Science.gov

Sample records for mitigating resisting forces

  1. Will black carbon mitigation dampen aerosol indirect forcing?

    NASA Astrophysics Data System (ADS)

    Chen, W.-T.; Lee, Y. H.; Adams, P. J.; Nenes, A.; Seinfeld, J. H.

    2010-05-01

    If mitigation of black carbon (BC) particulate matter is accompanied by a decrease in particle number emissions, and thereby by a decrease in global cloud condensation nuclei (CCN) concentrations, a decrease in global cloud radiative forcing (a reverse “cloud albedo effect”) results. We consider two present-day mitigation scenarios: 50% reduction of primary black carbon/organic carbon (BC/OC) mass and number emissions from fossil fuel combustion (termed HF), and 50% reduction of primary BC/OC mass and number emissions from all primary carbonaceous sources (fossil fuel, domestic biofuel, and biomass burning) (termed HC). Radiative forcing effects of these scenarios are assessed through present-day equilibrium climate simulations. Global average top-of-the-atmosphere changes in radiative forcing for the two scenarios, relative to present day conditions, are +0.13 ± 0.33 W m-2 (HF) and + 0.31 ± 0.33 W m-2 (HC).

  2. Force protection and infectious risk mitigation from suicide bombers.

    PubMed

    Clint, Brandon D

    2009-07-01

    Pedestrian suicide bombers (SB) pose an infectious threat to United States (U.S.) forces. The objective of this study is to evaluate the use of rapid human immunodeficiency virus (HIV) antibody assays under contaminated field conditions and develop plans to mitigate the infectious threat. Twenty-six commercially available rapid HIV antibody assays were contaminated with environmental substances. Half of the tests were conducted with HIV-1 antibody (Ab) positive controls and half with HIV Ab negative controls. There were no test failures. Using statistical approximations to evaluate the plausibility of a zero failure rate, the upper 95% confidence limit for the occurrence of a test failure by chance is at most 10.8%. These results suggest the test's success is less likely because of chance and further studies should be conducted for validation. Regardless of the methodology, it is important to develop plans to mitigate infectious risks from pedestrian suicide bombers.

  3. Combating antibiotic resistance, mitigating future threats and ongoing initiatives.

    PubMed

    Velez, Roseann; Sloand, Elizabeth

    2016-07-01

    To emphasise the impact of antibiotic resistance as a persistent, global health threat and highlight efforts to improve this complex problem. Political agendas, legislation, development of therapies and educational initiatives are essential to mitigate the increasing rate of antibiotic resistance. Original manuscript. Prescribers, policymakers and researchers are charged with the complex task of mitigating antibiotic resistance in an era when new treatments for bacterial infections are limited. Monitoring, surveillance and incentivising of practice, policy and new treatments provide solutions to antibiotic resistance in both the human and agricultural sectors. This article emphasises the complexity of antibiotic resistance and highlights the need for a multifaceted approach to improve health care outcomes. © 2016 John Wiley & Sons Ltd.

  4. Mitigated-force carriage for high magnetic field environments

    SciTech Connect

    Ludtka, Gerard M.; Ludtka, Gail M.; Wilgen, John B.; Murphy, Bart L.

    2015-05-19

    A carriage for high magnetic field environments includes a plurality of work-piece separators disposed in an operable relationship with a work-piece processing magnet having a magnetic field strength of at least 1 Tesla for supporting and separating a plurality of work-pieces by a preselected, essentially equal spacing, so that, as a first work-piece is inserted into the magnetic field, a second work-piece is simultaneously withdrawn from the magnetic field, so that an attractive magnetic force imparted on the first work-piece offsets a resistive magnetic force imparted on the second work-piece.

  5. Myths, models and mitigation of resistance to pesticides.

    PubMed Central

    Hoy, M A

    1998-01-01

    Resistance to pesticides in arthropod pests is a significant economic, ecological and public health problem. Although extensive research has been conducted on diverse aspects of pesticide resistance and we have learned a great deal during the past 50 years, to some degree the discussion about 'resistance management' has been based on 'myths'. One myth involves the belief that we can manage resistance. I will maintain that we can only attempt to mitigate resistance because resistance is a natural evolutionary response to environmental stresses. As such, resistance will remain an ongoing dilemma in pest management and we can only delay the onset of resistance to pesticides. 'Resistance management' models and tactics have been much discussed but have been tested and deployed in practical pest management programmes with only limited success. Yet the myth persists that better models will provide a 'solution' to the problem. The reality is that success in using mitigation models is limited because these models are applied to inappropriate situations in which the critical genetic, ecological, biological or logistic assumptions cannot be met. It is difficult to predict in advance which model is appropriate to a particular situation; if the model assumptions cannot be met, applying the model sometimes can increase the rate of resistance development rather than slow it down. Are there any solutions? I believe we already have one. Unfortunately, it is not a simple or easy one to deploy. It involves employing effective agronomic practices to develop and maintain a healthy crop, monitoring pest densities, evaluating economic injury levels so that pesticides are applied only when necessary, deploying and conserving biological control agents, using host-plant resistance, cultural controls of the pest, biorational pest controls, and genetic control methods. As a part of a truly multi-tactic strategy, it is crucial to evaluate the effect of pesticides on natural enemies in order to

  6. Mitigated-force carriage for high magnetic field environments

    SciTech Connect

    Ludtka, Gerard M; Ludtka, Gail M; Wilgen, John B; Murphy, Bart L

    2014-05-20

    A carriage for high magnetic field environments includes a first work-piece holding means for holding a first work-piece, the first work-piece holding means being disposed in an operable relationship with a work-piece processing magnet having a magnetic field strength of at least 1 Tesla. The first work-piece holding means is further disposed in operable connection with a second work-piece holding means for holding a second work-piece so that, as the first work-piece is inserted into the magnetic field, the second work-piece is simultaneously withdrawn from the magnetic field, so that an attractive magnetic force imparted on the first work-piece offsets a resistive magnetic force imparted on the second work-piece.

  7. Hyper-resistive forced magnetic reconnection

    SciTech Connect

    Vekstein, G.

    2016-02-15

    We study Taylor's model of forced magnetic reconnection mediated by plasma hyper-resistivity. This includes both linear and nonlinear regimes of the process. It is shown how the onset of plasmoid instability occurs in the strongly nonlinear regime of forced reconnection.

  8. A Constant-Force Resistive Exercise Unit

    NASA Technical Reports Server (NTRS)

    Colosky, Paul; Ruttley, Tara

    2010-01-01

    A constant-force resistive exercise unit (CFREU) has been invented for use in both normal gravitational and microgravitational environments. In comparison with a typical conventional exercise machine, this CFREU weighs less and is less bulky: Whereas weight plates and associated bulky supporting structures are used to generate resistive forces in typical conventional exercise machines, they are not used in this CFREU. Instead, resistive forces are generated in this CFREU by relatively compact, lightweight mechanisms based on constant-torque springs wound on drums. Each such mechanism is contained in a module, denoted a resistive pack, that includes a shaft for making a torque connection to a cable drum. During a stroke of resistive exercise, the cable is withdrawn from the cable drum against the torque exerted by the resistance pack. The CFREU includes a housing, within which can be mounted one or more resistive pack(s). The CFREU also includes mechanisms for engaging any combination of (1) one or more resistive pack(s) and (2) one or more spring(s) within each resistive pack to obtain a desired level of resistance.

  9. Mitigating Resistance to Teaching Science Through Inquiry: Studying Self

    NASA Astrophysics Data System (ADS)

    Spector, Barbara; Burkett, Ruth S.; Leard, Cyndy

    2007-04-01

    This is the report of a qualitative emergent-design study of 2 different Web-enhanced science methods courses for preservice elementary teachers in which an experiential learning strategy, labeled “using yourself as a learning laboratory,” was implemented. Emergent grounded theory indicated this strategy, when embedded in a course organized as an inquiry with specified action foci, contributed to mitigating participants’ resistance to learning and teaching through inquiry. Enroute to embracing inquiry, learners experienced stages resembling the stages of grief one experiences after a major loss. Data sources included participant observation, electronic artifacts in WebCT, and interviews. Findings are reported in 3 major sections: “Action Foci Common to Both Courses,” “Participants’ Growth and Change,” and “Challenges and Tradeoffs.”

  10. Aligned composite structures for mitigation of impact damage and resistance to wear in dynamic environments

    DOEpatents

    Mulligan, Anthony C.; Rigali, Mark J.; Sutaria, Manish P.; Popovich, Dragan; Halloran, Joseph P.; Fulcher, Michael L.; Cook, Randy C.

    2005-12-13

    Fibrous monolith composites having architectures that provide increased flaw insensitivity, improved hardness, wear resistance and damage tolerance and methods of manufacture thereof are provided for use in dynamic environments to mitigate impact damage and increase wear resistance.

  11. Aligned composite structures for mitigation of impact damage and resistance to wear in dynamic environments

    DOEpatents

    Mulligan, Anthony C.; Rigali, Mark J.; Sutaria, Manish P.; Popovich, Dragan; Halloran, Joseph P.; Fulcher, Michael L.; Cook, Randy C.

    2009-04-14

    Fibrous monolith composites having architectures that provide increased flaw insensitivity, improved hardness, wear resistance and damage tolerance and methods of manufacture thereof are provided for use in dynamic environments to mitigate impact damage and increase wear resistance.

  12. Aligned composite structures for mitigation of impact damage and resistance to wear in dynamic environments

    DOEpatents

    Rigali, Mark J.; Sutaria, Manish P.; Mulligan, Anthony C.; Popovich, Dragan

    2004-03-23

    Fibrous monolith composites having architectures that provide increased flaw insensitivity, improved hardness, wear resistance and damage tolerance and methods of manufacture thereof are provided for use in dynamic environments to mitigate impact damage and increase wear resistance.

  13. An Assessment of Molecular Dynamic Force Fields for Silica for Use in Simulating Laser Damage Mitigation

    SciTech Connect

    Soules, T F; Gilmer, G H; Matthews, M J; Stolken, J S; Feit, M D

    2010-10-21

    We compare force fields (FF's) that have been used in molecular dynamic (MD) simulations of silica in order to assess their applicability for use in simulating IR-laser damage mitigation. Although pairwise FF?s obtained by fitting quantum mechanical calculations such as the BKS and CHIK potentials have been shown to reproduce many of the properties of silica including the stability of silica polymorphs and the densification of the liquid, we show that melting temperatures and fictive temperatures are much too high. Softer empirical force fields give liquid and glass properties at experimental temperatures but may not predict all properties important to laser mitigation experiments.

  14. Resistance of plants to gravitational force.

    PubMed

    Soga, Kouichi

    2013-09-01

    Developing resistance to gravitational force is a critical response for terrestrial plants to survive under 1 × g conditions. We have termed this reaction "gravity resistance" and have analyzed its nature and mechanisms using hypergravity conditions produced by centrifugation and microgravity conditions in space. Our results indicate that plants develop a short and thick body and increase cell wall rigidity to resist gravitational force. The modification of body shape is brought about by the rapid reorientation of cortical microtubules that is caused by the action of microtubule-associated proteins in response to the magnitude of the gravitational force. The modification of cell wall rigidity is regulated by changes in cell wall metabolism that are caused by alterations in the levels of cell wall enzymes and in the pH of apoplastic fluid (cell wall fluid). Mechanoreceptors on the plasma membrane may be involved in the perception of the gravitational force. In this review, we discuss methods for altering gravitational conditions and describe the nature and mechanisms of gravity resistance in plants.

  15. Short-Lived Climate Forcers - The Connections Between Emissions, Forcing, and Mitigation Potential (Invited)

    NASA Astrophysics Data System (ADS)

    Smith, S.

    2010-12-01

    Methane, tropospheric ozone, and aerosols have a substantial global and regional influence on climate in addition to the impact of ozone and aerosols on health and ecosystems. These climate forcing agents are linked both though common emissions sources and atmospheric chemical processes. The magnitude and regional distribution of these forcings have changed substantially over the past and is expected to continue to change into the future. While aerosols have had a substantial impact on climate over the past century, by the end of the 21st century aerosols will likely be only a minor contributor to radiative forcing. Overall, reductions in aerosol emissions lead to a net warming due to the net negative aerosol forcing, although some mitigation benefits may be possible in specific sub-sectors. While the emissions leading to enhanced tropospheric ozone levels are short-lived, mitigation has proved to be difficult due to the ubiquity of major emission sources, particularly surface transportation vehicles. From a mitigation standpoint, therefore, tropospheric ozone might be considered as more of a long-term pollutant. This presentation will review these links using historical data and future projections and discuss the implications for mitigation. The implications of these links for atmospheric chemistry analysis, and the potential for using ACC-MIP results to improve integrated assessment modeling and analysis, will be discussed.

  16. Guidance on Radon Resistant Construction and Radon Mitigation

    EPA Pesticide Factsheets

    This Unnumbered Letter regarding radon gas mitigation applies to all housing and community facilities, low-rise buildings and dwellings for the mentioned programs. Its intention is to guide staff to best serve our borrowers and protect their health.

  17. Fabrication of mitigation pits for improving laser damage resistance in dielectric mirrors by femtosecond laser machining

    SciTech Connect

    Wolfe, Justin E.; Qiu, S. Roger; Stolz, Christopher J.

    2011-03-20

    Femtosecond laser machining is used to create mitigation pits to stabilize nanosecond laser-induced damage in multilayer dielectric mirror coatings on BK7 substrates. In this paper, we characterize features and the artifacts associated with mitigation pits and further investigate the impact of pulse energy and pulse duration on pit quality and damage resistance. Our results show that these mitigation features can double the fluence-handling capability of large-aperture optical multilayer mirror coatings and further demonstrate that femtosecond laser macromachining is a promising means for fabricating mitigation geometry in multilayer coatings to increase mirror performance under high-power laser irradiation.

  18. CO2 and non-CO2 radiative forcings in climate projections for twenty-first century mitigation scenarios

    NASA Astrophysics Data System (ADS)

    Strassmann, Kuno M.; Plattner, G.-K.; Joos, F.

    2009-11-01

    Climate is simulated for reference and mitigation emissions scenarios from Integrated Assessment Models using the Bern2.5CC carbon cycle-climate model. Mitigation options encompass all major radiative forcing agents. Temperature change is attributed to forcings using an impulse-response substitute of Bern2.5CC. The contribution of CO2 to global warming increases over the century in all scenarios. Non-CO2 mitigation measures add to the abatement of global warming. The share of mitigation carried by CO2, however, increases when radiative forcing targets are lowered, and increases after 2000 in all mitigation scenarios. Thus, non-CO2 mitigation is limited and net CO2 emissions must eventually subside. Mitigation rapidly reduces the sulfate aerosol loading and associated cooling, partly masking Greenhouse Gas mitigation over the coming decades. A profound effect of mitigation on CO2 concentration, radiative forcing, temperatures and the rate of climate change emerges in the second half of the century.

  19. Towards a Comprehensive Strategy to Mitigate Dissemination of Environmental Sources of Antibiotic Resistance.

    PubMed

    Vikesland, Peter J; Pruden, Amy; Alvarez, Pedro J J; Aga, Diana S; Buergmann, Helmut; Li, Xiangdong; Manaia, Célia M; Nambi, Indumathi M; Wigginton, Krista R; Zhang, Tong; Zhu, Yong-Guan

    2017-10-04

    Antibiotic resistance is a pervasive global health threat. To combat the spread of resistance, it is necessary to consider all possible sources and understand the pathways and mechanisms by which resistance disseminates. Best management practices are urgently needed to provide barriers to the spread of resistance and maximize the lifespan of antibiotics as a precious resource. Herein we advise upon the need for coordinated national and international strategies, highlighting three essential components: 1) Monitoring, 2) Risk Assessment, and 3) Mitigation of antibiotic resistance. Central to all three components is What exactly to monitor, assess, and mitigate? We address this question within an environmental framework, drawing from fundamental microbial ecological processes driving the spread of resistance.

  20. Sensitivity of Space Launch System Buffet Forcing Functions to Buffet Mitigation Options

    NASA Technical Reports Server (NTRS)

    Piatak, David J.; Sekula, Martin K.; Rausch, Russ D.

    2016-01-01

    Time-varying buffet forcing functions arise from unsteady aerodynamic pressures and are one of many load environments, which contribute to the overall loading condition of a launch vehicle during ascent through the atmosphere. The buffet environment is typically highest at transonic conditions and can excite the vehicle dynamic modes of vibration. The vehicle response to these buffet forcing functions may cause high structural bending moments and vibratory environments, which can exceed the capabilities of the structure, or of vehicle components such as payloads and avionics. Vehicle configurations, protuberances, payload fairings, and large changes in stage diameter can trigger undesirable buffet environments. The Space Launch System (SLS) multi-body configuration and its structural dynamic characteristics presented challenges to the load cycle design process with respect to buffet-induced loads and responses. An initial wind-tunnel test of a 3-percent scale SLS rigid buffet model was conducted in 2012 and revealed high buffet environments behind the booster forward attachment protuberance, which contributed to reduced vehicle structural margins. Six buffet mitigation options were explored to alleviate the high buffet environments including modified booster nose cones and fences/strakes on the booster and core. These studies led to a second buffet test program that was conducted in 2014 to assess the ability of the buffet mitigation options to reduce buffet environments on the vehicle. This paper will present comparisons of buffet forcing functions from each of the buffet mitigation options tested, with a focus on sectional forcing function rms levels within regions of the vehicle prone to high buffet environments.

  1. Mitigating Insider Sabotage and Espionage: A Review of the United States Air Force’s Current Posture

    DTIC Science & Technology

    2009-03-01

    THE UNITED STATES AIR FORCE’S CURRENT POSTURE THESIS Erika C. Leach, Captain, USAF AFIT/ GIR /ENG/09-05 DEPARTMENT OF THE AIR FORCE AIR...the United States Air Force, Department of Defense, or the United States Government. AFIT/ GIR /ENG/09-05 MITIGATING INSIDER SABOTAGE AND...Leach, BA Captain, USAF March 2009 APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. AFIT/ GIR /ENG/09-05 MITIGATING INSIDER

  2. (-)-Epicatechin mitigates high fructose-associated insulin resistance by modulating redox signaling and endoplasmic reticulum stress

    PubMed Central

    Bettaieb, Ahmed; Vazquez Prieto, Marcela A.; Rodriguez Lanzi, Cecilia; Miatello, Roberto M.; Haj, Fawaz G.; Fraga, César G.; Oteiza, Patricia I.

    2014-01-01

    We investigated the capacity of dietary (-)-epicatechin (EC) to mitigate insulin resistance through the modulation of redox-regulated mechanisms in a rat model of metabolic syndrome (MetS). Adolescent rats were fed a regular chow diet without or with high fructose (HFr) (10% (w/v)) in drinking water for 8 weeks, and a group of HFr-fed rats was supplemented with EC in the diet. HFr-fed rats developed insulin resistance which was mitigated by EC supplementation. Accordingly, the activation of components of the insulin signaling cascade (insulin receptor (IR), IRS-1, Akt and ERK1/2) was impaired, while negative regulators (PKC, IKK, JNK and PTP1B) were upregulated in the liver and adipose tissue of HFr rats. These alterations were partially or totally prevented by EC supplementation. In addition, EC inhibited events which contribute to insulin resistance: HFr-associated increased expression and activity of NADPH oxidase, activation of redox-sensitive signals, expression of NF-κB-regulated pro-inflammatory cytokines and chemokines, and some sub-arms of endoplasmic reticulum stress signaling. Collectively, these findings indicate that EC supplementation can mitigate HFr-induced insulin resistance and are relevant to define interventions that can prevent/mitigate MetS-associated insulin resistance. PMID:24746618

  3. (-)-Epicatechin mitigates high-fructose-associated insulin resistance by modulating redox signaling and endoplasmic reticulum stress.

    PubMed

    Bettaieb, Ahmed; Vazquez Prieto, Marcela A; Rodriguez Lanzi, Cecilia; Miatello, Roberto M; Haj, Fawaz G; Fraga, César G; Oteiza, Patricia I

    2014-07-01

    We investigated the capacity of dietary (-)-epicatechin (EC) to mitigate insulin resistance through the modulation of redox-regulated mechanisms in a rat model of metabolic syndrome. Adolescent rats were fed a regular chow diet without or with high fructose (HFr; 10% w/v) in drinking water for 8 weeks, and a group of HFr-fed rats was supplemented with EC in the diet. HFr-fed rats developed insulin resistance, which was mitigated by EC supplementation. Accordingly, the activation of components of the insulin signaling cascade (insulin receptor, IRS1, Akt, and ERK1/2) was impaired, whereas negative regulators (PKC, IKK, JNK, and PTP1B) were upregulated in the liver and adipose tissue of HFr rats. These alterations were partially or totally prevented by EC supplementation. In addition, EC inhibited events that contribute to insulin resistance: HFr-associated increased expression and activity of NADPH oxidase, activation of redox-sensitive signals, expression of NF-κB-regulated proinflammatory cytokines and chemokines, and some sub-arms of endoplasmic reticulum stress signaling. Collectively, these findings indicate that EC supplementation can mitigate HFr-induced insulin resistance and are relevant for defining interventions that can prevent/mitigate MetS-associated insulin resistance.

  4. Searching for optimal mitigation geometries for laser resistant multilayer high reflector coatings

    SciTech Connect

    Qiu, S R; Wolfe, J E; Monterrosa, A M; Feit, M D; Pistor, T V; STolz, C J

    2011-02-11

    Growing laser damage sites on multilayer high reflector coatings can limit mirror performance. One of the strategies to improve laser damage resistance is to replace the growing damage sites with pre-designed benign mitigation structures. By mitigating the weakest site on the optic, the large aperture mirror will have a laser resistance comparable to the intrinsic value of the multilayer coating. To determine the optimal mitigation geometry, the finite difference time domain method (FDTD) was used to quantify the electric-field intensification within the multilayer, at the presence of different conical pits. We find that the field intensification induced by the mitigation pit is strongly dependent on the polarization and the angle of incidence (AOI) of the incoming wave. Therefore the optimal mitigation conical pit geometry is application specific. Furthermore, our simulation also illustrates an alternative means to achieve an optimal mitigation structure by matching the cone angle of the structure with the AOI of the incoming wave, except for the p-polarization wave at a range of incident angles between 30{sup o} and 45{sup o}.

  5. Quantification of User and Manufacturer Variabilities in Urinary Catheter Anchoring Balloon Inflation and Mitigation of Variability by Flow Resistance.

    PubMed

    Davis, Niall F; Cunnane, Eoghan M; Mooney, Rory C; Manecksha, Rustom P; Thornhill, John A; Walsh, Michael T

    2017-04-01

    To quantify user variability and manufacturer variability in urinary catheter anchoring balloon inflation pressure and to mitigate any significant variance by incorporating flow resistance into the anchoring balloon inflation process. Inflation of a urinary catheter anchoring balloon was performed at atmospheric pressure by different users (n = 8) to investigate user variability. A calibrated pressure transducer measured inflation pressures, and a video extensometer measured balloon inflation profiles. Manufacturer variability was investigated by applying constant forces to the plunger of conventional syringes to mimic "heavy-," "intermediate-," and "light"-handed users for 3 brands of catheter. Flow restrictors of variable reduced cross-sectional areas were introduced to the outflow of the inflation syringes to investigate the effect of flow resistance on anchoring balloon inflation profiles. Variations in maximum inflation pressures (range: 75-355 kPa) were observed among the different users. There were no significant differences in maximum inflation pressure between brands at any of the 3 simulated hand forces (P = .97). Increasing the flow resistance significantly reduces the applicable inflation pressure of all hand forces (P < .001). Specifically, the difference in inflation pressure between heavy- and light-handed forces is reduced from over 405 kPa to under 65 kPa. Introducing flow resistance does not result in a significant difference in inflation pressure between brands (P = .254). There is significant user variability in urinary catheter balloon inflation pressure. This variation can be significantly reduced by introducing flow resistance to the inflation technique. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Effects of equivalent series resistance on the noise mitigation performance of piezoelectric shunt damping

    NASA Astrophysics Data System (ADS)

    Lai, Szu Cheng; Sharifzadeh Mirshekarloo, Meysam; Yao, Kui

    2017-05-01

    Piezoelectric shunt damping (PSD) utilizes an electrically-shunted piezoelectric damper attached on a panel structure to suppress the transmission of acoustic noise. The paper develops an understanding on the effects of equivalent series resistance (ESR) of the piezoelectric damper in a PSD system on noise mitigation performance, and demonstrates that an increased ESR leads to a significant rise in the noise transmissibility due to reduction in the system’s mechanical damping. It is further demonstrated with experimental results that ESR effects can be compensated in the shunt circuit to significantly improve the noise mitigation performance. A theoretical electrical equivalent model of the PSD incorporating the ESR is established for quantitative analysis of ESR effects on noise mitigation.

  7. Comprehensive radiative forcing assesment highlights trade-offs in climate mitigation potential of managed boreal forests

    NASA Astrophysics Data System (ADS)

    Kalliokoski, Tuomo; Berninger, Frank; Bäck, Jaana; Boy, Michael; Kuusinen, Nea; Mäkelä, Annikki; Matthies, Brent; Minkkinen, Kari; Mogensen, Ditte; Peltoniemi, Mikko; Sievänen, Risto; Zhou, Luxi; Vanhatalo, Anni; Valsta, Lauri; Nikinmaa, Eero

    2016-04-01

    Boreal forests have an important role in the mitigation of climate change. In this study we evaluated four key climate impacts of forest management: (1) carbon sequestration (in forest ecosystems and wood products), (2) surface albedo of forest area, (3) forest originating Secondary Organic Aerosols (SOA) and (4) avoided CO2-emissions from wood energy and product substitution. We calculated their net effect at both a single stand and regional level using Finland as a case study. We made analyses both in current climate up to a year 2050 and in the projected climate of year 2050. At the stand level, the carbon sequestration effect and avoided CO2 emissions due to substituted materials dominated in net RF in current climate. The warming effect of surface albedo of forest cover was lower or of same magnitude than cooling effect of SOAs. Together, the rarely considered SOAs and product substitution corresponded over 70% of the total cooling effect of forest cover. The cooling effect of net radiative forcing increased along the increasing site fertility. Although the carbon stocks of broadleaved trees were smaller than that of conifers their total radiative cooling effect was larger due to the integrated albedo and aerosol effects. In the projected climate of 2050, the radiative cooling of aerosols approached the level of forest carbon fixation. These results emphasize the need for holistic evaluation of climate impacts over simple carbon sequestration analysis to understand the role of forest management in climate change mitigation. Landscape level analyses emphasized the broad range of options to reach the cooling effect. The lowest harvest regime, 50% of current annual increment (CAI), yielded the largest cooling effect. Yet, harvests up to CAI produced only slightly less cooling RF if avoided emissions were considered. This result was highly sensitive to used substitution factors. Our result highlights that the combination of intensive harvests and the use of wood

  8. On the resistive diffusion of force-free magnetic fields

    NASA Technical Reports Server (NTRS)

    Low, B. C.

    1980-01-01

    Reid and Laing (1979) conjectured on the general behavior of resistive force-free magnetic fields in a slab model following a numerical study. However, the basic properties of resistive force-free magnetic fields had been established previously. Some results from the previous work are extended to show that the conjecture of Reid and Laing is incorrect. A general analytic treatment of the problem provides the correct physical properties that Reid and Laing were unable to deduce from their numerical solutions. A criticism is also given of the results presented in another numerical study treating cylindrical resistive force-free magnetic fields, by the same authors.

  9. Effects of resistance training on force steadiness and common drive.

    PubMed

    Beck, Travis W; Defreitas, Jason M; Stock, Matt S; Dillon, Michael A

    2011-02-01

    The purpose of this study was to investigate the influence of an 8-week resistance training program on force steadiness and common drive for the vastus lateralis muscle. Eight untrained men performed a resistance training program. Before the program and at the end of each week, the subjects performed a trapezoid isometric muscle action of the leg extensors, and bipolar surface electromyographic signals were recorded from the vastus lateralis. The signals were decomposed into action potential trains that were cross-correlated to measure common drive. Force steadiness was quantified as the standard deviation of force during the constant-force portion of the trapezoid muscle action. The training program did not consistently affect force steadiness or common drive for any of the subjects. Although future studies are needed with different muscles and training programs, changes in the overall motor control scheme are not likely with resistance training.

  10. Identifying potential ground movement as a landslide mitigation approach using resistivity method

    NASA Astrophysics Data System (ADS)

    Izzati, F. N.; Laksmana, Z. S.; Marcelina, B.; Hutabarat, S. S.; Widodo

    2017-07-01

    Landslide is defined as a form of ground movement in which land mass suddenly fails downward on a slope as aresult of gravitational pull. One of the mitigative approaches into investigating landslide is to identify a potential slip zone usingresistivity method. In this study, the array chosen to acquire the resistivity data was Wenner array as it provides a robust resolution in mapping lateral resistivity variations. This method will generate a contour map portraying thedistribution of resistivity values of the subsurface. Beforehand, a 2-dimensional forward modeling was conducted to acquire anexpected ideal result of possible potential slip zone. Landslides itself are affiliated with a low resistivity zone that is locatedbetween two high resistivity zones. This study is conducted in a ground slump in Jalan Citra Green, Northern Bandung which is comprised of mostly unconsolidated soil. By applying a least-square inversion to the resistivity data obtained, resistivity values of 10-200 Ωm is attained. Based on the inversion result, a low resistivity zone of 10-20 Ωm is identified spanning from the surface to approximately 10 meters deep. In conclusion, furtherinvestigations are needed to determine whether the low resistivity zone is associated with potential slip zone as our datais limited to a single line

  11. A resistive force model for complex intrusion in granular media

    NASA Astrophysics Data System (ADS)

    Zhang, Tingnan; Li, Chen; Goldman, Daniel

    2012-11-01

    Intrusion forces in granular media (GM) are best understood for simple shapes (like disks and rods) undergoing vertical penetration and horizontal drag. Inspired by a resistive force theory for sand-swimming, we develop a new two-dimensional resistive force model for intruders of arbitrary shape and intrusion path into GM in the vertical plane. We divide an intruder of complex geometry into small segments and approximate segmental forces by measuring forces on small flat plates in experiments. Both lift and drag forces on the plates are proportional to penetration depth, and depend sensitively on the angle of attack and the direction of motion. Summation of segmental forces over the intruder predicts the net forces on a c-leg, a flat leg, and a reversed c-leg rotated into GM about a fixed axle. The stress profiles are similar for GM of different particle sizes, densities, coefficients of friction, and volume fractions. We propose a universal scaling law applicable to all tested GM. By combining the new force model with a multi-body simulator, we can also predict the locomotion dynamics of a small legged robot on GM. Our force laws can provide a strict test of hydrodynamic-like approaches to model dense granular flows. Also affiliated to: School of Physics, Georgia Institute of Technology.

  12. Capability of new multi-segment winding configurations in HTS transformer to mitigate electromagnetic forces under short-circuit condition

    NASA Astrophysics Data System (ADS)

    Ghabeli, Asef; Besmi, Mohammad Reza

    2017-06-01

    The consequences of short-circuit forces for high-temperature superconductor (HTS) transformers are much more detrimental than conventional ones. That is because on one hand, HTS windings have less mechanical robustness than copper ones and on the other hand, the effects of extreme axial forces on HTS windings are irreversible and may cause irreparable damages to HTS transformers. In this paper, capability of new concentric multi-segment winding configurations in HTS transformers, proposed in Ghabeli et al. (2015), to mitigate high axial and radial electromagnetic forces due to short-circuit fault is investigated. The studied winding configurations include concentric PSP (Primary-Secondary-Primary), symmetrical and asymmetrical PSPSP (Primary-Secondary-Primary-Secondary-Primary). The study is realized with an advanced numerical method using accurate and nonlinear E-J power law via FEM-based software Flux 2D. Profiles of axial and radial electromagnetic forces in each sub-winding have been presented, analyzed and compared to each other in detail. For accurate calculation of axial and radial forces in each sub-winding, a collection of points along the longitudinal and transverse axes in the center of each sub-winding was considered. The maximum of radial and axial electromagnetic forces decrease remarkably in PSPSP winding configuration compared to PSP winding configuration. In addition, the asymmetrical winding configurations mitigate these forces more than symmetrical ones.

  13. Kinetic Ductility and Force-Spike Resistance of Proteins from Single-Molecule Force Spectroscopy.

    PubMed

    Cossio, Pilar; Hummer, Gerhard; Szabo, Attila

    2016-08-23

    Ductile materials can absorb spikes in mechanical force, whereas brittle ones fail catastrophically. Here we develop a theory to quantify the kinetic ductility of single molecules from force spectroscopy experiments, relating force-spike resistance to the differential responses of the intact protein and the unfolding transition state to an applied mechanical force. We introduce a class of unistable one-dimensional potential surfaces that encompass previous models as special cases and continuously cover the entire range from ductile to brittle. Compact analytic expressions for force-dependent rates and rupture-force distributions allow us to analyze force-clamp and force-ramp pulling experiments. We find that the force-transmitting protein domains of filamin and titin are kinetically ductile when pulled from their two termini, making them resistant to force spikes. For the mechanostable muscle protein titin, a highly ductile model reconciles data over 10 orders of magnitude in force loading rate from experiment and simulation. Copyright © 2016 Biophysical Society. All rights reserved.

  14. Lembang fault plane identification using electrical resistivity method for disaster mitigation

    NASA Astrophysics Data System (ADS)

    Maulinadya, S.; Ramadhan, M. Lutfi; N. Wening, F.; Pinehas, D.; Widodo

    2017-07-01

    Lembang Fault is an active fault lies from West to East located 10 kilometers in north of Bandung. It is a normal fault that its foot wall raises 40-450 meters above the ground. Its location that is not so far from Bandung, which is densely populated and frequently visited by tourists, makes Lembang Fault a threat if it becomes suddenly active. Its movement can cause earthquakes that can result in fatalities. Therefore, act of mitigation is necessary, such as educating people about Lembang Fault and its potential to cause disaster. The objective of this study is to find Lembang Fault plane below the surface with geo electrical mapping method and vertical elect rical sounding method around Ciwarega and The Peak, Lembang (west side of Lembang Fault). Both of these methods are using electricity current to measure rock resistivity. Currents are injected to the ground and potential differences are measured. According to Ohm's Law, resistivity can be calculated so that resistivity distribution can be obtained. In this study, high resistivity contrast is obtained; it is about 1400-5000 Ohm.m. This resistivity contrast can be caused by lateral lithology difference resulted by fault existence. This proves that there is actually a fault in Lembang that potentially cause disasters like earthquakes.

  15. Trehalose prevents adipocyte hypertrophy and mitigates insulin resistance in mice with established obesity.

    PubMed

    Arai, Chikako; Miyake, Masaki; Matsumoto, Yohsuke; Mizote, Akiko; Yoshizane, Chiyo; Hanaya, Yohko; Koide, Kazuhiro; Yamada, Mika; Hanaya, Toshiharu; Arai, Shigeyuki; Fukuda, Shigeharu

    2013-01-01

    Our group recently demonstrated that simultaneous administration of trehalose with a high-fat diet (HFD) suppresses adipocyte hypertrophy and mitigates insulin resistance in mice. For the present study, we hypothesized that similar effects of trehalose would be observed in mice with previously-established obesity. Obese mice were fed a HFD and drinking water containing 0.3 or 2.5% (weight/volume) trehalose or distilled water (DW) ad libitum for 8 wk. After 7 wk intake of a HFD and trehalose, fasting serum insulin levels and homeostasis model assessment-insulin resistance (HOMA-IR) in the 0.3% Tre/HFD group were significantly lower than those in the DW/HFD group (p<0.05). After 8 wk of treatment, mesenteric adipocytes in the 0.3% Tre/HFD group showed significantly less hypertrophy than those in the DW/HFD group. Mechanistic analysis indicated that levels of high molecular weight (HMW) adiponectin in the serum of the 0.3% Tre/HFD group were significantly higher than those in the DW/HFD group. The expression levels of insulin receptor substrate-1 (IRS-1) and insulin receptor substrate-2 (IRS-2) messenger RNA (mRNA) in muscle were also significantly increased by trehalose intake. Our data therefore suggest that administration of trehalose to obese mice mitigates insulin resistance by suppressing adipocyte hypertrophy and increasing serum HMW adiponectin, resulting in upregulation of IRS-1, and IRS-2 expression in muscle. These results further suggest that trehalose is a functional saccharide that may be used to prevent the progression of insulin resistance.

  16. Challenges and mitigation strategies for resist trim etch in resist-mandrel based SAQP integration scheme

    NASA Astrophysics Data System (ADS)

    Mohanty, Nihar; Franke, Elliott; Liu, Eric; Raley, Angelique; Smith, Jeffrey; Farrell, Richard; Wang, Mingmei; Ito, Kiyohito; Das, Sanjana; Ko, Akiteru; Kumar, Kaushik; Ranjan, Alok; O'Meara, David; Nawa, Kenjiro; Scheer, Steven; DeVillers, Anton; Biolsi, Peter

    2015-03-01

    Patterning the desired narrow pitch at 10nm technology node and beyond, necessitates employment of either extreme ultra violet (EUV) lithography or multi-patterning solutions based on 193nm-immersion lithography. With enormous challenges being faced in getting EUV lithography ready for production, multi-patterning solutions that leverage the already installed base of 193nm-immersion-lithography are poised to become the industry norm for 10 and 7nm technology nodes. For patterning sub-40nm pitch line/space features, self-aligned quadruple patterning (SAQP) with resist pattern as the first mandrel shows significant cost as well as design benefit, as compared to EUV lithography or other multi-patterning techniques. One of the most critical steps in this patterning scheme is the resist mandrel definition step which involves trimming / reformation of resist profile via plasma etch for achieving appropriate pitch after the final pattern. Being the first mandrel, the requirements for the Line Edge Roughness (LER) / Line Width Roughness (LWR); critical dimension uniformity (CDU); and profile in 3-dimensions for the resist trim / reformation etch is extremely aggressive. In this paper we highlight the unique challenges associated in developing resist trim / reformation plasma etch process for SAQP integration scheme and summarize our efforts in optimizing the trim etch chemistries, process steps and plasma etch parameters for meeting the mandrel definition targets. Finally, we have shown successful patterning of 30nm pitch patterns via the resist-mandrel SAQP scheme and its implementation for Si-fin formation at 7nm node.

  17. Antibiotic Cycling and Antibiotic Mixing: Which One Best Mitigates Antibiotic Resistance?

    PubMed

    Beardmore, Robert Eric; Peña-Miller, Rafael; Gori, Fabio; Iredell, Jonathan

    2017-04-01

    Can we exploit our burgeoning understanding of molecular evolution to slow the progress of drug resistance? One role of an infection clinician is exactly that: to foresee trajectories to resistance during antibiotic treatment and to hinder that evolutionary course. But can this be done at a hospital-wide scale? Clinicians and theoreticians tried to when they proposed two conflicting behavioral strategies that are expected to curb resistance evolution in the clinic, these are known as "antibiotic cycling" and "antibiotic mixing." However, the accumulated data from clinical trials, now approaching 4 million patient days of treatment, is too variable for cycling or mixing to be deemed successful. The former implements the restriction and prioritization of different antibiotics at different times in hospitals in a manner said to "cycle" between them. In antibiotic mixing, appropriate antibiotics are allocated to patients but randomly. Mixing results in no correlation, in time or across patients, in the drugs used for treatment which is why theorists saw this as an optimal behavioral strategy. So while cycling and mixing were proposed as ways of controlling evolution, we show there is good reason why clinical datasets cannot choose between them: by re-examining the theoretical literature we show prior support for the theoretical optimality of mixing was misplaced. Our analysis is consistent with a pattern emerging in data: neither cycling or mixing is a priori better than the other at mitigating selection for antibiotic resistance in the clinic. : antibiotic cycling, antibiotic mixing, optimal control, stochastic models.

  18. Early Detection and Mitigation of Resistance to Bt Maize by Western Corn Rootworm (Coleoptera: Chrysomelidae).

    PubMed

    Andow, David A; Pueppke, Steven G; Schaafsma, Arthur W; Gassmann, Aaron J; Sappington, Thomas W; Meinke, Lance J; Mitchell, Paul D; Hurley, Terrance M; Hellmich, Richard L; Porter, R Pat

    2016-02-01

    Transgenic Bt maize that produces less than a high-dose has been widely adopted and presents considerable insect resistance management (IRM) challenges. Western corn rootworm, Diabrotica virgifera virgifera LeConte, has rapidly evolved resistance to Bt maize in the field, leading to local loss of efficacy for some corn rootworm Bt maize events. Documenting and responding to this resistance has been complicated by a lack of rapid diagnostic bioassays and by regulatory triggers that hinder timely and effective management responses. These failures are of great concern to the scientific and agricultural community. Specific challenges posed by western corn rootworm resistance to Bt maize, and more general concerns around Bt crops that produce less than a high-dose of Bt toxin, have caused uncertainty around current IRM protocols. More than 15 years of experience with IRM has shown that high-dose and refuge-based IRM is not applicable to Bt crops that produce less than a high-dose. Adaptive IRM approaches and pro-active, integrated IRM-pest management strategies are needed and should be in place before release of new technologies that produce less than a high-dose. We suggest changes in IRM strategies to preserve the utility of corn rootworm Bt maize by 1) targeting local resistance management earlier in the sequence of responses to resistance and 2) developing area-wide criteria to address widespread economic losses. We also favor consideration of policies and programs to counteract economic forces that are contributing to rapid resistance evolution.

  19. Optimization of the Chin Bar of a Composite-Shell Helmet to Mitigate the Upper Neck Force

    NASA Astrophysics Data System (ADS)

    Farajzadeh Khosroshahi, S.; Galvanetto, U.; Ghajari, M.

    2016-11-01

    The chin bar of motorcycle full-face helmets is the most likely region of the helmet to sustain impacts during accidents, with a large percentage of these impacts leading to basilar skull fracture. Currently, helmet chin bars are designed to mitigate the peak acceleration at the centre of gravity of isolated headforms, as required by standards, but they are not designed to mitigate the neck force, which is probably the cause of basilar skull fracture, a type of head injury that can lead to fatalities. Here we test whether it is possible to increase the protection of helmet chin bars while meeting standard requirements. Fibre-reinforced composite shells are commonly used in helmets due to their lightweight and energy absorption characteristics. We optimize the ply orientation of a chin bar made of fibre-reinforced composite layers for reduction of the neck force in a dummy model using a computational approach. We use the finite element model of a human head/neck surrogate and measure the neck axial force, which has been shown to be correlated with the risk of basilar skull fracture. The results show that by varying the orientation of the chin bar plies, thus keeping the helmet mass constant, the neck axial force can be reduced by approximately 30% while ensuring that the helmet complies with the impact attenuation requirements prescribed in helmet standards.

  20. Optimization of the Chin Bar of a Composite-Shell Helmet to Mitigate the Upper Neck Force

    NASA Astrophysics Data System (ADS)

    Farajzadeh Khosroshahi, S.; Galvanetto, U.; Ghajari, M.

    2017-08-01

    The chin bar of motorcycle full-face helmets is the most likely region of the helmet to sustain impacts during accidents, with a large percentage of these impacts leading to basilar skull fracture. Currently, helmet chin bars are designed to mitigate the peak acceleration at the centre of gravity of isolated headforms, as required by standards, but they are not designed to mitigate the neck force, which is probably the cause of basilar skull fracture, a type of head injury that can lead to fatalities. Here we test whether it is possible to increase the protection of helmet chin bars while meeting standard requirements. Fibre-reinforced composite shells are commonly used in helmets due to their lightweight and energy absorption characteristics. We optimize the ply orientation of a chin bar made of fibre-reinforced composite layers for reduction of the neck force in a dummy model using a computational approach. We use the finite element model of a human head/neck surrogate and measure the neck axial force, which has been shown to be correlated with the risk of basilar skull fracture. The results show that by varying the orientation of the chin bar plies, thus keeping the helmet mass constant, the neck axial force can be reduced by approximately 30% while ensuring that the helmet complies with the impact attenuation requirements prescribed in helmet standards.

  1. Perceived causality, force, and resistance in the absence of launching.

    PubMed

    Hubbard, Timothy L; Ruppel, Susan E

    2017-04-01

    In the launching effect, a moving object (the launcher) contacts a stationary object (the target), and upon contact, the launcher stops and the target begins moving in the same direction and at the same or slower velocity as previous launcher motion (Michotte, 1946/1963). In the study reported here, participants viewed a modified launching effect display in which the launcher stopped before or at the moment of contact and the target remained stationary. Participants rated perceived causality, perceived force, and perceived resistance of the launcher on the target or the target on the launcher. For launchers and for targets, increases in the size of the spatial gap between the final location of the launcher and the location of the target decreased ratings of perceived causality and ratings of perceived force and increased ratings of perceived resistance. Perceived causality, perceived force, and perceived resistance exhibited gradients or fields extending from the launcher and from the target and were not dependent upon contact of the launcher and target. Causal asymmetries and force asymmetries reported in previous studies did not occur, and this suggests that such asymmetries might be limited to typical launching effect stimuli. Deviations from Newton's laws of motion are noted, and the existence of separate radii of action extending from the launcher and from the target is suggested.

  2. Gravity-independent constant force resistive exercise unit

    NASA Technical Reports Server (NTRS)

    Colosky, Jr., Paul E. (Inventor); Ruttley, Tara M. (Inventor)

    2004-01-01

    This invention describes a novel gravity-independent exercise unit designed for use in microgravity, or on the ground, as a means by which to counter muscle atrophy and bone degradation due to disuse or underuse. Modular resistive packs comprising constant torque springs provide constant force opposing the withdrawal of an exercise cable from the device. In addition to uses within the space program, the compact resistive packs of the CFREU allow the unit to be small enough for easy use as a home gym for personal use, or as a supplement for rehabilitation programs. Resistive packs may be changed conveniently out of the CFREU according to the desired exercise regimen. Thus, the resistive packs replace the need for expensive, heavy, and bulky traditional weight plates. The CFREU may be employed by hospitals, rehabilitation and physical therapy clinics, and other related professional businesses.

  3. A gravity-independent constant force resistive exercise unit.

    PubMed

    Ruttley, T M; Colosky, P E; James, S P

    2001-01-01

    This study designed, developed and tested a novel, practical, gravity-independent exercise machine, the Constant Force Resistance Exercise Unit (CFREU). A CFREU prototype was designed and built according to National Aeronautic and Space Administration (NASA) hardware and physiological requirements, and was evaluated for potential exercise countermeasure viability. Life cycle data exhibit lower life than required by NASA guidelines; however, current CFREU re-designs are addressing this issue. Electromyography (EMG) data indicate that the CFREU used on the ground and in microgravity during exercise is capable of providing forces on the muscles that are similar to a standard free-weight machine used in gravity. Given the results of this study, the CFREU has proven to be a viable potential resistive exercise countermeasure to the deconditioning of the musculoskeletal system in microgravity.

  4. Resistive and reactive force production in actuated elastic swimmers

    NASA Astrophysics Data System (ADS)

    Godoy-Diana, Ramiro; Pineirua, Miguel; Thiria, Benjamin

    2015-11-01

    We study the force production dynamics of undulating elastic plates as a model for fish-like inertial swimmers. Using a beam model coupled with Lighthill's large-amplitude elongated-body theory, we explore different localized actuations at one extremity of the plate (heaving, pitching, and a combination of both) in order to quantify the reactive and resistive contributions to the thrust. The latter has only recently been pointed out as a crucial element in the force balance of large Reynolds number swimmers. We show that this balance is modified as the frequency of excitation changes and the response of the elastic plate shifts between different resonant modes. In the heaving case for instance, higher frequencies and thus higher modes are associated to a stronger resistive contribution to the thrust, while in pitching case, at all frequencies, thrust production comes mostly from the reactive term. We acknowledge support from EADS foundation through project ``Fluids and elasticity in biomimetic propulsion''.

  5. Calcined Eggshell Waste for Mitigating Soil Antibiotic-Resistant Bacteria/Antibiotic Resistance Gene Dissemination and Accumulation in Bell Pepper.

    PubMed

    Ye, Mao; Sun, Mingming; Feng, Yanfang; Li, Xu; Schwab, Arthur P; Wan, Jinzhong; Liu, Manqiang; Tian, Da; Liu, Kuan; Wu, Jun; Jiang, Xin

    2016-07-13

    The combined accumulation of antibiotics, heavy metals, antibiotic-resistant bacteria (ARB)/antibiotic resistance genes (ARGs) in vegetables has become a new threat to human health. This is the first study to investigate the feasibility of calcined eggshells modified by aluminum sulfate as novel agricultural wastes to impede mixed contaminants from transferring to bell pepper (Capsicum annuum L.). In this work, calcined eggshell amendment mitigated mixed pollutant accumulation in bell pepper significantly, enhanced the dissipation of soil tetracycline, sulfadiazine, roxithromycin, and chloramphenicol, decreased the water-soluble fractions of antibiotics, and declined the diversity of ARB/ARGs inside the vegetable. Moreover, quantitative polymerase chain reaction analysis detected that ARG levels in the bell pepper fruits significantly decreased to 10(-10) copies/16S copies, indicating limited risk of ARGs transferring along the food chain. Furthermore, the restoration of soil microbial biological function suggests that calcined eggshell is an environmentally friendly amendment to control the dissemination of soil ARB/ARGs in the soil-vegetable system.

  6. Osmotic force resisting chain insertion in a colloidal suspension

    NASA Astrophysics Data System (ADS)

    Castelnovo, M.; Bowles, R. K.; Reiss, H.; Gelbart, W. M.

    2003-02-01

    We consider the problem of inserting a stiff chain into a colloidal suspension of particles that interact with it through excluded volume forces. The free energy of insertion is associated with the work of creating a cavity devoid of colloid and sufficiently large to accommodate the chain. The corresponding work per unit length is the force that resists the entry of the chain into the colloidal suspension. In the case of a hard sphere fluid, this work can be calculated straightforwardly within the scaled particle theory; for solutions of flexible polymers, on the other hand, we employ simple scaling arguments. The forces computed in these ways are shown, for nanometer chain and colloid diameters, to be of the order of tens of pN for solution volume fractions of a few tenths. These magnitudes are argued to be important for biophysical processes such as the ejection of DNA from viral capsids into the cell cytoplasm.

  7. The effectiveness of resistive force theory in granular locomotiona)

    NASA Astrophysics Data System (ADS)

    Zhang, Tingnan; Goldman, Daniel I.

    2014-10-01

    Resistive force theory (RFT) is often used to analyze the movement of microscopic organisms swimming in fluids. In RFT, a body is partitioned into infinitesimal segments, each of which generates thrust and experiences drag. Linear superposition of forces from elements over the body allows prediction of swimming velocities and efficiencies. We show that RFT quantitatively describes the movement of animals and robots that move on and within dry granular media (GM), collections of particles that display solid, fluid, and gas-like features. RFT works well when the GM is slightly polydisperse, and in the "frictional fluid" regime such that frictional forces dominate material inertial forces, and when locomotion can be approximated as confined to a plane. Within a given plane (horizontal or vertical) relationships that govern the force versus orientation of an elemental intruder are functionally independent of the granular medium. We use the RFT to explain features of locomotion on and within granular media including kinematic and muscle activation patterns during sand-swimming by a sandfish lizard and a shovel-nosed snake, optimal movement patterns of a Purcell 3-link sand-swimming robot revealed by a geometric mechanics approach, and legged locomotion of small robots on the surface of GM. We close by discussing situations to which granular RFT has not yet been applied (such as inclined granular surfaces), and the advances in the physics of granular media needed to apply RFT in such situations.

  8. Does cryptic microbiota mitigate pine resistance to an invasive beetle-fungus complex? Implications for invasion potential.

    PubMed

    Cheng, Chihang; Xu, Letian; Xu, Dandan; Lou, Qiaozhe; Lu, Min; Sun, Jianghua

    2016-09-13

    Microbial symbionts are known to assist exotic pests in their colonization of new host plants. However, there has been little evidence linking symbiotic invasion success to mechanisms for mitigation of native plant resistance. The red turpentine beetle (RTB) was introduced with a fungus, Leptographium procerum, to China from the United States and became a destructively invasive symbiotic complex in natural Pinus tabuliformis forests. Here, we report that three Chinese-resident fungi, newly acquired by RTB in China, induce high levels of a phenolic defensive chemical, naringenin, in pines. This invasive beetle-fungus complex is suppressed by elevated levels of naringenin. However, cryptic microbiotas in RTB galleries strongly degrade naringenin, and pinitol, the main soluble carbohydrate of P. tabuliformis, is retained in L. procerum-infected phloem and facilitate naringenin biodegradation by the microbiotas. These results demonstrate that cryptic microbiota mitigates native host plant phenolic resistance to an invasive symbiotic complex, suggesting a putative mechanism for reduced biotic resistance to symbiotic invasion.

  9. Visco-Resistive MHD Modeling Benchmark of Forced Magnetic Reconnection

    NASA Astrophysics Data System (ADS)

    Beidler, M. T.; Hegna, C. C.; Sovinec, C. R.; Callen, J. D.; Ferraro, N. M.

    2016-10-01

    The presence of externally-applied 3D magnetic fields can affect important phenomena in tokamaks, including mode locking, disruptions, and edge localized modes. External fields penetrate into the plasma and can lead to forced magnetic reconnection (FMR), and hence magnetic islands, on resonant surfaces if the local plasma rotation relative to the external field is slow. Preliminary visco-resistive MHD simulations of FMR in a slab geometry are consistent with theory. Specifically, linear simulations exhibit proper scaling of the penetrated field with resistivity, viscosity, and flow, and nonlinear simulations exhibit a bifurcation from a flow-screened to a field-penetrated, magnetic island state as the external field is increased, due to the 3D electromagnetic force. These results will be compared to simulations of FMR in a circular cross-section, cylindrical geometry by way of a benchmark between the NIMROD and M3D-C1 extended-MHD codes. Because neither this geometry nor the MHD model has the physics of poloidal flow damping, the theory of will be expanded to include poloidal flow effects. The resulting theory will be tested with linear and nonlinear simulations that vary the resistivity, viscosity, flow, and external field. Supported by OFES DoE Grants DE-FG02-92ER54139, DE-FG02-86ER53218, DE-AC02-09CH11466, and the SciDAC Center for Extended MHD Modeling.

  10. To mitigate, resist, or undo: addressing structural influences on the health of urban populations.

    PubMed Central

    Geronimus, A T

    2000-01-01

    Young to middle-aged residents of impoverished urban areas suffer extra-ordinary rates of excess mortality, to which deaths from chronic disease contribute heavily. Understanding of urban health disadvantages and attempts to reverse them will be incomplete if the structural factors that produced modern minority ghettos in central cities are not taken into account. Dynamic conceptions of the role of race/ethnicity in producing health inequalities must encompass (1) social relationship between majority and minority populations that privilege the majority population and (2) the autonomous institutions within minority populations that members develop and sustain to mitigate, resist, or undo the adverse effects of discrimination. Broad social and economic policies that intensify poverty or undermine autonomous protections can reap dire consequences for health. Following from this structural analysis and previous research, guiding principles for action and suggestions for continued research are proposed. Without taking poverty and race/ethnicity into account, public health professionals who hope to redress the health problems of urban life risk exaggerating the returns that can be expected of public health campaigns or overlooking important approaches for mounting successful interventions. PMID:10846503

  11. Mechanical forces imposed on echinoid eggs during spawning: mitigation of forces by fibrous networks within egg extracellular layers.

    PubMed

    Thomas, F; Bolton, T; Sastry, A

    2001-03-01

    Many echinoderms spawn large numbers of eggs in rapid spawning bouts directly into the water column. During spawning, the eggs pass from the gonad along a narrow oviduct and through a rigid gonopore before reaching the water. As the eggs traverse this pathway, they are exposed to shear stress induced by the development of a velocity gradient within the fluid formed by the eggs. In some species, the diameter of the eggs is larger than the diameter of the gonopore. In these cases, the eggs also experience strain resulting from compression of the egg as it passes through the relatively small gonopore. The magnitude of shear stress experienced by eggs differs among species depending upon the viscosity of the eggs. The degree of strain experienced by eggs differs among species depending upon the relative sizes of the egg and gonopore and also changes within species as they grow. Recent evidence suggests that these forces have the propensity to damage eggs, thereby reducing their fertilizability, or to destroy them. Experimental evidence shows that the jelly coat around the eggs can protect them from shear stresses and reduce the strain imposed on them under a compressive force. Echinoderm eggs are surrounded by a jelly coat that has a composite structure of irregularly arranged fibrous networks embedded in a jelly matrix. These fibrous networks have characteristics that are similar to those of engineered and biological materials that are known to reduce the transmission of mechanical forces to other structures. Given this similarity to other materials, three possible mechanisms for the action of the jelly coat may be identified. First, the apparent viscosity of the eggs of echinoids declines as the rate at which they are sheared during spawning increases. This reduction in viscosity with increasing shear rate (shear-thinning) may, in part, be due to the structure of the jelly coat and its resultant non-Newtonian nature. Second, experimental evidence indicates that the

  12. Impacts of future air pollution mitigation strategies on the aerosol direct radiative forcing over Europe

    NASA Astrophysics Data System (ADS)

    Péré, J. C.; Colette, A.; Dubuisson, P.; Bessagnet, B.; Mallet, M.; Pont, V.

    2012-12-01

    Projections of aerosol emissions for 2030 have been recently generated and implemented in a comprehensive chemistry-transport model to analyse the future evolution of the aerosol radiative forcing over Europe. In this study, numerical developments based on an off-line coupling between the regional chemistry-transport model CHIMERE (extended by an aerosol optical module) and the radiative transfer code GAME have been implemented in order to simulate the interaction of physico-chemically resolved aerosols with radiation at regional scale. This novel approach is used to examine the shortwave aerosol direct radiative forcing response to two air pollution reduction scenarios for 2030 over Europe. Our study suggests that measures introduced to improve future air quality could have large implication on the aerosol climate forcing over Europe. Results of simulations indicate that abatement of aerosols in the near future could lead to a decrease of the aerosol cooling effect at the surface and at the top of the atmosphere over the main anthropogenic emission regions. Especially over the Moscow region, different strategies of reduction for scattering sulphate and absorbing black carbon aerosols between the two scenarios could result, however, in either a reduction or an enhancement in atmospheric radiative forcing.

  13. Mitigation of human-pathogenic fungi that exhibit resistance to medical agents: can clinical antifungal stewardship help?

    PubMed

    Hull, Claire M; Purdy, Nicola J; Moody, Suzy C

    2014-01-01

    Reducing indiscriminate antimicrobial usage to combat the expansion of multidrug-resistant human-pathogenic bacteria is fundamental to clinical antibiotic stewardship. In contrast to bacteria, fungal resistance traits are not understood to be propagated via mobile genetic elements, and it has been proposed that a global explosion of resistance to medical antifungals is therefore unlikely. Clinical antifungal stewardship has focused instead on reducing the drug toxicity and high costs associated with medical agents. Mitigating the problem of human-pathogenic fungi that exhibit resistance to antimicrobials is an emergent issue. This article addresses the extent to which clinical antifungal stewardship could influence the scale and epidemiology of resistance to medical antifungals both now and in the future. The importance of uncharted selection pressure exerted by agents outside the clinical setting (agricultural pesticides, industrial xenobiotics, biocides, pharmaceutical waste and others) on environmentally ubiquitous spore-forming molds that are lesserstudied but increasingly responsible for drug-refractory infections is considered.

  14. Defense Waste Processing Facility: Report of task force on options to mitigate the effect of nitrite on DWPF operations

    SciTech Connect

    Randall, D.; Marek, J.C.

    1992-03-01

    The possibility of accumulating ammonium nitrate (an explosive) as well as organic compounds in the DWPF Chemical Processing Cell Vent System was recently discovered. A task force was therefore organized to examine ways to avoid this potential hazard. Of thirty-two processing/engineering options screened, the task force recommended five options, deemed to have the highest technical certainty, for detailed development and evaluation: Radiolysis of nitrite in the tetraphenylborate precipitate slurry feed in a new corrosion-resistant facility. Construction of a Late Washing Facility for precipitate washing before transfer to the DWPF; Just-in-Time'' precipitation; Startup Workaround by radiolysis of nitrite in the existing corrosion-resistant Pump Pit tanks; Ammonia venting and organics separation in the DWPF; and, Estimated costs and schedules are included in this report.

  15. Embryo mechanics: balancing force production with elastic resistance during morphogenesis.

    PubMed

    Davidson, Lance A

    2011-01-01

    Morphogenesis requires the spatial and temporal control of embryo mechanics, including force production and mechanical resistance to those forces, to coordinate tissue deformation and large-scale movements. Thus, biomechanical processes play a key role in directly shaping the embryo. Additional roles for embryo mechanics during development may include the patterning of positional information and to provide feedback to ensure the success of morphogenetic movements in shaping the larval body and organs. To understand the multiple roles of mechanics during development requires familiarity with engineering principles of the mechanics of structures, the viscoelastic properties of biomaterials, and the integration of force and stress within embryonic structures as morphogenesis progresses. In this chapter, we review the basic engineering principles of biomechanics as they relate to morphogenesis, introduce methods for quantifying embryo mechanics and the limitations of these methods, and outline a formalism for investigating the role of embryo mechanics in birth defects. We encourage the nascent field of embryo mechanics to adopt standard engineering terms and test methods so that studies of diverse organisms can be compared and universal biomechanical principles can be revealed.

  16. Fluctuating Pressure Environments and Hydrodynamic Radial Force Mitigation for a Two Blade Unshrouded Inducer

    NASA Technical Reports Server (NTRS)

    Mulder, Andrew; Skelley, Stephen

    2011-01-01

    Fluctuating pressure data from water flow testing of an unshrouded two blade inducer revealed a cavitation induced oscillation with the potential to induce a radial load on the turbopump shaft in addition to other more traditionally analyzed radial loads. Subsequent water flow testing of the inducer with a rotating force measurement system confirmed that the cavitation induced oscillation did impart a radial load to the inducer. After quantifying the load in a baseline configuration, two inducer shroud treatments were selected and tested to reduce the cavitation induced load. The first treatment was to increase the tip clearance, and the second was to introduce a circumferential groove near the inducer leading edge. Increasing the clearance resulted in a small decrease in radial load along with some steady performance degradation. The groove greatly reduced the hydrodynamic load with little to no steady performance loss. The groove did however generate some new, relatively high frequency, spatially complex oscillations to the flow environment.

  17. Fluctuating Pressure Environments and Hydrodynamic Radial Force Mitigation for a Two Blade Unshrouded Inducer

    NASA Technical Reports Server (NTRS)

    Mulder, Andrew; Skelley, Stephen

    2011-01-01

    Fluctuating pressure data from water flow testing of an unshrouded two blade inducer revealed a cavitation induced oscillation with the potential to induce a radial load on the turbopump shaft in addition to other more traditionally analyzed radial loads. Subsequent water flow testing of the inducer with a rotating force measurement system confirmed that the cavitation induced oscillation did impart a radial load to the inducer. After quantifying the load in a baseline configuration, two inducer shroud treatments were selected and tested to reduce the cavitation induced load. The first treatment was to increase the tip clearance, and the second was to introduce a circumferential groove near the inducer leading edge. Increasing the clearance resulted in a small load decrease along with some steady performance degradation. The groove greatly reduced the hydrodynamic load with little to no steady performance loss. The groove did however generate some new, relatively high frequency, spatially complex oscillations to the environment.

  18. Does cryptic microbiota mitigate pine resistance to an invasive beetle-fungus complex? Implications for invasion potential

    PubMed Central

    Cheng, Chihang; Xu, Letian; Xu, Dandan; Lou, Qiaozhe; Lu, Min; Sun, Jianghua

    2016-01-01

    Microbial symbionts are known to assist exotic pests in their colonization of new host plants. However, there has been little evidence linking symbiotic invasion success to mechanisms for mitigation of native plant resistance. The red turpentine beetle (RTB) was introduced with a fungus, Leptographium procerum, to China from the United States and became a destructively invasive symbiotic complex in natural Pinus tabuliformis forests. Here, we report that three Chinese-resident fungi, newly acquired by RTB in China, induce high levels of a phenolic defensive chemical, naringenin, in pines. This invasive beetle-fungus complex is suppressed by elevated levels of naringenin. However, cryptic microbiotas in RTB galleries strongly degrade naringenin, and pinitol, the main soluble carbohydrate of P. tabuliformis, is retained in L. procerum-infected phloem and facilitate naringenin biodegradation by the microbiotas. These results demonstrate that cryptic microbiota mitigates native host plant phenolic resistance to an invasive symbiotic complex, suggesting a putative mechanism for reduced biotic resistance to symbiotic invasion. PMID:27621032

  19. The subsurface cross section resistivity using magnetotelluric method in Pelabuhan Ratu area, West Java, implication for geological hazard mitigation

    NASA Astrophysics Data System (ADS)

    Gaffar, Eddy Z.

    2016-02-01

    Pelabuhan Ratu area is located on the south coast of West Java. Pelabuhan Ratu area's rapid development and population growth were partly stimulated by the Indonesian Government Regulation No. 66 the year 1998 that made Pelabuhan Ratu the capital city of the district of Sukabumi. Because of this fact, it is very important to create a geological hazard mitigation plan for the area. Pelabuhan Ratu were passed by two major faults: Cimandiri fault in the western and Citarik fault in the eastern. Cimandiri fault starts from the upstream of Cimandiri River to the southern of Sukabumi and Cianjur city. While Citarik fault starts from the Citarik River until the Salak Mountain. These two faults needs to be observed closely as they are prone to cause earthquake in the area. To mitigate earthquake that is estimated will occur at Cimandiri fault or the Citarik fault, the Research Center for Geotechnology LIPI conducted research using Magnetotelluric (MT) method with artificial Phoenix MT tool to determine the cross-section resistivity of the Pelabuhan Ratu and the surrounding area. Measurements were taken at 40 points along the highway towards Jampang to Pelabuhan Ratu, and to Bandung towards Cibadak with a distance of less than 500 meters between the measuring points. Measurement results using this tool will generate AMT cross-section resistivity to a depth of 1500 meters below the surface. Cross-section resistivity measurement results showed that there was a layer of rock with about 10 Ohm-m to 1000 Ohm-m resistivity. Rocks with resistivity of 10 Ohm-m was interpreted as conductive rocks that were loose or sandstone containing water. If an earthquake to occur in this area, it will lead to a strong movement and liquefaction that will destroy buildings and potentially cause casualties in this area.

  20. Indirect costs of a nontarget pathogen mitigate the direct benefits of a virus-resistant transgene in wild Cucurbita

    PubMed Central

    Sasu, Miruna A.; Ferrari, Matthew J.; Du, Daolin; Winsor, James A.; Stephenson, Andrew G.

    2009-01-01

    Virus-resistant transgenic squash are grown throughout the United States and much of Mexico and it is likely that the virus-resistant transgene (VRT) has been introduced to wild populations repeatedly. The evolutionary fate of any resistance gene in wild populations and its environmental impacts depend upon trade-offs between the costs and benefits of the resistance gene. In a 3-year field study using a wild gourd and transgenic and nontransgenic introgressives, we measured the effects of the transgene on fitness, on herbivory by cucumber beetles, on the incidence of mosaic viruses, and on the incidence of bacterial wilt disease (a fatal disease vectored by cucumber beetles). In each year, the first incidence of zucchini yellow mosaic virus occurred in mid-July and spread rapidly through the susceptible plants. We found that the transgenic plants had greater reproduction through both male and female function than the susceptible plants, indicating that the VRT has a direct fitness benefit for wild gourds under the conditions of our study. Moreover, the VRT had no effect on resistance to cucumber beetles or the incidence of wilt disease before the spread of the virus. However, as the virus spread through the fields, the cucumber beetles became increasingly concentrated upon the healthy (mostly transgenic) plants, which increased exposure to and the incidence of wilt disease on the transgenic plants. This indirect cost of the VRT (mediated by a nontarget herbivore and pathogen) mitigated the overall beneficial effect of the VRT on fitness. PMID:19858473

  1. Mitigating the threat of artemisinin resistance in Africa: improvement of drug-resistance surveillance and response systems

    PubMed Central

    Talisuna, Ambrose O; Karema, Corine; Ogutu, Bernhards; Juma, Elizabeth; Logedi, John; Nyandigisi, Andrew; Mulenga, Modest; Mbacham, Wilfred F; Roper, Cally; Guerin, Philippe J; D’Alessandro, Umberto; Snow, Robert W

    2012-01-01

    Artemisinin-resistant Plasmodium falciparum malaria has emerged in western Cambodia and has been detected in western Thailand. The situation is ominously reminiscent of the emergence of resistance to chloroquine and to sulfadoxine–pyrimethamine several decades ago. Artemisinin resistance is a major threat to global public health, with the most severe potential effects in sub-Saharan Africa, where the disease burden is highest and systems for monitoring and containment of resistance are inadequate. The mechanisms that underlie artemisinin resistance are not fully understood. The main phenotypic trait associated with resistance is a substantial delay in parasite clearance, so far reported in southeast Asia but not in Africa. One of the pillars of the WHO global plan for artemisinin resistance containment is to increase monitoring and surveillance. In this Personal View, we propose strategies that should be adopted by malaria-endemic countries in Africa: resource mobilisation to reactivate regional surveillance networks, establishment of baseline parasite clearance profiles to serve as benchmarks to track emerging artemisinin resistance, improved data sharing to allow pooled analyses to identify rare events, modelling of risk factors for drug resistance, and development and validation of new approaches to monitor resistance. PMID:23099083

  2. IPM Use With the Deployment of a Non-High Dose Bt Pyramid and Mitigation of Resistance for Western Corn Rootworm (Diabrotica virgifera virgifera).

    PubMed

    Martinez, J C; Caprio, M A

    2016-03-27

    Recent detection of western corn rootworm resistance to Bt (Bacillus thuringiensis) corn prompted recommendations for the use of integrated pest management (IPM) with planting refuges to prolong the durability of Bt technologies. We conducted a simulation experiment exploring the effectiveness of various IPM tools at extending durability of pyramided Bt traits. Results indicate that some IPM practices have greater merits than others. Crop rotation was the most effective strategy, followed by increasing the non-Bt refuge size from 5 to 20%. Soil-applied insecticide use for Bt corn did not increase the durability compared with planting Bt with refuges alone, and both projected lower durabilities. When IPM participation with randomly selected management tools was increased at the time of Bt commercialization, durability of pyramided traits increased as well. When non-corn rootworm expressing corn was incorporated as an IPM option, the durability further increased.For corn rootworm, a local resistance phenomenon appeared immediately surrounding the resistant field (hotspot) and spread throughout the local neighborhood in six generations in absence of mitigation. Hotspot mitigation with random selection of strategies was ineffective at slowing resistance, unless crop rotation occurred immediately; regional mitigation was superior to random mitigation in the hotspot and reduced observed resistance allele frequencies in the neighborhood. As resistance alleles of mobile pests can escape hotspots, the scope of mitigation should extend beyond resistant sites. In the case of widespread resistance, regional mitigation was less effective at prolonging the life of the pyramid than IPM with Bt deployment at the time of commercialization.

  3. Early detection and mitigation of resistance to Bt maize by western corn rootworm (Coleoptera: Chrysomelidae)

    USDA-ARS?s Scientific Manuscript database

    Transgenic Bt maize that produces less than a high dose has been widely adopted and presents considerable insect resistance management (IRM) challenges. Western corn rootworm, Diabrotica virgifera virgifera LeConte, has rapidly evolved resistance to Bt maize in the field leading to local loss of eff...

  4. WIse-2005: Combined Aerobic and Resistive Exercise May Help Mitigate Bone Loss During 60-D Simulated Microgravity in Women

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.; Zwart, S. R.; Heer, M. A.; Lee, S. M. C.; Macias, B. R.; Schneider, S. M.; Trappe, S. M.; Hargens, A. R.

    2006-01-01

    Exercise can attenuate bone loss associated with disuse during bed rest (BR), an analog of space flight. Previous studies have examined the efficacy of aerobic or resistive exercise countermeasures, but not in combination. We sought to determine the effect of a combined resistive and aerobic exercise regimen on bone metabolism during BR. After a 20-d ambulatory adaptation to confinement and diet, 16 women participated in a 60-d head-down-tilt BR. Control subjects (CN, n=8) performed no countermeasures. Exercise subjects, (EX, n=8) participated in exercise alternating daily between supine treadmill exercise within lower body negative pressure and resistive fly-wheel exercise (6-d wk(sup -1)). In the last week of BR, bone resorption was greater (p less than 79 plus or minus 44%, mean plus or minus SD) and EX groups (64 50%). N-telopeptide also increased (CN: 51 plus or minus 34%; EX: 43 plus or minus 56%). However, bone-specific alkaline phosphatase, a bone formation marker, tended to be higher in EX (26 plus or minus 18%) than in CN (8 plus or minus 33%) groups. The combination of resistive and aerobic exercise does not prevent bone resorption, but may promote formation, potentially mitigating the net bone loss associated with simulated microgravity. This study was supported by CNES, CSA, ESA, NASA, and NASA grant NNJ04HF71G to ARH. MEDES (French Institute for Space Medicine and Physiology) organized the study.

  5. WIse-2005: Combined Aerobic and Resistive Exercise May Help Mitigate Bone Loss During 60-D Simulated Microgravity in Women

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.; Zwart, S. R.; Heer, M. A.; Lee, S. M. C.; Macias, B. R.; Schneider, S. M.; Trappe, S. M.; Hargens, A. R.

    2006-01-01

    Exercise can attenuate bone loss associated with disuse during bed rest (BR), an analog of space flight. Previous studies have examined the efficacy of aerobic or resistive exercise countermeasures, but not in combination. We sought to determine the effect of a combined resistive and aerobic exercise regimen on bone metabolism during BR. After a 20-d ambulatory adaptation to confinement and diet, 16 women participated in a 60-d head-down-tilt BR. Control subjects (CN, n=8) performed no countermeasures. Exercise subjects, (EX, n=8) participated in exercise alternating daily between supine treadmill exercise within lower body negative pressure and resistive fly-wheel exercise (6-d wk(sup -1)). In the last week of BR, bone resorption was greater (p less than 79 plus or minus 44%, mean plus or minus SD) and EX groups (64 50%). N-telopeptide also increased (CN: 51 plus or minus 34%; EX: 43 plus or minus 56%). However, bone-specific alkaline phosphatase, a bone formation marker, tended to be higher in EX (26 plus or minus 18%) than in CN (8 plus or minus 33%) groups. The combination of resistive and aerobic exercise does not prevent bone resorption, but may promote formation, potentially mitigating the net bone loss associated with simulated microgravity. This study was supported by CNES, CSA, ESA, NASA, and NASA grant NNJ04HF71G to ARH. MEDES (French Institute for Space Medicine and Physiology) organized the study.

  6. A strategy to provide long-term control of weedy rice while mitigating herbicide resistance transgene flow, and its potential use for other crops with related weeds.

    PubMed

    Gressel, Jonathan; Valverde, Bernal E

    2009-07-01

    Transgenic herbicide-resistant rice is needed to control weeds that have evolved herbicide resistance, as well as for the weedy (feral, red) rice problem, which has been exacerbated by shifting to direct seeding throughout the world-firstly in Europe and the Americas, and now in Asia, as well as in parts of Africa. Transplanting had been the major method of weedy rice control. Experience with imidazolinone-resistant rice shows that gene flow to weedy rice is rapid, negating the utility of the technology. Transgenic technologies are available that can contain herbicide resistance within the crop (cleistogamy, male sterility, targeting to chloroplast genome, etc.), but such technologies are leaky. Mitigation technologies tandemly couple (genetically link) the gene of choice (herbicide resistance) with mitigation genes that are neutral or good for the crop, but render hybrids with weedy rice and their offspring unfit to compete. Mitigation genes confer traits such as non-shattering, dwarfism, no secondary dormancy and herbicide sensitivity. It is proposed to use glyphosate and glufosinate resistances separately as genes of choice, and glufosinate, glyphosate and bentazone susceptibilities as mitigating genes, with a six-season rotation where each stage kills transgenic crop volunteers and transgenic crop x weed hybrids from the previous season.

  7. Resistance forces during boulder extraction from an asteroid

    NASA Astrophysics Data System (ADS)

    Kulchitsky, Anton V.; Johnson, Jerome B.; Reeves, David M.

    2016-10-01

    Planning for NASA's Asteroid Redirect Mission (ARM) requires estimating the forces that appear during extraction of a boulder from the surface of an asteroid with unknown surface regolith properties. These forces are estimated for a vertical constant force or acceleration pull and a rolling, constant force, torque (peel) on a 4-m diameter spherical boulder using both analytic and discrete element method (DEM) models considering the effects of microgravity and regolith cohesion using Johnson-Kendall-Roberts (JKR) model. Estimates of the bulk asteroid regolith cohesion strength derived from lunar and asteroid regolith studies ranged from 25 Pa to 250 Pa. JKR cohesive forces at particle contacts depend on particle surface energy and effective curvature radius (particle size). DEM particle size dependent cohesion parameters are linked to estimated regolith cohesion strength by simulating shear and tension tests over a range of DEM particle surface energies resulting in the formulation of the dependence of particle surface energy as a function of cohesion strength and particle size. Maximum extraction forces occur for a vertical pull through the boulder center of mass with constant acceleration. Extraction force decreases for a constant force pull to 0.62pc S where S is the boulder surface area embedded in the regolith and pc is the cohesion strength of the regolith. Boulder extraction by peeling produces the smallest forces by up to more than a factor of 2, as the failure across the boulder surface increases progressively rather than being fully engaged as occurs during a vertical pull extraction. Variations between DEM and analytic results differed from 9% to 17% over the range of regolith cohesion values and peel extraction leverage.

  8. Influence of Isoinertial-Pneumatic Mixed Resistances on Force-Velocity Relationship.

    PubMed

    Avrillon, Simon; Jidovtseff, Boris; Hug, François; Guilhem, Gaël

    2017-03-01

    Muscle strengthening is commonly based on the use of isoinertial loading, whereas variable resistances such as pneumatic loading may be implemented to optimize training stimulus. The purpose of the current study was to determine the effect of the ratio between pneumatic and isoinertial resistance on the force-velocity relationship during ballistic movements. A total of 15 participants performed 2 concentric repetitions of ballistic bench-press movements with intention to throw the bar at 30%, 45%, 60%, 75%, and 90% of the maximal concentric repetition with 5 resistance ratios including 100%, 75%, 50%, 25%, or 0% of pneumatic resistance, the additional load being isoinertial. Force-, velocity-, and power-time patterns were assessed and averaged over the concentric phase to determine the force-velocity and power-velocity relationships for each resistance ratio. Each 25% increase in the pneumatic part in the resistance ratio elicited higher movement velocity (+0.11 ± 0.03 m/s from 0% to 80% of the concentric phase) associated with lower force levels (-43.6 ± 15.2 N). Increased isoinertial part in the resistance ratio resulted in higher velocity toward the end of the movement (+0.23 ± 0.01 m/s from 90% to 100%). The findings show that the resistance ratio could be modulated to develop the acceleration phase and force toward the end of the concentric phase (pneumatic-oriented resistance). Inversely, isoinertial-oriented resistance should be used to develop maximal force and maximal power. Resistance modality could, therefore, be considered an innovative variable to modulate the training stimulus according to athletic purposes.

  9. Assessment of Structural Resistance of building 4862 to Earthquake and Tornado Forces [SEC 1 and 2

    SciTech Connect

    METCALF, I.L.

    1999-12-06

    This report presents the results of work done for Hanford Engineering Laboratory under contract Y213-544-12662. LATA performed an assessment of building 4862 resistance to earthquake and tornado forces.

  10. Current resistance sources and breeding strategies to mitigate Ug99 threat

    USDA-ARS?s Scientific Manuscript database

    Continued spread of race Ug99 (TTKSK) of Puccinia graminis from Eastern Africa to Yemen and Iran, and its evolution to overcome resistance genes Sr24 and Sr36 has further increased the genetic vulnerability of wheat crop in Africa, Middle East and Asia where about 90% of the area is sown to moderate...

  11. Warming by resistive heating maintains perioperative normothermia as well as forced air heating.

    PubMed

    Matsuzaki, Y; Matsukawa, T; Ohki, K; Yamamoto, Y; Nakamura, M; Oshibuchi, T

    2003-05-01

    Even mild perioperative hypothermia is associated with several severe adverse effects. Resistive heating has possible advantages compared with other active warming systems because it can heat several fields independently. To assess this new warming system, we measured core temperature in patients during surgery who were warmed with circulating water mattresses, forced air covers or resistive heating covers. Twenty-four patients undergoing laparoscopic cholecystectomy were randomly assigned to (i) circulating water mattress (38 degrees C), (ii) forced air warming (set to 'medium') or (iii) carbon-fibre resistive warming (38 degrees C). Warming was applied throughout anaesthesia and surgery. The groups were compared using one-way ANOVA and Student-Newman-Keuls tests. Confounding factors were similar among the groups. Core temperatures in each group decreased for 20 min, but subsequently increased in the forced air and resistive heating groups. There was no significant difference between the forced air and resistive heating groups at any time. In contrast, core temperature in the circulating water group continued to decrease. Consequently, core temperature in the circulating water group was significantly lower than in the other groups 30 min after anaesthetic induction and at later times. Resistive heating maintains core body temperature as well as forced air heating and both are better than circulating water. Resistive heating offers the advantage of adjustable heating pods.

  12. The occurrence of anomalous resistance and longitudinal electric fields on auroral lines of force

    NASA Astrophysics Data System (ADS)

    Kropotkin, A. P.

    1981-06-01

    A model for calculating the longitudinal current velocity of electrons on high latitude lines of force is proposed. These velocities may surpass the ion cyclotron current instability threshold in certain tubes of force while remaining below this threshold in others in close proximity. The turbulence arising as a result of this instability produces anomalous longitudinal resistance. The longitudinal current density is approximately proportional to the full longitudinal potential difference on a given line of force.

  13. Muramyl Dipeptide-Based Postbiotics Mitigate Obesity-Induced Insulin Resistance via IRF4.

    PubMed

    Cavallari, Joseph F; Fullerton, Morgan D; Duggan, Brittany M; Foley, Kevin P; Denou, Emmanuel; Smith, Brennan K; Desjardins, Eric M; Henriksbo, Brandyn D; Kim, Kalvin J; Tuinema, Brian R; Stearns, Jennifer C; Prescott, David; Rosenstiel, Philip; Coombes, Brian K; Steinberg, Gregory R; Schertzer, Jonathan D

    2017-05-02

    Intestinal dysbiosis contributes to obesity and insulin resistance, but intervening with antibiotics, prebiotics, or probiotics can be limited by specificity or sustained changes in microbial composition. Postbiotics include bacterial components such as lipopolysaccharides, which have been shown to promote insulin resistance during metabolic endotoxemia. We found that bacterial cell wall-derived muramyl dipeptide (MDP) is an insulin-sensitizing postbiotic that requires NOD2. Injecting MDP lowered adipose inflammation and reduced glucose intolerance in obese mice without causing weight loss or altering the composition of the microbiome. MDP reduced hepatic insulin resistance during obesity and low-level endotoxemia. NOD1-activating muropeptides worsened glucose tolerance. IRF4 distinguished opposing glycemic responses to different types of peptidoglycan and was required for MDP/NOD2-induced insulin sensitization and lower metabolic tissue inflammation during obesity and endotoxemia. IRF4 was dispensable for exacerbated glucose intolerance via NOD1. Mifamurtide, an MDP-based drug with orphan drug status, was an insulin sensitizer at clinically relevant doses in obese mice. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Viscous forces are predominant in the zona pellucida mechanical resistance

    NASA Astrophysics Data System (ADS)

    Papi, Massimiliano; Maiorana, Alessandro; Douet, Cécile; Maulucci, Giuseppe; Parasassi, Tiziana; Brunelli, Roberto; Goudet, Ghylène; De Spirito, Marco

    2013-01-01

    The zona pellucida (ZP) is a multilayer glycoprotein spherical shell surrounding mammalian eggs. The ZP's mechanical response plays a crucial role in mammalian fertilization and is a parameter commonly adopted in "in vitro fertilization" to characterize the oocytes quality. While it is assumed that ZP mechanical response is purely elastic, here we prove that dissipative forces cannot be neglected. Physiologically, this evidence implies that an increase in the spermatozoa motility can induce dramatic changes on the ZP reaction force turning ZP shell in an impenetrable barrier leading to fertility impairments.

  15. Bone loss during partial weight bearing (1/6th gravity) is mitigated by resistance and aerobic exercise in mice

    NASA Astrophysics Data System (ADS)

    Boudreaux, R. D.; Metzger, C. E.; Macias, B. R.; Shirazi-Fard, Y.; Hogan, H. A.; Bloomfield, S. A.

    2014-06-01

    Astronauts on long duration missions continue to experience bone loss, as much as 1-2% each month, for up to 4.5 years after a mission. Mechanical loading of bone with exercise has been shown to increase bone formation, mass, and geometry. The aim of this study was to compare the efficacy of two exercise protocols during a period of reduced gravitational loading (1/6th body weight) in mice. Since muscle contractions via resistance exercise impart the largest physiological loads on the skeleton, we hypothesized that resistance training (via vertical tower climbing) would better protect against the deleterious musculoskeletal effects of reduced gravitational weight bearing when compared to endurance exercise (treadmill running). Young adult female BALB/cBYJ mice were randomly assigned to three groups: 1/6 g (G/6; n=6), 1/6 g with treadmill running (G/6+RUN; n=8), or 1/6 g with vertical tower climbing (G/6+CLB; n=9). Exercise was performed five times per week. Reduced weight bearing for 21 days was achieved through a novel harness suspension system. Treadmill velocity (12-20 m/min) and daily run time duration (32-51 min) increased incrementally throughout the study. Bone geometry and volumetric bone mineral density (vBMD) at proximal metaphysis and mid-diaphysis tibia were assessed by in vivo peripheral quantitative computed tomography (pQCT) on days 0 and 21 and standard dynamic histomorphometry was performed on undemineralized sections of the mid-diaphysis after tissue harvest. G/6 caused a significant decrease (P<0.001) in proximal tibia metaphysis total vBMD (-9.6%). These reductions of tibia metaphyseal vBMD in G/6 mice were mitigated in both G/6+RUN and G/6+CLB groups (P<0.05). After 21 days of G/6, we saw an absolute increase in tibia mid-diaphysis vBMD and in distal metaphysis femur vBMD in both G/6+RUN and G/6+CLB mice (P<0.05). Substantial increases in endocortical and periosteal mineralizing surface (MS/BS) at mid-diaphysis tibia in G/6+CLB demonstrate that

  16. The tumor microenvironment is a dominant force in multidrug resistance

    PubMed Central

    Correia, Ana Luísa; Bissell, Mina J.

    2013-01-01

    The emergence of clinical drug resistance is still one of the most challenging factors in cancer treatment effectiveness. Until more recently, the assumption has been that random genetic lesions are sufficient to explain the progression of malignancy and escape from chemotherapy. Here we propose an additional perspective, one in which the tumor cells despite the malignant genome could find a microenvironment either within the tumor or as a dormant cell to remain polar and blend into an organized context. Targeting this dynamic interplay could be considered a new avenue to prevent therapeutic resistance, and may even provide a promising effective cancer treatment. PMID:22335920

  17. Experimental comparison of forces resisting viral DNA packaging and driving DNA ejection

    NASA Astrophysics Data System (ADS)

    Keller, Nicholas; Berndsen, Zachary T.; Jardine, Paul J.; Smith, Douglas E.

    2017-05-01

    We compare forces resisting DNA packaging and forces driving DNA ejection in bacteriophage phi29 with theoretical predictions. Ejection of DNA from prohead-motor complexes is triggered by heating complexes after in vitro packaging and force is inferred from the suppression of ejection by applied osmotic pressure. Ejection force from 0 % to 80 % filling is found to be in quantitative agreement with predictions of a continuum mechanics model that assumes a repulsive DNA-DNA interaction potential based on DNA condensation studies and predicts an inverse-spool conformation. Force resisting DNA packaging from ˜80 % to 100 % filling inferred from optical tweezers studies is also consistent with the predictions of this model. The striking agreement with these two different measurements suggests that the overall energetics of DNA packaging is well described by the model. However, since electron microscopy studies of phi29 do not reveal a spool conformation, our findings suggest that the spool model overestimates the role of bending rigidity and underestimates the role of intrastrand repulsion. Below ˜80 % filling the inferred forces resisting packaging are unexpectedly lower than the inferred ejection forces, suggesting that in this filling range the forces are less accurately determined or strongly temperature dependent.

  18. Implementation of National Space Policy on US Air Force End of Life Operations and Orbital Debris Mitigation

    DTIC Science & Technology

    2012-06-01

    the orbital debris problem in Low Earth Orbit (LEO). Therefore current EOL plans are written largely with the aim of reducing long-lasting debris that...Space Command policies for mitigation of orbital debris , this paper details several considerations for writing operational EOL plans, with special...assess and minimize orbital debris released during and after EOL satellite passivation by accidental explosions, by intentional breakup and due to on

  19. Force-Velocity, Impulse-Momentum Relationships: Implications for Efficacy of Purposefully Slow Resistance Training

    PubMed Central

    Schilling, Brian K.; Falvo, Michael J.; Chiu, Loren Z.F.

    2008-01-01

    The purpose of this brief review is to explain the mechanical relationship between impulse and momentum when resistance exercise is performed in a purposefully slow manner (PS). PS is recognized by ~10s concentric and ~4-10s eccentric actions. While several papers have reviewed the effects of PS, none has yet explained such resistance training in the context of the impulse-momentum relationship. A case study of normal versus PS back squats was also performed. An 85kg man performed both normal speed (3 sec eccentric action and maximal acceleration concentric action) and PS back squats over a several loads. Normal speed back squats produced both greater peak and mean propulsive forces than PS action when measured across all loads. However, TUT was greatly increased in the PS condition, with values fourfold greater than maximal acceleration repetitions. The data and explanation herein point to superior forces produced by the neuromuscular system via traditional speed training indicating a superior modality for inducing neuromuscular adaptation. Key pointsAs velocity approaches zero, propulsive force approaches zero, therefore slow moving objects only require force approximately equal to the weight of the resistance.As mass is constant during resistance training, a greater impulse will result in a greater velocity.The inferior propulsive forces accompanying purposefully slow training suggest other methods of resistance training have a greater potential for adaptation. PMID:24149464

  20. Comparison of resistive heating and forced-air warming to prevent inadvertent perioperative hypothermia.

    PubMed

    John, M; Crook, D; Dasari, K; Eljelani, F; El-Haboby, A; Harper, C M

    2016-02-01

    Forced-air warming is a commonly used warming modality, which has been shown to reduce the incidence of inadvertent perioperative hypothermia (<36°C). The reusable resistive heating mattresses offer a potentially cheaper alternative, however, and one of the research recommendations from the National Institute for Health and Care Excellence was to evaluate such devices formally. We conducted a randomized single-blinded study comparing perioperative hypothermia in patients receiving resistive heating or forced-air warming. A total of 160 patients undergoing non-emergency surgery were recruited and randomly allocated to receive either forced-air warming (n=78) or resistive heating (n=82) in the perioperative period. Patient core temperatures were monitored after induction of anaesthesia until the end of surgery and in the recovery room. Our primary outcome measures included the final intraoperative temperature and incidence of hypothermia at the end of surgery. There was a significantly higher rate of hypothermia at the end of surgery in the resistive heating group compared with the forced-air warming group (P=0.017). Final intraoperative temperatures were also significantly lower in the resistive heating group (35.9 compared with 36.1°C, P=0.029). Hypothermia at the end of surgery in both warming groups was common (36% forced air warming, 54% resistive heating). Our results suggest that forced-air warming is more effective than resistive heating in preventing postoperative hypothermia. NCT01056991. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Effect of rolling resistance on poling forces and metabolic demands of roller skiing.

    PubMed

    Millet, G Y; Hoffman, M D; Candau, R B; Buckwalter, J B; Clifford, P S

    1998-05-01

    To examine the effect of an increase in roller ski rolling resistance on the physiological and upper body demands of roller skiing with the V2-alternate technique. Nine highly skilled cross-country skiers roller skied at three paced speeds on a flat oval loop using roller skis with high (HiR) and low (LowR) rolling resistance. Oxygen uptake (VO2), heart rate, and poling forces were measured during the last 30 s and rating of perceived exertion (RPE) was requested immediately after each 4-min bout of roller skiing. VO2 and all force-related variables increased significantly with speed and were higher (P < 0.01) for HiR at given speeds. Poling time was similar between HiR and LowR, whereas poling recovery time was shorter (P = 0.0002) and cycle rate was higher (P = 0.002) for HiR. For given VO2 levels, peak and average forces, heart rates, and RPE values were similar between HiR and LowR, whereas average poling force across the cycle was greater (P = 0.006) and duty cycle (i.e., percentage of cycle when poling forces were applied) was higher (P = 0.0001) with HiR. 1) The decrease in poling recovery time and increase in cycle rate associated with an increase in roller ski rolling resistance is comparable to the effect previously observed from increasing grade and probably occurs as a means of limiting deceleration. 2) Since changes in rolling resistance do not alter the relationships of RPE and heart rate with VO2, the central cardiovascular adaptations from roller ski training should not be affected by the rolling resistance of the roller skis. 3) Higher resistance roller skis are likely to induce greater upper body aerobic adaptations than lower resistance roller skis.

  2. Air Force is Developing Risk-Mitigation Strategies to Manage Potential Loss of the RD-180 Engine (REDACTED)

    DTIC Science & Technology

    2015-03-05

    launched on its rocket- estimated completion date of May 2015. Air Force will require verification that SpaceX can meet payload integration...design and accelerate integration capability at Space Exploration Technologies Corporation ( SpaceX )1 launch sites. o The Air Force does not intend to...accelerate integration capabilities at SpaceX launch sites because of the studies it directed, but will require verification that SpaceX can meet

  3. Narcissistic Force Meets Systemic Resistance: The Energy Clash Model.

    PubMed

    Sedikides, Constantine; Campbell, W Keith

    2017-05-01

    This article focuses on the interplay between narcissistic leaders and organizations. It attempts to capture the gist of this interplay with a model outlining the narcissistic organizational trajectory. The Energy Clash Model borrows and adapts a phase/state physics metaphor to conceptualize narcissism as a force that enters or emerges in a stable system (i.e., organization) as a leader, destabilizes it, and stabilizes it at a different state or is expelled. The model consists of three time-contingent phases: perturbation, conflict, and resolution. Narcissists create instability through waves of excitement, proposed reforms, and an inspiring vision for organization's future ( perturbation). With the passage of time, though, systemic awareness and alertness intensify, as organizational costs-in terms of human resources and monetary losses-accrue. Narcissistic energy clashes directly with the organization ( conflict), a clash likely to restabilize the system eventually. The conflict may provoke the exit of the narcissistic leader or his or her accommodation, that is, steps or controls negotiated between the system and the leader ( resolution). Although narcissism is subject to organizational liability, narcissistic energy, when managed and directed properly, may contribute to organizational innovation and evolution. Thus, several interventions for working with narcissistic leaders are discussed.

  4. Ground reaction force comparison of controlled resistance methods to isoinertial loading of the squat exercise - biomed 2010.

    PubMed

    Paulus, David C; Reynolds, Michael C; Schilling, Brian K

    2010-01-01

    The ground reaction force during the concentric (raising) portion of the squat exercise was compared to that of isoinertial loading (free weights) for three pneumatically controlled resistance methods: constant resistance, cam force profile, and proportional force control based on velocity. Constant force control showed lower ground reaction forces than isoinertial loading throughout the range of motion (ROM). The cam force profile exhibited slightly greater ground reaction forces than isoinertial loading at 10 and 40% ROM with fifty-percent greater loading at 70% ROM. The proportional force control consistently elicited greater ground reaction force than isoinertial loading, which progressively ranged from twenty to forty percent increase over isoinertial loading except for being approximately equal at 85% ROM. Based on these preliminary results, the proportional control shows the most promise for providing loading that is comparable in magnitude to isoinertial loading. This technology could optimize resistance exercise for sport-specific training or as a countermeasure to atrophy during spaceflight.

  5. Jammed granular cones affect frictional resistive forces at the onset of intrusion

    NASA Astrophysics Data System (ADS)

    Aguilar, Jeffrey; Goldman, Daniel

    Characterizing the functional form of granular resistive forces has allowed for analysis of the locomotion of animals and robots on and within dry granular media. Resistive force theory (RFT) has been an effective tool in predicting these forces for various locomotive gaits within the ``frictional fluid'' regime, where intrusions are sufficiently slow such that granular inertial effects are negligible. These forces have been typically described by a linear dependence to submersion depth. However, recent experiments on robotic jumping [Aguilar & Goldman, Nature Physics, 2015] have revealed the importance of considering the nonlinear effects at the onset of intrusion to accurately predict robot kinematics. Particle image velocimetry (PIV) analysis of sidewall grain flow during foot intrusion reveals a jammed granular cone that develops beneath the foot at the onset of intrusion. A geometric model of cone development combined with empirical RFT forces on angled conical surfaces was able to predict the non-linear force trajectory vs. depth for experimental intrusions of various foot sizes, suggesting that intruders experience non-linear frictional forces according to the shape of the granular jamming fronts that form at the onset of movement. This work was supported by NSF Physics of Living Systems, Burroughs Wellcome Fund, and the Army Research Office.

  6. Foot-Ground Reaction Force During Resistance Exercise in Parabolic Flight

    NASA Technical Reports Server (NTRS)

    Lee, Stuart M. C.; Cobb, Kendall; Loehr, James A.; Nguyen, Daniel; Schneider, Suzanne M.

    2003-01-01

    An interim Resistance Exercise Device (iRED) was designed to provide resistive exercise as a countermeasure to space flight-induced loss of muscle strength and endurance as well as decreased bone mineral density. The purpose of this project was to compare foot-ground reaction force during iRED exercise in normal gravity (l-g) versus micro gravity (O-g) achieved during parabolic flight. METHODS: Four subjects performed three exercises using the iRED (squat, heel raise, and deadlift) during I-g and O-g at a moderate intensity (60% of maximum strength during deadlift exercise). Foot-ground reaction force was measured in three axes (x,y,z) using a force plate, and the magnitude of the resultant force vector was calculated (r = X 2 + y2 + Z2 ). Range of motion (ROM) was measured using a linear encoder. Peak force (PkF) and total work (TW) were calculated using a customized computer program. Paired t-tests were used to test if significant differences (p.::::0.05) were observed between I-g and O-g exercise. RESULTS: PkF and TW measured in the resultant axis were significantly less in O-g for each of the exercises tested. During O-g, PkF was 42-46% and TW was 33- 37% of that measured during I-g. ROM and average time to complete each repetition were not different from I-g to O-g. CONCLUSIONS: When performing exercises in which body mass is a portion of the resistance during I-g, PkF and TW measured during resistive exercise were reduced approximately 60-70% during O-g. Thus, a resistive exercise device during O-g will be required to provided higher resistances to induce a similar training stimulus to that on Earth.

  7. Multimode resistive switching in nanoscale hafnium oxide stack as studied by atomic force microscopy

    SciTech Connect

    Hou, Y. E-mail: lfliu@pku.edu.cn; Celano, U.; Vandervorst, W.; Goux, L.; Degraeve, R.; Jurczak, M.; Liu, L. E-mail: lfliu@pku.edu.cn; Cheng, Y.; Kang, J.

    2016-07-11

    The nanoscale resistive switching in hafnium oxide stack is investigated by the conductive atomic force microscopy (C-AFM). The initial oxide stack is insulating and electrical stress from the C-AFM tip induces nanometric conductive filaments. Multimode resistive switching can be observed in consecutive operation cycles at one spot. The different modes are interpreted in the framework of a low defect quantum point contact theory. The model implies that the optimization of the conductive filament active region is crucial for the future application of nanoscale resistive switching devices.

  8. Silicone oil contamination and electrical contact resistance degradation of low-force gold contacts.

    SciTech Connect

    Dugger, Michael Thomas; Dickrell, Daniel John, III

    2006-02-01

    Hot-switched low-force gold electrical contact testing was performed using a nanomechanical test apparatus to ascertain the sensitivity of simulated microelectromechanical systems (MEMS) contact to silicone oil contamination. The observed cyclic contact resistance degradation was dependent on both closure rate and noncontact applied voltage. The decomposition of silicone oil from electrical arcing was hypothesized as the degradation mechanism.

  9. Early and late rate of force development: differential adaptive responses to resistance training?

    PubMed

    Andersen, L L; Andersen, J L; Zebis, M K; Aagaard, P

    2010-02-01

    The objective of this study is to investigate the potentially opposing influence of qualitative and quantitative muscular adaptations in response to high-intensity resistance training on contractile rate of force development (RFD) in the early (<100 ms) and later phases (>200 ms) of rising muscle force. Fifteen healthy young males participated in a 14-week resistance training intervention for the lower body and 10 matched subjects participated as controls. Maximal muscle strength (MVC) and RFD were measured during maximal voluntary isometric contraction of the quadriceps femoris muscle. Muscle biopsies were obtained from the vastus lateralis. The main findings were that RFD in the late phase of rising muscle force increased in response to resistance training whereas early RFD remained unchanged and early relative RFD (i.e., RFD/MVC) decreased. Quantitatively, muscle fiber cross-sectional area and MVC increased whereas, qualitatively, the relative proportion of type IIX muscle fibers decreased. Multiple regression analysis showed that while increased MVC positively influenced both early and late RFD, decreased-type IIX negatively influenced early RFD only. In conclusion, early and late RFD responded differently to high-intensity resistance training due to differential influences of qualitative and quantitative muscular adaptations on early and later phases of rising muscle force.

  10. Defense Waste Processing Facility: Report of task force on options to mitigate the effect of nitrite on DWPF operations. Savannah River Site 200-S Area

    SciTech Connect

    Randall, D.; Marek, J.C.

    1992-03-01

    The possibility of accumulating ammonium nitrate (an explosive) as well as organic compounds in the DWPF Chemical Processing Cell Vent System was recently discovered. A task force was therefore organized to examine ways to avoid this potential hazard. Of thirty-two processing/engineering options screened, the task force recommended five options, deemed to have the highest technical certainty, for detailed development and evaluation: Radiolysis of nitrite in the tetraphenylborate precipitate slurry feed in a new corrosion-resistant facility. Construction of a Late Washing Facility for precipitate washing before transfer to the DWPF; ``Just-in-Time`` precipitation; Startup Workaround by radiolysis of nitrite in the existing corrosion-resistant Pump Pit tanks; Ammonia venting and organics separation in the DWPF; and, Estimated costs and schedules are included in this report.

  11. Resistance to alveolar shape change limits range of force propagation in lung parenchyma.

    PubMed

    Ma, Baoshun; Smith, Bradford J; Bates, Jason H T

    2015-06-01

    We have recently shown that if the lung parenchyma is modeled in 2 dimensions as a network of springs arranged in a pattern of repeating hexagonal cells, the distortional forces around a contracting airway propagate much further from the airway wall than classic continuum theory predicts. In the present study we tested the hypothesis that this occurs because of the negligible shear modulus of a hexagonal spring network. We simulated the narrowing of an airway embedded in a hexagonal network of elastic alveolar walls when the hexagonal cells of the network offered some resistance to a change in shape. We found that as the forces resisting shape change approach about 10% of the forces resisting length change of an individual spring the range of distortional force propagation in the spring network fell of rapidly as in an elastic continuum. We repeated these investigations in a 3-dimensional spring network composed of space-filling polyhedral cells and found similar results. This suggests that force propagation away from a point of local parenchymal distortion also falls off rapidly in real lung tissue.

  12. RESISTANCE TO ALVEOLAR SHAPE CHANGE LIMITS RANGE OF FORCE PROPAGATION IN LUNG PARENCHYMA

    PubMed Central

    Ma, Baoshun; Smith, Bradford J.; Bates, Jason H.T.

    2015-01-01

    We have recently shown that if the lung parenchyma is modeled in 2 dimensions as a network of springs arranged in a pattern of repeating hexagonal cells, the distortional forces around a contracting airway propagate much further from the airway wall than classic continuum theory predicts. In the present study we tested the hypothesis that this occurs because of the negligible shear modulus of a hexagonal spring network. We simulated the narrowing of an airway embedded in a hexagonal network of elastic alveolar walls when the hexagonal cells of the network offered some resistance to a change in shape. We found that as the forces resisting shape change approach about 10% of the forces resisting length change of an individual spring the range of distortional force propagation in the spring network fell of rapidly as in an elastic continuum. We repeated these investigations in a 3-dimensional spring network composed of space-filling polyhedral cells and found similar results. This suggests that force propagation away from a point of local parenchymal distortion also falls off rapidly in real lung tissue. PMID:25812796

  13. Effect of simulated resistance, fleeing, and use of force on standardized field sobriety testing.

    PubMed

    Ho, Jeffrey; Dawes, Donald; Nystrom, Paul; Moore, Johanna; Steinberg, Lila; Tilton, Annemarie; Miner, James

    2015-07-01

    When a law enforcement officer (LEO) stops a suspect believed to be operating (a vehicle) while impaired (OWI), the suspect may resist or flee, and the LEO may respond with force. The suspect may then undergo a Standardized Field Sobriety Test (SFST) to gauge impairment. It is not known whether resistance, fleeing, or actions of force can create an inaccurate SFST result. We examined the effect of resistance, fleeing, and force on the SFST. Human volunteers were prospectively randomized to have a SFST before and after one of five scenarios: (1) five-second conducted electrical weapon exposure; (2) 100-yard (91.4 m) sprint; (3) 45-second physical fight; (4) police dog bite with protective gear; and (5) Oleoresin Capsicum spray to the face with eyes shielded. The SFST was administered and graded by a qualified LEO. After the SFST, the volunteer entered their scenario and was then administered another SFST. Data were analyzed using descriptive statistics. SFST performance was compared before and after using chi-square tests. Fifty-seven subjects enrolled. Three received a single-point penalty during one component of the three-component SFST pre-scenario. No subject received a penalty point in any components of the SFST post-scenario (p = 0.08). This is the first human study to examine the effects of physical resistance, flight, and use of force on the SFST result. We did not detect a difference in the performance of subjects taking the SFST before and after exposure to resistance, flight, or a simulated use of force. © Australian Council for Educational Research 2014.

  14. Foot-ground reaction force during resistive exercise in parabolic flight

    NASA Technical Reports Server (NTRS)

    Lee, Stuart M C.; Cobb, Kendall; Loehr, James A.; Nguyen, Daniel; Schneider, Suzanne M.

    2004-01-01

    INTRODUCTION: An interim resistance exercise device (iRED) was designed to provide resistive exercise as a countermeasure to spaceflight-induced loss of muscle strength and endurance as well as decreased bone mineral density. The purpose of this project was to compare foot-ground reaction force during iRED exercise in normal gravity (1 G) vs. microgravity (0 G) achieved during parabolic flight. METHODS: There were four subjects who performed three exercises (squat, heel raise, and deadlift) using the iRED during 1 G and 0 G at a moderate intensity (60% of maximum strength during deadlift exercise). Foot-ground reaction force was measured in the three orthogonal axes (x, y, z) using a force plate, and the magnitude of the resultant force vector was calculated (r = square root(x2 + y2 + z2)). Linear displacement (LD) was measured using a linear transducer. Peak force (Fpeak) and an index of total work (TWi) were calculated using a customized computer program. Paired t-tests were used to test if significant differences (p < or = 0.05) were observed between 1 G and 0 G exercise. RESULTS: Fpeak and TWi measured in the resultant axis were significantly less in 0 G for each of the exercises tested. During 0 G, Fpeak was 42-46% and TWi was 33-37% of that measured during 1 G. LD and average time to complete each repetition were not different from 1 G to 0 G. CONCLUSIONS: Crewmembers who perform resistive exercises during spaceflight that include the movement of a large portion of their body mass will require much greater external resistive force during 0 G than 1 G exercise to provide a sufficient stimulus to maintain muscle and bone mass.

  15. Foot-ground reaction force during resistive exercise in parabolic flight

    NASA Technical Reports Server (NTRS)

    Lee, Stuart M C.; Cobb, Kendall; Loehr, James A.; Nguyen, Daniel; Schneider, Suzanne M.

    2004-01-01

    INTRODUCTION: An interim resistance exercise device (iRED) was designed to provide resistive exercise as a countermeasure to spaceflight-induced loss of muscle strength and endurance as well as decreased bone mineral density. The purpose of this project was to compare foot-ground reaction force during iRED exercise in normal gravity (1 G) vs. microgravity (0 G) achieved during parabolic flight. METHODS: There were four subjects who performed three exercises (squat, heel raise, and deadlift) using the iRED during 1 G and 0 G at a moderate intensity (60% of maximum strength during deadlift exercise). Foot-ground reaction force was measured in the three orthogonal axes (x, y, z) using a force plate, and the magnitude of the resultant force vector was calculated (r = square root(x2 + y2 + z2)). Linear displacement (LD) was measured using a linear transducer. Peak force (Fpeak) and an index of total work (TWi) were calculated using a customized computer program. Paired t-tests were used to test if significant differences (p < or = 0.05) were observed between 1 G and 0 G exercise. RESULTS: Fpeak and TWi measured in the resultant axis were significantly less in 0 G for each of the exercises tested. During 0 G, Fpeak was 42-46% and TWi was 33-37% of that measured during 1 G. LD and average time to complete each repetition were not different from 1 G to 0 G. CONCLUSIONS: Crewmembers who perform resistive exercises during spaceflight that include the movement of a large portion of their body mass will require much greater external resistive force during 0 G than 1 G exercise to provide a sufficient stimulus to maintain muscle and bone mass.

  16. To Click or Not to Click Technology and Human Factors to Mitigate Phishing Attacks on Air Force Networks

    DTIC Science & Technology

    2011-02-17

    incorporate visual elements or some form of pop - up warning to alert users to potentially risky web sites. Current Air Force anti-phishing efforts include all...examples of passive actions, and full interruptions or pop - ups that the user must click to dismiss are examples of active forms. Wu, et al. studied the...designers to create scam web pages, and rent access to compromised computers to lay the foundations for the phishing campaign. The phisher himself does not

  17. Shear strength and force transmission in granular media with rolling resistance.

    PubMed

    Estrada, Nicolas; Taboada, Alfredo; Radjaï, Farhang

    2008-08-01

    We investigate a class of granular materials characterized by the possibility of interlocking between the particles. The interlocking is modeled by its effect through rolling resistance depending on relative rotation and normal force at the contact points and involving a single parameter analogous to the sliding friction coefficient. The model, which is introduced in the framework of the contact dynamics method, is applied to simulate the simple shear of a large granular sample. We present a detailed analysis regarding the influence of rolling and sliding friction parameters on the macroscopic response in terms of shear strength, fabric properties, and force transmission. Interestingly, two distinct regimes can be distinguished in which the steady-state shear strength is controlled by either rolling resistance or sliding friction. The relative contributions of rolling and sliding contacts to the shear strength are consistent with the same two regimes. Interlocking strongly affects the force network by enhancing the arching effect and thus increasing the relative importance of weak contact forces and torques, which is reflected in a decreasing power-law probability distribution of the contact forces and torques below the mean. Due to the combined effect of friction and interlocking, the force-carrying backbone takes an increasingly columnar aspect involving a low fraction of particles. Our data suggest that the nature of the weak contact network is strongly affected by the formation of these columns of particles which do not need to be propped laterally. In particular, in the limit of high rolling resistance and sliding friction, the role of the weak network of contacts is no longer to prop the force chains, but, like the strong contact network, to actively sustain the deviatoric load imposed on the system.

  18. Force.

    ERIC Educational Resources Information Center

    Gamble, Reed

    1989-01-01

    Discusses pupil misconceptions concerning forces. Summarizes some of Assessment of Performance Unit's findings on meaning of (1) force, (2) force and motion in one dimension and two dimensions, and (3) Newton's second law. (YP)

  19. Force.

    ERIC Educational Resources Information Center

    Gamble, Reed

    1989-01-01

    Discusses pupil misconceptions concerning forces. Summarizes some of Assessment of Performance Unit's findings on meaning of (1) force, (2) force and motion in one dimension and two dimensions, and (3) Newton's second law. (YP)

  20. Resistance of single polyaniline fibers and their junctions measured by double-probe atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Higuchi, Rintaro; Shingaya, Yoshitaka; Nakayama, Tomonobu

    2016-08-01

    Electrical properties of polyaniline (PANI) fibers are of our interest as a component of network materials. Using a multiple-probe atomic force microscope with tuning fork probes, we investigated the resistance of single PANI fibers and their cross-point junction where the fibers contact each other. The resistivity of single PANI fibers was measured to be on the order of 10 Ω cm, and the contact resistance between PANI fibers was on the order of GΩ. The resistances through single cross-point junctions between two PANI fibers were very much dependent on the experimental condition, that is, the cross-point junction is stabilized or destabilized by physically placing the probes onto the two fibers. This suggests the nanomechanical instability of the cross-point junctions and a possibility to construct strain-responsive PANI fiber networks.

  1. Unravelling of a mechanism of resistance to colistin in Klebsiella pneumoniae using atomic force microscopy.

    PubMed

    Formosa, C; Herold, M; Vidaillac, C; Duval, R E; Dague, E

    2015-08-01

    In this study we focused on the mechanism of colistin resistance in Klebsiella pneumoniae. We used two strains of K. pneumoniae: a colistin-susceptible strain (K. pneumoniae ATCC 700603, KpATCC) and its colistin-resistant derivative (KpATCCm, MIC of colistin 16 mg/L). We performed a genotypic analysis based on the expression of genes involved in LPS synthesis and L-Ara4N moiety addition. We also explored the status of the mgrB gene. Then, a phenotypic analysis was performed using atomic force microscopy (AFM). The Young modulus was extracted from force curves fitted using the Hertz model, and stiffness values were extracted from force curves fitted using the Hooke model. We failed to observe any variation in the expression of genes implicated in LPS synthesis or L-Ara4N moiety addition in KpATCCm, in the absence of colistin or under colistin pressure (versus KpATCC). This led us to identify an insertional inactivation/mutation in the mgrB gene of KpATCCm. In addition, morphology results obtained by AFM showed that colistin removed the capsule from the susceptible strain, but not from the resistant strain. Nanomechanical data on the resistant strain showed that colistin increased the Young modulus of the capsule. Extend force curves recorded on top of the cells allowed us to make the following hypothesis about the nanoarchitecture of the capsule of the two strains: KpATCC has a soft capsule consisting of one layer, whereas the KpATCCm capsule is harder and organized in several layers. We hypothesize that capsular polysaccharides might be implicated in the mechanism of colistin resistance in K. pneumoniae, depending on its genotype. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  2. [Evaluation of thermal resistance of Azotobacter chroococcum 66 using atomic force microscopy].

    PubMed

    Oliunina, L N; Matskova, Iu A; Goncharova, T A; Gushchina, Iu Iu

    2009-01-01

    A possibility to use atomic force microscopy (AFM) for comparative analysis of thermal resistance of Azotobacter chroococcum 66 cells has been studied. The sizes of bacteria cells and the structuredness of the cytoderm have been shown to vary depending on the dose of hyperthermic action and on the composition of the media for heating and subsequent incubation. A thermally induced increase of a standard roughness parameter (R(a)) and of cell sizes has been revealed to reflect an increased level of their resistance to hyperthermia.

  3. Dielectric interpretation of Lei-Ting nonlinear force-momentum-balance transport equation for isothermal resistivity

    NASA Astrophysics Data System (ADS)

    Horing, N. J. M.; Lei, X. L.; Cui, H. L.

    1986-05-01

    A dielectric interpretation of the nonlinear Lei-Ting force-momentum-balance transport equation for steady-state dc current flow is developed here in correspondence with standard techniques for calculating fast-particle energy loss to a plasmalike medium. In conjunction with this we interpret the result to be an isothermal resistivity calculated to lowest order in the impurity scattering potentials, isothermal in the sense that all energy dissipated is removed from the system, essentially instantaneously as it is generated, by a heat bath in contact with the system which maintains it at constant temperature throughout the nonlinear dc conduction process. On the basis of its isothermal character, we argue that the Lei-Ting dc resistivity calculated to lowest order in the impurity scattering potentials-whose linear limit is significantly different from the corresponding linear resistivity of an adiabatic character (for a system admitting no drainoff of dissipated energy, developing under a purely mechanical Hamiltonian)-is immune to serious critical objections of the type brought by Argyres and Sigel against similar lowest-order adiabatic linear resistivity calculations some time ago. Moreover, we also show that a dielectric Lei-Ting type formulation of linearized ac resistivity leads to the standard high-frequency linear resistivity formula, and that its zero-frequency limit naturally yields the isothermal dc linear Lei-Ting resistivity.

  4. Supercoiled Minivector DNA resists shear forces associated with gene therapy delivery

    PubMed Central

    Catanese, D J; Fogg, J M; Schrock, D E; Gilbert, B E; Zechiedrich, L

    2012-01-01

    Supercoiled DNAs varying from 281 to 5302 bp were subjected to shear forces generated by aerosolization or sonication. DNA shearing strongly correlated with length. Typical sized plasmids (⩾3000 bp) degraded rapidly. DNAs 2000–3000 bp persisted ∼10 min. Even in the absence of condensing agents, supercoiled DNA <1200 bp survived nebulization, and increased forces of sonication were necessary to shear it. Circular vectors were considerably more resistant to shearing than linear vectors of the same length. DNA supercoiling afforded additional protection. These results show the potential of shear-resistant Minivector DNAs to overcome one of the major challenges associated with gene therapy delivery. PMID:21633394

  5. Measurement of elastic resisting forces of intraocular haptic loops of varying geometrical designs and material composition.

    PubMed

    Guthoff, R; Abramo, F; Draeger, J; Chumbley, L

    1990-09-01

    The relationship between experimentally induced intraocular lens (IOL) haptic deformation and resulting elastic haptic counter-resisting forces measured by electronic dynamometry was examined for 34 different IOL haptics of varying material composition and geometrical designs. Poly(methyl methacrylate) (PMMA) and polypropylene loops of similar geometry did not fundamentally differ from one another, although lenses of differing geometry behaved differently. Unlike PMMA and polypropylene loops, soft haptics of poly-HEMA and silicone rubber demonstrated a larger elastic resistance force to the same degree of deformation. This was based upon design characteristics of the lenses and not upon intrinsic properties of the materials, which would have produced the opposite result. By comparative analysis of these dynamometer measurements and considerations of the lens design and elastic properties (including memory) of the component materials, we can calculate the stresses upon the zonular and capsular bag structures during and after IOL implantation.

  6. A biomechanical review of the techniques used to estimate or measure resistive forces in swimming.

    PubMed

    Sacilotto, Gina B D; Ball, Nick; Mason, Bruce R

    2014-02-01

    Resistive or drag forces encountered during free swimming greatly influence the swim performance of elite competitive swimmers. The benefits in understanding the factors which affect the drag encountered will enhance performance within the sport. However, the current techniques used to experimentally measure or estimate drag values are questioned for their consistency, therefore limiting investigations in these factors. This paper aims to further understand how the resistive forces in swimming are measured and calculated. All techniques outlined demonstrate both strengths and weaknesses in the overall assessment of free swimming. By reviewing all techniques in this area, the reader should be able to select which one is best depending on what researchers want to gain from the testing.

  7. Enhanced H-reflex with resistance training is related to increased rate of force development.

    PubMed

    Holtermann, Andreas; Roeleveld, Karin; Engstrøm, Morten; Sand, Trond

    2007-10-01

    Parallel increases in strength and rate of force development (RFD) are well-known outcomes from the initial phase of resistance training. However, it is unknown whether neural adaptations with training contribute to improvements of both factors. The aim of this study was to examine whether changes in H-reflex amplitude with resistance training can explain the gain in strength or rather be associated with RFD. Twelve subjects carried out 3 weeks of isometric maximal plantarflexion training, whereas 12 subjects functioned as controls. H-reflexes were elicited in the soleus muscle during rest and sub-maximal contractions at 20 and 60% of maximal voluntary contraction (MVC). In addition, surface electromyography (sEMG) was recorded from the soleus, gastrocnemius and tibialis anterior muscles during MVC. The resistance training provided increases in maximal force of 18%, RFD of 28% and H-reflex amplitude during voluntary contractions of 17 and 15% while no changes occurred in the control group. In contrast, the maximal M-wave, the maximal H-reflex to maximal M-wave ratio during rest and sEMG during MVC did not change with training. There was a positive correlation between percentage changes in H-reflex amplitude and RFD with training (r = 0.59), while significant association between percentage changes in H-reflex amplitude and maximal force was not found. These findings indicate the occurrence of changed motoneuron excitability or presynaptic inhibition during the initial phase of resistance training. This is the first study to document that increased RFD with resistance training is associated with changes in reflex excitability.

  8. Force and power characteristics of a resistive exercise device for use in space

    NASA Astrophysics Data System (ADS)

    Berg, Hans E.; Tesch, Per A.

    We have developed a non-gravity dependent mechanical device, which provides resistance during coupled concentric and eccentric muscle actions, through the inertia of a spinning fly-wheel (Fly-Wheel Ergometry; FWE). Our research shows that lower-limb FWE exercise can produce forces and thus muscular stress comparable to what is typical of advanced resistance training using free weights. FWE also offers greater training stimuli during eccentric relative to concentric muscle actions, as evidenced by force and electromyographic (EMG) measurements. Muscle use of specific muscle groups, as assessed by the exercise-induced contrast shift of magnetic resonance images, is similar during lower-limb FWE and the barbell squat. Unlike free-weight exercise, FWE allows for maximal voluntary effort in each repetition of an exercise bout. Likewise, FWE exercise, not unassisted free-weight exercise, produces eccentric "overload". Collectively, the inherent features of this resistive exercise device and the results of the physiological evaluations we have performed, suggest that resistance exercise using FWE could be used as an effective exercise counter-measure in space. The flywheel principle can be employed to any exercise configuration and designed into a compact device allowing for exercises stressing those muscles and bone structures, which are thought to be most affected by long-duration spaceflight.

  9. Influence of Thermal Contact Resistance of Aluminum Foams in Forced Convection: Experimental Analysis

    PubMed Central

    Venettacci, Simone

    2017-01-01

    In this paper, the heat transfer performances of aluminum metal foams, placed on horizontal plane surface, was evaluated in forced convection conditions. Three different types of contacts between the sample and the heated base plate have been investigated: simple contact, brazed contact and grease paste contact. First, in order to perform the study, an ad hoc experimental set-up was built. Second, the value of thermal contact resistance was estimated. The results show that both the use of a conductive paste and the brazing contact, realized by means of a copper electro-deposition, allows a great reduction of the global thermal resistance, increasing de facto the global heat transfer coefficient of almost 80%, compared to the simple contact case. Finally, it was shown that, while the contribution of thermal resistance is negligible for the cases of brazed and grease paste contact, it is significantly high for the case of simple contact. PMID:28783052

  10. Influence of Thermal Contact Resistance of Aluminum Foams in Forced Convection: Experimental Analysis.

    PubMed

    Guarino, Stefano; Di Ilio, Giovanni; Venettacci, Simone

    2017-08-05

    In this paper, the heat transfer performances of aluminum metal foams, placed on horizontal plane surface, was evaluated in forced convection conditions. Three different types of contacts between the sample and the heated base plate have been investigated: simple contact, brazed contact and grease paste contact. First, in order to perform the study, an ad hoc experimental set-up was built. Second, the value of thermal contact resistance was estimated. The results show that both the use of a conductive paste and the brazing contact, realized by means of a copper electro-deposition, allows a great reduction of the global thermal resistance, increasing de facto the global heat transfer coefficient of almost 80%, compared to the simple contact case. Finally, it was shown that, while the contribution of thermal resistance is negligible for the cases of brazed and grease paste contact, it is significantly high for the case of simple contact.

  11. Mitigation of Resistance Through Mixtures of Traditional Pesticides, Anti-tick Vaccines, and New Acaricides Developed by the Pharmaceutical Industry

    USDA-ARS?s Scientific Manuscript database

    Over the past 70 years, the southern cattle tick, Rhipicephalus (Boophilus) microplus, has developed resistance to every acaricide available for its control. Recently, populations of R. microplus have evolved simultaneous resistance to multiple classes of acaricides. These multi-resistant population...

  12. Swimming and running through sand: resistive force theory in granular media

    NASA Astrophysics Data System (ADS)

    Goldman, Daniel

    2013-11-01

    Resistive force theory (RFT) is often used to analyze the movement of microscopic organisms swimming in fluids. In RFT, a body is partitioned into infinitesimal segments, each of which generates thrust and experiences drag. Linear superposition of forces from elements over the body allows prediction of swimming kinematics and kinetics. While RFT does not always show quantitative agreement with experimental measurements in fluids [e.g. Rodenborn et al., PNAS, 2013], we show that it quantitatively models the locomotion of animals and robots that move on and within dry granular media. RFT shows excellent agreement when the medium is slightly polydisperse, in the regime where frictional forces dominate material inertial forces, and when locomotion can be approximated as confined to a plane. Within a given plane (horizontal or vertical) relationships that govern the force versus orientation of an elemental intruder are functionally independent of the granular medium. We use RFT to explain features of locomotion-these include muscle activation patterns during sand-swimming by the sandfish lizard and optimum limb shape for legged robot walking. Work supported by NSF and ARL.

  13. Are early and late rate of force development differently influenced by fast-velocity resistance training?

    PubMed

    de Oliveira, Felipe B D; Rizatto, Guilherme F; Denadai, Benedito S

    2013-07-01

    This study examined the effect of fast-velocity concentric isokinetic resistance training (FV) on the rate of force development (RFD) at early (<100 ms) and late phases (>100 ms) of rising muscle force. Nine men participated in a 6-week resistance training intervention for the lower body, and nine matched subjects participated as controls (CON). During concentric isokinetic (180°s(-1)) knee extension training, subjects were instructed to do each contraction 'as fast and forcefully as possible'. Maximal muscle strength (MVC) and RFD (0-10, 0-20, …, 0-250 ms from the onset of contraction) were measured during maximal voluntary isometric contraction of the knee extensors (KE). There were no significant changes in MVC of KE in both groups after intervention (FV = 314·2 ± 101·1 versus 338·7 ± 88·0 N∙m, P>0·05; CON = 293·3 ± 94·8 versus 280·0 ± 72·2 N∙m, P>0·05). The RFD increased 39-71% at time intervals up to 90 ms from the onset of the contraction (P<0·05), whereas no change occurred at later time intervals. Similarly, relative RFD (i.e.%MVC∙s(-1)) (RFDr) increased 33-56% at time intervals up to 70 ms from the onset of the contraction (P<0·05). It can be concluded that a short period of resistance training performed with concentric fast-velocity isokinetic muscle contractions is able to enhance RFD and RFDr obtained at the early phase of rising muscle force.

  14. Resistance training for explosive and maximal strength: effects on early and late rate of force development.

    PubMed

    Oliveira, Felipe B D; Oliveira, Anderson S C; Rizatto, Guilherme F; Denadai, Benedito S

    2013-01-01

    The aim of the present study was to verify whether strength training designed to improve explosive and maximal strength would influence rate of force development (RFD). Nine men participated in a 6-week knee extensors resistance training program and 9 matched subjects participated as controls. Throughout the training sessions, subjects were instructed to perform isometric knee extension as fast and forcefully as possible, achieving at least 90% maximal voluntary contraction as quickly as possible, hold it for 5 s, and relax. Fifteen seconds separated each repetition (6-10), and 2 min separated each set (3). Pre- and post-training measurements were maximal isometric knee extensor (MVC), RFD, and RFD relative to MVC (i.e., %MVC·s(-1)) in different time-epochs varying from 10 to 250 ms from the contraction onset. The MVC (Nm) increased by 19% (275.8 ± 64.9 vs. 329.8 ± 60.4, p < 0.001) after training. In addition, RFD (Nm·s(-1)) increased by 22-28% at time epochs up to 20 ms from the contraction onset (0-10 ms = 1679. 1 ± 597.1 vs. 2159.2 ± 475.2, p < 0.001; 0-20 ms = 1958.79 ± 640.3 vs. 2398.4 ± 479.6, p < 0. 01), with no changes verified in later time epochs. However, no training effects on RFD were found for the training group when RFD was normalized to MVC. No changes were found in the control group. In conclusion, very early and late RFD responded differently to a short period of resistance training for explosive and maximal strength. This time-specific RFD adaptation highlight that resistance training programs should consider the specific neuromuscular demands of each sport. Key PointsThe time-specific RFD adaptation evoked by resistance training highlight that the method of analyzing RFD is essential for the interpretation of results.Confirming previous data, maximal contractile RFD and maximal force can be differently influenced by resistance training. Thus, the resistance training programs should consider the specific neuromuscular demands of each

  15. Resistance Training for Explosive and Maximal Strength: Effects on Early and Late Rate of Force Development

    PubMed Central

    Oliveira, Felipe B.D.; Oliveira, Anderson S.C.; Rizatto, Guilherme F.; Denadai, Benedito S.

    2013-01-01

    The aim of the present study was to verify whether strength training designed to improve explosive and maximal strength would influence rate of force development (RFD). Nine men participated in a 6-week knee extensors resistance training program and 9 matched subjects participated as controls. Throughout the training sessions, subjects were instructed to perform isometric knee extension as fast and forcefully as possible, achieving at least 90% maximal voluntary contraction as quickly as possible, hold it for 5 s, and relax. Fifteen seconds separated each repetition (6-10), and 2 min separated each set (3). Pre- and post-training measurements were maximal isometric knee extensor (MVC), RFD, and RFD relative to MVC (i.e., %MVC·s-1) in different time-epochs varying from 10 to 250 ms from the contraction onset. The MVC (Nm) increased by 19% (275.8 ± 64.9 vs. 329.8 ± 60.4, p < 0.001) after training. In addition, RFD (Nm·s-1) increased by 22-28% at time epochs up to 20 ms from the contraction onset (0-10 ms = 1679. 1 ± 597.1 vs. 2159.2 ± 475.2, p < 0.001; 0-20 ms = 1958.79 ± 640.3 vs. 2398.4 ± 479.6, p < 0. 01), with no changes verified in later time epochs. However, no training effects on RFD were found for the training group when RFD was normalized to MVC. No changes were found in the control group. In conclusion, very early and late RFD responded differently to a short period of resistance training for explosive and maximal strength. This time-specific RFD adaptation highlight that resistance training programs should consider the specific neuromuscular demands of each sport. Key Points The time-specific RFD adaptation evoked by resistance training highlight that the method of analyzing RFD is essential for the interpretation of results. Confirming previous data, maximal contractile RFD and maximal force can be differently influenced by resistance training. Thus, the resistance training programs should consider the specific neuromuscular demands of each sport

  16. Granular resistive force theory explains the neuromechanical phase lag during sand-swimming

    NASA Astrophysics Data System (ADS)

    Ding, Yang; Sharpe, Sarah; Goldman, Daniel

    2012-11-01

    Undulatory locomotion is a common gait used by a diversity of animals in a range of environments. This mode of locomotion is characterized by the propagation of a traveling wave of body bending, which propels the animal in the opposite direction of the wave. Previous studies of undulatory locomotion in fluids, on land, and even within sand revealed that the wave of muscle activation progresses faster than the traveling wave of curvature. This leads to an increasing phase lag between activation and curvature at more posterior segments, known as the neuromechanical phase lag. In this study, we compare biological measurements of phase lag during the sand-swimming of the sandfish lizard to predictions of a simple model of undulatory swimming that consists of prescribed kinematics and granular resistive forces. The neuromechanical phase lag measured using electromyography (EMG) quantitatively matches the predicted phase lag between the local body curvature and torque exerted by granular resistive forces. Two effects are responsible for the phase lag in this system: the yaw motion of the body and different integration length over a traveling force pattern for different positions along the body.

  17. Cyclic Fatigue Resistance and Force Generated by OneShape Instruments during Curved Canal Preparation

    PubMed Central

    Zhang, Xiaolei

    2016-01-01

    Objectives To evaluate the cyclic fatigue resistance and the force generated by OneShape files during preparation of simulated curved canals. Methods Six OneShape files (the test) and six ProTaper F2 files (the control) were subject to the bending ability test. Another thirty files of each type were used to prepare artificial canals (n = 60), which were divided into 3 groups according to respective curvatures of the canals (30°, 60°, and 90°). The numbers of cycles to fatigue (NCF) as well as the positive and negative forces that were generated by files during canal preparation were recorded. The scanning electron microscopy was applied to detect the fracture surfaces. Results Compared with ProTaper F2 files, the bending loads of OneShape files were significantly lower at deflections of 45°(P < .05), 60° (P < .05) and 75° (P < .01). No significant difference was found at 30°. OneShape files presented a higher NCF in both 60° and 90° canals than the control (P < .01). No significant difference of NCF was found between OneShape and ProTaper files in 30° canals. During the preparation of 30° canals by both files, the negative forces were dominant. With the increase of the curvature, more positive forces were observed. When the OneShape Files were compared with the control, significant different forces were found at D3 and D2 (P < .05) in 30° canals, at D2 (P < .05), D1 (P < .01) and D0 (P < .01) in 60° canals, and at D4 and D3 (P < .01) in 90° canals. Conclusions OneShape files possessed a reliable flexibility and cyclic fatigue resistance. According to the assessments of the forces generated by files, OneShape instruments performed in a more fatigue-resistant way during curved canal preparation, compared with the ProTaper F2 files. PMID:27513666

  18. What do proton motive force driven multidrug resistance transporters have in common?

    PubMed

    Mazurkiewicz, Piotr; Driessen, Arnold J M; Konings, Wil N

    2005-01-01

    The extensive progress of genome sequencing projects in recent years has demonstrated that multidrug resistance (MDR) transporters are widely spread among all domains of life. This indicates that they play crucial roles in the survival of organisms. Moreover, antibiotic and chemotherapeutic treatments have revealed that microorganisms and cancer cells may use MDR transporters to fight the cytotoxic action of drugs. Currently, several MDR extrusion systems are being investigated in detail. It is expected that understanding of the molecular basis of multidrug recognition and the transport mechanisms will allow a more rational design of new drugs which either will not be recognized and expelled by or will efficiently inhibit the activity of the MDR transporters. MDR transporters either utilize ATP hydrolysis or an ion motive force as an energy source to drive drugs out of the cell. This review summarizes the recent progress in the field of bacterial proton motive force driven MDR transporters.

  19. Predicting path from undulations for C. elegans using linear and nonlinear resistive force theory

    NASA Astrophysics Data System (ADS)

    Keaveny, Eric E.; Brown, André E. X.

    2017-04-01

    A basic issue in the physics of behaviour is the mechanical relationship between an animal and its surroundings. The model nematode C. elegans provides an excellent platform to explore this relationship due to its anatomical simplicity. Nonetheless, the physics of nematode crawling, in which the worm undulates its body to move on a wet surface, is not completely understood and the mathematical models often used to describe this phenomenon are empirical. We confirm that linear resistive force theory, one such empirical model, is effective at predicting a worm’s path from its sequence of body postures for forward crawling, reversing, and turning and for a broad range of different behavioural phenotypes observed in mutant worms. Worms recently isolated from the wild have a higher effective drag anisotropy than the laboratory-adapted strain N2 and most mutant strains. This means the wild isolates crawl with less surface slip, perhaps reflecting more efficient gaits. The drag anisotropies required to fit the observed locomotion data (70  ±  28 for the wild isolates) are significantly larger than the values measured by directly dragging worms along agar surfaces (3-10 in Rabets et al (2014 Biophys. J. 107 1980-7)). A proposed nonlinear extension of the resistive force theory model also provides accurate predictions, but does not resolve the discrepancy between the parameters required to achieve good path prediction and the experimentally measured parameters. We confirm that linear resistive force theory provides a good effective model of worm crawling that can be used in applications such as whole-animal simulations and advanced tracking algorithms, but that the nature of the physical interaction between worms and their most commonly studied laboratory substrate remains unresolved.

  20. Unraveling the genetic driving forces enabling antibiotic resistance at the single cell level

    NASA Astrophysics Data System (ADS)

    Bos, Julia

    Bacteria are champions at finding ways to quickly respond and adapt to environments like the human gut, known as the epicentre of antibiotic resistance. How do they do it? Combining molecular biology tools to microfluidic and fluorescence microscopy technologies, we monitor the behavior of bacteria at the single cell level in the presence of non-toxic doses of antibiotics. By tracking the chromosome dynamics of Escherichia coli cells upon antibiotic treatment, we examine the changes in the number, localization and content of the chromosome copies within one cell compartment or between adjacent cells. I will discuss how our work pictures the bacterial genomic plasticity as a driving force in evolution and how it provides access to the mechanisms controlling the subtle balance between genetic diversity and stability in the development of antibiotic resistance.

  1. 76 FR 63927 - Interagency Task Force on Antimicrobial Resistance (ITFAR): An Update on A Public Health Action...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-14

    ... Resistance (ITFAR): An Update on A Public Health Action Plan to Combat Antimicrobial Resistance AGENCY... report on progress by Federal agencies in accomplishing activities outlined in A Public Health Action... (AR) in recognition of the increasing importance of AR as a public health threat. The Task Force is co...

  2. Forced magnetic reconnection in a plasma sheet with localized resistivity profile excited by lower hybrid drift type instability

    NASA Technical Reports Server (NTRS)

    Hoshino, M.

    1991-01-01

    A forced magnetic reconnection process with a temporal evolution of resistivity is studied for a plasma sheet with a nonuniform resistivity profile based on the nonlocal mode structure of the lower hybrid drift type instability. The growth rate of the mode found is almost independent of the resistivity at the neutral sheet, but depends on the resistivity of the region of maximum density gradient away from the neutral sheet. This is studied by using both a nonlinear numerical MHD simulation and a linear theory. The mode may be relevant to the prevalent theoretical concept of MHD reconnection and the localized anomalous resistivity profile based on the lower hybrid drift instability.

  3. Plan to combat extensively drug-resistant tuberculosis: recommendations of the Federal Tuberculosis Task Force.

    PubMed

    2009-02-13

    An estimated one third of the world's population is infected with Mycobacterium tuberculosis, and nearly 9 million persons develop disease caused by M. tuberculosis each year. Although tuberculosis (TB) occurs predominantly in resource-limited countries, it also occurs in the United States. During 1985-1992, the United States was confronted with an unprecedented TB resurgence. This resurgence was accompanied by a rise in multidrug-resistant TB (MDR TB), which is defined as TB that is resistant to the two most effective first-line therapeutic drugs, isoniazid and rifampin. In addition, virtually untreatable strains of M. tuberculosis are emerging globally. Extensively drug-resistant (XDR) TB is defined as MDR TB that also is resistant to the most effective second-line therapeutic drugs used commonly to treat MDR TB: fluoroquinolones and at least one of three injectable second-line drugs used to treat TB (amikacin, kanamycin, or capreomycin). XDR TB has been identified in all regions of the world, including the United States. In the United States, the cost of hospitalization for one XDR TB patient is estimated to average $483,000, approximately twice the cost for MDR TB patients. Because of the limited responsiveness of XDR TB to available antibiotics, mortality rates among patients with XDR TB are similar to those of TB patients in the preantibiotic era. In January 1992, CDC convened a Federal TB Task Force to draft an action plan to improve prevention and control of drug-resistant TB in the United States (CDC. National action plan to combat multidrug-resistant tuberculosis. MMWR 1992;41([No. RR-11]). In November 2006, CDC reconvened the Task Force to draft an updated action plan to address the issue of MDR TB and XDR TB. Task Force members were divided into nine response areas and charged with articulating the most pressing problems, identifying barriers to improvement, and recommending specific action steps to improve prevention and control of XDR TB within their

  4. Mitigation of Insulin Resistance by Mangiferin in a Rat Model of Fructose-Induced Metabolic Syndrome Is Associated with Modulation of CD36 Redistribution in the Skeletal Muscle.

    PubMed

    Zhou, Liang; Pan, Yongquan; Chonan, Ritsu; Batey, Robert; Rong, Xianglu; Yamahara, Johji; Wang, Jianwei; Li, Yuhao

    2016-01-01

    Mangiferin is one of the prominent active components responsible for the antidiabetic property of many traditional herbs, but its underlying mechanisms of action remain unclear. CD36 in skeletal muscle is known to contribute to the etiology of insulin resistance by facilitating fatty acid uptake. This study investigated the effect of mangiferin on insulin resistance. The results showed that treatment of Wistar-Kyoto rats with mangiferin (15 mg/kg, once daily, by oral gavage) for 7 weeks inhibited chronic liquid fructose consumption-induced increases in plasma insulin concentrations at the baseline and during oral glucose tolerance test (OGTT), and the homeostasis model assessment of insulin resistance index. It also suppressed the increases in fasted plasma nonesterified fatty acid (NEFA) concentration and the adipose tissue insulin resistance index. Mechanistically, mangiferin neither affected intakes of fructose and chow, and the increase in epididymal and perirenal fat, nor attenuated fructose-induced hypertension. In contrast, mangiferin attenuated fructose-induced acceleration of plasma NEFA clearance during OGTT, and tended to decrease excessive triglyceride accumulation in gastrocnemius. Immunofluorescence staining and subsequent rating of CD36-expressing fibers in gastrocnemius revealed that mangiferin restored fructose-stimulated sarcolemmal CD36 overexpression and decreased intracellular CD36 distribution. In addition, the effects of mangiferin on the parameters associated with insulin resistance and abnormal fatty acid metabolism were absent in the spontaneously hypertensive rats carrying numerous nonfunctional mutations in the CD36 gene. Thus, these results suggest that mangiferin treatment mitigates insulin resistance in a rat model of fructose-induced metabolic syndrome by modulating sarcolemmal and intracellular CD36 redistribution in the skeletal muscle. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

  5. Antidiabetogenic effects of chromium mitigate hyperinsulinemia-induced cellular insulin resistance via correction of plasma membrane cholesterol imbalance.

    PubMed

    Horvath, Emily M; Tackett, Lixuan; McCarthy, Alicia M; Raman, Priya; Brozinick, Joseph T; Elmendorf, Jeffrey S

    2008-04-01

    Previously, we found that a loss of plasma membrane (PM) phosphatidylinositol 4,5-bisphosphate (PIP2)-regulated filamentous actin (F-actin) structure contributes to insulin-induced insulin resistance. Interestingly, we also demonstrated that chromium picolinate (CrPic), a dietary supplement thought to improve glycemic status in insulin-resistant individuals, augments insulin-regulated glucose transport in insulin-sensitive 3T3-L1 adipocytes by lowering PM cholesterol. Here, to gain mechanistic understanding of these separate observations, we tested the prediction that CrPic would protect against insulin-induced insulin resistance by improving PM features important in cytoskeletal structure and insulin sensitivity. We found that insulin-induced insulin-resistant adipocytes display elevated PM cholesterol with a reciprocal decrease in PM PIP2. This lipid imbalance and insulin resistance was corrected by the cholesterol-lowering action of CrPic. The PM lipid imbalance did not impair insulin signaling, nor did CrPic amplify insulin signal transduction. In contrast, PM analyses corroborated cholesterol and PIP2 interactions influencing cytoskeletal structure. Because extensive in vitro study documents an essential role for cytoskeletal capacity in insulin-regulated glucose transport, we next evaluated intact skeletal muscle from obese, insulin-resistant Zucker (fa/fa) rats. Because insulin resistance in these animals likely involves multiple mechanisms, findings that cholesterol-lowering restored F-actin cytoskeletal structure and insulin sensitivity to that witnessed in lean control muscle were striking. Also, experiments using methyl-beta-cyclodextrin to shuttle cholesterol into or out of membranes respectively recapitulated the insulin-induced insulin-resistance and protective effects of CrPic on membrane/cytoskeletal interactions and insulin sensitivity. These data predict a PM cholesterol basis for hyperinsulinemia-associated insulin resistance and importantly

  6. Antidiabetogenic Effects of Chromium Mitigate Hyperinsulinemia-Induced Cellular Insulin Resistance via Correction of Plasma Membrane Cholesterol Imbalance

    PubMed Central

    Horvath, Emily M.; Tackett, Lixuan; McCarthy, Alicia M.; Raman, Priya; Brozinick, Joseph T.; Elmendorf, Jeffrey S.

    2008-01-01

    Previously, we found that a loss of plasma membrane (PM) phosphatidylinositol 4,5-bisphosphate (PIP2)-regulated filamentous actin (F-actin) structure contributes to insulin-induced insulin resistance. Interestingly, we also demonstrated that chromium picolinate (CrPic), a dietary supplement thought to improve glycemic status in insulin-resistant individuals, augments insulin-regulated glucose transport in insulin-sensitive 3T3-L1 adipocytes by lowering PM cholesterol. Here, to gain mechanistic understanding of these separate observations, we tested the prediction that CrPic would protect against insulin-induced insulin resistance by improving PM features important in cytoskeletal structure and insulin sensitivity. We found that insulin-induced insulin-resistant adipocytes display elevated PM cholesterol with a reciprocal decrease in PM PIP2. This lipid imbalance and insulin resistance was corrected by the cholesterol-lowering action of CrPic. The PM lipid imbalance did not impair insulin signaling, nor did CrPic amplify insulin signal transduction. In contrast, PM analyses corroborated cholesterol and PIP2 interactions influencing cytoskeletal structure. Because extensive in vitro study documents an essential role for cytoskeletal capacity in insulin-regulated glucose transport, we next evaluated intact skeletal muscle from obese, insulin-resistant Zucker (fa/fa) rats. Because insulin resistance in these animals likely involves multiple mechanisms, findings that cholesterol-lowering restored F-actin cytoskeletal structure and insulin sensitivity to that witnessed in lean control muscle were striking. Also, experiments using methyl-β-cyclodextrin to shuttle cholesterol into or out of membranes respectively recapitulated the insulin-induced insulin-resistance and protective effects of CrPic on membrane/cytoskeletal interactions and insulin sensitivity. These data predict a PM cholesterol basis for hyperinsulinemia-associated insulin resistance and importantly

  7. Empirical resistive-force theory for slender biological filaments in shear-thinning fluids.

    PubMed

    Riley, Emily E; Lauga, Eric

    2017-06-01

    Many cells exploit the bending or rotation of flagellar filaments in order to self-propel in viscous fluids. While appropriate theoretical modeling is available to capture flagella locomotion in simple, Newtonian fluids, formidable computations are required to address theoretically their locomotion in complex, nonlinear fluids, e.g., mucus. Based on experimental measurements for the motion of rigid rods in non-Newtonian fluids and on the classical Carreau fluid model, we propose empirical extensions of the classical Newtonian resistive-force theory to model the waving of slender filaments in non-Newtonian fluids. By assuming the flow near the flagellum to be locally Newtonian, we propose a self-consistent way to estimate the typical shear rate in the fluid, which we then use to construct correction factors to the Newtonian local drag coefficients. The resulting non-Newtonian resistive-force theory, while empirical, is consistent with the Newtonian limit, and with the experiments. We then use our models to address waving locomotion in non-Newtonian fluids and show that the resulting swimming speeds are systematically lowered, a result which we are able to capture asymptotically and to interpret physically. An application of the models to recent experimental results on the locomotion of Caenorhabditis elegans in polymeric solutions shows reasonable agreement and thus captures the main physics of swimming in shear-thinning fluids.

  8. Empirical resistive-force theory for slender biological filaments in shear-thinning fluids

    NASA Astrophysics Data System (ADS)

    Riley, Emily E.; Lauga, Eric

    2017-06-01

    Many cells exploit the bending or rotation of flagellar filaments in order to self-propel in viscous fluids. While appropriate theoretical modeling is available to capture flagella locomotion in simple, Newtonian fluids, formidable computations are required to address theoretically their locomotion in complex, nonlinear fluids, e.g., mucus. Based on experimental measurements for the motion of rigid rods in non-Newtonian fluids and on the classical Carreau fluid model, we propose empirical extensions of the classical Newtonian resistive-force theory to model the waving of slender filaments in non-Newtonian fluids. By assuming the flow near the flagellum to be locally Newtonian, we propose a self-consistent way to estimate the typical shear rate in the fluid, which we then use to construct correction factors to the Newtonian local drag coefficients. The resulting non-Newtonian resistive-force theory, while empirical, is consistent with the Newtonian limit, and with the experiments. We then use our models to address waving locomotion in non-Newtonian fluids and show that the resulting swimming speeds are systematically lowered, a result which we are able to capture asymptotically and to interpret physically. An application of the models to recent experimental results on the locomotion of Caenorhabditis elegans in polymeric solutions shows reasonable agreement and thus captures the main physics of swimming in shear-thinning fluids.

  9. Effects of resistance training on tendon mechanical properties and rapid force production in prepubertal children.

    PubMed

    Waugh, C M; Korff, T; Fath, F; Blazevich, A J

    2014-08-01

    Children develop lower levels of muscle force, and at slower rates, than adults. Although strength training in children is expected to reduce this differential, a synchronous adaptation in the tendon must be achieved to ensure forces continue to be transmitted to the skeleton with efficiency while minimizing the risk of strain-related tendon injury. We hypothesized that resistance training (RT) would alter tendon mechanical properties in children concomitantly with changes in force production characteristics. Twenty prepubertal children (age 8.9 ± 0.3 yr) were equally divided into control (nontraining) and experimental (training) groups. The training group completed a 10-wk RT intervention consisting of 2-3 sets of 8-15 plantar flexion contractions performed twice weekly on a recumbent calf-raise machine. Achilles tendon properties (cross-sectional area, elongation, stress, strain, stiffness, and Young's modulus), electromechanical delay (EMD; time between the onset of muscle activity and force), rate of force development (RFD; slope of the force-time curve), and rate of electromyographic (EMG) increase (REI; slope of the EMG time curve) were measured before and after RT. Tendon stiffness and Young's modulus increased significantly after RT in the experimental group only (∼29% and ∼25%, respectively); all other tendon properties were not significantly altered, although there were mean decreases in both peak tendon strain and strain at a given force level (14% and 24%, respectively; not significant) which may have implications for tendon injury risk and muscle fiber mechanics. A decrease of ∼13% in EMD was found after RT for the experimental group, which paralleled the increase in tendon stiffness (r = -0.59); however, RFD and REI were unchanged. The present data show that the Achilles tendon adapts to RT in prepubertal children and is paralleled by a change in EMD, although the magnitude of this change did not appear to be sufficient to influence RFD. These

  10. Increase in Mechanical Resistance to Force in a Shear-Activated Protein

    NASA Astrophysics Data System (ADS)

    Botello, Eric; Harris, Nolan; Choi, Huiwan; Zhou, Zhou; Bergeron, Angela; Dong, Jing-Fei; Kiang, Ching-Hwa

    2009-03-01

    von Willebrand factor (VWF) is the largest multimeric adhesion ligand found in human blood. Plasma VWF (pVWF) must be exposed to shear stress, like at sites of vascular injury, to be activated to bind platelets to induce blood clotting. In addition, adhesion activity of VWF is related to its polymer size, with the ultra-large form of VWF (ULVWF) being hyper-active, and forming fibers even without exposure to shear stress. We used the AFM to stretch pVWF, sheared VWF (sVWF) and ULVWF, and monitor the forces as a function of molecular extension. We showed a similar increase in force resistance to unfolding for sVWF and ULVWF when compared to pVWF. The increase in force is reduced when other molecules that are known to disrupt their fibril formation are present. Our results provide evidence that the common higher order structure of sVWF and ULVWF may affect the domain structure that causes difference in their adhesion activity compared to pVWF.

  11. Effects of fast-velocity eccentric resistance training on early and late rate of force development.

    PubMed

    Oliveira, Anderson Souza; Corvino, Rogério Bulhões; Caputo, Fabrizio; Aagaard, Per; Denadai, Benedito Sérgio

    2016-01-01

    This study examined whether short-term maximal resistance training employing fast-velocity eccentric knee extensor actions would induce improvements in maximal isometric torque and rate of force development (RFD) at early (<100 ms) and late phases (>100 ms) of rising torque. Twenty healthy men were assigned to two experimental groups: eccentric resistance training (TG) or control (CG). Participants on the TG trained three days a week for a total of eight weeks. Training consisted of maximal unilateral eccentric knee extensors actions performed at 180 °s-1. Maximal isometric knee extensor torque (MVC) and incremental RFD in successive 50 ms time-windows from the onset contraction were analysed in absolute terms (RFDINC) or when normalised relative to MVC (RFDREL). After eight weeks, TG demonstrated increases in MVC (28%), RFDINC (0-50 ms: 30%; 50-100 ms: 31%) and RFDREL (0-50 ms: 29%; 50-100 ms: 32%). Moreover, no changes in the late phase of incremental RFD were observed in TG. No changes were found in the CG. In summary, we have demonstrated, in active individuals, that a short period of resistance training performed with eccentric fast-velocity isokinetic muscle contractions is able to enhance RFDINC and RFDREL obtained at the early phase of rising joint torque.

  12. Surface-mediated chromate-resistant mechanism of Enterobacter cloacae bacteria investigated by atomic force microscopy.

    PubMed

    Yang, Chunpeng; Cheng, Yangjian; Ma, Xiaoyan; Zhu, Ying; Holman, Hoi-Ying; Lin, Zhang; Wang, Chen

    2007-04-10

    The Enterobacter cloacae CYS-25 strain isolated from a chromate plant shows a strong capability for chromate resistance instead of chromate reduction in aerobic conditions. In this study, atomic force microscopy (AFM) was used for studying the morphology characteristics of bacterial properties during the chromate resistance process. The average length of E. cloacae bacteria in the stationary phase is about 2.3 +/- 0.6 microm, while under the stimulation of 400 mg/L CrO42-, the length of bacteria increases to 3.2 +/- 0.7 microm. Height and phase images showed that, with the addition of CrO42-, the smooth surface of bacteria changed into one with discontinuous features with characteristic dimension of 40-200 nm. Analysis reveals that these compact convex patches are organic components stimulated by CrO42-. A chromate resistance mechanism relating to the overexpression of extracellular biologic components for preventing the permeability of CrO42- into the cell is proposed as the survival strategy of E. cloacae in chromate situation.

  13. Mitigation strategy

    NASA Astrophysics Data System (ADS)

    Carusi, Andrea; Perozzi, Ettore; Scholl, Hans

    2005-04-01

    There are three major options for mitigation of Near Earth Objects (NEOs). Deflection and disruption of NEOs require the development of new space technologies. A third option, the preparation of the target area on Earth to mitigate an impact, needs institutions for the required civil defense measures. The three options are complementary. Basic requirements for the presently most preferred strategy, deflection, are presented. To cite this article: A. Carusi et al., C. R. Physique 6 (2005).

  14. Novel reverse osmosis membranes composed of modified PVA/Gum Arabic conjugates: Biofouling mitigation and chlorine resistance enhancement.

    PubMed

    Falath, Wail; Sabir, Aneela; Jacob, Karl I

    2017-01-02

    A novel crosslinked Poly (vinyl alcohol) (PVA) reverse osmosis (RO) thin film membrane conjugated with Gum Arabic (GA) with superb performance and features was synthesized for water desalination. RO membrane desalination parameters, such as hydrophilicity, surface roughness, water permeability, salt rejection, Chlorine resistance and biofouling resistance were evaluated using a dead end RO filtration unit. The incorporation of Pluronic F127 and the conjugation of Gum Arabic improved the overall RO performance of the membranes. This study has shown that the membrane PVA-GA-5 that contains 0.9wt% Gum Arabic provided excellent permeation, salt rejection, Chlorine and biofouling resistance and mechanical strength. The most remarkable result to arise from this research is that the overall RO performance enhancement has been achieved while utilizing PVA/Gum Arabic as a separation layer without the use of a substrate, which eliminates negative effects associated with the use of a substrate like internal concentration polarization. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Atomic force microscopy study of the antibacterial effect of fosfomycin on methicillin-resistant Staphylococcus pseudintermedius

    NASA Astrophysics Data System (ADS)

    Neethirajan, Suresh; DiCicco, Matthew

    2014-08-01

    The influence of fosfomycin on methicillin-resistant Staphylococcus pseudintermedius (MRSP) as the target cell was studied by atomic force microscopy (AFM). Nanoscale images of the effects of the antibiotic fosfomycin on this gram-positive bacterium's cell were obtained in situ without fixing agents. Our study has demonstrated substantial morphological and topographical differences between the control and fosfomycin-treated MRSP cells. The AFM investigations further revealed the rough surface morphology and a 30 % shrinkage in size of the fosfomycin-treated cell and the leakage of cytoplasmic components from the cell. The damage of cell membrane integrity and the cell surface degradation as observed elaborates the antibacterial activity of fosfomycin. The AFM image analysis also reveals that the fosfomycin inhibits cell division, and prevents the adhesion on the surface discouraging the biofilm attachment. The micro-titre plate assay results conform to the atomic force microscopy image analysis. This is the first visual demonstration of the effect of fosfomycin on MRSP cells.

  16. Comparison of physical, numerical and resistive force models of undulatory locomotion within granular media

    NASA Astrophysics Data System (ADS)

    Goldman, Daniel I.; Maladen, Ryan D.; Ding, Yang; Umbanhowar, Paul

    2010-11-01

    We integrate biological experiments, empirical theory, numerical simulation, and a physical robot model to reveal principles of undulatory locomotion in granular media. High speed x-ray imaging of the sandfish, Scincus scincus, in 3 mm glass particles reveals that it swims within the medium without limb use by propagating a single period traveling sinusoidal wave down its body, resulting in a wave efficiency, η, the ratio of its average forward speed to wave speed, of 0.54,,.13. A resistive force theory (RFT) which balances granular thrust and drag forces along the body predicts η close to the observed value. We test this prediction against two other modeling approaches: a numerical model of the sandfish coupled to a Molecular Dynamics (MD) simulation of the granular medium, and an undulatory robot which swims within granular media. We use these models and analytic solutions of the RFT to vary the ratio of undulation amplitude to wavelength (A/λ) and demonstrate an optimal condition for sand-swimming that results from competition between η and λ. The RFT, in agreement with simulation and robot models, predicts that for a single period sinusoidal wave, maximal speed occurs for A/λ 0.2, the same kinematics used by the sandfish.

  17. In situ imaging of detergent-resistant membranes by atomic force microscopy.

    PubMed

    Giocondi, M C; Vié, V; Lesniewska, E; Goudonnet, J P; Le Grimellec, C

    2000-07-01

    Purified detergent-resistant membranes (DRMs) are powerful tools for the biochemical study of plasma membrane domains. To what extent these isolated DRMs correspond to native membrane domains remains, however, a matter of debate. The most immediate question to be answered concerns the in situ size range of DRMs, a determination that escapes classical microscopy techniques. In this study we show that in situ three-dimensional images of a material as fragile as Triton X-100-treated cells can be obtained, in buffer, by tapping mode atomic force microscopy. These images establish that, prior to the isolation procedure, the detergent plasma membrane fragments form domains whose size frequently exceeds 15-20 microm(2). This DRMs size range is about 1 order of magnitude higher than that estimated for the larger microdomains of living cells, which strongly suggests that membrane microdomains rearrange into larger DRMs during Triton X-100 treatment. Concomitantly, the images also reveal the presence of the cytoskeleton, which is resistant to detergent extraction, and suggest that, in situ, DRMs are associated with the membrane cytoskeleton. Copyright 2000 Academic Press.

  18. Evaluation of the nanotube intrinsic resistance across the tip-carbon nanotube-metal substrate junction by Atomic Force Microscopy

    PubMed Central

    2011-01-01

    Using an atomic force microscope (AFM) at a controlled contact force, we report the electrical signal response of multi-walled carbon nanotubes (MWCNTs) disposed on a golden thin film. In this investigation, we highlight first the theoretical calculation of the contact resistance between two types of conductive tips (metal-coated and doped diamond-coated), individual MWCNTs and golden substrate. We also propose a circuit analysis model to schematize the «tip-CNT-substrate» junction by means of a series-parallel resistance network. We estimate the contact resistance R of each contribution of the junction such as Rtip-CNT, RCNT-substrate and Rtip-substrate by using the Sharvin resistance model. Our final objective is thus to deduce the CNT intrinsic radial resistance taking into account the calculated electrical resistance values with the global resistance measured experimentally. An unwished electrochemical phenomenon at the tip apex has also been evidenced by performing measurements at different bias voltages with diamond tips. For negative tip-substrate bias, a systematic degradation in color and contrast of the electrical cartography occurs, consisting of an important and non-reversible increase of the measured resistance. This effect is attributed to the oxidation of some amorphous carbon areas scattered over the diamond layer covering the tip. For a direct polarization, the CNT and substrate surface can in turn be modified by an oxidation mechanism. PMID:21711904

  19. Evaluation of the nanotube intrinsic resistance across the tip-carbon nanotube-metal substrate junction by Atomic Force Microscopy.

    PubMed

    Dominiczak, Maguy; Otubo, Larissa; Alamarguy, David; Houzé, Frédéric; Volz, Sebastian; Noël, Sophie; Bai, Jinbo

    2011-04-14

    Using an atomic force microscope (AFM) at a controlled contact force, we report the electrical signal response of multi-walled carbon nanotubes (MWCNTs) disposed on a golden thin film. In this investigation, we highlight first the theoretical calculation of the contact resistance between two types of conductive tips (metal-coated and doped diamond-coated), individual MWCNTs and golden substrate. We also propose a circuit analysis model to schematize the «tip-CNT-substrate» junction by means of a series-parallel resistance network. We estimate the contact resistance R of each contribution of the junction such as Rtip-CNT, RCNT-substrate and Rtip-substrate by using the Sharvin resistance model. Our final objective is thus to deduce the CNT intrinsic radial resistance taking into account the calculated electrical resistance values with the global resistance measured experimentally. An unwished electrochemical phenomenon at the tip apex has also been evidenced by performing measurements at different bias voltages with diamond tips. For negative tip-substrate bias, a systematic degradation in color and contrast of the electrical cartography occurs, consisting of an important and non-reversible increase of the measured resistance. This effect is attributed to the oxidation of some amorphous carbon areas scattered over the diamond layer covering the tip. For a direct polarization, the CNT and substrate surface can in turn be modified by an oxidation mechanism.

  20. A Built-In Mechanism to Mitigate the Spread of Insect-Resistance and Herbicide-Tolerance Transgenes into Weedy Rice Populations

    PubMed Central

    Liu, Chengyi; Li, Jingjing; Gao, Jianhua; Shen, Zhicheng; Lu, Bao-Rong; Lin, Chaoyang

    2012-01-01

    Background The major challenge of cultivating genetically modified (GM) rice (Oryza sativa) at the commercial scale is to prevent the spread of transgenes from GM cultivated rice to its coexisting weedy rice (O. sativa f. spontanea). The strategic development of GM rice with a built-in control mechanism can mitigate transgene spread in weedy rice populations. Methodology/Principal Findings An RNAi cassette suppressing the expression of the bentazon detoxifying enzyme CYP81A6 was constructed into the T-DNA which contained two tightly linked transgenes expressing the Bt insecticidal protein Cry1Ab and the glyphosate tolerant 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), respectively. GM rice plants developed from this T-DNA were resistant to lepidopteran pests and tolerant to glyphosate, but sensitive to bentazon. The application of bentazon of 2000 mg/L at the rate of 40 mL/m2, which is approximately the recommended dose for the field application to control common rice weeds, killed all F2 plants containing the transgenes generated from the Crop-weed hybrids between a GM rice line (CGH-13) and two weedy rice strains (PI-63 and PI-1401). Conclusions/Significance Weedy rice plants containing transgenes from GM rice through gene flow can be selectively killed by the spray of bentazon when a non-GM rice variety is cultivated alternately in a few-year interval. The built-in control mechanism in combination of cropping management is likely to mitigate the spread of transgenes into weedy rice populations. PMID:22359609

  1. 32 CFR 989.22 - Mitigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Mitigation. 989.22 Section 989.22 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION... suggesting mitigation measures. Both the public and the Air Force community need to know what commitments are...

  2. 32 CFR 989.22 - Mitigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Mitigation. 989.22 Section 989.22 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION... suggesting mitigation measures. Both the public and the Air Force community need to know what commitments are...

  3. 32 CFR 989.22 - Mitigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Mitigation. 989.22 Section 989.22 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION... suggesting mitigation measures. Both the public and the Air Force community need to know what commitments are...

  4. 32 CFR 989.22 - Mitigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Mitigation. 989.22 Section 989.22 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION... suggesting mitigation measures. Both the public and the Air Force community need to know what commitments are...

  5. Stability of nonuniform rotations of Lagrange's gyroscope about the main axis in the presence of medium resistance forces

    NASA Astrophysics Data System (ADS)

    Puzyrev, V. E.

    Sufficient conditions are obtained for the asymptotic stability of nonuniform rotations of a symmetric heavy rigid body about the principal inertia axis in the presence of medium resistance forces. In contrast to the case previously investigated by Matrosov (1962), the dissipation function is not necessarily positive definite.

  6. 75 FR 52751 - Office of Global Health Affairs; Trans-Atlantic Task Force on Antimicrobial Resistance (TATFAR)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-27

    ... force to focus ``on urgent antimicrobial resistance issues focused on appropriate therapeutic use of... three focus areas of the TATFAR as defined in the 2009 EU/US Summit Declaration: Appropriate therapeutic... clearly identify ``TATFAR Comments'' as the subject. 3. Building and Security Guidelines The meeting is...

  7. Atomic Force Microscopy Reveals Important Differences in Axonal Resistance to Injury

    PubMed Central

    Magdesian, Margaret H.; Sanchez, Fernando S.; Lopez, Monserratt; Thostrup, Peter; Durisic, Nela; Belkaid, Wiam; Liazoghli, Dalinda; Grütter, Peter; Colman, David R.

    2012-01-01

    Axonal degeneration after traumatic brain injury and nerve compression is considered a common underlying cause of temporary as well as permanent disability. Because a proper functioning of neural network requires phase coherence of all components, even subtle changes in circuitry may lead to network failure. However, it is still not possible to determine which axons will recover or degenerate after injury. Several groups have studied the pressure threshold for axonal injury within a nerve, but difficulty accessing the injured region; insufficient imaging methods and the extremely small dimensions involved have prevented the evaluation of the response of individual axons to injury. We combined microfluidics with atomic force microscopy and in vivo imaging to estimate the threshold force required to 1), uncouple axonal transport without impairing axonal survival, and 2), compromise axonal survival in both individual and bundled axons. We found that rat hippocampal axons completely recover axonal transport with no detectable axonal loss when compressed with pressures up to 65 ± 30 Pa for 10 min, while dorsal root ganglia axons can resist to pressures up to 540 ± 220 Pa. We investigated the reasons for the differential susceptibility of hippocampal and DRG axons to mechanical injury and estimated the elasticity of live axons. We found that dorsal root ganglia axons have a 20% lower elastic modulus than hippocampal axons. Our results emphasize the importance of the integrity of the axonal cytoskeleton in deciding the axonal fate after damage and open up new avenues to improve injury diagnosis and to identify ways to protect axons. PMID:22947856

  8. Adipocyte-specific CD1d-deficiency mitigates diet-induced obesity and insulin resistance in mice

    PubMed Central

    Satoh, Masashi; Hoshino, Miyuki; Fujita, Koki; Iizuka, Misao; Fujii, Satoshi; Clingan, Christopher S.; Van Kaer, Luc; Iwabuchi, Kazuya

    2016-01-01

    It has been shown that CD1d expression and glycolipid-reactive, CD1d-restricted NKT cells exacerbate the development of obesity and insulin resistance in mice. However, the relevant CD1d-expressing cells that influence the effects of NKT cells on the progression of obesity remain incompletely defined. In this study, we have demonstrated that 3T3-L1 adipocytes can present endogenous ligands to NKT cells, leading to IFN-γ production, which in turn, stimulated 3T3-L1 adipocytes to enhance expression of CD1d and CCL2, and decrease expression of adiponectin. Furthermore, adipocyte-specific CD1d deletion decreased the size of the visceral adipose tissue mass and enhanced insulin sensitivity in mice fed a high-fat diet (HFD). Accordingly, NKT cells were less activated, IFN-γ production was significantly reduced, and levels of adiponectin were increased in these animals as compared with control mice on HFD. Importantly, macrophage recruitment into the adipose tissue of adipocyte-specific CD1d-deficient mice was significantly blunted. These findings indicate that interactions between NKT cells and CD1d-expressing adipocytes producing endogenous NKT cell ligands play a critical role in the induction of inflammation and functional modulation of adipose tissue that leads to obesity. PMID:27329323

  9. Report of the Error and Emittance Task Force on the superconducting super collider: Part 1, Resistive machines

    SciTech Connect

    1993-10-01

    A review of the design and specifications of the resistive accelerators in the SSC complex was conducted during the past year. This review was initiated in response to a request from the SSC Project Manager. The Error and Emittance Task Force was created October 30, 1992, and charged with reviewing issues associated with the specification of errors and tolerances throughout the injector chain and in the Collider, and to optimize the global error budget. Effects which directly impact the emittance budget were of prime importance. The Task Force responded to three charges: Examination of the resistive accelerators and their injection and extraction systems; examination of the connecting beamlines and the overall approach taken in their design; and global filling, timing, and synchronization issues. The High Energy Booster and the Collider were deemed to be sufficiently different from the resistive accelerators that it was decided to treat them as a separate group. They will be the subject of a second part to this report.

  10. Pronounced energy restriction with elevated protein intake results in no change in proteolysis and reductions in skeletal muscle protein synthesis that are mitigated by resistance exercise.

    PubMed

    Hector, Amy J; McGlory, Chris; Damas, Felipe; Mazara, Nicole; Baker, Steven K; Phillips, Stuart M

    2017-09-12

    Preservation of lean body mass (LBM) may be important during dietary energy restriction (ER) and requires equal rates of muscle protein synthesis (MPS) and muscle protein breakdown (MPB). Currently, the relative contribution of MPS and MPB to the loss of LBM during ER in humans is unknown. We aimed to determine the impact of dietary protein intake and resistance exercise on MPS and MPB during a controlled short-term energy deficit. Adult men (body mass index, 28.6 ± 0.6 kg/m(2); age 22 ± 1 yr) underwent 10 d of 40%-reduced energy intake while performing unilateral resistance exercise and consuming lower protein (1.2 g/kg/d, n = 12) or higher protein (2.4 g/kg per d, n = 12). Pre- and postintervention testing included dual-energy X-ray absorptiometry, primed constant infusion of ring-[(13)C6]phenylalanine, and (15)[N]phenylalanine to measure acute postabsorptive MPS and MPB; D2O to measure integrated MPS; and gene and protein expression. There was a decrease in acute MPS after ER (higher protein, 0.059 ± 0.006 to 0.051 ± 0.009%/h; lower protein, 0.061 ± 0.005-0.045 ± 0.006%/h; P < 0.05) that was attenuated with resistance exercise (higher protein, 0.067 ± 0.01%/h; lower protein, 0.061 ± 0.006%/h), and integrated MPS followed a similar pattern. There was no change in MPB (energy balance, 0.080 ± 0.01%/hr; ER rested legs, 0.078 ± 0.008%/hr; ER exercised legs, 0.079 ± 0.006%/hr). We conclude that a reduction in MPS is the main mechanism that underpins LBM loss early in ER in adult men.-Hector, A. J., McGlory, C., Damas, F., Mazara, N., Baker, S. K., Phillips, S. M. Pronounced energy restriction with elevated protein intake results in no change in proteolysis and reductions in skeletal muscle protein synthesis that are mitigated by resistance exercise. © FASEB.

  11. Force production during squats performed with a rotational resistance device under stable versus unstable conditions

    PubMed Central

    Moras, Gerard; Vázquez-Guerrero, Jairo

    2015-01-01

    [Purpose] Force production during a squat action on a rotational resistance device (RRD) under stable and unstable conditions. [Subjects and Methods] Twenty-one healthy males were asked to perform six sets of six repetitions of squats on an RRD on either stable or unstable surfaces. The stable and unstable sets were performed on different days. Muscular outputs were obtained from a linear encoder and a strain gauge fixed to a vest. [Results] Overall, the results showed no significant differences for any of the dependent variables across exercise modes. Forcemean outputs were higher in the concentric phase than in the eccentric phase for each condition, but there were no differences in velocity, time or displacement. The forcepeak was similar in the eccentric and concentric phases of movement under both stable and unstable conditions. There were no significant differences in forcemean between sets per condition or between conditions. [Conclusion] These results suggest that performing squats with a RRD achieves similar forcemean and forcepeak under stable and unstable conditions. The forcepeak produced is also similar in concentric and eccentric phases. PMID:26696707

  12. Force production during squats performed with a rotational resistance device under stable versus unstable conditions.

    PubMed

    Moras, Gerard; Vázquez-Guerrero, Jairo

    2015-11-01

    [Purpose] Force production during a squat action on a rotational resistance device (RRD) under stable and unstable conditions. [Subjects and Methods] Twenty-one healthy males were asked to perform six sets of six repetitions of squats on an RRD on either stable or unstable surfaces. The stable and unstable sets were performed on different days. Muscular outputs were obtained from a linear encoder and a strain gauge fixed to a vest. [Results] Overall, the results showed no significant differences for any of the dependent variables across exercise modes. Forcemean outputs were higher in the concentric phase than in the eccentric phase for each condition, but there were no differences in velocity, time or displacement. The forcepeak was similar in the eccentric and concentric phases of movement under both stable and unstable conditions. There were no significant differences in forcemean between sets per condition or between conditions. [Conclusion] These results suggest that performing squats with a RRD achieves similar forcemean and forcepeak under stable and unstable conditions. The forcepeak produced is also similar in concentric and eccentric phases.

  13. Emergence of the advancing neuromechanical phase in a resistive force dominated medium

    PubMed Central

    Ding, Yang; Sharpe, Sarah S.; Wiesenfeld, Kurt; Goldman, Daniel I.

    2013-01-01

    Undulatory locomotion, a gait in which thrust is produced in the opposite direction of a traveling wave of body bending, is a common mode of propulsion used by animals in fluids, on land, and even within sand. As such, it has been an excellent system for discovery of neuromechanical principles of movement. In nearly all animals studied, the wave of muscle activation progresses faster than the wave of body bending, leading to an advancing phase of activation relative to the curvature toward the tail. This is referred to as “neuromechanical phase lags” (NPL). Several multiparameter neuromechanical models have reproduced this phenomenon, but due to model complexity, the origin of the NPL has proved difficult to identify. Here, we use perhaps the simplest model of undulatory swimming to predict the NPL accurately during sand-swimming by the sandfish lizard, with no fitting parameters. The sinusoidal wave used in sandfish locomotion, the friction-dominated and noninertial granular resistive force environment, and the simplicity of the model allow detailed analysis, and reveal the fundamental mechanism responsible for the phenomenon: the combination of synchronized torques from distant points on the body and local traveling torques. This general mechanism should help explain the NPL in organisms in other environments; we therefore propose that sand-swimming could be an excellent system with which to generate and test other neuromechanical models of movement quantitatively. Such a system can also provide guidance for the design and control of robotic undulatory locomotors in complex environments. PMID:23733931

  14. Emergence of the advancing neuromechanical phase in a resistive force dominated medium.

    PubMed

    Ding, Yang; Sharpe, Sarah S; Wiesenfeld, Kurt; Goldman, Daniel I

    2013-06-18

    Undulatory locomotion, a gait in which thrust is produced in the opposite direction of a traveling wave of body bending, is a common mode of propulsion used by animals in fluids, on land, and even within sand. As such, it has been an excellent system for discovery of neuromechanical principles of movement. In nearly all animals studied, the wave of muscle activation progresses faster than the wave of body bending, leading to an advancing phase of activation relative to the curvature toward the tail. This is referred to as "neuromechanical phase lags" (NPL). Several multiparameter neuromechanical models have reproduced this phenomenon, but due to model complexity, the origin of the NPL has proved difficult to identify. Here, we use perhaps the simplest model of undulatory swimming to predict the NPL accurately during sand-swimming by the sandfish lizard, with no fitting parameters. The sinusoidal wave used in sandfish locomotion, the friction-dominated and noninertial granular resistive force environment, and the simplicity of the model allow detailed analysis, and reveal the fundamental mechanism responsible for the phenomenon: the combination of synchronized torques from distant points on the body and local traveling torques. This general mechanism should help explain the NPL in organisms in other environments; we therefore propose that sand-swimming could be an excellent system with which to generate and test other neuromechanical models of movement quantitatively. Such a system can also provide guidance for the design and control of robotic undulatory locomotors in complex environments.

  15. Double minute chromosomes in mouse methotrexate-resistant cells studied by atomic force microscopy

    SciTech Connect

    Deng Xinyu; Zhang Liangyu; Zhang Yu; Yan Yongda; Xu Zongwei; Dong Shen; Fu Songbin . E-mail: fusb@ems.hrbmu.edu.cn

    2006-08-11

    Double minute chromosomes (DMs) are acentric, autonomously replicating extra-chromosomes and frequently mediate gene amplification in tumor and drug resistant cells. Atomic force microscopy (AFM) is a powerful tool in microbiology. We used AFM to explore the ultrastructure of DMs in mouse fibroblasts 3T3R500. DMs in various phases of cell cycle were also studied in order to elucidate the mechanisms of their duplication and separation. Metaphase spread and induced premature condensed chromosomes (PCCs) were observed under the AFM. DMs were detected to be composed of two compact spheres linked by fibers. The fibers of DMs directly connected with metaphase chromosomes were observed. Many single-minutes and few DMs were detected in G1 PCCs, while more DMs were detected in S PCCs than in G1 PCCs. Besides, all of the DMs in G2 PCCs were coupled. Our present results suggested that DMs might divide into single-minutes during or before G1-phase, followed by duplication of the single-minutes in S-phase. Moreover, we introduced a new powerful tool to study DMs and got some ideal results.

  16. An evaluation of underbody forced-air and resistive heating during hypothermic, on-pump cardiac surgery.

    PubMed

    Engelen, S; Himpe, D; Borms, S; Berghmans, J; Van Cauwelaert, P; Dalton, J E; Sessler, D I

    2011-02-01

    We conducted a randomised controlled trial to compare the efficacy of underbody forced-air warming (Arizant Healthcare Inc, Eden Prairie, MN, USA) with an underbody resistive heating mattress (Inditherm Patient Warming System, Rotherham, UK) and passive insulation in 129 patients having hypothermic cardiac surgery with cardiopulmonary bypass. Patients were separated from cardiopulmonary bypass at a core temperature of 35 °C and external warming continued until the end of surgery. Before cardiopulmonary bypass, the temperature-vs-time slopes were significantly greater in both active warming groups than in the passive insulation group (p < 0.001 for each). However, the slopes of forced-air and resistive warming did not differ (p = 0.55). After cardiopulmonary bypass, the rate of rewarming was significantly greater with forced-air than with resistive warming or passive insulation (p < 0.001 for each), while resistive warming did not differ from passive insulation (p = 0.14). However, absolute temperature differences among the groups were small.

  17. Transition of torque pattern in undulatory locomotion due to wave number variation in resistive force dominated media

    NASA Astrophysics Data System (ADS)

    Ding, Yang; Ming, Tingyu

    2016-11-01

    In undulatory locomotion, torque (bending moment) is required along the body to overcome the external forces from environments and bend the body. Previous observations on animals using less than two wavelengths on the body showed such torque has a single traveling wave pattern. Using resistive force theory model and considering the torque generated by external force in a resistive force dominated media, we found that as the wave number (number of wavelengths on the locomotor's body) increases from 0.5 to 1.8, the speed of the traveling wave of torque decreases. When the wave number increases to 2 and greater, the torque pattern transits from a single traveling wave to a two traveling waves and then a complex pattern that consists two wave-like patterns. By analyzing the force distribution and its contribution to the torque, we explain the speed decrease of the torque wave and the pattern transition. This research is partially supported by the Recruitment Program of Global Young Experts (China).

  18. Magnetic force microscopy of colossal magneto-resistive materials and superconductors

    NASA Astrophysics Data System (ADS)

    Lu, Qingyou

    Using a home-built low temperature piezo-driven magnetic force microscope (LT-PD-MFM), we have studied the magnetic domain behaviors in colossal magneto-resistive (CMR) thin films, the vortex behavior in high TC superconducting (HTCS) thin films as well as the localized penetration depth in a Yttrium(1)Barium(2)Copper(3)Oxygen(7) single crystal. We have obtained MFM images of domains in CMR films for temperatures from close to TC to far below TC. Domains behave differently for these two temperature zones. Well below TC, neighboring domains exhibit strong interdomain coupling. External magnetic fields can split domains more easily than rearrange them. As temperature increases, domain interactions become weaker with a reduced magnetization, and are subject to moving, splitting or merging. They are still traceable in the presence of a sample scratch. As temperature drops from TC, domains increase in magnetization. The weak interdomain interactions and high fluctuations make domain tracing impossible if there are no topographic defects. Sample scratches tend to pin domains for T ˜ TC. Current flow in CMR films can split domains. This splitting can be both reversible and irreversible when current is turned on and off. Lattice mismatch between a CMR film and a substrate leads to a stress that results in smaller domains. The magnetization of these smaller domains does not cancel out, resulting in "large-scale" domains if detected from a longer distance from the sample. Images of superconducting vortices in BSSCO films show that they grow with temperature, which is compared with the theory. The theory fits our experimental data well. We also measured the gradient of the levitation force between a magnetic tip and a superconducting single crystal as a function of the tip-sample distance. A series of these measurements were performed at different temperatures. By comparing these data with the theory in which the penetration depth lambda and the TC are parameters to be

  19. Intraspinal microstimulation preferentially recruits fatigue-resistant muscle fibres and generates gradual force in rat

    PubMed Central

    Bamford, JA; Putman, CT; Mushahwar, VK

    2005-01-01

    Intraspinal microstimulation (ISMS), a novel rehabilitative therapy consisting of stimulation through fine, hair-like microwires targeted at the ventral spinal cord, has been proposed for restoring standing and walking following spinal cord injury. This study compared muscle recruitment characteristics of ISMS with those produced by peripheral nerve cuff stimulation (NCS). Thirty-three minutes of either ISMS or NCS at 1, 20 or 50 s−1 and 1.2 × threshold (T) amplitude depleted glycogen from muscle fibres of vastus lateralis and rectus femoris. ISMS and NCS were also carried out at 20 s−1 and 3.0T. Muscle serial sections were stained for glycogen and for myosin heavy chain (MHC)-based fibre types using a panel of monoclonal antibodies. The results of this study show that ISMS recruited fatigue-resistant (FR) fibres at 2.9, 1.9, 1.7 and 2.5 times their relative MHC content at 1, 20 and 50 s−1 1.2T and 20 s−1 3.0T, respectively. In contrast, NCS recruited FR fibres at 1.2, 1.0, 2.1 and 0.0 times their MHC content at 1, 20 and 50 s−1 1.2T and 20 s−1 3.0T, respectively. The proportion of FR fibres recruited by ISMS and NCS was significantly different in the 20 s−1 3.0T condition (P < 0.0001). We also report that force recruitment curves were 4.9-fold less steep (P < 0.019) for ISMS than NCS. The findings of this study provide evidence for the efficacy of ISMS and further our understanding of muscle recruitment properties of this novel rehabilitative therapy. PMID:16239281

  20. Navy Force Structure: Sustainable Plan and Comprehensive Assessment Needed to Mitigate Long-Term Risks to Ships Assigned to Overseas Homeports

    DTIC Science & Technology

    2015-05-01

    Page iii GAO-15-329 Navy Force Structure Figure 5: Percentage of Time Navy Allocates to Training and Maintenance versus Being...response plan— and interviewed Navy officials to discuss this plan, its purpose, expected benefits, and impact on ships’ time allocated to...27Percentages do not add up to 100 due to rounding. Page 16 GAO-15-329 Navy Force Structure Figure 5: Percentage of Time Navy Allocates to

  1. Random myosin loss along thick-filaments increases myosin attachment time and the proportion of bound myosin heads to mitigate force decline in skeletal muscle

    PubMed Central

    Tanner, Bertrand C.W.; McNabb, Mark; Palmer, Bradley M.; Toth, Michael J.; Miller, Mark S.

    2014-01-01

    Diminished skeletal muscle performance with aging, disuse, and disease may be partially attributed to the loss of myofilament proteins. Several laboratories have found a disproportionate loss of myosin protein content relative to other myofilament proteins, but due to methodological limitations, the structural manifestation of this protein loss is unknown. To investigate how variations in myosin content affect ensemble cross-bridge behavior and force production we simulated muscle contraction in the half-sarcomere as myosin was removed either i) uniformly, from the Z-line end of thick-filaments, or ii) randomly, along the length of thick-filaments. Uniform myosin removal decreased force production, showing a slightly steeper force-to-myosin content relationship than the 1:1 relationship that would be expected from the loss of cross-bridges. Random myosin removal also decreased force production, but this decrease was less than observed with uniform myosin loss, largely due to increased myosin attachment time (ton) and fractional cross-bridge binding with random myosin loss. These findings support our prior observations that prolonged ton may augment force production in single fibers with randomly reduced myosin content from chronic heart failure patients. These simulation also illustrate that the pattern of myosin loss along thick-filaments influences ensemble cross-bridge behavior and maintenance of force throughout the sarcomere. PMID:24486373

  2. Random myosin loss along thick-filaments increases myosin attachment time and the proportion of bound myosin heads to mitigate force decline in skeletal muscle.

    PubMed

    Tanner, Bertrand C W; McNabb, Mark; Palmer, Bradley M; Toth, Michael J; Miller, Mark S

    2014-06-15

    Diminished skeletal muscle performance with aging, disuse, and disease may be partially attributed to the loss of myofilament proteins. Several laboratories have found a disproportionate loss of myosin protein content relative to other myofilament proteins, but due to methodological limitations, the structural manifestation of this protein loss is unknown. To investigate how variations in myosin content affect ensemble cross-bridge behavior and force production we simulated muscle contraction in the half-sarcomere as myosin was removed either (i) uniformly, from the Z-line end of thick-filaments, or (ii) randomly, along the length of thick-filaments. Uniform myosin removal decreased force production, showing a slightly steeper force-to-myosin content relationship than the 1:1 relationship that would be expected from the loss of cross-bridges. Random myosin removal also decreased force production, but this decrease was less than observed with uniform myosin loss, largely due to increased myosin attachment time (ton) and fractional cross-bridge binding with random myosin loss. These findings support our prior observations that prolonged ton may augment force production in single fibers with randomly reduced myosin content from chronic heart failure patients. These simulations also illustrate that the pattern of myosin loss along thick-filaments influences ensemble cross-bridge behavior and maintenance of force throughout the sarcomere. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Effects of Inertial Setting on Power, Force, Work, and Eccentric Overload During Flywheel Resistance Exercise in Women and Men.

    PubMed

    Martinez-Aranda, Luis M; Fernandez-Gonzalo, Rodrigo

    2017-06-01

    Exercise load is a key component in determining end-point adaptations to resistance exercise. Yet, there is no information regarding the use of different inertia (i.e., loads) during isoinertial flywheel resistance exercise, a very popular high-intensity training model. Thus, this study examined power, work, force, and eccentric overload produced during flywheel resistance exercise with different inertial settings in men and women. Twenty-two women (n = 11) and men (n = 11) performed unilateral (in both legs) isolated concentric (CON) and coupled CON and eccentric (ECC) exercise in a flywheel knee extension device employing 6 inertias (0.0125, 0.025, 0.0375, 0.05, 0.075, 0.1 kg·m). Power decreased as higher inertias were used, with men showing greater (p ≤ 0.05) decrements than women (-36 vs. -29% from lowest to highest inertia). In contrast, work increased as higher inertias were employed, independent of sex (p ≤ 0.05; ∼48% from lowest to highest inertia). Women increased CON and ECC mean force (46-55%, respectively) more (p ≤ 0.05) than men (34-50%, respectively) from the lowest to the highest inertia evaluated, although the opposite was found for peak force data (i.e., peak force increased more in men than in women as inertia was increased). Men, but not women, increased ECC overload from inertia 0.0125 to 0.0375 kg·m2. Although estimated stretch-shorting cycle use during flywheel exercise was higher (p ≤ 0.05) in men (6.6%) than women (4.9%), values were greater for both sexes when using low-to-medium inertias. The information gained in this study could help athletes and sport and health professionals to better understand the impact of different inertial settings on skeletal muscle responses to flywheel resistance exercise.

  4. Effects of inertial setting on power, force, work and eccentric overload during flywheel resistance exercise in women and men.

    PubMed

    Martinez-Aranda, Luis Manuel; Fernandez-Gonzalo, Rodrigo

    2016-09-16

    Exercise load is a key component in determining end-point adaptations to resistance exercise. Yet, there is no information regarding the use of different inertia (i.e. loads) during iso-inertial flywheel resistance exercise, a very popular high-intensity training model. Thus, this study examined power, work, force and eccentric-overload produced during flywheel resistance exercise with different inertial settings in men and women. Twenty-two women (n=11) and men (n=11) performed unilateral (in both legs) isolated concentric (CON) and coupled CON and eccentric (ECC) exercise in a flywheel knee extension device employing six inertias (0.0125, 0.025, 0.0375, 0.05, 0.075, 0.1 kg*m). Power decreased as higher inertias were used, with men showing greater (P< 0.05) decrements than women (-36% vs. -29% from lowest to highest inertia). In contrast, work increased as higher inertias were employed, independent of sex (P<0.05; ∼48% from lowest to highest inertia). Women increased CON and ECC mean force (46-55%, respectively) more (P<0.05) than men (34-50%, respectively) from the lowest to the highest inertia evaluated, although the opposite was found for peak force data (i.e. peak force increased more in men than in women as inertia was increased). Men, but not women, increased ECC overload from inertia 0.0125 to 0.0375 kg*m. While estimated stretch-shorting cycle use during flywheel exercise was higher (P<0.05) in men (6.6%) than women (4.9%), values were greater for both sexes when using low to -medium inertias. The information gained in this study could help athletes and sport and health professionals to better understand the impact of different inertial settings on skeletal muscle responses to flywheel resistance exercise.

  5. Proton motive force-driven and ATP-dependent drug extrusion systems in multidrug-resistant Lactococcus lactis.

    PubMed Central

    Bolhuis, H; Molenaar, D; Poelarends, G; van Veen, H W; Poolman, B; Driessen, A J; Konings, W N

    1994-01-01

    Three mutants of Lactococcus lactis subsp. lactis MG1363, termed EthR, DauR, and RhoR, were selected for resistance to high concentrations of ethidium bromide, daunomycin, and rhodamine 6G, respectively. These mutants were found to be cross resistant to a number of structurally and functionally unrelated drugs, among which were typical substrates of the mammalian multidrug transporter (P-glycoprotein) such as daunomycin, quinine, actinomycin D, gramicidin D, and rhodamine 6G. The three multidrug-resistant strains showed an increased rate of energy-dependent ethidium and daunomycin efflux compared with that of the wild-type strain. This suggests that resistance to these toxic compounds is at least partly due to active efflux. Efflux of ethidium from the EthR strain could occur against a 37-fold inwardly directed concentration gradient. In all strains, ethidium efflux was inhibited by reserpine, a well-known inhibitor of P-glycoprotein. Ionophores which selectively dissipate the membrane potential or the pH gradient across the membrane inhibited ethidium and daunomycin efflux in the wild-type strain, corresponding with a proton motive force-driven efflux system. The ethidium efflux system in the EthR strain, on the other hand, was inhibited by ortho-vanadate and not upon dissipation of the proton motive force, which suggests the involvement of ATP in the energization of transport. The partial inhibition of ethidium efflux by ortho-vanadate and nigericin in the DauR and RhoR strains suggest that a proton motive force-dependent and an ATP-dependent system are expressed simultaneously. This is the first report of an ATP-dependent transport system in prokaryotes which confers multidrug resistance to the organism. PMID:7961458

  6. Changes in the Force-Velocity Mechanical Profile After Short Resistance Training Programmes Differing in Set Configurations.

    PubMed

    Iglesias-Soler, Eliseo; Fernández-Del-Olmo, Miguel; Mayo, Xián; Fariñas, Juan; Río-Rodríguez, Dan; Carballeira, Eduardo; Carnero, Elvis A; Standley, Robert A; Giráldez-García, Manuel A; Dopico-Calvo, Xurxo; Tuimil, Jose Luis

    2016-12-05

    The main aim of this study was to analyse the effect of resistance training programs differing in set configuration on mechanical force-velocity profiles. Thirteen participants performed ten unilateral knee extension training sessions over 5 weeks. Each limb was randomised to one of the following set configurations: traditional (4 sets of 8 repetitions at maximum intended velocity, 10RM load, 3-min pause between sets), and inter-repetition rest (32 maximum intended velocity repetitions, 10RM load, 17.4 s of rest between each repetition). Velocity of each repetition was recorded throughout the programme. Before, and after training, individual linear force-velocities were calculated, and the following parameters were obtained: force, and velocity axis intercept, slope, and estimated maximum power. Mean velocity was higher throughout the programme for inter-repetition rest configuration (0.54±0.01 vs. 0.48±0.01 m.s(-1) for inter-repetition rest, and traditional configuration respectively; main effect of set configuration: p<0.001). There was a significant increase in force and velocity intercepts, but a steeper negative slope after both training protocols (main effect of time: p<0.001 for every variable). Differences in resistance training velocity did not affect the adaptations. Our results suggest that in a short-term programme maximum intended rather than actual velocity is a key factor to modulate strength adaptations.

  7. Enhancing the examiner's resisting force improves the validity of manual muscle strength measurements: application to knee extensors and flexors.

    PubMed

    Lu, Tung-Wu; Chien, Hui-Lien; Chang, Ling-Ying; Hsu, Horng-Chaung

    2012-09-01

    The purposes of this study were to test whether an examiner's strength may affect the validity of the knee muscle strength measurements using a hand-held dynamometer (HHD) and whether enhancing the forces applied by an examiner using a resistance-enhanced dynamometer (RED) would improve measurement validity. Twenty-five young male volunteers (mean [±SD] age: 22.5 ± 1.7 years) without a history of injury to the test limb and 6 male and 6 female experienced examiners participated in this study. Maximum resisting forces of the knee flexors and extensors were measured using RED, HHD, and a dynamometer (Kin-Com). For all testing conditions, poor to moderate associations were found between the HHD and Kin-Com, whereas there was a good to excellent relationship between RED and Kin-Com. The systematic variations between RED and Kin-Com were also smaller than those between HHD and Kin-Com. The force values measured by RED were very close to those measured by Kin-Com. An examiner's strength affects the validity of the measurements using HHD. Enhancing the forces applied by the examiner to the tested segment using RED appeared to improve the validity of muscle strength measurements.

  8. A Review on Resistive Switching in High-k Dielectrics: A Nanoscale Point of View Using Conductive Atomic Force Microscope

    PubMed Central

    Lanza, Mario

    2014-01-01

    Metal-Insulator-Metal (MIM) structures have raised as the most promising configuration for next generation information storage, leading to great performance and fabrication-friendly Resistive Random Access Memories (RRAM). In these cells, the memory concept is no more based on the charge storage, but on tuning the electrical resistance of the insulating layer by applying electrical stresses to reach a high resistive state (HRS or “0”) and a low resistive state (LRS or “1”), which makes the memory point. Some high-k dielectrics show this unusual property and in the last years high-k based RRAM have been extensively analyzed, especially at the device level. However, as resistance switching (in the most promising cells) is a local phenomenon that takes place in areas of ~100 nm2, the use of characterization tools with high lateral spatial resolution is necessary. In this paper the status of resistive switching in high-k materials is reviewed from a nanoscale point of view by means of conductive atomic force microscope analyses. PMID:28788561

  9. Ensuring U.S. Air Force Operations During Cyber Attacks Against Combat Support Systems: Guidance for Where to Focus Mitigation Efforts

    DTIC Science & Technology

    2015-01-01

    Cyberdeterrence and Cyberwar , Santa Monica, Calif.: RAND Corporation, MG-877-AF, 2009. 3 identified in the Component Numbered Air Force (C-NAF...Albuquerque, N.M.: Sandia National Laboratories, SAND98-8667, October 1998. Libicki, Martin C., Cyberdeterrence and Cyberwar , Santa Monica

  10. Disruption Mitigation Studies in DIII--D

    NASA Astrophysics Data System (ADS)

    Taylor, P. L.

    1998-11-01

    Critical to the viability of the tokamak concept along with the operation and survivability of future devices is the development of techniques to terminate the discharge safely and mitigate the destructive effects of disruptions: high thermal and electromagnetic loads as well as intense high energy runaway electron beams. A series of dedicated disruption experiments on DIII--D have provided further data on the discharge behavior, thermal loads, halo currents, and runaway electrons and have evaluated techniques to mitigate the disruptions while minimizing runaway electron production. Non-axisymmetric halo currents occur with currents up to 30% of the plasma current and with toroidal peaking factors of 2 at the time of peak halo current. Large heat fluxes are also measured with up to 100% of the pre-disruption thermal energy deposited on the divertor floor. Fundamental questions on the halo current generation, scaling, and mitigation are being addressed by comparisons of DIII--D plasmas during disruptions with the DINA time-dependent resistive MHD code and with semi-analytic halo current evolution models. Experiments injecting cryogenic impurity ``killer'' pellets of neon, argon, and methane have successfully mitigated these disruption effects; reducing the halo currents by 30%--50%, lowering the halo current asymmetry to near unity, reducing the vertical force on the vessel, and enhancing the power loss through the radiation channel to ~90%. Often runaway electrons are generated following the pellet injection and results of recent experiments using pre-emptive ``killer'' pellets help benchmark theoretical models of the pellet ablation and plasma energy loss (KPRAD and TSC codes), and of the runaway electron generation (CQL3D Fokker-Planck code). Use of the models has led to two new runaway generation mechanisms; both a modification of the standard Dreicer process and arising out of instability induced transport or time dependent effects. Experiments with a massive

  11. Comparison Between the Effects of Combining Elastic and Free-Weight Resistance and Free-Weight Resistance on Force and Power Production.

    PubMed

    Paditsaeree, Kampanart; Intiraporn, Chaninchai; Lawsirirat, Chaipat

    2016-10-01

    Paditsaeree, K, Intiraporn, C, and Lawsirirat, C. Comparison between the effects of combining elastic and free-weight resistance and free-weight resistance on force and power production. J Strength Cond Res 30(10): 2713-2722, 2016-Elastic tubing attached to a barbell has been reported to enhance strength and power to a greater extent as compared with conventional barbells. The aim of this study was to investigate the effect of the additional elastic tubing to a barbell during a clean pull on peak power (PP), peak velocity (PV), and peak force (PF). Six competitive female weightlifters (mean age, 16.7 ± 2.1 years) performed 3 sets of 3 repetitions of the clean pull at 90% of 1 repetition maximum (1RM). Testing was conducted on 3 separate days: day 1 without elastic tubing (no tubing [NT]) and the other 2 days with 2 elastic tubing loading conditions (T10 and T20), in random order. No tubing represents a condition where all resistance was acquired from the barbell (90% of 1RM). T10 and T20 represent conditions of combining elastic tubing at 10 and 20% of the subjects' 90% 1RM with a barbell (90% of 1RM). One-way repeated-measures analysis of variance was used to assess loading conditions on PP, PV, and PF. The results showed that there was a significant increase in all variables-PP, PF, and PV-between T10 and NT and between T20 and NT (p ≤ 0.05). The results revealed that adding a 10% increment to 90% of 1RM seems to be the optimal training condition for increasing power, force, and velocity during the clean pull.

  12. 32 CFR 989.22 - Mitigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.22 Mitigation. (a) When preparing EIAP documents, indicate... should include the cost of mitigation as a line item in the budget for a proposed project. The...

  13. Growth and cell-division in extensive (XDR) and extremely drug resistant (XXDR) tuberculosis strains: transmission and atomic force observation.

    PubMed

    Farnia, Parissa; Mohammad, Reza Masjedi; Merza, Muayad Aghali; Tabarsi, Payam; Zhavnerko, Gennadii Konstantinovich; Ibrahim, Tengku Azmi; Kuan, Ho Oi; Ghanavei, Jalladein; Farnia, Poopak; Ranjbar, Reza; Poleschuyk, Nikolai Nikolaevich; Titov, Leonid Petrovich; Owlia, Parviz; Kazampour, Mehadi; Setareh, Mohammad; Sheikolslami, Muaryam; Migliori, Giovanni Battista; Velayati, Ali Akbar

    2010-09-30

    The ultra-structure of Mycobacterium tuberculosis (MTB) was examined by transmission electronic (TEM)) and atomic force microscopy (AFM). The study was performed to describe the morphology of susceptible, multidrug-resistant (MDR), extensively drug-resistant (XDR) and extremely drug-resistant tuberculosis isolates (XXDR-TB) during their exponential growth phase. Four types of cell division were observed and described. While three of them (symmetrical, asymmetrical and branching type) occurred in all isolates studied, the fourth one (adapted type) was seen only in XDR and XXDR-TB bacilli. In the fourth type of cell division, a rod shaped mother cell produced a small round shape bacillus (0.3-0.5 μm). These round cells were different from buds or polar division, but similar to terminal endospores without showing the typing heat resistance. Based on the present observation, we suggest that XDR-and XXDR-TB bacilli accommodate changes helping them to overcome the hostile environment. Viewed under AFM, the other frequently detected shapes in MTB isolates were oval, V, Y and multi-branching filaments. These shape variation confirmed pleomorphic phenomena in MTB populations and the specific features of pan-resistant strains.

  14. Safety and efficacy of resistive polymer versus forced air warming in total joint surgery.

    PubMed

    Sandoval, Melanie F; Mongan, Paul D; Dayton, Michael R; Hogan, Craig A

    2017-01-01

    Forced-air warming is used as a mechanism to prevent hypothermia and adverse outcomes associated with hypothermia among patients undergoing surgery. Patient safety in healthcare includes the use of devices and technology that minimize potential adverse events to patients. The present study sought to compare the capabilities of patient warming between two different devices that use different mechanisms of warming: forced-air warming and non-air warming. One hundred twenty patients undergoing total hip or total knee arthroplasty received patient warming via a forced warming device or non-air warming fabric conductive material. The project was part of a quality improvement initiative to identify warming devices effective in maintaining normothermic patient core temperatures during orthopedic surgery. Forced-air warming and non-air warming achieved similar results in maintaining the core temperature of patients undergoing total knee or hip arthroplasty. No adverse events were reported in either group. Operating room staff observed that the non-air warming device was less noisy and appreciated the disposable covers that could be changed after each surgical case. These findings demonstrate that hypothermia is achieved by both forced-air and non-forced air warming devices among total knee and hip arthroplasty patients. The potential for airflow disruption is present with the forced-air warming device and does not exist with the non-forced air device. The disruption of laminar airflow may be associated with surgical site infections. The disposable covers used to protect the device and patient have potential implications for surgical site infection. Quality improvement efforts aimed to enhance patient safety should include the implementation of healthcare equipment with the least known or suspected risk.

  15. Design of new schools and other large buildings which are radon resistant and easy to mitigate. Report for September 1990-August 1991

    SciTech Connect

    Craig, A.B.; Leovic, K.W.; Harris, D.B.

    1992-01-01

    The paper discusses the recent incorporation of radon mitigation design recommendations in the construction of a hospital in Johnson City, TN. The recommendations resulted in the mitigation of a 5,500 square meter building with only one suction point at an incremental cost of $1.03 per square meter. Extrapolation of the pressure field extension (PFE) measurements indicates that a much larger building could have been mitigated with the system used. A search is underway for larger buildings to be built in radon prone areas of the U.S. in order to determine the effectiveness of the mitigation system in reducing radon in even larger buildings. As a prelude to the preparation of a new construction technical guidance document for schools, architectural drawings of all schools research by EPA, to date, were carefully studied to determine which building characteristics affect radon entry and ease of mitigation. Results of the study were presented at an international symposium on radon in Philadelphia, PA, in April 1991.

  16. The Air Force Weapons Laboratory Skid Resistance Research Program, 1969- 1974

    DTIC Science & Technology

    1975-05-01

    EVALUATION SYSTEM 8 1. General 8 2. Test Equipment and Procedures 8 3. Equipment 8 4. Testing Procedure 10 5. Test Results 12 6. Friction Recovery With Time ...prompted by the increased landing speeds of jet aircraft, to- gether with the increased number of wet-weather landings permitted by improved flight ...RESISTANCE EVALUATION SYSTEM During the time period 1970 - 1973, an active research program in skid resistance was conducted by the Civil Engineering

  17. Particle Hardening in Creep-Resistant Mg-Alloy MRI 230D Probed by Nanoindenting Atomic Force Microscopy

    NASA Astrophysics Data System (ADS)

    Backes, Björn; Durst, Karsten; Amberger, Dorothea; Göken, Mathias

    2009-02-01

    Two different Mg alloys, AZ91 and MRI 230D, have been investigated with the objective to understand the differences in high-temperature deformation behavior. AZ91 is known for its rather poor creep resistance; in contrast to this, MRI 230D is known to have a rather high resistance against plastic deformation at elevated temperatures. The microstructure and mechanical properties of as-cast and crept specimens of two Mg alloys (AZ91 and MRI 230D) were characterized by nanoindenting atomic force microscopy (NI-AFM). In the cell interior, a significant higher hardness was found for MRI 230D in comparison to AZ91. Precipitates with an average size of about 50 nm found in the cell interior of MRI 230D after creep deformation are discussed as the major hardening component.

  18. Effect of brief daily resistance training on rapid force development in painful neck and shoulder muscles: randomized controlled trial

    PubMed Central

    Jay, Kenneth; schraefel, mc; Andersen, Christoffer H; Ebbesen, Frederik S; Christiansen, David H; Skotte, Jørgen; Zebis, Mette K; Andersen, Lars L

    2013-01-01

    Objective: To determine the effect of small daily amounts of progressive resistance training on rapid force development of painful neck/shoulder muscles. Methods: 198 generally healthy adults with frequent neck/shoulder muscle pain (mean: age 43·1 years, computer use 93% of work time, 88% women, duration of pain 186 day during the previous year) were randomly allocated to 2- or 12 min of daily progressive resistance training with elastic tubing or to a control group receiving weekly information on general health. A blinded assessor took measures at baseline and at 10-week follow-up; participants performed maximal voluntary contractions at a static 90-degree shoulder joint angle. Rapid force development was determined as the rate of torque development and maximal muscle strength was determined as the peak torque. Results: Compared with the control group, rate of torque development increased 31·0 Nm s−1 [95% confidence interval: (1·33–11·80)] in the 2-min group and 33·2 Nm s−1 (1·66–12·33) in the 12-min group from baseline to 10-week follow-up, corresponding to an increase of 16·0% and 18·2% for the two groups, respectively. The increase was significantly different compared to controls (P<0·05) for both training groups. Maximal muscle strength increased only ∼5–6% [mean and 95% confidence interval for 2- and 12-min groups to control, respectively: 2·5 Nm (0·05–0·73) and 2·2 Nm (0·01–0·70)]. No significant differences between the 2- and 12-min groups were evident. A weak but significant relationship existed between changes in rapid force development and pain (r = 0·27, P<0·01), but not between changes in maximal muscle strength and pain. Conclusion: Small daily amounts of progressive resistance training in adults with frequent neck/shoulder pain increases rapid force development and, to a less extent, maximal force capacity. PMID:23758661

  19. Wide range local resistance imaging on fragile materials by conducting probe atomic force microscopy in intermittent contact mode

    SciTech Connect

    Vecchiola, Aymeric; Chrétien, Pascal; Schneegans, Olivier; Mencaraglia, Denis; Houzé, Frédéric; Delprat, Sophie; Bouzehouane, Karim; Seneor, Pierre; Mattana, Richard; Tatay, Sergio; Geffroy, Bernard; and others

    2016-06-13

    An imaging technique associating a slowly intermittent contact mode of atomic force microscopy (AFM) with a home-made multi-purpose resistance sensing device is presented. It aims at extending the widespread resistance measurements classically operated in contact mode AFM to broaden their application fields to soft materials (molecular electronics, biology) and fragile or weakly anchored nano-objects, for which nanoscale electrical characterization is highly demanded and often proves to be a challenging task in contact mode. Compared with the state of the art concerning less aggressive solutions for AFM electrical imaging, our technique brings a significantly wider range of resistance measurement (over 10 decades) without any manual switching, which is a major advantage for the characterization of materials with large on-sample resistance variations. After describing the basics of the set-up, we report on preliminary investigations focused on academic samples of self-assembled monolayers with various thicknesses as a demonstrator of the imaging capabilities of our instrument, from qualitative and semi-quantitative viewpoints. Then two application examples are presented, regarding an organic photovoltaic thin film and an array of individual vertical carbon nanotubes. Both attest the relevance of the technique for the control and optimization of technological processes.

  20. Wide range local resistance imaging on fragile materials by conducting probe atomic force microscopy in intermittent contact mode

    NASA Astrophysics Data System (ADS)

    Vecchiola, Aymeric; Chrétien, Pascal; Delprat, Sophie; Bouzehouane, Karim; Schneegans, Olivier; Seneor, Pierre; Mattana, Richard; Tatay, Sergio; Geffroy, Bernard; Bonnassieux, Yvan; Mencaraglia, Denis; Houzé, Frédéric

    2016-06-01

    An imaging technique associating a slowly intermittent contact mode of atomic force microscopy (AFM) with a home-made multi-purpose resistance sensing device is presented. It aims at extending the widespread resistance measurements classically operated in contact mode AFM to broaden their application fields to soft materials (molecular electronics, biology) and fragile or weakly anchored nano-objects, for which nanoscale electrical characterization is highly demanded and often proves to be a challenging task in contact mode. Compared with the state of the art concerning less aggressive solutions for AFM electrical imaging, our technique brings a significantly wider range of resistance measurement (over 10 decades) without any manual switching, which is a major advantage for the characterization of materials with large on-sample resistance variations. After describing the basics of the set-up, we report on preliminary investigations focused on academic samples of self-assembled monolayers with various thicknesses as a demonstrator of the imaging capabilities of our instrument, from qualitative and semi-quantitative viewpoints. Then two application examples are presented, regarding an organic photovoltaic thin film and an array of individual vertical carbon nanotubes. Both attest the relevance of the technique for the control and optimization of technological processes.

  1. Forcing attacks of western pine beetles to test resistance of pines

    Treesearch

    Richard H. Smith

    1967-01-01

    Success--defined as oviposition or tree-killing--was obtained by attracting western pine beetles to groups of pines with natural attractants and by en-massed forced attacks on individual trees combined with either physical or biological stress. Preliminary results show considerable agreement with laboratory tests of vapor toxicity.

  2. Mouse forepaw lumbrical muscles are resistant to age-related declines in force production.

    PubMed

    Russell, Katelyn A; Ng, Rainer; Faulkner, John A; Claflin, Dennis R; Mendias, Christopher L

    2015-05-01

    A progressive loss of skeletal muscle mass and force generating capacity occurs with aging. Mice are commonly used in the study of aging-associated changes in muscle size and strength, with most models of aging demonstrating 15-35% reductions in muscle mass, cross-sectional area (CSA), maximum isometric force production (Po) and specific force (sPo), which is Po/CSA. The lumbrical muscle of the mouse forepaw is exceptionally small, with corresponding short diffusion distances that make it ideal for in vitro pharmacological studies and measurements of contractile properties. However, the aging-associated changes in lumbrical function have not previously been reported. To address this, we tested the hypothesis that compared to adult (12month old) mice, the forepaw lumbrical muscles of old (30month old) mice exhibit aging-related declines in size and force production similar to those observed in larger limb muscles. We found that the forepaw lumbricals were composed exclusively of fibers with type II myosin heavy chain isoforms, and that the muscles accumulated connective tissue with aging. There were no differences in the number of fibers per whole-muscle cross-section or in muscle fiber CSA. The whole muscle CSA in old mice was increased by 17%, but the total CSA of all muscle fibers in a whole-muscle cross-section was not different. No difference in Po was observed, and while sPo normalized to total muscle CSA was decreased in old mice by 22%, normalizing Po by the total muscle fiber CSA resulted in no difference in sPo. Combined, these results indicate that forepaw lumbrical muscles from 30month old mice are largely protected from the aging-associated declines in size and force production that are typically observed in larger limb muscles. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Mouse Forepaw Lumbrical Muscles are Resistant to Age-Related Declines in Force Production

    PubMed Central

    Russell, Katelyn A; Ng, Rainer; Faulkner, John A; Claflin, Dennis R; Mendias, Christopher L

    2015-01-01

    A progressive loss of skeletal muscle mass and force generating capacity occurs with aging. Mice are commonly used in the study of aging-associated changes in muscle size and strength, with most models of aging demonstrating 15-35% reductions in muscle mass, cross-sectional area (CSA), maximum isometric force production (Po) and specific force (sPo), which is Po/CSA. The lumbrical muscle of the mouse forepaw is exceptionally small, with corresponding short diffusion distances that make it ideal for in vitro pharmacological studies and measurements of contractile properties. However, the aging-associated changes in lumbrical function have not previously been reported. To address this, we tested the hypothesis that compared to adult (12 month old) mice, the forepaw lumbrical muscles of old (30 month old) mice exhibit aging-related declines in size and force production similar to those observed in larger limb muscles. We found that the forepaw lumbricals were composed exclusively of fibers with type II myosin heavy chain isoforms, and that the muscles accumulated connective tissue with aging. There were no differences in the number of fibers per whole-muscle cross-section or in muscle fiber CSA. The whole muscle CSA in old mice was increased by 17%, but the total CSA of all muscle fibers in a whole-muscle cross-section was not different. No difference in Po was observed, and while sPo normalized to total muscle CSA was decreased in old mice by 22%, normalizing Po by the total muscle fiber CSA resulted in no difference in sPo. Combined, these results indicate that forepaw lumbrical muscles from 30 month old mice are largely protected from the aging-associated declines in size and force production that are typically observed in larger limb muscles. PMID:25762422

  4. Acaricide resistance and strategies to mitigate economic impact of the southern cattle fever tick (Rhipicephalus microplus) on livestock production systems in the Americas

    USDA-ARS?s Scientific Manuscript database

    BACKGROUND: The southern cattle fever tick (SCFT), Rhipicephalus microplus, is considered the most economically important external parasite of livestock worldwide. SCFT populations resistant to acaricides complicate efforts to enhance the productivity of livestock. Here, acaricide resistance is summ...

  5. Efficacy of a trunk orthosis with joints providing resistive force on low back load during level walking in elderly persons

    PubMed Central

    Katsuhira, Junji; Matsudaira, Ko; Oka, Hiroyuki; Iijima, Shinno; Ito, Akihiro; Yasui, Tadashi; Yozu, Arito

    2016-01-01

    Purpose The effects of lumbosacral and spinal orthoses on low back pain and gait are not exactly clear. We previously developed a trunk orthosis with joints providing resistive force on low back load to decrease such load, and confirmed its positive effects during level walking in healthy young adults. Therefore, we aimed to determine the efficacy of this trunk orthosis during level walking in healthy elderly subjects. Methods Fifteen community-dwelling elderly subjects performed level walking at a self-selected speed without an orthosis, with our orthosis, and with a lumbosacral orthosis. Kinematic and kinetic data were recorded using a three-dimensional motion analysis system, and erector spinae activity was recorded by electromyography. Results When comparing the three conditions, our orthosis showed the following effects: it decreased the peak extension moment, increased the peak flexion moment, decreased the lateral bending angle, increased the peak thoracic extension angle, and had significantly lower erector spinae activity and significantly larger peak pelvic forward tilt angles. Conclusion Our orthosis with joints providing resistive force decreased low back load and modified trunk and pelvis alignments during level walking in healthy elderly people. PMID:27877028

  6. Explosive Resistance Training Increases Rate of Force Development in Ankle Dorsiflexors and Gait Function in Adults With Cerebral Palsy.

    PubMed

    Kirk, Henrik; Geertsen, Svend S; Lorentzen, Jakob; Krarup, Kasper B; Bandholm, Thomas; Nielsen, Jens B

    2016-10-01

    Kirk, H, Geertsen, SS, Lorentzen, J, Krarup, KB, Bandholm, T, and Nielsen, JB. Explosive resistance training increases rate of force development in ankle dorsiflexors and gait function in adults with cerebral palsy. J Strength Cond Res 30(10): 2749-2760, 2016-Alterations in passive elastic properties of muscles and reduced ability to quickly generate muscle force contribute to impaired gait function in adults with cerebral palsy (CP). In this study, we investigated whether 12 weeks of explosive and progressive heavy-resistance training (PRT) increases rate of force development of ankle dorsiflexors (RFDdf), improves gait function, and affects passive ankle joint stiffness in adults with CP. Thirty-five adults (age: 36.5; range: 18-59 years) with CP were nonrandomly assigned to a PRT or nontraining control (CON) group in this explorative trial. The PRT group trained ankle dorsiflexion, plantarflexion, leg press, hamstring curls, abdominal curls, and back extension 3 days per week for 12 weeks, with 3 sets per exercise and progressing during the training period from 12 to 6 repetition maximums. RFDdf, 3-dimensional gait analysis, functional performance, and ankle joint passive and reflex-mediated muscle stiffness were evaluated before and after. RFDdf increased significantly after PRT compared to CON. PRT also caused a significant increase in toe lift late in swing and a significantly more dorsiflexed ankle joint at ground contact and during stance. The increased toe-lift amplitude was correlated to the increased RFDdf (r = 0.73). No other between-group differences were observed. These findings suggest that explosive PRT may increase RFDdf and facilitate larger range of movement in the ankle joint during gait. Explosive PRT should be tested in clinical practice as part of a long-term training program for adults with CP.

  7. Use of Grasp Force Focus Positioning to Enhance the Torque Resistance Capability of Robotic Grasps

    DTIC Science & Technology

    1990-12-13

    Constraints on Total Contact Forces .. .. .. ... ... ..... 2- 8 iii Page 2.8 The Constraint Map .. .. .. .. .... ... ... ... ..... 2-10 2.9 Required...Contact Point. .. .. .. .. ... .... 3-5 3.2.2 Sign of z: .. .. .. .. .. .... .... .... ....... 3- 8 3.2.3 Choice of Grasp and Uniqueness...3- 8 IV. Results and Discussion. .. .. .... ... ... ... ... ... ...... 4-1 4.1 Symmetric Fingertip Grasps. .. .. ... ... ... ........ 4-1 4.1.1

  8. Similar changes in muscle fiber phenotype with differentiated consequences for rate of force development: endurance versus resistance training.

    PubMed

    Farup, Jean; Sørensen, Henrik; Kjølhede, Tue

    2014-04-01

    Resistance training has been shown to positively affect the rate of force development (RFD) whereas there is currently no data on the effect of endurance training on RFD. Subjects completed ten weeks of either resistance training (RT, n=7) or endurance cycling (END, n=7). Pre and post measurements included biopsies obtained from m. vastus lateralis to quantify fiber phenotype and fiber area and isokinetic dynamometer tests to quantify maximal torque (Nm) and RFD (Nm/s) at 0-30, 0-50, 0-100 and 0-200ms during maximal isometric contraction for both knee extensors and flexors. Both groups increased the area percentage of type IIa fibers (p<.01) and decreased the area percentage of type IIx fibers (p=.05), whereas only RT increased fiber size (p<.05). RT significantly increased eccentric, concentric and isometric strength for both knee extensors and flexors, whereas END did not. RT increased 200ms RFD (p<.01) in knee flexor RFD and a tendency towards an increase at 100ms (p<.1), whereas tendencies towards decreases were observed for the END group at 30, 50 and 100ms (p<.1), resulting in RT having a higher RFD than END at post (p<.01). In conclusion, resistance training may be very important for maintaining RFD, whereas endurance training may negatively impact RFD.

  9. Line-pattern collapse mitigation status for EUV at 32nm HP and below

    NASA Astrophysics Data System (ADS)

    Carcasi, Michael; Bassett, Derek; Printz, Wallace; Kawakami, Shinichiro; Miyata, Yuichiro

    2012-03-01

    Line pattern collapse (LPC) becomes a critical concern as integrated circuit fabrication continues to advance towards the 22 nm node and below. Tokyo Electron Limited (TEL) has been investigating LPC mitigation methods for many years [1]. These mitigation methods include surfactant rinses to help reduce surface tension and Laplace pressures forces that accompany traditional DIW rinses. However, the ability to explore LPC mitigation techniques at EUV dimensions is experimentally limited by the cost and availability of EUV exposures. With this in mind, TEL has adopted a combined experimental and simulation approach to further explore LPC mitigation methods. Several analytical models have been proposed [2, 3, 4] for a LPC simulation approach. However, the analytical models based on Euler beam theory are limited in the complexity of profile and material assumptions. Euler beam based models are also now questionable because they are outside the beam theory's intended aspect ratio regime [5]. The authors explore the use of finite element models in addition to Euler beam theory based models to understand resist collapse under typical EUV patterning conditions. The versatility of current finite element techniques allows for exploration of resist material property effects, profile and geometry effects, surface versus bulk modulus effects, and rinse and surfactant rinse effects. This paper will discuss pattern-collapse trends and offers critical learning from this simulation approach combined with experimental results from an EUV exposure system and TEL CLEAN TRACK ACTTM 12 platform, utilizing state of the art collapse mitigation methods.

  10. Gas powered fluid gun with recoil mitigation

    DOEpatents

    Grubelich, Mark C.; Yonas, Gerold

    2017-01-03

    A gas powered fluid gun for propelling a stream or slug of a fluid at high velocity toward a target. Recoil mitigation is provided by a cavitating venturi that reduces or eliminates the associated recoil forces, with minimal or no backwash. By launching a quantity of water in the opposite direction, net momentum forces are reduced or eliminated.

  11. Current-induced forces: a new mechanism to induce negative differential resistance and current-switching effect in molecular junctions

    NASA Astrophysics Data System (ADS)

    Gu, Lei; Fu, Hua-Hua

    2015-12-01

    Current-induced forces can excite molecules, polymers and other low-dimensional materials, which in turn leads to an effective gate voltage through Holstein interaction. Here, by taking a short asymmetric DNA junction as an example, and using the Langevin approach, we find that when suppression of charge transport by the effective gate voltage surpasses the current increase from an elevated voltage bias, the current-voltage (I-V) curves display strong negative differential resistance (NDR) and perfect current-switching characteristics. The asymmetric DNA chain differs in mechanical stability under inverse voltages and the I-V curve is asymmetric about inverse biases, which can be used to understand recent transport experiments on DNA chains, and meanwhile provides a new strategy to realize NDR in molecular junctions and other low-dimensional quantum systems.

  12. Current-induced forces: a new mechanism to induce negative differential resistance and current-switching effect in molecular junctions.

    PubMed

    Gu, Lei; Fu, Hua-Hua

    2015-12-04

    Current-induced forces can excite molecules, polymers and other low-dimensional materials, which in turn leads to an effective gate voltage through Holstein interaction. Here, by taking a short asymmetric DNA junction as an example, and using the Langevin approach, we find that when suppression of charge transport by the effective gate voltage surpasses the current increase from an elevated voltage bias, the current-voltage (I-V) curves display strong negative differential resistance (NDR) and perfect current-switching characteristics. The asymmetric DNA chain differs in mechanical stability under inverse voltages and the I-V curve is asymmetric about inverse biases, which can be used to understand recent transport experiments on DNA chains, and meanwhile provides a new strategy to realize NDR in molecular junctions and other low-dimensional quantum systems.

  13. Increased muscle size and strength from slow-movement, low-intensity resistance exercise and tonic force generation.

    PubMed

    Watanabe, Yuya; Tanimoto, Michiya; Ohgane, Akane; Sanada, Kiyoshi; Miyachi, Motohiko; Ishii, Naokata

    2013-01-01

    The authors investigated the effects of low-intensity resistance training on muscle size and strength in older men and women. Thirty-five participants (age 59-76 yr) were randomly assigned to 2 groups and performed low-intensity (50% of 1-repetition maximum) knee-extension and -flexion exercises with either slow movement and tonic force generation (LST; 3-s eccentric, 3-s concentric, and 1-s isometric actions with no rest between repetitions) or normal speed (LN; 1-s concentric and 1-s eccentric actions with 1-s rests between repetitions) twice a week for 12 wk (2-wk preparation and 10-wk intervention). The LST significantly increased thigh-muscle thickness, as well as isometric knee-extension and -flexion strength. The LN significantly improved strength, but its hypertrophic effect was limited. These results indicate that even for older individuals, the LST can be an effective method for gaining muscle mass and strength.

  14. Resistance of mature Arabidopsis plants to mechanical deformation in relation to g-force during development

    NASA Technical Reports Server (NTRS)

    Brown, A. H.

    1983-01-01

    Arabidopsis plants were grown in centrifuge tubes under well standardized culture conditions. Each plant was subjected to centrifugation (roots out) for 10 min at one of a series of centripetal forces between 7 and 390g. No deformation was observed in plants centrifuged at less than 35g. An 'average' degree of deformation was attained at about 60g. All plants exposed to more than 95g were maximally deformed but none was broken nor otherwise damaged irreversibly even at 390g. In every case new shoot growth continued normally after the centrifugation. A plant population grown on horizontal clinostats (0.5 rpm) under culture conditions exactly the same as for the upright plants responded to centrifugation stress in a way that was not substantially different from the response pattern of the plants cultured upright at 1g.

  15. Resistance of mature Arabidopsis plants to mechanical deformation in relation to g-force during development

    NASA Technical Reports Server (NTRS)

    Brown, A. H.

    1983-01-01

    Arabidopsis plants were grown in centrifuge tubes under well standardized culture conditions. Each plant was subjected to centrifugation (roots out) for 10 min at one of a series of centripetal forces between 7 and 390g. No deformation was observed in plants centrifuged at less than 35g. An 'average' degree of deformation was attained at about 60g. All plants exposed to more than 95g were maximally deformed but none was broken nor otherwise damaged irreversibly even at 390g. In every case new shoot growth continued normally after the centrifugation. A plant population grown on horizontal clinostats (0.5 rpm) under culture conditions exactly the same as for the upright plants responded to centrifugation stress in a way that was not substantially different from the response pattern of the plants cultured upright at 1g.

  16. Novel strategy to mitigate cathode catalyst degradation during air/air startup cycling via the atmospheric resistive switching mechanism of a hydrogen anode with a platinum catalyst supported on tantalum-doped titanium dioxide

    NASA Astrophysics Data System (ADS)

    Shintani, Haruhiko; Kojima, Yuya; Kakinuma, Katsuyoshi; Watanabe, Masahiro; Uchida, Makoto

    2015-10-01

    We propose a new strategy for alleviating the reverse current phenomenon using a unique "atmospheric resistive switching mechanism" (ARSM) of a metal oxide semiconductor support, such that the electrical resistivity changes depending on the gas atmosphere. The membrane-electrode assembly (MEA) using Ta-doped TiO2-supported platinum (Pt/Ta-TiO2) as the anode catalyst showed approximately one order of magnitude greater resistance in air than in hydrogen. The overpotential of the hydrogen oxidation reaction was negligible up to at least 1.5 A cm-2. The losses of electrochemically active surface area and carbon corrosion of the cathode catalyst during air/air startup cycling were significantly suppressed by the use of the Pt/Ta-TiO2 anode. The decrease in the degradation is attributed to a reduction of the reverse current due to a low oxygen reduction reaction rate at the anode, which showed high resistivity in air. These results demonstrate the effectiveness of the ARSM in mitigating cathode catalyst degradation during air/air startup cycling.

  17. Effects of low-intensity resistance exercise with slow movement and tonic force generation on muscular function in young men.

    PubMed

    Tanimoto, Michiya; Ishii, Naokata

    2006-04-01

    We investigated the acute and long-term effects of low-intensity resistance exercise (knee extension) with slow movement and tonic force generation on muscular size and strength. This type of exercise was expected to enhance the intramuscular hypoxic environment that might be a factor for muscular hypertrophy. Twenty-four healthy young men without experience of regular exercise training were assigned into three groups (n = 8 for each) and performed the following resistance exercise regimens: low-intensity [ approximately 50% of one-repetition maximum (1RM)] with slow movement and tonic force generation (3 s for eccentric and concentric actions, 1-s pause, and no relaxing phase; LST); high-intensity ( approximately 80% 1RM) with normal speed (1 s for concentric and eccentric actions, 1 s for relaxing; HN); low-intensity with normal speed (same intensity as for LST and same speed as for HN; LN). In LST and HN, the mean repetition maximum was 8RM. In LN, both intensity and amount of work were matched with those for LST. Each exercise session consisting of three sets was performed three times a week for 12 wk. In LST and HN, exercise training caused significant (P < 0.05) increases in cross-sectional area determined with MRI and isometric strength (maximal voluntary contraction) of the knee extensors, whereas no significant changes were seen in LN. Electromyographic and near-infrared spectroscopic analyses showed that one bout of LST causes sustained muscular activity and the largest muscle deoxygenation among the three types of exercise. The results suggest that intramuscular oxygen environment is important for exercise-induced muscular hypertrophy.

  18. Finite element analysis of the convergence of the centers of resistance and rotation in extreme moment-to-force ratios.

    PubMed

    Geramy, Allahyar; Tanne, Kazuo; Moradi, Meisam; Golshahi, Hamid; Farajzadeh Jalali, Yasamin

    2016-06-01

    The aim of this study was to investigate how very high and very low M/F ratios affect the location of the center of rotation (CRo). A 3D model of a mesiodistal slice of the mandible was used for this purpose. The model comprised the lower right central incisor, its PDL, the spongy and cortical bone, and a bracket on the labial surface of the bracket. A couple of 1N was applied to the bracket slot to find the level of the center of resistance (Cre). In a second stage, we attempted to produce bodily movement by applying the appropriate M/F ratio. M/F ratios of ±100, 200, 400, and 800 were applied to the last tenths of a millimeter of a pre-activated loop. Higher M/F ratios with positive or negative values, at constant force, increased both incisal and apical movements. The change in the tooth inclination before and after force application matched the difference produced by the different M/F ratios. It was found that a single center of rotation can be constructed for any tooth position. However, this single point does not act as the center of rotation during the entire movement.

  19. Sideways Force Produced During Disruptions

    NASA Astrophysics Data System (ADS)

    Strauss, H. R.; Paccagnella, R.; Breslau, J.; Jardin, S.; Sugiyama, L.

    2012-10-01

    We extend previous studies [1] of vertical displacement events (VDE) which can produce disruptions. The emphasis is on the non axisymmetric ``sideways'' wall force Fx. Simulations are performed using the M3D [2] code. A VDE expels magnetic flux through the resistive wall until the last closed flux surface has q < 3. At this point the plasma is unstable to an (m,n) = (2,1) mode. A theory of sideways force produced by this mode in the presence of a VDE is presented. The wall force depends strongly on γτw, where γ is the mode growth rate and τw is the wall resistive penetration time. The force Fx is largest when γτw is a constant of order unity, which depends on the initial conditions. For large values of γτw, the wall force asymptotes to a relatively smaller value, well below the critical value ITER is designed to withstand. The principle of disruption mitigation by massive gas injection is to cause a disruption with large γτw. [4pt] [1] H. R. Strauss, R. Paccagnella, and J. Breslau,Phys. Plasmas 17, 082505 (2010) [2] W. Park, E.V. Belova, G.Y. Fu, X. Tang, H.R. Strauss, L.E. Sugiyama, Phys. Plasmas 6, 1796 (1999).

  20. Medium-intensity, high-volume "hypertrophic" resistance training did not induce improvements in rapid force production in healthy older men.

    PubMed

    Walker, Simon; Peltonen, Heikki; Häkkinen, Keijo

    2015-06-01

    The aim of the study was to determine whether it is possible to improve both maximum and rapid force production using resistance training that is typically used to induce muscle hypertrophy in previously untrained older men. Subjects (60-72 years) performed 20 weeks of "hypertrophic" resistance training twice weekly (n = 27) or control (n = 11). Maximum dynamic and isometric leg press, as well as isometric force over 0-100 ms, and maximum concentric power tests were performed pre- and post-intervention. Muscle activity was assessed during these tests by surface electromyogram of the vastus lateralis and medialis muscles. Muscle hypertrophy was assessed by panoramic ultrasound of the vastus lateralis. The intervention group increased their maximum isometric (from 2268 ± 544 to 2538 ± 701 N) and dynamic force production (from 137 ± 24 to 165 ± 29 kg), and these changes were significantly different to control (isometric 12 ± 16 vs. 1 ± 9 %; dynamic 21 ± 12 vs. 2 ± 4 %). No within- or between-group differences were observed in rapid isometric force or concentric power. Relative increases in vastus lateralis cross-sectional area trended to be statistically greater in the intervention group (10 ± 8 vs. 3 ± 6 %, P = 0.061). It is recommendable that resistance training programs for older individuals integrate protocols emphasizing maximum force/muscle hypertrophy and rapid force production in order to induce comprehensive health-related and functionally important improvements in this population.

  1. Effects of heavy resistance training on maximal and explosive force production, endurance and serum hormones in adolescent handball players.

    PubMed

    Gorostiaga, E M; Izquierdo, M; Iturralde, P; Ruesta, M; Ibáñez, J

    1999-10-01

    To determine the effects of 6-weeks of heavy-resistance training on physical fitness and serum hormone status in adolescents (range 14-16 years old) 19 male handball players were divided into two different groups: a handball training group (NST, n = 10), and a handball and heavy-resistance strength training group (ST, n = 9). A third group of 4 handball goalkeepers of similar age served as a control group (C, n = 4). After the 6-week training period, the ST group showed an improvement in maximal dynamic strength of the leg extensors (12.2%; P < 0.01) and the upper extremity muscles (23%; P < 0.01), while no changes were observed in the NST and C groups. Similar differences were observed in the maximal isometric unilateral leg extension forces. The height of the vertical jump increased in the NST group from 29.5 (SD 4) cm to 31.4 (SD 5) cm (P < 0.05) while no changes were observed in the ST and C groups. A significant increase was observed in the ST group in the velocity of the throwing test [from 71.7 (SD 7) km x h(-1) to 74.0 (SD 7) km x h(-1); P < 0.001] during the 6-week period while no changes were observed in the NST and C groups. During a submaximal endurance test running at 11 km x h(-1), a significant decrease in blood lactate concentration occurred in the NST group [from 3.3 (SD 0.9) mmol x l(-1) to 2.4 (SD 0.8) mmol x l(-1); P < 0.01] during the experiment, while no change was observed in the ST or C groups. Finally, a significant increase (P < 0.01) was noted in the testosterone:cortisol ratio in the C group, while the increase in the NST group approached statistical significance (P < 0.08) and no changes in this ratio occurred in the ST group. The present findings suggested that the addition of 6-weeks of heavy resistance training to the handball training resulted in gains in maximal strength and throwing velocity but it compromised gains in leg explosive force production and endurance running. The tendency for a compromised testosterone:cortisol ratio

  2. Evaluation of wheelchair resistive forces during straight and turning trajectories across different wheelchair configurations using free-wheeling coast-down test.

    PubMed

    Lin, Jui-Te; Huang, Morris; Sprigle, Stephen

    2015-01-01

    The purpose of this study was to develop a simple approach to evaluate resistive frictional forces acting on manual wheelchairs (MWCs) during straight and turning maneuvers. Using a dummy-occupied MWC, decelerations were measured via axle-mounted encoders during a coast-down protocol that included straight trajectories and fixed-wheel turns. Eight coast-down trials were conducted to test repeatability and repeated on separate days to evaluate reliability. Without changing the inertia of the MWC system, three tire inflations were chosen to evaluate the sensitivity in discerning deceleration differences using effect sizes. The technique was also deployed to investigate the effect of different MWC masses and weight distributions on resistive forces. Results showed that the proposed coast-down technique had good repeatability and reliability in measuring decelerations and had good sensitivity in discerning differences in tire inflation, especially during turning. The results also indicated that increased loading on drive wheels reduced resistive losses in straight trajectories while increasing resistive losses during turning. During turning trajectories, the presence of tire scrub contributes significantly to the amount of resistive force. Overall, this new coast-down technique demonstrates satisfactory repeatability and sensitivity for detecting deceleration changes during straight and turning trajectories, indicating that it can be used to evaluate resistive loss of different MWC configurations and maneuvers.

  3. Turbine Design to Mitigate Forcing (POSTPRINT)

    DTIC Science & Technology

    2012-09-01

    43, No. 5, pp. 1042-1052. [52] Staubach, J. B., 2003, “Multidisciplinary Design Optimization , MDO, the Next Frontier of CAD / CAE in the Design of... design - optimization systems have been used effectively in conjunction with steady-state flow solvers to reduce the strength of shock waves... design where both rapid turn-around time and predictive accuracy are critical. Design - optimization systems are becoming more and more prevalent

  4. Design Strategies to Mitigate Unsteady Forcing (Preprint)

    DTIC Science & Technology

    2008-04-01

    the aerodynamic and mechanical damping Kielb and Abhari [31]. In addition, design- optimization systems have been used effectively in conjunction...increasing levels of damping (aerodynamic and/or mechanical) or by decreasing levels of unsteady pressures. Aerodynamically, an attractive option is to...and Abhari, R. S., 2001, “Experimental Study of Aerodynamic and Structural Damping in a Full-Scale Rotating Turbine,” ASME Paper No. 2001-GT- 0263

  5. Long-term resistance training improves force and unloaded shortening velocity of single muscle fibres of elderly women.

    PubMed

    Parente, Valeria; D'Antona, Giuseppe; Adami, Raffaella; Miotti, Danilo; Capodaglio, Paolo; De Vito, Giuseppe; Bottinelli, Roberto

    2008-11-01

    Four elderly women (78 +/- 4.3 years) were resistance trained (RT) for one year and needle biopsies of the vastus lateralis muscle were taken pre- and post-RT. A training intensity of 60% one-repetition maximum (1RM) was adopted for the entire duration of the study. Following RT, significant gain in isometric force of the quadriceps muscles was observed and MHC isoform distribution of vastus lateralis muscle showed a very significant shift from MHC-1 and MHC-2X towards MHC-2A, i.e. a bi-directional shift. A large population (n = 310) of individual skinned muscle fibres were dissected from biopsy samples and used for determination of cross-sectional area (CSA), specific force (Po/CSA) and unloaded shortening velocity (Vo) at 12 degrees C and maximum activation. Fibres were classified on the basis of their MHC isoform content determined by SDS-PAGE in three pure fibre types (1, 2A and 2X) and two hybrid fibre types (1-2A and 2AX). Whereas the CSA of individual muscle fibres did not change, Po/CSA was significantly higher in both type 1 and type 2A fibres post training. Vo of type 1 fibres was significantly higher post-training, whereas no change in Vo was observed in type 2A fibres. The number of pure type 2X fibres was very low especially post-training and did not enable a statistically significant comparison. The data suggest that in elderly women moderate and prolonged RT: (1) can determine similar adaptations in MHC distribution of skeletal muscle to those expected in young subjects; (2) can improve function of muscle fibres.

  6. Gas powered fluid gun with recoil mitigation

    DOEpatents

    Grubelich, Mark C.; Yonas, Gerold

    2016-03-01

    A gas powered fluid gun for propelling a stream or slug of a fluid at high velocity toward a target. Recoil mitigation is provided that reduces or eliminates the associated recoil forces, with minimal or no backwash. By launching a quantity of water in the opposite direction, net momentum forces are reduced or eliminated. Examples of recoil mitigation devices include a cone for making a conical fluid sheet, a device forming multiple impinging streams of fluid, a cavitating venturi, one or more spinning vanes, or an annular tangential entry/exit.

  7. Gas powered fluid gun with recoil mitigation

    DOEpatents

    Grubelich, Mark C; Yonas, Gerold

    2013-11-12

    A gas powered fluid gun for propelling a stream or slug of a fluid at high velocity toward a target. Recoil mitigation is provided that reduces or eliminates the associated recoil forces, with minimal or no backwash. By launching a quantity of water in the opposite direction, net momentum forces are reduced or eliminated. Examples of recoil mitigation devices include a cone for making a conical fluid sheet, a device forming multiple impinging streams of fluid, a cavitating venturi, one or more spinning vanes, or an annular tangential entry/exit.

  8. Returning home: forced conscription, reintegration, and mental health status of former abductees of the Lord's Resistance Army in northern Uganda

    PubMed Central

    Pham, Phuong N; Vinck, Patrick; Stover, Eric

    2009-01-01

    Background Since the late 1980s, the Lord's Resistance Army (LRA), a spiritualist rebel group in northern Uganda, has killed and mutilated thousands of civilians and abducted an estimated 52,000 to 75,000 people to serve as soldiers, porters, and sex slaves for its commanders. This study examines the types of violence to which former abductees have been exposed and the extent to which these acts have affected their psychological well-being. Methods This is a cross-sectional study of 2,875 individuals selected through a multi-stage stratified cluster sampling design conducted in 8 districts of northern Uganda. Multivariate logistic regressions were performed with symptoms for Post-traumatic Stress Disorder (PTSD) and depression as the main outcome measures. Results One-third of the respondents (33%) self-reported having experienced abduction (49% among the Acholi, the largest tribal group in northern Uganda). Over half (56%) of all the respondents and over two-thirds of those who experienced abduction met the criteria for symptoms of post-traumatic stress disorder (PTSD). Multivariate analysis shows that several factors increased the risk of former LRA abductees developing symptoms of PTSD. These factors included gender (females were more susceptible than males), being a member of the Acholi ethnic group, participating in or witnessing a cumulative number of traumatic events, and encountering difficulties re-integrating into communities after abduction. Factors associated with increased risk of meeting criteria for symptoms of depression included older age of males at the time of abduction, lower score on social relationship scale, high incidence of general traumatic event exposure, high incidence of forced acts of violence, and problems reintegrating into communities after abduction. Conclusion Abduction and forced conscription of civilians has affected the psychological well-being of a significant number of northern Ugandans. The sources of psychological trauma

  9. Returning home: forced conscription, reintegration, and mental health status of former abductees of the Lord's Resistance Army in northern Uganda.

    PubMed

    Pham, Phuong N; Vinck, Patrick; Stover, Eric

    2009-05-16

    Since the late 1980s, the Lord's Resistance Army (LRA), a spiritualist rebel group in northern Uganda, has killed and mutilated thousands of civilians and abducted an estimated 52,000 to 75,000 people to serve as soldiers, porters, and sex slaves for its commanders. This study examines the types of violence to which former abductees have been exposed and the extent to which these acts have affected their psychological well-being. This is a cross-sectional study of 2,875 individuals selected through a multi-stage stratified cluster sampling design conducted in 8 districts of northern Uganda. Multivariate logistic regressions were performed with symptoms for Post-traumatic Stress Disorder (PTSD) and depression as the main outcome measures. One-third of the respondents (33%) self-reported having experienced abduction (49% among the Acholi, the largest tribal group in northern Uganda). Over half (56%) of all the respondents and over two-thirds of those who experienced abduction met the criteria for symptoms of post-traumatic stress disorder (PTSD). Multivariate analysis shows that several factors increased the risk of former LRA abductees developing symptoms of PTSD. These factors included gender (females were more susceptible than males), being a member of the Acholi ethnic group, participating in or witnessing a cumulative number of traumatic events, and encountering difficulties re-integrating into communities after abduction. Factors associated with increased risk of meeting criteria for symptoms of depression included older age of males at the time of abduction, lower score on social relationship scale, high incidence of general traumatic event exposure, high incidence of forced acts of violence, and problems reintegrating into communities after abduction. Abduction and forced conscription of civilians has affected the psychological well-being of a significant number of northern Ugandans. The sources of psychological trauma are multiple, ranging from witnessing to

  10. How mothers mediate the social integration of their children conceived of forced marriage within the Lord's Resistance Army.

    PubMed

    Shanahan, Fiona; Veale, Angela

    2016-01-01

    This article aims to understand how formerly abducted young mothers mediate the social integration of their children conceived of forced marriage and sexual violence within the Lord's Resistance Army (LRA) in northern Uganda. Interviews and photographic methods were used in six Internally Displaced Persons Camps in northern Uganda. This article draws on data derived from ten mothers of thirteen children who were conceived in the LRA, five boys and eight girls. The analytic approach used was Interpretive Phenomenological Analysis (Smith & Osborn, 2008). The analysis identified turning points of sites of action where young formerly abducted mothers used diverse strategies to support the reintegration of their children born or conceived within the LRA. Six key turning points are identified, these are (a) participating in rituals and ceremonies, (b) naming, (c) adapting to changing family structures, (d) responding to discrimination against boys (e) managing disclosure and (f) sharing positive memories and identities. Formerly abducted young mothers mediate the social integration of their children by engaging in strategies to support and foster their wellbeing and social relationships. However, the contexts in which they are operating are highly constrained and the relational identities of children born in the LRA are fluid and potentially insecure within communities of return. Implications for policy and programming are discussed.

  11. Subsurface evaluation of the west parking lot and landfill 3 areas of Air Force Plant 4, Fort Worth, Texas, using two-dimensional direct-current resistivity profiling

    USGS Publications Warehouse

    Braun, Christopher L.; Jones, Sonya A.

    2002-01-01

    During September 1999, the U.S. Geological Survey made 10 two-dimensional direct-current resistivity profile surveys in the west parking lot and landfill 3 areas of Air Force Plant 4, Fort Worth, Texas, to identify subsurface areas of anomalously high or low resistivity that could indicate potential contamination, contaminant pathways, or anthropogenic structures. Six of the 10 surveys (transects) were in the west parking lot. Each of the inverted sections of these transects had anomalously high resistivities in the terrace alluvium/fill (the surficial subsurface layer) that probably were caused by highly resistive fill material. In addition, each of these transects had anomalously low resistivities in the Walnut Formation (a bedrock layer immediately beneath the alluvium/fill) that could have been caused by saturation of fractures within the Walnut Formation. A high-resistivity anomaly in the central part of the study area probably is associated with pea gravel fill used in construction of a French drain. Another high resistivity anomaly in the west parking lot, slightly southeast of the French drain, could be caused by dense nonaqueous-phase liquid in the Walnut Formation. The inverted sections of the four transects in the landfill 3 area tended to have slightly higher resistivities in both the alluvium/fill and the Walnut Formation than the transects in the west parking lot. The higher resistivities in the alluvium/fill could have been caused by drier conditions in grassy areas relative to conditions in the west parking lot. Higher resistivities in parts of the Walnut Formation also could be a function of drier conditions or variations in the lithology of the Walnut Formation. In addition to the 10 vertical sections, four horizontal sections at 2-meteraltitude intervals show generally increasing resistivity with decreasing altitude that most likely results from the increased influence of the Walnut Formation, which has a higher resistivity than the terrace

  12. Subsurface evaluation of the west parking lot and landfill 3 areas of Air Force Plant 4, Fort Worth, Texas, using two-dimensional direct-current resistivity profiling

    USGS Publications Warehouse

    Braun, Christopher L.; Jones, Sonya A.

    2002-01-01

    During September 1999, the U.S. Geological Survey made 10 two-dimensional direct-current resistivity profile surveys in the west parking lot and landfill 3 areas of Air Force Plant 4, Fort Worth, Texas, to identify subsurface areas of anomalously high or low resistivity that could indicate potential contamination, contaminant pathways, or anthropogenic structures. Six of the 10 surveys (transects) were in the west parking lot. Each of the inverted sections of these transects had anomalously high resistivities in the terrace alluvium/fill (the surficial subsurface layer) that probably were caused by highly resistive fill material. In addition, each of these transects had anomalously low resistivities in the Walnut Formation (a bedrock layer immediately beneath the alluvium/fill) that could have been caused by saturation of fractures within the Walnut Formation. A high-resistivity anomaly in the central part of the study area probably is associated with pea gravel fill used in construction of a French drain. Another high resistivity anomaly in the west parking lot, slightly southeast of the French drain, could be caused by dense nonaqueous-phase liquid in the Walnut Formation. The inverted sections of the four transects in the landfill 3 area tended to have slightly higher resistivities in both the alluvium/fill and the Walnut Formation than the transects in the west parking lot. The higher resistivities in the alluvium/fill could have been caused by drier conditions in grassy areas relative to conditions in the west parking lot. Higher resistivities in parts of the Walnut Formation also could be a function of drier conditions or variations in the lithology of the Walnut Formation. In addition to the 10 vertical sections, four horizontal sections at 2-meteraltitude intervals show generally increasing resistivity with decreasing altitude that most likely results from the increased influence of the Walnut Formation, which has a higher resistivity than the terrace

  13. An extract of Urtica dioica L. mitigates obesity induced insulin resistance in mice skeletal muscle via protein phosphatase 2A (PP2A).

    PubMed

    Obanda, Diana N; Ribnicky, David; Yu, Yongmei; Stephens, Jacqueline; Cefalu, William T

    2016-02-26

    The leaf extract of Urtica dioica L. (UT) has been reported to improve glucose homeostasis in vivo, but definitive studies on efficacy and mechanism of action are lacking. We investigated the effects of UT on obesity- induced insulin resistance in skeletal muscle. Male C57BL/6J mice were divided into three groups: low-fat diet (LFD), high-fat diet (HFD) and HFD supplemented with UT. Body weight, body composition, plasma glucose and plasma insulin were monitored. Skeletal muscle (gastrocnemius) was analyzed for insulin sensitivity, ceramide accumulation and the post translational modification and activity of protein phosphatase 2A (PP2A). PP2A is activated by ceramides and dephosphorylates Akt. C2C12 myotubes exposed to excess free fatty acids with or without UT were also evaluated for insulin signaling and modulation of PP2A. The HFD induced insulin resistance, increased fasting plasma glucose, enhanced ceramide accumulation and PP2A activity in skeletal muscle. Supplementation with UT improved plasma glucose homeostasis and enhanced skeletal muscle insulin sensitivity without affecting body weight and body composition. In myotubes, UT attenuated the ability of FFAs to induce insulin resistance and PP2A hyperactivity without affecting ceramide accumulation and PP2A expression. UT decreased PP2A activity through posttranslational modification that was accompanied by a reduction in Akt dephosphorylation.

  14. An extract of Urtica dioica L. mitigates obesity induced insulin resistance in mice skeletal muscle via protein phosphatase 2A (PP2A)

    PubMed Central

    Obanda, Diana N.; Ribnicky, David; Yu, Yongmei; Stephens, Jacqueline; Cefalu, William T.

    2016-01-01

    The leaf extract of Urtica dioica L. (UT) has been reported to improve glucose homeostasis in vivo, but definitive studies on efficacy and mechanism of action are lacking. We investigated the effects of UT on obesity- induced insulin resistance in skeletal muscle. Male C57BL/6J mice were divided into three groups: low-fat diet (LFD), high-fat diet (HFD) and HFD supplemented with UT. Body weight, body composition, plasma glucose and plasma insulin were monitored. Skeletal muscle (gastrocnemius) was analyzed for insulin sensitivity, ceramide accumulation and the post translational modification and activity of protein phosphatase 2A (PP2A). PP2A is activated by ceramides and dephosphorylates Akt. C2C12 myotubes exposed to excess free fatty acids with or without UT were also evaluated for insulin signaling and modulation of PP2A. The HFD induced insulin resistance, increased fasting plasma glucose, enhanced ceramide accumulation and PP2A activity in skeletal muscle. Supplementation with UT improved plasma glucose homeostasis and enhanced skeletal muscle insulin sensitivity without affecting body weight and body composition. In myotubes, UT attenuated the ability of FFAs to induce insulin resistance and PP2A hyperactivity without affecting ceramide accumulation and PP2A expression. UT decreased PP2A activity through posttranslational modification that was accompanied by a reduction in Akt dephosphorylation. PMID:26916435

  15. Bilateral symmetry of ground reaction force with a motor-controlled resistance exercise system using a mechanical advantage barbell for spaceflight.

    PubMed

    Paulus, David C; Settlage, Daniel M

    2012-01-01

    The reduced gravity experienced during spaceflight leads to muscle and bone atrophy, and resistance exercise has proven to be an effective countermeasure. Thus, a compact computer-controlled electric-motor resistance exercise system is being developed for NASA. In order to save power, space, and weight, the torque specifications of the motor were reduced by half because of a unique barbell design that employs a two-to-one mechanical advantage. Since the force-generating motor is on one side of the barbell, there is the potential for asymmetric barbell loading. Therefore, the purpose of this preliminary study is to compare the unilateral ground reaction forces (GRF) of the new barbell of the motor and ground sides. Multiple repetitions of fixed tempo deadlift exercise were performed with motor-controlled resistance using the new barbell. Unilateral GRF data was measured with a force plate under each foot, and the readings from each force plate are compared to each other. Results indicate the mechanical advantage barbell exercises have bilaterally asymmetric GRF compared to a theoretical 50-50 split, and the astronauts would need to alternate the left-right orientation to compensate for the asymmetry.

  16. Changes in muscle cross-sectional area, muscle force, and jump performance during 6 weeks of progressive whole-body vibration combined with progressive, high intensity resistance training

    PubMed Central

    Rosenberger, A.; Beijer, Å.; Johannes, B.; Schoenau, E.; Mester, J.; Rittweger, J.; Zange, J.

    2017-01-01

    Objectives: We hypothesized that progressive whole-body vibration (WBV) superimposed to progressive high intensity resistance training has greater effects on muscle cross-sectional area (CSA), muscle force of leg muscles, and jump performance than progressive high intensity resistance training alone. Methods: Two groups of healthy male subjects performed either 6 weeks of Resistive Vibration Exercise (RVE, squats and heel raises with WBV, n=13) or Resistive Exercise (RE, squats and heel raises without WBV, n=13). Squats under RVE required indispensable weight loading on the forefoot to damp harmful vibrations to the head. Time, intervention, and interaction effects were analyzed. Results: After 6 weeks of training, knee extensor CSA, isometric knee extension force, and counter movement jump height increased equally in both groups (time effect, P<0.001, P≤0.02, and P≤0.03, respectively), whereas only in RVE ankle plantar flexor CSA and isometric ankle plantar flexion force reached significance or a tendency, respectively, (time effect, P=0.015 and P=0.069, respectively; intervention effect also for the latter, P=0.006). Drop jump contact time did significantly more improve in RVE (interaction effect, P=0.042). Conclusions: RVE showed better training effects than RE only in plantar flexor muscles. RVE seems to be suitable in professional sports with a special focus on calf muscles. PMID:28574410

  17. Space Debris & its Mitigation

    NASA Astrophysics Data System (ADS)

    Kaushal, Sourabh; Arora, Nishant

    2012-07-01

    Space debris has become a growing concern in recent years, since collisions at orbital velocities can be highly damaging to functioning satellites and can also produce even more space debris in the process. Some spacecraft, like the International Space Station, are now armored to deal with this hazard but armor and mitigation measures can be prohibitively costly when trying to protect satellites or human spaceflight vehicles like the shuttle. This paper describes the current orbital debris environment, outline its main sources, and identify mitigation measures to reduce orbital debris growth by controlling these sources. We studied the literature on the topic Space Debris. We have proposed some methods to solve this problem of space debris. We have also highlighted the shortcomings of already proposed methods by space experts and we have proposed some modification in those methods. Some of them can be very effective in the process of mitigation of space debris, but some of them need some modification. Recently proposed methods by space experts are maneuver, shielding of space elevator with the foil, vaporizing or redirecting of space debris back to earth with the help of laser, use of aerogel as a protective layer, construction of large junkyards around international space station, use of electrodynamics tether & the latest method proposed is the use of nano satellites in the clearing of the space debris. Limitations of the already proposed methods are as follows: - Maneuvering can't be the final solution to our problem as it is the act of self-defence. - Shielding can't be done on the parts like solar panels and optical devices. - Vaporizing or redirecting of space debris can affect the human life on earth if it is not done in proper manner. - Aerogel has a threshold limit up to which it can bear (resist) the impact of collision. - Large junkyards can be effective only for large sized debris. In this paper we propose: A. The Use of Nano Tubes by creating a mesh

  18. Variation in resistive force selection during brief high intensity cycle ergometry: implications for power assessment and production in elite karate practitioners.

    PubMed

    Baker, Julien Steven; Davies, Bruce

    2006-01-01

    The purpose of this study was to measure power values generated in elite karate fighters during brief high intensity cycle ergometry when resistive forces were derived from total - body mass (TBM) or fat - free mass (FFM). Male international karate practitioners volunteered as participants (n = 11). Body density was calculated using hydrostatic weighing procedures with fat mass ascertained from body density values. Participants were required to pedal maximally on a cycle ergometer (Monark 864) against randomly assigned loads ranging from 70 g·kg(-1) - 95 g·kg(-1) (using a TBM or FFM protocol) for 8 seconds. The resistive force that produced the highest peak power output (PPO) for each protocol was considered optimal. Differences (p < 0.05) in peak power outputs were found between the TBM and FFM experimental condition (1164 ± 137 W vs. 1289 ± 145 W respectively). Differences were also recorded (p < 0.01) between pedal velocity and applied resistive forces (127 ± 8 rpm vs. 142 ± 7 rpm; 6.6 ± 1 kg vs. 5.5 ± 1 kg, respectively). No differences (p > 0.05) were observed between time to PPO, or heart rate when the TBM and FFM protocols were compared. The findings of this study suggest that when high intensity cycle ergometer resistive forces are derived from FFM, greater peak powers can be obtained consistently in karate athletes. Resistive forces that relate to the active muscle tissue utilised during this type of exercise may need to be explored in preference to protocols that include both lean and fat masses. The findings have implications for both exercise prescription and the evaluation of experimental results concerning karate athletes. Key PointsMethods for quantifying and measuring high intensity performance using high intensity cycle ergometry have received considerable attention in recent years.The assumption has been that the relationship between total - body mass (TBM) and fat - free mass (FFM) is the same.However, variations in body composition

  19. High-level iron mitigates fusaricidin-induced membrane damage and reduces membrane fluidity leading to enhanced drug resistance in Bacillus subtilis.

    PubMed

    Yu, Wen-Bang; Ye, Bang-Ce

    2016-05-01

    Fusaricidins are a class of cyclic lipopeptide antibiotics that have strong antifungal activities against plant pathogenic fungi and excellent bactericidal activities against Gram-positive bacteria. The mechanism through which fusaricidin exerts its action is not yet entirely clear. To investigate the mode of action of fusaricidin, we determined the physiological and transcriptional responses of Bacillus subtilis to fusaricidin treatment by using a systems-level approach. Our data show that fusaricidin rapidly induced the expression of σ(W) regulon and caused membrane damage in B. subtilis. We further demonstrated that ferric ions play multiple roles in the action of fusaricidin on B. subtilis. Iron deprivation blocked the formation of hydroxyl radical in the cells and significantly inhibited the bactericidal activity of fusaricidin. Conversely, high levels of iron (>2 mM) repressed the expression of BkdR regulon, resulting in a smaller cellular pool of branched-chain precursors for iso- and anteiso-branched fatty acids, which in turn led to a decrease in the proportion of branched-chain fatty acids in the membrane of B. subtilis. This change in membrane composition reduced its bilayer fluidity and increased its resistance to antimicrobial agents. In conclusion, our experiments uncovered some novel interactions and a synergism between cellular iron levels and drug resistance in Gram-positive bacteria. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Robust Interference Mitigation and Spread Spectrum Signaling

    DTIC Science & Technology

    2006-01-01

    AFRL-IF-RS-TR-2005-414 Final Technical Report January 2006 ROBUST INTERFERENCE MITIGATION AND SPREAD SPECTRUM SIGNALING State...reviewed by the Air Force Research Laboratory, Information Directorate, Public Affairs Office (IFOIPA) and is releasable to the National Technical ...s/ WARREN H. DEBANY JR., Technical Advisor Information Grid Division Information Directorate REPORT DOCUMENTATION PAGE

  1. Formation of closely packed Cu nanoparticle films by capillary immersion force for preparing low-resistivity Cu films at low temperature

    NASA Astrophysics Data System (ADS)

    Yokoyama, Shun; Motomiya, Kenichi; Takahashi, Hideyuki; Tohji, Kazuyuki

    2016-11-01

    Films made of closely packed Cu nanoparticles (NPs) were obtained by drop casting Cu NP inks. The capillary immersion force exerted during the drying of the inks caused the Cu NPs to attract each other, resulting in closely packed Cu NP films. The apparent density of the films was found to depend on the type of solvent in the ink because the capillary immersion force is affected by the solvent surface tension and dispersibility of Cu NPs in the solvent. The closely packed particulate structure facilitated the sintering of Cu NPs even at low temperature, leading to low-resistivity Cu films. The sintering was also enhanced with a decrease in the size of NPs used. We demonstrated that a closely packed particulate structure using Cu NPs with a mean diameter 61.7 nm showed lower resistivity (7.6 μΩ cm) than a traditionally made Cu NP film (162 μΩ cm) after heat treatment.

  2. 77 FR 58143 - Interagency Task Force on Antimicrobial Resistance (ITFAR): An Update of A Public Health Action...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-19

    ... Resistance (ITFAR): An Update of A Public Health Action Plan to Combat Antimicrobial Resistance AGENCY... within the Department of Health and Human Services, announce a public meeting and opening of a docket... outlined in ``A Public Health Action Plan to Combat Antimicrobial Resistance (Action Plan)''. Secondly, the...

  3. Mitigation Action Plan

    SciTech Connect

    Not Available

    1994-02-01

    This Mitigation Action Plan (MAP) focuses on mitigation commitments stated in the Supplemental Environmental Impact Statement (SEIS) and the Record of Decision (ROD) for the Naval Petroleum Reserve No. 1 (NPR-1). Specific commitments and mitigation implementation actions are listed in Appendix A-Mitigation Actions, and form the central focus of this MAP. They will be updated as needed to allow for organizational, regulatory, or policy changes. It is the intent of DOE to comply with all applicable federal, state, and local environmental, safety, and health laws and regulations. Eighty-six specific commitments were identified in the SEIS and associated ROD which pertain to continued operation of NPR-1 with petroleum production at the Maximum Efficient Rate (MER). The mitigation measures proposed are expected to reduce impacts as much as feasible, however, as experience is gained in actual implementation of these measures, some changes may be warranted.

  4. Passive-type rehabilitation system for upper limbs which can display the exact resistance force in the orientation opposite to hand motion.

    PubMed

    Haraguchi, Makoto; Furusho, Junji

    2013-06-01

    In these days, there are many patients with ataxia, which is paralysis caused by a brain stroke or asynergia. Early detection of functional deterioration and sufficient rehabilitative training are necessary for these patients. Rehabilitation support systems for upper limbs using force display devices are expected to quantify the effects of rehabilitative training and enhance the motivation of patients. The application of passive-type force display devices unactuated by motors is especially desirable for its high safety. There are, however, some orientations and positions for which it is difficult to display force in an unactuated force display systems using only passive elements. To solve this problem, a method for the improvement of controllability using larger number of brakes than the degree of freedom of system had been suggested. This method made it possible to display more various force power and orientations than could be done with previous systems. However, the system with the larger number of brakes often become huge system. In this study, we have developed a rehabilitation system for the upper limbs which use only the same number of brakes as the degree of freedom but can display the resistance force in the orientation opposite to operator's motion in any orientations and link posture: "Neo-PLEMO".

  5. Force cycles and force chains.

    PubMed

    Tordesillas, Antoinette; Walker, David M; Lin, Qun

    2010-01-01

    We examine the coevolution of N cycles and force chains as part of a broader study which is designed to quantitatively characterize the role of the laterally supporting contact network to the evolution of force chains. Here, we elucidate the rheological function of these coexisting structures, especially in the lead up to failure. In analogy to force chains, we introduce the concept of force cycles: N cycles whose contacts each bear above average force. We examine their evolution around force chains in a discrete element simulation of a dense granular material under quasistatic biaxial loading. Three-force cycles are shown to be stabilizing structures that inhibit relative particle rotations and provide strong lateral support to force chains. These exhibit distinct behavior from other cycles. Their population decreases rapidly during the initial stages of the strain-hardening regime-a trend that is suddenly interrupted and reversed upon commencement of force chain buckling prior to peak shear stress. Results suggest that the three-force cycles are called upon for reinforcements to ward off failure via shear banding. Ultimately though, the resistance to buckling proves futile; buckling wins under the combined effects of dilatation and increasing compressive load. The sudden increase in three-force cycles may thus be viewed as an indicator of imminent failure via shear bands.

  6. Electrostatic-Force-Assisted Dispensing Printing to Construct High-Aspect-Ratio of 0.79 Electrodes on a Textured Surface with Improved Adhesion and Contact Resistivity

    PubMed Central

    Shin, Dong-Youn; Yoo, Sung-Soo; Song, Hee-eun; Tak, Hyowon; Byun, Doyoung

    2015-01-01

    As a novel route to construct fine and abnormally high-aspect-ratio electrodes with excellent adhesion and reduced contact resistivity on a textured surface, an electrostatic-force-assisted dispensing printing technique is reported and compared with conventional dispensing and electrohydrodynamic jet printing techniques. The electrostatic force applied between a silver paste and the textured surface of a crystalline silicon solar cell wafer significantly improves the physical adhesion of the electrodes, whereas those fabricated using a conventional dispensing printing technique peel off with a silver paste containing 2 wt% of a fluorosurfactant. Moreover, the contact resistivity and dimensionless deviation of total resistance are significantly reduced from 2.19 ± 1.53 mΩ·cm2 to 0.98 ± 0.92 mΩ·cm2 and from 0.10 to 0.03, respectively. By utilizing electrodes with an abnormally high-aspect-ratio of 0.79 (the measured thickness and width are 30.4 μm and 38.3 μm, respectively), the cell efficiency is 17.2% on a polycrystalline silicon solar cell with an emitter sheet resistance of 60 Ω/sq. This cell efficiency is considerably higher than previously reported values obtained using a conventional electrohydrodynamic jet printing technique, by +0.48–3.5%p. PMID:26576857

  7. Electrostatic-Force-Assisted Dispensing Printing to Construct High-Aspect-Ratio of 0.79 Electrodes on a Textured Surface with Improved Adhesion and Contact Resistivity

    NASA Astrophysics Data System (ADS)

    Shin, Dong-Youn; Yoo, Sung-Soo; Song, Hee-Eun; Tak, Hyowon; Byun, Doyoung

    2015-11-01

    As a novel route to construct fine and abnormally high-aspect-ratio electrodes with excellent adhesion and reduced contact resistivity on a textured surface, an electrostatic-force-assisted dispensing printing technique is reported and compared with conventional dispensing and electrohydrodynamic jet printing techniques. The electrostatic force applied between a silver paste and the textured surface of a crystalline silicon solar cell wafer significantly improves the physical adhesion of the electrodes, whereas those fabricated using a conventional dispensing printing technique peel off with a silver paste containing 2 wt% of a fluorosurfactant. Moreover, the contact resistivity and dimensionless deviation of total resistance are significantly reduced from 2.19 ± 1.53 mΩ·cm2 to 0.98 ± 0.92 mΩ·cm2 and from 0.10 to 0.03, respectively. By utilizing electrodes with an abnormally high-aspect-ratio of 0.79 (the measured thickness and width are 30.4 μm and 38.3 μm, respectively), the cell efficiency is 17.2% on a polycrystalline silicon solar cell with an emitter sheet resistance of 60 Ω/sq. This cell efficiency is considerably higher than previously reported values obtained using a conventional electrohydrodynamic jet printing technique, by +0.48-3.5%p.

  8. Electrostatic-Force-Assisted Dispensing Printing to Construct High-Aspect-Ratio of 0.79 Electrodes on a Textured Surface with Improved Adhesion and Contact Resistivity.

    PubMed

    Shin, Dong-Youn; Yoo, Sung-Soo; Song, Hee-eun; Tak, Hyowon; Byun, Doyoung

    2015-11-18

    As a novel route to construct fine and abnormally high-aspect-ratio electrodes with excellent adhesion and reduced contact resistivity on a textured surface, an electrostatic-force-assisted dispensing printing technique is reported and compared with conventional dispensing and electrohydrodynamic jet printing techniques. The electrostatic force applied between a silver paste and the textured surface of a crystalline silicon solar cell wafer significantly improves the physical adhesion of the electrodes, whereas those fabricated using a conventional dispensing printing technique peel off with a silver paste containing 2 wt% of a fluorosurfactant. Moreover, the contact resistivity and dimensionless deviation of total resistance are significantly reduced from 2.19 ± 1.53 mΩ · cm(2) to 0.98 ± 0.92 mΩ · cm(2) and from 0.10 to 0.03, respectively. By utilizing electrodes with an abnormally high-aspect-ratio of 0.79 (the measured thickness and width are 30.4 μm and 38.3 μm, respectively), the cell efficiency is 17.2% on a polycrystalline silicon solar cell with an emitter sheet resistance of 60 Ω/sq. This cell efficiency is considerably higher than previously reported values obtained using a conventional electrohydrodynamic jet printing technique, by +0.48-3.5%p.

  9. Estimation of the radial force on the tokamak vessel wall during fast transient events

    SciTech Connect

    Pustovitov, V. D.

    2016-11-15

    The radial force balance in a tokamak during fast transient events with a duration much shorter than the resistive time of the vacuum vessel wall is analyzed. The aim of the work is to analytically estimate the resulting integral radial force on the wall. In contrast to the preceding study [Plasma Phys. Rep. 41, 952 (2015)], where a similar problem was considered for thermal quench, simultaneous changes in the profiles and values of the pressure and plasma current are allowed here. Thereby, the current quench and various methods of disruption mitigation used in the existing tokamaks and considered for future applications are also covered. General formulas for the force at an arbitrary sequence or combination of events are derived, and estimates for the standard tokamak model are made. The earlier results and conclusions are confirmed, and it is shown that, in the disruption mitigation scenarios accepted for ITER, the radial forces can be as high as in uncontrolled disruptions.

  10. Mitigation Monitoring Plan

    SciTech Connect

    Not Available

    1992-09-01

    The Final Supplemental Environmental Impact Report (SEIR) (September 1992) for the Proposed Renewal of the Contract between the United States Department of Energy and The Regents of the University of California for the Operation and Management of the Lawrence Berkeley Laboratory identifies the environmental impacts associated with renewing the contract and specifies a series of measures designed to mitigate adverse impacts to the environment. This Mitigation Monitoring Plan describes the procedures the University will use to implement the mitigation measures adopted in connection with the approval of the Contract.

  11. Effects of whole-body low-intensity resistance training with slow movement and tonic force generation on muscular size and strength in young men.

    PubMed

    Tanimoto, Michiya; Sanada, Kiyoshi; Yamamoto, Kenta; Kawano, Hiroshi; Gando, Yuko; Tabata, Izumi; Ishii, Naokata; Miyachi, Motohiko

    2008-11-01

    Our previous study showed that relatively low-intensity (approximately 50% one-repetition maximum [1RM]) resistance training (knee extension) with slow movement and tonic force generation (LST) caused as significant an increase in muscular size and strength as high-intensity (approximately 80% 1RM) resistance training with normal speed (HN). However, that study examined only local effects of one type of exercise (knee extension) on knee extensor muscles. The present study was performed to examine whether a whole-body LST resistance training regimen is as effective on muscular hypertrophy and strength gain as HN resistance training. Thirty-six healthy young men without experience of regular resistance training were assigned into three groups (each n = 12) and performed whole-body resistance training regimens comprising five types of exercise (vertical squat, chest press, latissimus dorsi pull-down, abdominal bend, and back extension: three sets each) with LST (approximately 55-60% 1RM, 3 seconds for eccentric and concentric actions, and no relaxing phase); HN (approximately 80-90% 1RM, 1 second for concentric and eccentric actions, 1 second for relaxing); and a sedentary control group (CON). The mean repetition maximum was eight-repetition maximum in LST and HN. The training session was performed twice a week for 13 weeks. The LST training caused significant (p < 0.05) increases in whole-body muscle thickness (6.8 +/- 3.4% in a sum of six sites) and 1RM strength (33.0 +/- 8.8% in a sum of five exercises) comparable with those induced by HN training (9.1 +/- 4.2%, 41.2 +/- 7.6% in each measurement item). There were no such changes in the CON group. The results suggest that a whole-body LST resistance training regimen is as effective for muscular hypertrophy and strength gain as HN resistance training.

  12. Combustion instability mitigation by magnetic fields

    NASA Astrophysics Data System (ADS)

    Jocher, Agnes; Pitsch, Heinz; Gomez, Thomas; Bonnety, Jérôme; Legros, Guillaume

    2017-06-01

    The present interdisciplinary study combines electromagnetics and combustion to unveil an original and basic experiment displaying a spontaneous flame instability that is mitigated as the non-premixed sooting flame experiences a magnetic perturbation. This magnetic instability mitigation is reproduced by direct numerical simulations to be further elucidated by a flow stability analysis. A key role in the stabilization process is attributed to the momentum and thermochemistry coupling that the magnetic force, acting mainly on paramagnetic oxygen, contributes to sustain. The spatial local stability analysis based on the numerical simulations shows that the magnetic field tends to reduce the growth rates of small flame perturbations.

  13. Combustion instability mitigation by magnetic fields.

    PubMed

    Jocher, Agnes; Pitsch, Heinz; Gomez, Thomas; Bonnety, Jérôme; Legros, Guillaume

    2017-06-01

    The present interdisciplinary study combines electromagnetics and combustion to unveil an original and basic experiment displaying a spontaneous flame instability that is mitigated as the non-premixed sooting flame experiences a magnetic perturbation. This magnetic instability mitigation is reproduced by direct numerical simulations to be further elucidated by a flow stability analysis. A key role in the stabilization process is attributed to the momentum and thermochemistry coupling that the magnetic force, acting mainly on paramagnetic oxygen, contributes to sustain. The spatial local stability analysis based on the numerical simulations shows that the magnetic field tends to reduce the growth rates of small flame perturbations.

  14. Characterization of heat loads from mitigated and unmitigated vertical displacement events in DIII-D

    NASA Astrophysics Data System (ADS)

    Hollmann, E. M.; Commaux, N.; Eidietis, N. W.; Humphreys, D. A.; Jernigan, T. J.; Lasnier, C. J.; Moyer, R. A.; Pitts, R. A.; Sugihara, M.; Strait, E. J.; Watkins, J.; Wesley, J. C.

    2013-06-01

    Experiments have been conducted on the DIII-D tokamak to study the distribution and repeatability of heat loads and vessel currents resulting from vertical displacement events (VDEs). For unmitigated VDEs, the radiated power fraction appears to be of order 50%, with the remaining power dominantly conducted to the vessel walls. Shot-to-shot scatter in heat loads measured at one toroidal location is not large (<±50%), suggesting that toroidal asymmetries in conducted heat loads are not large. Conducted heat loads are clearly observed during the current quench (CQ) of both mitigated and unmitigated disruptions. Significant poloidal asymmetries in heat loads and radiated power are often observed in the experiments but are not yet understood. Energy dissipated resistively in the conducting walls during the CQ appears to be small (<5%). The mitigating effect of neon massive gas injection (MGI) as a function of MGI trigger delay has also been studied. Improved mitigation is observed as the MGI trigger delay is decreased. For sufficiently early MGI mitigation, close to 100% radiated energy and a reduction of roughly a factor 2 in vessel forces is achieved.

  15. Characterization of heat loads from mitigated and unmitigated vertical displacement events in DIII-D

    SciTech Connect

    Hollmann, E. M.; Moyer, R. A.; Commaux, N.; Jernigan, T. J.; Eidietis, N. W.; Humphreys, D. A.; Strait, E. J.; Wesley, J. C.; Lasnier, C. J.; Pitts, R. A.; Sugihara, M.; Watkins, J.

    2013-06-15

    Experiments have been conducted on the DIII-D tokamak to study the distribution and repeatability of heat loads and vessel currents resulting from vertical displacement events (VDEs). For unmitigated VDEs, the radiated power fraction appears to be of order 50%, with the remaining power dominantly conducted to the vessel walls. Shot-to-shot scatter in heat loads measured at one toroidal location is not large (<±50%), suggesting that toroidal asymmetries in conducted heat loads are not large. Conducted heat loads are clearly observed during the current quench (CQ) of both mitigated and unmitigated disruptions. Significant poloidal asymmetries in heat loads and radiated power are often observed in the experiments but are not yet understood. Energy dissipated resistively in the conducting walls during the CQ appears to be small (<5%). The mitigating effect of neon massive gas injection (MGI) as a function of MGI trigger delay has also been studied. Improved mitigation is observed as the MGI trigger delay is decreased. For sufficiently early MGI mitigation, close to 100% radiated energy and a reduction of roughly a factor 2 in vessel forces is achieved.

  16. Different cadences and resistances in sub-maximal synchronous handcycling in able-bodied men: Effects on efficiency and force application

    PubMed Central

    Vegter, Riemer J. K.; Hensen, Alexander H. R.; Wagner, Heiko; van der Woude, Lucas H. V.

    2017-01-01

    Background With the introduction of an add-on handcycle, a crank system that can be placed in front of a wheelchair, handcycling was made widely available for daily life. With it, people go into town more easily, e.g. to do groceries; meet up with friends, etc. They have more independency and can be socially active. Our aim is to explore some settings of the handcycle, so that it can be optimally used as a transportation device. Therefore, the effects of cadence and added resistance on gross mechanical efficiency and force application during sub-maximal synchronous handcycling were investigated. We hypothesized that a cadence of 52 rpm with a higher resistance (35 W) would lead to a higher gross mechanical efficiency and a more tangential force application than a higher cadence of 70 rpm and no extra resistance (15 W). Methods Twelve able-bodied men rode in an instrumented add-on handcycle on a motorized level treadmill at 1.94 m/s. They performed three sessions of three four-minute blocks of steady state exercise. Gear (70, 60 and 52 rpm) was changed in-between the blocks and resistance (rolling resistance +0 W, +10 W, +20 W) was changed across sessions, both in a counterbalanced order. 3D force production, oxygen uptake and heart rate were measured continuously. Gross mechanical efficiency (ME) and fraction of effective force (FEF) were calculated as main outcomes. The effects of cadence and resistance were analyzed using a repeated measures ANOVA (P<0.05) with Bonferroni-corrected post-hoc pairwise comparisons. Results With a decrease in cadence a slight increase in ME (70 rpm: 5.5 (0.2)%, 60 rpm: 5.7 (0.2)%, 52 rpm: 5.8 (0.2)%, P = 0.008, η2p = 0.38), while an increase in FEF (70 rpm: 58.0 (3.2)%, 60 rpm: 66.0 (2.8)%, 52 rpm: 71.3 (2.3)%, P<0.001, η2p = 0.79) is seen simultaneously. Also with an increase in resistance an increase in ME (+0 W: 4.0 (0.2)%, +10 W: 6.0 (0.3)%, +20 W: 7.0 (0.2)%, P<0.001, η2p = 0.92) and FEF (+0 W: 59.0 (2.9)%, +10 W: 66.1 (3

  17. Different cadences and resistances in sub-maximal synchronous handcycling in able-bodied men: Effects on efficiency and force application.

    PubMed

    Kraaijenbrink, Cassandra; Vegter, Riemer J K; Hensen, Alexander H R; Wagner, Heiko; van der Woude, Lucas H V

    2017-01-01

    With the introduction of an add-on handcycle, a crank system that can be placed in front of a wheelchair, handcycling was made widely available for daily life. With it, people go into town more easily, e.g. to do groceries; meet up with friends, etc. They have more independency and can be socially active. Our aim is to explore some settings of the handcycle, so that it can be optimally used as a transportation device. Therefore, the effects of cadence and added resistance on gross mechanical efficiency and force application during sub-maximal synchronous handcycling were investigated. We hypothesized that a cadence of 52 rpm with a higher resistance (35 W) would lead to a higher gross mechanical efficiency and a more tangential force application than a higher cadence of 70 rpm and no extra resistance (15 W). Twelve able-bodied men rode in an instrumented add-on handcycle on a motorized level treadmill at 1.94 m/s. They performed three sessions of three four-minute blocks of steady state exercise. Gear (70, 60 and 52 rpm) was changed in-between the blocks and resistance (rolling resistance +0 W, +10 W, +20 W) was changed across sessions, both in a counterbalanced order. 3D force production, oxygen uptake and heart rate were measured continuously. Gross mechanical efficiency (ME) and fraction of effective force (FEF) were calculated as main outcomes. The effects of cadence and resistance were analyzed using a repeated measures ANOVA (P<0.05) with Bonferroni-corrected post-hoc pairwise comparisons. With a decrease in cadence a slight increase in ME (70 rpm: 5.5 (0.2)%, 60 rpm: 5.7 (0.2)%, 52 rpm: 5.8 (0.2)%, P = 0.008, η2p = 0.38), while an increase in FEF (70 rpm: 58.0 (3.2)%, 60 rpm: 66.0 (2.8)%, 52 rpm: 71.3 (2.3)%, P<0.001, η2p = 0.79) is seen simultaneously. Also with an increase in resistance an increase in ME (+0 W: 4.0 (0.2)%, +10 W: 6.0 (0.3)%, +20 W: 7.0 (0.2)%, P<0.001, η2p = 0.92) and FEF (+0 W: 59.0 (2.9)%, +10 W: 66.1 (3.4)%, +20 W: 70.2 (2.4)%, P<0

  18. Lunar Dust Mitigation Screens

    NASA Astrophysics Data System (ADS)

    Knutson, Shawn; Holloway, Nancy

    With plans for the United States to return to the moon, and establish a sustainable human presence on the lunar surface many issues must be successfully overcome. Lunar dust is one of a number of issues with the potential to create a myriad of problems if not adequately addressed. Samples of dust brought back from Apollo missions show it to be soft, yet sharp and abrasive. The dust consists of a variety of morphologies including spherical, angular blocks, shards, and a number of irregular shapes. One of the main issues with lunar dust is its attraction to stick to anything it comes in contact with (i.e. astronauts, equipment, habitats, etc.). Ionized radiation from the sun strikes the moon's surface and creates an electrostatic charge on the dust. Further, the dust harbors van der Waals forces making it especially difficult to separate once it sticks to a surface. During the Apollo missions, it was discovered that trying to brush the lunar dust from spacesuits was not effective, and rubbing it caused degradation of the suit material. Further, when entering the lunar module after moonwalks, the astronauts noted that the dust was so prolific inside the cabin that they inhaled and ingested it, causing at least one of them, Harrison "Jack" Schmidt, to report irritation of the throat and lungs. It is speculated that the dust could also harm an astronaut's nervous and cardiovascular systems, especially during an extended stay. In addition to health issues, the dust can also cause problems by scouring reflective coatings off of thermal blankets, and roughening surfaces of windows and optics. Further, panels on solar cells and photovoltaics can also be compromised due to dust sticking on the surfaces. Lunar dust has the capacity to penetrate seals, interfere with connectors, as well as mechanisms on digging machines, all of which can lead to problems and failure. To address lunar dust issues, development of electrostatic screens to mitigate dust on sur-faces is currently

  19. Mitigation win-win

    NASA Astrophysics Data System (ADS)

    Moran, Dominic; Lucas, Amanda; Barnes, Andrew

    2013-07-01

    Win-win messages regarding climate change mitigation policies in agriculture tend to oversimplify farmer motivation. Contributions from psychology, cultural evolution and behavioural economics should help to design more effective policy.

  20. Dust Mitigation Vehicle

    NASA Technical Reports Server (NTRS)

    Cardiff, Eric H.

    2011-01-01

    A document describes the development and demonstration of an apparatus, called a dust mitigation vehicle, for reducing the amount of free dust on the surface of the Moon. The dust mitigation vehicle would be used to pave surfaces on the Moon to prevent the dust from levitating or adhering to surfaces. The basic principle of operation of these apparatuses is to use a lens or a dish mirror to concentrate solar thermal radiation onto a small spot to heat lunar regolith. In the case of the prototype dust mitigation vehicle, a Fresnel lens was used to heat a surface layer of regolith sufficiently to sinter or melt dust grains into a solid mass. The prototype vehicle has demonstrated paving rates up to 1.8 square meters per day. The proposed flight design of the dust mitigation vehicle is also described.

  1. Mitigation Banking Factsheet

    EPA Pesticide Factsheets

    A mitigation bank is an aquatic resource area that has been restored, established, enhanced, or preserved for the purpose of providing compensation for unavoidable impacts to aquatic resources permitted under Section 404

  2. CWA Section 404 Mitigation

    EPA Pesticide Factsheets

    The Council on Environmental Quality has defined mitigation in its implementing regulations for the National Environmental Policy Act to include avoiding, minimizing, rectifying, reducing over time, and compensating for impacts.

  3. Orbital Debris Mitigation

    NASA Technical Reports Server (NTRS)

    Kelley, R. L.; Jarkey, D. R.; Stansbery, G.

    2014-01-01

    Policies on limiting orbital debris are found throughout the US Government, many foreign space agencies, and as adopted guidelines in the United Nations. The underlying purpose of these policies is to ensure the environment remains safe for the operation of robotic and human spacecraft in near- Earth orbit. For this reason, it is important to consider orbital debris mitigation during the design of all space vehicles. Documenting compliance with the debris mitigation guidelines occurs after the vehicle has already been designed and fabricated for many CubeSats, whereas larger satellites are evaluated throughout the design process. This paper will provide a brief explanation of the US Government Orbital Debris Mitigation Standard Practices, a discussion of international guidelines, as well as NASA's process for compliance evaluation. In addition, it will discuss the educational value of considering orbital debris mitigation requirements as a part of student built satellite design.

  4. Appalachian Stream Mitigation Workshop

    EPA Pesticide Factsheets

    A 5 day workshop in 2011 developed for state and federal regulatory and resource agencies, who review, comment on and/or approve compensatory mitigation plans for surface coal mining projects in Appalachia

  5. The effect of resist dissolution process on pattern formation variability: an in situ analysis using high-speed atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Santillan, Julius Joseph; Shichiri, Motoharu; Itani, Toshiro

    2015-03-01

    This work focuses on the application of a high speed atomic force microscope for the in situ visualization / quantification of the pattern formation phenomenon during resist dissolution. Specifically, this paper discusses on the quantification of various factors (e.g. pattern roughness, defects, etc.) that affect pattern quality. Comparing two typical positive-tone, extreme-ultraviolet lithography resists of dissimilar lithographic performance, results show that the differences in LER between such resists already exists even during the resist dissolution. This implies the significance of the dissolution process in further improving the final LER of lines-and-spaces (L/S) patterns. Moreover, results have shown the effectiveness of applying the same analysis technique in understanding pattern defect dynamics during dissolution, not only for L/S but also for contact hole (CH) patterns. Preliminary investigations on CH pattern formation during dissolution showed position-dependent variabilities / randomness in the timing of CH formation. Such variabilities in timing imply possible pointers in defining the origin of missing CH defects, from the resist dissolution point-of-view.

  6. Sidoarjo mudflow phenomenon and its mitigation efforts

    NASA Astrophysics Data System (ADS)

    Wibowo, H. T.; Williams, V.

    2009-12-01

    Hot mud first erupted in Siring village, Porong, Sidoarjo May 29th 2006. The mud first appeared approximately 200 meters from Banjarpanji-1 gas-drilling well. The mud volume increased day by day, from 5000 cubic meters per day on June 2006 to 50,000 cubic meters per day during the last of 2006, and then increased to 100,000-120,000 cubic meters per day during 2007. Flow still continues at a high rate. Moreover, as the water content has gone down, the clast content has gone up. Consequently, there is now the threat of large amounts of solid material being erupted throughout the area. Also, there is the issue of subsurface collapse and ground surface subsidence. The Indonesian government has set up a permanent team to support communities affected by the mudflow that has swamped a number of villages near LUSI. Toll roads, railway tracks and factories also have been submerged and over 35,000 people have been displaced to date. The Sidoarjo Mudflow Mitigation Agency [SMMA, BPLS (Indonesia)] replaces a temporary team called National Team PSLS which was installed for seven months and ended their work on 7 April 2007. BPLS was set up by Presidential Regulation No. 14 / 2007, and it will have to cover the costs related to the social impact of the disaster, especially outside the swamped area. BPLS is the central government institution designated to handle the disaster by coordination with both the drilling company and local (provincial and district) governments. It takes a comprehensive, integrated and holistic approach for its mission and challenges. Those are: 1) How to stop the mudflow, 2) How to mitigate the impacts of the mudflow, and 3) How to minimize the social, economic, environmental impacts, and infrastructure impacts. The mudflow mitigation efforts were constrained by dynamic geology conditions, as well as resistance to certain measures by residents of impacted areas. Giant dykes were built to retain the spreading mud, and the mudflow from the main vent was

  7. Quantitative estimation of electro-osmosis force on charged particles inside a borosilicate resistive-pulse sensor.

    PubMed

    Ghobadi, Mostafa; Yuqian Zhang; Rana, Ankit; Esfahani, Ehsan T; Esfandiari, Leyla

    2016-08-01

    Nano and micron-scale pore sensors have been widely used for biomolecular sensing application due to its sensitive, label-free and potentially cost-effective criteria. Electrophoretic and electroosmosis are major forces which play significant roles on the sensor's performance. In this work, we have developed a mathematical model based on experimental and simulation results of negatively charged particles passing through a 2μm diameter solid-state borosilicate pore under a constant applied electric field. The mathematical model has estimated the ratio of electroosmosis force to electrophoretic force on particles to be 77.5%.

  8. Precise control of surface electrostatic forces on polymer brush layers with opposite charges for resistance to protein adsorption.

    PubMed

    Sakata, Sho; Inoue, Yuuki; Ishihara, Kazuhiko

    2016-10-01

    Various molecular interaction forces are generated during protein adsorption process on material surfaces. Thus, it is necessary to control them to suppress protein adsorption and the subsequent cell and tissue responses. A series of binary copolymer brush layers were prepared via surface-initiated atom transfer radical polymerization, by mixing the cationic monomer unit and anionic monomer unit randomly in various ratios. Surface characterization revealed that the constructed copolymer brush layers exhibited an uniform super-hydrophilic nature and different surface potentials. The strength of the electrostatic interaction forces operating on these mixed-charge copolymer brush surfaces was evaluated quantitatively using force-versus-distance (f-d) curve measurements by atomic force microscopy (AFM) and probes modified by negatively charged carboxyl groups or positively charged amino groups. The electrostatic interaction forces were determined based on the charge ratios of the copolymer brush layers. Notably, the surface containing equivalent cationic/anionic monomer units hardly interacted with both the charged groups. Furthermore, the protein adsorption force and the protein adsorption mass on these surfaces were examined by AFM f-d curve measurement and surface plasmon resonance measurement, respectively. To clarify the influence of the electrostatic interaction on the protein adsorption behavior on the surface, three kinds of proteins having negative, positive, and relatively neutral net charges under physiological conditions were used in this study. We quantitatively demonstrated that the amount of adsorbed proteins on the surfaces would have a strong correlation with the strength of surface-protein interaction forces, and that the strength of surface-protein interaction forces would be determined from the combination between the properties of the electrostatic interaction forces on the surfaces and the charge properties of the proteins. Especially, the

  9. Core temperatures during major abdominal surgery in patients warmed with new circulating-water garment, forced-air warming, or carbon-fiber resistive-heating system.

    PubMed

    Hasegawa, Kenji; Negishi, Chiharu; Nakagawa, Fumitoshi; Ozaki, Makoto

    2012-04-01

    It has been reported that recently developed circulating-water garments transfer more heat than a forced-air warming system. The authors evaluated the hypothesis that circulating-water leg wraps combined with a water mattress better maintain intraoperative core temperature ≥36°C than either forced-air warming or carbon-fiber resistive heating during major abdominal surgery. Thirty-six patients undergoing open abdominal surgery were randomly assigned to warming with: (1) circulating-water leg wraps combined with a full-length circulating-water mattress set at 42°C, (2) a lower-body forced-air cover set on high (≈43°C), and (3) a carbon-fiber resistive-heating cover set at 42°C. Patients were anesthetized with general anesthesia combined with continuous epidural analgesia. The primary outcome was intraoperative tympanic-membrane temperature ≥36°C. In the 2 h after anesthesia induction, core temperature decreased 1.0 ± 0.5°C in the forced-air group, 0.9 ± 0.2°C in the carbon-fiber group, and 0.4 ± 0.4°C in the circulating-water leg wraps and mattress group (P < 0.05 vs. forced-air and carbon-fiber heating). At the end of surgery, core temperature was 0.2 ± 0.7°C above preoperative values in the circulating-water group but remained 0.6 ± 0.9°C less in the forced-air and 0.6 ± 0.4°C less in the carbon-fiber groups (P < 0.05 vs. carbon fiber). The combination of circulating-water leg wraps and a mattress better maintain intraoperative core temperature than did forced-air and carbon-fiber warming systems.

  10. The lake acidification mitigation project (LAMP)

    SciTech Connect

    Porcella, D.P. )

    1987-01-01

    In areas where there is limited capacity to resist input of acid deposition, acid soils and surface waters have affected natural communities and man's uses of the environment. In response to problems of acid soils, farmers added limestone materials to their soil during Roman times; this method of agricultural management continues today. The addition of limestone (CaCo/sub 3/), called liming, has been used more recently to mitigate acidic conditions in lakes and streams. Liming neutralizes acidity directly, provides buffering as acid neutralizing capacity (ANC) or alkalinity, and increases calcium ion concentration which mitigates toxicity in low ionic strength waters. The Lake Acidification Mitigation Project (LAMP) has the objective of identifying and quantifying environmental impacts of liming, and evaluating the effectiveness of liming and stocking procedures in restoring acid lakes. The purpose of this paper is to provide an overview of LAMP and to summarize results from the initial phases of the project.

  11. The Effect of Inter-Implant Distance on Retention and Resistance to Dislodging Forces for Mandibular Implant-Tissue-Supported Overdentures

    PubMed Central

    Tabatabaian, Farhad; Saboury, Abolfazl; Sobhani, Zahra Sadat; Petropoulos, Vicki C

    2014-01-01

    Objectives: The effect of inter-implant distance on retention and resistance of implant-tissue-supported overdentures is lacking in the literature. An in vitro study was performed to evaluate this effect for mandibular implant-tissue-supported overdentures retained by two ball attachments. Materials and Methods: An acrylic cast of an edentulous mandible was fabricated. Three pairs of implants were symmetrically placed at both sides of the midline. The inter-implant distance was 10, 25, and 35 millimeters in positions A, B and C, respectively. A framework simulating the overdenture was fabricated on the cast. Six attachment housings were placed within the overdenture. For each sample, two ball abutments were screwed onto the implant pairs and two pink nylon inserts were seated in their respective attachment housings. The samples were tested in three groups of 15 (A, B, and C). The testing machine applied tensile dislodging forces and peak loads were measured in three directions: vertical, oblique, and anterior-posterior. A one-way ANOVA followed by Tukey’s HSD was used to determine groups that were significantly different. Tests were carried out at 0.05 level of significance. Results: Peak loads for the anterior-posteriorly directed dislodging forces were significantly the highest for group C (P<0.05); 21.25 N±3.05 N, while there were no statistically significant differences among groups with vertically and obliquely directed forces (P>0.05). Conclusion: Inter-implant distance did not affect the vertical retention and oblique resistance of mandibular implant-tissue-supported overdentures; however, it affected anterior-posterior resistance. PMID:25628676

  12. The effect of inter-implant distance on retention and resistance to dislodging forces for mandibular implant-tissue-supported overdentures.

    PubMed

    Tabatabaian, Farhad; Saboury, Abolfazl; Sobhani, Zahra Sadat; Petropoulos, Vicki C

    2014-09-01

    The effect of inter-implant distance on retention and resistance of implant-tissue-supported overdentures is lacking in the literature. An in vitro study was performed to evaluate this effect for mandibular implant-tissue-supported overdentures retained by two ball attachments. An acrylic cast of an edentulous mandible was fabricated. Three pairs of implants were symmetrically placed at both sides of the midline. The inter-implant distance was 10, 25, and 35 millimeters in positions A, B and C, respectively. A framework simulating the overdenture was fabricated on the cast. Six attachment housings were placed within the overdenture. For each sample, two ball abutments were screwed onto the implant pairs and two pink nylon inserts were seated in their respective attachment housings. The samples were tested in three groups of 15 (A, B, and C). The testing machine applied tensile dislodging forces and peak loads were measured in three directions: vertical, oblique, and anterior-posterior. A one-way ANOVA followed by Tukey's HSD was used to determine groups that were significantly different. Tests were carried out at 0.05 level of significance. Peak loads for the anterior-posteriorly directed dislodging forces were significantly the highest for group C (P<0.05); 21.25 N±3.05 N, while there were no statistically significant differences among groups with vertically and obliquely directed forces (P>0.05). Inter-implant distance did not affect the vertical retention and oblique resistance of mandibular implant-tissue-supported overdentures; however, it affected anterior-posterior resistance.

  13. Instability of Contact Resistance in MEMS and NEMS DC Switches under Low Force: the Role of Alien Films on the Contact Surface

    PubMed Central

    Qiu, Haodong; Wang, Hong; Ke, Feixiang

    2013-01-01

    The metal contact is one of the most crucial parts in ohmic-contact microelectromechanical (MEMS) switches, as it determines the device performance and reliability. It has been observed that there is contact instability when the contact force is below a threshold value (minimum contact force). However, there has been very limited knowledge so far about the unstable electrical contact behavior under low contact force. In this work, the instability of Au-Au micro/nano-contact behavior during the initial stage of contact formation is comprehensively investigated for the first time. It has been found that the alien film on the contact surface plays a critical role in determining the contact behavior at the initial contact stage under low contact force. A strong correlation between contact resistance fluctuation at the initial contact stage and the presence of a hydrocarbon alien film on the contact surface is revealed. The enhancement of contact instability due to the alien film can be explained within a framework of trap-assisted tunneling.

  14. Strength training at high versus low external resistance in older adults: effects on muscle volume, muscle strength, and force-velocity characteristics.

    PubMed

    Van Roie, Evelien; Delecluse, Christophe; Coudyzer, Walter; Boonen, Steven; Bautmans, Ivan

    2013-11-01

    Muscle adaptations can be induced by high-resistance exercise. Despite being potentially more suitable for older adults, low-resistance exercise protocols have been less investigated. We compared the effects of high- and low-resistance training on muscle volume, muscle strength, and force-velocity characteristics. Fifty-six older adults were randomly assigned to 12 weeks of leg press and leg extension training at either HIGH (2×10-15 repetitions at 80% of one repetition maximum (1RM)), LOW (1×80-100 repetitions at 20% of 1RM), or LOW+ (1×60 repetitions at 20% of 1RM, followed by 1×10-20 repetitions at 40% of 1RM). All protocols ended with muscle failure. Leg press and leg extension of 1RM were measured at baseline and post intervention and before the first training session in weeks 5 and 9. At baseline and post intervention, muscle volume (MV) was measured by CT-scan. A Biodex dynamometer evaluated knee extensor static peak torque in different knee angles (PT(stat90°), PT(stat120°), PT(stat150°)), dynamic peak torque at different speeds (PT(dyn60°s)(-1), PT(dyn180°s)(-1), PT(dyn240°s)(-1)), and speed of movement at 20% (S20), 40% (S40), and 60% (S60) of PTstat90°. HIGH and LOW+ resulted in greater improvements in 1RM strength than LOW (p<0.05). These differences were already apparent after week 5. Similar gains were found between groups in MV, PT(stat), PT(dyn60°s)(-1), and PT(dyn180°s)(-1). No changes were reported in speed of movement. HIGH tended to improve PT(dyn240°s)(-1) more than LOW or LOW+ (p=0.064). In conclusion, high- and low-resistance exercises ending with muscle failure may be similarly effective for hypertrophy. High-resistance training led to a higher increase in 1RM strength than low-resistance training (20% of 1RM), but this difference disappeared when using a mixed low-resistance protocol in which the resistance was intensified within a single exercise set (40% of 1RM). Our findings support the need for more research on low-resistance

  15. Adaptive magnetorheological seat suspension for shock mitigation

    NASA Astrophysics Data System (ADS)

    Singh, Harinder J.; Wereley, Norman M.

    2013-04-01

    An adaptive magnetorheological seat suspension (AMSS) was analyzed for optimal protection of occupants from shock loads caused by the impact of a helicopter with the ground. The AMSS system consists of an adaptive linear stroke magnetorheological shock absorber (MRSA) integrated into the seat structure of a helicopter. The MRSA provides a large controllability yield force to accommodate a wide spectrum for shock mitigation. A multiple degrees-of-freedom nonlinear biodynamic model for a 50th percentile male occupant was integrated with the dynamics of MRSA and the governing equations of motion were investigated theoretically. The load-stroke profile of MRSA was optimized with the goal of minimizing the potential for injuries. The MRSA yield force and the shock absorber stroke limitations were the most crucial parameters for improved biodynamic response mitigation. An assessment of injuries based on established injury criteria for different body parts was carried out.

  16. Platelet Composite Coatings for Tin Whisker Mitigation

    NASA Astrophysics Data System (ADS)

    Rohwer, Lauren E. S.; Martin, James E.

    2015-11-01

    Reliable methods for tin whisker mitigation are needed for applications that utilize tin-plated commercial components. Tin can grow whiskers that can lead to electrical shorting, possibly causing critical systems to fail catastrophically. The mechanisms of tin whisker growth are unclear and this makes prediction of the lifetimes of critical components uncertain. The development of robust methods for tin whisker mitigation is currently the best approach to eliminating the risk of shorting. Current mitigation methods are based on unfilled polymer coatings that are not impenetrable to tin whiskers. In this paper we report tin whisker mitigation results for several filled polymer coatings. The whisker-penetration resistance of the coatings was evaluated at elevated temperature and high humidity and under temperature cycling conditions. The composite coatings comprised Ni and MgF2-coated Al/Ni/Al platelets in epoxy resin or silicone rubber. In addition to improved whisker mitigation, these platelet composites have enhanced thermal conductivity and dielectric constant compared with unfilled polymers.

  17. Platelet composite coatings for tin whisker mitigation

    SciTech Connect

    Rohwer, Lauren E. S.; Martin, James E.

    2015-09-14

    In this study, reliable methods for tin whisker mitigation are needed for applications that utilize tin-plated commercial components. Tin can grow whiskers that can lead to electrical shorting, possibly causing critical systems to fail catastrophically. The mechanisms of tin whisker growth are unclear and this makes prediction of the lifetimes of critical components uncertain. The development of robust methods for tin whisker mitigation is currently the best approach to eliminating the risk of shorting. Current mitigation methods are based on unfilled polymer coatings that are not impenetrable to tin whiskers. In this paper we report tin whisker mitigation results for several filled polymer coatings. The whisker-penetration resistance of the coatings was evaluated at elevated temperature and high humidity and under temperature cycling conditions. The composite coatings comprised Ni and MgF2-coated Al/Ni/Al platelets in epoxy resin or silicone rubber. In addition to improved whisker mitigation, these platelet composites have enhanced thermal conductivity and dielectric constant compared with unfilled polymers.

  18. Platelet composite coatings for tin whisker mitigation

    DOE PAGES

    Rohwer, Lauren E. S.; Martin, James E.

    2015-09-14

    In this study, reliable methods for tin whisker mitigation are needed for applications that utilize tin-plated commercial components. Tin can grow whiskers that can lead to electrical shorting, possibly causing critical systems to fail catastrophically. The mechanisms of tin whisker growth are unclear and this makes prediction of the lifetimes of critical components uncertain. The development of robust methods for tin whisker mitigation is currently the best approach to eliminating the risk of shorting. Current mitigation methods are based on unfilled polymer coatings that are not impenetrable to tin whiskers. In this paper we report tin whisker mitigation results formore » several filled polymer coatings. The whisker-penetration resistance of the coatings was evaluated at elevated temperature and high humidity and under temperature cycling conditions. The composite coatings comprised Ni and MgF2-coated Al/Ni/Al platelets in epoxy resin or silicone rubber. In addition to improved whisker mitigation, these platelet composites have enhanced thermal conductivity and dielectric constant compared with unfilled polymers.« less

  19. Wetlands Mitigation Banking Concepts

    DTIC Science & Technology

    1992-07-01

    the financial risk associated with are normally established in advance, mitigation permitted activities. banks eliminate the lag time between loss and...management natural state or to an enhanced condition and techniques. None of the traditional wetlands begin to amass bankable credits has also been management

  20. Space Debris Mitigation Guidelines

    NASA Technical Reports Server (NTRS)

    Johnson, Nicholas L.

    2011-01-01

    The purpose of national and international space debris mitigation guides is to promote the preservation of near-Earth space for applications and exploration missions far into the future. To accomplish this objective, the accumulation of objects, particularly in long-lived orbits, must be eliminated or curtailed.

  1. Teaching Hazards Mitigation.

    ERIC Educational Resources Information Center

    Abernethy, James

    1980-01-01

    It is recommended that courses be provided for architectural students in postoccupancy building performance and user experience. A course in disaster mitigation is described. It was introduced to increase student awareness of the importance of design decisions in building safety. (MSE)

  2. Efficacy of a trunk orthosis with joints providing resistive force on low-back load in elderly persons during static standing.

    PubMed

    Katsuhira, Junji; Matsudaira, Ko; Yasui, Tadashi; Iijima, Shinno; Ito, Akihiro

    2015-01-01

    Postural alignment of elderly people becomes poor due to aging, possibly leading to low-back pain and spinal deformity. Although there are several interventions for treating these conditions, no previous study has reported the effectiveness of a spinal orthosis or lumbosacral orthosis (LSO) in healthy elderly people without specific spinal deformity. We therefore developed a trunk orthosis to decrease low-back muscle activity while training good postural alignment through resistive force provided by joints with springs (here, called the ORF, which stands for orthosis with joints providing resistive force) as a preventive method against abnormal posture and low-back pain in healthy elderly persons. Fifteen community-dwelling elderly men participated in this study. Participants stood freely for 10 seconds in a laboratory setting under three conditions: without an orthosis, with the ORF, and with an LSO. The Damen corset LSO was selected as it is frequently prescribed for patients with low-back pain. Postural alignment during static standing was recorded using a three-dimensional motion capture system employing infrared cameras. Two force plates were used to record center of pressure. Electromyograms were obtained for bilateral erector spinae (ES), left internal abdominal oblique, and right gluteus medius muscles. Pelvis forward tilt angle tended to increase while wearing the ORF and decrease while wearing the LSO, but these results were not significant compared to no orthosis. Thorax extension angle and thorax angle on pelvis coordinate system significantly increased while wearing the ORF compared to the other two conditions. ES activity significantly decreased while wearing the ORF compared to the other two conditions. Internal oblique activity was significantly smaller while wearing the LSO than with no orthosis. Center of pressure did not significantly differ among the conditions. The ORF significantly improved trunk alignment and decreased ES activity in healthy

  3. Efficacy of a trunk orthosis with joints providing resistive force on low-back load in elderly persons during static standing

    PubMed Central

    Katsuhira, Junji; Matsudaira, Ko; Yasui, Tadashi; Iijima, Shinno; Ito, Akihiro

    2015-01-01

    Purpose Postural alignment of elderly people becomes poor due to aging, possibly leading to low-back pain and spinal deformity. Although there are several interventions for treating these conditions, no previous study has reported the effectiveness of a spinal orthosis or lumbosacral orthosis (LSO) in healthy elderly people without specific spinal deformity. We therefore developed a trunk orthosis to decrease low-back muscle activity while training good postural alignment through resistive force provided by joints with springs (here, called the ORF, which stands for orthosis with joints providing resistive force) as a preventive method against abnormal posture and low-back pain in healthy elderly persons. Patients and methods Fifteen community-dwelling elderly men participated in this study. Participants stood freely for 10 seconds in a laboratory setting under three conditions: without an orthosis, with the ORF, and with an LSO. The Damen corset LSO was selected as it is frequently prescribed for patients with low-back pain. Postural alignment during static standing was recorded using a three-dimensional motion capture system employing infrared cameras. Two force plates were used to record center of pressure. Electromyograms were obtained for bilateral erector spinae (ES), left internal abdominal oblique, and right gluteus medius muscles. Results Pelvis forward tilt angle tended to increase while wearing the ORF and decrease while wearing the LSO, but these results were not significant compared to no orthosis. Thorax extension angle and thorax angle on pelvis coordinate system significantly increased while wearing the ORF compared to the other two conditions. ES activity significantly decreased while wearing the ORF compared to the other two conditions. Internal oblique activity was significantly smaller while wearing the LSO than with no orthosis. Center of pressure did not significantly differ among the conditions. Conclusion The ORF significantly improved trunk

  4. Surface potential and resistance measurements for detecting wear of chemically-bonded and unbonded molecularly-thick perfluoropolyether lubricant films using atomic force microscopy.

    PubMed

    Palacio, Manuel; Bhushan, Bharat

    2007-11-01

    The wear of perfluoropolyether (PFPE) lubricants applied on Si(100) and an Au film on Si(100) substrate at ultralow loads was investigated by using atomic force microscopy (AFM)-based surface potential and resistance measurements. Surface potential data is used in detecting lubricant removal and the initiation of wear on the silicon substrate. The surface potential change is attributed to the change in the work function of the silicon after wear, and electrostatic charge build-up of debris in the lubricant. It was found that coatings that are partially bonded, i.e., containing a mobile lubricant fraction, were better able to protect the silicon substrate from wear compared to the fully bonded coating. This enhanced protection is attributed to a lubricant replenishment mechanism. However, an untreated lubricant coating exhibited considerable wear as it contains a smaller amount of lubricant bonded to the substrate relative to the partially bonded and fully bonded coatings. A sample subjected to shear is shown to have improved wear resistance, and this enhancement is attributed to chain reorientation and alignment of the lubricant molecules. The detection of wear of PFPE lubricants on Au by an AFM-based resistance measurement method is demonstrated for the first time. This technique provides complementary information to surface potential data in detecting substrate exposure after wear and is a promising method for studying the wear of conducting films.

  5. IAP National Task Force for Childhood Prevention of Adult Diseases: insulin resistance and Type 2 diabetes mellitus in childhood.

    PubMed

    Bhatia, Vijayalakshmi

    2004-05-01

    Type 2 diabetes mellitus (DM) has traditionally been considered a disease of adults. However, in the last 2 decades, it is increasingly being reported in children and adolescents. Obesity is a strong correlate, and the increasing prevalence of obesity and poor physical activity is precipitating type 2 DM at younger ages in the ethnic groups at risk. Indians and other South Asians are among the ethnic groups particularly prone to insulin resistance and type 2 DM, the other racial groups being some American Indian tribes like the Pima Indians, Mexican Americans,Pacific Islanders and African Americans,among others. The WHO has predicted that India will have the greatest number of diabetic individuals in the world by the year 2025. Type 2 DM starting during adolescence puts the individual at risk for major morbidity and even mortality right during the productive years of life. The microvascular complications of DM (nephropathy, retinopathy, neuropathy) are brought on at an early age. In addition, type 2 DM and obesity are two components of a metabolic syndrome of insulin resistance, the other features of which include hypertension, dyslipidemia and hypercoagulability of blood. All these conditions together increase the risk for cardiovascular and cerebrovascular mortality and morbidity (i.e., myocardial infarction and stroke). The resulting economic burden will be enormous. Type 2 DM and the insulin resistance syndrome are to a large extent preventable. Adoption of a healthy eating and physical activity pattern has resulted in decreasing the development of DM in a few recent studies from various parts of the world. A concerted,multi-pronged effort is needed, involving the general public, pediatricians and general physicians, teachers and schools, the media,the government and professional medical bodies, to generate a momentum towards the goal of prevention of type 2 DM and the insulin resistance syndrome in the young population of India.

  6. The Effects of Reduced Atmospheric Pressure on Thermal Contact Resistance and Electronic Component Forced Air Film Coefficients

    DTIC Science & Technology

    1980-08-15

    two parallel flat plates with an intersticial uniform air gap. Rearranging terms for thermal resistance, this relationship is as follows: = + 4I Xm 2...gap ranging from 0.0005" to 0.003" between itself and an aluminum card guide and where the intersticial air is at 50°C, it is a relatively simple...correlations were carried out over a wide range of variables including contact materials, intersticial fluids, surface finishes and roughnesses, contact

  7. The mitigation of interpersonal behavior.

    PubMed

    Fournier, M A; Moskowitz, D S

    2000-11-01

    Theorists since D. Bakan (1966) have advocated the importance of mitigation for successful adaptation within the interpersonal domain. Although mitigation has previously been conceptualized as a balance between agency and communion (interdimensional mitigation), the circumplex framework suggests that mitigation may also be conceptualized as a balance within agency and a balance within communion (intradimensional mitigation). In the two present studies, participants collected records of their interpersonal behavior and affect subsequent to their social interactions for a period of 20 days. Random coefficient procedures were then used to examine these two contrasting models of mitigation in the prediction of affect. No empirical evidence of interdimensional mitigation was found. The findings suggest that agency and communion were each mitigated intradimensionally through moderate levels of behavioral expression.

  8. The effects of 10 weeks of resistance training combined with beta-alanine supplementation on whole body strength, force production, muscular endurance and body composition.

    PubMed

    Kendrick, Iain P; Harris, Roger C; Kim, Hyo Jeong; Kim, Chang Keun; Dang, Viet H; Lam, Thanh Q; Bui, Toai T; Smith, Marcus; Wise, John A

    2008-05-01

    Carnosine (Carn) occurs in high concentrations in skeletal muscle is a potent physico-chemical buffer of H+ over the physiological range. Recent research has demonstrated that 6.4 g x day(-1) of beta-alanine (beta-ala) can significantly increase skeletal muscle Carn concentrations (M-[Carn]) whilst the resultant change in buffering capacity has been shown to be paralleled by significant improvements in anaerobic and aerobic measures of exercise performance. Muscle carnosine increase has also been linked to increased work done during resistance training. Prior research has suggested that strength training may also increase M-[Carn] although this is disputed by other studies. The aim of this investigation is to assess the effect of 10 weeks resistance training on M-[Carn], and, secondly, to investigate if increased M-[Carn] brought about through beta-ala supplementation had a positive effect on training responses. Twenty-six Vietnamese sports science students completed the study. The subjects completed a 10-week resistance-training program whilst consuming 6.4 g x day(-1) of beta-ala (beta-ALG) or a matched dose of a placebo (PLG). Subjects were assessed prior to and after training for whole body strength, isokinetic force production, muscular endurance, body composition. beta-Alanine supplemented subjects increased M-[Carn] by 12.81 +/- 7.97 mmol x kg(-1) dry muscle whilst there was no change in PLG subjects. There was no significant effect of beta-ala supplementation on any of the exercise parameters measured, mass or % body fat. In conclusion, 10 weeks of resistance training alone did not change M-[Carn].

  9. Mitigating Infectious Disease Outbreaks

    NASA Astrophysics Data System (ADS)

    Davey, Victoria

    The emergence of new, transmissible infections poses a significant threat to human populations. As the 2009 novel influenza A/H1N1 pandemic and the 2014-2015 Ebola epidemic demonstrate, we have observed the effects of rapid spread of illness in non-immune populations and experienced disturbing uncertainty about future potential for human suffering and societal disruption. Clinical and epidemiologic characteristics of a newly emerged infectious organism are usually gathered in retrospect as the outbreak evolves and affects populations. Knowledge of potential effects of outbreaks and epidemics and most importantly, mitigation at community, regional, national and global levels is needed to inform policy that will prepare and protect people. Study of possible outcomes of evolving epidemics and application of mitigation strategies is not possible in observational or experimental research designs, but computational modeling allows conduct of `virtual' experiments. Results of well-designed computer simulations can aid in the selection and implementation of strategies that limit illness and death, and maintain systems of healthcare and other critical resources that are vital to public protection. Mitigating Infectious Disease Outbreaks.

  10. Ground Reaction Force and Mechanical Differences Between the Interim Resistive Exercise Device (iRED) and Smith Machine While Performing a Squat

    NASA Technical Reports Server (NTRS)

    Amonette, William E.; Bentley, Jason R.; Lee, Stuart M. C.; Loehr, James A.; Schneider, Suzanne

    2004-01-01

    Musculoskeletal unloading in microgravity has been shown to induce losses in bone mineral density, muscle cross-sectional area, and muscle strength. Currently, an Interim Resistive Exercise Device (iRED) is being flown on board the ISS to help counteract these losses. Free weight training has shown successful positive musculoskeletal adaptations. In biomechanical research, ground reaction forces (GRF) trajectories are used to define differences between exercise devices. The purpose of this evaluation is to quantify the differences in GRF between the iRED and free weight exercise performed on a Smith machine during a squat. Due to the differences in resistance properties, inertial loading and load application to the body between the two devices, we hypothesize that subjects using iRED will produce GRF that are significantly different from the Smith machine. There will be differences in bar/harness range of motion and the time when peak GRF occurred in the ROMbar. Three male subjects performed three sets of ten squats on the iRED and on the Smith Machine on two separate days at a 2-second cadence. Statistically significant differences were found between the two devices in all measured GRF variables. Average Fz and Fx during the Smith machine squat were significantly higher than iRED. Average Fy (16.82 plus or minus.23; p less than .043) was significantly lower during the Smith machine squat. The mean descent/ascent ratio of the magnitude of the resultant force vector of all three axes for the Smith machine and iRED was 0.95 and 0.72, respectively. Also, the point at which maximum Fz occurred in the range of motion (Dzpeak) was at different locations with the two devices.

  11. The influence of wind resistance in running and walking and the mechanical efficiency of work against horizontal or vertical forces

    PubMed Central

    Pugh, L. G. C. E.

    1971-01-01

    1. O2 intakes were determined on subjects running and walking at various constant speeds, (a) against wind of up to 18·5 m/sec (37 knots) in velocity, and (b) on gradients ranging from 2 to 8%. 2. In running and walking against wind, O2 intakes increased as the square of wind velocity. 3. In running on gradients the relation of O2 intake and lifting work was linear and independent of speed. In walking on gradients the relation was linear at work rates above 300 kg m/min, but curvilinear at lower work rates. 4. In a 65 kg athlete running at 4·45 m/sec (marathon speed) V̇O2 increased from 3·0 l./min with minimal wind to 5·0 l./min at a wind velocity of 18·5 m/sec. The corresponding values for a 75 kg subject walking at 1·25 m/sec were 0·8 l./min with minimal wind and 3·1 l./min at a wind velocity of 18·5 m/sec. 5. Direct measurements of wind pressure on shapes of similar area to one of the subjects yielded higher values than those predicted from the relation of wind velocity and lifting work at equal O2 intakes. Horizontal work against wind was more efficient than vertical work against gravity. 6. The energy cost of overcoming air resistance in track running may be 7·5% of the total energy cost at middle distance speed and 13% at sprint speed. Running 1 m behind another runner virtually eliminated air resistance and reduced V̇O2 by 6·5% at middle distance speed. PMID:5574828

  12. Comparative genomic analysis of Staphylococcus aureus FORC_001 and S. aureus MRSA252 reveals the characteristics of antibiotic resistance and virulence factors for human infection.

    PubMed

    Lim, Sooyeon; Lee, Dong-Hoon; Kwak, Woori; Shin, Hakdong; Ku, Hye-Jin; Lee, Jong-Eun; Lee, Gun Eui; Kim, Heebal; Choi, Sang-Ho; Ryu, Sangryeol; Lee, Ju-Hoon

    2015-01-01

    Staphylococcus aureus is an important foodborne pathogen that causes diverse diseases ranging from minor infections to life-threatening conditions in humans and animals. To further understand its pathogenesis, the genome of the strain S. aureus FORC_001 was isolated from a contaminated food. Its genome consists of 2,886,017 bp double-stranded DNA with a GC content of 32.8%. It is predicted to contain 2,728 open reading frames, 57 tRNAs, and 6 rRNA operons, including 1 additional 5S rRNA gene. Comparative phylogenetic tree analysis of 40 complete S. aureus genome sequences using average nucleotide identity (ANI) revealed that strain FORC_001 belonged to Group I. The closest phylogenetic match was S. aureus MRSA252, according to a whole-genome ANI (99.87%), suggesting that they might share a common ancestor. Comparative genome analysis of FORC_001 and MRSA252 revealed two non-homologous regions: Regions I and II. The presence of various antibiotic resistance genes, including the SCCmec cluster in Region I of MRSA252, suggests that this strain might have acquired the SCCmec cluster to adapt to specific environments containing methicillin. Region II of both genomes contains prophage regions but their DNA sequence identity is very low, suggesting that the prophages might differ. This is the first report of the complete genome sequence of S. aureus isolated from a real foodborne outbreak in South Korea. This report would be helpful to extend our understanding about the genome, general characteristics, and virulence factors of S. aureus for further studies of pathogenesis, rapid detection, and epidemiological investigation in foodborne outbreak.

  13. Impact of lateral force-resisting system and design/construction practices on seismic performance and cost of tall buildings in Dubai, UAE

    NASA Astrophysics Data System (ADS)

    AlHamaydeh, Mohammad; Galal, Khaled; Yehia, Sherif

    2013-09-01

    The local design and construction practices in the United Arab Emirates (UAE), together with Dubai's unique rate of development, warrant special attention to the selection of Lateral Force-Resisting Systems (LFRS). This research proposes four different feasible solutions for the selection of the LFRS for tall buildings and quantifies the impact of these selections on seismic performance and cost. The systems considered are: Steel Special Moment-Resisting Frame (SMRF), Concrete SMRF, Steel Dual System (SMRF with Special Steel Plates Shear Wall, SPSW), and Concrete Dual System (SMRF with Special Concrete Shear Wall, SCSW). The LFRS selection is driven by seismic setup as well as the adopted design and construction practices in Dubai. It is found that the concrete design alternatives are consistently less expensive than their steel counterparts. The steel dual system is expected to have the least damage based on its relatively lesser interstory drifts. However, this preferred performance comes at a higher initial construction cost. Conversely, the steel SMRF system is expected to have the most damage and associated repair cost due to its excessive flexibility. The two concrete alternatives are expected to have relatively moderate damage and repair costs in addition to their lesser initial construction cost.

  14. Electronic Force Gage for Welders

    NASA Technical Reports Server (NTRS)

    Bradley, J. W.; Gates, G.

    1983-01-01

    Welding force monitored in process. Electronic force gage uses strain gage on deformable member. Oscilloscope trace of welding force photographed and compared with standard trace during calibration and troubleshooting of resistance welding equipment. Adaptable to small scale resistance welding in electronics industry.

  15. Mitigating flood exposure

    PubMed Central

    Shultz, James M; McLean, Andrew; Herberman Mash, Holly B; Rosen, Alexa; Kelly, Fiona; Solo-Gabriele, Helena M; Youngs Jr, Georgia A; Jensen, Jessica; Bernal, Oscar; Neria, Yuval

    2013-01-01

    Introduction. In 2011, following heavy winter snowfall, two cities bordering two rivers in North Dakota, USA faced major flood threats. Flooding was foreseeable and predictable although the extent of risk was uncertain. One community, Fargo, situated in a shallow river basin, successfully mitigated and prevented flooding. For the other community, Minot, located in a deep river valley, prevention was not possible and downtown businesses and one-quarter of the homes were inundated, in the city’s worst flood on record. We aimed at contrasting the respective hazards, vulnerabilities, stressors, psychological risk factors, psychosocial consequences, and disaster risk reduction strategies under conditions where flood prevention was, and was not, possible. Methods. We applied the “trauma signature analysis” (TSIG) approach to compare the hazard profiles, identify salient disaster stressors, document the key components of disaster risk reduction response, and examine indicators of community resilience. Results. Two demographically-comparable communities, Fargo and Minot, faced challenging river flood threats and exhibited effective coordination across community sectors. We examined the implementation of disaster risk reduction strategies in situations where coordinated citizen action was able to prevent disaster impact (hazard avoidance) compared to the more common scenario when unpreventable disaster strikes, causing destruction, harm, and distress. Across a range of indicators, it is clear that successful mitigation diminishes both physical and psychological impact, thereby reducing the trauma signature of the event. Conclusion. In contrast to experience of historic flooding in Minot, the city of Fargo succeeded in reducing the trauma signature by way of reducing risk through mitigation. PMID:28228985

  16. Forced extinction of CD24 stem-like breast cancer marker alone promotes radiation resistance through the control of oxidative stress.

    PubMed

    Bensimon, Julie; Biard, Denis; Paget, Vincent; Goislard, Maud; Morel-Altmeyer, Sandrine; Konge, Julie; Chevillard, Sylvie; Lebeau, Jérôme

    2016-03-01

    Along with CD44, CD24 is a key marker of breast cancer stem cells (CSCs), frequently defined by CD24(-)/CD44(+) labeling. Among all phenotypes classically attributed to breast CD24(-)/CD44(+) cancer cells, radiation resistance has been extensively described and seen as being implicated in radiotherapy failure. Our previous data indicated that CD24(-) cells constitute a radiation-resistant subpopulation transitory selected by high doses of ionizing radiation. However, little is known about the biological role of CD24 in breast cancers, and no function has been assigned to CD24 in radiation response. Here, CD24 expression was induced in CD24(-) cells or knocked-down in CD24(+) cells. We show that forced extinction of CD24 expression is associated with decreased proliferation rate, lower levels of reactive oxygen species (ROS) and decreased genomic instability. On the opposite when CD24 is artificially expressed in CD24(-) cells, proliferation rates in vitro and in vivo, ROS levels and genomic instability are enhanced. Moreover, we observe that loss of CD24 expression leads to radiation resistance, by preventing radiation-induced cell death and promoting generation of progeny in relation to lower G2/M blockade and a smaller proportion of polyploid cells. Finally, control of ROS levels appears to be the key event in the CD24-mediated radiation response. For the first time, CD24 is proposed as a direct actor in radiation response of breast cancer cells, independently of CD44 expression. These findings could have interesting applications in evaluating the intrinsic radiation response of primary tumors.

  17. Zebra mussel mitigation; overview

    SciTech Connect

    Claudi, R.

    1995-06-01

    Zebra mussels cause a number of problems to industrial raw water users as well as having serious impact on civil structures exposed to mussel infested waters. The largest volume of water (up to 90% of the total) drawn into most industrial and power generating plants, is for cooling and heat transfer. The rest of the volume is used for other plant processes, such as make-up in steam systems, and service systems used for cleaning, air conditions, fire protection and human consumption. All raw water systems are vulnerable to zebra mussel infestation to greater or lesser degree. To-date, many different chemical and non-chemical techniques for zebra mussel control have been investigated. However, the treatment of choice for most facilities is based on chemical control. This has been the common practice in Europe and so far it has been the case in North America. This is likely to change as the environmental constraints on release of chemicals into natural water bodies continue to increase. This paper deals with the different steps raw water users should take when deciding on a mitigation strategy, the mitigation measures available to-date and those that have been proposed for the control of zebra mussels in industrial systems.

  18. RFI Mitigation / Excision techniques

    NASA Astrophysics Data System (ADS)

    Roshi, D. A.

    2004-06-01

    Radio frequency interference (RFI) is increasingly affecting radio astronomy research. A few years ago, active research to investigate the possibility of observing in the presence of interference using RFI mitigation techniques was initiated. In this paper, I briefly discuss four RFI mitigation/excision projects. These projects are:- (1) A technique to suppress double sideband amplitude modulated interference in which I show that an astronomical signal in the presence of a DSB interference can be observed with a signal-to-noise ratio factor of 2 less compared to observations if the RFI were not present. (2) Techniques to suppress interference due to synchronization signals in composite video signals are presented. A combination of noise-free modelling of the synchronization signals and adaptive filtering is used for suppressing the interference. (3) Design techniques to minimize spurious pick-up at the analog input of an analog-to-digital converter are discussed. (4) Spectral RFI excision using a spectral channel weighted scheme and its application to Green Bank telescope observations are also presented.

  19. The anterior cruciate ligament provides resistance to externally applied anterior tibial force but not to internal rotational torque during simulated weight-bearing flexion.

    PubMed

    Wünschel, Markus; Müller, Otto; Lo, JiaHsuan; Obloh, Christian; Wülker, Nikolaus

    2010-11-01

    We investigated knee kinematics during simulated weight-bearing flexion and determined the effect of 3 different parameters of external tibial loading on the kinematics of the anterior cruciate ligament (ACL)-intact and ACL-deficient knee. Ten human knee specimens were mounted on a dynamic knee simulator, and weight-bearing muscle-loaded knee flexions were simulated while a robotic/universal force sensor system was used to provide external tibial loads during the motion. Three different loading conditions were simulated: partial body weight only, an additional 50 N of anterior tibial force (ATD), or an additional 5 Nm of internal rotational tibial torque (IRT). After arthroscopic transection of the ACL, these 3 trials were repeated. The kinematics were measured with an ultrasonic measuring system for 3-dimensional motion analysis, and different loading and knee conditions were examined. When the ACL was intact, ATD and IRT barely changed the anterior tibial translation. However, in the absence of the ACL, ATD significantly increased the anterior tibial translation by 5 mm whereas IRT did not. The application of IRT increased the internal tibial rotation of ACL-intact knees, but there was no difference in the internal rotation before and after transection of the ACL. Regardless of ACL status, the difference in the anterior tibial translation and the internal tibial rotation across different external tibial loadings was greater at lower flexion angles and gradually diminished with increasing flexion angles. We established an experimental protocol, incorporating a dynamic knee simulator and a robotic/universal force sensor system, to successfully measure the kinematics of the knee joint while applying external forces in weight-bearing flexion. Our findings suggest that, in muscle-loaded knee flexion, the ACL provides substantial resistance to externally applied ATD but not to IRT. Information from this study allows us to better understand the function of the ACL and

  20. National Standard of the Russian Federation for Space Debris Mitigation

    NASA Astrophysics Data System (ADS)

    Loginov, S.; Yakovlev, M.; Mikhailov, M.; Popkova, L.

    2009-03-01

    Normative and technical document that define requirements for the mitigation of human-produced near-earth space pollution develops in Russian Federation.NATIONAL STANDARD of the Russian Federation GOST R 52925-2008 «SPACE TECHNOLOGY ITEMS. General Requirements on Space Systems for the Mitigation of Human-Produced near-Earth Space Pollution» was approved in 2008 and entered into force since 1st January of 2009. Requirements of this standard harmonized with requirements of «UN SPACE DEBRIS MITIGATION GUIDELINESÈ»This standard consists of six parts:- Scope;- References to Standards;- Terms & Definitions;- Abbreviations;- General Provisions;- General Requirements on Space Systems for the Mitigation of Human-Produced near-Earth Space Pollution.

  1. Experimental Investigation of Passive Shock Wave Mitigation using Obstacle Arrangements

    NASA Astrophysics Data System (ADS)

    Nguyen, Monica; Wan, Qian; Eliasson, Veronica

    2014-11-01

    With its vast range in applications, especially in the defense industry, shock wave mitigation is an ongoing research area of interest to the shock dynamics community. Passive shock wave mitigation methods range from forcing the shock wave to abruptly change its direction to introducing barriers or obstacles of various shapes and materials in the path of the shock wave. Obstacles provide attenuation through complicated shock wave interactions and reflections. In this work, we have performed shock tube experiments to investigate shock wave mitigation due to solid obstacles placed along the curve of a logarithmic spiral. Different shapes (cylindrical and square) of obstacles with different materials (solid and foam) have been used. High-speed schlieren optics and background-oriented schlieren techniques have been used together with pressure measurements to quantify the effects of mitigation. Results have also been compared to numerical simulations and show good agreement.

  2. Receptive females mitigate costs of sexual conflict.

    PubMed

    Harano, T

    2015-02-01

    Males typically gain fitness from multiple mating, whereas females often lose fitness from numerous mating, potentially leading to sexual conflict over mating. This conflict is expected to favour the evolution of female resistance to mating. However, females may incur male harassment if they refuse to copulate; thus, greater female resistance may increase costs imposed by males. Here, I show that the evolution of resistance to mating raises fitness disadvantages of interacting with males when mating is harmful in female adzuki bean beetles, Callosobruchus chinensis. Females that were artificially selected for higher and lower remating propensity evolved to accept and resist remating, respectively. Compared with females that evolved to accept remating, females that evolved to resist it suffered higher fitness costs from continuous exposure to males. The costs of a single mating measured by the effect on longevity did not differ among selection line females. This study indicates that receptive rather than resistant females mitigate the fitness loss resulting from sexual conflict, suggesting that even though mating is harmful, females can evolve to accept additional mating.

  3. Novel Ice Mitigation Methods

    NASA Technical Reports Server (NTRS)

    2008-01-01

    After the loss of Columbia, there was great concern in the Space Shuttle program for the impact of debris against the leading edges of the Orbiter wings. It was quickly recognized that, in addition to impacts by foam, ice that formed on the liquid-oxygen bellows running down the outside of the External Tank could break free during launch and hit this sensitive area. A Center Director s Discretionary Fund (CDDF) project would concentrate on novel ideas that were potentially applicable. The most successful of the new concepts for ice mitigation involved shape memory alloy materials. These materials can be bent into a given shape and, when heated, will return to their original shape.

  4. Climate change and mitigation.

    PubMed

    Nibleus, Kerstin; Lundin, Rickard

    2010-01-01

    Planet Earth has experienced repeated changes of its climate throughout time. Periods warmer than today as well as much colder, during glacial episodes, have alternated. In our time, rapid population growth with increased demand for natural resources and energy, has made society increasingly vulnerable to environmental changes, both natural and those caused by man; human activity is clearly affecting the radiation balance of the Earth. In the session "Climate Change and Mitigation" the speakers offered four different views on coal and CO2: the basis for life, but also a major hazard with impact on Earth's climate. A common denominator in the presentations was that more than ever science and technology is required. We need not only understand the mechanisms for climate change and climate variability, we also need to identify means to remedy the anthropogenic influence on Earth's climate.

  5. Optimal Design of Honeycomb Material Used to Mitigate Head Impact

    PubMed Central

    Caccese, Vincent; Ferguson, James R.; Edgecomb, Michael

    2013-01-01

    This paper presents a study of the impact resistance of honeycomb structure with the purpose to mitigate impact forces. The objective is to aid in the choice of optimal parameters to minimize the thickness of the honeycomb structure while providing adequate protection to prevent injury due to head impact. Studies are presented using explicit finite element analysis representing the case of an unprotected drop of a rigid impactor onto a simulated floor consisting of vinyl composition tile and concrete. Analysis of honeycomb material to reduce resulting accelerations is also presented where parameters such as honeycomb material modulus, wall thickness, cell geometry and structure depth are compared to the unprotected case. A simplified analysis technique using a genetic algorithm is presented to demonstrate the use of this method to select a minimum honeycomb depth to achieve a desired acceleration level at a given level of input energy. It is important to select a minimum material depth in that smaller dimensions lead toward more aesthetic design that increase the likelihood of that the device is used. PMID:23976812

  6. Resistance to the development of stress-induced behavioral despair in the forced swim test associated with elevated hippocampal Bcl-xl expression.

    PubMed

    Shishkina, Galina T; Kalinina, Tatyana S; Berezova, Inna V; Bulygina, Veta V; Dygalo, Nikolay N

    2010-12-01

    Stress may predispose individuals toward depression through down-regulation of neurogenesis and increase in apoptosis in the brain. However, many subjects show high resistance to stress in relation to psychopathology. In the present study, we assessed the possibility that individual-specific patterns of gene expression associated with cell survival and proliferation may be among the molecular factors underlying stress resilience. Brain-derived neurotrophic factor (BDNF), anti-apoptotic B cell lymphoma like X (Bcl-xl) and pro-apoptotic bcl2-associated X protein (Bax) expression were determined in the hippocampus and frontal cortex of rats naturally differed in despair-like behavior in the forced swim test. In the hippocampus, BDNF messenger RNA (mRNA) level was significantly down-regulated 2h after the forced swim test exposure, and at this time point, Bcl-xl mRNA and protein levels were significantly higher in stressed than in untested animals. The ratios of hippocampal Bcl-xl to Bax mRNA negatively correlated with the total time spent immobile in the test. When animals were divided in two groups according to immobility responses in two consecutive swim sessions and designated as stress resilient if their immobility time did not increase in the second session as it did in stress sensitive rats, it was found that resilient rats had significantly higher Bcl-xl/Bax ratios in the hippocampus than stress sensitive animals. The data suggest that naturally occurring variations in the Bcl-xl/Bax ratio in the hippocampus may contribute to individual differences in vulnerability to stress-induced depression-like behaviors.

  7. Copolyimide Surface Modifying Agents for Particle Adhesion Mitigation

    NASA Technical Reports Server (NTRS)

    Wohl, Christopher J.; Connell, John W.

    2011-01-01

    Marine biofouling, insect adhesion on aircraft surfaces, microbial contamination of sterile environments, and particle contamination all present unique challenges for which researchers have adopted an array of mitigation strategies. Particulate contamination is of interest to NASA regarding exploration of the Moon, Mars, asteroids, etc.1 Lunar dust compromised seals, clogged filters, abraded visors and space suit surfaces, and was a significant health concern during the Apollo missions.2 Consequently, NASA has instituted a multi-faceted approach to address dust including use of sacrificial surfaces, active mitigation requiring the use of an external energy source, and passive mitigation utilizing materials with an intrinsic resistance to surface contamination. One passive mitigation strategy is modification of a material s surface energy either chemically or topographically. The focus of this paper is the synthesis and evaluation of novel copolyimide materials with surface modifying agents (SMA, oxetanes) enabling controlled variation of surface chemical composition.

  8. Line-edge quality optimization of electron beam resist for high-throughput character projection exposure utilizing atomic force microscope analysis

    NASA Astrophysics Data System (ADS)

    Ikeno, Rimon; Mita, Yoshio; Asada, Kunihiro

    2017-04-01

    High-throughput electron-beam lithography (EBL) by character projection (CP) and variable-shaped beam (VSB) methods is a promising technique for low-to-medium volume device fabrication with regularly arranged layouts, such as standard-cell logics and memory arrays. However, non-VLSI applications like MEMS and MOEMS may not fully utilize the benefits of CP method due to their wide variety of layout figures including curved and oblique edges. In addition, the stepwise shapes that appear on such irregular edges by VSB exposure often result in intolerable edge roughness, which may degrade performances of the fabricated devices. In our former study, we proposed a general EBL methodology for such applications utilizing a combination of CP and VSB methods, and demonstrated its capabilities in electron beam (EB) shot reduction and edge-quality improvement by using a leading-edge EB exposure tool, ADVANTEST F7000S-VD02, and high-resolution Hydrogen Silsesquioxane resist. Both scanning electron microscope and atomic force microscope observations were used to analyze quality of the resist edge profiles to determine the influence of the control parameters used in the exposure-data preparation process. In this study, we carried out detailed analysis of the captured edge profiles utilizing Fourier analysis, and successfully distinguish the systematic undulation by the exposed CP character profiles from random roughness components. Such capability of precise edge-roughness analysis is useful to our EBL methodology to maintain both the line-edge quality and the exposure throughput by optimizing the control parameters in the layout data conversion.

  9. Apparatus and Methods for Mitigating Electromagnetic Emissions

    NASA Technical Reports Server (NTRS)

    Geng, Steven M. (Inventor); Niedra, Janis M. (Inventor)

    2013-01-01

    Apparatus, methods, and other embodiments associated with mitigation of magnetic fields are described herein. In an embodiment, a method for mitigating an electromagnetic field includes positioning a mitigating coil around a linear alternator of linear motor so that the mitigating coil is coaxially located with an alternator coil; arranging the mitigating coil to generate a field to mitigate an electromagnetic field generated by the alternator coil; and passing an induced current from the alternator coil through the mitigating coil.

  10. Apparatus and Methods for Mitigating Electromagnetic Emissions

    NASA Technical Reports Server (NTRS)

    Geng, Steven M. (Inventor); Niedra, Janis M. (Inventor)

    2016-01-01

    Apparatus, methods, and other embodiments associated with mitigation of magnetic fields are described herein. In an embodiment, a method for mitigating an electromagnetic field includes positioning a mitigating coil around a linear alternator of linear motor so that the mitigating coil is coaxially located with an alternator coil; arranging the mitigating coil to generate a field to mitigate an electromagnetic field generated by the alternator coil; and passing an induced current from the alternator coil through the mitigating coil.

  11. Comparison of force exerted on the sternum during a sneeze versus during low-, moderate-, and high-intensity bench press resistance exercise with and without the valsalva maneuver in healthy volunteers.

    PubMed

    Adams, Jenny; Schmid, Jack; Parker, Robert D; Coast, J Richard; Cheng, Dunlei; Killian, Aaron D; McCray, Stephanie; Strauss, Danielle; McLeroy Dejong, Sandra; Berbarie, Rafic

    2014-03-15

    Sternal precautions are intended to prevent complications after median sternotomy, but little data exist to support the consensus recommendations. To better characterize the forces on the sternum that can occur during everyday events, we conducted a prospective nonrandomized study of 41 healthy volunteers that evaluated the force exerted during bench press resistance exercise and while sneezing. A balloon-tipped esophageal catheter, inserted through the subject's nose and advanced into the thoracic cavity, was used to measure the intrathoracic pressure differential during the study activities. After the 1 repetition maximum (1-RM) was assessed, the subject performed the bench press at the following intensities, first with controlled breathing and then with the Valsalva maneuver: 40% of 1-RM (low), 70% of 1-RM (moderate), and 1-RM (high). Next, various nasal irritants were used to induce a sneeze. The forces on the sternum were calculated according to a cylindrical model, and a 2-tailed paired t test was used to compare the mean force exerted during a sneeze with the mean force exerted during each of the 6 bench press exercises. No statistically significant difference was found between the mean force from a sneeze (41.0 kg) and the mean total force exerted during moderate-intensity bench press exercise with breathing (41.4 kg). In conclusion, current guidelines and recommendations limit patient activity after a median sternotomy. Because these patients can repeatedly withstand a sneeze, our study indicates that they can withstand the forces from more strenuous activities than are currently allowed.

  12. Toward to Disaster Mitigation Science

    NASA Astrophysics Data System (ADS)

    Kaneda, Yoshiyuki; Shiraki, Wataru; Tokozakura, Eiji

    2016-04-01

    Destructive natural disasters such as earthquakes and tsunamis have occurred frequently in the world. For the reduction and mitigation of damages by destructive natural disasters, early detection of natural disasters and speedy and proper evacuations are indispensable. And hardware and software preparations for reduction and mitigation of natural disasters are quite important and significant. Finally, methods on restorations and revivals are necessary after natural disasters. We would like to propose natural disaster mitigation science for early detections, evacuations and restorations against destructive natural disasters. In natural disaster mitigation science, there are lots of research fields such as natural science, engineering, medical treatment, social science and literature/art etc. Especially, natural science, engineering and medical treatment are fundamental research fields for natural disaster mitigation, but social sciences such as sociology, psychology etc. are very important research fields for restorations after natural disasters. We have to progress the natural disaster mitigation science against destructive natural disaster mitigation. in the near future. We will present the details of natural disaster mitigation science.

  13. Space collision threat mitigation

    NASA Astrophysics Data System (ADS)

    Zatezalo, Aleksandar; Stipanović, Dušan; Mehra, Raman K.; Pham, Khanh

    2014-06-01

    Mitigation of possible collision threats to current and future operations in space environments is an important an challenging task considering high nonlinearity of orbital dynamics and discrete measurement updates. Such discrete observations are relatively scarce with respect to space dynamics including possible unintentional or intentional rocket propulsion based maneuvers even in scenarios when measurement collections are focused to a one single target of interest. In our paper, this problem is addressed in terms of multihypothesis and multimodel estimation in conjunction with multi-agent multigoal game theoretic guaranteed evasion strategies. Collision threat estimation is formulated using conditional probabilities of time dependent hypotheses and spacecraft controls which are computed using Liapunov-like approach. Based on this formulation, time dependent functional forms of multi-objective utility functions are derived given threat collision risk levels. For demonstrating developed concepts, numerical methods are developed using nonlinear filtering methodology for updating hypothesis sets and corresponding conditional probabilities. Space platform associated sensor resources are managed using previously developed and demonstrated information-theoretic objective functions and optimization methods. Consequently, estimation and numerical methods are evaluated and demonstrated on a realistic Low Earth Orbit collision encounter.

  14. Translation Readthrough Mitigation

    PubMed Central

    Arribere, Joshua A.; Cenik, Elif S.; Jain, Nimit; Hess, Gaelen T.; Lee, Cameron H.; Bassik, Michael C.; Fire, Andrew Z.

    2016-01-01

    A fraction of ribosomes engaged in translation will fail to terminate when reaching a stop codon, yielding nascent proteins inappropriately extended on their C-termini. Although such extended proteins can interfere with normal cellular processes, known mechanisms of translational surveillance are insufficient to protect cells from potential dominant consequences. Through a combination of transgenics and CRISPR/Cas9 gene editing in C. elegans, we demonstrate a consistent ability of cells to block accumulation of C-terminal extended proteins that result from failure to terminate at stop codons. 3’UTR-encoded sequences were sufficient to lower protein levels. Measurements of mRNA levels and translation suggested a co- or post-translational mechanism of action for these sequences in C. elegans. Similar mechanisms evidently operate in human cells, where we observed a comparable tendency for translated human 3’UTR sequences to reduce mature protein expression in tissue culture assays, including 3' sequences from the hypomorphic “Constant Spring” hemoglobin stop codon variant. We suggest 3’UTRs may encode peptide sequences that destabilize the attached protein, providing mitigation of unwelcome and varied translation errors. PMID:27281202

  15. Translation readthrough mitigation.

    PubMed

    Arribere, Joshua A; Cenik, Elif S; Jain, Nimit; Hess, Gaelen T; Lee, Cameron H; Bassik, Michael C; Fire, Andrew Z

    2016-06-30

    A fraction of ribosomes engaged in translation will fail to terminate when reaching a stop codon, yielding nascent proteins inappropriately extended on their C termini. Although such extended proteins can interfere with normal cellular processes, known mechanisms of translational surveillance are insufficient to protect cells from potential dominant consequences. Here, through a combination of transgenics and CRISPR–Cas9 gene editing in Caenorhabditis elegans, we demonstrate a consistent ability of cells to block accumulation of C-terminal-extended proteins that result from failure to terminate at stop codons. Sequences encoded by the 3′ untranslated region (UTR) were sufficient to lower protein levels. Measurements of mRNA levels and translation suggested a co- or post-translational mechanism of action for these sequences in C. elegans. Similar mechanisms evidently operate in human cells, in which we observed a comparable tendency for translated human 3′ UTR sequences to reduce mature protein expression in tissue culture assays, including 3′ UTR sequences from the hypomorphic ‘Constant Spring’ haemoglobin stop codon variant. We suggest that 3′ UTRs may encode peptide sequences that destabilize the attached protein, providing mitigation of unwelcome and varied translation errors.

  16. Mitigation analysis for Estonia

    SciTech Connect

    Martins, A.; Roos, J.; Pesur, A.

    1996-09-01

    The present report provides data on the mitigation analysis of Estonia. The results for energy, forest and agricultural sectors and macro-economic analysis are given. The Government of Estonia has identified the development of energy production as the main strategical means in the movement towards market economy. Now 99% of electricity generation and about 25% of heat production in Estonia is based on oil shale combustion. To increase the efficiency of oil shale-fired power plants and decrease CO{sub 2} emissions, the State Enterprise (SE) Eesti Energia (Estonian Energy) is planning to reconstruct these power plants and introduce the Circulating Fluidized Bed (CFB) combustion technology for oil shale burning to replace the Pulverized Combustion (PC). According to the Estonian Forest Policy, two general objectives are of importance: sustainability in forestry and efficiency in forest management. For the reduction of greenhouse gases (GHG) emissions from agriculture, it is necessary to increase the efficiency of production resource usage. The growth of the GDP in 1995 was 2.9% as a result of large-scale privatization activities in Estonia and re-introduction of the available, but unused production capacities with the help of foreign and domestic investments. It is assumed that the medium growth rate of GDP reaches 6% in 1998.

  17. Protect Thy Neighbor: Investigating the Spatial Externalities of Community Wildfire Hazard Mitigation

    Treesearch

    David Butry; Geoffrey Donovan

    2008-01-01

    Climate change, increased wildland fuels, and residential development patterns in fire-prone areas all combine to make wildfire risk mitigation an important public policy issue. One approach to wildfire risk mitigation is to encourage homeowners to use fire-resistant building materials and to create defensible spaces around their homes. We develop a theoretical model...

  18. Albeni Falls Wildlife Mitigation Project : Annual Report of Mitigation Activities.

    SciTech Connect

    Entz, Ray D.

    2001-04-01

    The Albeni Falls Interagency Work Group was actively involved in implementing wildlife mitigation activities in 2000. The Work Group met each quarter to discuss management and budget issues affecting Albeni Falls wildlife mitigation. Members of the Work Group protected a total of 1,242 acres of wetland habitat in 2000. The total amount of wildlife habitat protected for Albeni Falls mitigation is approximately 4,190 acres (4,630 Habitat Units). Approximately 16% of the total wildlife habitat lost has been mitigated. Land management activities were limited in 2000 as protection opportunities took up most staff time. Administrative activities increased in 2000 as funding was more evenly distributed among Work Group members. As a result, implementation is expected to continue to increase in the coming year. Land management and monitoring and evaluation activities will increase in 2001 as site-specific management plans are completed and implemented.

  19. Comparison of Combined Aerobic and High-Force Eccentric Resistance Exercise With Aerobic Exercise Only for People With Type 2 Diabetes Mellitus

    PubMed Central

    Marcus, Robin L; Smith, Sheldon; Morrell, Glen; Addison, Odessa; Dibble, Leland E; Wahoff-Stice, Donna; LaStayo, Paul C

    2008-01-01

    Background and Purpose: The purpose of this study was to compare the outcomes between a diabetes exercise training program using combined aerobic and high-force eccentric resistance exercise and a program of aerobic exercise only. Subjects and Methods: Fifteen participants with type 2 diabetes mellitus (T2DM) participated in a 16-week supervised exercise training program: 7 (mean age=50.7 years, SD=6.9) in a combined aerobic and eccentric resistance exercise program (AE/RE group) and 8 (mean age=58.5 years, SD=6.2) in a program of aerobic exercise only (AE group). Outcome measures included thigh lean tissue and intramuscular fat (IMF), glycosylated hemoglobin, body mass index (BMI), and 6-minute walk distance. Results: Both groups experienced decreases in mean glycosylated hemoglobin after training (AE/RE group: −0.59% [95% confidence interval (CI)=−1.5 to 0.28]; AE group: −0.31% [95% CI=−0.60 to −0.03]), with no significant between-group differences. There was an interaction between group and time with respect to change in thigh lean tissue cross-sectional area, with the AE/RE group gaining more lean tissue (AE/RE group: 15.1 cm2 [95% CI=7.6 to 22.5]; AE group: −5.6 cm2 [95% CI=−10.4 to 0.76]). Both groups experienced decreases in mean thigh IMF cross-sectional area (AE/RE group: −1.2 cm2 [95% CI=−2.6 to 0.26]; AE group: −2.2 cm2 [95% CI=−3.5 to −0.84]) and increases in 6-minute walk distance (AE/RE group: 45.5 m [95% CI=7.5 to 83.6]; AE group: 29.9 m [95% CI=−7.7 to 67.5]) after training, with no between-group differences. There was an interaction between group and time with respect to change in BMI, with the AE/RE group experiencing a greater decrease in BMI. Discussion and Conclusion: Significant improvements in long-term glycemic control, thigh composition, and physical performance were demonstrated in both groups after participating in a 16-week exercise program. Subjects in the AE/RE group demonstrated additional improvements in

  20. Forced marriage, forced sex: the perils of childhood for girls.

    PubMed

    Ouattara, M; Sen, P; Thomson, M

    1998-11-01

    A recently formed interagency Forum on the Rights of Girls and Women in Marriage is investigating the widespread problem of nonconsensual marriage and forced sex and advocating for legislative and policy initiatives. This article reviews three research projects in this area: research by Anti-Slavery International on child marriage in parts of West Africa, an investigation by Save the Children of children's views of early marriage, and research conducted by CHANGE on women's resistance to domestic violence in Calcutta, India. Girls who marry before 15 years of age are more likely to be illiterate than their older counterparts, more likely to be dowry payment brides, less likely to come into contact with development projects, have higher rates of infant mortality, and are most vulnerable to sexual violence. In many cases, intercourse is initiated before the girl begins to menstruate. Although adult women also face sexual violence within marriage, this problem is all the more traumatic for girls who lack any information about sexuality. Sex with girls below a certain age is usually covered by rape legislation, but, in countries such as India, this is mitigated by the religiously defined personal laws. The absence of adequate legal and policy action frameworks to deal with the rights of girls, coupled with the lack of sanctions against these abuses, comprise state complicity and neglect of duty under international law to this vulnerable group.

  1. Stream Mitigation Protocol Compendium - 2004

    EPA Pesticide Factsheets

    This document is intended as a reference in order to select, adapt, or devise stream assessment methods appropriate for impact assessment and mitigation of fluvial resources in the CWA Section 404 Program.

  2. National Wetlands Mitigation Action Plan

    EPA Pesticide Factsheets

    On December 26, 2002, EPA and the Corps of Engineers announced the release of a comprehensive, interagency National Wetlands Mitigation Action Plan to further achievement of the goal of no net loss of wetlands.

  3. Robust dynamic mitigation of instabilities

    SciTech Connect

    Kawata, S.; Karino, T.

    2015-04-15

    A dynamic mitigation mechanism for instability growth was proposed and discussed in the paper [S. Kawata, Phys. Plasmas 19, 024503 (2012)]. In the present paper, the robustness of the dynamic instability mitigation mechanism is discussed further. The results presented here show that the mechanism of the dynamic instability mitigation is rather robust against changes in the phase, the amplitude, and the wavelength of the wobbling perturbation applied. Generally, instability would emerge from the perturbation of the physical quantity. Normally, the perturbation phase is unknown so that the instability growth rate is discussed. However, if the perturbation phase is known, the instability growth can be controlled by a superposition of perturbations imposed actively: If the perturbation is induced by, for example, a driving beam axis oscillation or wobbling, the perturbation phase could be controlled, and the instability growth is mitigated by the superposition of the growing perturbations.

  4. Fiscally Informed Total Force Manpower

    DTIC Science & Technology

    2008-01-01

    manpower requirements and within fiscal limits and acceptable levels of risk identified in DoD planning and programming guidance. In 2006, DoD issued...operating at a time when it must carefully balance resources to recapitalize major equipment—all while mitigating operational risk . DoD is carefully...Total Force4 work- forces that enable key capabilities, deliver readiness, are cost-effective, and balance risk . Demand exists both in the military and

  5. Extended MHD simulations for application to ITER disruption mitigation techniques

    NASA Astrophysics Data System (ADS)

    Woodruff, Simon; Stuber, James; Schetterer, Sam; ITER Disruption Mitigation Collaboration

    2013-10-01

    Various disruption scenarios are modeled computationally by use of the CORSICA and NIMROD codes, following the work of Kruger and Strauss with the aim of providing starting-points for investigation of tokamak disruption mitigation techniques. It is found that pressure-driven instabilities previously observed in simulations of DIII-D are verified, and that halo currents from vertical displacements are observed in simulations with implementation of resistive walls for ITER. We discuss implications and plans for simulations of disruption mitigation techniques. We outline validation activities for existing facilities. Work performed for USITER under DE-AC05-00OR22725 subcontract # 4000118643.

  6. Mitigating amphibian chytridiomycosis in nature

    USGS Publications Warehouse

    Garner, Trenton W. J.; Schmidt, Benedikt R.; Martel, An; Pasmans, Frank; Muths, Erin L.; Cunningham, Andrew A.; Weldon, Che; Fisher, Matthew C.; Bosch, Jaime

    2016-01-01

    Amphibians across the planet face the threat of population decline and extirpation caused by the disease chytridiomycosis. Despite consensus that the fungal pathogens responsible for the disease are conservation issues, strategies to mitigate their impacts in the natural world are, at best, nascent. Reducing risk associated with the movement of amphibians, non-amphibian vectors and other sources of infection remains the first line of defence and a primary objective when mitigating the threat of disease in wildlife. Amphibian-associated chytridiomycete fungi and chytridiomycosis are already widespread, though, and we therefore focus on discussing options for mitigating the threats once disease emergence has occurred in wild amphibian populations. All strategies have shortcomings that need to be overcome before implementation, including stronger efforts towards understanding and addressing ethical and legal considerations. Even if these issues can be dealt with, all currently available approaches, or those under discussion, are unlikely to yield the desired conservation outcome of disease mitigation. The decision process for establishing mitigation strategies requires integrated thinking that assesses disease mitigation options critically and embeds them within more comprehensive strategies for the conservation of amphibian populations, communities and ecosystems.

  7. Mitigating amphibian chytridiomycoses in nature.

    PubMed

    Garner, Trenton W J; Schmidt, Benedikt R; Martel, An; Pasmans, Frank; Muths, Erin; Cunningham, Andrew A; Weldon, Che; Fisher, Matthew C; Bosch, Jaime

    2016-12-05

    Amphibians across the planet face the threat of population decline and extirpation caused by the disease chytridiomycosis. Despite consensus that the fungal pathogens responsible for the disease are conservation issues, strategies to mitigate their impacts in the natural world are, at best, nascent. Reducing risk associated with the movement of amphibians, non-amphibian vectors and other sources of infection remains the first line of defence and a primary objective when mitigating the threat of disease in wildlife. Amphibian-associated chytridiomycete fungi and chytridiomycosis are already widespread, though, and we therefore focus on discussing options for mitigating the threats once disease emergence has occurred in wild amphibian populations. All strategies have shortcomings that need to be overcome before implementation, including stronger efforts towards understanding and addressing ethical and legal considerations. Even if these issues can be dealt with, all currently available approaches, or those under discussion, are unlikely to yield the desired conservation outcome of disease mitigation. The decision process for establishing mitigation strategies requires integrated thinking that assesses disease mitigation options critically and embeds them within more comprehensive strategies for the conservation of amphibian populations, communities and ecosystems.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'. © 2016 The Author(s).

  8. Discrete fiber-reinforced polyurea systems for infrastructure strengthening and blast mitigation

    NASA Astrophysics Data System (ADS)

    Carey, Natalia L.

    The research presented in this dissertation focused on evaluating the effectiveness of various blast mitigation materials and coating technologies to be used for enhancing blast resistance of structural members. Mechanical properties and blast mitigation performance of different discrete fiber-reinforced polyurea (DFRP) systems were investigated through experimental and analytical work. Four technical papers discuss the research efforts conducted within this dissertation. The first paper examined the development and characterization of different DFRP systems for infrastructure strengthening and blast retrofit. The behavior of various systems which consisted of chopped E-glass fibers discretely integrated in with the polyurea matrix was evaluated through coupon tensile testing. The addition of glass fiber to a polymer coating provided improved stiffness and strength to the composite system while the polyurea base material provided ductility. The second paper evaluated the behavior of hybrid, plain, and steel fiber-reinforced concrete panels coated with various polyurea and DFRP systems under blast loading. Hybrid panels demonstrated higher blast mitigation performance compared to plain and steel fiber-reinforced concrete panels due to sacrificial hybrid layer. The addition of plain polyurea or DFRP systems on the tension side improved panel performance by containing fragmentation during a blast event. The third paper presents an analytical investigation conducted using the explicit finite element program LS-DYNA to model panel and coating response under blast loading. Several modeling solutions were undertaken and compared for concrete formulation. Modeling results were analyzed and compared to the experimental work to validate the conclusions. The final paper describes an internal equilibrium mechanics based model developed to predict the flexural capacity of reinforced concrete beams strengthened with various DFRP systems. The developed model was validated using

  9. Mitigating the Cultural Challenges of SOF/Conventional Force Interdependence

    DTIC Science & Technology

    2013-03-01

    cultures may be their strengths.” 53 ADML James G. Stravidis, USN, “Strengthening the Bridge: Building Partner Capacity”, Military Review (Jan-Feb 2010...http://www.army.mil/article/35028/Strengthening_the_Bridge__ Building_Partnership_Capacity/ (accessed January 16, 2013). ADML Stravidis quotes Mike...Mullen, ADML , USN, as saying "Developing a relationship on the battlefield in the midst of a crisis with someone I’ve never met before can be very

  10. Computational Models of Exercise on the Advanced Resistance Exercise Device (ARED)

    NASA Technical Reports Server (NTRS)

    Newby, Nate; Caldwell, Erin; Scott-Pandorf, Melissa; Peters,Brian; Fincke, Renita; DeWitt, John; Poutz-Snyder, Lori

    2011-01-01

    Muscle and bone loss remain a concern for crew returning from space flight. The advanced resistance exercise device (ARED) is used for on-orbit resistance exercise to help mitigate these losses. However, characterization of how the ARED loads the body in microgravity has yet to be determined. Computational models allow us to analyze ARED exercise in both 1G and 0G environments. To this end, biomechanical models of the squat, single-leg squat, and deadlift exercise on the ARED have been developed to further investigate bone and muscle forces resulting from the exercises.

  11. Global climate change and the mitigation challenge.

    PubMed

    Princiotta, Frank

    2009-10-01

    Anthropogenic emissions of greenhouse gases, especially carbon dioxide (CO2), have led to increasing atmospheric concentrations, very likely the primary cause of the 0.8 degrees C warming the Earth has experienced since the Industrial Revolution. With industrial activity and population expected to increase for the rest of the century, large increases in greenhouse gas emissions are projected, with substantial global additional warming predicted. This paper examines forces driving CO2 emissions, a concise sector-by-sector summary of mitigation options, and research and development (R&D) priorities. To constrain warming to below approximately 2.5 degrees C in 2100, the recent annual 3% CO2 emission growth rate needs to transform rapidly to an annual decrease rate of from 1 to 3% for decades. Furthermore, the current generation of energy generation and end-use technologies are capable of achieving less than half of the emission reduction needed for such a major mitigation program. New technologies will have to be developed and deployed at a rapid rate, especially for the key power generation and transportation sectors. Current energy technology research, development, demonstration, and deployment (RDD&D) programs fall far short of what is required.

  12. Global climate change and the mitigation challenge

    SciTech Connect

    Frank Princiotta

    2009-10-15

    Anthropogenic emissions of greenhouse gases, especially carbon dioxide (CO{sub 2}), have led to increasing atmospheric concentrations, very likely the primary cause of the 0.8{sup o}C warming the Earth has experienced since the Industrial Revolution. With industrial activity and population expected to increase for the rest of the century, large increases in greenhouse gas emissions are projected, with substantial global additional warming predicted. This paper examines forces driving CO{sub 2} emissions, a concise sector-by-sector summary of mitigation options, and research and development (R&D) priorities. To constrain warming to below approximately 2.5{sup o}C in 2100, the recent annual 3% CO{sub 2} emission growth rate needs to transform rapidly to an annual decrease rate of from 1 to 3% for decades. Furthermore, the current generation of energy generation and end-use technologies are capable of achieving less than half of the emission reduction needed for such a major mitigation program. New technologies will have to be developed and deployed at a rapid rate, especially for the key power generation and transportation sectors. Current energy technology research, development, demonstration, and deployment (RDD&D) programs fall far short of what is required. 20 refs., 18 figs., 4 tabs.

  13. Epidemiology today: Mitigating threats to an ecosystem.

    PubMed

    Kreiger, Nancy

    2016-06-27

    Ecosystems comprise all the living and non-living things in a particular area (e.g., rain forest, desert), which interact and maintain equilibrium. Loss of equilibrium (e.g., clear-cutting trees in a rain forest) can mean the decline of the ecosystem, unless it is able to adapt to the new circumstances. The term "knowledge ecosystem" describes an approach to managing knowledge in a particular field; the components of this system include the people, the technological skills and resources, and information or data. Epidemiology can be thought of as a knowledge ecosystem and, like ecological systems, its existence can be threatened, from both internal and external forces that may alter its equilibrium. This paper describes some threats to the epidemiology knowledge ecosystem, how these threats came about, and what responses we can make that may serve to mitigate those threats.

  14. Task Force IV: Environment and Natural Resources

    ERIC Educational Resources Information Center

    Appalachia, 1977

    1977-01-01

    Summarizing the Task Force Issues Paper presented at the Appalachian Conference on Balanced Growth and Economic Development (1977), this article presents Task Force recommendations on: the price of growth; relaxation of environmental regulations; mitigation of regional impact costs; policy regarding the use of public lands; growth management…

  15. NASA's Research in Aircraft Vulnerability Mitigation

    NASA Technical Reports Server (NTRS)

    Allen, Cheryl L.

    2005-01-01

    Since its inception in 1958, the National Aeronautics and Space Administration s (NASA) role in civil aeronautics has been to develop high-risk, high-payoff technologies to meet critical national aviation challenges. Following the events of Sept. 11, 2001, NASA recognized that it now shared the responsibility for improving homeland security. The NASA Strategic Plan was modified to include requirements to enable a more secure air transportation system by investing in technologies and collaborating with other agencies, industry, and academia. NASA is conducting research to develop and advance innovative and commercially viable technologies that will reduce the vulnerability of aircraft to threats or hostile actions, and identify and inform users of potential vulnerabilities in a timely manner. Presented in this paper are research plans and preliminary status for mitigating the effects of damage due to direct attacks on civil transport aircraft. The NASA approach to mitigation includes: preventing loss of an aircraft due to a hit from man-portable air defense systems; developing fuel system technologies that prevent or minimize in-flight vulnerability to small arms or other projectiles; providing protection from electromagnetic energy attacks by detecting directed energy threats to aircraft and on/off-board systems; and minimizing the damage due to high-energy attacks (explosions and fire) by developing advanced lightweight, damage-resistant composites and structural concepts. An approach to preventing aircraft from being used as weapons of mass destruction will also be discussed.

  16. The Cytoskeleton and Force Response Mechanisms

    NASA Technical Reports Server (NTRS)

    Allen, Philip Goodwin

    2003-01-01

    The long term aim of this project was to define the mechanisms by which cells sense and respond to the physical forces experienced at 1g and missing in microgravity. Identification and characterization of the elements of the cells force response mechanism could provide pathways and molecules to serve as targets for pharmacological intervention to mitigate the pathologic effects of microgravity. Mechanical forces experienced by the organism can be transmitted to cells through molecules that allow cells to bind to the extracellular matrix and through other types of molecules which bind cells to each other. These molecules are coupled in large complexes of proteins to structural elements such as the actin cytoskeleton that give the cell the ability to sense, resist and respond to force. Application of small forces to tissue culture cells causes local elevation of intracellular calcium through stretch activated ion channels, increased tyrosine phosphorylation and a restructuring of the actin cytoskeleton. Using collagen coated iron oxide beads and strong magnets, we can apply different levels of force to cells in culture. We have found that force application causes the cells to polymerize actin at the site of mechanical deformation and unexpectedly, to depolymerize actin across the rest of the cell. Observations of GFP- actin expressing cells demonstrate that actin accumulates at the site of deformation within the first five minutes of force application and is maintained for many tens of minutes after force is removed. Consistent with the reinforcement of the cytoskeletal structures underlying the integrin-bead interaction, force also alters the motion of bound magnetic beads. This effect is seen following the removal of the magnetic field, and is only partially ablated by actin disruption with cytochalsin B. While actin is polymerizing locally at the site of force application, force also stimulates a global reduction in actin filament content within the cells. We have

  17. The Cytoskeleton and Force Response Mechanisms

    NASA Technical Reports Server (NTRS)

    Allen, Philip Goodwin

    2003-01-01

    The long term aim of this project was to define the mechanisms by which cells sense and respond to the physical forces experienced at 1g and missing in microgravity. Identification and characterization of the elements of the cells force response mechanism could provide pathways and molecules to serve as targets for pharmacological intervention to mitigate the pathologic effects of microgravity. Mechanical forces experienced by the organism can be transmitted to cells through molecules that allow cells to bind to the extracellular matrix and through other types of molecules which bind cells to each other. These molecules are coupled in large complexes of proteins to structural elements such as the actin cytoskeleton that give the cell the ability to sense, resist and respond to force. Application of small forces to tissue culture cells causes local elevation of intracellular calcium through stretch activated ion channels, increased tyrosine phosphorylation and a restructuring of the actin cytoskeleton. Using collagen coated iron oxide beads and strong magnets, we can apply different levels of force to cells in culture. We have found that force application causes the cells to polymerize actin at the site of mechanical deformation and unexpectedly, to depolymerize actin across the rest of the cell. Observations of GFP- actin expressing cells demonstrate that actin accumulates at the site of deformation within the first five minutes of force application and is maintained for many tens of minutes after force is removed. Consistent with the reinforcement of the cytoskeletal structures underlying the integrin-bead interaction, force also alters the motion of bound magnetic beads. This effect is seen following the removal of the magnetic field, and is only partially ablated by actin disruption with cytochalsin B. While actin is polymerizing locally at the site of force application, force also stimulates a global reduction in actin filament content within the cells. We have

  18. Mechanism of Edge Localized Mode Mitigation by Resonant Magnetic Perturbations

    NASA Astrophysics Data System (ADS)

    Bécoulet, M.; Orain, F.; Huijsmans, G. T. A.; Pamela, S.; Cahyna, P.; Hoelzl, M.; Garbet, X.; Franck, E.; Sonnendrücker, E.; Dif-Pradalier, G.; Passeron, C.; Latu, G.; Morales, J.; Nardon, E.; Fil, A.; Nkonga, B.; Ratnani, A.; Grandgirard, V.

    2014-09-01

    A possible mechanism of edge localized modes (ELMs) mitigation by resonant magnetic perturbations (RMPs) is proposed based on the results of nonlinear resistive magnetohydrodynamic modeling using the jorek code, realistic JET-like plasma parameters and an RMP spectrum of JET error-field correction coils (EFCC) with a main toroidal number n =2 were used in the simulations. Without RMPs, a large ELM relaxation is obtained mainly due to the most unstable medium-n ballooning mode. The externally imposed RMP drives nonlinearly the modes coupled to n =2 RMP which produce small multimode relaxations, mitigated ELMs. The modes driven by RMPs exhibit a tearinglike structure and produce additional islands. Mitigated ELMs deposit energy into the divertor mainly in the structures ("footprints") created by n =2 RMPs, however, slightly modulated by other nonlinearly driven even harmonics. The divertor power flux during a ELM phase mitigated by RMPs is reduced almost by a factor of 10. The mechanism of ELM mitigation by RMPs proposed here reproduces generic features of high collisionality RMP experiments, where large ELMs are replaced by small, much more frequent ELMs or magnetic turbulence. Total ELM suppression was also demonstrated in modeling at higher RMP amplitude.

  19. Mechanism of edge localized mode mitigation by resonant magnetic perturbations.

    PubMed

    Bécoulet, M; Orain, F; Huijsmans, G T A; Pamela, S; Cahyna, P; Hoelzl, M; Garbet, X; Franck, E; Sonnendrücker, E; Dif-Pradalier, G; Passeron, C; Latu, G; Morales, J; Nardon, E; Fil, A; Nkonga, B; Ratnani, A; Grandgirard, V

    2014-09-12

    A possible mechanism of edge localized modes (ELMs) mitigation by resonant magnetic perturbations (RMPs) is proposed based on the results of nonlinear resistive magnetohydrodynamic modeling using the jorek code, realistic JET-like plasma parameters and an RMP spectrum of JET error-field correction coils (EFCC) with a main toroidal number n=2 were used in the simulations. Without RMPs, a large ELM relaxation is obtained mainly due to the most unstable medium-n ballooning mode. The externally imposed RMP drives nonlinearly the modes coupled to n=2 RMP which produce small multimode relaxations, mitigated ELMs. The modes driven by RMPs exhibit a tearinglike structure and produce additional islands. Mitigated ELMs deposit energy into the divertor mainly in the structures ("footprints") created by n=2 RMPs, however, slightly modulated by other nonlinearly driven even harmonics. The divertor power flux during a ELM phase mitigated by RMPs is reduced almost by a factor of 10. The mechanism of ELM mitigation by RMPs proposed here reproduces generic features of high collisionality RMP experiments, where large ELMs are replaced by small, much more frequent ELMs or magnetic turbulence. Total ELM suppression was also demonstrated in modeling at higher RMP amplitude.

  20. An investigation on the mitigation of end-stop impacts in a magnetorheological damper operated by the mixed mode

    NASA Astrophysics Data System (ADS)

    Yazid, I. I. M.; Mazlan, S. A.; Imaduddin, F.; Zamzuri, H.; Choi, S. B.; Kikuchi, T.

    2016-12-01

    This paper presents mitigation behaviour of magnetorheological (MR) damper operated with a mixed working modes. A combination of the shear and squeeze modes is employed in the structure of MR damper to obtain the field-dependent normal yield stress as well as strengthen the squeeze effect. The experimental evaluation shows that when the piston is squeezing the bottom gap from the stroke of 25 to 26 mm, the sudden increase of squeeze force is observed confirming the existence of the mitigation effect. It is also observed that the magnitude of mitigation force is positively correlated with the magnitude of current given to the electromagnet. The measured peak mitigation forces are ranged from 722 N to 1032 N when the electromagnet currents are varied from 0.2 A to 0.8 A, respectively. The variable mitigation effect indicates that the concept can be further discussed as a potential impact protection feature in an MR damper.

  1. Greenhouse gas mitigation in agriculture.

    PubMed

    Smith, Pete; Martino, Daniel; Cai, Zucong; Gwary, Daniel; Janzen, Henry; Kumar, Pushpam; McCarl, Bruce; Ogle, Stephen; O'Mara, Frank; Rice, Charles; Scholes, Bob; Sirotenko, Oleg; Howden, Mark; McAllister, Tim; Pan, Genxing; Romanenkov, Vladimir; Schneider, Uwe; Towprayoon, Sirintornthep; Wattenbach, Martin; Smith, Jo

    2008-02-27

    Agricultural lands occupy 37% of the earth's land surface. Agriculture accounts for 52 and 84% of global anthropogenic methane and nitrous oxide emissions. Agricultural soils may also act as a sink or source for CO2, but the net flux is small. Many agricultural practices can potentially mitigate greenhouse gas (GHG) emissions, the most prominent of which are improved cropland and grazing land management and restoration of degraded lands and cultivated organic soils. Lower, but still significant mitigation potential is provided by water and rice management, set-aside, land use change and agroforestry, livestock management and manure management. The global technical mitigation potential from agriculture (excluding fossil fuel offsets from biomass) by 2030, considering all gases, is estimated to be approximately 5500-6000Mt CO2-eq.yr-1, with economic potentials of approximately 1500-1600, 2500-2700 and 4000-4300Mt CO2-eq.yr-1 at carbon prices of up to 20, up to 50 and up to 100 US$ t CO2-eq.-1, respectively. In addition, GHG emissions could be reduced by substitution of fossil fuels for energy production by agricultural feedstocks (e.g. crop residues, dung and dedicated energy crops). The economic mitigation potential of biomass energy from agriculture is estimated to be 640, 2240 and 16 000Mt CO2-eq.yr-1 at 0-20, 0-50 and 0-100 US$ t CO2-eq.-1, respectively.

  2. Comparison of turbulence mitigation algorithms

    NASA Astrophysics Data System (ADS)

    Kozacik, Stephen T.; Paolini, Aaron; Sherman, Ariel; Bonnett, James; Kelmelis, Eric

    2017-07-01

    When capturing imagery over long distances, atmospheric turbulence often degrades the data, especially when observation paths are close to the ground or in hot environments. These issues manifest as time-varying scintillation and warping effects that decrease the effective resolution of the sensor and reduce actionable intelligence. In recent years, several image processing approaches to turbulence mitigation have shown promise. Each of these algorithms has different computational requirements, usability demands, and degrees of independence from camera sensors. They also produce different degrees of enhancement when applied to turbulent imagery. Additionally, some of these algorithms are applicable to real-time operational scenarios while others may only be suitable for postprocessing workflows. EM Photonics has been developing image-processing-based turbulence mitigation technology since 2005. We will compare techniques from the literature with our commercially available, real-time, GPU-accelerated turbulence mitigation software. These comparisons will be made using real (not synthetic), experimentally obtained data for a variety of conditions, including varying optical hardware, imaging range, subjects, and turbulence conditions. Comparison metrics will include image quality, video latency, computational complexity, and potential for real-time operation. Additionally, we will present a technique for quantitatively comparing turbulence mitigation algorithms using real images of radial resolution targets.

  3. Remote Sensing Technologies Mitigate Drought

    NASA Technical Reports Server (NTRS)

    2015-01-01

    Ames Research Center has partnered with the California Department of Water Resources to develop satellite-based technologies to mitigate drought conditions. One project aims to help water managers adjust their irrigation to match the biological needs of each crop, and another involves monitoring areas where land is fallow so emergency relief can more quickly aid affected communities.

  4. The Vulnerability Assessment & Mitigation Methodology

    DTIC Science & Technology

    2003-01-01

    Defense Systems........................................ 111 A.37. Vulnerabilities That Can Be Incurred from Vaccination ........... 112 A.38...protect against future threats or system failures while mitigating current and past threats and weaknesses. Also, sophisticated adver - saries are...and recovery • Adaptability and learning • Immunological defense systems • Vaccination ISR and Self-Awareness • Intelligence operations • Self

  5. Space debris detection and mitigation

    SciTech Connect

    Allahdadi, F.

    1993-01-01

    Space debris is defined as all useless man-made objects in space. This conference covers the following areas: debris detection, tracking, and surveillance; orbital debris analytical modeling; debris environment and safety issues; and orbital debris mitigation. Separate abstracts were prepared for 26 papers in this conference.

  6. Lunar Dust: Characterization and Mitigation

    NASA Technical Reports Server (NTRS)

    Hyatt. Mark J.; Feighery, John

    2007-01-01

    Lunar dust is a ubiquitous phenomenon which must be explicitly addressed during upcoming human lunar exploration missions. Near term plans to revisit the moon as a stepping stone for further exploration of Mars, and beyond, places a primary emphasis on characterization and mitigation of lunar dust. Comprised of regolith particles ranging in size from tens of nanometers to microns, lunar dust is a manifestation of the complex interaction of the lunar soil with multiple mechanical, electrical, and gravitational effects. The environmental and anthropogenic factors effecting the perturbation, transport, and deposition of lunar dust must be studied in order to mitigate it's potentially harmful effects on exploration systems. The same hold true for assessing the risk it may pose for toxicological health problems if inhaled. This paper presents the current perspective and implementation of dust knowledge management and integration, and mitigation technology development activities within NASA's Exploration Technology Development Program. This work is presented within the context of the Constellation Program's Integrated Lunar Dust Management Strategy. This work further outlines the scientific basis for lunar dust behavior, it's characteristics and potential effects, and surveys several potential strategies for its control and mitigation both for lunar surface operations and within the working volumes of a lunar outpost. The paper also presents a perspective on lessons learned from Apollo and forensics engineering studies of Apollo hardware.

  7. Radiosensitizers, radioprotectors, and radiation mitigators.

    PubMed

    Raviraj, Jayam; Bokkasam, Vijay Kumar; Kumar, Venkata Suneel; Reddy, Uday Shankar; Suman, Venkata

    2014-01-01

    Radiotherapy is regarded as one of the most important therapeutic modality for the treatment of malignant lesions. This field is undergoing rapid advancements in the recent times. With the use of radiosensitizers and radioprotective agents, the course of radiotherapy has improved the sensitization of tumor cells and protection of normal cells, respectively. The aim of this paper was to critically review and analyze the available compounds used as radiosensitizers, radioprotectors, and radiation mitigators. For reviewing, the author used the electronic search for the keywords 'Radiosensitizers', 'Radioprotectors', 'Radiation mitigators' on PubMed for inclusion of previously published articles and further search of reference papers on individual radiosensitizing and radioprotecting agents was done. Radiosensitizers are agents that sensitize the tumor cells to radiation. These compounds apparently promote fixation of the free radicals produced by radiation damage at the molecular level. The mechanism of action is similar to the oxygen effect, in which biochemical reactions in the damaged molecules prevent repair of the cellular radiation damage. Free radicals such as OH + are captured by the electron affinity of the radiosensitizers, rendering the molecules incapable of repair. Radioprotectors are compounds that are designed to reduce the damage in normal tissues caused by radiation. These compounds are often antioxidants and must be present before or at the time of radiation for effectiveness. Other agents, termed mitigators, may be used to minimize toxicity even after radiation has been delivered. This article tries to discuss the various aspects of radiosensitizers, radioprotectors, and radiation mitigators including the newer agents.

  8. RADON MITIGATION STUDIES: NASHVILLE DEMONSTRATION

    EPA Science Inventory

    The report gives results of an EPA radon mitigation demonstration project involving 14 houses in the Nashville, TN, area with indoor radon levels of 5.6-47.6 pCi/L, using a variety of techniques, designed to be the most cost effective methods possible to implement, and yet adequa...

  9. Mitigating Radicalism in Northern Nigeria

    DTIC Science & Technology

    2013-08-01

    radicalization in northern Nigeria. u Active engagement of youth and communities in peacebuilding programs that facilitate interactions among individuals...leaders, sustained development investments in marginalized communities , promotion of values of inclusivity to mitigate the spread of extremist ideology...claiming to have repelled Boko Haram, the militants return, regroup, and seek revenge. As a result, social and economic activities in the northern

  10. Mitigating Higher Ed Cyber Attacks

    ERIC Educational Resources Information Center

    Rogers, Gary; Ashford, Tina

    2015-01-01

    In this presentation we will discuss the many and varied cyber attacks that have recently occurred in the higher ed community. We will discuss the perpetrators, the victims, the impact and how these institutions have evolved to meet this threat. Mitigation techniques and defense strategies will be covered as will a discussion of effective security…

  11. CMAS Degradation of Environmental Barrier Coatings: Mechanisms and Mitigation

    DTIC Science & Technology

    2013-09-30

    design may require three environmental barriers, one for oxidation (Si02 TGO), one for volatilization (YDS/YMS) and one for CMAS (RE zirconate or hafnate...the rare earth zirconates (REZOa) that show prom- ise for CMAS resistance must be applied with a segment- ed or porous structure to minimize the...serving as a water vapor barrier is referred to as the ’EBC while TBC is used to describe the segmented zirconate /hafnate layer intended to mitigate

  12. Lunar Dust Mitigation Technology Development

    NASA Technical Reports Server (NTRS)

    Hyatt, Mark J.; Deluane, Paul B.

    2008-01-01

    NASA s plans for implementing the Vision for Space Exploration include returning to the moon as a stepping stone for further exploration of Mars, and beyond. Dust on the lunar surface has a ubiquitous presence which must be explicitly addressed during upcoming human lunar exploration missions. While the operational challenges attributable to dust during the Apollo missions did not prove critical, the comparatively long duration of impending missions presents a different challenge. Near term plans to revisit the moon places a primary emphasis on characterization and mitigation of lunar dust. Comprised of regolith particles ranging in size from tens of nanometers to microns, lunar dust is a manifestation of the complex interaction of the lunar soil with multiple mechanical, electrical, and gravitational effects. The environmental and anthropogenic factors effecting the perturbation, transport, and deposition of lunar dust must be studied in order to mitigate it s potentially harmful effects on exploration systems. This paper presents the current perspective and implementation of dust knowledge management and integration, and mitigation technology development activities within NASA s Exploration Technology Development Program. This work is presented within the context of the Constellation Program s Integrated Lunar Dust Management Strategy. The Lunar Dust Mitigation Technology Development project has been implemented within the ETDP. Project scope and plans will be presented, along with a a perspective on lessons learned from Apollo and forensics engineering studies of Apollo hardware. This paper further outlines the scientific basis for lunar dust behavior, it s characteristics and potential effects, and surveys several potential strategies for its control and mitigation both for lunar surface operations and within the working volumes of a lunar outpost.

  13. Smart aircraft routing - a possibility for mitigation?

    NASA Astrophysics Data System (ADS)

    Mannstein, H.; Gierens, K.; Graf, K.; Waibel, A.; Meilinger, S.; Seifert, A.; Köhler, C.

    2009-12-01

    Air traffic affects the energy balance of the earth in various ways. Emission of CO2 with atmospheric residence times measured in decades contributes to the greenhouse effect as well as emission of nitrous oxides, with their impact on ozone and methane chemistry. Soot has a direct effect on the net radiation and, much more important, is involved in the production of contrails and the triggering of contrail cirrus, which can be visible for several hours. These artificial clouds are initiated when flying in sufficiently cold and moist air. In total, their net radiative forcing is of the same order of magnitude as the forcing by the emitted CO2. The impact of contrail cirrus on net radiation results from the conversion of ambient moisture in ice super-saturated regions into ice crystals and depends strongly on the conditions of the ambient radiation field. It ranges from a warming at night or over bright low clouds to cooling during daytime over dark surfaces like the ocean. For the time being these effects are not at all taken into consideration in aircraft routing: the production of contrails and contrail cirrus happens by chance. The dependency of the radiative forcing by contrail cirrus clouds on the weather conditions opens the possibility for mitigation: Avoiding warming (and perhaps also producing cooling) contrails and contrail cirrus by changes of the flight routes has the potential to reduce the man-made imbalance in radiative forcing. As contrails are produced only in 10%- 20% of the flown distances and only the warming contrails should be avoided, the impact on the traffic system is likely to be limited. The basic idea of the project ’Environmentally compatible flight route optimisation’, funded by the German Ministry for Research and Education is, to predict the time integrated radiative forcing of a potential contrail cirrus based on the information given by a weather forecast model. This information is used in relation to total forcing of the

  14. Climate adaptation as mitigation: the case of agricultural investments

    NASA Astrophysics Data System (ADS)

    Lobell, David B.; Baldos, Uris Lantz C.; Hertel, Thomas W.

    2013-03-01

    with respect to land rents, and the elasticity of substitution between land and non-land inputs. For assessing the mitigation costs, the elasticity of productivity with respect to investments in research and development is also very important. Overall, this study finds that broad-based efforts to adapt agriculture to climate change have mitigation co-benefits that, even when forced to shoulder the entire expense of adaptation, are inexpensive relative to many activities whose main purpose is mitigation. These results therefore challenge the current approach of most climate financing portfolios, which support adaptation from funds completely separate from—and often much smaller than—mitigation ones.

  15. Climate mitigation and the future of tropical landscapes.

    PubMed

    Thomson, Allison M; Calvin, Katherine V; Chini, Louise P; Hurtt, George; Edmonds, James A; Bond-Lamberty, Ben; Frolking, Steve; Wise, Marshall A; Janetos, Anthony C

    2010-11-16

    Land-use change to meet 21st-century demands for food, fuel, and fiber will depend on many interactive factors, including global policies limiting anthropogenic climate change and realized improvements in agricultural productivity. Climate-change mitigation policies will alter the decision-making environment for land management, and changes in agricultural productivity will influence cultivated land expansion. We explore to what extent future increases in agricultural productivity might offset conversion of tropical forest lands to crop lands under a climate mitigation policy and a contrasting no-policy scenario in a global integrated assessment model. The Global Change Assessment Model is applied here to simulate a mitigation policy that stabilizes radiative forcing at 4.5 W m(-2) (approximately 526 ppm CO(2)) in the year 2100 by introducing a price for all greenhouse gas emissions, including those from land use. These scenarios are simulated with several cases of future agricultural productivity growth rates and the results downscaled to produce gridded maps of potential land-use change. We find that tropical forests are preserved near their present-day extent, and bioenergy crops emerge as an effective mitigation option, only in cases in which a climate mitigation policy that includes an economic price for land-use emissions is in place, and in which agricultural productivity growth continues throughout the century. We find that idealized land-use emissions price assumptions are most effective at limiting deforestation, even when cropland area must increase to meet future food demand. These findings emphasize the importance of accounting for feedbacks from land-use change emissions in global climate change mitigation strategies.

  16. Climate mitigation and the future of tropical landscapes

    PubMed Central

    Thomson, Allison M.; Calvin, Katherine V.; Chini, Louise P.; Hurtt, George; Edmonds, James A.; Bond-Lamberty, Ben; Frolking, Steve; Wise, Marshall A.; Janetos, Anthony C.

    2010-01-01

    Land-use change to meet 21st-century demands for food, fuel, and fiber will depend on many interactive factors, including global policies limiting anthropogenic climate change and realized improvements in agricultural productivity. Climate-change mitigation policies will alter the decision-making environment for land management, and changes in agricultural productivity will influence cultivated land expansion. We explore to what extent future increases in agricultural productivity might offset conversion of tropical forest lands to crop lands under a climate mitigation policy and a contrasting no-policy scenario in a global integrated assessment model. The Global Change Assessment Model is applied here to simulate a mitigation policy that stabilizes radiative forcing at 4.5 W m−2 (approximately 526 ppm CO2) in the year 2100 by introducing a price for all greenhouse gas emissions, including those from land use. These scenarios are simulated with several cases of future agricultural productivity growth rates and the results downscaled to produce gridded maps of potential land-use change. We find that tropical forests are preserved near their present-day extent, and bioenergy crops emerge as an effective mitigation option, only in cases in which a climate mitigation policy that includes an economic price for land-use emissions is in place, and in which agricultural productivity growth continues throughout the century. We find that idealized land-use emissions price assumptions are most effective at limiting deforestation, even when cropland area must increase to meet future food demand. These findings emphasize the importance of accounting for feedbacks from land-use change emissions in global climate change mitigation strategies. PMID:20921413

  17. Glucosamine enhances body weight gain and reduces insulin response in mice fed chow diet but mitigates obesity, insulin resistance and impaired glucose tolerance in mice high-fat diet.

    PubMed

    Hwang, Ji-Sun; Park, Ji-Won; Nam, Moon-Suk; Cho, Hyeongjin; Han, Inn-Oc

    2015-03-01

    This study investigated the potential of glucosamine (GlcN) to affect body weight gain and insulin sensitivity in mice normal and at risk for developing diabetes. Male C57BL/6J mice were fed either chow diet (CD) or a high fat diet (HFD) and the half of mice from CD and HFD provided with a solution of 10% (w/v) GlcN. Total cholesterol and nonesterified free fatty acid levels were determined. Glucose tolerance test and insulin tolerance test were performed. HepG2 human hepatoma cells or differentiated 3T3-L1 adipocytes were stimulated with insulin under normal (5 mM) or high glucose (25 mM) conditions. Effect of GlcN on 2-deoxyglucose (2-DG) uptake was determined. JNK and Akt phosphorylation and nucleocytoplasmic protein O-GlcNAcylation were assayed by Western blotting. GlcN administration stimulated body weight gain (6.58±0.82 g vs. 11.1±0.42 g), increased white adipose tissue fat mass (percentage of bodyweight, 3.7±0.32 g vs. 5.61±0.34 g), and impaired the insulin response in livers of mice fed CD. However, GlcN treatment in mice fed HFD led to reduction of body weight gain (18.02±0.66 g vs. 16.22±0.96 g) and liver weight (2.27±0.1 vs. 1.85±0.12 g). Furthermore, obesity-induced insulin resistance and impaired Akt insulin signaling in the liver were alleviated by GlcN administration. GlcN inhibited the insulin response under low (5 mM) glucose conditions, whereas it restored the insulin response for Akt phosphorylation under high (25 mM) glucose conditions in HepG2 and 3T3-L1 cells. Uptake of 2-DG increased upon GlcN treatment under 5 mM glucose compared to control, whereas insulin-stimulated 2-DG uptake decreased under 5 mM and increased under 25 mM glucose in differentiated 3T3-L1 cells. Our results show that GlcN increased body weight gain and reduced the insulin response for glucose maintenance when fed to normal CD mice, whereas it alleviated body weight gain and insulin resistance in HFD mice. Therefore, the current data support the integrative

  18. Compensatory Mitigation Rule Final Environmental Assessment

    EPA Pesticide Factsheets

    EA performed to determine the costs resulting from implementation of the Compensatory Mitigation Rule and the extent to which the rule changes aggregate mitigation costs borne by permittees and Corps administrative burdens and associated costs.

  19. Compensatory Mitigation Rule Draft Environmental Assessment

    EPA Pesticide Factsheets

    Draft Compensatory Mitigation Rule intended to promote regulatory efficiency by establishing standards and criteria that would apply to compensatory mitigation required for DA permits issued under Section 404 of the Clean Water Act.

  20. Mountain State Mitigation Credit Company (banker)

    EPA Pesticide Factsheets

    MSMCC is a mitigation bank working to restore Buffalo Creek. Buffalo Creek watershed will be successfully restored from the headwaters down to establish complete “watershed restoration” that is consistent with the Mitigation Rule.

  1. ITER Disruption Mitigation System Design

    NASA Astrophysics Data System (ADS)

    Rasmussen, David; Lyttle, M. S.; Baylor, L. R.; Carmichael, J. R.; Caughman, J. B. O.; Combs, S. K.; Ericson, N. M.; Bull-Ezell, N. D.; Fehling, D. T.; Fisher, P. W.; Foust, C. R.; Ha, T.; Meitner, S. J.; Nycz, A.; Shoulders, J. M.; Smith, S. F.; Warmack, R. J.; Coburn, J. D.; Gebhart, T. E.; Fisher, J. T.; Reed, J. R.; Younkin, T. R.

    2015-11-01

    The disruption mitigation system for ITER is under design and will require injection of up to 10 kPa-m3 of deuterium, helium, neon, or argon material for thermal mitigation and up to 100 kPa-m3 of material for suppression of runaway electrons. A hybrid unit compatible with the ITER nuclear, thermal and magnetic field environment is being developed. The unit incorporates a fast gas valve for massive gas injection (MGI) and a shattered pellet injector (SPI) to inject a massive spray of small particles, and can be operated as an SPI with a frozen pellet or an MGI without a pellet. Three ITER upper port locations will have three SPI/MGI units with a common delivery tube. One equatorial port location has space for sixteen similar SPI/MGI units. Supported by US DOE under DE-AC05-00OR22725.

  2. The battle against multi-resistant strains: Renaissance of antimicrobial essential oils as a promising force to fight hospital-acquired infections.

    PubMed

    Warnke, Patrick H; Becker, Stephan T; Podschun, Rainer; Sivananthan, Sureshan; Springer, Ingo N; Russo, Paul A J; Wiltfang, Joerg; Fickenscher, Helmut; Sherry, Eugene

    2009-10-01

    Hospital-acquired infections and antibiotic-resistant bacteria continue to be major health concerns worldwide. Particularly problematic is methicillin-resistant Staphylococcus aureus (MRSA) and its ability to cause severe soft tissue, bone or implant infections. First used by the Australian Aborigines, Tea tree oil and Eucalyptus oil (and several other essential oils) have each demonstrated promising efficacy against several bacteria and have been used clinically against multi-resistant strains. Several common and hospital-acquired bacterial and yeast isolates (6 Staphylococcus strains including MRSA, 4 Streptococcus strains and 3 Candida strains including Candida krusei) were tested for their susceptibility for Eucalyptus, Tea tree, Thyme white, Lavender, Lemon, Lemongrass, Cinnamon, Grapefruit, Clove Bud, Sandalwood, Peppermint, Kunzea and Sage oil with the agar diffusion test. Olive oil, Paraffin oil, Ethanol (70%), Povidone iodine, Chlorhexidine and hydrogen peroxide (H(2)O(2)) served as controls. Large prevailing effective zones of inhibition were observed for Thyme white, Lemon, Lemongrass and Cinnamon oil. The other oils also showed considerable efficacy. Remarkably, almost all tested oils demonstrated efficacy against hospital-acquired isolates and reference strains, whereas Olive and Paraffin oil from the control group produced no inhibition. As proven in vitro, essential oils represent a cheap and effective antiseptic topical treatment option even for antibiotic-resistant strains as MRSA and antimycotic-resistant Candida species.

  3. Relationship between population density of attorneys and prevalence of methicillin-resistant Staphylococcus aureus: is medical-legal pressure on physicians a driving force behind the development of antibiotic resistance?

    PubMed

    Sakoulas, George; Wormser, Gary P; Visintainer, Paul; Aronow, Wilbert S; Nadelman, Robert B

    2009-01-01

    We performed a hypothesis-generating study evaluating the perceived threat of lawsuits among physicians and methicillin resistance in Staphylococcus aureus. We found a correlation between the prevalence of methicillin resistance among clinical S. aureus isolates and both antibiotic prescriptions per capita and density of attorneys in countries in Europe and North America. We did not find a correlation between prevalence of methicillin resistance and physician density. Further investigation is warranted to study whether physicians' perceived fear of lawsuits, of which attorney density may be a crude surrogate marker, results in antibiotic prescription practices that contribute to the emergence of antimicrobial resistance among virulent pathogens such as S. aureus, with global implications on the ethics of the delivery of quality health care to all members of society.

  4. Fish and Wildlife Mitigation Plan

    DTIC Science & Technology

    1979-07-01

    Sacramento River Bank Protection Project 3 Environmental Impact of Construction of the First Phase 6 Determination of Mitigation Needs 7 Analysis 8...be acquired for habitat restoration for fish and wildlife purposes to offset the impact of construction of the First Phase of the Sacramento River...set forth, along with other data necessary for project authorization, in a report submitted to the Congress by the construction agency. Construction

  5. Hypoxia, Monitoring, and Mitigation System

    DTIC Science & Technology

    2015-08-01

    Document CDRL A001-3 Revision: Original Date: Aug 2015 Page: 1 of 43 Document Title: HAMS II Quarterly Progress Report...unlimited. 13. SUPPLEMENTARY NOTES The original document contains color images. 14. ABSTRACT The Hypoxia Monitoring, Alert and Mitigation System...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Document CDRL A001-3 Revision: Original Date: Aug 2015 Page: 2

  6. 7 CFR 652.39 - Mitigating factors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Mitigating factors. 652.39 Section 652.39 Agriculture... factors. In considering whether to decertify, the period of decertification, and scope of decertification, the deciding official will take into consideration any mitigating factors. Examples of mitigating...

  7. 7 CFR 652.39 - Mitigating factors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Mitigating factors. 652.39 Section 652.39 Agriculture... factors. In considering whether to decertify, the period of decertification, and scope of decertification, the deciding official will take into consideration any mitigating factors. Examples of mitigating...

  8. Mitigation of wildfire risk by homeowners

    Treesearch

    Hannah Brenkert; Patricia Champ; Nicholas Flores

    2005-01-01

    In-depth interviews conducted with homeowners in Larimer County's Wildland-Urban Interface revealed that homeowners face difficult decisions regarding the implementation of wildfire mitigation measures. Perceptions of wildfire mitigation options may be as important as perceptions of wildfire risk in determining likelihood of implementation. These mitigation...

  9. 23 CFR 710.513 - Environmental mitigation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Environmental mitigation. 710.513 Section 710.513...-WAY AND REAL ESTATE Property Acquisition Alternatives § 710.513 Environmental mitigation. (a) The... appropriate environmental mitigation is an eligible cost under the Federal-aid program. FHWA participation...

  10. 23 CFR 710.513 - Environmental mitigation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 23 Highways 1 2013-04-01 2013-04-01 false Environmental mitigation. 710.513 Section 710.513...-WAY AND REAL ESTATE Property Acquisition Alternatives § 710.513 Environmental mitigation. (a) The... appropriate environmental mitigation is an eligible cost under the Federal-aid program. FHWA participation in...

  11. 23 CFR 710.513 - Environmental mitigation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 23 Highways 1 2012-04-01 2012-04-01 false Environmental mitigation. 710.513 Section 710.513...-WAY AND REAL ESTATE Property Acquisition Alternatives § 710.513 Environmental mitigation. (a) The... appropriate environmental mitigation is an eligible cost under the Federal-aid program. FHWA participation in...

  12. 23 CFR 710.513 - Environmental mitigation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 23 Highways 1 2011-04-01 2011-04-01 false Environmental mitigation. 710.513 Section 710.513...-WAY AND REAL ESTATE Property Acquisition Alternatives § 710.513 Environmental mitigation. (a) The... appropriate environmental mitigation is an eligible cost under the Federal-aid program. FHWA participation in...

  13. 50 CFR 216.204 - Mitigation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Mitigation. 216.204 Section 216.204... U.S. Beaufort Sea § 216.204 Mitigation. The activity identified in § 216.200(a) must be conducted in... their habitats. When conducting operations identified in § 216.200, the mitigation measures contained in...

  14. 24 CFR 203.501 - Loss mitigation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Loss mitigation. 203.501 Section... FAMILY MORTGAGE INSURANCE Servicing Responsibilities General Requirements § 203.501 Loss mitigation... conditions and requirements for the appropriate use of these loss mitigation actions, concerning such matters...

  15. Down force calibration stand test report

    SciTech Connect

    BOGER, R.M.

    1999-08-13

    The Down Force Calibration Stand was developed to provide an improved means of calibrating equipment used to apply, display and record Core Sample Truck (CST) down force. Originally, four springs were used in parallel to provide a system of resistance that allowed increasing force over increasing displacement. This spring system, though originally deemed adequate, was eventually found to be unstable laterally. For this reason, it was determined that a new method for resisting down force was needed.

  16. Mitigation alternatives for L Lake

    SciTech Connect

    Moore, D.B.

    1988-11-03

    The current condition of L Lake/Steel Creek was summarized in a report to SCDHEC in June 1988 which reported that the L Lake and Steel Creek ecosystems were adequately developing towards balanced biological communities. If mitigation for L Lake inputs, specifically temperature and nutrients, are required, several viable alternatives are available. A report prepared by Spencer in 1986 discusses the various options available for cooling L-Reactor discharges. In effect, a small cooling tower is the only realistic solution to reducing effluent temperatures. Nutrient mitigation can take several approaches including upstream sewage treatment, hypolimnetic withdrawal, dilution of input water by Par Pond water, precipitation of nutrients, and sediment oxidation. None of these systems would influence the thermal regime, but would significantly reduce nutrient input into the system. One beneficial use of L-Lake thermal effluents is algaculture, the production of useful algae. A document prepared in 1988 concludes that algaculture is a technically and economically feasible mitigation alternative for L Lake and could allow L Lake to be handled under Section 318 of the Clean Water Act.

  17. Mitigation of Lunar Dust Adhesion by Surface Treatment

    NASA Astrophysics Data System (ADS)

    Dove, A.; Wang, X.; Robertson, S. H.; Horanyi, M.; Devaud, J.; Crowder, M.; Lawitzke, A.

    2009-12-01

    Dust has been recognized as one of the greatest hazards in continued lunar exploration. Thus, it is crucial to develop dust mitigation techniques that will minimize both the damages done to hardware and the dangers posed to humans working on the Moon. Passive mitigation techniques, which modify the surface of a material prior to dust exposure, will aid in repelling dust or reducing adhesion for easier dust removal. Our experiments use various surfaces (black Kapton (polymide), quartz, and silicon) that have been treated to have low surface energies by a Ball Aerospace and Technologies Corp. proprietary surface treatment technique. We use a centrifugal force detachment method to measure the total adhesive force acting between < 25 µm JSC-1 lunar simulant grains and these surfaces, both untreated and treated, in vacuum. Results indicate that the treated surfaces show significant improvement; dust is removed from treated black Kapton with about 4% of the force required for untreated black Kapton, while treated quartz and silicon show about a 50% reduction in force. Further tests will be conducted on additional surfaces, such as stainless steel and polycarbonate, and with different size fractions of JSC-1 in order to evaluate the role of dust grain size on adhesion. Because the Moon’s surface is directly exposed to solar UV radiation, we will also measure adhesion on surfaces that have previously been UV-irradiated.

  18. Climate mitigation and the future of tropical landscapes

    SciTech Connect

    Thomson, Allison M.; Calvin, Katherine V.; Chini, Louise Parsons; Hurtt, George; Edmonds, James A.; Bond-Lamberty, Benjamin; Frolking, Steve; Wise, Marshall A.; Janetos, Anthony C.

    2010-11-16

    Land use change to meet 21st Century demands for food, fuel, and fiber will occur in the context of both a changing climate as well as societal efforts to mitigate climate change. This changing natural and human environment will have large consequences for forest resources, terrestrial carbon storage and emissions, and food and energy crop production over the next century. Any climate change mitigation policies enacted will change the environment under which land-use decisions are made and alter global land use change patterns. Here we use the GCAM integrated assessment model to explore how climate mitigation policies that achieve a climate stabilization at 4.5 W m-2 radiative forcing in 2100 and value carbon in terrestrial ecosystems interact with future agricultural productivity and food and energy demands to influence land use in the tropics. The regional land use results are downscaled from GCAM regions to produce gridded maps of tropical land use change. We find that tropical forests are preserved only in cases where a climate mitigation policy that values terrestrial carbon is in place, and crop productivity growth continues throughout the century. Crop productivity growth is also necessary to avoid large scale deforestation globally and enable the production of bioenergy crops. The terrestrial carbon pricing assumptions in GCAM are effective at avoiding deforestation even when cropland must expand to meet future food demand.

  19. Planning Tools For Seismic Risk Mitigation. Rules And Applications

    SciTech Connect

    De Paoli, Rosa Grazia

    2008-07-08

    Recently, Italian urban planning research in the field of seismic risk mitigation are renewing. In particular, it promotes strategies that integrate urban rehabilitation and aseismic objectives, and also politicizes that are directed to revitalizes urban systems, coupling physical renewal and socio-economic development.In Italy the first law concerning planning for seismic mitigation dates back 1974, the law n. 64 'Regulation for buildings with particular rules for the seismic areas' where the rules for buildings in seismic areas concerning also the local hazard. This law, in fact, forced the municipalities to acquire, during the formation of the plans, a preventive opinion of compatibility between planning conditions and geomorphology conditions of the territory. From this date the conviction that the seismic risk must be considered inside the territorial planning especially in terms of strategies of mitigation has been strengthened.The town planners have started to take an interest in seismic risk in the [80]s when the Irpinia's earthquake took place. The researches developed after this earthquake have established that the principal cause of the collapse of buildings are due to from the wrong location of urban settlements (on slopes or crowns) After Irpinia's earthquake the first researches on seismic risk mitigation, in particular on the aspects related to the hazards and to the urban vulnerability were made.

  20. Ice Detection and Mitigation Device

    NASA Technical Reports Server (NTRS)

    Gambino, Richard J. (Inventor); Gouldstone, Christopher (Inventor); Gutleber, Jonathan (Inventor); Hubble, David (Inventor); Trelewicz, Jason (Inventor)

    2016-01-01

    A method for deicing an aerostructure includes driving a sensing current through a heater element coated to an aerostructure, the heater element having a resistance that is temperature dependent. A resistance of the heater element is monitored. It is determined whether there is icing at the heater element using the monitored resistance of the heater element. A melting current is driven through the heater element when it is determined that there is icing at the heater element.

  1. Pattern collapse mitigation strategies for EUV lithography

    NASA Astrophysics Data System (ADS)

    Goldfarb, Dario L.; Bruce, Robert L.; Bucchignano, James J.; Klaus, David P.; Guillorn, Michael A.; Wu, Chunghsi J.

    2012-03-01

    In this study, a comprehensive approach towards assessing pattern collapse challenges and solutions for Extreme Ultraviolet Lithography (EUV) resists beyond the 14nm node is undertaken. The fundamental forces that drive pattern deformation are reassessed in order to propose a generalized design criterion for EUV photoresists and aqueous surfactanated rinses. Furthermore, ultimate pattern collapse solutions such as solvent drying utilizing pressurized fluids (supercritical CO2) are exemplified for sub-60nm pitch EUV patterning. In parallel, alternative EUV integration schemes that use a metal-based hardmask (MHM) are studied using a specifically tailored self-assembled monolayer (SAM) to prevent delamination-driven pattern collapse due to resist-hardmask interfacial adhesion failure. Finally, the marginal image transfer of 40nm pitched L/S of ultrathin EUV resist into a SiARC-underlayer stack appears to be gated by the EUV resist resolution limit and the reduced film thickness budget. An alternative method for achieving improved postetch line width roughness (LWR) with an ultrathin MHM-based integration scheme is herein demonstrated.

  2. Quantitative goals for a 222Rn multimedia mitigation plan.

    PubMed

    Newton, B M; Watson, J E; Cote, R A

    2001-11-01

    The U.S. Environmental Protection Agency's revised proposed 222Rn in drinking water regulation gives states or individual community water systems the option of compliance with the maximum contaminant level or compliance with the higher, alternate maximum contaminant level accompanied by the implementation of a multimedia mitigation plan. If states or water suppliers choose to comply with the alternate maximum contaminant level, the health risk reduction achieved by multimedia mitigation programs must be equal to or greater than the health risk reduction that would be achieved by compliance with the maximum contaminant level rather than the alternate maximum contaminant level. We have developed a method to determine quantitative goals for mitigating existing homes and building new 222Rn-resistant homes to achieve a health risk reduction to the public equivalent to the health risk differential between alternate maximum contaminant level and maximum contaminant level compliance. This method can be applied to an entire state, a portion of a state, or to an individual water supplier. The method was applied to North Carolina, and it was concluded that, over time, the health risk reduction achievable from alternate maximum contaminant level compliance and the implementation of a multimedia mitigation program would be much greater than from compliance with the maximum contaminant level.

  3. Near-Term Climate Mitigation by Short-Lived Forcers

    SciTech Connect

    Smith, Steven J.; Mizrahi, Andrew H.

    2013-08-12

    Emissions reductions focused on anthropogenic climate forcing agents with relatively short atmospheric lifetimes such as methane (CH4) and black carbon (BC) have been suggested as a strategy to reduce the rate of climate change over the next several decades. We find that reductions of methane and BC would likely have only a modest impact on near-term climate warming. Even with maximally feasible reductions phased in from 2015 to 2035, global mean temperatures in 2050 are reduced by 0.16 °C, with an uncertainty range of 0.04-0.36°C, with the high end of this range only possible if total historical aerosol forcing is small. More realistic mitigation scenarios would likely provide a smaller climate benefit. The climate benefits from targeted reductions in short-lived forcing agents are smaller than previously estimated and are not substantially different in magnitude from the benefits due to a comprehensive climate policy.

  4. A web-based tool for ranking landslide mitigation measures

    NASA Astrophysics Data System (ADS)

    Lacasse, S.; Vaciago, G.; Choi, Y. J.; Kalsnes, B.

    2012-04-01

    As part of the research done in the European project SafeLand "Living with landslide risk in Europe: Assessment, effects of global change, and risk management strategies", a compendium of structural and non-structural mitigation measures for different landslide types in Europe was prepared, and the measures were assembled into a web-based "toolbox". Emphasis was placed on providing a rational and flexible framework applicable to existing and future mitigation measures. The purpose of web-based toolbox is to assist decision-making and to guide the user in the choice of the most appropriate mitigation measures. The mitigation measures were classified into three categories, describing whether the mitigation measures addressed the landslide hazard, the vulnerability or the elements at risk themselves. The measures considered include structural measures reducing hazard and non-structural mitigation measures, reducing either the hazard or the consequences (or vulnerability and exposure of elements at risk). The structural measures include surface protection and control of surface erosion; measures modifying the slope geometry and/or mass distribution; measures modifying surface water regime - surface drainage; measures mo¬difying groundwater regime - deep drainage; measured modifying the mechanical charac¬teristics of unstable mass; transfer of loads to more competent strata; retaining structures (to modify slope geometry and/or to transfer stress to compe¬tent layer); deviating the path of landslide debris; dissipating the energy of debris flows; and arresting and containing landslide debris or rock fall. The non-structural mitigation measures, reducing either the hazard or the consequences: early warning systems; restricting or discouraging construction activities; increasing resistance or coping capacity of elements at risk; relocation of elements at risk; sharing of risk through insurance. The measures are described in the toolbox with fact sheets providing a

  5. Labor Force

    ERIC Educational Resources Information Center

    Occupational Outlook Quarterly, 2012

    2012-01-01

    The labor force is the number of people ages 16 or older who are either working or looking for work. It does not include active-duty military personnel or the institutionalized population, such as prison inmates. Determining the size of the labor force is a way of determining how big the economy can get. The size of the labor force depends on two…

  6. Prediction and mitigation of disruptions in ASDEX Upgrade

    NASA Astrophysics Data System (ADS)

    Pautasso, G.; Egorov, S.; Tichmann, Ch; Fuchs, J. C.; Herrmann, A.; Maraschek, M.; Mast, F.; Mertens, V.; Perchermeier, I.; Windsor, C. G.; Zehetbauer, T.; ASDEX Upgrade Team

    2001-03-01

    Disruptions in tokamaks are instabilities events which can damage the machine components. The avoidance and mitigation of these events is desirable in present machines as well as in Next Step devices (such as ITER). A neural network has been developed to predict the occurrence of disruptions caused by edge cooling mechanisms in ASDEX Upgrade. The network works reliably and is able to predict the majority (85%) of the disruptions. The neural network has been trained to predict the time interval up to the disruption and this makes it suitable to be used on-line either to avoid disruptions (by means of auxiliary heating and reduction of gas puffing) or to mitigate the unavoidable ones. For this last purpose, a solid pellet injector has been developed and tested; the injected impurity pellets have been shown to reduce the vertical forces and the conductive fluxes to the divertor.

  7. A more productive, but different, ocean after mitigation

    NASA Astrophysics Data System (ADS)

    John, Jasmin G.; Stock, Charles A.; Dunne, John P.

    2015-11-01

    Reversibility studies suggest a lagged recovery of global mean sea surface temperatures after mitigation, raising the question of whether a similar lag is likely for marine net primary production (NPP). Here we assess NPP reversibility with a mitigation scenario in which projected Representative Concentration Pathway (RCP) 8.5 forcings are applied out to 2100 and then reversed over the course of the following century in a fully coupled carbon-climate Earth System Model. In contrast to the temperature lag, we find a rapid increase in global mean NPP, including an overshoot to values above contemporary means. The enhanced NPP arises from a transient imbalance between the cooling surface ocean and continued warming in subsurface waters, which weakens upper ocean density gradients, resulting in deeper mixing and enhanced surface nitrate. We also find a marine ecosystem regime shift as persistent silicate depletion results in increased prevalence of large, non-diatom phytoplankton.

  8. Smart disaster mitigation in Thailand

    NASA Astrophysics Data System (ADS)

    Aimmanee, S.; Ekkawatpanit, C.; Asanuma, H.

    2016-04-01

    Thailand is notoriously exposed to several natural disasters, from heavy thunder storms to earthquakes and tsunamis, since it is located in the tropical area and has tectonic cracks underneath the ground. Besides these hazards flooding, despite being less severe, occurs frequently, stays longer than the other disasters, and affects a large part of the national territory. Recently in 2011 have also been recorded the devastating effects of major flooding causing the economic damages and losses around 50 billion dollars. Since Thailand is particularly exposed to such hazards, research institutions are involved in campaigns about monitoring, prevention and mitigation of the effects of such phenomena, with the aim to secure and protect human lives, and secondly, the remarkable cultural heritage. The present paper will first make a brief excursus on the main Thailand projects aimed at the mitigation of natural disasters, referring to projects of national and international relevance, being implemented, such as the ESCAP1999 (flow regime regulation and water conservation). Adaptable devices such as foldable flood barriers and hydrodynamically supported temporary banks have been utilized when flooding. In the second part of the paper, will be described some new ideas concerning the use of smart and biomimicking column structures capable of high-velocity water interception and velocity detection in the case of tsunami. The pole configuration is composite cylindrical shell structure embedded with piezoceramic sensor. The vortex shedding of the flow around the pole induces the vibration and periodically strains the piezoelectric element, which in turn generates the electrical sensorial signal. The internal space of the shell is filled with elastic foam to enhance the load carrying capability due to hydrodynamic application. This more rigid outer shell inserted with soft core material resemble lotus stem in nature in order to prolong local buckling and ovalization of column

  9. Mitigation of structureborne noise nuisance

    NASA Astrophysics Data System (ADS)

    Ko, Wing P.

    2005-09-01

    This paper presents a noise complaint case which was solved by me a few years ago in Hong Kong. A newlywed couple in the residential unit complained to the Government that the noise emitted from the pump room directly beneath their unit was very annoying, especially in the night-time period. The owner of the building was then required by the Government to mitigate the noise to the night-time statutory noise requirement within 30 days, otherwise he would be prosecuted. Ideally, the structureborne noise from the pump room could be effectively mitigated by installation of floating slab and vibration isolators under the pumps. Also, the water tanks and water pipes were required to be isolated from the walls and floor. However, this work was impossible to be completed within 30 days to stop the prosecution. Water supply to the above residents would be seriously interrupted during the construction period. As the only noise parameter of the statutory requirement was 30 minute A-weighted Leq, the most effective and practical way in this exigent situation was to reduce the pump operation time within any 30 minute period to decrease the Leq values. In addition, the water pipes and pumps were also required to be isolated from the walls and floor with resilient materials to break the vibration channels. These noise mitigation measures were successfully applied to the pump room before the end of the 30 days. Finally, the noise levels inside the complainant's unit were found to meet the statutory requirement. The noise complaint case was then closed by the Government.

  10. Conceptual Study on Air Ingress Mitigation for VHTRs

    SciTech Connect

    Chang H. Oh; Eung S. Kim

    2012-09-01

    An air-ingress accident followed by a pipe break is considered as a critical event for a very high temperature gas-cooled reactor (VHTR) safety. Following helium depressurization, it is anticipated that unless countermeasures are taken, air will enter the core through the break leading to oxidation of the in-core graphite structure. Thus, without mitigation features, this accident might lead to severe exothermic chemical reactions of graphite and oxygen depending on the accident scenario and the design. Under extreme circumstances, a loss of core structural integrity may occur and lead to a detrimental situation for the VHTR safety. This paper discusses various air-ingress mitigation concepts applicable for the VHTRs. The study begins with identifying important factors (or phenomena) associated with the air-ingress accident using a root-cause analysis. By preventing main causes of the important events identified in the root-cause diagram, the basic air-ingress mitigation ideas were conceptually developed. Among them, two concepts were finally evaluated as effective candidates. One concept is to inject helium into the lower plenum which is a direct in-vessel helium injection. The other concept is to enclose the reactor with a non-pressure boundary consisting of an opening at the bottom, which is an ex-vessel enclosure boundary. Computational fluid dynamics (CFD) methods were used to validate these concepts. As a result, it was shown that both concepts can effectively mitigate the air-ingress process. In the first concept, the injected helium replaces the air in the core and the lower plenum upper part by buoyancy force because of its low density. It prevented air from moving into the reactor core showing great potential for mitigating graphite oxidation in the core. In the second concept, the air-ingress rate is controlled by molecular diffusion through the opening at the enclosure bottom after depressurization. Some modified reactor cavity design is expected to

  11. Reassessing Biological Threats: Implications for Cooperative Mitigation Strategies.

    PubMed

    Galloway, Summer Elise; Petzing, Stephanie Rachel; Young, Catharine Grace

    2015-01-01

    Multiple factors ranging from globalization to ecosystem disruption are presenting the global community with evolving biological threats to local, national, and global security that reach beyond the realm of traditional bioweapon threats. As a result, mitigation strategies have adapted necessarily to the increased diversity of biological threats. In general, response and preparedness strategies have largely shifted from being primarily reactive to traditional biological weapons to more proactive in nature. In this review, we briefly explore biological threats through a wider aperture, to embrace a greater appreciation of viral pathogens, antimicrobial resistance, and agricultural pathogens, and their potential to cause civil, economic, and political devastation. In addition, we discuss current mitigation strategies codified by the Global Health Security Agenda and the One Health paradigm as well as some of the available tools to assist with their sustainable implementation.

  12. Reassessing Biological Threats: Implications for Cooperative Mitigation Strategies

    PubMed Central

    Galloway, Summer Elise; Petzing, Stephanie Rachel; Young, Catharine Grace

    2015-01-01

    Multiple factors ranging from globalization to ecosystem disruption are presenting the global community with evolving biological threats to local, national, and global security that reach beyond the realm of traditional bioweapon threats. As a result, mitigation strategies have adapted necessarily to the increased diversity of biological threats. In general, response and preparedness strategies have largely shifted from being primarily reactive to traditional biological weapons to more proactive in nature. In this review, we briefly explore biological threats through a wider aperture, to embrace a greater appreciation of viral pathogens, antimicrobial resistance, and agricultural pathogens, and their potential to cause civil, economic, and political devastation. In addition, we discuss current mitigation strategies codified by the Global Health Security Agenda and the One Health paradigm as well as some of the available tools to assist with their sustainable implementation. PMID:26649289

  13. Orbiting space debris: Dangers, measurement and mitigation

    NASA Astrophysics Data System (ADS)

    McNutt, Ross T.

    1992-06-01

    Space debris is a growing environmental problem. Accumulation of objects in earth orbit threatens space systems through the possibility of collisions and runaway debris multiplication. The amount of debris in orbit is uncertain due to the lack of information on the population of debris between 1 and 10 centimeters diameter. Collisions with debris even smaller than 1 cm can be catastrophic due to the high orbital velocities involved. Research efforts are under way at NASA, United States Space Command and the Air Force Phillips Laboratory to detect and catalog the debris population in near-earth space. Current international and national laws are inadequate to control the proliferation of space debris. Space debris is a serious problem with large economic, military, technical and diplomatic components. Actions need to be taken now to: determine the full extent of the orbital debris problem; accurately predict the future evolution of the debris population; decide the extent of the debris mitigation procedures required; implement these policies on a global basis via an international treaty. Action must be initiated now, before the loss of critical space systems such as the space shuttle or the space station.

  14. Orbiting space debris: Dangers, measurement, and mitigation

    NASA Astrophysics Data System (ADS)

    McNutt, Ross T.

    1992-01-01

    Space debris is a growing environmental problem. Accumulation of objects in Earth orbit threatens space systems through the possibility of collisions and runaway debris multiplication. The amount of debris in orbit is uncertain due to the lack of information on the population of debris between 1 and 10 centimeters diameter. Collisions with debris even smaller than 1 cm can be catastrophic due to the high orbital velocities involved. Research efforts are under way at NASA, Unites States Space Command and the Air Force Phillips Laboratory to detect and catalog the debris population in near-Earth space. Current international and national laws are inadequate to control the proliferation of space debris. Space debris is a serious problem with large economic, military, technical, and diplomatic components. Actions need to be taken now for the following reasons: determine the full extent of the orbital debris problem; accurately predict the future evolution of the debris population; decide the extent of the debris mitigation procedures required; implement these policies on a global basis via an international treaty. Action must be initiated now, before the the loss of critical space systems such as the Space Shuttle or the Space Station.

  15. ENHANCED PRACTICAL PHOTOSYNTHETIC CO2 MITIGATION

    SciTech Connect

    Dr. David J. Bayless; Dr. Morgan Vis; Dr. Gregory Kremer; Dr. Michael Prudich; Dr. Keith Cooksey; Dr. Jeff Muhs

    2001-01-16

    This is the first quarterly report of the project Enhanced Practical Photosynthetic CO{sub 2} Mitigation. The official project start date, 10/02/2000, was delayed until 10/31/2000 due to an intellectual property dispute that was resolved. However, the delay forced a subsequent delay in subcontracting with Montana State University, which then delayed obtaining a sampling permit from Yellowstone National Park. However, even with these delays, the project moved forward with some success. Accomplishments for this quarter include: Culturing of thermophilic organisms from Yellowstone; Testing of mesophilic organisms in extreme CO{sub 2} conditions; Construction of a second test bed for additional testing; Purchase of a total carbon analyzer dedicated to the project; Construction of a lighting container for Oak Ridge National Laboratory optical fiber testing; Modified lighting of existing test box to provide more uniform distribution; Testing of growth surface adhesion and properties; Experimentation on water-jet harvesting techniques; and Literature review underway regarding uses of biomass after harvesting. Plans for next quarter's work and an update on the project's web page are included in the conclusions.

  16. Partial eigenvalue assignment for structural damage mitigation

    NASA Astrophysics Data System (ADS)

    Ashokkumar, Chimpalthradi R.; Iyengar, N. G. R.

    2011-01-01

    In partial eigenvalue assignment, not all eigenvalues of the open loop system matrix are modified through a multiple input state or output feedback controller. This freedom available to assign selected eigenvalues of the closed loop system matrix has been widely used in design contexts such as to eliminate spillover effects in structural control problems. Similar approach is also required to modify damping and/or stiffness characteristics in selected eigenmodes of a damaged structure. When an external force acts on the damaged structure, partial eigenvalue assignment in this fashion will attempt to use minimal control effort and keep the structure active with safe operation. In this paper, a new approach to partial eigenvalue assignment and its application to structural damage mitigation are presented. A three mass spring-damper model with damage in one of the springs is illustrated with damping modifications at specific eigenmodes. The procedure is repeated for a second example, which is a cantilever beam modeled using two inputs and 10 state variables.

  17. WHC natural phenomena hazards mitigation implementation plan

    SciTech Connect

    Conrads, T.J.

    1996-09-11

    Natural phenomena hazards (NPH) are unexpected acts of nature which pose a threat or danger to workers, the public or to the environment. Earthquakes, extreme winds (hurricane and tornado),snow, flooding, volcanic ashfall, and lightning strike are examples of NPH at Hanford. It is the policy of U.S. Department of Energy (DOE) to design, construct and operate DOE facilitiesso that workers, the public and the environment are protected from NPH and other hazards. During 1993 DOE, Richland Operations Office (RL) transmitted DOE Order 5480.28, ``Natural Phenomena Hazards Mitigation,`` to Westinghouse Hanford COmpany (WHC) for compliance. The Order includes rigorous new NPH criteria for the design of new DOE facilities as well as for the evaluation and upgrade of existing DOE facilities. In 1995 DOE issued Order 420.1, ``Facility Safety`` which contains the same NPH requirements and invokes the same applicable standards as Order 5480.28. It will supersede Order 5480.28 when an in-force date for Order 420.1 is established through contract revision. Activities will be planned and accomplished in four phases: Mobilization; Prioritization; Evaluation; and Upgrade. The basis for the graded approach is the designation of facilities/structures into one of five performance categories based upon safety function, mission and cost. This Implementation Plan develops the program for the Prioritization Phase, as well as an overall strategy for the implemention of DOE Order 5480.2B.

  18. 3(omega) Damage: Growth Mitigation

    SciTech Connect

    Kozlowski, M; Demos, S; Wu, Z-L; Wong, J; Penetrante, B; Hrubesh, L

    2001-02-22

    The design of high power UV laser systems is limited to a large extent by the laser-initiated damage performance of transmissive fused silica optical components. The 3{omega} (i.e., the third harmonic of the primary laser frequency) damage growth mitigation LDRD effort focused on understanding and reducing the rapid growth of laser-initiated surface damage on fused silica optics. Laser-initiated damage can be discussed in terms of two key issues: damage initiated at some type of precursor and rapid damage growth of the damage due to subsequent laser pulses. The objective of the LDRD effort has been the elucidation of laser-induced damage processes in order to quantify and potentially reduce the risk of damage to fused silica surfaces. The emphasis of the first two years of this effort was the characterization and reduction of damage initiation. In spite of significant reductions in the density of damage sites on polished surfaces, statistically some amount of damage initiation should always be expected. The early effort therefore emphasized the development of testing techniques that quantified the statistical nature of damage initiation on optical surfaces. This work led to the development of an optics lifetime modeling strategy that has been adopted by the NIF project to address damage-risk issues. During FY99 interest shifted to the damage growth issue which was the focus of the final year of this project. The impact of the remaining damage sites on laser performance can be minimized if the damage sites did not continue to grow following subsequent illumination. The objectives of the final year of the LDRD effort were to apply a suite of state-of-the-art characterization tools to elucidate the nature of the initiated damage sites, and to identify a method that effectively mitigates further damage growth. Our specific goal is to understand the cause for the rapid growth of damage sites so that we can develop and apply an effective means to mitigate it. The

  19. Tsunami mitigation - redistribution of energy

    NASA Astrophysics Data System (ADS)

    Kadri, Usama

    2017-04-01

    Tsunamis are water waves caused by the displacement of a large volume of water, in the deep ocean or a large lake, following an earthquake, landslide, underwater explosion, meteorite impacts, or other violent geological events. On the coastline, the resulting waves evolve from unnoticeable to devastating, reaching heights of tens of meters and causing destruction of property and loss of life. Over 225,000 people were killed in the 2004 Indian Ocean tsunami alone. For many decades, scientists have been studying tsunami, and progress has been widely reported in connection with the causes (1), forecasting (2), and recovery (3). However, none of the studies ratifies the approach of a direct mitigation of tsunamis, with the exception of mitigation using submarine barriers (e.g. see Ref. (4)). In an attempt to open a discussion on direct mitigation, I examine the feasibility of redistributing the total energy of a very long surface ocean (gravity) wave over a larger space through nonlinear resonant interaction with two finely tuned acoustic-gravity waves (see Refs. (5-8)). Theoretically, while the energy input in the acoustic-gravity waves required for an effective interaction is comparable to that in a tsunami (i.e. impractically large), employing the proposed mitigation technique the initial tsunami amplitude could be reduced substantially resulting in a much milder impact at the coastline. Moreover, such a technique would allow for the harnessing of the tsunami's own energy. Practically, this mitigation technique requires the design of highly accurate acoustic-gravity wave frequency transmitters or modulators, which is a rather challenging ongoing engineering problem. References 1. E. Bryant, 2014. Tsunami: the underrated hazard. Springer, doi:10.1007/978-3-319- 06133-7. 2. V. V. Titov, F. I. Gonza`lez, E. N. Bernard, M. C. Eble, H. O. Mofjeld, J. C. Newman, A. J. Venturato, 2005. Real-Time Tsunami Forecasting: Challenges and Solutions. Nat. Hazards 35:41-58, doi:10

  20. On the potential for alternative greenhouse gas equivalence metrics to influence sectoral mitigation patterns

    NASA Astrophysics Data System (ADS)

    Brennan, Mark E.; Zaitchik, Benjamin F.

    2013-03-01

    Equivalence metrics used to quantify the relative climate impacts of different atmospheric forcers serve an essential function in policy and economic discussions about global climate change. The 100-year global warming potential (GWP-100), the most established greenhouse gas (GHG) equivalence metric, is used within the Kyoto Protocol, and in most emissions inventory, trading and offset mechanisms, to assign the mitigation value of non-carbon dioxide greenhouse gases relative to carbon dioxide. In recent literature the GWP-100 and alternative metrics have been used to compare various anthropogenic climate forcers with respect to a wide range of environmental and economic goals. Building on this work, we examine how 16 different static and time-varying CO2-equivalence schemes might influence GHG mitigation across sectors and gases in a perfect and fluid global mitigation regime. This mitigation regime is guided by achieving a global mean radiative forcing (RF) of 5.7 Wm-2 in 2100 from 1765 levels through a mitigation policy of prescribed emissions reductions in each decade. It was found that static metrics defined on 20- instead of 100-year time horizons favor mitigation strategies that maximize the abatement of short-lived gases (e.g. methane), on average resulting in an RF from methane in 2100 of 0.5 Wm-2 instead of 1.1 Wm-2 from 100-year metrics. Similarly, metrics that consider integrated rather than end-point climate impacts imply mitigation strategies that maximize mitigation of shorter-lived GHGs, resulting in higher abatement of agriculture and waste emissions. Comparing extreme scenarios, these mitigation shifts across gases and sectors result in a nearly 30% difference in the representation of methane in global cumulative emissions reductions. This shift across gases and sectors to mitigate shorter-lived GHGs, in lieu of longer-lived GHGs like carbon dioxide, has implications for the long-term warming commitment due to 21st century emissions.

  1. Engineering Polymer Blends for Impact Damage Mitigation

    NASA Technical Reports Server (NTRS)

    Gordon, Keith L.; Smith, Russell W.; Working, Dennis C.; Siochi, Emilie J.

    2016-01-01

    Structures containing polymers such as DuPont's Surlyn® 8940, demonstrate puncture healing when impacted by a 9 millimeter projectile traveling from speeds near 300 meters per second (1,100 feet per second) to hypervelocity impacts in the micrometeoroid velocity range of 5 kilometers per second (16,000 feet per second). Surlyn® 8940 puncture heals over a temperature range of minus 30 degrees Centigrade to plus 70 degrees Centigrade and shows potential for use in pressurized vessels subject to impact damage. However, such polymers are difficult to process and limited in applicability due to their low thermal stability, poor chemical resistance and overall poor mechanical properties. In this work, several puncture healing engineered melt formulations were developed. Moldings of melt blend formulations were impacted with a 5.56 millimeter projectile with a nominal velocity of 945 meters per second (3,100 feet per second) at about 25 degrees Centigrade, 50 degrees Centigrade and 100 degrees Centigrade, depending upon the specific blend being investigated. Self-healing tendencies were determined using surface vacuum pressure tests and tensile tests after penetration using tensile dog-bone specimens (ASTM D 638-10). For the characterization of tensile properties both pristine and impacted specimens were tested to obtain tensile modulus, yield stress and tensile strength, where possible. Experimental results demonstrate a range of new puncture healing blends which mitigate damage in the ballistic velocity regime.

  2. Resistive Exercise Device

    NASA Technical Reports Server (NTRS)

    Smith, Damon C. (Inventor)

    2005-01-01

    An exercise device 10 is particularly well suited for use in low gravity environments, and includes a frame 12 with plurality of resistance elements 30,82 supported in parallel on the frame. A load transfer member 20 is moveable relative to the frame for transferring the applied force to the free end of each captured resistance element. Load selection template 14 is removably secured both to the load transfer member, and a plurality of capture mechanisms engage the free end of corresponding resistance elements. The force applying mechanism 53 may be a handle, harness or other user interface for applying a force to move the load transfer member.

  3. Annual report on contractor work force restructuring, fiscal year 1997

    SciTech Connect

    1998-03-01

    This report summarizes work force restructuring and community transition activities at all sites. It outlines work force restructuring activity for FY 1997, changing separation patterns, cost savings and separation costs, program assessment, activities to mitigate restructuring impacts, community transition activities, status of displaced workers, lessons learned, and emerging issues in worker and community transition. Work force restructuring and community transition activities for defense nuclear sites are summarized, as are work force restructuring activities at non-defense sites.

  4. Improved attribution of climate forcing to emissions.

    PubMed

    Shindell, Drew T; Faluvegi, Greg; Koch, Dorothy M; Schmidt, Gavin A; Unger, Nadine; Bauer, Susanne E

    2009-10-30

    Evaluating multicomponent climate change mitigation strategies requires knowledge of the diverse direct and indirect effects of emissions. Methane, ozone, and aerosols are linked through atmospheric chemistry so that emissions of a single pollutant can affect several species. We calculated atmospheric composition changes, historical radiative forcing, and forcing per unit of emission due to aerosol and tropospheric ozone precursor emissions in a coupled composition-climate model. We found that gas-aerosol interactions substantially alter the relative importance of the various emissions. In particular, methane emissions have a larger impact than that used in current carbon-trading schemes or in the Kyoto Protocol. Thus, assessments of multigas mitigation policies, as well as any separate efforts to mitigate warming from short-lived pollutants, should include gas-aerosol interactions.

  5. Mitigation of inflammation with foods.

    PubMed

    Wu, Xianli; Schauss, Alexander G

    2012-07-11

    Constant overproduction of pro-inflammatory molecules leads to chronic inflammation. Unlike acute inflammation, which is essential for healing, chronic inflammation can delay healing and, if left unchecked, contribute to a host of diseases. There is growing evidence that some dietary factors can play important roles in maintaining health and even reversing the progression of chronic diseases, with anti-inflammatory effects as important underlying mechanism. Such findings add to the body of evidence that certain dietary components, including polyphenols and other types of compounds, found in various dietary factors including fruits, berries, vegetables, nuts, whole grains, and foods of marine origin, can play an important role in attenuating and mitigating chronic pro-inflammatory processes associated with chronic diseases.

  6. Acoustic metamaterials for sound mitigation

    NASA Astrophysics Data System (ADS)

    Assouar, Badreddine; Oudich, Mourad; Zhou, Xiaoming

    2016-05-01

    We provide theoretical and numerical analyses of the behavior of a plate-type acoustic metamaterial considered in an air-borne sound environment in view of sound mitigation application. Two configurations of plate are studied, a spring-mass one and a pillar system-based one. The acoustic performances of the considered systems are investigated with different approaches and show that a high sound transmission loss (STL) up to 82 dB is reached with a metamaterial plate with a thickness of 0.5 mm. The physical understanding of the acoustic behavior of the metamaterial partition is discussed based on both air-borne and structure-borne approaches. Confrontation between the STL, the band structure, the displacement fields and the effective mass density of the plate metamaterial is made to have a complete physical understanding of the different mechanisms involved.

  7. Mitigating Resistance to Teaching Science through Inquiry: Studying Self

    ERIC Educational Resources Information Center

    Spector, Barbara; Burkett, Ruth S.; Leard, Cyndy

    2007-01-01

    This is the report of a qualitative emergent-design study of 2 different Web-enhanced science methods courses for preservice elementary teachers in which an experiential learning strategy, labeled "using yourself as a learning laboratory," was implemented. Emergent grounded theory indicated this strategy, when embedded in a course organized as an…

  8. Birefringence and residual stress induced by CO2 laser mitigation of damage growth in fused silica

    NASA Astrophysics Data System (ADS)

    Gallais, L.; Cormont, P.; Rullier, J. L.

    2009-10-01

    We investigate the residual stress field created near mitigated sites and its influence on the efficiency on the CO2 laser mitigation of damage growth process. A numerical model of CO2 laser interaction with fused silica is developed that take into account laser energy absorption, heat transfer, thermally-induced stress and birefringence. Specific photoelastic methods are developed to characterize the residual stress near mitigated sites in fused silica samples. The stress distribution and quantitative values of stress levels are obtained for sites treated with the CO2 laser in various conditions of energy deposition (beam size, pulse duration, incident power). The results obtained also show that the presence of birefringence/residual stress around the mitigated sites has a critical effect on their laser damage resistance.

  9. Labor Force

    ERIC Educational Resources Information Center

    Occupational Outlook Quarterly, 2010

    2010-01-01

    The labor force is the number of people aged 16 or older who are either working or looking for work. It does not include active-duty military personnel or institutionalized people, such as prison inmates. Quantifying this total supply of labor is a way of determining how big the economy can get. Labor force participation rates vary significantly…

  10. The Common Forces: Conservative or Nonconservative?

    ERIC Educational Resources Information Center

    Keeports, David

    2006-01-01

    Of the forces commonly encountered when solving problems in Newtonian mechanics, introductory texts usually limit illustrations of the definitions of conservative and nonconservative forces to gravity, spring forces, kinetic friction and fluid resistance. However, at the expense of very little class time, the question of whether each of the common…

  11. The Common Forces: Conservative or Nonconservative?

    ERIC Educational Resources Information Center

    Keeports, David

    2006-01-01

    Of the forces commonly encountered when solving problems in Newtonian mechanics, introductory texts usually limit illustrations of the definitions of conservative and nonconservative forces to gravity, spring forces, kinetic friction and fluid resistance. However, at the expense of very little class time, the question of whether each of the common…

  12. Assessment of the multimedia mitigation of radon in New York.

    PubMed

    Kitto, Michael E

    2007-05-01

    Although not yet implemented, the 1996 amendments to the Safe Drinking Water Act instructed the states (or local water suppliers) to address radon concentrations in community water systems (CWS). As an alternative to reducing waterborne radon concentrations in the CWS to the maximum contaminant level (MCL) of 11 Bq L(-1), states (or individual CWS) would be permitted to develop a multimedia mitigation (MMM) program, which allowed a greater concentration (148 Bq L(-1)) of waterborne radon in the CWS, if it could be shown that an equivalent health risk reduction could be achieved by reducing indoor radon concentrations. For a MMM program to be acceptable, the U.S. Environmental Protection Agency required the health-risk reduction attained through mitigations and radon-resistant new construction (RRNC) to offset the increased health risk due to radon in community water systems above the MCL of 11 Bq L(-1). A quantitative assessment indicates that the reduction in health risk currently achieved in New York State through radon mitigations and RRNC exceeded the increase in risk associated with an alternative MCL of 148 Bq L(-1). The implementation of a MMM program in New York would result in an overall reduction in the health risk associated with exposure to radon.

  13. Advanced Mitigation Process (AMP) for Improving Laser Damage Threshold of Fused Silica Optics

    PubMed Central

    Ye, Xin; Huang, Jin; Liu, Hongjie; Geng, Feng; Sun, Laixi; Jiang, Xiaodong; Wu, Weidong; Qiao, Liang; Zu, Xiaotao; Zheng, Wanguo

    2016-01-01

    The laser damage precursors in subsurface of fused silica (e.g. photosensitive impurities, scratches and redeposited silica compounds) were mitigated by mineral acid leaching and HF etching with multi-frequency ultrasonic agitation, respectively. The comparison of scratches morphology after static etching and high-frequency ultrasonic agitation etching was devoted in our case. And comparison of laser induce damage resistance of scratched and non-scratched fused silica surfaces after HF etching with high-frequency ultrasonic agitation were also investigated in this study. The global laser induce damage resistance was increased significantly after the laser damage precursors were mitigated in this case. The redeposition of reaction produce was avoided by involving multi-frequency ultrasonic and chemical leaching process. These methods made the increase of laser damage threshold more stable. In addition, there is no scratch related damage initiations found on the samples which were treated by Advanced Mitigation Process. PMID:27484188

  14. Advanced Mitigation Process (AMP) for Improving Laser Damage Threshold of Fused Silica Optics.

    PubMed

    Ye, Xin; Huang, Jin; Liu, Hongjie; Geng, Feng; Sun, Laixi; Jiang, Xiaodong; Wu, Weidong; Qiao, Liang; Zu, Xiaotao; Zheng, Wanguo

    2016-08-03

    The laser damage precursors in subsurface of fused silica (e.g. photosensitive impurities, scratches and redeposited silica compounds) were mitigated by mineral acid leaching and HF etching with multi-frequency ultrasonic agitation, respectively. The comparison of scratches morphology after static etching and high-frequency ultrasonic agitation etching was devoted in our case. And comparison of laser induce damage resistance of scratched and non-scratched fused silica surfaces after HF etching with high-frequency ultrasonic agitation were also investigated in this study. The global laser induce damage resistance was increased significantly after the laser damage precursors were mitigated in this case. The redeposition of reaction produce was avoided by involving multi-frequency ultrasonic and chemical leaching process. These methods made the increase of laser damage threshold more stable. In addition, there is no scratch related damage initiations found on the samples which were treated by Advanced Mitigation Process.

  15. Advanced Mitigation Process (AMP) for Improving Laser Damage Threshold of Fused Silica Optics

    NASA Astrophysics Data System (ADS)

    Ye, Xin; Huang, Jin; Liu, Hongjie; Geng, Feng; Sun, Laixi; Jiang, Xiaodong; Wu, Weidong; Qiao, Liang; Zu, Xiaotao; Zheng, Wanguo

    2016-08-01

    The laser damage precursors in subsurface of fused silica (e.g. photosensitive impurities, scratches and redeposited silica compounds) were mitigated by mineral acid leaching and HF etching with multi-frequency ultrasonic agitation, respectively. The comparison of scratches morphology after static etching and high-frequency ultrasonic agitation etching was devoted in our case. And comparison of laser induce damage resistance of scratched and non-scratched fused silica surfaces after HF etching with high-frequency ultrasonic agitation were also investigated in this study. The global laser induce damage resistance was increased significantly after the laser damage precursors were mitigated in this case. The redeposition of reaction produce was avoided by involving multi-frequency ultrasonic and chemical leaching process. These methods made the increase of laser damage threshold more stable. In addition, there is no scratch related damage initiations found on the samples which were treated by Advanced Mitigation Process.

  16. Enhancing the Global Carbon Sink: A Key Mitigation Strategy

    NASA Astrophysics Data System (ADS)

    Torn, M. S.

    2016-12-01

    Earth's terrestrial ecosystems absorb about one-third of all anthropogenic CO2 emissions from the atmosphere each year, greatly reducing the climate forcing those emissions would otherwise cause. This puts the size of the terrestrial carbon sink on par with the most aggressive climate mitigation measures proposed. Moreover, the land sink has been keeping pace with rising emissions and has roughly doubled over the past 40 years. But there is a fundamental lack of understanding of why the sink has been increasing and what its future trajectory could be. In developing climate mitigation strategies, governments have a very limited scientific basis for projecting the contributions of their domestic sinks, and yet at least 117 of the 160 COP21 signatories stated they will use the land sink in their Nationally Defined Contribution (NDC). Given its potentially critical role in reducing net emissions and the importance of UNFCCC land sinks in future mitigation scenarios, a first-principles understanding of the dynamics of the land sink is needed. For expansion of the sink, new approaches and ecologically-sound technologies are needed. Carefully conceived terrestrial carbon sequestration could have multiple environmental benefits, but a massive expansion of land carbon sinks using conventional approaches could place excessive demands on the world's land, water, and fertilizer nutrients. Meanwhile, rapid climatic change threatens to undermine or reverse the sink in many ecosystems. We need approaches to protect the large sinks that are currently assumed useful for climate mitigation. Thus we highlight the need for a new research agenda aimed at predicting, protecting, and enhancing the global carbon sink. Key aspects of this agenda include building a predictive capability founded on observations, theory and models, and developing ecological approaches and technologies that are sustainable and scalable, and potentially provide co-benefits such as healthier soils, more

  17. Economic outcomes of greenhouse gas mitigation options

    USDA-ARS?s Scientific Manuscript database

    Economic outcomes of greenhouse gas (GHG) mitigation options are reviewed including reductions in tillage intensity, diversifying crop rotation, and N fertilizer management. The review indicates that, while reducing tillage can be a cost effective GHG mitigation practice, results vary by region and ...

  18. Wake Turbulence Mitigation for Arrivals (WTMA)

    NASA Technical Reports Server (NTRS)

    Williams, Daniel M.; Lohr, Gary W.; Trujillo, Anna C.

    2008-01-01

    The preliminary Wake Turbulence Mitigation for Arrivals (WTMA) concept of operations is described in this paper. The WTMA concept provides further detail to work initiated by the Wake Vortex Avoidance System Concept Evaluation Team and is an evolution of the Wake Turbulence Mitigation for Departure concept. Anticipated benefits about reducing wake turbulence separation standards in crosswind conditions, and candidate WTMA system considerations are discussed.

  19. 40 CFR 1508.20 - Mitigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Mitigation. 1508.20 Section 1508.20 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.20 Mitigation... eliminating the impact over time by preservation and maintenance operations during the life of the action. (e...

  20. 40 CFR 1508.20 - Mitigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Mitigation. 1508.20 Section 1508.20 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.20 Mitigation... eliminating the impact over time by preservation and maintenance operations during the life of the action. (e...

  1. 40 CFR 1508.20 - Mitigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Mitigation. 1508.20 Section 1508.20 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.20 Mitigation... eliminating the impact over time by preservation and maintenance operations during the life of the action. (e...

  2. 40 CFR 1508.20 - Mitigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Mitigation. 1508.20 Section 1508.20 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.20 Mitigation... eliminating the impact over time by preservation and maintenance operations during the life of the action. (e...

  3. Hurricane risk mitigation - High Pressure Gas Facility

    NASA Technical Reports Server (NTRS)

    2008-01-01

    A worker pours concrete as part of a nitrogen risk mitigation project at the High Pressure Gas Facility at Stennis Space Center. The concrete slab will provide the foundation needed to place new pumps at the site and is part of ongoing hurricane-related mitigation work at Stennis.

  4. Mitigation assessment results and priorities in China

    SciTech Connect

    Wu Zongxin; Wei Zhihong

    1996-12-31

    In this paper energy related CO2 emission projections of China by 2030 are given. CO2 mitigation potential and technology options in main fields of energy conservation and energy substitution are analyzed. CO2 reduction costs of main mitigation technologies are estimated and the AHP approach is used for helping assessment of priority technologies.

  5. Hurricane risk mitigation - High Pressure Gas Facility

    NASA Image and Video Library

    2008-07-29

    A worker pours concrete as part of a nitrogen risk mitigation project at the High Pressure Gas Facility at Stennis Space Center. The concrete slab will provide the foundation needed to place new pumps at the site and is part of ongoing hurricane-related mitigation work at Stennis.

  6. [Rodenticide resistance and consequences].

    PubMed

    Esther, A; Endepols, S; Freise, J; Klemann, N; Runge, M; Pelz, H-J

    2014-05-01

    Resistance to anticoagulant rodenticides, such as warfarin was first described in 1958. Polymorphisms in the vitamin K epoxide reductase complex subunit 1 (VKORC1) gene and respective substitutions of amino acids in the VKOR enzyme are the major cause for rodenticide resistance. Resistant Norway rats in Germany are characterized by the Tyr139Cys genotype, which is spread throughout the northwest of the country. Resistant house mice with the VKOR variants Tyr139Cys, Leu128Ser and Arg12Trp/Ala26Ser/Ala48Thr/Arg61Leu (spretus type) are distributed over a number of locations in Germany. Resistance can reduce management attempts with consequences for stored product protection, hygiene and animal health. Anticoagulants of the first generation (warfarin, chlorophacinone, coumatetralyl) as well as bromadiolone and difenacoum are not an option for the control of resistant Norway rats. The same applies for house mice whereby the tolerance to compounds can be different between local incidences. Due to the higher toxicity and tendency to persist, the most potent anticoagulant rodenticides brodifacoum, flocoumafen and difethialone should be applied but only where resistance is known. In other cases less toxic anticoagulants should be preferred for rodent management in order to mitigate environmental risks. Resistance effects of further VKOR polymorphisms and their combinations, the spread of resistant rats and conditions supporting and reducing resistance should be investigated in order to improve resistance management strategies.

  7. Force sensor

    DOEpatents

    Grahn, Allen R.

    1993-01-01

    A force sensor and related method for determining force components. The force sensor includes a deformable medium having a contact surface against which a force can be applied, a signal generator for generating signals that travel through the deformable medium to the contact surface, a signal receptor for receiving the signal reflected from the contact surface, a generation controller, a reception controller, and a force determination apparatus. The signal generator has one or more signal generation regions for generating the signals. The generation controller selects and activates the signal generation regions. The signal receptor has one or more signal reception regions for receiving signals and for generating detections signals in response thereto. The reception controller selects signal reception regions and detects the detection signals. The force determination apparatus measures signal transit time by timing activation and detection and, optionally, determines force components for selected cross-field intersections. The timer which times by activation and detection can be any means for measuring signal transit time. A cross-field intersection is defined by the overlap of a signal generation region and a signal reception region.

  8. Force sensor

    DOEpatents

    Grahn, A.R.

    1993-05-11

    A force sensor and related method for determining force components is described. The force sensor includes a deformable medium having a contact surface against which a force can be applied, a signal generator for generating signals that travel through the deformable medium to the contact surface, a signal receptor for receiving the signal reflected from the contact surface, a generation controller, a reception controller, and a force determination apparatus. The signal generator has one or more signal generation regions for generating the signals. The generation controller selects and activates the signal generation regions. The signal receptor has one or more signal reception regions for receiving signals and for generating detections signals in response thereto. The reception controller selects signal reception regions and detects the detection signals. The force determination apparatus measures signal transit time by timing activation and detection and, optionally, determines force components for selected cross-field intersections. The timer which times by activation and detection can be any means for measuring signal transit time. A cross-field intersection is defined by the overlap of a signal generation region and a signal reception region.

  9. Flow-force relationships in lettuce thylakoids. 2. Effect of the uncoupler FCCP on local proton resistances at the ATPase level.

    PubMed

    Sigalat, C; de Kouchkovsky, Y; Haraux, F

    1993-09-28

    The relationship between the steady-state proton gradient (delta pH) and the rate of phosphorylation was investigated in thylakoids under various conditions. Under partial uncoupling by carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone (FCCP), the rate of ATP synthesis was reduced by less than expected from the decrease of delta pH. This was observed in the case of the pyocyanine-mediated cyclic electron flow around photosystem 1, but not with the H2O-->photosystem 2-->cytochrome b6f-->photosystem 1-->methyl viologen system. In state 4, a unique relation was found between delta pH and the "phosphate potential", delta Gp, regardless of whether the energy level was controlled by light input or FCCP. The anomalous effect of FCCP on the rate of ATP synthesis disappeared when the ATPase was partially blocked by the reversible inhibitor venturicidin, but not in the presence of tentoxin, an irreversible inhibitor. These results are consistent with the existence of a small kinetic barrier for protons, limiting their access to the ATPase. This resistance would be collapsed by FCCP.

  10. Long term performance of radon mitigation systems

    SciTech Connect

    Prill, R.; Fisk, W.J.

    2002-03-01

    Researchers installed radon mitigation systems in 12 houses in Spokane, Washington and Coeur d'Alene, Idaho during the heating season 1985--1986 and continued to monitor indoor radon quarterly and annually for ten years. The mitigation systems included active sub-slab ventilation, basement over-pressurization, and crawlspace isolation and ventilation. The occupants reported various operational problems with these early mitigation systems. The long-term radon measurements were essential to track the effectiveness of the mitigation systems over time. All 12 homes were visited during the second year of the study, while a second set 5 homes was visited during the fifth year to determine the cause(s) of increased radon in the homes. During these visits, the mitigation systems were inspected and measurements of system performance were made. Maintenance and modifications were performed to improve system performance in these homes.

  11. Structural master plan of flood mitigation measures

    NASA Astrophysics Data System (ADS)

    Heidari, A.

    2009-01-01

    Flood protection is one of the practical methods in damage reduction. Although it not possible to be completely protected from flood disaster but major part of damages can be reduced by mitigation plans. In this paper, the optimum flood mitigation master plan is determined by economic evaluation in trading off between the construction costs and expected value of damage reduction as the benefits. Size of the certain mitigation alternative is also be obtained by risk analysis by accepting possibility of flood overtopping. Different flood mitigation alternatives are investigated from various aspects in the Dez and Karun river floodplain areas as a case study in south west of IRAN. The results show that detention dam and flood diversion are the best alternatives of flood mitigation methods as well as enforcing the flood control purpose of upstream multipurpose reservoirs. Dyke and levees are not mostly justifiable because of negative impact on down stream by enhancing routed flood peak discharge magnitude and flood damages as well.

  12. A public health hazard mitigation planning process.

    PubMed

    Griffith, Jennifer M; Kay Carpender, S; Crouch, Jill Artzberger; Quiram, Barbara J

    2014-01-01

    The Texas A&M Health Science Center School of Rural Public Health, a member of the Training and Education Collaborative System Preparedness and Emergency Response Learning Center (TECS-PERLC), has long-standing partnerships with 2 Health Service Regions (Regions) in Texas. TECS-PERLC was contracted by these Regions to address 2 challenges identified in meeting requirements outlined by the Risk-Based Funding Project. First, within Metropolitan Statistical Areas, there is not a formal authoritative structure. Second, preexisting tools and processes did not adequately satisfy requirements to assess public health, medical, and mental health needs and link mitigation strategies to the Public Health Preparedness Capabilities, which provide guidance to prepare for, respond to, and recover from public health incidents. TECS-PERLC, with its partners, developed a framework to interpret and apply results from the Texas Public Health Risk Assessment Tool (TxPHRAT). The 3-phase community engagement-based TxPHRAT Mitigation Planning Process (Mitigation Planning Process) and associated tools facilitated the development of mitigation plans. Tools included (1) profiles interpreting TxPHRAT results and identifying, ranking, and prioritizing hazards and capability gaps; (2) a catalog of intervention strategies and activities linked to hazards and capabilities; and (3) a template to plan, evaluate, and report mitigation planning efforts. The Mitigation Planning Process provided a framework for Regions to successfully address all funding requirements. TECS-PERLC developed more than 60 profiles, cataloged and linked 195 intervention strategies, and developed a template resulting in 20 submitted mitigation plans. A public health-focused, community engagement-based mitigation planning process was developed by TECS-PERLC and successfully implemented by the Regions. The outcomes met all requirements and reinforce the effectiveness of academic practice partnerships and importance of

  13. Assessing the Climatic Benefits of Black Carbon Mitigation

    NASA Astrophysics Data System (ADS)

    Mauzerall, D. L.; Kopp, R. E.

    2010-12-01

    To limit mean global warming to 2 °C, a goal supported by more than 100 countries, it will likely be necessary to reduce emissions not only of greenhouse gases but also of air pollutants with high radiative forcing (RF), particularly black carbon (BC). Although several recent research papers have attempted to quantify the effects of BC on climate, not all these analyses have incorporated all the mechanisms that contribute to its RF (including the effects of BC on cloud albedo, cloud coverage, and snow and ice albedo, and the optical consequences of aerosol mixing) and have reported their results in different units and with different ranges of uncertainty. Here we attempt to reconcile their results and present them in uniform units that include the same forcing factors. We use the best estimate of effective RF obtained from these results to analyze the benefits of mitigating BC emissions for achieving a specific equilibrium temperature target. For a 500 ppm CO2e (3.1 Wm-2) effective RF target in 2100, which would offer about a 50% chance of limiting equilibrium warming to 2.5 °C above preindustrial temperatures, we estimate that failing to reduce carbonaceous aerosol emissions from contained combustion would require CO2 emission cuts about 8 years (range of 1-15 years) earlier than would be necessary with full mitigation of these emissions.

  14. Assessing the climatic benefits of black carbon mitigation

    PubMed Central

    Kopp, Robert E.; Mauzerall, Denise L.

    2010-01-01

    To limit mean global warming to 2 °C, a goal supported by more than 100 countries, it will likely be necessary to reduce emissions not only of greenhouse gases but also of air pollutants with high radiative forcing (RF), particularly black carbon (BC). Although several recent research papers have attempted to quantify the effects of BC on climate, not all these analyses have incorporated all the mechanisms that contribute to its RF (including the effects of BC on cloud albedo, cloud coverage, and snow and ice albedo, and the optical consequences of aerosol mixing) and have reported their results in different units and with different ranges of uncertainty. Here we attempt to reconcile their results and present them in uniform units that include the same forcing factors. We use the best estimate of effective RF obtained from these results to analyze the benefits of mitigating BC emissions for achieving a specific equilibrium temperature target. For a 500 ppm CO2e (3.1 W m-2) effective RF target in 2100, which would offer about a 50% chance of limiting equilibrium warming to 2.5 °C above preindustrial temperatures, we estimate that failing to reduce carbonaceous aerosol emissions from contained combustion would require CO2 emission cuts about 8 years (range of 1–15 years) earlier than would be necessary with full mitigation of these emissions. PMID:20566891

  15. Assessing the climatic benefits of black carbon mitigation.

    PubMed

    Kopp, Robert E; Mauzerall, Denise L

    2010-06-29

    To limit mean global warming to 2 degrees C, a goal supported by more than 100 countries, it will likely be necessary to reduce emissions not only of greenhouse gases but also of air pollutants with high radiative forcing (RF), particularly black carbon (BC). Although several recent research papers have attempted to quantify the effects of BC on climate, not all these analyses have incorporated all the mechanisms that contribute to its RF (including the effects of BC on cloud albedo, cloud coverage, and snow and ice albedo, and the optical consequences of aerosol mixing) and have reported their results in different units and with different ranges of uncertainty. Here we attempt to reconcile their results and present them in uniform units that include the same forcing factors. We use the best estimate of effective RF obtained from these results to analyze the benefits of mitigating BC emissions for achieving a specific equilibrium temperature target. For a 500 ppm CO(2)e (3.1 W m(-2)) effective RF target in 2100, which would offer about a 50% chance of limiting equilibrium warming to 2.5 degrees C above preindustrial temperatures, we estimate that failing to reduce carbonaceous aerosol emissions from contained combustion would require CO(2) emission cuts about 8 years (range of 1-15 years) earlier than would be necessary with full mitigation of these emissions.

  16. 44 CFR 78.5 - Flood Mitigation Plan development.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Flood Mitigation Plan..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program FLOOD MITIGATION ASSISTANCE § 78.5 Flood Mitigation Plan development. A Flood Mitigation Plan will articulate a...

  17. 44 CFR 78.5 - Flood Mitigation Plan development.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 44 Emergency Management and Assistance 1 2012-10-01 2011-10-01 true Flood Mitigation Plan..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program FLOOD MITIGATION ASSISTANCE § 78.5 Flood Mitigation Plan development. A Flood Mitigation Plan will articulate a...

  18. Using FRET for Drought Mitigation

    NASA Astrophysics Data System (ADS)

    Osborne, H. D.; Palmer, C. K.; Hobbins, M.

    2016-12-01

    With the ongoing drought plaguing California and much of the Western United States, water agencies and the general public have a heightened need for short term forecasts of evapotranspiration. The National Weather Service's (NWS) Forecast Reference Evapotranspiration (FRET) product suite can fill this need. The FRET product suite uses the Penman - Monteith Reference Evapotranspiration (ETrc) equation for a short canopy (12 cm grasses), adopted by the Environmental Water Resources Institute of the American Society of Civil Engineers. FRET is calculated across the contiguous U.S. using temperatures, humidity, winds, and sky cover from Numerical Weather Prediction (NPW) models and adjusted by NWS forecasters with local expertise of terrain and weather patterns. The Weekly ETrc product is easily incorporated into drought-planning strategies, allowing water managers, the agricultural community, and the public to make better informed water-use decisions. FRET can assist with the decision making process for scheduling irrigation (e.g., farms, golf courses, vineyards) and timing of fertilizers. The California Department of Water Resources (CA DWR) also ingests the FRET into their soil moisture models, and uses FRET to assist in determining the reservoir releases for the Feather River. The United States Bureau of Reclamation (USBR) also uses FRET in determining reservoir releases and assessing water temperature along the Sacramento and American Rivers. FRET is now operational on the National Digital Forecast Database (NDFD), permitting other agencies easy access to this nationwide data for all drought mitigation and planning purposes.

  19. Mitigation of Fluorosis - A Review.

    PubMed

    Khairnar, Mahesh R; Dodamani, Arun S; Jadhav, Harish C; Naik, Rahul G; Deshmukh, Manjiri A

    2015-06-01

    Fluoride is required for normal development and growth of the body. It is found in plentiful quantity in environment and fluoride content in drinking water is largest contributor to the daily fluoride intake. The behaviour of fluoride ions in the human organism can be regarded as that of "double-edged sword". Fluoride is beneficial in small amounts but toxic in large amounts. Excessive consumption of fluorides in various forms leads to development of fluorosis. Fluorosis is major health problem in 24 countries, including India, which lies in the geographical fluoride belt. Various technologies are being used to remove fluoride from water but still the problem has not been rooted out. The purpose of this paper is to review the available treatment modalities for fluorosis, available technologies for fluoride removal from water and ongoing fluorosis mitigation programs based on literature survey. Medline was the primary database used in the literature search. Other databases included: PubMed, Web of Science, Google Scholar, WHO, Ebscohost, Science Direct, Google Search Engine, etc.

  20. Inhaling to mitigate exhaled bioaerosols

    PubMed Central

    Edwards, David A.; Man, Jonathan C.; Brand, Peter; Katstra, Jeffrey P.; Sommerer, K.; Stone, Howard A.; Nardell, Edward; Scheuch, Gerhard

    2004-01-01

    Humans commonly exhale aerosols comprised of small droplets of airway-lining fluid during normal breathing. These “exhaled bioaerosols” may carry airborne pathogens and thereby magnify the spread of certain infectious diseases, such as influenza, tuberculosis, and severe acute respiratory syndrome. We hypothesize that, by altering lung airway surface properties through an inhaled nontoxic aerosol, we might substantially diminish the number of exhaled bioaerosol droplets and thereby provide a simple means to potentially mitigate the spread of airborne infectious disease independently of the identity of the airborne pathogen or the nature of any specific therapy. We find that some normal human subjects expire many more bioaerosol particles than other individuals during quiet breathing and therefore bear the burden of production of exhaled bioaerosols. Administering nebulized isotonic saline to these “high-producer” individuals diminishes the number of exhaled bioaerosol particles expired by 72.10 ± 8.19% for up to 6 h. In vitro and in vivo experiments with saline and surfactants suggest that the mechanism of action of the nebulized saline relates to modification of the physical properties of the airway-lining fluid, notably surface tension. PMID:15583121

  1. Inhaling to mitigate exhaled bioaerosols.

    PubMed

    Edwards, David A; Man, Jonathan C; Brand, Peter; Katstra, Jeffrey P; Sommerer, K; Stone, Howard A; Nardell, Edward; Scheuch, Gerhard

    2004-12-14

    Humans commonly exhale aerosols comprised of small droplets of airway-lining fluid during normal breathing. These "exhaled bioaerosols" may carry airborne pathogens and thereby magnify the spread of certain infectious diseases, such as influenza, tuberculosis, and severe acute respiratory syndrome. We hypothesize that, by altering lung airway surface properties through an inhaled nontoxic aerosol, we might substantially diminish the number of exhaled bioaerosol droplets and thereby provide a simple means to potentially mitigate the spread of airborne infectious disease independently of the identity of the airborne pathogen or the nature of any specific therapy. We find that some normal human subjects expire many more bioaerosol particles than other individuals during quiet breathing and therefore bear the burden of production of exhaled bioaerosols. Administering nebulized isotonic saline to these "high-producer" individuals diminishes the number of exhaled bioaerosol particles expired by 72.10 +/- 8.19% for up to 6 h. In vitro and in vivo experiments with saline and surfactants suggest that the mechanism of action of the nebulized saline relates to modification of the physical properties of the airway-lining fluid, notably surface tension.

  2. Mitigation of Fluorosis - A Review

    PubMed Central

    Dodamani, Arun S.; Jadhav, Harish C.; Naik, Rahul G.; Deshmukh, Manjiri A.

    2015-01-01

    Fluoride is required for normal development and growth of the body. It is found in plentiful quantity in environment and fluoride content in drinking water is largest contributor to the daily fluoride intake. The behaviour of fluoride ions in the human organism can be regarded as that of “double-edged sword”. Fluoride is beneficial in small amounts but toxic in large amounts. Excessive consumption of fluorides in various forms leads to development of fluorosis. Fluorosis is major health problem in 24 countries, including India, which lies in the geographical fluoride belt. Various technologies are being used to remove fluoride from water but still the problem has not been rooted out. The purpose of this paper is to review the available treatment modalities for fluorosis, available technologies for fluoride removal from water and ongoing fluorosis mitigation programs based on literature survey. Medline was the primary database used in the literature search. Other databases included: PubMed, Web of Science, Google Scholar, WHO, Ebscohost, Science Direct, Google Search Engine, etc. PMID:26266235

  3. Gas Mitigation in Paper Production

    NASA Astrophysics Data System (ADS)

    Santos, AS; Bittencourt, C.

    2017-07-01

    The Brazilian paper industry has competitive advantages offered by the favorable climate, which favors an increase in the yield of forest restoration, and consequently, in the productive process. On the other hand, following the greenhouse gases (GHG), we can see our constantly changing sun, causing the solar storms, allowing their prevention or mitigating measures. The objective of this work is to contribute to the construction of the understanding necessary for the reduction of GHG emission from a preliminary analysis of the pulp and paper sector. As a secondary objective, the text preliminarily analyzes a company’s behavior against the backdrop of the Paris Accord, which strengthens the global response to the threat of climate change and strengthens the capacity of countries to deal with the impacts of such changes. The identification of best practices in the pulp and paper industry is understood, focusing on environmental sustainability, such as the adoption of reforestation, obtaining significant results. In the case of the paper industry, the management of public forests for sustainable production, within the structure of the Ministry of the Environment, establishes the promotion of public awareness about the importance of conservation, recovery and sustainable management of forest resources.

  4. Mitigation of Space Radiation Effects

    NASA Astrophysics Data System (ADS)

    Atwell, William

    2012-02-01

    During low earth orbit and deep space missions, humans and spacecraft systems are exposed to high energy particles emanating from basically three sources: geomagnetically-trapped protons and electrons (Van Allen Belts), extremely high energy galactic cosmic radiation (GCR), and solar proton events (SPEs). The particles can have deleterious effects if not properly shielded. For humans, there can be a multitude of harmful effects depending on the degree of exposure. For spacecraft systems, especially electronics, the effects can range from single event upsets (SEUs) to catastrophic effects such as latchup and burnout. In addition, some materials, radio-sensitive experiments, and scientific payloads are subject to harmful effects. To date, other methods have been proposed such as electrostatic and electromagnetic shielding, but these approaches have not proven feasible due to cost, weight, and safety issues. The only method that has merit and has been effective is bulk or parasitic shielding. In this paper, we discuss in detail the sources of the space radiation environment, spacecraft, human, and onboard systems modeling methodologies, transport of these particles through shielding materials, and the calculation of the dose effects. In addition, a review of the space missions to date and a discussion of the space radiation mitigation challenges for lunar and deep space missions such as lunar outposts and human missions to Mars are presented.

  5. Mitigation Approaches to Combat the Flu Pandemic

    PubMed Central

    Chawla, Raman; Sharma, Rakesh Kumar; Madaan, Deepali; Dubey, Neha; Arora, Rajesh; Goel, Rajeev; Singh, Shefali; Kaushik, Vinod; Singh, Pankaj Kumar; Chabbra, Vivek; Bhardwaj, Janak Raj

    2009-01-01

    Management of flu pandemic is a perpetual challenge for the medical fraternity since time immemorial. Animal to human transmission has been observed thrice in the last century within an average range of 11-39 years of antigenic recycling. The recent outbreak of influenza A (H1N1, also termed as swine flu), first reported in Mexico on April 26, 2009, occurred in the forty first year since last reported flu pandemic (July 1968). Within less than 50 days, it has assumed pandemic proportions (phase VI) affecting over 76 countries with 163 deaths/35,928 cases (as on 15th June 2009). It indicated the re-emergence of genetically reassorted virus having strains endemic to humans, swine and avian (H5N1). The World Health Organisation (WHO) member states have already pulled up their socks and geared up to combat such criticalities. Earlier outbreaks of avian flu (H5N1) in different countries led WHO to develop pandemic preparedness strategies with national/regional plans on pandemic preparedness. Numerous factors related to climatic conditions, socio-economic strata, governance and sharing of information/logistics at all levels have been considered critical indicators in monitoring the dynamics of escalation towards a pandemic situation. The National Disaster Management Authority (NDMA), Government of India, with the active cooperation of UN agencies and other stakeholders/experts has formulated a concept paper on role of nonhealth service providers during pandemics in April 2008 and released national guidelines - management of biological disasters in July 2008. These guidelines enumerate that the success of medical management endeavors like pharmaceutical (anti-viral Oseltamivir and Zanamivir therapies), nonpharmaceutical interventions and vaccination development etc., largely depends on level of resistance offered by mutagenic viral strain and rationale use of pharmaco therapeutic interventions. This article describes the mitigation approach to combat flu pandemic with its

  6. [French Society for Biological Psychiatry and Neuropsychopharmacology and Fondation FondaMental task force: Formal Consensus for the management of treatment-resistant depression].

    PubMed

    Charpeaud, T; Genty, J-B; Destouches, S; Yrondi, A; Lancrenon, S; Alaïli, N; Bellivier, F; Bennabi, D; Bougerol, T; Camus, V; D'amato, T; Doumy, O; Haesebaert, F; Holtzmann, J; Lançon, C; Lefebvre, M; Moliere, F; Nieto, I; Richieri, R; Schmitt, L; Stephan, F; Vaiva, G; Walter, M; Leboyer, M; El-Hage, W; Haffen, E; Llorca, P-M; Courtet, P; Aouizerate, B

    2017-09-01

    situations (clinical features, specific populations, psychiatric comorbidities, etc.). Thus, the present approach will be especially helpful for the clinicians enabling to substantially facilitate and guide their clinical decision when confronted to difficult-to-treat forms of major depression in the daily clinical practice. This will be expected to significantly improve the poor prognosis of the treatment-resistant depression thereby lowering the clinical, functional and costly impact owing directly to the disease. © 2017 L’Encéphale, Paris.

  7. Air Force Officer Evaluation System Project

    DTIC Science & Technology

    1987-01-01

    supervisor-subordinate relationships, and most private sector organizations ti"-n supervisors to give such feedback. AIR FORCE CULTURE o There exists...Alternative OER designs should reflect and sustain the larger Air Force culture ; 0 Within the Air Force, the alternative OER designs should encourage change...given the Air Force history and culture favoring "firewalling*, there is substantial risk that this approach would meet considerable resistance to

  8. Landslides risk mitigation along lifelines

    NASA Astrophysics Data System (ADS)

    Capparelli, G.; Versace, P.; Artese, G.; Costanzo, S.; Corsonello, P.; Di Massa, G.; Mendicino, G.; Maletta, D.; Leone, S.; Muto, F.; Senatore, A.; Troncone, A.; Conte, E.; Galletta, D.

    2012-04-01

    The paper describes an integrated, innovative and efficient solution to manage risk issues associated to landslides interfering with infrastructures. The research project was submitted for financial support in the framework of the Multi -regional Operational Programme 2007-13: Research and Competitiveness funded by the Ministry of Research (MIUR) and co-funded by the European Regional Development Fund. The project is aimed to developing and demonstrating an integrated system of monitoring, early warning and mitigation of landslides risk. The final goal is to timely identify potentially dangerous landslides, and to activate all needed impact mitigation measures, including the information delivery. The essential components of the system include monitoring arrays, telecommunication networks and scenario simulation models, assisted by a data acquisition and processing centre, and a traffic control centres. Upon integration, the system will be experimentally validated and demonstrated over ca. 200 km of three highway sections, crossing the regions of Campania, Basilicata, Calabria and Sicily. Progress in the state of art is represented by the developments in the field of environmental monitoring and in the mathematical modeling of landslides and by the development of services for traffic management. The approach to the problem corresponds to a "systemic logics" where each developed component foresees different interchangeable technological solutions to maximize the operational flexibility. The final system may be configured as a simple to complex structure, including different configurations to deal with different scenarios. Specifically, six different monitoring systems will be realized: three "point" systems, made up of a network of locally measuring sensors, and three "area" systems to remotely measure the displacements of large areas. Each network will be fully integrated and connected to a unique data transmission system. Standardized and shared procedures for the

  9. 2009 River Corridor Closure Contractor Revegetation and Mitigation Monitoring Report

    SciTech Connect

    C. T. Lindsey; K. A. Gano; R. D. Teel

    2009-09-30

    This document details the results of revegetation and mitigation monitoring conducted in 2009, including 25 revegetation/restoration projects, one revegetation/mitigation project, and three bat mitigation projects.

  10. Washington Tsunami Hazard Mitigation Program

    NASA Astrophysics Data System (ADS)

    Walsh, T. J.; Schelling, J.

    2012-12-01

    Washington State has participated in the National Tsunami Hazard Mitigation Program (NTHMP) since its inception in 1995. We have participated in the tsunami inundation hazard mapping, evacuation planning, education, and outreach efforts that generally characterize the NTHMP efforts. We have also investigated hazards of significant interest to the Pacific Northwest. The hazard from locally generated earthquakes on the Cascadia subduction zone, which threatens tsunami inundation in less than hour following a magnitude 9 earthquake, creates special problems for low-lying accretionary shoreforms in Washington, such as the spits of Long Beach and Ocean Shores, where high ground is not accessible within the limited time available for evacuation. To ameliorate this problem, we convened a panel of the Applied Technology Council to develop guidelines for construction of facilities for vertical evacuation from tsunamis, published as FEMA 646, now incorporated in the International Building Code as Appendix M. We followed this with a program called Project Safe Haven (http://www.facebook.com/ProjectSafeHaven) to site such facilities along the Washington coast in appropriate locations and appropriate designs to blend with the local communities, as chosen by the citizens. This has now been completed for the entire outer coast of Washington. In conjunction with this effort, we have evaluated the potential for earthquake-induced ground failures in and near tsunami hazard zones to help develop cost estimates for these structures and to establish appropriate tsunami evacuation routes and evacuation assembly areas that are likely to to be available after a major subduction zone earthquake. We intend to continue these geotechnical evaluations for all tsunami hazard zones in Washington.

  11. Mitigation of adverse environmental and unavoidable impacts

    SciTech Connect

    1995-10-01

    This portion of the Energy Vision 2020 draft report is a broad scope discussion of the mitigation of adverse environmental and unavoidable impacts. TVA will mitigate site specific environmental impacts from the construction and operation of new power facilities through a combination of planning, pollution prevention, and environmental controls. However, one of the most important mitigative measures associated with Energy Vision 2020 is the multi-attribute tradeoff method used for the evaluation. This method allowed proposed strategies to be reformated in order to reduce potential impacts.

  12. Forced Snaking

    NASA Astrophysics Data System (ADS)

    Ponedel, Benjamin; Knobloch, Edgar

    2016-11-01

    We study spatial localization in the real subcritical Ginzburg-Landau equation ut =m0 u +m1 cos2/π l x u +uxx +d | u | 2 u -| u | 4 u with spatially periodic forcing. When d > 0 and m1 = 0 this equation exhibits bistability between the trivial state u = 0 and a homogeneous nontrivial state u =u0 with stationary localized structures which accumulate at the Maxwell point m0 = - 3d2 / 16 . When spatial forcing is included its wavelength is imprinted on u0 creating conditions favorable to front pinning and hence spatial localization. We use numerical continuation to show that under appropriate conditions such forcing generates a sequence of localized states organized within a snakes-and-ladders structure centered on the Maxwell point, and refer to this phenomenon as forced snaking. We determine the stability properties of these states and show that longer lengthscale forcing leads to stationary trains consisting of a finite number of strongly localized, weakly interacting pulses exhibiting foliated snaking.

  13. Voluntary climate change mitigation actions of young adults: a classification of mitigators through latent class analysis.

    PubMed

    Korkala, Essi A E; Hugg, Timo T; Jaakkola, Jouni J K

    2014-01-01

    Encouraging individuals to take action is important for the overall success of climate change mitigation. Campaigns promoting climate change mitigation could address particular groups of the population on the basis of what kind of mitigation actions the group is already taking. To increase the knowledge of such groups performing similar mitigation actions we conducted a population-based cross-sectional study in Finland. The study population comprised 1623 young adults who returned a self-administered questionnaire (response rate 64%). Our aims were to identify groups of people engaged in similar climate change mitigation actions and to study the gender differences in the grouping. We also determined if socio-demographic characteristics can predict group membership. We performed latent class analysis using 14 mitigation actions as manifest variables. Three classes were identified among men: the Inactive (26%), the Semi-active (63%) and the Active (11%) and two classes among women: the Semi-active (72%) and the Active (28%). The Active among both genders were likely to have mitigated climate change through several actions, such as recycling, using environmentally friendly products, preferring public transport, and conserving energy. The Semi-Active had most probably recycled and preferred public transport because of climate change. The Inactive, a class identified among men only, had very probably done nothing to mitigate climate change. Among males, being single or divorced predicted little involvement in climate change mitigation. Among females, those without tertiary degree and those with annual income €≥16801 were less involved in climate change mitigation. Our results illustrate to what extent young adults are engaged in climate change mitigation, which factors predict little involvement in mitigation and give insight to which segments of the public could be the audiences of targeted mitigation campaigns.

  14. Voluntary Climate Change Mitigation Actions of Young Adults: A Classification of Mitigators through Latent Class Analysis

    PubMed Central

    Korkala, Essi A. E.; Hugg, Timo T.; Jaakkola, Jouni J. K.

    2014-01-01

    Encouraging individuals to take action is important for the overall success of climate change mitigation. Campaigns promoting climate change mitigation could address particular groups of the population on the basis of what kind of mitigation actions the group is already taking. To increase the knowledge of such groups performing similar mitigation actions we conducted a population-based cross-sectional study in Finland. The study population comprised 1623 young adults who returned a self-administered questionnaire (response rate 64%). Our aims were to identify groups of people engaged in similar climate change mitigation actions and to study the gender differences in the grouping. We also determined if socio-demographic characteristics can predict group membership. We performed latent class analysis using 14 mitigation actions as manifest variables. Three classes were identified among men: the Inactive (26%), the Semi-active (63%) and the Active (11%) and two classes among women: the Semi-active (72%) and the Active (28%). The Active among both genders were likely to have mitigated climate change through several actions, such as recycling, using environmentally friendly products, preferring public transport, and conserving energy. The Semi-Active had most probably recycled and preferred public transport because of climate change. The Inactive, a class identified among men only, had very probably done nothing to mitigate climate change. Among males, being single or divorced predicted little involvement in climate change mitigation. Among females, those without tertiary degree and those with annual income €≥16801 were less involved in climate change mitigation. Our results illustrate to what extent young adults are engaged in climate change mitigation, which factors predict little involvement in mitigation and give insight to which segments of the public could be the audiences of targeted mitigation campaigns. PMID:25054549

  15. Resilience Mitigation Financing for Water and Wastewater Utilities Webinar

    EPA Pesticide Factsheets

    The Resilience Mitigation Financing for Water and Wastewater Utilities webinar focuses on tools and financing resources to conduct resilience planning and to mitigate impacts before a disaster strikes.

  16. Intermolecular forces.

    PubMed

    Buckingham, A D

    1975-11-06

    The nature of molecular interactions is examined. Intermolecular forces are divided into long-range and short-range components; the former operate at distances where the effects of electron exchange are negligible and decrease as an inverse power of the separation. The long-range interactions may be subdividied into electrostatic, induction and dispersion contributions, where the electrostatic component is the interaction of the permanent charge distributions and the others originate in the fluctuations in the distributions. Typical magnitudes of the various contributions are given. The forces between macroscopic bodies are briefly considered, as are the effects of a medium. Some of the manifestations of molecular interactions are discussed.

  17. Implementing Financial Assurance for Mitigation Project Success

    EPA Pesticide Factsheets

    The Institute for Water Resources (IWR) prepared this white paper on financial assurance for mitigation project success to provide a reference resource for Corps district staff involved with establishing and overseeing financial assurances.

  18. 7 CFR 1794.17 - Mitigation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... (FONSI) and the Record of Decision (ROD). (b) Water and waste program. (1) Mitigation measures which... land use issues shall recognize the rights and responsibilities of landholders in making private...

  19. L-Reactor Habitat Mitigation Study

    SciTech Connect

    Not Available

    1988-02-01

    The L-Reactor Fish and Wildlife Resource Mitigation Study was conducted to quantify the effects on habitat of the L-Reactor restart and to identify the appropriate mitigation for these impacts. The completed project evaluated in this study includes construction of a 1000 acre reactor cooling reservoir formed by damming Steel Creek. Habitat impacts identified include a loss of approximately 3,700 average annual habitat units. This report presents a mitigation plan, Plan A, to offset these habitat losses. Plan A will offset losses for all species studied, except whitetailed deer. The South Carolina Wildlife and Marine Resources Department strongly recommends creation of a game management area to provide realistic mitigation for loss of deer habitats. 10 refs., 5 figs., 3 tabs. (MHB)

  20. On the road to HF mitigation

    SciTech Connect

    Van Zele, R.L.; Diener, R. )

    1990-07-01

    Two components were investigated as a part of tests run by Industry Cooperative HF Mitigation/Assessment Program (ICHMAP). This paper discusses how the test program included a vapor barrier component and an ambient impact assessment component.

  1. Mitigating the Impacts of Glint and Glare

    SciTech Connect

    Hillesheim, Michael; Kandt, Alicen; Phillips, Steven

    2015-09-01

    The National Renewable Energy Laboratory, supporting the Department of the Navy Renewable Energy Program Office, has developed an innovative glint/glare analysis and visualization methodology to understand and mitigate the possible impacts of light reflecting off solar photovoltaic arrays.

  2. 2008 Compensatory Mitigation Rule: General Requirements

    EPA Pesticide Factsheets

    Compensatory mitigation involves actions taken to offset unavoidable adverse impacts to wetlands, streams and other aquatic resources authorized by Clean Water Act section 404 permits and other Department of the Army (DA) permits

  3. Indoor Air Vapor Intrusion Mitigation Approaches

    EPA Pesticide Factsheets

    The National Risk Management Research Laboratory has developed a technology transfer document regarding management and treatment of vapor intrusion into building structures. This document describes the range of mitigation technologies available.

  4. Background on 2008 Compensatory Mitigation Rulemaking

    EPA Pesticide Factsheets

    In 2008 EPA and the Corps issued revised regulations governing compensatory mitigation for authorized impacts to wetlands, streams, and other waters of the U.S. under Section 404 of the Clean Water Act.

  5. Mission design considerations for nuclear risk mitigation

    NASA Technical Reports Server (NTRS)

    Stancati, Mike; Collins, John

    1993-01-01

    Strategies for the mitigation of the nuclear risk associated with two specific mission operations are discussed. These operations are the safe return of nuclear thermal propulsion reactors to earth orbit and the disposal of lunar/Mars spacecraft reactors.

  6. Training Chrysalis: Applications of Special Forces Training in the Development of the Objective Force

    DTIC Science & Technology

    2006-05-31

    TRAINING CHRYSALIS: APPLICATIONS OF SPECIAL FORCES TRAINING IN THE DEVELOPMENT OF THE OBJECTIVE FORCE A thesis presented to the Faculty of the U.S...Coleman, B.A. Accepted this 6th day of June 2003 by: , Director, Graduate Degree...Force O & O Operational and Organizational Plan PCS Permanent Change of Station POI Program of Instruction vii SERE Survival, Evasion, Resistance, and

  7. A conceptual framework for hydropeaking mitigation.

    PubMed

    Bruder, Andreas; Tonolla, Diego; Schweizer, Steffen P; Vollenweider, Stefan; Langhans, Simone D; Wüest, Alfred

    2016-10-15

    Hydropower plants are an important source of renewable energy. In the near future, high-head storage hydropower plants will gain further importance as a key element of large-scale electricity production systems. However, these power plants can cause hydropeaking which is characterized by intense unnatural discharge fluctuations in downstream river reaches. Consequences on environmental conditions in these sections are diverse and include changes to the hydrology, hydraulics and sediment regime on very short time scales. These altered conditions affect river ecosystems and biota, for instance due to drift and stranding of fishes and invertebrates. Several structural and operational measures exist to mitigate hydropeaking and the adverse effects on ecosystems, but estimating and predicting their ecological benefit remains challenging. We developed a conceptual framework to support the ecological evaluation of hydropeaking mitigation measures based on current mitigation projects in Switzerland and the scientific literature. We refined this framework with an international panel of hydropeaking experts. The framework is based on a set of indicators, which covers all hydrological phases of hydropeaking and the most important affected abiotic and biotic processes. Effects of mitigation measures on these indicators can be predicted quantitatively using prediction tools such as discharge scenarios and numerical habitat models. Our framework allows a comparison of hydropeaking effects among alternative mitigation measures, to the pre-mitigation situation, and to reference river sections. We further identified key issues that should be addressed to increase the efficiency of current and future projects. They include the spatial and temporal context of mitigation projects, the interactions of river morphology with hydropeaking effects, and the role of appropriate monitoring to evaluate the success of mitigation projects.

  8. Bioenergy as a Mitigation Measure

    NASA Astrophysics Data System (ADS)

    Dass, P.; Brovkin, V.; Müller, C.; Cramer, W.

    2011-12-01

    Numerous studies have shown that bioenergy, being one of the renewable energies with the lowest costs, is expected to play an important role in the near future as climate change mitigation measure. Current practices of converting crop products such as carbohydrates or plant oils to ethanol or biodiesel have limited capabilities to curb emission. Moreover, they compete with food production for the most fertile lands. Thus, second generation bioenergy technologies are being developed to process lignocellulosic plant materials from fast growing tree and grass species. A number of deforestation experiments using Earth System models have shown that in the mid- to high latitudes, deforested surface albedo strongly increases in presence of snow. This biophysical effect causes cooling, which could dominate over the biogeochemical warming effect because of the carbon emissions due to deforestation. In order to find out the global bioenergy potential of extensive plantations in the mid- to high latitudes, and the resultant savings in carbon emissions, we use the dynamic global vegetation model LPJmL run at a high spatial resolution of 0.5°. It represents both natural and managed ecosystems, including the cultivation of cellulosic energy crops. LPJmL is run with 21st century projections of climate and atmospheric CO2 concentration based on the IPCC-SRES business as usual or A2 scenario. Latitudes above 45° in both hemispheres are deforested and planted with crops having the highest bioenergy return for the respective pixels of the model. The rest of the Earth has natural vegetation. The agricultural management intensity values are used such that it results in the best approximation for 1999 - 2003 national yields of wheat and maize as reported by FAOSTAT 2009. Four different scenarios of land management are used ranging from an idealistic or best case scenario, where all limitations of soil and terrain properties are managed to the worst case scenario where none of these

  9. ENHANCED PRACTICAL PHOTOSYNTHETIC CO2 MITIGATION

    SciTech Connect

    Dr. Gregory Kremer; Dr. David J. Bayless; Dr. Morgan Vis; Dr. Michael Prudich; Dr. Keith Cooksey; Dr. Jeff Muhs

    2002-10-15

    This report documents significant achievements in the Enhanced Practical Photosynthetic CO{sub 2} Mitigation project during the period from 10/2/2001 through 10/01/2002. This report marks the end of year 2 of a three-year project as well as the milestone date for completion of Phase I activities. This report includes our current status and defines the steps being taken to ensure that we meet the project goals by the end of year 3. As indicated in the list of accomplishments below our current efforts are focused on evaluating candidate organisms and growth surfaces, preparing to conduct long-term tests in the bench-scale bioreactor test systems, and scaling-up the test facilities from bench scale to pilot scale. Specific results and accomplishments for the third quarter of 2002 include: Organisms and Growth Surfaces: (1) Test results continue to indicate that thermophilic cyanobacteria have significant advantages as agents for practical photosynthetic CO{sub 2} mitigation before mesophilic forms. (2) Additional thermal features with developed cyanobacterial mats, which might be calcium resistant, were found in YNP. (3) Back to back tests show that there is no detectable difference in the growth of isolate 1.2 s.c. (2) in standard and Ca-modified BG-11 medium. The doubling time for both cases was about 12 hours. (4) The cultivation of cyanobacteria in Ca-BG medium should proceed in the pH range between 7 and 7.4, but this suggestion requires additional experiments. (5) Cyanobacteria can be grown in media where sodium is present at trace levels. (6) Ca{sup 2+} enriched medium can be used as a sink for CO{sub 2} under alkaline conditions. (7) Cyanobacteria are able to generate cones of filaments on travertine surfaces. [Travertine is a mixture of CaCO{sub 3} and CaSO{sub 4}]. We hypothesize that SO{sub 4}{sup 2-} stimulates the generation of such cones, because they are not almost generated on CaCO3 surface. On the other hand, we know that plant gas contains elevated

  10. Problems with mitigation translocation of herpetofauna.

    PubMed

    Sullivan, Brian K; Nowak, Erika M; Kwiatkowski, Matthew A

    2015-02-01

    Mitigation translocation of nuisance animals is a commonly used management practice aimed at resolution of human-animal conflict by removal and release of an individual animal. Long considered a reasonable undertaking, especially by the general public, it is now known that translocated subjects are negatively affected by the practice. Mitigation translocation is typically undertaken with individual adult organisms and has a much lower success rate than the more widely practiced conservation translocation of threatened and endangered species. Nonetheless, the public and many conservation practitioners believe that because population-level conservation translocations have been successful that mitigation translocation can be satisfactorily applied to a wide variety of human-wildlife conflict situations. We reviewed mitigation translocations of reptiles, including our own work with 3 long-lived species (Gila monsters [Heloderma suspectum], Sonoran desert tortoises [Gopherus morafkai], and western diamond-backed rattlesnakes [Crotalus atrox]). Overall, mitigation translocation had a low success rate when judged either by effects on individuals (in all studies reviewed they exhibited increased movement or increased mortality) or by the success of the resolution of the human-animal conflict (translocated individuals often returned to the capture site). Careful planning and identification of knowledge gaps are critical to increasing success rates in mitigation translocations in the face of increasing pressure to find solutions for species threatened by diverse anthropogenic factors, including climate change and exurban and energy development.

  11. MITIGATION IMPACT SCREENING TOOL (MIST) | Science ...

    EPA Pesticide Factsheets

    MIST is intended to provide a back of the envelope, qualitative indication of the likely impacts of heat island mitigation strategies averaged at the city-scale. To run MIST, users follow three basic steps: 1. Select the city to model (240 available) 2. Define the mitigation strategy to test 3. Estimate impacts on meteorology, air quality, and energy The mitigation strategies investigated include increasing urban albedo, or increasing urban vegetative cover, or a combined approach. MIST also allows investigation of average temperature reduction and produces estimates of the resulting impacts on ozone and energy consumption. If a desired level of temperature reduction is identified, MIST allows the user to explore combinations of mitigation strategies that could achieve this reduction. MIST is intended to provide local-level air quality officials and nongovernment groups with qualitatively accurate assessments of the likely impacts of heat island mitigation strategies averaged at the city-scale. While results are estimated using state-of-the-science modeling tools, the results derived from this tool are qualitative in nature. The research upon which MIST is based necessarily incorporates a number of assumptions that help make the results applicable for a large number of cities and a variety of mitigation scenarios.

  12. Enhanced Practical Photosynthetic CO2 Mitigation

    SciTech Connect

    Gregory Kremer; David J. Bayless; Morgan Vis; Michael Prudich; Keith Cooksey; Jeff Muhs

    2003-07-22

    This quarterly report documents significant achievements in the Enhanced Practical Photosynthetic CO{sub 2} Mitigation project during the period from 4/2/2003 through 7/01/2003. As indicated in the list of accomplishments below we have completed some long-term model scale bioreactor tests and are prepared to begin pilot scale bioreactor testing. Specific results and accomplishments for the second quarter of 2003 include: (1) Bioreactor support systems and test facilities: (a) Qualitative long-term survivability tests for S.C.1.2(2) on Omnisil have been successfully completed and results demonstrate a growth rate that appears to be acceptable. (b) Quantitative tests of long-term growth productivity for S.C.1.2(2) on Omnisil have been completed and initial results are promising. Initial results show that the mass of organisms doubled (from 54.9 grams to 109.8 grams) in about 5 weeks. Full results will be available as soon as all membranes and filters are completely dried. The growth rate should increase significantly with the initiation of weekly harvesting during the long term tests. (c) The phase 1 construction of the pilot scale bioreactor has been completed, including the solar collector and light distribution system. We are now in the phase of system improvement as we wait for CRF-2 results in order to be able to finalize the design and construction of the pilot scale system. (d) A mass transfer experimental setup was constructed in order to measure the mass transfer rate from the gas to the liquid film flowing over a membrane and to study the hydrodynamics of the liquid film flowing over a membrane in the bioreactor. Results were reported for mass transfer coefficient, film thickness, and fluid velocity over an Omnisil membrane with a ''drilled hole'' header pipe design. (2) Organisms and Growth Surfaces: (a) A selectivity approach was used to obtain a cyanobacterial culture with elevated resistance to acid pH. Microlonies of ''3.2.2 S.C.1 Positive'' migrated

  13. Mitigation of arsenic-induced acquired cancer phenotype in prostate cancer stem cells by miR-143 restoration.

    PubMed

    Ngalame, Ntube N O; Makia, Ngome L; Waalkes, Michael P; Tokar, Erik J

    2016-12-01

    Inorganic arsenic, an environmental contaminant and a human carcinogen is associated with prostate cancer. Emerging evidence suggests that cancer stem cells (CSCs) are the driving force of carcinogenesis. Chronic arsenic exposure malignantly transforms the human normal prostate stem/progenitor cell (SC) line, WPE-stem to arsenic-cancer SCs (As-CSCs), through unknown mechanisms. MicroRNAs (miRNAs) are small, non-coding RNAs that negatively regulate gene expression at the posttranscriptional level. In prior work, miR-143 was markedly downregulated in As-CSCs, suggesting a role in arsenic-induced malignant transformation. In the present study, we investigated whether loss of miR-143 expression is important in arsenic-induced transformation of prostate SCs. Restoration of miR-143 in As-CSCs was achieved by lentivirus-mediated miR-143 overexpression. Cells were assessed bi-weekly for up to 30weeks to examine mitigation of cancer phenotype. Secreted matrix metalloproteinase (MMP) activity was increased by arsenic-induced malignant transformation, but miR-143 restoration decreased secreted MMP-2 and MMP-9 enzyme activities compared with scramble controls. Increased cell proliferation and apoptotic resistance, two hallmarks of cancer, were decreased upon miR-143 restoration. Increased apoptosis was associated with decreased BCL2 and BCL-XL expression. miR-143 restoration dysregulated the expression of SC/CSC self-renewal genes including NOTCH-1, BMI-1, OCT4 and ABCG2. The anticancer effects of miR-143 overexpression appeared to be mediated by targeting and inhibiting LIMK1 protein, and the phosphorylation of cofilin, a LIMK1 substrate. These findings clearly show that miR-143 restoration mitigated multiple cancer characteristics in the As-CSCs, suggesting a potential role in arsenic-induced transformation of prostate SCs. Thus, miR-143 is a potential biomarker and therapeutic target for arsenic-induced prostate cancer. Published by Elsevier Inc.

  14. Disruption mitigation by injection of small quantities of noble gas in ASDEX Upgrade

    NASA Astrophysics Data System (ADS)

    Pautasso, G.; Bernert, M.; Dibon, M.; Duval, B.; Dux, R.; Fable, E.; Fuchs, J. C.; Conway, G. D.; Giannone, L.; Gude, A.; Herrmann, A.; Hoelzl, M.; McCarthy, P. J.; Mlynek, A.; Maraschek, M.; Nardon, E.; Papp, G.; Potzel, S.; Rapson, C.; Sieglin, B.; Suttrop, W.; Treutterer, W.; The ASDEX Upgrade Team; The EUROfusion MST1 Team

    2017-01-01

    The most recent experiments of disruption mitigation by massive gas injection in ASDEX Upgrade have concentrated on small—relatively to the past—quantities of noble gas injected, and on the search for the minimum amount of gas necessary for the mitigation of the thermal loads on the divertor and for a significant reduction of the vertical force during the current quench. A scenario for the generation of a long-lived runaway electron beam has been established; this allows the study of runaway current dissipation by moderate quantities of argon injected. This paper presents these recent results and discusses them in the more general context of physical models and extrapolation, and of the open questions, relevant for the realization of the ITER disruption mitigation system.

  15. Disability correlates in Canadian Armed Forces Regular Force Veterans.

    PubMed

    Thompson, James M; Pranger, Tina; Sweet, Jill; VanTil, Linda; McColl, Mary Ann; Besemann, Markus; Shubaly, Colleen; Pedlar, David

    2015-01-01

    This study was undertaken to inform disability mitigation for military veterans by identifying personal, environmental, and health factors associated with activity limitations. A sample of 3154 Canadian Armed Forces Regular Force Veterans who were released during 1998-2007 participated in the 2010 Survey on Transition to Civilian Life. Associations between personal and environmental factors, health conditions and activity limitations were explored using ordinal logistic regression. The prevalence of activity reduction in life domains was higher than the Canadian general population (49% versus 21%), as was needing assistance with at least one activity of daily living (17% versus 5%). Prior to adjusting for health conditions, disability odds were elevated for increased age, females, non-degree post-secondary graduation, low income, junior non-commissioned members, deployment, low social support, low mastery, high life stress, and weak sense of community belonging. Reduced odds were found for private/recruit ranks. Disability odds were highest for chronic pain (10.9), any mental health condition (2.7), and musculoskeletal conditions (2.6), and there was a synergistic additive effect of physical and mental health co-occurrence. Disability, measured as activity limitation, was associated with a range of personal and environmental factors and health conditions, indicating multifactorial and multidisciplinary approaches to disability mitigation.

  16. A More Productive, But Different, Ocean After Mitigation

    NASA Astrophysics Data System (ADS)

    John, J. G.; Stock, C. A.; Dunne, J. P.

    2016-02-01

    Warming of the ocean surface under greenhouse gas (GHG) accumulation has been projected to enhance ocean stratification, exacerbate nutrient limitation of phytoplankton, and decrease marine net primary production (NPP) over the next century. Studies of the reversibility of warming further suggest a lagged recovery of global mean sea surface temperatures after GHG mitigation, suggesting that oceanic NPP may also be slow to rebound. In this study, we employ a mitigation scenario in which projected Representative Concentration Pathway (RCP8.5) forcings are applied out to 2100, and then reversed over the course of the following century in a fully coupled carbon-climate earth system model, and find an unexpected rapid increase in global mean NPP, including an "overshoot" to values above contemporary means. The 5.5% NPP overshoot is driven by a similar overshoot (11.8m) in the maximum monthly mixed layer depth arising from a transient imbalance between the cooling surface ocean and waters at intermediate depths ( 100-400m) that still carry strong legacy effects of warming in the 21st century. Residual warm subsurface waters at these depths weaken upper ocean density gradients, resulting in deeper mixing and enhanced surface nutrients despite the continued presence of significant legacy warming and freshening in surface waters. Enhanced surface nutrients combine with the positive effects of residual warming on phytoplankton growth and nutrient recycling to drive a global mean NPP overshoot. Regional variations in NPP reversibility exist however, and some regions experience prolonged suppression of NPP. We also find a marine ecosystem regime shift as stark depletion of silica at intermediate depths over the 21st century warming and mitigation period results in increased prevalence of large, non-diatom phytoplankton.

  17. Climate impacts of the ECLIPSE future emissions mitigation scenario

    NASA Astrophysics Data System (ADS)

    Baker, Laura; Collins, Bill; Olivie, Dirk; Cherian, Ribu; Quaas, Johannes; Myhre, Gunnar; Hodnebrog, Oivind; Skeie, Ragnhild

    2016-04-01

    We investigate the possible near-term climate benefits from mitigating aerosols, ozone and methane. The ECLIPSE (Evaluating the Climate and Air Quality Impacts of Short-Lived Pollutants) project developed a realistic emissions inventory based on current legislation for 2005-2050 (CLE), and a corresponding mitigation scenario designed to be beneficial for both air quality and short-term climate impact (MIT). We determine the climate impacts of the MIT scenario, focussing on the period 2040-2050. Four climate models with interactive chemistry and aerosols (HadGEM, NorESM, CESM-CAM4 and ECHAM-HAM) are used to provide multi-model ensembles of both atmosphere-only and coupled atmosphere-ocean simulations, to separate the effective radiative forcing (ERF) and the climate response. The ERFs are derived from the atmosphere-only simulations. In all models the MIT scenario leads to a negative global ERF which is driven mainly by methane emissions reductions. There is variability between models in the relative importance of methane and aerosol emissions reductions, and in the sign of ERF response to aerosol emissions reductions. The climate response to MIT is derived from the coupled simulations. In all models, MIT results in a decrease in the global mean temperature compared to CLE, with a model mean decrease of 0.22°C. The temperature decrease is seen most strongly in the Northern Hemisphere and is particularly strong in the Arctic. The ensembles of coupled-ocean simulations have therefore enabled us to identify a robust cooling signal from the air quality mitigation scenarios, which can be attributed to the different species using the ERFs.

  18. Analyzing costs of space debris mitigation methods

    NASA Astrophysics Data System (ADS)

    Wiedemann, C.; Krag, H.; Bendisch, J.; Sdunnus, H.

    The steadily increasing number of space objects poses a considerable hazard to all kinds of spacecraft. To reduce the risks to future space missions different debris mitigation measures and spacecraft protection techniques have been investigated during the last years. However, the economic efficiency has not been considered yet in this context. This economical background is not always clear to satellite operators and the space industry. Current studies have the objective to evaluate the mission costs due to space debris in a business as usual (no mitigation) scenario compared to the missions costs considering debris mitigation. The aim i an estimation of thes time until the investment in debris mitigation will lead to an effective reduction of mission costs. This paper presents the results of investigations on the key problems of cost estimation for spacecraft and the influence of debris mitigation and shielding on cost. The shielding of a satellite can be an effective method to protect the spacecraft against debris impact. Mitigation strategies like the reduction of orbital lifetime and de- or re-orbit of non-operational satellites are methods to control the space debris environment. These methods result in an increase of costs. In a first step the overall costs of different types of unmanned satellites are analyzed. The key problem is, that it is not possible to provide a simple cost model that can be applied to all types of satellites. Unmanned spacecraft differ very much in mission, complexity of design, payload and operational lifetime. It is important to classify relevant cost parameters and investigate their influence on the respective mission. The theory of empirical cost estimation and existing cost models are discussed. A selected cost model is simplified and generalized for an application on all operational satellites. In a next step the influence of space debris on cost is treated, if the implementation of mitigation strategies is considered.

  19. Destructive Interactions Between Mitigation Strategies and the Causes of Unexpected Failures in Natural Hazard Mitigation Systems

    NASA Astrophysics Data System (ADS)

    Day, S. J.; Fearnley, C. J.

    2013-12-01

    Large investments in the mitigation of natural hazards, using a variety of technology-based mitigation strategies, have proven to be surprisingly ineffective in some recent natural disasters. These failures reveal a need for a systematic classification of mitigation strategies; an understanding of the scientific uncertainties that affect the effectiveness of such strategies; and an understanding of how the different types of strategy within an overall mitigation system interact destructively to reduce the effectiveness of the overall mitigation system. We classify mitigation strategies into permanent, responsive and anticipatory. Permanent mitigation strategies such as flood and tsunami defenses or land use restrictions, are both costly and 'brittle': when they malfunction they can increase mortality. Such strategies critically depend on the accuracy of the estimates of expected hazard intensity in the hazard assessments that underpin their design. Responsive mitigation strategies such as tsunami and lahar warning systems rely on capacities to detect and quantify the hazard source events and to transmit warnings fast enough to enable at risk populations to decide and act effectively. Self-warning and voluntary evacuation is also usually a responsive mitigation strategy. Uncertainty in the nature and magnitude of the detected hazard source event is often the key scientific obstacle to responsive mitigation; public understanding of both the hazard and the warnings, to enable decision making, can also be a critical obstacle. Anticipatory mitigation strategies use interpretation of precursors to hazard source events and are used widely in mitigation of volcanic hazards. Their critical limitations are due to uncertainties in time, space and magnitude relationships between precursors and hazard events. Examples of destructive interaction between different mitigation strategies are provided by the Tohoku 2011 earthquake and tsunami; recent earthquakes that have impacted

  20. Comparing the impacts of mitigation and non-mitigation on mountain pine beetle populations.

    PubMed

    Coggins, Sam B; Coops, Nicholas C; Wulder, Michael A; Bater, Christopher W; Ortlepp, Stephanie M

    2011-01-01

    Mountain pine beetles, Dendroctonus ponderosae (Hopkins) attack and can ultimately kill individuals and groups of pine trees, specifically lodgepole pine (Pinus contorta Dougl. ex. Loud var. latifolia Engl.). In British Columbia, beetle attack has increased from 164 000 ha in 1999 to over 13 million ha in 2008. Mitigation efforts can play a key role in addressing the impact beetle infestations can have on the forested landscape. In this research, the impact of mitigation on a mountain pine beetle infestation is examined within a network of 28 research plots where sanitation harvesting was completed (10 mitigated plots) and not completed (18 unmitigated plots). Three forest stand level modelling scenarios which predict the number of attacked trees, based on current infestation within the plots, were utilized to compare the differences between mitigated and non-mitigated plots. In the first scenario in the non-mitigated plots, 125 trees were infested after 10 years, while in the mitigated plots no trees were infested in the same time period. The second scenario indicates the level of mitigation required to suppress beetle infestations where the proportion of mitigated trees was calculated for each plot by counting the residual attack and the number of mitigated trees. The average mitigation rate over all plots of 43% (range 0-100%) is not sufficient to provide control. In the non-mitigated plots, the average population expansion rate was 5 (range of 0-18) which requires a detection accuracy of 74% to reliably detect infestation. The third scenario estimated the length of time required for ongoing detection, monitoring, and mitigation to bring an infestation under control. If mitigation efforts were maintained at the current rate of 43%, the beetle population would not be adequately controlled. However, when aided by continued detection and monitoring of attacked trees, mitigation rates greater than 50% are sufficient to control infestations, especially with

  1. Force decomposition in robot force control

    NASA Technical Reports Server (NTRS)

    Murphy, Steve H.; Wen, John T.

    1991-01-01

    The unit inconsistency in force decomposition has motivated an investigation into the force control problem in multiple-arm manipulation. Based on physical considerations, it is argued that the force that should be controlled is the internal force at the specified frame in the payload. This force contains contributions due to both applied forces from the arms and the inertial force from the payload and the arms. A least-squares scheme free of unit inconsistency for finding this internal force is presented. The force control issue is analyzed, and an integral force feedback controller is proposed.

  2. 44 CFR 78.6 - Flood Mitigation Plan approval process.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Flood Mitigation Plan..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program FLOOD MITIGATION ASSISTANCE § 78.6 Flood Mitigation Plan approval process. The State POC will forward all Flood...

  3. 44 CFR 78.6 - Flood Mitigation Plan approval process.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 44 Emergency Management and Assistance 1 2011-10-01 2011-10-01 false Flood Mitigation Plan..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program FLOOD MITIGATION ASSISTANCE § 78.6 Flood Mitigation Plan approval process. The State POC will forward all Flood...

  4. 44 CFR 78.6 - Flood Mitigation Plan approval process.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 44 Emergency Management and Assistance 1 2014-10-01 2014-10-01 false Flood Mitigation Plan..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program FLOOD MITIGATION ASSISTANCE § 78.6 Flood Mitigation Plan approval process. The State POC will forward all Flood...

  5. 44 CFR 78.6 - Flood Mitigation Plan approval process.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 44 Emergency Management and Assistance 1 2012-10-01 2011-10-01 true Flood Mitigation Plan approval..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program FLOOD MITIGATION ASSISTANCE § 78.6 Flood Mitigation Plan approval process. The State POC will forward all Flood...

  6. 44 CFR 78.6 - Flood Mitigation Plan approval process.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 44 Emergency Management and Assistance 1 2013-10-01 2013-10-01 false Flood Mitigation Plan..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program FLOOD MITIGATION ASSISTANCE § 78.6 Flood Mitigation Plan approval process. The State POC will forward all Flood...

  7. 8 CFR 280.5 - Mitigation or remission of fines.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Mitigation or remission of fines. 280.5... AND COLLECTION OF FINES § 280.5 Mitigation or remission of fines. In any case in which mitigation or... Examinations, or the Director for the National Fines Office for such mitigation or remission. ...

  8. 46 CFR 272.32 - Mitigation of penalty.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Mitigation of penalty. 272.32 Section 272.32 Shipping... REPAIR SUBSIDY Penalties § 272.32 Mitigation of penalty. The Director, Office of Ship Operating Assistance, may decide, after a non-emergency foreign repair occurs, to mitigate the penalty. Any mitigation...

  9. 44 CFR 78.5 - Flood Mitigation Plan development.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 44 Emergency Management and Assistance 1 2013-10-01 2013-10-01 false Flood Mitigation Plan development. 78.5 Section 78.5 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY... MITIGATION ASSISTANCE § 78.5 Flood Mitigation Plan development. A Flood Mitigation Plan will articulate a...

  10. 44 CFR 78.5 - Flood Mitigation Plan development.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 44 Emergency Management and Assistance 1 2011-10-01 2011-10-01 false Flood Mitigation Plan development. 78.5 Section 78.5 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY... MITIGATION ASSISTANCE § 78.5 Flood Mitigation Plan development. A Flood Mitigation Plan will articulate a...

  11. 44 CFR 78.5 - Flood Mitigation Plan development.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 44 Emergency Management and Assistance 1 2014-10-01 2014-10-01 false Flood Mitigation Plan development. 78.5 Section 78.5 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY... MITIGATION ASSISTANCE § 78.5 Flood Mitigation Plan development. A Flood Mitigation Plan will articulate a...

  12. Strategic forces

    SciTech Connect

    Not Available

    1990-10-01

    The Air Force now plans to retain the Minuteman II and III missile force through fiscal year 2008. Introduced about 25 years ago, these missiles have served as a nuclear deterrence for longer than initially envisioned. Over the extended lives of the systems, questions have arisen over their continued reliability and operational effectiveness, particularly the Minuteman II system. Limited flight testing, due to a shortage of test missiles, and reduced reliability caused by age-related deterioration of guidance computers and propulsion motors are two factors undermining confidence in the Minuteman II. GAO believes that the Minuteman II could be retired before 1998 as presently contemplated under an assumption of a Strategic Arms Reduction Talks agreement. An alternative would be to reinstate the Air Force's plans to replace deteriorated missile components and acquire the assets needed to resume flight testing at rates necessary to restore and sustain confidence in the system's performance through fiscal year 2008. However, on the basis of current test schedules, GAO is concerned that components to test the missile's warheads will be depleted by about 1999.

  13. Playing against nature: improving earthquake hazard mitigation

    NASA Astrophysics Data System (ADS)

    Stein, S. A.; Stein, J.

    2012-12-01

    The great 2011 Tohoku earthquake dramatically demonstrated the need to improve earthquake and tsunami hazard assessment and mitigation policies. The earthquake was much larger than predicted by hazard models, and the resulting tsunami overtopped coastal defenses, causing more than 15,000 deaths and $210 billion damage. Hence if and how such defenses should be rebuilt is a challenging question, because the defences fared poorly and building ones to withstand tsunamis as large as March's is too expensive,. A similar issue arises along the Nankai Trough to the south, where new estimates warning of tsunamis 2-5 times higher than in previous models raise the question of what to do, given that the timescale on which such events may occur is unknown. Thus in the words of economist H. Hori, "What should we do in face of uncertainty? Some say we should spend our resources on present problems instead of wasting them on things whose results are uncertain. Others say we should prepare for future unknown disasters precisely because they are uncertain". Thus society needs strategies to mitigate earthquake and tsunami hazards that make economic and societal sense, given that our ability to assess these hazards is poor, as illustrated by highly destructive earthquakes that often occur in areas predicted by hazard maps to be relatively safe. Conceptually, we are playing a game against nature "of which we still don't know all the rules" (Lomnitz, 1989). Nature chooses tsunami heights or ground shaking, and society selects the strategy to minimize the total costs of damage plus mitigation costs. As in any game of chance, we maximize our expectation value by selecting the best strategy, given our limited ability to estimate the occurrence and effects of future events. We thus outline a framework to find the optimal level of mitigation by balancing its cost against the expected damages, recognizing the uncertainties in the hazard estimates. This framework illustrates the role of the

  14. Measurement of agitation force in dissolution test and mechanical destructive force in disintegration test.

    PubMed

    Kamba, Masaharu; Seta, Yasuo; Takeda, Nao; Hamaura, Takeshi; Kusai, Akira; Nakane, Hisanori; Nishimura, Kenji

    2003-01-02

    The purpose of this study was to investigate the effect of the agitation force and mechanical destructive force on the drug dissolution of a tablet in the paddle rotation dissolution test and in the disintegration test. The agitation in the paddle method and the mechanical destructive force in the disintegration test were considered to be conclusive factors for drug dissolution. The dissolution rate of planar-constant-release tablets increased with increasing paddle rotation speed and increased with increasing distance from the center of the vessel bottom. Separately, the fluid resistance (agitation force) in the vessel was measured using a modified paddle method apparatus equipped with a fluid resistance sensor. The fluid resistance was 0.03 x 10(-3) N/(64 mm(2)) when the paddle rotation speed was 50 rpm at a position 4 mm away from the center. A considerable position-dependent change in agitation force intensity was seen with the fluid resistance sensor. The impulsive force (mechanical destructive force) in the disintegration test apparatus was measured using a modified basket-rack assembly with a strain gauge transducer. The fluid resistance was measured using the basket-rack assembly with a different sensor probe and amplifier. The impulsive force applied by the auxiliary disk was 0.31 N and the fluid resistance at the bottom of the basket-rack assembly was 1.66 x 10(-3) N/(64 mm(2)).

  15. PHYSICS PROCESSES IN DISRUPTION MITIGATION USING MASSIVE NOBLE GAS INJECTION

    SciTech Connect

    D.A. HUMPHREYS; D.G. WHYTE; T.C. JERNIGAN; T.E.EVANS; D.S. GRAY; E.M. HOLLMANN; A.W. HYATT; A.G. KELLMAN; C.J. LASNIER; P.B. PARKS; P.L. TAYLOR

    2002-07-01

    Methods for detecting imminent disruptions and mitigating disruption effects using massive injection of noble gases (He, Ne, or Ar) have been demonstrated on the DIII-D tokamak [1]. A jet of high injected gas density (> 10{sup 24} m{sup -3}) and pressure (> 20 kPa) penetrates the target plasma at the gas sound speed ({approx}300-500 m/s) and increases the atom/ion content of the plasma by a factor of > 50 in several milliseconds. UV line radiation from the impurity species distributes the plasma energy uniformly on the first wall, reducing the thermal load to the divertor by a factor of 10. Runaway electrons are almost completely eliminated by the large density of free and bound electrons supplied by the gas injection. The small vertical plasma displacement before current quench and high ratio of current decay rate to vertical growth rate result in a 75% reduction in peak halo current amplitude and attendant forces.

  16. National Wetland Mitigation Banking Study. Commercial Wetland Mitigation Credit Markets: Theory and Practice.

    DTIC Science & Technology

    1995-11-01

    Richard Reppert, Institute for Water Resources. This report provides general background information and concepts pertaining to wetland mitigation banking... Water Resources. This report presents bank- specific information obtained in an inventory of banks and detailed case study histories, an annotated...Brumbaugh and Richard Reppert, Institute for Water Resources. Summation offindings of phase one of the National Wetland Mitigation Banking Study. Examination

  17. On the road to HF mitigation

    SciTech Connect

    VanZele, R.L.; Diener, R. )

    1990-06-01

    The hazards of hydrogen fluoride (HF) have long been recognized and industry performance reflects sound operating practices. However, full-scale industry-sponsored HF release test conducted at the U.S. Department of Energy (DOE) test site in 1986 caused concern in view of HF's toxicity. Ambient impacts were greater than anticipated. And diking, a primary mitigation technique, proved ineffective for releases of pressurized superheated HF. In partial response to these new technical data, an ad-hoc three-component Industry Cooperative Hydrogen Fluoride Mitigation Assessment Program (ICHMAP) was begun in late 1987 to study and test techniques for mitigating accidental releases of HF and alkylation unit acid (AUA) and to enhance capabilities to estimate ambient impacts from such releases. AUA is a mixture of HF and hydrocarbons. The program's mitigation components have recently been completed while work on the impact assessment component is nearing completion. This article describes the program and summarizes the objective, scope of work, structure, and conclusions from the program's two mitigation components. In addition, the objectives and scope of work of the impact assessment components are described.

  18. Climate change 2007 - mitigation of climate change

    SciTech Connect

    Metz, B.; Davidson, O.; Bosch, P.; Dave, R.; Meyer, L.

    2007-07-01

    This volume of the Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC) provides a comprehensive, state-of-the-art and worldwide overview of scientific knowledge related to the mitigation of climate change. It includes a detailed assessment of costs and potentials of mitigation technologies and practices, implementation barriers, and policy options for the sectors: energy supply, transport, buildings, industry, agriculture, forestry and waste management. It links sustainable development policies with climate change practices. This volume will again be the standard reference for all those concerned with climate change. Contents: Foreword; Preface; Summary for policymakers; Technical Summary; 1. Introduction; 2. Framing issues; 3. Issues related to mitigation in the long term context; 4. Energy supply; 5. Transport and its infrastructure; 6. Residential and commercial buildings; 7. Industry; 8. Agriculture; 9. Forestry; 10. Waste management; 11. Mitigation from a cross sectoral perspective; 12. Sustainable development and mitigation; 13. Policies, instruments and co-operative agreements. 300 figs., 50 tabs., 3 annexes.

  19. The ESA Space Debris Mitigation Handbook 2002

    NASA Astrophysics Data System (ADS)

    Klinkrad, H.; Beltrami, P.; Hauptmann, S.; Martin, C.; Sdunnus, H.; Stokes, H.; Walker, R.; Wilkinson, J.

    2004-01-01

    The ESA Space Debris Mitigation Handbook 2002 was jointly produced by an industrial consortium and ESA, under an ESA contract. The Handbook is a non-regulatory, self-standing document, providing technical information in support of European debris mitigation standards. The necessity of debris mitigation is illustrated in the context of historic launch activities and operational practices, which led to the current debris environment, with corresponding collision flux levels. Based on detailed population evolution models, this initial population is analyzed with respect to its growth and stability under different traffic assumptions. The implementation of debris mitigation measures, in particular the de-orbiting of spacecraft and upper stages, is shown to reduce the debris growth to an acceptable level within a few decades. The risk on ground due to re-entering space objects, its assessment, and its control is also analyzed. For on-orbit systems, collision risk reduction by avoidance manoeuvres, and passive protection by shielding is outlined. ESA's Handbook also compares recommended debris mitigation and risk reduction practices proposed by several other space agencies. The Handbook will be available at the begin of 2003.

  20. The ESA Space Debris Mitigation Handbook 2002

    NASA Astrophysics Data System (ADS)

    Klinkrad, H.; Beltrami, P.; Hauptmann, S.; Martin, C.; Sdunnus, H.; Stokes, H.; Walker, R.; Wilkinson, J.

    The ESA Space Debris Mitigation Handbook 2002 was jointly produced by an industrial consortium and ESA, under an ESA contract. The Handbook is a non-regulatory, self-standing document, providing technical information in support of European debris mitigation standards. The necessity of debris mitigation is illustrated in the context of historic launch activities and operational practices, which led to the current debris environment, with corresponding collision flux levels. Based on detailed population evolution models, this initial population is analysed with respect to its growth and stability under different traffic assumptions. The implementation of debris mitigation measures, in particular the de-orbiting of spacecraft and upper stages, is shown to reduce the debris growth to an acceptable level within a few decades. The risk on ground due to re-entering space objects, its assessment, and its control is also analysed. For on-orbit systems, collision risk reduction by avoidance manoeuvres, and passive protection by shielding is outlined. ESA's Handbook also compares recommended debris mitigation and risk reduction practices proposed by several other space agencies. The Handbook will be available by the end of 2002.

  1. Bio-inspired heterogeneous composites for broadband vibration mitigation

    PubMed Central

    Chen, Yanyu; Wang, Lifeng

    2015-01-01

    Structural biological materials have developed heterogeneous and hierarchical architectures that are responsible for the outstanding performance to provide protection against environmental threats including static and dynamic loading. Inspired by this observation, this research aims to develop new material and structural concepts for broadband vibration mitigation. The proposed composite materials possess a two-layered heterogeneous architecture where both layers consist of high-volume platelet-shape reinforcements and low-volume matrix, similar to the well-known “brick and mortar” microstructure of biological composites. Using finite element method, we numerically demonstrated that broadband wave attenuation zones can be achieved by tailoring the geometric features of the heterogeneous architecture. We reveal that the resulting broadband attenuation zones are gained by directly superimposing the attenuation zones in each constituent layer. This mechanism is further confirmed by the investigation into the phonon dispersion relation of each layer. Importantly, the broadband wave attenuation capability will be maintained when the mineral platelet orientation is locally manipulated, yet a contrast between the mineral platelet concentrations of the two constituent layers is essential. The findings of this work will provide new opportunities to design heterogeneous composites for broadband vibration mitigation and impact resistance under mechanically challenging environmental conditions. PMID:26642932

  2. Bio-inspired heterogeneous composites for broadband vibration mitigation.

    PubMed

    Chen, Yanyu; Wang, Lifeng

    2015-12-08

    Structural biological materials have developed heterogeneous and hierarchical architectures that are responsible for the outstanding performance to provide protection against environmental threats including static and dynamic loading. Inspired by this observation, this research aims to develop new material and structural concepts for broadband vibration mitigation. The proposed composite materials possess a two-layered heterogeneous architecture where both layers consist of high-volume platelet-shape reinforcements and low-volume matrix, similar to the well-known "brick and mortar" microstructure of biological composites. Using finite element method, we numerically demonstrated that broadband wave attenuation zones can be achieved by tailoring the geometric features of the heterogeneous architecture. We reveal that the resulting broadband attenuation zones are gained by directly superimposing the attenuation zones in each constituent layer. This mechanism is further confirmed by the investigation into the phonon dispersion relation of each layer. Importantly, the broadband wave attenuation capability will be maintained when the mineral platelet orientation is locally manipulated, yet a contrast between the mineral platelet concentrations of the two constituent layers is essential. The findings of this work will provide new opportunities to design heterogeneous composites for broadband vibration mitigation and impact resistance under mechanically challenging environmental conditions.

  3. Bio-inspired heterogeneous composites for broadband vibration mitigation

    NASA Astrophysics Data System (ADS)

    Chen, Yanyu; Wang, Lifeng

    2015-12-01

    Structural biological materials have developed heterogeneous and hierarchical architectures that are responsible for the outstanding performance to provide protection against environmental threats including static and dynamic loading. Inspired by this observation, this research aims to develop new material and structural concepts for broadband vibration mitigation. The proposed composite materials possess a two-layered heterogeneous architecture where both layers consist of high-volume platelet-shape reinforcements and low-volume matrix, similar to the well-known “brick and mortar” microstructure of biological composites. Using finite element method, we numerically demonstrated that broadband wave attenuation zones can be achieved by tailoring the geometric features of the heterogeneous architecture. We reveal that the resulting broadband attenuation zones are gained by directly superimposing the attenuation zones in each constituent layer. This mechanism is further confirmed by the investigation into the phonon dispersion relation of each layer. Importantly, the broadband wave attenuation capability will be maintained when the mineral platelet orientation is locally manipulated, yet a contrast between the mineral platelet concentrations of the two constituent layers is essential. The findings of this work will provide new opportunities to design heterogeneous composites for broadband vibration mitigation and impact resistance under mechanically challenging environmental conditions.

  4. Delayed detection of climate mitigation benefits due to climate inertia and variability.

    PubMed

    Tebaldi, Claudia; Friedlingstein, Pierre

    2013-10-22

    Climate change mitigation acts by reducing greenhouse gas emissions, and thus curbing, or even reversing, the increase in their atmospheric concentration. This reduces the associated anthropogenic radiative forcing, and hence the size of the warming. Because of the inertia and internal variability affecting the climate system and the global carbon cycle, it is unlikely that a reduction in warming would be immediately discernible. Here we use 21st century simulations from the latest ensemble of Earth System Model experiments to investigate and quantify when mitigation becomes clearly discernible. We use one of the scenarios as a reference for a strong mitigation strategy, Representative Concentration Pathway (RCP) 2.6 and compare its outcome with either RCP4.5 or RCP8.5, both of which are less severe mitigation pathways. We analyze global mean atmospheric CO2, and changes in annually and seasonally averaged surface temperature at global and regional scales. For global mean surface temperature, the median detection time of mitigation is about 25-30 y after RCP2.6 emissions depart from the higher emission trajectories. This translates into detection of a mitigation signal by 2035 or 2045, depending on whether the comparison is with RCP8.5 or RCP4.5, respectively. The detection of climate benefits of emission mitigation occurs later at regional scales, with a median detection time between 30 and 45 y after emission paths separate. Requiring a 95% confidence level induces a delay of several decades, bringing detection time toward the end of the 21st century.

  5. Delayed detection of climate mitigation benefits due to climate inertia and variability

    PubMed Central

    Tebaldi, Claudia; Friedlingstein, Pierre

    2013-01-01

    Climate change mitigation acts by reducing greenhouse gas emissions, and thus curbing, or even reversing, the increase in their atmospheric concentration. This reduces the associated anthropogenic radiative forcing, and hence the size of the warming. Because of the inertia and internal variability affecting the climate system and the global carbon cycle, it is unlikely that a reduction in warming would be immediately discernible. Here we use 21st century simulations from the latest ensemble of Earth System Model experiments to investigate and quantify when mitigation becomes clearly discernible. We use one of the scenarios as a reference for a strong mitigation strategy, Representative Concentration Pathway (RCP) 2.6 and compare its outcome with either RCP4.5 or RCP8.5, both of which are less severe mitigation pathways. We analyze global mean atmospheric CO2, and changes in annually and seasonally averaged surface temperature at global and regional scales. For global mean surface temperature, the median detection time of mitigation is about 25–30 y after RCP2.6 emissions depart from the higher emission trajectories. This translates into detection of a mitigation signal by 2035 or 2045, depending on whether the comparison is with RCP8.5 or RCP4.5, respectively. The detection of climate benefits of emission mitigation occurs later at regional scales, with a median detection time between 30 and 45 y after emission paths separate. Requiring a 95% confidence level induces a delay of several decades, bringing detection time toward the end of the 21st century. PMID:24101485

  6. The Impact of Future Carbon Mitigation Policies and Climate on Regional Air Qaulity

    NASA Astrophysics Data System (ADS)

    Turnock, Steven; O'Connor, Fiona; Smith, Steven

    2017-04-01

    Air pollutants (ozone and particulate matter) can affect both climate and air quality. Future reductions in the anthropogenic emissions of air pollutants and their precursors will improve air quality. However, it is uncertain the extent to which the choice of carbon mitigation policies could influence future regional air quality via changes to the co-emission of air pollutants from carbon sources. In addition, it is still uncertain how future changes in climate could influence air pollutants and future air quality may change through climate mitigation itself. Two consistent future scenarios, developed by the same integrated assessment model, are used within this study: one is a reference scenario of future economic development and population growth, whilst the other (RCP4.5) assumes the same development but applies mitigation measures to reduce carbon dioxide concentrations and stabilise anthropogenic radiative forcing at 4.5 W m-2. Here we have applied these two emission scenarios to a coupled composition-climate model (HadGEM3-UKCA) to ascertain the impact of such carbon mitigation measures on future air quality, both globally and over specific regions, such as Europe and Asia. A comparison of the emission scenarios shows that the implementation of carbon mitigation measures reduces global air pollutant emissions by between 15-30% and by larger amounts over other regions. Additional simulations have also been undertaken to attribute the future air quality changes to either reductions in emissions or changes in climate. An evaluation of the model using air quality observations has also been undertaken for the year 2000. This study demonstrates that carbon mitigation policies to mitigate climate change have added co-benefits for global and regional air quality.

  7. Future Arctic climate changes: Adaptation and mitigation time scales

    NASA Astrophysics Data System (ADS)

    Overland, James E.; Wang, Muyin; Walsh, John E.; Stroeve, Julienne C.

    2014-02-01

    The climate in the Arctic is changing faster than in midlatitudes. This is shown by increased temperatures, loss of summer sea ice, earlier snow melt, impacts on ecosystems, and increased economic access. Arctic sea ice volume has decreased by 75% since the 1980s. Long-lasting global anthropogenic forcing from carbon dioxide has increased over the previous decades and is anticipated to increase over the next decades. Temperature increases in response to greenhouse gases are amplified in the Arctic through feedback processes associated with shifts in albedo, ocean and land heat storage, and near-surface longwave radiation fluxes. Thus, for the next few decades out to 2040, continuing environmental changes in the Arctic are very likely, and the appropriate response is to plan for adaptation to these changes. For example, it is very likely that the Arctic Ocean will become seasonally nearly sea ice free before 2050 and possibly within a decade or two, which in turn will further increase Arctic temperatures, economic access, and ecological shifts. Mitigation becomes an important option to reduce potential Arctic impacts in the second half of the 21st century. Using the most recent set of climate model projections (CMIP5), multimodel mean temperature projections show an Arctic-wide end of century increase of +13°C in late fall and +5°C in late spring for a business-as-usual emission scenario (RCP8.5) in contrast to +7°C in late fall and +3°C in late spring if civilization follows a mitigation scenario (RCP4.5). Such temperature increases demonstrate the heightened sensitivity of the Arctic to greenhouse gas forcing.

  8. A Super Energy Mitigation Nanostructure at High Impact Speed Based on Buckyball System

    PubMed Central

    Xu, Jun; Li, Yibing; Xiang, Yong; Chen, Xi

    2013-01-01

    The energy mitigation properties of buckyballs are investigated using molecular dynamics (MD) simulations. A one dimensional buckyball long chain is employed as a unit cell of granular fullerene particles. Two types of buckyballs i.e. C60 and C720 with recoverable and non-recoverable behaviors are chosen respectively. For C60 whose deformation is relatively small, a dissipative contact model is proposed. Over 90% of the total impact energy is proven to be mitigated through interfacial reflection of wave propagation, the van der Waals interaction, covalent potential energy and atomistic kinetic energy evidenced by the decent force attenuation and elongation of transmitted impact. Further, the C720 system is found to outperform its C60 counterpart and is able to mitigate over 99% of the total kinetic energy by using a much shorter chain thanks to its non-recoverable deformation which enhances the four energy dissipation terms. Systematic studies are carried out to elucidate the effects of impactor speed and mass, as well as buckyball size and number on the system energy mitigation performance. This one dimensional buckyball system is especially helpful to deal with the impactor of high impact speed but small mass. The results may shed some lights on the research of high-efficiency energy mitigation material selections and structure designs. PMID:23724082

  9. A super energy mitigation nanostructure at high impact speed based on buckyball system.

    PubMed

    Xu, Jun; Li, Yibing; Xiang, Yong; Chen, Xi

    2013-01-01

    The energy mitigation properties of buckyballs are investigated using molecular dynamics (MD) simulations. A one dimensional buckyball long chain is employed as a unit cell of granular fullerene particles. Two types of buckyballs i.e. C60 and C720 with recoverable and non-recoverable behaviors are chosen respectively. For C60 whose deformation is relatively small, a dissipative contact model is proposed. Over 90% of the total impact energy is proven to be mitigated through interfacial reflection of wave propagation, the van der Waals interaction, covalent potential energy and atomistic kinetic energy evidenced by the decent force attenuation and elongation of transmitted impact. Further, the C720 system is found to outperform its C60 counterpart and is able to mitigate over 99% of the total kinetic energy by using a much shorter chain thanks to its non-recoverable deformation which enhances the four energy dissipation terms. Systematic studies are carried out to elucidate the effects of impactor speed and mass, as well as buckyball size and number on the system energy mitigation performance. This one dimensional buckyball system is especially helpful to deal with the impactor of high impact speed but small mass. The results may shed some lights on the research of high-efficiency energy mitigation material selections and structure designs.

  10. New Methods of Energy Efficient Radon Mitigation

    SciTech Connect

    Fisk, W.J.; Prill, R.J.; Wooley, J.; Bonnefous, Y.C.; Gadgil, A.J.; Riley, W.J.

    1994-05-01

    Two new radon mitigation techniques are introduced and their evaluation in a field study complemented by numerical model predictions is described. Based on numerical predictions, installation of a sub gravel membrane at the study site resulted in a factor of two reduction in indoor radon concentrations. Experimental data indicated that installation of 'short-circuit' pipes extending between the subslab gravel and outdoors, caused an additional factor of two decrease in the radon concentration. Consequently, the combination of these two passive radon mitigation features, called the membrane and short-circuit (MASC) technique, was associated with a factor of four reduction in indoor radon concentration. The energy-efficient active radon mitigation method, called efficient active subslab pressurization (EASP), required only 20% of the fan energy of conventional active subslab depressurization and reduced the indoor radon concentration by approximately a factor of 15, including the numerically-predicted impact of the sub-gravel membrane.

  11. Space options for tropical cyclone hazard mitigation

    NASA Astrophysics Data System (ADS)

    Dicaire, Isabelle; Nakamura, Ryoko; Arikawa, Yoshihisa; Okada, Kazuyuki; Itahashi, Takamasa; Summerer, Leopold

    2015-02-01

    This paper investigates potential space options for mitigating the impact of tropical cyclones on cities and civilians. Ground-based techniques combined with space-based remote sensing instrumentation are presented together with space-borne concepts employing space solar power technology. Two space-borne mitigation options are considered: atmospheric warming based on microwave irradiation and laser-induced cloud seeding based on laser power transfer. Finally technology roadmaps dedicated to the space-borne options are presented, including a detailed discussion on the technological viability and technology readiness level of our proposed systems. Based on these assessments, the space-borne cyclone mitigation options presented in this paper may be established in a quarter of a century.

  12. Earthquake Hazard Mitigation Strategy in Indonesia

    NASA Astrophysics Data System (ADS)

    Karnawati, D.; Anderson, R.; Pramumijoyo, S.

    2008-05-01

    Because of the active tectonic setting of the region, the risks of geological hazards inevitably increase in Indonesian Archipelagoes and other ASIAN countries. Encouraging community living in the vulnerable area to adapt with the nature of geology will be the most appropriate strategy for earthquake risk reduction. Updating the Earthquake Hazard Maps, enhancement ofthe existing landuse management , establishment of public education strategy and method, strengthening linkages among stake holders of disaster mitigation institutions as well as establishement of continues public consultation are the main strategic programs for community resilience in earthquake vulnerable areas. This paper highlights some important achievements of Earthquake Hazard Mitigation Programs in Indonesia, together with the difficulties in implementing such programs. Case examples of Yogyakarta and Bengkulu Earthquake Mitigation efforts will also be discussed as the lesson learned. The new approach for developing earthquake hazard map which is innitiating by mapping the psychological aspect of the people living in vulnerable area will be addressed as well.

  13. Disruption mitigation studies in DIII-D

    SciTech Connect

    Taylor, P.L.; Kellman, A.G.; Evans, T.E.

    1999-01-01

    Data on the discharge behavior, thermal loads, halo currents, and runaway electrons have been obtained in disruptions on the DIII-D tokamak. These experiments have also evaluated techniques to mitigate the disruptions while minimizing runaway electron production. Experiments injecting cryogenic impurity killer pellets of neon and argon and massive amounts of helium gas have successfully reduced these disruption effects. The halo current generation, scaling, and mitigation are understood and are in good agreement with predictions of a semianalytic model. Results from killer pellet injection have been used to benchmark theoretical models of the pellet ablation and energy loss. Runaway electrons are often generated by the pellets and new runaway generation mechanisms, modifications of the standard Dreicer process, have been found to explain the runaways. Experiments with the massive helium gas puff have also effectively mitigated disruptions without the formation of runaway electrons that can occur with killer pellets.

  14. The effects of resistance strategies on rape.

    PubMed Central

    Zoucha-Jensen, J M; Coyne, A

    1993-01-01

    This investigation sought to clarify which resistance strategies were associated with rape avoidance and at what cost. Data were gathered from initial and supplemental police reports about 150 sexual assault victims, ages 16 and older, who were assaulted between June 1, 1988, and May 31, 1989, in Omaha, Neb. Although this analysis could not determine causality, it did indicate that forceful verbal resistance, physical resistance, and fleeing were all associated with rape avoidance, whereas nonforceful verbal resistance and no resistance were associated with being raped. Further, women who used forceful resistance were no more likely to be injured than women who did not resist. PMID:8238695

  15. Crack Mitigation in Concrete: Superabsorbent Polymers as Key to Success?

    PubMed Central

    Mignon, Arn; Snoeck, Didier; Dubruel, Peter; Van Vlierberghe, Sandra; De Belie, Nele

    2017-01-01

    Cracking is a major concern in building applications. Cracks may arise from shrinkage, freeze/thawing and/or structural stresses, amongst others. Several solutions can be found but superabsorbent polymers (SAPs) seem to be interesting to counteract these problems. At an early age, the absorbed water by the SAPs may be used to mitigate autogenous and plastic shrinkage. The formed macro pores may increase the freeze/thaw resistance. The swelling upon water ingress may seal a crack from intruding fluids and may regain the overall water-tightness. The latter water may promote autogenous healing. The use of superabsorbent polymers is thus very interesting. This review paper summarizes the current research and gives a critical note towards the use of superabsorbent polymers in cementitious materials. PMID:28772599

  16. Crack Mitigation in Concrete: Superabsorbent Polymers as Key to Success?

    PubMed

    Mignon, Arn; Snoeck, Didier; Dubruel, Peter; Van Vlierberghe, Sandra; De Belie, Nele

    2017-02-28

    Cracking is a major concern in building applications. Cracks may arise from shrinkage, freeze/thawing and/or structural stresses, amongst others. Several solutions can be found but superabsorbent polymers (SAPs) seem to be interesting to counteract these problems. At an early age, the absorbed water by the SAPs may be used to mitigate autogenous and plastic shrinkage. The formed macro pores may increase the freeze/thaw resistance. The swelling upon water ingress may seal a crack from intruding fluids and may regain the overall water-tightness. The latter water may promote autogenous healing. The use of superabsorbent polymers is thus very interesting. This review paper summarizes the current research and gives a critical note towards the use of superabsorbent polymers in cementitious materials.

  17. The effect of rate of force development on maximal force production: acute and training-related aspects.

    PubMed

    Holtermann, Andreas; Roeleveld, Karin; Vereijken, Beatrix; Ettema, Gertjan

    2007-04-01

    The force generated during a maximal voluntary contraction (MVC) is known to increase by resistance training. Although this increase cannot be solely attributed to changes in the muscle itself, many studies examining muscle activation at peak force failed to detect neural adaptations with resistance training. However, the activation prior to peak force can have an impact on maximal force generation. This study aims at investigating the role of rate of force development (RFD) on maximal force during resistance training. Fourteen subjects carried out 5 days of isometric resistance training with dorsiflexion of the ankle with the instruction to generate maximal force. In a second experiment, 18 subjects performed the same task with the verbal instruction to generate maximal force (instruction I) and to generate force as fast and forcefully as possible (instruction II). The main findings were that RFD increased twice as much as the 16% increase in maximal force with training, with a positive association between RFD and force within the last session of training and between training sessions. Instruction II generated a higher RFD than instruction I, with no difference in maximal force. These findings suggest that the positive association between RFD and maximal force is not causal, but is mediated by a third factor. In the discussion, we argue for the third factor to be physiological changes affecting both aspects of a MVC or different processes affecting RFD and maximal force separately, rather than a voluntary strategic change of both aspects of MVC.

  18. Focused force angioplasty Theory and application

    SciTech Connect

    Solar, Ronald J.; Ischinger, Thomas A

    2003-03-01

    Focused force angioplasty is a technique in which the forces resulting from inflating an angioplasty balloon in a stenosis are concentrated and focused at one or more locations within the stenosis. While the technique has been shown to be useful in resolving resistant stenoses, its real value may be in minimizing the vascular trauma associated with balloon angioplasty and subsequently improving the outcome.

  19. Ray Effect Mitigation Through Reference Frame Rotation

    DOE PAGES

    Tencer, John

    2016-05-01

    The discrete ordinates method is a popular and versatile technique for solving the radiative transport equation, a major drawback of which is the presence of ray effects. Mitigation of ray effects can yield significantly more accurate results and enhanced numerical stability for combined mode codes. Moreover, when ray effects are present, the solution is seen to be highly dependent upon the relative orientation of the geometry and the global reference frame. It is an undesirable property. A novel ray effect mitigation technique of averaging the computed solution for various reference frame orientations is proposed.

  20. Ray Effect Mitigation Through Reference Frame Rotation

    SciTech Connect

    Tencer, John

    2016-05-01

    The discrete ordinates method is a popular and versatile technique for solving the radiative transport equation, a major drawback of which is the presence of ray effects. Mitigation of ray effects can yield significantly more accurate results and enhanced numerical stability for combined mode codes. Moreover, when ray effects are present, the solution is seen to be highly dependent upon the relative orientation of the geometry and the global reference frame. It is an undesirable property. A novel ray effect mitigation technique of averaging the computed solution for various reference frame orientations is proposed.