extremity compressive neuropathies. This article summarizes relevant anatomy and physical examination findings associated with upper extremity compressive neuropathies.

  19. Will extreme climatic events facilitate biological invasions?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extreme climatic events, such as intense heat waves, hurricanes, floods and droughts, can dramatically affect ecological and evolutionary processes, and more extreme events are projected with ongoing climate change. However, the implications of these events for biological invasions, which themselves...

  20. Application of RFID technology—upper extremity rehabilitation training

    PubMed Central

    Chen, Chih-Chen; Chen, Yu-Luen; Chen, Shih-Ching

    2016-01-01

    [Purpose] Upper extremity rehabilitation after an injury is very important. This study proposes radio frequency identification (RFID) technology to improve and enhance the effectiveness of the upper extremity rehabilitation. [Subjects and Methods] People use their upper extremities to conduct daily activities. When recovering from injuries, many patients neglect the importance of rehabilitation, which results in degraded function. This study recorded the training process using the traditional rehabilitation hand gliding cart with a RFID reader, RFID tags in the panel, and a servo host computer. [Results] Clinical evidence, time taken to achieve a full score, counts of missing the specified spots, and Brunnstrom stage of aided recovery, the proximal part of the upper extremity show that the RFID-based upper extremity training significantly and reduce negative impacts of the disability in daily life and activities. [Conclusion] This study combined a hand-gliding cart with an RFID reader, and when patients moved the cart, the movement could be observed via the activated RFID tags. The training data was collected and quantified for a better understanding of the recovery status of the patients. Each of the participating patients made progress as expected. PMID:27065539

  1. Application of RFID technology-upper extremity rehabilitation training.

    PubMed

    Chen, Chih-Chen; Chen, Yu-Luen; Chen, Shih-Ching

    2016-01-01

    [Purpose] Upper extremity rehabilitation after an injury is very important. This study proposes radio frequency identification (RFID) technology to improve and enhance the effectiveness of the upper extremity rehabilitation. [Subjects and Methods] People use their upper extremities to conduct daily activities. When recovering from injuries, many patients neglect the importance of rehabilitation, which results in degraded function. This study recorded the training process using the traditional rehabilitation hand gliding cart with a RFID reader, RFID tags in the panel, and a servo host computer. [Results] Clinical evidence, time taken to achieve a full score, counts of missing the specified spots, and Brunnstrom stage of aided recovery, the proximal part of the upper extremity show that the RFID-based upper extremity training significantly and reduce negative impacts of the disability in daily life and activities. [Conclusion] This study combined a hand-gliding cart with an RFID reader, and when patients moved the cart, the movement could be observed via the activated RFID tags. The training data was collected and quantified for a better understanding of the recovery status of the patients. Each of the participating patients made progress as expected. PMID:27065539

  2. Application of RFID technology-upper extremity rehabilitation training.

    PubMed

    Chen, Chih-Chen; Chen, Yu-Luen; Chen, Shih-Ching

    2016-01-01

    [Purpose] Upper extremity rehabilitation after an injury is very important. This study proposes radio frequency identification (RFID) technology to improve and enhance the effectiveness of the upper extremity rehabilitation. [Subjects and Methods] People use their upper extremities to conduct daily activities. When recovering from injuries, many patients neglect the importance of rehabilitation, which results in degraded function. This study recorded the training process using the traditional rehabilitation hand gliding cart with a RFID reader, RFID tags in the panel, and a servo host computer. [Results] Clinical evidence, time taken to achieve a full score, counts of missing the specified spots, and Brunnstrom stage of aided recovery, the proximal part of the upper extremity show that the RFID-based upper extremity training significantly and reduce negative impacts of the disability in daily life and activities. [Conclusion] This study combined a hand-gliding cart with an RFID reader, and when patients moved the cart, the movement could be observed via the activated RFID tags. The training data was collected and quantified for a better understanding of the recovery status of the patients. Each of the participating patients made progress as expected.

  3. Climatic extremes improve predictions of spatial patterns of tree species

    USGS Publications Warehouse

    Zimmermann, N.E.; Yoccoz, N.G.; Edwards, T.C.; Meier, E.S.; Thuiller, W.; Guisan, A.; Schmatz, D.R.; Pearman, P.B.

    2009-01-01

    Understanding niche evolution, dynamics, and the response of species to climate change requires knowledge of the determinants of the environmental niche and species range limits. Mean values of climatic variables are often used in such analyses. In contrast, the increasing frequency of climate extremes suggests the importance of understanding their additional influence on range limits. Here, we assess how measures representing climate extremes (i.e., interannual variability in climate parameters) explain and predict spatial patterns of 11 tree species in Switzerland. We find clear, although comparably small, improvement (+20% in adjusted D2, +8% and +3% in cross-validated True Skill Statistic and area under the receiver operating characteristics curve values) in models that use measures of extremes in addition to means. The primary effect of including information on climate extremes is a correction of local overprediction and underprediction. Our results demonstrate that measures of climate extremes are important for understanding the climatic limits of tree species and assessing species niche characteristics. The inclusion of climate variability likely will improve models of species range limits under future conditions, where changes in mean climate and increased variability are expected.

  4. Dome cities for extreme environments

    NASA Technical Reports Server (NTRS)

    Leonard, Raymond S.; Schwartz, Milton

    1992-01-01

    Extreme environments whether they be the frigid nights of the polar regions, the burning sands of the desert, or the harsh environment of space pose interesting challenges to the architect, the engineer, and the constructor in their efforts to create habitats for mankind. In space, the goals are to provide radiation protection while also providing an aesthetic living environment for long duration missions. Because of the need to provide both radiation protection and options for expansion of base facilities, a unique structural system which separates the radiation protection systems from the pressure envelope of the habitats was created. The system uses cable networks in a tensioned structural system, which supports the lunar regolith used for shielding above the facilities. The system is modular, easily expandable, and simple to construct. Additional innovations include the use of rock melting perpetrators for piles and anchoring deadmen, and various sized craters to provide side shielding. The reflective properties of the fabric used in the membrane are utilized to provide diffuse illumination. The use of craters along with the suspended shielding allows the dome to be utilized in fashions similar to those proposed by various designers unaware of the Moon's hostile radiation environment. Additional topics addressed deal with construction techniques for large domes, i.e., on the order of 100's to 1000's of meters, thermal control, the integration of tertiary water treatment schemes with architectural design, human factors, and its implications for the design of habitats for long term use in extreme environments.

  5. Extreme Low Aspect Ratio Stellarators

    NASA Astrophysics Data System (ADS)

    Moroz, Paul

    1997-11-01

    Recently proposed Spherical Stellarator (SS) concept [1] includes the devices with stellarator features and low aspect ratio, A <= 3.5, which is very unusual for stellarators (typical stellarators have A ≈ 7-10 or above). Strong bootstrap current and high-β equilibria are two distinguished elements of the SS concept leading to compact, steady-state, and efficient fusion reactor. Different coil configurations advantageous for the SS have been identified and analyzed [1-6]. In this report, we will present results on novel stellarator configurations which are unusual even for the SS approach. These are the extreme-low-aspect-ratio-stellarators (ELARS), with the aspect ratio A ≈ 1. We succeeded in finding ELARS configurations with extremely compact, modular, and simple design compatible with significant rotational transform (ι ≈ 0.1 - 0.15), large plasma volume, and good particle transport characteristics. [1] P.E. Moroz, Phys. Rev. Lett. 77, 651 (1996); [2] P.E. Moroz, Phys. Plasmas 3, 3055 (1996); [3] P.E. Moroz, D.B. Batchelor et al., Fusion Tech. 30, 1347 (1996); [4] P.E. Moroz, Stellarator News 48, 2 (1996); [5] P.E. Moroz, Plasma Phys. Reports 23, 502 (1997); [6] P.E. Moroz, Nucl. Fusion 37, No. 8 (1997). *Supported by DOE Grant No. DE-FG02-97ER54395.

  6. Dancing with Nature: Rhythm and Harmony in Extreme Sport Participation

    ERIC Educational Resources Information Center

    Brymer, Eric; Gray, Tonia

    2009-01-01

    Research on extreme sports has downplayed the importance of the athletes' connection to the natural world. This neglect stems, in part, from the assumption that these activities derive their meaning primarily from risk. The authors' long-term research reveals that the interplay between adventure athletes and the natural world is, in fact, crucial…

  7. Digital subtraction angiography in extremity trauma

    SciTech Connect

    Goodman, P.C.; Jeffrey, R.B. Jr.; Brant-Zawadzki, M.

    1984-10-01

    Digital subtraction angiography (DSA) may have considerable impact on the work-up of patients who have suffered trauma. The angiographic evaluation of vascular injuries can be accomplished rapidly and with minimal catheter use and manipulation, which is particularly important for those critically ill patients who have significant immobility because of multiple fractures. The authors retrospectively reviewed the digital subtraction angiograms in 50 consecutive cases of extremity trauma. The quality of the images in 44 of these permitted a confident diagnosis, the accuracy of which was confirmed by surgical or clinical follow-up. DSA reduces the time required to perform the procedure, the amount of contrast material injected, patient discomfort, and film cost. Its major disadvantage is the limited field size of the image intensifier.

  8. Extreme wave runup on a vertical cliff

    NASA Astrophysics Data System (ADS)

    Carbone, Francesco; Dutykh, Denys; Dudley, John M.; Dias, FréDéRic

    2013-06-01

    Wave impact and runup onto vertical obstacles are among the most important phenomena which must be taken into account in the design of coastal structures. From linear wave theory, we know that the wave amplitude on a vertical wall is twice the incident wave amplitude with weakly nonlinear theories bringing small corrections to this result. In this present study, however, we show that certain simple wave groups may produce much higher runups than previously predicted, with particular incident wave frequencies resulting in runup heights exceeding the initial wave amplitude by a factor of 5, suggesting that the notion of the design wave used in coastal structure design may need to be revisited. The results presented in this study can be considered as a note of caution for practitioners, on one side, and as a challenging novel material for theoreticians who work in the field of extreme wave-coastal structure interaction.

  9. Outcome Trajectories in Extremely Preterm Infants

    PubMed Central

    Carlo, Waldemar A.; Tyson, Jon E.; Langer, John C.; Walsh, Michele C.; Parikh, Nehal A.; Das, Abhik; Van Meurs, Krisa P.; Shankaran, Seetha; Stoll, Barbara J.; Higgins, Rosemary D.

    2012-01-01

    OBJECTIVE: Methods are required to predict prognosis with changes in clinical course. Death or neurodevelopmental impairment in extremely premature neonates can be predicted at birth/admission to the ICU by considering gender, antenatal steroids, multiple birth, birth weight, and gestational age. Predictions may be improved by using additional information available later during the clinical course. Our objective was to develop serial predictions of outcome by using prognostic factors available over the course of NICU hospitalization. METHODS: Data on infants with birth weight ≤1.0 kg admitted to 18 large academic tertiary NICUs during 1998–2005 were used to develop multivariable regression models following stepwise variable selection. Models were developed by using all survivors at specific times during hospitalization (in delivery room [n = 8713], 7-day [n = 6996], 28-day [n = 6241], and 36-week postmenstrual age [n = 5118]) to predict death or death/neurodevelopmental impairment at 18 to 22 months. RESULTS: Prediction of death or neurodevelopmental impairment in extremely premature infants is improved by using information available later during the clinical course. The importance of birth weight declines, whereas the importance of respiratory illness severity increases with advancing postnatal age. The c-statistic in validation models ranged from 0.74 to 0.80 with misclassification rates ranging from 0.28 to 0.30. CONCLUSIONS: Dynamic models of the changing probability of individual outcome can improve outcome predictions in preterm infants. Various current and future scenarios can be modeled by input of different clinical possibilities to develop individual “outcome trajectories” and evaluate impact of possible morbidities on outcome. PMID:22689874

  10. Plasma physics of extreme astrophysical environments.

    PubMed

    Uzdensky, Dmitri A; Rightley, Shane

    2014-03-01

    Among the incredibly diverse variety of astrophysical objects, there are some that are characterized by very extreme physical conditions not encountered anywhere else in the Universe. Of special interest are ultra-magnetized systems that possess magnetic fields exceeding the critical quantum field of about 44 TG. There are basically only two classes of such objects: magnetars, whose magnetic activity is manifested, e.g., via their very short but intense gamma-ray flares, and central engines of supernovae (SNe) and gamma-ray bursts (GRBs)--the most powerful explosions in the modern Universe. Figuring out how these complex systems work necessarily requires understanding various plasma processes, both small-scale kinetic and large-scale magnetohydrodynamic (MHD), that govern their behavior. However, the presence of an ultra-strong magnetic field modifies the underlying basic physics to such a great extent that relying on conventional, classical plasma physics is often not justified. Instead, plasma-physical problems relevant to these extreme astrophysical environments call for constructing relativistic quantum plasma (RQP) physics based on quantum electrodynamics (QED). In this review, after briefly describing the astrophysical systems of interest and identifying some of the key plasma-physical problems important to them, we survey the recent progress in the development of such a theory. We first discuss the ways in which the presence of a super-critical field modifies the properties of vacuum and matter and then outline the basic theoretical framework for describing both non-relativistic and RQPs. We then turn to some specific astrophysical applications of relativistic QED plasma physics relevant to magnetar magnetospheres and to central engines of core-collapse SNe and long GRBs. Specifically, we discuss the propagation of light through a magnetar magnetosphere; large-scale MHD processes driving magnetar activity and responsible for jet launching and propagation in

  11. Plasma physics of extreme astrophysical environments.

    PubMed

    Uzdensky, Dmitri A; Rightley, Shane

    2014-03-01

    Among the incredibly diverse variety of astrophysical objects, there are some that are characterized by very extreme physical conditions not encountered anywhere else in the Universe. Of special interest are ultra-magnetized systems that possess magnetic fields exceeding the critical quantum field of about 44 TG. There are basically only two classes of such objects: magnetars, whose magnetic activity is manifested, e.g., via their very short but intense gamma-ray flares, and central engines of supernovae (SNe) and gamma-ray bursts (GRBs)--the most powerful explosions in the modern Universe. Figuring out how these complex systems work necessarily requires understanding various plasma processes, both small-scale kinetic and large-scale magnetohydrodynamic (MHD), that govern their behavior. However, the presence of an ultra-strong magnetic field modifies the underlying basic physics to such a great extent that relying on conventional, classical plasma physics is often not justified. Instead, plasma-physical problems relevant to these extreme astrophysical environments call for constructing relativistic quantum plasma (RQP) physics based on quantum electrodynamics (QED). In this review, after briefly describing the astrophysical systems of interest and identifying some of the key plasma-physical problems important to them, we survey the recent progress in the development of such a theory. We first discuss the ways in which the presence of a super-critical field modifies the properties of vacuum and matter and then outline the basic theoretical framework for describing both non-relativistic and RQPs. We then turn to some specific astrophysical applications of relativistic QED plasma physics relevant to magnetar magnetospheres and to central engines of core-collapse SNe and long GRBs. Specifically, we discuss the propagation of light through a magnetar magnetosphere; large-scale MHD processes driving magnetar activity and responsible for jet launching and propagation in

  12. Lower extremity stress fractures in the military.

    PubMed

    Jacobs, Jeremy M; Cameron, Kenneth L; Bojescul, John A

    2014-10-01

    Stress fractures of the lower extremities are common among the military population and, more specifically, military recruits who partake in basic training. Both intrinsic and extrinsic factors play a role in the development of these injuries, and it is important to identify those individuals at risk early in their military careers. Some of these factors are modifiable, so they may become preventable injuries. It is important to reiterate that one stress fracture places the soldier at risk for future stress fractures; but the first injury should not be reason enough for separation from the military, as literature would support no long-term deficits from properly treated stress fractures. Early in the process, radiographic analysis is typically normal; continued pain may warrant advanced imaging, such as scintigraphy or MRI. Most stress fractures that are caught early are amendable to nonoperative management consisting of a period of immobilization and NWB followed by progressive rehabilitation to preinjury levels. Complete or displaced fractures may require operative intervention as do tension-sided FNSF. Improving dietary and preaccession physical fitness levels may play a role in reducing the incidence of stress fractures in the active-duty military population. It is important to keep in mind when evaluating soldiers and athletes who present with activity-related pain that stress fractures are not uncommon and should be given significant consideration.

  13. [Travelers exposed to extreme temperatures].

    PubMed

    Savourey, G; Bittel, J

    1997-01-01

    Sudden introduction of the unadapted human into extreme environments can result in serious, sometimes fatal, reactions. Most complications are due either to failure of thermoregulatory system or consecutive to the physiological responses to those environmental conditions. In addition to a number of minor diseases, cold can cause two major accidents, i.e., hypothermia and frostbite which can be enhanced at altitude. Moreover, the main disease in altitude conditions is represented by the acute mountain sickness which can lead to acute pulmonary and cerebral edema. Heat can cause heatstroke, dehydration, syncope, and other minor disorders. Prevention of these manifestations during stays in inhospitable climatic conditions for which the body is not suited requires knowledge of the environment and its dangers. Implementation of suitable measures can greatly reduces the incidence of adverse effects. PMID:9612745

  14. Zipf law: an extreme perspective

    NASA Astrophysics Data System (ADS)

    Eliazar, Iddo

    2016-04-01

    Extreme value theory (EVT) asserts that the Fréchet law emerges universally from linearly scaled maxima of collections of independent and identically distributed random variables that are positive-valued. Observations of many real-world sizes, e.g. city-sizes, give rise to the Zipf law: if we rank the sizes decreasingly, and plot the log-sizes versus the log-ranks, then an affine line emerges. In this paper we present an EVT approach to the Zipf law. Specifically, we establish that whenever the Fréchet law emerges from the EVT setting, then the Zipf law follows. The EVT generation of the Zipf law, its universality, and its associated phase transition, are analyzed and described in detail.

  15. Extreme solar energetic particle events

    NASA Astrophysics Data System (ADS)

    Vainio, Rami; Afanasiev, Alexandr; Battarbee, Markus

    2016-04-01

    Properties of extreme solar energetic particle (SEP) events, here defined as those leading to ground level enhancements (GLEs) of cosmic rays, are reviewed. We review recent efforts on modeling SEP acceleration to relativistic energies and present simulation results on particle acceleration at shocks driven by fast coronal mass ejections (CMEs) in different types of coronal magnetic structures and turbulent downstream compression regions. Based on these modeling results, we discuss the possible role of solar and CME parameters in the lack of GLEs during the present sunspot cycle. This work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 637324 (HESPERIA). The Academy of Finland is thanked for financial support.

  16. Extreme ultraviolet Talbot interference lithography.

    PubMed

    Li, Wei; Marconi, Mario C

    2015-10-01

    Periodic nanopatterns can be generated using lithography based on the Talbot effect or optical interference. However, these techniques have restrictions that limit their performance. High resolution Talbot lithography is limited by the very small depth of focus and the demanding requirements in the fabrication of the master mask. Interference lithography, with large DOF and high resolution, is limited to simple periodic patterns. This paper describes a hybrid extreme ultraviolet lithography approach that combines Talbot lithography and interference lithography to render an interference pattern with a lattice determined by a Talbot image. As a result, the method enables filling the arbitrary shaped cells produced by the Talbot image with interference patterns. Detailed modeling, system design and experimental results using a tabletop EUV laser are presented. PMID:26480070

  17. Causes of Extremely Fast CMEs

    NASA Technical Reports Server (NTRS)

    Feynman, Joan; Ruzmaikin, Alexander

    2006-01-01

    We study CMEs observed by LASCO to have plane of the sky velocities exceeding 1500 km/sec. We find that these extremely fast CMEs are typically associated with flares accompanied by erupting prominences. Our results are consistent with a single CME initiation process that consists of three stages. The initial stage is brought about by the emergence of new magnetic flux, which interacts with the pre-existing magnetic configuration and results in a slow rise of the magnetic structure. The second stage is a fast reconnection phase with flaring, filament eruption and a sudden increase of the rise velocity of the magnetic structure (CME). The third stage consists of propagation in the corona. We discuss the sources of these CMEs and the need for improved understanding of the first and third stages.

  18. Weather extremes could affect agriculture

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-05-01

    As Earth's climate warms, agricultural producers will need to adapt. Changes, especially increases in extreme events, are already having an impact on food production, according to speakers at a 1 May session on agriculture and food security at the AGU Science Policy Conference. Christopher Field, director of the Department of Global Ecology at the Carnegie Institution for Science of Washington, D. C., pointed out the complex factors that come into play in understanding food security, including spatially varying controls and stresses, incomplete models, and the potential for threshold responses. Factors that are likely to cause problems include increasing population; increasing preference for meat, which needs more land and energy inputs to produce; climate change; and increasing use of agricultural lands for biomass energy.

  19. Granular gases under extreme driving

    NASA Astrophysics Data System (ADS)

    Kang, W.; Machta, J.; Ben-Naim, E.

    2010-08-01

    We study inelastic gases in two dimensions using event-driven molecular-dynamics simulations. Our focus is the nature of the stationary state attained by rare injection of large amounts of energy to balance the dissipation due to collisions. We find that under such extreme driving, with the injection rate much smaller than the collision rate, the velocity distribution has a power-law high-energy tail. The numerically measured exponent characterizing this tail is in excellent agreement with predictions of kinetic theory over a wide range of system parameters. We conclude that driving by rare but powerful energy injection leads to a well-mixed gas and constitutes an alternative mechanism for agitating granular matter. In this distinct nonequilibrium steady state, energy cascades from large to small scales. Our simulations also show that when the injection rate is comparable with the collision rate, the velocity distribution has a stretched exponential tail.

  20. Carbon tetrachloride under extreme conditions

    SciTech Connect

    Pravica, Michael Sneed, Daniel; Wang, Yonggang; Smith, Quinlan; Subrahmanyam, Garimella

    2014-05-21

    We report on three experiments on carbon tetrachloride subjected to extreme conditions. In the first experiment, Raman spectra of CCl{sub 4} were acquired up to 28 GPa. Evidence was observed for at least two new phases of CCl{sub 4} above 14 GPa (phase VI) and above 22 GPa (phase VII). Decompression of the sample showed no evidence of pressure-induced decomposition. In the second experiment, a synchrotron x-ray diffraction study was performed up to 30 GPa verifying phase V and potential phases above 14 (VI) and 22 GPa (VII), respectively. In the third study, we examined irradiated CCl{sub 4} using synchrotron infrared spectroscopy to reduce fluorescent contamination. Some sort of carbon allotrope appears as a byproduct suggesting the following reaction with hard x-rays: CCl{sub 4}+ hν → C + 2Cl{sub 2}.

  1. The extreme ultraviolet explorer mission

    NASA Astrophysics Data System (ADS)

    Bowyer, S.; Malina, R. F.

    The Extreme Ultraviolet Explorer (EUVE) mission, currently scheduled for launch in September 1991, is described. The primary purpose of the mission is to survey the celestial sphere for astronomical sources of extreme ultraviolet (EUV) radiation. The survey will be accomplished with the use of three EUV telescopes, each sensitive to a different segment of the EUV band. A fourth telescope will perform a high sensitivity search of a limited sample of the sky in the shortest wavelength bands. The all-sky survey will be carried out in the first six months of the mission and will be made in four bands, or colors, λλ70-180 Å, 170-250 Å, 400-600 Å, and 500-700 Å. The second phase of the mission, conducted entirely by Guest Observers selected by NASA, will be devoted to spectroscopic observations of EUV sources. The performance of the instrument components is described. The mirrors meet the requirements of the mission, with the best mirror having a full width half energy spread of 4'' and a surface finish of 20 Å. Prototype thin film bandpass filters have been flown on the Space Shuttle and their performance optimized. Prototype detectors have been developed which have 1680 × 1680 pixel imaging capability (RMS) and up to 80% quantum efficiency. A newly invented, high efficiency grazing incidence spectrometer using variable line-space gratings will provide spectral data with ~1 Å resolution. An end-to-end model of the mission, from a stellar source to the resulting scientific data, has been constructed. Hypothetical data from astronomical sources have been processed through this model and are shown.

  2. Gut Microbiota and Extreme Longevity.

    PubMed

    Biagi, Elena; Franceschi, Claudio; Rampelli, Simone; Severgnini, Marco; Ostan, Rita; Turroni, Silvia; Consolandi, Clarissa; Quercia, Sara; Scurti, Maria; Monti, Daniela; Capri, Miriam; Brigidi, Patrizia; Candela, Marco

    2016-06-01

    The study of the extreme limits of human lifespan may allow a better understanding of how human beings can escape, delay, or survive the most frequent age-related causes of morbidity, a peculiarity shown by long-living individuals. Longevity is a complex trait in which genetics, environment, and stochasticity concur to determine the chance to reach 100 or more years of age [1]. Because of its impact on human metabolism and immunology, the gut microbiome has been proposed as a possible determinant of healthy aging [2, 3]. Indeed, the preservation of host-microbes homeostasis can counteract inflammaging [4], intestinal permeability [5], and decline in bone and cognitive health [6, 7]. Aiming at deepening our knowledge on the relationship between the gut microbiota and a long-living host, we provide for the first time the phylogenetic microbiota analysis of semi-supercentenarians, i.e., 105-109 years old, in comparison to adults, elderly, and centenarians, thus reconstructing the longest available human microbiota trajectory along aging. We highlighted the presence of a core microbiota of highly occurring, symbiotic bacterial taxa (mostly belonging to the dominant Ruminococcaceae, Lachnospiraceae, and Bacteroidaceae families), with a cumulative abundance decreasing along with age. Aging is characterized by an increasing abundance of subdominant species, as well as a rearrangement in their co-occurrence network. These features are maintained in longevity and extreme longevity, but peculiarities emerged, especially in semi-supercentenarians, describing changes that, even accommodating opportunistic and allochthonous bacteria, might possibly support health maintenance during aging, such as an enrichment and/or higher prevalence of health-associated groups (e.g., Akkermansia, Bifidobacterium, and Christensenellaceae). PMID:27185560

  3. Can reanalysis datasets describe the persistent temperature and precipitation extremes over China?

    NASA Astrophysics Data System (ADS)

    Zhu, Jian; Huang, Dan-Qing; Yan, Pei-Wen; Huang, Ying; Kuang, Xue-Yuan

    2016-08-01

    The persistent temperature and precipitation extremes may bring damage to the economy and human due to their intensity, duration and areal coverage. Understanding the quality of reanalysis datasets in descripting these extreme events is important for detection, attribution and model evaluation. In this study, the performances of two reanalysis datasets [the twentieth century reanalysis (20CR) and Interim ECMWF reanalysis (ERA-Interim)] in reproducing the persistent temperature and precipitation extremes in China are evaluated. For the persistent temperature extremes, the two datasets can better capture the intensity indices than the frequency indices. The increasing/decreasing trend of persistent warm/cold extremes has been reasonably detected by the two datasets, particularly in the northern part of China. The ERA-Interim better reproduces the climatology and tendency of persistent warm extremes, while the 20CR has better skill to depict the persistent cold extremes. For the persistent precipitation extremes, the two datasets have the ability to reproduce the maximum consecutive 5-day precipitation. The two datasets largely underestimate the maximum consecutive dry days over the northern part of China, while overestimate the maximum consecutive wet days over the southern part of China. For the response of the precipitation extremes against the temperature variations, the ERA-Interim has good ability to depict the relationship among persistent precipitation extremes, local persistent temperature extremes, and global temperature variations over specific regions.

  4. Modeling the Pineapple Express phenomenon via Multivariate Extreme Value Theory

    NASA Astrophysics Data System (ADS)

    Weller, G.; Cooley, D. S.

    2011-12-01

    The pineapple express (PE) phenomenon is responsible for producing extreme winter precipitation events in the coastal and mountainous regions of the western United States. Because the PE phenomenon is also associated with warm temperatures, the heavy precipitation and associated snowmelt can cause destructive flooding. In order to study impacts, it is important that regional climate models from NARCCAP are able to reproduce extreme precipitation events produced by PE. We define a daily precipitation quantity which captures the spatial extent and intensity of precipitation events produced by the PE phenomenon. We then use statistical extreme value theory to model the tail dependence of this quantity as seen in an observational data set and each of the six NARCCAP regional models driven by NCEP reanalysis. We find that most NCEP-driven NARCCAP models do exhibit tail dependence between daily model output and observations. Furthermore, we find that not all extreme precipitation events are pineapple express events, as identified by Dettinger et al. (2011). The synoptic-scale atmospheric processes that drive extreme precipitation events produced by PE have only recently begun to be examined. Much of the current work has focused on pattern recognition, rather than quantitative analysis. We use daily mean sea-level pressure (MSLP) fields from NCEP to develop a "pineapple express index" for extreme precipitation, which exhibits tail dependence with our observed precipitation quantity for pineapple express events. We build a statistical model that connects daily precipitation output from the WRFG model, daily MSLP fields from NCEP, and daily observed precipitation in the western US. Finally, we use this model to simulate future observed precipitation based on WRFG output driven by the CCSM model, and our pineapple express index derived from future CCSM output. Our aim is to use this model to develop a better understanding of the frequency and intensity of extreme

  5. Extreme solar particle events: The worst case scenario

    NASA Astrophysics Data System (ADS)

    Usoskin, Ilya; Kovaltsov, Gennady

    2016-04-01

    Sporadic eruptive energetic events on the Sun may occur during periods of high solar activity. Sometimes such events can be strong or even extreme posing serious hazards for the modern technology and communication dependent society. It is important to asses the worst case scenario for an extreme solar particle event and what the probability of its occurrence. The era of direct scientific exploration of the Sun is short - from few decades to a century, and yet several strong harmful events took place during that time. Can we expect even greater events? How often? What shall we prepare for? In order to answer these questions, one has to rely upon indirect methods by analyzing natural proxy archives. Here we present an overview of the history of extreme solar events in the past, from hundreds to millions of year, based on an analysis of cosmogenic isotopes in terrestrial archives (polar ice cores and tree rings) and in lunar rocks.

  6. Flood protection diversification to reduce probabilities of extreme losses.

    PubMed

    Zhou, Qian; Lambert, James H; Karvetski, Christopher W; Keisler, Jeffrey M; Linkov, Igor

    2012-11-01

    Recent catastrophic losses because of floods require developing resilient approaches to flood risk protection. This article assesses how diversification of a system of coastal protections might decrease the probabilities of extreme flood losses. The study compares the performance of portfolios each consisting of four types of flood protection assets in a large region of dike rings. A parametric analysis suggests conditions in which diversifications of the types of included flood protection assets decrease extreme flood losses. Increased return periods of extreme losses are associated with portfolios where the asset types have low correlations of economic risk. The effort highlights the importance of understanding correlations across asset types in planning for large-scale flood protection. It allows explicit integration of climate change scenarios in developing flood mitigation strategy.

  7. xSim: The Extreme-Scale Simulator

    SciTech Connect

    Boehm, Swen; Engelmann, Christian

    2011-01-01

    Investigating parallel application performance properties at scale is becoming an important part of high-performance computing (HPC) application development and deployment. The Extreme-scale Simulator (xSim) is a performance investigation toolkit that permits running an application in a controlled environment at extreme scale without the need for a respective extreme-scale HPC system. Using a lightweight parallel discrete event simulation, xSim executes a parallel application with a virtual wall clock time, such that performance data can be extracted based on a processor model and a network model. This paper presents significant enhancements to the xSim toolkit prototype that provide a more complete Message Passing Interface (MPI) support and improve its versatility. These enhancements include full virtual MPI group, communicator and collective communication support, and global variables support. The new capabilities are demonstrated by executing the entire NAS Parallel Benchmark suite in a simulated HPC environment.

  8. Imported Dengue Fever: an important reemerging disease.

    PubMed

    Courtney, Malachi; Shetty, Avinash K

    2009-11-01

    Fever in a returned traveler from the tropics often poses a diagnostic challenge to the emergency department physician because of the potential for serious morbidity and mortality associated with certain infections such as falciparum malaria and dengue. We report a case of imported dengue fever in a 15-year-old adolescent boy acquired during a recent travel to Guatemala. Dengue fever is a mosquito-transmitted viral infection of global importance. The majority of US residents with dengue become infected during travel to tropical areas. In recent years, dengue has remerged in US tropical and subtropical areas. The disease is underreported in the United States along the Mexican border. The epidemiology, clinical manifestations, diagnosis, control, and prevention of this important global reemerging infectious disease are reviewed. Clinicians should include dengue in the differential diagnosis of febrile illness in children who have recently returned from dengue endemic areas.

  9. The Extreme and Variable High Energy Sky

    NASA Astrophysics Data System (ADS)

    A critically important region of the astrophysical spectrum is the hard X-ray/gamma-ray band, from the keV to the GeV energy range. In this band, an unusually rich range of astrophysical processes occur: this is the energy domain where fundamental changes from thermal to non-thermal sources/phenomena are expected, where the effects of absorption are drastically reduced and a clearer picture of the Universe is possible. This is also the energy range where most of the extreme astrophysical behavior is taking place, e.g. cosmic acceleration, explosions and accretion onto black holes and neutron stars; where variability is more the rule than the exception and where a number of instruments are actively working (e.g. INTEGRAL, SWIFT, Suzaku, MAXI, AGILE, Fermi and HESS). These telescopes are providing an unprecedented view of the high energy sky. Combined with data obtained at lower energies from a number of satellites and ground based telescopes we have for the first time the possibility of studying this extreme and variable sky over a very broad energy band and with unprecedented sensitivity.The workshop is aimed at bringing together scientists active across the field of high energy astrophysics in order to focus on the opportunities offered by the high energy window both from the observational and theoretical viewpoints, while a dedicated section will also be devoted to discuss the current status of planned and future missions. The meeting will consist of invited talks and contributions which are welcome as either posters or as short presentations. There will be time for open discussions throughout.We intend to cover the most extreme phenomena associated with acceleration, explosions and accretion onto galactic and extragalactic objects as well as to study variability in all types of objects and environments. In view of the extension of INTEGRAL operational lifetime, the workshop will provide a unique opportunity to prepare for extra observational possibility and to

  10. Operational early warning platform for extreme meteorological events

    NASA Astrophysics Data System (ADS)

    Mühr, Bernhard; Kunz, Michael

    2015-04-01

    Operational early warning platform for extreme meteorological events Most natural disasters are related to extreme weather events (e.g. typhoons); weather conditions, however, are also highly relevant for humanitarian and disaster relief operations during and after other natural disaster like earthquakes. The internet service "Wettergefahren-Frühwarnung" (WF) provides various information on extreme weather events, especially when these events are associated with a high potential for large damage. The main focus of the platform is on Central Europe, but major events are also monitored worldwide on a daily routine. WF provides high-resolution forecast maps for many weather parameters which allow detailed and reliable predictions about weather conditions during the next days in the affected areas. The WF service became operational in February 2004 and is part of the Center for Disaster Management and Risk Reduction Technology (CEDIM) since 2007. At the end of 2011, CEDIM embarked a new type of interdisciplinary disaster research termed as forensic disaster analysis (FDA) in near real time. In case of an imminent extreme weather event WF plays an important role in CEDIM's FDA group. It provides early and precise information which are always available and updated several times during a day and gives advice and assists with articles and reports on extreme events.

  11. Characterization of extreme precipitation within atmospheric river events over California

    DOE PAGESBeta

    Jeon, S.; Prabhat,; Byna, S.; Gu, J.; Collins, W. D.; Wehner, M. F.

    2015-11-17

    Atmospheric rivers (ARs) are large, spatially coherent weather systems with high concentrations of elevated water vapor. These systems often cause severe downpours and flooding over the western coastal United States – and with the availability of more atmospheric moisture in the future under global warming we expect ARs to play an important role as potential causes of extreme precipitation changes. Therefore, we aim to investigate changes in extreme precipitation properties correlated with AR events in a warmer climate, which are large-scale meteorological patterns affecting the weather and climate of California. We have recently developed the TECA (Toolkit for Extreme Climatemore » Analysis) software for automatically identifying and tracking features in climate data sets. Specifically, we can now identify ARs that make landfall on the western coast of North America. Based on this detection procedure, we can investigate the impact of ARs by exploring the spatial extent of AR precipitation using climate model (CMIP5) simulations and characterize spatial patterns of dependence for future projections between AR precipitation extremes under climate change within the statistical framework. Our results show that AR events in the future RCP (Representative Concentration Pathway)8.5 scenario (2076–2100) tend to produce heavier rainfall with higher frequency and longer days than events from the historical run (1981–2005). We also find that the dependence between extreme precipitation events has a shorter spatial range, within localized areas in California, under the high future emissions scenario than under the historical run.« less

  12. Focus issue on the Study of Matter at Extreme Conditions

    NASA Astrophysics Data System (ADS)

    Saini, Naurang L.; Saxena, Surendra K.; Bansil, Arun

    2015-09-01

    Study of matter at extreme conditions encompasses many different approaches for understanding the physics, chemistry and materials science underlying processes, products and technologies important for society. Although extreme conditions have been associated traditionally with research in areas of geology, mineral and earth sciences, the field has expanded in the recent years to include work on energy related materials and quantum functional materials from hard to soft matter. With the motivation to engage a large number of scientists with various disciplinary interests, ranging from physics, chemistry, geophysics to materials science, the study of matter at extreme conditions has been the theme of a series of conferences hosted by the High Pressure Science Society of America (HiPSSA) and the Center for the Study of Matter at Extreme Conditions (CeSMEC) of Florida International University (FIU), Miami. These SMEC (Study of Matter at Extreme Conditions) conferences are aimed at providing a unique platform for leading researchers to meet and share cutting-edge developments, and to bridge established fields under this interdisciplinary umbrella for research on materials. The seventh meeting in the SMEC series was held during March 23-30, 2013, while sailing from Miami to the Caribbean Islands, and concluded with great enthusiasm.

  13. Estimating the extreme low-temperature event using nonparametric methods

    NASA Astrophysics Data System (ADS)

    D'Silva, Anisha

    This thesis presents a new method of estimating the one-in-N low temperature threshold using a non-parametric statistical method called kernel density estimation applied to daily average wind-adjusted temperatures. We apply our One-in-N Algorithm to local gas distribution companies (LDCs), as they have to forecast the daily natural gas needs of their consumers. In winter, demand for natural gas is high. Extreme low temperature events are not directly related to an LDCs gas demand forecasting, but knowledge of extreme low temperatures is important to ensure that an LDC has enough capacity to meet customer demands when extreme low temperatures are experienced. We present a detailed explanation of our One-in-N Algorithm and compare it to the methods using the generalized extreme value distribution, the normal distribution, and the variance-weighted composite distribution. We show that our One-in-N Algorithm estimates the one-in- N low temperature threshold more accurately than the methods using the generalized extreme value distribution, the normal distribution, and the variance-weighted composite distribution according to root mean square error (RMSE) measure at a 5% level of significance. The One-in- N Algorithm is tested by counting the number of times the daily average wind-adjusted temperature is less than or equal to the one-in- N low temperature threshold.

  14. Transcontinental hydrometeorological extremes and streamflow generation in the Pacific Coast

    NASA Astrophysics Data System (ADS)

    Munoz-Arriola, F.; Lavado, W.; Oglesby, R. J.; Rowe, C. M.; Vazquez-Aguirre, J. L.

    2013-12-01

    Streamflow is a key integrative variable of the hydrologic cycle at the basin scale. In regions along the Pacific coast of the Americas, the role of streamflow varies according to varying physical, biological, and socioeconomical contexts. Improving our understanding of the relationships between those components is a key element to improving the predictability of water availability to sustain food and energy security. However, it is still unclear how large-scale phenomena such as El Niño - Southern Oscillation affect streamflow generation along the Pacific Coast. The present work aims (a) to understand the temporal variability and spatial distribution of hydrometeorological extremes in different basins along the Pacific Coast and (b) how hydrometeorological extreme events contribute to the water year. We hypothesize that hydrometeorologic extreme contributions are to some extent regulated by ENSO, increasing their effect on streamflow generation during extreme-wet and -dry years. Hydrometeorological extreme events are estimated through the use of percentiles of precipitation and streamflow based on a GEV distribution. We assess the Sacramento River Basin (USA), Yaqui and Grijalva River Basins (Mexico) and Chillon River Basin (Perú). Preliminary results show important effects of ENSO negative phase (La Niña) on large streamflow generation in the Grijalva River Basin (Mexico), while in the Sacramento River Basin (USA), the effect is more conspicuous during El Niño, affecting the sustainability of hydropower generation and agricultural activities.

  15. Characterization of extreme precipitation within atmospheric river events over California

    NASA Astrophysics Data System (ADS)

    Jeon, S.; Prabhat; Byna, S.; Gu, J.; Collins, W. D.; Wehner, M. F.

    2015-11-01

    Atmospheric rivers (ARs) are large, spatially coherent weather systems with high concentrations of elevated water vapor. These systems often cause severe downpours and flooding over the western coastal United States - and with the availability of more atmospheric moisture in the future under global warming we expect ARs to play an important role as potential causes of extreme precipitation changes. Therefore, we aim to investigate changes in extreme precipitation properties correlated with AR events in a warmer climate, which are large-scale meteorological patterns affecting the weather and climate of California. We have recently developed the TECA (Toolkit for Extreme Climate Analysis) software for automatically identifying and tracking features in climate data sets. Specifically, we can now identify ARs that make landfall on the western coast of North America. Based on this detection procedure, we can investigate the impact of ARs by exploring the spatial extent of AR precipitation using climate model (CMIP5) simulations and characterize spatial patterns of dependence for future projections between AR precipitation extremes under climate change within the statistical framework. Our results show that AR events in the future RCP (Representative Concentration Pathway)8.5 scenario (2076-2100) tend to produce heavier rainfall with higher frequency and longer days than events from the historical run (1981-2005). We also find that the dependence between extreme precipitation events has a shorter spatial range, within localized areas in California, under the high future emissions scenario than under the historical run.

  16. An 'extreme' future for estuaries? Effects of extreme climatic events on estuarine water quality and ecology.

    PubMed

    Wetz, Michael S; Yoskowitz, David W

    2013-04-15

    Recent climate observations suggest that extreme climatic events (ECE; droughts, floods, tropical cyclones, heat waves) have increased in frequency and/or intensity in certain world regions, consistent with climate model projections that account for man's influence on the global climate system. A synthesis of existing literature is presented and shows that ECE affect estuarine water quality by altering: (1) the delivery and processing of nutrients and organic matter, (2) physical-chemical properties of estuaries, and (3) ecosystem structure and function. From the standpoint of estuarine scientists and resource managers, a major scientific challenge will be to project the estuarine response to ECE that will co-occur with other important environmental changes (i.e., natural climate variability, global warming, sea level rise, eutrophication), as this will affect the provisioning of important ecosystem services provided by estuaries.

  17. (When and where) Do extreme climate events trigger extreme ecosystem responses? - Development and initial results of a holistic analysis framework

    NASA Astrophysics Data System (ADS)

    Hauber, Eva K.; Donner, Reik V.

    2015-04-01

    In the context of ongoing climate change, extremes are likely to increase in magnitude and frequency. One of the most important consequences of these changes is that the associated ecological risks and impacts are potentially rising as well. In order to better anticipate and understand these impacts, it therefore becomes more and more crucial to understand the general connection between climate extremes and the response and functionality of ecosystems. Among other region of the world, Europe presents an excellent test case for studies concerning the interaction between climate and biosphere, since it lies in the transition region between cold polar and warm tropical air masses and thus covers a great variety of different climatic zones and associated terrestrial ecosystems. The large temperature differences across the continent make this region particularly interesting for investigating the effects of climate change on biosphere-climate interactions. However, previously used methods for defining an extreme event typically disregard the necessity of taking seasonality as well as seasonal variance appropriately into account. Furthermore, most studies have focused on the impacts of individual extreme events instead of considering a whole inventory of extremes with their respective spatio-temporal extents. In order to overcome the aforementioned research gaps, this work introduces a new approach to studying climate-biosphere interactions associated with extreme events, which comprises three consecutive steps: (1) Since Europe exhibits climatic conditions characterized by marked seasonality, a novel method is developed to define extreme events taking into account the seasonality in all quantiles of the probability distribution of the respective variable of interest. This is achieved by considering kernel density estimates individually for each observation date during the year, including the properly weighted information from adjacent dates. By this procedure, we obtain

  18. Remembrance of ecohydrologic extremes past

    NASA Astrophysics Data System (ADS)

    Band, L. E.; Hwang, T.

    2013-12-01

    Ecohydrological systems operate at time scales that span several orders of magnitude. Significant processes and feedbacks range from subdaily physiologic response to meteorological drivers, to soil forming and geomorphic processes ranging up through 10^3-10^4 years. While much attention in ecohydrology has focused on ecosystem optimization paradigms, these systems can show significant transience in structure and function, with apparent memory of hydroclimate extremes and regime shifts. While optimization feedbacks can be reconciled with system transience, a better understanding of the time scales and mechanisms of adjustment to increased hydroclimate variability and to specific events is required to understand and predict dynamics and vulnerability of ecosystems. Under certain circumstances of slowly varying hydroclimate, we hypothesize that ecosystems can remain adjusted to changing climate regimes, without displaying apparent system memory. Alternatively, rapid changes in hydroclimate and increased hydroclimate variability, amplified with well expressed non-linearity in the processes controlling feedbacks between water, carbon and nutrients, can move ecosystems far from adjusted states. The Coweeta Hydrological Laboratory is typical of humid, broadleaf forests in eastern North America, with a range of forest biomes from northern hardwoods at higher elevations, to oak-pine assemblages at lower elevations. The site provides almost 80 years of rainfall-runoff records for a set of watersheds under different management, along with multi-decadal forest plot structural information, soil moisture conditions and stream chemistry. An initial period of multi-decadal cooling, was followed by three decades of warming and increased hydroclimate variability. While mean temperature has risen over this time period, precipitation shows no long term trends in the mean, but has had a significant rise in variability with repeated extreme drought and wet periods. Over this latter

  19. Polyimide Resins Resist Extreme Temperatures

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Spacecraft and aerospace engines share a common threat: high temperature. The temperatures experienced during atmospheric reentry can reach over 2,000 F, and the temperatures in rocket engines can reach well over 5,000 F. To combat the high temperatures in aerospace applications, Dr. Ruth Pater of Langley Research Center developed RP-46, a polyimide resin capable of withstanding the most brutal temperatures. The composite material can push the service temperature to the limits of organic materials. Designed as an environmentally friendly alternative to other high-temperature resins, the RP-46 polyimide resin system was awarded a 1992 "R&D 100" award, named a "2001 NASA Technology of the Year," and later, due to its success as a spinoff technology, "2004 NASA Commercial Invention of the Year." The technology s commercial success also led to its winning the Langley s "Paul F. Holloway Technology Transfer Award" as well as "Richard T. Whitcom Aerospace Technology Transfer Award" both for 2004. RP-46 is relatively inexpensive and it can be readily processed for use as an adhesive, composite, resin molding, coating, foam, or film. Its composite materials can be used in temperatures ranging from minus 150 F to 2,300 F. No other organic materials are known to be capable of such wide range and extreme high-temperature applications. In addition to answering the call for environmentally conscious high-temperature materials, RP-46 provides a slew of additional advantages: It is extremely lightweight (less than half the weight of aluminum), chemical and moisture resistant, strong, and flexible. Pater also developed a similar technology, RP-50, using many of the same methods she used with RP-46, and very similar in composition to RP-46 in terms of its thermal capacity and chemical construction, but it has different applications, as this material is a coating as opposed to a buildable composite. A NASA license for use of this material outside of the Space Agency as well as

  20. Extremely Large Cusp Diamagnetic Cavities

    NASA Astrophysics Data System (ADS)

    Chen, J.; Fritz, T. A.

    2002-05-01

    Extremely large diamagnetic cavities with a size of as large as 6 Re have been observed in the dayside high-altitude cusp regions. Some of the diamagnetic cavities were independent of the IMF directions, which is unexpected by the current MHD (or ISM) models, suggesting that the cusp diamagnetic cavities are different from the magnetospheric sash, which provides a challenge to the existing MHD (or ISM) models. Associated with these cavities are ions with energies from 40 keV up to 8 MeV. The charge state distribution of these cusp cavity ions was indicative of their seed populations being a mixture of the ionospheric and the solar wind particles. The intensities of the cusp cavity energetic ions were observed to increase by as large as four orders of the magnitudes. During high solar wind pressure period on April 21, 1999, the POLAR spacecraft observed lower ion flux in the dayside high-latitude magnetosheath than that in the neighbouring cusp cavities. These observations indicate that the dayside high-altitude cusp diamagnetic cavity is a key region for transferring the solar wind energy, mass, and momentum into the Earth's magnetosphere. These energetic particles in the cusp diamagnetic cavity together with the cusp's connectivity have significant global impacts on the geospace environment research and will be shedding light on the long-standing unsolved fundamental issue about the origins of the energetic particles in the ring current and in upstream ion events.

  1. Extremely large cusp diamagnetic cavities

    NASA Astrophysics Data System (ADS)

    Chen, J.; Fritz, T.; Siscoe, G.

    Extremely large diamagnetic cavities with a size of as large as 6 Re have been observed in the dayside high-altitude cusp regions. These diamagnetic cavities are always there day by day. Some of the diamagnetic cavities have been observed in the morningside during intervals when the IMF By component was positive (duskward), suggesting that the cusp diamagnetic cavities are different from the magnetospheric sash predicted by MHD simulations. Associated with these cavities are ions with energies from 40 keV up to 8 MeV. The charge state distribution of these cusp cavity ions was indicative of their seed populations being a mixture of the ionospheric and the solar wind particles. The intensities of the cusp cavity energetic ions were observed to increase by as large as four orders of the magnitudes. These observations indicate that the dayside high-altitude cusp diamagnetic cavity is a key region for transferring the solar wind energy, mass, and momentum into the Earth's magnetosphere. These energetic particles in the cusp diamagnetic cavity together with the cusp's connectivity to the entire magnetopause may have significant global impacts on the geospace environment. They will possibly be shedding light on the long-standing unsolved fundamental issue about the origins of the energetic particles in the ring current and in the regions upstream of the subsolar magnetopause where energetic ion events frequently are observed.

  2. The Diffuse Extreme Ultraviolet Background

    NASA Technical Reports Server (NTRS)

    Vallerga, John; Slavin, Jonathan

    1996-01-01

    Observations of the diffuse EUV background towards 138 different directions using the spectrometers aboard the Extreme Ultraviolet Explorer satellite (EUVE) have been combined into a spectrum from 150A to 730A and represent an effective exposure of 18 million seconds. There is no significant evidence of any non-local line flux in the resultant spectrum such as that from a hot coronal plasma. These results are inconsistent with the Wisconsin C and B broad-band surveys assuming the source is a logT = 5.8 - 6.1 hot plasma in ionization equilibrium with solar abundances, confirming the previous result of Jelinksy, Vallerga and Edelstein) (hereafter Paper 1) using an observation along the ecliptic with the same instrument. To make these results consistent with the previous broad-band surveys, the plasma responsible for the emission must either be depleted in Fe by a factor of approximately 6, be behind an absorbing slab of neutral H with a column of 2 x 10(exp 19)/sq cm, or not be in collisional ionization equilibrium (CIE). One such non-CIE model (Breitswerdt and Schmutzier) that explains the soft x-ray results is also inconsistent with this EUV data.

  3. Extreme Mechanics of Growing Matter

    NASA Astrophysics Data System (ADS)

    Kuhl, Ellen

    2013-03-01

    Growth is a distinguishing feature of all living things. Unlike standard materials, living matter can autonomously respond to alterations in its environment. As a result of a continuous ultrastructural turnover and renewal of cells and extracellular matrix, living matter can undergo extreme changes in composition, size, and shape within the order of months, weeks, or days. While hard matter typically adapts by increasing its density to grow strong, soft matter adapts by increasing its volume to grow large. Here we provide a state-of-the-art review of growing matter, and compare existing mathematical models for growth and remodeling of living systems. Applications are plentiful ranging from plant growth to tumor growth, from asthma in the lungs to restenosis in the vasculature, from plastic to reconstructive surgery, and from skeletal muscle adaptation to heart failure. Using these examples, we discuss current challenges and potential future directions. We hope to initiate critical discussions around the biophysical modeling of growing matter as a powerful tool to better understand biological systems in health and disease. This research has been supported by the NSF CAREER award CMMI 0952021.

  4. The Extreme Case of Magnetars

    NASA Technical Reports Server (NTRS)

    Kouveliotou, Chryssa

    2011-01-01

    Magnetars are magnetically powered rotating neutron stars with extreme magnetic fields (over 10(exp 14) Gauss). They were discovered in the X- and gamma-rays where they predominantly emit their radiation. Very few sources (roughly 18) have been found since their discovery in 1987. NASA's Fermi Gamma-ray Space Telescope was launched June 11, 2009; since then the Fermi Gamma-ray Burst Monitor (GBM) recorded emission from four magnetar sources. Two of these were brand new sources, SGR J0501+4516, discovered with Swift and extensively monitored with Swift and GBM, SGR J0418+5729, discovered with GBM and the Interplanetary Network (IPN). A third was SGR J1550-5418, a source originally classified as an Anomalous X-ray Pulsar (AXP 1E1547.0-5408), but exhibiting a very prolific outburst with over 400 events recorded in January 2009. In my talk I will give a short history of magnetars and describe how this, once relatively esoteric field, has emerged as a link between several astrophysical areas including Gamma-Ray Bursts. Finally, I will describe the exciting new results of Fermi in this field and the current status of our knowledge of the magnetar population properties and magnetic fields.

  5. Extreme events in Uttarakhand, India

    NASA Astrophysics Data System (ADS)

    Dimri, V. P.

    2013-12-01

    Uttarakhand in NW Himalaya, India is prone to various disasters, which include earthquakes, cloud bursts, landslides, floods etc. These disasters have a cascading effect. The cloud burst results in flooding of rivers and landslides. The earthquakes shake the ground causing landslides, which sometimes block the natural path of river making artificial dams. These artificial dams can cause river flooding. The situation becomes more devastating, if heavy rainfall occurs. Such disasters are increasing in recent times. There could be several reasons for the rise in frequency of these disasters because of global and local environment changes. The global changes such as rise of global temperatures due to increase in CO2 concentration in the atmosphere can be responsible for melting of Himalayan Glaciers and changes in precipitation/ rainfall patterns etc. Anthropogenic causes such as deforestation, establishment of new townships, new hydro-power projects, mining activities etc are also making the condition more vulnerable by changing the course of river channels. A case study of such extreme event is presented. The region is affected by changes of both global and local origin, tectonically as well as climatologically.

  6. Masks for extreme ultraviolet lithography

    SciTech Connect

    Cardinale, G; Goldsmith, J; Kearney, P A; Larson, C; Moore, C E; Prisbrey, S; Tong, W; Vernon, S P; Weber, F; Yan, P-Y

    1998-09-01

    In extreme ultraviolet lithography (EUVL), the technology specific requirements on the mask are a direct consequence of the utilization of radiation in the spectral region between 10 and 15 nm. At these wavelengths, all condensed materials are highly absorbing and efficient radiation transport mandates the use of all-reflective optical systems. Reflectivity is achieved with resonant, wavelength-matched multilayer (ML) coatings on all of the optical surfaces - including the mask. The EUV mask has a unique architecture - it consists of a substrate with a highly reflective ML coating (the mask blank) that is subsequently over-coated with a patterned absorber layer (the mask). Particulate contamination on the EUVL mask surface, errors in absorber definition and defects in the ML coating all have the potential to print in the lithographic process. While highly developed technologies exist for repair of the absorber layer, no viable strategy for the repair of ML coating defects has been identified. In this paper the state-of-the-art in ML deposition technology, optical inspection of EUVL mask blank defects and candidate absorber patterning approaches are reviewed.

  7. Gravity and Extreme Magnetism SMEX

    NASA Technical Reports Server (NTRS)

    Swank, Jean; Kallman, Timothy R.; Jahoda, Keith M.

    2008-01-01

    Gas accreting ont,o black holes and neutron stars form a dynamic system generating X-rays with spectroscopic signatures and varying on time scales determined by the system. The radiation from various parts of these systems is surely polarized and compact sources have been calculated to give rise to net polarization from the unresolved sum of the radiation from the systems. Polarization has been looked to for some time as also bearing the imprint of strong gravity and providing complementary information that could resolve ambiguities between the physical models that can give rise to frequencies, time delays, and spectra. In the cases of both stellar black holes and supermassive black holes the net polarizations predicted for probable disk and corona models are less than 10 needed. This sensitivity can be achieved, even for sources as faint as 1 milliCrab, in the Gravity and Extreme Magnetism SMEX (GEMS) mission that uses foil mirrors and Time Projection Chamber detectors. Similarities have been pointed out between the timing and the spectral characteristics of low mass X-ray binaries and stellar black hole sources. Polarization measurements for these sources could play a role in determining the configuration of the disk and the neutron star.

  8. Science of Extreme Light Infrastructure

    NASA Astrophysics Data System (ADS)

    Tajima, Toshiki; Barish, Barry C.; Barty, C. P.; Bulanov, Sergei; Chen, Pisin; Feldhaus, Josef; Hajdu, Janos; Keitel, Christoph H.; Kieffer, Jean-Claude; Ko, Do-Kyeong; Leemans, Wim; Normand, Didier; Palumbo, Luigi; Rzazewski, Kazimierz; Sergeev, Alexander; Sheng, Zheng-Ming; Takasaki, Fumihiko; Teshima, Masahiro

    2010-04-01

    The infrastructure of Extreme Light Infrastructure (ELI) provides an unprecedented opportunity for a broad range of frontier science. Its highest ever intensity of lasers, as well as high fluence, high power, and/or ultrafast optical characteristics carve out new territories of discovery, ranging from attosecond science to photonuclear science, laser acceleration and associated beams, and high field science (Four Pillars of ELI). Its applications span from medicine, biology, engineering, energy, chemistry, physics, and fundamental understanding of the Universe. The relativistic optics that intense lasers have begun exploring may be extended into a new regime of ultra-relativistic regime, where even protons fly relativistically in the optical fields. ELI provides the highest intensity to date such that photon fields begin to feel even the texture of vacuum. This is a singular appeal of ELI with its relatively modest infrastructure (compared to the contemporary largest scientific infrastructures), yet provides an exceptional avenue along which the 21st Century science and society need to answer the toughest questions. The intensity frontier simultaneously brings in the energy horizon (TeV and PeV) as well as temporal frontier (attoseconds and zeptoseconds). It also turns over optics of atoms and molecules into that of nuclei with the ability to produce monoenergetic collimated γ-ray photons. As such, the ELI concept acutely demands an effort to encompass and integrate its Four Pillars.

  9. Driving Extreme Efficiency to Market

    NASA Astrophysics Data System (ADS)

    Garbesi, Karina

    2014-03-01

    The rapid development of extremely energy efficient appliances and equipment is essential to curtail catastrophic climate disruption. This will require the on-going development of products that apply all best-practices and that take advantage of the synergies of hybridization and building integration. Beyond that, it requires the development of new disruptive technologies and concepts. To facilitate these goals, in 2011 the Lawrence Berkeley National Laboratory and the U.S. Department of Energy launched the Max Tech and Beyond Design Competition for Ultra-Low-Energy-Use Appliances and Equipment. Now in its third year, the competition supports faculty-lead student design teams at U.S. universities to develop and test new technology prototypes. This talk describes what the competition and the Max Tech Program are doing to drive such rapid technology progress and to facilitate the entry to the market of successful Max Tech prototypes. The talk also initiates a discussion of physicists' unique role in driving that technology progress faster and farther. Emerging Technologies, Building Technologies Office, U.S. Department of Energy.

  10. Extreme Programming in a Research Environment

    NASA Technical Reports Server (NTRS)

    Wood, William A.; Kleb, William L.

    2002-01-01

    This article explores the applicability of Extreme Programming in a scientific research context. The cultural environment at a government research center differs from the customer-centric business view. The chief theoretical difficulty lies in defining the customer to developer relationship. Specifically, can Extreme Programming be utilized when the developer and customer are the same person? Eight of Extreme Programming's 12 practices are perceived to be incompatible with the existing research culture. Further, six of the nine 'environments that I know don't do well with XP' apply. A pilot project explores the use of Extreme Programming in scientific research. The applicability issues are addressed and it is concluded that Extreme Programming can function successfully in situations for which it appears to be ill-suited. A strong discipline for mentally separating the customer and developer roles is found to be key for applying Extreme Programming in a field that lacks a clear distinction between the customer and the developer.

  11. [Injury mechanisms in extreme violence settings].

    PubMed

    Arcaute-Velazquez, Fernando Federico; García-Núñez, Luis Manuel; Noyola-Vilallobos, Héctor Faustino; Espinoza-Mercado, Fernando; Rodríguez-Vega, Carlos Eynar

    2016-01-01

    Extreme violence events are consequence of current world-wide economic, political and social conditions. Injury patterns found among victims of extreme violence events are very complex, obeying several high-energy injury mechanisms. In this article, we present the basic concepts of trauma kinematics that regulate the clinical approach to victims of extreme violence events, in the hope that clinicians increase their theoretical armamentarium, and reflecting on obtaining better outcomes.

  12. Changes in extreme dry and wet precipitation spell

    NASA Astrophysics Data System (ADS)

    Papalexiou, Simon Michael; Foufoula-Georgiou, Efi; Onof, Chris

    2016-04-01

    Global warming is expected to alter the behavior of hydroclimatic variables in various ways. Therefore, it is of great importance not only to identify which hydroclimatic variables are going through changes but also which of their specific characteristics change and in what way. For example the major focus regarding precipitation has been on changes or trends in extreme events or in annual totals, obviously, not without a reason. Yet one of the aspects of precipitation we believe is of equal importance and has not been extensively studied is extreme dry and wet spells. Changes in dry and wet spells can severely impact all aspects of human lives, ranging from infrastructure planning and water resources management to agriculture and infectious disease spread. In this study we perform an extensive analysis of extreme dry and wet precipitation spells using tenths of thousands of daily precipitation records in order to identify trends or variability changes in the maximum number of consecutive dry or wet days of each year. Our final goal is to evaluate the percentage of stations globally with positive/negative trends either in the mean value or in variability of extreme dry and wet spells and assess if this percentage is statistically justifiable.

  13. Investigation on rainfall extremes events trough a geoadditive model

    NASA Astrophysics Data System (ADS)

    Bocci, C.; Caporali, E.; Petrucci, A.; Rossi, G.

    2012-04-01

    Rainfall can be considered a very important variable, and rainfall extreme events analysis of great concern for the enormous impacts that they may have on everyday life particularly when related to intense rainfalls and floods, and hydraulic risk management. On the catchment area of Arno River in Tuscany, Central Italy, a geoadditive mixed model of rainfall extremes is developed. Most of the territory of Arno River has suffered in the past of many severe hydro-geological events, with high levels of risk due to the vulnerability of a unique artistic and cultural heritage. The area has a complex topography that greatly influences the precipitation regime. The dataset is composed by the time series of the annual maxima of daily rainfall recorded in about 400 rain gauges, spatially distributed over the catchment area of about 8.800 km2. The record period covers mainly the second half of 20th century. The rainfall observations are assumed to follow generalized extreme value distributions whose locations are spatially dependent and where the dependence is captured using a geoadditive model. In particular, since rainfall has a natural spatial domain and a significant spatial variability, a spatial hierarchical model for extremes is used. The spatial hierarchical models, in fact, take into account data from all locations, borrowing strength from neighbouring locations when they estimate parameters and are of great interest when small set of data is available, as in the case of rainfall extreme values. Together with rain gauges location variables further physiographic variables are investigated as explanation variables. The implemented geoadditive mixed model of spatially referenced time series of rainfall extreme values, is able to capture the spatial dynamics of the rainfall extreme phenomenon. Since the model shows evidence of a spatial trend in the rainfall extreme dynamic, the temporal dynamic and the time influence can be also taken into account. The implemented

  14. Real World: Analog Testing in Extreme Environments

    NASA Video Gallery

    See how NASA uses analog testing to simulate space exploration. Explore extreme environments like the Aquarius underwater laboratory in Key Largo, Florida. Find out how scientists use mathematical ...

  15. Peripheral nerve blocks for distal extremity surgery.

    PubMed

    Offierski, Chris

    2013-10-01

    Peripheral nerve block is well suited for distal extremity surgery. Blocking the nerves at the distal extremity is easily done. It does not require ultrasound or stimulators to identify the nerve. Blocking nerves in the distal extremity is safe with low risk of toxicity. The effect of the nerve block is limited to the distribution of the nerve. The distal nerves in the lower extremity are sensory branches of the sciatic nerve. This provides a sensory block only. This has the advantage of allowing the patient to actively contract tendons in the foot and ambulate more quickly after surgery. PMID:24093651

  16. The limits for life under multiple extremes.

    PubMed

    Harrison, Jesse P; Gheeraert, Nicolas; Tsigelnitskiy, Dmitry; Cockell, Charles S

    2013-04-01

    Life on Earth is limited by physical and chemical extremes that define the 'habitable space' within which it operates. Aside from its requirement for liquid water, no definite limits have been established for life under any extreme. Here, we employ growth data published for 67 prokaryotic strains to explore the limitations for microbial life under combined extremes of temperature, pH, salt (NaCl) concentrations, and pressure. Our review reveals a fundamental lack of information on the tolerance of microorganisms to multiple extremes that impedes several areas of science, ranging from environmental and industrial microbiology to the search for extraterrestrial life. PMID:23453124

  17. Characteristics of Extreme Summer Convection over equatorial America and Africa

    NASA Astrophysics Data System (ADS)

    Zuluaga, M. D.; Houze, R.

    2013-12-01

    cases over tropical America. Over Africa the monsoon is also important in modulating the occurrence of extreme convection; however, diurnal heating and the passage of African Easterly Waves are of primary importance in distributing the extreme convection zonally across the tropical African savannas.

  18. War injuries of the extremities.

    PubMed

    Korzinek, K

    1993-05-01

    This paper describes experience acquired during the war against Croatia under improvised conditions at the Kutina War Hospital in the immediate vicinity of the first front lines. Over a period of almost 6 months a total of 701 soldiers and civilians, 546 of whom had been wounded by firearm missiles, were treated at the Kutina War Hospital, which has a capacity of 30-40 beds. As many as 87% of the injuries were due to mine, bomb or artillery shell shrapnel. The percentage of gunshot wounds was very low, mainly caused by sniper shots. Most patients (419, or 76.7%) were admitted with injuries to the extremities, including 893 severe soft tissue injuries and 182 fractures (32.3%). Soft tissue injuries were treated by routine procedures of war surgery, associated with ample use of Lavasept, an antiseptic solution (Fresenius, Stans, Switzerland), which has proved to be highly efficacious in preventing and decontaminating infection without disturbance of the wound healing process. Long bone fractures were fixed with the aid of external fixators of various designs, including the CMC external fixator of our own construction. External fixators have once again proved indispensable in the treatment of open fractures sustained in war settings. Amputations were performed in 10.4% of cases, including fingers and toes. Only 8 patients died during or immediately after surgery, corresponding to a very low mortality rate of 1.46%. The main prerequisites for successful treatment are a professional relationship to war surgery and its specific requirements, satisfactory technical equipment, and excellent organization of medical and non-medical services.

  19. Magnetotactic Bacteria from Extreme Environments

    NASA Astrophysics Data System (ADS)

    Bazylinski, Dennis A.; Lefère, Christopher T.

    2013-03-01

    Magnetotactic bacteria (MTB) represent a diverse collection of motile prokaryotes that biomineralize intracellular, membrane-bounded, tens-of-nanometer-sized crystals of a magnetic mineral called magnetosomes. Magnetosome minerals consist of either magnetite (Fe3O4) or greigite (Fe3S4) and cause cells to align along the Earth's geomagnetic field lines as they swim, a trait called magnetotaxis. MTB are known to mainly inhabit the oxic-anoxic interface (OAI) in water columns or sediments of aquatic habitats and it is currently thought that magnetosomes function as a means of making chemotaxis more efficient in locating and maintaining an optimal position for growth and survival at the OAI. Known cultured and uncultured MTB are phylogenetically associated with the Alpha-, Gamma- and Deltaproteobacteria classes of the phylum Proteobacteria, the Nitrospirae phylum and the candidate division OP3, part of the Planctomycetes-Verrucomicrobia-Chlamydiae (PVC) bacterial superphylum. MTB are generally thought to be ubiquitous in aquatic environments as they are cosmopolitan in distribution and have been found in every continent although for years MTB were thought to be restricted to habitats with pH values near neutral and at ambient temperature. Recently, however, moderate thermophilic and alkaliphilic MTB have been described including: an uncultured, moderately thermophilic magnetotactic bacterium present in hot springs in northern Nevada with a probable upper growth limit of about 63 °C; and several strains of obligately alkaliphilic MTB isolated in pure culture from different aquatic habitats in California, including the hypersaline, extremely alkaline Mono Lake, with an optimal growth pH of >9.0.

  20. Magnetotactic Bacteria from Extreme Environments

    PubMed Central

    Bazylinski, Dennis A.; Lefèvre, Christopher T.

    2013-01-01

    Magnetotactic bacteria (MTB) represent a diverse collection of motile prokaryotes that biomineralize intracellular, membrane-bounded, tens-of-nanometer-sized crystals of a magnetic mineral called magnetosomes. Magnetosome minerals consist of either magnetite (Fe3O4) or greigite (Fe3S4) and cause cells to align along the Earth’s geomagnetic field lines as they swim, a trait called magnetotaxis. MTB are known to mainly inhabit the oxic–anoxic interface (OAI) in water columns or sediments of aquatic habitats and it is currently thought that magnetosomes function as a means of making chemotaxis more efficient in locating and maintaining an optimal position for growth and survival at the OAI. Known cultured and uncultured MTB are phylogenetically associated with the Alpha-, Gamma- and Deltaproteobacteria classes of the phylum Proteobacteria, the Nitrospirae phylum and the candidate division OP3, part of the Planctomycetes-Verrucomicrobia-Chlamydiae (PVC) bacterial superphylum. MTB are generally thought to be ubiquitous in aquatic environments as they are cosmopolitan in distribution and have been found in every continent although for years MTB were thought to be restricted to habitats with pH values near neutral and at ambient temperature. Recently, however, moderate thermophilic and alkaliphilic MTB have been described including: an uncultured, moderately thermophilic magnetotactic bacterium present in hot springs in northern Nevada with a probable upper growth limit of about 63 °C; and several strains of obligately alkaliphilic MTB isolated in pure culture from different aquatic habitats in California, including the hypersaline, extremely alkaline Mono Lake, with an optimal growth pH of >9.0. PMID:25369742

  1. Recent high mountain rockfalls and warm daily temperature extremes

    NASA Astrophysics Data System (ADS)

    Allen, S. K.; Huggel, C.

    2012-04-01

    temperatures in the 7 days prior to failure, (between 6 - 9°C above average), and in three of these cases, temperatures exceeded even the 99th percentile. A further 3 events occurring in this region during the longer term heatwave of 2003 similarly were also preceded by extreme daily maximum temperatures. This relationship holds for other failures analysed in the northern, and eastern regions of the central Alps. Most interestingly, the weekly temperature anomaly, and the proportion of 'extreme' days, generally decreases as the analyses are extended from 1, 2, 3 and 4 weeks out from each failure. In other words, there is a notable warming, and conditions become increasingly extreme in the lead-up to slope failure. In addition to extreme summer temperatures, our analyses points towards a possible role of unusually warm autumn and spring days influencing slope stability. A linkage between short term periods of extremely warm temperatures and rock failure may be reasonably facilitated through melt water operating within rock discontinues, processes that have recently been measured in high-mountain rock faces, and are considered to be particularly important in spring/early summer melt periods. It is not clear whether slope failures during warm autumn periods can be linked to the same processes. Rockfalls in the winter months remain rare, however, the 27 December 2011 rock avalanche at Piz Cengalo, Val Bregaglia, Switzerland (ca 2-3million m3), occurred following the warmest year on record, potentially reinforcing the role of longer term warming destabilising bedrock with permafrost at depth.

  2. An influence of extremal edges on boundary extension.

    PubMed

    Hale, Ralph G; Brown, James M; McDunn, Benjamin A; Siddiqui, Aisha P

    2015-08-01

    Studies have shown that people consistently remember seeing more of a studied scene than was physically present (e.g., Intraub & Richardson Journal of Experimental Psychology: Learning, Memory, and Cognition, 15, 179-187, 1989). This scene memory error, known as boundary extension, has been suggested to occur due to an observer's failure to differentiate between the contributing sources of information, including the sensory input, amodal continuation beyond the view boundaries, and contextual associations with the main objects and depicted scene locations (Intraub, 2010). Here, "scenes" made of abstract shapes on random-dot backgrounds, previously shown to elicit boundary extension (McDunn, Siddiqui, & Brown Psychonomic Bulletin & Review, 21, 370-375, 2014), were compared with versions made with extremal edges (Palmer & Ghose Psychological Science, 19, 77-84, 2008) added to their borders, in order to examine how boundary extension is influenced when amodal continuation at the borders' view boundaries is manipulated in this way. Extremal edges were expected to reduce boundary extension as compared to the same scenes without them, because extremal edge boundaries explicitly indicate an image's end (i.e., they do not continue past the view boundary). A large and a small difference (16 % and 40 %) between the close and wide-angle views shown during the experiment were tested to examine the effects of both boundary extension and normalization with and without extremal edges. Images without extremal edges elicited typical boundary extension for the 16 % size change condition, whereas the 40 % condition showed signs of normalization. With extremal edges, a reduced amount of boundary extension occurred for the 16 % condition, and only normalization was found for the 40 % condition. Our findings support and highlight the importance of amodal continuation at the view boundaries as a component of boundary extension.

  3. Staff Radiation Doses to the Lower Extremities in Interventional Radiology

    SciTech Connect

    Shortt, C. P.; Al-Hashimi, H.; Malone, L.; Lee, M. J.

    2007-11-15

    The purpose of this study was to investigate the radiation doses to the lower extremities in interventional radiology suites and evaluate the benefit of installation of protective lead shielding. After an alarmingly increased dose to the lower extremity in a preliminary study, nine interventional radiologists wore thermoluminescent dosimeters (TLDs) just above the ankle, over a 4-week period. Two different interventional suites were used with Siemens undercouch fluoroscopy systems. A range of procedures was carried out including angiography, embolization, venous access, drainages, and biopsies. A second identical 4-week study was then performed after the installation of a 0.25-mm lead curtain on the working side of each interventional table. Equivalent doses for all nine radiologists were calculated. One radiologist exceeded the monthly dose limit for a Category B worker (12.5 mSv) for both lower extremities before lead shield placement but not afterward. The averages of both lower extremities showed a statistically significant dose reduction of 64% (p < 0.004) after shield placement. The left lower extremity received a higher dose than the right, 6.49 vs. 4.57 mSv, an increase by a factor of 1.42. Interventional radiology is here to stay but the benefits of interventional radiology should never distract us from the important issue of radiation protection. All possible measures should be taken to optimize working conditions for staff. This study showed a significant lower limb extremity dose reduction with the use of a protective lead curtain. This curtain should be used routinely on all C-arm interventional radiologic equipment.

  4. Adolescent baseball pitching technique: lower extremity biomechanical analysis.

    PubMed

    Milewski, Matthew D; Õunpuu, Sylvia; Solomito, Matthew; Westwell, Melany; Nissen, Carl W

    2012-11-01

    Documentation of the lower extremity motion patterns of adolescent pitchers is an important part of understanding the pitching motion and the implication of lower extremity technique on upper extremity loads, injury and performance. The purpose of this study was to take the initial step in this process by documenting the biomechanics of the lower extremities during the pitching cycle in adolescent pitchers and to compare these findings with the published data for older pitchers. Three-dimensional motion analysis using a comprehensive lower extremity model was used to evaluate the fast ball pitch technique in adolescent pitchers. Thirty-two pitchers with a mean age of 12.4 years (range 10.5-14.7 years) and at least 2 years of experience were included in this study. The pitchers showed a mean of 49 ± 12° of knee flexion of the lead leg at foot contact. They tended to maintain this position through ball release, and then extended their knee during the follow through phase (ball release to maximal internal glenohumeral rotation). The lead leg hip rapidly progressed into adduction and flexion during the arm cocking phase with a range of motion of 40 ± 10° adduction and 30 ± 13° flexion. The lead hip mean peak adduction velocity was 434 ± 83°/s and flexion velocity was 456 ± 156°/s. Simultaneously, the trailing leg hip rapidly extended approaching to a mean peak extension of -8 ± 5° at 39% of the pitch cycle, which is close to passive range of motion constraints. Peak hip abduction of the trailing leg at foot contact was -31 ± 12°, which also approached passive range of motion constraints. Differences and similarities were also noted between the adolescent lower extremity kinematics and adult pitchers; however, a more comprehensive analysis using similar methods is needed for a complete comparison. PMID:22660979

  5. Adolescent baseball pitching technique: lower extremity biomechanical analysis.

    PubMed

    Milewski, Matthew D; Õunpuu, Sylvia; Solomito, Matthew; Westwell, Melany; Nissen, Carl W

    2012-11-01

    Documentation of the lower extremity motion patterns of adolescent pitchers is an important part of understanding the pitching motion and the implication of lower extremity technique on upper extremity loads, injury and performance. The purpose of this study was to take the initial step in this process by documenting the biomechanics of the lower extremities during the pitching cycle in adolescent pitchers and to compare these findings with the published data for older pitchers. Three-dimensional motion analysis using a comprehensive lower extremity model was used to evaluate the fast ball pitch technique in adolescent pitchers. Thirty-two pitchers with a mean age of 12.4 years (range 10.5-14.7 years) and at least 2 years of experience were included in this study. The pitchers showed a mean of 49 ± 12° of knee flexion of the lead leg at foot contact. They tended to maintain this position through ball release, and then extended their knee during the follow through phase (ball release to maximal internal glenohumeral rotation). The lead leg hip rapidly progressed into adduction and flexion during the arm cocking phase with a range of motion of 40 ± 10° adduction and 30 ± 13° flexion. The lead hip mean peak adduction velocity was 434 ± 83°/s and flexion velocity was 456 ± 156°/s. Simultaneously, the trailing leg hip rapidly extended approaching to a mean peak extension of -8 ± 5° at 39% of the pitch cycle, which is close to passive range of motion constraints. Peak hip abduction of the trailing leg at foot contact was -31 ± 12°, which also approached passive range of motion constraints. Differences and similarities were also noted between the adolescent lower extremity kinematics and adult pitchers; however, a more comprehensive analysis using similar methods is needed for a complete comparison.

  6. Importance of Corneal Thickness

    MedlinePlus

    ... News About Us Donate In This Section The Importance of Corneal Thickness email Send this article to ... is important because it can mask an accurate reading of eye pressure, causing doctors to treat you ...

  7. Importing biological materials.

    PubMed

    Wolf, P

    2001-05-01

    This overview discusses critical issues regarding importing of restricted biological materials along with criteria for handling these materials. Guidelines for importing non-restricted biological materials are also covered. Recommendations are given for packaging biological materials for export, and finally, the necessary steps for obtaining an import permit application are outlined. PMID:18429071

  8. Python import replacement

    SciTech Connect

    2011-10-01

    SmartImport.py is a Python source-code file that implements a replacement for the standard Python module importer. The code is derived from knee.py, a file in the standard Python diestribution , and adds functionality to improve the performance of Python module imports in massively parallel contexts.

  9. SOMs-Based Analysis of WRF Extreme Daily Precipitation in Alaska

    NASA Astrophysics Data System (ADS)

    Glisan, J. M.

    2015-12-01

    We analyze daily extremes of precipitation produced with a polar-optimized version of the Advanced Weather Research and Forecasting (ARW-WRF) model that simulated 19 years on the domain developed for the Regional Arctic System (RASM) model. Analysis focuses on Alaska, because of its proximity to the Pacific and Arctic oceans, both of which provide a large moisture fetch inland. Alaska's topography also has an important impact on orographically-forced precipitation. In order to understand the circulation characteristics conducive for extreme precipitation events, we use Self-Organizing Maps (SOMs) to find general patterns of circulation behavior. The SOM algorithm employs an artificial neural network that uses an unsupervised training process. In our analysis, we use mean sea level pressure (MSLP) anomalies to train the SOM. We examine daily widespread extreme precipitation events, defined as at least 25 grid points experiencing 99th percentile precipitation. Using the SOM procedure, we map days with widespread extremes onto the SOM's array of circulation patterns. This mapping aids in determining which nodes are being accessed at higher frequencies, and hence, which circulations are more conducive to extreme events. We show that there are multiple circulation patterns responsible for extreme precipitation differentiated by where they produce extreme events in our analysis region. Additionally, we plot composites of several meteorological fields for SOM nodes being accessed by both extreme and non-extreme events to determine what specific conditions are necessary for a widespread extreme event. Composites of individual nodes (or of adjacent nodes in SOM space) produce more physically reasonable circulations as opposed to composites of all extreme events, which can include multiple synoptic circulation regimes. We also trace the temporal evolution of extreme events through SOM space. Thus, our analysis lays the groundwork for diagnosing differences in atmospheric

  10. Discrete extremal lengths of graph approximations of Sierpinski carpets

    NASA Astrophysics Data System (ADS)

    Malo, Robert Jason

    The study of mathematical objects that are not smooth or regular has grown in importance since Benoit Mandelbrot's foundational work in the in the late 1960s. The geometry of fractals has many of its roots in that work. An important measurement of the size and structure of fractals is their dimension. We discuss various ways to describe a fractal in its canonical form. We are most interested in a concept of dimension introduced by Pierre Pansu in 1989, that of the conformal dimension. We focus on an open question: what is the conformal dimension of the Sierpinski carpet? In this work we adapt an algorithm by Oded Schramm to calculate the discrete extremal length in graph approximations of the Sierpinski carpet. We apply a result by Matias Piaggio to relate the extremal length to the Ahlfors-regular conformal dimension. We find strong numeric evidence suggesting both a lower and upper bound for this dimension.

  11. Role of extreme events in vegetation dynamics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extreme climatic events challenge the capacity of vegetation models, including Dynamic Global Vegetation Models, to predict changes in plant species dynamics at local and regional spatial scales and over time periods relevant to ecologists and managers. Extreme climatic events are defined as large,...

  12. Generalized IRT Models for Extreme Response Style

    ERIC Educational Resources Information Center

    Jin, Kuan-Yu; Wang, Wen-Chung

    2014-01-01

    Extreme response style (ERS) is a systematic tendency for a person to endorse extreme options (e.g., strongly disagree, strongly agree) on Likert-type or rating-scale items. In this study, we develop a new class of item response theory (IRT) models to account for ERS so that the target latent trait is free from the response style and the tendency…

  13. Complex Plasma Research Under Extreme Conditions

    SciTech Connect

    Ishihara, Osamu

    2008-09-07

    Complex plasma research under extreme conditions is described. The extreme conditions include low-dimensionality for self-organized structures of dust particles, dust magnetization in high magnetic field, criticality in phase transition, and cryogenic environment for Coulomb crystals and dust dynamics.

  14. Surface atmospheric extremes (Launch and transportation areas)

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The effects of extreme values of surface and low altitude atmospheric parameters on space vehicle design, tests, and operations are discussed. Atmospheric extremes from the surface to 150 meters for geographic locations of interest to NASA are given. Thermal parameters (temperature and solar radiation), humidity, pressure, and atmospheric electricity (lighting and static) are presented. Weather charts and tables are included.

  15. The Nature and Characteristics of Youthful Extremism

    ERIC Educational Resources Information Center

    Zubok, Iu. A.; Chuprov, V. I.

    2010-01-01

    Extremism is an acute problem of the present day. Moods of extremism are manifested in all spheres of the life and activities of young people--in education, work, business, political life, and leisure activity. They can be found in both individual and group social self-determination and are influenced by the immediate social environment as well as…

  16. EPE The Extreme Physics Explorer

    NASA Technical Reports Server (NTRS)

    Garcia, Michael; Elvis, Martin; Bookbinder, Jay; Brenneman, Laura; Bulbul, Esra; Nulsen, Paul; Patnaude, Dan; Smith, Randall; Bandler, Simon; Okajima, Takashi; Ptak, Andy; Figueroa-Feliciano, Enectali; Chakrabarty, Deepto; Danner, Rolf; Daily, Dean; Fraser, George; Willingale, Richard; Miller, Jon; Turner, T. J.; Risalti, Guido; Galeazzi, Massimiliano

    2012-01-01

    The Extreme Physics Explorer (EPE) is a mission concept that will address fundamental and timely questions in astrophysics which are primary science objectives of IXO. The reach of EPE to the areas outlined in NASA RFI NNH11ZDA018L is shown as a table. The dark green indicates areas in which EPE can do the basic IXO science, and the light green areas where EPE can contribute but will not reach the full IXO capability. To address these science questions, EPE will trace orbits close to the event horizon of black holes, measure black hole spin in active galactic nuclei (AGN), use spectroscopy to characterize outflows and the environment of AGN, map bulk motions and turbulence in galaxy clusters, and observe the process of cosmic feedback where black holes inject energy on galactic and intergalactic scales. EPE gives up the high resolution imaging of IXO in return for lightweight, high TRL foil mirrors which will provide >20 times the effective area of ASTRO-H and similar spatial resolution, with a beam sufficient to study point sources and nearby galaxies and clusters. Advances in micro-calorimeters allow improved performance at high rates with twice the energy resolution of ASTRO-H. A lower TRL option would provide 200 times the area of ASTRO-H using a micro-channel plate optic (MCPO) and a deployable optical bench. Both options are in the middle range of RFI missions at between $600M and $1000M. The EPE foil optic has direct heritage to ASTRO-H, allowing robust cost estimates. The spacecraft is entirely off the shelf and introduces no difficult requirements. The mission could be started and launched in this decade to an L2 orbit, with a three-year lifetime and consumables for 5 years. While ASTRO-H will give us the first taste of high-resolution, non-dispersive X-ray spectroscopy, it will be limited to small numbers of objects in many categories. EPE will give us the first statistically significant samples in each of these categories.

  17. Contrasting responses of mean and extreme snowfall to climate change.

    PubMed

    O'Gorman, Paul A

    2014-08-28

    Snowfall is an important element of the climate system, and one that is expected to change in a warming climate. Both mean snowfall and the intensity distribution of snowfall are important, with heavy snowfall events having particularly large economic and human impacts. Simulations with climate models indicate that annual mean snowfall declines with warming in most regions but increases in regions with very low surface temperatures. The response of heavy snowfall events to a changing climate, however, is unclear. Here I show that in simulations with climate models under a scenario of high emissions of greenhouse gases, by the late twenty-first century there are smaller fractional changes in the intensities of daily snowfall extremes than in mean snowfall over many Northern Hemisphere land regions. For example, for monthly climatological temperatures just below freezing and surface elevations below 1,000 metres, the 99.99th percentile of daily snowfall decreases by 8% in the multimodel median, compared to a 65% reduction in mean snowfall. Both mean and extreme snowfall must decrease for a sufficiently large warming, but the climatological temperature above which snowfall extremes decrease with warming in the simulations is as high as -9 °C, compared to -14 °C for mean snowfall. These results are supported by a physically based theory that is consistent with the observed rain-snow transition. According to the theory, snowfall extremes occur near an optimal temperature that is insensitive to climate warming, and this results in smaller fractional changes for higher percentiles of daily snowfall. The simulated changes in snowfall that I find would influence surface snow and its hazards; these changes also suggest that it may be difficult to detect a regional climate-change signal in snowfall extremes.

  18. Cardiovascular flow simulation at extreme scale

    NASA Astrophysics Data System (ADS)

    Zhou, Min; Sahni, Onkar; Kim, H. Jin; Figueroa, C. Alberto; Taylor, Charles A.; Shephard, Mark S.; Jansen, Kenneth E.

    2009-12-01

    As cardiovascular models grow more sophisticated in terms of the geometry considered, and more physiologically realistic boundary conditions are applied, and fluid flow is coupled to structural models, the computational complexity grows. Massively parallel adaptivity and flow solvers with extreme scalability enable cardiovascular simulations to reach an extreme scale while keeping the time-to-solution reasonable. In this paper, we discuss our efforts in this area and provide two demonstrations: one on an extremely large and complex geometry (including many of the major arteries below the neck) where the solution is efficiently captured with anisotropic adaptivity and another case (severe abdominal aorta aneurysm) where the transitional flow leads to extremely large meshes (O(109)) and scalability to extremely large core counts (O(105)) for both rigid and deforming wall simulations.

  19. Development of narrow gap welding technology for extremely thick steel

    NASA Astrophysics Data System (ADS)

    Imai, K.; Saito, T.; Okumura, M.

    In the field of extremely thick steel, various narrow gap welding methods were developed on the basis of former welding methods and are used in practice. It is important to develop and improve automatic narrow gap welding, J edge preparation by gas cutting, the prevention of welding defects, wires for narrow gap welding and so on in order to expand the scope of application of the method. Narrow gap welding technologies are described, based on new concepts developed by Nippon Steel Corporation.

  20. Colors of Extreme Exo-Earth Environments

    NASA Astrophysics Data System (ADS)

    Hegde, Siddharth; Kaltenegger, Lisa

    2013-07-01

    The search for extrasolar planets has already detected rocky planets and several planetary candidates with minimum masses that are consistent with rocky planets in the habitable zone of their host stars. A low-resolution spectrum in the form of a color-color diagram of an exoplanet is likely to be one of the first post-detection quantities to be measured for the case of direct detection. In this poster, we explore potentially detectable surface features on rocky exoplanets and their connection to, and importance as, a habitat for extremophiles, as known on Earth. Extremophiles provide us with the minimum known envelope of environmental limits for life on our planet. The color of a planet reveals information on its properties, especially for surface features of rocky planets with clear atmospheres. We use filter photometry in the visible as a first step in the characterization of rocky exoplanets to prioritize targets for follow-up spectroscopy. Many surface environments on Earth have characteristic albedos and occupy a different color space in the visible waveband (0.4-0.9 microns) that can be distinguished remotely. These detectable surface features can be linked to the extreme niches that support extremophiles on Earth and provide a link between geomicrobiology and observational astronomy. This poster explores how filter photometry can serve as a first step in characterizing Earth-like exoplanets for an aerobic as well as an anaerobic atmosphere, thereby prioritizing targets to search for atmospheric biosignatures.

  1. Reverberation noise modeling using extreme value theory

    NASA Astrophysics Data System (ADS)

    La Cour, Brian; Luter, Robert

    2002-05-01

    Normalized matched filter output forms the basis of target detection in active sonar. In a target-free environment, the central theorem, if valid, predicts that the statistics of the envelope follow a Rayleigh distribution, and, to first approximation, this is indeed observed. However, well-known departures from the Rayleigh model are found in the tail end of observed distributions. Traditional approaches to this problem have focused on constructing a simple, parameterized, non-Rayleigh distribution which more closely models observations. This paper suggests a novel alternative which focuses on a robust method of modeling only the tails of the distribution in favor of the less important body. Results from extreme-value theory are used to fit a generalized Pareto distribution (GPD) to the empirical cumulative distribution function, conditioned on a large threshold value. [A random variable X has a GPD if P(X<=x)=1-(1+γx/σ)-1/γ for x>=0, σ>0, and γ real; γ=0 is the exponential distribution.] Estimates of γ and σ are discussed for a broad range of active sonar data, and the results are compared with fits to other popular non-Rayleigh models. The origins of non-Rayleighness are also considered, including finite-size effects, spatial and temporal correlations, and nonuniformity.

  2. Extreme winds and tornadoes: an overview

    SciTech Connect

    McDonald, J.R.

    1985-01-01

    The objective of this course on extreme winds, hurricanes and tornadoes is to provide an overview of these natural phenomenon from the perspective of design of new buildings and structures or the evaluation of existing ones. Information is directly applicable to design and evaluation processes. The premise is that the facility under consideration, which may consist of various buildings, structures, processing equipment, stacks, ventilation ducts, etc., can be classified into certain categories, depending on the importance of the mission performed in the facility or the hazard that is presented by the particular operation. Having classified the facility into an appropriate category will automatically define certain design goals for the facility. The design goals are then met by selecting a design wind speed that is appropriate for the specified exceedance probability and by following certain specified design procedures. The problem then is to determine appropriate wind loads and other applicable loads, including dead loads, live loads, seismic loads and other loads that may act on the structures. The design process can then proceed in the usual manner. In the case of existing facilities the strengths of the various structural elements, subsystems and systems are evaluated and these strengths are related to wind speeds that would result in failure to meet the design goals. 12 refs.

  3. Extreme low temperature tolerance in woody plants.

    PubMed

    Strimbeck, G Richard; Schaberg, Paul G; Fossdal, Carl G; Schröder, Wolfgang P; Kjellsen, Trygve D

    2015-01-01

    Woody plants in boreal to arctic environments and high mountains survive prolonged exposure to temperatures below -40°C and minimum temperatures below -60°C, and laboratory tests show that many of these species can also survive immersion in liquid nitrogen at -196°C. Studies of biochemical changes that occur during acclimation, including recent proteomic and metabolomic studies, have identified changes in carbohydrate and compatible solute concentrations, membrane lipid composition, and proteins, notably dehydrins, that may have important roles in survival at extreme low temperature (ELT). Consideration of the biophysical mechanisms of membrane stress and strain lead to the following hypotheses for cellular and molecular mechanisms of survival at ELT: (1) Changes in lipid composition stabilize membranes at temperatures above the lipid phase transition temperature (-20 to -30°C), preventing phase changes that result in irreversible injury. (2) High concentrations of oligosaccharides promote vitrification or high viscosity in the cytoplasm in freeze-dehydrated cells, which would prevent deleterious interactions between membranes. (3) Dehydrins bind membranes and further promote vitrification or act stearically to prevent membrane-membrane interactions. PMID:26539202

  4. Colors of extreme exo-Earth environments.

    PubMed

    Hegde, Siddharth; Kaltenegger, Lisa

    2013-01-01

    The search for extrasolar planets has already detected rocky planets and several planetary candidates with minimum masses that are consistent with rocky planets in the habitable zone of their host stars. A low-resolution spectrum in the form of a color-color diagram of an exoplanet is likely to be one of the first post-detection quantities to be measured for the case of direct detection. In this paper, we explore potentially detectable surface features on rocky exoplanets and their connection to, and importance as, a habitat for extremophiles, as known on Earth. Extremophiles provide us with the minimum known envelope of environmental limits for life on our planet. The color of a planet reveals information on its properties, especially for surface features of rocky planets with clear atmospheres. We use filter photometry in the visible as a first step in the characterization of rocky exoplanets to prioritize targets for follow-up spectroscopy. Many surface environments on Earth have characteristic albedos and occupy a different color space in the visible waveband (0.4-0.9 μm) that can be distinguished remotely. These detectable surface features can be linked to the extreme niches that support extremophiles on Earth and provide a link between geomicrobiology and observational astronomy. This paper explores how filter photometry can serve as a first step in characterizing Earth-like exoplanets for an aerobic as well as an anaerobic atmosphere, thereby prioritizing targets to search for atmospheric biosignatures.

  5. Colors of extreme exo-Earth environments.

    PubMed

    Hegde, Siddharth; Kaltenegger, Lisa

    2013-01-01

    The search for extrasolar planets has already detected rocky planets and several planetary candidates with minimum masses that are consistent with rocky planets in the habitable zone of their host stars. A low-resolution spectrum in the form of a color-color diagram of an exoplanet is likely to be one of the first post-detection quantities to be measured for the case of direct detection. In this paper, we explore potentially detectable surface features on rocky exoplanets and their connection to, and importance as, a habitat for extremophiles, as known on Earth. Extremophiles provide us with the minimum known envelope of environmental limits for life on our planet. The color of a planet reveals information on its properties, especially for surface features of rocky planets with clear atmospheres. We use filter photometry in the visible as a first step in the characterization of rocky exoplanets to prioritize targets for follow-up spectroscopy. Many surface environments on Earth have characteristic albedos and occupy a different color space in the visible waveband (0.4-0.9 μm) that can be distinguished remotely. These detectable surface features can be linked to the extreme niches that support extremophiles on Earth and provide a link between geomicrobiology and observational astronomy. This paper explores how filter photometry can serve as a first step in characterizing Earth-like exoplanets for an aerobic as well as an anaerobic atmosphere, thereby prioritizing targets to search for atmospheric biosignatures. PMID:23252379

  6. Extreme low temperature tolerance in woody plants

    PubMed Central

    Strimbeck, G. Richard; Schaberg, Paul G.; Fossdal, Carl G.; Schröder, Wolfgang P.; Kjellsen, Trygve D.

    2015-01-01

    Woody plants in boreal to arctic environments and high mountains survive prolonged exposure to temperatures below -40°C and minimum temperatures below -60°C, and laboratory tests show that many of these species can also survive immersion in liquid nitrogen at -196°C. Studies of biochemical changes that occur during acclimation, including recent proteomic and metabolomic studies, have identified changes in carbohydrate and compatible solute concentrations, membrane lipid composition, and proteins, notably dehydrins, that may have important roles in survival at extreme low temperature (ELT). Consideration of the biophysical mechanisms of membrane stress and strain lead to the following hypotheses for cellular and molecular mechanisms of survival at ELT: (1) Changes in lipid composition stabilize membranes at temperatures above the lipid phase transition temperature (-20 to -30°C), preventing phase changes that result in irreversible injury. (2) High concentrations of oligosaccharides promote vitrification or high viscosity in the cytoplasm in freeze-dehydrated cells, which would prevent deleterious interactions between membranes. (3) Dehydrins bind membranes and further promote vitrification or act stearically to prevent membrane–membrane interactions. PMID:26539202

  7. Magnetic Reconnection in Extreme Astrophysical Environments

    NASA Astrophysics Data System (ADS)

    Uzdensky, Dmitri

    Magnetic reconnection is a fundamental plasma physics process of breaking ideal-MHD's frozen-in constraints on magnetic field connectivity and of dramatic rearranging of the magnetic topol-ogy, which often leads to a violent release of the free magnetic energy. Reconnection has long been acknowledged to be of great importance in laboratory plasma physics (magnetic fusion) and in space and solar physics (responsible for solar flares and magnetospheric substorms). In addition, its importance in Astrophysics has been increasingly recognized in recent years. However, due to a great diversity of astrophysical environments, the fundamental physics of astrophysical magnetic reconnection can be quite different from that of the traditional recon-nection encountered in the solar system. In particular, environments like the solar corona and the magnetosphere are characterized by relatively low energy densities, where the plasma is ad-equately described as a mixture of electrons and ions whose numbers are conserved and where the dissipated magnetic energy basically stays with the plasma. In contrast, in many high-energy astrophysical phenomena the energy density is so large that photons play as important a role as electrons and ions and, in particular, radiation pressure and radiative cooling become dominant. In this talk I focus on the most extreme case of high-energy-density astrophysical reconnec-tion — reconnection of magnetar-strength (1014 - 1015 Gauss) magnetic fields, important for giant flares in soft-gamma repeaters (SGRs), and for rapid magnetic energy release in either the central engines or in the relativistic jets of Gamma Ray Bursts (GRBs). I outline the key relevant physical processes and present a new theoretical picture of magnetic reconnection in these environments. The corresponding magnetic energy density is so enormous that, when suddenly released, it inevitably heats the plasma to relativistic temperatures, resulting in co-pious production of electron

  8. Synoptic and meteorological drivers of extreme ozone concentrations over Europe

    NASA Astrophysics Data System (ADS)

    Otero, N.; Sillmann, J.; Schnell, J. L.; Rust, H. W.; Butler, T.

    2016-02-01

    The present work assesses the relationship between local and synoptic meteorological conditions and surface ozone concentration over Europe in spring and summer months, during the period 1998-2012 using a new interpolated data set of observed surface ozone concentrations over the European domain. Along with local meteorological conditions, the influence of large-scale atmospheric circulation on surface ozone is addressed through a set of airflow indices computed with a novel implementation of a grid-by-grid weather type classification across Europe. Drivers of surface ozone over the full distribution of maximum daily 8 h average values are investigated, along with drivers of the extreme high percentiles and exceedances or air quality guideline thresholds. Three different regression techniques are applied: multiple linear regression to assess the drivers of maximum daily ozone, logistic regression to assess the probability of threshold exceedances and quantile regression to estimate the meteorological influence on extreme values, as represented by the 95th percentile. The relative importance of the input parameters (predictors) is assessed by a backward stepwise regression procedure that allows the identification of the most important predictors in each model. Spatial patterns of model performance exhibit distinct variations between regions. The inclusion of the ozone persistence is particularly relevant over southern Europe. In general, the best model performance is found over central Europe, where the maximum temperature plays an important role as a driver of maximum daily ozone as well as its extreme values, especially during warmer months.

  9. Synoptic and meteorological drivers of extreme ozone concentrations over Europe

    NASA Astrophysics Data System (ADS)

    Otero, Noelia Felipe; Sillmann, Jana; Schnell, Jordan L.; Rust, Henning W.; Butler, Tim

    2016-04-01

    The present work assesses the relationship between local and synoptic meteorological conditions and surface ozone concentration over Europe in spring and summer months, during the period 1998-2012 using a new interpolated data set of observed surface ozone concentrations over the European domain. Along with local meteorological conditions, the influence of large-scale atmospheric circulation on surface ozone is addressed through a set of airflow indices computed with a novel implementation of a grid-by-grid weather type classification across Europe. Drivers of surface ozone over the full distribution of maximum daily 8-hour average values are investigated, along with drivers of the extreme high percentiles and exceedances or air quality guideline thresholds. Three different regression techniques are applied: multiple linear regression to assess the drivers of maximum daily ozone, logistic regression to assess the probability of threshold exceedances and quantile regression to estimate the meteorological influence on extreme values, as represented by the 95th percentile. The relative importance of the input parameters (predictors) is assessed by a backward stepwise regression procedure that allows the identification of the most important predictors in each model. Spatial patterns of model performance exhibit distinct variations between regions. The inclusion of the ozone persistence is particularly relevant over Southern Europe. In general, the best model performance is found over Central Europe, where the maximum temperature plays an important role as a driver of maximum daily ozone as well as its extreme values, especially during warmer months.

  10. Limitations of Extreme Nonlinear Ultrafast Nanophotonics

    NASA Astrophysics Data System (ADS)

    Kern, Christian; Zürch, Michael; Spielmann, Christian

    2015-01-01

    High-harmonic generation (HHG) has been established as an indispensable tool in optical spectroscopy. This effect arises for instance upon illumination of a noble gas with sub-picosecond laser pulses at focussed intensities significantly greater than 1012W/cm2. HHG provides a coherent light source in the extreme ultraviolet (XUV) spectral region, which is of importance in inner shell photo ionization of many atoms and molecules. Additionally, it intrinsically features light fields with unique temporal properties. Even in its simplest realization, XUV bursts of sub-femtosecond pulse lengths are released. More sophisticated schemes open the path to attosecond physics by offering single pulses of less than 100 attoseconds duration. Resonant optical antennas are important tools for coupling and enhancing electromagnetic fields on scales below their free-space wavelength. In a special application, placing field-enhancing plasmonic nano antennas at the interaction site of an HHG experiment has been claimed to boost local laser field strengths, from insufficient initial intensities to sufficient values. This was achieved with the use of arrays of bow-tie-shaped antennas of ˜ 100nm in length. However, the feasibility of this concept depends on the vulnerability of these nano-antennas to the still intense driving laser light.We show, by looking at a set of exemplary metallic structures, that the threshold fluence Fth of laser-induced damage (LID) is a greatly limiting factor for the proposed and tested schemes along these lines.We present our findings in the context of work done by other groups, giving an assessment of the feasibility and effectiveness of the proposed scheme.

  11. Astrobiological studies with extremely halophilic Archaea

    NASA Astrophysics Data System (ADS)

    Fendrihan, S.; Lotter, H. Stan

    2007-08-01

    Extremely halophilic Archaea were isolated and characterized by both classical and modern molecular biological methods from hypersaline and haloalkaline lakes, salted soils, solar salterns and rock salt deposits (1). The survival of these micro-organisms after embedding in laboratory-made halite was investigated. Their presence in fluid inclusions was demonstrated by staining with the BacLight LIVE/DEAD kit and observation of their fluorescence by microscopy. Following resuspension of cells from halite crystals, a survival of about 0.5 - 4% according to colony forming units was obtained. In previous studies which focussed on the resistance of halophilic archaea to UV radiation or the space environment, survival of a dose of 110 J/m2 (using liquid cultures) and up to 10 000 J/m2 at a range of 200 - 400 nm was reported, when dried Haloarcula sp. in a single layer were exposed on the Biopan facility (2). We exposed a few haloarchaeal strains to a Martian UV simulator lamp with a range of 200 - 400 nm and an intensity of 41.2 W/m2, obtaining a viability of about 51- 67% of cells following different exposure times. Other studies focus on the detection of haloarchaea in halite by Raman microspectroscopy and by NIR-FT-Raman spectroscopy, which are considered to be important future tools for Mars exploration (3). Using the Dilor XY Raman spectrometer with laser excitation at 514.5 nm, equipped with a confocal microscope BX40 (Olympus Corp., Japan) and a Bruker IFS 66 + FRA106 with laser excitation at 1064 nm (Bruker, Germany), instruments, we obtained characteristic carotenoid peaks contained by these microorganisms. 1. Fendrihan S., Legat A., Pfaffenhuemer M., Gruber C., Weidler G., Gerbl F. Stan Lotter H. (2006) Extremely halophilic archaea and the issue of long-term microbial survival. Review. Environ. Sci. Biotechnol. 5: 203-218. 2. Mancinelli R. L., White M. R., Rothschild L. J. (1998) Biopan survival I : exposure of the osmophiles Synechococcus sp. (Nägeli) and

  12. Detection of trends in precipitation extremes in Zhejiang, east China

    NASA Astrophysics Data System (ADS)

    Tian, Ye; Xu, Yue-Ping; Booij, M. J.; Lin, Shengji; Zhang, Qingqing; Lou, Zhanghua

    2012-01-01

    Extreme weather exerts a huge impact on human beings and it is of vital importance to study the regular pattern of meteorological and hydrological factors. In this paper, a selection of seven extreme indices is used to analyze the trend of precipitation extremes of 18 meteorological stations located in Zhejiang Province, east China using the Mann-Kendall test. Then the precipitation trends in the plum season (from May to July) and typhoon season (from August to October) are studied separately. The results show that the precipitation trend varies from east to west. There is a positive trend in the east and a negative one in the west. The largest part of Zhejiang Province shows a positive trend in heavy precipitation and the most significant upward trend is detected in Dinghai with 3.4 mm/year for precipitation on very wet days. Although the upward trend of extreme precipitation is not prevailing, the range of increase in specific areas is apparent, like Dinghai with 1.3 mm/year. Precipitation intensity exhibits an upward trend in most areas and a typical upward trend can be found in Dachendao, Tianmushan, and Yuhuan with 0.04, 0.02, and 0.05 mm/year respectively. Precipitation intensity in both plum and typhoon seasons has increased too, especially for the coastal stations.

  13. Nonlinear processes reinforce extreme Indian Ocean Dipole events.

    PubMed

    Ng, Benjamin; Cai, Wenju; Walsh, Kevin; Santoso, Agus

    2015-06-26

    Under global warming, climate models show an almost three-fold increase in extreme positive Indian Ocean Dipole (pIOD) events by 2100. These extreme pIODs are characterised by a westward extension of cold sea surface temperature anomalies (SSTAs) which push the downstream atmospheric convergence further west. This induces severe drought and flooding in the surrounding countries, but the processes involved in this projected increase have not been fully examined. Here we conduct a detailed heat budget analysis of 19 models from phase 5 of the Coupled Model Intercomparison Project and show that nonlinear zonal and vertical heat advection are important for reinforcing extreme pIODs. Under greenhouse warming, these nonlinear processes do not change significantly in amplitude, but the frequency of occurrences surpassing a threshold increases. This is due to the projected weakening of the Walker circulation, which leads to the western tropical Indian Ocean warming faster than the east. As such, the magnitude of SSTAs required to shift convection westward is relatively smaller, allowing these convection shifts to occur more frequently in the future. The associated changes in wind and ocean current anomalies support the zonal and vertical advection terms in a positive feedback process and consequently, moderate pIODs become more extreme-like.

  14. Regional frequency analysis of extreme precipitation for Sicily (Italy)

    NASA Astrophysics Data System (ADS)

    Forestieri, Angelo; Blenkinsop, Stephen; Fowler, Hayley; Lo Conti, Francesco; Noto, Leonardo

    2016-04-01

    The analysis of extreme precipitation has always been included among most relevant hydrological applications because of the several important activities linked to the availability of tools for the estimation of extreme rainfall quantiles. These activities include the design of hydraulic civil structures and the evaluation and management of hydraulic and hydrological risk. In this study a frequency analysis of annual maxima precipitation measurements has been carried out for the area of Sicily (Italy). A typical hierarchical regional approach has been adopted for the parameter estimation procedure based on the L-moments method. The identification of homogeneous regions within the procedure has been pursued with a data driven procedure constituted by a principal component analysis of an ensemble of selected auxiliary variables, and a K-means cluster analysis algorithm. Auxiliary variables comprise meteo-climatic information and a representation of the average seasonal distribution of intense events. Results have been evaluated by means of a Monte Carlo experiment based on the comparison between at-site and regional fitted frequency distributions. Moreover, results have been compared with previous analyses performed for the same area. The study provides an updated tool for the modelling of extreme precipitation for the area of Sicily (Italy), with different features respect to previous tools both in terms of definition of homogeneous zones and in terms of parameters of the frequency distribution. Meteo-climatic information and the seasonality of extreme events retrieved from the dataset has been proficuously exploited in the analysis.

  15. Geophysical Hazards and Preventive Disaster Management of Extreme Natural Events

    NASA Astrophysics Data System (ADS)

    Ismail-Zadeh, A.; Takeuchi, K.

    2007-12-01

    Geophysical hazard is potentially damaging natural event and/or phenomenon, which may cause the loss of life or injury, property damage, social and economic disruption, or environmental degradation. Extreme natural hazards are a key manifestation of the complex hierarchical nonlinear Earth system. An understanding, accurate modeling and forecasting of the extreme hazards are most important scientific challenges. Several recent extreme natural events (e.g., 2004 Great Indian Ocean Earthquake and Tsunami and the 2005 violent Katrina hurricane) demonstrated strong coupling between solid Earth and ocean, and ocean and atmosphere. These events resulted in great humanitarian tragedies because of a weak preventive disaster management. The less often natural events occur (and the extreme events are rare by definition), the more often the disaster managers postpone the preparedness to the events. The tendency to reduce the funding for preventive disaster management of natural catastrophes is seldom follows the rules of responsible stewardship for future generations neither in developing countries nor in highly developed economies where it must be considered next to malfeasance. Protecting human life and property against earthquake disasters requires an uninterrupted chain of tasks: from (i) understanding of physics of the events, analysis and monitoring, through (ii) interpretation, modeling, hazard assessment, and prediction, to (iii) public awareness, preparedness, and preventive disaster management.

  16. Climate extremes in Malaysia and the equatorial South China Sea

    NASA Astrophysics Data System (ADS)

    Salahuddin, Ahmed; Curtis, Scott

    2011-08-01

    The southern extent of the South China Sea (SCS) is an important natural resource epicenter for Malaysia which experiences climate extremes. This paper documents the variability of extremes in the equatorial SCS through selected ground-based observations of precipitation in Malaysia and ship-based observations of wind data in the Maritime Continent region, to elucidate the interrelationship between precipitation variability over Malaysia and wind variability over the ocean. The data have been carefully inspected and analyzed, and related to the real-time multivariate Madden-Julian Oscillation (MJO) time series. The analysis suggests that the northeast or boreal winter monsoon dominates extreme rainfall in eastern Malaysian cities. Further, the west coast of Peninsular Malaysia and Borneo Malaysia are affected by the MJO differently than the east coast of Peninsular Malaysia. From the wind analysis we found that average zonal wind is westerly from May to September and easterly from November to April. When the active (convective) phase of the MJO is centered over the Maritime Continent, the strong westerly wind bursts are more frequent in the South China Sea. While more investigation is needed, these results suggest that the status of the Madden-Julian Oscillation can be used to help forecast climate extremes in areas of Malaysia.

  17. Nonlinear processes reinforce extreme Indian Ocean Dipole events

    PubMed Central

    Ng, Benjamin; Cai, Wenju; Walsh, Kevin; Santoso, Agus

    2015-01-01

    Under global warming, climate models show an almost three-fold increase in extreme positive Indian Ocean Dipole (pIOD) events by 2100. These extreme pIODs are characterised by a westward extension of cold sea surface temperature anomalies (SSTAs) which push the downstream atmospheric convergence further west. This induces severe drought and flooding in the surrounding countries, but the processes involved in this projected increase have not been fully examined. Here we conduct a detailed heat budget analysis of 19 models from phase 5 of the Coupled Model Intercomparison Project and show that nonlinear zonal and vertical heat advection are important for reinforcing extreme pIODs. Under greenhouse warming, these nonlinear processes do not change significantly in amplitude, but the frequency of occurrences surpassing a threshold increases. This is due to the projected weakening of the Walker circulation, which leads to the western tropical Indian Ocean warming faster than the east. As such, the magnitude of SSTAs required to shift convection westward is relatively smaller, allowing these convection shifts to occur more frequently in the future. The associated changes in wind and ocean current anomalies support the zonal and vertical advection terms in a positive feedback process and consequently, moderate pIODs become more extreme-like. PMID:26114441

  18. Nonlinear processes reinforce extreme Indian Ocean Dipole events

    NASA Astrophysics Data System (ADS)

    Ng, Benjamin; Cai, Wenju; Walsh, Kevin; Santoso, Agus

    2015-06-01

    Under global warming, climate models show an almost three-fold increase in extreme positive Indian Ocean Dipole (pIOD) events by 2100. These extreme pIODs are characterised by a westward extension of cold sea surface temperature anomalies (SSTAs) which push the downstream atmospheric convergence further west. This induces severe drought and flooding in the surrounding countries, but the processes involved in this projected increase have not been fully examined. Here we conduct a detailed heat budget analysis of 19 models from phase 5 of the Coupled Model Intercomparison Project and show that nonlinear zonal and vertical heat advection are important for reinforcing extreme pIODs. Under greenhouse warming, these nonlinear processes do not change significantly in amplitude, but the frequency of occurrences surpassing a threshold increases. This is due to the projected weakening of the Walker circulation, which leads to the western tropical Indian Ocean warming faster than the east. As such, the magnitude of SSTAs required to shift convection westward is relatively smaller, allowing these convection shifts to occur more frequently in the future. The associated changes in wind and ocean current anomalies support the zonal and vertical advection terms in a positive feedback process and consequently, moderate pIODs become more extreme-like.

  19. Acquired dermal melanocytosis of the face and extremities.

    PubMed

    Ouchi, T; Ishii, K; Nishikawa, T; Ishiko, A

    2016-08-01

    Acquired dermal melanocytosis (ADM) is a relatively rare, but well-described disease among adolescent to middle-aged East Asian women, particularly those of Japanese and Chinese descent. Clinically, ADM manifests as multiple punctate and greyish-brown pigmented areas 1-3 mm in diameter occurring on both sides of the forehead and zygomatic region. The subtype of ADM affecting the face and extremities is extremely rare even in East Asian women. We describe three patients with ADM of the face and extremities (ADMFE) and their characteristic clinical features. All patients were Japanese women, and showed multiple greyish-brown pigmentations on both nasal wings and on the extensor surface of the extremities. We found that the clinical features were strikingly uniform, and that a pigmented lesion on the nasal wing can be an important clue to distinguish ADMFE from other hyperpigmented diseases of the hands and feet. One patient was treated with Q-switched ruby laser with excellent outcome. Increased awareness of ADMFE can lead to earlier diagnosis and potential treatment. PMID:27338120

  20. Mekong River flow and hydrological extremes under climate change

    NASA Astrophysics Data System (ADS)

    Phi Hoang, Long; Lauri, Hannu; Kummu, Matti; Koponen, Jorma; van Vliet, Michelle T. H.; Supit, Iwan; Leemans, Rik; Kabat, Pavel; Ludwig, Fulco

    2016-07-01

    Climate change poses critical threats to water-related safety and sustainability in the Mekong River basin. Hydrological impact signals from earlier Coupled Model Intercomparison Project phase 3 (CMIP3)-based assessments, however, are highly uncertain and largely ignore hydrological extremes. This paper provides one of the first hydrological impact assessments using the CMIP5 climate projections. Furthermore, we model and analyse changes in river flow regimes and hydrological extremes (i.e. high-flow and low-flow conditions). In general, the Mekong's hydrological cycle intensifies under future climate change. The scenario's ensemble mean shows increases in both seasonal and annual river discharges (annual change between +5 and +16 %, depending on location). Despite the overall increasing trend, the individual scenarios show differences in the magnitude of discharge changes and, to a lesser extent, contrasting directional changes. The scenario's ensemble, however, shows reduced uncertainties in climate projection and hydrological impacts compared to earlier CMIP3-based assessments. We further found that extremely high-flow events increase in both magnitude and frequency. Extremely low flows, on the other hand, are projected to occur less often under climate change. Higher low flows can help reducing dry season water shortage and controlling salinization in the downstream Mekong Delta. However, higher and more frequent peak discharges will exacerbate flood risks in the basin. Climate-change-induced hydrological changes will have important implications for safety, economic development, and ecosystem dynamics and thus require special attention in climate change adaptation and water management.

  1. New Options for Vascularized Bone Reconstruction in the Upper Extremity

    PubMed Central

    Houdek, Matthew T.; Wagner, Eric R.; Wyles, Cody C.; Nanos, George P.; Moran, Steven L.

    2015-01-01

    Originally described in the 1970s, vascularized bone grafting has become a critical component in the treatment of bony defects and non-unions. Although well established in the lower extremity, recent years have seen many novel techniques described to treat a variety of challenging upper extremity pathologies. Here the authors review the use of different techniques of vascularized bone grafts for the upper extremity bone pathologies. The vascularized fibula remains the gold standard for the treatment of large bone defects of the humerus and forearm, while also playing a role in carpal reconstruction; however, two other important options for larger defects include the vascularized scapula graft and the Capanna technique. Smaller upper extremity bone defects and non-unions can be treated with the medial femoral condyle (MFC) free flap or a vascularized rib transfer. In carpal non-unions, both pedicled distal radius flaps and free MFC flaps are viable options. Finally, in skeletally immature patients, vascularized fibular head epiphyseal transfer can provide growth potential in addition to skeletal reconstruction. PMID:25685100

  2. Changes in Concurrent Precipitation and Temperature Extremes

    DOE PAGESBeta

    Hao, Zengchao; AghaKouchak, Amir; Phillips, Thomas J.

    2013-08-01

    While numerous studies have addressed changes in climate extremes, analyses of concurrence of climate extremes are scarce, and climate change effects on joint extremes are rarely considered. This study assesses the occurrence of joint (concurrent) monthly continental precipitation and temperature extremes in Climate Research Unit (CRU) and University of Delaware (UD) observations, and in 13 Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate simulations. Moreover, the joint occurrences of precipitation and temperature extremes simulated by CMIP5 climate models are compared with those derived from the CRU and UD observations for warm/wet, warm/dry, cold/wet, and cold/dry combinations of joint extremes.more » The number of occurrences of these four combinations during the second half of the 20th century (1951–2004) is assessed on a common global grid. CRU and UD observations show substantial increases in the occurrence of joint warm/dry and warm/wet combinations for the period 1978–2004 relative to 1951–1977. The results show that with respect to the sign of change in the concurrent extremes, the CMIP5 climate model simulations are in reasonable overall agreement with observations. The results reveal notable discrepancies between regional patterns and the magnitude of change in individual climate model simulations relative to the observations of precipitation and temperature.« less

  3. Understanding hydrological extremes in the Anthropocene

    NASA Astrophysics Data System (ADS)

    Mård, Johanna; Di Baldassarre, Giuliano

    2016-04-01

    Hydrological extremes, from floods to droughts, pose one of the greatest challenges of the 21st century. Many of these challenges are associated with societal interactions with water, as people control or impact hydrological systems in a multitude of ways while they are also being affected and shaped by hydrological extremes, depending on their response to drought and flood events. However, the fact that the human and natural components of freshwater systems interact and co-evolve over time is often not taken into account. There is a need to study the two-way coupling between hydrology and society within a more comprehensive framework for hydrological extremes to anticipate future trajectories in a rapidly changing world. We present an interdisciplinary framework (and concepts) to identify internal controlling variables, processes and feedbacks, and the external system drivers and disturbances of the coupled human-water system with regard to hydrological extremes. To achieve this, the study (i) synthesizes existing research on coupled human-water system focusing on floods and droughts, (ii) analyzes hydrological extremes that have already occurred and their spatiotemporal patterns to investigate what patterns are observed in different regions of the world, and (iii) systematically describe the observed hydrological extremes, their causes and the interactions and feedbacks between hydrology and society. Advancing our understanding of mechanisms and feedbacks driving hydrological extremes is essential to better anticipate how the coupled human-water system will respond to future environmental change.

  4. Changes in Concurrent Precipitation and Temperature Extremes

    SciTech Connect

    Hao, Zengchao; AghaKouchak, Amir; Phillips, Thomas J.

    2013-08-01

    While numerous studies have addressed changes in climate extremes, analyses of concurrence of climate extremes are scarce, and climate change effects on joint extremes are rarely considered. This study assesses the occurrence of joint (concurrent) monthly continental precipitation and temperature extremes in Climate Research Unit (CRU) and University of Delaware (UD) observations, and in 13 Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate simulations. Moreover, the joint occurrences of precipitation and temperature extremes simulated by CMIP5 climate models are compared with those derived from the CRU and UD observations for warm/wet, warm/dry, cold/wet, and cold/dry combinations of joint extremes. The number of occurrences of these four combinations during the second half of the 20th century (1951–2004) is assessed on a common global grid. CRU and UD observations show substantial increases in the occurrence of joint warm/dry and warm/wet combinations for the period 1978–2004 relative to 1951–1977. The results show that with respect to the sign of change in the concurrent extremes, the CMIP5 climate model simulations are in reasonable overall agreement with observations. The results reveal notable discrepancies between regional patterns and the magnitude of change in individual climate model simulations relative to the observations of precipitation and temperature.

  5. The Climatology of Climate Extremes in the World's Major Growing Regions

    NASA Astrophysics Data System (ADS)

    Troy, T.; Zhu, X.

    2015-12-01

    A stable food supply is increasingly important as global populations grow and climate variability and extremes affect crop yields. It is therefore critical to quantify the occurrence of extremes in major growing regions globally to understand the vulnerability of the global food supply to climate. First, we grid the GHCN historical climate data and evaluate the effect of gridding on estimation of agriculturally relevant climate extremes, such as heat waves, consecutive dry days, and precipitation intensity. We find that the differences between gridded indices and the raw station indices are small, mostly less than 10%. We then evaluate the climatology of climate extremes and the probability of concurrent extremes, both within one growing region and across multiple regions globally. We find that the correlation of two precipitation or temperature related indices are quite strong, such that the probability of another extreme occurring increases given the occurrence of one extreme. These results provide estimations of the global food supply's vulnerability to climate variability and extremes, which is critical for planning in the coming decades with projections of more frequent and more intense climate extremes.

  6. Emergy and Its Importance

    EPA Science Inventory

    Emergy is an important quantity needed for public policy analysis that is based on a complex methodology. The intent of this Environmental Research Brief is to define emergy and its importance in a manner that is accessible to everyone with at least a high school education. Emer...

  7. Hydroclimatological Aspects of the Extreme 2011 Assiniboine River Basin Flood

    NASA Astrophysics Data System (ADS)

    Brimelow, J.; Szeto, K.; Bonsal, B. R.; Hanesiak, J.; Kochtubajda, B.; Stewart, R. E.

    2014-12-01

    In the spring and early summer of 2011, the Assiniboine River Basin in Canada experienced an extreme flood that was unprecedented in terms of duration and volume of water. The flood had significant socioeconomic impacts and caused over one billion dollars in damage. Contrary to what one might expect for such an extreme flood, individual precipitation events before and during the 2011 flood were not extreme; instead, it was the cumulative impact and timing of precipitation events going back to the summer of 2010 that played a key role in the 2011 flood. The summer and fall of 2010 were exceptionally wet, resulting in soil moisture levels being much above normal at the time of freeze up. This was followed by above-average precipitation during the winter of 2010-2011, and record-breaking basin-averaged snow-water equivalent values in March and April 2011. Abnormally cold temperatures in March delayed the spring melt by about two weeks, with the result that the above-average seasonal melt freshet occurred close to the onset of abnormally heavy rains in May and June. The large-scale atmospheric flow during May and June 2011 favoured increased cyclone activity over the central and northern U.S., which produced an anomalously large number of heavy rainfall events over the basin. All of these factors combined to generate extreme surface runoff and flooding. We used JRA-55 reanalysis data to quantify the relative importance of snowmelt, soil moisture and spring precipitation in contributing to the unprecedented flood and to demonstrate how the 2011 flood was unique compared to previous floods in the basin. Data and research from this study can be used to validate and improve flood forecasting techniques over this important basin; our findings also raise important questions regarding the impact of climate change on basins that experience pluvial and nival flooding.

  8. Extreme Geohazards: Reducing Disaster Risk and Increasing Resilience

    NASA Astrophysics Data System (ADS)

    Plag, Hans-Peter; Stein, Seth; Brocklebank, Sean; Jules-Plag, Shelley; Campus, Paola

    2014-05-01

    damage on a global scale for a globally connected and stressed society. In particular, large volcanic eruptions could impact climate, damage anthropogenic infrastructure and interrupt resource supplies on a global scale. The occurrence of one or more of the largest volcanic eruptions that took place during the last 2,000 years under today's conditions would likely cause global disasters or catastrophes challenging civilization. Integration of these low-probability, high-impact events in DRR requires an approach focused on resilience and antifragility, as well as the ability to cope with, and recover from failure of infrastructures and social systems. Resilience results from social capital even more than from the robustness of infrastructure. While it is important to understand the hazards through the contribution of geosciences, it is equally important to understand through the contribution of social sciences and engineering the societal processes involved with coping with hazards or leading to failure. For comprehensive development of resilience to natural hazards and, in particular, extreme geohazards, synergy between geosciences, engineering and social sciences, jointed to an improved science-policy relationship is key to success. For example, a simple cost-benefit analysis shows that a comprehensive monitoring system that could identify the onset of an extreme volcanic eruption with sufficient lead time to allow for a globally coordinated preparation makes economic sense. The WP recommends implementation of such a monitoring system with global coverage, assesses the existing assets in current monitoring systems, and illustrates many benefits, besides providing early warning for extreme volcanic eruptions. However, such a monitoring system can provide resilience only via the capability of the global community to react to early warnings. The WP recommends achieving this through the establishment of a global coordination platform comparable to IPCC's role in addressing

  9. Extreme Ultraviolet Imaging Telescope (EIT)

    NASA Technical Reports Server (NTRS)

    Lemen, J. R.; Freeland, S. L.

    1997-01-01

    Efforts concentrated on development and implementation of the SolarSoft (SSW) data analysis system. From an EIT analysis perspective, this system was designed to facilitate efficient reuse and conversion of software developed for Yohkoh/SXT and to take advantage of a large existing body of software developed by the SDAC, Yohkoh, and SOHO instrument teams. Another strong motivation for this system was to provide an EIT analysis environment which permits coordinated analysis of EIT data in conjunction with data from important supporting instruments, including Yohkoh/SXT and the other SOHO coronal instruments; CDS, SUMER, and LASCO. In addition, the SSW system will support coordinated EIT/TRACE analysis (by design) when TRACE data is available; TRACE launch is currently planned for March 1998. Working with Jeff Newmark, the Chianti software package (K.P. Dere et al) and UV /EUV data base was fully integrated into the SSW system to facilitate EIT temperature and emission analysis.

  10. Observed and Projected Climate Extremities in Chennai Metropolitan Area

    NASA Astrophysics Data System (ADS)

    Anushiya, j.; Andimuthu, R.

    2013-12-01

    Analyses of observed climate throughout world revealed some significant changes in the extremes. Any change in the frequency or severity of extreme climate events would have profound impacts on the resilience of nature and society. It is thus very important to analyze extreme events to reliably monitor and detect climate change. Chennai is the fourth largest metropolis in India and one of the fastest growing economic and Industrial growth centers in South Asia. Population has grown rapidly in the last 20 years due to its major industrialization and tremendous growth. Already Chennai's day and night time Temperature shows an increasing trend. The past incidence of catastrophic flooding was observed in the city due to heavy rains associated with depressions and cyclonic storm lead floods in major rivers. After 2000, the incidents were reported repeatedly. The effort has made in this study to find the observed climate extremities over the past years and in the future. For observed changes, IMD gridded data set, and station data are used. Future high resolution climate scenarios (0.220x0.220) are developed through RCM using PRECIS. The boundary data have provided by the UK Met office. The selected members are simulated under the A1B scenario (a mid range emission scenario) for a continuous run till 2100. Climate indices listed by Expert Team (ET) on Climate Change Detection and Indices (ETCCDI) by the CLIVAR are considered in this study. The indices were obtained using the software package RClimDex. Kendall's tau based slope estimator has been used to find the significance lavel. The results shows the significant increasing tendency of warm days (TX90P) in the past and in future. The trends in extreme wet days (R99P) are also increased. The growth in population, urban and industrial area, economic activities, depletion of natural resources along with changing climate are forced to develop the infrastructure includes climate friendly policies to adopt and to ensure the

  11. Astronomy and the Extreme Ultraviolet Explorer satellite.

    PubMed

    Bowyer, S

    1994-01-01

    The extreme ultraviolet wave band (100 to 912 angstroms) was thought until recently to be useless to astronomy, primarily because the opacity of the interstellar medium would prevent observations at these wavelengths. However, the interstellar medium has been found to be markedly inhomogeneous in both density and ionization state and the sun is fortunately located in a region of low extreme ultraviolet opacity. The Extreme Ultraviolet Explorer, launched in June 1992, has surveyed the sky in this wave band and has detected a wide variety of astronomical sources at considerable distances, including some extragalactic objects. Studies in the extreme ultraviolet band have already begun to increase our understanding of the contents of the universe.

  12. NASA Measures Extreme Precipitation From Space

    NASA Video Gallery

    From Jan. 25 through Feb. 3, IMERG data estimated that the most extreme precipitation over the United States during this period was over 200mm (7.9 inches) in an area where stormy weather frequentl...

  13. Extremal dynamics and punctuated co-evolution

    NASA Astrophysics Data System (ADS)

    Sneppen, Kim

    1995-02-01

    Extremal dynamics opens up a new way for understanding the coherence that is observed in some large non-equilibrium systems. Extremal dynamics is characterized by quasistatic motion where only one part of the large system is active at a given instant: the part where a local variable assumes a global extremum value. Extremal dynamics may apply when the parts of the system nearly always are caught in metastable states. Examples from physics may include earthquakes, fluid invasion in porous media and possibly also dynamical roughening of interfaces. We discuss a simple model of extremal dynamics and its application to biological macroevolution. The model can be formulated as an ecology of adapting interacting species. The environment of any given species is affected by other species; hence it may change with time. For low mutation rate the model ecology expands at a self-organized critical state where periods of statis alternate with avalanches of evolutionary changes.

  14. Astronomy and the Extreme Ultraviolet Explorer satellite

    NASA Technical Reports Server (NTRS)

    Bowyer, S.

    1994-01-01

    The extreme ultraviolet wave band (100 to 912 angstroms) was thought until recently to be useless to astronomy, primarily because the opacity of the interstellar medium would prevent observations at these wavelengths. However, the interstellar medium has been found to be markedly inhomogeneous in both density and ionization state and the sun is fortunately located in a region of low extreme ultraviolet opacity. The Extreme Ultraviolet Explorer, launched in June 1992, has surveyed the sky in this wave band and has detected a wide variety of astronomical sources at considerable distances, including some extragalactic objects. Studies in the extreme ultraviolet band have already begun to increase our understanding of the contents of the universe.

  15. Importance of Family Routines

    MedlinePlus

    ... Listen Español Text Size Email Print Share The Importance of Family Routines Page Content ​Every family needs ... child to sleep. These rituals can include storytelling, reading aloud, conversation, and songs. Try to avoid exciting ...

  16. Are recent severe floods in Xiang River basin of China linked with the increase extreme precipitation?

    NASA Astrophysics Data System (ADS)

    Cheng, L.; Du, J.

    2015-12-01

    The Xiang River, a main tributary of the Yangtze River, is subjected to high floods frequently in recent twenty years. Climate change, including abrupt shifts and fluctuations in precipitation is an important factor influencing hydrological extreme conditions. In addition, human activities are widely recognized as another reasons leading to high flood risk. With the effects of climate change and human interventions on hydrological cycle, there are several questions that need to be addressed. Are floods in the Xiang River basin getting worse? Whether the extreme streamflow shows an increasing tendency? If so, is it because the extreme rainfall events have predominant effect on floods? To answer these questions, the article detected existing trends in extreme precipitation and discharge using Mann-Kendall test. Continuous wavelet transform method was employed to identify the consistency of changes in extreme precipitation and discharge. The Pearson correlation analysis was applied to investigate how much degree of variations in extreme discharge can be explained by climate change. The results indicate that slightly upward trends can be detected in both extreme rainfalls and discharge in the upper region of Xiang River basin. For the most area of middle and lower river basin, the extreme rainfalls show significant positive trends, but the extreme discharge displays slightly upward trends with no significance at 90% confidence level. Wavelet transform analysis results illustrate that highly similar patterns of signal changes can be seen between extreme precipitation and discharge in upper section of the basin, while the changes in extreme precipitation for the middle and lower reaches do not always coincide with the extreme streamflow. The correlation coefficients of the wavelet transforms for the precipitation and discharge signals in most area of the basin pass the significance test. The conclusion may be drawn that floods in recent years are not getting worse in

  17. Extreme events monitoring from space

    NASA Astrophysics Data System (ADS)

    Kerr, Yann; Bitar, Ahmad Al; Mahmoodi, Ali; Richaume, Philippe; Al-Yaari, Amen; Wigneron, Jean-Pierre

    2016-04-01

    The SMOS (Soil Moisture and Ocean Salinity) satellite was successfully launched in November 2009. This ESA led mission for Earth Observation is dedicated to provide soil moisture over continental surface (with an accuracy goal of 0.04 m3/m3), vegetation water content over land, and ocean salinity. These geophysical features are important as they control the energy balance between the surface and the atmosphere. Their knowledge at a global scale is of interest for climatic and weather researches, and in particular in improving model forecasts. The Soil Moisture and Ocean Salinity mission has now been collecting data for 6 years. The whole data set has just been reprocessed (Version 620 for levels 1 and 2 and version 3 for level 3 CATDS). After 6 years it seems important to start using data for having a look at anomalies and see how they can relate to large scale events The purpose of this communication is to present the mission results after more than six years in orbit in a climatic trend perspective, as through such a period anomalies can be detected. Thereby we benefit from consistent datasets provided through the latest reprocessing using most recent algorithm enhancements. Using the above mentioned products it is possible to follow large events such as the evolution of the droughts in North America, or water fraction evolution over the Amazonian basin. In this occasion we will focus on the analysis of SMOS and ancillary products anomalies to reveal two climatic trends, the temporal evolution of water storage over the Indian continent in relation to rainfall anomalies, and the global impact of El Nino types of events on the general water storage distribution. This presentation shows in detail the use of long term data sets of L-band microwave radiometry in two specific cases, namely droughts and water budget over a large basin. Several other analyses are under way currently. Obviously, vegetation water content, but also dielectric constant, are carrying a wealth

  18. Hierarchical Spatial Analysis of Extreme Precipitation in Urban Areas

    NASA Astrophysics Data System (ADS)

    Rajulapati, C. R.; Mujumdar, P.

    2015-12-01

    Quantification of extreme precipitation is important for hydrologic designs. Due to lack of availability of extreme precipitation data for sufficiently large number of years, estimating the probability of extreme events is difficult and extrapolating the distributions to locations where observations are not available is challenging. In an urban setting, the spatial variation of precipitation can be high; the precipitation amounts and patterns often vary within short distances of less than 10 km. Therefore it is crucial to study the uncertainties in the spatial variation of precipitation in urban areas. In this work, the extreme precipitation is modeled spatially using the Bayesian hierarchical spatial analysis and the spatial variation of return levels is studied. The analysis is carried out with both the Peak over Threshold (PoT) and the Block Maxima approaches for defining the extreme precipitation. The study area is Bangalore city, India. Daily data for seventeen stations in and around Bangalore city are considered in the study. The threshold exceedences are modeled using a Generalized Pareto (GP) distribution and the block maxima are modeled using Generalized Extreme Value (GEV) distribution. In the hierarchical analysis, the statistical model is specified in three layers. The data layer models the data (either block maxima or the threshold exceedences) at each station. In the process layer, the latent spatial process characterized by geographical and climatological covariates (lat-lon, elevation, mean temperature etc.) which drives the extreme precipitation is modeled and in the prior level, the prior distributions that govern the latent process are modeled. Markov Chain Monte Carlo (MCMC) algorithm is used to obtain the samples of parameters from the posterior distribution of parameters. The spatial maps of return levels for specified return periods, along with the associated uncertainties, are obtained. The results show that there is significant variation in

  19. Possible future changes in extreme events over Northern Eurasia

    NASA Astrophysics Data System (ADS)

    Monier, Erwan; Sokolov, Andrei; Scott, Jeffery

    2013-04-01

    In this study, we investigate possible future climate change over Northern Eurasia and its impact on extreme events. Northern Eurasia is a major player in the global carbon budget because of boreal forests and peatlands. Circumpolar boreal forests alone contain more than five times the amount of carbon of temperate forests and almost double the amount of carbon of the world's tropical forests. Furthermore, severe permafrost degradation associated with climate change could result in peatlands releasing large amounts of carbon dioxide and methane. Meanwhile, changes in the frequency and magnitude of extreme events, such as extreme precipitation, heat waves or frost days are likely to have substantial impacts on Northern Eurasia ecosystems. For this reason, it is very important to quantify the possible climate change over Northern Eurasia under different emissions scenarios, while accounting for the uncertainty in the climate response and changes in extreme events. For several decades, the Massachusetts Institute of Technology (MIT) Joint Program on the Science and Policy of Global Change has been investigating uncertainty in climate change using the MIT Integrated Global System Model (IGSM) framework, an integrated assessment model that couples an earth system model of intermediate complexity (with a 2D zonal-mean atmosphere) to a human activity model. In this study, regional change is investigated using the MIT IGSM-CAM framework that links the IGSM to the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM). New modules were developed and implemented in CAM to allow climate parameters to be changed to match those of the IGSM. The simulations presented in this paper were carried out for two emission scenarios, a "business as usual" scenario and a 660 ppm of CO2-equivalent stabilization, which are similar to, respectively, the Representative Concentration Pathways RCP8.5 and RCP4.5 scenarios. Values of climate sensitivity and net aerosol

  20. A Weather climate change Impact Study at Extreme Resolution (WISER)

    NASA Astrophysics Data System (ADS)

    Gadian, A.; Burton, R.; Bruyere, C. L.; Done, J.; Tye, M. R.; Holland, G. J.; Thielen, J.; Blyth, A. M.

    2014-12-01

    Understanding and simulation of weather scale processes is required to understand extremes in the rapidly changing climate. The resolution required to include meso-scale features, is still out of the reach of climate model resolution, and this project attempts to include the important meso-scale features. WISER (Weather climate change Impact Study at Extreme Resolution) is a regional climate study to use a numerical weather model (WRF), in a channel formulation (+/- 68 degrees latitude) at a resolution of 20 km at the equator reducing to 9 km at the Northern and Southern boundaries. The inner domain nested regional model at a resolution of 3-4 km over Western Europe aims at resolving the larger convective scale precipitation events statistically. (see figure for geometrical domain set up). The outer domain is driven by ERA interim climate reanalysis global fields for recent decades 1989-2001; the nested inner domain d02 is driven by the outer domain. The inner model climatological statistics are compared with observations and with those from the outer domain, with particular reference for the statistical convective precipitation extremes. The extremes of the pdfs are shown to be better represented by the increase in resolution and suggest that this could be a tool useful in examining the likely extremes in future climates. The data also provides an assessment of the uncertainty in the precipitation extremes and an alternative approach to ownscaling. The overall aim is to examine statistical changes in(a) general precipitation over western Europe and the UK,(b) in quantity and frequency of severe and hazardous convective rainfall events. The future work-plan is(i) to complete simulations for the decade 1989-2000 driven by ERA-Interim reanalysis data(ii) to complete simulations for the same decade with boundary CESM/CAM climate model data to compute offset and bias corrections(iii) to complete climate scenarios for decadal periods, 2020-2030 initially and later 2050

  1. EXTREME VALUE THEORY WITH OPERATOR NORMING

    PubMed Central

    MEERSCHAERT, MARK M.; SCHEFFLER, HANS-PETER; STOEV, STILIAN A.

    2013-01-01

    A new approach to extreme value theory is presented for vector data with heavy tails. The tail index is allowed to vary with direction, where the directions are not necessarily along the coordinate axes. Basic asymptotic theory is developed, using operator regular variation and extremal integrals. A test is proposed to judge whether the tail index varies with direction in any given data set. PMID:24443640

  2. Test fields cannot destroy extremal black holes

    NASA Astrophysics Data System (ADS)

    Natário, José; Queimada, Leonel; Vicente, Rodrigo

    2016-09-01

    We prove that (possibly charged) test fields satisfying the null energy condition at the event horizon cannot overspin/overcharge extremal Kerr–Newman or Kerr–Newman–anti de Sitter black holes, that is, the weak cosmic censorship conjecture cannot be violated in the test field approximation. The argument relies on black hole thermodynamics (without assuming cosmic censorship), and does not depend on the precise nature of the fields. We also discuss generalizations of this result to other extremal black holes.

  3. Flexible diaphragm-extreme temperature usage

    NASA Technical Reports Server (NTRS)

    Lerma, Guillermo (Inventor)

    1991-01-01

    A diaphragm suitable for extreme temperature usage, such as encountered in critical aerospace applications, is fabricated by a unique method, and of a unique combination of materials. The materials include multilayered lay-ups of diaphragm materials sandwiched between layers of bleeder fabrics. After being formed in the desired shape on a mold, they are vacuum sealed and then cured under pressure, in a heated autoclave. A bond capable of withstanding extreme temperatures are produced.

  4. Updating upper extremity temporary prosthesis: thermoplastics.

    PubMed

    Fletchall, S; Tran, T; Ungaro, V; Hickerson, W

    1992-01-01

    Since 1989 amputees with upper-extremity burns have been fitted with a temporary prosthesis fabricated from low-temperature thermoplastic. Before 1989 conventional temporary prostheses were fabricated with plaster. The use of the thermoplastic material has produced a lightweight, cost-effective, modular system. No patients exhibited skin breakdown with the thermoplastic material. It appears that thermoplastics may be the next major breakthrough in terms of a design for a temporary upper-extremity prosthesis.

  5. Preconditioned iterations to calculate extreme eigenvalues

    SciTech Connect

    Brand, C.W.; Petrova, S.

    1994-12-31

    Common iterative algorithms to calculate a few extreme eigenvalues of a large, sparse matrix are Lanczos methods or power iterations. They converge at a rate proportional to the separation of the extreme eigenvalues from the rest of the spectrum. Appropriate preconditioning improves the separation of the eigenvalues. Davidson`s method and its generalizations exploit this fact. The authors examine a preconditioned iteration that resembles a truncated version of Davidson`s method with a different preconditioning strategy.

  6. Test fields cannot destroy extremal black holes

    NASA Astrophysics Data System (ADS)

    Natário, José; Queimada, Leonel; Vicente, Rodrigo

    2016-09-01

    We prove that (possibly charged) test fields satisfying the null energy condition at the event horizon cannot overspin/overcharge extremal Kerr-Newman or Kerr-Newman-anti de Sitter black holes, that is, the weak cosmic censorship conjecture cannot be violated in the test field approximation. The argument relies on black hole thermodynamics (without assuming cosmic censorship), and does not depend on the precise nature of the fields. We also discuss generalizations of this result to other extremal black holes.

  7. Prevention of Lower Extremity Injuries in Basketball

    PubMed Central

    Taylor, Jeffrey B.; Ford, Kevin R.; Nguyen, Anh-Dung; Terry, Lauren N.; Hegedus, Eric J.

    2015-01-01

    Context: Lower extremity injuries are common in basketball, yet it is unclear how prophylactic interventions affect lower extremity injury incidence rates. Objective: To analyze the effectiveness of current lower extremity injury prevention programs in basketball athletes, focusing on injury rates of (1) general lower extremity injuries, (2) ankle sprains, and (3) anterior cruciate ligament (ACL) tears. Data Sources: PubMed, MEDLINE, CINAHL, SPORTDiscus, and the Cochrane Register of Controlled Trials were searched in January 2015. Study Selection: Studies were included if they were randomized controlled or prospective cohort trials, contained a population of competitive basketball athletes, and reported lower extremity injury incidence rates specific to basketball players. In total, 426 individual studies were identified. Of these, 9 met the inclusion criteria. One other study was found during a hand search of the literature, resulting in 10 total studies included in this meta-analysis. Study Design: Systematic review and meta-analysis. Level of Evidence: Level 2. Data Extraction: Details of the intervention (eg, neuromuscular vs external support), size of control and intervention groups, and number of injuries in each group were extracted from each study. Injury data were classified into 3 groups based on the anatomic diagnosis reported (general lower extremity injury, ankle sprain, ACL rupture). Results: Meta-analyses were performed independently for each injury classification. Results indicate that prophylactic programs significantly reduced the incidence of general lower extremity injuries (odds ratio [OR], 0.69; 95% CI, 0.57-0.85; P < 0.001) and ankle sprains (OR, 0.45; 95% CI, 0.29-0.69; P < 0.001), yet not ACL ruptures (OR, 1.09; 95% CI, 0.36-3.29; P = 0.87) in basketball athletes. Conclusion: In basketball players, prophylactic programs may be effective in reducing the risk of general lower extremity injuries and ankle sprains, yet not ACL injuries. PMID

  8. Extreme Ultraviolet Explorer Bright Source List

    NASA Technical Reports Server (NTRS)

    Malina, Roger F.; Marshall, Herman L.; Antia, Behram; Christian, Carol A.; Dobson, Carl A.; Finley, David S.; Fruscione, Antonella; Girouard, Forrest R.; Hawkins, Isabel; Jelinsky, Patrick

    1994-01-01

    Initial results from the analysis of the Extreme Ultraviolet Explorer (EUVE) all-sky survey (58-740 A) and deep survey (67-364 A) are presented through the EUVE Bright Source List (BSL). The BSL contains 356 confirmed extreme ultraviolet (EUV) point sources with supporting information, including positions, observed EUV count rates, and the identification of possible optical counterparts. One-hundred twenty-six sources have been detected longward of 200 A.

  9. Evaluating environmental joint extremes for the offshore industry using the conditional extremes model

    NASA Astrophysics Data System (ADS)

    Ewans, Kevin; Jonathan, Philip

    2014-02-01

    Understanding extreme ocean environments and their interaction with fixed and floating structures is critical for the design of offshore and coastal facilities. The joint effect of various ocean variables on extreme responses of offshore structures is fundamental in determining the design loads. For example, it is known that mean values of wave periods tend to increase with increasing storm intensity, and a floating system responds in a complex way to both variables. Specification of joint extremes in design criteria has often been somewhat ad hoc, being based on fairly arbitrary combinations of extremes of variables estimated independently. Such approaches are even outlined in design guidelines. Mathematically more consistent estimates of the joint occurrence of extreme environmental variables fall into two camps in the offshore industry - response-based and response-independent. Both are outlined here, with emphasis on response-independent methods, particularly those based on the conditional extremes model recently introduced by (Heffernan and Tawn, 2004), which has a solid theoretical motivation. We illustrate an application of the conditional extremes model to joint estimation of extreme storm peak significant wave height and peak period at a northern North Sea location, incorporating storm direction as a model covariate. We also discuss joint estimation of extreme current profiles with depth off the North West Shelf of Australia. Methods such as the conditional extremes model provide valuable additions to the metocean engineer's toolkit.

  10. Predictability of extreme values in geophysical models

    NASA Astrophysics Data System (ADS)

    Sterk, Alef; Holland, Mark; Rabassa, Pau; Broer, Henk; Vitolo, Renato

    2014-05-01

    Classical extreme value theory studies the occurrence of unlikely large events. Extreme value theory was originally developed for time series of near-independent random variables, but in the last decade the theory has been extended to the setting of chaotic, deterministic dynamical systems. In the latter context one studies the distribution of large values in a time series generated by evaluating a scalar observable along evolutions of the system. We have studied the finite-time predictability of extreme values, such as convection, energy, and wind speeds, in three geophysical models. To that end we computed finite-time Lyapunov exponents (FTLEs) which measure the exponential growth rate of nearby trajectories over a finite time. In general, FTLEs strongly depend on the initial condition. We study whether initial conditions leading to extremes typically have a larger or smaller FTLE. Our study clearly suggests that general statements about the predictability of extreme values are not possible: the predictability of extreme values depends on (1) the observable, (2) the attractor of the system, and (3) the prediction lead time.

  11. On extreme daily precipitation totals at Athens, Greece

    NASA Astrophysics Data System (ADS)

    Nastos, P. T.; Zerefos, C. S.

    2007-04-01

    The paper studies changes in daily precipitation records at the National Observatory, Athens, during the period 1891-2004. This is the longest available time series of precipitation for Greece. The results show that both the shape and scale parameter of a fitted two parameter gamma distribution for the last two decades do show a significant difference of these parameters, when compared to any previous period from the 1890s through the 1970s. Also important changes are observed in daily precipitation totals exceeding various thresholds such as 10, 20, 30 and 50 mm. More specifically, a negative trend in the number of wet days (remarkable after 1968) and a positive trend in extreme daily precipitation are evident. The changes of heavy and extreme precipitation events in this part of SE Europe have significant environmental consequences which cause considerable damage and loss of life.

  12. Seasonal extreme value statistics for precipitation in Germany

    NASA Astrophysics Data System (ADS)

    Fischer, Madlen; Rust, Henning W.; Ulbrich, Uwe

    2013-04-01

    Extreme precipitation has a strong influence on environment, society and economy. It leads to large damage due to floods, mudslides, increased erosion or hail. While standard annual return levels are important for hydrological structures, seasonaly resolved return levels provide additional information for risk managment, e.g., for the agricultural sector. For 1208 stations in Germany, we calculate monthly resolved return levels. Instead of estimating parameters separately for every month in the year, we use a non-stationary approach and benefit from smoothly varying return levels throughout the year. This natural approach is more suitable to characterise seasonal variability of extreme precipitation and leads to more accurate return level estimates. Harmonic functions of different orders are used to describe the seasonal variation of GEV parameters and crossvalidation is used to determine a suitable model forall stations. Finally particularly vulnerable regions and associated month are investigated in more detail.

  13. American coal imports 2015

    SciTech Connect

    Frank Kolojeski

    2007-09-15

    As 2007 ends, the US coal industry passes two major milestones - the ending of the Synfuel tax break, affecting over 100M st annually, and the imposition of tighter and much more expensive safety measures, particularly in deep mines. Both of these issues, arriving at a time of wretched steam coal price levels, promise to result in a major shake up in the Central Appalachian mining sector. The report utilizes a microeconomic regional approach to determine whether either of these two schools of thought have any validity. Transport, infrastructure, competing fuels and regional issues are examined in detail and this forecasts estimates coal demand and imports on a region by region basis for the years 2010 and 2015. Some of the major highlights of the forecast are: Import growth will be driven by steam coal demand in the eastern and southern US; Transport will continue to be the key driver - we believe that inland rail rates will deter imports from being railed far inland and that the great majority of imports will be delivered directly by vessel, barge or truck to end users; Colombian coal will be the overwhelmingly dominant supply source and possesses a costs structure to enable it to compete with US-produced coal in any market conditions; Most of the growth will come from existing power plants - increasing capacity utilization at existing import facilities and other plants making investments to add imports to the supply portfolio - the growth is not dependent upon a lot of new coal fired capacity being built. Contents of the report are: Key US market dynamics; International supply dynamics; Structure of the US coal import market; and Geographic analysis.

  14. Increasing climate extremes under global warming - What is the driving force?

    NASA Astrophysics Data System (ADS)

    Yoon, J.; Wang, S. Y.; Gillies, R. R.; Hipps, L.; Kravitz, B.; Rasch, P. J.

    2015-12-01

    More climate extreme events have occurred in recent years, including the continual development of extreme drought in California, the severe cold winters in the eastern U.S. since 2014, 2015 Washington drought, and excessive wildfire events over Alaska in 2015. These have been casually attributed to global warming. However, a need for further understanding of mechanisms responsible for climate extremes is growing. In this presentation, we'll use sets of climate model simulation that designed to identify the role of the oceanic feedback in increasing climate extremes under global warming. One is with a fully coupled climate model forced by 1% ramping CO2, and the other is with an atmosphere only model forced by the same CO2 forcing. By contrasting these two, an importance of the oceanic feedback in increasing climate extremes under global warming can be diagnosed.

  15. Seasonal and regional variations in extreme precipitation event frequency using CMIP5

    NASA Astrophysics Data System (ADS)

    Janssen, E.; Sriver, R. L.; Wuebbles, D. J.; Kunkel, K. E.

    2016-05-01

    Understanding how the frequency and intensity of extreme precipitation events are changing is important for regional risk assessments and adaptation planning. Here we use observational data and an ensemble of climate change model experiments (from the Coupled Model Intercomparison Project Phase 5 (CMIP5)) to examine past and potential future seasonal changes in extreme precipitation event frequency over the United States. Using the extreme precipitation index as a metric for extreme precipitation change, we find key differences between models and observations. In particular, the CMIP5 models tend to overestimate the number of spring events and underestimate the number of summer events. This seasonal shift in the models is amplified in projections. These results provide a basis for evaluating climate model skill in simulating observed seasonality and changes in regional extreme precipitation. Additionally, we highlight key sources of variability and uncertainty that can potentially inform regional impact analyses and adaptation planning.

  16. Sensitivity of precipitation extremes to radiative forcing of greenhouse gases and aerosols

    NASA Astrophysics Data System (ADS)

    Lin, Lei; Wang, Zhili; Xu, Yangyang; Fu, Qiang

    2016-09-01

    Greenhouse gases (GHGs) and aerosols are the two most important anthropogenic forcing agents in the 21st century. The expected declines of anthropogenic aerosols in the 21st century from present-day levels would cause an additional warming of the Earth's climate system, which would aggravate the climate extremes caused by GHG warming. We examine the increased rate of precipitation extremes with global mean surface warming in the 21st century caused by anthropogenic GHGs and aerosols, using an Earth system model ensemble simulation. Similar to mean precipitation, the increased rate of precipitation extremes caused by aerosol forcing is significantly larger than that caused by GHG forcing. The aerosol forcing in the coming decades can play a critical role in inducing change in precipitation extremes if a lower GHG emission pathway is adopted. Our results have implications for policy-making on climate adaptation to extreme precipitation events.

  17. The Influence of Recurrent Modes of Climate Variability on the Occurrence of Extreme Temperatures over North America

    NASA Astrophysics Data System (ADS)

    Loikith, P.; Broccoli, A. J.

    2012-12-01

    The influence of the Pacific North American (PNA) pattern, the Northern Annular Mode (NAM), and the El Niño-Southern Oscillation (ENSO) on extreme temperature days and months over North America is examined. Associations between extreme temperature days and months are strongest with the PNA and NAM and weaker for ENSO. In general, the association with extremes tends to be stronger on monthly than daily time scales. Extreme temperatures are associated with the PNA and NAM in locations typically influenced by these circulation patterns; however many extremes still occur on days when the amplitude and polarity of these patterns do not favor their occurrence. In winter, synoptic-scale, transient weather disturbances are important drivers of extreme temperature days; however these smaller-scale events are often concurrent with amplified PNA or NAM patterns. Associations are weaker in summer when other physical mechanisms affecting the surface energy balance, such as anomalous soil moisture content, are associated with extreme temperatures.

  18. Lower extremity finite element model for crash simulation

    SciTech Connect

    Schauer, D.A.; Perfect, S.A.

    1996-03-01

    A lower extremity model has been developed to study occupant injury mechanisms of the major bones and ligamentous soft tissues resulting from vehicle collisions. The model is based on anatomically correct digitized bone surfaces of the pelvis, femur, patella and the tibia. Many muscles, tendons and ligaments were incrementally added to the basic bone model. We have simulated two types of occupant loading that occur in a crash environment using a non-linear large deformation finite element code. The modeling approach assumed that the leg was passive during its response to the excitation, that is, no active muscular contraction and therefore no active change in limb stiffness. The approach recognized that the most important contributions of the muscles to the lower extremity response are their ability to define and modify the impedance of the limb. When nonlinear material behavior in a component of the leg model was deemed important to response, a nonlinear constitutive model was incorporated. The accuracy of these assumptions can be verified only through a review of analysis results and careful comparison with test data. As currently defined, the model meets the objective for which it was created. Much work remains to be done, both from modeling and analysis perspectives, before the model can be considered complete. The model implements a modeling philosophy that can accurately capture both kinematic and kinetic response of the lower limb. We have demonstrated that the lower extremity model is a valuable tool for understanding the injury processes and mechanisms. We are now in a position to extend the computer simulation to investigate the clinical fracture patterns observed in actual crashes. Additional experience with this model will enable us to make a statement on what measures are needed to significantly reduce lower extremity injuries in vehicle crashes. 6 refs.

  19. Neurodevelopmental problems and extremes in BMI

    PubMed Central

    Tajnia, Armin; Lichtenstein, Paul; Lundström, Sebastian; Anckarsäter, Henrik; Nilsson, Thomas; Råstam, Maria

    2015-01-01

    Background. Over the last few decades, an increasing number of studies have suggested a connection between neurodevelopmental problems (NDPs) and body mass index (BMI). Attention deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASD) both seem to carry an increased risk for developing extreme BMI. However, the results are inconsistent, and there have been only a few studies of the general population of children. Aims. We had three aims with the present study: (1) to define the prevalence of extreme (low or high) BMI in the group of children with ADHD and/or ASDs compared to the group of children without these NDPs; (2) to analyze whether extreme BMI is associated with the subdomains within the diagnostic categories of ADHD or ASD; and (3) to investigate the contribution of genetic and environmental factors to BMI in boys and girls at ages 9 and 12. Method. Parents of 9- or 12-year-old twins (n = 12,496) were interviewed using the Autism—Tics, ADHD and other Comorbidities (A-TAC) inventory as part of the Child and Adolescent Twin Study in Sweden (CATSS). Univariate and multivariate generalized estimated equation models were used to analyze associations between extremes in BMI and NDPs. Results. ADHD screen-positive cases followed BMI distributions similar to those of children without ADHD or ASD. Significant association was found between ADHD and BMI only among 12-year-old girls, where the inattention subdomain of ADHD was significantly associated with the high extreme BMI. ASD scores were associated with both the low and the high extremes of BMI. Compared to children without ADHD or ASD, the prevalence of ASD screen-positive cases was three times greater in the high extreme BMI group and double as much in the low extreme BMI group. Stereotyped and repetitive behaviors were significantly associated with high extreme BMIs. Conclusion. Children with ASD, with or without coexisting ADHD, are more prone to have low or high extreme BMIs than children

  20. The Pace of Perceivable Extreme Climate Change

    NASA Astrophysics Data System (ADS)

    Tan, X.; Gan, T. Y.

    2015-12-01

    When will the signal of obvious changes in extreme climate emerge over climate variability (Time of Emergence, ToE) is a key question for planning and implementing measures to mitigate the potential impact of climate change to natural and human systems that are generally adapted to potential changes from current variability. We estimated ToEs for the magnitude, duration and frequency of global extreme climate represented by 24 extreme climate indices (16 for temperature and 8 for precipitation) with different thresholds of the signal-to-noise (S/N) ratio based on projections of CMIP5 global climate models under RCP8.5 and RCP4.5 for the 21st century. The uncertainty of ToE is assessed by using 3 different methods to calculate S/N for each extreme index. Results show that ToEs of the projected extreme climate indices based on the RCP4.5 climate scenarios are generally projected to happen about 20 years later than that for the RCP8.5 climate scenarios. Under RCP8.5, the projected magnitude, duration and frequency of extreme temperature on Earth will all exceed 2 standard deviations by 2100, and the empirical 50th percentile of the global ToE for the frequency and magnitude of hot (cold) extreme are about 2040 and 2054 (2064 and 2054) for S/N > 2, respectively. The 50th percentile of global ToE for the intensity of extreme precipitation is about 2030 and 2058 for S/N >0.5 and S/N >1, respectively. We further evaluated the exposure of ecosystems and human societies to the pace of extreme climate change by determining the year of ToE for various extreme climate indices projected to occur over terrestrial biomes, marine realms and major urban areas with large populations. This was done by overlaying terrestrial, ecoregions and population maps with maps of ToE derived, to extract ToEs for these regions. Possible relationships between GDP per person and ToE are also investigated by relating the mean ToE for each country and its average value of GDP per person.

  1. Large Scale Meteorological Pattern of Extreme Rainfall in Indonesia

    NASA Astrophysics Data System (ADS)

    Kuswanto, Heri; Grotjahn, Richard; Rachmi, Arinda; Suhermi, Novri; Oktania, Erma; Wijaya, Yosep

    2014-05-01

    Extreme Weather Events (EWEs) cause negative impacts socially, economically, and environmentally. Considering these facts, forecasting EWEs is crucial work. Indonesia has been identified as being among the countries most vulnerable to the risk of natural disasters, such as floods, heat waves, and droughts. Current forecasting of extreme events in Indonesia is carried out by interpreting synoptic maps for several fields without taking into account the link between the observed events in the 'target' area with remote conditions. This situation may cause misidentification of the event leading to an inaccurate prediction. Grotjahn and Faure (2008) compute composite maps from extreme events (including heat waves and intense rainfall) to help forecasters identify such events in model output. The composite maps show large scale meteorological patterns (LSMP) that occurred during historical EWEs. Some vital information about the EWEs can be acquired from studying such maps, in addition to providing forecaster guidance. Such maps have robust mid-latitude meteorological patterns (for Sacramento and California Central Valley, USA EWEs). We study the performance of the composite approach for tropical weather condition such as Indonesia. Initially, the composite maps are developed to identify and forecast the extreme weather events in Indramayu district- West Java, the main producer of rice in Indonesia and contributes to about 60% of the national total rice production. Studying extreme weather events happening in Indramayu is important since EWEs there affect national agricultural and fisheries activities. During a recent EWE more than a thousand houses in Indramayu suffered from serious flooding with each home more than one meter underwater. The flood also destroyed a thousand hectares of rice plantings in 5 regencies. Identifying the dates of extreme events is one of the most important steps and has to be carried out carefully. An approach has been applied to identify the

  2. Hydrometeorological extremes in the Mediterranean area

    NASA Astrophysics Data System (ADS)

    Llasat, M. C.; Rigo, T.

    2003-04-01

    Between the 9th and 18th of November of 2001, a succession of hydrometeorological hazards affected the West of the Mediterranean area. High rainfalls above 200mm /24 h gave place to catastrophic floods in Algeria, Balearic Islands, Morocco and the Northeast of the Iberian Peninsula; extreme winds of more than 30 m/s of sustained speed uprooted thousands of trees, removed up to 50 per cent of the sand in a great number of beaches of the Balearic Islands and Catalonia and made waves over 11 m high; combined with the wind, the hail destroyed the crops in the littoral region of Catalonia, whereas a cold wave affected the rest of Spain, with the snow arriving to Catalonia. Over 600 people died in Algeria and up to 10 in Spain, with material damage up to 150M euros. In this case a strong cyclone was identified as one of the main causes of the severe weather produced. A study developed into the framework of the MEDEX project shows that the Gulf of Genoa (mainly medium and deep cyclones) and the Iberian Peninsula (mainly shallow cyclones) are the most cyclogenesis prone areas in the West Mediterranean (Campins et al, 2002). Although the West part of the Mediterranean shows the maximum number of cyclones, it is also important in the Eastern part (smoothed values are, respectively, 437 and 353, following the results of Gil et al, 2002). Although the events of November 2001 are not usual in the Mediterranean area, hydrometeorological hazards that affect more than one country (usually Spain, France and Italy) are frequent. But not all the catastrophic events are so vast. On the 25th of September of 1962 a catastrophic flash-flood produced 815 casualties in less than 150 km2 and on the 10th of June of 2000, more than 200 mm were recorded in less than 3 hours. Although the Mediterranean climate is identified with dry summers, that season shows the greatest rate of convective events (Llasat, 2001) that can lead to flash floods in little catchments, usually in mountain and coastal

  3. Addressing Extremes within the WCRP - GEWEX Framework

    NASA Astrophysics Data System (ADS)

    van Oevelen, P. J.; Stewart, R.; Detemmerman, V.

    2008-12-01

    For large international coordination programs such as the Global Energy and Water Cycle Experiment (GEWEX) as part of the World Climate Research Programme (WCRP) it is difficult to strike a good balance between enabling as much international involvement as is possible and desirable and the achievability of the objectives. WCRP has decided that "Extremes Research" is one of several areas where it would like to see its efforts strengthened and scientific research pushed forward. The foci that are being selected should be phrased such that they are practical and achievable within a time span of 1 to 3 years. Preferably these foci build upon the expertise from cross WCRP activities and are not restricted to single core project activities. In this presentation an overview will be given of the various activities within GEWEX that are related to extremes and which ones would be most ideal to be addressed as WCRP foci from a GEWEX perspective. The rationale and context of extreme research will be presented as well links to other national and international programs. "Extremes Research" as a topic is attractive since it has a high societal relevance and impact. However, numerous definitions of extremes exist and they are being used in widely varying contexts making it not always clear of what exactly is being addressed. This presentation will give an outlook on what can be expected research wise in the near future based upon the outcomes of the Extremes Workshop organised last June in Vancouver in the context of the Coordinated Energy and water cycle Observations Project (CEOP) as part of GEWEX. In particular it will be shown how these activities, which will only address certain types of extremes, can be linked to adaptation and mitigation efforts taking place in other organisations and by national and international bodies.

  4. Eukaryotic diversity at pH extremes.

    PubMed

    Amaral-Zettler, Linda A

    2012-01-01

    Extremely acidic (pH < 3) and extremely alkaline (pH > 9) environments support a diversity of single-cell and to a lesser extent, multicellular eukaryotic life. This study compared alpha and beta diversity in eukaryotic communities from seven diverse aquatic environments with pH values ranging from 2 to 11 using massively-parallel pyrotag sequencing targeting the V9 hypervariable region of the 18S ribosomal RNA (rRNA) gene. A total of 946 operational taxonomic units (OTUs) were recovered at a 6% cut-off level (94% similarity) across the sampled environments. Hierarchical clustering of the samples segregated the communities into acidic and alkaline groups. Similarity percentage (SIMPER) analysis followed by indicator OTU analysis (IOA) and non-metric multidimensional scaling (NMDS) were used to determine which characteristic groups of eukaryotic taxa typify acidic or alkaline extremes and the extent to which pH explains eukaryotic community structure in these environments. Spain's Rio Tinto yielded the fewest observed OTUs while Nebraska Sandhills alkaline lakes yielded the most. Distinct OTUs, including metazoan OTUs, numerically dominated pH extreme sites. Indicator OTUs included the diatom Pinnularia and unidentified opisthokonts (Fungi and Filasterea) in the extremely acidic environments, and the ciliate Frontonia across the extremely alkaline sites. Inferred from NMDS, pH explained only a modest fraction of the variation across the datasets, indicating that other factors influence the underlying community structure in these environments. The findings from this study suggest that the ability for eukaryotes to adapt to pH extremes over a broad range of values may be rare, but further study of taxa that can broadly adapt across diverse acidic and alkaline environments, respectively present good models for understanding adaptation and should be targeted for future investigations.

  5. Eukaryotic diversity at pH extremes

    PubMed Central

    Amaral-Zettler, Linda A.

    2013-01-01

    Extremely acidic (pH < 3) and extremely alkaline (pH > 9) environments support a diversity of single-cell and to a lesser extent, multicellular eukaryotic life. This study compared alpha and beta diversity in eukaryotic communities from seven diverse aquatic environments with pH values ranging from 2 to 11 using massively-parallel pyrotag sequencing targeting the V9 hypervariable region of the 18S ribosomal RNA (rRNA) gene. A total of 946 operational taxonomic units (OTUs) were recovered at a 6% cut-off level (94% similarity) across the sampled environments. Hierarchical clustering of the samples segregated the communities into acidic and alkaline groups. Similarity percentage (SIMPER) analysis followed by indicator OTU analysis (IOA) and non-metric multidimensional scaling (NMDS) were used to determine which characteristic groups of eukaryotic taxa typify acidic or alkaline extremes and the extent to which pH explains eukaryotic community structure in these environments. Spain's Rio Tinto yielded the fewest observed OTUs while Nebraska Sandhills alkaline lakes yielded the most. Distinct OTUs, including metazoan OTUs, numerically dominated pH extreme sites. Indicator OTUs included the diatom Pinnularia and unidentified opisthokonts (Fungi and Filasterea) in the extremely acidic environments, and the ciliate Frontonia across the extremely alkaline sites. Inferred from NMDS, pH explained only a modest fraction of the variation across the datasets, indicating that other factors influence the underlying community structure in these environments. The findings from this study suggest that the ability for eukaryotes to adapt to pH extremes over a broad range of values may be rare, but further study of taxa that can broadly adapt across diverse acidic and alkaline environments, respectively present good models for understanding adaptation and should be targeted for future investigations. PMID:23335919

  6. Analyzing Spatiotemporal Patterns of Extreme Precipitation Events in Southeastern Anatolia

    NASA Astrophysics Data System (ADS)

    Ozcan, O.; Bookhagen, B.; Musaoglu, N.

    2013-10-01

    Extreme environmental events, such as floods, droughts, rainstorms, and strong winds have severe consequences for human society. Changes in extreme weather and climate events have significant impacts and are among the most serious challenges to society in coping with a changing climate. The cost of damage caused by extreme climate events is rising all over the world. The European Environment Agency (EEA) report ("Climate Change, Impacts and Vulnerabilities in Europe 2012") stated that the cost of damage had increased from € 9 billion in the 1980s to € 13 billions in the 2000s. In the United States, the National Oceanic and Atmospheric Administration (NOAA) reported that 188 billion in damage was caused by the severe weather events in 2011 and 2012. Understanding and identifying hydrometeorologic extreme events and their changes through time are key in sustaining agriculture and socio-economic development. Planning for weather-related emergencies, agricultural and reservoir management and insurance risk calculations, all rely on knowledge of the frequency of these extreme events. The assessment of extreme precipitation is an important problem in hydrologic risk analysis and design. Erosion and removal of the fertile soil layer through hydroclimatic extreme events is also a serious problem in semi-arid to arid regions, especially in mediterranean climates. Accurate measurements of precipitation on a variety of space and time scales are important to climate scientists and decision makers, including hydrologists, agriculturalists and emergency managers. The historical record of precipitation observations is limited mostly to land areas where rain gauges can be deployed, and measurements from those instruments are sparse over large and meteorologically important regions of the Turkey, such as over the Southeastern Anatolia Region. While rain gauge measurements are often used to tune hydrologic models, they are limited by their spatial coverage. Remote sensing

  7. Import and nuclear size

    PubMed Central

    Cohen-Fix, Orna

    2012-01-01

    The size of a cell’s nucleus is usually proportional to the size of the cell itself. How are the two linked? The answer lies, at least in part, in the import of one or more cytoplasmic cargoes into the nucleus. PMID:21107417

  8. Importance of controls

    SciTech Connect

    Schilling, J.

    1995-08-01

    The importance of NO{sub x} boiler control methods is outlined: the following topics are discussed: boiler problems; environmental problems; NO{sub x} control methods; low excess air control; low NO{sub x} burners; flue gas recirculation; staged air combustion; fuel reburning; switching/dual fuels; selective non-catalytic reduction (SNCR); and selective catalytic reduction (SCR). Final recommendations are presented.

  9. Impacts of Climate Extremes on Gross Primary Productivity at Multiple Spatial Scales

    NASA Astrophysics Data System (ADS)

    Kim, Soyoun; Ryu, Youngryel; Jiang, Chongya

    2016-04-01

    Climate extreme events have made significant impacts on terrestrial carbon cycles. Recent studies on detection and attribution of climate extreme events and their impact on carbon cycles used coarse spatial resolution data such as 0.5 degree. The coarse resolution data might miss important climate extremes and their impacts on GPP. To fill this research gap, we use a new global GPP product derived from a process-based model, the Breathing Earth System Simulator (BESS). The BESS takes full advantages of MODIS/AVHRR land and atmosphere products, providing global GPP product in 1 km resolution from 2000 to 2015 and 1/12 degree resolution from 1982 to 1999. We first integrate the BESS GPP products to 0.5 degree (1982-2015) and apply the method of Zscheischler et al. (2013). To test the impacts of spatial resolutions on detecting extreme events, we enhance spatial resolutions of the BESS GPP from 0.5 degree to 0.25, 0.125, and 1/12 degrees and quantify the variations of areas which experienced climate extremes. We subsequently investigate hotspot regions where the extremes occur using fine resolution GPP data at 1/12 degree (1982-2015), then analyze the causes of the extreme events that substantially decreased GPP by using precipitation, air temperature, and frost. This study could improve the understanding of the relationship between climate extremes and the carbon cycle at multiple spatial scales.

  10. Amplitude and frequency of temperature extremes over the North Atlantic region

    NASA Astrophysics Data System (ADS)

    Nogaj, M.; Yiou, P.; Parey, S.; Malek, F.; Naveau, P.

    2006-05-01

    Recent studies on extreme events have focused on the potential change of their intensity during the 20th century, but their frequency evolution has often been overlooked although its socio-economic impact is equally important. This paper focuses on extreme events of high and low temperatures and their amplitude and frequency changes over the last 60 years in the North Atlantic (NA) region. We analyze the temporal evolution of the amplitude and frequency of extreme events through the parameters of an extreme value distribution applied to NCEP reanalysis for the winter and summer seasons. We examine the relation of the statistics of extremes with greenhouse gas forcing and an atmospheric circulation index and obtain a spatial distribution of the trends of those extreme parameters. We find that the frequency of warm extremes increases over most of the NA while their magnitude does not vary as systematically. Apart from the Labrador Sea and parts of Scandinavia, the features of winter cold extremes exhibit decreasing or no trends.

  11. Analysis of climate variability in mainland Portugal using a combined Climate Extremes Index

    NASA Astrophysics Data System (ADS)

    Espírito Santo, Fátima; de Lima, Isabel P.

    2014-05-01

    Monitoring changes in climate extremes is important because of their potential severe impacts on the environment and the society. Due to its geographical situation, mainland Portugal shows important spatial gradients in precipitation and air temperature and is prone to the occurrence of extreme weather and climate events, such as heat waves, droughts and floods. Thus, there is a need to understand regional specificities in the changes of occurrence of these events in the territory that could require special attention in the prospect of operational climate change adaptation and mitigation measures, to be adopted at the regional scale. For this purpose, a modified combined Climate Extremes Index (CEI) is proposed here, for mainland Portugal. This index consists of five component indicators of air temperature and precipitation extremes and was developed to measure the percentage of area affected by these extremes. Therefore, we use this index to analyse changes in the fraction of the country experiencing extremes (cold, hot, dry, wet), at the annual and seasonal scales, after 1941. At the annual scale, results show an increase in the extent of hot and dry extremes and a decrease in the extent of cold and wet extremes over the whole country, although only the results obtained for the air temperature are statistically significant. Since the mid-1970s, the fraction of the area of mainland Portugal experiencing maximum and minimum temperatures much above normal has increased significantly. An increasing trend in the area experiencing drought conditions and with a much greater-than-normal number of dry days is also noted in the last decades. At the seasonal scale, spring, summer and winter show a significant increase in the extent of hot extremes and a decrease in the extent of cold extremes. For all seasons, the fraction of the area experiencing drought conditions increased, whereas in spring and autumn the fraction of the area experiencing wet conditions decreased. In

  12. Extreme Rainfall Impacts in Fractured Permeable Catchments

    NASA Astrophysics Data System (ADS)

    Ireson, A. M.; Butler, A. P.

    2009-12-01

    of recharge: under low rainfall intensities recharge is slow (lags of > 100 days) and through the matrix; under moderate intensities recharge is via the matrix and partially saturated fractures (lags of 10s of days) and, if sustained, can lead to flooding (as in 2000/1); under high intensity rainfall fractures transmit rainfall preferentially, leading to a large, rapid (<1 day) water table response. Given the expectation that extreme rainfall events are likely to become more frequent and intense, our main focus is the preferential recharge mechanism, which has the potential to cause rapid flooding. By examining rainfall-water table response patterns, we demonstrate how the combined intensity-duration characteristics of rainfall events can be used to predict when preferential recharge is likely to occur. A 2D physically based, dual permeability Richards' equation model of the Chalk, which fully couples the unsaturated/saturated zones was developed and conditioned on field observations. This was used in a sensitivity study of water table response to a wide range of rainfall conditions, such as might be expected under future climate scenarios. The model also demonstrated the importance of the soil and weathered chalk layers on matrix and fracture flow response to rainfall infiltration.

  13. Multidecadal oscillations in rainfall and hydrological extremes

    NASA Astrophysics Data System (ADS)

    Willems, Patrick

    2013-04-01

    Many studies have anticipated a worldwide increase in the frequency and intensity of precipitation extremes and floods since the last decade(s). Natural variability by climate oscillations partly determines the observed evolution of precipitation extremes. Based on a technique for the identification and analysis of changes in extreme quantiles, it is shown that hydrological extremes have oscillatory behaviour at multidecadal time scales. Results are based on nearly independent extremes extracted from long-term historical time series of precipitation intensities and river flows. Study regions include Belgium - The Netherlands (Meuse basin), Ethiopia (Blue Nile basin) and Ecuador (Paute basin). For Belgium - The Netherlands, the past 100 years showed larger and more hydrological extremes around the 1910s, 1950-1960s, and more recently during the 1990-2000s. Interestingly, the oscillations for southwestern Europe are anti-correlated with these of northwestern Europe, thus with oscillation highs in the 1930-1940s and 1970s. The precipitation oscillation peaks are explained by persistence in atmospheric circulation patterns over the North Atlantic during periods of 10 to 15 years. References: Ntegeka V., Willems P. (2008), 'Trends and multidecadal oscillations in rainfall extremes, based on a more than 100 years time series of 10 minutes rainfall intensities at Uccle, Belgium', Water Resources Research, 44, W07402, doi:10.1029/2007WR006471 Mora, D., Willems, P. (2012), 'Decadal oscillations in rainfall and air temperature in the Paute River Basin - Southern Andes of Ecuador', Theoretical and Applied Climatology, 108(1), 267-282, doi:0.1007/s00704-011-0527-4 Taye, M.T., Willems, P. (2011). 'Influence of climate variability on representative QDF predictions of the upper Blue Nile Basin', Journal of Hydrology, 411, 355-365, doi:10.1016/j.jhydrol.2011.10.019 Taye, M.T., Willems, P. (2012). 'Temporal variability of hydro-climatic extremes in the Blue Nile basin', Water

  14. How does public opinion become extreme?

    PubMed Central

    Ramos, Marlon; Shao, Jia; Reis, Saulo D. S.; Anteneodo, Celia; Andrade, José S.; Havlin, Shlomo; Makse, Hernán A.

    2015-01-01

    We investigate the emergence of extreme opinion trends in society by employing statistical physics modeling and analysis on polls that inquire about a wide range of issues such as religion, economics, politics, abortion, extramarital sex, books, movies, and electoral vote. The surveys lay out a clear indicator of the rise of extreme views. The precursor is a nonlinear relation between the fraction of individuals holding a certain extreme view and the fraction of individuals that includes also moderates, e.g., in politics, those who are “very conservative” versus “moderate to very conservative” ones. We propose an activation model of opinion dynamics with interaction rules based on the existence of individual “stubbornness” that mimics empirical observations. According to our modeling, the onset of nonlinearity can be associated to an abrupt bootstrap-percolation transition with cascades of extreme views through society. Therefore, it represents an early-warning signal to forecast the transition from moderate to extreme views. Moreover, by means of a phase diagram we can classify societies according to the percolative regime they belong to, in terms of critical fractions of extremists and people’s ties. PMID:25989484

  15. Extreme Metal Music and Anger Processing

    PubMed Central

    Sharman, Leah; Dingle, Genevieve A.

    2015-01-01

    The claim that listening to extreme music causes anger, and expressions of anger such as aggression and delinquency have yet to be substantiated using controlled experimental methods. In this study, 39 extreme music listeners aged 18–34 years were subjected to an anger induction, followed by random assignment to 10 min of listening to extreme music from their own playlist, or 10 min silence (control). Measures of emotion included heart rate and subjective ratings on the Positive and Negative Affect Scale (PANAS). Results showed that ratings of PANAS hostility, irritability, and stress increased during the anger induction, and decreased after the music or silence. Heart rate increased during the anger induction and was sustained (not increased) in the music condition, and decreased in the silence condition. PANAS active and inspired ratings increased during music listening, an effect that was not seen in controls. The findings indicate that extreme music did not make angry participants angrier; rather, it appeared to match their physiological arousal and result in an increase in positive emotions. Listening to extreme music may represent a healthy way of processing anger for these listeners. PMID:26052277

  16. How does public opinion become extreme?

    PubMed

    Ramos, Marlon; Shao, Jia; Reis, Saulo D S; Anteneodo, Celia; Andrade, José S; Havlin, Shlomo; Makse, Hernán A

    2015-01-01

    We investigate the emergence of extreme opinion trends in society by employing statistical physics modeling and analysis on polls that inquire about a wide range of issues such as religion, economics, politics, abortion, extramarital sex, books, movies, and electoral vote. The surveys lay out a clear indicator of the rise of extreme views. The precursor is a nonlinear relation between the fraction of individuals holding a certain extreme view and the fraction of individuals that includes also moderates, e.g., in politics, those who are "very conservative" versus "moderate to very conservative" ones. We propose an activation model of opinion dynamics with interaction rules based on the existence of individual "stubbornness" that mimics empirical observations. According to our modeling, the onset of nonlinearity can be associated to an abrupt bootstrap-percolation transition with cascades of extreme views through society. Therefore, it represents an early-warning signal to forecast the transition from moderate to extreme views. Moreover, by means of a phase diagram we can classify societies according to the percolative regime they belong to, in terms of critical fractions of extremists and people's ties. PMID:25989484

  17. How does public opinion become extreme?

    PubMed

    Ramos, Marlon; Shao, Jia; Reis, Saulo D S; Anteneodo, Celia; Andrade, José S; Havlin, Shlomo; Makse, Hernán A

    2015-05-19

    We investigate the emergence of extreme opinion trends in society by employing statistical physics modeling and analysis on polls that inquire about a wide range of issues such as religion, economics, politics, abortion, extramarital sex, books, movies, and electoral vote. The surveys lay out a clear indicator of the rise of extreme views. The precursor is a nonlinear relation between the fraction of individuals holding a certain extreme view and the fraction of individuals that includes also moderates, e.g., in politics, those who are "very conservative" versus "moderate to very conservative" ones. We propose an activation model of opinion dynamics with interaction rules based on the existence of individual "stubbornness" that mimics empirical observations. According to our modeling, the onset of nonlinearity can be associated to an abrupt bootstrap-percolation transition with cascades of extreme views through society. Therefore, it represents an early-warning signal to forecast the transition from moderate to extreme views. Moreover, by means of a phase diagram we can classify societies according to the percolative regime they belong to, in terms of critical fractions of extremists and people's ties.

  18. Lower extremity muscle activation during baseball pitching.

    PubMed

    Campbell, Brian M; Stodden, David F; Nixon, Megan K

    2010-04-01

    The purpose of this study was to investigate muscle activation levels of select lower extremity muscles during the pitching motion. Bilateral surface electromyography data on 5 lower extremity muscles (biceps femoris, rectus femoris, gluteus maximus, vastus medialis, and gastrocnemius) were collected on 11 highly skilled baseball pitchers and compared with individual maximal voluntary isometric contraction (MVIC) data. The pitching motion was divided into 4 distinct phases: phase 1, initiation of pitching motion to maximum stride leg knee height; phase 2, maximum stride leg knee height to stride foot contact (SFC); phase 3, SFC to ball release; and phase 4, ball release to 0.5 seconds after ball release (follow-through). Results indicated that trail leg musculature elicited moderate to high activity levels during phases 2 and 3 (38-172% of MVIC). Muscle activity levels of the stride leg were moderate to high during phases 2-4 (23-170% of MVIC). These data indicate a high demand for lower extremity strength and endurance. Specifically, coaches should incorporate unilateral and bilateral lower extremity exercises for strength improvement or maintenance and to facilitate dynamic stabilization of the lower extremities during the pitching motion.

  19. Extreme value theory for singular measures.

    PubMed

    Lucarini, Valerio; Faranda, Davide; Turchetti, Giorgio; Vaienti, Sandro

    2012-06-01

    In this paper, we perform an analytical and numerical study of the extreme values of specific observables of dynamical systems possessing an invariant singular measure. Such observables are expressed as functions of the distance of the orbit of initial conditions with respect to a given point of the attractor. Using the block maxima approach, we show that the extremes are distributed according to the generalised extreme value distribution, where the parameters can be written as functions of the information dimension of the attractor. The numerical analysis is performed on a few low dimensional maps. For the Cantor ternary set and the Sierpinskij triangle, which can be constructed as iterated function systems, the inferred parameters show a very good agreement with the theoretical values. For strange attractors like those corresponding to the Lozi and Hènon maps, a slower convergence to the generalised extreme value distribution is observed. Nevertheless, the results are in good statistical agreement with the theoretical estimates. It is apparent that the analysis of extremes allows for capturing fundamental information of the geometrical structure of the attractor of the underlying dynamical system, the basic reason being that the chosen observables act as magnifying glass in the neighborhood of the point from which the distance is computed.

  20. How does public opinion become extreme?

    NASA Astrophysics Data System (ADS)

    Ramos, Marlon; Shao, Jia; Reis, Saulo D. S.; Anteneodo, Celia; Andrade, José S.; Havlin, Shlomo; Makse, Hernán A.

    2015-05-01

    We investigate the emergence of extreme opinion trends in society by employing statistical physics modeling and analysis on polls that inquire about a wide range of issues such as religion, economics, politics, abortion, extramarital sex, books, movies, and electoral vote. The surveys lay out a clear indicator of the rise of extreme views. The precursor is a nonlinear relation between the fraction of individuals holding a certain extreme view and the fraction of individuals that includes also moderates, e.g., in politics, those who are “very conservative” versus “moderate to very conservative” ones. We propose an activation model of opinion dynamics with interaction rules based on the existence of individual “stubbornness” that mimics empirical observations. According to our modeling, the onset of nonlinearity can be associated to an abrupt bootstrap-percolation transition with cascades of extreme views through society. Therefore, it represents an early-warning signal to forecast the transition from moderate to extreme views. Moreover, by means of a phase diagram we can classify societies according to the percolative regime they belong to, in terms of critical fractions of extremists and people’s ties.

  1. Climate extremes in the amazon basin

    NASA Astrophysics Data System (ADS)

    Marengo, José; Mendes, David

    2010-05-01

    Changes in extreme weather and climate events have significant impacts and are among the most serious challenges to society in coping with a changing climate (CCSP, 2008). Indeed, according to IPCC AR4, confidence has increased that some extremes will become more frequent, more widespread and/or more intense during the 21st century . Until recently, there had been little published work on rainfall extremes in South America, and emphasis has been given to the La Plata Basin, where data coverage is much better. In this study, we use the indices of extremes derived by the WMO and used for the IPCC AR4 applied to 100 stations in Amazon Basin for the period from 1971 to 2005, with focus on rainfall extremes. The quality control involved carefully evaluating numerous detailed graphs of daily data to detect evidence of possible quality issues with the data as well as statistically identifying outliers. Each outlier or potential data problem was manually validated using metadata information of our climate data.

  2. Impacts of Irrigation on Daily Extremes in the Coupled Climate System

    NASA Technical Reports Server (NTRS)

    Puma, Michael J.; Cook, Benjamin I.; Krakauer, Nir; Gentine, Pierre; Nazarenka, Larissa; Kelly, Maxwell; Wada, Yoshihide

    2014-01-01

    Widespread irrigation alters regional climate through changes to the energy and water budgets of the land surface. Within general circulation models, simulation studies have revealed significant changes in temperature, precipitation, and other climate variables. Here we investigate the feedbacks of irrigation with a focus on daily extremes at the global scale. We simulate global climate for the year 2000 with and without irrigation to understand irrigation-induced changes. Our simulations reveal shifts in key climate-extreme metrics. These findings indicate that land cover and land use change may be an important contributor to climate extremes both locally and in remote regions including the low-latitudes.

  3. [Diagnosing imported helminthiasis].

    PubMed

    Pardo, Javier; Pérez-Arellano, José Luis; Galindo, Inmaculada; Belhassen, Moncef; Cordero, Miguel; Muro, Antonio

    2007-05-01

    In recent years, there has been an increase in cases of imported helminthiasis in Spain because of two complementary causes: immigration and international travel. Although the prevalence of helminthiasis is high in the immigrant population, the risk of transmission to the Spanish population is low. In this review, we provide clues to aid in the diagnosis of the helminthiasis, highlighting the geographic characteristics, clinical findings and analytical results of the most frequent types. The low sensitivity of the classic parasitological diagnostic test, mainly in tissue helminthiasis, is described. In addition, the advantages and limitations of the common serological methods for detecting related circulating antigens and antibodies are presented. Certain molecular methods used in the diagnosis of imported helminthiasis and the best strategies for screening of this condition are discussed.

  4. Changes in Tropical Precipitation Extremes: Secular or Cyclical?

    NASA Astrophysics Data System (ADS)

    Vuruputur, Venugopal; Sukhatme, Jai

    2016-04-01

    An appropriate measure of the wet/dryness of a region is its annual accumulation. Using GPCP and GPCC data, we provide evidence that the probability of encountering very high and very low annual tropical rainfall has increased significantly during 1998-2013, as compared to the preceding warming era (1979-1997). These changes are spatially coherent and comprise of a rearrangement of very wet regions and a systematic expansion of dry zones. While the increased likelihood of extremes is consistent with a higher average temperature during the pause (as compared to 1979-1997), it is important to note that the periods considered are also characterized by a transition from a relatively warm to cold phase of the El Niño Southern Oscillation (ENSO). To further probe the relation between contrasting phases of ENSO and extremes in accumulation, a similar comparison is performed between 1960-1978 (another extended cold phase of ENSO) and the aforementioned warming era. Remarkably, in this cold-to-warm transition, a near-exact reversal of extremes is noted both statistically and geographically. This is despite the average temperature being higher in 1979-1997 as compared to 1960-1978. Thus, in addition to exerting a dominant influence on the wet/dryness of a region, the imprint of changing phases of ENSO is clearly seen in the waxing and waning of extremes of tropical rainfall accumulation. While the focus of this work is on annual accumulation over the entire tropics, it is interesting to note that a similar analysis over smaller regions (e.g., continental US) clearly shows that previously reported "trends" in short duration extremes are in fact a subset of this aforementioned ENSO footprint. This hypothesis is verified using high-resolution TRMM rainfall observations during the past two decades. Finally, taking advantage of the temporal resolution afforded by TRMM, the change in extremes is seen to go hand in hand with a progressive increase in variance and intensity, and a

  5. Counselling and management for anticipated extremely preterm birth

    PubMed Central

    Jefferies, Ann L; Kirpalani, Haresh M

    2012-01-01

    Extremely preterm birth (birth between 220/7 and 256/7 weeks’ gestational age [GA]) often requires parents to make complex choices about the care of their infant. Health professionals have a significant role in providing information, guidance and support. Parents facing the birth of an extremely preterm infant should have the chance to meet with both obstetrical and paediatric/neonatal care providers to receive accurate information about their infant’s prognosis, provided with clarity and compassion. Decision making between parents and health professionals should be an informed and shared process, with documentation of all management decisions. Consultation with and transfer to tertiary perinatal centres are important for the care of both mother and fetus. As the survival of infants born before or at 22 completed weeks’ GA remains uncommon, a noninterventional approach is recommended, whereas at 23, 24 and 25 weeks’ GA, counselling about outcomes and decision making should be individualized for each infant and family, using factors which influence prognosis. All extremely preterm infants who are not resuscitated, or for whom resuscitation is not successful, must receive compassionate palliative care. PMID:24082807

  6. Suction is kid's play: extremely fast suction in newborn seahorses.

    PubMed

    Van Wassenbergh, Sam; Roos, Gert; Genbrugge, Annelies; Leysen, Heleen; Aerts, Peter; Adriaens, Dominique; Herrel, Anthony

    2009-04-23

    Ongoing anatomical development typically results in a gradual maturation of the feeding movements from larval to adult fishes. Adult seahorses are known to capture prey by rotating their long-snouted head extremely quickly towards prey, followed by powerful suction. This type of suction is powered by elastic recoil and requires very precise coordination of the movements of the associated feeding structures, making it an all-or-none phenomenon. Here, we show that newborn Hippocampus reidi are able to successfully feed using an extremely rapid and powerful snout rotation combined with a high-volume suction, surpassing that observed in adult seahorses. An inverse dynamic analysis shows that an elastic recoil mechanism is also used to power head rotation in newborn H. reidi. This illustrates how extreme levels of performance in highly complex musculoskeletal systems can be present at birth given a delayed birth and rapid development of functionally important structures. The fact that the head skeleton of newborn seahorses is still largely cartilaginous may not be problematic because the hydrodynamic stress on the rotating snout appeared considerably lower than in adult syngnathids.

  7. Extreme value statistics of cosmic microwave background lensing deflection angles

    NASA Astrophysics Data System (ADS)

    Merkel, Philipp M.; Schäfer, Björn Malte

    2015-10-01

    The smaller the angular scales on which the anisotropies of the cosmic microwave background (CMB) are probed the more important their distortion due to gravitational lensing becomes. Here we investigate the maxima and minima of the CMB lensing deflection field using general extreme value statistics. Since general extreme value statistics applies to uncorrelated data in first place, we consider appropriately low-pass-filtered deflection maps. Besides the suppression of correlations filtering is required for another reason: the lensing field itself is not directly observable but needs to be (statistically) reconstructed from the lensed CMB by means of a quadratic estimator. This reconstruction, though, is noise dominated and therefore requires smoothing too. In idealized Gaussian realizations as well as in realistically reconstructed data, we find that both maxima and minima of the deflection angle components follow consistently a general extreme value distribution of Weibull type. However, its shape, location and scale parameters vary significantly between different realizations. The statistics' potential power to constrain cosmological models appears, therefore, rather limited.

  8. A model for extremely powerful extragalactic water masers

    SciTech Connect

    Wu, Ying-Cheng; Alcock, C.

    1988-08-01

    The reasons for the differences between extremely powerful extragalatic water masers (EPEWMs) and strong Galactic H/sub 2/O masers are discussed. This model quite successfully explains many important characteristics of EPEWMs; the rapid time variations, the broad range and random velocity distribution, the extremely high luminosities, the various heights or widths of features in spectra, the strong infrared radiation from the galaxies, how an active nucleus contributes to an EPEWM, how some parts of EPEWMs producing strong features are pumped, why this pump mechanism can work, and why EPEWMs are different from strong Galactic H/sub 2/O masers. Recent observations of extragalactic water masers which have extremely high luminosities raise the possibility that the stimulated emission rate in the maser emission line in these regions is much higher than in Galactic masers. It is possible that the local stimulated emission rate exceeds the local bandwidth for the radiation. In this case the standard expression relating the photon emission rate to the profile averaged mean intensity does not apply. A new expression for the photon emission rate is derived.

  9. Scenarios of daily extreme precipitation under climate change

    NASA Astrophysics Data System (ADS)

    Michael, Hofstätter; Christoph, Matulla; Jiafeng, Wang

    2010-05-01

    Daily extreme precipitation events under climate change conditions are the focus of research in our study. Such events can have considerable impacts on wealth and society by causing floodings or mudslides for example. In our study we used daily records of precipitation at 50 stations over Austria covering the period 1963-2006. To calculate the adequate timeseries for the future considering IPCC's climate change scenarios A1B and B1, we applied the analog method. Daily fields of Sea Level Pressure from the NCAR/NCEP1 Reanalysis within the region of Europe (20W-35E/30S-65N), served as the prime predictor between local scale observations and climate simulations out of the MPI-ECHAM5 model. Several return values were determined by fitting a GEV distribution to the timeseries consisting of the three most extreme, declustered events per year. The results reveal that future changes of 20y-return values are within +/-20% for most stations, whereby the signal of change is stronger for the first period (2007-2050) as compared to the later one (2051-2094). This is valid for both IPCC scenarios. We conclude, that even in the relatively small area of Austria both the sign and rate of change in future extreme precipitation, offers a clear diversity among climatological regions. This implies an important aspect for forthcoming studies.

  10. Simulating merging binary black holes with nearly extremal spins

    SciTech Connect

    Lovelace, Geoffrey; Scheel, Mark A.; Szilagyi, Bela

    2011-01-15

    Astrophysically realistic black holes may have spins that are nearly extremal (i.e., close to 1 in dimensionless units). Numerical simulations of binary black holes are important tools both for calibrating analytical templates for gravitational-wave detection and for exploring the nonlinear dynamics of curved spacetime. However, all previous simulations of binary-black-hole inspiral, merger, and ringdown have been limited by an apparently insurmountable barrier: the merging holes' spins could not exceed 0.93, which is still a long way from the maximum possible value in terms of the physical effects of the spin. In this paper, we surpass this limit for the first time, opening the way to explore numerically the behavior of merging, nearly extremal black holes. Specifically, using an improved initial-data method suitable for binary black holes with nearly extremal spins, we simulate the inspiral (through 12.5 orbits), merger and ringdown of two equal-mass black holes with equal spins of magnitude 0.95 antialigned with the orbital angular momentum.

  11. Poorest countries experience earlier anthropogenic emergence of daily temperature extremes

    NASA Astrophysics Data System (ADS)

    Harrington, Luke J.; Frame, David J.; Fischer, Erich M.; Hawkins, Ed; Joshi, Manoj; Jones, Chris D.

    2016-05-01

    Understanding how the emergence of the anthropogenic warming signal from the noise of internal variability translates to changes in extreme event occurrence is of crucial societal importance. By utilising simulations of cumulative carbon dioxide (CO2) emissions and temperature changes from eleven earth system models, we demonstrate that the inherently lower internal variability found at tropical latitudes results in large increases in the frequency of extreme daily temperatures (exceedances of the 99.9th percentile derived from pre-industrial climate simulations) occurring much earlier than for mid-to-high latitude regions. Most of the world’s poorest people live at low latitudes, when considering 2010 GDP-PPP per capita; conversely the wealthiest population quintile disproportionately inhabit more variable mid-latitude climates. Consequently, the fraction of the global population in the lowest socio-economic quintile is exposed to substantially more frequent daily temperature extremes after much lower increases in both mean global warming and cumulative CO2 emissions.

  12. Photoresist composition for extreme ultraviolet lithography

    DOEpatents

    Felter, T. E.; Kubiak, G. D.

    1999-01-01

    A method of producing a patterned array of features, in particular, gate apertures, in the size range 0.4-0.05 .mu.m using projection lithography and extreme ultraviolet (EUV) radiation. A high energy laser beam is used to vaporize a target material in order to produce a plasma which in turn, produces extreme ultraviolet radiation of a characteristic wavelength of about 13 nm for lithographic applications. The radiation is transmitted by a series of reflective mirrors to a mask which bears the pattern to be printed. The demagnified focused mask pattern is, in turn, transmitted by means of appropriate optics and in a single exposure, to a substrate coated with photoresists designed to be transparent to EUV radiation and also satisfy conventional processing methods. A photoresist composition for extreme ultraviolet radiation of boron carbide polymers, hydrochlorocarbons and mixtures thereof.

  13. Extreme_SeaState_Contour_v1

    2015-10-19

    This software generates environmental contours of extreme sea states using buoy observations of significant wave height and energy period or peak period. The code transforms these observations using principal component analysis (PCA) to create an uncorrelated representation of the data. The subsequent components are modeled using probability distributions and parameter fitting functions. The inverse first-order reliability method (I-FORM) is then applied to these models in order to generate an extreme event contour based on amore » given return period (i.e., 100 years).The subsequent contour is then transformed back into the original input space defined by the variables of interest in order to create an environmental contour of extreme sea states.« less

  14. Extremism without extremists: Deffuant model with emotions

    NASA Astrophysics Data System (ADS)

    Sobkowicz, Pawel

    2015-03-01

    The frequent occurrence of extremist views in many social contexts, often growing from small minorities to almost total majority, poses a significant challenge for democratic societies. The phenomenon can be described within the sociophysical paradigm. We present a modified version of the continuous bounded confidence opinion model, including a simple description of the influence of emotions on tolerances, and eventually on the evolution of opinions. Allowing for psychologically based correlation between the extreme opinions, high emotions and low tolerance for other people's views leads to quick dominance of the extreme views within the studied model, without introducing a special class of agents, as has been done in previous works. This dominance occurs even if the initial numbers of people with extreme opinions is very small. Possible suggestions related to mitigation of the process are briefly discussed.

  15. Extremes of Population Estimated from Kepler Observations

    NASA Astrophysics Data System (ADS)

    Traub, Wesley A.

    2015-12-01

    The extremes of exoplanet population (0.5 to 16 Earth radii, 0.5 to 512 days period) are estimated from Kepler observations by comparing the observed numbers of planets at each radius and period against a simulation that accounts for the probability of transit and the estimated instrument sensitivity. By assuming that the population can be modeled as a function of period times a function of radius, and further assuming that these functions are broken power laws, sufficient leverage is gained such that the well-measured short-period extreme of the planet distribution can effectively be used as a template for the less-well sampled long-period extreme. The resulting population distribution over this full range of radius and period provides a challenge to models of the origin and evolution of planetary systems.

  16. Extreme_SeaState_Contour_v1

    SciTech Connect

    2015-10-19

    This software generates environmental contours of extreme sea states using buoy observations of significant wave height and energy period or peak period. The code transforms these observations using principal component analysis (PCA) to create an uncorrelated representation of the data. The subsequent components are modeled using probability distributions and parameter fitting functions. The inverse first-order reliability method (I-FORM) is then applied to these models in order to generate an extreme event contour based on a given return period (i.e., 100 years).The subsequent contour is then transformed back into the original input space defined by the variables of interest in order to create an environmental contour of extreme sea states.

  17. Extremal Bundles on Calabi-Yau Threefolds

    NASA Astrophysics Data System (ADS)

    Gao, Peng; He, Yang-Hui; Yau, Shing-Tung

    2015-06-01

    We study constructions of stable holomorphic vector bundles on Calabi-Yau threefolds, especially those with exact anomaly cancellation which we call extremal. By going through the known databases we find that such examples are rare in general and can be ruled out for the spectral cover construction for all elliptic threefolds. We then introduce a general Hartshorne-Serre construction and use it to find extremal bundles of general ranks and study their stability, as well as computing their Chern numbers. Based on both existing and our new constructions, we revisit the DRY conjecture for the existence of stable sheaves on Calabi-threefolds, and provide theoretical and numerical evidence for its correctness. Our construction can be easily generalized to bundles with no extremal conditions imposed.

  18. Microbial communities evolve faster in extreme environments

    PubMed Central

    Li, Sheng-Jin; Hua, Zheng-Shuang; Huang, Li-Nan; Li, Jie; Shi, Su-Hua; Chen, Lin-Xing; Kuang, Jia-Liang; Liu, Jun; Hu, Min; Shu, Wen-Sheng

    2014-01-01

    Evolutionary analysis of microbes at the community level represents a new research avenue linking ecological patterns to evolutionary processes, but remains insufficiently studied. Here we report a relative evolutionary rates (rERs) analysis of microbial communities from six diverse natural environments based on 40 metagenomic samples. We show that the rERs of microbial communities are mainly shaped by environmental conditions, and the microbes inhabiting extreme habitats (acid mine drainage, saline lake and hot spring) evolve faster than those populating benign environments (surface ocean, fresh water and soil). These findings were supported by the observation of more relaxed purifying selection and potentially frequent horizontal gene transfers in communities from extreme habitats. The mechanism of high rERs was proposed as high mutation rates imposed by stressful conditions during the evolutionary processes. This study brings us one stage closer to an understanding of the evolutionary mechanisms underlying the adaptation of microbes to extreme environments. PMID:25158668

  19. A Simultaneous Discovery: The Case of Johannes Stark and Antonino Lo Surdo

    NASA Astrophysics Data System (ADS)

    Leone, Matteo; Paoletti, Alessandro; Robotti, Nadia

    2004-09-01

    In 1913 the German physicist Johannes Stark (1874 1957) and the Italian physicist Antonino Lo Surdo (1880 1949)discovered virtually simultaneously and independently that hydrogen spectral lines are split into components by an external electric field. Both of their discoveries ensued from studies on the same phenomenon, the Doppler effect in canal rays, but they arose in different theoretical contexts. Stark had been working within the context of the emerging quantum theory, following a research program aimed at studying the effect of an electric field on spectral lines. Lo Surdo had been working within the context of the classical theory, and his was an accidental discovery. Both discoveries, however, played important roles in the history of physics: Stark’s discovery contributed to the establishment of both the old and the new quantum theories; Lo Surdo’s discovery led Antonio Garbasso (1871 1933)to introduce research on the quantum theory into Italian physics. Ironically, soon after their discoveries, both Stark and Lo Surdo rejected developments in modern physics and allied themselves with the political and racial programs of Hitler and Mussolini.

  20. Phenotypic extremes in rare variant study designs.

    PubMed

    Peloso, Gina M; Rader, Daniel J; Gabriel, Stacey; Kathiresan, Sekar; Daly, Mark J; Neale, Benjamin M

    2016-06-01

    Currently, next-generation sequencing studies aim to identify rare and low-frequency variation that may contribute to disease. For a given effect size, as the allele frequency decreases, the power to detect genes or variants of interest also decreases. Although many methods have been proposed for the analysis of such data, study design and analytic issues still persist in data interpretation. In this study we present sequencing data for ABCA1 that has known rare variants associated with high-density lipoprotein cholesterol (HDL-C). We contrast empirical findings from two study designs: a phenotypic extreme sample and a population-based random sample. We found differing strengths of association with HDL-C across the two study designs (P=0.0006 with n=701 phenotypic extremes vs P=0.03 with n=1600 randomly sampled individuals). To explore this apparent difference in evidence for association, we performed a simulation study focused on the impact of phenotypic selection on power. We demonstrate that the power gain for an extreme phenotypic selection study design is much greater in rare variant studies than for studies of common variants. Our study confirms that studying phenotypic extremes is critical in rare variant studies because it boosts power in two ways: the typical increases from extreme sampling and increasing the proportion of relevant functional variants ascertained and thereby tested for association. Furthermore, we show that when combining statistical evidence through meta-analysis from an extreme-selected sample and a second separate population-based random sample, power is lower when a traditional sample size weighting is used compared with weighting by the noncentrality parameter. PMID:26350511

  1. Biological Extreme Events - Past, Present, and Future

    NASA Astrophysics Data System (ADS)

    Gutschick, V. P.

    2010-12-01

    Biological extreme events span wide ranges temporally and spatially and in type - population dieoffs, extinctions, ecological reorganizations, changes in biogeochemical fluxes, and more. Driving variables consist in meteorology, tectonics, orbital changes, anthropogenic changes (land-use change, species introductions, reactive N injection into the biosphere), and evolution (esp. of diseases). However, the mapping of extremes in the drivers onto biological extremes as organismal responses is complex, as laid out originally in the theoretical framework of Gutschick and BassiriRad (New Phytologist [2003] 100:21-42). Responses are nonlinear and dependent on (mostly unknown and) complex temporal sequences - often of multiple environmental variables. The responses are species- and genotype specific. I review extreme events over from past to present over wide temporal scales, while noting that they are not wholly informative of responses to the current and near-future drivers for at least two reasons: 1) the current combination of numerous environmental extremes - changes in CO2, temperature, precipitation, reactive N, land fragmentation, O3, etc. -is unprecedented in scope, and 2) adaptive genetic variation for organismal responses is constrained by poorly-characterized genetic structures (in organisms and populations) and by loss of genetic variation by genetic drift over long periods. We may expect radical reorganizations of ecosystem and biogeochemical functions. These changes include many ecosystem services in flood control, crop pollination and insect/disease control, C-water-mineral cycling, and more, as well as direct effects on human health. Predictions of such changes will necessarily be very weak in the critical next few decades, given the great deal of observation, experimentation, and theory construction that will be necessary, on both organisms and drivers. To make the research efforts most effective will require extensive, insightful planning, beginning

  2. WETRAX: WEather Patterns, Cyclone TRAcks and related precipitation EXtremes

    NASA Astrophysics Data System (ADS)

    Hofstätter, Michael; Beck, Christoph; Chimani, Barbara; Ganekind, Manfred; Homan, Markus; Jacobeit, Jucundus; Phillip, Andreas

    2013-04-01

    Excessive large scale (LS) precipitation entails high risk of related flooding and is therefore of particular significance for subsequent infrastructural damage, financial loss or the direct threat of human life. The potential and importance of certain atmospheric cyclone tracks or circulation types for such precipitation events, is well known in the hydro-meteorological community, not least because of the flood events in August 2005 and August 2002 for example. However many important questions remain unanswered in this issue. For example, not enough findings are on hand assessing the relevance of certain circulation types or cyclone track types for large scale precipitation characteristics in Central Europe. In particular changes in the risk of LS extreme precipitation under future climate change conditions due to an altered atmospheric circulation, remain unknown in fact. In this collaborative study repetitive atmospheric patterns as large-scale circulation types and cyclone track types are investigated in terms of their relevance for non-convective extreme precipitation over Southern Germany and Austria. Two different Global Climate Models will be evaluated in their ability to simulate the important atmospheric characteristics under current climate conditions, in order to assess the changing probability of occurrence of extreme precipitation events under future climate conditions. The results of this study will give new insights in the nature of atmospheric cyclones and circulation types as the trigger of large scale precipitation in the study region, hence improving hydro-meteorological knowledge and providing basic essentials for the trans-national water resource management under the aspect of ongoing climate change.

  3. Overview of the biology of extreme events

    NASA Astrophysics Data System (ADS)

    Gutschick, V. P.; Bassirirad, H.

    2008-12-01

    Extreme events have, variously, meteorological origins as in heat waves or precipitation extremes, or biological origins as in pest and disease eruptions (or tectonic, earth-orbital, or impact-body origins). Despite growing recognition that these events are changing in frequency and intensity, a universal model of ecological responses to these events is slow to emerge. Extreme events, negative and positive, contrast with normal events in terms of their effects on the physiology, ecology, and evolution of organisms, hence also on water, carbon, and nutrient cycles. They structure biogeographic ranges and biomes, almost surely more than mean values often used to define biogeography. They are challenging to study for obvious reasons of field-readiness but also because they are defined by sequences of driving variables such as temperature, not point events. As sequences, their statistics (return times, for example) are challenging to develop, as also from the involvement of multiple environmental variables. These statistics are not captured well by climate models. They are expected to change with climate and land-use change but our predictive capacity is currently limited. A number of tools for description and analysis of extreme events are available, if not widely applied to date. Extremes for organisms are defined by their fitness effects on those organisms, and are specific to genotypes, making them major agents of natural selection. There is evidence that effects of extreme events may be concentrated in an extended recovery phase. We review selected events covering ranges of time and magnitude, from Snowball Earth to leaf functional loss in weather events. A number of events, such as the 2003 European heat wave, evidence effects on water and carbon cycles over large regions. Rising CO2 is the recent extreme of note, for its climatic effects and consequences for growing seasons, transpiration, etc., but also directly in its action as a substrate of photosynthesis

  4. Effects of Extreme Climate on Mediterranean Societies

    NASA Astrophysics Data System (ADS)

    Xoplaki, Elena

    2009-04-01

    Climate Extremes During Recent Millennia and Their Impact on Mediterranean Societies; Athens, Greece, 13-16 September 2008; Climatic extremes in the past few thousand years have severely affected societies throughout the Mediterranean region and have changed the outcome of historical events in some instances. Climatic extremes—droughts, floods, prolonged cold and heat—affect society in a variety of ways, operating through famine, disease, and social upheaval. These topics were discussed at an interdisciplinary symposium at the National and Kapodistrian University, in Greece, that brought together climatologists, paleoclimatologists, anthropologists, geologists, archaeologists, and historians working in the greater Mediterranean region.

  5. Overuse lower extremity injuries in sports.

    PubMed

    Fullem, Brian W

    2015-04-01

    When athletes train harder the risk of injury increases, and there are several common overuse injuries to the lower extremity. Three of the most common lower extremity overuse injuries in sports are discussed including the diagnosis and treatments: medial tibal stress syndrome, iliotibial band syndrome, and stress fractures. The charge of sports medicine professionals is to identify and treat the cause of the injuries and not just treat the symptoms. Symptomatology is an excellent guide to healing and often the patient leads the physician to the proper diagnosis through an investigation of the athlete's training program, past injury history, dietary habits, choice of footwear, and training surface. PMID:25804713

  6. Robust, Thin Optical Films for Extreme Environments

    NASA Technical Reports Server (NTRS)

    2006-01-01

    The environment of space presents scientists and engineers with the challenges of a harsh, unforgiving laboratory in which to conduct their scientific research. Solar astronomy and X-ray astronomy are two of the more challenging areas into which NASA scientists delve, as the optics for this high-tech work must be extremely sensitive and accurate, yet also be able to withstand the battering dished out by radiation, extreme temperature swings, and flying debris. Recent NASA work on this rugged equipment has led to the development of a strong, thin film for both space and laboratory use.

  7. Far and extreme ultraviolet astronomy with ORFEUS

    NASA Technical Reports Server (NTRS)

    Kraemer, G.; Barnstedt, J.; Eberhard, N.; Grewing, M.; Gringel, W.; Haas, C.; Kaelble, A.; Kappelmann, N.; Petrik, J.; Appenzeller, I.

    1990-01-01

    ORFEUS (Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer) is a 1 m normal incidence telescope for spectroscopic investigations of cosmic sources in the far and extreme ultraviolet spectral range. The instrument will be integrated into the freeflyer platform ASTRO-SPAS. ORFEUS-SPAS is scheduled with STS ENDEAVOUR in September 1992. We describe the telescope with its two spectrometer and their capabilities i.e., spectral range, resolution and overall sensitivity. The main classes of objects to be observed with the instrument are discussed and two examples of simulated spectra for the white dwarf HZ43 and an O9-star in LMC are shown.

  8. Extreme Science (LBNL Science at the Theater)

    SciTech Connect

    Ajo-Franklin, Caroline; Klein, Spencer; Minor, Andrew; Torok, Tamas

    2012-02-27

    On Feb. 27, 2012 at the Berkeley Repertory Theatre, four Berkeley Lab scientists presented talks related to extreme science - and what it means to you. Topics include: Neutrino hunting in Antarctica. Learn why Spencer Klein goes to the ends of the Earth to search for these ghostly particles. From Chernobyl to Central Asia, Tamas Torok travels the globe to study microbial diversity in extreme environments. Andrew Minor uses the world's most advanced electron microscopes to explore materials at ultrahigh stresses and in harsh environments. And microbes that talk to computers? Caroline Ajo-Franklin is pioneering cellular-electrical connections that could help transform sunlight into fuel.

  9. Electric spaser in the extreme quantum limit.

    PubMed

    Li, Dabing; Stockman, Mark I

    2013-03-01

    We consider theoretically the spaser that is excited electrically via a nanowire with ballistic quantum conductance. We show that, in the extreme quantum regime, i.e., for a single conductance-quantum nanowire, the spaser with a core made of common plasmonic metals, such as silver and gold, is fundamentally possible. For ballistic nanowires with multiple-quanta or nonquantized conductance, the performance of the spaser is enhanced in comparison with the extreme quantum limit. The electrically pumped spaser is promising as an optical source, nanoamplifier, and digital logic device for optoelectronic information processing with a speed of ~100 GHz to ~100 THz. PMID:23521278

  10. Extreme sports: injuries and medical coverage.

    PubMed

    Young, Craig C

    2002-10-01

    Extreme sports (including in-line skating, snowboarding, mountain bicycling, extreme skiing, rock climbing, indoor tackle football, kickboxing, skateboarding, and ultra-endurance racing) are growing in popularity. Often these sports are designed to expose athletes to greater thrills and risks than are found in traditional sporting activities. Despite this increased risk of injury, athletes competing in these sports often have little or no formal medical coverage. This article reviews what is known about this emerging area of sports medicine to assist physicians in preparing for medical coverage of these athletes and their competitions.

  11. From Failure to Symbol of Astronomical Discovery: The Inspiring Story of the Hubble Space Telescope

    NASA Astrophysics Data System (ADS)

    Nota, A.

    2011-06-01

    Hubble was launched in 1990, with great expectations of scientific breakthroughs: determining the distance scale of the universe, detecting planets around stars other than the Sun. The enthusiasm that accompanied a very successful launch was quickly dampened by the realization that something was seriously wrong with the telescope. While the pictures were clearer than those of ground-based telescopes, they were not the pristine images promised. Hubble's mirror had a flaw. It was affected by "spherical aberration". Hubble's images were permanently out of focus. This is where the inspiring part of the story starts: scientists and engineers, in a coordinated effort across continents, pulled together to design the solution. The Corrective Optics Space Telescope Axial Replacement (COSTAR) was installed three years later by a brave crew of astronauts who showed to the world that performing complex tasks in space is possible, and paved the way to the construction of the International Space Station. The first images from Hubble with the new optics were superb. The telescope was all that had been promised and more, and changed the way we think of the universe. Designed to be repaired in space, Hubble has been refurbished four additional times. Every time, critical subsystems such as gyros and batteries are replaced, and its scientific instrument complement is upgraded. The last mission to Hubble (SM4) has been successfully completed in May 2009. Two new instruments have been installed, two existing instruments have been repaired in space, and new scientific results are pouring in. Hubble will continue pushing the boundaries of our knowledge of the universe for years to come. But, more importantly, Hubble has showed that partnership, ingenuity and determination can transform the most devastating failure in a long lasting success.

  12. Free and total thyroid hormones in humans at extreme altitude

    NASA Astrophysics Data System (ADS)

    Basu, Minakshi; Pal, K.; Malhotra, A. S.; Prasad, R.; Sawhney, R. C.

    1995-03-01

    Alterations in circulatory levels of total T4 (TT4), total T3 (TT3), free T4 (FT4), free T3 (FT3), thyrotropin (TSH) and T3 uptake (T3U) were studied in male and female sea-level residents (SLR) at sea level, in Armed forces personnel staying at high altitude (3750 m) for prolonged duration (acclimatized lowlanders, ALL) and in high-altitude natives (HAN). Identical studies were also performed on male ALL who trekked to an extreme altitude of 5080 m and stayed at an altitude of more than 6300 m for about 6 months. The total as well as free thyroid hormones were found to be significantly higher in ALL and HAN as compared to SLR values. Both male as well as female HAN had higher levels of thyroid hormones. The rise in hormone levels in different ALL ethnic groups drawn from amongst the southern and northern parts of the country was more or less identical. In both HAN and ALL a decline in FT3 and FT4 occurred when these subjects trekked at subzero temperatures to extreme altitude of 5080 m but the levels were found to be higher in ALL who stayed at 6300 m for a prolonged duration. Plasma TSH did not show any appreciable change at lower altitudes but was found to be decreased at extreme altitude. The increase in thyroid hormones at high altitude was not due to an increase in hormone binding proteins, since T3U was found to be higher at high altitudes. A decline in TSH and hormone binding proteins and an increase in the free moiety of the hormones is indicative of a subtle degree of tissue hyperthyroidism which may be playing an important role in combating the extreme cold and hypoxic environment of high altitudes.

  13. A fully probabilistic approach to extreme rainfall modeling

    NASA Astrophysics Data System (ADS)

    Coles, Stuart; Pericchi, Luis Raúl; Sisson, Scott

    2003-03-01

    It is an embarrassingly frequent experience that statistical practice fails to foresee historical disasters. It is all too easy to blame global trends or some sort of external intervention, but in this article we argue that statistical methods that do not take comprehensive account of the uncertainties involved in both model and predictions, are bound to produce an over-optimistic appraisal of future extremes that is often contradicted by observed hydrological events. Based on the annual and daily rainfall data on the central coast of Venezuela, different modeling strategies and inference approaches show that the 1999 rainfall which caused the worst environmentally related tragedy in Venezuelan history was extreme, but not implausible given the historical evidence. We follow in turn a classical likelihood and Bayesian approach, arguing that the latter is the most natural approach for taking into account all uncertainties. In each case we emphasize the importance of making inference on predicted levels of the process rather than model parameters. Our most detailed model comprises of seasons with unknown starting points and durations for the extremes of daily rainfall whose behavior is described using a standard threshold model. Based on a Bayesian analysis of this model, so that both prediction uncertainty and process heterogeneity are properly modeled, we find that the 1999 event has a sizeable probability which implies that such an occurrence within a reasonably short time horizon could have been anticipated. Finally, since accumulation of extreme rainfall over several days is an additional difficulty—and indeed, the catastrophe of 1999 was exaggerated by heavy rainfall on successive days—we examine the effect of timescale on our broad conclusions, finding results to be broadly similar across different choices.

  14. Regional Frequency and Uncertainty Analysis of Extreme Precipitation in Bangladesh

    NASA Astrophysics Data System (ADS)

    Mortuza, M. R.; Demissie, Y.; Li, H. Y.

    2014-12-01

    Increased frequency of extreme precipitations, especially those with multiday durations, are responsible for recent urban floods and associated significant losses of lives and infrastructures in Bangladesh. Reliable and routinely updated estimation of the frequency of occurrence of such extreme precipitation events are thus important for developing up-to-date hydraulic structures and stormwater drainage system that can effectively minimize future risk from similar events. In this study, we have updated the intensity-duration-frequency (IDF) curves for Bangladesh using daily precipitation data from 1961 to 2010 and quantified associated uncertainties. Regional frequency analysis based on L-moments is applied on 1-day, 2-day and 5-day annual maximum precipitation series due to its advantages over at-site estimation. The regional frequency approach pools the information from climatologically similar sites to make reliable estimates of quantiles given that the pooling group is homogeneous and of reasonable size. We have used Region of influence (ROI) approach along with homogeneity measure based on L-moments to identify the homogenous pooling groups for each site. Five 3-parameter distributions (i.e., Generalized Logistic, Generalized Extreme value, Generalized Normal, Pearson Type Three, and Generalized Pareto) are used for a thorough selection of appropriate models that fit the sample data. Uncertainties related to the selection of the distributions and historical data are quantified using the Bayesian Model Averaging and Balanced Bootstrap approaches respectively. The results from this study can be used to update the current design and management of hydraulic structures as well as in exploring spatio-temporal variations of extreme precipitation and associated risk.

  15. Multifractal Geophysical Extremes: Nonstationarity and Long Range Correlations

    NASA Astrophysics Data System (ADS)

    Tchiguirinskaia, I.; Schertzer, D.; Lovejoy, S.

    2012-04-01

    Throughout the world, extremes in environmental sciences are of prime importance. They are key variables not only for risk assessments and engineering designs (e.g. of dams and bridges), but also for resource management (e.g. water and energy) and for land use. A better understanding of them is more and more indispensable in settling the debate on their possible climatological evolution. Whereas it took decades before a uniform technique for estimating flow frequencies within a stationary framework, it is often claimed that « stationarity is dead ! ». The fact that geophysical and environmental fields are variable over a wider range of scales than previously thought require to go beyond the limits of the (classical) Extreme Value Theory (EVT). Indeed, long-range correlations are beyond the scope of the classical EVT theory. We show that multifractal concepts and techniques are particularly appealing because they can effectively deal with a cascade of interactions concentrating for instance energy, liquid water, etc. into smaller and smaller space-time domains. Furthermore, a general outcome of these cascade processes -which surprisingly was realized only rather recently- is that rather independently of their details they yield probability distributions with power-law fall-offs, often called (asymptotic) Pareto or Zipf laws. We discuss the corresponding probability distributions of their maxima and its relationship with the Frechet law. We use these multifractal techniques to investigate the possibility of using very short or incomplete data records for reliable statistical predictions of the extremes. In particular we assess the multifractal parameter uncertainty with the help of long synthetic multifractal series and their sub-samples, in particular to obtain an approximation of confidence intervals that would be particularly important for the predictions of multifractal extremes. We finally illustrate the efficiency of this approach with its application to

  16. No Quantum Realization of Extremal No-Signaling Boxes

    NASA Astrophysics Data System (ADS)

    Ramanathan, Ravishankar; Tuziemski, Jan; Horodecki, Michał; Horodecki, Paweł

    2016-07-01

    The study of quantum correlations is important for fundamental reasons as well as for quantum communication and information processing tasks. On the one hand, it is of tremendous interest to derive the correlations produced by measurements on separated composite quantum systems from within the set of all correlations obeying the no-signaling principle of relativity, by means of information-theoretic principles. On the other hand, an important ongoing research program concerns the formulation of device-independent cryptographic protocols based on quantum nonlocal correlations for the generation of secure keys, and the amplification and expansion of random bits against general no-signaling adversaries. In both these research programs, a fundamental question arises: Can any measurements on quantum states realize the correlations present in pure extremal no-signaling boxes? Here, we answer this question in full generality showing that no nontrivial (not local realistic) extremal boxes of general no-signaling theories can be realized in quantum theory. We then explore some important consequences of this fact.

  17. No Quantum Realization of Extremal No-Signaling Boxes.

    PubMed

    Ramanathan, Ravishankar; Tuziemski, Jan; Horodecki, Michał; Horodecki, Paweł

    2016-07-29

    The study of quantum correlations is important for fundamental reasons as well as for quantum communication and information processing tasks. On the one hand, it is of tremendous interest to derive the correlations produced by measurements on separated composite quantum systems from within the set of all correlations obeying the no-signaling principle of relativity, by means of information-theoretic principles. On the other hand, an important ongoing research program concerns the formulation of device-independent cryptographic protocols based on quantum nonlocal correlations for the generation of secure keys, and the amplification and expansion of random bits against general no-signaling adversaries. In both these research programs, a fundamental question arises: Can any measurements on quantum states realize the correlations present in pure extremal no-signaling boxes? Here, we answer this question in full generality showing that no nontrivial (not local realistic) extremal boxes of general no-signaling theories can be realized in quantum theory. We then explore some important consequences of this fact. PMID:27517758

  18. No Quantum Realization of Extremal No-Signaling Boxes.

    PubMed

    Ramanathan, Ravishankar; Tuziemski, Jan; Horodecki, Michał; Horodecki, Paweł

    2016-07-29

    The study of quantum correlations is important for fundamental reasons as well as for quantum communication and information processing tasks. On the one hand, it is of tremendous interest to derive the correlations produced by measurements on separated composite quantum systems from within the set of all correlations obeying the no-signaling principle of relativity, by means of information-theoretic principles. On the other hand, an important ongoing research program concerns the formulation of device-independent cryptographic protocols based on quantum nonlocal correlations for the generation of secure keys, and the amplification and expansion of random bits against general no-signaling adversaries. In both these research programs, a fundamental question arises: Can any measurements on quantum states realize the correlations present in pure extremal no-signaling boxes? Here, we answer this question in full generality showing that no nontrivial (not local realistic) extremal boxes of general no-signaling theories can be realized in quantum theory. We then explore some important consequences of this fact.

  19. Electrodiagnosis of brachial plexopathies and proximal upper extremity neuropathies.

    PubMed

    Simmons, Zachary

    2013-02-01

    This article describes the normal anatomy of the brachial plexus and its major terminal branches, as well as the major causes and clinical presentations of lesions of these structures. An approach to electrodiagnosis of brachial plexopathies and proximal upper extremity neuropathies is provided, with an emphasis on those nerve conduction studies and portions of the needle examination, which permit localization of lesions to specific trunks, cords, and terminal branches. The importance of specific sensory nerve conduction studies for differentiating plexopathies from radiculopathies and mononeuropathies is emphasized.

  20. Case Histories of Four Extremely Intense Rockbursts in Deep Tunnels

    NASA Astrophysics Data System (ADS)

    Zhang, Chuanqing; Feng, Xia-Ting; Zhou, Hui; Qiu, Shili; Wu, Wenping

    2012-05-01

    In the process of excavating seven parallel tunnels at the Jinping II Hydropower Station, several extremely intense rockbursts occurred, killing and injuring construction workers and damaging several sets of equipment. Based on the characteristics and mechanisms of these rockbursts, four typical events were selected and their temporal and spatial characteristics were here described in detail. The geological conditions revealed after the rockbursts were surveyed carefully. The responses of support elements were also analyzed. The details documented in each case provide not only an important reference for understanding the development mechanisms of rockbursts but also a basis for the selection and development of rockburst prevention measures in deep hard rock tunnels.

  1. Autism spectrum disorders in survivors of extreme prematurity.

    PubMed

    Limperopoulos, Catherine

    2009-12-01

    Recent studies in survivors of extreme prematurity point to an increased prevalence of a previously underrecognized atypical social-behavioral profile strongly suggestive of an autism spectrum disorder. Prospective studies that incorporate early autism screening and autism diagnostic testing are needed to better delineate the sensitivity and specificity of early signs of autism in ex-premature children. Advances in neonatal MRI techniques capable of quantitative structural and functional measurements will also provide important insights into the effects of prematurity itself, and prematurity-related brain injury on the genesis of autism spectrum disorders in this population. Available evidence linking prematurity and autism spectrum disorders is reviewed in this article.

  2. Genomics of an extreme psychrophile, Psychromonas ingrahamii

    SciTech Connect

    Riley, Monica; Staley, James T.; Danchin, Antoine; Wang, T.; Brettin, Tom; Hauser, Loren John; Land, Miriam L; Thompson, Linda S

    2008-05-01

    Background: The genome sequence of the sea-ice bacterium Psychromonas ingrahamii 37, which grows exponentially at -12C, may reveal features that help to explain how this extreme psychrophile is able to grow at such low temperatures. Determination of the whole genome sequence allows comparison with genes of other psychrophiles and mesophiles. Results: Correspondence analysis of the composition of all P. ingrahamii proteins showed that (1) there are 6 classes of proteins, at least one more than other bacteria, (2) integral inner membrane proteins are not sharply separated from bulk proteins suggesting that, overall, they may have a lower hydrophobic character, and (3) there is strong opposition between asparagine and the oxygen-sensitive amino acids methionine, arginine, cysteine and histidine and (4) one of the previously unseen clusters of proteins has a high proportion of "orphan" hypothetical proteins, raising the possibility these are cold-specific proteins. Based on annotation of proteins by sequence similarity, (1) P. ingrahamii has a large number (61) of regulators of cyclic GDP, suggesting that this bacterium produces an extracellular polysaccharide that may help sequester water or lower the freezing point in the vicinity of the cell. (2) P. ingrahamii has genes for production of the osmolyte, betaine choline, which may balance the osmotic pressure as sea ice freezes. (3) P. ingrahamii has a large number (11) of three-subunit TRAP systems that may play an important role in the transport of nutrients into the cell at low temperatures. (4) Chaperones and stress proteins may play a critical role in transforming nascent polypeptides into 3-dimensional configurations that permit low temperature growth. (5) Metabolic properties of P. ingrahamii were deduced. Finally, a few small sets of proteins of unknown function which may play a role in psychrophily have been singled out as worthy of future study. Conclusion: The results of this genomic analysis provide a

  3. Delirium: is sleep important?

    PubMed

    Watson, Paula L; Ceriana, Piero; Fanfulla, Francesco

    2012-09-01

    Delirium and poor sleep quality are common and often co-exist in hospitalised patients. A link between these disorders has been hypothesised but whether this link is a cause-and-effect relationship or simply an association resulting from shared mechanisms is yet to be determined. Potential shared mechanisms include: abnormalities of neurotransmitters, tissue ischaemia, inflammation and sedative exposure. Sedatives, while decreasing sleep latency, often cause a decrease in slow wave sleep and stage rapid eye movement (REM) sleep and therefore may not provide the same restorative properties as natural sleep. Mechanical ventilation, an important cause of sleep disruption in intensive care unit (ICU) patients, may lead to sleep disruption not only from the discomfort of the endotracheal tube but also as a result of ineffective respiratory efforts and by inducing central apnoea events if not properly adjusted for the patient's physiologic needs. When possible, efforts should be made to optimise the patient-ventilator interaction to minimise sleep disruptions.

  4. The importance of Spratling.

    PubMed

    Fine, E J; Fine, D L; Sentz, L

    1994-01-01

    William P. Spratling made important contributions to American epileptology at the beginning of this century. He was the first medical superintendent of Craig Colony for Epileptics from 1893 to 1908, cofounder and president of the National Association for the Study of Epilepsy, and first editor of its scholarly journal, Transactions. During his tenure at Craig Colony, Spratling established standards for safe and humane public care of epileptics. He started the first American residency training program emphasizing epileptology. Spratling conducted the first American multicenter research on the causes of death in epilepsy. The dosage of bromide therapy, which he empirically determined, remains correct. In his book Epilepsy and Its Treatment, Spratling substantiated the cortical origin theory of epilepsy developed by Jackson and Gowers. He was the first American to postulate and investigate a biochemical etiology of generalized seizures in the absence of anatomic lesions. Despite signal accomplishments, his untimely, tragic death may explain why he remains obscure.

  5. Extreme Convective Weather in Future Decades

    NASA Astrophysics Data System (ADS)

    Gadian, Alan; Burton, Ralph; Groves, James; Blyth, Alan; Warner, James; Holland, Greg; Bruyere, Cindy; Done, James; Thielen, Jutta

    2016-04-01

    WISER (Weather Climate Change Impact Study at Extreme Resolution) is a project designed to analyse changes in extreme weather events in a future climate, using a weather model (WRF) which is able to resolve small scale processes. Use of a weather model is specifically designed to look at convection which is of a scale which cannot be resolved by climate models. The regional meso-scale precipitation events, which are critical in understanding climate change impacts will be analysed. A channel domain outer model, with a resolution of ~ 20km in the outer domain drives an inner domain of ~ 3 km resolution. Results from 1989-1994 and 2020-2024 and 2030-2034 will be presented to show the effects of extreme convective events over Western Europe. This presentation will provide details of the project. It will present data from the 1989-1994 ERA-interim and CCSM driven simulations, with analysis of the future years as defined above. The representation of pdfs of extreme precipitation, Outgoing Longwave Radiation and wind speeds, with preliminary comparison with observations will be discussed. It is also planned to use the output to drive the EFAS (European Flood model) to examine the predicted changes in quantity and frequency of severe and hazardous convective rainfall events and leading to the frequency of flash flooding due to heavy convective precipitation.

  6. Propulsion IVHM Extreme Environment Instrumentation Power IVHM

    NASA Technical Reports Server (NTRS)

    Zakrajsek, June

    2000-01-01

    This paper presents propulsion and instrumentation power for integrated vehicle health management technologies. The topics include: 1) Propulsion IVHM Capabilities Research; 2) Projects: X-33 Post-Test Diagnostic System; 3) X-34 NITEX; 4) Advanced Health Monitoring Systems; 5) Active Vibration Monitoring System; 6) Smart Self Healing Propulsion Systems; 7) Extreme Environment Sensors; and 8) Systems Engineering and Integration.

  7. Multiscale Measurement of Extreme Response Style

    ERIC Educational Resources Information Center

    Bolt, Daniel M.; Newton, Joseph R.

    2011-01-01

    This article extends a methodological approach considered by Bolt and Johnson for the measurement and control of extreme response style (ERS) to the analysis of rating data from multiple scales. Specifically, it is shown how the simultaneous analysis of item responses across scales allows for more accurate identification of ERS, and more effective…

  8. Global warming and extreme storm surges

    NASA Astrophysics Data System (ADS)

    Grinsted, Aslak

    2013-04-01

    I will show empirical evidence for how global warming has changed extreme storm surge statistics for different regions in the world. Are there any detectable changes beyond what we expect from sea level rise. What does this suggest about the future of hurricane surges such as from hurricane Katrina and superstorm Sandy?

  9. Extremely Luminous Far-infrared Sources (ELFS)

    NASA Technical Reports Server (NTRS)

    Harwit, Martin; Houck, James R.; Soifer, B. Thomas; Palumbo, Giorgio G. C.

    1987-01-01

    The Infrared Astronomical Satellite (IRAS) survey uncovered a class of Extremely Luminous Far Infrared Sources (ELFS), exhibiting luminosities up to and occasionally exceeding 10 to the 12th power L sub 0. Arguments are presented to show that sources with luminosities L equal to or greater than 3 x 10 to the 10th power L sub 0 may represent gas rich galaxies in collision. The more conventional explanation of these sources as sites of extremely active star formation fails to explain the observed low optical luminosities of ELFS as well as their high infrared excess. In contrast, a collisional model heats gas to a temperature of approx. 10 to the 6th power K where cooling takes place in the extreme ultraviolet. The UV is absorbed by dust and converted into far infrared radiation (FIR) without generation of appreciable optical luminosity. Gas recombination as it cools generates a Lyman alpha photon only once for every two extreme ultraviolet approx. 50eV photons emitted by the 10 to the 6th power gas. That accounts for the high infrared excess. Finally, the model also is able to explain the observed luminosity distribution of ELFS as well as many other traits.

  10. 8 CFR 1240.58 - Extreme hardship.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Extreme hardship. 1240.58 Section 1240.58 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Suspension of Deportation...

  11. 8 CFR 1240.58 - Extreme hardship.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Extreme hardship. 1240.58 Section 1240.58 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Suspension of Deportation...

  12. 8 CFR 1240.58 - Extreme hardship.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Extreme hardship. 1240.58 Section 1240.58 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Suspension of Deportation...

  13. 8 CFR 1240.58 - Extreme hardship.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Extreme hardship. 1240.58 Section 1240.58 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Suspension of Deportation...

  14. 8 CFR 1240.58 - Extreme hardship.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Extreme hardship. 1240.58 Section 1240.58 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS PROCEEDINGS TO DETERMINE REMOVABILITY OF ALIENS IN THE UNITED STATES Suspension of Deportation...

  15. "Extreme Bold" in the Faculty Ranks

    ERIC Educational Resources Information Center

    Kuusisto, Stephen

    2013-01-01

    Boldness, defense, and the necessity of talking back remain as central to life with disability in one's time as in Francis Bacon's age. "Therefore all deformed persons are extreme bold," Bacon wrote, "first, as in their own defence, as being exposed to scorn, but in process of time, by a general habit." Perhaps no word carries more weight in the…

  16. "REsilience," Violent Extremism and Religious Education

    ERIC Educational Resources Information Center

    Miller, Joyce

    2013-01-01

    This article is an attempt to provide an educational justification for the British Government-funded project, "REsilience," on addressing contentious issues through religious education (RE) which was carried out by the RE Council of England and Wales. A number of issues relating to the inclusion of religiously inspired violent extremism in the…

  17. Surface atmospheric extremes (launch and transportation areas)

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Criteria are provided on atmospheric extremes from the surface to 150 meters for geographical locations of interest to NASA. Thermal parameters (temperature and solar radiation), humidity, precipitation, pressure, and atmospheric electricity (lightning and static) are presented. Available data are also provided for the entire continental United States for use in future space programs.

  18. Investigating Extreme Lifestyles through Mangrove Transcriptomics

    ERIC Educational Resources Information Center

    Dassanayake, Maheshi

    2009-01-01

    Mangroves represent phylogenetically diverse taxa in tropical coastal terrestrial habitats. They are extremophiles, evolutionarily adapted to tolerate flooding, anoxia, high temperatures, wind, and high and extremely variable salt conditions in typically resource-poor environments. The genetic basis for these adaptations is, however, virtually…

  19. Security, Extremism and Education: Safeguarding or Surveillance?

    ERIC Educational Resources Information Center

    Davies, Lynn

    2016-01-01

    This article analyses how education is positioned in the current concerns about security and extremism. This means firstly examining the different meanings of security (national, human and societal) and who provides security for whom. Initially, a central dilemma is acknowledged: that schooling appears to be simultaneously irrelevant to the huge…

  20. Extremal surfaces in de Sitter spacetime

    NASA Astrophysics Data System (ADS)

    Narayan, K.

    2015-06-01

    We study extremal surfaces in de Sitter space in the Poincare slicing in the upper patch, anchored on spatial subregions at the future boundary I+, restricted to constant boundary Euclidean time slices (focusing on strip subregions). We find real extremal surfaces of minimal area as the boundaries of past light-cone wedges of the subregions in question: these are null surfaces with vanishing area. We also find complex extremal surfaces as complex extrema of the area functional, and the area is not always real valued. In dS4 the area is real. The area has structural resemblance with entanglement entropy in a dual conformal field theory. There are parallels with analytic continuation from the Ryu-Takayanagi expressions for holographic entanglement entropy in anti-de Sitter. We also discuss extremal surfaces in the de Sitter (dS) black brane and the de Sitter "bluewall" studied previously. The dS4 black brane complex surfaces exhibit a real finite cutoff-independent extensive piece. In the bluewall geometry, there are real surfaces that go from one asymptotic universe to the other through the Cauchy horizons.

  1. Historical influence of irrigation on climate extremes

    NASA Astrophysics Data System (ADS)

    Thiery, Wim; Davin, Edouard L.; Lawrence, Dave; Hauser, Mathias; Seneviratne, Sonia I.

    2016-04-01

    Land irrigation is an essential practice sustaining global food production and many regional economies. During the last decades, irrigation amounts have been growing rapidly. Emerging scientific evidence indicates that land irrigation substantially affects mean climate conditions in different regions of the world. However, a thorough understanding of the impact of irrigation on extreme climatic conditions, such as heat waves, droughts or intense precipitation, is currently still lacking. In this context, we aim to assess the historical influence of irrigation on the occurrence of climate extremes. To this end, two simulations are conducted over the period 1910-2010 with a state-of-the-art global climate model (the Community Earth System Model, CESM): a control simulation including all major anthropogenic and natural external forcings except for irrigation and a second experiment with transient irrigation enabled. The two simulations are evaluated for their ability to represent (i) hot, dry and wet extremes using the HadEX2 and ERA-Interim datasets as a reference, and (ii) latent heat fluxes using LandFlux-EVAL. Assuming a linear combination of climatic responses to different forcings, the difference between both experiments approximates the influence of irrigation. We will analyse the impact of irrigation on a number of climate indices reflecting the intensity and duration of heat waves. Thereby, particular attention is given to the role of soil moisture changes in modulating climate extremes. Furthermore, the contribution of individual biogeophysical processes to the total impact of irrigation on hot extremes is quantified by application of a surface energy balance decomposition technique to the 90th and 99th percentile surface temperature changes.

  2. Microhabitats reduce animal's exposure to climate extremes.

    PubMed

    Scheffers, Brett R; Edwards, David P; Diesmos, Arvin; Williams, Stephen E; Evans, Theodore A

    2014-02-01

    Extreme weather events, such as unusually hot or dry conditions, can cause death by exceeding physiological limits, and so cause loss of population. Survival will depend on whether or not susceptible organisms can find refuges that buffer extreme conditions. Microhabitats offer different microclimates to those found within the wider ecosystem, but do these microhabitats effectively buffer extreme climate events relative to the physiological requirements of the animals that frequent them? We collected temperature data from four common microhabitats (soil, tree holes, epiphytes, and vegetation) located from the ground to canopy in primary rainforests in the Philippines. Ambient temperatures were monitored from outside of each microhabitat and from the upper forest canopy, which represent our macrohabitat controls. We measured the critical thermal maxima (CTmax ) of frog and lizard species, which are thermally sensitive and inhabit our microhabitats. Microhabitats reduced mean temperature by 1-2 °C and reduced the duration of extreme temperature exposure by 14-31 times. Microhabitat temperatures were below the CTmax of inhabitant frogs and lizards, whereas macrohabitats consistently contained lethal temperatures. Microhabitat temperatures increased by 0.11-0.66 °C for every 1 °C increase in macrohabitat temperature, and this nonuniformity in temperature change influenced our forecasts of vulnerability for animal communities under climate change. Assuming uniform increases of 6 °C, microhabitats decreased the vulnerability of communities by up to 32-fold, whereas under nonuniform increases of 0.66 to 3.96 °C, microhabitats decreased the vulnerability of communities by up to 108-fold. Microhabitats have extraordinary potential to buffer climate and likely reduce mortality during extreme climate events. These results suggest that predicted changes in distribution due to mortality and habitat shifts that are derived from macroclimatic samples and that assume

  3. Extreme Geohazards: Reducing the Disaster Risk and Increasing Resilience

    NASA Astrophysics Data System (ADS)

    Plag, Hans-Peter; Stein, Seth; Brocklebank, Sean; Jules-Plag, Shelley; Marsh, Stuart; Campus, Paola

    2013-04-01

    knowledge, particularly during the early warning phase, can reduce disasters. This suggests that a strong global monitoring system for geohazards is needed, not least to support the early detection of extreme hazards. Secondly, low risk awareness combined with poverty, corruption, and a lack of building codes and informed land use management creates the conditions to turn hazards into disasters throughout much of the developing world. Democratizing knowledge about extreme geohazards is very important in order to inform deliberations of disaster risks and community strategies that can reduce the disaster risk by increasing resilience and adaptive capacities without compromising the livelihood of communities. We use a four-order scheme to define disaster risk outcomes and associated societal processes. This framework can be implemented in the context of deliberative democracy and governance with participation of the community. The current dialog between science and society is not fully capable of supporting deliberative governance and a democratizing of knowledge. Most scientific knowledge is created independent of those who could put it to use, and a transition to co-design and co-development of knowledge involving a broad stakeholder base is necessary to address the disaster risk associated with extreme events. This transition may have the consequence of more responsibility and even liability for science.

  4. Core Noise - Increasing Importance

    NASA Technical Reports Server (NTRS)

    Hultgren, Lennart S.

    2011-01-01

    This presentation is a technical summary of and outlook for NASA-internal and NASA-sponsored external research on core (combustor and turbine) noise funded by the Fundamental Aeronautics Program Subsonic Fixed Wing (SFW) Project. Sections of the presentation cover: the SFW system-level noise metrics for the 2015, 2020, and 2025 timeframes; turbofan design trends and their aeroacoustic implications; the emerging importance of core noise and its relevance to the SFW Reduced-Perceived-Noise Technical Challenge; and the current research activities in the core-noise area, with additional details given about the development of a high-fidelity combustor-noise prediction capability as well as activities supporting the development of improved reduced-order, physics-based models for combustor-noise prediction. The need for benchmark data for validation of high-fidelity and modeling work and the value of a potential future diagnostic facility for testing of core-noise-reduction concepts are indicated. The NASA Fundamental Aeronautics Program has the principal objective of overcoming today's national challenges in air transportation. The SFW Reduced-Perceived-Noise Technical Challenge aims to develop concepts and technologies to dramatically reduce the perceived aircraft noise outside of airport boundaries. This reduction of aircraft noise is critical to enabling the anticipated large increase in future air traffic. Noise generated in the jet engine core, by sources such as the compressor, combustor, and turbine, can be a significant contribution to the overall noise signature at low-power conditions, typical of approach flight. At high engine power during takeoff, jet and fan noise have traditionally dominated over core noise. However, current design trends and expected technological advances in engine-cycle design as well as noise-reduction methods are likely to reduce non-core noise even at engine-power points higher than approach. In addition, future low-emission combustor

  5. Educating against Extremism: Towards a Critical Politicisation of Young People

    ERIC Educational Resources Information Center

    Davies, Lynn

    2009-01-01

    This paper is based on a recently published book, "Educating Against Extremism" (Davies, "Educating Against Extremism," 2008), which explores the potential role of schools in averting the more negative and violent forms of extremism in a country. It examines the nature of extremism; identity formation and radicalisation; religious belief, faith…

  6. Extreme sexual behavior in dementia as a specific manifestation of disinhibition.

    PubMed

    Bartelet, Marjukka; Waterink, Wim; van Hooren, Susan

    2014-01-01

    In nursing homes, extreme sexual behavior is one of the most challenging behaviors in dementia. Despite this, however, there is no conformity in the literature regarding how to label and define this type of behavior. Examples of labels used include inappropriate sexual behavior, improper sexual behavior, sexually disinhibited behavior, or hyper sexuality. According to recent theoretical perspectives, extreme sexual behavior may be regarded as a part of disinhibited behavior or could be considered as an independent neuropsychiatric symptom. In this multicenter study, it was investigated whether there is a relationship between extreme sexual behavior and the typical neuropsychiatric symptoms seen in dementia. In 179 residents diagnosed with dementia, extreme sexual behavior was measured using an observation scale. Twelve neuropsychiatric symptoms were measured by the Neuropsychiatric Inventory. Multivariate analysis of covariance with gender showed that residents with observed extreme sexual behavior (n = 43) only showed a higher score on neuropsychiatric symptom 'disinhibition', as compared to residents with non-observed sexual behavior (n = 136). In addition, the effect size was large. These findings indicate that among residents with dementia, extreme sexual behaviors should not be considered as an independent neuropsychiatric symptom. Instead, disinhibition may be an important underlying mechanism for extreme sexual behavior and thus validates the label 'sexually disinhibited behavior'.

  7. A new index quantifying the precipitation extremes

    NASA Astrophysics Data System (ADS)

    Busuioc, Aristita; Baciu, Madalina; Stoica, Cerasela

    2015-04-01

    Events of extreme precipitation have a great impact on society. They are associated with flooding, erosion and landslides.Various indices have been proposed to quantify these extreme events and they are mainly related to daily precipitation amount, which are usually available for long periods in many places over the world. The climate signal related to changes in the characteristics of precipitation extremes is different over various regions and it is dependent on the season and the index used to quantify the precipitation extremes. The climate model simulations and empirical evidence suggest that warmer climates, due to increased water vapour, lead to more intense precipitation events, even when the total annual precipitation is slightly reduced. It was suggested that there is a shift in the nature of precipitation events towards more intense and less frequent rains and increases in heavy rains are expected to occur in most places, even when the mean precipitation is not increasing. This conclusion was also proved for the Romanian territory in a recent study, showing a significant increasing trend of the rain shower frequency in the warm season over the entire country, despite no significant changes in the seasonal amount and the daily extremes. The shower events counted in that paper refer to all convective rains, including torrential ones giving high rainfall amount in very short time. The problem is to find an appropriate index to quantify such events in terms of their highest intensity in order to extract the maximum climate signal. In the present paper, a new index is proposed to quantify the maximum precipitation intensity in an extreme precipitation event, which could be directly related to the torrential rain intensity. This index is tested at nine Romanian stations (representing various physical-geographical conditions) and it is based on the continuous rainfall records derived from the graphical registrations (pluviograms) available at National

  8. [Important issues of biological safety].

    PubMed

    Onishchenko, G G

    2007-01-01

    The problem of biological security raises alarm due to the real growth of biological threats. Biological security includes a wide scope of problems, the solution of which becomes a part of national security as a necessary condition for the constant development of the country. A number of pathogens, such as human immunodeficiency virus, exotic Ebola and Lassa viruses causing hemorrhagic fever,rotaviruses causing acute intestinal diseases, etc. were first discovered in the last century. Terrorist actions committed in the USA in 2001 using the anthrax pathogen made the problem of biological danger even more important. In Russian Federation, biological threats are counteracted through the united state policy being a part of general state security policy. The biological Security legislation of Russian Federation is chiefly based on the 1992 Federal Law on Security. On the basis of cumulated experience, the President of Russia ratified Basics of Russian Federation's State Policy for Chemical and Biological Security for the Period through 2010 and Beyond on 4 December, 2003. The document determines the main directions and stages of the state development in the area of chemical and biological security. The Federal target program Russian Federation's National Program for Chemical and Biological Security is being developed, and its development is to be completed soon in order to perfect the national system for biological security and fulfill Basics of Russian Federation's State Policy for Chemical and Biological Security for the Period through 2010 and Beyond, ratified by the President. The new global strategy for control over infectious diseases, presented in the materials of Saint Petersburg summit of the Group of Eight, as well as the substantive part of its elements in Sanitary International Standards, are to a large degree an acknowledgement of the Russian Federation's experience and the algorithm for fighting extremely dangerous infections. This Russia's experience has

  9. [Important issues of biological safety].

    PubMed

    Onishchenko, G G

    2007-01-01

    The problem of biological security raises alarm due to the real growth of biological threats. Biological security includes a wide scope of problems, the solution of which becomes a part of national security as a necessary condition for the constant development of the country. A number of pathogens, such as human immunodeficiency virus, exotic Ebola and Lassa viruses causing hemorrhagic fever,rotaviruses causing acute intestinal diseases, etc. were first discovered in the last century. Terrorist actions committed in the USA in 2001 using the anthrax pathogen made the problem of biological danger even more important. In Russian Federation, biological threats are counteracted through the united state policy being a part of general state security policy. The biological Security legislation of Russian Federation is chiefly based on the 1992 Federal Law on Security. On the basis of cumulated experience, the President of Russia ratified Basics of Russian Federation's State Policy for Chemical and Biological Security for the Period through 2010 and Beyond on 4 December, 2003. The document determines the main directions and stages of the state development in the area of chemical and biological security. The Federal target program Russian Federation's National Program for Chemical and Biological Security is being developed, and its development is to be completed soon in order to perfect the national system for biological security and fulfill Basics of Russian Federation's State Policy for Chemical and Biological Security for the Period through 2010 and Beyond, ratified by the President. The new global strategy for control over infectious diseases, presented in the materials of Saint Petersburg summit of the Group of Eight, as well as the substantive part of its elements in Sanitary International Standards, are to a large degree an acknowledgement of the Russian Federation's experience and the algorithm for fighting extremely dangerous infections. This Russia's experience has

  10. Generation of multivariate near shore extreme wave conditions based on an extreme value copula for offshore boundary conditions.

    NASA Astrophysics Data System (ADS)

    Leyssen, Gert; Mercelis, Peter; De Schoesitter, Philippe; Blanckaert, Joris

    2013-04-01

    Near shore extreme wave conditions, used as input for numerical wave agitation simulations and for the dimensioning of coastal defense structures, need to be determined at a harbour entrance situated at the French North Sea coast. To obtain significant wave heights, the numerical wave model SWAN has been used. A multivariate approach was used to account for the joint probabilities. Considered variables are: wind velocity and direction, water level and significant offshore wave height and wave period. In a first step a univariate extreme value distribution has been determined for the main variables. By means of a technique based on the mean excess function, an appropriate member of the GPD is selected. An optimal threshold for peak over threshold selection is determined by maximum likelihood optimization. Next, the joint dependency structure for the primary random variables is modeled by an extreme value copula. Eventually the multivariate domain of variables was stratified in different classes, each of which representing a combination of variable quantiles with a joint probability, which are used for model simulation. The main variable is the wind velocity, as in the area of concern extreme wave conditions are wind driven. The analysis is repeated for 9 different wind directions. The secondary variable is water level. In shallow waters extreme waves will be directly affected by water depth. Hence the joint probability of occurrence for water level and wave height is of major importance for design of coastal defense structures. Wind velocity and water levels are only dependent for some wind directions (wind induced setup). Dependent directions are detected using a Kendall and Spearman test and appeared to be those with the longest fetch. For these directions, wind velocity and water level extreme value distributions are multivariately linked through a Gumbel Copula. These distributions are stratified into classes of which the frequency of occurrence can be

  11. Importance of Nuclear Physics to NASA's Space Missions

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Wilson, J. W.; Cucinotta, F. A.

    2001-01-01

    We show that nuclear physics is extremely important for accurate risk assessments for space missions. Due to paucity of experimental input radiation interaction information it is imperative to develop reliable accurate models for the interaction of radiation with matter. State-of-the-art nuclear cross sections models have been developed at the NASA Langley Research center and are discussed.

  12. Excerpts from "The Lewis and Clark Journals: An Epic of Discovery, the Abridgment of the Definitive Nebraska Edition": The Journey across the Plains

    ERIC Educational Resources Information Center

    Moulton, Gary E.

    2003-01-01

    This article contains excerpts from "The Lewis and Clark Journals: An Epic of Discovery, The Abridgment of the Definitive Nebraska Edition," published by the University of Nebraska Press in 2003. Editor Gary E. Moulton chose a few daily entries from the journals to highlight the expedition from May 14-October 12, 1804.

  13. Reducing Waste in Extreme Scale Systems through Introspective Analysis

    SciTech Connect

    Bautista-Gomez, Leonardo; Gainaru, Ana; Perarnau, Swann; Engelmann, Christian; Cappello, Franck; Snir, Marc

    2016-01-01

    Resilience is an important challenge for extreme- scale supercomputers. Today, failures in supercomputers are assumed to be uniformly distributed in time. However, recent studies show that failures in high-performance computing systems are partially correlated in time, generating periods of higher failure density. Our study of the failure logs of multiple supercomputers show that periods of higher failure density occur with up to three times more than the average. We design a monitoring system that listens to hardware events and forwards important events to the runtime to detect those regime changes. We implement a runtime capable of receiving notifications and adapt dynamically. In addition, we build an analytical model to predict the gains that such dynamic approach could achieve. We demonstrate that in some systems, our approach can reduce the wasted time by over 30%.

  14. Analysis of spatial variability of extreme rainfall at radar subpixel scale using IDF curves

    NASA Astrophysics Data System (ADS)

    Peleg, Nadav; Marra, Francesco; Fatichi, Simone; Paschalis, Athanasios; Molnar, Peter; Burlando, Paolo

    2016-04-01

    Extreme rainfall is quantified in engineering practice using Intensity-Duration-Frequency curves (IDFs) that are traditionally derived from rain-gauges and, more recently, also from weather radars. These instruments measure rainfall at different spatial scales: rain-gauge samples rainfall at the point scale while weather radar averages precipitation over a relatively large area, generally around 1 km2. As such, a radar derived IDF curve is representative of the mean areal rainfall over a given radar pixel and neglects the within-pixel rainfall variability. In this study, we quantify subpixel variability of extreme rainfall by using a novel space-time rainfall generator (STREAP model) that downscales in space the rainfall within a given radar pixel. The study was conducted using a long radar data record (23 years) and a very dense rain-gauge network in the Eastern Mediterranean area. Radar-IDF curves, together with an ensemble of point-based IDF curves representing the radar subpixel extreme rainfall variability, were developed fitting GEV distributions to annual rainfall maxima. It was found that the mean areal extreme rainfall derived from the radar underestimate most of the extreme values computed for point locations within the radar pixel. The subpixel variability of extreme rainfall was found to increase with longer return periods and shorter durations. For the longer return periods, a considerable enhancement of extreme rainfall variability was found when stochastic (natural) climate variability was taken into account. Bounding the range of the subpixel extreme rainfall derived from radar-IDF can be of major importance for applications that require very local estimates of rainfall extremes.

  15. Probabilistic forecasting of extreme weather events based on extreme value theory

    NASA Astrophysics Data System (ADS)

    Van De Vyver, Hans; Van Schaeybroeck, Bert

    2016-04-01

    Extreme events in weather and climate such as high wind gusts, heavy precipitation or extreme temperatures are commonly associated with high impacts on both environment and society. Forecasting extreme weather events is difficult, and very high-resolution models are needed to describe explicitly extreme weather phenomena. A prediction system for such events should therefore preferably be probabilistic in nature. Probabilistic forecasts and state estimations are nowadays common in the numerical weather prediction community. In this work, we develop a new probabilistic framework based on extreme value theory that aims to provide early warnings up to several days in advance. We consider the combined events when an observation variable Y (for instance wind speed) exceeds a high threshold y and its corresponding deterministic forecasts X also exceeds a high forecast threshold y. More specifically two problems are addressed:} We consider pairs (X,Y) of extreme events where X represents a deterministic forecast, and Y the observation variable (for instance wind speed). More specifically two problems are addressed: Given a high forecast X=x_0, what is the probability that Y>y? In other words: provide inference on the conditional probability: [ Pr{Y>y|X=x_0}. ] Given a probabilistic model for Problem 1, what is the impact on the verification analysis of extreme events. These problems can be solved with bivariate extremes (Coles, 2001), and the verification analysis in (Ferro, 2007). We apply the Ramos and Ledford (2009) parametric model for bivariate tail estimation of the pair (X,Y). The model accommodates different types of extremal dependence and asymmetry within a parsimonious representation. Results are presented using the ensemble reforecast system of the European Centre of Weather Forecasts (Hagedorn, 2008). Coles, S. (2001) An Introduction to Statistical modelling of Extreme Values. Springer-Verlag.Ferro, C.A.T. (2007) A probability model for verifying deterministic

  16. Important from the Fellows Committee

    NASA Astrophysics Data System (ADS)

    The Union Fellows Committee is scientifically very heterogeneous by necessity simply because of the extremely wide range of scientific activities encompassed by the AGU. Since the Committee must read up to 100 or more dossiers, the following guidelines are provided to help nominators present the strongest package possible: The most eminent, outstanding, and deserving members of our community must first be identified and nominated.

  17. Immune defence under extreme ambient temperature.

    PubMed

    Seppälä, Otto; Jokela, Jukka

    2011-02-23

    Owing to global climate change, the extreme weather conditions are predicted to become more frequent, which is suggested to have an even greater impact on ecological interactions than the gradual increase in average temperatures. Here, we examined whether exposure to high ambient temperature affects immune function of the great pond snail (Lymnaea stagnalis). We quantified the levels of several immune traits from snails maintained in a non-stressful temperature (15°C) and in an extreme temperature (30°C) that occurs in small ponds during hot summers. We found that snails exposed to high temperature had weaker immune defence, which potentially predisposes them to infections. However, while phenoloxidase and antibacterial activity of snail haemolymph were reduced at high temperature, haemocyte concentration was not affected. This suggests that the effect of high temperature on snail susceptibility to infections may vary across different pathogens because different components of invertebrate immune defence have different roles in resistance.

  18. A quantitative analysis of extreme choice.

    PubMed

    Davison, M; Jones, B M

    1995-09-01

    Six homing pigeons were trained on a variety of concurrent variable-interval schedules in a switching-key procedure. Unlike previous work, reinforcer ratios of up to 160 to 1 and concurrent extinction variable-interval schedules were arranged in order to investigate choice when reinforcer-frequency outcomes were extremely different. The data obtained over 11 conditions were initially analyzed according to the generalized matching law, which fitted the data well. The generalized matching law was then fitted only to conditions in which the reinforcer ratios were between 1 to 10 and 10 to 1. The deviations of choice measures from the other four more extreme reinforcer-ratio conditions were significantly more towards equal choice than predicted by this second generalized matching fit. A contingency-discriminability model, which predicts such deviations, described the data more effectively than did the generalized matching law, and also correctly predicted the maintenance of responding on both alternatives when one was associated with extinction.

  19. Predictability of Extreme Events in Social Media

    PubMed Central

    Miotto, José M.; Altmann, Eduardo G.

    2014-01-01

    It is part of our daily social-media experience that seemingly ordinary items (videos, news, publications, etc.) unexpectedly gain an enormous amount of attention. Here we investigate how unexpected these extreme events are. We propose a method that, given some information on the items, quantifies the predictability of events, i.e., the potential of identifying in advance the most successful items. Applying this method to different data, ranging from views in YouTube videos to posts in Usenet discussion groups, we invariantly find that the predictability increases for the most extreme events. This indicates that, despite the inherently stochastic collective dynamics of users, efficient prediction is possible for the most successful items. PMID:25369138

  20. Predictability of extreme events in social media.

    PubMed

    Miotto, José M; Altmann, Eduardo G

    2014-01-01

    It is part of our daily social-media experience that seemingly ordinary items (videos, news, publications, etc.) unexpectedly gain an enormous amount of attention. Here we investigate how unexpected these extreme events are. We propose a method that, given some information on the items, quantifies the predictability of events, i.e., the potential of identifying in advance the most successful items. Applying this method to different data, ranging from views in YouTube videos to posts in Usenet discussion groups, we invariantly find that the predictability increases for the most extreme events. This indicates that, despite the inherently stochastic collective dynamics of users, efficient prediction is possible for the most successful items. PMID:25369138

  1. Extreme low frequency acoustic measurement system

    NASA Technical Reports Server (NTRS)

    Shams, Qamar A. (Inventor); Zuckerwar, Allan J. (Inventor)

    2013-01-01

    The present invention is an extremely low frequency (ELF) microphone and acoustic measurement system capable of infrasound detection in a portable and easily deployable form factor. In one embodiment of the invention, an extremely low frequency electret microphone comprises a membrane, a backplate, and a backchamber. The backchamber is sealed to allow substantially no air exchange between the backchamber and outside the microphone. Compliance of the membrane may be less than ambient air compliance. The backplate may define a plurality of holes and a slot may be defined between an outer diameter of the backplate and an inner wall of the microphone. The locations and sizes of the holes, the size of the slot, and the volume of the backchamber may be selected such that membrane motion is substantially critically damped.

  2. Disgust is a factor in extreme prejudice.

    PubMed

    Taylor, Kathleen

    2007-09-01

    Understanding intergroup prejudice is a dominant research focus for social psychology. Prejudice is usually conceptualized as a continuum of positive/negative affect, but this has limitations. It neither reflects people's ability to maintain simultaneous positive and negative stereotypes of others nor explains extreme prejudice (bigotry). Some researchers have proposed multidimensional models of prejudice in which different negative emotions are evoked depending on the situation. Extending this to bigotry raises the question of which emotions are most relevant. Therefore, this study looked at 'anti-group' texts--writings which promote extreme intergroup hostility--and analysed the frequency of emotive language. Findings suggest that bigotry may be distinguished by high levels of disgust.

  3. Improved Radiometry For Extreme-ultraviolet Lithography

    SciTech Connect

    Tarrio, C.; Vest, R.E.; Grantham, S.; Liu, K.; Lucatorto, T.B.; Shaw, P.S.

    2004-05-12

    The absolute cryogenic radiometer (ACR), an electrical-substitution-based detector, is the most accurate method for measurement of radiant power in the extreme ultraviolet. At the National Institute of Standards and Technology, ACR-based measurements are currently used as standards from the infrared and into the vacuum ultraviolet, however, no radiometric facilities are currently in operation with enough incident power to use an ACR in the extreme-ultraviolet region. Therefore, we have installed transfer optics on an existing beamline to allow the installation of the ACR as an additional endstation. We will describe the current radiometric beamline, the ACR, and the high-throughput beamline, and the transfer-optical system. Finally, we will present the performance of the transfer optics and measurements of the beam profile and incident power of the new endstation.

  4. Upper extremity quad splint: indications and technique.

    PubMed

    DeFroda, Steven F; Gil, Joseph A; Bokshan, Steven; Waryasz, Gregory

    2015-12-01

    Patients experiencing high-energy trauma evaluated at level I trauma centers often present with multiple injuries and varying levels of hemodynamic instability. The polytrauma patient requires immediate assessment and stabilization of their orthopedic injuries once the primary trauma survey is complete, and oftentimes, operative fixation of injuries is delayed while patients are resuscitated by general trauma services. The authors describe the application of the upper extremity "quad" splint which includes components of a sugar tong, intrinsic plus, thumb spica, and dorsal extension blocking splint and its indication for patients with multiple upper extremity fractures distal to the humerus. This splint is efficiently applied using minimal material while simultaneously allowing for the stabilizing aspects of 4 splints commonly applied in the emergency setting. PMID:26472510

  5. Gravitational radiation from extreme Kerr black hole

    NASA Technical Reports Server (NTRS)

    Sasaki, Misao; Nakamura, Takashi

    1989-01-01

    Gravitational radiation induced by a test particle falling into an extreme Kerr black hole was investigated analytically. Assuming the radiation is dominated by the infinite sequence of quasi-normal modes which has the limiting frequency m/(2M), where m is an azimuthal eigenvalue and M is the mass of the black hole, it was found that the radiated energy diverges logarithmically in time. Then the back reaction to the black hole was evaluated by appealing to the energy and angular momentum conservation laws. It was found that the radiation has a tendency to increase the ratio of the angular momentum to mass of the black hole, which is completely different from non-extreme case, while the contribution of the test particle is to decrease it.

  6. Extremely high energy neutrinos from cosmic strings

    SciTech Connect

    Berezinsky, Veniamin; Sabancilar, Eray; Vilenkin, Alexander

    2011-10-15

    Superstring theory and other supersymmetric theories predict the existence of relatively light, weakly interacting scalar particles, called moduli, with a universal form of coupling to matter. Such particles can be emitted from cusps of cosmic strings, where extremely large Lorentz factors are achieved momentarily. Highly boosted modulus bursts emanating from cusps subsequently decay into gluons; they generate parton cascades which in turn produce large numbers of pions and then neutrinos. Because of very large Lorentz factors, extremely high energy neutrinos, up to the Planck scale and above, are produced. For some model parameters, the predicted flux of neutrinos with energies > or approx. 10{sup 21} eV is observable by JEM-EUSO and by the future large radio detectors LOFAR and SKA.

  7. Bone Lengthening in the Pediatric Upper Extremity.

    PubMed

    Farr, Sebastian; Mindler, Gabriel; Ganger, Rudolf; Girsch, Werner

    2016-09-01

    ➤Bone lengthening has been used successfully for several congenital and acquired conditions in the pediatric clavicle, humerus, radius, ulna, and phalanges.➤Common indications for bone lengthening include achondroplasia, radial longitudinal deficiency, multiple hereditary exostosis, brachymetacarpia, symbrachydactyly, and posttraumatic and postinfectious growth arrest.➤Most authors prefer distraction rates of <1 mm/day for each bone in the upper extremity except the humerus, which can safely be lengthened by 1 mm/day.➤Most authors define success by the amount of radiographic bone lengthening, joint motion after lengthening, and subjective patient satisfaction rather than validated patient-related outcome measures.➤Bone lengthening of the upper extremity is associated with a high complication rate, with complications including pin-track infections, fixation device failure, nerve lesions, nonunion, fracture of regenerate bone, and joint dislocations. PMID:27605694

  8. Extreme events in total ozone over Arosa - Part 1: Application of extreme value theory

    NASA Astrophysics Data System (ADS)

    Rieder, H. E.; Staehelin, J.; Maeder, J. A.; Peter, T.; Ribatet, M.; Davison, A. C.; Stübi, R.; Weihs, P.; Holawe, F.

    2010-05-01

    In this study ideas from extreme value theory are for the first time applied in the field of stratospheric ozone research, because statistical analysis showed that previously used concepts assuming a Gaussian distribution (e.g. fixed deviations from mean values) of total ozone data do not adequately address the structure of the extremes. We show that statistical extreme value methods are appropriate to identify ozone extremes and to describe the tails of the Arosa (Switzerland) total ozone time series. In order to accommodate the seasonal cycle in total ozone, a daily moving threshold was determined and used, with tools from extreme value theory, to analyse the frequency of days with extreme low (termed ELOs) and high (termed EHOs) total ozone at Arosa. The analysis shows that the Generalized Pareto Distribution (GPD) provides an appropriate model for the frequency distribution of total ozone above or below a mathematically well-defined threshold, thus providing a statistical description of ELOs and EHOs. The results show an increase in ELOs and a decrease in EHOs during the last decades. The fitted model represents the tails of the total ozone data set with high accuracy over the entire range (including absolute monthly minima and maxima), and enables a precise computation of the frequency distribution of ozone mini-holes (using constant thresholds). Analyzing the tails instead of a small fraction of days below constant thresholds provides deeper insight into the time series properties. Fingerprints of dynamical (e.g. ENSO, NAO) and chemical features (e.g. strong polar vortex ozone loss), and major volcanic eruptions, can be identified in the observed frequency of extreme events throughout the time series. Overall the new approach to analysis of extremes provides more information on time series properties and variability than previous approaches that use only monthly averages and/or mini-holes and mini-highs.

  9. Extreme events in total ozone over Arosa - Part 1: Application of extreme value theory

    NASA Astrophysics Data System (ADS)

    Rieder, H. E.; Staehelin, J.; Maeder, J. A.; Peter, T.; Ribatet, M.; Davison, A. C.; Stübi, R.; Weihs, P.; Holawe, F.

    2010-10-01

    In this study ideas from extreme value theory are for the first time applied in the field of stratospheric ozone research, because statistical analysis showed that previously used concepts assuming a Gaussian distribution (e.g. fixed deviations from mean values) of total ozone data do not adequately address the structure of the extremes. We show that statistical extreme value methods are appropriate to identify ozone extremes and to describe the tails of the Arosa (Switzerland) total ozone time series. In order to accommodate the seasonal cycle in total ozone, a daily moving threshold was determined and used, with tools from extreme value theory, to analyse the frequency of days with extreme low (termed ELOs) and high (termed EHOs) total ozone at Arosa. The analysis shows that the Generalized Pareto Distribution (GPD) provides an appropriate model for the frequency distribution of total ozone above or below a mathematically well-defined threshold, thus providing a statistical description of ELOs and EHOs. The results show an increase in ELOs and a decrease in EHOs during the last decades. The fitted model represents the tails of the total ozone data set with high accuracy over the entire range (including absolute monthly minima and maxima), and enables a precise computation of the frequency distribution of ozone mini-holes (using constant thresholds). Analyzing the tails instead of a small fraction of days below constant thresholds provides deeper insight into the time series properties. Fingerprints of dynamical (e.g. ENSO, NAO) and chemical features (e.g. strong polar vortex ozone loss), and major volcanic eruptions, can be identified in the observed frequency of extreme events throughout the time series. Overall the new approach to analysis of extremes provides more information on time series properties and variability than previous approaches that use only monthly averages and/or mini-holes and mini-highs.

  10. Extreme Modulation Properties of Aromatic Fluorine

    SciTech Connect

    Burnett, Michael N; Gakh, Andrei A

    2011-01-01

    Thorough examination of the current literature as well as publicly available databases allowed us to qualify aromatic fluorine as a unique modulator of biological properties of organic compounds. In some rare cases, introduction of fluorine increased biological activity 100,000 times and even higher. We have also identified several examples where aromatic fluorine substantially reduced biological activity. Selected individual cases of extreme modulation are presented and discussed in the paper.

  11. Structural Extremes in a Cretaceous Dinosaur

    PubMed Central

    Sereno, Paul C.; Wilson, Jeffrey A.; Witmer, Lawrence M.; Whitlock, John A.; Maga, Abdoulaye; Ide, Oumarou; Rowe, Timothy A.

    2007-01-01

    Fossils of the Early Cretaceous dinosaur, Nigersaurus taqueti, document for the first time the cranial anatomy of a rebbachisaurid sauropod. Its extreme adaptations for herbivory at ground-level challenge current hypotheses regarding feeding function and feeding strategy among diplodocoids, the larger clade of sauropods that includes Nigersaurus. We used high resolution computed tomography, stereolithography, and standard molding and casting techniques to reassemble the extremely fragile skull. Computed tomography also allowed us to render the first endocast for a sauropod preserving portions of the olfactory bulbs, cerebrum and inner ear, the latter permitting us to establish habitual head posture. To elucidate evidence of tooth wear and tooth replacement rate, we used photographic-casting techniques and crown thin sections, respectively. To reconstruct its 9-meter postcranial skeleton, we combined and size-adjusted multiple partial skeletons. Finally, we used maximum parsimony algorithms on character data to obtain the best estimate of phylogenetic relationships among diplodocoid sauropods. Nigersaurus taqueti shows extreme adaptations for a dinosaurian herbivore including a skull of extremely light construction, tooth batteries located at the distal end of the jaws, tooth replacement as fast as one per month, an expanded muzzle that faces directly toward the ground, and hollow presacral vertebral centra with more air sac space than bone by volume. A cranial endocast provides the first reasonably complete view of a sauropod brain including its small olfactory bulbs and cerebrum. Skeletal and dental evidence suggests that Nigersaurus was a ground-level herbivore that gathered and sliced relatively soft vegetation, the culmination of a low-browsing feeding strategy first established among diplodocoids during the Jurassic. PMID:18030355

  12. Structural extremes in a cretaceous dinosaur.

    PubMed

    Sereno, Paul C; Wilson, Jeffrey A; Witmer, Lawrence M; Whitlock, John A; Maga, Abdoulaye; Ide, Oumarou; Rowe, Timothy A

    2007-11-21

    Fossils of the Early Cretaceous dinosaur, Nigersaurus taqueti, document for the first time the cranial anatomy of a rebbachisaurid sauropod. Its extreme adaptations for herbivory at ground-level challenge current hypotheses regarding feeding function and feeding strategy among diplodocoids, the larger clade of sauropods that includes Nigersaurus. We used high resolution computed tomography, stereolithography, and standard molding and casting techniques to reassemble the extremely fragile skull. Computed tomography also allowed us to render the first endocast for a sauropod preserving portions of the olfactory bulbs, cerebrum and inner ear, the latter permitting us to establish habitual head posture. To elucidate evidence of tooth wear and tooth replacement rate, we used photographic-casting techniques and crown thin sections, respectively. To reconstruct its 9-meter postcranial skeleton, we combined and size-adjusted multiple partial skeletons. Finally, we used maximum parsimony algorithms on character data to obtain the best estimate of phylogenetic relationships among diplodocoid sauropods. Nigersaurus taqueti shows extreme adaptations for a dinosaurian herbivore including a skull of extremely light construction, tooth batteries located at the distal end of the jaws, tooth replacement as fast as one per month, an expanded muzzle that faces directly toward the ground, and hollow presacral vertebral centra with more air sac space than bone by volume. A cranial endocast provides the first reasonably complete view of a sauropod brain including its small olfactory bulbs and cerebrum. Skeletal and dental evidence suggests that Nigersaurus was a ground-level herbivore that gathered and sliced relatively soft vegetation, the culmination of a low-browsing feeding strategy first established among diplodocoids during the Jurassic.

  13. Extreme commutative quantum observables are sharp

    NASA Astrophysics Data System (ADS)

    Heinosaari, Teiko; Pellonpää, Juha-Pekka

    2011-08-01

    It is well known that, in the description of quantum observables, positive operator valued measures (POVMs) generalize projection valued measures (PVMs) and they also turn out be more optimal in many tasks. We show that a commutative POVM is an extreme point in the convex set of all POVMs if and only if it is a PVM. This results implies that non-commutativity is a necessary ingredient to overcome the limitations of PVMs.

  14. Extreme Ultraviolet Explorer Science Operation Center

    NASA Technical Reports Server (NTRS)

    Wong, G. S.; Kronberg, F. A.; Meriwether, H. D.; Wong, L. S.; Grassi, C. L.

    1993-01-01

    The EUVE Science Operations Center (ESOC) is a satellite payload operations center for the Extreme Ultraviolet Explorer project, located on the Berkeley campus of the University of California. The ESOC has the primary responsibility for commanding the EUVE telescopes and monitoring their telemetry. The ESOC is one of a very few university-based satellite operations facilities operating with NASA. This article describes the history, operation, and advantages of the ESOC as an on-campus operations center.

  15. Endurance cycling results in extreme environments

    NASA Technical Reports Server (NTRS)

    Guertin, S. M.; Nguyen, D. N.; Scheick, L. Z.

    2003-01-01

    A new test bed for life testing flash memories in extreme environments is introducted. the test bed is based on a state-of-the-art development board. Since space applications often desire state-of-the-art devices, such a basis seems appropriate. Comparison of this tester to other such systems, including those with data presented here in the past is made. Limitations of different testers for varying applications are discussed. Recently developed data, using this test bed is also presented.

  16. Horseshoe Appendix: An Extremely Rare Appendiceal Anomaly.

    PubMed

    Singh, Ch Gyan; Nyuwi, Kuotho T; Rangaswamy, Raju; Ezung, Yibenthung S; Singh, H Manihar

    2016-03-01

    Appendiceal anomalies are extremely rare malformations that are usually found incidentally. Agenesis and duplication of the appendix has been well documented however, the cases of horseshoe appendix reported is very limited, only four cases reported so far. Here, we report a four and half-year-old who underwent interval appendectomy. Intraoperatively both the ends of the appendix were found to be communicating with the cecum with two separate base or stump located at a sagital disposal- the so called "horseshoe appendix".

  17. Extreme Earthquake Risk Estimation by Hybrid Modeling

    NASA Astrophysics Data System (ADS)

    Chavez, M.; Cabrera, E.; Ashworth, M.; Garcia, S.; Emerson, D.; Perea, N.; Salazar, A.; Moulinec, C.

    2012-12-01

    The estimation of the hazard and the economical consequences i.e. the risk associated to the occurrence of extreme magnitude earthquakes in the neighborhood of urban or lifeline infrastructure, such as the 11 March 2011 Mw 9, Tohoku, Japan, represents a complex challenge as it involves the propagation of seismic waves in large volumes of the earth crust, from unusually large seismic source ruptures up to the infrastructure location. The large number of casualties and huge economic losses observed for those earthquakes, some of which have a frequency of occurrence of hundreds or thousands of years, calls for the development of new paradigms and methodologies in order to generate better estimates, both of the seismic hazard, as well as of its consequences, and if possible, to estimate the probability distributions of their ground intensities and of their economical impacts (direct and indirect losses), this in order to implement technological and economical policies to mitigate and reduce, as much as possible, the mentioned consequences. Herewith, we propose a hybrid modeling which uses 3D seismic wave propagation (3DWP) and neural network (NN) modeling in order to estimate the seismic risk of extreme earthquakes. The 3DWP modeling is achieved by using a 3D finite difference code run in the ~100 thousands cores Blue Gene Q supercomputer of the STFC Daresbury Laboratory of UK, combined with empirical Green function (EGF) techniques and NN algorithms. In particular the 3DWP is used to generate broadband samples of the 3D wave propagation of extreme earthquakes (plausible) scenarios corresponding to synthetic seismic sources and to enlarge those samples by using feed-forward NN. We present the results of the validation of the proposed hybrid modeling for Mw 8 subduction events, and show examples of its application for the estimation of the hazard and the economical consequences, for extreme Mw 8.5 subduction earthquake scenarios with seismic sources in the Mexican

  18. Throwing injuries of the upper extremity.

    PubMed

    Patel, Neel B; Thomas, Stephen; Lazarus, Martin L

    2013-03-01

    The overhead throwing motion is a complex sequence of maneuvers that requires coordinated muscle activity in the upper and lower extremities. The shoulder and elbow are subject to multidirectional forces and are particularly vulnerable to injury during specific phases of the overhead throwing motion. Ligamentous, tendinous, neural, and osseous pathology that may occur in the shoulder or elbow of an overhead-throwing athlete will be discussed, with an emphasis on the role of MR imaging and MR arthrography.

  19. Glenn Extreme Environments Rig (GEER) Independent Review

    NASA Technical Reports Server (NTRS)

    Jankovsky, Robert S.; Smiles, Michael D.; George, Mark A.; Ton, Mimi C.; Le, Son K.

    2015-01-01

    The Chief of the Space Science Project Office at Glenn Research Center (GRC) requested support from the NASA Engineering and Safety Center (NESC) to satisfy a request from the Science Mission Directorate (SMD) Associate Administrator and the Planetary Science Division Chief to obtain an independent review of the Glenn Extreme Environments Rig (GEER) and the operational controls in place for mitigating any hazard associated with its operation. This document contains the outcome of the NESC assessment.

  20. Adaptive prosthetics for the lower extremity.

    PubMed

    Carroll, K

    2001-06-01

    The potential for lifestyle recovery is tremendous for most lower extremity amputees. The amazing and ever-expanding array of adaptive prosthetics can help make the devastating loss of amputation more bearable for patients, their families, and their health care team. The new amputee, in a state of shock and grief, does not know what his or her prosthetic options are. It is crucial that the surgeon is knowledgeable about what the patient can have and what the patient needs to ask for. Dana Bowman stated: Ideally, the new amputee should say to their doctor, "I'd like my leg to be lightweight, flexible, durable, comfortable. I want to do sports or I want to ride bikes with my kids." Whatever it is they like to do. I was told I would never be able to wear two dynamic feet and that my sky diving days were over. I said, "Well how do you know? Can't I try?" It took years to find out what I could have and then to find people to help me get it. The prosthetic prescription the physician writes is the patient's gateway to the kind of prosthetics that will enable him or her to pursue the activities of their life. Often, new amputees end up with the bare minimum prosthesis, which can cause problems with comfort and mobility. A poorly designed or badly fitting prosthesis is as disabling as the actual amputation. When the surgeon can help the amputee and his or her family understand what kind of prosthetic choices are available, it establishes an optimistic outlook that is highly beneficial to the entire recovery process physically and mentally. "When I lost my leg, if someone would have told me that I could at least try to run again, that would have meant a lot," said Brian Frasure. "Getting that positive mental attitude is every bit as important as having good medical and prosthetic care." By asking probing questions about the patient's preamputation lifestyle and postamputation goals, the physician can write a prescription for truly adaptive prosthetics. The surgeon should

  1. Metagenomic taxonomic classification using extreme learning machines.

    PubMed

    Rasheed, Zeehasham; Rangwala, Huzefa

    2012-10-01

    Next-generation sequencing technologies have allowed researchers to determine the collective genomes of microbial communities co-existing within diverse ecological environments. Varying species abundance, length and complexities within different communities, coupled with discovery of new species makes the problem of taxonomic assignment to short DNA sequence reads extremely challenging. We have developed a new sequence composition-based taxonomic classifier using extreme learning machines referred to as TAC-ELM for metagenomic analysis. TAC-ELM uses the framework of extreme learning machines to quickly and accurately learn the weights for a neural network model. The input features consist of GC content and oligonucleotides. TAC-ELM is evaluated on two metagenomic benchmarks with sequence read lengths reflecting the traditional and current sequencing technologies. Our empirical results indicate the strength of the developed approach, which outperforms state-of-the-art taxonomic classifiers in terms of accuracy and implementation complexity. We also perform experiments that evaluate the pervasive case within metagenome analysis, where a species may not have been previously sequenced or discovered and will not exist in the reference genome databases. TAC-ELM was also combined with BLAST to show improved classification results. Code and Supplementary Results: http://www.cs.gmu.edu/~mlbio/TAC-ELM (BSD License). PMID:22849369

  2. Extreme human breath-hold diving.

    PubMed

    Ferretti, G

    2001-04-01

    In this paper, the respiratory, circulatory and metabolic adjustments to human extreme breath-hold diving are reviewed. A survey of the literature reveals that in extreme divers, adaptive mechanisms take place that allow prolongation of apnoea beyond the limits attained by non-diving subjects, and preservation of oxygen stores during the dives. The occurrence of a diving response, including peripheral vasoconstriction, increased arterial blood pressure, bradycardia and lowered cardiac output, is strongly implicated. Some peripheral regions may be excluded from perfusion, with consequent reliance on anaerobic metabolism. In addition, extreme breath-hold divers show a blunted ventilatory response to carbon dioxide breathing, possibly as a consequence of frequent exposure to high carbon dioxide partial pressures during the dives. These mechanisms allow the attainment of particularly low alveolar oxygen (< 30 mmHg) and high alveolar carbon dioxide (> 50 mmHg) partial pressures at the end of maximal dry breath-holds, and reduce oxygen consumption during the dive at the expense of increased anaerobic glycolysis (rate of blood lactate accumulation > 0.04 mM.s-1). The current absolute world record for depth in breath-hold diving is 150 m. Its further improvement depends upon how far the equilibrium between starting oxygen stores, the overall rate of energy expenditure, the fraction of energy provided by anaerobic metabolism and the diving speed can be pushed, with consciousness upon emersion. The ultimate limit to breath-hold diving records may indeed be imposed by an energetic constraint. PMID:11374109

  3. Beating the odds--surviving extreme hyperkalemia.

    PubMed

    Muck, Philip M; Letterer, Sebastian; Lindner, Ulrich; Lehnert, Hendrik; Haas, Christian Stefan

    2012-01-01

    Severe hyperkalemia (>7 mmol/L) is a medical emergency because of possible fatal arrhythmias. We here report the case of a 58-year-old woman surviving extreme hyperkalemia (>10 mmol/L). The patient with a history of congestive heart failure, a DDD pacemaker and mild chronic renal insufficiency was admitted with progressive weakness and sudden onset of hypotension and bradycardia in the absence of any pacemaker action. Laboratory tests revealed an extreme serum potassium level of 10.1 mmol/L, with a slightly elevated serum creatinine of 149 μmol/L. Treatment with norepinephrine, sodium bicarbonate, and insulin improved both the hemodynamic situation and the serum potassium with subsequent regaining pacemaker actions even before additional hemodialysis normalized the potassium level. A thorough investigation demonstrated that several mechanisms contributed to the extreme potassium level: urinalysis and a low transtubular potassium gradient in the presence of metabolic acidosis with normal anion gap pointed to preexisting interstitial nephritis, with renal tubular acidosis type IV as the predisposing factor, whereas several drugs and acute impairment of renal function contributed to the dangerous situation. Despite the odds for fatal outcome, the patient recovered completely, and long-term management was initiated to prevent recurrent hyperkalemia.

  4. On the Bimodality of ENSO Cycle Extremes

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    1999-01-01

    On the basis of sea surface temperature in the Nino 3.4 region (5 deg N-5 deg S, 120 deg- 170 deg W) during the interval of 1950-1997, Kevin Trenberth previously has identified some 16 El Nino and 10 La Nina, these 26 events representing the extremes of the quasi-periodic El Nino-Southern Oscillation (ENSO) cycle. Runs testing shows that the duration and recurrence period associated with these extremes vary randomly, as does the sequencing of the extremes. Hence, the frequency of occurrence of these events during the 1990s, especially, for El Nino should not be construed as being significantly different from that of previous epochs. Additionally, the distribution of duration for both El Nino and La Nina looks bimodal, consisting of two preferred modes - about 8 and 16 months in length for El Nino and about 9 and 18 months in length for La Nina. Likewise, the distribution of recurrence period, especially, for El Nino looks bimodal, consisting of two preferred modes - about 21 and 50 months in length. Scatter plots of the recurrence period versus duration for El Nino strongly suggest preferential associations between them, linking shorter (longer) duration with shorter (longer) recurrence period. Because the last known onset of El Nino occurred in April 1997 and the event was of longer than average duration, one infers that the onset of the next expected El Nino will not occur until February 2000 or later.

  5. Developing Effective Communications about Extreme Weather Risks.

    NASA Astrophysics Data System (ADS)

    Bruine de Bruin, W.

    2014-12-01

    Members of the general public often face complex decisions about the risks that they face, including those associated with extreme weather and climate change adaptation. Scientific experts may be asked to develop communications with the goal of improving people's understanding of weather and climate risks, and informing people's decisions about how to protect against these risks. Unfortunately, scientific experts' communication efforts may fail if they lack information about what people need or want to know to make more informed decisions or what wording people prefer use to describe relevant concepts. This presentation provides general principles for developing effective risk communication materials that aim for widespread dissemination, such as brochures and websites. After a brief review of the social science evidence on how to design effective risk communication materials, examples will focus on communications about extreme weather events and climate change. Specifically, data will be presented from ongoing projects on flood risk perception, public preparedness for heat waves, and public perceptions of climate change. The presentation will end with specific recommendations about how to improve recipients' understanding about risks and inform decisions. These recommendations should be useful to scientific experts who aim to communicate about extreme weather, climate change, or other risks.

  6. Chiral gravity, log gravity, and extremal CFT

    SciTech Connect

    Maloney, Alexander; Song Wei; Strominger, Andrew

    2010-03-15

    We show that the linearization of all exact solutions of classical chiral gravity around the AdS{sub 3} vacuum have positive energy. Nonchiral and negative-energy solutions of the linearized equations are infrared divergent at second order, and so are removed from the spectrum. In other words, chirality is confined and the equations of motion have linearization instabilities. We prove that the only stationary, axially symmetric solutions of chiral gravity are BTZ black holes, which have positive energy. It is further shown that classical log gravity--the theory with logarithmically relaxed boundary conditions--has finite asymptotic symmetry generators but is not chiral and hence may be dual at the quantum level to a logarithmic conformal field theories (CFT). Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We formally evaluate the Euclidean sum over geometries of chiral gravity and show that it gives precisely the holomorphic extremal CFT partition function. The modular invariance and integrality of the expansion coefficients of this partition function are consistent with the existence of an exact quantum theory of chiral gravity. We argue that the problem of quantizing chiral gravity is the holographic dual of the problem of constructing an extremal CFT, while quantizing log gravity is dual to the problem of constructing a logarithmic extremal CFT.

  7. Relating Regional Arctic Sea Ice and climate extremes over Europe

    NASA Astrophysics Data System (ADS)

    Ionita-Scholz, Monica; Grosfeld, Klaus; Lohmann, Gerrit; Scholz, Patrick

    2016-04-01

    The potential increase of temperature extremes under climate change is a major threat to society, as temperature extremes have a deep impact on environment, hydrology, agriculture, society and economy. Hence, the analysis of the mechanisms underlying their occurrence, including their relationships with the large-scale atmospheric circulation and sea ice concentration, is of major importance. At the same time, the decline in Arctic sea ice cover during the last 30 years has been widely documented and it is clear that this change is having profound impacts at regional as well as planetary scale. As such, this study aims to investigate the relation between the autumn regional sea ice concentration variability and cold winters in Europe, as identified by the numbers of cold nights (TN10p), cold days (TX10p), ice days (ID) and consecutive frost days (CFD). We analyze the relationship between Arctic sea ice variation in autumn (September-October-November) averaged over eight different Arctic regions (Barents/Kara Seas, Beaufort Sea, Chukchi/Bering Seas, Central Arctic, Greenland Sea, Labrador Sea/Baffin Bay, Laptev/East Siberian Seas and Northern Hemisphere) and variations in atmospheric circulation and climate extreme indices in the following winter season over Europe using composite map analysis. Based on the composite map analysis it is shown that the response of the winter extreme temperatures over Europe is highly correlated/connected to changes in Arctic sea ice variability. However, this signal is not symmetrical for the case of high and low sea ice years. Moreover, the response of temperatures extreme over Europe to sea ice variability over the different Arctic regions differs substantially. The regions which have the strongest impact on the extreme winter temperature over Europe are: Barents/Kara Seas, Beaufort Sea, Central Arctic and the Northern Hemisphere. For the years of high sea ice concentration in the Barents/Kara Seas there is a reduction in the number

  8. Measures of Economic Impacts of Weather Extremes.

    NASA Astrophysics Data System (ADS)

    Changnon, Stanley D.

    2003-09-01

    One of the primary driving forces behind weather research and development has been the losses caused by weather extremes. Unfortunately, available loss values have been more qualitative than quantitative. There has never been a concerted, organized effort to collect and quality control economic impact data for weather extremes. Numerous studies have been made, resulting in widely varying estimates of losses, and these have been limited by 1) an inability to access certain types of loss data; 2) a lack of attention to indirect, delayed impacts, including benefits; and 3) diverse and inconsistent sources of loss data. Numerous problems have resulted from the poor estimates of loss and lack of understanding of the data uncertainties. Federal relief payments for major events have escalated partly as a result of insufficient-data to detect and understand society's changing vulnerability to extremes. Controversies over relief payments for major damaging events have occurred as a result of imprecise loss estimates. The insurance industry suffered major storm-related losses in the 1990s because it lacked a database on weather-produced losses and was unable to anticipate time-shifting risks in setting rates. The absence of quality impact data has also led to questionable research priorities, and has generated incorrect perceptions in the public and media about the magnitude of impacts of events. The lack of precise loss values also limits adequate planning for future impacts, which is apt to lead to increased losses as society's vulnerability to extremes continues to increase. Recent pressures, including several major weather losses since 1988, and concern over the impacts of more extremes due to global warming, have led to better estimates of impacts. These pressures and government and insurance industry recognition of the need to better understand the ever-increasing costs have led to recent national assessments, calling for better impact data. The nation needs a

  9. Upper-extremity deep venous thrombosis: a review.

    PubMed

    Mai, Cuc; Hunt, Daniel

    2011-05-01

    Upper-extremity deep venous thrombosis is less common than lower-extremity deep venous thrombosis. However, upper-extremity deep venous thrombosis is associated with similar adverse consequences and is becoming more common in patients with complex medical conditions requiring central venous catheters or wires. Although guidelines suggest that this disorder be managed using approaches similar to those for lower-extremity deep venous thrombosis, studies are refining the prognosis and management of upper-extremity deep venous thrombosis. Physicians should be familiar with the diagnostic and treatment considerations for this disease. This review will differentiate between primary and secondary upper-extremity deep venous thromboses; assess the risk factors and clinical sequelae associated with upper-extremity deep venous thrombosis, comparing these with lower-extremity deep venous thrombosis; and describe an approach to treatment and prevention of secondary upper-extremity deep venous thrombosis based on clinical evidence.

  10. Measuring Dependence on Imported Oil

    EIA Publications

    1995-01-01

    U.S. dependence on imported oil can be measured in at least two ways. The differences hinge largely on whether oil imports are defined as net imports (total imports minus exports) or as total imports. EIA introduces a revised table that expresses dependence on imports in terms of both measures.

  11. Probabilistic models for assessment of extreme temperatures and relative humidity in Lithuania

    NASA Astrophysics Data System (ADS)

    Alzbutas, Robertas; Šeputytė, Ilona

    2015-04-01

    Extreme temperatures are fairly common natural phenomenon in Lithuania. They have mainly negative effects both on the environment and humans. Thus there are important to perform probabilistic and statistical analyzes of possibly extreme temperature values and their time-dependant changes. This is especially important in areas where technical objects (sensitive to the extreme temperatures) are foreseen to be constructed. In order to estimate the frequencies and consequences of possible extreme temperatures, the probabilistic analysis of the event occurrence and its uncertainty has been performed: statistical data have been collected and analyzed. The probabilistic analysis of extreme temperatures in Lithuanian territory is based on historical data taken from Lithuanian Hydrometeorology Service, Dūkštas Meteorological Station, Lithuanian Energy Institute and Ignalina NNP Environmental Protection Department of Environmental Monitoring Service. The main objective of performed work was the probabilistic assessment of occurrence and impact of extreme temperature and relative humidity occurring in whole Lithuania and specifically in Dūkštas region where Ignalina Nuclear Power Plant is closed for decommissioning. In addition, the other purpose of this work was to analyze the changes of extreme temperatures. The probabilistic analysis of extreme temperatures increase in Lithuanian territory was based on more than 50 years historical data. The probabilistic assessment was focused on the application and comparison of Gumbel, Weibull and Generalized Value (GEV) distributions, enabling to select a distribution, which has the best fit for data of extreme temperatures. In order to assess the likelihood of extreme temperatures different probabilistic models were applied to evaluate the probability of exeedance of different extreme temperatures. According to the statistics and the relationship between return period and probabilities of temperatures the return period for 30

  12. US CLIVAR Extremes Working Group Results, Recommendations, and Recourses

    NASA Astrophysics Data System (ADS)

    Grotjahn, R.

    2015-12-01

    The topic of extreme weather and climate is very broad. One can easily list a dozen different types of atmospheric extreme phenomena. In addition, some extreme phenomena have multiple types of extremes as well as categories of extremes. The first US CLIVAR working group on extremes (EWG) chose to narrow the extreme phenomena to temperature and precipitation extremes having a time scale of a few days to a week. The primary extremes considered were short term heat waves, cold air outbreaks, and extreme precipitation not from tropical cyclones. All of these have produced multi-billion dollar losses in recent years. Even this subset of extremes is very broad, so additional focus was placed upon the large scale meteorological patterns (LSMPs) that accompany these extremes. This working group was most active from its inception in 2012 until its nominal ending in 2015. Additional work continues, including follow-on activities spawned or informed by the EWG. In this talk, the EWG activities are summarized in four areas: data for extremes, statistical analyses applicable to extremes, synoptic-dynamics of these extremes, and simulation of these extremes in climate models. The emphasis will be upon knowledge gaps and recommended further actions in these four areas. The recommendations span basic science through applications. The EWG participation included input into the US CLIVAR science plan, as one of the four research challenges there being 'extremes'. A scientific session at this AGU meeting was a direct outgrowth of the EWG 2013 workshop. Other follow-on work includes consultation with various national and international efforts in extremes. Finally, some possible future applications of the EWG efforts, such as adequate datasets and climate model diagnostic tools, will be mentioned that may inform providers of information having direct interest to end-users.

  13. Exposure of US Adolescents to Extremely Violent Movies

    PubMed Central

    Worth, Keilah A.; Chambers, Jennifer Gibson; Nassau, Daniel H.; Rakhra, Balvinder K.; Sargent, James D.

    2009-01-01

    Objective Despite concerns about exposure to violent media, there are few data on youth exposure to violent movies. In this study we examined such exposure among young US adolescents. Methods We used a random-digit-dial survey of 6522 US adolescents aged 10 to 14 years fielded in 2003. Using previously validated methods, we determined the percentage and number of US adolescents who had seen each of 534 recently released movies. We report results for the 40 that were rated R for violence by the Motion Picture Association of America, UK 18 by the British Board of Film Classification and coded for extreme violence by trained content coders. Results The 40 violent movies were seen by a median of 12.5% of an estimated 22 million US adolescents aged 10 to 14 years. The most popular violent movie, Scary Movie, was seen by >10 million (48.1%) children, 1 million of whom were 10 years of age. Watching extremely violent movies was associated with being male, older, nonwhite, having less-educated parents, and doing poorly in school. Black male adolescents were at particularly high risk for seeing these movies; for example Blade, Training Day, and Scary Movie were seen, respectively, by 37.4%, 27.3%, and 48.1% of the sample overall versus 82.0%, 81.0%, and 80.8% of black male adolescents. Violent movie exposure was also associated with measures of media parenting, with high-exposure adolescents being significantly more likely to have a television in their bedroom and to report that their parents allowed them to watch R-rated movies. Conclusions This study documents widespread exposure of young US adolescents to movies with extreme graphic violence from movies rated R for violence and raises important questions about the effectiveness of the current movie-rating system. PMID:18676548

  14. Extreme Cranial Ontogeny in the Upper Cretaceous Dinosaur Pachycephalosaurus

    PubMed Central

    Horner, John R.; Goodwin, Mark B.

    2009-01-01

    Background Extended neoteny and late stage allometric growth increase morphological disparity between growth stages in at least some dinosaurs. Coupled with relatively low dinosaur density in the Upper Cretaceous of North America, ontogenetic transformational representatives are often difficult to distinguish. For example, many hadrosaurids previously reported to represent relatively small lambeosaurine species were demonstrated to be juveniles of the larger taxa. Marginocephalians (pachycephalosaurids + ceratopsids) undergo comparable and extreme cranial morphological change during ontogeny. Methodology/Principal Findings Cranial histology, morphology and computer tomography reveal patterns of internal skull development that show the purported diagnostic characters for the pachycephalosaurids Dracorex hogwartsia and Stygimoloch spinifer are ontogenetically derived features. Coronal histological sections of the frontoparietal dome of an adult Pachycephalosaurus wyomingensis reveal a dense structure composed of metaplastic bone with a variety of extremely fibrous and acellular tissue. Coronal histological sections and computer tomography of a skull and frontoparietal dome of Stygimoloch spinifer reveal an open intrafrontal suture indicative of a subadult stage of development. These dinosaurs employed metaplasia to rapidly grow and change the size and shape of their horns, cranial ornaments and frontoparietal domes, resulting in extreme cranial alterations during late stages of growth. We propose that Dracorex hogwartsia, Stygimoloch spinifer and Pachycephalosaurus wyomingensis are the same taxon and represent an ontogenetic series united by shared morphology and increasing skull length. Conclusions/Significance Dracorex hogwartsia (juvenile) and Stygimoloch spinifer (subadult) are reinterpreted as younger growth stages of Pachycephalosaurus wyomingensis (adult). This synonymy reduces the number of pachycephalosaurid taxa from the Upper Cretaceous of North America

  15. Assessing mid-latitude dynamics in extreme event attribution systems

    NASA Astrophysics Data System (ADS)

    Mitchell, Daniel; Davini, Paolo; Harvey, Ben; Massey, Neil; Haustein, Karsten; Woollings, Tim; Jones, Richard; Otto, Fredi; Guillod, Benoit; Sparrow, Sarah; Wallom, David; Allen, Myles

    2016-08-01

    Atmospheric modes of variability relevant for extreme temperature and precipitation events are evaluated in models currently being used for extreme event attribution. A 100 member initial condition ensemble of the global circulation model HadAM3P is compared with both the multi-model ensemble from the Coupled Model Inter-comparison Project, Phase 5 (CMIP5) and the CMIP5 atmosphere-only counterparts (AMIP5). The use of HadAM3P allows for huge ensembles to be computed relatively fast, thereby providing unique insights into the dynamics of extremes. The analysis focuses on mid Northern Latitudes (primarily Europe) during winter, and is compared with ERA-Interim reanalysis. The tri-modal Atlantic eddy-driven jet distribution is remarkably well captured in HadAM3P, but not so in the CMIP5 or AMIP5 multi-model mean, although individual models fare better. The well known underestimation of blocking in the Atlantic region is apparent in CMIP5 and AMIP5, and also, to a lesser extent, in HadAM3P. Pacific blocking features are well produced in all modeling initiatives. Blocking duration is biased towards models reproducing too many short-lived events in all three modelling systems. Associated storm tracks are too zonal over the Atlantic in the CMIP5 and AMIP5 ensembles, but better simulated in HadAM3P with the exception of being too weak over Western Europe. In all cases, the CMIP5 and AMIP5 performances were almost identical, suggesting that the biases in atmospheric modes considered here are not strongly coupled to SSTs, and perhaps other model characteristics such as resolution are more important. For event attribution studies, it is recommended that rather than taking statistics over the entire CMIP5 or AMIP5 available models, only models capable of producing the relevant dynamical phenomena be employed.

  16. Extremely varied phenotypes in granular corneal dystrophy type 2 heterozygotes

    PubMed Central

    Han, Kyung Eun; Choi, Seung-il; Chung, Woo Suk; Jung, Se Hwan; Katsanis, Nicholas; Kim, Tae-im

    2012-01-01

    Purpose To investigate the phenotypic variability of patients bearing the heterozygous R124H mutation in the TGFBI (transforming growth factor-beta-induced) gene that causes granular corneal dystrophy type 2 (GCD2). Methods We describe the phenotypic range of GCD2 heterozygotes for the common R124H mutation in TGFBI; seven with an extremely mild phenotype and six with an extremely severe phenotype. Detailed slit-lamp photographs of these patients were generated. All patients had no history of ocular surgery and were diagnosed as being heterozygous for GCD2 by DNA analysis from peripheral blood. Expression levels of transforming growth factor-beta-induced protein (TGFBIp) were compared among cultured corneal fibroblasts from ten normal donors. Results We report profound differences in the severity of the phenotype across our case series. Two patients with a mild phenotype were diagnosed as unaffected at presentation; however follow-up examinations revealed granular deposits. Importantly, we also observed familial clustering of phenotypic variance; five patients from two families with a mild phenotype showed a similarly mild phenotype within family members. Similarly, six patients from two families with severe phenotypes showed corneal deposits with similar patterns and severity within each distinct family, but distinct patterns between families. TGFBIp expressions from different donor derived cultured corneal fibroblasts were different between one another. Conclusions GCD2 heterozygotes have extremely varied phenotypes between individual patients. However phenotypes were broadly consistent within families, suggesting that the observed variable expressivity might be regulated by other genetic factors that could influence the abundance of TGFBIp or the function of the pathway. From a clinical perspective, our data also highlighted that genetic analysis and meticulous slit-lamp examination in both eyes at multiple time intervals is necessary. PMID:22815629

  17. Robot-aided assessment of lower extremity functions: a review.

    PubMed

    Maggioni, Serena; Melendez-Calderon, Alejandro; van Asseldonk, Edwin; Klamroth-Marganska, Verena; Lünenburger, Lars; Riener, Robert; van der Kooij, Herman

    2016-01-01

    The assessment of sensorimotor functions is extremely important to understand the health status of a patient and its change over time. Assessments are necessary to plan and adjust the therapy in order to maximize the chances of individual recovery. Nowadays, however, assessments are seldom used in clinical practice due to administrative constraints or to inadequate validity, reliability and responsiveness. In clinical trials, more sensitive and reliable measurement scales could unmask changes in physiological variables that would not be visible with existing clinical scores.In the last decades robotic devices have become available for neurorehabilitation training in clinical centers. Besides training, robotic devices can overcome some of the limitations in traditional clinical assessments by providing more objective, sensitive, reliable and time-efficient measurements. However, it is necessary to understand the clinical needs to be able to develop novel robot-aided assessment methods that can be integrated in clinical practice.This paper aims at providing researchers and developers in the field of robotic neurorehabilitation with a comprehensive review of assessment methods for the lower extremities. Among the ICF domains, we included those related to lower extremities sensorimotor functions and walking; for each chapter we present and discuss existing assessments used in routine clinical practice and contrast those to state-of-the-art instrumented and robot-aided technologies. Based on the shortcomings of current assessments, on the identified clinical needs and on the opportunities offered by robotic devices, we propose future directions for research in rehabilitation robotics. The review and recommendations provided in this paper aim to guide the design of the next generation of robot-aided functional assessments, their validation and their translation to clinical practice. PMID:27485106

  18. Event Detection and Spatial Analysis for Characterizing Extreme Precipitation

    NASA Astrophysics Data System (ADS)

    Jeon, S.; Prabhat, M.; Byna, S.; Collins, W.; Wehner, M. F.

    2013-12-01

    Atmospheric Rivers (ARs) are large spatially coherent weather systems with high concentrations of elevated water vapor that often cause severe downpours and flooding over western coastal United States. With the availability of more atmospheric moisture in the future under global warming, we expect ARs to play an important role as a potential cause of extreme precipitation. We have recently developed TECA software for automatically identifying and tracking features in climate datasets. In particular, we are able to identify ARs that make landfall on the western coast of North America. This detection tool examines integrated water vapor field above a certain threshold and performs geometric analysis. Based on the detection procedure, we investigate impacts of ARs by exploring spatial extent of AR precipitation for CMIP5 simulations, and characterize spatial pattern of dependence for future projections under climate change within the framework of extreme value theory. The results show that AR events in RCP8.5 scenario (2076-2100) tend to produce heavier rainfall with higher frequency and longer duration than the events from historical run (1981-2005). Range of spatial dependence between extreme precipitations is concentrated on smaller localized area in California under the highest emission scenario than present day. Preliminary results are illustrated in Figure 1 and 2. Fig 1: Boxplot of annual max precipitation (left two) and max AR precipitation (right two) from GFDL-ESM2M during 25-year time period by station in California, US. Fig 2: Spatial dependence of max AR precipitation calculated from Station 4 (triangle) for historical run (left) and for future projections of RCP8.5 (right) from GFDL-ESM2M. Green and orange colors represent complete dependence and independence between two stations respectively.

  19. Extreme Scale Computing for First-Principles Plasma Physics Research

    SciTech Connect

    Chang, Choogn-Seock

    2011-10-12

    World superpowers are in the middle of the “Computnik” race. US Department of Energy (and National Nuclear Security Administration) wishes to launch exascale computer systems into the scientific (and national security) world by 2018. The objective is to solve important scientific problems and to predict the outcomes using the most fundamental scientific laws, which would not be possible otherwise. Being chosen into the next “frontier” group can be of great benefit to a scientific discipline. An extreme scale computer system requires different types of algorithms and programming philosophy from those we have been accustomed to. Only a handful of scientific codes are blessed to be capable of scalable usage of today’s largest computers in operation at petascale (using more than 100,000 cores concurrently). Fortunately, a few magnetic fusion codes are competing well in this race using the “first principles” gyrokinetic equations.These codes are beginning to study the fusion plasma dynamics in full-scale realistic diverted device geometry in natural nonlinear multiscale, including the large scale neoclassical and small scale turbulence physics, but excluding some ultra fast dynamics. In this talk, most of the above mentioned topics will be introduced at executive level. Representative properties of the extreme scale computers, modern programming exercises to take advantage of them, and different philosophies in the data flows and analyses will be presented. Examples of the multi-scale multi-physics scientific discoveries made possible by solving the gyrokinetic equations on extreme scale computers will be described. Future directions into “virtual tokamak experiments” will also be discussed.

  20. 27 CFR 478.112 - Importation by a licensed importer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Importation § 478.112 Importation by a licensed importer. (a) No firearm, firearm barrel, or ammunition shall... the Director has authorized the importation of the firearm, firearm barrel, or ammunition. (b)(1) An application for a permit, ATF Form 6—Part I, to import or bring a firearm, firearm barrel, or ammunition...

  1. The role of synoptic and intraseasonal anomalies in the life cycle of summer rainfall extremes over South America

    NASA Astrophysics Data System (ADS)

    Hirata, Fernando E.; Grimm, Alice M.

    2016-05-01

    The main goal of this study is to describe the role of synoptic and intraseasonal anomalies during the life cycle of summer rainfall extremes over South America. Eastward-propagating synoptic-scale midlatitude waves are the main drivers of extreme precipitation events south of the Amazon and their interaction with intraseasonal anomalies over South America is important for heavy rainfall over the South Atlantic convergence zone (SACZ) region and the La Plata basin. Madden-Julian Oscillation (MJO) convective activity in the western Pacific (phases 6 and 7) leads 31 out of 81 extremes over the SACZ region by nearly 10 days. The connection between the MJO and rainfall extremes in other regions is less robust. During El Niño seasons extremes are more frequent in the La Plata basin, with decreased importance of intraseasonal anomalies. Precipitation extremes over the La Plata basin tend to be less frequent and also shorter during La Niña summers and, consequently, less hazardous. In the SACZ and the southeastern Brazilian coast, heavy rainfall is also more frequent under El Niño conditions, while La Niña episodes also increase extreme events in the southeastern coast. Extremes over the southeastern coast during El Niños are favored by strong intraseasonal anomalies flanking the subtropical jet, while during La Niñas intraseasonal anomalies are not significant.

  2. North American extreme temperature events and related large scale meteorological patterns: A review of statistical methods, dynamics, modeling, and trends

    SciTech Connect

    Grotjahn, Richard; Black, Robert; Leung, Ruby; Wehner, Michael F.; Barlow, Mathew; Bosilovich, Michael; Gershunov, Alexander; Gutowski, Jr., William J.; Gyakum, John R.; Katz, Richard W.; Lee, Yun -Young; Lim, Young -Kwon; Prabhat, -

    2015-05-22

    This paper reviews research approaches and open questions regarding data, statistical analyses, dynamics, modeling efforts, and trends in relation to temperature extremes. Our specific focus is upon extreme events of short duration (roughly less than 5 days) that affect parts of North America. These events are associated with large scale meteorological patterns (LSMPs). Methods used to define extreme events statistics and to identify and connect LSMPs to extreme temperatures are presented. Recent advances in statistical techniques can connect LSMPs to extreme temperatures through appropriately defined covariates that supplements more straightforward analyses. A wide array of LSMPs, ranging from synoptic to planetary scale phenomena, have been implicated as contributors to extreme temperature events. Current knowledge about the physical nature of these contributions and the dynamical mechanisms leading to the implicated LSMPs is incomplete. There is a pressing need for (a) systematic study of the physics of LSMPs life cycles and (b) comprehensive model assessment of LSMP-extreme temperature event linkages and LSMP behavior. Generally, climate models capture the observed heat waves and cold air outbreaks with some fidelity. However they overestimate warm wave frequency and underestimate cold air outbreaks frequency, and underestimate the collective influence of low-frequency modes on temperature extremes. Climate models have been used to investigate past changes and project future trends in extreme temperatures. Overall, modeling studies have identified important mechanisms such as the effects of large-scale circulation anomalies and land-atmosphere interactions on changes in extreme temperatures. However, few studies have examined changes in LSMPs more specifically to understand the role of LSMPs on past and future extreme temperature changes. Even though LSMPs are resolvable by global and regional climate models, they are not necessarily well simulated so more

  3. North American extreme temperature events and related large scale meteorological patterns: A review of statistical methods, dynamics, modeling, and trends

    DOE PAGESBeta

    Grotjahn, Richard; Black, Robert; Leung, Ruby; Wehner, Michael F.; Barlow, Mathew; Bosilovich, Michael; Gershunov, Alexander; Gutowski, Jr., William J.; Gyakum, John R.; Katz, Richard W.; et al

    2015-05-22

    This paper reviews research approaches and open questions regarding data, statistical analyses, dynamics, modeling efforts, and trends in relation to temperature extremes. Our specific focus is upon extreme events of short duration (roughly less than 5 days) that affect parts of North America. These events are associated with large scale meteorological patterns (LSMPs). Methods used to define extreme events statistics and to identify and connect LSMPs to extreme temperatures are presented. Recent advances in statistical techniques can connect LSMPs to extreme temperatures through appropriately defined covariates that supplements more straightforward analyses. A wide array of LSMPs, ranging from synoptic tomore » planetary scale phenomena, have been implicated as contributors to extreme temperature events. Current knowledge about the physical nature of these contributions and the dynamical mechanisms leading to the implicated LSMPs is incomplete. There is a pressing need for (a) systematic study of the physics of LSMPs life cycles and (b) comprehensive model assessment of LSMP-extreme temperature event linkages and LSMP behavior. Generally, climate models capture the observed heat waves and cold air outbreaks with some fidelity. However they overestimate warm wave frequency and underestimate cold air outbreaks frequency, and underestimate the collective influence of low-frequency modes on temperature extremes. Climate models have been used to investigate past changes and project future trends in extreme temperatures. Overall, modeling studies have identified important mechanisms such as the effects of large-scale circulation anomalies and land-atmosphere interactions on changes in extreme temperatures. However, few studies have examined changes in LSMPs more specifically to understand the role of LSMPs on past and future extreme temperature changes. Even though LSMPs are resolvable by global and regional climate models, they are not necessarily well simulated so

  4. Do climate extreme events foster violent civil conflicts? A coincidence analysis

    NASA Astrophysics Data System (ADS)

    Schleussner, Carl-Friedrich; Donges, Jonathan F.; Donner, Reik V.

    2014-05-01

    Civil conflicts promoted by adverse environmental conditions represent one of the most important potential feedbacks in the global socio-environmental nexus. While the role of climate extremes as a triggering factor is often discussed, no consensus is yet reached about the cause-and-effect relation in the observed data record. Here we present results of a rigorous statistical coincidence analysis based on the Munich Re Inc. extreme events database and the Uppsala conflict data program. We report evidence for statistically significant synchronicity between climate extremes with high economic impact and violent conflicts for various regions, although no coherent global signal emerges from our analysis. Our results indicate the importance of regional vulnerability and might aid to identify hot-spot regions for potential climate-triggered violent social conflicts.

  5. Radiative heat transfer in the extreme near field.

    PubMed

    Kim, Kyeongtae; Song, Bai; Fernández-Hurtado, Víctor; Lee, Woochul; Jeong, Wonho; Cui, Longji; Thompson, Dakotah; Feist, Johannes; Reid, M T Homer; García-Vidal, Francisco J; Cuevas, Juan Carlos; Meyhofer, Edgar; Reddy, Pramod

    2015-12-17

    Radiative transfer of energy at the nanometre length scale is of great importance to a variety of technologies including heat-assisted magnetic recording, near-field thermophotovoltaics and lithography. Although experimental advances have enabled elucidation of near-field radiative heat transfer in gaps as small as 20-30 nanometres (refs 4-6), quantitative analysis in the extreme near field (less than 10 nanometres) has been greatly limited by experimental challenges. Moreover, the results of pioneering measurements differed from theoretical predictions by orders of magnitude. Here we use custom-fabricated scanning probes with embedded thermocouples, in conjunction with new microdevices capable of periodic temperature modulation, to measure radiative heat transfer down to gaps as small as two nanometres. For our experiments we deposited suitably chosen metal or dielectric layers on the scanning probes and microdevices, enabling direct study of extreme near-field radiation between silica-silica, silicon nitride-silicon nitride and gold-gold surfaces to reveal marked, gap-size-dependent enhancements of radiative heat transfer. Furthermore, our state-of-the-art calculations of radiative heat transfer, performed within the theoretical framework of fluctuational electrodynamics, are in excellent agreement with our experimental results, providing unambiguous evidence that confirms the validity of this theory for modelling radiative heat transfer in gaps as small as a few nanometres. This work lays the foundations required for the rational design of novel technologies that leverage nanoscale radiative heat transfer.

  6. Dual Domain Material Point Method for Materials in Extreme

    NASA Astrophysics Data System (ADS)

    Zhang, Duan; Dhakal, Tilak

    Dual domain material point method is the latest version of the material point method designed to overcome many numerical difficulties of the original material point method with an increased numerical accuracy. In this talk, after reviewing the numerical theory of the method, we apply this method to cases involving extreme material deformation, shock propagation, and pulverization based on continuum theories. We will compare this method to other similar particle methods, and then examine the applicability and needed modification of the continuum theory for cases involving strong thermodynamic non-equilibrium. The history of the material deformation is often important in such systems. We will explore the Lagrangian capability brought by the use of particles in the dual domain material point method and introduce a multiscale scheme taking advantages of the particle-mesh communications in the method to study history dependent thermodynamically non-equilibrium systems, caused by extreme material deformations, such as hypervelocity impact and shock loading. We will also discuss the history tracking capability, analyze numerical advantages and difficulties, and show the results obtained from this numerical scheme. Work supported by ASC project of LANL.

  7. Climate change and hydrological extremes in Belgian catchments

    NASA Astrophysics Data System (ADS)

    Baguis, P.; Roulin, E.; Willems, P.; Ntegeka, V.

    2010-07-01

    In this study we focus our attention on the climate change impacts on the hydrological balance in Belgium. There are two main rivers in the country, the Scheldt and the Meuse, supplied with water almost exclusively by precipitation. With the climate change projected by climate models for the end of the current century, one would expect that the hydrological regime of the rivers may be affected mainly through the changes in precipitation patterns and the increased potential evapotranspiration (PET) due to increased temperature throughout the year. We examine the hydrology of two important tributaries of the rivers Scheldt and Meuse, the Gete and the Ourthe, respectively. Our analysis is based on simulations with the SCHEME hydrological model and on climate change data from the European PRUDENCE project. Two emission scenarios are considered, the SRES A2 and B2 scenarios, and the perturbation (or delta) method is used in order to assess the climate change signal at monthly time scale and provide appropriate input time series for the hydrological simulations. The ensemble of climate change scenarios used allows us to estimate the combined model and scenario uncertainty in the streamflow calculations, inherent to this kind of analysis. In this context, we also analyze extreme river flows using two probability distribution families, allowing us to quantify the shift of the extremes under climate change conditions.

  8. Damage detection in mechanical structures using extreme value statistic.

    SciTech Connect

    Worden, K.; Allen, D. W.; Sohn, H.; Farrar, C. R.

    2002-01-01

    The first and most important objective of any damage identification algorithms is to ascertain with confidence if damage is present or not. Many methods have been proposed for damage detection based on ideas of novelty detection founded in pattern recognition and multivariate statistics. The philosophy of novelty detection is simple. Features are first extracted from a baseline system to be monitored, and subsequent data are then compared to see if the new features are outliers, which significantly depart from the rest of population. In damage diagnosis problems, the assumption is that outliers are generated from a damaged condition of the monitored system. This damage classification necessitates the establishment of a decision boundary. Choosing this threshold value is often based on the assumption that the parent distribution of data is Gaussian in nature. While the problem of novelty detection focuses attention on the outlier or extreme values of the data i.e. those points in the tails of the distribution, the threshold selection using the normality assumption weighs the central population of data. Therefore, this normality assumption might impose potentially misleading behavior on damage classification, and is likely to lead the damage diagnosis astray. In this paper, extreme value statistics is integrated with the novelty detection to specifically model the tails of the distribution of interest. Finally, the proposed technique is demonstrated on simulated numerical data and time series data measured from an eight degree-of-freedom spring-mass system.

  9. X-ray diffraction at Matter in Extreme Conditions endstation

    NASA Astrophysics Data System (ADS)

    Xing, Zhou; Galtier, Eric; Lee, Hae Ja; Nagler, Bob

    2015-11-01

    Understanding dynamic response at the atomic level under extreme conditions is highly sought after goal to science frontiers studying warm dense matter, high pressure, geoscience, astrophysics, and planetary science. Thus it is of importance to determine the high pressure phases or metastable phases of material under shock compression. In situ X-ray diffraction technique using LCLS free electron laser X-ray is a powerful tool to record structural behavior and microstructure evolution in dense matter. Shock-induced compression and phase transitions of material lead to changes of the lattice spacing or evolution of new X-ray diffraction patterns. In this talk, we describe a platform dedicated for the X-ray diffraction studies at Matter in Extreme Conditions (MEC), which can be used to reconstruct a complete diffraction pattern from numerous detectors, optimize detector positioning in a timely manner, extract the lattice spacing profiles and texture features. This platform is available to the user community for real-time analysis. We will also discuss experimental results, using this platform, on the crystalline silicon phase transitions up to 60 GPa.

  10. Characterization of Multilayer Reflective Coatings for Extreme Ultraviolet Lithography

    SciTech Connect

    Wedowski, M.; Gullikson, E.M.; Underwood, J.H.; Spiller, E.A.; Montcalm, C.; Kearney, P.A.; Bajt, S.; Schmidt, M.A.; Folta, J.A.

    1999-11-01

    The synchrotron-based reflectometer at beamline 6.3.2 of the Advanced Light Source (ALS) in Berkeley is an important metrology tool within the current Extreme Ultraviolet Lithography (EUVL) program. This program is a joint activity of three National Laboratories and a consortium of leading semiconductor manufacturers. Its goal is the development of a technology for routine production of sub-100 nm feature sizes for microelectronic circuits. Multilayer-coated normal-incidence optical surfaces reflecting in the Extreme Ultraviolet (EUV) spectral range near 13 nm are the basis for this emerging technology. All optical components of EUV lithographic steppers need to be characterized at-wavelength during their development and manufacturing process. Multilayer coating uniformity and gradient, accurate wavelength matching and high peak reflectances are the main parameters to be optimized. The mechanical and optical properties of the reflectometer at ALS beamline 6.3.2 proved to be well suited for the needs of the current EUVL program. In particular the facility is highly precise in its wavelength calibration and the determination of absolute EUV reflectance. The reproducibility of results of measurements at ALS beamline 6.3.2 is 0.2 % for reflectivity and 0.002 nm for wavelength.

  11. Demographic effects of extreme winter weather in the barn owl.

    PubMed

    Altwegg, Res; Roulin, Alexandre; Kestenholz, Matthias; Jenni, Lukas

    2006-08-01

    Extreme weather events can lead to immediate catastrophic mortality. Due to their rare occurrence, however, the long-term impacts of such events for ecological processes are unclear. We examined the effect of extreme winters on barn owl (Tyto alba) survival and reproduction in Switzerland over a 68-year period (approximately 20 generations). This long-term data set allowed us to compare events that occurred only once in several decades to more frequent events. Winter harshness explained 17 and 49% of the variance in juvenile and adult survival, respectively, and the two harshest winters were associated with major population crashes caused by simultaneous low juvenile and adult survival. These two winters increased the correlation between juvenile and adult survival from 0.63 to 0.69. Overall, survival decreased non-linearly with increasing winter harshness in adults, and linearly in juveniles. In contrast, brood size was not related to the harshness of the preceding winter. Our results thus reveal complex interactions between climate and demography. The relationship between weather and survival observed during regular years is likely to underestimate the importance of climate variation for population dynamics. PMID:16645855

  12. Atomic and electronic structures of an extremely fragile liquid

    PubMed Central

    Kohara, Shinji; Akola, Jaakko; Patrikeev, Leonid; Ropo, Matti; Ohara, Koji; Itou, Masayoshi; Fujiwara, Akihiko; Yahiro, Jumpei; Okada, Junpei T.; Ishikawa, Takehiko; Mizuno, Akitoshi; Masuno, Atsunobu; Watanabe, Yasuhiro; Usuki, Takeshi

    2014-01-01

    The structure of high-temperature liquids is an important topic for understanding the fragility of liquids. Here we report the structure of a high-temperature non-glass-forming oxide liquid, ZrO2, at an atomistic and electronic level. The Bhatia–Thornton number–number structure factor of ZrO2 does not show a first sharp diffraction peak. The atomic structure comprises ZrO5, ZrO6 and ZrO7 polyhedra with a significant contribution of edge sharing of oxygen in addition to corner sharing. The variety of large oxygen coordination and polyhedral connections with short Zr–O bond lifetimes, induced by the relatively large ionic radius of zirconium, disturbs the evolution of intermediate-range ordering, which leads to a reduced electronic band gap and increased delocalization in the ionic Zr–O bonding. The details of the chemical bonding explain the extremely low viscosity of the liquid and the absence of a first sharp diffraction peak, and indicate that liquid ZrO2 is an extremely fragile liquid. PMID:25520236

  13. eXtreme Adaptive Optics Planet Imager: Overview and status

    SciTech Connect

    Macintosh, B A; Bauman, B; Evans, J W; Graham, J; Lockwood, C; Poyneer, L; Dillon, D; Gavel, D; Green, J; Lloyd, J; Makidon, R; Olivier, S; Palmer, D; Perrin, M; Severson, S; Sheinis, A; Sivaramakrishnan, A; Sommargren, G; Soumer, R; Troy, M; Wallace, K; Wishnow, E

    2004-08-18

    As adaptive optics (AO) matures, it becomes possible to envision AO systems oriented towards specific important scientific goals rather than general-purpose systems. One such goal for the next decade is the direct imaging detection of extrasolar planets. An 'extreme' adaptive optics (ExAO) system optimized for extrasolar planet detection will have very high actuator counts and rapid update rates - designed for observations of bright stars - and will require exquisite internal calibration at the nanometer level. In addition to extrasolar planet detection, such a system will be capable of characterizing dust disks around young or mature stars, outflows from evolved stars, and high Strehl ratio imaging even at visible wavelengths. The NSF Center for Adaptive Optics has carried out a detailed conceptual design study for such an instrument, dubbed the eXtreme Adaptive Optics Planet Imager or XAOPI. XAOPI is a 4096-actuator AO system, notionally for the Keck telescope, capable of achieving contrast ratios >10{sup 7} at angular separations of 0.2-1'. ExAO system performance analysis is quite different than conventional AO systems - the spatial and temporal frequency content of wavefront error sources is as critical as their magnitude. We present here an overview of the XAOPI project, and an error budget highlighting the key areas determining achievable contrast. The most challenging requirement is for residual static errors to be less than 2 nm over the controlled range of spatial frequencies. If this can be achieved, direct imaging of extrasolar planets will be feasible within this decade.

  14. Experiments on extreme states of matter towards HIF at FAIR

    NASA Astrophysics Data System (ADS)

    Sharkov, Boris; Varentsov, Dmitry

    2014-01-01

    The Facility for Antiproton and Ion Research in Europe (FAIR) will provide worldwide unique accelerator and experimental facilities allowing for a large variety of unprecedented frontier research in extreme state of matter physics and applied science. Indeed, it is the largest basic research project on the roadmap of the European Strategy Forum of Research Infrastructures (ESFRI), and it is cornerstone of the European Research Area. FAIR offers to scientists from the whole world an abundance of outstanding research opportunities, broader in scope than any other contemporary large-scale facility worldwide. More than 2500 scientists are involved in setting up and exploiting the FAIR facility. They will push the frontiers of our knowledge in plasma, nuclear, atomic, hadron and applied physics far ahead, with important implications also for other fields in science such as cosmology, astro and particle physics, and technology. It includes 14 initial experiments, which form the four scientific pillars of FAIR. The main thrust of intense heavy ion and laser beam-matter interaction research focuses on the structure and evolution of extreme state of matter on both a microscopic and on a cosmic scale.

  15. Experiments on extreme states of matter towards HIF at FAIR

    NASA Astrophysics Data System (ADS)

    Sharkov, Boris; Varentsov, Dmitry

    2013-11-01

    The Facility for Antiproton and Ion Research in Europe (FAIR) will provide worldwide unique accelerator and experimental facilities allowing for a large variety of unprecedented frontier research in extreme state of matter physics and applied science. Indeed, it is the largest basic research project on the roadmap of the European Strategy Forum of Research Infrastructures (ESFRI), and it is cornerstone of the European Research Area. FAIR offers to scientists from the whole world an abundance of outstanding research opportunities, broader in scope than any other contemporary large-scale facility worldwide. More than 2500 scientists are involved in setting up and exploiting the FAIR facility. They will push the frontiers of our knowledge in plasma, nuclear, atomic, hadron and applied physics far ahead, with important implications also for other fields in science such as cosmology, astro and particle physics, and technology. It includes 14 initial experiments, which form the four scientific pillars of FAIR. The main thrust of intense heavy ion and laser beam-matter interaction research focuses on the structure and evolution of extreme state of matter on both a microscopic and on a cosmic scale.

  16. Extreme adaptations for aquatic ectoparasitism in a Jurassic fly larva

    PubMed Central

    Chen, Jun; Wang, Bo; Engel, Michael S; Wappler, Torsten; Jarzembowski, Edmund A; Zhang, Haichun; Wang, Xiaoli; Zheng, Xiaoting; Rust, Jes

    2014-01-01

    The reconstruction of ancient insect ectoparasitism is challenging, mostly because of the extreme scarcity of fossils with obvious ectoparasitic features such as sucking-piercing mouthparts and specialized attachment organs. Here we describe a bizarre fly larva (Diptera), Qiyia jurassica gen. et sp. nov., from the Jurassic of China, that represents a stem group of the tabanomorph family Athericidae. Q. jurassica exhibits adaptations to an aquatic habitat. More importantly, it preserves an unusual combination of features including a thoracic sucker with six radial ridges, unique in insects, piercing-sucking mouthparts for fluid feeding, and crocheted ventral prolegs with upward directed bristles for anchoring and movement while submerged. We demonstrate that Q. jurassica was an aquatic ectoparasitic insect, probably feeding on the blood of salamanders. The finding reveals an extreme morphological specialization of fly larvae, and broadens our understanding of the diversity of ectoparasitism in Mesozoic insects. DOI: http://dx.doi.org/10.7554/eLife.02844.001 PMID:24963142

  17. Extreme inundation flows during the Hokkaido-Nansei-Oki Tsunami

    NASA Astrophysics Data System (ADS)

    Titov, Vasily V.; Synolakis, Costas Emmanuel

    The tsunami generated by the July 12, 1993 Hokkaido-Nansei-Oki Mw=7.8 earthquake produced in Japan the worst local tsunami-related death toll in fifty years, with estimated 10-18m/sec overland flow velocities and 30m runup. These extreme values are the largest recorded in Japan this century and are among the highest ever documented for non-landslide generated tsunamis. We model this event to confirm the estimated overland flow velocities, and we find that, given reasonable ground deformation data, current state-of-the-art shallow-water wave models can predict tsunami inundation correctly including extreme runup, current velocities and overland flow. We find that even small local topographic structures affect the runup to first-order, and that the resolution of the bathymetric data is more important than the grid resolution. Our results qualitatively suggest that—for this event—coastal inundation is more correlated with inundation velocities than with inundation heights, explaining also why threshold-type modeling has substantially underpredicted coastal inundation for this and other recent events.

  18. Extreme Spacecraft Charging in Polar Low Earth Orbit

    NASA Technical Reports Server (NTRS)

    Colson, Andrew D.; Minow, Joseph I.; NeergaardParker, Linda

    2012-01-01

    Spacecraft in low altitude, high inclination (including sun-synchronous) orbits are widely used for remote sensing of the Earth's land surface and oceans, monitoring weather and climate, communications, scientific studies of the upper atmosphere and ionosphere, and a variety of other scientific, commercial, and military applications. These systems episodically charge to frame potentials in the kilovolt range when exposed to space weather environments characterized by a high flux of energetic (10 s kilovolt) electrons in regions of low background plasma density which is similar in some ways to the space weather conditions in geostationary orbit responsible for spacecraft charging to kilovolt levels. We first review the physics of space environment interactions with spacecraft materials that control auroral charging rates and the anticipated maximum potentials that should be observed on spacecraft surfaces during disturbed space weather conditions. We then describe how the theoretical values compare to the observational history of extreme charging in auroral environments. Finally, a set of extreme DMSP charging events are described varying in maximum negative frame potential from 0.6 kV to 2 kV, focusing on the characteristics of the charging events that are of importance both to the space system designer and to spacecraft operators. The goal of the presentation is to bridge the gap between scientific studies of auroral charging and the need for engineering teams to understand how space weather impacts both spacecraft design and operations for vehicles on orbital trajectories that traverse auroral charging environments.

  19. Extreme Spacecraft Charging in Polar Low Earth Orbit

    NASA Technical Reports Server (NTRS)

    Colson, Andrew D.; Minow, Joseph I.; Parker, L. Neergaard

    2012-01-01

    Spacecraft in low altitude, high inclination (including sun -synchronous) orbits are widely used for remote sensing of the Earth fs land surface and oceans, monitoring weather and climate, communications, scientific studies of the upper atmosphere and ionosphere, and a variety of other scientific, commercial, and military applications. These systems episodically charge to frame potentials in the kilovolt range when exposed to space weather environments characterized by a high flux of energetic (approx.10 fs kilovolt) electrons in regions of low background plasma density. Auroral charging conditions are similar in some ways to the space weather conditions in geostationary orbit responsible for spacecraft charging to kilovolt levels. We first review the physics of space environment interactions with spacecraft materials that control auroral charging rates and the anticipated maximum potentials that should be observed on spacecraft surfaces during disturbed space weather conditions. We then describe how the theoretical values compare to the observational history of extreme charging in auroral environments. Finally, a set of extreme DMSP charging events are described varying in maximum negative frame potential from approx.0.6 kV to approx.2 kV, focusing on the characteristics of the charging events that are of importance both to the space system designer and to spacecraft operators. The goal of the presentation is to bridge the gap between scientific studies of auroral charging and the need for engineering teams to understand how space weather impacts both spacecraft design and operations for vehicles on orbital trajectories that traverse auroral charging environments.

  20. Extreme Spacecraft Charging in Polar Low Earth Orbit

    NASA Astrophysics Data System (ADS)

    Colson, A.; Minow, J. I.; Parker, L.

    2012-12-01

    Spacecraft in low altitude, high inclination (including sun-synchronous) orbits are widely used for remote sensing of the Earth's land surface and oceans, monitoring weather and climate, communications, scientific studies of the upper atmosphere and ionosphere, and a variety of other scientific, commercial, and military applications. These systems episodically charge to frame potentials in the kilovolt range when exposed to space weather environments characterized by a high flux of energetic (~10's kilovolt) electrons in regions of low background plasma density which is similar in some ways to the space weather conditions in geostationary orbit responsible for spacecraft charging to kilovolt levels. We first review the physics of space environment interactions with spacecraft materials that control auroral charging rates and the anticipated maximum potentials that should be observed on spacecraft surfaces during disturbed space weather conditions. We then describe how the theoretical values compare to the observational history of extreme charging in auroral environments. Finally, a set of extreme DMSP charging events are described varying in maximum negative frame potential from ~0.6 kV to ~2 kV, focusing on the characteristics of the charging events that are of importance both to the space system designer and to spacecraft operators. The goal of the presentation is to bridge the gap between scientific studies of auroral charging and the need for engineering teams to understand how space weather impacts both spacecraft design and operations for vehicles on orbital trajectories that traverse auroral charging environments.