Science.gov

Sample records for activities pile driving

  1. Pile Driving

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Machine-oriented structural engineering firm TERA, Inc. is engaged in a project to evaluate the reliability of offshore pile driving prediction methods to eventually predict the best pile driving technique for each new offshore oil platform. Phase I Pile driving records of 48 offshore platforms including such information as blow counts, soil composition and pertinent construction details were digitized. In Phase II, pile driving records were statistically compared with current methods of prediction. Result was development of modular software, the CRIPS80 Software Design Analyzer System, that companies can use to evaluate other prediction procedures or other data bases.

  2. 76 FR 47155 - Takes of Marine Mammals Incidental to Specified Activities; Pile-Driving and Renovation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-04

    ...In accordance with the Marine Mammal Protection Act (MMPA) regulation, notification is hereby given that NMFS has issued an Incidental Harassment Authorization (IHA) to the Cher-Ae Heights Indian Community of the Trinidad Rancheria (Trinidad Rancheria) to take small numbers of marine mammals, by Level B harassment, incidental to pile- driving and renovation operations for the Trinidad Pier......

  3. 77 FR 43259 - Takes of Marine Mammals Incidental to Specified Activities; Pile Driving for Honolulu Seawater...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-24

    ...NMFS has received a complete and adequate application from Honolulu Seawater Air Conditioning, LLC (HSWAC) for an Incidental Harassment Authorization (IHA) to take marine mammals, by harassment, incidental to pile driving offshore Honolulu, Hawaii. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is proposing to issue an IHA to incidentally harass, by Level B harassment, 17 species of......

  4. 76 FR 51947 - Small Takes of Marine Mammals Incidental to Specified Activities; Pile Driving in the Columbia...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-19

    ... capacity. A pneumatic underwater chainsaw may be used if a pile breaks in the process, but associated noise... Port Townsend was used for the vibratory pile driving noise analysis (WSDOT, 2010b). There is a lack of... 1,016-mm) pile installations; therefore, noise levels recorded for projects in Alameda,...

  5. 77 FR 39471 - Small Takes of Marine Mammals Incidental to Specified Activities; Pile Driving in Port Townsend...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-03

    ...NMFS has received a complete and adequate application from the Washington State Department of Transportation/Ferries Division (WSF) for an Incidental Harassment Authorization (IHA) to take marine mammals, by harassment, incidental to pile driving during replacement of the Port Townsend Ferry Terminal Transfer Span. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS proposes to issue an......

  6. 77 FR 32943 - Takes of Marine Mammals Incidental to Specified Activities; Pile Driving in the Columbia River, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-04

    .... A pneumatic underwater chainsaw may be used if a pile breaks in the process, but associated noise is... notice in the Federal Register on August 19, 2011 (76 FR 51947), requesting comments from the public on... activity may be found in NMFS' proposed IHA document in the Federal Register (76 FR 51947, August 19,...

  7. 77 FR 59904 - Takes of Marine Mammals Incidental to Specified Activities; Pile Driving for Honolulu Seawater...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-01

    ... implementing regulations, NMFS issued a notice in the Federal Register on July 24, 2012 (77 FR 43259... description of the specified activity may be found in NMFS' proposed IHA notice in the Federal Register (77 FR... and Responses A proposed IHA and request for public comment was published on July 24, 2012 (77...

  8. Development of a geotechnical and pile driving database, Adriatic Sea

    SciTech Connect

    Carpaneto, R.; Paoletti, L.; Guaita, P.; Pratico, A.

    1996-12-31

    The paper presents a geotechnical and pile driving data base relevant to offshore installations in the Adriatic Sea. The paper discusses sources of information, structure, content, and engineering applications of the data base. Data available from Agip`s platform installations in the Adriatic was reviewed, and 20 representative platforms were chosen. Two relational data bases were created, for geotechnical and installation data respectively. The data bases provide a comprehensive and organized source of information about past experience in the area. Such experience is now quickly available for geotechnical engineering activities. As a main application of the data bases, information was processed to make data sets for training Artificial Neural Networks (ANN) to predict pile driveability. It is envisioned that the data bases will also be used in ongoing installation program design.

  9. 48. Photocopied August 1978. DRIVING PILES FOR THE POWER HOUSE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. Photocopied August 1978. DRIVING PILES FOR THE POWER HOUSE FOUNDATION, WEST END, AROUND SEPTEMBER 1, 1900. THE COFFER DAM HOLDING BACK THE ST. MARY'S IS AT THE LEFT. PILES SAWED TO LEVEL ARE ON THE LOWER RIGHT-HAND SIDE OF THE PHOTO. UNCUT PILES ARE AT THE CENTER. A SECOND PILE DRIVER WORKING FROM THE EAST END CAN BE SEEN IN THE BACKGROUND, ALONG WITH THE PUMPING PLANT AND THE STONE CRUSHING MACHINE. (71) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

  10. 48. EXCAVATING AND DRIVING PILES FOR SHOOFLY BRIDGE, YOLO COUNTY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. EXCAVATING AND DRIVING PILES FOR SHOOFLY BRIDGE, YOLO COUNTY SIDE OF RIVER, November 7, 1934 - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

  11. Analysis of Wave Fields induced by Offshore Pile Driving

    NASA Astrophysics Data System (ADS)

    Ruhnau, M.; Heitmann, K.; Lippert, T.; Lippert, S.; von Estorff, O.

    2015-12-01

    Impact pile driving is the common technique to install foundations for offshore wind turbines. With each hammer strike the steel pile - often exceeding 6 m in diameter and 80 m in length - radiates energy into the surrounding water and soil, until reaching its targeted penetration depth. Several European authorities introduced limitations regarding hydroacoustic emissions during the construction process to protect marine wildlife. Satisfying these regulations made the development and application of sound mitigation systems (e.g. bubble curtains or insulation screens) inevitable, which are commonly installed within the water column surrounding the pile or even the complete construction site. Last years' advances have led to a point, where the seismic energy tunneling the sound mitigation systems through the soil and radiating back towards the water column gains importance, as it confines the maximum achievable sound mitigation. From an engineering point of view, the challenge of deciding on an effective noise mitigation layout arises, which especially requires a good understanding of the soil-dependent wave field. From a geophysical point of view, the pile acts like a very unique line source, generating a characteristic wave field dominated by inclined wave fronts, diving as well as head waves. Monitoring the seismic arrivals while the pile penetration steadily increases enables to perform quasi-vertical seismic profiling. This work is based on datasets that have been collected within the frame of three comprehensive offshore measurement campaigns during pile driving and demonstrates the potential of seismic arrivals induced by pile driving for further soil characterization.

  12. Effects of Impulsive Pile-Driving Exposure on Fishes.

    PubMed

    Casper, Brandon M; Carlson, Thomas J; Halvorsen, Michele B; Popper, Arthur N

    2016-01-01

    Six species of fishes were tested under aquatic far-field, plane-wave acoustic conditions to answer several key questions regarding the effects of exposure to impulsive pile driving. The issues addressed included which sound levels lead to the onset of barotrauma injuries, how these levels differ between fishes with different types of swim bladders, the recovery from barotrauma injuries, and the potential effects exposure might have on the auditory system. The results demonstrate that the current interim criteria for pile-driving sound exposures are 20 dB or more below the actual sound levels that result in the onset of physiological effects on fishes. PMID:26610952

  13. 29 CFR 1926.603 - Pile driving equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Operations § 1926.603 Pile driving equipment. (a) General requirements. (1) Boilers and piping systems which... strength. (4) Stop blocks shall be provided for the leads to prevent the hammer from being raised against the head block. (5) A blocking device, capable of safely supporting the weight of the hammer, shall...

  14. 29 CFR 1926.603 - Pile driving equipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Operations § 1926.603 Pile driving equipment. (a) General requirements. (1) Boilers and piping systems which... strength. (4) Stop blocks shall be provided for the leads to prevent the hammer from being raised against the head block. (5) A blocking device, capable of safely supporting the weight of the hammer, shall...

  15. 29 CFR 1926.603 - Pile driving equipment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Operations § 1926.603 Pile driving equipment. (a) General requirements. (1) Boilers and piping systems which... strength. (4) Stop blocks shall be provided for the leads to prevent the hammer from being raised against the head block. (5) A blocking device, capable of safely supporting the weight of the hammer, shall...

  16. A computational model of pile vertical vibration in saturated soil based on the radial disturbed zone of pile driving

    NASA Astrophysics Data System (ADS)

    Li, Qiang; Shi, Qian; Wang, Kuihua

    2010-06-01

    In this study, a simplified computational model of pile vertical vibration was developed. The model was based on the inhomogeneous radial disturbed zone of soil in the vicinity of a pile disturbed by pile driving. The model contained two regions: the disturbed zone, which was located in the immediate vicinity of the pile, and the undisturbed region, external to the disturbed zone. In the model, excess pore pressure in the disturbed zone caused by pile driving was assumed to follow a logarithmic distribution. The relationships of stress and strain in the disturbed zone were based on the principle of effective stress under plain strain conditions. The external zone was governed by the poroelastic theory proposed by Biot. With the use of a variable separation method, an analytical solution in the frequency domain was obtained. Furthermore, a semi-analytical solution was attained by employing a numerical convolution method. Numerical results from the frequency and time domain indicated that the equivalent radius of the disturbed zone and the ratio of excess pore pressure had a significant effect on pile dynamic response. However, actual interactions between pile and soil will be weaker due to the presence of the radial disturbed zone, which is caused by pile driving. Consequently, the ideal undisturbed model overestimates the interaction between pile and soil; however, the proposed model reflects the interaction of pile and soil better than the perfect contact model. Numerical results indicate that the model can account for the time effect of pile dynamic tests.

  17. Noise Mitigation During Pile Driving Efficiently Reduces Disturbance of Marine Mammals.

    PubMed

    Nehls, Georg; Rose, Armin; Diederichs, Ansgar; Bellmann, Michael; Pehlke, Hendrik

    2016-01-01

    Acoustic monitoring of harbor porpoises (Phocoena phocoena L., 1758) indicated a strongly reduced disturbance by noise emitted by pile driving for offshore wind turbine foundations insulated by a big bubble curtain (BBC). This newly developed noise mitigation system was tested during construction of the offshore wind farm Borkum West II (North Sea). Because porpoise activity strongly corresponded to the sound level, operation of the new system under its most suitable configuration reduced the porpoise disturbance area by ~90%. Hence, for the first time, a positive effect of a noise mitigation system during offshore pile driving on an affected marine mammal species could be demonstrated. PMID:26611029

  18. The underwater sound field from vibratory pile driving.

    PubMed

    Dahl, Peter H; Dall'Osto, David R; Farrell, Dara M

    2015-06-01

    Underwater noise from vibratory pile driving was observed using a vertical line array placed at range 16 m from the pile source (water depth 7.5 m), and using single hydrophones at range 417 m on one transect, and range 207 and 436 m on another transect running approximately parallel to a sloping shoreline. The dominant spectral features of the underwater noise are related to the frequency of the vibratory pile driving hammer (typically 15-35 Hz), producing spectral lines at intervals of this frequency. The mean-square pressure versus depth is subsequently studied in third-octave bands. Depth and frequency variations of this quantity observed at the vertical line array are well modeled by a field consisting of an incoherent sum of sources distributed over the water column. Adiabatic mode theory is used to propagate this field to greater ranges and model the observations made along the two depth-varying transects. The effect of shear in the seabed, although small, is also included. Bathymetric refraction on the transect parallel to the shoreline reduced mean-square pressure levels at the 436-m measurement site. PMID:26093441

  19. Acoustic Response to Playback of Pile-Driving Sounds by Snapping Shrimp.

    PubMed

    Spiga, Ilaria

    2016-01-01

    There is concern about the effects of noise from impact pile driving as this constructional technique becomes increasingly widespread in coastal areas. The habitats of most marine invertebrate species are likely to overlap with the areas of human activities along the coast and be affected by the increased levels of noise produced. This paper investigates the acoustic response of chorusing snapping shrimp to different sound pressure levels. A significant increase in the snap number and snap amplitude was recorded during the playback of piling noise, suggesting that noise exposure affected the acoustic behavior of these animals. PMID:26611071

  20. Residency of Reef Fish During Pile Driving Within a Shallow Pierside Environment.

    PubMed

    Iafrate, Joseph D; Watwood, Stephanie L; Reyier, Eric A; Gilchrest, Matthew; Crocker, Steven E

    2016-01-01

    The potential effects of pile driving on fish populations and commercial fisheries have received significant attention given the prevalence of construction occurring in coastal habitats throughout the world. In this study, we used acoustic telemetry to assess the movement and survival of free-ranging reef fish in Port Canaveral, FL, in response to 35 days of pile driving at an existing wharf complex. The site fidelity and behavior of 15 sheepshead (Archosargus probatocephalus) and 10 gray snapper (Lutjanus griseus) were determined before, during, and after pile driving. No obvious signs of mortality or injury to tagged fish were evident from the data. There was a significant decline in the residency index for mangrove snapper at the construction wharf after pile driving compared with the baseline, although this may be influenced by natural movements of this species in the study area rather than a direct response to pile driving. PMID:26610995

  1. Acoustic stress responses in juvenile sea bass Dicentrarchus labrax induced by offshore pile driving.

    PubMed

    Debusschere, Elisabeth; Hostens, Kris; Adriaens, Dominique; Ampe, Bart; Botteldooren, Dick; De Boeck, Gudrun; De Muynck, Amelie; Sinha, Amit Kumar; Vandendriessche, Sofie; Van Hoorebeke, Luc; Vincx, Magda; Degraer, Steven

    2016-01-01

    Underwater sound generated by pile driving during construction of offshore wind farms is a major concern in many countries. This paper reports on the acoustic stress responses in young European sea bass Dicentrarchus labrax (68 and 115 days old), based on four in situ experiments as close as 45 m from a pile driving activity. As a primary stress response, whole-body cortisol seemed to be too sensitive to 'handling' bias. On the other hand, measured secondary stress responses to pile driving showed significant reductions in oxygen consumption rate and low whole-body lactate concentrations. Furthermore, repeated exposure to impulsive sound significantly affected both primary and secondary stress responses. Under laboratory conditions, no tertiary stress responses (no changes in specific growth rate or Fulton's condition factor) were noted in young sea bass 30 days after the treatment. Still, the demonstrated acute stress responses and potentially repeated exposure to impulsive sound in the field will inevitably lead to less fit fish in the wild. PMID:26561450

  2. Hearing thresholds of two harbor seals (Phoca vitulina) for playbacks of multiple pile driving strike sounds.

    PubMed

    Kastelein, Ronald A; Hoek, Lean; Gransier, Robin; Jennings, Nancy

    2013-09-01

    Pile driving, which creates high amplitude sounds with potentially negative impacts on the marine environment, is used to attach wind turbines to the sea bed. To quantify the distance at which pile driving sounds can be detected by harbor seals, unmasked hearing thresholds were obtained for series of five pile driving sounds recorded at 100 and 800 m from a pile driving location. The played back spectra resembled the spectra of sounds recorded under certain conditions 10-50 km from an offshore pile driving site. The lower the received level, the later within the series of sounds the harbor seals responded. The mean 50% detection threshold sound exposure levels for any sound in the series were: 40 (seal 01, 100 m), 39 (seal 01, 800 m), 43 (seal 02, 100 m), and 43 (seal 02, 800 m) dB re 1 μPa(2)s (add 9 dB for sound pressure level, dB re 1 μPa). The mean 50% detection thresholds based on detection of only the first sound of the series were ca. 5 dB higher. Detection at sea depends on the actual propagation conditions and on the degree of masking of the sounds by ambient noise, but the present study suggests that pile driving sounds are audible to harbor seals up to hundreds of kilometers from pile driving sites. PMID:23967961

  3. Methods for Predicting Potential Impacts of Pile-Driving Noise on Endangered Sturgeon During Bridge Construction.

    PubMed

    Krebs, Justin; Jacobs, Fred; Conway, Robert; Popper, Arthur N; Moese, Mark; Rollino, John; Racca, Roberto; Martin, Bruce; MacGillivray, Alexander

    2016-01-01

    The potential impacts of pile-driving noise on Hudson River sturgeon during construction of the New NY Bridge were predicted. Abundance data for shortnose and Atlantic sturgeon derived from fisheries sampling were combined with data about the spatial extent of pile-driving noise. This approach was used to calculate the number of sturgeon that could occur within sound level isopleths exceeding peak and cumulative noise criteria used by the National Marine Fisheries Service to determine the incidental take of sturgeon. The number of sturgeon subject to the potential onset of physiological effects during pile driving was predicted to be 35-41 fish for each species. PMID:26611005

  4. In Situ Mortality Experiments with Juvenile Sea Bass (Dicentrarchus labrax) in Relation to Impulsive Sound Levels Caused by Pile Driving of Windmill Foundations

    PubMed Central

    Debusschere, Elisabeth; De Coensel, Bert; Bajek, Aline; Botteldooren, Dick; Hostens, Kris; Vanaverbeke, Jan; Vandendriessche, Sofie; Van Ginderdeuren, Karl; Vincx, Magda; Degraer, Steven

    2014-01-01

    Impact assessments of offshore wind farm installations and operations on the marine fauna are performed in many countries. Yet, only limited quantitative data on the physiological impact of impulsive sounds on (juvenile) fishes during pile driving of offshore wind farm foundations are available. Our current knowledge on fish injury and mortality due to pile driving is mainly based on laboratory experiments, in which high-intensity pile driving sounds are generated inside acoustic chambers. To validate these lab results, an in situ field experiment was carried out on board of a pile driving vessel. Juvenile European sea bass (Dicentrarchus labrax) of 68 and 115 days post hatching were exposed to pile-driving sounds as close as 45 m from the actual pile driving activity. Fish were exposed to strikes with a sound exposure level between 181 and 188 dB re 1 µPa2.s. The number of strikes ranged from 1739 to 3067, resulting in a cumulative sound exposure level between 215 and 222 dB re 1 µPa2.s. Control treatments consisted of fish not exposed to pile driving sounds. No differences in immediate mortality were found between exposed and control fish groups. Also no differences were noted in the delayed mortality up to 14 days after exposure between both groups. Our in situ experiments largely confirm the mortality results of the lab experiments found in other studies. PMID:25275508

  5. In situ mortality experiments with juvenile sea bass (Dicentrarchus labrax) in relation to impulsive sound levels caused by pile driving of windmill foundations.

    PubMed

    Debusschere, Elisabeth; De Coensel, Bert; Bajek, Aline; Botteldooren, Dick; Hostens, Kris; Vanaverbeke, Jan; Vandendriessche, Sofie; Van Ginderdeuren, Karl; Vincx, Magda; Degraer, Steven

    2014-01-01

    Impact assessments of offshore wind farm installations and operations on the marine fauna are performed in many countries. Yet, only limited quantitative data on the physiological impact of impulsive sounds on (juvenile) fishes during pile driving of offshore wind farm foundations are available. Our current knowledge on fish injury and mortality due to pile driving is mainly based on laboratory experiments, in which high-intensity pile driving sounds are generated inside acoustic chambers. To validate these lab results, an in situ field experiment was carried out on board of a pile driving vessel. Juvenile European sea bass (Dicentrarchus labrax) of 68 and 115 days post hatching were exposed to pile-driving sounds as close as 45 m from the actual pile driving activity. Fish were exposed to strikes with a sound exposure level between 181 and 188 dB re 1 µPa².s. The number of strikes ranged from 1739 to 3067, resulting in a cumulative sound exposure level between 215 and 222 dB re 1 µPa².s. Control treatments consisted of fish not exposed to pile driving sounds. No differences in immediate mortality were found between exposed and control fish groups. Also no differences were noted in the delayed mortality up to 14 days after exposure between both groups. Our in situ experiments largely confirm the mortality results of the lab experiments found in other studies. PMID:25275508

  6. Hearing thresholds of a harbor porpoise (Phocoena phocoena) for playbacks of multiple pile driving strike sounds.

    PubMed

    Kastelein, Ronald A; Hoek, Lean; Gransier, Robin; de Jong, Christ A F

    2013-09-01

    Pile driving is presently the most common method used to attach wind turbines to the sea bed. To assess the impact of pile driving sounds on harbor porpoises, it is important to know at what distance these sounds can be detected. Using a psychophysical technique, a male porpoise's hearing thresholds were obtained for series of five pile driving sounds (inter-pulse interval 1.2-1.3 s) recorded at 100 and 800 m from the pile driving site, and played back in a pool. The 50% detection threshold sound exposure levels (SELs) for the first sound of the series (no masking) were 72 (100 m) and 74 (800 m) dB re 1 μPa(2)s. Multiple sounds in succession (series) caused a ~5 dB decrease in hearing threshold; the mean 50% detection threshold SELs for any sound in the series were 68 (100 m) and 69 (800 m) dB re 1 μPa(2)s. Depending on the actual propagation conditions and background noise levels, the results suggest that pile driving sounds are audible to porpoises at least at tens of kilometers from pile driving sites. PMID:23967960

  7. Behavioral responses of a harbor porpoise (Phocoena phocoena) to playbacks of broadband pile driving sounds.

    PubMed

    Kastelein, Ronald A; van Heerden, Dorianne; Gransier, Robin; Hoek, Lean

    2013-12-01

    The high under-water sound pressure levels (SPLs) produced during pile driving to build offshore wind turbines may affect harbor porpoises. To estimate the discomfort threshold of pile driving sounds, a porpoise in a quiet pool was exposed to playbacks (46 strikes/min) at five SPLs (6 dB steps: 130-154 dB re 1 μPa). The spectrum of the impulsive sound resembled the spectrum of pile driving sound at tens of kilometers from the pile driving location in shallow water such as that found in the North Sea. The animal's behavior during test and baseline periods was compared. At and above a received broadband SPL of 136 dB re 1 μPa [zero-peak sound pressure level: 151 dB re 1 μPa; t90: 126 ms; sound exposure level of a single strike (SELss): 127 dB re 1 μPa(2) s] the porpoise's respiration rate increased in response to the pile driving sounds. At higher levels, he also jumped out of the water more often. Wild porpoises are expected to move tens of kilometers away from offshore pile driving locations; response distances will vary with context, the sounds' source level, parameters influencing sound propagation, and background noise levels. PMID:24144856

  8. A three-dimensional vibroacoustic model for the prediction of underwater noise from offshore pile driving

    NASA Astrophysics Data System (ADS)

    Tsouvalas, A.; Metrikine, A. V.

    2014-04-01

    Steel monopiles are nowadays widely used as foundations for a large number of offshore structures. The installation procedure commonly involves a pile driving process which can last up to several hours depending upon pile dimensions, soil conditions and input energy of the hydraulic hammer. In impact pile driving, a hydraulic hammer delivers a series of hammer blows at the head of the pile that drive the pile into the sediment. Each hammer strike results in pile vibrations that emit strong impulsive sounds into the water column which can be harmful for the marine ecosystem. With today's increasing concern regarding the environmental impact of such operations, engineering tools which will be able to provide reliable predictions of the underwater noise levels are required. In this study, a linear semi-analytical formulation of the coupled vibroacoustics of a complete pile-water-soil interaction model is addressed. The pile is described by a high order thin shell theory whereas both water and soil are modelled as three-dimensional continua. Results obtained with the developed model indicate that the near-field response in the water column consists mainly of pressure conical waves generated by the supersonic compressional waves in the pile excited by the impact hammer. The soil response is dominated by shear waves with almost vertical polarization. The Scholte waves are also generated at the water-seabed interface which can produce pressure fluctuations in the water column that are particularly significant close to the sea floor. The effects of soil elasticity and pile size are thoroughly investigated and their influence on the generated pressure levels is highlighted. The results are also compared with those ones of a similar model in which the soil is treated as an equivalent acoustic fluid. It is shown that the latter approximation can yield inaccurate results at low frequencies especially for harder soil sediments.

  9. A computational method to predict and study underwater noise due to pile driving.

    PubMed

    Schecklman, Scott; Laws, Nathan; Zurk, Lisa M; Siderius, Martin

    2015-07-01

    A hybrid modeling approach that uses the parabolic equation (PE) with an empirical source model is presented to study and predict the underwater noise due to pile driving in shallow, inhomogeneous environments over long propagation ranges. The empirical source model uses a phased point source array to simulate the time-dependent pile source. The pile source is coupled with a broadband application of a PE wave propagation model that includes range dependent geoacoustic properties and bathymetry. Simulation results are shown to be in good agreement with several acoustic observations of pile driving in the Columbia River between Portland, OR and Vancouver, WA. The model is further applied to predict sound levels in the Columbia River and study the effects of variable bathymetry and sediment configurations on underwater sound levels. PMID:26233025

  10. Pile-Driving Pressure and Particle Velocity at the Seabed: Quantifying Effects on Crustaceans and Groundfish.

    PubMed

    Miller, James H; Potty, Gopu R; Kim, Hui-Kwan

    2016-01-01

    We modeled the effects of pile driving on crustaceans, groundfish, and other animals near the seafloor. Three different waves were investigated, including the compressional wave, shear wave, and interface wave. A finite element (FE) technique was employed in and around the pile, whereas a parabolic equation (PE) code was used to predict propagation at long ranges from the pile. Pressure, particle displacement, and particle velocity are presented as a function of range at the seafloor for a shallow-water environment near Rhode Island. We discuss the potential effects on animals near the seafloor. PMID:26611024

  11. Avoidance of Pile-Driving Noise by Hudson River Sturgeon During Construction of the New NY Bridge at Tappan Zee.

    PubMed

    Krebs, Justin; Jacobs, Fred; Popper, Arthur N

    2016-01-01

    Sturgeon movements were monitored during a pile-driving operation. Fewer sturgeon were detected during pile driving and remained for a shorter time than during silent control periods. Moreover, the short time spent by sturgeon near pile driving suggests that they were unlikely to have reached the criterion of 187 dB re 1 μPa(2)·s cumulative sound exposure level. These results suggest that sturgeon are likely to avoid impact pile driving and not remain long enough to experience physiological effects, thus providing empirical evidence that the 206 dB re 1 μPa peak sound pressure level is the appropriate criterion for assessing the impacts of pile-driving noise on sturgeon. PMID:26611004

  12. Pile Driving at the New Bridge at Tappan Zee: Potential Environmental Impacts.

    PubMed

    Popper, Arthur N; Moese, Mark; Rollino, John; Krebs, Justin; Racca, Roberto; Martin, Bruce; Zeddies, David; MacGillivray, Alexander; Jacobs, Fred

    2016-01-01

    A new bridge will be constructed to replace the aging Tappan Zee Bridge over the Hudson River in New York. Construction will potentially result in hydroacoustic impacts to the local fish fauna. As a consequence, a substantial environmental impact analysis had to be conducted to obtain construction permits. This paper describes the process of environmental analysis and some of the results of the studies that led up to the final permitting. The process included modeling of pile-driving acoustics, analysis of river ambient noise, analysis of test piling, and observations on fish behavior during these tests. PMID:26611043

  13. Recovery of Barotrauma Injuries in Chinook Salmon, Oncorhynchus tshawytscha from Exposure to Pile Driving Sound

    PubMed Central

    Casper, Brandon M.; Popper, Arthur N.; Matthews, Frazer; Carlson, Thomas J.; Halvorsen, Michele B.

    2012-01-01

    Juvenile Chinook salmon, Oncorhynchus tshawytscha, were exposed to simulated high intensity pile driving signals to evaluate their ability to recover from barotrauma injuries. Fish were exposed to one of two cumulative sound exposure levels for 960 pile strikes (217 or 210 dB re 1 µPa2·s SELcum; single strike sound exposure levels of 187 or 180 dB re 1 µPa2⋅s SELss respectively). This was followed by an immediate assessment of injuries, or assessment 2, 5, or 10 days post-exposure. There were no observed mortalities from the pile driving sound exposure. Fish exposed to 217 dB re 1 µPa2·s SELcum displayed evidence of healing from injuries as post-exposure time increased. Fish exposed to 210 dB re 1 µPa2·s SELcum sustained minimal injuries that were not significantly different from control fish at days 0, 2, and 10. The exposure to 210 dB re 1 µPa2·s SELcum replicated the findings in a previous study that defined this level as the threshold for onset of injury. Furthermore, these data support the hypothesis that one or two Mild injuries resulting from pile driving exposure are unlikely to affect the survival of the exposed animals, at least in a laboratory environment. PMID:22745794

  14. 77 FR 2701 - Takes of Marine Mammals Incidental to Specified Activities; Pile Placement for ORPC Maine's...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-19

    ... playbacks, ship and ice-breaking noise, vessel noise, acoustic harassment devices (AHDs), acoustic deterrent... install foundational piles to support an underwater tidal turbine unit. The turbine unit is approximately... driving activities after April 9 if they can demonstrate that noise levels caused by the impact hammer...

  15. Threshold for Onset of Injury in Chinook Salmon from Exposure to Impulsive Pile Driving Sounds

    PubMed Central

    Halvorsen, Michele B.; Casper, Brandon M.; Woodley, Christa M.; Carlson, Thomas J.; Popper, Arthur N.

    2012-01-01

    The risk of effects to fishes and other aquatic life from impulsive sound produced by activities such as pile driving and seismic exploration is increasing throughout the world, particularly with the increased exploitation of oceans for energy production. At the same time, there are few data that provide insight into the effects of these sounds on fishes. The goal of this study was to provide quantitative data to define the levels of impulsive sound that could result in the onset of barotrauma to fish. A High Intensity Controlled Impedance Fluid filled wave Tube was developed that enabled laboratory simulation of high-energy impulsive sound that were characteristic of aquatic far-field, plane-wave acoustic conditions. The sounds used were based upon the impulsive sounds generated by an impact hammer striking a steel shell pile. Neutrally buoyant juvenile Chinook salmon (Oncorhynchus tshawytscha) were exposed to impulsive sounds and subsequently evaluated for barotrauma injuries. Observed injuries ranged from mild hematomas at the lowest sound exposure levels to organ hemorrhage at the highest sound exposure levels. Frequency of observed injuries were used to compute a biological response weighted index (RWI) to evaluate the physiological impact of injuries at the different exposure levels. As single strike and cumulative sound exposure levels (SELss, SELcum respectively) increased, RWI values increased. Based on the results, tissue damage associated with adverse physiological costs occurred when the RWI was greater than 2. In terms of sound exposure levels a RWI of 2 was achieved for 1920 strikes by 177 dB re 1 µPa2⋅s SELss yielding a SELcum of 210 dB re 1 µPa2⋅s, and for 960 strikes by 180 dB re 1 µPa2⋅s SELss yielding a SELcum of 210 dB re 1 µPa2⋅s. These metrics define thresholds for onset of injury in juvenile Chinook salmon. PMID:22745695

  16. Effect of Pile-Driving Sounds on the Survival of Larval Fish.

    PubMed

    Bolle, Loes J; de Jong, Christ A F; Bierman, Stijn M; van Beek, Pieter J G; Wessels, Peter W; Blom, Ewout; van Damme, Cindy J G; Winter, Hendrik V; Dekeling, René P A

    2016-01-01

    Concern exists about the potential effects of pile-driving sounds on fish, but evidence is limited, especially for fish larvae. A device was developed to expose larvae to accurately reproduced pile-driving sounds. Controlled exposure experiments were carried out to examine the lethal effects in common sole larvae. No significant effects were observed at zero-to-peak pressure levels up to 210 dB re 1 μPa(2) and cumulative sound exposure levels up to 206 dB re 1 μPa(2)·s, which is well above the US interim criteria for nonauditory tissue damage in fish. Experiments are presently being carried out for European sea bass and herring larvae. PMID:26610948

  17. Common Sole Larvae Survive High Levels of Pile-Driving Sound in Controlled Exposure Experiments

    PubMed Central

    Bolle, Loes J.; de Jong, Christ A. F.; Bierman, Stijn M.; van Beek, Pieter J. G.; van Keeken, Olvin A.; Wessels, Peter W.; van Damme, Cindy J. G.; Winter, Hendrik V.; de Haan, Dick; Dekeling, René P. A.

    2012-01-01

    In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at which (sub-)lethal effects occur is limited for juvenile and adult fish, and virtually non-existent for fish eggs and larvae. A device was developed in which fish larvae can be exposed to underwater sound. It consists of a rigid-walled cylindrical chamber driven by an electro-dynamical sound projector. Samples of up to 100 larvae can be exposed simultaneously to a homogeneously distributed sound pressure and particle velocity field. Recorded pile-driving sounds could be reproduced accurately in the frequency range between 50 and 1000 Hz, at zero to peak pressure levels up to 210 dB re 1µPa2 (zero to peak pressures up to 32 kPa) and single pulse sound exposure levels up to 186 dB re 1µPa2s. The device was used to examine lethal effects of sound exposure in common sole (Solea solea) larvae. Different developmental stages were exposed to various levels and durations of pile-driving sound. The highest cumulative sound exposure level applied was 206 dB re 1µPa2s, which corresponds to 100 strikes at a distance of 100 m from a typical North Sea pile-driving site. The results showed no statistically significant differences in mortality between exposure and control groups at sound exposure levels which were well above the US interim criteria for non-auditory tissue damage in fish. Although our findings cannot be extrapolated to fish larvae in general, as interspecific differences in vulnerability to sound exposure may occur, they do indicate that previous assumptions and criteria may need to be revised. PMID:22431996

  18. Pile driving zone of responsiveness extends beyond 20 km for harbor porpoises (Phocoena phocoena (L.)).

    PubMed

    Tougaard, Jakob; Carstensen, Jacob; Teilmann, Jonas; Skov, Henrik; Rasmussen, Per

    2009-07-01

    Behavioral reactions of harbor porpoises (Phocoena phocoena) to underwater noise from pile driving were studied. Steel monopile foundations (4 m diameter) for offshore wind turbines were driven into hard sand in shallow water at Horns Reef, the North Sea. The impulsive sounds generated had high sound pressures [source level 235 dB re 1 microPa(pp) at 1 m, transmission loss 18 log(distance)] with a strong low frequency emphasis but with significant energy up to 100 kHz. Reactions of porpoises were studied by passive acoustic loggers (T-PODs). Intervals between echolocation events (encounters) were analyzed, and a significant increase was found from average 5.9 h between encounters in the construction period as a whole to on average 7.5 h between first and second encounters after pile driving. The size of the zone of responsiveness could not be inferred as no grading in response was observed with distance from the pile driving site but must have exceeded 21 km (distance to most distant T-POD station). PMID:19603857

  19. Threshold for onset of injury in Chinook salmon from exposure to impulsive pile driving sounds.

    PubMed

    Halvorsen, Michele B; Casper, Brandon M; Woodley, Christa M; Carlson, Thomas J; Popper, Arthur N

    2012-01-01

    The risk of effects to fishes and other aquatic life from impulsive sound produced by activities such as pile driving and seismic exploration is increasing throughout the world, particularly with the increased exploitation of oceans for energy production. At the same time, there are few data that provide insight into the effects of these sounds on fishes. The goal of this study was to provide quantitative data to define the levels of impulsive sound that could result in the onset of barotrauma to fish. A High Intensity Controlled Impedance Fluid filled wave Tube was developed that enabled laboratory simulation of high-energy impulsive sound that were characteristic of aquatic far-field, plane-wave acoustic conditions. The sounds used were based upon the impulsive sounds generated by an impact hammer striking a steel shell pile. Neutrally buoyant juvenile Chinook salmon (Oncorhynchus tshawytscha) were exposed to impulsive sounds and subsequently evaluated for barotrauma injuries. Observed injuries ranged from mild hematomas at the lowest sound exposure levels to organ hemorrhage at the highest sound exposure levels. Frequency of observed injuries were used to compute a biological response weighted index (RWI) to evaluate the physiological impact of injuries at the different exposure levels. As single strike and cumulative sound exposure levels (SEL(ss), SEL(cum) respectively) increased, RWI values increased. Based on the results, tissue damage associated with adverse physiological costs occurred when the RWI was greater than 2. In terms of sound exposure levels a RWI of 2 was achieved for 1920 strikes by 177 dB re 1 µPa(2)⋅s SEL(ss) yielding a SEL(cum) of 210 dB re 1 µPa(2)⋅s, and for 960 strikes by 180 dB re 1 µPa(2)⋅s SEL(ss) yielding a SEL(cum) of 210 dB re 1 µPa(2)⋅s. These metrics define thresholds for onset of injury in juvenile Chinook salmon. PMID:22745695

  20. A simple model to predict soil resistance to driving for long piles in deepwater normally consolidated clays

    SciTech Connect

    Dutt, R.N.; Doyle, E.H.; Collins, J.T.; Ganguly, P.

    1995-12-01

    As the exploration and development for offshore oil and gas reserves moves into the deepwater environment of the continental slope, a good model is necessary to evaluate drivability of large-diameter, long piles in normally consolidated clays. Procedures are available to predict soil resistance to driving in stiff to hard overconsolidated clays of the North Sea and the Arabian Gulf. Use of these procedures in normally consolidated clays grossly overpredicts soil resistance. Such gross overpredictions result in the mobilization of larger hammers or thicker pile wall than necessary for pile installation. A simple model is proposed to estimate soil resistance to driving. Case histories of recent deepwater pile installations are presented to illustrate the adequacy of the new procedure in deepwater normally consolidated clays.

  1. Effects of exposure to pile-driving sounds on the lake sturgeon, Nile tilapia and hogchoker

    PubMed Central

    Halvorsen, Michele B.; Casper, Brandon M.; Matthews, Frazer; Carlson, Thomas J.; Popper, Arthur N.

    2012-01-01

    Pile-driving and other impulsive sound sources have the potential to injure or kill fishes. One mechanism that produces injuries is the rapid motion of the walls of the swim bladder as it repeatedly contacts nearby tissues. To further understand the involvement of the swim bladder in tissue damage, a specially designed wave tube was used to expose three species to pile-driving sounds. Species included lake sturgeon (Acipenser fulvescens)—with an open (physostomous) swim bladder, Nile tilapia (Oreochromis niloticus)—with a closed (physoclistous) swim bladder and the hogchoker (Trinectes maculatus)—a flatfish without a swim bladder. There were no visible injuries in any of the exposed hogchokers, whereas a variety of injuries were observed in the lake sturgeon and Nile tilapia. At the loudest cumulative and single-strike sound exposure levels (SELcum and SELss respectively), the Nile tilapia had the highest total injuries and the most severe injuries per fish. As exposure levels decreased, the number and severity of injuries were more similar between the two species. These results suggest that the presence and type of swim bladder correlated with injury at higher sound levels, while the extent of injury at lower sound levels was similar for both kinds of swim bladders. PMID:23055066

  2. Effects of pile-driving on harbour porpoises (Phocoena phocoena) at the first offshore wind farm in Germany

    NASA Astrophysics Data System (ADS)

    Dähne, Michael; Gilles, Anita; Lucke, Klaus; Peschko, Verena; Adler, Sven; Krügel, Kathrin; Sundermeyer, Janne; Siebert, Ursula

    2013-06-01

    The first offshore wind farm ‘alpha ventus’ in the German North Sea was constructed north east of Borkum Reef Ground approximately 45 km north off the German coast in 2008 and 2009 using percussive piling for the foundations of 12 wind turbines. Visual monitoring of harbour porpoises was conducted prior to as well as during construction and operation by means of 15 aerial line transect distance sampling surveys, from 2008 to 2010. Static acoustic monitoring (SAM) with echolocation click loggers at 12 positions was performed additionally from 2008 to 2011. SAM devices were deployed between 1 and 50 km from the centre of the wind farm. During aerial surveys, 18 600 km of transect lines were covered in two survey areas (10 934 and 11 824 km2) and 1392 harbour porpoise sightings were recorded. Lowest densities were documented during the construction period in 2009. The spatial distribution pattern recorded on two aerial surveys three weeks before and exactly during pile-driving points towards a strong avoidance response within 20 km distance of the noise source. Generalized additive modelling of SAM data showed a negative impact of pile-driving on relative porpoise detection rates at eight positions at distances less than 10.8 km. Increased detection rates were found at two positions at 25 and 50 km distance suggesting that porpoises were displaced towards these positions. A pile-driving related behavioural reaction could thus be detected using SAM at a much larger distance than a pure avoidance radius would suggest. The first waiting time (interval between porpoise detections of at least 10 min), after piling started, increased with longer piling durations. A gradient in avoidance, a gradual fading of the avoidance reaction with increasing distance from the piling site, is hence most probably a product of an incomplete displacement during shorter piling events.

  3. Recovery of Barotrauma Injuries Resulting from Exposure to Pile Driving Sound in Two Sizes of Hybrid Striped Bass

    PubMed Central

    Matthews, Frazer; Carlson, Thomas J.; Popper, Arthur N.

    2013-01-01

    The effects of loud sounds on fishes, such as those produced during impulsive pile driving, are an increasing concern in the management of aquatic ecosystems. However, very little is known about such effects. Accordingly, a High Intensity Controlled Impedance Fluid Filled wave Tube (HICI-FT) was used to investigate the effects of sounds produced by impulsive pile driving on two size groups of hybrid striped bass (white bass Moronechrysops x striped bass Moronesaxatilis). The larger striped bass (mean size 17.2 g) had more severe injuries, as well as more total injuries, than the smaller fish (mean size 1.3 g). However, fish in each size group recovered from most injuries within 10 days of exposure. A comparison with different species from previously published studies show that current results support the observation that fishes with physoclistous swim bladders are more susceptible to injury from impulsive pile driving than are fishes with physostomous swim bladders. PMID:24040089

  4. Big Pile or Small Pile?

    ERIC Educational Resources Information Center

    Branca, Mario; Quidacciolu, Rossana G.; Soletta, Isabella

    2013-01-01

    The construction of a voltaic pile (battery) is a simple laboratory activity that commemorates the invention of this important device and is of great help in teaching physics. The voltaic pile is often seen as a scientific toy, with the "pile" being constructed from fruit. These toys use some strips of copper and zinc inserted in a piece…

  5. Pile driving models for the evaluation of soil penetration resistance measurements from planetary subsurface probes

    NASA Astrophysics Data System (ADS)

    Kömle, Norbert I.; Poganski, Joshua; Kargl, Günter; Grygorczuk, Jerzy

    2015-05-01

    Several planetary lander missions conducted in the past and planned for the near future have instruments on board, which are dedicated to the determination of various material properties, among them mechanical properties of the surface like material strength and penetration resistance. In this paper two instruments are considered in more detail: (i) the MUPUS penetrator, a device aboard the Lander Philae of ESA's Rosetta mission, and (ii) the Mole HP3, which is part of the payload of NASA's next Discovery mission InSight, due for landing on Mars in 2016. Both devices are driven by hammering mechanisms designed to work under low or micro-gravity conditions and blaze themselves a trail into the subsurface of their respective target bodies. Naturally the speed with which this process takes place and if penetration is possible at all depends on the mechanical properties of the soil. However, a quantitative evaluation of soil mechanical parameters from measured depth-versus-time data is not a straightforward task. In this paper we apply an old technique, originally developed for modelling the driving of a pile into the ground, to describe the performance of penetrators and Moles developed for planetary applications. The numerical pile driving model of Smith (1962) is scaled and adapted for this purpose and used to predict the penetration behaviour of these instruments in dependence of their internal construction and the properties of the soil they are driven in. The model computes the permanent set of the surrounding soil in response to one hammer blow cycle as well as the oscillations and waves excited inside the devices and in the surrounding soil. Both the penetration resistance of the tip and the resistance caused by friction of the penetrator along the cylindrical side wall are calculated. By comparing the modelling results with previous laboratory measurements it is demonstrated that the models produce realistic results and can be used both as tools for proper

  6. The significance of parameter uncertainties for the prediction of offshore pile driving noise.

    PubMed

    Lippert, Tristan; von Estorff, Otto

    2014-11-01

    Due to the construction of offshore wind farms and its potential effect on marine wildlife, the numerical prediction of pile driving noise over long ranges has recently gained importance. In this contribution, a coupled finite element/wavenumber integration model for noise prediction is presented and validated by measurements. The ocean environment, especially the sea bottom, can only be characterized with limited accuracy in terms of input parameters for the numerical model at hand. Therefore the effect of these parameter uncertainties on the prediction of sound pressure levels (SPLs) in the water column is investigated by a probabilistic approach. In fact, a variation of the bottom material parameters by means of Monte-Carlo simulations shows significant effects on the predicted SPLs. A sensitivity analysis of the model with respect to the single quantities is performed, as well as a global variation. Based on the latter, the probability distribution of the SPLs at an exemplary receiver position is evaluated and compared to measurements. The aim of this procedure is to develop a model to reliably predict an interval for the SPLs, by quantifying the degree of uncertainty of the SPLs with the MC simulations. PMID:25373948

  7. Hearing frequency thresholds of harbor porpoises (Phocoena phocoena) temporarily affected by played back offshore pile driving sounds.

    PubMed

    Kastelein, Ronald A; Gransier, Robin; Marijt, Michelle A T; Hoek, Lean

    2015-02-01

    Harbor porpoises may suffer hearing loss when exposed to intense sounds. After exposure to playbacks of broadband pile driving sounds for 60 min, the temporary hearing threshold shift (TTS) of a porpoise was quantified at 0.5, 1, 2, 4, 8, 16, 32, 63, and 125 kHz with a psychoacoustic technique. Details of the pile driving sounds were as follows: pulse duration 124 ms, rate 2760 strikes/h, inter-pulse interval 1.3 s, average received single strike unweighted sound exposure level (SEL) 146 dB re 1 μPa(2) s (cumulative SEL: 180 dB re 1 μPa(2) s). Statistically significant TTS only occurred at 4 and 8 kHz; mean TTS (1-4 min. after sound exposure stopped) was 2.3 dB at 4 kHz, and 3.6 dB at 8 kHz; recovery occurred within 48 min. This study shows that exposure to multiple impulsive sounds with most of their energy in the low frequencies can cause reduced hearing at higher frequencies in harbor porpoises. The porpoise's hearing threshold for the frequency in the range of its echolocation signals was not affected by the pile driving playback sounds. PMID:25697990

  8. Assessing underwater noise levels during pile-driving at an offshore windfarm and its potential effects on marine mammals.

    PubMed

    Bailey, Helen; Senior, Bridget; Simmons, Dave; Rusin, Jan; Picken, Gordon; Thompson, Paul M

    2010-06-01

    Marine renewable developments have raised concerns over impacts of underwater noise on marine species, particularly from pile-driving for wind turbines. Environmental assessments typically use generic sound propagation models, but empirical tests of these models are lacking. In 2006, two 5MW wind turbines were installed off NE Scotland. The turbines were in deep (>40m) water, 25km from the Moray Firth Special Area of Conservation (SAC), potentially affecting a protected population of bottlenose dolphins. We measured pile-driving noise at distances of 0.1 (maximum broadband peak to peak sound level 205dB re 1microPa) to 80km (no longer distinguishable above background noise). These sound levels were related to noise exposure criteria for marine mammals to assess possible effects. For bottlenose dolphins, auditory injury would only have occurred within 100m of the pile-driving and behavioural disturbance, defined as modifications in behaviour, could have occurred up to 50km away. PMID:20152995

  9. Noise reduction by the application of an air-bubble curtain in offshore pile driving

    NASA Astrophysics Data System (ADS)

    Tsouvalas, A.; Metrikine, A. V.

    2016-06-01

    Underwater noise pollution is a by-product of marine industrial operations. In particular, the noise generated when a foundation pile is driven into the soil with an impact hammer is considered to be harmful for the aquatic species. In an attempt to reduce the ecological footprint, several noise mitigation techniques have been investigated. Among the various solutions proposed, the air-bubble curtain is often applied due to its efficacy in noise reduction. In this paper, a model is proposed for the investigation of the sound reduction during marine piling when an air-bubble curtain is placed around the pile. The model consists of the pile, the surrounding water and soil media, and the air-bubble curtain which is positioned at a certain distance from the pile surface. The solution approach is semi-analytical and is based on the dynamic sub-structuring technique and the modal decomposition method. Two main results of the paper can be distinguished. First, a new model is proposed that can be used for predictions of the noise levels in a computationally efficient manner. Second, an analysis is presented of the principal mechanisms that are responsible for the noise reduction due to the application of the air-bubble curtain in marine piling. The understanding of these mechanisms turns to be crucial for the exploitation of the maximum efficiency of the system. It is shown that the principal mechanism of noise reduction depends strongly on the frequency content of the radiated sound and the characteristics of the bubbly medium. For piles of large diameter which radiate most of the acoustic energy at relatively low frequencies, the noise reduction is mainly attributed to the mismatch of the acoustic impedances between the seawater and the bubbly layer. On the contrary, for smaller piles and when the radiated acoustic energy is concentrated at frequencies close to, or higher than, the resonance frequency of the air bubbles, the sound absorption within the bubbly layer

  10. Empirical estimation of peak pressure level from sound exposure level. Part II: Offshore impact pile driving noise.

    PubMed

    Lippert, Tristan; Galindo-Romero, Marta; Gavrilov, Alexander N; von Estorff, Otto

    2015-09-01

    Numerical models of underwater sound propagation predict the energy of impulsive signals and its decay with range with a better accuracy than the peak pressure. A semi-empirical formula is suggested to predict the peak pressure of man-made impulsive signals based on numerical predictions of their energy. The approach discussed by Galindo-Romero, Lippert, and Gavrilov [J. Acoust. Soc. Am. 138, in press (2015)] for airgun signals is modified to predict the peak pressure from offshore pile driving, which accounts for impact and pile parameters. It is shown that using the modified empirical formula provides more accurate predictions of the peak pressure than direct numerical simulations of the signal waveform. PMID:26428828

  11. Pile driving playback sounds and temporary threshold shift in harbor porpoises (Phocoena phocoena): Effect of exposure duration.

    PubMed

    Kastelein, Ronald A; Helder-Hoek, Lean; Covi, Jennifer; Gransier, Robin

    2016-05-01

    High intensity underwater sounds may cause temporary hearing threshold shifts (TTSs) in harbor porpoises, the magnitude of which may depend on the exposure duration. After exposure to playbacks of pile driving sounds, TTSs in two porpoises were quantified at 4 and 8 kHz with a psychophysical technique. At 8 kHz, the pile driving sounds caused the highest TTS. Pile driving sounds had the following: pulse duration 124 ms, rate 2760 strikes/h, inter-pulse interval 1.3 s, duty cycle ∼9.5%, average received single-strike unweighted broadband sound exposure level (SELss) 145 dB re 1 μPa(2)s, exposure duration range 15-360 min (cumulative SEL range: 173-187 dB re 1 μPa(2)s). Control sessions were also carried out. Mean TTS (1-4 min after sound exposure stopped in one porpoise, and 12-16 min in the other animal) increased from 0 dB after 15 min exposure to 5 dB after 360 min exposure. Recovery occurred within 60 min post-exposure. For the signal duration, sound pressure level (SPL), and duty cycle used, the TTS onset SELcum is estimated to be around 175 dB re 1 μPa(2)s. The small increase in TTS between 15 and 360 min exposures is due to the small amount of sound energy per unit of time to which the porpoises were exposed [average (over time) broadband SPL ∼144 dB re 1 μPa]. PMID:27250176

  12. Validation of finite element computations for the quantitative prediction of underwater noise from impact pile driving.

    PubMed

    Zampolli, Mario; Nijhof, Marten J J; de Jong, Christ A F; Ainslie, Michael A; Jansen, Erwin H W; Quesson, Benoit A J

    2013-01-01

    The acoustic radiation from a pile being driven into the sediment by a sequence of hammer strikes is studied with a linear, axisymmetric, structural acoustic frequency domain finite element model. Each hammer strike results in an impulsive sound that is emitted from the pile and then propagated in the shallow water waveguide. Measurements from accelerometers mounted on the head of a test pile and from hydrophones deployed in the water are used to validate the model results. Transfer functions between the force input at the top of the anvil and field quantities, such as acceleration components in the structure or pressure in the fluid, are computed with the model. These transfer functions are validated using accelerometer or hydrophone measurements to infer the structural forcing. A modeled hammer forcing pulse is used in the successive step to produce quantitative predictions of sound exposure at the hydrophones. The comparison between the model and the measurements shows that, although several simplifying assumptions were made, useful predictions of noise levels based on linear structural acoustic models are possible. In the final part of the paper, the model is used to characterize the pile as an acoustic radiator by analyzing the flow of acoustic energy. PMID:23297884

  13. ACTIV: Sandwich Detector Activity from In-Pile Slowing-Down Spectra Experiment

    2013-08-01

    ACTIV calculates the activities of a sandwich detector, to be used for in-pile measurements in slowing-down spectra below a few keV. The effect of scattering with energy degradation in the filter and in the detectors has been included to a first approximation.

  14. Big Pile or Small Pile?

    NASA Astrophysics Data System (ADS)

    Branca, Mario; Quidacciolu, Rossana G.; Soletta, Isabella

    2013-10-01

    The construction of a voltaic pile (battery) is a simple laboratory activity that commemorates the invention of this important device and is of great help in teaching physics. The voltaic pile is often seen as a scientific toy, with the "pile" being constructed from fruit. These toys use some strips of copper and zinc inserted in a piece of fruit to produce a low-intensity electrical current to power a digital device. In a voltaic pile of this type, the zinc acts as an anode while the copper acts as a cathode. The reduction reaction [i.e.,2H+(aq)+2e⇋H2(g)] occurs on the copper (the cathode). The two electrons that are needed for the reduction are taken from the metal (copper), which remains positively charged, while the anode is the zinc, which is oxidized through the reaction Zn∘(m)⇋Zn+2(aq )+2e, and the two electrons remain on the metal, which is negatively charged. If the two pieces of metal are connected by an external conductor, electrons flow from the zinc to the copper. The electromotive force of this system is about 0.76 V, which is the reduction potential of zinc, as can be found in the table of standard reduction potentials.

  15. Framework for assessing impacts of pile-driving noise from offshore wind farm construction on a harbour seal population

    SciTech Connect

    Thompson, Paul M.; Hastie, Gordon D.; Nedwell, Jeremy; Barham, Richard; Brookes, Kate L.; Cordes, Line S.; Bailey, Helen; McLean, Nancy

    2013-11-15

    Offshore wind farm developments may impact protected marine mammal populations, requiring appropriate assessment under the EU Habitats Directive. We describe a framework developed to assess population level impacts of disturbance from piling noise on a protected harbour seal population in the vicinity of proposed wind farm developments in NE Scotland. Spatial patterns of seal distribution and received noise levels are integrated with available data on the potential impacts of noise to predict how many individuals are displaced or experience auditory injury. Expert judgement is used to link these impacts to changes in vital rates and applied to population models that compare population changes under baseline and construction scenarios over a 25 year period. We use published data and hypothetical piling scenarios to illustrate how the assessment framework has been used to support environmental assessments, explore the sensitivity of the framework to key assumptions, and discuss its potential application to other populations of marine mammals. -- Highlights: • We develop a framework to support Appropriate Assessment for harbour seal populations. • We assessed potential impacts of wind farm construction noise. • Data on distribution of seals and noise were used to predict effects on individuals. • Expert judgement linked these impacts to vital rates to model population change. • We explore the sensitivity of the framework to key assumptions and uncertainties.

  16. 75 FR 48941 - Takes of Marine Mammals Incidental to Specified Activities; Piling and Structure Removal in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-12

    ... relocated from removed pilings to pilings that are retained for seal habitat and buffer, using a small boat... the seal haul-out so that there is an opportunity for the seals to adjust to the presence of the... expected to result in harbor seal harassment. Approximately 25 purple martin nest boxes would be...

  17. Recurrent network activity drives striatal synaptogenesis.

    PubMed

    Kozorovitskiy, Yevgenia; Saunders, Arpiar; Johnson, Caroline A; Lowell, Bradford B; Sabatini, Bernardo L

    2012-05-31

    Neural activity during development critically shapes postnatal wiring of the mammalian brain. This is best illustrated by the sensory systems, in which the patterned feed-forward excitation provided by sensory organs and experience drives the formation of mature topographic circuits capable of extracting specific features of sensory stimuli. In contrast, little is known about the role of early activity in the development of the basal ganglia, a phylogenetically ancient group of nuclei fundamentally important for complex motor action and reward-based learning. These nuclei lack direct sensory input and are only loosely topographically organized, forming interlocking feed-forward and feed-back inhibitory circuits without laminar structure. Here we use transgenic mice and viral gene transfer methods to modulate neurotransmitter release and neuronal activity in vivo in the developing striatum. We find that the balance of activity between the two inhibitory and antagonist pathways in the striatum regulates excitatory innervation of the basal ganglia during development. These effects indicate that the propagation of activity through a multi-stage network regulates the wiring of the basal ganglia, revealing an important role of positive feedback in driving network maturation. PMID:22660328

  18. 77 FR 15045 - Takes of Marine Mammals Incidental to Specified Activities; Pile Placement for ORPC Maine's...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-14

    ... FR 2701, January 19, 2012). Negligible Impact and Small Numbers Analysis and Determination NMFS has...), allowing the take of small numbers of marine mammals, by Level B harassment only, incidental to pile... request, the incidental, but not intentional, taking of small numbers of marine mammals by U.S....

  19. 76 FR 28733 - Takes of Marine Mammals Incidental to Specified Activities; Pile-Driving and Renovation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-18

    ... Harassment Authorization (IHA) to take small numbers of marine mammals, by Level B harassment, incidental to... is provided to the public for review. An authorization to take small numbers of marine mammals by... an authorization to incidentally take small numbers of marine mammals by harassment. Except...

  20. 46. Photocopied August 1978. PILE DRIVERS #1 and #2, HOUSED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. Photocopied August 1978. PILE DRIVERS #1 and #2, HOUSED FOR WINTER WORK, AT COMPLETION OF PILE DRIVING FOR COFFER DAM OF POWER HOUSE, APRIL 1, 1899. SOME OF THE TRIPLE -LAP SHEET PILES USED IN THE DAM ARE SHOWN IN THE FOREGROUND. (29) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

  1. Eye movements and hazard perception in active and passive driving

    PubMed Central

    Mackenzie, Andrew K.; Harris, Julie M.

    2015-01-01

    ABSTRACT Differences in eye movement patterns are often found when comparing passive viewing paradigms to actively engaging in everyday tasks. Arguably, investigations into visuomotor control should therefore be most useful when conducted in settings that incorporate the intrinsic link between vision and action. We present a study that compares oculomotor behaviour and hazard reaction times across a simulated driving task and a comparable, but passive, video-based hazard perception task. We found that participants scanned the road less during the active driving task and fixated closer to the front of the vehicle. Participants were also slower to detect the hazards in the driving task. Our results suggest that the interactivity of simulated driving places increased demand upon the visual and attention systems than simply viewing driving movies. We offer insights into why these differences occur and explore the possible implications of such findings within the wider context of driver training and assessment. PMID:26681913

  2. Cerebral oscillatory activity during simulated driving using MEG

    PubMed Central

    Sakihara, Kotoe; Hirata, Masayuki; Ebe, Kazutoshi; Kimura, Kenji; Yi Ryu, Seong; Kono, Yoshiyuki; Muto, Nozomi; Yoshioka, Masako; Yoshimine, Toshiki; Yorifuji, Shiro

    2014-01-01

    We aimed to examine cerebral oscillatory differences associated with psychological processes during simulated car driving. We recorded neuromagnetic signals in 14 healthy volunteers using magnetoencephalography (MEG) during simulated driving. MEG data were analyzed using synthetic aperture magnetometry to detect the spatial distribution of cerebral oscillations. Group effects between subjects were analyzed statistically using a non-parametric permutation test. Oscillatory differences were calculated by comparison between “passive viewing” and “active driving.” “Passive viewing” was the baseline, and oscillatory differences during “active driving” showed an increase or decrease in comparison with a baseline. Power increase in the theta band was detected in the superior frontal gyrus (SFG) during active driving. Power decreases in the alpha, beta, and low gamma bands were detected in the right inferior parietal lobe (IPL), left postcentral gyrus (PoCG), middle temporal gyrus (MTG), and posterior cingulate gyrus (PCiG) during active driving. Power increase in the theta band in the SFG may play a role in attention. Power decrease in the right IPL may reflect selectively divided attention and visuospatial processing, whereas that in the left PoCG reflects sensorimotor activation related to driving manipulation. Power decreases in the MTG and PCiG may be associated with object recognition. PMID:25566017

  3. Neurobiology driving hyperactivity in activity-based anorexia.

    PubMed

    Adan, R A H; Hillebrand, J J G; Danner, U N; Cardona Cano, S; Kas, M J H; Verhagen, L A W

    2011-01-01

    Hyperactivity in anorexia nervosa is difficult to control and negatively impacts outcome. Hyperactivity is a key driving force to starvation in an animal model named activity-based anorexia (ABA). Recent research has started unraveling what mechanisms underlie this hyperactivity. Besides a general increase in locomotor activity that may be an expression of foraging behavior and involves frontal brain regions, the increased locomotor activity expressed before food is presented (food anticipatory behavior or FAA) involves hypothalamic neural circuits. Ghrelin plays a role in FAA, whereas decreased leptin signaling is involved in both aspects of increased locomotor activity. We hypothesize that increased ghrelin and decreased leptin signaling drive the activity of dopamine neurons in the ventral tegmental area. In anorexia nervosa patients, this altered activity of the dopamine system may be involved not only in hyperactivity but also in aberrant cognitive processing related to food. PMID:21243479

  4. 77 FR 14736 - Takes of Marine Mammals Incidental to Specified Activities; Pile Placement for Fishermen's...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-13

    ..., Beaufort sea state, cloud cover, and visibility). In the unanticipated event that the specified activity...; Water depth; Environmental conditions (e.g., wind speed and direction, Beaufort sea state, cloud...

  5. 77 FR 39999 - Takes of Marine Mammals Incidental to Specified Activities; Pile Placement for Fishermen's...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-06

    ..., NMFS issued a notice in the Federal Register on March 13, 2012 (77 FR 14736), requesting comments from... specified activity may be found in NMFS' proposed IHA notice in the Federal Register (77 FR 14736, March 13... FR 14736). During the 30-day public comment period, the Marine Mammal Commission...

  6. 76 FR 67419 - Takes of Marine Mammals Incidental to Specified Activities; Piling and Structure Removal in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-01

    ..., 2010, through February 28, 2011 (75 FR 67951). The specified activity includes all or part of the... (76 FR 56172). A complete description of the action was included in that notice and will not be... September 12, 2011, NMFS published a notice of proposed IHA (76 FR 56172) in response to DNR's request...

  7. 76 FR 56172 - Takes of Marine Mammals Incidental to Specified Activities; Piling and Structure Removal in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-12

    ... February 28, 2011 (75 FR 67951). The specified activity includes all or part of the following actions... remnant log boom structures have been utilized as haul-out habitat for resting, pupping and molting for... Pier in the main operational area of the log dump, is composed of 6 log boom rows and 1...

  8. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Coal mine waste: Refuse piles. 816.83 Section... ACTIVITIES § 816.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 816.81, the...) Drainage control. (1) If the disposal area contains springs, natural or manmade water courses, or...

  9. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Coal mine waste: Refuse piles. 817.83 Section... ACTIVITIES § 817.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 817.81, the...) Drainage control. (1) If the disposal area contains springs, natural or manmade water courses, or...

  10. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Coal mine waste: Refuse piles. 817.83 Section... ACTIVITIES § 817.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 817.81, the...) Drainage control. (1) If the disposal area contains springs, natural or manmade water courses, or...

  11. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Coal mine waste: Refuse piles. 817.83 Section... ACTIVITIES § 817.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 817.81, the...) Drainage control. (1) If the disposal area contains springs, natural or manmade water courses, or...

  12. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Coal mine waste: Refuse piles. 816.83 Section... ACTIVITIES § 816.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 816.81, the...) Drainage control. (1) If the disposal area contains springs, natural or manmade water courses, or...

  13. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Coal mine waste: Refuse piles. 816.83 Section... ACTIVITIES § 816.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 816.81, the...) Drainage control. (1) If the disposal area contains springs, natural or manmade water courses, or...

  14. 45. Photocopied August 1978. PILE DRIVER, NOVEMBER 2, 1898. THIS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. Photocopied August 1978. PILE DRIVER, NOVEMBER 2, 1898. THIS MACHINE WAS USED TO DRIVE PILES FOR THE POWER HOUSE COFFER DAM. AT THIS POINT IT IS JUST BEGINNING WORK. (12) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

  15. Prefrontal parvalbumin interneurons shape neuronal activity to drive fear expression.

    PubMed

    Courtin, Julien; Chaudun, Fabrice; Rozeske, Robert R; Karalis, Nikolaos; Gonzalez-Campo, Cecilia; Wurtz, Hélène; Abdi, Azzedine; Baufreton, Jerome; Bienvenu, Thomas C M; Herry, Cyril

    2014-01-01

    Synchronization of spiking activity in neuronal networks is a fundamental process that enables the precise transmission of information to drive behavioural responses. In cortical areas, synchronization of principal-neuron spiking activity is an effective mechanism for information coding that is regulated by GABA (γ-aminobutyric acid)-ergic interneurons through the generation of neuronal oscillations. Although neuronal synchrony has been demonstrated to be crucial for sensory, motor and cognitive processing, it has not been investigated at the level of defined circuits involved in the control of emotional behaviour. Converging evidence indicates that fear behaviour is regulated by the dorsomedial prefrontal cortex (dmPFC). This control over fear behaviour relies on the activation of specific prefrontal projections to the basolateral complex of the amygdala (BLA), a structure that encodes associative fear memories. However, it remains to be established how the precise temporal control of fear behaviour is achieved at the level of prefrontal circuits. Here we use single-unit recordings and optogenetic manipulations in behaving mice to show that fear expression is causally related to the phasic inhibition of prefrontal parvalbumin interneurons (PVINs). Inhibition of PVIN activity disinhibits prefrontal projection neurons and synchronizes their firing by resetting local theta oscillations, leading to fear expression. Our results identify two complementary neuronal mechanisms mediated by PVINs that precisely coordinate and enhance the neuronal activity of prefrontal projection neurons to drive fear expression. PMID:24256726

  16. 77 FR 69797 - Small Takes of Marine Mammals Incidental to Specified Activities; Pile Driving in Port Townsend...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-21

    ... propagation and sound sources were provided in the Federal Register notice (77 FR 39471, July 3, 2012... Register on July 3, 2012 (77 FR 39471). During the 30-day comment period, NMFS received a letter from the..., minke whale, Pacific harbor seal, California sea lion, northern elephant seal, and Steller sea lion....

  17. A Pile of Legos.

    ERIC Educational Resources Information Center

    DePino, Andrew, Jr.

    1994-01-01

    Describes the relationships a high school built with neighborhood industry, a national laboratory, a national museum, and a large university while trying to build a scale model of the original atomic pile. Provides suggestions for teachers. (MVL)

  18. MOMENTUM DRIVING: WHICH PHYSICAL PROCESSES DOMINATE ACTIVE GALACTIC NUCLEUS FEEDBACK?

    SciTech Connect

    Ostriker, Jeremiah P.; Choi, Ena; Novak, Gregory S.; Ciotti, Luca; Proga, Daniel

    2010-10-10

    The deposition of mechanical feedback from a supermassive black hole (SMBH) in an active galactic nucleus into the surrounding galaxy occurs via broad-line winds which must carry mass and radial momentum as well as energy. The effect can be summarized by the dimensionless parameter {eta}= M-dot{sub outf}/ M-dot{sub acc}=2{epsilon}{sub w}c{sup 2}/v{sub w}{sup 2} where {epsilon}{sub w} ({identical_to} E-dot{sub w}/(M-dot{sub acc}c{sup 2})) is the efficiency with which accreted matter is turned into wind energy in the disk surrounding the central SMBH. The outflowing mass and momentum are proportional to {eta}, and many prior treatments have essentially assumed that {eta} = 0. We perform one- and two-dimensional simulations and find that the growth of the central SMBH is very sensitive to the inclusion of the mass and momentum driving but is insensitive to the assumed mechanical efficiency. For example in representative calculations, the omission of momentum and mass feedback leads to a hundred-fold increase in the mass of the SMBH to over 10{sup 10} M{sub sun}. When allowance is made for momentum driving, the final SMBH mass is much lower and the wind efficiencies that lead to the most observationally acceptable results are relatively low with {epsilon}{sub w} {approx}< 10{sup -4}.

  19. Spontaneous Activity Drives Local Synaptic Plasticity In Vivo.

    PubMed

    Winnubst, Johan; Cheyne, Juliette E; Niculescu, Dragos; Lohmann, Christian

    2015-07-15

    Spontaneous activity fine-tunes neuronal connections in the developing brain. To explore the underlying synaptic plasticity mechanisms, we monitored naturally occurring changes in spontaneous activity at individual synapses with whole-cell patch-clamp recordings and simultaneous calcium imaging in the mouse visual cortex in vivo. Analyzing activity changes across large populations of synapses revealed a simple and efficient local plasticity rule: synapses that exhibit low synchronicity with nearby neighbors (<12 μm) become depressed in their transmission frequency. Asynchronous electrical stimulation of individual synapses in hippocampal slices showed that this is due to a decrease in synaptic transmission efficiency. Accordingly, experimentally increasing local synchronicity, by stimulating synapses in response to spontaneous activity at neighboring synapses, stabilized synaptic transmission. Finally, blockade of the high-affinity proBDNF receptor p75(NTR) prevented the depression of asynchronously stimulated synapses. Thus, spontaneous activity drives local synaptic plasticity at individual synapses in an "out-of-sync, lose-your-link" fashion through proBDNF/p75(NTR) signaling to refine neuronal connectivity. VIDEO ABSTRACT. PMID:26182421

  20. An acetylcholine-activated microcircuit drives temporal dynamics of cortical activity

    PubMed Central

    Sur, Mriganka

    2015-01-01

    Cholinergic modulation of cortex powerfully influences information processing and brain states, causing robust desynchronization of local field potentials and strong decorrelation of responses between neurons. Here we show that intracortical cholinergic inputs to mouse visual cortex specifically and differentially drive a defined cortical microcircuit: they facilitate somatostatin-expressing (SOM) inhibitory neurons that in turn inhibit parvalbumin-expressing inhibitory neurons and pyramidal neurons. Selective optogenetic inhibition of SOM responses blocks desynchronization and decorrelation, demonstrating that direct cholinergic activation of SOM neurons is necessary for this phenomenon. Optogenetic inhibition of vasoactive intestinal peptide-expressing neurons does not block desynchronization, despite these neurons being activated at high levels of cholinergic drive. Direct optogenetic SOM activation, independent of cholinergic modulation, is sufficient to induce desynchronization. Together, these findings demonstrate a mechanistic basis for temporal structure in cortical populations, and the crucial role of neuromodulatory drive to specific inhibitory-excitatory circuits in actively shaping the dynamics of neuronal activity. PMID:25915477

  1. An acetylcholine-activated microcircuit drives temporal dynamics of cortical activity.

    PubMed

    Chen, Naiyan; Sugihara, Hiroki; Sur, Mriganka

    2015-06-01

    Cholinergic modulation of cortex powerfully influences information processing and brain states, causing robust desynchronization of local field potentials and strong decorrelation of responses between neurons. We found that intracortical cholinergic inputs to mouse visual cortex specifically and differentially drive a defined cortical microcircuit: they facilitate somatostatin-expressing (SOM) inhibitory neurons that in turn inhibit parvalbumin-expressing inhibitory neurons and pyramidal neurons. Selective optogenetic inhibition of SOM responses blocked desynchronization and decorrelation, demonstrating that direct cholinergic activation of SOM neurons is necessary for this phenomenon. Optogenetic inhibition of vasoactive intestinal peptide-expressing neurons did not block desynchronization, despite these neurons being activated at high levels of cholinergic drive. Direct optogenetic SOM activation, independent of cholinergic modulation, was sufficient to induce desynchronization. Together, these findings demonstrate a mechanistic basis for temporal structure in cortical populations and the crucial role of neuromodulatory drive in specific inhibitory-excitatory circuits in actively shaping the dynamics of neuronal activity. PMID:25915477

  2. Brain activity during driving with distraction: an immersive fMRI study

    PubMed Central

    Schweizer, Tom A.; Kan, Karen; Hung, Yuwen; Tam, Fred; Naglie, Gary; Graham, Simon J.

    2013-01-01

    Introduction: Non-invasive measurements of brain activity have an important role to play in understanding driving ability. The current study aimed to identify the neural underpinnings of human driving behavior by visualizing the areas of the brain involved in driving under different levels of demand, such as driving while distracted or making left turns at busy intersections. Materials and Methods: To capture brain activity during driving, we placed a driving simulator with a fully functional steering wheel and pedals in a 3.0 Tesla functional magnetic resonance imaging (fMRI) system. To identify the brain areas involved while performing different real-world driving maneuvers, participants completed tasks ranging from simple (right turns) to more complex (left turns at busy intersections). To assess the effects of driving while distracted, participants were asked to perform an auditory task while driving analogous to speaking on a hands-free device and driving. Results: A widely distributed brain network was identified, especially when making left turns at busy intersections compared to more simple driving tasks. During distracted driving, brain activation shifted dramatically from the posterior, visual and spatial areas to the prefrontal cortex. Conclusions: Our findings suggest that the distracted brain sacrificed areas in the posterior brain important for visual attention and alertness to recruit enough brain resources to perform a secondary, cognitive task. The present findings offer important new insights into the scientific understanding of the neuro-cognitive mechanisms of driving behavior and lay down an important foundation for future clinical research. PMID:23450757

  3. Vision Drives Correlated Activity without Patterned Spontaneous Activity in Developing Xenopus Retina

    PubMed Central

    Demas, James A.; Payne, Hannah; Cline, Hollis T.

    2011-01-01

    Developing amphibians need vision to avoid predators and locate food before visual system circuits fully mature. Xenopus tadpoles can respond to visual stimuli as soon as retinal ganglion cells (RGCs) innervate the brain, however, in mammals, chicks and turtles, RGCs reach their central targets many days, or even weeks, before their retinas are capable of vision. In the absence of vision, activity-dependent refinement in these amniote species is mediated by waves of spontaneous activity that periodically spread across the retina, correlating the firing of action potentials in neighboring RGCs. Theory suggests that retinorecipient neurons in the brain use patterned RGC activity to sharpen the retinotopy first established by genetic cues. We find that in both wild type and albino Xenopus tadpoles, RGCs are spontaneously active at all stages of tadpole development studied, but their population activity never coalesces into waves. Even at the earliest stages recorded, visual stimulation dominates over spontaneous activity and can generate patterns of RGC activity similar to the locally correlated spontaneous activity observed in amniotes. In addition, we show that blocking AMPA and NMDA type glutamate receptors significantly decreases spontaneous activity in young Xenopus retina, but that blocking GABAA receptor blockers does not. Our findings indicate that vision drives correlated activity required for topographic map formation. They further suggest that developing retinal circuits in the two major subdivisions of tetrapods, amphibians and amniotes, evolved different strategies to supply appropriately patterned RGC activity to drive visual circuit refinement. PMID:21312343

  4. Learning Activity Packets for Auto Mechanics II. Section C--Drive Train.

    ERIC Educational Resources Information Center

    Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    Five learning activity packets (LAPs) are provided for the instructional area of drive train in the auto mechanics II program. They accompany an instructor's guide available separately. The LAPs outline the study activities and performance tasks for these five units: (1) clutch assembly, (2) standard transmission, (3) drive lines, (4) rear axle,…

  5. Driving an Active Vibration Balancer to Minimize Vibrations at the Fundamental and Harmonic Frequencies

    NASA Technical Reports Server (NTRS)

    Holliday, Ezekiel S. (Inventor)

    2014-01-01

    Vibrations of a principal machine are reduced at the fundamental and harmonic frequencies by driving the drive motor of an active balancer with balancing signals at the fundamental and selected harmonics. Vibrations are sensed to provide a signal representing the mechanical vibrations. A balancing signal generator for the fundamental and for each selected harmonic processes the sensed vibration signal with adaptive filter algorithms of adaptive filters for each frequency to generate a balancing signal for each frequency. Reference inputs for each frequency are applied to the adaptive filter algorithms of each balancing signal generator at the frequency assigned to the generator. The harmonic balancing signals for all of the frequencies are summed and applied to drive the drive motor. The harmonic balancing signals drive the drive motor with a drive voltage component in opposition to the vibration at each frequency.

  6. Active training and driving-specific feedback improve older drivers' visual search prior to lane changes

    PubMed Central

    2012-01-01

    Background Driving retraining classes may offer an opportunity to attenuate some effects of aging that may alter driving skills. Unfortunately, there is evidence that classroom programs (driving refresher courses) do not improve the driving performance of older drivers. The aim of the current study was to evaluate if simulator training sessions with video-based feedback can modify visual search behaviors of older drivers while changing lanes in urban driving. Methods In order to evaluate the effectiveness of the video-based feedback training, 10 older drivers who received a driving refresher course and feedback about their driving performance were tested with an on-road standardized evaluation before and after participating to a simulator training program (Feedback group). Their results were compared to a Control group (12 older drivers) who received the same refresher course and in-simulator active practice as the Feedback group without receiving driving-specific feedback. Results After attending the training program, the Control group showed no increase in the frequency of the visual inspection of three regions of interests (rear view and left side mirrors, and blind spot). In contrast, for the Feedback group, combining active training and driving-specific feedbacks increased the frequency of blind spot inspection by 100% (32.3 to 64.9% of verification before changing lanes). Conclusions These results suggest that simulator training combined with driving-specific feedbacks helped older drivers to improve their visual inspection strategies, and that in-simulator training transferred positively to on-road driving. In order to be effective, it is claimed that driving programs should include active practice sessions with driving-specific feedbacks. Simulators offer a unique environment for developing such programs adapted to older drivers' needs. PMID:22385499

  7. Sleep Disturbances and Adverse Driving Events in a Predominantly Male Cohort of Active Older Drivers

    PubMed Central

    Vaz Fragoso, Carlos A.; Araujo, Katy L.B.; Van Ness, Peter H.; Marottoli, Richard A.

    2010-01-01

    OBJECTIVES To evaluate the association between sleep disturbances and adverse driving events among active older drivers. DESIGN Longitudinal. PARTICIPANTS 430 older persons (mean age 78.5 years, 84.9% male), who drove at least once-a-week. MEASUREMENTS Baseline measures included self-reported driving patterns and sleep questionnaires—Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), and Sleep Apnea Clinical Score (SACS). The primary outcome was an adverse driving event, based on self-report and driving records, and categorized as a crash or traffic-infraction (composite-I), or as a crash, traffic-infraction, near-crash, or getting lost (composite-II). RESULTS Participants reported driving a median of 17.0 miles/day, with 96.7% (416/430) driving daily or every-other-day. Although 26.0% (112/430) had insomnia (ISI≥8), 19.3% (83/430) had daytime drowsiness (ESS≥10), and 19.9% (84/422) had high sleep apnea risk (SACS>15), the median scores for the ISI, ESS, and SACS were normal at 3.0, 6.0, and 8.0, respectively, and drowsy-driving was reported by only 5.1%. Over a period of up to 2-years, 24.9% (104/418) and 51.4% (215/418) of participants had a composite-I and -II driving event, respectively. In unadjusted and adjusted multivariable models, insomnia, daytime drowsiness, and high sleep apnea risk were not associated with a composite-I or –II driving event. CONCLUSION In a predominantly male cohort of active older drivers, sleep disturbances were mild and not associated with adverse driving events. Accordingly, and because older persons are known to self-regulate driving practices, future studies should evaluate whether sleep disturbances are more important as a mechanism that underlies driving cessation, rather than compromising driving safety. PMID:20929465

  8. Piled Embankment Design Comparison

    NASA Astrophysics Data System (ADS)

    Drusa, Marián; Kais, Ladislav; Vlček, Jozef; Mečár, Martin

    2015-05-01

    There are currently several national standards or regulations for the design of the piled embankment, providing suitable solutions for foundation of transport structure on soft, high compressible subsoil, [1]. The most widely used and the best-known standard is British Standard BS8006 [2], which was confronted with another analytical design methodologies (Ebgeo, CUR). Today's popularity and versatility of FEM numerical models brings many advantages, which analytical methods cannot achieved, but must be verified by proposed scaled physical model, which was currently being developed by Department of Geotechnics, University of Žilina.

  9. Improving detection of avalanches on a conical bead pile

    NASA Astrophysics Data System (ADS)

    Vajpeyi, Avi; Lehman, Susan; Dahmen, Karin; Leblanc, Michael; Uhl, Jonathan

    A conical bead pile subject to slow driving and an external magnetic field is used as a simple system to investigate the variations in the avalanche size probability distribution function. Steel beads are dropped onto the pile from different heights and at different strengths of applied magnetic field. Avalanches are recorded by the change in mass as beads fall off the pile. Experimentally we observe an increasing deviation from power law behavior as the field and thus cohesion between the beads increases. We compare our experimental results for the probability distribution function to the results of an analytic theory from a mean-field model of slip avalanches [Dahmen, Nat Phys 7, 554 (2011)]. The model also makes predictions for avalanche duration, which is not measurable with the existing system. To more fully characterize the avalanching behavior of the pile over time, a high-speed camera has been added to the system to record the largest avalanches and allow more detailed analysis. The conical pile geometry presents a challenge for observation and particle tracking over the full pile. Our implementation scheme and preliminary results from the video analysis are presented. Research supported by NSF CBET 1336116 and 1336634.

  10. Current Research Activities in Drive System Technology in Support of the NASA Rotorcraft Program

    NASA Technical Reports Server (NTRS)

    Handschuh, Robert F.; Zakrajsek, James J.

    2006-01-01

    Drive system technology is a key area for improving rotorcraft performance, noise/vibration reduction, and reducing operational and manufacturing costs. An overview of current research areas that support the NASA Rotorcraft Program will be provided. Work in drive system technology is mainly focused within three research areas: advanced components, thermal behavior/emergency lubrication system operation, and diagnostics/prognostics (also known as Health and Usage Monitoring Systems (HUMS)). Current research activities in each of these activities will be presented. Also, an overview of the conceptual drive system requirements and possible arrangements for the Heavy Lift Rotorcraft program will be reviewed.

  11. SOX9 drives WNT pathway activation in prostate cancer

    PubMed Central

    Ma, Fen; Ye, Huihui; He, Housheng Hansen; Gerrin, Sean J.; Chen, Sen; Tanenbaum, Benjamin A.; Sowalsky, Adam G.; He, Lingfeng; Wang, Hongyun; Balk, Steven P.; Yuan, Xin

    2016-01-01

    The transcription factor SOX9 is critical for prostate development, and dysregulation of SOX9 is implicated in prostate cancer (PCa). However, the SOX9-dependent genes and pathways involved in both normal and neoplastic prostate epithelium are largely unknown. Here, we performed SOX9 ChIP sequencing analysis and transcriptome profiling of PCa cells and determined that SOX9 positively regulates multiple WNT pathway genes, including those encoding WNT receptors (frizzled [FZD] and lipoprotein receptor-related protein [LRP] family members) and the downstream β-catenin effector TCF4. Analyses of PCa xenografts and clinical samples both revealed an association between the expression of SOX9 and WNT pathway components in PCa. Finally, treatment of SOX9-expressing PCa cells with a WNT synthesis inhibitor (LGK974) reduced WNT pathway signaling in vitro and tumor growth in murine xenograft models. Together, our data indicate that SOX9 expression drives PCa by reactivating the WNT/β−catenin signaling that mediates ductal morphogenesis in fetal prostate and define a subgroup of patients who would benefit from WNT-targeted therapy. PMID:27043282

  12. Acoustic emission characteristics of subsoil subjected to vertical pile loading in sand

    NASA Astrophysics Data System (ADS)

    Mao, Wuwei; Aoyama, Shogo; Goto, Shigeru; Towhata, Ikuo

    2015-08-01

    The response of the subsoil subjected to pile loading is crucial to clarify the bearing mechanism of pile foundations. This study presents a novel acoustic emission (AE) method to monitor the subsoil behavior in a model pile testing system. The AE testing aims to capture the "micro-noises" released from sand grain dislocation and crushing around the pile shaft during penetration. The correlations between the pile settlement and the AE characteristics including count, amplitude and energy are revealed and discussed, highlighting that the ground density and the shear zone formed during pile penetration mainly affect the AE behavior. The results also suggest that the yielding of ground can be determined based on the development of the AE activity. The technique shows promise as an in-situ methodology for monitoring of subsoil behavior during the process of pile loading.

  13. Mapping of noise impact provoked by the execution of foundation piles at high rise building sites.

    PubMed

    de Araújo, Adolpho Guido; Gusmão, Alexandre Duarte; Rabbani, Emilia Rahnemay Kohman; Fucale, Stela Paulino

    2012-01-01

    The objective of this work is to map, in a limited area inside and outside of the worksite, the environmental impact generated by sound pollution coming from the driving of foundation piles for high rise buildings, as well as to observe and check if the noise levels produced by the emitting source are tolerable in the urban environment. The methodology of the work includes a survey of technical references about the subject; measurement of noises surrounding the worksite during the foundation phase for four distinct buildings, with different types of piles: prefabricated piles, continuous helical displacement piles , traditional compaction piles and Terra Probe compaction piles. A grid of points was built due to the time of driving and after that the measurements of environmental noises were performed emitted by the execution of each type of pile using a sound level meter. The interpretation of the measurements and their impacts on the neighborhood of the building were performed using the computational tool Suffer for creating noise level contours. The X and Y axes of the grid represent the distances in meters of the area studied and the Z axis represents the noise measured in dB. The contours developed represent the mapping of the noise at the worksites and their surroundings. The mapping of the urban impact of noise, the measurement of its dimensions, and the examination of its propagation around the building are important subsides to adequate individual and collective protection procedures. Seventy one points were measured at four building sites with different types of piles, and the results showed that at only three points was the noise within the limits of the Municipal Law of Recife of 70 dB, which proves the relevance of the research. Finally, the comparative analysis between the four types of piles shows that the continuous helical displacement pile emits the lowest noise level among the four pile types studied. PMID:22317218

  14. An Experimental Study on Pile Spacing Effects under Lateral Loading in Sand

    PubMed Central

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2013-01-01

    Grouped and single pile behavior differs owing to the impacts of the pile-to-pile interaction. Ultimate lateral resistance and lateral subgrade modulus within a pile group are known as the key parameters in the soil-pile interaction phenomenon. In this study, a series of experimental investigation was carried out on single and group pile subjected to monotonic lateral loadings. Experimental investigations were conducted on twelve model pile groups of configurations 1 × 2, 1 × 3, 2 × 2, 3 × 3, and 3 × 2 for embedded length-to-diameter ratio l/d = 32 into loose and dense sand, spacing from 3 to 6 pile diameter, in parallel and series arrangement. The tests were performed in dry sand from Johor Bahru, Malaysia. To reconstruct the sand samples, the new designed apparatus, Mobile Pluviator, was adopted. The ultimate lateral load is increased 53% in increasing of s/d from 3 to 6 owing to effects of sand relative density. An increasing of the number of piles in-group decreases the group efficiency owing to the increasing of overlapped stress zones and active wedges. A ratio of s/d more than 6d is large enough to eliminate the pile-to-pile interaction and the group effects. It may be more in the loose sand. PMID:24453900

  15. An experimental study on pile spacing effects under lateral loading in sand.

    PubMed

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2013-01-01

    Grouped and single pile behavior differs owing to the impacts of the pile-to-pile interaction. Ultimate lateral resistance and lateral subgrade modulus within a pile group are known as the key parameters in the soil-pile interaction phenomenon. In this study, a series of experimental investigation was carried out on single and group pile subjected to monotonic lateral loadings. Experimental investigations were conducted on twelve model pile groups of configurations 1 × 2, 1 × 3, 2 × 2, 3 × 3, and 3 × 2 for embedded length-to-diameter ratio l/d = 32 into loose and dense sand, spacing from 3 to 6 pile diameter, in parallel and series arrangement. The tests were performed in dry sand from Johor Bahru, Malaysia. To reconstruct the sand samples, the new designed apparatus, Mobile Pluviator, was adopted. The ultimate lateral load is increased 53% in increasing of s/d from 3 to 6 owing to effects of sand relative density. An increasing of the number of piles in-group decreases the group efficiency owing to the increasing of overlapped stress zones and active wedges. A ratio of s/d more than 6d is large enough to eliminate the pile-to-pile interaction and the group effects. It may be more in the loose sand. PMID:24453900

  16. Test Pile Reactivity Loss Due to Trichloroethylene

    SciTech Connect

    Plumlee, K.E.

    2001-03-09

    The presence of trichloroethylene in the test pile caused a continual decrease in pile reactivity. A system which removed, purified, and returned 12,000 cfh helium to the pile has held contamination to a negligible level and has permitted normal pile operation.

  17. 40 CFR 264.554 - Staging piles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... existing permit (for example, RAP), closure plan, or order be modified to allow me to use a staging pile? (1) To modify a permit, other than a RAP, to incorporate a staging pile or staging pile operating... under § 270.42 of this chapter. (2) To modify a RAP to incorporate a staging pile or staging...

  18. 40 CFR 264.554 - Staging piles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... existing permit (for example, RAP), closure plan, or order be modified to allow me to use a staging pile? (1) To modify a permit, other than a RAP, to incorporate a staging pile or staging pile operating... under § 270.42 of this chapter. (2) To modify a RAP to incorporate a staging pile or staging...

  19. 40 CFR 264.554 - Staging piles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... existing permit (for example, RAP), closure plan, or order be modified to allow me to use a staging pile? (1) To modify a permit, other than a RAP, to incorporate a staging pile or staging pile operating... under § 270.42 of this chapter. (2) To modify a RAP to incorporate a staging pile or staging...

  20. 40 CFR 264.554 - Staging piles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... existing permit (for example, RAP), closure plan, or order be modified to allow me to use a staging pile? (1) To modify a permit, other than a RAP, to incorporate a staging pile or staging pile operating... under § 270.42 of this chapter. (2) To modify a RAP to incorporate a staging pile or staging...

  1. Eruptions that Drive Coronal Jets in a Solar Active Region

    NASA Technical Reports Server (NTRS)

    Sterling, Alphonse C.; Moore, Ronald L.; Falconer, David A.; Panesar, Navdeep K.; Akiyama, Sachiko; Yashiro, Seiji; Gopalswamy, Nat

    2016-01-01

    Solar coronal jets are common in both coronal holes and in active regions (e.g., Shibata et al. 1992, Shimojo et al. 1996, Cirtain et al. 2007. Savcheva et al. 2007). Recently, Sterling et al. (2015), using data from Hinode/XRT and SDO/AIA, found that coronal jets originating in polar coronal holes result from the eruption of small-scale filaments (minifilaments). The jet bright point (JBP) seen in X-rays and hotter EUV channels off to one side of the base of the jet's spire develops at the location where the minifilament erupts, consistent with the JBPs being miniature versions of typical solar flares that occur in the wake of large-scale filament eruptions. Here we consider whether active region coronal jets also result from the same minifilament-eruption mechanism, or whether they instead result from a different mechanism (e.g. Yokoyama & Shibata 1995). We present observations of an on-disk active region (NOAA AR 11513) that produced numerous jets on 2012 June 30, using data from SDO/AIA and HMI, and from GOES/SXI. We find that several of these active region jets also originate with eruptions of miniature filaments (size scale 20'') emanating from small-scale magnetic neutral lines of the region. This demonstrates that active region coronal jets are indeed frequently driven by minifilament eruptions. Other jets from the active region were also consistent with their drivers being minifilament eruptions, but we could not confirm this because the onsets of those jets were hidden from our view. This work was supported by funding from NASA/LWS, NASA/HGI, and Hinode. A full report of this study appears in Sterling et al. (2016).

  2. Neighborhood environment and physical activity among older adults: do the relationships differ by driving status?

    PubMed

    Ding, Ding; Sallis, James F; Norman, Gregory J; Frank, Lawrence D; Saelens, Brian E; Kerr, Jacqueline; Conway, Terry L; Cain, Kelli; Hovell, Melbourne F; Hofstetter, C Richard; King, Abby C

    2014-07-01

    Some attributes of neighborhood environments are associated with physical activity among older adults. This study examined whether the associations were moderated by driving status. Older adults from neighborhoods differing in walkability and income completed written surveys and wore accelerometers (N = 880, mean age = 75 years, 56% women). Neighborhood environments were measured by geographic information systems and validated questionnaires. Driving status was defined on the basis of a driver's license, car ownership, and feeling comfortable to drive. Outcome variables included accelerometer-based physical activity and self-reported transport and leisure walking. Multilevel generalized linear regression was used. There was no significant Neighborhood Attribute × Driving Status interaction with objective physical activity or reported transport walking. For leisure walking, almost all environmental attributes were positive and significant among driving older adults but not among nondriving older adults (five significant interactions at p < .05). The findings suggest that driving status is likely to moderate the association between neighborhood environments and older adults' leisure walking. PMID:24084049

  3. Effect of activities of daily living status on resuming driving after stroke

    PubMed Central

    Park, Myoung-Ok; Jung, Bong-Keun

    2015-01-01

    [Purpose] This study aimed to investigate the effect of the activities of daily living status on resuming driving after stroke. [Subjects] Thirty-one participants with stroke, who visited in Korean national rehabilitation centers, were included in this study. [Methods] The activities of daily living performance and the driving ability of the participants were assessed with the Korean-Modified Barthel Index in combination with the results obtained by using a driving simulator. [Results] Significant correlations were noted among the Korean-Modified Barthel Index, on-road driving total score, reaction time, speed anticipation tests, judgment tests, and steering wheel-pedal operation tests. Results of Stepwise multiple regression also revealed that the Korean-Modified Barthel Index total score and speed anticipation, with an R2 of 52.9%. In other words, as the Korean-Modified Barthel Index total score and speed anticipation score increased and the driving performance score also increased in patients who had suffered a stroke. [Conclusion] The activities of daily living status was positively correlated with the patients’ post stroke driving ability. PMID:26834346

  4. Motolimod effectively drives immune activation in advanced cancer patients

    PubMed Central

    Dietsch, Gregory N.

    2016-01-01

    ABSTRACT A novel approach to immunotherapy is the activation of toll-like receptor 8 (TLR8). Motolimod, a selective TLR8 agonist can act in concert with approved immunotherapies to sensitize T cells and augment natural killer (NK) cell function. Despite treatment with chemotherapeutic agents and advance disease, cancer patients remain sensitive to motolimod.

  5. Bacterial activities driving arsenic speciation and solubility in marine sediments

    NASA Astrophysics Data System (ADS)

    Battaglia-Brunet, F.; Seby, F.; Crouzet, C.; Joulian, C.; Mamindy-Pajany, Y.; Guezennec, A. G.; Hurel, C.; Marmier, N.; Bataillard, P.

    2012-04-01

    Harbour and marina sediments represent particular environments, with high concentrations in organic carbon and pollutants. Over 50 million m3 of marine sediments are dredged every year in French maritime and commercial ports, to maintain the water depth suitable for navigation, and the most part of them is discharged in deeper sea zones. The present study aimed to elucidate, using a range of complementary approaches, the influence of bacterial activity on arsenic speciation and mobility in marina sediments. Two sites were considered: L'Estaque, impacted by metallurgical activities and by the commercial port of Marseille, and St-Mandrier, less polluted, affected by classical chemical pollutants associated to professional and recreational boating. Arsenic concentration was noticeably higher in l'Estaque sediment (200-350 mg/kg) than in St-Mandrier sediment (15-50 mg/kg). In the solid phases, As(III) was the dominant species in L'Estaque sediment, whereas As(V) was the main form in St Mandrier sediment. At both sites, arsenic was the major trace element detected in interstitial water. Free sulfide and thio-arsenic complexes were detected in the interstitial water of l'Estaque sediment, suggesting a role of sulfate-reduction bacterial activity on arsenic solubility. Anaerobic microcosm experiments confirmed this hypothesis, as stimulation of sulfate-reduction induced a dramatic increase of arsenic concentration in the liquid phase, linked to the formation of soluble thio-arsenic complexes. Nevertheless, microcosms performed in aerobic conditions showed that bacterial activity globally decreased the transfer of arsenic from the sediment toward the overlying water. A red-brown fine layer developed at the sediment-water interface. Altogether, these results suggest that the sediment-water interface zone and the close transition area between aerobic and anaerobic conditions host intense biogeochemical reactions involving As, Fe and S species. These reactions most probably

  6. Key gravity-sensitive signaling pathways drive T cell activation.

    PubMed

    Boonyaratanakornkit, J B; Cogoli, A; Li, C-F; Schopper, T; Pippia, P; Galleri, G; Meloni, M A; Hughes-Fulford, M

    2005-12-01

    Returning astronauts have experienced altered immune function and increased vulnerability to infection during spaceflights dating back to Apollo and Skylab. Lack of immune response in microgravity occurs at the cellular level. We analyzed differential gene expression to find gravity-dependent genes and pathways. We found inhibited induction of 91 genes in the simulated freefall environment of the random positioning machine. Altered induction of 10 genes regulated by key signaling pathways was verified using real-time RT-PCR. We discovered that impaired induction of early genes regulated primarily by transcription factors NF-kappaB, CREB, ELK, AP-1, and STAT after crosslinking the T-cell receptor contributes to T-cell dysfunction in altered gravity environments. We have previously shown that PKA and PKC are key early regulators in T-cell activation. Since the majority of the genes were regulated by NF-kappaB, CREB, and AP-1, we studied the pathways that regulated these transcription factors. We found that the PKA pathway was down-regulated in vg. In contrast, PI3-K, PKC, and its upstream regulator pLAT were not significantly down-regulated by vectorless gravity. Since NF-kappaB, AP-1, and CREB are all regulated by PKA and are transcription factors predicted by microarray analysis to be involved in the altered gene expression in vectorless gravity, the data suggest that PKA is a key player in the loss of T-cell activation in altered gravity. PMID:16210397

  7. Pile Structure Program, Projected Start Date : January 1, 2010 (Implementation).

    SciTech Connect

    Collins, Chris; Corbett, Catherine; Ebberts, Blaine

    2009-07-27

    The 2008 Federal Columbia River Power System Biological Opinion includes Reasonable and Prudent Alternative 38-Piling and Piling Dike Removal Program. This RPA directs the Action Agencies to work with the Estuary Partnership to develop and implement a piling and pile dike removal program. The program has since evolved to include modifying pile structures to enhance their habitat value and complexity by adding large woody debris. The geographic extent of the Pile Structure Program (PSP) includes all tidally-influenced portions of the lower Columbia River below Bonneville Dam; however, it will focus on the mainstem. The overarching goal of the PSP is to enhance and restore ecosystem structure and function for the recovery of federally listed salmonids through the active management of pile structures. To attain this goal, the program team developed the following objectives: (1) Develop a plan to remove or modify pile structures that have lower value to navigation channel maintenance, and in which removal or modification will present low-risk to adjacent land use, is cost-effective, and would result in increased ecosystem function. (2) Determine program benefits for juvenile salmonids and the ecosystem through a series of intensively monitored pilot projects. (3) Incorporate best available science and pilot project results into an adaptive management framework that will guide future management by prioritizing projects with the highest benefits. The PSP's hypotheses, which form the basis of the pilot project experiments, are organized into five categories: Sediment and Habitat-forming Processes, Habitat Conditions and Food Web, Piscivorous Fish, Piscivorous Birds, and Toxic Contaminant Reduction. These hypotheses are based on the effects listed in the Estuary Module (NOAA Fisheries in press) and others that emerged during literature reviews, discussions with scientists, and field visits. Using pilot project findings, future implementation will be adaptively managed to

  8. Axially Loaded Behavior of Driven PC Piles

    NASA Astrophysics Data System (ADS)

    Hsu, Shih-Tsung

    2010-05-01

    To obtain a fair load-settlement curve of a driven pile, and to evaluate the ultimate pile capacity more accurately, a numerical model was created to simulate the ground movements during a pile being driven. After the procedure, the axially loaded behaviors of the piles in silty sand were analyzed. The numerical results are compared with those results by full scale pile load tests. It was found, although the loads added on the tested piles are different from those by the numerical analyses which applied displacement increments on piles, the load-settlement behaviors of piles calculated from the numerical model were close to those measured from field tests before the piles stressed to peak. Total load, shaft friction, and point bearing do not reach peak values at the same pile settlement; furthermore, the point bearing slowly increases all the while, with no peak. However, the point bearing only contributes 10˜20% of ultimate pile capacity. No matter which relative density of silty sand, pile diameter, and pile length increased, ultimate pile capacity increased as well.

  9. RECLAMATION OF ALKALINE ASH PILES

    EPA Science Inventory

    The objective of the study was to develop methods for reclaiming ash disposal piles for the ultimate use as agricultural or forest lands. The ashes studied were strongly alkaline and contained considerable amounts of salts and toxic boron. The ashes were produced from burning bit...

  10. Pulse pile-up effects

    SciTech Connect

    Tenney, F.H.

    1983-05-01

    The energy spectrum containing the effects of all orders of pulse pileup is predicted for an idealized x-ray pulse-height-analysis system measuring randomly occurring events. Two simplifying assumptions used are first a fixed pulse resolution time and second that the measured energy of piled-up pulses is the algebraic sum of the energy associated with each pulse.

  11. Eros is a Rubble Pile

    NASA Astrophysics Data System (ADS)

    Asphaug, Erik

    2008-09-01

    Asteroid 433 Eros is regarded as "fractured monolith" or "shatter pile". But models of fragmentation and disruption (e.g. Benz and Asphaug 1999) predict that any large rocky asteroid should be transformed into a jumble of dust, gravel, talus and boulders, simply because it is much easier to comminute an asteroid than to catastrophically disrupt it. Sometimes the relatively high density of Eros is taken as evidence for a fractured monolithic structure, although the inferred bulk porosity of Eros ( 20-30%) is what one expects for a rubble pile, and is about the porosity of sand and talus. The focus here is that a rubble pile structure is contraindicated by the pronounced network of linear fault-like structures (Buczkowski et al. 2008), some of which radiate from recent large impacts such as Psyche, and which form rectangular boundaries around some of the medium-sized craters. This needs an explanation. Here it is proposed, and quantitatively addressed, that the majority of these faults occur just in the upper tens of meters, where cohesion exceeds gravitational stress even for loose piles of lunar-like regolith. Assuming Eros regolith has the cohesion ( 1 kPa) measured for lunar regolith, then faulting is expected to a depth of 10 m, directly analogous to how faults occur in the upper layers of beach sand. The fact that Eros has few steep slopes anywhere, except for the angles of repose within its craters, at a baseline of 100 m (Zuber et al. 2002), is satisfied by the hypothesis that Eros is a rubble pile rather than a shattered monolith. The low fault stress implied by the above, supports the findings of dense networks of linear structures, ubiquitous features which are otherwise difficult to explain as fractures in a rocky target which has not been disrupted or jumbled against its very low gravity.

  12. Characterisation Progress at the Windscale Pile Reactors. Challenges and Results

    SciTech Connect

    Ervin, P.F.

    2008-07-01

    The decommissioning of the Windscale Pile 1 reactor, fifty years after the 1957 fire, is one of the most technically challenging decommissioning projects in the United Kingdom, if not the world. The decommissioning is being performed by an Alliance of the United Kingdom Atomic Energy Authority (UKAEA), CH2M HILL International Nuclear Services (CHNS) Ltd. and AMEC, NNC. The 1957 Windscale Pile 1 accident is summarized. The resulting fire caused significant characterisation challenges. Challenges to intrusive characterization included hypothesized uranium hydride causing re-ignition of the core fire, unknown fuel configurations leading to a reactor criticality and graphite dust explosions. As a result, the Pile 1 facilities were sealed, isolated and managed in a monitoring and surveillance regime while plans for dismantling were developed. For years the intrusive inspection of the fire damaged region of Pile 1, estimated to contain 15 tonnes of fuel, was precluded based on safety grounds. In June of 2006 the United Kingdom Health and Safety Directorate approved a new Pile 1 safety case that successfully demonstrated that Pile 1 presents a minimal safety risk with no credible risk of a core fire, criticality or graphite dust explosion. Adoption of the new safety case enabled the intrusive inspections of the fire damaged region. Characterisation activities planned and performed since the safety case approval, were prioritised relative to the results potential to mitigate decommissioning project risks. D-Void examinations, irradiation foil hole intrusive inspections, bio-shield and thermal shield plate characterizations were performed. Results obtained allow determination of waste stream composition and confirmation of assumed design conditions. Changes to the strategic approach to safely and efficiently decommission the two Windscale Pile Reactors include waste packaging and storage facilities and confirmation of design assumptions. Fuel channel endoscope inspections

  13. Compact lossless synthetic network drive/controllers for active devices technologies

    NASA Astrophysics Data System (ADS)

    Murray, John J.; Knowles, Gareth J.; Bower, Bruce L.; Spangler, Brent L.

    1997-06-01

    EMF has demonstrated the emergence of an internal structure within the power system and drive electronics for discrete and continuous piezo-coupled systems which leads to the underlying theory of quasi-active controllers (i.e. operates at high voltage, but with no net energy consumption). If the control is lossless, then it should be possible to implement control in a way which, while it requires a power source, consumes no net energy from the power source. That is a drive/control mechanism which needs a reservoir of stored energy rather than a continuous source of power. This paper is devoted to presenting a complete solution to the implementation of this new concept which is termed a synthetic lossless realization. The synthetic circuitry implements a lossless realization of quasi-active control. The synthetic concepts and circuitry are introduced and the analog and digital microcontrollers of the controlled coupled parameters are discussed.

  14. Beta EEG reflects sensory processing in active wakefulness and homeostatic sleep drive in quiet wakefulness.

    PubMed

    Grønli, Janne; Rempe, Michael J; Clegern, William C; Schmidt, Michelle; Wisor, Jonathan P

    2016-06-01

    Markers of sleep drive (<10 Hz; slow-wave activity and theta) have been identified in the course of slow-wave sleep and wakefulness. So far, higher frequencies in the waking electroencephalogram have not been examined thoroughly as a function of sleep drive. Here, electroencephalogram dynamics were measured in epochs of active wake (wake characterized by high muscle tone) or quiet wake (wake characterized by low muscle tone). It was hypothesized that the higher beta oscillations (15-35 Hz, measured by local field potential and electroencephalography) represent fundamentally different processes in active wake and quiet wake. In active wake, sensory stimulation elevated beta activity in parallel with gamma (80-90 Hz) activity, indicative of cognitive processing. In quiet wake, beta activity paralleled slow-wave activity (1-4 Hz) and theta (5-8 Hz) in tracking sleep need. Cerebral lactate concentration, a measure of cerebral glucose utilization, increased during active wake whereas it declined during quiet wake. Mathematical modelling of state-dependent dynamics of cortical lactate concentration was more precisely predictive when quiet wake and active wake were included as two distinct substates rather than a uniform state of wakefulness. The extent to which lactate concentration declined in quiet wake and increased in active wake was proportionate to the amount of beta activity. These data distinguish quiet wake from active wake. Quiet wake, particularly when characterized by beta activity, is permissive to metabolic and electrophysiological changes that occur in slow-wave sleep. These data urge further studies on state-dependent beta oscillations across species. PMID:26825702

  15. Are some meteoroids rubble piles?

    NASA Astrophysics Data System (ADS)

    Borovička, Jiri

    2015-08-01

    It is generally accepted that some asteroids are rubble piles, i.e. strengthless aggregates of boulders of various sizes held together only by mutual gravity. This is particularly true for asteroids in the size range from ~ 200 m to 10 km, whose rotations are in almost all cases slower that the surface disruption barrier, at which the centrifugal force would exceed the gravitational force. On the other hand, smaller asteroids often rotate rapidly.Recently, Sánchez and Scheeres (2014, Meteorit. Planet. Sci. 49, 788) proposed that rubble piles may have some cohesive strength provided by van der Waals forces between small grains. They estimate the strength to be about 25 Pa. Such a low strength would be sufficient to hold some rapidly rotating small asteroids together against centrifugal force, even if they were rubble piles. In particular, Sánchez and Scheeres (2014) argued that asteroid 2008 TC3 was a rubble pile. That asteroid entered the Earth’s atmosphere and produced meteorites Almahata Sitta.Asteroids and meteoroids entering the atmosphere are subject to dynamic pressure p = ρv2, where ρ is atmospheric density and v is velocity. It can be expected that they break-up when the dynamic pressure exceeds their strength. Fragmentation of meteoroids is indeed common. For asteroidal bodies it usually occurs at pressures 0.1 - 10 MPa (Popova et al. 2011, Meteorit. Planet. Sci. 46, 1525). For example, the main break-up of 2008 TC3 occurred at 0.9 MPa. These pressures are lower than the strength of solid meteoric rocks but dramatically exceed the expected strength for rubble piles. They best correspond to fractured stones. Nevertheless, the first break-up of rubble piles can be expected at heights above 100 km, earlier than the intensive evaporation starts and the fireball begins to be visible. Is it possible that some meteoroids were broken-up already at the beginning of observation? I will discuss this question generally and also for several specific cases of

  16. 76 FR 4300 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-25

    ...NMFS has received an application from the U.S. Navy (Navy) for an Incidental Harassment Authorization (IHA) to take marine mammals, by harassment, incidental to pile driving activities as part of a test pile program. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to issue an IHA to the Navy to take, by Level B Harassment only, five species of......

  17. Are some meteoroids rubble piles?

    NASA Astrophysics Data System (ADS)

    Borovička, Jiří

    2016-01-01

    The possibility that some meteoroids in the size range 1 - 20 meters are rubble piles i.e. assembles of boulders of various sizes held together only by small van der Waals forces, is investigated. Such meteoroids are expected to start disrupting into individual pieces during the atmospheric entry at very low dynamic pressures of ~ 25 Pa, even before the onset of ablation. The heterogeneous bodies as Almahata Sitta (asteroid 2008 TC3) and Benešov are primary candidates for rubble piles. Nevertheless, by analyzing the deceleration, wake, and light curve of the Benešov bolide, we found that the meteoroid disruption started only at a height of 70 km under dynamic pressure of 50 kPa. No evidence for a very early fragmentation was found also for the Chelyabinsk event.

  18. Non-Ionotropic NMDA Receptor Signaling Drives Activity-Induced Dendritic Spine Shrinkage

    PubMed Central

    Stein, Ivar S.; Gray, John A.

    2015-01-01

    The elimination of dendritic spine synapses is a critical step in the refinement of neuronal circuits during development of the cerebral cortex. Several studies have shown that activity-induced shrinkage and retraction of dendritic spines depend on activation of the NMDA-type glutamate receptor (NMDAR), which leads to influx of extracellular calcium ions and activation of calcium-dependent phosphatases that modify regulators of the spine cytoskeleton, suggesting that influx of extracellular calcium ions drives spine shrinkage. Intriguingly, a recent report revealed a novel non-ionotropic function of the NMDAR in the regulation of synaptic strength, which relies on glutamate binding but is independent of ion flux through the receptor (Nabavi et al., 2013). Here, we tested whether non-ionotropic NMDAR signaling could also play a role in driving structural plasticity of dendritic spines. Using two-photon glutamate uncaging and time-lapse imaging of rat hippocampal CA1 neurons, we show that low-frequency glutamatergic stimulation results in shrinkage of dendritic spines even in the presence of the NMDAR d-serine/glycine binding site antagonist 7-chlorokynurenic acid (7CK), which fully blocks NMDAR-mediated currents and Ca2+ transients. Notably, application of 7CK or MK-801 also converts spine enlargement resulting from a high-frequency uncaging stimulus into spine shrinkage, demonstrating that strong Ca2+ influx through the NMDAR normally overcomes a non-ionotropic shrinkage signal to drive spine growth. Our results support a model in which NMDAR signaling, independent of ion flux, drives structural shrinkage at spiny synapses. SIGNIFICANCE STATEMENT Dendritic spine elimination is vital for the refinement of neural circuits during development and has been linked to improvements in behavioral performance in the adult. Spine shrinkage and elimination have been widely accepted to depend on Ca2+ influx through NMDA-type glutamate receptors (NMDARs) in conjunction with long

  19. Active and Passive Fatigue in Simulated Driving: Discriminating Styles of Workload Regulation and Their Safety Impacts

    PubMed Central

    Saxby, Dyani J.; Matthews, Gerald; Warm, Joel S.; Hitchcock, Edward M.; Neubauer, Catherine

    2015-01-01

    Despite the known dangers of driver fatigue, it is a difficult construct to study empirically. Different forms of task-induced fatigue may differ in their effects on driver performance and safety. Desmond and Hancock (2001) defined active and passive fatigue states that reflect different styles of workload regulation. In 2 driving simulator studies we investigated the multidimensional subjective states and safety outcomes associated with active and passive fatigue. Wind gusts were used to induce active fatigue, and full vehicle automation to induce passive fatigue. Drive duration was independently manipulated to track the development of fatigue states over time. Participants were undergraduate students. Study 1 (N = 108) focused on subjective response and associated cognitive stress processes, while Study 2 (N = 168) tested fatigue effects on vehicle control and alertness. In both studies the 2 fatigue manipulations produced different patterns of subjective response reflecting different styles of workload regulation, appraisal, and coping. Active fatigue was associated with distress, overload, and heightened coping efforts, whereas passive fatigue corresponded to large-magnitude declines in task engagement, cognitive underload, and reduced challenge appraisal. Study 2 showed that only passive fatigue reduced alertness, operationalized as speed of braking and steering responses to an emergency event. Passive fatigue also increased crash probability, but did not affect a measure of vehicle control. Findings support theories that see fatigue as an outcome of strategies for managing workload. The distinction between active and passive fatigue is important for assessment of fatigue and for evaluating automated driving systems which may induce dangerous levels of passive fatigue. PMID:24041288

  20. Actomyosin dynamics drive local membrane component organization in an in vitro active composite layer.

    PubMed

    Köster, Darius Vasco; Husain, Kabir; Iljazi, Elda; Bhat, Abrar; Bieling, Peter; Mullins, R Dyche; Rao, Madan; Mayor, Satyajit

    2016-03-22

    The surface of a living cell provides a platform for receptor signaling, protein sorting, transport, and endocytosis, whose regulation requires the local control of membrane organization. Previous work has revealed a role for dynamic actomyosin in membrane protein and lipid organization, suggesting that the cell surface behaves as an active composite composed of a fluid bilayer and a thin film of active actomyosin. We reconstitute an analogous system in vitro that consists of a fluid lipid bilayer coupled via membrane-associated actin-binding proteins to dynamic actin filaments and myosin motors. Upon complete consumption of ATP, this system settles into distinct phases of actin organization, namely bundled filaments, linked apolar asters, and a lattice of polar asters. These depend on actin concentration, filament length, and actin/myosin ratio. During formation of the polar aster phase, advection of the self-organizing actomyosin network drives transient clustering of actin-associated membrane components. Regeneration of ATP supports a constitutively remodeling actomyosin state, which in turn drives active fluctuations of coupled membrane components, resembling those observed at the cell surface. In a multicomponent membrane bilayer, this remodeling actomyosin layer contributes to changes in the extent and dynamics of phase-segregating domains. These results show how local membrane composition can be driven by active processes arising from actomyosin, highlighting the fundamental basis of the active composite model of the cell surface, and indicate its relevance to the study of membrane organization. PMID:26929326

  1. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Coal mine waste: Refuse piles. 816.83 Section 816.83 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PERMANENT PROGRAM PERFORMANCE STANDARDS PERMANENT PROGRAM PERFORMANCE STANDARDS-SURFACE MINING ACTIVITIES § 816.83 Coal mine waste: Refuse...

  2. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Coal mine waste: Refuse piles. 817.83 Section 817.83 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PERMANENT PROGRAM PERFORMANCE STANDARDS PERMANENT PROGRAM PERFORMANCE STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.83 Coal mine waste:...

  3. Driver hand activity analysis in naturalistic driving studies: challenges, algorithms, and experimental studies

    NASA Astrophysics Data System (ADS)

    Ohn-Bar, Eshed; Martin, Sujitha; Trivedi, Mohan Manubhai

    2013-10-01

    We focus on vision-based hand activity analysis in the vehicular domain. The study is motivated by the overarching goal of understanding driver behavior, in particular as it relates to attentiveness and risk. First, the unique advantages and challenges for a nonintrusive, vision-based solution are reviewed. Next, two approaches for hand activity analysis, one relying on static (appearance only) cues and another on dynamic (motion) cues, are compared. The motion-cue-based hand detection uses temporally accumulated edges in order to maintain the most reliable and relevant motion information. The accumulated image is fitted with ellipses in order to produce the location of the hands. The method is used to identify three hand activity classes: (1) two hands on the wheel, (2) hand on the instrument panel, (3) hand on the gear shift. The static-cue-based method extracts features in each frame in order to learn a hand presence model for each of the three regions. A second-stage classifier (linear support vector machine) produces the final activity classification. Experimental evaluation with different users and environmental variations under real-world driving shows the promise of applying the proposed systems for both postanalysis of captured driving data as well as for real-time driver assistance.

  4. High and Low Activity Rats: Elevated intrinsic physical activity drives resistance to diet induced obesity in non-bred rats

    PubMed Central

    Perez-Leighton, Claudio E.; Boland, Kelsey; Billington, Charles; Kotz, Catherine M.

    2012-01-01

    Humans and rodents show large variability in their individual sensitivity to diet-induced obesity, which has been associated with differences in intrinsic spontaneous physical activity (SPA). Evidence from genetic and out-bred rat obesity models shows that higher activity of the orexin peptides results in higher intrinsic SPA and protection against diet-induced obesity. Based on this, we hypothesized that naturally occurring variation in SPA and orexin signaling activity is sufficient to drive differences in sensitivity to diet-induced obesity. We analyzed orexin activity and sensitivity to diet-induced obesity in non-manipulated male Sprague Dawley rats selected for high and low intrinsic SPA. Our results defined a new model of differential DIO sensitivity, the high-activity and low activity-rats, and suggest that naturally occurring variations in intrinsic SPA cause differences in energy expenditure that are mediated by orexin signaling and alter DIO sensitivity. PMID:23404834

  5. Integrin adhesion drives the emergent polarization of active cytoskeletal stresses to pattern cell delamination

    PubMed Central

    Meghana, C.; Ramdas, Nisha; Hameed, Feroz Meeran; Rao, Madan; Shivashankar, G. V.; Narasimha, Maithreyi

    2011-01-01

    Tissue patterning relies on cellular reorganization through the interplay between signaling pathways and mechanical stresses. Their integration and spatiotemporal coordination remain poorly understood. Here we investigate the mechanisms driving the dynamics of cell delamination, diversely deployed to extrude dead cells or specify distinct cell fates. We show that a local mechanical stimulus (subcellular laser perturbation) releases cellular prestress and triggers cell delamination in the amnioserosa during Drosophila dorsal closure, which, like spontaneous delamination, results in the rearrangement of nearest neighbors around the delaminating cell into a rosette. We demonstrate that a sequence of “emergent cytoskeletal polarities” in the nearest neighbors (directed myosin flows, lamellipodial growth, polarized actomyosin collars, microtubule asters), triggered by the mechanical stimulus and dependent on integrin adhesion, generate active stresses that drive delamination. We interpret these patterns in the language of active gels as asters formed by active force dipoles involving surface and body stresses generated by each cell and liken delamination to mechanical yielding that ensues when these stresses exceed a threshold. We suggest that differential contributions of adhesion, cytoskeletal, and external stresses must underlie differences in spatial pattern. PMID:21571643

  6. Lower Cortisol Activity is Associated with First-Time Driving while Impaired

    PubMed Central

    Couture, Sophie; Ouimet, Marie Claude; Gianoulakis, Christina; Tremblay, Jacques; Ng Ying Kin, NMK; Brochu, Serge; Pruessner, Jens; Dedovic, Katarina; Brown, Thomas G

    2015-01-01

    Driving while impaired (DWI) is a grave and persistent high-risk behavior. Previous work demonstrated that DWI recidivists had attenuated cortisol reactivity compared to non-DWI drivers. This suggests that cortisol is a neurobiological marker of high-risk driving. The present study tested the hypothesis that this initial finding would extend to first-time DWI (fDWI) offenders compared to non-DWI drivers. Male fDWI offenders (n = 139) and non-DWI drivers (n = 31) were exposed to a stress task, and their salivary cortisol activity (total output and reactivity) was measured. Participants also completed questionnaires on sensation seeking, impulsivity, substance use, and engagement in risky and criminal behaviors. As hypothesized, fDWI offenders, compared to non-DWI drivers, had lower cortisol reactivity; fDWI offenders also showed lower total output. In addition, cortisol activity was the most important predictor of group membership, after accounting for alcohol misuse patterns and consequences and other personality and problem behavior characteristics. The findings indicate that attenuated cortisol activity is an independent factor associated with DWI offending risk at an earlier stage in the DWI trajectory than previously detected. PMID:25922575

  7. Lower Cortisol Activity is Associated with First-Time Driving while Impaired.

    PubMed

    Couture, Sophie; Ouimet, Marie Claude; Gianoulakis, Christina; Tremblay, Jacques; Ng Ying Kin, Nmk; Brochu, Serge; Pruessner, Jens; Dedovic, Katarina; Brown, Thomas G

    2015-01-01

    Driving while impaired (DWI) is a grave and persistent high-risk behavior. Previous work demonstrated that DWI recidivists had attenuated cortisol reactivity compared to non-DWI drivers. This suggests that cortisol is a neurobiological marker of high-risk driving. The present study tested the hypothesis that this initial finding would extend to first-time DWI (fDWI) offenders compared to non-DWI drivers. Male fDWI offenders (n = 139) and non-DWI drivers (n = 31) were exposed to a stress task, and their salivary cortisol activity (total output and reactivity) was measured. Participants also completed questionnaires on sensation seeking, impulsivity, substance use, and engagement in risky and criminal behaviors. As hypothesized, fDWI offenders, compared to non-DWI drivers, had lower cortisol reactivity; fDWI offenders also showed lower total output. In addition, cortisol activity was the most important predictor of group membership, after accounting for alcohol misuse patterns and consequences and other personality and problem behavior characteristics. The findings indicate that attenuated cortisol activity is an independent factor associated with DWI offending risk at an earlier stage in the DWI trajectory than previously detected. PMID:25922575

  8. Pile Model Tests Using Strain Gauge Technology

    NASA Astrophysics Data System (ADS)

    Krasiński, Adam; Kusio, Tomasz

    2015-09-01

    Ordinary pile bearing capacity tests are usually carried out to determine the relationship between load and displacement of pile head. The measurement system required in such tests consists of force transducer and three or four displacement gauges. The whole system is installed at the pile head above the ground level. This approach, however, does not give us complete information about the pile-soil interaction. We can only determine the total bearing capacity of the pile, without the knowledge of its distribution into the shaft and base resistances. Much more information can be obtained by carrying out a test of instrumented pile equipped with a system for measuring the distribution of axial force along its core. In the case of pile model tests the use of such measurement is difficult due to small scale of the model. To find a suitable solution for axial force measurement, which could be applied to small scale model piles, we had to take into account the following requirements: - a linear and stable relationship between measured and physical values, - the force measurement accuracy of about 0.1 kN, - the range of measured forces up to 30 kN, - resistance of measuring gauges against aggressive counteraction of concrete mortar and against moisture, - insensitivity to pile bending, - economical factor. These requirements can be fulfilled by strain gauge sensors if an appropriate methodology is used for test preparation (Hoffmann [1]). In this paper, we focus on some aspects of the application of strain gauge sensors for model pile tests. The efficiency of the method is proved on the examples of static load tests carried out on SDP model piles acting as single piles and in a group.

  9. Pile Spacing Optimization of Short Piled Raft Foundation System for Obtaining Minimum Settlement on Peat

    NASA Astrophysics Data System (ADS)

    Suro, S. M.; Bakar, I.; Sulaeman, A.

    2016-07-01

    Short Piled Raft is a modified piled raft foundation system, which represents combination between raft foundation and pile foundation, but the length of pile is relatively shorter. The basic concept of the Short Piled Raft foundation system considers the passive soil pressure creating a stiff condition of slab-pile system. This means that the thin concrete slab floats on the supporting soil, while the piles serve as stiffeners concrete slab and also to reduce settlement of the foundation. Slab to pile ratio of such system has been mentioned by several researchers, however the optimum pile spacing of stability performance for obtaining minimum settlement on peat haven't been clearly discussed. In this study, finite element method to simulate the stability performance related to settlement of Short Piled Raft foundation system was used. Short Piled Raft foundation system with concrete slab of 7.0 m x 7.0 m square was assumed to be built on peat with the thickness of 3.5 m. The material properties of pile and raft were constant. The outer diameter of galvanized steel pipe as pile was 0.30 m; raft thickness was considered to be constant of 0.15 m and the length of pile was 3.0 m, while the pile spacing varied from 0.50 to 3.00 m. Point load varied from 0 to 100 kN with increment of 20 kN was also considered as a static load, acted on the centre of the concrete slab. Optimization was done by comparing each numerical result of simulations, thus conclusion can easily be drawn. The optimum pile spacing was 1.00 m which produced minimum settlement of 30.11 mm under the load of 100 kN.

  10. Windscale pile reactors - Decommissioning progress on a fifty year legacy

    SciTech Connect

    Sexton, Richard J.

    2007-07-01

    The decommissioning of the Windscale Pile 1 reactor, fifty years after the 1957 fire, is one of the most technically challenging decommissioning projects in the UK, if not the world. This paper presents a summary of the 1957 Windscale Pile 1 accident, its unique challenges and a new technical approach developed to safely and efficiently decommission the two Windscale Pile Reactors. The reactors will be decommissioned using a top down approach that employs an array of light weight, carbon fiber, high payload robotic arms to remove the damaged fuel, the graphite core, activated metals and concrete. This relatively conventional decommissioning approach has been made possible by a recently completed technical assessment of reactor core fire and criticality risk which concluded that these types of events are not credible if relatively simple controls are applied. This paper presents an overview of the design, manufacture and testing of equipment to remove the estimated 15 tons of fire damaged fuel and isotopes from the Pile 1 reactor. The paper also discusses recently conducted characterization activities which have allowed for a refined waste estimate and conditioning strategy. These data and an innovative approach have resulted in a significant reduction in the estimated project cost and schedule. (authors)

  11. Thermal Conductivity of Rubble Piles

    NASA Astrophysics Data System (ADS)

    Luan, Jing; Goldreich, Peter

    2015-11-01

    Rubble piles are a common feature of solar system bodies. They are composed of monolithic elements of ice or rock bound by gravity. Voids occupy a significant fraction of the volume of a rubble pile. They can exist up to pressure P≈ {ε }Yμ , where {ε }Y is the monolithic material's yield strain and μ its rigidity. At low P, contacts between neighboring elements are confined to a small fraction of their surface areas. As a result, the effective thermal conductivity of a rubble pile, {k}{con}≈ k{(P/({ε }Yμ ))}1/2, can be orders of magnitude smaller than the thermal conductivity of its monolithic elements, k. In a fluid-free environment, only radiation can transfer energy across voids. It contributes an additional component, {k}{rad}=16{\\ell }σ {T}3/3, to the total effective conductivity, {k}{eff}={k}{con}+{k}{rad}. Here ℓ, the inverse of the opacity per unit volume, is of the order of the size of the elements, and voids. An important distinction between {k}{con} and {k}{rad} is that the former is independent of the size of the elements, whereas the latter is proportional to it. Our expression for {k}{eff} provides a good fit to the depth dependence of thermal conductivity in the top 140 cm of the lunar regolith. It also offers a good starting point for detailed modeling of thermal inertias for asteroids and satellites. Measurement of the response of surface temperature to variable insolation is a valuable diagnostic of a regolith. There is an opportunity for careful experiments under controlled laboratory conditions to test models of thermal conductivity such as the one we outline.

  12. Cutting Edge: Engineering Active IKKβ in T Cells Drives Tumor Rejection.

    PubMed

    Evaristo, César; Spranger, Stefani; Barnes, Sarah E; Miller, Michelle L; Molinero, Luciana L; Locke, Frederick L; Gajewski, Thomas F; Alegre, Maria-Luisa

    2016-04-01

    Acquired dysfunction of tumor-reactive T cells is one mechanism by which tumors can evade the immune system. Identifying and correcting pathways that contribute to such dysfunction should enable novel anticancer therapy design. During cancer growth, T cells show reduced NF-κB activity, which is required for tumor rejection. Impaired T cell-intrinsic NF-κB may create a vicious cycle conducive to tumor progression and further T cell dysfunction. We hypothesized that forcing T cell-intrinsic NF-κB activation might break this cycle and induce tumor elimination. NF-κB was activated in T cells by inducing the expression of a constitutively active form of the upstream activator IκB kinase β (IKKβ). T cell-restricted constitutively active IKKβ augmented the frequency of functional tumor-specific CD8(+) T cells and improved tumor control. Transfer of constitutively active IKKβ-transduced T cells also boosted endogenous T cell responses that controlled pre-established tumors. Our results demonstrate that driving T cell-intrinsic NF-κB can result in tumor control, thus identifying a pathway with potential clinical applicability. PMID:26903482

  13. 29 CFR 1926.603 - Pile driving equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the head block. (5) A blocking device, capable of safely supporting the weight of the hammer, shall be... hammer. (6) Guards shall be provided across the top of the head block to prevent the cable from jumping... with an adequate length of at least 1/4-inch diameter chain or cable to prevent whipping in the...

  14. 29 CFR 1926.603 - Pile driving equipment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... American Society of Mechanical Engineers, Power Boilers (section I). (2) All pressure vessels which are a... guardrails. (9) Steam hose leading to a steam hammer or jet pipe shall be securely attached to the hammer... required for steam lines. (10) Safety chains, or equivalent means, shall be provided for each...

  15. Direct activation of the Mauthner cell by electric field pulses drives ultrarapid escape responses.

    PubMed

    Tabor, Kathryn M; Bergeron, Sadie A; Horstick, Eric J; Jordan, Diana C; Aho, Vilma; Porkka-Heiskanen, Tarja; Haspel, Gal; Burgess, Harold A

    2014-08-15

    Rapid escape swims in fish are initiated by the Mauthner cells, giant reticulospinal neurons with unique specializations for swift responses. The Mauthner cells directly activate motoneurons and facilitate predator detection by integrating acoustic, mechanosensory, and visual stimuli. In addition, larval fish show well-coordinated escape responses when exposed to electric field pulses (EFPs). Sensitization of the Mauthner cell by genetic overexpression of the voltage-gated sodium channel SCN5 increased EFP responsiveness, whereas Mauthner ablation with an engineered variant of nitroreductase with increased activity (epNTR) eliminated the response. The reaction time to EFPs is extremely short, with many responses initiated within 2 ms of the EFP. Large neurons, such as Mauthner cells, show heightened sensitivity to extracellular voltage gradients. We therefore tested whether the rapid response to EFPs was due to direct activation of the Mauthner cells, bypassing delays imposed by stimulus detection and transmission by sensory cells. Consistent with this, calcium imaging indicated that EFPs robustly activated the Mauthner cell but only rarely fired other reticulospinal neurons. Further supporting this idea, pharmacological blockade of synaptic transmission in zebrafish did not affect Mauthner cell activity in response to EFPs. Moreover, Mauthner cells transgenically expressing a tetrodotoxin (TTX)-resistant voltage-gated sodium channel retained responses to EFPs despite TTX suppression of action potentials in the rest of the brain. We propose that EFPs directly activate Mauthner cells because of their large size, thereby driving ultrarapid escape responses in fish. PMID:24848468

  16. Direct activation of the Mauthner cell by electric field pulses drives ultrarapid escape responses

    PubMed Central

    Tabor, Kathryn M.; Bergeron, Sadie A.; Horstick, Eric J.; Jordan, Diana C.; Aho, Vilma; Porkka-Heiskanen, Tarja; Haspel, Gal

    2014-01-01

    Rapid escape swims in fish are initiated by the Mauthner cells, giant reticulospinal neurons with unique specializations for swift responses. The Mauthner cells directly activate motoneurons and facilitate predator detection by integrating acoustic, mechanosensory, and visual stimuli. In addition, larval fish show well-coordinated escape responses when exposed to electric field pulses (EFPs). Sensitization of the Mauthner cell by genetic overexpression of the voltage-gated sodium channel SCN5 increased EFP responsiveness, whereas Mauthner ablation with an engineered variant of nitroreductase with increased activity (epNTR) eliminated the response. The reaction time to EFPs is extremely short, with many responses initiated within 2 ms of the EFP. Large neurons, such as Mauthner cells, show heightened sensitivity to extracellular voltage gradients. We therefore tested whether the rapid response to EFPs was due to direct activation of the Mauthner cells, bypassing delays imposed by stimulus detection and transmission by sensory cells. Consistent with this, calcium imaging indicated that EFPs robustly activated the Mauthner cell but only rarely fired other reticulospinal neurons. Further supporting this idea, pharmacological blockade of synaptic transmission in zebrafish did not affect Mauthner cell activity in response to EFPs. Moreover, Mauthner cells transgenically expressing a tetrodotoxin (TTX)-resistant voltage-gated sodium channel retained responses to EFPs despite TTX suppression of action potentials in the rest of the brain. We propose that EFPs directly activate Mauthner cells because of their large size, thereby driving ultrarapid escape responses in fish. PMID:24848468

  17. Piling-jacket system and method

    SciTech Connect

    Sutton, J.S.

    1988-08-16

    A piling-jacket system is described including an elongated, hollow, piling jacket of flexible material having a top end and a bottom end for receiving grout therein and retaining the grout during the curing thereof for forming a concrete column therewith, the piling-jacket system comprising: a filling-port means located on the side of the piling jacket intermediate the top and bottom ends thereof, the filling-port means including an open port in the flexible-material jacket, a flap of flexible material mounted adjacent the open port on an interior surface of the piling jacket, and a flexible flap cord attached to the flap at an outer end portion thereof and extending through a cord hole defined by the flexible piling jacket to the exterior thereof; whereby a concrete-supply hose can be inserted through the open port thereby holding the flap away from the open port through which wet concrete can be pumped into the interior of the piling jacket and thereafter, once a top surface of the wet concrete is above the open port, the flexible concrete-supply hose can be pulled out of the open port so as to allow the flap to close the open port, and the flap cord can be pulled outwardly to positively pull the flap over the open port and thereby preventing wet concrete on the interior of the piling jacket from passing through the open port to the exterior thereof.

  18. Antibiotic Binding Drives Catalytic Activation of Aminoglycoside Kinase APH(2″)-Ia.

    PubMed

    Caldwell, Shane J; Huang, Yue; Berghuis, Albert M

    2016-06-01

    APH(2″)-Ia is a widely disseminated resistance factor frequently found in clinical isolates of Staphylococcus aureus and pathogenic enterococci, where it is constitutively expressed. APH(2″)-Ia confers high-level resistance to gentamicin and related aminoglycosides through phosphorylation of the antibiotic using guanosine triphosphate (GTP) as phosphate donor. We have determined crystal structures of the APH(2″)-Ia in complex with GTP analogs, guanosine diphosphate, and aminoglycosides. These structures collectively demonstrate that aminoglycoside binding to the GTP-bound kinase drives conformational changes that bring distant regions of the protein into contact. These changes in turn drive a switch of the triphosphate cofactor from an inactive, stabilized conformation to a catalytically competent active conformation. This switch has not been previously reported for antibiotic kinases or for the structurally related eukaryotic protein kinases. This catalytic triphosphate switch presents a means by which the enzyme can curtail wasteful hydrolysis of GTP in the absence of aminoglycosides, providing an evolutionary advantage to this enzyme. PMID:27161980

  19. Physiological investigation of automobile driver's activation index using simulated monotonous driving.

    PubMed

    Yamakoshi, T; Yamakoshi, K; Tanaka, S; Nogawa, M; Kusakabe, M; Kusumi, M; Tanida, K

    2004-01-01

    Monotonous automobile operation in our daily life may cause the lowering of what might be termed an activation state of the human body, resulting in an increased risk of an accident. We therefore propose to create a more suitable environment in-car so as to allow active operation of the vehicle, hopefully thus avoiding potentially dangerous situations during driving. In order to develop such an activation method as a final goal, we have firstly focused on the acquisition of physiological variables, including cardiovascular parameters, during presentation to the driver of a monotonous screen image, simulating autonomous travel of constant-speed on a motorway. Subsequently, we investigated the derivation of a driver's activation index. During the screen image presentation, a momentary electrical stimulation of about 1 second duration was involuntarily applied to a subject's shoulder to obtain a physiological response. We have successfully monitored various physiological variables during the image presentation, and results suggest that a peculiar pattern in the beat-by-beat change of blood pressure in response to the involuntary stimulus may be an appropriate, and feasible, index relevant to activation state. PMID:17270774

  20. SATB1 OVEREXPRESSION DRIVES TUMOR-PROMOTING ACTIVITIES IN CANCER-ASSOCIATED DENDRITIC CELLS

    PubMed Central

    Tesone, Amelia J.; Rutkowski, Melanie R.; Brencicova, Eva; Svoronos, Nikolaos; Perales-Puchalt, Alfredo; Stephen, Tom L.; Allegrezza, Michael J.; Payne, Kyle K.; Nguyen, Jenny M.; Wickramasinghe, Jayamanna; Tchou, Julia; Borowsky, Mark E.; Rabinovich, Gabriel A.; Kossenkov, Andrew V.; Conejo-Garcia, Jose R.

    2016-01-01

    SUMMARY Special AT-rich sequence-binding protein-1 (Satb1) governs genome-wide transcriptional programs. Using a conditional knockout mouse, we find that Satb1 is required for normal differentiation of conventional dendritic cells (DCs). Furthermore, Satb1 governs the differentiation of inflammatory DCs by regulating MHC-II expression through Notch1 signaling. Mechanistically, Satb1 binds to the Notch1 promoter, activating Notch expression and driving RBPJ occupancy of the H2-Ab1 promoter, which activates MHC-II transcription. However, tumor-driven, unremitting expression of Satb1 in activated Zbtb46+ inflammatory DCs that infiltrate ovarian tumors results in an immunosuppressive phenotype characterized by increased secretion of tumor-promoting Galectin-1 and IL-6. In vivo silencing of Satb1 in tumor-associated DCs reverses their tumorigenic activity and boosts protective immunity. Therefore, dynamic fluctuations in Satb1 expression govern the generation and immunostimulatory activity of steady-state and inflammatory DCs, but continuous Satb1 overexpression in differentiated DCs converts them into tolerogenic/pro-inflammatory cells that contribute to malignant progression. PMID:26876172

  1. Satb1 Overexpression Drives Tumor-Promoting Activities in Cancer-Associated Dendritic Cells.

    PubMed

    Tesone, Amelia J; Rutkowski, Melanie R; Brencicova, Eva; Svoronos, Nikolaos; Perales-Puchalt, Alfredo; Stephen, Tom L; Allegrezza, Michael J; Payne, Kyle K; Nguyen, Jenny M; Wickramasinghe, Jayamanna; Tchou, Julia; Borowsky, Mark E; Rabinovich, Gabriel A; Kossenkov, Andrew V; Conejo-Garcia, Jose R

    2016-02-23

    Special AT-rich sequence-binding protein 1 (Satb1) governs genome-wide transcriptional programs. Using a conditional knockout mouse, we find that Satb1 is required for normal differentiation of conventional dendritic cells (DCs). Furthermore, Satb1 governs the differentiation of inflammatory DCs by regulating major histocompatibility complex class II (MHC II) expression through Notch1 signaling. Mechanistically, Satb1 binds to the Notch1 promoter, activating Notch expression and driving RBPJ occupancy of the H2-Ab1 promoter, which activates MHC II transcription. However, tumor-driven, unremitting expression of Satb1 in activated Zbtb46(+) inflammatory DCs that infiltrate ovarian tumors results in an immunosuppressive phenotype characterized by increased secretion of tumor-promoting Galectin-1 and IL-6. In vivo silencing of Satb1 in tumor-associated DCs reverses their tumorigenic activity and boosts protective immunity. Therefore, dynamic fluctuations in Satb1 expression govern the generation and immunostimulatory activity of steady-state and inflammatory DCs, but continuous Satb1 overexpression in differentiated DCs converts them into tolerogenic/pro-inflammatory cells that contribute to malignant progression. PMID:26876172

  2. BAS-drive trait modulates dorsomedial striatum activity during reward response-outcome associations.

    PubMed

    Costumero, Víctor; Barrós-Loscertales, Alfonso; Fuentes, Paola; Rosell-Negre, Patricia; Bustamante, Juan Carlos; Ávila, César

    2016-09-01

    According to the Reinforcement Sensitivity Theory, behavioral studies have found that individuals with stronger reward sensitivity easily detect cues of reward and establish faster associations between instrumental responses and reward. Neuroimaging studies have shown that processing anticipatory cues of reward is accompanied by stronger ventral striatum activity in individuals with stronger reward sensitivity. Even though establishing response-outcome contingencies has been consistently associated with dorsal striatum, individual differences in this process are poorly understood. Here, we aimed to study the relation between reward sensitivity and brain activity while processing response-reward contingencies. Forty-five participants completed the BIS/BAS questionnaire and performed a gambling task paradigm in which they received monetary rewards or punishments. Overall, our task replicated previous results that have related processing high reward outcomes with activation of striatum and medial frontal areas, whereas processing high punishment outcomes was associated with stronger activity in insula and middle cingulate. As expected, the individual differences in the activity of dorsomedial striatum correlated positively with BAS-Drive. Our results agree with previous studies that have related the dorsomedial striatum with instrumental performance, and suggest that the individual differences in this area may form part of the neural substrate responsible for modulating instrumental conditioning by reward sensitivity. PMID:26489979

  3. An in-pile testing program to study the performance characteristics of coated particle fuels

    SciTech Connect

    Wright, S.A. )

    1993-01-15

    Sandia National Laboratories is actively involved in testing coated particle nuclear fuels for the Space Nuclear Thermal Propulsion (SNTP) program managed by Phillips Laboratory. The testing program integrates the results of numerous in-pile and out-of-pile tests with modeling efforts to qualify fuel and fuel elements for the SNTP program. This paper briefly describes the capabilities of the Annular Core Research Reactor (in which the experiments are performed), the major in-pile tests, and the models used to determine the performance characteristics of the fuel and fuel elements.

  4. An in-pile testing program to study the performance characteristics of coated particle fuels

    SciTech Connect

    Wright, S.A.

    1992-01-01

    Sandia National Laboratories is actively involved in testing coated particle nuclear fuels for the Space Nuclear Thermal Propulsion (SNTP) program managed by Phillips Laboratory. The testing program integrates the results of numerous in-pile and out-of-pile tests with modeling efforts to qualify fuel and fuel elements for the SNTP program. This paper briefly describes the capabilities of the Annular Core Research Reactor (in which the experiments are performed), the major in-pile tests, and the models used to determine the performance characteristics of the fuel and fuel elements. 6 refs.

  5. Adult activity and temperature preference drives region-wide damselfly (Zygoptera) distributions under a warming climate

    PubMed Central

    Corser, Jeffrey D.; White, Erin L.; Schlesinger, Matthew D.

    2015-01-01

    We analysed a recently completed statewide odonate Atlas using multivariate linear models. Within a phylogenetically explicit framework, we developed a suite of data-derived traits to assess the mechanistic distributional drivers of 59 species of damselflies in New York State (NYS). We found that length of the flight season (adult breeding activity period) mediated by thermal preference drives regional distributions at broad (105 km2) scales. Species that had longer adult flight periods, in conjunction with longer growing seasons, had significantly wider distributions. These intrinsic traits shape species' responses to changing climates and the mechanisms behind such range shifts are fitness-based metapopulation processes that adjust phenology to the prevailing habitat and climate regime through a photoperiod filter. PMID:25878048

  6. Impact of awareness drives and community-based active tuberculosis case finding in Odisha, India.

    PubMed

    Parija, D; Patra, T K; Kumar, A M V; Swain, B K; Satyanarayana, S; Sreenivas, A; Chadha, V K; Moonan, P K; Oeltmann, J E

    2014-09-01

    India's Revised National Tuberculosis Control programme employs passive case detection. The new sputum smear-positive case detection rate is less than 70% in Odisha State. During April-June 2012, active case finding (ACF) was conducted through awareness drives and field-based tuberculosis (TB) screening in select communities with the lowest case detection rates. During the campaign, 240 sputum smear-positive TB cases were detected. The number of smear-positive cases detected increased by 11% relative to April-June 2011 in intervention communities compared to an 0.8% increase in non-intervention communities. ACF brought TB services closer to the community and increased TB case detection. PMID:25189560

  7. Activation of Rho-kinase in the brainstem enhances sympathetic drive in mice with heart failure.

    PubMed

    Ito, Koji; Kimura, Yoshikuni; Hirooka, Yoshitaka; Sagara, Yoji; Sunagawa, Kenji

    2008-11-01

    Rho-kinase is involved in the pathogenesis of hypertension and left ventricular remodelling after myocardial infarction (MI). In an earlier study, we had demonstrated that Rho-kinase in the brainstem contributes to hypertensive mechanisms via the sympathetic nervous system; however, it is not known whether Rho-kinase in the brainstem also contributes to sympathetic nerve activation after MI. Male Institute of Cancer Research mice (8-10 weeks old) were used for the study. Two days before coronary artery occlusion (MI group), the left ventricular function was estimated by echocardiography. Following this, Y-27632 (0.5 mM, 0.25 microL/h), a specific Rho-kinase inhibitor, or a vehicle was intracisternally infused in the mice using an osmotic mini-pump. Nine days after coronary artery occlusion, we evaluated the 24-hour urinary norepinephrine excretion (U-NE) as a marker of sympathetic nerve activity. Ten days after coronary artery occlusion, we measured organ weight and evaluated Rho-kinase activity in the brainstem by measuring the amount of phosphorylated ezrin/radixin/moesin proteins, one of the substrates of Rho-kinase. The control group underwent a sham operation. Rho-kinase activity, U-NE, and lungs and liver weight were significantly greater in the MI group compared with the control group. Left ventricular size increased and percent fractional shortening decreased in the MI group compared with the control group. Y-27632 significantly decreased Rho-kinase activity and attenuated the increase in U-NE after MI. These results demonstrate that Rho-kinase is activated in the brainstem after MI and that the activation of this pathway is involved in the resulting enhanced sympathetic drive. PMID:18762460

  8. Alternaria-derived serine protease activity drives IL-33–mediated asthma exacerbations

    PubMed Central

    Snelgrove, Robert J.; Gregory, Lisa G.; Peiró, Teresa; Akthar, Samia; Campbell, Gaynor A.; Walker, Simone A.; Lloyd, Clare M.

    2014-01-01

    Background The fungal allergen Alternaria alternata is implicated in severe asthma and rapid onset life-threatening exacerbations of disease. However, the mechanisms that underlie this severe pathogenicity remain unclear. Objective We sought to investigate the mechanism whereby Alternaria was capable of initiating severe, rapid onset allergic inflammation. Methods IL-33 levels were quantified in wild-type and ST2−/− mice that lacked the IL-33 receptor given inhaled house dust mite, cat dander, or Alternaria, and the effect of inhibiting allergen-specific protease activities on IL-33 levels was assessed. An exacerbation model of allergic airway disease was established whereby mice were sensitized with house dust mite before subsequently being challenged with Alternaria (with or without serine protease activity), and inflammation, remodeling, and lung function assessed 24 hours later. Results Alternaria, but not other common aeroallergens, possessed intrinsic serine protease activity that elicited the rapid release of IL-33 into the airways of mice through a mechanism that was dependent upon the activation of protease activated receptor-2 and adenosine triphosphate signaling. The unique capacity of Alternaria to drive this early IL-33 release resulted in a greater pulmonary inflammation by 24 hours after challenge relative to the common aeroallergen house dust mite. Furthermore, this Alternaria serine protease–IL-33 axis triggered a rapid, augmented inflammation, mucus release, and loss of lung function in our exacerbation model. Conclusion Alternaria-specific serine protease activity causes rapid IL-33 release, which underlies the development of a robust TH2 inflammation and exacerbation of allergic airway disease. PMID:24636086

  9. EEG-based decoding of error-related brain activity in a real-world driving task

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Chavarriaga, R.; Khaliliardali, Z.; Gheorghe, L.; Iturrate, I.; Millán, J. d. R.

    2015-12-01

    Objectives. Recent studies have started to explore the implementation of brain-computer interfaces (BCI) as part of driving assistant systems. The current study presents an EEG-based BCI that decodes error-related brain activity. Such information can be used, e.g., to predict driver’s intended turning direction before reaching road intersections. Approach. We executed experiments in a car simulator (N = 22) and a real car (N = 8). While subject was driving, a directional cue was shown before reaching an intersection, and we classified the presence or not of an error-related potentials from EEG to infer whether the cued direction coincided with the subject’s intention. In this protocol, the directional cue can correspond to an estimation of the driving direction provided by a driving assistance system. We analyzed ERPs elicited during normal driving and evaluated the classification performance in both offline and online tests. Results. An average classification accuracy of 0.698 ± 0.065 was obtained in offline experiments in the car simulator, while tests in the real car yielded a performance of 0.682 ± 0.059. The results were significantly higher than chance level for all cases. Online experiments led to equivalent performances in both simulated and real car driving experiments. These results support the feasibility of decoding these signals to help estimating whether the driver’s intention coincides with the advice provided by the driving assistant in a real car. Significance. The study demonstrates a BCI system in real-world driving, extending the work from previous simulated studies. As far as we know, this is the first online study in real car decoding driver’s error-related brain activity. Given the encouraging results, the paradigm could be further improved by using more sophisticated machine learning approaches and possibly be combined with applications in intelligent vehicles.

  10. Lesbian blood drives as community-building activism in the 1980s.

    PubMed

    Hutchison, Beth

    2015-01-01

    As gay men began voluntarily withdrawing from blood donation in the early 1980s, lesbians in community with gay men in several U.S. cities organized drives to replenish the blood supply. These drives were sometimes the continuation of previously established drives by gay-lesbian organizations or faith communities, sometimes new initiatives in response to HIV/AIDS. However, after the initial publicity, mention of lesbian blood drives in print is both scarce and brief. Focusing on drives organized from 1983 to 1992 by a group known as San Diego Blood Sisters, this article is an initial step in documenting lesbian blood drives to inform and enrich conversations about histories of responses to HIV/AIDS, theoretical discussions of how community connections in the lesbian, gay, bisexual, transgender, and queer spectrum are enacted and understood, and emerging research on intersections of gender and sexuality as they are expressed through blood donorship. PMID:25575331

  11. Nonlinear Seismic Response Of Single Piles

    SciTech Connect

    Cairo, R.; Conte, E.; Dente, G.

    2008-07-08

    In this paper, a method is proposed to analyse the seismic response of single piles under nonlinear soil condition. It is based on the Winkler foundation model formulated in the time domain, which makes use of p-y curves described by the Ramberg-Osgood relationship. The analyses are performed referring to a pile embedded in two-layer soil profiles with different sharp stiffness contrast. Italian seismic records are used as input motion. The calculated bending moments in the pile are compared to those obtained using other theoretical solutions.

  12. Environmental assessment of creosote-treated pilings in the marine environment

    SciTech Connect

    Butala, J.H.; Webb, D.A.; Jop, K.M.; Putt, A.E.

    1995-12-31

    A comprehensive ecological risk assessment was conducted to evaluate the environmental impact of creosote-treated pilings in the marine environment at Moss Landing Harbor, Moss Landing, California. Four areas of investigation comprising the risk assessment were (1) evaluation of environmental conditions around existing creosote-treated pilings (2) investigating effects related to restoration of pilings (3) assessing creosote migration into surrounding environment, one year after pile-driving and (4) confirmation of creosote toxicity in laboratory studies. Biological and chemical evaluation of the impact of creosote-treated pilings was conducted on surface sheen, water column and sediment samples collected at Moss Landing Harbor. Water samples (surface sheen, water column and sediment pore water) were evaluated using short-term chronic exposures with Mysidopsis bahia, while bulk sediment samples were evaluated with 10-day sediment toxicity tests with Ampelisca abdita. Samples of surface, column water and sediment were analyzed for the constituents of creosote by GC mass spectrometry. In addition, a sample of neat material used to preserve treated pilings represented a reference for the polyaromatic hydrocarbons. Verification of organism response and analyses of field collected samples was performed by conducting 10-day A. abdita sediment and 7-day M. bahia elutriate exposures with creosote applied to clean sediment collected at Moss Landing, Evaluations were also performed to determine the effects of photoinduced toxicity on test organisms exposed to PAHs. The biological and analytical results of the field and laboratory exposures are being used to evaluate and determine risk of creosote-treated pilings on the marine environment.

  13. Wind from the black-hole accretion disk driving a molecular outflow in an active galaxy

    NASA Astrophysics Data System (ADS)

    Tombesi, F.; Meléndez, M.; Veilleux, S.; Reeves, J. N.; González-Alfonso, E.; Reynolds, C. S.

    2015-03-01

    Powerful winds driven by active galactic nuclei are often thought to affect the evolution of both supermassive black holes and their host galaxies, quenching star formation and explaining the close relationship between black holes and galaxies. Recent observations of large-scale molecular outflows in ultraluminous infrared galaxies support this quasar-feedback idea, because they directly trace the gas from which stars form. Theoretical models suggest that these outflows originate as energy-conserving flows driven by fast accretion-disk winds. Proposed connections between large-scale molecular outflows and accretion-disk activity in ultraluminous galaxies were incomplete because no accretion-disk wind had been detected. Conversely, studies of powerful accretion-disk winds have until now focused only on X-ray observations of local Seyfert galaxies and a few higher-redshift quasars. Here we report observations of a powerful accretion-disk wind with a mildly relativistic velocity (a quarter that of light) in the X-ray spectrum of IRAS F11119+3257, a nearby (redshift 0.189) optically classified type 1 ultraluminous infrared galaxy hosting a powerful molecular outflow. The active galactic nucleus is responsible for about 80 per cent of the emission, with a quasar-like luminosity of 1.5 × 1046 ergs per second. The energetics of these two types of wide-angle outflows is consistent with the energy-conserving mechanism that is the basis of the quasar feedback in active galactic nuclei that lack powerful radio jets (such jets are an alternative way to drive molecular outflows).

  14. Wind from the black-hole accretion disk driving a molecular outflow in an active galaxy.

    PubMed

    Tombesi, F; Meléndez, M; Veilleux, S; Reeves, J N; González-Alfonso, E; Reynolds, C S

    2015-03-26

    Powerful winds driven by active galactic nuclei are often thought to affect the evolution of both supermassive black holes and their host galaxies, quenching star formation and explaining the close relationship between black holes and galaxies. Recent observations of large-scale molecular outflows in ultraluminous infrared galaxies support this quasar-feedback idea, because they directly trace the gas from which stars form. Theoretical models suggest that these outflows originate as energy-conserving flows driven by fast accretion-disk winds. Proposed connections between large-scale molecular outflows and accretion-disk activity in ultraluminous galaxies were incomplete because no accretion-disk wind had been detected. Conversely, studies of powerful accretion-disk winds have until now focused only on X-ray observations of local Seyfert galaxies and a few higher-redshift quasars. Here we report observations of a powerful accretion-disk wind with a mildly relativistic velocity (a quarter that of light) in the X-ray spectrum of IRAS F11119+3257, a nearby (redshift 0.189) optically classified type 1 ultraluminous infrared galaxy hosting a powerful molecular outflow. The active galactic nucleus is responsible for about 80 per cent of the emission, with a quasar-like luminosity of 1.5 × 10(46) ergs per second. The energetics of these two types of wide-angle outflows is consistent with the energy-conserving mechanism that is the basis of the quasar feedback in active galactic nuclei that lack powerful radio jets (such jets are an alternative way to drive molecular outflows). PMID:25810204

  15. Active Prompting to Decrease Cell Phone Use and Increase Seat Belt Use while Driving

    ERIC Educational Resources Information Center

    Clayton, Michael; Helms, Bridgett; Simpson, Cathy

    2006-01-01

    Automobile crashes are the leading cause of death for those aged 3 to 33, with 43,005 (118 per day) Americans killed in 2002 alone. Seat belt use reduces the risk of serious injury in an accident, and refraining from using a cell phone while driving reduces the risk of an accident. Cell phone use while driving increases accident rates, and leads…

  16. High Temperature Thermocouples For In-pile Applications

    SciTech Connect

    J. L. Rempe; S. C. Wilkins

    2005-10-01

    Traditional methods for measuring temperature in-pile degrade at temperatures above 1080 degrees C. Hence, a project has been initiated to explore the use of specialized thermocouples that are composed of materials that are able to withstand higher temperature, in-pile test conditions. Results from efforts to develop, fabricate and evaluate the performance of these specialized thermocouples are reported in this paper. Candidate materials were evaluated for their ability to withstand irradiation, to resit material interactions and to remain ductile at high temperatures. In addition, candidate thermocouples were evaluated based on their resolution over the temperature ranges of interest. Results from these evaluations are reported, and additional on-going development activities are summarized.

  17. β-Arrestin-1 Drives Endothelin-1–Mediated Podocyte Activation and Sustains Renal Injury

    PubMed Central

    Buelli, Simona; Rosanò, Laura; Gagliardini, Elena; Corna, Daniela; Longaretti, Lorena; Pezzotta, Anna; Perico, Luca; Conti, Sara; Rizzo, Paola; Novelli, Rubina; Morigi, Marina; Zoja, Carlamaria; Remuzzi, Giuseppe; Bagnato, Anna

    2014-01-01

    Activation of endothelin-A receptor (ETAR) by endothelin-1 (ET-1) drives epithelial-to-mesenchymal transition in ovarian tumor cells through β-arrestin signaling. Here, we investigated whether this pathogenetic pathway could affect podocyte phenotype in proliferative glomerular disorders. In cultured mouse podocytes, ET-1 caused loss of the podocyte differentiation marker synaptopodin and acquisition of the mesenchymal marker α-smooth muscle actin. ET-1 promoted podocyte migration via ETAR activation and increased β-arrestin-1 expression. Activated ETAR recruited β-arrestin-1 to form a trimeric complex with Src leading to epithelial growth factor receptor (EGFR) transactivation and β-catenin phosphorylation, which promoted gene transcription of Snail. Increased Snail expression fostered ET-1–induced migration as confirmed by Snail knockdown experiments. Silencing of β-arrestin-1 prevented podocyte phenotypic changes and motility and inhibited ETAR-driven signaling. In vitro findings were confirmed in doxorubicin (Adriamycin)-induced nephropathy. Mice receiving Adriamycin developed renal injury with loss of podocytes and hyperplastic lesion formation; β-arrestin-1 expression increased in visceral podocytes and in podocytes entrapped in pseudo-crescents. Administration of the selective ETAR antagonist sitaxsentan prevented podocyte loss, formation of the hyperplastic lesions, and normalized expression of glomerular β-arrestin-1 and Snail. Increased β-arrestin-1 levels in podocytes retrieved from crescents of patients with proliferative glomerulopathies confirmed the translational relevance of these findings and suggest the therapeutic potential of ETAR antagonism for a group of diseases still needing a specific treatment. PMID:24371298

  18. 116. Photocopied August 1978. NEW INTERLOCKING STEEL SHEET PILING AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    116. Photocopied August 1978. NEW INTERLOCKING STEEL SHEET PILING AT PENSTOCK 52 IN THE FALL OF 1926. THE PILES FOR SUPPORTING THE HORIZONTAL ELEMENTS OF THE NEW FOREBAY APRON ARE IN PLACE BETWEEN THE NEW SHEET PILING AND THE FOREBAY WALL. VISIBLE BEYOND THE NEW SHEET PILING IS THE TIMBER SHEET PILING DRIVEN IN 1903 BY VON SCHON TO PREVENT WASHOUTS. (1006) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

  19. 75 FR 38783 - Takes of Marine Mammals Incidental to Specified Activities; Manette Bridge Replacement in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-06

    ... the proposed IHA (75 FR 13502, March 22, 2010) and in the WSDOT's IHA application. No changes have... Register on March 22, 2010 (75 FR 13502). During the 30-day comment period, NMFS received a letter from the... activities, and ramp-up for pile driving) as described in NMFS' March 22, 2010 (75 FR 13502), notice of...

  20. Grouting of uranium mill tailings piles

    SciTech Connect

    Boegly, W.J. Jr.; Tamura, T.; Williams, J.D.

    1984-03-01

    A program of remedial action was initiated for a number of inactive uranium mill tailings piles. These piles result from mining and processing of uranium ores to meet the nation's defense and nuclear power needs and represent a potential hazard to health and the environment. Possible remedial actions include the application of covers to reduce radon emissions and airborne transport of the tailings, liners to prevent groundwater contamination by leachates from the piles, physical or chemical stabilization of the tailings, or moving the piles to remote locations. Conventional installation of liners would require excavation of the piles to emplace the liner; however, utilization of grouting techniques, such as those used in civil engineering to stabilize soils, might be a potential method of producing a liner without excavation. Laboratory studies on groutability of uranium mill tailings were conducted using samples from three abandoned piles and employing a number of particulate and chemical grouts. These studies indicate that it is possible to alter the permeability of the tailings from ambient values of 10/sup -3/ cm/s to values approaching 10/sup -7/ cm/s using silicate grouts and to 10/sup -8/ cm/s using acrylamide and acrylate grouts. An evaluation of grouting techniques, equipment required, and costs associated with grouting were also conducted and are presented. 10 references, 1 table.

  1. The role of transient ion foreshock phenomena in driving Pc5 ULF wave activity

    NASA Astrophysics Data System (ADS)

    Hartinger, M. D.; Turner, D. L.; Plaschke, F.; Angelopoulos, V.; Singer, H.

    2013-01-01

    The ion foreshock is a source of energy for magnetospheric ULF waves, but it is usually only considered effective at driving ULF waves with frequencies above the Pc5 (2-7 mHz) range. We present observations for an 8 h high speed solar wind interval on 14 July 2008 during which three distinct types of transient ion foreshock phenomena (TIFP) were observed just upstream of the dayside bow shock. We demonstrate that TIFP generate global magnetospheric Pc5 ULF waves with amplitudes as large as 10 mV/m in the electric field and 10 nT in the magnetic field. We characterize the magnetospheric ULF response to several different TIFP that occur during this interval, including the first report of the ULF response to a foreshock bubble. Using a novel spacecraft configuration, we find that the local time with the highest Pc5 wave amplitude is closely related to the location of the ion foreshock. Statistical studies of Pc5 ULF wave activity, other case studies of ULF waves driven by processes in the ion foreshock, and recent theoretical and simulation work on TIFP place these results in context: TIFP are an important energy source for Pc5 ULF waves in the magnetosphere.

  2. The role of transient ion foreshock phenomena in driving Pc5 ULF wave activity

    NASA Astrophysics Data System (ADS)

    Hartinger, M.; Turner, D. L.; Plaschke, F.; Angelopoulos, V.; Singer, H. J.

    2013-05-01

    The ion foreshock is a source of energy for magnetospheric Ultra Low Frequency (ULF) waves, but it is usually only considered effective at driving ULF waves with frequencies above the Pc5 (2-7 mHz) range. We present observations for an eight hour high speed solar wind interval on 14 July 2008 during which three distinct types of transient ion foreshock phenomena (TIFP) were observed just upstream of the dayside bow shock. We demonstrate that TIFP generate global magnetospheric Pc5 ULF waves with amplitudes as large as 10 mV/m in the electric field and 10 nT in the magnetic field. We characterize the magnetospheric ULF response to several different TIFP that occur during this interval, including the first report of the ULF response to a Foreshock Bubble (FB). Using a fortuitous spacecraft configuration, we find that the local time with the highest Pc5 wave amplitude is closely related to the location of the ion foreshock. Statistical studies of Pc5 ULF wave activity, other case studies of ULF waves driven by processes in the ion foreshock, and recent theoretical and simulation work on TIFP place these results in context: TIFP are an important energy source for Pc5 ULF waves in the magnetosphere.

  3. Can Active Navigation Be as Good as Driving? A Comparison of Spatial Memory in Drivers and Backseat Drivers

    ERIC Educational Resources Information Center

    von Stulpnagel, Rul; Steffens, Melanie C.

    2012-01-01

    When driving a vehicle, either the driver or a passenger (henceforth: backseat driver) may be responsible for navigation. Research on active navigation, primarily addressed in virtual environments, suggests that controlling navigation is more central for spatial learning than controlling movement. To test this assumption in a real-world scenario,…

  4. Radiocarbon from Pile Graphite; Chemical Methods for Its Concentrations

    DOE R&D Accomplishments Database

    Arnold, J. R.; Libby, W. F.

    1946-10-10

    Samples of pile graphite, irradiated in a test-hole at Hanford for 15 months, have been assayed for radioactive C{sup 14} yielding 0.38 ± 0.04 microcuries per gram. At this level of activity, the pile graphite contains very valuable amounts of C{sup14}. The relation between the above assay and the probable average assay of pile graphite is discussed, and it is concluded that the latter is almost certainly above 0.3 microcuries/gram. Controlled oxidation of this graphite, either with oxygen at ~750ºC, or with chromic acid "cleaning solution" at room temperature, yields early fractions which are highly enriched in C{sup 14}. Concentrations of 5-fold with oxygen, and 50-fold with CrO{sub 3}, have been observed. The relation between the observed enrichment and the Wigner effect is discussed, and a mechanism accounting for the observations put forward. According to this, about 25% of the stable carbon atoms in the lattice have been displaced by Wigner effect, a large fraction of which have healed by migrating to crystal edges. All the C{sup 14} atoms have been displaced, and the same fraction of these migrate to the edges. The enrichment then results from surface oxidation, in the oxygen case. Predictions are made on the basis of this hypothesis. A technique of counting radioactive CO{sub 2} in the gas phase is described.

  5. Chestnut Ridge Borrow Area Waste Pile work plan

    SciTech Connect

    Johnson, R. )

    1991-08-01

    The US Department of Energy (DOE), through its contractor Martin Marietta Energy Systems, Inc., has constructed a storage facility, the Chestnut Ridge Borrow Area Waste Pile (CRBAWP), for mercury-contaminated soil excavated from the Oak Ridge Civic Center properties and the Oak Ridge Sewer Line Beltway. Excavation of the soil from the Civic Center began in September 1984 and was completed in early 1985. Similar soils from other areas of the city were added to the pile until 1987. Approximately 3000 yd{sup 3} are stored at the present time. An Interim Status RCRA permit was initially sought for this facility. Samples from the waste pile passed the Extraction Procedure Toxicity Test (EP Tox). The Tennessee Department of Health and Environment (now the Tennessee Department of Conservation-TDC) denied the permit based on their conclusion that the waste was not a RCRA-regulated waste. On September 25, 1990 the Toxicity Characteristic Leaching Procedure (TCLP) superseded the EP Tox test. TCLP tests are not proposed to satisfy a request by TDC and to make a final determination of the nature of the soils in order to close the CRBAWP as a solid waste disposal facility under Tennessee State rule 1200-1-7-.04. The objectives of this work are to summarize existing site information and detail actions necessary to sample and characterize soils from the waste pile as hazardous or nonhazardous per the Toxicity Characteristic Leaching Procedure (TCLP). Within the scope of this plan, a site investigation will be discussed; a field sampling plan will be described in terms of sampling locations, procedures, and quality assurance; and ancillary activities such as waste management, data management, and health and safety will be outlines. 15 refs., 7 figs., 2 tabs.

  6. 78 FR 9373 - Taking of Marine Mammals Incidental to Specified Activities; Construction at Orcas Island and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-08

    ... APE 400 King Kong (or equivalent) with a drive force of 361 tons. ] Sound Levels from Proposed... hollow steel piling. No sound level data is available for 13-inch timber and plastic- faced piles. Based... vibratory driving of 36'' steel piles will be 177 dB re 1 Pa (rms) at 10 m. While in-air sounds are...

  7. 75 FR 42691 - Small Takes of Marine Mammals Incidental to Specified Activities; Exploratorium Relocation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ..., respectively. Sound attenuation devices (e.g., wood block, bubble curtain) would be used during any impact... during impact pile driving of similar size piles proposed for use by the Exploratorium (Table 3). Bubble... likely an overestimate of sound levels produced by pile driving using a bubble curtain or wood cap....

  8. Lateral load tests on large pipe piles in coral

    SciTech Connect

    Vines, W.R.; Hong, I.S.

    1984-05-01

    Results are presented for lateral load tests on 36-, 48-, 80-, and 132-in. diameter pipe piles in 26- to 67-ft water depths at a port site in Saudi Arabia. Primary soil types at the site are crushed coral and sand, with layers of intact weak coral. Pile loads were measured with load cells, deflections were measured with potentiometers, and pile slopes were measured with a slope indicator. Pile top deflections and pile deflected shapes are reported at several load levels. Maximum test loads ranged from 72 to 559 kips, and maximum pile top deflections were from 3.6 to 55 inches. Comparison of test results to expectations of behavior based on state-of-the-practice analytical methods shows that the character of pile deflected shapes were predicted well, but that deflections were generally over-predicted in the analyses. Comparison of test pile and reaction pile deflected shapes shows secondary but significant differences.

  9. Crowd-Sourcing Management Activity Data to Drive GHG Emission Inventories in the Land Use Sector

    NASA Astrophysics Data System (ADS)

    Paustian, K.; Herrick, J.

    2015-12-01

    Greenhouse gas (GHG) emissions from the land use sector constitute the largest source category for many countries in Africa. Enhancing C sequestration and reducing GHG emissions on managed lands in Africa has to potential to attract C financing to support adoption of more sustainable land management practices that, in addition to GHG mitigation, can provide co-benefits of more productive and climate-resilient agroecosystems. However, robust systems to measure and monitor C sequestration/GHG reductions are currently a significant barrier to attracting more C financing to land use-related mitigation efforts.Anthropogenic GHG emissions are driven by a variety of environmental factors, including climate and soil attributes, as well as human-activities in the form of land use and management practices. GHG emission inventories typically use empirical or process-based models of emission rates that are driven by environmental and management variables. While a lack of field-based flux and C stock measurements are a limiting factor for GHG estimation, we argue that an even greater limitation may be availabiity of data on the management activities that influence flux rates, particularly in developing countries in Africa. In most developed countries there is a well-developed infrastructure of agricultural statistics and practice surveys that can be used to drive model-based GHG emission estimations. However, this infrastructure is largely lacking in developing countries in Africa. While some activity data (e.g. land cover change) can be derived from remote sensing, many key data (e.g., N fertilizer practices, residue management, manuring) require input from the farmers themselves. The explosive growth in cellular technology, even in many of the poorest parts of Africa, suggests the potential for a new crowd-sourcing approach and direct engagement with farmers to 'leap-frog' the land resource information model of developed countries. Among the many benefits of this approach

  10. Study of wear and galling in aircraft fuel pump drive shafts and gears using the surface layer activation technique

    NASA Astrophysics Data System (ADS)

    Gallmann, A.; Natter, B.; Molinari, M. A.

    1988-10-01

    The surface layer activation technique (SLA) has been applied to study galling and wear in moving parts of Boeing 747 engines. Radioactive 56Co was formed by the reaction 56Fe(p, n) 56Co in fuel pump drive shafts and gears, and their residual activities in these activated parts were measured in situ during routine inspections over more than one year. The study of the wear was done on shafts made of a new alloy and on gears having a new tooth geometry. Wear determined by SLA was corroborated by a profile measurement made when one of the pumps was disassembled. The study of the galling (with release of metallic fragments) of a drive shaft consisted in checking the condition of the critical zone of the splines with the SLA technique. The main originality of the present work is that for the first time such measurements were performed on engines in revenue service.

  11. Greater Activity in the Frontal Cortex on Left Curves: A Vector-Based fNIRS Study of Left and Right Curve Driving

    PubMed Central

    Oka, Noriyuki; Yoshino, Kayoko; Yamamoto, Kouji; Takahashi, Hideki; Li, Shuguang; Sugimachi, Toshiyuki; Nakano, Kimihiko; Suda, Yoshihiro; Kato, Toshinori

    2015-01-01

    Objectives In the brain, the mechanisms of attention to the left and the right are known to be different. It is possible that brain activity when driving also differs with different horizontal road alignments (left or right curves), but little is known about this. We found driver brain activity to be different when driving on left and right curves, in an experiment using a large-scale driving simulator and functional near-infrared spectroscopy (fNIRS). Research Design and Methods The participants were fifteen healthy adults. We created a course simulating an expressway, comprising straight line driving and gentle left and right curves, and monitored the participants under driving conditions, in which they drove at a constant speed of 100 km/h, and under non-driving conditions, in which they simply watched the screen (visual task). Changes in hemoglobin concentrations were monitored at 48 channels including the prefrontal cortex, the premotor cortex, the primary motor cortex and the parietal cortex. From orthogonal vectors of changes in deoxyhemoglobin and changes in oxyhemoglobin, we calculated changes in cerebral oxygen exchange, reflecting neural activity, and statistically compared the resulting values from the right and left curve sections. Results Under driving conditions, there were no sites where cerebral oxygen exchange increased significantly more during right curves than during left curves (p > 0.05), but cerebral oxygen exchange increased significantly more during left curves (p < 0.05) in the right premotor cortex, the right frontal eye field and the bilateral prefrontal cortex. Under non-driving conditions, increases were significantly greater during left curves (p < 0.05) only in the right frontal eye field. Conclusions Left curve driving was thus found to require more brain activity at multiple sites, suggesting that left curve driving may require more visual attention than right curve driving. The right frontal eye field was activated under both

  12. Comparative Analysis of Passenger Traffic Fleets in Asian Cities: Technology, Driving Activities, and Emission

    NASA Astrophysics Data System (ADS)

    KIM Oanh, N. T.; Huynh, H. V.; Saikawa, E.

    2015-12-01

    The road transport sector is the major emission source of toxic air pollutants and greenhouse gases (GHGs) in large Asian cities. This paper comparatively analyzed on-road passenger traffic fleets (cars, buses, taxis, motorcycles), using local data collected in cities of Bangkok (BKK), Kathmandu, Hanoi, Ho Chi Minh City (HCMC), and Yangon. Surveys were done in 2010-2014 to obtain information on vehicle technology, driving activities (speed, distance, number, and types of starts), traffic density, and fuel characteristics. Large shares of pre-Euro vehicles were still observed, especially for public buses. The most advanced technology was Euro4, which was observed in small shares (<5%) of the personal car fleets in BKK, HCMC, and Yangon. Euro3 was generally the most advanced technology found in other fleets in these cities. Motorcycles (MC) was the most dominant fleet in all cities, except in Yangon, where they were not allowed. Low vehicle speeds, mainly below 25 km/h, were observed for all vehicle types, indicating traffic jams. Natural gas and LPG had considerable shares in BKK and Yangon while for other cities diesel and gasoline were still the two major fuels used in transportation. Running emission factors (EF) of buses and taxis in Kathmandu were considerably higher than other cities due to its hilly topography, low speeds, high mileage, and less advanced vehicle technologies. The number of passenger vehicles per 1000 people were 400-500 in HCMC and Hanoi (mainly by MC) and in BKK (also by cars), moderate in Kathmandu (200) and the lowest in Yangon (40) because of the MC ban. Annual emissions of the passenger fleets were calculated for each city using the International Vehicle Emission (IVE) for 14 species. BC and OC emissions were estimated using their fractions of PM10 emission. Annual emission per capita of toxic air pollutants and GHGs was analyzed. For example, the emission in kg/year/person for CO, VOC, NOx and PM10 in these cities was 24-150 for CO, 0

  13. Grieving while Driving

    ERIC Educational Resources Information Center

    Rosenblatt, Paul C.

    2004-01-01

    Secondary analysis of data from 84 people in 2 interview studies shows that some bereaved people grieve actively while driving. The grief can be intense, even years after a death. Grief while driving may erupt spontaneously or be set off by a wide range of reminders. Some bereaved people seem to save their grieving for times when they drive,…

  14. A Transformerless Hybrid Active Filter Capable of Complying with Harmonic Guidelines for Medium-Voltage Motor Drives

    NASA Astrophysics Data System (ADS)

    Kondo, Ryota; Akagi, Hirofumi

    This paper presents a transformerless hybrid active filter that is integrated into medium-voltage adjustable-speed motor drives for fans, pumps, and compressors without regenerative braking. The authors have designed and constructed a three-phase experimental system rated at 400V and 15kW, which is a downscaled model from a feasible 6.6-kV 1-MW motor drive system. This system consists of the hybrid filter connecting a passive filter tuned to the 7th harmonic filter in series with an active filter that is based on a three-level diode-clamped PWM converter, as well as an adjustable-speed motor drive in which a diode rectifier is used as the front end. The hybrid filter is installed on the ac side of the diode rectifier with no line-frequency transformer. The downscaled system has been exclusively tested so as to confirm the overall compensating performance of the hybrid filter and the filtering performance of a switching-ripple filter for mitigating switching-ripple voltages produced by the active filter. Experimental results verify that the hybrid filter achieves harmonic compensation of the source current in all the operating regions from no-load to the rated-load conditions, and that the switching-ripple filter reduces the switching-ripple voltages as expected.

  15. WINDROW AND STATIC PILE COMPOSTING OF MUNICIPAL SEWAGE SLUDGES

    EPA Science Inventory

    Research was conducted on composting anaerobically digested and centrifuge dewatered sewage sludge from 1975 through 1980. Windrow and static pile composting processes were evaluated; new methods were employed using deeper windrows and aerated static piles were constructed withou...

  16. 6. CANNERY PILINGS Foundation of a portion of the cannery ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. CANNERY PILINGS Foundation of a portion of the cannery over water. Crumbling cement footings and decomposing pilings make portions of this area unsafe. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

  17. 30 CFR 77.215 - Refuse piles; construction requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... constructed in compacted layers not exceeding 2 feet in thickness and shall not have any slope exceeding 2... stability of the refuse pile. (j) All fires in refuse piles shall be extinguished, and the method used...

  18. 30 CFR 77.215 - Refuse piles; construction requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... constructed in compacted layers not exceeding 2 feet in thickness and shall not have any slope exceeding 2... stability of the refuse pile. (j) All fires in refuse piles shall be extinguished, and the method used...

  19. 30 CFR 77.215 - Refuse piles; construction requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... constructed in compacted layers not exceeding 2 feet in thickness and shall not have any slope exceeding 2... stability of the refuse pile. (j) All fires in refuse piles shall be extinguished, and the method used...

  20. RUNX2 and the PI3K/AKT axis reciprocal activation as a driving force for tumor progression.

    PubMed

    Cohen-Solal, Karine A; Boregowda, Rajeev K; Lasfar, Ahmed

    2015-01-01

    From the first reported role of the transcription factor RUNX2 in osteoblast and chondrocyte differentiation and migration to its involvement in promigratory/proinvasive behavior of breast, prostate, and thyroid cancer cells, osteosarcoma, or melanoma cells, RUNX2 currently emerges as a key player in metastasis. In this review, we address the interaction of RUNX2 with the PI3K/AKT signaling pathway, one of the critical axes controlling cancer growth and metastasis. AKT, either by directly phosphorylating/activating RUNX2 or phosphorylating/inactivating regulators of RUNX2 stability or activity, contributes to RUNX2 transcriptional activity. Reciprocally, the activation of the PI3K/AKT pathway by RUNX2 regulation of its different components has been described in non-transformed and transformed cells. This mutual activation in the context of cancer cells exhibiting constitutive AKT activation and high levels of RUNX2 might constitute a major driving force in tumor progression and aggressiveness. PMID:26204939

  1. Use of a magnetic field to modify and detect avalanche behavior on a conical bead pile

    NASA Astrophysics Data System (ADS)

    Johnson, Nathan; Lehman, Susan

    2015-03-01

    A conical bead pile subject to slow driving and an external magnetic field is used to test the effects of drop height and cohesion on avalanche statistics. Magnetically susceptible beads were dropped onto a pile from different heights and into different strengths of magnetic field. Avalanches were recorded by the change in mass as beads fall off the pile. For beads dropped from a low drop height with no cohesion, the avalanche size distribution follows a power law. As cohesion increases, we observe an increase in the probability of very large avalanches and decreases in the mid-size avalanches. The resulting bump in the avalanche distribution moves to larger avalanche size as the cohesion in the system is increased, matching the prediction by an analytic theory from a mean-field model of slip avalanches. The model also makes predictions for avalanche duration, which is not measurable with our current system. Since the steel beads are magnetized while in the applied magnetic field, their motion during an avalanche creates a change in magnetic flux. To detect this motion, we have placed a large-diameter pick-up coil around the pile. Results of the testing and calibration of this coil to measure avalanche duration are presented.

  2. Activating FGFR3 mutations cause mild hyperplasia in human skin, but are insufficient to drive benign or malignant skin tumors

    PubMed Central

    Duperret, Elizabeth K; Oh, Seung Ja; McNeal, Andrew; Prouty, Stephen M; Ridky, Todd W

    2014-01-01

    Fibroblast growth factor receptor 3 (FGFR3) activating mutations are drivers of malignancy in several human tissues, including bladder, lung, cervix, and blood. However, in skin, these mutations are associated predominantly with benign, common epidermal growths called seborrheic keratoses (SKs). How epidermis resists FGFR3 mediated transformation is unclear, but previous studies have suggested that FGFR3 activation in skin keratinocytes may serve a tumor-suppressive role by driving differentiation and antagonizing Ras signaling. To define the role of FGFR3 in human normal and neoplastic epidermis, and to directly test the hypothesis that FGFR3 antagonizes Ras, we engineered human skin grafts in vivo with mutant active FGFR3 or shRNA FGFR3 knockdown. We show that FGFR3 active mutants drive mild hyperproliferation, but are insufficient to support benign or malignant tumorigenesis, either alone, or in combination with G1–S checkpoint release. This suggests that additional cell-intrinsic or stromal cues are required for formation of benign SKs with FGFR3 mutations. Further, FGFR3 activation does not alter the growth kinetics or differentiation status of engineered human epidermal SCCs driven by Ras, and FGFR3 protein itself is dispensable for Ras-driven SCC. To extend these findings to patients, we examined a uniquely informative human tumor in which SCC developed in continuity with a SK, raising the hypothesis that one of the tumors evolved from the other. However, mutational analysis from each tumor indicates that the overlapping SK and SCC evolved independently and supports our conclusion that FGFR3 activation is insufficient to drive SCC. PMID:24626198

  3. Respiration drives network activity and modulates synaptic and circuit processing of lateral inhibition in the olfactory bulb

    PubMed Central

    Phillips, Matthew E.; Sachdev, Robert N. S.; Willhite, David C.; Shepherd, Gordon M.

    2012-01-01

    Respiration produces rhythmic activity in the entire olfactory system, driving neurons in the olfactory epithelium, bulb (OB) and cortex. The rhythmic nature of this activity is believed to be a critical component of sensory processing. OB projection neurons, mitral and tufted cells, exhibit both spiking and subthreshold membrane potential oscillations rhythmically coupled to respiration. Yet, the network and synaptic mechanisms that produce respiration-coupled activity, and the effects of respiration on lateral inhibition, a major component of sensory processing in OB circuits, are not known. Is respiration-coupled activity in mitral and tufted cells produced by sensory synaptic inputs from nasal airflow alone, cortico-bulbar feedback, or intrinsic membrane properties of the projection neurons? Does respiration facilitate or modulate the activity of inhibitory lateral circuits in the OB? Here, in vivo intracellular recordings from identified mitral and tufted cells in anesthetized rats demonstrate that nasal airflow provides excitatory synaptic inputs to both cell types and drives respiration-coupled spiking. Lateral inhibition, inhibitory post-synaptic potentials evoked by intrabulbar microstimulation, was modulated by respiration. In individual mitral and tufted cells inhibition was larger at specific respiratory phases. However, lateral inhibition was not uniformly larger during a particular respiratory phase in either cell type. Removing nasal airflow abolished respiration-coupled spiking in both cell types and nearly eliminated spiking in mitral, but not tufted cells. In the absence of nasal airflow, lateral inhibition was weaker in mitral cells and less modulated in tufted cells. Thus, respiration drives distinct network activities that functionally modulate sensory processing in the OB. PMID:22219272

  4. The LMP1 oncogene of EBV activates PERK and the unfolded protein response to drive its own synthesis

    PubMed Central

    Lee, Dong Yun

    2008-01-01

    The oncogene latent membrane protein 1 (LMP1) of Epstein-Barr virus (EBV) without a ligand drives proliferation of EBV-infected B cells. Its levels vary in cells of clonal populations by more than 100-fold, which leads to multiple distinct activities of the oncogene. At intermediate levels it drives proliferation, and at high levels it inhibits general protein synthesis by inducing phosphorylation of eukaryotic initiation factor 2α (eIF2α). We have found that LMP1 activates PERK to induce phosphorylation of eIF2α, which upregulates activating transcription factor 4 (ATF4) expression. ATF4, in turn, transactivates LMP1's own promoter. LMP1 activates not only PERK but also inositol requiring kinase 1 (IRE1) and ATF6, 3 pathways of the unfolded protein response (UPR). Increasing expression levels of LMP1 induced a dose-dependent increase in IRE1 activity, as measured by its “splicing” of XBP-1. These infected B cells secrete immunoglobins independent of the levels of LMP1, indicating that only a threshold level of XBP-1 is required for the secretion. These findings indicate that LMP1's activation of the UPR is a normal event in a continuum of LMP1's expression that leads both to stimulatory and inhibitory functions and regulates the physiology of EBV-infected B cells in multiple, unexpected modes. PMID:18042799

  5. Argonne nuclear pioneers: Chicago Pile 1

    SciTech Connect

    Agnew, Harold; Nyer, Warren

    2012-01-01

    On December 2, 1942, 49 scientists, led by Enrico Fermi, made history when Chicago Pile 1 (CP-1) went critical and produced the world's first self-sustaining, controlled nuclear chain reaction. Seventy years later, two of the last surviving CP-1 pioneers, Harold Agnew and Warren Nyer, recall that historic day.

  6. Argonne nuclear pioneers: Chicago Pile 1

    ScienceCinema

    Agnew, Harold; Nyer, Warren

    2013-04-19

    On December 2, 1942, 49 scientists, led by Enrico Fermi, made history when Chicago Pile 1 (CP-1) went critical and produced the world's first self-sustaining, controlled nuclear chain reaction. Seventy years later, two of the last surviving CP-1 pioneers, Harold Agnew and Warren Nyer, recall that historic day.

  7. 40 CFR 264.554 - Staging piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Professional Engineer for technical data, such as design drawings and specifications, and engineering studies... operation; (ii) Volumes of wastes you intend to store in the pile; (iii) Physical and chemical characteristics of the wastes to be stored in the unit; (iv) Potential for releases from the unit;...

  8. Improve large-engine foundations by good piling design, installation

    SciTech Connect

    Kauffmann, W.M.

    1982-07-01

    Specifies types of underpinning for sites holding generator sets upward of 3000 kW which may need more support than the foundation block alone can give. Four basic types of piling are in use today: concrete-filled steel pipe, steel H beams, prestressed concrete, and wood. Design of a piling foundation calls for combined skill of soil engineers, consultant, contractor, and engine builder. Attention is given to springmounted floating blocks, freestanding blocks, and structuralsteel pilings. Suggests that owners avoid sites where friction piling is required because such piling under a vibratory load is not yet an exact science.

  9. Driving simulation in the clinic: testing visual exploratory behavior in daily life activities in patients with visual field defects.

    PubMed

    Hamel, Johanna; Kraft, Antje; Ohl, Sven; De Beukelaer, Sophie; Audebert, Heinrich J; Brandt, Stephan A

    2012-01-01

    Patients suffering from homonymous hemianopia after infarction of the posterior cerebral artery (PCA) report different degrees of constraint in daily life, despite similar visual deficits. We assume this could be due to variable development of compensatory strategies such as altered visual scanning behavior. Scanning compensatory therapy (SCT) is studied as part of the visual training after infarction next to vision restoration therapy. SCT consists of learning to make larger eye movements into the blind field enlarging the visual field of search, which has been proven to be the most useful strategy(1), not only in natural search tasks but also in mastering daily life activities(2). Nevertheless, in clinical routine it is difficult to identify individual levels and training effects of compensatory behavior, since it requires measurement of eye movements in a head unrestrained condition. Studies demonstrated that unrestrained head movements alter the visual exploratory behavior compared to a head-restrained laboratory condition(3). Martin et al.(4) and Hayhoe et al.(5) showed that behavior demonstrated in a laboratory setting cannot be assigned easily to a natural condition. Hence, our goal was to develop a study set-up which uncovers different compensatory oculomotor strategies quickly in a realistic testing situation: Patients are tested in the clinical environment in a driving simulator. SILAB software (Wuerzburg Institute for Traffic Sciences GmbH (WIVW)) was used to program driving scenarios of varying complexity and recording the driver's performance. The software was combined with a head mounted infrared video pupil tracker, recording head- and eye-movements (EyeSeeCam, University of Munich Hospital, Clinical Neurosciences). The positioning of the patient in the driving simulator and the positioning, adjustment and calibration of the camera is demonstrated. Typical performances of a patient with and without compensatory strategy and a healthy control are

  10. Driving Simulation in the Clinic: Testing Visual Exploratory Behavior in Daily Life Activities in Patients with Visual Field Defects

    PubMed Central

    Hamel, Johanna; Kraft, Antje; Ohl, Sven; De Beukelaer, Sophie; Audebert, Heinrich J.; Brandt, Stephan A.

    2012-01-01

    Patients suffering from homonymous hemianopia after infarction of the posterior cerebral artery (PCA) report different degrees of constraint in daily life, despite similar visual deficits. We assume this could be due to variable development of compensatory strategies such as altered visual scanning behavior. Scanning compensatory therapy (SCT) is studied as part of the visual training after infarction next to vision restoration therapy. SCT consists of learning to make larger eye movements into the blind field enlarging the visual field of search, which has been proven to be the most useful strategy1, not only in natural search tasks but also in mastering daily life activities2. Nevertheless, in clinical routine it is difficult to identify individual levels and training effects of compensatory behavior, since it requires measurement of eye movements in a head unrestrained condition. Studies demonstrated that unrestrained head movements alter the visual exploratory behavior compared to a head-restrained laboratory condition3. Martin et al.4 and Hayhoe et al.5 showed that behavior demonstrated in a laboratory setting cannot be assigned easily to a natural condition. Hence, our goal was to develop a study set-up which uncovers different compensatory oculomotor strategies quickly in a realistic testing situation: Patients are tested in the clinical environment in a driving simulator. SILAB software (Wuerzburg Institute for Traffic Sciences GmbH (WIVW)) was used to program driving scenarios of varying complexity and recording the driver's performance. The software was combined with a head mounted infrared video pupil tracker, recording head- and eye-movements (EyeSeeCam, University of Munich Hospital, Clinical Neurosciences). The positioning of the patient in the driving simulator and the positioning, adjustment and calibration of the camera is demonstrated. Typical performances of a patient with and without compensatory strategy and a healthy control are illustrated in

  11. Isotopically enriched ammonium shows high nitrogen transformation in the pile top zone of dairy manure compost

    NASA Astrophysics Data System (ADS)

    Maeda, Koki; Toyoda, Sakae; Yano, Midori; Hattori, Shohei; Fukasawa, Makoto; Nakajima, Keiichi; Yoshida, Naohiro

    2016-03-01

    Nitrogen isotope ratios (δ15N) of NH4+ in dairy manure compost piles with and without bulking agent (10 % w/w) were compared to understand the effects of the use of bulking agent on nitrogen conversion during manure composting. The δ15N-NH4+ values in each of three pile zones (top, side and core) were also compared. At the end of the process, piles with bulking agent showed significantly higher δ15N values (17.7 ± 1.3 ‰) than piles without bulking agent (11.8 ± 0.9 ‰), reflecting the significantly higher nitrogen conversion and NH3 loss in the former. The samples from the top zone, especially in the piles with bulking agent, showed very high NH4+ concentrations with significantly high 15N (δ15N: 12.7-29.8 ‰) values, indicating that extremely high nitrogen conversion, nitrification-denitrification activity of the microbes and NH3 volatilization occurred in this zone.

  12. The Strength of Rubble Pile Asteroids

    NASA Astrophysics Data System (ADS)

    Scheeres, D. J.; Sanchez, P.

    2012-12-01

    The rubble pile hypothesis for small asteroids in the Near Earth and Main Belt populations have been driven by several factors, including the observed high porosity of those bodies whose mass have been measured, the evident limitation on spin rate of asteroids larger than ~500 meters, and direct observation of the surface morphology of these bodies. Given these observations, it has been presumed that small asteroids should evolve as if they were cohesionless collections of grains. Detailed geophysical analysis of these bodies by Holsapple (Icarus 2010) show that cohesionless bodies will evolve under the addition of angular momentum by the YORP effect into more distended and, paradoxically, more slowly rotating bodies. Additional analysis in Holsapple (Icarus 2007) has shown that cohesional strength within a rubble pile could strengthen a collection of grains to the point where they could sustain rapid rotation. In our current talk we use the above as a starting point and incorporate new observations of the asteroid morphology driven by recent analysis of asteroid Itokawa by the Hayabusa science team and research on the mechanics of grains in the space environment (Scheeres et al. 2010). Analysis of images of Itokawa determined a measured size distribution of 1/d^3 for larger grains on asteroid Itokawa (Michikami et al., Earth Planets Space, 60, 13-20, 2008). Analysis of the sample shows the presence of micron sized dust on that asteroid's surface (Tsuchiyama et al., Science 333, 1125, 2011). Combining these observations provides a global indication of grain distribution within rubble piles. Even assuming a less steep distribution of 1/d^2 for dust grains smaller than 1 mm in size, the interior of Itokawa should still be dominated by the finest dust grains, with the mean grain size equal to ~ twice the smallest grain in the distribution. One implication of this result is that fines are present on the surface of the rubble pile Itokawa and thus should be distributed

  13. Numerical analysis of kinematic soil-pile interaction

    SciTech Connect

    Castelli, Francesco; Maugeri, Michele; Mylonakis, George

    2008-07-08

    In the present study, the response of singles pile to kinematic seismic loading is investigated using the computer program SAP2000. The objectives of the study are: (1) to develop a numerical model that can realistically simulate kinematic soil-structure interaction for piles accounting for discontinuity conditions at the pile-soil interface, energy dissipation and wave propagation; (2) to use the model for evaluating kinematic interaction effects on pile response as function of input ground motion; and (3) to present a case study in which theoretical predictions are compared with results obtained from other formulations. To evaluate the effects of kinematic loading, the responses of both the free-field soil (with no piles) and the pile were compared. Time history and static pushover analyses were conducted to estimate the displacement and kinematic pile bending under seismic loadings.

  14. Numerical analysis of kinematic soil—pile interaction

    NASA Astrophysics Data System (ADS)

    Castelli, Francesco; Maugeri, Michele; Mylonakis, George

    2008-07-01

    In the present study, the response of singles pile to kinematic seismic loading is investigated using the computer program SAP2000@. The objectives of the study are: (1) to develop a numerical model that can realistically simulate kinematic soil-structure interaction for piles accounting for discontinuity conditions at the pile-soil interface, energy dissipation and wave propagation; (2) to use the model for evaluating kinematic interaction effects on pile response as function of input ground motion; and (3) to present a case study in which theoretical predictions are compared with results obtained from other formulations. To evaluate the effects of kinematic loading, the responses of both the free-field soil (with no piles) and the pile were compared. Time history and static pushover analyses were conducted to estimate the displacement and kinematic pile bending under seismic loadings.

  15. Picking up Clues from the Discard Pile

    NASA Technical Reports Server (NTRS)

    2008-01-01

    As NASA's Phoenix Mars Lander excavates trenches, it also builds piles with most of the material scooped from the holes. The piles, like this one called 'Caterpillar,' provide researchers some information about the soil.

    On Aug. 24, 2008, during the late afternoon of the 88th Martian day after landing, Phoenix's Surface Stereo Imager took separate exposures through red, green and blue filters that have been combined into this approximately true-color image.

    This conical pile of soil is about 10 centimeters (4 inches) tall. The sources of material that the robotic arm has dropped onto the Caterpillar pile have included the 'Dodo' and ''Upper Cupboard' trenches and, more recently, the deeper 'Stone Soup' trench.

    Observations of the pile provide information, such as the slope of the cone and the textures of the soil, that helps scientists understand properties of material excavated from the trenches.

    For the Stone Soup trench in particular, which is about 18 centimeters (7 inches) deep, the bottom of the trench is in shadow and more difficult to observe than other trenches that Phoenix has dug. The Phoenix team obtained spectral clues about the composition of material from the bottom of Stone Soup by photographing Caterpillar through 15 different filters of the Surface Stereo Imager when the pile was covered in freshly excavated material from the trench.

    The spectral observation did not produce any sign of water-ice, just typical soil for the site. However, the bigger clumps do show a platy texture that could be consistent with elevated concentration of salts in the soil from deep in Stone Soup. The team chose that location as the source for a soil sample to be analyzed in the lander's wet chemistry laboratory, which can identify soluble salts in the soil.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif

  16. Monte Carlo simulation of pulse pile-up effect in gamma spectrum of a PGNAA system

    NASA Astrophysics Data System (ADS)

    Mowlavi, Ali Asghar; Hadizadeh Yazdi, Mohammad Hadi

    2011-12-01

    We have applied a pile-up Monte Carlo simulation code on gamma spectrum of a prompt gamma neutron activation analysis (PGNAA) system. The code has been run in nonparalyzable mode for a specific geometry of a PGNAA system with 241Am-9Be source and NaI(Tl) detector to obtain the distortion due to “pile-up” in the pulse height of gamma spectrum. The results show that the main background in the nitrogen region of interest (ROI) is due to two pile-ups. We have also evaluated the variation of count rate and total photon sampling over the Monte Carlo spectra. At high count rates, not only the nitrogen ROI but also carbon ROI, and hydrogen peak are disturbed strongly. Comparison between the results of simulations and the experimental spectra has shown a good agreement. The code could be used for other source setups and different gamma detection systems.

  17. The association of physical activity, cognitive processes and automobile driving ability in older adults: A review of the literature.

    PubMed

    Miller, Sally M; Taylor-Piliae, Ruth E; Insel, Kathleen C

    2016-01-01

    As the number of older adults in the United States grows, the number of automobile drivers over the age of 65 will also increase. Several cognitive processes necessary for automobile driving are vulnerable to age-related decline. These include declines in executive function, working memory, attention, and speed of information processing. The benefits of physical activity on physical, psychological and particular cognitive processes are well-documented; however few studies have explored the relationship between physical activity and driving ability in older adults or examined if cognitive processes mediate (or moderate) the effect of physical activity on driving ability. The purpose of this paper is to review the existing literature regarding physical activity, cognition and automobile driving. Recommendations for further research and utility of the findings to nursing and the health care team are provided. PMID:27260109

  18. iDriving (Intelligent Driving)

    2012-09-17

    iDriving identifies the driving style factors that have a major impact on fuel economy. An optimization framework is used with the aim of optimizing a driving style with respect to these driving factors. A set of polynomial metamodels is constructed to reflect the responses produced in fuel economy by changing the driving factors. The optimization framework is used to develop a real-time feedback system, including visual instructions, to enable drivers to alter their driving stylesmore » in responses to actual driving conditions to improve fuel efficiency.« less

  19. iDriving (Intelligent Driving)

    SciTech Connect

    Malikopoulos, Andreas

    2012-09-17

    iDriving identifies the driving style factors that have a major impact on fuel economy. An optimization framework is used with the aim of optimizing a driving style with respect to these driving factors. A set of polynomial metamodels is constructed to reflect the responses produced in fuel economy by changing the driving factors. The optimization framework is used to develop a real-time feedback system, including visual instructions, to enable drivers to alter their driving styles in responses to actual driving conditions to improve fuel efficiency.

  20. Polyhedron Modeling of Rubble-Pile Asteroids

    NASA Technical Reports Server (NTRS)

    Korycansky, D. G.; Asphaug, E.

    2005-01-01

    We report on progress in modeling of asteroids as collections of rigid polyhedra ("rubble piles"). Such models are (idealized) candidates for asteroid structures: aggregates of irregular rocky subunits that are held together by self-gravity and friction. We have taken several steps toward greater realism and physical interest in construction of the models (although the gravitational fields are being treated in a simplified manner). -

  1. CENTRIFUGAL VIBRATION TEST OF RC PILE FOUNDATION

    NASA Astrophysics Data System (ADS)

    Higuchi, Shunichi; Tsutsumiuchi, Takahiro; Otsuka, Rinna; Ito, Koji; Ejiri, Joji

    It is necessary that nonlinear responses of structures are clarified by soil-structure interaction analysis for the purpose of evaluating the seismic performances of underground structure or foundation structure. In this research, centrifuge shake table tests of reinforced concrete pile foundation installed in the liquefied ground were conducted. Then, finite element analyses for the tests were conducted to confirm an applicability of the analytical method by comparing the experimental results and analytical results.

  2. From Compass to Hard Drive--Integrated Activities for Studying Magnets

    ERIC Educational Resources Information Center

    Dean, J.; Allwood, D. A.

    2014-01-01

    We describe a range of practical activities that allows students to investigate the properties and applications of magnets. The activities can be used in isolation or used together to build a rounded understanding of the subject area. The activities include simple demonstrations using common or inexpensive equipment, hands-on experiments for small…

  3. Activity-dependent synaptic GRIP1 accumulation drives synaptic scaling up in response to action potential blockade

    PubMed Central

    Gainey, Melanie A.; Tatavarty, Vedakumar; Nahmani, Marc; Lin, Heather; Turrigiano, Gina G.

    2015-01-01

    Synaptic scaling is a form of homeostatic plasticity that stabilizes neuronal firing in response to changes in synapse number and strength. Scaling up in response to action-potential blockade is accomplished through increased synaptic accumulation of GluA2-containing AMPA receptors (AMPAR), but the receptor trafficking steps that drive this process remain largely obscure. Here, we show that the AMPAR-binding protein glutamate receptor-interacting protein-1 (GRIP1) is essential for regulated synaptic AMPAR accumulation during scaling up. Synaptic abundance of GRIP1 was enhanced by activity deprivation, directly increasing synaptic GRIP1 abundance through overexpression increased the amplitude of AMPA miniature excitatory postsynaptic currents (mEPSCs), and shRNA-mediated GRIP1 knockdown prevented scaling up of AMPA mEPSCs. Furthermore, knockdown and replace experiments targeting either GRIP1 or GluA2 revealed that scaling up requires the interaction between GRIP1 and GluA2. Finally, GRIP1 synaptic accumulation during scaling up did not require GluA2 binding. Taken together, our data support a model in which activity-dependent trafficking of GRIP1 to synaptic sites drives the forward trafficking and enhanced synaptic accumulation of GluA2-containing AMPAR during synaptic scaling up. PMID:26109571

  4. Optogenetic drive of neocortical pyramidal neurons generates fMRI signals that are correlated with spiking activity

    PubMed Central

    Kahn, I.; Knoblich, U.; Desai, M.; Bernstein, J.; Graybiel, A.M.; Boyden, E.S.; Buckner, R.L.; Moore, C.I.

    2013-01-01

    Local fluctuations in the blood oxygenation level-dependent (BOLD) signal serve as the basis of functional magnetic resonance imaging (fMRI). Understanding the correlation between distinct aspects of neural activity and the BOLD response is fundamental to the interpretation of this widely used mapping signal. Analysis of this question requires the ability to precisely manipulate the activity of defined neurons. To achieve such control, we combined optogenetic drive of neocortical neurons with high-resolution (9.4 T) rodent fMRI and detailed analysis of neurophysiological data. Light-driven activation of pyramidal neurons resulted in a positive BOLD response at the stimulated site. To help differentiate the neurophysiological correlate(s) of the BOLD response, we employed light trains of the same average frequency, but with periodic and Poisson distributed pulse times. These different types of pulse trains generated dissociable patterns of single-unit, multi-unit and local field potential (LFP) activity, and of BOLD signals. The BOLD activity exhibited the strongest correlation to spiking activity with increasing rates of stimulation, and, to a first approximation, was linear with pulse delivery rate, while LFP activity showed a weaker correlation. These data provide an example of a strong correlation between spike rate and the BOLD response. PMID:23523914

  5. Characterising the interaction of individual-wheel drives with traction by linear parameter-varying model: a method for analysing the role of traction in torsional vibrations in wheel drives and active damping

    NASA Astrophysics Data System (ADS)

    Zhun Yeap, Khang; Müller, Steffen

    2016-02-01

    A model-based approach for characterising the interaction of individual-wheel drives with traction is contributed in this article. The primary aim is to investigate the influence of traction on torsional vibration behaviour in the drive train. The essence of this approach lies in reformulating the nonlinear traction behaviour into its differential form, which enables an analytical description of this interaction in its linear parameter-varying model equivalence. Analytical statements on the vibration behaviour for different driving scenarios are inferred from this model and validated with measurement samples from a high-performance electric road vehicle. Subsequent influences of traction on the performance of active damping of torsional vibrations are derived from this model.

  6. Impaired Driving

    MedlinePlus

    ... Risk Factors BAC Effects Prevention Additional Resources How big is the problem? In 2014, 9,967 people ... Driving: A Threat to Everyone (October 2011) Additional Data Drunk Driving State Data and Maps Motor Vehicle ...

  7. Drugged Driving

    MedlinePlus

    ... Infographics » Drugged Driving Drugged Driving Email Facebook Twitter Text Description of Infographic Top Right Figure : In 2009, ... crash than those who don't smoke. Bottom Text: Develop Social Strategies Offer to be a designated ...

  8. Effects of Non-Driving Cognitive Activity on Driver's Eye Movement and Their Individual Difference

    NASA Astrophysics Data System (ADS)

    Itoh, Makoto; Inagaki, Toshiyuki

    This paper investigates effects on driver's eye movement when the driver is distracted by a secondary cognitive task that demands a high mental workload. By observing drivers behavior in a fixed-base driving simulator, we analyze how the time lengths of eye fixations change when a driver is imposed to perform a cognitive secondary task. The results show that two types (Type 1: the number of short fixations increases, Type 2: the number of short fixations decreases) are found. Interestingly, our data show that both types can be seen even in one driver depending on traffic conditions. It is also shown that likelihood of occurring Type 1 or Type 2 effects depends on driver. The data suggest that it is possible to predict which effect is likely to occur for a driver if we analyze his or her eye movement under normal conditions. With these findings, this study developed and improved a driver-adaptable algorithm for detecting the state of being under high mental workload. The results suggest that the time length of an eye fixation can be useful index at least several drivers.

  9. Prediction of AMD generation potential in mining waste piles, in the Sarcheshmeh porphyry copper deposit, Iran.

    PubMed

    Modabberi, Soroush; Alizadegan, Ali; Mirnejad, Hassan; Esmaeilzadeh, Esmat

    2013-11-01

    This study investigates the possibility of acid mine drainage (AMD) generation in active and derelict mine waste piles in Sarcheshmeh Copper Mine produced in several decades, using static tests including acid-base accounting (ABA) and net acid-generating pH (NAGpH). In this study, 51 composite samples were taken from 11 waste heaps, and static ABA and NAGpH tests were carried out on samples. While some piles are acid producing at present and AMD is discharging from the piles, most of them do not show any indication on their AMD potential, and they were investigated to define their acid-producing potential. The analysis of data indicates that eight waste piles are potentially acid generating with net neutralization potentials (NNPs) of -56.18 to -199.3, net acid generating of 2.19-3.31, and NPRs from 0.18 to 0.44. Other waste piles exhibited either a very low sulfur, high carbonate content or excess carbonate over sulfur; hence, they are not capable of acid production or they can be considered as weak acid producers. Consistency between results of ABA and NAGpH tests using a variety of classification criteria validates these tests as powerful means for preliminary evaluation of AMD/ARD possibilities in any mining district. It is also concluded that some of the piles with very negative NNPs are capable to produce AMD naturally, and they can be used in heap leaching process for economic recovery of trace amounts of metals without applying any biostimulation methods. PMID:23813094

  10. Litter use by laying hens in a commercial aviary: dust bathing and piling.

    PubMed

    Campbell, D L M; Makagon, M M; Swanson, J C; Siegford, J M

    2016-01-01

    The laying hen industry, including in the United States, is responding to social concerns about hen welfare by implementing alternative housing systems such as the aviary, to provide more space and resources to large groups of hens. Data detailing the behavior of hens in commercial aviaries is needed to determine hens' use of the resources in order to understand their impact on hen welfare. The open litter area of aviaries provides additional space for hens during the day. Litter is also a substrate for dust bathing which is a strongly motivated natural behavior. Hens are often synchronous in their performance of dust bathing, which may lead to overcrowding in the litter area. Additionally, the open litter area can facilitate expression of unusual behavior such as flock piling (defined as the occurrence of densely grouped clusters of hens, resulting from no obvious cause and occurring randomly throughout the day and flock cycle) which may be a welfare concern. Therefore, we conducted observations of hen occupancy of the open litter area and the performance of dust bathing and flock piling across 3 production points (peak lay, mid lay and end of lay) for two flocks of Lohmann White laying hens housed in a commercial aviary. All areas of the open litter area were occupied to the same degree. Hens performed dust bathing throughout the day but showed peak dust bathing activity in the afternoon for Flock 1 (all P < 0.001) and in the late morning for Flock 2 (all P < 0.001). Overall, 174 incidents of piling behavior were observed between the 2 flocks, with piles varying in size, duration, and time of occurrence; however, no smothering was detected. Crowding on the open litter area sometimes occurred during peak periods of synchronous dust bathing and when hens piled. Further research is needed to understand the welfare implications of individual hen use of the open litter area and the causes and welfare implications of hen piling. PMID:26354762

  11. RAS/MAPK Activation Drives Resistance to Smo Inhibition, Metastasis, and Tumor Evolution in Shh Pathway-Dependent Tumors.

    PubMed

    Zhao, Xuesong; Ponomaryov, Tatyana; Ornell, Kimberly J; Zhou, Pengcheng; Dabral, Sukriti K; Pak, Ekaterina; Li, Wei; Atwood, Scott X; Whitson, Ramon J; Chang, Anne Lynn S; Li, Jiang; Oro, Anthony E; Chan, Jennifer A; Kelleher, Joseph F; Segal, Rosalind A

    2015-09-01

    Aberrant Shh signaling promotes tumor growth in diverse cancers. The importance of Shh signaling is particularly evident in medulloblastoma and basal cell carcinoma (BCC), where inhibitors targeting the Shh pathway component Smoothened (Smo) show great therapeutic promise. However, the emergence of drug resistance limits long-term efficacy, and the mechanisms of resistance remain poorly understood. Using new medulloblastoma models, we identify two distinct paradigms of resistance to Smo inhibition. Sufu mutations lead to maintenance of the Shh pathway in the presence of Smo inhibitors. Alternatively activation of the RAS-MAPK pathway circumvents Shh pathway dependency, drives tumor growth, and enhances metastatic behavior. Strikingly, in BCC patients treated with Smo inhibitor, squamous cell cancers with RAS/MAPK activation emerged from the antecedent BCC tumors. Together, these findings reveal a critical role of the RAS-MAPK pathway in drug resistance and tumor evolution of Shh pathway-dependent tumors. PMID:26130651

  12. RAS/MAPK activation drives resistance to Smo inhibition, metastasis and tumor evolution in Shh pathway-dependent tumors

    PubMed Central

    Zhao, Xuesong; Ponomaryov, Tatyana; Ornell, Kimberly J.; Zhou, Pengcheng; Dabral, Sukriti K.; Pak, Ekaterina; Li, Wei; Atwood, Scott X.; Whitson, Ramon J.; Chang, Anne Lynn S.; Li, Jiang; Oro, Anthony E.; Chan, Jennifer A.; Kelleher, Joseph F.; Segal, Rosalind A.

    2015-01-01

    Aberrant Shh signaling promotes tumor growth in diverse cancers. The importance of Shh signaling is particularly evident in medulloblastoma and basal cell carcinoma (BCC), where inhibitors targeting the Shh pathway component Smoothened (Smo) show great therapeutic promise. However, the emergence of drug resistance limits long-term efficacy and the mechanisms of resistance remain poorly understood. Using new medulloblastoma models, we identify two distinct paradigms of resistance to Smo inhibition. Sufu mutations lead to maintenance of the Shh pathway in the presence of Smo inhibitors. Alternatively activation of the RAS/MAPK pathway circumvents Shh pathway-dependency, drives tumor growth and enhances metastatic behavior. Strikingly, in BCC patients treated with Smo inhibitor, squamous cell cancers with RAS/MAPK activation emerged from the antecedent BCC tumors. Together these findings reveal a critical role of RAS/MAPK pathway in drug resistance and tumor evolution of Shh pathway-dependent tumors. PMID:26130651

  13. Response of shallow geothermal energy pile from laboratory model tests

    NASA Astrophysics Data System (ADS)

    Marto, A.; Amaludin, A.

    2015-09-01

    In shallow geothermal energy pile systems, the thermal loads from the pile, transferred and stored in the soil will cause thermally induced settlement. This factor must be considered in the geotechnical design process to avoid unexpected hazards. Series of laboratory model tests were carried out to study the behaviour of energy piles installed in kaolin soil, subjected to thermal loads and a combination of axial and thermal loads (henceforth known as thermo-axial loads). Six tests which included two thermal load tests (35°C and 40°C) and four thermo-axial load tests (100 N and 200 N, combined with 35°C and 40°C thermal loads) were conducted. To simulate the behaviour of geothermal energy piles during its operation, the thermo-axial tests were carried out by applying an axial load to the model pile head, and a subsequent application of thermal load. The model soil was compacted at 90% maximum dry density and had an undrained shear strength of 37 kPa, thus classified as having a firm soil consistency. The behaviour of model pile, having the ultimate load capacity of 460 N, was monitored using a linear variable displacement transducer, load cell and wire thermocouple, to measure the pile head settlement, applied axial load and model pile temperature. The acquired data from this study was used to define the thermo-axial response characteristics of the energy pile model. In this study, the limiting settlement was defined as 10% of the model pile diameter. For thermal load tests, higher thermal loads induced higher values of thermal settlement. At 40°C thermal load an irreversible settlement was observed after the heating and cooling cycle was applied to the model pile. Meanwhile, the pile response to thermo-axial loads were attributed to soil consistency and the magnitude of both the axial and thermal loads applied to the pile. The higher the thermoaxial loads, the higher the settlements occurred. A slight hazard on the model pile was detected, since the settlement

  14. Pastoral and woodcutting activities drive Cedrus atlantica Mediterranean forest structure in the Moroccan Middle Atlas.

    PubMed

    Coudel, Marc; Aubert, Pierre-Marie; Aderghal, Mohammed; Hély, Christelle

    2016-03-01

    Human activities are historical ecological drivers, and we need to better understand their effects on ecosystems. In particular, they have been very important in the shaping of the Mediterranean biodiversity hotspot. Researchers and managers nonetheless lack knowledge concerning the impacts of their combinations and their current intensity on the structure of forest ecosystems of the southern part of the Mediterranean basin. In this study, we have develped a new methodology in order to understand the impacts of combined pastoral and woodcutting activities on the forest structure of the still ill-described but ecologically and economically important Moroccan Middle Atlas cedar forests. In a 40 000 ha forest, we chose 103 sites and sampled human activities through proxies and forest structures through circumference and vertical structures. A typology of sites yielded four human activity types: dominant pastoral activities, dominant oak cutting or cedar cutting activities, and an intermediate mid-disturbance type. This typology did not depend on altitude or substrate, confirming that the ecosystem structures linked to the different types depend more on human activities than on main environmental parameters. Pastoral activities modified forests the most, converting them to parklands with reduced canopies and low dynamics but high tree maturation. Woodcutting activities induced gap dynamics, favoring Cedrus atlantica in favorable environmental conditions and Quercus ilex otherwise, while they affected vertical structure depending on the local environment and competition for light and soil resources. Moderately disturbed stands showed forest maturation with low competition for light. Unlike previous studies, we found no evidence of a general degradation of cedar forests due to local human activities. However, cedar logging has reduced standing basal area regionally and one third of the sites may have vulnerable cedar populations due to pastoral activities and to

  15. Aurora A drives early signalling and vesicle dynamics during T-cell activation

    PubMed Central

    Blas-Rus, Noelia; Bustos-Morán, Eugenio; Pérez de Castro, Ignacio; de Cárcer, Guillermo; Borroto, Aldo; Camafeita, Emilio; Jorge, Inmaculada; Vázquez, Jesús; Alarcón, Balbino; Malumbres, Marcos; Martín-Cófreces, Noa B.; Sánchez-Madrid, Francisco

    2016-01-01

    Aurora A is a serine/threonine kinase that contributes to the progression of mitosis by inducing microtubule nucleation. Here we have identified an unexpected role for Aurora A kinase in antigen-driven T-cell activation. We find that Aurora A is phosphorylated at the immunological synapse (IS) during TCR-driven cell contact. Inhibition of Aurora A with pharmacological agents or genetic deletion in human or mouse T cells severely disrupts the dynamics of microtubules and CD3ζ-bearing vesicles at the IS. The absence of Aurora A activity also impairs the activation of early signalling molecules downstream of the TCR and the expression of IL-2, CD25 and CD69. Aurora A inhibition causes delocalized clustering of Lck at the IS and decreases phosphorylation levels of tyrosine kinase Lck, thus indicating Aurora A is required for maintaining Lck active. These findings implicate Aurora A in the propagation of the TCR activation signal. PMID:27091106

  16. Aurora A drives early signalling and vesicle dynamics during T-cell activation.

    PubMed

    Blas-Rus, Noelia; Bustos-Morán, Eugenio; Pérez de Castro, Ignacio; de Cárcer, Guillermo; Borroto, Aldo; Camafeita, Emilio; Jorge, Inmaculada; Vázquez, Jesús; Alarcón, Balbino; Malumbres, Marcos; Martín-Cófreces, Noa B; Sánchez-Madrid, Francisco

    2016-01-01

    Aurora A is a serine/threonine kinase that contributes to the progression of mitosis by inducing microtubule nucleation. Here we have identified an unexpected role for Aurora A kinase in antigen-driven T-cell activation. We find that Aurora A is phosphorylated at the immunological synapse (IS) during TCR-driven cell contact. Inhibition of Aurora A with pharmacological agents or genetic deletion in human or mouse T cells severely disrupts the dynamics of microtubules and CD3ζ-bearing vesicles at the IS. The absence of Aurora A activity also impairs the activation of early signalling molecules downstream of the TCR and the expression of IL-2, CD25 and CD69. Aurora A inhibition causes delocalized clustering of Lck at the IS and decreases phosphorylation levels of tyrosine kinase Lck, thus indicating Aurora A is required for maintaining Lck active. These findings implicate Aurora A in the propagation of the TCR activation signal. PMID:27091106

  17. C1q, the recognition subcomponent of the classical pathway of complement, drives microglial activation.

    PubMed

    Färber, Katrin; Cheung, Giselle; Mitchell, Daniel; Wallis, Russell; Weihe, Eberhard; Schwaeble, Wilhelm; Kettenmann, Helmut

    2009-02-15

    Microglia, central nervous system (CNS) resident phagocytic cells, persistently police the integrity of CNS tissue and respond to any kind of damage or pathophysiological changes. These cells sense and rapidly respond to danger and inflammatory signals by changing their cell morphology; by release of cytokines, chemokines, or nitric oxide; and by changing their MHC expression profile. We have shown previously that microglial biosynthesis of the complement subcomponent C1q may serve as a reliable marker of microglial activation ranging from undetectable levels of C1q biosynthesis in resting microglia to abundant C1q expression in activated, nonramified microglia. In this study, we demonstrate that cultured microglial cells respond to extrinsic C1q with a marked intracellular Ca(2+) increase. A shift toward proinflammatory microglial activation is indicated by the release of interleukin-6, tumor necrosis factor-alpha, and nitric oxide and the oxidative burst in rat primary microglial cells, an activation and differentiation process similar to the proinflammatory response of microglia to exposure to lipopolysaccharide. Our findings indicate 1) that extrinsic plasma C1q is involved in the initiation of microglial activation in the course of CNS diseases with blood-brain barrier impairment and 2) that C1q synthesized and released by activated microglia is likely to contribute in an autocrine/paracrine way to maintain and balance microglial activation in the diseased CNS tissue. PMID:18831010

  18. Subcellular optogenetic activation of Cdc42 controls local and distal signaling to drive immune cell migration

    PubMed Central

    O’Neill, Patrick R.; Kalyanaraman, Vani; Gautam, N.

    2016-01-01

    Migratory immune cells use intracellular signaling networks to generate and orient spatially polarized responses to extracellular cues. The monomeric G protein Cdc42 is believed to play an important role in controlling the polarized responses, but it has been difficult to determine directly the consequences of localized Cdc42 activation within an immune cell. Here we used subcellular optogenetics to determine how Cdc42 activation at one side of a cell affects both cell behavior and dynamic molecular responses throughout the cell. We found that localized Cdc42 activation is sufficient to generate polarized signaling and directional cell migration. The optically activated region becomes the leading edge of the cell, with Cdc42 activating Rac and generating membrane protrusions driven by the actin cytoskeleton. Cdc42 also exerts long-range effects that cause myosin accumulation at the opposite side of the cell and actomyosin-mediated retraction of the cell rear. This process requires the RhoA-activated kinase ROCK, suggesting that Cdc42 activation at one side of a cell triggers increased RhoA signaling at the opposite side. Our results demonstrate how dynamic, subcellular perturbation of an individual signaling protein can help to determine its role in controlling polarized cellular responses. PMID:26941336

  19. Subcellular optogenetic activation of Cdc42 controls local and distal signaling to drive immune cell migration.

    PubMed

    O'Neill, Patrick R; Kalyanaraman, Vani; Gautam, N

    2016-05-01

    Migratory immune cells use intracellular signaling networks to generate and orient spatially polarized responses to extracellular cues. The monomeric G protein Cdc42 is believed to play an important role in controlling the polarized responses, but it has been difficult to determine directly the consequences of localized Cdc42 activation within an immune cell. Here we used subcellular optogenetics to determine how Cdc42 activation at one side of a cell affects both cell behavior and dynamic molecular responses throughout the cell. We found that localized Cdc42 activation is sufficient to generate polarized signaling and directional cell migration. The optically activated region becomes the leading edge of the cell, with Cdc42 activating Rac and generating membrane protrusions driven by the actin cytoskeleton. Cdc42 also exerts long-range effects that cause myosin accumulation at the opposite side of the cell and actomyosin-mediated retraction of the cell rear. This process requires the RhoA-activated kinase ROCK, suggesting that Cdc42 activation at one side of a cell triggers increased RhoA signaling at the opposite side. Our results demonstrate how dynamic, subcellular perturbation of an individual signaling protein can help to determine its role in controlling polarized cellular responses. PMID:26941336

  20. The interactions between temperature and activity levels in driving metabolic rate: theory, with empirical validation from contrasting ectotherms.

    PubMed

    Halsey, L G; Matthews, P G D; Rezende, E L; Chauvaud, L; Robson, A A

    2015-04-01

    The rate of change in resting metabolic rate (RMR) as a result of a temperature increase of 10 °C is termed the temperature coefficient (Q10), which is often used to predict how an organism's total MR will change with temperature. However, this method neglects a potentially key component of MR; changes in activity level (and thus activity MR; AMR) with temperature may significantly alter the relationship between MR and temperature. The present study seeks to describe how thermal effects on total MR estimated from RMR-temperature measurements can be misleading when the contribution of activity to total MR is neglected. A simple conceptual framework illustrates that since the relationship between activity levels and temperature can be different to the relationship between RMR and temperature, a consistent relationship between RMR and total MR cannot be assumed. Thus the thermal effect on total MR can be considerably different to the thermal effect on RMR. Simultaneously measured MR and activity from three ectotherm species with differing behavioural and physiological ecologies were used to empirically examine how changes in temperature drive changes in RMR, activity level, AMR and the Q10 of MR. These species exhibited varied activity- and MR-temperature relationships, underlining the difficulty in predicting thermal influences on activity levels and total MR. These data support a model showing that thermal effects on total MR will deviate from predictions based solely on RMR; this deviation will depend upon the difference in Q10 between AMR and RMR, and the relative contribution of AMR to total MR. To develop mechanistic, predictive models for species' metabolic responses to temperature changes, empirical information about the relationships between activity levels, MR and temperature, such as reported here, is required. This will supersede predictions based on RMR alone. PMID:25575673

  1. Transcriptional co-activator PGC-1 alpha drives the formation of slow-twitch muscle fibres.

    PubMed

    Lin, Jiandie; Wu, Hai; Tarr, Paul T; Zhang, Chen-Yu; Wu, Zhidan; Boss, Olivier; Michael, Laura F; Puigserver, Pere; Isotani, Eiji; Olson, Eric N; Lowell, Bradford B; Bassel-Duby, Rhonda; Spiegelman, Bruce M

    2002-08-15

    The biochemical basis for the regulation of fibre-type determination in skeletal muscle is not well understood. In addition to the expression of particular myofibrillar proteins, type I (slow-twitch) fibres are much higher in mitochondrial content and are more dependent on oxidative metabolism than type II (fast-twitch) fibres. We have previously identified a transcriptional co-activator, peroxisome-proliferator-activated receptor-gamma co-activator-1 (PGC-1 alpha), which is expressed in several tissues including brown fat and skeletal muscle, and that activates mitochondrial biogenesis and oxidative metabolism. We show here that PGC-1 alpha is expressed preferentially in muscle enriched in type I fibres. When PGC-1 alpha is expressed at physiological levels in transgenic mice driven by a muscle creatine kinase (MCK) promoter, a fibre type conversion is observed: muscles normally rich in type II fibres are redder and activate genes of mitochondrial oxidative metabolism. Notably, putative type II muscles from PGC-1 alpha transgenic mice also express proteins characteristic of type I fibres, such as troponin I (slow) and myoglobin, and show a much greater resistance to electrically stimulated fatigue. Using fibre-type-specific promoters, we show in cultured muscle cells that PGC-1 alpha activates transcription in cooperation with Mef2 proteins and serves as a target for calcineurin signalling, which has been implicated in slow fibre gene expression. These data indicate that PGC-1 alpha is a principal factor regulating muscle fibre type determination. PMID:12181572

  2. IGF-1 drives chromogranin A secretion via activation of Arf1 in human neuroendocrine tumour cells

    PubMed Central

    Münzberg, Christin; Höhn, Katharina; Krndija, Denis; Maaß, Ulrike; Bartsch, Detlef K; Slater, Emily P; Oswald, Franz; Walther, Paul; Seufferlein, Thomas; von Wichert, Götz

    2015-01-01

    Hypersecretion is the major symptom of functional neuroendocrine tumours. The mechanisms that contribute to this excessive secretion of hormones are still elusive. A key event in secretion is the exit of secretory products from the Golgi apparatus. ADP-ribosylation factor (Arf) GTPases are known to control vesicle budding and trafficking, and have a leading function in the regulation of formation of secretory granula at the Golgi. Here, we show that Arf1 is the predominant Arf protein family member expressed in the neuroendocrine pancreatic tumour cell lines BON and QGP-1. In BON cells Arf1 colocalizes with Golgi markers as well as chromogranin A, and shows significant basal activity. The inhibition of Arf1 activity or expression significantly impaired secretion of chromogranin A. Furthermore, we show that the insulin-like growth factor 1 (IGF-1), a major regulator of growth and secretion in BON cells, induces Arf1 activity. We found that activation of Arf1 upon IGF-1 receptor stimulation is mediated by MEK/ERK signalling pathway in BON and QGP-1 cells. Moreover, the activity of Arf1 in BON cells is mediated by autocrinely secreted IGF-1, and concomitantly, autocrine IGF1 secretion is maintained by Arf1 activity. In summary, our data indicate an important regulatory role for Arf1 at the Golgi in hypersecretion in neuroendocrine cancer cells. PMID:25754106

  3. Conformational Tinkering Drives Evolution of a Promiscuous Activity through Indirect Mutational Effects.

    PubMed

    Yang, Gloria; Hong, Nansook; Baier, Florian; Jackson, Colin J; Tokuriki, Nobuhiko

    2016-08-16

    How remote mutations can lead to changes in enzyme function at a molecular level is a central question in evolutionary biochemistry and biophysics. Here, we combine laboratory evolution with biochemical, structural, genetic, and computational analysis to dissect the molecular basis for the functional optimization of phosphotriesterase activity in a bacterial lactonase (AiiA) from the metallo-β-lactamase (MBL) superfamily. We show that a 1000-fold increase in phosphotriesterase activity is caused by a more favorable catalytic binding position of the paraoxon substrate in the evolved enzyme that resulted from conformational tinkering of the active site through peripheral mutations. A nonmutated active site residue, Phe68, was displaced by ∼3 Å through the indirect effects of two second-shell trajectory mutations, allowing molecular interactions between the residue and paraoxon. Comparative mutational scanning, i.e., examining the effects of alanine mutagenesis on different genetic backgrounds, revealed significant changes in the functional roles of Phe68 and other nonmutated active site residues caused by the indirect effects of trajectory mutations. Our work provides a quantitative measurement of the impact of second-shell mutations on the catalytic contributions of nonmutated residues and unveils the underlying intramolecular network of strong epistatic mutational relationships between active site residues and more remote residues. Defining these long-range conformational and functional epistatic relationships has allowed us to better understand the subtle, but cumulatively significant, role of second- and third-shell mutations in evolution. PMID:27444875

  4. The DEG/ENaC cation channel protein UNC-8 drives activity-dependent synapse removal in remodeling GABAergic neurons.

    PubMed

    Miller-Fleming, Tyne W; Petersen, Sarah C; Manning, Laura; Matthewman, Cristina; Gornet, Megan; Beers, Allison; Hori, Sayaka; Mitani, Shohei; Bianchi, Laura; Richmond, Janet; Miller, David M

    2016-01-01

    Genetic programming and neural activity drive synaptic remodeling in developing neural circuits, but the molecular components that link these pathways are poorly understood. Here we show that the C. elegans Degenerin/Epithelial Sodium Channel (DEG/ENaC) protein, UNC-8, is transcriptionally controlled to function as a trigger in an activity-dependent mechanism that removes synapses in remodeling GABAergic neurons. UNC-8 cation channel activity promotes disassembly of presynaptic domains in DD type GABA neurons, but not in VD class GABA neurons where unc-8 expression is blocked by the COUP/TF transcription factor, UNC-55. We propose that the depolarizing effect of UNC-8-dependent sodium import elevates intracellular calcium in a positive feedback loop involving the voltage-gated calcium channel UNC-2 and the calcium-activated phosphatase TAX-6/calcineurin to initiate a caspase-dependent mechanism that disassembles the presynaptic apparatus. Thus, UNC-8 serves as a link between genetic and activity-dependent pathways that function together to promote the elimination of GABA synapses in remodeling neurons. PMID:27403890

  5. The DEG/ENaC cation channel protein UNC-8 drives activity-dependent synapse removal in remodeling GABAergic neurons

    PubMed Central

    Miller-Fleming, Tyne W; Petersen, Sarah C; Manning, Laura; Matthewman, Cristina; Gornet, Megan; Beers, Allison; Hori, Sayaka; Mitani, Shohei; Bianchi, Laura; Richmond, Janet; Miller, David M

    2016-01-01

    Genetic programming and neural activity drive synaptic remodeling in developing neural circuits, but the molecular components that link these pathways are poorly understood. Here we show that the C. elegans Degenerin/Epithelial Sodium Channel (DEG/ENaC) protein, UNC-8, is transcriptionally controlled to function as a trigger in an activity-dependent mechanism that removes synapses in remodeling GABAergic neurons. UNC-8 cation channel activity promotes disassembly of presynaptic domains in DD type GABA neurons, but not in VD class GABA neurons where unc-8 expression is blocked by the COUP/TF transcription factor, UNC-55. We propose that the depolarizing effect of UNC-8-dependent sodium import elevates intracellular calcium in a positive feedback loop involving the voltage-gated calcium channel UNC-2 and the calcium-activated phosphatase TAX-6/calcineurin to initiate a caspase-dependent mechanism that disassembles the presynaptic apparatus. Thus, UNC-8 serves as a link between genetic and activity-dependent pathways that function together to promote the elimination of GABA synapses in remodeling neurons. DOI: http://dx.doi.org/10.7554/eLife.14599.001 PMID:27403890

  6. Reducing Local Scouring at Bridge Piles Using Collars and Geobags

    PubMed Central

    Akib, Shatirah; Liana Mamat, Noor; Basser, Hossein; Jahangirzadeh, Afshin

    2014-01-01

    The present study examines the use of collars and geobags for reducing local scour around bridge piles. The efficiency of collars and geobags was studied experimentally. The data from the experiments were compared with data from earlier studies on the use of single piles with a collar and with a geobag. The results showed that using a combination of a steel collar and a geobag yields the most significant scour reduction for the front and rear piles, respectively. Moreover, the independent steel collar showed better efficiency than the independent geobag below the sediment level around the bridge piles. PMID:25247201

  7. Damage Identification of Piles Based on Vibration Characteristics

    PubMed Central

    Zhang, Xiaozhong; Yao, Wenjuan; Chen, Bo; Liu, Dewen

    2014-01-01

    A method of damage identification of piles was established by using vibration characteristics. The approach focused on the application of the element strain energy and sensitive modals. A damage identification equation of piles was deduced using the structural vibration equation. The equation contained three major factors: change rate of element modal strain energy, damage factor of pile, and sensitivity factor of modal damage. The sensitive modals of damage identification were selected by using sensitivity factor of modal damage firstly. Subsequently, the indexes for early-warning of pile damage were established by applying the change rate of strain energy. Then the technology of computational analysis of wavelet transform was used to damage identification for pile. The identification of small damage of pile was completely achieved, including the location of damage and the extent of damage. In the process of identifying the extent of damage of pile, the equation of damage identification was used in many times. Finally, a stadium project was used as an example to demonstrate the effectiveness of the proposed method of damage identification for piles. The correctness and practicability of the proposed method were verified by comparing the results of damage identification with that of low strain test. The research provided a new way for damage identification of piles. PMID:25506062

  8. Norepinephrine Drives Persistent Activity in Prefrontal Cortex via Synergistic α1 and α2 Adrenoceptors

    PubMed Central

    Jego, Sonia; Adamantidis, Antoine; Séguéla, Philippe

    2013-01-01

    Optimal norepinephrine levels in the prefrontal cortex (PFC) increase delay-related firing and enhance working memory, whereas stress-related or pathologically high levels of norepinephrine are believed to inhibit working memory via α1 adrenoceptors. However, it has been shown that activation of Gq-coupled and phospholipase C-linked receptors can induce persistent firing, a cellular correlate of working memory, in cortical pyramidal neurons. Therefore, despite its importance in stress and cognition, the exact role of norepinephrine in modulating PFC activity remains elusive. Using electrophysiology and optogenetics, we report here that norepinephrine induces persistent firing in pyramidal neurons of the PFC independent of recurrent fast synaptic excitation. This persistent excitatory effect involves presynaptic α1 adrenoceptors facilitating glutamate release and subsequent activation of postsynaptic mGluR5 receptors, and is enhanced by postsynaptic α2 adrenoceptors inhibiting HCN channel activity. Activation of α2 adrenoceptors or inhibition of HCN channels also enhances cholinergic persistent responses in pyramidal neurons, providing a mechanism of crosstalk between noradrenergic and cholinergic inputs. The present study describes a novel cellular basis for the noradrenergic control of cortical information processing and supports a synergistic combination of intrinsic and network mechanisms for the expression of mnemonic properties in pyramidal neurons. PMID:23785477

  9. Hepatocyte mitochondrial DNA drives nonalcoholic steatohepatitis by activation of TLR9

    PubMed Central

    Garcia-Martinez, Irma; Santoro, Nicola; Chen, Yonglin; Hoque, Rafaz; Ouyang, Xinshou; Caprio, Sonia; Shlomchik, Mark J.; Coffman, Robert Lee; Candia, Albert; Mehal, Wajahat Zafar

    2016-01-01

    Nonalcoholic steatohepatitis (NASH) is the most common liver disease in industrialized countries. NASH is a progressive disease that can lead to cirrhosis, cancer, and death, and there are currently no approved therapies. The development of NASH in animal models requires intact TLR9, but how the TLR9 pathway is activated in NASH is not clear. Our objectives in this study were to identify NASH-associated ligands for TLR9, establish the cellular requirement for TLR9, and evaluate the role of obesity-induced changes in TLR9 pathway activation. We demonstrated that plasma from mice and patients with NASH contains high levels of mitochondrial DNA (mtDNA) and intact mitochondria and has the ability to activate TLR9. Most of the plasma mtDNA was contained in microparticles (MPs) of hepatocyte origin, and removal of these MPs from plasma resulted in a substantial decrease in TLR9 activation capacity. In mice, NASH development in response to a high-fat diet required TLR9 on lysozyme-expressing cells, and a clinically applicable TLR9 antagonist blocked the development of NASH when given prophylactically and therapeutically. These data demonstrate that activation of the TLR9 pathway provides a link between the key metabolic and inflammatory phenotypes in NASH. PMID:26808498

  10. A spinal opsin controls early neural activity and drives a behavioral light response

    PubMed Central

    Friedmann, Drew; Hoagland, Adam; Berlin, Shai; Isacoff, Ehud Y.

    2014-01-01

    Non-visual detection of light by the vertebrate hypothalamus, pineal, and retina is known to govern seasonal and circadian behaviors [1]. However, the expression of opsins in multiple other brain structures [2–4] suggests a more expansive repertoire for light-regulation of physiology, behavior, and development. Translucent zebrafish embryos express extra-retinal opsins early on [5, 6], at a time when spontaneous activity in the developing central nervous system plays a role in neuronal maturation and circuit formation [7]. Though the presence of extra-retinal opsins is well documented, the function of direct photoreception by the central nervous system remains largely unknown. Here we show that early activity in the zebrafish spinal central pattern generator (CPG) and the earliest locomotory behavior are dramatically inhibited by physiological levels of environmental light. We find that the photo-sensitivity of this circuit is conferred by vertebrate ancient long opsin (VALopA), which we show to be a Gαi-coupled receptor that is expressed in the neurons of the spinal network. Sustained photo-activation of VALopA not only suppresses spontaneous activity but also alters the maturation of time-locked correlated network patterns. These results uncover a novel role for non-visual opsins and a mechanism for environmental regulation of spontaneous motor behavior and neural activity in a circuit previously thought to be governed only by intrinsic developmental programs. PMID:25484291

  11. Daytime spikes in dopaminergic activity drive rapid mood-cycling in mice.

    PubMed

    Sidor, M M; Spencer, S M; Dzirasa, K; Parekh, P K; Tye, K M; Warden, M R; Arey, R N; Enwright, J F; Jacobsen, J P R; Kumar, S; Remillard, E M; Caron, M G; Deisseroth, K; McClung, C A

    2015-11-01

    Disruptions in circadian rhythms and dopaminergic activity are involved in the pathophysiology of bipolar disorder, though their interaction remains unclear. Moreover, a lack of animal models that display spontaneous cycling between mood states has hindered our mechanistic understanding of mood switching. Here, we find that mice with a mutation in the circadian Clock gene (ClockΔ19) exhibit rapid mood-cycling, with a profound manic-like phenotype emerging during the day following a period of euthymia at night. Mood-cycling coincides with abnormal daytime spikes in ventral tegmental area (VTA) dopaminergic activity, tyrosine hydroxylase (TH) levels and dopamine synthesis. To determine the significance of daytime increases in VTA dopamine activity to manic behaviors, we developed a novel optogenetic stimulation paradigm that produces a sustained increase in dopamine neuronal activity and find that this induces a manic-like behavioral state. Time-dependent dampening of TH activity during the day reverses manic-related behaviors in ClockΔ19 mice. Finally, we show that CLOCK acts as a negative regulator of TH transcription, revealing a novel molecular mechanism underlying cyclic changes in mood-related behavior. Taken together, these studies have identified a mechanistic connection between circadian gene disruption and the precipitation of manic episodes in bipolar disorder. PMID:25560763

  12. Persistent activation of microglia and NADPH drive hippocampal dysfunction in experimental multiple sclerosis

    PubMed Central

    Di Filippo, Massimiliano; de Iure, Antonio; Giampà, Carmela; Chiasserini, Davide; Tozzi, Alessandro; Orvietani, Pier Luigi; Ghiglieri, Veronica; Tantucci, Michela; Durante, Valentina; Quiroga-Varela, Ana; Mancini, Andrea; Costa, Cinzia; Sarchielli, Paola; Fusco, Francesca Romana; Calabresi, Paolo

    2016-01-01

    Cognitive impairment is common in multiple sclerosis (MS). Unfortunately, the synaptic and molecular mechanisms underlying MS-associated cognitive dysfunction are largely unknown. We explored the presence and the underlying mechanism of cognitive and synaptic hippocampal dysfunction during the remission phase of experimental MS. Experiments were performed in a chronic-relapsing experimental autoimmune encephalomyelitis (EAE) model of MS, after the resolution of motor deficits. Immunohistochemistry and patch-clamp recordings were performed in the CA1 hippocampal area. The hole-board was utilized as cognitive/behavioural test. In the remission phase of experimental MS, hippocampal microglial cells showed signs of activation, CA1 hippocampal synapses presented an impaired long-term potentiation (LTP) and an alteration of spatial tests became evident. The activation of hippocampal microglia mediated synaptic and cognitive/behavioural alterations during EAE. Specifically, LTP blockade was found to be caused by the reactive oxygen species (ROS)-producing enzyme nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. We suggest that in the remission phase of experimental MS microglia remains activated, causing synaptic dysfunctions mediated by NADPH oxidase. Inhibition of microglial activation and NADPH oxidase may represent a promising strategy to prevent neuroplasticity impairment associated with active neuro-inflammation, with the aim to improve cognition and counteract MS disease progression. PMID:26887636

  13. Daytime spikes in dopaminergic activity drive rapid mood-cycling in mice

    PubMed Central

    Sidor, Michelle M.; Spencer, Sade M.; Dzirasa, Kafui; Parekh, Puja K.; Tye, Kay M.; Warden, Melissa R.; Arey, Rachel N.; Enwright, John F; Jacobsen, Jacob PR; Kumar, Sunil; Remillard, Erin M; Caron, Marc G.; Deisseroth, Karl; McClung, Colleen A

    2014-01-01

    Disruptions in circadian rhythms and dopaminergic activity are involved in the pathophysiology of bipolar disorder, though their interaction remains unclear. Moreover, a lack of animal models that display spontaneous cycling between mood states has hindered our mechanistic understanding of mood switching. Here we find that mice with a mutation in the circadian Clock gene (ClockΔ19) exhibit rapid mood-cycling, with a profound manic-like phenotype emerging during the day following a period of euthymia at night. Mood cycling coincides with abnormal daytime spikes in ventral tegmental area (VTA) dopaminergic activity, tyrosine hydroxylase (TH) levels, and dopamine synthesis. To determine the significance of daytime increases in VTA dopamine activity to manic behaviors, we developed a novel optogenetic stimulation paradigm that produces a sustained increase in dopamine neuronal activity and find that this induces a manic-like behavioral state. Time-dependent dampening of TH activity during the day reverses manic-related behaviours in ClockΔ19 mice. Finally, we show that CLOCK acts as a negative regulator of TH transcription, revealing a novel molecular mechanism underlying cyclic changes in mood-related behaviour. Taken together, these studies have identified a mechanistic connection between circadian gene disruption and the precipitation of manic episodes in bipolar disorder. PMID:25560763

  14. Minifilament Eruptions that Drive Coronal Jets in a Solar Active Region

    NASA Astrophysics Data System (ADS)

    Sterling, Alphonse C.; Moore, Ronald L.; Falconer, David; Panesar, Navdeep; Akiyama, Sachiko; Yashiro, Seiji; Gopalswamy, Nat

    2016-05-01

    Solar coronal jets are common in both coronal holes and in active regions. Recently, Sterling et al. (2015), using data from Hinode/XRT and SDO/AIA, found that coronal jets originating in polar coronal holes result from the eruption of small-scale filaments (minifilaments). The jet bright point (JBP) seen in X-rays and hotter EUV channels off to one side of the base of the jet's spire develops at the location where the minifilament erupts, consistent with the JBPs being miniature versions of typical solar flares that occur in the wake of large-scale filament eruptions. Here we consider whether active region coronal jets also result from the same minifilament-eruption mechanism, or whether they instead result from a different mechanism, such as the hitherto popular ``emerging flux'' model for jets. We present observations of an on-disk active region that produced numerous jets on 2012 June 30, using data from SDO/AIA and HMI, and from GOES/SXI. We find that several of these active region jets also originate with eruptions of miniature filaments (size scale ~20'') emanating from small-scale magnetic neutral lines of the region. This demonstrates that active region coronal jets are indeed frequently driven by minifilament eruptions. Other jets from the active region were also consistent with their drivers being minifilament eruptions, but we could not confirm this because the onsets of those jets were hidden from our view. This work was supported by funding from NASA/LWS, NASA/HGI, and Hinode.

  15. Passive Joint Forces Are Tuned to Limb Use in Insects and Drive Movements without Motor Activity

    PubMed Central

    Ache, Jan M.; Matheson, Thomas

    2013-01-01

    Summary Background Limb movements are generally driven by active muscular contractions working with and against passive forces arising in muscles and other structures. In relatively heavy limbs, the effects of gravity and inertia predominate, whereas in lighter limbs, passive forces intrinsic to the limb are of greater consequence. The roles of passive forces generated by muscles and tendons are well understood, but there has been little recognition that forces originating within joints themselves may also be important, and less still that these joint forces may be adapted through evolution to complement active muscle forces acting at the same joint. Results We examined the roles of passive joint forces in insect legs with different arrangements of antagonist muscles. We first show that passive forces modify actively generated movements of a joint across its working range, and that they can be sufficiently strong to generate completely passive movements that are faster than active movements observed in natural behaviors. We further demonstrate that some of these forces originate within the joint itself. In legs of different species adapted to different uses (walking, jumping), these passive joint forces complement the balance of strength of the antagonist muscles acting on the joint. We show that passive joint forces are stronger where they assist the weaker of two antagonist muscles. Conclusions In limbs where the dictates of a key behavior produce asymmetry in muscle forces, passive joint forces can be coadapted to provide the balance needed for the effective generation of other behaviors. PMID:23871240

  16. Oxidized LDL levels are increased in HIV infection and may drive monocyte activation

    PubMed Central

    Zidar, David A.; Juchnowski, Steven; Ferrari, Brian; Clagett, Brian; Pilch-Cooper, Heather A.; Rose, Shawn; Rodriguez, Benigno; McComsey, Grace A.; Sieg, Scott F.; Mehta, Nehal N.; Lederman, Michael M.; Funderburg, Nicholas T.

    2015-01-01

    Background Human immunodeficiency virus (HIV) infection is associated with increased cardiovascular risk, and this risk correlates with markers of monocyte activation. We have shown that HIV is associated with a prothrombotic monocyte phenotype, which can be partially mitigated by statin therapy. We therefore explored the relationship between oxidized LDL particles and monocyte activation. Methods We performed phenotypic analysis of monocytes using flow cytometry on fresh whole blood in 54 patients with HIV and 24 controls without HIV. Plasma levels of oxLDL, soluble CD14, IL-6, soluble CD163 were measured by ELISA. In vitro experiments were performed using flow cytometry. Results Plasma levels of oxLDL were significantly increased in HIV-infection compared to controls (60.1 units vs 32.1 units, p<0.001). Monocyte expression of the oxLDL receptors, CD36 and Toll-like receptor 4, were also increased in HIV. OxLDL levels correlated with markers of monocyte activation, including soluble CD14, TF expression on inflammatory monocytes, and CD36. In vitro, stimulation with oxLDL, but not to LDL, resulted in expansion of inflammatory monocytes and increased monocyte expression of TF, recapitulating the monocyte profile we find in HIV disease. Conclusions OxLDL may contribute to monocyte activation and further study in the context of HIV disease is warranted. PMID:25647528

  17. What drives centuries-long polygenetic scoria cone activity at Barren Island volcano?

    NASA Astrophysics Data System (ADS)

    Sheth, Hetu

    2014-12-01

    Barren Island in the Andaman Sea is an active mafic stratovolcano, which had explosive and effusive eruptions, followed by caldera formation, in prehistoric time (poorly dated). A scoria cone within the caldera, marking volcanic resurgence, was active periodically from 1787 to 1832 (the historic eruptions). Since 1991, the same scoria cone has produced six eruptions, commonly including lava flows. Links between Barren Island's eruptions and giant earthquakes (such as the 26 December 2004 Great Sumatra megathrust earthquake) have been suggested, though there is no general correlation between them. The ≥ 227-year-long activity of the scoria cone, named here Shanku ("cone"), is normally driven by purely magmatic processes. I present a "source to surface" model for Barren Island and Shanku, including the source region, deeper and shallow magma chambers, volcanotectonics, dyking from magma chambers, and eruptions and eruptive style as controlled by crustal stresses, composition and volatile content. Calculations show that dykes ~ 0.5 m thick and a few hundred meters long, originating from shallow-level magma chambers (~ 5 km deep), are suitable feeders of the Shanku eruptions. Shanku, a polygenetic scoria cone (at least 13 eruptions since 1787), has three excellent analogues, namely Anak Krakatau (40 eruptions since 1927), Cerro Negro (23 eruptions since 1850), and Yasur (persistent activity for the past hundreds of years). This is an important category of volcanoes, gradational between small "monogenetic" scoria cones and larger "polygenetic" volcanoes.

  18. Constitutive Lck Activity Drives Sensitivity Differences between CD8+ Memory T Cell Subsets.

    PubMed

    Moogk, Duane; Zhong, Shi; Yu, Zhiya; Liadi, Ivan; Rittase, William; Fang, Victoria; Dougherty, Janna; Perez-Garcia, Arianne; Osman, Iman; Zhu, Cheng; Varadarajan, Navin; Restifo, Nicholas P; Frey, Alan B; Krogsgaard, Michelle

    2016-07-15

    CD8(+) T cells develop increased sensitivity following Ag experience, and differences in sensitivity exist between T cell memory subsets. How differential TCR signaling between memory subsets contributes to sensitivity differences is unclear. We show in mouse effector memory T cells (TEM) that >50% of lymphocyte-specific protein tyrosine kinase (Lck) exists in a constitutively active conformation, compared with <20% in central memory T cells (TCM). Immediately proximal to Lck signaling, we observed enhanced Zap-70 phosphorylation in TEM following TCR ligation compared with TCM Furthermore, we observed superior cytotoxic effector function in TEM compared with TCM, and we provide evidence that this results from a lower probability of TCM reaching threshold signaling owing to the decreased magnitude of TCR-proximal signaling. We provide evidence that the differences in Lck constitutive activity between CD8(+) TCM and TEM are due to differential regulation by SH2 domain-containing phosphatase-1 (Shp-1) and C-terminal Src kinase, and we use modeling of early TCR signaling to reveal the significance of these differences. We show that inhibition of Shp-1 results in increased constitutive Lck activity in TCM to levels similar to TEM, as well as increased cytotoxic effector function in TCM Collectively, this work demonstrates a role for constitutive Lck activity in controlling Ag sensitivity, and it suggests that differential activities of TCR-proximal signaling components may contribute to establishing the divergent effector properties of TCM and TEM. This work also identifies Shp-1 as a potential target to improve the cytotoxic effector functions of TCM for adoptive cell therapy applications. PMID:27271569

  19. B cells drive lymphocyte activation and expansion in mice with the CD45 wedge mutation and Fas deficiency

    PubMed Central

    Gupta, Vikas A.; Hermiston, Michelle L.; Cassafer, Gail; Daikh, David I.; Weiss, Arthur

    2008-01-01

    CD45 and Fas regulate tyrosine phosphorylation and apoptotic signaling pathways, respectively. Mutation of an inhibitory wedge motif in CD45 (E613R) results in hyperresponsive thymocytes and B cells on the C57BL/6 background, but no overt autoimmunity, whereas Fas deletion results in a mild autoimmune disease on the same genetic background. In this study, we show that these two mutations cooperate in mice, causing early lethality, autoantibody production, and substantial lymphoproliferation. In double-mutant mice, this phenotype was dependent on both T and B cells. T cell activation required signaling in response to endogenous or commensal antigens, demonstrated by the introduction of a transgenic T cell receptor. Genetic deletion of B cells also prevented T cell activation. Similarly, T cells were necessary for B cell autoantibody production. However, B cells appeared to be intrinsically activated even in the absence of T cells, suggesting that they may drive the phenotype of these mice. These results reveal a requirement for careful control of B cell signaling and cell death in preventing inappropriate lymphocyte activation and autoimmunity. PMID:19001138

  20. Magnetostrictive roller drive motor

    NASA Astrophysics Data System (ADS)

    Vranish, John M.

    1992-01-01

    A magnetostrictive drive motor is disclosed which has a rotary drive shaft in the form of a drum which is encircled by a plurality of substantially equally spaced roller members in the form of two sets of cones which are in contact with the respective cam surfaces on the inside surface of an outer drive ring. The drive ring is attached to sets of opposing pairs of magnetostrictive rods. Each rod in a pair is mutually positioned end to end within respective energizing coils. When one of the coils in an opposing pair is energized, the energized rod expands while the other rod is caused to contract, causing the drive ring to rock, i.e., rotate slightly in either the clockwise or counterclockwise direction, depending upon which rod in a pair is energized. As the drive ring is activated in repetitive cycles in either direction, one set of drive cones attempts to roll up their respective cam surface but are pinned between the drive shaft drum and the drive ring. As the frictional force preventing sliding builds up, the cones become locked, setting up reaction forces including a tangential component which is imparted to the drive shaft drum to provide a source of motor torque. Simultaneously the other set of cones are disengaged from the drive shaft drum. Upon deactivation of the magnetostrictive rod coils, the force on the drive cones is released, causing the system to return to an initial rest position. By repetitively cycling the energization of the magnetostrictive rods, the drive shaft drum indexes in microradian rotational steps.

  1. A theoretical analysis of the bearing performance of vertically loaded large-diameter pipe pile groups

    NASA Astrophysics Data System (ADS)

    Ding, Xuanming; Zhang, Ting; Li, Ping; Cheng, Ke

    2016-02-01

    This paper aims to present a theoretical method to study the bearing performance of vertically loaded large-diameter pipe pile groups. The interactions between group piles result in different bearing performance of both a single pile and pile groups. Considering the pile group effect and the skin friction from both outer and inner soils, an analytical solution is developed to calculate the settlement and axial force in large-diameter pipe pile groups. The analytical solution was verified by centrifuge and field testing results. An extensive parametric analysis was performed to study the bearing performance of the pipe pile groups. The results reveal that the axial forces in group piles are not the same. The larger the distance from central pile, the larger the axial force. The axial force in the central pile is the smallest, while that in corner piles is the largest. The axial force on the top of the corner piles decreases while that in the central pile increases with increasing of pile spacing and decreasing of pile length. The axial force in side piles varies little with the variations of pile spacing, pile length, and shear modulus of the soil and is approximately equal to the average load shared by one pile. For a pile group, the larger the pile length is, the larger the influence radius is. As a result, the pile group effect is more apparent for a larger pile length. The settlement of pile groups decreases with increasing of the pile number in the group and the shear modulus of the underlying soil.

  2. Action relevance in linguistic context drives word-induced motor activity

    PubMed Central

    Aravena, Pia; Courson, Mélody; Frak, Victor; Cheylus, Anne; Paulignan, Yves; Deprez, Viviane; Nazir, Tatjana A.

    2014-01-01

    Many neurocognitive studies on the role of motor structures in action-language processing have implicitly adopted a “dictionary-like” framework within which lexical meaning is constructed on the basis of an invariant set of semantic features. The debate has thus been centered on the question of whether motor activation is an integral part of the lexical semantics (embodied theories) or the result of a post-lexical construction of a situation model (disembodied theories). However, research in psycholinguistics show that lexical semantic processing and context-dependent meaning construction are narrowly integrated. An understanding of the role of motor structures in action-language processing might thus be better achieved by focusing on the linguistic contexts under which such structures are recruited. Here, we therefore analyzed online modulations of grip force while subjects listened to target words embedded in different linguistic contexts. When the target word was a hand action verb and when the sentence focused on that action (John signs the contract) an early increase of grip force was observed. No comparable increase was detected when the same word occurred in a context that shifted the focus toward the agent's mental state (John wants to sign the contract). There mere presence of an action word is thus not sufficient to trigger motor activation. Moreover, when the linguistic context set up a strong expectation for a hand action, a grip force increase was observed even when the tested word was a pseudo-verb. The presence of a known action word is thus not required to trigger motor activation. Importantly, however, the same linguistic contexts that sufficed to trigger motor activation with pseudo-verbs failed to trigger motor activation when the target words were verbs with no motor action reference. Context is thus not by itself sufficient to supersede an “incompatible” word meaning. We argue that motor structure activation is part of a dynamic process

  3. dsRNA Released by Tissue Damage Activates TLR3 to Drive Skin Regeneration.

    PubMed

    Nelson, Amanda M; Reddy, Sashank K; Ratliff, Tabetha S; Hossain, M Zulfiquer; Katseff, Adiya S; Zhu, Amadeus S; Chang, Emily; Resnik, Sydney R; Page, Carly; Kim, Dongwon; Whittam, Alexander J; Miller, Lloyd S; Garza, Luis A

    2015-08-01

    Regeneration of skin and hair follicles after wounding--a process known as wound-induced hair neogenesis (WIHN)--is a rare example of adult organogenesis in mammals. As such, WIHN provides a unique model system for deciphering mechanisms underlying mammalian regeneration. Here, we show that dsRNA, which is released from damaged skin, activates Toll-Like Receptor 3 (TLR3) and its downstream effectors IL-6 and STAT3 to promote hair follicle regeneration. Conversely, TLR3-deficient animals fail to initiate WIHN. TLR3 activation promotes expression of hair follicle stem cell markers and induces elements of the core hair morphogenetic program, including ectodysplasin A receptor (EDAR) and the Wnt and Shh pathways. Our results therefore show that dsRNA and TLR3 link the earliest events of mammalian skin wounding to regeneration and suggest potential therapeutic approaches for promoting hair neogenesis. PMID:26253200

  4. BMP7 drives human adipogenic stem cells into metabolically active beige adipocytes

    PubMed Central

    Okla, Meshail; Ha, Jung-Heun; Temel, Ryan E.; Chung, Soonkyu

    2014-01-01

    Adult humans have a substantial amount of inducible-brown (or beige) fat, which is associated with increased energy expenditure and reduced weight gain via thermogenesis. Despite the identification of key regulators of beige adipogenesis, impacts of dietary factors on adaptive thermogenesis are largely unknown, partly due to a lack of validated human cell models. Bone morphogenetic protein 7 (BMP7) is known to promote brown adipogenesis in rodent and human progenitor cells. However, controversy still surrounds the cellular identity in BMP7-mediated transition of white to brown adipocytes. The aim of this study is to confirm BMP7-derived human adipocytes as a relevant in vitro model of human beige adipocyte by verifying the cellular lineage and metabolic activity. In this study, we hypothesized that pre-exposure of stromal vascular (SV) fraction of primary human adipogenic precursor cells (hASC) to BMP7 would convert metabolically active brown adipocytes. Our results showed that exposure of hASC to human BMP7 was associated with significant escalation of 1) UCP1 gene expression, a signature gene of brown adipocytes, 2) beige specific marker gene expression (i.e., CD137 and TMEM26), 3) glucose and fatty acid uptake, and 4) basal and cAMP-stimulated oxygen consumption rate compared to white adipocyte control. Taken together, we demonstrated that BMP7 mediates conversion of hASC into metabolically active beige adipocytes. By confirming the cellular identity and metabolic activity, this BMP7-induced human beige adipocytes from hASC should aid in the discovery and assessment of bioactive molecules to promote adaptive thermogenesis. PMID:25534037

  5. BMP7 drives human adipogenic stem cells into metabolically active beige adipocytes.

    PubMed

    Okla, Meshail; Ha, Jung-Heun; Temel, Ryan E; Chung, Soonkyu

    2015-02-01

    Adult humans have a substantial amount of inducible-brown (or beige) fat, which is associated with increased energy expenditure and reduced weight gain via thermogenesis. Despite the identification of key regulators of beige adipogenesis, impacts of dietary factors on adaptive thermogenesis are largely unknown, partly due to a lack of validated human cell models. Bone morphogenetic protein 7 (BMP7) is known to promote brown adipogenesis in rodent and human progenitor cells. However, controversy still surrounds the cellular identity in BMP7-mediated transition of white to brown adipocytes. The aim of this study was to confirm BMP7-derived human adipocytes as a relevant in vitro model of human beige adipocyte by verifying the cellular lineage and metabolic activity. In this study, we hypothesized that pre-exposure of the stromal vascular (SV) fraction of primary human adipogenic precursor cells (hASC) to BMP7 would convert metabolically active brown adipocytes. Our results showed that exposure of hASC to human BMP7 was associated with significant escalation of (1) UCP1 gene expression, a signature gene of brown adipocytes, (2) beige specific marker gene expression (i.e., CD137 and TMEM26), (3) glucose and fatty acid uptake, and (4) basal and cAMP-stimulated oxygen consumption rate compared to white adipocyte control. Taken together, we demonstrated that BMP7 mediates conversion of hASC into metabolically active beige adipocytes. By confirming the cellular identity and metabolic activity, this BMP7-induced human beige adipocytes from hASC should aid in the discovery and assessment of bioactive molecules to promote adaptive thermogenesis. PMID:25534037

  6. Conversion of abiraterone to D4A drives antitumor activity in prostate cancer

    PubMed Central

    Li, Zhenfei; Bishop, Andrew; Alyamani, Mohammad; Garcia, Jorge A.; Dreicer, Robert; Bunch, Dustin; Liu, Jiayan; Upadhyay, Sunil K.; Auchus, Richard J.; Sharifi, Nima

    2015-01-01

    Summary Prostate cancer resistance to castration occurs because tumors acquire the metabolic capability of converting precursor steroids to 5α-dihydrotestosterone (DHT), promoting signaling by the androgen receptor (AR) and the development of castration-resistant prostate cancer (CRPC)1–3. Essential for resistance, DHT synthesis from adrenal precursor steroids or possibly from de novo synthesis from cholesterol commonly require enzymatic reactions by 3β-hydroxysteroid dehydrogenase (3βHSD), steroid-5α-reductase (SRD5A) and 17β-hydroxysteroid dehydrogenase (17βHSD) isoenzymes4,5. Abiraterone, a steroidal 17α-hydroxylase/17,20-lyase (CYP17A1) inhibitor, blocks this synthetic process and prolongs survival6,7. We hypothesized that abiraterone is converted by an enzyme to the more active Δ4-abiraterone (D4A) that blocks multiple steroidogenic enzymes and antagonizes the androgen receptor (AR), providing an additional explanation for abiraterone’s clinical activity. Here we show that abiraterone is converted to D4A in mice and patients with prostate cancer. D4A inhibits CYP17A1, 3βHSD and SRD5A, which are required for DHT synthesis. Furthermore, competitive AR antagonism by D4A is comparable to the potent antagonist, enzalutamide. D4A also has more potent antitumor activity against xenograft tumors than abiraterone. Our findings suggest an additional explanation – conversion to a more active agent – for abiraterone’s survival extension. We propose that direct treatment with D4A would be more clinically effective than abiraterone treatment. PMID:26030522

  7. F-actin polymerization and retrograde flow drive sustained PLCγ1 signaling during T cell activation

    PubMed Central

    Babich, Alexander; Li, Shuixing; O'Connor, Roddy S.; Milone, Michael C.; Freedman, Bruce D.

    2012-01-01

    Activation of T cells by antigen-presenting cells involves assembly of signaling molecules into dynamic microclusters (MCs) within a specialized membrane domain termed the immunological synapse (IS). Actin and myosin IIA localize to the IS, and depletion of F-actin abrogates MC movement and T cell activation. However, the mechanisms that coordinate actomyosin dynamics and T cell receptor signaling are poorly understood. Using pharmacological inhibitors that perturb individual aspects of actomyosin dynamics without disassembling the network, we demonstrate that F-actin polymerization is the primary driver of actin retrograde flow, whereas myosin IIA promotes long-term integrity of the IS. Disruption of F-actin retrograde flow, but not myosin IIA contraction, arrested MC centralization and inhibited sustained Ca2+ signaling at the level of endoplasmic reticulum store release. Furthermore, perturbation of retrograde flow inhibited PLCγ1 phosphorylation within MCs but left Zap70 activity intact. These studies highlight the importance of ongoing actin polymerization as a central driver of actomyosin retrograde flow, MC centralization, and sustained Ca2+ signaling. PMID:22665519

  8. Phasic dopamine release drives rapid activation of striatal D2-receptors

    PubMed Central

    Marcott, Pamela F; Mamaligas, Aphroditi A; Ford, Christopher P

    2014-01-01

    Summary Striatal dopamine transmission underlies numerous goal-directed behaviors. Medium spiny neurons (MSNs) are a major target of dopamine in the striatum. However, as dopamine does not directly evoke a synaptic event in MSNs, the time course of dopamine signaling in these cells remains unclear. To examine how dopamine release activates D2-receptors on MSNs, G-protein activated inwardly rectifying potassium (GIRK2; Kir 3.2) channels were virally overexpressed in the striatum and the resulting outward currents were used as a sensor of D2-receptor activation. Electrical and optogenetic stimulation of dopamine terminals evoked robust D2-receptor inhibitory post-synaptic currents (IPSCs) in GIRK2-expressing MSNs that occurred in under a second. Evoked D2-IPSCs could be driven by repetitive stimulation and were not occluded by background dopamine tone. Together, the results indicate that D2-receptors on MSNs exhibit functional low affinity and suggest that striatal D2-receptors can encode both tonic and phasic dopamine signals. PMID:25242218

  9. Activating Receptor Signals Drive Receptor Diversity in Developing Natural Killer Cells.

    PubMed

    Freund, Jacquelyn; May, Rebecca M; Yang, Enjun; Li, Hongchuan; McCullen, Matthew; Zhang, Bin; Lenvik, Todd; Cichocki, Frank; Anderson, Stephen K; Kambayashi, Taku

    2016-08-01

    It has recently been appreciated that NK cells exhibit many features reminiscent of adaptive immune cells. Considerable heterogeneity exists with respect to the ligand specificity of individual NK cells and as such, a subset of NK cells can respond, expand, and differentiate into memory-like cells in a ligand-specific manner. MHC I-binding inhibitory receptors, including those belonging to the Ly49 and KIR families, are expressed in a variegated manner, which creates ligand-specific diversity within the NK cell pool. However, how NK cells determine which inhibitory receptors to express on their cell surface during a narrow window of development is largely unknown. In this manuscript, we demonstrate that signals from activating receptors are critical for induction of Ly49 and KIR receptors during NK cell development; activating receptor-derived signals increased the probability of the Ly49 bidirectional Pro1 promoter to transcribe in the forward versus the reverse direction, leading to stable expression of Ly49 receptors in mature NK cells. Our data support a model where the balance of activating and inhibitory receptor signaling in NK cells selects for the induction of appropriate inhibitory receptors during development, which NK cells use to create a diverse pool of ligand-specific NK cells. PMID:27500644

  10. ADAR1 Activation Drives Leukemia Stem Cell Self-Renewal by Impairing Let-7 Biogenesis.

    PubMed

    Zipeto, Maria Anna; Court, Angela C; Sadarangani, Anil; Delos Santos, Nathaniel P; Balaian, Larisa; Chun, Hye-Jung; Pineda, Gabriel; Morris, Sheldon R; Mason, Cayla N; Geron, Ifat; Barrett, Christian; Goff, Daniel J; Wall, Russell; Pellecchia, Maurizio; Minden, Mark; Frazer, Kelly A; Marra, Marco A; Crews, Leslie A; Jiang, Qingfei; Jamieson, Catriona H M

    2016-08-01

    Post-transcriptional adenosine-to-inosine RNA editing mediated by adenosine deaminase acting on RNA1 (ADAR1) promotes cancer progression and therapeutic resistance. However, ADAR1 editase-dependent mechanisms governing leukemia stem cell (LSC) generation have not been elucidated. In blast crisis chronic myeloid leukemia (BC CML), we show that increased JAK2 signaling and BCR-ABL1 amplification activate ADAR1. In a humanized BC CML mouse model, combined JAK2 and BCR-ABL1 inhibition prevents LSC self-renewal commensurate with ADAR1 downregulation. Lentiviral ADAR1 wild-type, but not an editing-defective ADAR1(E912A) mutant, induces self-renewal gene expression and impairs biogenesis of stem cell regulatory let-7 microRNAs. Combined RNA sequencing, qRT-PCR, CLIP-ADAR1, and pri-let-7 mutagenesis data suggest that ADAR1 promotes LSC generation via let-7 pri-microRNA editing and LIN28B upregulation. A small-molecule tool compound antagonizes ADAR1's effect on LSC self-renewal in stromal co-cultures and restores let-7 biogenesis. Thus, ADAR1 activation represents a unique therapeutic vulnerability in LSCs with active JAK2 signaling. PMID:27292188

  11. RAC1 activation drives pathologic interactions between the epidermis and immune cells.

    PubMed

    Winge, Mårten C G; Ohyama, Bungo; Dey, Clara N; Boxer, Lisa M; Li, Wei; Ehsani-Chimeh, Nazanin; Truong, Allison K; Wu, Diane; Armstrong, April W; Makino, Teruhiko; Davidson, Matthew; Starcevic, Daniela; Kislat, Andreas; Nguyen, Ngon T; Hashimoto, Takashi; Homey, Bernard; Khavari, Paul A; Bradley, Maria; Waterman, Elizabeth A; Marinkovich, M Peter

    2016-07-01

    Interactions between the epidermis and the immune system govern epidermal tissue homeostasis. These epidermis-immune interactions are altered in the inflammatory disease psoriasis; however, the pathways that underlie this aberrant immune response are not well understood. Here, we determined that Ras-related C3 botulinum toxin substrate 1 (RAC1) is a key mediator of epidermal dysfunction. RAC1 activation was consistently elevated in psoriatic epidermis and primary psoriatic human keratinocytes (PHKCs) exposed to psoriasis-related stimuli, but not in skin from patients with basal or squamous cell carcinoma. Expression of a constitutively active form of RAC1 (RACV12) in mice resulted in the development of lesions similar to those of human psoriasis that required the presence of an intact immune system. RAC1V12-expressing mice and human psoriatic skin showed similar RAC1-dependent signaling as well as transcriptional overlap of differentially expressed epidermal and immune pathways. Coculture of PHKCs with immunocytes resulted in the upregulation of RAC1-dependent proinflammatory cytokines, an effect that was reproduced by overexpressing RAC1 in normal human keratinocytes. In keratinocytes, modulating RAC1 activity altered differentiation, proliferation, and inflammatory pathways, including STAT3, NFκB, and zinc finger protein 750 (ZNF750). Finally, RAC1 inhibition in xenografts composed of human PHKCs and immunocytes abolished psoriasiform hyperplasia and inflammation in vivo. These studies implicate RAC1 as a potential therapeutic target for psoriasis and as a key orchestrator of pathologic epidermis-immune interactions. PMID:27294528

  12. Activating Receptor Signals Drive Receptor Diversity in Developing Natural Killer Cells

    PubMed Central

    Freund, Jacquelyn; May, Rebecca M.; Li, Hongchuan; McCullen, Matthew; Zhang, Bin; Lenvik, Todd; Cichocki, Frank; Anderson, Stephen K.; Kambayashi, Taku

    2016-01-01

    It has recently been appreciated that NK cells exhibit many features reminiscent of adaptive immune cells. Considerable heterogeneity exists with respect to the ligand specificity of individual NK cells and as such, a subset of NK cells can respond, expand, and differentiate into memory-like cells in a ligand-specific manner. MHC I-binding inhibitory receptors, including those belonging to the Ly49 and KIR families, are expressed in a variegated manner, which creates ligand-specific diversity within the NK cell pool. However, how NK cells determine which inhibitory receptors to express on their cell surface during a narrow window of development is largely unknown. In this manuscript, we demonstrate that signals from activating receptors are critical for induction of Ly49 and KIR receptors during NK cell development; activating receptor-derived signals increased the probability of the Ly49 bidirectional Pro1 promoter to transcribe in the forward versus the reverse direction, leading to stable expression of Ly49 receptors in mature NK cells. Our data support a model where the balance of activating and inhibitory receptor signaling in NK cells selects for the induction of appropriate inhibitory receptors during development, which NK cells use to create a diverse pool of ligand-specific NK cells. PMID:27500644

  13. Do Polyethylene Plastic Covers Affect Smoke Emissions from Debris Piles?

    NASA Astrophysics Data System (ADS)

    Weise, D. R.; Jung, H.; Cocker, D.; Hosseini, E.; Li, Q.; Shrivastava, M.; McCorison, M.

    2010-12-01

    Shrubs and small diameter trees exist in the understories of many western forests. They are important from an ecological perspective; however, this vegetation also presents a potential hazard as “ladder fuels” or as a heat source to damage the overstory during prescribed burns. Cutting and piling of this material to burn under safe conditions is a common silvicultural practice. To improve ignition success of the piled debris, polyethylene plastic is often used to cover a portion of the pile. While burning of piled forest debris is an acceptable practice in southern California from an air quality perspective, inclusion of plastic in the piles changes these debris piles to rubbish piles which should not be burned. With support from the four National Forests in southern California, we conducted a laboratory experiment to determine if the presence of polyethylene plastic in a pile of burning wood changed the smoke emissions. Debris piles in southern California include wood and foliage from common forest trees such as sugar and ponderosa pines, white fir, incense cedar, and California black oak and shrubs such as ceanothus and manzanita in addition to forest floor material and dirt. Manzanita wood was used to represent the debris pile in order to control the effects of fuel bed composition. The mass of polyethylene plastic incorporated into the pile was 0, 0.25 and 2.5% of the wood mass—a range representative of field conditions. Measured emissions included NOx, CO, CO2, SO2, polycyclic and light hydrocarbons, carbonyls, particulate matter (5 to 560 nm), elemental and organic carbon. The presence of polyethylene did not alter the emissions composition from this experiment.

  14. Changes in aspen bark stored in outdoor piles

    SciTech Connect

    Zoch, E.L.; Rusch, J.J.; Springer, E.L.

    1982-06-01

    Increasing use of bark for fuel has led to questions as to the losses and other changes that occur during outdoor pile storage. The possibility of spontaneous ignition in bark piles is of special concern. This study examined the storage characteristics of aspen bark. Two aspen bark piles, 40 feet by 40 feet by 20 feet high, were built in October of 1974 and 1975 at a northern Wisconsin mill site. The 1974 pile contained bark which came directly from a ring debarker; the 1975 pile was built using bark that had been put through a hammermill after it came from the ring debarker. Temperatures were observed at the centers of the piles using thermistors placed at 5, 10 and 15 feet above the base. Bark substance losses (ovendry material) were determined by placing bark samples contained in nylon mesh bags at each of these locations in each pile and retrieving them after 1 year of storage. Maximum pile tempreatures were attained in about 3 weeks and were about 160 degrees F for both piles. Bark substance losses varied with height above the base of the pile, being greatest at the 15-foot level (about 25%) and least at the 5-foot level (about 5%). Moisture content also varied with the height and was greatest at the 15-foot level. The pH of the bark decreased during storage from an initial value of 4.6 to final values ranging between 2.6 and 3.3. Bark particle size did not significantly affect pile temperatures, weight losses or changes in pH and moisture content. (Refs. 8).

  15. Driving reactions: Surmounting activation barriers in solid state chemistry using hydroxide melts and RF plasmas

    NASA Astrophysics Data System (ADS)

    Friedman, Todd Lawrence

    1997-11-01

    This thesis explores several techniques for surmounting activation barriers in solid state chemistry. The two major issues addressed are the use of a solution-based molten hydroxide system to increase the rate of reactant diffusion over that in the solid state, and the use of an RF plasma to break bonds in gaseous reactants for subsequent reaction with a solid. Part I describes the use of molten alkali metal hydroxides as a low-temperature solvent system for both electrodeposition and precipitation of high valent copper oxides. Cyclic voltammetry was used to determine the effects of various reaction conditions on copper dissolved in the melts, including copper activity, temperature, and atmosphere composition. The results of this study indicate that copper oxide phases become less soluble at higher copper activities, temperatures, and pHsb2O values. Also, the Cu(II)/Cu(III) redox wave, important for the electrodeposition of cuprate phases with high copper formal oxidation states, is observed below 300sp°C in air and at 350sp°C in dry argon. NaCuOsb2 was electrodeposited under constant current conditions. Iodometric titrations and annealing studies indicate that NaCuOsb2 is oxygen deficient and tends to lose additional oxygen on heating. The hydroxide method was also successful in the deposition of thin films of superconducting EuBasb2Cusb4Osb8 on SrTiOsb3 substrates. The films were found to be superconducting with a Tsbc of 75 K in the absence of annealing. In Part II, the idea of circumventing activation energy barriers is applied to the problem of environmentally harmful perfluorocarbons (PFCs). Mass spectrometry was used to determine the PFC emissions from two semiconductor manufacturing processes: oxide etch and post-CVD chamber clean. Because of radical recombination to thermodynamically stable species, most of the PFCs used in these processes are emitted to the atmosphere. A prototype abatement device which uses an RF plasma to provide the activation energy

  16. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... marking pile fabric as to fiber content provided for in this section are as follows: 100% Nylon Pile 100% Cotton Back (Back constitutes 60% of fabric and pile 40%). Face—60% Rayon, 40% Nylon Back—70% Cotton,...

  17. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... marking pile fabric as to fiber content provided for in this section are as follows: 100% Nylon Pile 100% Cotton Back (Back constitutes 60% of fabric and pile 40%). Face—60% Rayon, 40% Nylon Back—70% Cotton,...

  18. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... marking pile fabric as to fiber content provided for in this section are as follows: 100% Nylon Pile 100% Cotton Back (Back constitutes 60% of fabric and pile 40%). Face—60% Rayon, 40% Nylon Back—70% Cotton,...

  19. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... marking pile fabric as to fiber content provided for in this section are as follows: 100% Nylon Pile 100% Cotton Back (Back constitutes 60% of fabric and pile 40%). Face—60% Rayon, 40% Nylon Back—70% Cotton,...

  20. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... marking pile fabric as to fiber content provided for in this section are as follows: 100% Nylon Pile 100% Cotton Back (Back constitutes 60% of fabric and pile 40%). Face—60% Rayon, 40% Nylon Back—70% Cotton,...

  1. CCL2 Mediates Neuron-Macrophage Interactions to Drive Proregenerative Macrophage Activation Following Preconditioning Injury.

    PubMed

    Kwon, Min Jung; Shin, Hae Young; Cui, Yuexian; Kim, Hyosil; Thi, Anh Hong Le; Choi, Jun Young; Kim, Eun Young; Hwang, Dong Hoon; Kim, Byung Gon

    2015-12-01

    CNS neurons in adult mammals do not spontaneously regenerate axons after spinal cord injury. Preconditioning peripheral nerve injury allows the dorsal root ganglia (DRG) sensory axons to regenerate beyond the injury site by promoting expression of regeneration-associated genes. We have previously shown that peripheral nerve injury increases the number of macrophages in the DRGs and that the activated macrophages are critical to the enhancement of intrinsic regeneration capacity. The present study identifies a novel chemokine signal mediated by CCL2 that links regenerating neurons with proregenerative macrophage activation. Neutralization of CCL2 abolished the neurite outgrowth activity of conditioned medium obtained from neuron-macrophage cocultures treated with cAMP. The neuron-macrophage interactions that produced outgrowth-promoting conditioned medium required CCL2 in neurons and CCR2/CCR4 in macrophages. The conditioning effects were abolished in CCL2-deficient mice at 3 and 7 d after sciatic nerve injury, but CCL2 was dispensable for the initial growth response and upregulation of GAP-43 at the 1 d time point. Intraganglionic injection of CCL2 mimicked conditioning injury by mobilizing M2-like macrophages. Finally, overexpression of CCL2 in DRGs promoted sensory axon regeneration in a rat spinal cord injury model without harmful side effects. Our data suggest that CCL2-mediated neuron-macrophage interaction plays a critical role for amplification and maintenance of enhanced regenerative capacity by preconditioning peripheral nerve injury. Manipulation of chemokine signaling mediating neuron-macrophage interactions may represent a novel therapeutic approach to promote axon regeneration after CNS injury. PMID:26631474

  2. Minifilament Eruptions that Drive Coronal Jets in a Solar Active Region

    NASA Astrophysics Data System (ADS)

    Sterling, Alphonse C.; Moore, Ronald L.; Falconer, David A.; Panesar, Navdeep K.; Akiyama, Sachiko; Yashiro, Seiji; Gopalswamy, Nat

    2016-04-01

    We present observations of eruptive events in an active region adjacent to an on-disk coronal hole on 2012 June 30, primarily using data from the Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA), SDO/Helioseismic and Magnetic Imager (HMI), and STEREO-B. One eruption is of a large-scale (∼100″) filament that is typical of other eruptions, showing slow-rise onset followed by a faster-rise motion starting as flare emissions begin. It also shows an “EUV crinkle” emission pattern, resulting from magnetic reconnections between the exploding filament-carrying field and surrounding field. Many EUV jets, some of which are surges, sprays and/or X-ray jets, also occur in localized areas of the active region. We examine in detail two relatively energetic ones, accompanied by GOES M1 and C1 flares, and a weaker one without a GOES signature. All three jets resulted from small-scale (∼20″) filament eruptions consistent with a slow rise followed by a fast rise occurring with flare-like jet-bright-point brightenings. The two more-energetic jets showed crinkle patters, but the third jet did not, perhaps due to its weakness. Thus all three jets were consistent with formation via erupting minifilaments, analogous to large-scale filament eruptions and to X-ray jets in polar coronal holes. Several other energetic jets occurred in a nearby portion of the active region; while their behavior was also consistent with their source being minifilament eruptions, we could not confirm this because their onsets were hidden from our view. Magnetic flux cancelation and emergence are candidates for having triggered the minifilament eruptions.

  3. Perceived social pressures and the internalization of the mesomorphic ideal: The role of drive for muscularity and autonomy in physically active men.

    PubMed

    Edwards, Christian; Tod, David; Molnar, Gyozo; Markland, David

    2016-03-01

    We examined if there were both direct and indirect relationships (via the drive for muscularity) between the perceived pressure to be muscular and internalization of the mesomorphic ideal, and if autonomy moderates these relationships in physically active men. A sample of 330 men, who were undergraduate students studying sport, completed the Behavioral Regulation in Exercise Questionnaire-2, the Mesomorphic Ideal Internalization subscale of the revised male version Sociocultural Attitudes Toward Appearance Questionnaire, the Perceived Sociocultural Pressure Scale-Modified, and the Drive for Muscularity Scale Attitudes subscale. Perceived pressure predicted internalization directly, and indirectly through the drive for muscularity. The direct relationship between pressure and internalization was weaker under higher levels of autonomy. The indirect path, via drive for muscularity, was stronger under higher levels of autonomy. These results provide insights into why men vary in the degree to which they internalize pressure to develop a mesomorphic ideal, supporting further examination of autonomy. PMID:26688273

  4. The Musculature That Drives Active Touch by Vibrissae and Nose in Mice.

    PubMed

    Haidarliu, Sebastian; Kleinfeld, David; Deschênes, Martin; Ahissar, Ehud

    2015-07-01

    Coordinated action of facial muscles during whisking, sniffing, and touching objects is an important component of active sensing in rodents. Accumulating evidence suggests that the anatomical schemes that underlie active sensing are similar across the majority of whisking rodents. Intriguingly, however, muscle architecture in the mystacial pad of the mouse was reported to be different, possessing only one extrinsic vibrissa protracting muscle (M. nasalis) in the rostral part of the snout. In this study, the organization of the muscles that move the nose and the mystacial vibrissae in mice was re-examined and compared with that reported previously in other rodents. We found that muscle distribution within the mystacial pad and around the tip of the nose in mice is isomorphic with that found in other whisking rodents. In particular, in the rostral part of the mouse snout, we describe both protractors and retractors of the vibrissae. Nose movements are controlled by the M. dilator nasi and five subunits of the M. nasolabialis profundus, with involvement of the nasal cartilaginous skeleton as a mediator in the muscular effort translation. PMID:25408106

  5. Nucleotide-induced asymmetry within ATPase activator ring drives σ54-RNAP interaction and ATP hydrolysis

    SciTech Connect

    Sysoeva, Tatyana A.; Chowdhury, Saikat; Guo, Liang; Nixon, B. Tracy

    2013-12-10

    It is largely unknown how the typical homomeric ring geometry of ATPases associated with various cellular activities enables them to perform mechanical work. Small-angle solution X-ray scattering, crystallography, and electron microscopy (EM) reconstructions revealed that partial ATP occupancy caused the heptameric closed ring of the bacterial enhancer-binding protein (bEBP) NtrC1 to rearrange into a hexameric split ring of striking asymmetry. The highly conserved and functionally crucial GAFTGA loops responsible for interacting with σ54–RNA polymerase formed a spiral staircase. We propose that splitting of the ensemble directs ATP hydrolysis within the oligomer, and the ring's asymmetry guides interaction between ATPase and the complex of σ54 and promoter DNA. Similarity between the structure of the transcriptional activator NtrC1 and those of distantly related helicases Rho and E1 reveals a general mechanism in homomeric ATPases whereby complex allostery within the ring geometry forms asymmetric functional states that allow these biological motors to exert directional forces on their target macromolecules.

  6. Enhanced dimerization drives ligand-independent activity of mutant epidermal growth factor receptor in lung cancer

    PubMed Central

    Valley, Christopher C.; Arndt-Jovin, Donna J.; Karedla, Narain; Steinkamp, Mara P.; Chizhik, Alexey I.; Hlavacek, William S.; Wilson, Bridget S.; Lidke, Keith A.; Lidke, Diane S.

    2015-01-01

    Mutations within the epidermal growth factor receptor (EGFR/erbB1/Her1) are often associated with tumorigenesis. In particular, a number of EGFR mutants that demonstrate ligand-independent signaling are common in non–small cell lung cancer (NSCLC), including kinase domain mutations L858R (also called L834R) and exon 19 deletions (e.g., ΔL747-P753insS), which collectively make up nearly 90% of mutations in NSCLC. The molecular mechanisms by which these mutations confer constitutive activity remain unresolved. Using multiple subdiffraction-limit imaging modalities, we reveal the altered receptor structure and interaction kinetics of NSCLC-associated EGFR mutants. We applied two-color single quantum dot tracking to quantify receptor dimerization kinetics on living cells and show that, in contrast to wild-type EGFR, mutants are capable of forming stable, ligand-independent dimers. Two-color superresolution localization microscopy confirmed ligand-independent aggregation of EGFR mutants. Live-cell Förster resonance energy transfer measurements revealed that the L858R kinase mutation alters ectodomain structure such that unliganded mutant EGFR adopts an extended, dimerization-competent conformation. Finally, mutation of the putative dimerization arm confirmed a critical role for ectodomain engagement in ligand-independent signaling. These data support a model in which dysregulated activity of NSCLC-associated kinase mutants is driven by coordinated interactions involving both the kinase and extracellular domains that lead to enhanced dimerization. PMID:26337388

  7. Evolution of Muscle Activity Patterns Driving Motions of the Jaw and Hyoid during Chewing in Gnathostomes

    PubMed Central

    Konow, Nicolai; Herrel, Anthony; Ross, Callum F.; Williams, Susan H.; German, Rebecca Z.; Sanford, Christopher P. J.; Gintof, Chris

    2011-01-01

    Although chewing has been suggested to be a basal gnathostome trait retained in most major vertebrate lineages, it has not been studied broadly and comparatively across vertebrates. To redress this imbalance, we recorded EMG from muscles powering anteroposterior movement of the hyoid, and dorsoventral movement of the mandibular jaw during chewing. We compared muscle activity patterns (MAP) during chewing in jawed vertebrate taxa belonging to unrelated groups of basal bony fishes and artiodactyl mammals. Our aim was to outline the evolution of coordination in MAP. Comparisons of activity in muscles of the jaw and hyoid that power chewing in closely related artiodactyls using cross-correlation analyses identified reorganizations of jaw and hyoid MAP between herbivores and omnivores. EMG data from basal bony fishes revealed a tighter coordination of jaw and hyoid MAP during chewing than seen in artiodactyls. Across this broad phylogenetic range, there have been major structural reorganizations, including a reduction of the bony hyoid suspension, which is robust in fishes, to the acquisition in a mammalian ancestor of a muscle sling suspending the hyoid. These changes appear to be reflected in a shift in chewing MAP that occurred in an unidentified anamniote stem-lineage. This shift matches observations that, when compared with fishes, the pattern of hyoid motion in tetrapods is reversed and also time-shifted relative to the pattern of jaw movement. PMID:21705368

  8. Thalamocortical Connections Drive Intracortical Activation of Functional Columns in the Mislaminated Reeler Somatosensory Cortex.

    PubMed

    Wagener, Robin J; Witte, Mirko; Guy, Julien; Mingo-Moreno, Nieves; Kügler, Sebastian; Staiger, Jochen F

    2016-02-01

    Neuronal wiring is key to proper neural information processing. Tactile information from the rodent's whiskers reaches the cortex via distinct anatomical pathways. The lemniscal pathway relays whisking and touch information from the ventral posteromedial thalamic nucleus to layer IV of the primary somatosensory "barrel" cortex. The disorganized neocortex of the reeler mouse is a model system that should severely compromise the ingrowth of thalamocortical axons (TCAs) into the cortex. Moreover, it could disrupt intracortical wiring. We found that neuronal intermingling within the reeler barrel cortex substantially exceeded previous descriptions, leading to the loss of layers. However, viral tracing revealed that TCAs still specifically targeted transgenically labeled spiny layer IV neurons. Slice electrophysiology and optogenetics proved that these connections represent functional synapses. In addition, we assessed intracortical activation via immediate-early-gene expression resulting from a behavioral exploration task. The cellular composition of activated neuronal ensembles suggests extensive similarities in intracolumnar information processing in the wild-type and reeler brains. We conclude that extensive ectopic positioning of neuronal partners can be compensated for by cell-autonomous mechanisms that allow for the establishment of proper connectivity. Thus, genetic neuronal fate seems to be of greater importance for correct cortical wiring than radial neuronal position. PMID:26564256

  9. Stimulation of Na(+),K(+)-ATPase Activity as a Possible Driving Force in Cholesterol Evolution.

    PubMed

    Lambropoulos, Nicholas; Garcia, Alvaro; Clarke, Ronald J

    2016-06-01

    Cholesterol is exclusively produced by animals and is present in the plasma membrane of all animal cells. In contrast, the membranes of fungi and plants contain other sterols. To explain the exclusive preference of animal cells for cholesterol, we propose that cholesterol may have evolved to optimize the activity of a crucial protein found in the plasma membrane of all multicellular animals, namely the Na(+),K(+)-ATPase. To test this hypothesis, mirror tree and phylogenetic distribution analyses have been conducted of the Na(+),K(+)-ATPase and 3β-hydroxysterol Δ(24)-reductase (DHCR24), the last enzyme in the Bloch cholesterol biosynthetic pathway. The results obtained support the hypothesis of a co-evolution of the Na(+),K(+)-ATPase and DHCR24. The evolutionary correlation between DHCR24 and the Na(+),K(+)-ATPase was found to be stronger than between DHCR24 and any other membrane protein investigated. The results obtained, thus, also support the hypothesis that cholesterol evolved together with the Na(+),K(+)-ATPase in multicellular animals to support Na(+),K(+)-ATPase activity. PMID:26715509

  10. Activating mutations in the NT5C2 nucleotidase gene drive chemotherapy resistance in relapsed ALL

    PubMed Central

    Tzoneva, Gannie; Garcia, Arianne Perez; Carpenter, Zachary; Khiabanian, Hossein; Tosello, Valeria; Allegretta, Maddalena; Paietta, Elisabeth; Racevskis, Janis; Rowe, Jacob M.; Tallman, Martin S.; Paganin, Maddalena; Basso, Giuseppe; Hof, Jana; Kirschner-Schwabe, Renate; Palomero, Teresa; Rabadan, Raul; Ferrando, Adolfo

    2013-01-01

    Acute lymphoblastic leukemia (ALL) is an aggressive hematological tumor resulting from the malignant transformation of lymphoid progenitors. Despite intensive chemotherapy, 20% of pediatric and over 50% of adult ALL patients fail to achieve a complete remission or relapse after intensified chemotherapy, making disease relapse and resistance to therapy the most significant challenge in the treatment of this disease1,2. Using whole exome sequencing, here we identify mutations in the cytosolic 5'-nucleotidase II gene (NT5C2), which encodes a 5'-nucleotidase enzyme responsible for inactivation of nucleoside analog chemotherapy drugs, in 20/103 (19%) relapse T-ALLs and in 1/35 (3%) relapse B-precursor ALLs analyzed. NT5C2 mutant proteins show increased nucleotidase activity in vitro and conferred resistance to chemotherapy with 6-mercaptopurine and 6-thioguanine when expressed in ALL lymphoblasts. These results support a prominent role for activating mutations in NT5C2 and increased nucleoside analog metabolism in disease progression and chemotherapy resistance in ALL. PMID:23377281

  11. Thalamocortical Connections Drive Intracortical Activation of Functional Columns in the Mislaminated Reeler Somatosensory Cortex

    PubMed Central

    Wagener, Robin J.; Witte, Mirko; Guy, Julien; Mingo-Moreno, Nieves; Kügler, Sebastian; Staiger, Jochen F.

    2016-01-01

    Neuronal wiring is key to proper neural information processing. Tactile information from the rodent's whiskers reaches the cortex via distinct anatomical pathways. The lemniscal pathway relays whisking and touch information from the ventral posteromedial thalamic nucleus to layer IV of the primary somatosensory “barrel” cortex. The disorganized neocortex of the reeler mouse is a model system that should severely compromise the ingrowth of thalamocortical axons (TCAs) into the cortex. Moreover, it could disrupt intracortical wiring. We found that neuronal intermingling within the reeler barrel cortex substantially exceeded previous descriptions, leading to the loss of layers. However, viral tracing revealed that TCAs still specifically targeted transgenically labeled spiny layer IV neurons. Slice electrophysiology and optogenetics proved that these connections represent functional synapses. In addition, we assessed intracortical activation via immediate-early-gene expression resulting from a behavioral exploration task. The cellular composition of activated neuronal ensembles suggests extensive similarities in intracolumnar information processing in the wild-type and reeler brains. We conclude that extensive ectopic positioning of neuronal partners can be compensated for by cell-autonomous mechanisms that allow for the establishment of proper connectivity. Thus, genetic neuronal fate seems to be of greater importance for correct cortical wiring than radial neuronal position. PMID:26564256

  12. Activated WNT signaling in postnatal SOX2-positive dental stem cells can drive odontoma formation

    PubMed Central

    Xavier, Guilherme M.; Patist, Amanda L.; Healy, Chris; Pagrut, Ankita; Carreno, Gabriela; Sharpe, Paul T.; Pedro Martinez-Barbera, Juan; Thavaraj, Selvam; Cobourne, Martyn T.; Andoniadou, Cynthia L.

    2015-01-01

    In common with most mammals, humans form only two dentitions during their lifetime. Occasionally, supernumerary teeth develop in addition to the normal complement. Odontoma represent a small group of malformations containing calcified dental tissues of both epithelial and mesenchymal origin, with varying levels of organization, including tooth-like structures. The specific cell type responsible for the induction of odontoma, which retains the capacity to re-initiate de novo tooth development in postnatal tissues, is not known. Here we demonstrate that aberrant activation of WNT signaling by expression of a non-degradable form of β-catenin specifically in SOX2-positive postnatal dental epithelial stem cells is sufficient to generate odontoma containing multiple tooth-like structures complete with all dental tissue layers. Genetic lineage-tracing confirms that odontoma form in a similar manner to normal teeth, derived from both the mutation-sustaining epithelial stem cells and adjacent mesenchymal tissues. Activation of the WNT pathway in embryonic SOX2-positive progenitors results in ectopic expression of secreted signals that promote odontogenesis throughout the oral cavity. Significantly, the inductive potential of epithelial dental stem cells is retained in postnatal tissues, and up-regulation of WNT signaling specifically in these cells is sufficient to promote generation and growth of ectopic malformations faithfully resembling human odontoma. PMID:26411543

  13. Optogenetic Activation of a Lateral Hypothalamic-Ventral Tegmental Drive-Reward Pathway

    PubMed Central

    Gigante, Eduardo D.; Benaliouad, Faiza; Zamora-Olivencia, Veronica; Wise, Roy A.

    2016-01-01

    Electrical stimulation of the lateral hypothalamus can motivate feeding or can serve as a reward in its own right. It remains unclear whether the same or independent but anatomically overlapping circuitries mediate the two effects. Electrical stimulation findings implicate medial forebrain bundle (MFB) fibers of passage in both effects, and optogenetic studies confirm a contribution from fibers originating in the lateral hypothalamic area and projecting to or through the ventral tegmental area. Here we report that optogenetic activation of ventral tegmental fibers from cells of origin in more anterior or posterior portions of the MFB failed to induce either reward or feeding. The feeding and reward induced by optogenetic activation of fibers from the lateral hypothalamic cells of origin were influenced similarly by variations in stimulation pulse width and pulse frequency, consistent with the hypothesis of a common substrate for the two effects. There were, however, several cases where feeding but not self-stimulation or self-stimulation but not feeding were induced, consistent with the hypothesis that distinct but anatomically overlapping systems mediate the two effects. Thus while optogenetic stimulation provides a more selective tool for characterizing the mechanisms of stimulation-induced feeding and reward, it does not yet resolve the question of common or independent substrates. PMID:27387668

  14. Activated WNT signaling in postnatal SOX2-positive dental stem cells can drive odontoma formation.

    PubMed

    Xavier, Guilherme M; Patist, Amanda L; Healy, Chris; Pagrut, Ankita; Carreno, Gabriela; Sharpe, Paul T; Martinez-Barbera, Juan Pedro; Thavaraj, Selvam; Cobourne, Martyn T; Andoniadou, Cynthia L

    2015-01-01

    In common with most mammals, humans form only two dentitions during their lifetime. Occasionally, supernumerary teeth develop in addition to the normal complement. Odontoma represent a small group of malformations containing calcified dental tissues of both epithelial and mesenchymal origin, with varying levels of organization, including tooth-like structures. The specific cell type responsible for the induction of odontoma, which retains the capacity to re-initiate de novo tooth development in postnatal tissues, is not known. Here we demonstrate that aberrant activation of WNT signaling by expression of a non-degradable form of β-catenin specifically in SOX2-positive postnatal dental epithelial stem cells is sufficient to generate odontoma containing multiple tooth-like structures complete with all dental tissue layers. Genetic lineage-tracing confirms that odontoma form in a similar manner to normal teeth, derived from both the mutation-sustaining epithelial stem cells and adjacent mesenchymal tissues. Activation of the WNT pathway in embryonic SOX2-positive progenitors results in ectopic expression of secreted signals that promote odontogenesis throughout the oral cavity. Significantly, the inductive potential of epithelial dental stem cells is retained in postnatal tissues, and up-regulation of WNT signaling specifically in these cells is sufficient to promote generation and growth of ectopic malformations faithfully resembling human odontoma. PMID:26411543

  15. The musculature that drives active touch by vibrissae and nose in mice

    PubMed Central

    Haidarliu, Sebastian; Kleinfeld, David; Deschênes, Martin; Ahissar, Ehud

    2016-01-01

    Coordinated action of facial muscles during whisking, sniffing and touching objects is an important component of active sensing in rodents. Accumulating evidence suggests that the anatomical schemes that underlie active sensing are similar across the majority of whisking rodents. Intriguingly, however, muscle architecture in the mystacial pad (MP) of the mouse was reported to be different, possessing only one extrinsic vibrissa protracting muscle (M. nasalis) in the rostral part of the snout. In the present study, the organization of the muscles that move the nose and the mystacial vibrissae in mice was re-examined and compared with that reported previously in other rodents. We found that muscle distribution within the MP and around the tip of the nose in mice is isomorphic to that found in other whisking rodents. In particular, in the rostral part of the mouse snout, we describe both protractors and retractors of the vibrissae. Nose movements are controlled by the M. dilator nasi and five subunits of the M. nasolabialis profundus, with involvement of the nasal cartilaginous skeleton as a mediator in the muscular effort translation. PMID:25408106

  16. NEET In-Pile Ultrasonic Sensor Enablement-FY 2012 Status Report

    SciTech Connect

    JE Daw; JL Rempe; BR Tittmann; B Reinhardt; P Ramuhalli; R Montgomery; HT Chien

    2012-09-01

    Several Department Of Energy-Nuclear Energy (DOE-NE) programs, such as the Fuel Cycle Research and Development, Advanced Reactor Concepts, Light Water Reactor Sustainability, and Next Generation Nuclear Plant programs, are investigating new fuels and materials for advanced and existing reactors. A key objective of such programs is to understand the performance of these fuels and materials when irradiated. The Nuclear Energy Enabling Technology (NEET) Advanced Sensors and Instrumentation (ASI) in-pile instrumentation development activities are focused upon addressing cross-cutting needs for DOE-NE irradiation testing by providing higher fidelity, real-time data, with increased accuracy and resolution from smaller, compact sensors that are less intrusive. Ultrasonic technologies offer the potential to measure a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes, under harsh irradiation test conditions. There are two primary issues associated with in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. Due to the harsh nature of in-pile testing, and the range of measurements that are desired, an enhanced signal processing capability is needed to make in-pile ultrasonic sensors viable. This project addresses these technology deployment issues.

  17. Sigma factor RpoN (σ54) regulates pilE transcription in commensal Neisseria elongata.

    PubMed

    Rendón, María A; Hockenberry, Alyson M; McManus, Steven A; So, Magdalene

    2013-10-01

    Human-adapted Neisseria includes two pathogens, Neisseria gonorrhoeae and Neisseria meningitidis, and at least 13 species of commensals that colonize many of the same niches as the pathogens. The Type IV pilus plays an important role in the biology of pathogenic Neisseria. In these species, Sigma factor RpoD (σ(70)), Integration Host Factor, and repressors RegF and CrgA regulate transcription of pilE, the gene encoding the pilus structural subunit. The Type IV pilus is also a strictly conserved trait in commensal Neisseria. We present evidence that a different mechanism regulates pilE transcription in commensals. Using Neisseria elongata as a model, we show that Sigma factor RpoN (σ(54)), Integration Host Factor, and an activator we name Npa regulate pilE transcription. Taken in context with previous reports, our findings indicate pilE regulation switched from an RpoN- to an RpoD-dependent mechanism as pathogenic Neisseria diverged from commensals during evolution. Our findings have implications for the timing of Tfp expression and Tfp-mediated host cell interactions in these two groups of bacteria. PMID:23899162

  18. Induction Motor Drive System Based on Linear Active Disturbance Rejection Controller

    NASA Astrophysics Data System (ADS)

    Liu, Liying; Zhang, Yongli; Yao, Qingmei

    It is difficult to establish an exact mathematical model for the induction motor and the robustness is poor of the vector control system using PI regulator. This paper adopts the linear active disturbance rejection controller (LADRC) to control inductor motor. LADRC doesn't need the exact mathematical model of motor and it can not only estimate but also compensate the general disturbance that includes the coupling items in model of motor and parameters perturbations by linear extended state observer (LESO), so the rotor flux and torque fully decouple. As a result, the performance is improved. To prove the above control scheme, the proposed control system has been simulated in MATLAB/SIMULINK, and the comparison was made with PID. Simulation results show that LADRC' has better performance and robustness than PID.

  19. RHPN2 Drives Mesenchymal Transformation in Malignant Glioma by Triggering RhoA Activation

    PubMed Central

    Danussi, Carla; Akavia, Uri David; Niola, Francesco; Jovic, Andreja; Lasorella, Anna; Pe’er, Dana; Iavarone, Antonio

    2013-01-01

    Summary Mesenchymal (MES) transformation is a hallmark of aggressive glioblastoma (GBM). Here we report the development of an unbiased method for computational integration of copy number variation, expression and mutation data from large datasets. Using this method we identified RHPN2 as a central genetic determinant of the MES phenotype of human GBM. Notably, amplification of the human RHPN2 gene on chromosome 19 correlates with a dramatic decrease in the survival of glioma patients. Ectopic expression of RHPN2 in neural stem cells and astrocytes triggered the expression of MES genes and promoted an invasive phenotype without impacting cell proliferation. Mechanistically, these effects were implemented through RHPN2-mediated activation of RhoA, a master regulator of cell migration and invasion. Our results define RHPN2 amplification as a central genetic determinant of a highly aggressive phenotype that directs the worst clinical outcomes in GBM patients. PMID:23774217

  20. Pseudomonas aeruginosa Induced Airway Epithelial Injury Drives Fibroblast Activation: A Mechanism in Chronic Lung Allograft Dysfunction.

    PubMed

    Borthwick, L A; Suwara, M I; Carnell, S C; Green, N J; Mahida, R; Dixon, D; Gillespie, C S; Cartwright, T N; Horabin, J; Walker, A; Olin, E; Rangar, M; Gardner, A; Mann, J; Corris, P A; Mann, D A; Fisher, A J

    2016-06-01

    Bacterial infections after lung transplantation cause airway epithelial injury and are associated with an increased risk of developing bronchiolitis obliterans syndrome. The damaged epithelium is a source of alarmins that activate the innate immune system, yet their ability to activate fibroblasts in the development of bronchiolitis obliterans syndrome has not been evaluated. Two epithelial alarmins were measured longitudinally in bronchoalveolar lavages from lung transplant recipients who developed bronchiolitis obliterans syndrome and were compared to stable controls. In addition, conditioned media from human airway epithelial cells infected with Pseudomonas aeruginosa was applied to lung fibroblasts and inflammatory responses were determined. Interleukin-1 alpha (IL-1α) was increased in bronchoalveolar lavage of lung transplant recipients growing P. aeruginosa (11.5 [5.4-21.8] vs. 2.8 [0.9-9.4] pg/mL, p < 0.01) and was significantly elevated within 3 months of developing bronchiolitis obliterans syndrome (8.3 [1.4-25.1] vs. 3.6 [0.6-17.1] pg/mL, p < 0.01), whereas high mobility group protein B1 remained unchanged. IL-1α positively correlated with elevated bronchoalveolar lavage IL-8 levels (r(2)  = 0.6095, p < 0.0001) and neutrophil percentage (r(2)  = 0.25, p = 0.01). Conditioned media from P. aeruginosa infected epithelial cells induced a potent pro-inflammatory phenotype in fibroblasts via an IL-1α/IL-1R-dependent signaling pathway. In conclusion, we propose that IL-1α may be a novel therapeutic target to limit Pseudomonas associated allograft injury after lung transplantation. PMID:26714197

  1. 6. UPPER NOTTINGHAM TAILING PILE LOOKING DOWN STREAM BED TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. UPPER NOTTINGHAM TAILING PILE LOOKING DOWN STREAM BED TO LOWER NOTTINGHAM. COLLAPSED BUILDINGS, 'B' AND 'C' AND TOP EDGE OF TAILING PILES ARE VISIBLE IN CENTRAL ARE OF PRINT. CAMERA POINTED SOUTHWEST. - Florida Mountain Mining Sites, Upper Nottingham Mine, West face of Florida Mountain, head of Jacobs Gulch, Silver City, Owyhee County, ID

  2. Navy-ship plastic waste recycled into marine pilings

    SciTech Connect

    March, F.A.

    1996-02-01

    Seaward International Inc., developed a new, composite, structurally reinforced, plastic-composite marine piling fabricated from 100 percent recycled plastic. A cooperative research program was begun in 1995 between the Navy and Seaward to develop a use for Navy ships waste plastic as a core in the construction of the marine piling.

  3. Packing bunkers and piles to maximize forage preservation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forage is a valuable commodity stored on dairy farms. Bunker and pile silos have increased in use due to increasing herd size. Losses in feed value in bunker and pile silos are frequently higher than they should be because producers are not packing them sufficiently to exclude oxygen during the stor...

  4. 30 CFR 77.214 - Refuse piles; general.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Refuse piles; general. 77.214 Section 77.214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... covered with clay or other inert material as the piles are constructed. (c) A fireproof barrier of clay...

  5. 30 CFR 77.214 - Refuse piles; general.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Refuse piles; general. 77.214 Section 77.214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... covered with clay or other inert material as the piles are constructed. (c) A fireproof barrier of clay...

  6. 30 CFR 77.214 - Refuse piles; general.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Refuse piles; general. 77.214 Section 77.214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... covered with clay or other inert material as the piles are constructed. (c) A fireproof barrier of clay...

  7. 30 CFR 77.214 - Refuse piles; general.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Refuse piles; general. 77.214 Section 77.214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... covered with clay or other inert material as the piles are constructed. (c) A fireproof barrier of clay...

  8. 30 CFR 77.214 - Refuse piles; general.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; general. 77.214 Section 77.214 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... covered with clay or other inert material as the piles are constructed. (c) A fireproof barrier of clay...

  9. Modeling the damming effect of pile foundations (Tomsk city)

    NASA Astrophysics Data System (ADS)

    Kuzevanov, K. I.; Pokrovsky, D. S.; Pokrovsky, V. D.; Kuzevanov, K. K.

    2016-03-01

    The authors have considered the impact of pile foundations on the structure of filtration flows in the conditions of urban development. Hydrodynamic simulation methods have shown that a groundwater level rise might occur due to the damming effect that can be created by pile fields in semipermeable rocks. This phenomenon can intensify anthropogenic waterlogging processes in urbanized territories.

  10. View south along subtle ridgeline across a pile of removed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View south along subtle ridgeline across a pile of removed gravestones to Doughty-Beck monument, another gravestone pile, and Mill Street houses. - Mount Zion Cemetery/ Female Union Band Cemetery, Bounded by 27th Street right-of-way N.W. (formerly Lyons Mill Road), Q Street N.W., & Mill Road N.W., Washington, District of Columbia, DC

  11. Multibody dynamics driving GNC and system design in tethered nets for active debris removal

    NASA Astrophysics Data System (ADS)

    Benvenuto, Riccardo; Lavagna, Michèle; Salvi, Samuele

    2016-07-01

    Debris removal in Earth orbits is an urgent issue to be faced for space exploitation durability. Among different techniques, tethered-nets present appealing benefits and some open points to fix. Former and latter are discussed in the paper, supported by the exploitation of a multibody dynamics tool. With respect to other proposed capture mechanisms, tethered-net solutions are characterised by a safer capturing distance, a passive angular momentum damping effect and the highest flexibility to unknown shape, material and attitude of the target to interface with. They also allow not considering the centre of gravity alignment with thrust axis as a constraint, as it is for any rigid link solution. Furthermore, the introduction of a closing thread around the net perimeter ensures safer and more reliable grasping and holding. In the paper, a six degrees of freedom multibody dynamics simulator is presented: it was developed at Politecnico di Milano - Department of Aerospace Science and Technologies - and it is able to describe the orbital and attitude dynamics of tethered-nets systems and end-bodies during different phases, with great flexibility in dealing with different topologies and configurations. Critical phases as impact and wrapping are analysed by simulation to address the tethered-stack controllability. It is shown how the role of contact modelling is fundamental to describe the coupled dynamics: it is demonstrated, as a major novel contribution, how friction between the net and a tumbling target allows reducing its angular motion, stabilizing the system and allowing safer towing operations. Moreover, the so-called tethered space tug is analysed: after capture, the two objects, one passive and one active, are connected by the tethered-net flexible link, the motion of the system being excited by the active spacecraft thrusters. The critical modes prevention during this phase, by means of a closed-loop control synthesis is shown. Finally, the connection between

  12. Reading Text While Driving

    PubMed Central

    Horrey, William J.; Hoffman, Joshua D.

    2015-01-01

    Objective In this study, we investigated how drivers adapt secondary-task initiation and time-sharing behavior when faced with fluctuating driving demands. Background Reading text while driving is particularly detrimental; however, in real-world driving, drivers actively decide when to perform the task. Method In a test track experiment, participants were free to decide when to read messages while driving along a straight road consisting of an area with increased driving demands (demand zone) followed by an area with low demands. A message was made available shortly before the vehicle entered the demand zone. We manipulated the type of driving demands (baseline, narrow lane, pace clock, combined), message format (no message, paragraph, parsed), and the distance from the demand zone when the message was available (near, far). Results In all conditions, drivers started reading messages (drivers’ first glance to the display) before entering or before leaving the demand zone but tended to wait longer when faced with increased driving demands. While reading messages, drivers looked more or less off road, depending on types of driving demands. Conclusions For task initiation, drivers avoid transitions from low to high demands; however, they are not discouraged when driving demands are already elevated. Drivers adjust time-sharing behavior according to driving demands while performing secondary tasks. Nonetheless, such adjustment may be less effective when total demands are high. Application This study helps us to understand a driver’s role as an active controller in the context of distracted driving and provides insights for developing distraction interventions. PMID:25850162

  13. Premature activation of the HIV RNase H drives the virus into suicide: a novel microbicide?

    PubMed

    Broecker, Felix; Andrae, Karsten; Moelling, Karin

    2012-11-01

    Sexual transmission of HIV is the major cause of spread of HIV in Africa and the Third World and is an unmet medical need. Recently, microbicides have attracted attention because they allow females to protect themselves and their offspring. We are exploiting one of the four retroviral enzymes, the ribonuclease H, RNase H, as a novel approach for a microbicide. It is the only enzyme of HIV not yet targeted by antiretroviral therapy. The enzyme is linked to the reverse transcriptase (RT) and hydrolyzes the RNA moiety of RNA-DNA hybrids. The RNase H is located inside virus particles and normally functions during viral replication inside cells. Here we show that activating the RNase H prematurely inside the virus particles destroys the viral genome and abrogates viral infectivity. The antiviral compound consists of a synthetic oligodeoxynucleotide (ODN), which creates an artificial RNA-DNA hybrid substrate for the RNase H inside the particle. The compound was analyzed in mouse models including humanized SCID mice and the vagina of mice. Infection was reduced up to 1000-fold or could be completely prevented. The compound is suitable as microbicide or to prevent mother-to-child transmission. PMID:22931114

  14. Activating Akt and the brain's resources to drive cellular survival and prevent inflammatory injury

    PubMed Central

    Chong, Z.Z.; Li, F.; Maiese, K.

    2008-01-01

    Summary Protein kinase B, also known as Akt, is a serine/threonine kinase and plays a critical role in the modulation of cell development, growth, and survival. Interestingly, Akt is ubiquitously expressed throughout the body, but its expression in the nervous system is substantially up-regulated during cellular stress, suggesting a more expansive role for Akt in the nervous system that may involve cellular protection. In this regard, a body of recent work has identified a robust capacity for Akt and its downstream substrates to foster both neuronal and vascular survival during apoptotic injury. Cell survival by Akt is driven by the modulation of both intrinsic cellular pathways that oversee genomic DNA integrity and extrinsic mechanisms that control inflammatory microglial activation. A series of distinct pathways are regulated by Akt that include the Forkhead family of transcription factors, GSK-3ß, ß-catenin, c-Jun, CREB, Bad, IKK, and p53. Culminating below these substrates of Akt are the control of caspase mediated pathways that promote genomic integrity as well as prevent inflammatory cell demise. With further levels of progress in defining the cellular role of Akt, the attractiveness of Akt as a vital and broad cytoprotectant for both neuronal and vascular cell populations should continue to escalate. PMID:15578447

  15. ZIC2-dependent OCT4 activation drives self-renewal of human liver cancer stem cells

    PubMed Central

    Zhu, Pingping; Wang, Yanying; He, Lei; Huang, Guanling; Du, Ying; Zhang, Geng; Yan, Xinlong; Xia, Pengyan; Ye, Buqing; Wang, Shuo; Hao, Lu; Wu, Jiayi; Fan, Zusen

    2015-01-01

    Liver cancer stem cells (CSCs) have been identified and shown to have self-renewal and differentiation properties; however, the biology of these hepatic CSCs remains largely unknown. Here, we analyzed transcriptome gene expression profiles of liver CSCs and non-CSCs from hepatocellular carcinoma (HCC) cells lines and found that the transcription factor (TF) ZIC2 is highly expressed in liver CSCs. ZIC2 was required for the self-renewal maintenance of liver CSCs, as ZIC2 depletion reduced sphere formation and xenograft tumor growth in mice. We determined that ZIC2 acts upstream of the TF OCT4 and that ZIC2 recruits the nuclear remodeling factor (NURF) complex to the OCT4 promoter, thereby initiating OCT4 activation. In HCC patients, expression levels of the NURF complex were consistent with clinical severity and prognosis. Moreover, ZIC2 and OCT4 levels positively correlated to the clinicopathological stages of HCC patients. Altogether, our results indicate that levels of ZIC2, OCT4, and the NURF complex can be detected and used for diagnosis and prognosis prediction of HCC patients. Moreover, these factors may be potential therapeutic targets for eradicating liver CSCs. PMID:26426078

  16. Posterior Parietal Cortex Drives Inferotemporal Activations During Three-Dimensional Object Vision

    PubMed Central

    Van Dromme, Ilse C.; Premereur, Elsie; Verhoef, Bram-Ernst; Vanduffel, Wim; Janssen, Peter

    2016-01-01

    The primate visual system consists of a ventral stream, specialized for object recognition, and a dorsal visual stream, which is crucial for spatial vision and actions. However, little is known about the interactions and information flow between these two streams. We investigated these interactions within the network processing three-dimensional (3D) object information, comprising both the dorsal and ventral stream. Reversible inactivation of the macaque caudal intraparietal area (CIP) during functional magnetic resonance imaging (fMRI) reduced fMRI activations in posterior parietal cortex in the dorsal stream and, surprisingly, also in the inferotemporal cortex (ITC) in the ventral visual stream. Moreover, CIP inactivation caused a perceptual deficit in a depth-structure categorization task. CIP-microstimulation during fMRI further suggests that CIP projects via posterior parietal areas to the ITC in the ventral stream. To our knowledge, these results provide the first causal evidence for the flow of visual 3D information from the dorsal stream to the ventral stream, and identify CIP as a key area for depth-structure processing. Thus, combining reversible inactivation and electrical microstimulation during fMRI provides a detailed view of the functional interactions between the two visual processing streams. PMID:27082854

  17. Salmonella Infection Drives Promiscuous B Cell Activation Followed by Extrafollicular Affinity Maturation.

    PubMed

    Di Niro, Roberto; Lee, Seung-Joo; Vander Heiden, Jason A; Elsner, Rebecca A; Trivedi, Nikita; Bannock, Jason M; Gupta, Namita T; Kleinstein, Steven H; Vigneault, Francois; Gilbert, Tamara J; Meffre, Eric; McSorley, Stephen J; Shlomchik, Mark J

    2015-07-21

    The B cell response to Salmonella typhimurium (STm) occurs massively at extrafollicular sites, without notable germinal centers (GCs). Little is known in terms of its specificity. To expand the knowledge of antigen targets, we screened plasmablast (PB)-derived monoclonal antibodies (mAbs) for Salmonella specificity, using ELISA, flow cytometry, and antigen microarray. Only a small fraction (0.5%-2%) of the response appeared to be Salmonella-specific. Yet, infection of mice with limited B cell receptor (BCR) repertoires impaired the response, suggesting that BCR specificity was important. We showed, using laser microdissection, that somatic hypermutation (SHM) occurred efficiently at extrafollicular sites leading to affinity maturation that in turn led to detectable STm Ag-binding. These results suggest a revised vision of how clonal selection and affinity maturation operate in response to Salmonella. Clonal selection initially is promiscuous, activating cells with virtually undetectable affinity, yet SHM and selection occur during the extrafollicular response yielding higher affinity, detectable antibodies. PMID:26187411

  18. Wheat amylase trypsin inhibitors drive intestinal inflammation via activation of toll-like receptor 4

    PubMed Central

    Junker, Yvonne; Zeissig, Sebastian; Kim, Seong-Jun; Barisani, Donatella; Wieser, Herbert; Leffler, Daniel A.; Zevallos, Victor; Libermann, Towia A.; Dillon, Simon; Freitag, Tobias L.; Kelly, Ciaran P.

    2012-01-01

    Ingestion of wheat, barley, or rye triggers small intestinal inflammation in patients with celiac disease. Specifically, the storage proteins of these cereals (gluten) elicit an adaptive Th1-mediated immune response in individuals carrying HLA-DQ2 or HLA-DQ8 as major genetic predisposition. This well-defined role of adaptive immunity contrasts with an ill-defined component of innate immunity in celiac disease. We identify the α-amylase/trypsin inhibitors (ATIs) CM3 and 0.19, pest resistance molecules in wheat, as strong activators of innate immune responses in monocytes, macrophages, and dendritic cells. ATIs engage the TLR4–MD2–CD14 complex and lead to up-regulation of maturation markers and elicit release of proinflammatory cytokines in cells from celiac and nonceliac patients and in celiac patients’ biopsies. Mice deficient in TLR4 or TLR4 signaling are protected from intestinal and systemic immune responses upon oral challenge with ATIs. These findings define cereal ATIs as novel contributors to celiac disease. Moreover, ATIs may fuel inflammation and immune reactions in other intestinal and nonintestinal immune disorders. PMID:23209313

  19. Some problems of sensitivity analysis of axially loaded piles

    SciTech Connect

    Budkowska, B.B.; Szymczak, C.

    1994-12-31

    The first variations of an axial displacement and an axial force at a specified cross-section of an axially loaded pile due to the changes of the design variables are derived. The parameters describing the pile material and the soil behavior as well as the pile cross-section dimensions are assumed to be the design variables. A simple one-dimensional idealization of the pile in conjunction with a nonlinear Winkler-type model of the soil is adopted. The considerations based on the virtual work theorems are valid for both linear and nonlinear ranges of the pile material and the soil behavior. Some presented numerical examples allow one to investigate the accuracy of approximation of changes of internal forces and displacements due to the increments of the design variables by means of their first order variations.

  20. Method of extracting coal from a coal refuse pile

    DOEpatents

    Yavorsky, Paul M.

    1991-01-01

    A method of extracting coal from a coal refuse pile comprises soaking the coal refuse pile with an aqueous alkali solution and distributing an oxygen-containing gas throughout the coal refuse pile for a time period sufficient to effect oxidation of coal contained in the coal refuse pile. The method further comprises leaching the coal refuse pile with an aqueous alkali solution to solubilize and extract the oxidized coal as alkali salts of humic acids and collecting the resulting solution containing the alkali salts of humic acids. Calcium hydroxide may be added to the solution of alkali salts of humic acid to form precipitated humates useable as a low-ash, low-sulfur solid fuel.

  1. Distributed fibre optic strain measurements on a driven pile

    NASA Astrophysics Data System (ADS)

    Woschitz, Helmut; Monsberger, Christoph; Hayden, Martin

    2016-05-01

    In civil engineering pile systems are used in unstable areas as a foundation of buildings or other structures. Among other parameters, the load capacity of the piles depends on their length. A better understanding of the mechanism of load-transfer to the soil would allow selective optimisation of the system. Thereby, the strain variations along the loaded pile are of major interest. In this paper, we report about a field trial using an optical backscatter reflectometer for distributed fibre-optic strain measurements along a driven pile. The most significant results gathered in a field trial with artificial pile loadings are presented. Calibration results show the performance of the fibre-optic system with variations in the strain-optic coefficient.

  2. Optimal Design of Sheet Pile Wall Embedded in Clay

    NASA Astrophysics Data System (ADS)

    Das, Manas Ranjan; Das, Sarat Kumar

    2015-09-01

    Sheet pile wall is a type of flexible earth retaining structure used in waterfront offshore structures, river protection work and temporary supports in foundations and excavations. Economy is an essential part of a good engineering design and needs to be considered explicitly in obtaining an optimum section. By considering appropriate embedment depth and sheet pile section it may be possible to achieve better economy. This paper describes optimum design of both cantilever and anchored sheet pile wall penetrating clay using a simple optimization tool Microsoft Excel ® Solver. The detail methodology and its application with examples are presented for cantilever and anchored sheet piles. The effects of soil properties, depth of penetration and variation of ground water table on the optimum design are also discussed. Such a study will help professional while designing the sheet pile wall penetrating clay.

  3. The Analysis of Soil Resistance During Screw Displacement Pile Installation

    NASA Astrophysics Data System (ADS)

    Krasinski, Adam

    2015-02-01

    The application of screw displacement piles (SDP) is still increasing due to their high efficiency and many advantages. However, one technological problem is a serious disadvantage of those piles. It relates to the generation of very high soil resistance during screw auger penetration, especially when piles are installed in non-cohesive soils. In many situations this problem causes difficulties in creating piles of designed length and diameter. It is necessary to find a proper method for prediction of soil resistance during screw pile installation. The analysis of screw resistances based on model and field tests is presented in the paper. The investigations were carried out as part of research project, financed by the Polish Ministry of Science and Higher Education. As a result of tests and analyses the empirical method for prediction of rotation resistance (torque) during screw auger penetration in non-cohesive subsoil based on CPT is proposed.

  4. SHAKING TABLE TESTS ON SEISMIC DEFORMATION OF PILE SUPPORTED PIER

    NASA Astrophysics Data System (ADS)

    Fujita, Daiki; Kohama, Eiji; Takenobu, Masahiro; Yoshida, Makoto; Kiku, Hiroyoshi

    The seismic deformation characeteristics of a pile supported pier was examined with the shake table test, especially focusing on the pier after its deformation during earthquakes. The model based on the similitude of the fully-plastic moment in piles was prepared to confirm the deformation and stress characteristic after reaching the fully-plastic moment. Moreover, assuming transportation of emergency supplies and occurrence of after shock in the post-disaster period, the pile supported pier was loaded with weight after reaching fully-plastic moment and excited with the shaking table. As the result, it is identified that the displacement of the pile supported pier is comparatively small if bending strength of piles does not decrease after reaching fully-plastic moment due to nonoccourrence of local backling or strain hardening.

  5. Vertical vibration of a pile in transversely isotropic multilayered soils

    NASA Astrophysics Data System (ADS)

    Ai, Zhi Yong; Liu, Chun Lin

    2015-11-01

    A new method for the dynamic response of a vertically loaded single pile embedded in transversely isotropic multilayered soils is proposed in this paper. The dynamic response of the pile is governed by the one-dimensional (1D) vibration theory, and that of transversely isotropic multilayered soils is achieved by using an analytical layer-element method. Then, with the aid of the displacement compatibility and the contact forces equilibrium along the pile-soil contact surface, the dynamic pile-soil interaction problem is solved efficiently. The presented solution method is proved to be correct and efficient by comparing the obtained results with other existing solutions. Selected numerical results are presented to study the influence of mass density ratio, length-radius ratio, frequency of excitation, soil anisotropy and hard soil stratum on the pile vertical impedance.

  6. Signal transducer and activator of transcription 3 promotes angiogenesis and drives malignant progression in glioma.

    PubMed

    Doucette, Tiffany A; Kong, Ling-Yuan; Yang, Yuhui; Ferguson, Sherise D; Yang, Jinbo; Wei, Jun; Qiao, Wei; Fuller, Gregory N; Bhat, Krishna P; Aldape, Kenneth; Priebe, Waldemar; Bögler, Oliver; Heimberger, Amy B; Rao, Ganesh

    2012-09-01

    Signal transducer and activator of transcription (STAT) 3 has been described as a "master regulator" of signaling pathways involved in the transition from low-grade glioma (LGG) to high-grade glioma (HGG). Although STAT3 is overexpressed in HGGs, it remains unclear whether its overexpression is sufficient to induce or promote the malignant progression of glioma. To characterize the effect of STAT3 expression on tumor progression in vivo, we expressed the STAT3 gene in glioneuronal progenitor cells in mice. STAT3 was expressed alone or concurrently with platelet-derived growth factor B (PDGFB), a well-described initiator of LGG. STAT3 alone was insufficient to induce tumor formation; however, coexpression of STAT3 with PDGFB in mice resulted in a significantly higher incidence of HGGs than PDGFB alone. The median symptomatic tumor latency in mice coexpressing STAT3 and PDGFB was significantly shorter, and mice that developed symptomatic tumors demonstrated significantly higher expression of phosphorylated STAT3 intratumorally. In HGGs, expression of STAT3 was associated with suppression of apoptosis and an increase in tumor cell proliferation. HGGs induced by STAT3 and PDGFB also displayed frequent foci of necrosis and microvascular proliferation. The expression of CD31 (a marker of endothelial proliferation) was significantly higher in tumors induced by coexpression of STAT3 and PDGFB. When mice injected with PDGFB and STAT3 were treated with a STAT3 inhibitor, median survival increased and the incidence of HGG and CD31 expression decreased significantly. These results demonstrate that STAT3 promotes the malignant progression of glioma. Inhibiting STAT3 expression mitigates tumor progression and improves survival, validating it as a therapeutic target. PMID:22753228

  7. Signal transducer and activator of transcription 3 promotes angiogenesis and drives malignant progression in glioma

    PubMed Central

    Doucette, Tiffany A.; Kong, Ling-Yuan; Yang, Yuhui; Ferguson, Sherise D.; Yang, Jinbo; Wei, Jun; Qiao, Wei; Fuller, Gregory N.; Bhat, Krishna P.; Aldape, Kenneth; Priebe, Waldemar; Bögler, Oliver; Heimberger, Amy B.; Rao, Ganesh

    2012-01-01

    Signal transducer and activator of transcription (STAT) 3 has been described as a “master regulator” of signaling pathways involved in the transition from low-grade glioma (LGG) to high-grade glioma (HGG). Although STAT3 is overexpressed in HGGs, it remains unclear whether its overexpression is sufficient to induce or promote the malignant progression of glioma. To characterize the effect of STAT3 expression on tumor progression in vivo, we expressed the STAT3 gene in glioneuronal progenitor cells in mice. STAT3 was expressed alone or concurrently with platelet-derived growth factor B (PDGFB), a well-described initiator of LGG. STAT3 alone was insufficient to induce tumor formation; however, coexpression of STAT3 with PDGFB in mice resulted in a significantly higher incidence of HGGs than PDGFB alone. The median symptomatic tumor latency in mice coexpressing STAT3 and PDGFB was significantly shorter, and mice that developed symptomatic tumors demonstrated significantly higher expression of phosphorylated STAT3 intratumorally. In HGGs, expression of STAT3 was associated with suppression of apoptosis and an increase in tumor cell proliferation. HGGs induced by STAT3 and PDGFB also displayed frequent foci of necrosis and microvascular proliferation. The expression of CD31 (a marker of endothelial proliferation) was significantly higher in tumors induced by coexpression of STAT3 and PDGFB. When mice injected with PDGFB and STAT3 were treated with a STAT3 inhibitor, median survival increased and the incidence of HGG and CD31 expression decreased significantly. These results demonstrate that STAT3 promotes the malignant progression of glioma. Inhibiting STAT3 expression mitigates tumor progression and improves survival, validating it as a therapeutic target. PMID:22753228

  8. An estrogen-responsive module in the ventromedial hypothalamus selectively drives sex-specific activity in females.

    PubMed

    Correa, Stephanie M; Newstrom, David W; Warne, James P; Flandin, Pierre; Cheung, Clement C; Lin-Moore, Alexander T; Pierce, Andrew A; Xu, Allison W; Rubenstein, John L; Ingraham, Holly A

    2015-01-01

    Estrogen-receptor alpha (ERα) neurons in the ventrolateral region of the ventromedial hypothalamus (VMHVL) control an array of sex-specific responses to maximize reproductive success. In females, these VMHVL neurons are believed to coordinate metabolism and reproduction. However, it remains unknown whether specific neuronal populations control distinct components of this physiological repertoire. Here, we identify a subset of ERα VMHVL neurons that promotes hormone-dependent female locomotion. Activating Nkx2-1-expressing VMHVL neurons via pharmacogenetics elicits a female-specific burst of spontaneous movement, which requires ERα and Tac1 signaling. Disrupting the development of Nkx2-1(+) VMHVL neurons results in female-specific obesity, inactivity, and loss of VMHVL neurons coexpressing ERα and Tac1. Unexpectedly, two responses controlled by ERα(+) neurons, fertility and brown adipose tissue thermogenesis, are unaffected. We conclude that a dedicated subset of VMHVL neurons marked by ERα, NKX2-1, and Tac1 regulates estrogen-dependent fluctuations in physical activity and constitutes one of several neuroendocrine modules that drive sex-specific responses. PMID:25543145

  9. Antiosteoporotic Activity of Dioscorea alata L. cv. Phyto through Driving Mesenchymal Stem Cells Differentiation for Bone Formation

    PubMed Central

    Peng, Kang-Yung; Horng, Lin-Yea; Sung, Hui-Ching; Huang, Hui-Chuan; Wu, Rong-Tsun

    2011-01-01

    The aim of this study was to evaluate the effect of an ethanol extract of the rhizomes of Dioscorea alata L. cv. Phyto, Dispo85E, on bone formation and to investigate the mechanisms involved. Our results showed that Dispo85E increased the activity of alkaline phosphatase (ALP) and bone nodule formation in primary bone marrow cultures. In addition, Dispo85E stimulated pluripotent C3H10T1/2 stem cells to differentiate into osteoblasts rather than adipocytes. Our in vivo data indicated that Dispo85E promotes osteoblastogenesis by increasing ALP activity and bone nodule formation in both intact and ovariectomized (OVX) mice. Microcomputed tomography (μCT) analysis also showed that Dispo85E ameliorates the deterioration of trabecular bone mineral density (tBMD), trabecular bone volume/total volume (BV/TV), and trabecular bone number (Tb.N) in OVX mice. Our results suggested that Dispo85E is a botanical drug with a novel mechanism that drives the lineage-specific differentiation of bone marrow stromal cells and is a candidate drug for osteoporosis therapy. PMID:21760825

  10. An Estrogen-Responsive Module in the Ventromedial Hypothalamus Selectively Drives Sex-Specific Activity in Females

    PubMed Central

    Correa, Stephanie M.; Newstrom, David W.; Warne, James P.; Flandin, Pierre; Cheung, Clement C.; Lin-Moore, Alexander T.; Pierce, Andrew A.; Xu, Allison W.; Rubenstein, John L.; Ingraham, Holly A.

    2015-01-01

    Estrogen-receptor alpha (ERα) neurons in the ventrolateral region of the ventromedial hypothalamus (VMHVL) control an array of sex-specific responses to maximize reproductive success. In females, these VMHVL neurons are believed to coordinate metabolism and reproduction. However, it remains unknown whether specific neuronal populations control distinct components of this physiological repertoire. Here, we identify a subset of ERα VMHVL neurons that promotes hormone-dependent female locomotion. Activating Nkx2-1-expressing VMHVL neurons via pharmacogenetics elicits a female-specific burst of spontaneous movement, which requires ERα and Tac1 signaling. Disrupting development of Nkx2-1+ VMHVL neurons results in female-specific obesity, inactivity, and loss of VMHVL neurons co-expressing ERα and Tac1. Unexpectedly, two responses controlled by ERα neurons, fertility and brown adipose tissue thermogenesis, are unaffected. We conclude that a dedicated subset of VMHVL neurons marked by ERα, NKX2-1, and Tac1 regulates estrogen-dependent fluctuations in physical activity and constitutes one of several neuroendocrine modules that drive sex-specific responses. PMID:25543145

  11. Inefficient Driving of Bulk Turbulence By Active Galactic Nuclei in a Hydrodynamic Model of the Intracluster Medium

    NASA Astrophysics Data System (ADS)

    Reynolds, Christopher S.; Balbus, Steven A.; Schekochihin, Alexander A.

    2015-12-01

    Central jetted active galactic nuclei (AGNs) appear to heat the core regions of the intracluster medium (ICM) in cooling-core galaxy clusters and groups, thereby preventing a cooling catastrophe. However, the physical mechanism(s) by which the directed flow of kinetic energy is thermalized throughout the ICM core remains unclear. We examine one widely discussed mechanism whereby the AGN induces subsonic turbulence in the ambient medium, the dissipation of which provides the ICM heat source. Through controlled inviscid three-dimensional hydrodynamic simulations, we verify that explosive AGN-like events can launch gravity waves (g-modes) into the ambient ICM, which in turn decays to volume-filling turbulence. In our model, however, this process is found to be inefficient, with less than 1% of the energy injected by the AGN activity actually ending up in the turbulence of the ambient ICM. This efficiency is an order of magnitude or more too small to explain the observations of AGN-feedback in galaxy clusters and groups with short central cooling times. Atmospheres in which the g-modes are strongly trapped/confined have an even lower efficiency since, in these models, the excitation of turbulence relies on the g-modes’ ability to escape from the center of the cluster into the bulk ICM. Our results suggest that, if AGN-induced turbulence is indeed the mechanism by which the AGN heats the ICM core, its driving may rely on physics beyond that captured in our ideal hydrodynamic model.

  12. Bruchpilot and Synaptotagmin collaborate to drive rapid glutamate release and active zone differentiation.

    PubMed

    Paul, Mila M; Pauli, Martin; Ehmann, Nadine; Hallermann, Stefan; Sauer, Markus; Kittel, Robert J; Heckmann, Manfred

    2015-01-01

    The active zone (AZ) protein Bruchpilot (Brp) is essential for rapid glutamate release at Drosophila melanogaster neuromuscular junctions (NMJs). Quantal time course and measurements of action potential-waveform suggest that presynaptic fusion mechanisms are altered in brp null mutants (brp(69) ). This could account for their increased evoked excitatory postsynaptic current (EPSC) delay and rise time (by about 1 ms). To test the mechanism of release protraction at brp(69) AZs, we performed knock-down of Synaptotagmin-1 (Syt) via RNAi (syt(KD) ) in wildtype (wt), brp(69) and rab3 null mutants (rab3(rup) ), where Brp is concentrated at a small number of AZs. At wt and rab3(rup) synapses, syt(KD) lowered EPSC amplitude while increasing rise time and delay, consistent with the role of Syt as a release sensor. In contrast, syt(KD) did not alter EPSC amplitude at brp(69) synapses, but shortened delay and rise time. In fact, following syt(KD) , these kinetic properties were strikingly similar in wt and brp(69) , which supports the notion that Syt protracts release at brp(69) synapses. To gain insight into this surprising role of Syt at brp(69) AZs, we analyzed the structural and functional differentiation of synaptic boutons at the NMJ. At 'tonic' type Ib motor neurons, distal boutons contain more AZs, more Brp proteins per AZ and show elevated and accelerated glutamate release compared to proximal boutons. The functional differentiation between proximal and distal boutons is Brp-dependent and reduced after syt(KD) . Notably, syt(KD) boutons are smaller, contain fewer Brp positive AZs and these are of similar number in proximal and distal boutons. In addition, super-resolution imaging via dSTORM revealed that syt(KD) increases the number and alters the spatial distribution of Brp molecules at AZs, while the gradient of Brp proteins per AZ is diminished. In summary, these data demonstrate that normal structural and functional differentiation of Drosophila AZs requires

  13. Environmentally Friendly Solution to Ground Hazards in Design of Bridges in Earthquake Prone Areas Using Timber Piles

    NASA Astrophysics Data System (ADS)

    Sadeghi, H.

    2015-12-01

    Bridges are major elements of infrastructure in all societies. Their safety and continued serviceability guaranties the transportation and emergency access in urban and rural areas. However, these important structures are subject to earthquake induced damages in structure and foundations. The basic approach to the proper support of foundations are a) distribution of imposed loads to foundation in a way they can resist those loads without excessive settlement and failure; b) modification of foundation ground with various available methods; and c) combination of "a" and "b". The engineers has to face the task of designing the foundations meeting all safely and serviceability criteria but sometimes when there are numerous environmental and financial constrains, the use of some traditional methods become inevitable. This paper explains the application of timber piles to improve ground resistance to liquefaction and to secure the abutments of short to medium length bridges in an earthquake/liquefaction prone area in Bohol Island, Philippines. The limitations of using the common ground improvement methods (i.e., injection, dynamic compaction) because of either environmental or financial concerns along with the abundance of timber in the area made the engineers to use a network of timber piles behind the backwalls of the bridge abutments. The suggested timber pile network is simulated by numerical methods and its safety is examined. The results show that the compaction caused by driving of the piles and bearing capacity provided by timbers reduce the settlement and lateral movements due to service and earthquake induced loads.

  14. Threat from Rubble-Pile Asteroids

    NASA Astrophysics Data System (ADS)

    Schultz, P. H.

    2015-12-01

    While chondrites are the most common meteoroids to enter our atmosphere, they represent a small fraction of recovered falls. Most stony meteorites disrupt during entry, consumed by ablation or lost by weathering; in contrast, small iron meteorites (<10 m) disrupt and disperse to create strewnfields due to interacting atmospheric bow shocks [e.g., Passey and Melosh, 1980]. The Carancas impact crater in 2007, however, challenged our understanding [Tancredi et al., 2008]: (a) first eyewitness of a crater formed by a stony meteorite; (b) undetected thermal entry at altitude; (c) no accessory meteorite falls; (d) "explosion" (not low-speed compression) crater; (e) infrasound/seismic data indicating a high-speed entry/collision; and (f) petrologic evidence for shock deformation/melting in breccias indicative of speeds >4 km/s. Although a monolithic chondrite (~ 10 m across) might allow surviving entry, most objects of this size contain multiple flaws, ensuring atmospheric disruption. Hence, an alternative "needle model" was proposed wherein a small rubble-pile object gradually re-shaped itself during entry [Schultz, 2008], a process that minimizes drag, thermal signatures of entry, and catastrophic disruption. First proposed to account for smaller than expected craters on Venus [Schultz, 1992], such a process resembles subsequent Shoemaker-Levy entry models [Boslough and Crawford, 1997] that predicted much deeper entry than standard models. Laboratory experiments at the NASA Ames Vertical Gun Range simulated this process by breaking-up hypervelocity projectiles into a cloud of debris and tracking its path at near-full atmospheric pressure. The resulting cloud of fragments exhibited less deceleration than a solid sphere at the same speed. Moreover, shadowgraphs revealed constituent fragments "surfing" the pressure jump within the mach cone/column. Previous models proposed that crater-forming impacts must be >50-100 m in diameter in order to survive entry [Bland and

  15. Small asteroids - rubble piles or boulders?

    NASA Astrophysics Data System (ADS)

    Harris, Alan W.

    2013-10-01

    The asteroid rotation spin barrier at ~2.2 h period among asteroids 10 km > D > 200 m doesn’t prove all such asteroids are rubble piles, and the faster rotations among smaller asteroids doesn’t require monolithic strength, either. Only a very modest strength, perhaps no more than van der Waals force, might suffice to hold regolith together on a small super-fast rotator (Sanchez & Scheeres, 2013, arXif:1306.1622v1). The problem is that for a constant or only slowly varying strength with respect to diameter, the spin barrier becomes proportional to 1/D below the size where material strength is dominant, or perhaps a bit steeper if strength increases with decreasing D. What we observe in the distribution of asteroid spins versus diameter is that below D ~ 200 m, the spin barrier goes up at least ~D-3.5, if not abruptly. Models with constant or slowly varying strength fail to fit this observation, and the abrupt transition cannot be an observational selection effect: the void in the phase space of rotations would be among the easiest rotations to observe, e.g. the one conspicuous exception, 2001 OE84 (D ~ 0.7 km, P = 0.5 h) was easily and unambiguously measured (Pravec, et al. 2002, Proc. ACM 2002, ESA SP-500, 743-745). This abrupt transition is most easily explained as a real transition in material properties of asteroids in the size range ~200 m diameter, from “rubble pile” to “boulder”, although neither term may be fully descriptive of the actual structure. Two other lines of evidence suggest that this transition in properties is real: the dip in the size-frequency distribution of NEAs is maximum at ~150 m, suggesting that a transition to stronger material structure occurs about there, and we observe, e.g., Tunguska and the recent Chelyabinsk bolide, that bodies in the tens of meters size range entering the atmosphere behave more like solid rocks than rock piles (Boslough & Crawford 2008, Int. J. Imp. Eng. 35, 1441-1448). I encourage those doing computer

  16. Formation of pebble-pile planetesimals

    NASA Astrophysics Data System (ADS)

    Wahlberg Jansson, Karl; Johansen, Anders

    2014-10-01

    Asteroids and Kuiper belt objects are remnant planetesimals from the epoch of planet formation. The first stage of planet formation is the accumulation of dust and ice grains into mm- and cm-sized pebbles. These pebbles can clump together through the streaming instability and form gravitationally bound pebble clouds. Pebbles inside such a cloud will undergo mutual collisions, dissipating energy into heat. As the cloud loses energy, it gradually contracts towards solid density. We model this process and investigate two important properties of the collapse: (i) the collapse timescale and (ii) the temporal evolution of the pebble size distribution. Our numerical model of the pebble cloud is zero-dimensional and treats collisions with a statistical method. We find that planetesimals with radii larger than ~100 km collapse on the free-fall timescale of ~25 years. Lower-mass clouds have longer pebble collision timescales and collapse much more slowly, with collapse times of a few hundred years for 10 km scale planetesimals and a few thousand years for 1 km scale planetesimals. The mass of the pebble cloud also determines the interior structure of the resulting planetesimal. The pebble collision speeds in low-mass clouds are below the threshold for fragmentation, forming pebble-pile planetesimals consisting of the primordial pebbles from the protoplanetary disk. Planetesimals above 100 km in radius, on the other hand, consist of mixtures of dust (pebble fragments) and pebbles which have undergone substantial collisions with dust and other pebbles. The Rosetta mission to the comet 67P/Churyumov-Gerasimenko and the New Horizons mission to Pluto will provide valuable information about the structure of planetesimals in the solar system. Our model predicts that 67P is a pebble-pile planetesimal consisting of primordial pebbles from the solar nebula, while the pebbles in the cloud which contracted to form Pluto must have been ground down substantially during the collapse.

  17. P2X7R activation drives distinct IL-1 responses in dendritic cells compared to macrophages

    PubMed Central

    Englezou, Pavlos C.; Rothwell, Simon W.; Ainscough, Joseph S.; Brough, David; Landsiedel, Robert; Verkhratsky, Alexei; Kimber, Ian; Dearman, Rebecca J.

    2015-01-01

    The P2X7R is a functionally distinct member of the P2X family of non-selective cation channels associated with rapid activation of the inflammasome complex and signalling interleukin (IL)-1β release in macrophages. The main focus of this investigation was to compare P2X7R-driven IL-1 production by primary murine bone marrow derived dendritic cells (BMDC) and macrophages (BMM). P2X7R expression in murine BMDC and BMM at both transcriptional (P2X7A variant) and protein levels was demonstrated. Priming with lipopolysaccharide (LPS) and receptor activation with adenosine triphosphate (ATP) resulted in markedly enhanced IL-1 (α and β) secretion in BMDC compared with BMM. In both cell types IL-1 production was profoundly inhibited with a P2X7R-specific inhibitor (A-740003) demonstrating that this release is predominantly a P2X7R-dependent process. These data also suggest that P2X7R and caspase-1 activation drive IL-1α release from BMDC. Both cell types expressed constitutively the gain-of-function P2X7K as well as the full P2X7A variant at equivalent levels. LPS priming reduced significantly levels of P2X7A but not P2X7K transcripts in both BMDC and BMM. P2X7R-induced pore formation, assessed by YO-PRO-1 dye uptake, was greater in BMDC, and these cells were protected from cell death. These data demonstrate that DC and macrophages display distinct patterns of cytokine regulation, particularly with respect to IL-1, as a consequence of cell-type specific differences in the physicochemical properties of the P2X7R. Understanding the cell-specific regulation of these cytokines is essential for manipulating such responses in health and disease. PMID:26068648

  18. ß1 Integrin Binding Phosphorylates Ezrin at T567 to Activate a Lipid Raft Signalsome Driving Invadopodia Activity and Invasion

    PubMed Central

    Antelmi, Ester; Cardone, Rosa A.; Greco, Maria R.; Rubino, Rosa; Di Sole, Francesca; Martino, Nicola A.; Casavola, Valeria; Carcangiu, MariaLuisa; Moro, Loredana; Reshkin, Stephan J.

    2013-01-01

    Extracellular matrix (ECM) degradation is a critical process in tumor cell invasion and requires matrix degrading protrusions called invadopodia. The Na+/H+ exchanger (NHE1) has recently been shown to be fundamental in the regulation of invadopodia actin cytoskeleton dynamics and activity. However, the structural link between the invadopodia cytoskeleton and NHE1 is still unknown. A candidate could be ezrin, a linker between the NHE1 and the actin cytoskeleton known to play a pivotal role in invasion and metastasis. However, the mechanistic basis for its role remains unknown. Here, we demonstrate that ezrin phosphorylated at T567 is highly overexpressed in the membrane of human breast tumors and positively associated with invasive growth and HER2 overexpression. Further, in the metastatic cell line, MDA-MB-231, p-ezrin was almost exclusively expressed in invadopodia lipid rafts where it co-localized in a functional complex with NHE1, EGFR, ß1-integrin and phosphorylated-NHERF1. Manipulation by mutation of ezrins T567 phosphorylation state and/or PIP2 binding capacity or of NHE1s binding to ezrin or PIP2 demonstrated that p-ezrin expression and binding to PIP2 are required for invadopodia-mediated ECM degradation and invasion and identified NHE1 as the membrane protein that p-ezrin regulates to induce invadopodia formation and activity. PMID:24086451

  19. Distracted Driving

    MedlinePlus

    ... combines all three types of distraction. 3 How big is the problem? Deaths In 2013, 3,154 ... European countries. More A CDC study analyzed 2011 data on distracted driving, including talking on a cell ...

  20. Distracted driving

    MedlinePlus

    ... stay safe with a cell phone in the car. ... for Disease Control and Prevention Injury Prevention & Control. Motor Vehicle Safety. www.cdc.gov/motorvehiclesafety/distracted_driving . Accessed May ...

  1. Driving Safely

    MedlinePlus

    ... drivers’ flexibility and coordination, and reduced driving errors. S l Hand grip strengthening to help you hold on to the steering wheel l Shoulder and upper arm flexibility exercises to make ...

  2. Platelet activating factor-induced ceramide micro-domains drive endothelial NOS activation and contribute to barrier dysfunction.

    PubMed

    Predescu, Sanda; Knezevic, Ivana; Bardita, Cristina; Neamu, Radu Florin; Brovcovych, Viktor; Predescu, Dan

    2013-01-01

    The spatial and functional relationship between platelet activating factor-receptor (PAF-R) and nitric oxide synthase (eNOS) in the lateral plane of the endothelial plasma membrane is poorly characterized. In this study, we used intact mouse pulmonary endothelial cells (ECs) as well as endothelial plasma membrane patches and subcellular fractions to define a new microdomain of plasmalemma proper where the two proteins colocalize and to demonstrate how PAF-mediated nitric oxide (NO) production fine-tunes ECs function as gatekeepers of vascular permeability. Using fluorescence microscopy and immunogold labeling electron microscopy (EM) on membrane patches we demonstrate that PAF-R is organized as clusters and colocalizes with a subcellular pool of eNOS, outside recognizable vesicular profiles. Moreover, PAF-induced acid sphingomyelinase activation generates a ceramide-based microdomain on the external leaflet of plasma membrane, inside of which a signalosome containing eNOS shapes PAF-stimulated NO production. Real-time measurements of NO after PAF-R ligation indicated a rapid (5 to 15 min) increase in NO production followed by a > 45 min period of reduction to basal levels. Moreover, at the level of this new microdomain, PAF induces a dynamic phosphorylation/dephosphorylation of Ser, Thr and Tyr residues of eNOS that correlates with NO production. Altogether, our findings establish the existence of a functional partnership PAF-R/eNOS on EC plasma membrane, at the level of PAF-induced ceramide plasma membrane microdomains, outside recognized vesicular profiles. PMID:24086643

  3. Platelet Activating Factor-Induced Ceramide Micro-Domains Drive Endothelial NOS Activation and Contribute to Barrier Dysfunction

    PubMed Central

    Predescu, Sanda; Knezevic, Ivana; Bardita, Cristina; Neamu, Radu Florin; Brovcovych, Viktor; Predescu, Dan

    2013-01-01

    The spatial and functional relationship between platelet activating factor-receptor (PAF-R) and nitric oxide synthase (eNOS) in the lateral plane of the endothelial plasma membrane is poorly characterized. In this study, we used intact mouse pulmonary endothelial cells (ECs) as well as endothelial plasma membrane patches and subcellular fractions to define a new microdomain of plasmalemma proper where the two proteins colocalize and to demonstrate how PAF-mediated nitric oxide (NO) production fine-tunes ECs function as gatekeepers of vascular permeability. Using fluorescence microscopy and immunogold labeling electron microscopy (EM) on membrane patches we demonstrate that PAF-R is organized as clusters and colocalizes with a subcellular pool of eNOS, outside recognizable vesicular profiles. Moreover, PAF-induced acid sphingomyelinase activation generates a ceramide-based microdomain on the external leaflet of plasma membrane, inside of which a signalosome containing eNOS shapes PAF-stimulated NO production. Real-time measurements of NO after PAF-R ligation indicated a rapid (5 to 15 min) increase in NO production followed by a > 45 min period of reduction to basal levels. Moreover, at the level of this new microdomain, PAF induces a dynamic phosphorylation/dephosphorylation of Ser, Thr and Tyr residues of eNOS that correlates with NO production. Altogether, our findings establish the existence of a functional partnership PAF-R/eNOS on EC plasma membrane, at the level of PAF-induced ceramide plasma membrane microdomains, outside recognized vesicular profiles. PMID:24086643

  4. Load tests on tubular piles in Coralline Strata

    SciTech Connect

    Gilchrist, J.M.

    1985-05-01

    At a coral reef site on the Red Sea coast of Saudi Arabia, load tests were performed on 1,422 mm diam tubular steel piles to verify pile design compression and tension capacities predicted by calculations. Although two tests were planned at separate site locations, five were performed (two on test pile A, and three on test pile B) due to the test results disproving some of the calculation assumptions. Test pile A was installed open-ended and the test results concluded: For a coring pile, the measured compression capacitites had reasonable agreement with those calculated (calculated overestimates = 5.2% and 16.3%); and the design assumption that a soil plug would form was disproved. Test pile B was installed with a structural plug fitted to the leading end and the test results concluded that the measured skin friction at 11 m penetration = zero; and the unit end bearing capacity assumed in the calculations was considerably larger than that measured in the tests at 11 m and 30 m penetration (calculated overestimates = 181% and 164%).

  5. Tumor-induced solid stress activates β-catenin signaling to drive malignant behavior in normal, tumor-adjacent cells

    PubMed Central

    Ou, Guanqing; Weaver, Valerie Marie

    2016-01-01

    Recent work by Fernández-Sánchez and coworkers examining the impact of applied pressure on the malignant phenotype of murine colon tissue in vivo revealed that mechanical perturbations can drive malignant behavior in genetically normal cells. Their findings build upon an existing understanding of how the mechanical cues experienced by cells within a tissue become progressively modified as the tissue transforms. Using magnetically stimulated ultra-magnetic liposomes to mimic tumor growth -induced solid stress, Fernández-Sánchez and coworkers were able to stimulate β-catenin to promote the cancerous behavior of both a normal and genetically modified colon epithelium. In this perspective, we discuss their findings in the context of what is currently known regarding the role of the mechanical landscape in cancer progression and β-catenin as a mechanotransducer. We review data that suggest that mechanically regulated activation of β-catenin fosters development of a malignant phenotype in tissue and predict that mechanical cues may contribute to tumor heterogeneity. PMID:26439949

  6. Unsaturated flow modeling of a retorted oil shale pile.

    SciTech Connect

    Bond, F.W.; Freshley, M.D.; Gee, G.W.

    1982-10-01

    The objective of this study was to demonstrate the capabilities of the UNSAT1D model for assessing this potential threat to the environment by understanding water movement through spent shale piles. Infiltration, redistribution, and drainage of water in a spent shale pile were simulated with the UNSAT1D model for two test cases: (1) an existing 35 m pile; and (2) a transient pile growing at a rate of 10 m/year for 5 years. The first test case simulated three different layering scenarios with each one being run for 1 year. The second test case simulated two different initial moisture contents in the pile with each simulation being run for 30 years. Grand Junction and Rifle, Colorado climatological data were used to provide precipitation and potential evapotranspiration for a wet (1979) and dry (1976) year, respectively. Hydraulic properties obtained from the literature on Paraho process spent shale soil, and clay were used as model input parameters to describe water retention and hydraulic conductivity characteristics. Plant water uptake was not simulated in either test case. The two test cases only consider the evaporation component of evapotranspiration, thereby maximizing the amount of water infiltrating into the pile. The results of the two test cases demonstrated that the UNSAT1D model can adequately simulate flow in a spent shale pile for a variety of initial and boundary conditions, hydraulic properties, and pile configurations. The test cases provided a preliminary sensitivity analysis in which it was shown that the material hydraulic properties, material layering, and initial moisture content are the principal parameters influencing drainage from the base of a pile. 34 figures, 4 tables.

  7. Reduction of a Redox-Active Ligand Drives Switching in a Cu(I) Pseudorotaxane by a Bimolecular Mechanism

    SciTech Connect

    McNitt, Kristy A.; Parimal, Kumar; Share, Andrew I.; Fahrenbach, Albert C.; Witlicki, Edward H.; Pink, Maren; Bediako, D. Kwabena; Plaisier, Christina L.; Le, Nga; Heeringa, Lee P.; Vander Griend, Douglas A.; Flood, Amar H.

    2009-04-02

    The reduction of a redox-active ligand is shown to drive reversible switching of a Cu(I) [2]pseudorotaxane ([2]PR{sup 2+}) into the reduced [3]pseudorotaxane ([3]PR{sup 2+}) by a bimolecular mechanism. The unreduced pseudorotaxanes [2]PR{sup 2+} and [3]PR{sup 2+} are initially self-assembled from the binucleating ligand, 3,6-bis(5-methyl-2-pyridine)-1,2,4,5-tetrazine (Me2BPTZ), and a preformed copper-macrocycle moiety (Cu-M{sup 2+}) based on 1,10-phenanthroline. X-ray crystallography revealed a syn geometry of the [3]PR{sup 2+}. The UV-vis-NIR spectra show low-energy metal-to-ligand charge-transfer transitions that red shift from 808 nm for [2]PR{sup 2+} to 1088 nm for [3]PR{sup 2+}. Quantitative analysis of the UV-vis-NIR titration shows the stepwise formation constants to be K{sub 1} = 8.9 x 10{sup 8} M{sup -1} and K{sub 2} = 3.1 x 10{sup 6} M{sup -1}, indicative of negative cooperativity. The cyclic voltammetry (CV) and coulometry of Me{sub 2}BPTZ, [2]PR{sup 2+}, and [3]PR{sup 2+} shows the one-electron reductions at E{sub 1/2} = -0.96, -0.65, and -0.285 V, respectively, to be stabilized in a stepwise manner by each Cu{sup 2+} ion. CVs of [2]PR{sup 2+} show changes with scan rate consistent with an EC mechanism of supramolecular disproportionation after reduction: [2]PR{sup 0} + [2]PR{sup 2+} = [3]PR{sup 2+} + Me{sub 2}BPTZ{sup 0} (K*{sub D}, k{sub d}). UV-vis-NIR spectroelectrochemistry was used to confirm the 1:1 product stoichiometry for [3]PR{sup 2+}:Me{sub 2}BPTZ. The driving force ({Delta}G*{sub D} = -5.1 kcal mol{sup -1}) for the reaction is based on the enhanced stability of the reduced [3]PR{sup 2+} over reduced [2]PR{sup 0} by 365 mV (8.4 kcal mol{sup -1}). Digital simulations of the CVs are consistent with a bimolecular pathway (k{sub d} = 12,000 s{sup -1} M{sup -1}). Confirmation of the mechanism provides a basis to extend this new switching modality to molecular machines.

  8. Piled tool will level subsea well template for Heidrun TLP

    SciTech Connect

    Not Available

    1992-01-13

    This paper reports on piled leveling tools that were contracted for use during the installation of the subsea well template for Conoco Norway Inc.'s Heidrun tension leg platform (TLP) in the Norwegian sector of the North Sea. The leveling tools are employed after a template has been positioned on the seafloor and anchor pilings have been driven through the template sleeves. One or more tools are lowered and landed on anchor pilings at the low side of the template. No diver support or guidelines are required.

  9. NK-, NKT- and CD8-Derived IFNγ Drives Myeloid Cell Activation and Erythrophagocytosis, Resulting in Trypanosomosis-Associated Acute Anemia.

    PubMed

    Cnops, Jennifer; De Trez, Carl; Stijlemans, Benoit; Keirsse, Jiri; Kauffmann, Florence; Barkhuizen, Mark; Keeton, Roanne; Boon, Louis; Brombacher, Frank; Magez, Stefan

    2015-06-01

    African trypanosomes are the causative agents of Human African Trypanosomosis (HAT/Sleeping Sickness) and Animal African Trypanosomosis (AAT/Nagana). A common hallmark of African trypanosome infections is inflammation. In murine trypanosomosis, the onset of inflammation occurs rapidly after infection and is manifested by an influx of myeloid cells in both liver and spleen, accompanied by a burst of serum pro-inflammatory cytokines. Within 48 hours after reaching peak parasitemia, acute anemia develops and the percentage of red blood cells drops by 50%. Using a newly developed in vivo erythrophagocytosis assay, we recently demonstrated that activated cells of the myeloid phagocytic system display enhanced erythrophagocytosis causing acute anemia. Here, we aimed to elucidate the mechanism and immune pathway behind this phenomenon in a murine model for trypanosomosis. Results indicate that IFNγ plays a crucial role in the recruitment and activation of erythrophagocytic myeloid cells, as mice lacking the IFNγ receptor were partially protected against trypanosomosis-associated inflammation and acute anemia. NK and NKT cells were the earliest source of IFNγ during T. b. brucei infection. Later in infection, CD8+ and to a lesser extent CD4+ T cells become the main IFNγ producers. Cell depletion and transfer experiments indicated that during infection the absence of NK, NKT and CD8+ T cells, but not CD4+ T cells, resulted in a reduced anemic phenotype similar to trypanosome infected IFNγR-/- mice. Collectively, this study shows that NK, NKT and CD8+ T cell-derived IFNγ is a critical mediator in trypanosomosis-associated pathology, driving enhanced erythrophagocytosis by myeloid phagocytic cells and the induction of acute inflammation-associated anemia. PMID:26070118

  10. NK-, NKT- and CD8-Derived IFNγ Drives Myeloid Cell Activation and Erythrophagocytosis, Resulting in Trypanosomosis-Associated Acute Anemia

    PubMed Central

    Cnops, Jennifer; De Trez, Carl; Stijlemans, Benoit; Keirsse, Jiri; Kauffmann, Florence; Barkhuizen, Mark; Keeton, Roanne; Boon, Louis; Brombacher, Frank; Magez, Stefan

    2015-01-01

    African trypanosomes are the causative agents of Human African Trypanosomosis (HAT/Sleeping Sickness) and Animal African Trypanosomosis (AAT/Nagana). A common hallmark of African trypanosome infections is inflammation. In murine trypanosomosis, the onset of inflammation occurs rapidly after infection and is manifested by an influx of myeloid cells in both liver and spleen, accompanied by a burst of serum pro-inflammatory cytokines. Within 48 hours after reaching peak parasitemia, acute anemia develops and the percentage of red blood cells drops by 50%. Using a newly developed in vivo erythrophagocytosis assay, we recently demonstrated that activated cells of the myeloid phagocytic system display enhanced erythrophagocytosis causing acute anemia. Here, we aimed to elucidate the mechanism and immune pathway behind this phenomenon in a murine model for trypanosomosis. Results indicate that IFNγ plays a crucial role in the recruitment and activation of erythrophagocytic myeloid cells, as mice lacking the IFNγ receptor were partially protected against trypanosomosis-associated inflammation and acute anemia. NK and NKT cells were the earliest source of IFNγ during T. b. brucei infection. Later in infection, CD8+ and to a lesser extent CD4+ T cells become the main IFNγ producers. Cell depletion and transfer experiments indicated that during infection the absence of NK, NKT and CD8+ T cells, but not CD4+ T cells, resulted in a reduced anemic phenotype similar to trypanosome infected IFNγR-/- mice. Collectively, this study shows that NK, NKT and CD8+ T cell-derived IFNγ is a critical mediator in trypanosomosis-associated pathology, driving enhanced erythrophagocytosis by myeloid phagocytic cells and the induction of acute inflammation-associated anemia. PMID:26070118

  11. Driving Method for Compensating Reliability Problem of Hydrogenated Amorphous Silicon Thin Film Transistors and Image Sticking Phenomenon in Active Matrix Organic Light-Emitting Diode Displays

    NASA Astrophysics Data System (ADS)

    Shin, Min-Seok; Jo, Yun-Rae; Kwon, Oh-Kyong

    2011-03-01

    In this paper, we propose a driving method for compensating the electrical instability of hydrogenated amorphous silicon (a-Si:H) thin film transistors (TFTs) and the luminance degradation of organic light-emitting diode (OLED) devices for large active matrix OLED (AMOLED) displays. The proposed driving method senses the electrical characteristics of a-Si:H TFTs and OLEDs using current integrators and compensates them by an external compensation method. Threshold voltage shift is controlled a using negative bias voltage. After applying the proposed driving method, the measured error of the maximum emission current ranges from -1.23 to +1.59 least significant bit (LSB) of a 10-bit gray scale under the threshold voltage shift ranging from -0.16 to 0.17 V.

  12. Pile mixing increases greenhouse gas emissions during composting of dairy manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of pile mixing on greenhouse gas (GHG) emissions from stored dairy manure was determined using large flux chambers designed to completely cover pilot-scale manure piles. GHG emissions from piles that were mixed four times during the 80 day trial were about 20% higher than unmixed piles. ...

  13. AKT activation drives the nuclear localization of CSE1L and a pro-oncogenic transcriptional activation in ovarian cancer cells

    SciTech Connect

    Lorenzato, Annalisa; Biolatti, Marta; Delogu, Giuseppe; Capobianco, Giampiero; Farace, Cristiano; Dessole, Salvatore; Cossu, Antonio; Tanda, Francesco; Madeddu, Roberto; Olivero, Martina; Di Renzo, Maria Flavia

    2013-10-15

    The human homolog of the yeast cse1 gene (CSE1L) is over-expressed in ovarian cancer. CSE1L forms complex with Ran and importin-α and has roles in nucleocytoplasmic traffic and gene expression. CSE1L accumulated in the nucleus of ovarian cancer cell lines, while it was localized also in the cytoplasm of other cancer cell lines. Nuclear localization depended on AKT, which was constitutively active in ovarian cancer cells, as the CSE1L protein translocated to the cytoplasm when AKT was inactivated. Moreover, the expression of a constitutively active AKT forced the translocation of CSE1L from the cytoplasm to the nucleus in other cancer cells. Nuclear accrual of CSE1L was associated to the nuclear accumulation of the phosphorylated Ran Binding protein 3 (RanBP3), which depended on AKT as well. Also in samples of human ovarian cancer, AKT activation was associated to nuclear accumulation of CSE1L and phosphorylation of RanBP3. Expression profiling of ovarian cancer cells after CSE1L silencing showed that CSE1L was required for the expression of genes promoting invasion and metastasis. In agreement, CSE1L silencing impaired motility and invasiveness of ovarian cancer cells. Altogether these data show that in ovarian cancer cells activated AKT by affecting RanBP3 phosphorylation determines the nuclear accumulation of CSE1L and likely the nuclear concentration of transcription factors conveying pro-oncogenic signals. - highlights: • CSE1L is a key player in nucleocytoplasmic traffic by forming complex with Ran. • AKT phosphorylates RanBP3 that regulates the nucleocytoplasmic gradient of Ran. • The activated oncogenic AKT drives the nuclear accumulation of CSE1L. • CSE1L in the nucleus up-regulates genes conveying pro-oncogenic signals. • CSE1L might contribute to tumor progression driven by the activated oncogenic AKT.

  14. Tally modifying of MCNP and post processing of pile-up simulation with time convolution method in PGNAA

    NASA Astrophysics Data System (ADS)

    Asghar Mowlavi, Ali; Koohi-Fayegh, Rahim

    2005-11-01

    Time convolution method has been employed for pile-up simulation in prompt gamma neutron activation analysis with an Am-Be neutron source and a 137Cs gamma source. A TALLYX subroutine has been written to design a new tally in the MCNP code. This tally records gamma particle information for the detector cell into an output file to be processed later. The times at which the particles are emitted by the source have been randomly generated following an exponential decay time distribution. A time convolution program was written to process the data produced and simulate more realistic pile-up. This method can be applied in optimization studies.

  15. Early corrosion monitoring of prestressed concrete piles using acoustic emission

    NASA Astrophysics Data System (ADS)

    Vélez, William; Matta, Fabio; Ziehl, Paul H.

    2013-04-01

    The depassivation and corrosion of bonded prestressing steel strands in concrete bridge members may lead to major damage or collapse before visual inspections uncover evident signs of damage, and well before the end of the design life. Recognizing corrosion in its early stage is desirable to plan and prioritize remediation strategies. The Acoustic Emission (AE) technique is a rational means to develop structural health monitoring and prognosis systems for the early detection and location of corrosion in concrete. Compelling features are the sensitivity to events related to micro- and macrodamage, non-intrusiveness, and suitability for remote and wireless applications. There is little understanding of the correlation between AE and the morphology and extent of early damage on the steel surface. In this paper, the evidence collected from prestressed concrete (PC) specimens that are exposed to salt water is discussed vis-à-vis AE data from continuous monitoring. The specimens consist of PC strips that are subjected to wet/dry salt water cycles, representing portions of bridge piles that are exposed to tidal action. Evidence collected from the specimens includes: (a) values of half-cell potential and linear polarization resistance to recognize active corrosion in its early stage; and (b) scanning electron microscopy micrographs of steel areas from two specimens that were decommissioned once the electrochemical measurements indicated a high probability of active corrosion. These results are used to evaluate the AE activity resulting from early corrosion.

  16. Three-dimensional finite element analysis of the interaction between tunneling and pile foundations

    NASA Astrophysics Data System (ADS)

    Mroueh, H.; Shahrour, I.

    2002-03-01

    This paper concerns analysis of the impact of construction of urban tunnels on adjacent pile foundations. It is carried out using an elastoplastic three-dimensional finite element modelling. Numerical simulations are performed in two stages, which concern, respectively, the application of the pile axial loading and the construction of the tunnel in presence of the pile foundations. Analysis is carried out for both single piles and groups of piles. Results of numerical simulations show that tunneling induces significant internal forces in adjacent piles. The distribution of internal forces depends mainly on the position of the pile tip regarding the tunnel horizontal axis and the distance of the pile axis from the centre of the tunnel. Analysis of the interaction between tunneling and a group of piles reveals a positive group effect with a high reduction of the internal forces in rear piles.

  17. 4. SULLIVAN TAILING PILE. CAMERA POINTED WEST. MINE ENTRANCE IS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. SULLIVAN TAILING PILE. CAMERA POINTED WEST. MINE ENTRANCE IS APPROXIMATELY 30 YARDS BEHIND CAMERA POSITION. - Florida Mountain Mining Sites, Sullivan Mine, East side of Florida Mountain, Silver City, Owyhee County, ID

  18. 96. DAM PILE SPACING PIER 4 TO PIER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    96. DAM - PILE SPACING - PIER 4 TO PIER 9 INCLUSIVE (ML-8-40/6-FS) June 1935 - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 8, On Mississippi River near Houston County, MN, Genoa, Vernon County, WI

  19. VIEW OF PROCESS DEVELOPMENT PILE (PDP) TANK TOP, WITH VERTICAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF PROCESS DEVELOPMENT PILE (PDP) TANK TOP, WITH VERTICAL ELEMENTS IN BACKGROUND, LEVEL 0’, LOOKING NORTHWEST - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC

  20. 52. VIEW SHOWING RAILROAD CRANEMOUNTED PILE DRIVER WORKING ON PIER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    52. VIEW SHOWING RAILROAD CRANE-MOUNTED PILE DRIVER WORKING ON PIER 2 OF SHOOFLY BRIDGE, LOOKING NORTHWEST FROM M STREET BRIDGE, December 28, 1934 - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

  1. 12. Underneath view of pilings and chain supports on sw ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Underneath view of pilings and chain supports on sw side near midsection; looking SE at low tide. - Pacific Creosoting Plant, West Dock, 5350 Creosote Place, Northeast, Bremerton, Kitsap County, WA

  2. 2. Pilings at end of Pier 11, low tide, view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Pilings at end of Pier 11, low tide, view to north. - Charlestown Navy Yard, Pier 11, Charlestown Waterfront at confluence of Little Mystic Channel & Mystic River at northernmost ent of Navy Yard, Boston, Suffolk County, MA

  3. 5. VIEW OF TIMBER PILES SUPPORTING GEORGIA DOT BRIDGE NO. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW OF TIMBER PILES SUPPORTING GEORGIA DOT BRIDGE NO. 111-00060P-00020N - Georgia DOT Bridge No. 111-00060P-00020N, Georgia State Route 60 spur spanning Hempton Creek, Mineral Bluff, Fannin County, GA

  4. 8. Roaring Fork Motor Nature Trail, handbuilt rock pile. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Roaring Fork Motor Nature Trail, hand-built rock pile. - Great Smoky Mountains National Park Roads & Bridges, Roaring Fork Motor Nature Trail, Between Cherokee Orchard Road & U.S. Route 321, Gatlinburg, Sevier County, TN

  5. 69. VIEW OF DECK AND PILINGS FROM LIFEGUARD TOWER AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    69. VIEW OF DECK AND PILINGS FROM LIFEGUARD TOWER AT 2ND TEE, LOOKING NORTH, SHOWING NEPTUNE'S LOCKER AND CAPTAIN'S GALLEY IN BACKGROUND AT RIGHT - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  6. As Traffic Piles Up, So Does Air Pollution

    MedlinePlus

    ... 160914.html As Traffic Piles Up, So Does Air Pollution To minimize exposure, researchers recommend shutting windows and ... Doing so can reduce your exposure to toxic air pollution from a traffic jam by up to 76 ...

  7. 1. GENERAL VIEW OF ENGINE PILE OF AGGREGATE AND MEN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL VIEW OF ENGINE PILE OF AGGREGATE AND MEN WAITING WITH WHEELBARROWS FILLED WITH AGGREGATE. TAKE DEC. 7, 1927. - Marsh Rainbow Arch Bridge, West Eighth Street North, Newton, Jasper County, IA

  8. Airborne thermography of temperature patterns in sugar beet piles

    NASA Technical Reports Server (NTRS)

    Moore, D. G.; Bichsel, S.

    1975-01-01

    An investigation was conducted to evaluate the use of thermography for locating spoilage areas (chimneys) within storage piles and to subsequently use the information for the scheduling of their processing. Thermal-infrared quantitative scanner data were acquired initially on January 16, 1975, over the storage piles at Moorhead, Minnesota, both during the day and predawn. Photographic data were acquired during the day mission to evaluate the effect of uneven snow cover on the thermal emittance, and the predawn thermography was used to locate potential chimneys. The piles were examined the day prior for indications of spoilage areas, and the ground crew indicated that no spoilage areas were located using their existing methods. Nine spoilage areas were interpreted from the thermography. The piles were rechecked by ground methods three days following the flights. Six of the nine areas delineated by thermography were actual spoilage areas.

  9. 33. Steampowered pile driver working on footings for Pier 3, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. Steam-powered pile driver working on footings for Pier 3, with south abutment visible at right; view to south. - Parks Bar Bridge, Spanning Yuba River at State Highway 20, Smartville, Yuba County, CA

  10. Biodeterioration of concrete piling in the Arabian Gulf

    SciTech Connect

    Jadkowski, T.K.; Wiltsie, E.A.

    1985-03-01

    Concrete is one of the most widely used materials in marine construction because of its characteristic durability in sea environments. Recent inspection of concrete piles installed in the Arabian Gulf has revealed that concrete with high content of calcareous aggregate is susceptible to biodeterioration. Marine rock borers and sponges, which are common in areas where the seabed is composed of limestone rock, have been identified as the marine species responsible for the biodeterioration. Boring organisms pose a significant threat to concrete pile structural integrity. Boreholes deteriorate concrete and expose outer pile reinforcement to seawater. This paper describes the causes and magnitude of biodeterioration of piles installed in the Arabian Gulf and presents design parameters and material specifications for the selected preventive repair system.

  11. 4. West side of pier showing distinct piling configuration. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. West side of pier showing distinct piling configuration. - Charlestown Navy Yard, Pier 10, Between Piers 9 & 11 along Mystic River on Charlestown Waterfront at eastern edge of Charlestown Navy Yard, Boston, Suffolk County, MA

  12. VIEW OF SOUTHERN QUARRY, FACING SOUTH, WITH ROCK PILES IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF SOUTHERN QUARRY, FACING SOUTH, WITH ROCK PILES IN FOREGROUND - Granite Hill Plantation, Quarry No. 2, South side of State Route 16, 1.3 miles northeast east of Sparta, Sparta, Hancock County, GA

  13. 93. VIEW OF PILINGS ON SOUTHEAST SIDE, FACING NORTH FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    93. VIEW OF PILINGS ON SOUTHEAST SIDE, FACING NORTH FROM SOUTHEAST SIDE OF 4TH TEE, SHOWING RESTROOMS, PUMPHOUSE, AND THE TACKLE BOX IN BACKGROUND - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  14. Processing Satellite Imagery To Detect Waste Tire Piles

    NASA Technical Reports Server (NTRS)

    Skiles, Joseph; Schmidt, Cynthia; Wuinlan, Becky; Huybrechts, Catherine

    2007-01-01

    A methodology for processing commercially available satellite spectral imagery has been developed to enable identification and mapping of waste tire piles in California. The California Integrated Waste Management Board initiated the project and provided funding for the method s development. The methodology includes the use of a combination of previously commercially available image-processing and georeferencing software used to develop a model that specifically distinguishes between tire piles and other objects. The methodology reduces the time that must be spent to initially survey a region for tire sites, thereby increasing inspectors and managers time available for remediation of the sites. Remediation is needed because millions of used tires are discarded every year, waste tire piles pose fire hazards, and mosquitoes often breed in water trapped in tires. It should be possible to adapt the methodology to regions outside California by modifying some of the algorithms implemented in the software to account for geographic differences in spectral characteristics associated with terrain and climate. The task of identifying tire piles in satellite imagery is uniquely challenging because of their low reflectance levels: Tires tend to be spectrally confused with shadows and deep water, both of which reflect little light to satellite-borne imaging systems. In this methodology, the challenge is met, in part, by use of software that implements the Tire Identification from Reflectance (TIRe) model. The development of the TIRe model included incorporation of lessons learned in previous research on the detection and mapping of tire piles by use of manual/ visual and/or computational analysis of aerial and satellite imagery. The TIRe model is a computational model for identifying tire piles and discriminating between tire piles and other objects. The input to the TIRe model is the georeferenced but otherwise raw satellite spectral images of a geographic region to be surveyed

  15. The equivalence between dislocation pile-ups and cracks

    NASA Technical Reports Server (NTRS)

    Liu, H. W.; Gao, Q.

    1990-01-01

    Cracks and dislocation pile-ups are equivalent to each other. In this paper, the physical equivalence between cracks and pile-ups is delineated, and the relationshps between crack-extension force, force on the leading dislocation, stress-intensity factor, and dislocation density are reviewed and summarized. These relations make it possible to extend quantitatively the recent advances in the concepts and practices of fracture mechanics to the studies of microfractures and microplastic deformations.

  16. Zinc mesh anodes cast into concrete pile jackets

    SciTech Connect

    Kessler, R.J.; Powers, R.G.; Lasa, I.R.

    1996-12-01

    A sacrificial cathodic protection system has been designed to provide corrosion control to the splash area and the submerged portion of reinforced concrete bridge pilings. The system consists of a two-piece stay-in-place fiberglass form with an internal expanded zinc mesh anode. It is filled with a portland cement-sand mortar to protect the splash area. The submerged portion of the pile is protected using a standard zinc bulk anode.

  17. Conoco installs eight-pile rig on four-pile platform

    SciTech Connect

    Albaugh, E.K.

    1983-11-01

    Rig 122 recently became the largest standard self-contained drilling rig ever to be mounted on a four-pile, tender-style platform. The conversion sacrificed none of the rig's deep drilling capability, and enabled Conoco to utilize a self-contained platform drilling rig on a satellite platform in the same field. Two cantilever beams, extending some 42 ft beyond platform columns on two sides, support rig weight. Modifications to the rig include separation of pump and engine packages, a pipe-rack extension and a novel skidding system.

  18. Slime thickness evaluation of bored piles by electrical resistivity probe

    NASA Astrophysics Data System (ADS)

    Chun, Ok-Hyun; Yoon, Hyung-Koo; Park, Min-Chul; Lee, Jong-Sub

    2014-09-01

    The bottoms of bored piles are generally stacked with soil particles, both while boreholes are being drilled, and afterward. The stacked soils are called slime, and when loads are applied on the pile, increase the pile settlement. Thus to guarantee the end bearing capacity of bored piles, the slime thickness should be precisely detected. The objective of this study is to suggest a new method for evaluating the slime thickness, using temperature compensated electrical resistivity. Laboratory studies are performed in advance, to estimate and compare the resolution of the electrical resistivity probe (ERP) and time domain reflectometry (TDR). The electrical properties of the ERP and TDR are measured using coaxial type electrodes and parallel type two-wire electrodes, respectively. Penetration tests, conducted in the fully saturated sand-clay mixtures, demonstrate that the ERP produces a better resolution of layer detection than TDR. Thus, field application tests using the ERP with a diameter of 35.7 mm are conducted for the investigation of slime thickness in large diameter bored piles. Field tests show that the slime layers are clearly identified by the ERP: the electrical resistivity dramatically increases at the interface between the slurry and slime layer. The electrical resistivity in the slurry layer inversely correlates with the amount of circulated water. This study suggests that the new electrical resistivity method may be a useful method for the investigation of the slime thickness in bored piles.

  19. The Supercritical Pile Model for GRBs

    NASA Technical Reports Server (NTRS)

    Kazanas, D.

    2005-01-01

    We present the spectral and temporal radiative signatures expected within the "Supercritical Pile" model of Gamma Ray Bursts (GRB). This model is motivated by the need for a process that provides the dissipation necessary in GRB and presents a well defined scheme for converting the energy stored in the relativistic protons of the Relativistic Blast Waves (RBW) associated with GRB into radiation; at the same time it leads to spectra which exhibit a peak in the burst nuF(sub nu) distribution at an energy E(sub p) approx. equal to 1 MeV in the observer s frame, in agreement with observation and largely independent of the Lorentz factor r of the associated relativistic outflow. Futhermore, this scheme does not require (but does not preclude) acceleration of particles at the shock other than that provided by the isotropization of the flow bulk kinetic energy on the RBW frame. In the present paper we model in detail the evolution of protons, electrons and photons from a RBW to produce detailed spectra of the prompt GRB phase as a function of time from across a very broad range spanning roughly 4 log10Gamma decades in frequency. The model spectra are in general agreement with observations and provide a means for the delineating of the model parameters through direct comparison with trends observed in GRB properties.

  20. Structural stability of rubble-pile asteroids

    NASA Astrophysics Data System (ADS)

    Sharma, Ishan

    2013-03-01

    Granular aggregates, like fluids, do not admit all manners of shapes and rotation rates. It is hoped that an analysis of a suspected granular asteroid’s equilibrium shape and its structural stability will help confirm its rubble-pile nature, and, perhaps, even constrain the asteroid’s material parameters. Equilibrium shapes have been analyzed in the past by several investigators (Holsapple, K.A. [2001]. Icarus 154, 432-448; Harris, A.W., Fahnestock, E.G., Pravec, P. [2009]. Icarus 199, 310-318; Sharma, I., Jenkins, J.T., Burns, J.A. [2009]. Icarus 200, 304-322). Here, we extend the classical Lagrange-Dirichlet stability theorem to the case of self-gravitating granular aggregates. This stability test is then applied to probe the stability of several near-Earth asteroids, and explore the influence of material parameters such as internal friction angle and plastic bulk modulus. Finally, we consider their structural stability to close planetary encounters. We find that it is possible for asteroids to be stable to small perturbations, but unstable to strong and/or extended perturbations as experienced during close flybys. Conversely, assuming stability in certain situations, it is possible to estimate material properties of some asteroids like, for example, 1943 Anteros.

  1. The Supercritical Pile Model for GRBs

    NASA Astrophysics Data System (ADS)

    Mastichiadis; Kazanas

    2006-02-01

    We present the spectral and temporal radiative signatures expected withinthe quot;Supercritical Pile\\" model of Gamma Ray Bursts (GRB). This modelis motivated by the need for a process that provides the dissipationnecessary in GRB and presents a well defined scheme for converting theenergy stored in the relativistic protons of theRelativistic Blast Waves (RBW) associated with GRB into radiation; at thesame time it leads to spectra which exhibit a peak in the burst nuF_{nu} distribution at an energy E_p simeq 1 MeV in theobserverapos;s frame, in agreement with observation and largelyindependent of the Lorentz factor Gamma of the associated relativisticoutflow. Futhermore, this scheme does not require (but does notpreclude) acceleration of particles at the shock other than that providedby the isotropization of the flow bulk kinetic energy on the RBW frame. Inthe present paper we model in detail the evolution of protons, electronsand photons from a RBW within the framework of this model to producedetailed spectra of the prompt GRB phase as a function of time from acrossa very broad range spanning roughly 4 log_{10} Gamma decades$ in frequency. The model spectra are in generalagreement with observations and provide a means for the delineating of themodel parameters through direct comparison with trends observed in GRBproperties.

  2. Preliminary report on coal pile, coal pile runoff basins, and ash basins at the Savannah River Site: effects on groundwater

    SciTech Connect

    Palmer, E.

    1997-04-28

    Coal storage piles, their associated coal pile runoff basins and ash basins could potentially have adverse environmental impacts, especially on groundwater. This report presents and summarizes SRS groundwater and soil data that have been compiled. Also, a result of research conducted on the subject topics, discussions from noted experts in the field are cited. Recommendations are made for additional monitor wells to be installed and site assessments to be conducted.

  3. Parametric study on the effects of pile inclination angle on the response of batter piles in offshore jacket platforms

    NASA Astrophysics Data System (ADS)

    Aminfar, Ali; Ahmadi, Hamid; Aminfar, Mohammad Hossein

    2016-06-01

    Offshore jacket-type platforms are attached to the seabed by long batter piles. In this paper, results from a finite element analysis, verified against experimental data, are used to study the effect of the pile's inclination angle, and its interaction with the geometrical properties of the pile and the geotechnical characteristics of the surrounding soil on the behavior of the inclined piles supporting the jacket platforms. Results show that the inclination angle is one of the main parameters affecting the behavior of an offshore pile. We investigated the effect of the inclination angle on the maximum von Mises stress, maximum von Mises elastic strain, maximum displacement vector sum, maximum displacement in the horizontal direction, and maximum displacement in the vertical direction. The pile seems to have an operationally optimal degree of inclination of approximately 5°. By exceeding this value, the instability in the surrounding soil under applied loads grows extensively in all the geotechnical properties considered. Cohesive soils tend to display poorer results compared to grained soils.

  4. Parametric study on the effects of pile inclination angle on the response of batter piles in offshore jacket platforms

    NASA Astrophysics Data System (ADS)

    Aminfar, Ali; Ahmadi, Hamid; Aminfar, Mohammad Hossein

    2016-04-01

    Offshore jacket-type platforms are attached to the seabed by long batter piles. In this paper, results from a finite element analysis, verified against experimental data, are used to study the effect of the pile's inclination angle, and its interaction with the geometrical properties of the pile and the geotechnical characteristics of the surrounding soil on the behavior of the inclined piles supporting the jacket platforms. Results show that the inclination angle is one of the main parameters affecting the behavior of an offshore pile. We investigated the effect of the inclination angle on the maximum von Mises stress, maximum von Mises elastic strain, maximum displacement vector sum, maximum displacement in the horizontal direction, and maximum displacement in the vertical direction. The pile seems to have an operationally optimal degree of inclination of approximately 5°. By exceeding this value, the instability in the surrounding soil under applied loads grows extensively in all the geotechnical properties considered. Cohesive soils tend to display poorer results compared to grained soils.

  5. Characterization of Odorant Compounds from Mechanical Aerated Pile Composting and Static Aerated Pile Composting.

    PubMed

    Kumari, Priyanka; Lee, Joonhee; Choi, Hong-Lim

    2016-04-01

    We studied airborne contaminants (airborne particulates and odorous compounds) emitted from compost facilities in South Korea. There are primarily two different types of composting systems operating in Korean farms, namely mechanical aerated pile composting (MAPC) and aerated static pile composting (SAPC). In this study, we analyzed various particulate matters (PM10, PM7, PM2.5, PM1, and total suspended particles), volatile organic compounds and ammonia, and correlated these airborne contaminants with microclimatic parameters, i.e., temperature and relative humidity. Most of the analyzed airborne particulates (PM7, PM2.5, and PM1) were detected in high concentration at SAPC facilities compered to MAPC; however these differences were statistically non-significant. Similarly, most of the odorants did not vary significantly between MAPC and SAPC facilities, except for dimethyl sulfide (DMS) and skatole. DMS concentrations were significantly higher in MAPC facilities, whereas skatole concentrations were significantly higher in SAPC facilities. The microclimate variables also did not vary significantly between MAPC and SAPC facilities, and did not correlate significantly with most of the airborne particles and odorous compounds, suggesting that microclimate variables did not influence their emission from compost facilities. These findings provide insight into the airborne contaminants that are emitted from compost facilities and the two different types of composting agitation systems. PMID:26949962

  6. Characterization of Odorant Compounds from Mechanical Aerated Pile Composting and Static Aerated Pile Composting

    PubMed Central

    Kumari, Priyanka; Lee, Joonhee; Choi, Hong-Lim

    2016-01-01

    We studied airborne contaminants (airborne particulates and odorous compounds) emitted from compost facilities in South Korea. There are primarily two different types of composting systems operating in Korean farms, namely mechanical aerated pile composting (MAPC) and aerated static pile composting (SAPC). In this study, we analyzed various particulate matters (PM10, PM7, PM2.5, PM1, and total suspended particles), volatile organic compounds and ammonia, and correlated these airborne contaminants with microclimatic parameters, i.e., temperature and relative humidity. Most of the analyzed airborne particulates (PM7, PM2.5, and PM1) were detected in high concentration at SAPC facilities compered to MAPC; however these differences were statistically non-significant. Similarly, most of the odorants did not vary significantly between MAPC and SAPC facilities, except for dimethyl sulfide (DMS) and skatole. DMS concentrations were significantly higher in MAPC facilities, whereas skatole concentrations were significantly higher in SAPC facilities. The microclimate variables also did not vary significantly between MAPC and SAPC facilities, and did not correlate significantly with most of the airborne particles and odorous compounds, suggesting that microclimate variables did not influence their emission from compost facilities. These findings provide insight into the airborne contaminants that are emitted from compost facilities and the two different types of composting agitation systems. PMID:26949962

  7. An investigation into the effects of underwater piling noise on salmonids.

    PubMed

    Nedwell, Jeremy R; Turnpenny, Andrew W H; Lovell, Jonathan M; Edwards, Bryan

    2006-11-01

    Underwater piling was undertaken in 2003 in Southampton Water on the South Coast of England. Monitoring was simultaneously undertaken of the waterborne sound from impact and vibropiling and its effects on brown trout in cages at increasing distances from the piling. Brown trout (Salmo trutta) were used as a model for salmon (Salmo salar), which were the species of interest but were not readily available. No obvious signs of trauma that could be attributed to sound exposure were found in any fish examined, from any of the cages. No increase in activity or startle response was seen to vibropiling. Analysis using the dBh, metric indicated that the noise at the nearest cages during impact piling reached levels at which salmon were expected to react strongly. However, the brown trout showed little reaction. An audiogram of the brown trout was measured by the Auditory Brainstem Response method, which indicated that the hearing of the brown trout was less sensitive than that of the salmon. Further analysis indicated that this accounted for the relative lack of reaction, and demonstrated the importance of using the correct species of fish as a model when assessing the effect of noise. PMID:17139717

  8. Dynamic load testing on the bearing capacity of prestressed tubular concrete piles in soft ground

    NASA Astrophysics Data System (ADS)

    Yu, Chuang; Liu, Songyu

    2008-11-01

    Dynamic load testing (DLT) is a high strain test method for assessing pile performance. The shaft capacity of a driven PTC (prestressed tubular concrete) pile in marine soft ground will vary with time after installation. The DLT method has been successfully transferred to the testing of prestressed pipe piles in marine soft clay of Lianyungang area in China. DLT is investigated to determine the ultimate bearing capacity of single pile at different period after pile installation. The ultimate bearing capacity of single pile was founded to increase more than 70% during the inventing 3 months, which demonstrate the time effect of rigid pile bearing capacity in marine soft ground. Furthermore, the skin friction and axial force along the pile shaft are presented as well, which present the load transfer mechanism of pipe pile in soft clay. It shows the economy and efficiency of DLT method compared to static load testing method.

  9. Seismic response of tall building considering soil-pile-structure interaction

    NASA Astrophysics Data System (ADS)

    Han, Yingcai

    2002-06-01

    The seismic behavior of tall buildings can be greatly affected by non-linear soil-pile interaction during strong earthquakes. In this study a 20-storey building is examined as a typical structure supported on a pile foundation for different conditions: (1) rigid base, i.e. no deformation in the foundation: (2) linear soil-pile system; and (3) nonlinear soil-pile system. The effects of pile foundation displacements on the behavior of tall building are investigated, and compared with the behavior of buildings supported on shallow foundation. With a model of non-reflective boundary between the near field and far field, Novak’s method of soil-pile interaction is improved. The computation method for vibration of pile foundations and DYNAN computer program are introduced comprehensively. A series of dynamic experiments have been done on full-scale piles, including single pile and group, linear vibration and nonlinear vibration, to verify the validity of boundary zone model.

  10. Numerical experiments with rubble piles: equilibrium shapes and spins

    NASA Astrophysics Data System (ADS)

    Richardson, Derek C.; Elankumaran, Pradeep; Sanderson, Robyn E.

    2005-02-01

    We present numerical experiments investigating the shape and spin limits of self-gravitating "perfect" rubble piles that consist of identical, smooth, rigid, spherical particles with configurable normal coefficient of restitution and no sliding friction. Such constructs are currently employed in a variety of investigations, ranging from the formation of asteroid satellites to the dynamical properties of Saturn's densest rings. We find that, owing to cannonball stacking behavior, rubble piles can maintain non-spherical shapes without bulk spin, unlike a fluid, and can spin faster than a perfect fluid before shedding mass, consistent with the theory for the more general continuum rubble pile model (Holsapple, 2004, Icarus 172, 272-303). Rubble piles that reassemble following a catastrophic disruption reconfigure themselves to lie within stability limits predicted by the continuum theory. We also find that coarse configurations consisting of a small number of particles are more resistant to tidal disruption than fine configurations with many particles. Overall this study shows that idealized rubble piles behave qualitatively in a manner similar to certain granular materials, at least in the limit where global shape readjustments and/or mass shedding begins. The limits obtained here may provide constraints on the possible internal structure of some small Solar System bodies that have extreme shapes or are under high stress. Amalthea is presented as a case study.

  11. CSI: Hard Drive

    ERIC Educational Resources Information Center

    Sturgeon, Julie

    2008-01-01

    Acting on information from students who reported seeing a classmate looking at inappropriate material on a school computer, school officials used forensics software to plunge the depths of the PC's hard drive, searching for evidence of improper activity. Images were found in a deleted Internet Explorer cache as well as deleted file space.…

  12. Cumulative Damage in Strength-Dominated Collisions of Rocky Asteroids: Rubble Piles and Brick Piles

    NASA Technical Reports Server (NTRS)

    Housen, Kevin

    2009-01-01

    Laboratory impact experiments were performed to investigate the conditions that produce large-scale damage in rock targets. Aluminum cylinders (6.3 mm diameter) impacted basalt cylinders (69 mm diameter) at speeds ranging from 0.7 to 2.0 km/s. Diagnostics included measurements of the largest fragment mass, velocities of the largest remnant and large fragments ejected from the periphery of the target, and X-ray computed tomography imaging to inspect some of the impacted targets for internal damage. Significant damage to the target occurred when the kinetic energy per unit target mass exceeded roughly 1/4 of the energy required for catastrophic shattering (where the target is reduced to one-half its original mass). Scaling laws based on a rate-dependent strength were developed that provide a basis for extrapolating the results to larger strength-dominated collisions. The threshold specific energy for widespread damage was found to scale with event size in the same manner as that for catastrophic shattering. Therefore, the factor of four difference between the two thresholds observed in the lab also applies to larger collisions. The scaling laws showed that for a sequence of collisions that are similar in that they produce the same ratio of largest fragment mass to original target mass, the fragment velocities decrease with increasing event size. As a result, rocky asteroids a couple hundred meters in diameter should retain their large ejecta fragments in a jumbled rubble-pile state. For somewhat larger bodies, the ejection velocities are sufficiently low that large fragments are essentially retained in place, possibly forming ordered "brick-pile" structures.

  13. The drive-wise project: driving simulator training increases real driving performance in healthy older drivers

    PubMed Central

    Casutt, Gianclaudio; Theill, Nathan; Martin, Mike; Keller, Martin; Jäncke, Lutz

    2014-01-01

    Background: Age-related cognitive decline is often associated with unsafe driving behavior. We hypothesized that 10 active training sessions in a driving simulator increase cognitive and on-road driving performance. In addition, driving simulator training should outperform cognitive training. Methods: Ninety-one healthy active drivers (62–87 years) were randomly assigned to one of three groups: (1) a driving simulator training group, (2) an attention training group (vigilance and selective attention), or (3) a control group. The main outcome variables were on-road driving and cognitive performance. Seventy-seven participants (85%) completed the training and were included in the analyses. Training gains were analyzed using a multiple regression analysis with planned orthogonal comparisons. Results: The driving simulator-training group showed an improvement in on-road driving performance compared to the attention-training group. In addition, both training groups increased cognitive performance compared to the control group. Conclusion: Driving simulator training offers the potential to enhance driving skills in older drivers. Compared to the attention training, the simulator training seems to be a more powerful program for increasing older drivers' safety on the road. PMID:24860497

  14. A simple approach for calculating pile skin friction in clays

    SciTech Connect

    Mirza, U.A.A.

    1995-12-31

    A simple method is presented for calculating static shaft resistance of a pile driven into clay. The method is based on correlations established for North Sea clays between index properties and strengths. Application of the method to half a dozen full scale pile load tests which are part of the API RP2A`s data base and include a wide range of plasticity properties, overconsolidation ratios and strengths, is described. Except for short piles in very stiff to hard clays, the predictions agree very well with the measurements. The correlations presented allows an assessment of residual skin friction and indicate the importance of the liquidity index of the clay in static capacity calculations.

  15. Design of Jetty Piles Using Artificial Neural Networks

    PubMed Central

    2014-01-01

    To overcome the complication of jetty pile design process, artificial neural networks (ANN) are adopted. To generate the training samples for training ANN, finite element (FE) analysis was performed 50 times for 50 different design cases. The trained ANN was verified with another FE analysis case and then used as a structural analyzer. The multilayer neural network (MBPNN) with two hidden layers was used for ANN. The framework of MBPNN was defined as the input with the lateral forces on the jetty structure and the type of piles and the output with the stress ratio of the piles. The results from the MBPNN agree well with those from FE analysis. Particularly for more complex modes with hundreds of different design cases, the MBPNN would possibly substitute parametric studies with FE analysis saving design time and cost. PMID:25177724

  16. Localized cathodic protection of simulated prestressed concrete pilings in seawater

    SciTech Connect

    Chaix, O.; Hartt, W.H.; Kessler, R.; Powers, R.

    1995-05-01

    Corrosion-induced deterioration of prestressed concrete pilings in seawater has been established as the predominant failure mode. A technology involving localized impressed-current cathodic protection (CP) of the splash-zone region in association with conductive rubber anodes was developed to mitigate this deterioration. A series of experiments involving cathodic polarization of simulated prestressed concrete piling specimens partially immersed in seawater was performed. Variables included the concrete mix design, specimen cross section, anode dimensions, and water level. An interactive aspect of CP-operating parameters in association with water level was identified as important if excessively negative potentials and possible tendon embrittlement were to be avoided. The data were evaluated with regard to the interdependence between depolarization magnitude, potential, and concrete relative humidity. Results were reviewed within the context of CP utility for prestressed concrete bridge piling.

  17. Mental workload and driving

    PubMed Central

    Paxion, Julie; Galy, Edith; Berthelon, Catherine

    2014-01-01

    The aim of this review is to identify the most representative measures of subjective and objective mental workload in driving, and to understand how the subjective and objective levels of mental workload influence the performance as a function of situation complexity and driving experience, i.e., to verify whether the increase of situation complexity and the lack of experience increase the subjective and physiological levels of mental workload and lead to driving performance impairments. This review will be useful to both researchers designing an experimental study of mental workload and to designers of drivers’ training content. In the first part, we will broach the theoretical approach with two factors of mental workload and performance, i.e., situation complexity and driving experience. Indeed, a low complex situation (e.g., highways), or conversely a high complex situation (e.g., town) can provoke an overload. Additionally, performing the driving tasks implies producing a high effort for novice drivers who have not totally automated the driving activity. In the second part, we will focus on subjective measures of mental workload. A comparison of questionnaires usually used in driving will allow identifying the most appropriate ones as a function of different criteria. Moreover, we will review the empirical studies to verify if the subjective level of mental workload is high in simple and very complex situations, especially for novice drivers compared to the experienced ones. In the third part, we will focus on physiological measures. A comparison of physiological indicators will be realized in order to identify the most correlated to mental workload. An empirical review will also take the effect of situation complexity and experience on these physiological indicators into consideration. Finally, a more nuanced comparison between subjective and physiological measures will be established from the impact on situation complexity and experience. PMID:25520678

  18. Controlling Cost Growth in PI-led Missions

    NASA Astrophysics Data System (ADS)

    Harrison, Fiona

    2014-08-01

    While the cost and schedule performance of PI-led competed missions is better than that of strategic missions, the majority of PI-led missions have experienced increases relative to their initial proposed cost. I will review the performance of competed missions, comparing them to flagship observatories. I will describe in general reasons for cost growth starting from assumptions made at the proposal stage to challenges with technology development, technical implementation and management. I will also describe strategies for effective implementation that can be used to manage cost growth.

  19. Thermocouples For High Temperature In-Pile Testing

    SciTech Connect

    J. L. Rempe

    2005-11-01

    Many advanced nuclear reactor designs require new fuel, cladding and structural materials. Data are needed to characeterize the performance of these new materials in high temperature, oxidizing and radiation conditions. To obtain this data, robust instrumentation is needed htat can survive proposed test conditions. Traditional methods for measuring temperature in-pile degrade at temperatures above 1080 degrees C. Hence, a project was intiated to develop specialized thermocouples for high temperature in-pile applications (see Rempe and Wilkins, 2005). This paper summarizes efforts to develop, fabricate and evaluate these specialized thermocouples.

  20. 27. The top of a typical pile, F Reactor in ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. The top of a typical pile, F Reactor in February 1945 in this case, showing the vertical safety rods (VSRs) and the cables that support them. The rods could be dropped into the pile to effect a rapid shutdown. The four silvered-colored drums on the left contained boron solution and are part of the last ditch safety system. Should the VSRs channels become blocked by an occurrence such as an earthquake, the solution could be dumped into the VSR channels to help shut down the reactor. D-8334 - B Reactor, Richland, Benton County, WA

  1. Field chronobiology of a molluscan bivalve: how the moon and sun cycles interact to drive oyster activity rhythms.

    PubMed

    Tran, Damien; Nadau, Arnaud; Durrieu, Gilles; Ciret, Pierre; Parisot, Jean-Paul; Massabuau, Jean-Charles

    2011-05-01

    The present study reports new insights into the complexity of environmental drivers in aquatic animals. The focus of this study was to determine the main forces that drive mollusc bivalve behavior in situ. To answer this question, the authors continuously studied the valve movements of permanently immersed oysters, Crassostrea gigas, during a 1-year-long in situ study. Valve behavior was monitored with a specially build valvometer, which allows continuously recording of up to 16 bivalves at high frequency (10 Hz). The results highlight a strong relationship between the rhythms of valve behavior and the complex association of the sun-earth-moon orbital positions. Permanently immersed C. gigas follows a robust and strong behavior primarily driven by the tidal cycle. The intensity of this tidal driving force is modulated by the neap-spring tides (i.e., synodic moon cycle), which themselves depend of the earth-moon distance (i.e., anomalistic moon cycle). Light is a significant driver of the oysters' biological rhythm, although its power is limited by the tides, which remain the predominant driver. More globally, depending where in the world the bivalves reside, the results suggest their biological rhythms should vary according to the relative importance of the solar cycle and different lunar cycles associated with tide generation. These results highlight the high plasticity of these oysters to adapt to their changing environment. PMID:21539422

  2. Dementia and driving

    MedlinePlus

    ... not drive at times of the day when traffic is heaviest. Do not drive when the weather is bad. Do not drive long distances. Drive only on roads the person is used to. Caregivers should try to lessen ...

  3. Critical load and buckling of the single pile foundation subjected to the vertical load

    NASA Astrophysics Data System (ADS)

    Ma, Jianjun; Peng, Jian; Wang, Lianhua; Zhao, Yueyu

    2013-07-01

    In this study, the critical load and buckling of the single pile foundation subjected to the vertical load are investigated. Considering the second-order moment of the soil-structure interaction, the refined model of the single pile foundation is derived. Then, the critical load and buckling phenomenon of the single pile foundation is examined. Moreover, the effects of the vertical load and the foundation parameters on the critical load and buckling of the single pile foundation are systematically investigated.

  4. Alteration and arenization processes of granitic waste rock piles from former uranium Mines in Limousin, France.

    NASA Astrophysics Data System (ADS)

    Kanzari, Aisha; Boekhout, Flora; Gérard, Martine; Galoisy, Laurence; Phrommavanh, Vannapha; Descostes, Michael

    2014-05-01

    France counts approximately 200 former uranium mines, 50 of which are located in the Limousin region. Mining activities between 1945 and 2001 have generated close to 200 000 tons of waste rocks in the Limousin, with uranium levels corresponding essentially to the geological background. Waste rock piles from three former mining sites in this region, were selected according to their age, uranium content and petrological signature. These sites are part of the two-mica granitic complex of St Sylvestre massif, formed 324 million years ago. Granitic blocks that build up the waste rock piles have experienced different processes and intensities of alteration before their emplacement at the surface. These processes are responsible for the petrological heterogeneity throughout the waste rock pile at the time of construction. It is important to make a distinction within waste rocks between natural-cut-off waste rocks and economic-cut-off waste rocks. The latter represents a minority and is linked to stock prices. Natural-cut-off waste rocks contain about 20 ppm of uranium; economic-cut-off waste rocks contain about 100 to 300 ppm of uranium. The aims of this study are to 1) assess the neo-formation of U-bearing minerals hosted by these rocks, and 2) to characterize the weathering processes since the construction of the rock piles, including both mechanical and chemical processes. The structure of the waste rocks piles, from metric blocks to boulders of tens centimeters, induces an enhanced weathering rate, compared to a granitic massif. Mechanical fracturing and chemical leaching by rainwater (arenization) of the waste rocks produce a sandy-silty alteration phase. Silty-clay weathering aureoles of submetric-granitic blocks evolving into technic soil are mainly located below growing birch trees. Sampling on the rock piles was restricted to surface rocks. Samples collected consist mainly of granites, and rare lamprophyres with a high radiometric signal, thereby especially

  5. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  6. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  7. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  8. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  9. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  10. Greenhouse gas emissions during composting of dairy manure: Delaying pile mixing does not reduce overall emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of the timing of pile mixing on greenhouse gas (GHG) emissions during dairy manure composting was determined using large flux chambers designed to completely cover replicate pilot-scale compost piles. GHG emissions from compost piles that were mixed at 2, 3, 4, or 5 weeks after initial c...

  11. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... outslope of the refuse pile if required for stability, control or erosion, conservation of soil moisture... weather seeps, the design shall include diversions and underdrains as necessary to control erosion... area stabilization. Slope protection shall be provided to minimize surface erosion at the site....

  12. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... outslope of the refuse pile if required for stability, control of erosion, conservation of soil moisture... weather seeps, the design shall include diversions and underdrains as necessary to control erosion... area stabilization. Slope protection shall be provided to minimize surface erosion at the site....

  13. 61. Picking Floor, Large Pile of Waste Rock and Wood ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    61. Picking Floor, Large Pile of Waste Rock and Wood date unknown Historic Photograph, Photographer Unknown; Collection of William Everett, Jr. (Wilkes-Barre, PA), photocopy by Joseph E.B. Elliot - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA

  14. 5. VIEW OF UPPER NOTTINGHAM TAILING PILES LOOKING TOWARDS ROCK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW OF UPPER NOTTINGHAM TAILING PILES LOOKING TOWARDS ROCK WALL VISIBLE ON SLOPE JUST RIGHT OF CENTER. CAMERA POINTED SOUTHEAST. - Florida Mountain Mining Sites, Upper Nottingham Mine, West face of Florida Mountain, head of Jacobs Gulch, Silver City, Owyhee County, ID

  15. OVERVIEW OF CYANIDE PLANT REMAINS, TAILINGS PILES, PARKING LOT, AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    OVERVIEW OF CYANIDE PLANT REMAINS, TAILINGS PILES, PARKING LOT, AND MINE MANAGER'S HOME, LOOKING SOUTH SOUTHEAST. RIGHT, TAILINGS PILES ARE AT CENTER WITH CYANIDE PLANT FOUNDATIONS TO THE LEFT OF THE PILES. PARKING LOT IS AT UPPER LEFT. THE AREA BETWEEN THE COLLAPSED TANK AT CENTER LEFT AND THE REMAINS OF THE MANAGER'S HOUSE AT LOWER RIGHT IS A TAILINGS HOLDING AREA. TAILINGS FROM THE MILL WERE HELD HERE. THE LARGE SETTLING TANKS WERE CHARGED FROM THIS HOLDING AREA BY A TRAM ON RAILS AND BY A SLUICEWAY SEEN AS THE DARK SPOT ON THE CENTER LEFT EDGE OF THE FRAME. AFTER THE TAILINGS WERE LEACHED, THEY WERE DEPOSITED ON THE LARGE WASTE PILE AT CENTER RIGHT. THE TANK AT CENTER RIGHT EDGE IS WHERE THE WATER PIPELINE ENTERED THE WORKS. A STRAIGHT LINE OF POSTS IN THE GROUND GO ACROSS THE CENTER FROM LEFT TO RIGHT, WHICH ORIGINALLY SUSPENDED THE WATER PIPELINE GOING FROM THE WATER HOLDING TANK AT RIGHT UP TO THE SECONDARY WATER TANKS ABOVE THE MILL. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

  16. Corrosion in prestressed concrete: Pipes, piles, and decks

    SciTech Connect

    Szeliga, M.

    1995-12-31

    This is the first compilation or book focusing on prestressed concrete. It features 21 classic NACE papers on prestressed concrete piping, piles, bridge decks, and cathodic protection. It includes basic corrosion mechanisms of prestressed concrete structures with detailed case histories of corrosion failures and corrective measures.

  17. VIEW OF PROCESS DEVELOPMENT PILE (PDP) TANK, LOOKING WESTSOUTHWEST, BASEMENT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF PROCESS DEVELOPMENT PILE (PDP) TANK, LOOKING WEST-SOUTHWEST, BASEMENT LEVEL -15’. EDGE O FRESONANCE TEST REACTOR (RTR), LATER KNOWN AS LATTICE TEST REACTOR (LTR), VISIBLE TO RIGHT OF PDP TANK - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC

  18. Detail section extending from shore. Note the paired support pilings, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail section extending from shore. Note the paired support pilings, concrete curbs with rectangular openings for drainage, and large-diameter metal pipe suspended under the deck. USS MISSOURI in background - U.S. Naval Base, Pearl Harbor, Gasoline Wharf, Offshore, near the intersection of Hornet Avenue & Curtis Street, Ford Island, Pearl City, Honolulu County, HI

  19. Enhanced In-pile Instrumentation for Material Testing Reactors

    SciTech Connect

    Joy Rempe; Darrell Knudson; Joshua Daw; Troy Unruh; Benjamin Chase; Kurt Davis; Robert Schley

    2012-07-01

    An increasing number of U.S. nuclear research programs are requesting enhanced in-pile instrumentation capable of providing real-time measurements of key parameters during irradiations. For example, fuel research and development funded by the U.S. Department of Energy now emphasize approaches that rely on first principle models to develop optimized fuel designs that offer significant improvements over current fuels. To facilitate this approach, high fidelity, real-time data are essential for characterizing the performance of new fuels during irradiation testing. Furthermore, sensors that obtain such data must be miniature, reliable and able to withstand high flux/high temperature conditions. Depending on user requirements, sensors may need to obtain data in inert gas, pressurized water, or liquid metal environments. To address these user needs, in-pile instrumentation development efforts have been initiated as part of the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF), the Fuel Cycle Research & Development (FCR&D), and the Nuclear Energy Enabling Technology (NEET) programs. This paper reports on recent INL achievements to support these programs. Specifically, an overview of the types of sensors currently available to support in-pile irradiations and those sensors currently available to MTR users are identified. In addition, recent results and products available from sensor research and development are detailed. Specifically, progress in deploying enhanced in-pile sensors for detecting elongation and thermal conductivity are reported. Results from research to evaluate the viability of ultrasonic and fiber optic technologies for irradiation testing are also summarized.

  20. 8. Historic view, Pier 9. Plan of deck and pilings, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Historic view, Pier 9. Plan of deck and pilings, 1932. Photographic copy of original. Boston National Historical Park Archives, Charlestown Navy Yard. - Charlestown Navy Yard, Pier 9, Between Piers 8 & 10, along Mystic River on Charlestown Waterfront at eastern edge of Navy Yard, Boston, Suffolk County, MA

  1. 11. Historic drawing, Pier 10. Plan of deck and pilings, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Historic drawing, Pier 10. Plan of deck and pilings, 1932. Photographic copy of original. Boston National Historical Park Archives, Charlestown Navy Yard. - Charlestown Navy Yard, Pier 10, Between Piers 9 & 11 along Mystic River on Charlestown Waterfront at eastern edge of Charlestown Navy Yard, Boston, Suffolk County, MA

  2. 3. VIEW OF EMPIRE STATE MINE WITH TAILING PILE IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. VIEW OF EMPIRE STATE MINE WITH TAILING PILE IN BOTTOM LEFT AND COLLAPSED ADIT LOCATED BELOW DARK SHADOWS IN FAR RIGHT/LOWER THIRD. COLLAPSED BUILDING AND PARTIAL VIEW OF ORE CHUTE/BIN IS VISIBLE ON HILLSIDE ABOVE TAILINGS. CAMERA POINTED NORTH/NORTHWEST. - Florida Mountain Mining Sites, Empire State Mine, West side of Florida Mountain, Silver City, Owyhee County, ID

  3. 30 CFR 77.215 - Refuse piles; construction requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Refuse piles; construction requirements. 77.215 Section 77.215 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... controlling or extinguishing a fire. (c) Clay or other sealants shall be used to seal the surface of...

  4. 30 CFR 77.215 - Refuse piles; construction requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; construction requirements. 77.215 Section 77.215 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... controlling or extinguishing a fire. (c) Clay or other sealants shall be used to seal the surface of...

  5. 1. GENERAL VIEW FROM BONY PILE LOOKING SOUTH. WASH HOUSE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL VIEW FROM BONY PILE LOOKING SOUTH. WASH HOUSE IN LEFT BACKGROUND. TIPPLE AND CLEANING PLANT TO RIGHT. IN CENTER IS A TANK USED FOR TREATING MINE REFUSE AND ACID RUNOFF. - Eureka No. 40, Tipple & Cleaning Plant, East of State Route 56, north of Little Paint Creek, Scalp Level, Cambria County, PA

  6. Airborne sound propagation over sea during offshore wind farm piling.

    PubMed

    Van Renterghem, T; Botteldooren, D; Dekoninck, L

    2014-02-01

    Offshore piling for wind farm construction has attracted a lot of attention in recent years due to the extremely high noise emission levels associated with such operations. While underwater noise levels were shown to be harmful for the marine biology, the propagation of airborne piling noise over sea has not been studied in detail before. In this study, detailed numerical calculations have been performed with the Green's Function Parabolic Equation (GFPE) method to estimate noise levels up to a distance of 10 km. Measured noise emission levels during piling of pinpiles for a jacket-foundation wind turbine were assessed and used together with combinations of the sea surface state and idealized vertical sound speed profiles (downwind sound propagation). Effective impedances were found and used to represent non-flat sea surfaces at low-wind sea states 2, 3, and 4. Calculations show that scattering by a rough sea surface, which decreases sound pressure levels, exceeds refractive effects, which increase sound pressure levels under downwind conditions. This suggests that the presence of wind, even when blowing downwind to potential receivers, is beneficial to increase the attenuation of piling sound over the sea. A fully flat sea surface therefore represents a worst-case scenario. PMID:25234870

  7. The impact of wind energy turbine piles on ocean dynamics

    NASA Astrophysics Data System (ADS)

    Grashorn, Sebastian; Stanev, Emil V.

    2016-04-01

    The small- and meso-scale ocean response to wind parks has not been investigated in the southern North Sea until now with the help of high-resolution numerical modelling. Obstacles such as e.g. wind turbine piles may influence the ocean current system and produce turbulent kinetic energy which could affect sediment dynamics in the surrounding area. Two setups of the unstructured-grid model SCHISM (Semi-implicit Cross-scale Hydroscience Integrated System Model) have been developed for an idealized channel including a surface piercing cylindrical obstacle representing the pile and a more realistic test case including four exemplary piles. Experiments using a constant flow around the obstacles and a rotating M2 tidal wave are carried out. The resulting current and turbulence patterns are investigated to estimate the influence of the obstacles on the surrounding ocean dynamics. We demonstrate that using an unstructured ocean model provides the opportunity to embed a high-resolution representation of a wind park turbine pile system into a coarser North Sea setup, which is needed in order to perform a seamless investigation of the resulting geophysical processes.

  8. 11. DETAILS: CONCRETE SHEET PILING, CORNERS #4 & #6, DWG. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. DETAILS: CONCRETE SHEET PILING, CORNERS #4 & #6, DWG. NO. 11, 1-1/2" = 1 FT., FEB. 12, 1908, MADE BY E.C.L., APPROVED BY O.F. LACKEY - Baltimore Inner Harbor, Pier 5, South of Pratt Street between Market Place & Concord Street, Baltimore, Independent City, MD

  9. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  10. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  11. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  12. 29 CFR 1926.1439 - Dedicated pile drivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Dedicated pile drivers. 1926.1439 Section 1926.1439 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction §...

  13. 76. VIEW OF PILINGS ON SOUTHEAST SIDE, FACING NORTH AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    76. VIEW OF PILINGS ON SOUTHEAST SIDE, FACING NORTH AND TAKEN FROM THE TACKLE BOX ON THE 3RD TEE, SHOWING REFUGE BAY AND 2ND TEE (RIGHT) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  14. 30 CFR 77.215-2 - Refuse piles; reporting requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; reporting requirements. 77.215-2 Section 77.215-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Surface Installations §...

  15. Risk-Taking Behavior in a Computerized Driving Task: Brain Activation Correlates of Decision-Making, Outcome, and Peer Influence in Male Adolescents

    PubMed Central

    Vorobyev, Victor; Kwon, Myoung Soo; Moe, Dagfinn; Parkkola, Riitta; Hämäläinen, Heikki

    2015-01-01

    Increased propensity for risky behavior in adolescents, particularly in peer groups, is thought to reflect maturational imbalance between reward processing and cognitive control systems that affect decision-making. We used functional magnetic resonance imaging (fMRI) to investigate brain functional correlates of risk-taking behavior and effects of peer influence in 18–19-year-old male adolescents. The subjects were divided into low and high risk-taking groups using either personality tests or risk-taking rates in a simulated driving task. The fMRI data were analyzed for decision-making (whether to take a risk at intersections) and outcome (pass or crash) phases, and for the influence of peer competition. Personality test-based groups showed no difference in the amount of risk-taking (similarly increased during peer competition) and brain activation. When groups were defined by actual task performance, risk-taking activated two areas in the left medial prefrontal cortex (PFC) significantly more in low than in high risk-takers. In the entire sample, risky decision-specific activation was found in the anterior and dorsal cingulate, superior parietal cortex, basal ganglia (including the nucleus accumbens), midbrain, thalamus, and hypothalamus. Peer competition increased outcome-related activation in the right caudate head and cerebellar vermis in the entire sample. Our results suggest that the activation of the medial (rather than lateral) PFC and striatum is most specific to risk-taking behavior of male adolescents in a simulated driving situation, and reflect a stronger conflict and thus increased cognitive effort to take risks in low risk-takers, and reward anticipation for risky decisions, respectively. The activation of the caudate nucleus, particularly for the positive outcome (pass) during peer competition, further suggests enhanced reward processing of risk-taking under peer influence. PMID:26052943

  16. Risk-Taking Behavior in a Computerized Driving Task: Brain Activation Correlates of Decision-Making, Outcome, and Peer Influence in Male Adolescents.

    PubMed

    Vorobyev, Victor; Kwon, Myoung Soo; Moe, Dagfinn; Parkkola, Riitta; Hämäläinen, Heikki

    2015-01-01

    Increased propensity for risky behavior in adolescents, particularly in peer groups, is thought to reflect maturational imbalance between reward processing and cognitive control systems that affect decision-making. We used functional magnetic resonance imaging (fMRI) to investigate brain functional correlates of risk-taking behavior and effects of peer influence in 18-19-year-old male adolescents. The subjects were divided into low and high risk-taking groups using either personality tests or risk-taking rates in a simulated driving task. The fMRI data were analyzed for decision-making (whether to take a risk at intersections) and outcome (pass or crash) phases, and for the influence of peer competition. Personality test-based groups showed no difference in the amount of risk-taking (similarly increased during peer competition) and brain activation. When groups were defined by actual task performance, risk-taking activated two areas in the left medial prefrontal cortex (PFC) significantly more in low than in high risk-takers. In the entire sample, risky decision-specific activation was found in the anterior and dorsal cingulate, superior parietal cortex, basal ganglia (including the nucleus accumbens), midbrain, thalamus, and hypothalamus. Peer competition increased outcome-related activation in the right caudate head and cerebellar vermis in the entire sample. Our results suggest that the activation of the medial (rather than lateral) PFC and striatum is most specific to risk-taking behavior of male adolescents in a simulated driving situation, and reflect a stronger conflict and thus increased cognitive effort to take risks in low risk-takers, and reward anticipation for risky decisions, respectively. The activation of the caudate nucleus, particularly for the positive outcome (pass) during peer competition, further suggests enhanced reward processing of risk-taking under peer influence. PMID:26052943

  17. INCREASED STABLE BETA IN DIII-D BY SUPPRESSION OF A NEOCLASSICAL TEARING MODE USING ELECTRON CYCLOTRON CURRENT DRIVE AND ACTIVE FEEDBACK

    SciTech Connect

    LAHAYE,RJ; HUMPHREYS,DA; LOHR,J; LUCE,TC; PERKINS,FW; PETTY,CC; PRATER,R; STRAIT,EJ

    2002-09-01

    OAK A271 INCREASED STABLE BETA IN DIII-D BY SUPPRESSION OF A NEOCLASSICAL TEARING MODE USING ELECTRON CYCLOTRON CURRENT DRIVE AND ACTIVE FEEDBACK. In DIII-D, the first real-time active control of the electron cyclotron current drive stabilization of a neoclassical tearing mode (here m/n=3/2) is demonstrated. The plasma control system is put into a search and suppress mode to align the ECCD with the island by making either small rigid radial position shifts (of order 1 cm) of the entire plasma (and thus the island) or small changes in toroidal field (of order 0.5%) which radially moves the second harmonic resonance location (and thus the rf current drive). The optimum position minimizes the real-time mode amplitude signal and stabilization occurs despite changes in island location from discharge-to-discharge or from time-to-time. When the neutral beam heating power is programmed to rise after mode suppression by the ECCD, the plasma pressure increases above the peak at the onset of the neoclassical tearing mode until the magnetic island reappears due to the ECCD no longer being on the optimal position. Real-time tracking of the change in location of q=3/2 due to the Shafranov shift with increasing beta is necessary to position the ECCD in the absence of a mode so that higher stable beta can be sustained. The control techniques developed for the m/n=3/2 NTM are also being applied to the more deleterious m/n-2/1 NTM. For the first time in any tokamak, an m/n=2/1 mode has been completely suppressed using radially localized off-axis ECCD.

  18. Behavior of pile group with elevated cap subjected to cyclic lateral loads

    NASA Astrophysics Data System (ADS)

    Chen, Yun-min; Gu, Ming; Chen, Ren-peng; Kong, Ling-gang; Zhang, Zhe-hang; Bian, Xue-cheng

    2015-06-01

    The pile group with elevated cap is widely used as foundation of offshore structures such as turbines, power transmission towers and bridge piers, and understanding its behavior under cyclic lateral loads induced by waves, tide water and winds, is of great importance to designing. A large-scale model test on 3×3 pile group with elevated cap subjected to cyclic lateral loads was performed in saturated silts. The preparation and implementation of the test is presented. Steel pipes with the outer diameter of 114 mm, thickness of 4.5 mm, and length of 6 m were employed as model piles. The pile group was cyclic loaded in a multi-stage sequence with the lateral displacement controlled. In addition, a single pile test was also conducted at the same site for comparison. The displacement of the pile cap, the internal forces of individual piles, and the horizontal stiffness of the pile group are presented and discussed in detail. The results indicate that the lateral cyclic loads have a greater impact on pile group than that on a single pile, and give rise to the significant plastic strain in the soil around piles. The lateral loads carried by each row of piles within the group would be redistributed with loading cycles. The lateral stiffness of the pile group decreases gradually with cycles and broadly presents three different degradation patterns in the test. Significant axial forces were measured out in some piles within the group, owing to the strong restraint provided by the cap, and finally lead to a large settlement of the pile group. These findings can be referred for foundation designing of offshore structures.

  19. The prediction of changes of characteristics of materials and units of the drive mechanism of solar arrays of a spacecraft with the term of active existence of 10 to 15 years

    NASA Astrophysics Data System (ADS)

    Shatikhin, V. Ye.; Pereverziev, Ye. S.; Daniiev, Yu. F.

    We consider changes of characteristics of materials and units of the drive mechanism of solar arrays of spacecraft under the influence of open space factors for the term of active existence of 10 to 15 years. The main open space factors effecting on the characteristics of materials and units of the drive mechanism are listed. The analysis of possible flaws and failures of the drive mechanism is made. We derived the probability of the penetration of meteoric bodies for a drive unit of a solar array during a 10-year and a 15-year flights. We developed some recommendations concerning the elaboration of solar array drive mechanisms for spacecraft with the long term of existence.

  20. Driving on the Descartes

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Astronaut John W. Young, Apollo 16 mission commander, drives the 'Rover', Lunar Roving Vehicle (LRV) to its final parking place near the end of the third extravehicular activity (EVA-3) at the Descartes landing site. Astronaut Charles M. Duke Jr., Lunar Module pilot, took this photograph looking southward. The flank of Stone Mountain can be seen on the horizon at left. The shadow of the Lunar Module 'Orion' is visible in the foreground.

  1. Variable reluctance drive system

    SciTech Connect

    Lipo, T.A.; Liang, F.

    1995-10-17

    A variable reluctance drive system including a motor and corresponding converter for improved current commutation is described. The motor incorporates a salient pole rotor and a salient pole stator having one or more full pitch windings which operate by mutual inductance to transfer the current from the active short pitch winding following phase alignment. This increases output torque and/or speed and permits a number of simple and economical converter circuits. 17 figs.

  2. Supermode noise suppression in an actively mode-locked fiber laser with pulse intensity feed-forward and a dual-drive MZM

    NASA Astrophysics Data System (ADS)

    Xu, Kun; Wang, Ruixin; Dai, Yitang; Yin, Feifei; Li, Jianqiang; Ji, Yuefeng; Lin, Jintong

    2013-05-01

    The supermode noise in an actively mode-locked fiber laser is suppressed for the first time by a so-called pulse-intensity-feed-forward technique. In this novel scheme, the optical pulse is firstly converted into an electronic signal, and then fed forward to a dual-drive Mach-Zehnder modulator (MZM), where the optical pulse is modulated by the reversed intensity profile of itself. In a 12.5 m long actively mode-locked fiber ring laser experiment, the resulting power limiting shows a stable 10 GHz optical pulse train with a supermode-suppression ratio larger than 81 dB. The phase noise and pulse-to-pulse timing jitter are below -141 dBc Hz-1 at 10 MHz and 22.1 fs, respectively. Compared with the conventional fiber-nonlinearity-based power limiting schemes, our proposal is compact and stable.

  3. Postmortem analysis of sand grain crushing from pile interface using X-ray tomography

    NASA Astrophysics Data System (ADS)

    Silva, I. Matías; Combe, Gaël; Foray, Pierre; Flin, Frédéric; Lesaffre, Bernard

    2013-06-01

    Pile foundations of offshore platforms, wind and water turbines are typically subjected to a variety of cyclic loading paths due to their complex environment. While many studies focus on global pile behaviour, the soil-pile interface is explored here by a micromechanical study of the soil layer in contact with the pile surface. This work is devoted to the analysis of frozen post-mortem silica sand samples recovered at the pile interface following installation and cyclic loading tests in a calibration chamber using x-ray tomography. An experimental procedure developed for three dimensional (3D) snow imaging was adapted for the recovery of the in-situ sand samples to preserve their structure during tomography scans. 3D images at a pixel size of 7 μm were then obtained using a cryogenic cell. Results confirm the presence of a shear band at the pile surface as well as void ratios changes in the direction of the pile's radius.

  4. Postmortem analysis of sand grain crushing from pile interface using X-ray tomography

    SciTech Connect

    Silva, I. Matias; Combe, Gaeel; Foray, Pierre; Flin, Frederic; Lesaffre, Bernard

    2013-06-18

    Pile foundations of offshore platforms, wind and water turbines are typically subjected to a variety of cyclic loading paths due to their complex environment. While many studies focus on global pile behaviour, the soil-pile interface is explored here by a micromechanical study of the soil layer in contact with the pile surface. This work is devoted to the analysis of frozen post-mortem silica sand samples recovered at the pile interface following installation and cyclic loading tests in a calibration chamber using x-ray tomography. An experimental procedure developed for three dimensional (3D) snow imaging was adapted for the recovery of the in-situ sand samples to preserve their structure during tomography scans. 3D images at a pixel size of 7 {mu}m were then obtained using a cryogenic cell. Results confirm the presence of a shear band at the pile surface as well as void ratios changes in the direction of the pile's radius.

  5. Simulations of dislocation pile-ups at assymetric tilt boundaries in aluminum

    SciTech Connect

    Valone, Steven; Wang, Jian M; Hoagland, Richard C; Germann, Timothy C

    2011-01-21

    Materials deformation processes are increasingly approachable through the both conventional and accelerated molecular dynamics. In one deformation process, dislocation pile-up at a grain boundary, a greater understanding is required as to how dislocations transmit through grain boundaries, causing plastic deformation, or reflect and reconstruct the grain boundary, but with no macroscopic deformation. Here dislocation pile-ups in an alwninum bicrystal with an asymmetric tilt grain boundary are simulated atomistically, introducing effects of dislocation interactions beyond linear elastic ones. The observed responses as functions of the number of explicitly modeled dislocations and the magnitude of the applied stress are discussed. Typical conditions for the simulations consist of thermal relaxation room temperature, five active dislocations inserted within a 6.5-million-atom cell, and an additional fourteen dislocations represented within the atomistic simulation by their elastic strain fields. The dislocations are initially distributed according to linear elastic estimates of their positions in a double-ended pile-up from a chosen far-field stress. The whole cell is allowed to relax according to a procedure to be described. In the ensuing simulations, the system is propagated for some substantial period of time (lOs of ps), followed by small increments of strain. After a number of such increments, we observe all of the anticipated events. Usually several of the closest dislocations are absorbed into the grain boundary, resulting in varying amounts of reconstruction. Reflections from the boundary are common and show a strong dependence on sample thickness. Transmission events are seen on both slip systems in the other grain. The particulars of these events will be described as well.

  6. A Postsynaptic AMPK→p21-Activated Kinase Pathway Drives Fasting-Induced Synaptic Plasticity in AgRP Neurons.

    PubMed

    Kong, Dong; Dagon, Yossi; Campbell, John N; Guo, Yikun; Yang, Zongfang; Yi, Xinchi; Aryal, Pratik; Wellenstein, Kerry; Kahn, Barbara B; Sabatini, Bernardo L; Lowell, Bradford B

    2016-07-01

    AMP-activated protein kinase (AMPK) plays an important role in regulating food intake. The downstream AMPK substrates and neurobiological mechanisms responsible for this, however, are ill defined. Agouti-related peptide (AgRP)-expressing neurons in the arcuate nucleus regulate hunger. Their firing increases with fasting, and once engaged they cause feeding. AgRP neuron activity is regulated by state-dependent synaptic plasticity: fasting increases dendritic spines and excitatory synaptic activity; feeding does the opposite. The signaling mechanisms underlying this, however, are also unknown. Using neuron-specific approaches to measure and manipulate kinase activity specifically within AgRP neurons, we establish that fasting increases AMPK activity in AgRP neurons, that increased AMPK activity in AgRP neurons is both necessary and sufficient for fasting-induced spinogenesis and excitatory synaptic activity, and that the AMPK phosphorylation target mediating this plasticity is p21-activated kinase. This provides a signaling and neurobiological basis for both AMPK regulation of energy balance and AgRP neuron state-dependent plasticity. PMID:27321921

  7. [Driving and health at work].

    PubMed

    Giorgio, Marie-Thérèse

    2015-09-01

    The role of the occupational physician is to prevent occupational accidents and diseases. Therefore, he is the one to decide if a worker is fit to drive in the context of his professional activity, including in cases where no specific driving license is required (e.g. forklift truck, mobile crane). This decision is an important one, as two thirds of fatal occupational accidents occur on the road. The decision is made on the basis of both a medical examination and the regulation, which indicates all contraindications to driving. The physician's responsibility is involved, as is the employer's, as he must ensure that his employee is fit to drive and possesses a valid driving license at all times. PMID:25960440

  8. Picking up Clues from the Discard Pile (Stereo)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    As NASA's Phoenix Mars Lander excavates trenches, it also builds piles with most of the material scooped from the holes. The piles, like this one called 'Caterpillar,' provide researchers some information about the soil.

    On Aug. 24, 2008, during the late afternoon of the 88th Martian day after landing, Phoenix's Surface Stereo Imager took separate exposures through its left eye and right eye that have been combined into this stereo view. The image appears three dimensional when seen through red-blue glasses.

    This conical pile of soil is about 10 centimeters (4 inches) tall. The sources of material that the robotic arm has dropped onto the Caterpillar pile have included the 'Dodo' and ''Upper Cupboard' trenches and, more recently, the deeper 'Stone Soup' trench.

    Observations of the pile provide information, such as the slope of the cone and the textures of the soil, that helps scientists understand properties of material excavated from the trenches.

    For the Stone Soup trench in particular, which is about 18 centimeters (7 inches) deep, the bottom of the trench is in shadow and more difficult to observe than other trenches that Phoenix has dug. The Phoenix team obtained spectral clues about the composition of material from the bottom of Stone Soup by photographing Caterpillar through 15 different filters of the Surface Stereo Imager when the pile was covered in freshly excavated material from the trench.

    The spectral observation did not produce any sign of water-ice, just typical soil for the site. However, the bigger clumps do show a platy texture that could be consistent with elevated concentration of salts in the soil from deep in Stone Soup. The team chose that location as the source for a soil sample to be analyzed in the lander's wet chemistry laboratory, which can identify soluble salts in the soil.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA

  9. Impact simulations on the rubble pile asteroid (2867) Steins

    NASA Astrophysics Data System (ADS)

    Deller, Jakob; Lowry, Stephen; Snodgrass, Colin; Price, Mark; Sierks, Holger

    2015-04-01

    Images from the OSIRIS camera system on board the Rosetta spacecraft (Keller et al. 2010) have revealed several interesting features on asteroid (2867) Steins. Its macro porosity of 40%, together with the shape that looks remarkably like a YORP evolved body, both indicate a rubble pile structure. A large crater on the southern pole is evidence for collisional evolution of this rubble pile asteroid. We have developed a new approach for simulating impacts on asteroid bodies that connects formation history to their collisional evolution. This is achieved by representing the interior as a 'rubble pile', created from the gravitational aggregation of spherical 'pebbles' that represent fragments from a major disruption event. These 'pebbles' follow a power-law size function and constitute the building blocks of the rubble pile. This allows us to explicitly model the interior of rubble pile asteroids in hyper-velocity impact simulations in a more realistic way. We present preliminary results of a study validating our approach in a large series of simulated impacts on a typical small main-belt rubble pile asteroid using the Smoothed Particle Hydrodynamics solver in LS-DYNA. We show that this approach allows us to explicitly follow the behavior of a single 'pebble', while preserving the expected properties of the bulk asteroid as known from observations and experiments (Holsapple 2009). On the example of Steins, we use this model to relate surface features like the northern hill at 75/100 degrees lon/lat distance to the largest crater (Jorda et al. 2012), or the catena of depletion pits, to the displacement of large fragments in the interior of the asteroid during the impact. We do this by following the movement of pebbles below the surface feature in simulations that recreate the shape of the impact crater. We show that while it is not straightforward to explain the formation of the hill-like structure, the formation of cracks possibly leading to depletion zones can be

  10. The supercritical pile gamma-ray burst model: The GRB afterglow steep decline and plateau phase

    SciTech Connect

    Sultana, J.; Kazanas, D.

    2013-12-10

    We present a process that accounts for the steep decline and plateau phase of the Swift X-Ray Telescope (XRT) light curves, vexing features of gamma-ray burst (GRB) phenomenology. This process is an integral part of the 'supercritical pile' GRB model, proposed a few years ago to account for the conversion of the GRB kinetic energy into radiation with a spectral peak at E {sub pk} ∼ m{sub e}c {sup 2}. We compute the evolution of the relativistic blast wave (RBW) Lorentz factor Γ to show that the radiation-reaction force due to the GRB emission can produce an abrupt, small (∼25%) decrease in Γ at a radius that is smaller (depending on conditions) than the deceleration radius R{sub D} . Because of this reduction, the kinematic criticality criterion of the 'supercritical pile' is no longer fulfilled. Transfer of the proton energy into electrons ceases and the GRB enters abruptly the afterglow phase at a luminosity smaller by ∼m{sub p} /m{sub e} than that of the prompt emission. If the radius at which this slow-down occurs is significantly smaller than R{sub D} , the RBW internal energy continues to drive the RBW expansion at a constant (new) Γ and its X-ray luminosity remains constant until R{sub D} is reached, at which point it resumes its more conventional decay, thereby completing the 'unexpected' XRT light curve phase. If this transition occurs at R ≅ R{sub D} , the steep decline is followed by a flux decrease instead of a 'plateau,' consistent with the conventional afterglow declines. Besides providing an account of these peculiarities, the model suggests that the afterglow phase may in fact begin before the RBW reaches R ≅ R{sub D} , thus providing novel insights into GRB phenomenology.

  11. The Supercritical Pile Gamma-Ray Burst Model: The GRB Afterglow Steep Decline and Plateau Phase

    NASA Astrophysics Data System (ADS)

    Sultana, J.; Kazanas, D.; Mastichiadis, A.

    2013-12-01

    We present a process that accounts for the steep decline and plateau phase of the Swift X-Ray Telescope (XRT) light curves, vexing features of gamma-ray burst (GRB) phenomenology. This process is an integral part of the "supercritical pile" GRB model, proposed a few years ago to account for the conversion of the GRB kinetic energy into radiation with a spectral peak at E pk ~ mec 2. We compute the evolution of the relativistic blast wave (RBW) Lorentz factor Γ to show that the radiation-reaction force due to the GRB emission can produce an abrupt, small (~25%) decrease in Γ at a radius that is smaller (depending on conditions) than the deceleration radius RD . Because of this reduction, the kinematic criticality criterion of the "supercritical pile" is no longer fulfilled. Transfer of the proton energy into electrons ceases and the GRB enters abruptly the afterglow phase at a luminosity smaller by ~mp /me than that of the prompt emission. If the radius at which this slow-down occurs is significantly smaller than RD , the RBW internal energy continues to drive the RBW expansion at a constant (new) Γ and its X-ray luminosity remains constant until RD is reached, at which point it resumes its more conventional decay, thereby completing the "unexpected" XRT light curve phase. If this transition occurs at R ~= RD , the steep decline is followed by a flux decrease instead of a "plateau," consistent with the conventional afterglow declines. Besides providing an account of these peculiarities, the model suggests that the afterglow phase may in fact begin before the RBW reaches R ~= RD , thus providing novel insights into GRB phenomenology.

  12. The Supercritical Pile Gamma-Ray Burst Model: The GRB Afterglow Steep Decline and Plateau Phase

    NASA Technical Reports Server (NTRS)

    Sultana, Joseph; Kazanas, D.; Mastichiadis, A.

    2013-01-01

    We present a process that accounts for the steep decline and plateau phase of the Swift X-Ray Telescope (XRT) light curves, vexing features of gamma-ray burst (GRB) phenomenology. This process is an integral part of the "supercritical pile" GRB model, proposed a few years ago to account for the conversion of the GRB kinetic energy into radiation with a spectral peak at E(sub pk) is approx. m(sub e)C(exp 2). We compute the evolution of the relativistic blast wave (RBW) Lorentz factor Gamma to show that the radiation-reaction force due to the GRB emission can produce an abrupt, small (approx. 25%) decrease in Gamma at a radius that is smaller (depending on conditions) than the deceleration radius R(sub D). Because of this reduction, the kinematic criticality criterion of the "supercritical pile" is no longer fulfilled. Transfer of the proton energy into electrons ceases and the GRB enters abruptly the afterglow phase at a luminosity smaller by approx. m(sub p)/m(sub e) than that of the prompt emission. If the radius at which this slow-down occurs is significantly smaller than R(sub D), the RBW internal energy continues to drive the RBW expansion at a constant (new) Gamma and its X-ray luminosity remains constant until R(sub D) is reached, at which point it resumes its more conventional decay, thereby completing the "unexpected" XRT light curve phase. If this transition occurs at R is approx. equal to R(sub D), the steep decline is followed by a flux decrease instead of a "plateau," consistent with the conventional afterglow declines. Besides providing an account of these peculiarities, the model suggests that the afterglow phase may in fact begin before the RBW reaches R is approx. equal to R(sub D), thus providing novel insights into GRB phenomenology.

  13. A spectrum of CodY activities drives metabolic reorganization and virulence gene expression in Staphylococcus aureus.

    PubMed

    Waters, Nicholas R; Samuels, David J; Behera, Ranjan K; Livny, Jonathan; Rhee, Kyu Y; Sadykov, Marat R; Brinsmade, Shaun R

    2016-08-01

    The global regulator CodY controls the expression of dozens of metabolism and virulence genes in the opportunistic pathogen Staphylococcus aureus in response to the availability of isoleucine, leucine and valine (ILV), and GTP. Using RNA-Seq transcriptional profiling and partial activity variants, we reveal that S. aureus CodY activity grades metabolic and virulence gene expression as a function of ILV availability, mediating metabolic reorganization and controlling virulence factor production in vitro. Strains lacking CodY regulatory activity produce a PIA-dependent biofilm, but development is restricted under conditions that confer partial CodY activity. CodY regulates the expression of thermonuclease (nuc) via the Sae two-component system, revealing cascading virulence regulation and factor production as CodY activity is reduced. Proteins that mediate the host-pathogen interaction and subvert the immune response are shut off at intermediate levels of CodY activity, while genes coding for enzymes and proteins that extract nutrients from tissue, that kill host cells, and that synthesize amino acids are among the last genes to be derepressed. We conclude that S. aureus uses CodY to limit host damage to only the most severe starvation conditions, providing insight into one potential mechanism by which S. aureus transitions from a commensal bacterium to an invasive pathogen. PMID:27116338

  14. Inactivity-induced respiratory plasticity: protecting the drive to breathe in disorders that reduce respiratory neural activity.

    PubMed

    Strey, K A; Baertsch, N A; Baker-Herman, T L

    2013-11-01

    Multiple forms of plasticity are activated following reduced respiratory neural activity. For example, in ventilated rats, a central neural apnea elicits a rebound increase in phrenic and hypoglossal burst amplitude upon resumption of respiratory neural activity, forms of plasticity called inactivity-induced phrenic and hypoglossal motor facilitation (iPMF and iHMF), respectively. Here, we provide a conceptual framework for plasticity following reduced respiratory neural activity to guide future investigations. We review mechanisms giving rise to iPMF and iHMF, present new data suggesting that inactivity-induced plasticity is observed in inspiratory intercostals (iIMF) and point out gaps in our knowledge. We then survey conditions relevant to human health characterized by reduced respiratory neural activity and discuss evidence that inactivity-induced plasticity is elicited during these conditions. Understanding the physiological impact and circumstances in which inactivity-induced respiratory plasticity is elicited may yield novel insights into the treatment of disorders characterized by reductions in respiratory neural activity. PMID:23816599

  15. mTOR drives its own activation via SCFβ-TRCP-dependent degradation of the mTOR inhibitor DEPTOR

    PubMed Central

    Gao, Daming; Inuzuka, Hiroyuki; Tan, Meng-Kwang Marcus; Fukushima, Hidefumi; Locasale, Jason W.; Liu, Pengda; Wan, Lixin; Zhai, Bo; Chin, Y. Rebecca; Shaik, Shavali; Lyssiotis, Costas A.; Gygi, Steven P.; Toker, Alex; Cantley, Lewis C.; Asara, John M.; Harper, J. Wade; Wei, Wenyi

    2011-01-01

    Summary The activities of both mTORC1 and mTORC2 are negatively regulated by their endogenous inhibitor, DEPTOR. As such, the abundance of DEPTOR is a critical determinant in the activity status of the mTOR network. DEPTOR stability is governed by the 26S-proteasome through a largely unknown mechanism. Here we describe an mTOR-dependent phosphorylation-driven pathway for DEPTOR destruction via SCFβ-TRCP. DEPTOR phosphorylation by mTOR in response to growth signals, and in collaboration with casein kinase I (CKI), generates a phosphodegron that binds β-TRCP. Failure to degrade DEPTOR through either degron mutation or β-TRCP depletion leads to reduced mTOR activity, reduced S6 kinase activity, and activation of autophagy to reduce cell growth. This work expands the current understanding of mTOR regulation by revealing a positive feedback loop involving mTOR and CKI-dependent turnover of its inhibitor, DEPTOR, suggesting that misregulation of the DEPTOR destruction pathway might contribute to aberrant activation of mTOR in disease. PMID:22017875

  16. Driving electrocatalytic activity by interface electronic structure control in a metalloprotein hybrid catalyst for efficient hydrogen evolution.

    PubMed

    Behera, Sushant Kumar; Deb, Pritam; Ghosh, Arghya

    2016-08-17

    The rational design of metalloprotein hybrid structures and precise calculations for understanding the role of the interfacial electronic structure in regulating the HER activity of water splitting sites and their microscopic effect for obtaining robust hydrogen evolution possess great promise for developing highly efficient nano-bio hybrid HER catalysts. Here, we employ high-accuracy linear-scaling density functional theory calculations using a near-complete basis set and a minimal parameter implicit solvent model within the self-consistent calculations, on silver (Ag) ions assimilated on bacteriorhodopsin (bR) at specific binding sites. Geometry optimization indicates the formation of active sites at the interface of the metalloprotein complex and the density of states reflects the metallic nature of the active sites. The reduced value of the canonical orbital gap indicates the state of dynamic nature after Ag ion assimilation on active sites and smooth electron transfer. These incorporated active protein sites are more efficient in electrolytic splitting of water than pristine sites due to their low value of Gibbs free energy for the HER in terms of hydrogen coverages. Volcano plot analysis and the free energy diagram are compared for understanding the hydrogen evolution efficiency. Moreover, the essential role of the interfacial electronic properties in regulating the HER catalytic activity of water splitting sites and enhancing the efficiency is elucidated. PMID:27499158

  17. PINK1 drives Parkin self-association and HECT-like E3 activity upstream of mitochondrial binding

    PubMed Central

    Lazarou, Michael; Narendra, Derek P.; Jin, Seok Min; Tekle, Ephrem; Banerjee, Soojay

    2013-01-01

    Genetic studies indicate that the mitochondrial kinase PINK1 and the RING-between-RING E3 ubiquitin ligase Parkin function in the same pathway. In concurrence, mechanistic studies show that PINK1 can recruit Parkin from the cytosol to the mitochondria, increase the ubiquitination activity of Parkin, and induce Parkin-mediated mitophagy. Here, we used a cell-free assay to recapitulate PINK1-dependent activation of Parkin ubiquitination of a validated mitochondrial substrate, mitofusin 1. We show that PINK1 activated the formation of a Parkin–ubiquitin thioester intermediate, a hallmark of HECT E3 ligases, both in vitro and in vivo. Parkin HECT-like ubiquitin ligase activity was essential for PINK1-mediated Parkin translocation to mitochondria and mitophagy. Using an inactive Parkin mutant, we found that PINK1 stimulated Parkin self-association and complex formation upstream of mitochondrial translocation. Self-association occurred independent of ubiquitination activity through the RING-between-RING domain, providing mechanistic insight into how PINK1 activates Parkin. PMID:23319602

  18. PINK1 drives Parkin self-association and HECT-like E3 activity upstream of mitochondrial binding.

    PubMed

    Lazarou, Michael; Narendra, Derek P; Jin, Seok Min; Tekle, Ephrem; Banerjee, Soojay; Youle, Richard J

    2013-01-21

    Genetic studies indicate that the mitochondrial kinase PINK1 and the RING-between-RING E3 ubiquitin ligase Parkin function in the same pathway. In concurrence, mechanistic studies show that PINK1 can recruit Parkin from the cytosol to the mitochondria, increase the ubiquitination activity of Parkin, and induce Parkin-mediated mitophagy. Here, we used a cell-free assay to recapitulate PINK1-dependent activation of Parkin ubiquitination of a validated mitochondrial substrate, mitofusin 1. We show that PINK1 activated the formation of a Parkin-ubiquitin thioester intermediate, a hallmark of HECT E3 ligases, both in vitro and in vivo. Parkin HECT-like ubiquitin ligase activity was essential for PINK1-mediated Parkin translocation to mitochondria and mitophagy. Using an inactive Parkin mutant, we found that PINK1 stimulated Parkin self-association and complex formation upstream of mitochondrial translocation. Self-association occurred independent of ubiquitination activity through the RING-between-RING domain, providing mechanistic insight into how PINK1 activates Parkin. PMID:23319602

  19. A Geophysical Laboratory for Rubble Pile Asteroids: The BASiX Mission

    NASA Astrophysics Data System (ADS)

    Scheeres, Daniel J.; Chesley, Steven; Anderson, Robert C.

    2014-11-01

    Small rubble pile asteroids exhibit a diverse range of evolutionary behaviors and morphologies, driven by an array of poorly understood geophysical effects. The complex ways that these bodies evolve belies their simple structure: gravitational aggregates of shattered primitive bodies. Their evolution can be dramatic, such as seen in the active asteroids P/2013 P5 and P/2013 R3, or may be subtly masked, such as in the tide-BYORP equilibria of singly-synchronous binary asteroids. Their evolutionary outcomes can defy the imagination, such as asteroid 1950 DA which is spinning faster than its gravitational attraction yet is held together by weak van der Waals forces (Rozitis et al. 2014), or present us with profound mysteries, such as how the Almahata Sitta meteorite could be comprised of such diverse components. Beyond these motivations, the study of rubble pile asteroid geophysics can shed insight into any solar system environment where gravitational aggregates interact in a micro-gravity setting, ranging from the protoplanetary disc to planetary ring systems. The broad study of the geophysics of aggregates in such micro-gravity environments is becoming both a unifying theme and emerging field of study. Out of the many diverse and complex forms that rubble pile asteroids take on, the study of NEA binary asteroids can in particular be used to expose the geophysics of micro-gravity aggregates. Binaries are an expression of micro-gravity geophysics due to the manner in which they form and their continuing evolution. Due to our ability to visit, probe and interact with NEA, we can also turn them into geophysical laboratories. This talk will introduce the science of the Binary Asteroid in-situ Explorer (BASiX) Discovery mission, which proposes to turn the primitive C-Type binary asteroid (175706) 1996 FG3 into such a geophysical laboratory. Exploring this body enables us to probe a broad range of rubble pile asteroid properties: internal tidal dissipation (through FG3

  20. The Supercritical Pile Model: Prompt Emission Across the Electromagnetic Spectrum

    NASA Technical Reports Server (NTRS)

    Kazanas, Demos; Mastichiadis, A.

    2008-01-01

    The "Supercritical Pile" GRB model is an economical model that provides the dissipation necessary to convert explosively the energy stored in relativistic protons in the blast wave of a GRB into radiation; at the same time it produces spectra whose luminosity peaks at 1 MeV in the lab frame, the result of the kinematics of the proton-photon - pair production reaction that effects the conversion of proton energy to radiation. We outline the fundamental notions behind the "Supercritical Pile" model and discuss the resulting spectra of the prompt emission from optical to gamma-ray energies of order Gamma^2 m_ec^2, (Gamma is the Lorentz factor of the blast wave) present even in the absence of an accelerated particle distribution and compare our results to bursts that cover this entire energy range. Particular emphasis is given on the emission at the GLAST energy range both in the prompt and the afterglow stages of the burst.

  1. The extracellular matrix microtopography drives critical changes in cellular motility and Rho A activity in colon cancer cells

    PubMed Central

    2010-01-01

    We have shown that the microtopography (mT) underlying colon cancer changes as a tumor de-differentiates. We distinguish the well-differentiated mT based on the increasing number of "pits" and poorly differentiated mT on the basis of increasing number of "posts." We investigated Rho A as a mechanosensing protein using mT features derived from those observed in the ECM of colon cancer. We evaluated Rho A activity in less-tumorogenic (Caco-2 E) and more tumorigenic (SW620) colon cancer cell-lines on microfabricated pits and posts at 2.5 μm diameter and 200 nm depth/height. In Caco-2 E cells, we observed a decrease in Rho A activity as well as in the ratio of G/F actin on surfaces with either pits or posts but despite this low activity, knockdown of Rho A led to a significant decrease in confined motility suggesting that while Rho A activity is reduced on these surfaces it still plays an important role in controlling cellular response to barriers. In SW620 cells, we observed that Rho A activity was greatest in cells plated on a post microtopography which led to increased cell motility, and an increase in actin cytoskeletal turnover. PMID:20667086

  2. Pile response to lateral spread: A benchmark case

    SciTech Connect

    Chaudhuri, D.; Toprak, S.; O`Rourke, T.D.

    1995-12-31

    The paper compares analytical results with field observations of piles damaged during the 1964 Niigata earthquake. Three different models for liquefied soil-structure interaction are used, including two subgrade reaction models with both drained and undrained strength parameters and a model to account for the viscosity of liquefied soil. The subgrade reaction model provides for the bet agreement between analytical and observed behavior. Recommendations are made for selecting the most appropriate drained and undrained parameters for analysis and design.

  3. Vegetative cover grows directly on acidic mine refuse pile

    SciTech Connect

    Nickeson, F.H.

    1984-02-01

    The paper reports how permanent, self-sustaining vegetation has been established on an acidic, 80-year old coal refuse pile without using a soil cover. Tests were carried out on a number of 1-acre plots which were treated with different mixtures of lime, fertiliser and seeds of grasses and legumes. The results of the tests are discussed and the way in which the final treatment was chosen is explained. The work is considered to have been successful.

  4. Chibby drives β catenin cytoplasmic accumulation leading to activation of the unfolded protein response in BCR-ABL1+ cells.

    PubMed

    Mancini, Manuela; Leo, Elisa; Takemaru, Ken-Ichi; Campi, Virginia; Borsi, Enrica; Castagnetti, Fausto; Gugliotta, Gabriele; Santucci, Maria Alessandra; Martinelli, Giovanni

    2013-09-01

    Chronic myeloid leukemia (CML) is a myeloproliferative disease caused by the constitutive tyrosine kinase (TK) activity of the BCR-ABL fusion protein. However, the phenotype of leukemic stem cells (LSC) is sustained by β catenin rather than by the BCR-ABL TK. β catenin activity in CML is contingent upon its stabilization proceeding from the BCR-ABL-induced phosphorylation at critical residues for interaction with the Adenomatous polyposis coli (APC)/Axin/glycogen synthase kinase 3 (GSK3) destruction complex or GSK3 inactivating mutations. Here we studied the impact of β catenin antagonist Chibby (CBY) on β catenin signaling in BCR-ABL1+ cells. CBY is a small conserved protein which interacts with β catenin and impairs β catenin-mediated transcriptional activation through two distinct molecular mechanisms: 1) competition with T cell factor (TCF) or lymphoid enhancer factor (LEF) for β catenin binding; and 2) nuclear export of β catenin via interaction with 14-3-3. We found that its enforced expression in K562 cell line promoted β catenin cytoplasmic translocation resulting in inhibition of target gene transcription. Moreover, cytoplasmic accumulation of β catenin activated the endoplasmic reticulum (ER) stress-associated pathway known as unfolded protein response (UPR). CBY-driven cytoplasmic accumulation of β catenin is also a component of BCR-ABL1+ cell response to the TK inhibitor Imatinib (IM). It evoked the UPR activation leading to the induction of BCL2-interacting mediator of cell death (BIM) by UPR sensors. BIM, in turn, contributed to the execution phase of apoptosis in the activation of ER resident caspase 12 and mobilization of Ca(2+) stores. PMID:23707389

  5. Enhanced In-Pile Instrumentation at the Advanced Test Reactor

    SciTech Connect

    Joy Rempe; Darrell Knudson; Joshua Daw; Troy Unruh; Benjamin Chase; Kurt Davis; Robert Schley; Steven Taylor

    2012-08-01

    Many of the sensors deployed at materials and test reactors cannot withstand the high flux/high temperature test conditions often requested by users at U.S. test reactors, such as the Advanced Test Reactor (ATR) at the Idaho National Laboratory. To address this issue, an instrumentation development effort was initiated as part of the ATR National Scientific User Facility in 2007 to support the development and deployment of enhanced in-pile sensors. This paper provides an update on this effort. Specifically, this paper identifies the types of sensors currently available to support in-pile irradiations and those sensors currently available to ATR users. Accomplishments from new sensor technology deployment efforts are highlighted by describing new temperature and thermal conductivity sensors now available to ATR users. Efforts to deploy enhanced in-pile sensors for detecting elongation and real-time flux detectors are also reported, and recently-initiated research to evaluate the viability of advanced technologies to provide enhanced accuracy for measuring key parameters during irradiation testing are noted.

  6. Enhanced In-Pile Instrumentation at the Advanced Test Reactor

    SciTech Connect

    J. Rempe; D. Knudson; J. Daw; T. Unruh; B. Chase; K. Condie

    2011-06-01

    Many of the sensors deployed at materials and test reactors cannot withstand the high flux/high temperature test conditions often requested by users at U.S. test reactors, such as the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). To address this issue, an instrumentation development effort was initiated as part of the ATR National Scientific User Facility (NSUF) in 2007 to support the development and deployment of enhanced in-pile sensors. This paper reports results from this effort. Specifically, this paper identifies the types of sensors currently available to support in-pile irradiations and those sensors currently available to ATR users. Accomplishments from new sensor technology deployment efforts are highlighted by describing new temperature and thermal conductivity sensors now available to ATR users. Efforts to deploy enhanced in-pile sensors for detecting elongation and real-time flux detectors are also reported, and recently-initiated research to evaluate the viability of advanced technologies to provide enhanced accuracy for measuring key parameters during irradiation testing are noted.

  7. The infrabuccal pellet piles of fungus-growing ants.

    PubMed

    Little, Ainslie E F; Murakami, Takahiro; Mueller, Ulrich G; Currie, Cameron R

    2003-12-01

    Fungus-growing ants (Attini) live in an obligate mutualism with the fungi they cultivate for food. Because of the obligate nature of this relationship, the success of the ants is directly dependent on their ability to grow healthy fungus gardens. Attine ants have evolved complex disease management strategies to reduce their garden's exposure to potential parasitic microbes, to prevent the establishment of infection in their gardens, and to remove infected garden sections. The infrabuccal pocket, a filtering device located in the oral cavity of all ants, is an integral part of the mechanisms that leaf-cutter ants use to prevent the invasion and spread of general microbial parasites and the specific fungal-garden parasite Escovopsis. Fungus-growing ants carefully groom their garden, collecting general debris and pathogenic spores of Escovopsis in their infrabuccal pocket, the contents of which are later expelled in dump chambers inside the nest or externally. In this study we examined how a phylogenetically diverse collection of attine ants treat their infrabuccal pellets. Unlike leaf-cutters that deposit their infrabuccal pellets directly in refuse piles, ants of the more basal attine lineages stack their infrabuccal pellets in piles located close to their gardens, and a separate caste of workers is devoted to the construction, management, and eventual disposal of these piles. PMID:14676952

  8. NEET In-Pile Ultrasonic Sensor Enablement-Final Report

    SciTech Connect

    J. Daw; J. Rempe; J. Palmer; P. Ramuhalli; R. Montgomery; H.T. Chien; B. Tittmann; B. Reinhardt; P. Keller

    2014-09-01

    Ultrasonic technologies offer the potential to measure a range of parameters during irradiation of fuels and materials, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes under harsh irradiation test conditions. There are two primary issues that currently limit in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. The harsh nature of in-pile testing and the variety of desired measurements demand that an enhanced signal processing capability be developed to make in-pile ultrasonic sensors viable. To address these issues, the NEET ASI program funded a three year Ultrasonic Transducer Irradiation and Signal Processing Enhancements project, which is a collaborative effort between the Idaho National Laboratory, the Pacific Northwest National Laboratory, the Argonne National Laboratory, and the Pennsylvania State University. The objective of this report is to document the objectives and accomplishments from this three year project. As summarized within this document, significant work has been accomplished during this three year project.

  9. Structural Failure Condition for Bifurcated Rubble Pile Asteroids

    NASA Astrophysics Data System (ADS)

    Hirabayashi, M.; Scheeres, D. J.

    2014-12-01

    The present study investigates the structural failure conditions of uniformly rotating bifurcated asteroids with cohesion due to a static spin-up. We apply a newly derived technique (Hirabayashi and Scheeres, submitted) that probes the failure state of an asteroid. The technique determines an upper bound condition for structural failure of a slice normal to the minimum moment of inertia axis. The detailed study of these failure modes for cohesive, rotating rubble pile asteroid is motivated by recent observations of 'active asteroids,' bodies which are seemingly disintegrating and fissioning due to their rapid spin rates (Jewitt et al. 2013, 2014; Hirabayashi et al. 2014). Figure 1 shows the shape of 4486 Mithra. We compare 3 slices, slices 1 and 3 including the knobs and slice 2 being the neck (Fig. 1), to determine a more precise condition for structural failure. Figures 2 and 3 describe the limit of friction angle with cohesion of 0 Pa and 500 Pa, respectively. The narrow solid, dashed, and dotted lines give the limits of slices 1, 2, and 3, respectively. The bold solid lines indicate the limit of the total volume, i.e., the whole volume reaching the failure point, and that of the partial volume, i.e., the most sensitive condition among the slices. The shadowed areas show the structurally stable regions. The results show that Mithra's failure locations change as a function of its spin periods and cohesion. For the cohesionless case, the knobs are more sensitive to structural failure than the neck at a spin period ranging from 3.8 hr to 4.8 hr, while the neck fails first at other spin periods. For the 500 Pa cohesion case, the limits of friction angle shift to higher spin periods. Also, at higher spin periods, we find that a lower friction angle is sometimes stronger than a higher friction angle. This comes from the fact that under constant cohesion a lower friction angle can give wider stable regions below the yield envelope. Our study reveals that there exits a

  10. N-Formyl peptides drive mitochondrial damage associated molecular pattern induced neutrophil activation through ERK1/2 and P38 MAP kinase signalling pathways.

    PubMed

    Hazeldine, Jon; Hampson, Peter; Opoku, Francis Adusei; Foster, Mark; Lord, Janet M

    2015-01-01

    Traumatic injury results in a systemic inflammatory response syndrome (SIRS), a phenomenon characterised by the release of pro-inflammatory cytokines into the circulation and immune cell activation. Released from necrotic cells as a result of tissue damage, damage associated molecular patterns (DAMPs) are thought to initiate the SIRS response by activating circulating immune cells through surface expressed pathogen recognition receptors. Neutrophils, the most abundant leucocyte in human circulation, are heavily implicated in the initial immune response to traumatic injury and have been shown to elicit a robust functional response to DAMP stimulation. Here, we confirm that mitochondrial DAMPs (mtDAMPs) are potent activators of human neutrophils and show for the first time that signalling through the mitogen-activated-protein-kinases p38 and extracellular-signal-related-kinase 1/2 (ERK1/2) is essential for this response. At 40 and/or 100 μg/ml, mtDAMPs activated human neutrophils, indicated by a significant reduction in the surface expression of L-selectin, and triggered a number of functional responses from both resting and tumour necrosis factor-α primed neutrophils, which included reactive oxygen species (ROS) generation, degranulation, secretion of interleukin-8 and activation of p38 and ERK1/2 MAPKs. Pre-treatment of neutrophils with Cyclosporin H, a selective inhibitor of formyl peptide receptor-1 (FPR-1), significantly inhibited mtDAMP-induced L-selectin shedding as well as p38 and ERK1/2 activation, suggesting that N-formyl peptides are the main constituents driving mtDAMP-induced neutrophil activation. Indeed, no evidence of L-selectin shedding or p38 and ERK1/2 activation was observed in neutrophils challenged with mitochondrial DNA alone. Interestingly, pharmacological inhibition of p38 or ERK1/2 either alone or in combination significantly inhibited L-selectin shedding and IL-8 secretion by mtDAMP-challenged neutrophils, revealing for the first time

  11. Baf60c drives glycolytic metabolism in the muscle and improves systemic glucose homeostasis through Deptor-mediated Akt activation.

    PubMed

    Meng, Zhuo-Xian; Li, Siming; Wang, Lin; Ko, Hwi Jin; Lee, Yongjin; Jung, Dae Young; Okutsu, Mitsuharu; Yan, Zhen; Kim, Jason K; Lin, Jiandie D

    2013-05-01

    A shift from oxidative to glycolytic metabolism has been associated with skeletal muscle insulin resistance in type 2 diabetes. However, whether this metabolic switch is deleterious or adaptive remains under debate, in part because of a limited understanding of the regulatory network that directs the metabolic and contractile specification of fast-twitch glycolytic muscle. Here we show that Baf60c (also called Smarcd3), a transcriptional cofactor enriched in fast-twitch muscle, promotes a switch from oxidative to glycolytic myofiber type through DEP domain-containing mTOR-interacting protein (Deptor)-mediated Akt activation. Muscle-specific transgenic expression of Baf60c activates a program of molecular, metabolic and contractile changes characteristic of glycolytic muscle. In addition, Baf60c is required for maintaining glycolytic capacity in adult skeletal muscle in vivo. Baf60c expression is significantly lower in skeletal muscle from obese mice compared to that from lean mice. Activation of the glycolytic muscle program by transgenic expression of Baf60c protects mice from diet-induced insulin resistance and glucose intolerance. Further mechanistic studies revealed that Deptor is induced by the Baf60c-Six4 transcriptional complex and mediates activation of Akt and glycolytic metabolism by Baf60c in a cell-autonomous manner. This work defines a fundamental mechanism underlying the specification of fast-twitch glycolytic muscle and illustrates that the oxidative-to-glycolytic metabolic shift in skeletal muscle is potentially adaptive and beneficial in the diabetic state. PMID:23563706

  12. Differential pathway coupling efficiency of the activated insulin receptor drives signaling selectivity by xmeta, an allosteric partial agonist antibody

    Technology Transfer Automated Retrieval System (TEKTRAN)

    XMetA, an anti-insulin receptor (IR) monoclonal antibody, is an allosteric partial agonist of the IR. We have previously reported that XMetA activates the “metabolic-biased” Akt kinase signaling pathway while having little or no effect on the “mitogenic” MAPK signaling pathwayof ERK 1/2. To inves...

  13. Phosphotyrosine-mediated LAT assembly on membranes drives kinetic bifurcation in recruitment dynamics of the Ras activator SOS.

    PubMed

    Huang, William Y C; Yan, Qingrong; Lin, Wan-Chen; Chung, Jean K; Hansen, Scott D; Christensen, Sune M; Tu, Hsiung-Lin; Kuriyan, John; Groves, Jay T

    2016-07-19

    The assembly of cell surface receptors with downstream signaling molecules is a commonly occurring theme in multiple signaling systems. However, little is known about how these assemblies modulate reaction kinetics and the ultimate propagation of signals. Here, we reconstitute phosphotyrosine-mediated assembly of extended linker for the activation of T cells (LAT):growth factor receptor-bound protein 2 (Grb2):Son of Sevenless (SOS) networks, derived from the T-cell receptor signaling system, on supported membranes. Single-molecule dwell time distributions reveal two, well-differentiated kinetic species for both Grb2 and SOS on the LAT assemblies. The majority fraction of membrane-recruited Grb2 and SOS both exhibit fast kinetics and single exponential dwell time distributions, with average dwell times of hundreds of milliseconds. The minor fraction exhibits much slower kinetics, extending the dwell times to tens of seconds. Considering this result in the context of the multistep process by which the Ras GEF (guanine nucleotide exchange factor) activity of SOS is activated indicates that kinetic stabilization from the LAT assembly may be important. This kinetic proofreading effect would additionally serve as a stochastic noise filter by reducing the relative probability of spontaneous SOS activation in the absence of receptor triggering. The generality of receptor-mediated assembly suggests that such effects may play a role in multiple receptor proximal signaling processes. PMID:27370798

  14. New Analysis Techniques for Avalanches in a Conical Bead Pile with Cohesion

    NASA Astrophysics Data System (ADS)

    Tieman, Catherine; Lehman, Susan

    2015-03-01

    Avalanche statistics and pile geometry for 3 mm steel spheres dropped on a conical bead pile were studied at different drop heights and different cohesion strengths. The pile is initially built on a circular base and is subsequently slowly driven by adding one bead at a time to the apex of the pile. We investigate the dynamic response of the pile by recording avalanches off the pile over the course of tens of thousands of bead drops. The level of cohesion is tuned through use of an applied uniform magnetic field. Changes in the pile mass and geometry were investigated to determine the effect of cohesion and drop height on the angle of repose. The angle of repose increased with cohesion strength, and decreased somewhat for higher drop heights. The packing density of beads is expected to decrease as magnetic cohesion increases, but for our 20 000-bead pile, this effect has not been observed. The proportion of beads removed from the pile by different avalanche sizes was also calculated. Although larger avalanches are much rarer occurrences, they carry away a larger fraction of the total avalanched mass than small avalanches. As the pile cohesion increases, the number of small and medium avalanches decreases so that this mass loss distribution shifts more strongly to large sizes.

  15. Carbon Emissions from Residue Burn Piles Estimated Using LiDAR or Ground Based Measurements of Pile Volumes in a Coastal Douglas-Fir Forest

    NASA Astrophysics Data System (ADS)

    Trofymow, J. A.; Coops, N.; Hayhurst, D.

    2012-12-01

    Following forest harvest, residues left on site and roadsides are often disposed of to reduce fire risk and free planting space. In coastal British Columbia burn piles are the main method of disposal, particularly for accumulations from log processing. Quantification of residue wood in piles is required for: smoke emission estimates, C budget calculations, billable waste assessment, harvest efficiency monitoring, and determination of bioenergy potentials. A second-growth Douglas-fir dominated (DF1949) site on eastern Vancouver Island and subject of C flux and budget studies since 1998, was clearcut in winter 2011, residues piled in spring and burned in fall. Prior to harvest, the site was divided into 4 blocks to account for harvest plans and ecosite conditions. Total harvested wood volume was scaled for each block. Residue pile wood volume was determined by a standard Waste and Residue Survey (WRS) using field estimates of pile base area and plot density (wood volume / 0.005 ha plot) on 2 piles per block, by a smoke emissions geometric method with pile volumes estimated as ellipsoidal paraboloids and packing ratios (wood volume / pile volume) for 2 piles per block, as well as by five other GIS methods using pile volumes and areas from LiDAR and orthophotography flown August 2011, a LiDAR derived digital elevation model (DEM) from 2008, and total scaled wood volumes of 8 sample piles disassembled November 2011. A weak but significant negative relationship was found between pile packing ratio and pile volume. Block level avoidable+unavoidable residue pile wood volumes from the WRS method (20.0 m3 ha-1 SE 2.8) were 30%-50% of the geometric (69.0 m3 ha-1 SE 18.0) or five GIS/LiDAR (48.0 to 65.7 m3 ha-1 ) methods. Block volumes using the 2008 LiDAR DEM (unshifted 48.0 m3 ha-1 SE 3.9, shifted 53.6 m3 ha-1 SE 4.2) to account for pre-existing humps or hollows beneath piles were not different from those using the 2011 LiDAR DEM (50.3 m3 ha-1 SE 4.0). The block volume ratio

  16. Lymphomagenic CARD11/BCL10/MALT1 signaling drives malignant B-cell proliferation via cooperative NF-κB and JNK activation

    PubMed Central

    Knies, Nathalie; Alankus, Begüm; Weilemann, Andre; Tzankov, Alexandar; Brunner, Kristina; Ruff, Tanja; Kremer, Marcus; Keller, Ulrich B.; Lenz, Georg; Ruland, Jürgen

    2015-01-01

    The aggressive activated B cell-like subtype of diffuse large B-cell lymphoma is characterized by aberrant B-cell receptor (BCR) signaling and constitutive nuclear factor kappa-B (NF-κB) activation, which is required for tumor cell survival. BCR-induced NF-κB activation requires caspase recruitment domain-containing protein 11 (CARD11), and CARD11 gain-of-function mutations are recurrently detected in human diffuse large B-cell lymphoma (DLBCL). To investigate the consequences of dysregulated CARD11 signaling in vivo, we generated mice that conditionally express the human DLBCL-derived CARD11(L225LI) mutant. Surprisingly, CARD11(L225LI) was sufficient to trigger aggressive B-cell lymphoproliferation, leading to early postnatal lethality. CARD11(L225LI) constitutively associated with B-cell CLL/lymphoma 10 (BCL10) and mucosa-associated lymphoid tissue lymphoma translocation gene 1 (MALT1) to simultaneously activate the NF-κB and c-Jun N-terminal kinase (JNK) signaling cascades. Genetic deficiencies of either BCL10 or MALT1 completely rescued the phenotype, and pharmacological inhibition of JNK was, similar to NF-κB blockage, toxic to autonomously proliferating CARD11(L225LI)-expressing B cells. Moreover, constitutive JNK activity was observed in primary human activated B cell-like (ABC)-DLBCL specimens, and human ABC-DLBCL cells were also sensitive to JNK inhibitors. Thus, our results demonstrate that enforced activation of CARD11/BCL10/MALT1 signaling is sufficient to drive transformed B-cell expansion in vivo and identify the JNK pathway as a therapeutic target for ABC-DLBCL. PMID:26668357

  17. A study of pile-up in integrated time-correlated single photon counting systems.

    PubMed

    Arlt, Jochen; Tyndall, David; Rae, Bruce R; Li, David D-U; Richardson, Justin A; Henderson, Robert K

    2013-10-01

    Recent demonstration of highly integrated, solid-state, time-correlated single photon counting (TCSPC) systems in CMOS technology is set to provide significant increases in performance over existing bulky, expensive hardware. Arrays of single photon single photon avalanche diode (SPAD) detectors, timing channels, and signal processing can be integrated on a single silicon chip with a degree of parallelism and computational speed that is unattainable by discrete photomultiplier tube and photon counting card solutions. New multi-channel, multi-detector TCSPC sensor architectures with greatly enhanced throughput due to minimal detector transit (dead) time or timing channel dead time are now feasible. In this paper, we study the potential for future integrated, solid-state TCSPC sensors to exceed the photon pile-up limit through analytic formula and simulation. The results are validated using a 10% fill factor SPAD array and an 8-channel, 52 ps resolution time-to-digital conversion architecture with embedded lifetime estimation. It is demonstrated that pile-up insensitive acquisition is attainable at greater than 10 times the pulse repetition rate providing over 60 dB of extended dynamic range to the TCSPC technique. Our results predict future CMOS TCSPC sensors capable of live-cell transient observations in confocal scanning microscopy, improved resolution of near-infrared optical tomography systems, and fluorescence lifetime activated cell sorting. PMID:24182099

  18. Reduction of acid rock drainage using steel slag in cover systems over sulfide rock waste piles.

    PubMed

    de Almeida, Rodrigo Pereira; Leite, Adilson do Lago; Borghetti Soares, Anderson

    2015-04-01

    The extraction of gold, coal, nickel, uranium, copper and other earth-moving activities almost always leads to environmental damage. In metal and coal extraction, exposure of sulfide minerals to the atmosphere leads to generation of acid rock drainage (ARD) and in underground mining to acid mine drainage (AMD) due to contamination of infiltrating groundwater. This study proposes to develop a reactive cover system that inhibits infiltration of oxygen and also releases alkalinity to increase the pH of generated ARD and attenuate metal contaminants at the same time. The reactive cover system is constructed using steel slag, a waste product generated from steel industries. This study shows that this type of cover system has the potential to reduce some of the adverse effects of sulfide mine waste disposal on land. Geochemical and geotechnical characterization tests were carried out. Different proportions of sulfide mine waste and steel slag were studied in leachate extraction tests. The best proportion was 33% of steel slag in dry weight. Other tests were conducted as follows: soil consolidation, saturated permeability and soil water characteristic curve. The cover system was numerically modeled through unsaturated flux analysis using Vadose/w. The solution proposed is an oxygen transport barrier that allows rain water percolation to treat the ARD in the waste rock pile. The results showed that the waste pile slope is an important factor and the cover system must have 5 m thickness to achieve an acceptable effectiveness. PMID:25750056

  19. A study of pile-up in integrated time-correlated single photon counting systems

    NASA Astrophysics Data System (ADS)

    Arlt, Jochen; Tyndall, David; Rae, Bruce R.; Li, David D.-U.; Richardson, Justin A.; Henderson, Robert K.

    2013-10-01

    Recent demonstration of highly integrated, solid-state, time-correlated single photon counting (TCSPC) systems in CMOS technology is set to provide significant increases in performance over existing bulky, expensive hardware. Arrays of single photon single photon avalanche diode (SPAD) detectors, timing channels, and signal processing can be integrated on a single silicon chip with a degree of parallelism and computational speed that is unattainable by discrete photomultiplier tube and photon counting card solutions. New multi-channel, multi-detector TCSPC sensor architectures with greatly enhanced throughput due to minimal detector transit (dead) time or timing channel dead time are now feasible. In this paper, we study the potential for future integrated, solid-state TCSPC sensors to exceed the photon pile-up limit through analytic formula and simulation. The results are validated using a 10% fill factor SPAD array and an 8-channel, 52 ps resolution time-to-digital conversion architecture with embedded lifetime estimation. It is demonstrated that pile-up insensitive acquisition is attainable at greater than 10 times the pulse repetition rate providing over 60 dB of extended dynamic range to the TCSPC technique. Our results predict future CMOS TCSPC sensors capable of live-cell transient observations in confocal scanning microscopy, improved resolution of near-infrared optical tomography systems, and fluorescence lifetime activated cell sorting.

  20. Dynamic protein conformations preferentially drive energy transfer along the active chain of the photosystem II reaction centre.

    PubMed

    Zhang, Lu; Silva, Daniel-Adriano; Zhang, Houdao; Yue, Alexander; Yan, YiJing; Huang, Xuhui

    2014-01-01

    One longstanding puzzle concerning photosystem II, a core component of photosynthesis, is that only one of the two symmetric branches in its reaction centre is active in electron transfer. To investigate the effect of the photosystem II environment on the preferential selection of the energy transfer pathway (a prerequisite for electron transfer), we have constructed an exciton model via extensive molecular dynamics simulations and quantum mechanics/molecular mechanics calculations based on a recent X-ray structure. Our results suggest that it is essential to take into account an ensemble of protein conformations to accurately compute the site energies. We identify the cofactor CLA606 of active chain as the most probable site for the energy excitation. We further pinpoint a number of charged protein residues that collectively lower the CLA606 site energy. Our work provides insights into the understanding of molecular mechanisms of the core machinery of the green-plant photosynthesis. PMID:24954746

  1. Clostridium sordellii Lethal-Toxin Autoprocessing and Membrane Localization Activities Drive GTPase Glucosylation Profiles in Endothelial Cells

    PubMed Central

    Craven, Ryan

    2015-01-01

    ABSTRACT Clostridium sordellii infections cause gangrene and edema in humans and gastrointestinal infections in livestock. One of the principle virulence factors is TcsL, a large protein toxin which glucosylates host GTPases to cause cytopathic and cytotoxic effects. TcsL has two enzymatic domains, an N-terminal glucosyltransferase domain (GTD) and an autoprocessing domain responsible for release of the GTD within the cell. The GTD can then use its N-terminal membrane localization domain (MLD) for orientation on membranes and modification of GTPases. This study describes the use of conditionally immortalized murine pulmonary microvascular endothelial cells as a model for the study of TcsL functional activities. Point mutations that disrupt the glucosyltransferase, autoprocessing, or membrane localization activities were introduced into a recombinant version of TcsL, and the activities of these mutants were compared to those of wild-type toxin. We observed that all mutants are defective or impaired in cytotoxicity but differ in their modification of Rac1 and Ras. The data suggest a model where differences in GTPase localization dictate cellular responses to intoxication and highlight the importance of autoprocessing in the function of TcsL. IMPORTANCE Clostridium sordellii is a bacterium that can infect humans and cause serious disease and death. The principle virulence factor associated with clinical symptoms is a large protein toxin known as lethal toxin. The mechanism of lethal-toxin intoxication is assumed to be similar to that of the homologous toxins from C. difficile, but very few studies have been done in the context of endothelial cells, a relevant target in C. sordellii infections. This study was designed to test the role of the lethal-toxin enzymatic activities and membrane localization in endothelial cell toxicity and host substrate modification. PMID:27303685

  2. NLRP3 inflammasome activation drives bystander cone photoreceptor cell death in a P23H rhodopsin model of retinal degeneration.

    PubMed

    Viringipurampeer, Ishaq A; Metcalfe, Andrew L; Bashar, Abu E; Sivak, Olena; Yanai, Anat; Mohammadi, Zeinabsadat; Moritz, Orson L; Gregory-Evans, Cheryl Y; Gregory-Evans, Kevin

    2016-04-15

    The molecular signaling leading to cell death in hereditary neurological diseases such as retinal degeneration is incompletely understood. Previous neuroprotective studies have focused on apoptotic pathways; however, incomplete suppression of cell death with apoptosis inhibitors suggests that other mechanisms are at play. Here, we report that different signaling pathways are activated in rod and cone photoreceptors in the P23H rhodopsin mutant rat, a model representing one of the commonest forms of retinal degeneration. Up-regulation of the RIP1/RIP3/DRP1 axis and markedly improved survival with necrostatin-1 treatment highlighted necroptosis as a major cell-death pathway in degenerating rod photoreceptors. Conversely, up-regulation of NLRP3 and caspase-1, expression of mature IL-1β and IL-18 and improved cell survival with N-acetylcysteine treatment suggested that inflammasome activation and pyroptosis was the major cause of cone cell death. This was confirmed by generation of the P23H mutation on an Nlrp3-deficient background, which preserved cone viability. Furthermore, Brilliant Blue G treatment inhibited inflammasome activation, indicating that the 'bystander cell death' phenomenon was mediated through the P2RX7 cell-surface receptor. Here, we identify a new pathway in cones for bystander cell death, a phenomenon important in development and disease in many biological systems. In other retinal degeneration models different cell-death pathways are activated, which suggests that the particular pathways that are triggered are to some extent genotype-specific. This also implies that neuroprotective strategies to limit retinal degeneration need to be customized; thus, different combinations of inhibitors will be needed to target the specific pathways in any given disease. PMID:27008885

  3. The β2-adrenoceptor activates a positive cAMP-calcium feedforward loop to drive breast cancer cell invasion.

    PubMed

    Pon, Cindy K; Lane, J Robert; Sloan, Erica K; Halls, Michelle L

    2016-03-01

    Activation of the sympathetic nervous system by stress increases breast cancer metastasis in vivo. Preclinical studies suggest that stress activates β-adrenoceptors (βARs) to enhance metastasis from primary tumors and that β-blockers may be protective in breast cancer. However, the subtype of βAR that mediates this effect, as well as the signaling mechanisms underlying increased tumor cell dissemination, remain unclear. We show that the β2AR is the only functionally relevant βAR subtype in the highly metastatic human breast cancer cell line MDA-MB-231HM. β2AR activation results in elevated cAMP (formoterol pEC50 9.86 ± 0.32), increased intracellular Ca(2+) (formoterol pEC50 8.20 ± 0.33) and reduced phosphorylated ERK (pERK; formoterol pIC50 11.62 ± 0.31). We demonstrate that a highly amplified positive feedforward loop between the cAMP and Ca(2+) pathways is responsible for efficient inhibition of basal pERK. Importantly, activation of the β2AR increased invasion (formoterol area under the curve [AUC] relative to vehicle: 1.82 ± 0.36), which was dependent on the cAMP/Ca(2+) loop (formoterol AUC in the presence of 2'5'-dideoxyadenosine 0.64 ± 0.03, or BAPTA-AM 0.45 ± 0.23) but independent of inhibition of basal pERK1/2 (vehicle AUC with U0126 0.60 ± 0.30). Specifically targeting the positive feedforward cAMP/Ca(2+) loop may be beneficial for the development of therapeutics to slow disease progression in patients with breast cancer. PMID:26578688

  4. Crazy heart: kinematics of the "star pile" in Abell 545

    NASA Astrophysics Data System (ADS)

    Salinas, R.; Richtler, T.; West, M. J.; Romanowsky, A. J.; Lloyd-Davies, E.; Schuberth, Y.

    2011-04-01

    We study the structure and internal kinematics of the "star pile" in Abell 545 - a low surface brightness structure lying in the center of the cluster. We have obtained deep long-slit spectroscopy of the star pile using VLT/FORS2 and Gemini/GMOS, which is analyzed in conjunction with deep multiband CFHT/MEGACAM imaging. As presented in a previous study the star pile has a flat luminosity profile and its color is consistent with the outer parts of elliptical galaxies. Its velocity map is irregular, with parts being seemingly associated with an embedded nucleus, and others which have significant velocity offsets to the cluster systemic velocity with no clear kinematical connection to any of the surrounding galaxies. This would make the star pile a dynamically defined stellar intra-cluster component. The complicated pattern in velocity and velocity dispersions casts doubts on the adequacy of using the whole star pile as a dynamical test for the innermost dark matter profile of the cluster. This status is fulfilled only by the nucleus and its nearest surroundings which lie at the center of the cluster velocity distribution. Based on observations taken at the European Southern Observatory, Cerro Paranal, Chile, under programme ID 080.B-0529. Also based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil) and SECYT (Argentina); and on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National

  5. Impact Simulations on the Rubble Pile Asteroid (2867) Steins

    NASA Astrophysics Data System (ADS)

    Deller, Jakob; Snodgrass, Colin; Lowry, Stephen C.; Price, Mark C.; Sierks, Holger

    2014-11-01

    Images from the OSIRIS camera system on board the Rosetta spacecraft (Keller et al. 2010) has revealed several interesting features on asteroid (2867) Steins. Its macro porosity of 40%, together with the shape that looks remarkably like a YORP evolved body, both indicate a rubble pile structure. A large crater on the southern pole is evidence for collisional evolution of this rubble pile asteroid. We have developed a new approach for simulating impacts on asteroid bodies that connects formation history to their collisional evolution. This is achieved by representing the interior as a ‘rubble pile’, created from the gravitational aggregation of spherical ‘pebbles’ that represent fragments from a major disruption event. These ‘pebbles’ follow a power law size function and constitute the building blocks of the rubble pile. This allows us to explicitly model the interior of rubble pile asteroids in hyper-velocity impact simulations in a more realistic way. We present preliminary results of a study validating our approach in a large series of simulated impacts on a typical small main belt rubble pile asteroid using the Smoothed Particle Hydrodynamics solver in Autodyn. We show that this approach allows us to explicitly follow the behavior of a single ‘pebble’, while preserving the expected properties of the bulk asteroid as known from observations and experiments (Holsapple 2009). On the example of Steins, we use this model to investigate if surface features like the northern hill at 75/100 degrees lon/lat distance to the largest crater (Jorda et al. 2012), or the catena of depletion pits, can be explained by the displacement of large fragments in the interior of the asteroid during the impact. We do this by following the movement of pebbles below the surface feature in simulations that recreate the shape of the impact crater.Acknowledgements: Jakob Deller thanks the Planetary Science Institute for a Pierazzo International Student Travel Award that funds

  6. Feasibility Study of Thin Film Thermocouple Piles

    NASA Technical Reports Server (NTRS)

    Sisk, R. C.

    2001-01-01

    Historically, thermopile detectors, generators, and refrigerators based on bulk materials have been used to measure temperature, generate power for spacecraft, and cool sensors for scientific investigations. New potential uses of small, low-power, thin film thermopiles are in the area of microelectromechanical systems since power requirements decrease as electrical and mechanical machines shrink in size. In this research activity, thin film thermopile devices are fabricated utilizing radio frequency sputter coating and photoresist lift-off techniques. Electrical characterizations are performed on two designs in order to investigate the feasibility of generating small amounts of power, utilizing any available waste heat as the energy source.

  7. OVERALL CONTROL SYSTEM FOR HIGH FLUX PILE

    DOEpatents

    Newson, H.W.; Durham, N.C.; Wigner, E.P.; Princeton, N.J.; Epler, E.P.

    1961-05-23

    A control system is given for a high fiux reactor incorporating an anti- scram control feature whereby a neutron absorbing control rod acts as a fine adjustment while a neutron absorbing shim rod, actuated upon a command received from reactor period and level signals, has substantially greater effect on the neutron level and is moved prior to scram conditions to alter the reactor activity before a scram condition is created. Thus the probability that a scram will have to be initiated is substantially decreased.

  8. Nitroglycerin drives endothelial nitric oxide synthase activation via the phosphatidylinositol 3-kinase/protein kinase B pathway.

    PubMed

    Mao, Mao; Sudhahar, Varadarajan; Ansenberger-Fricano, Kristine; Fernandes, Denise C; Tanaka, Leonardo Y; Fukai, Tohru; Laurindo, Francisco R M; Mason, Ronald P; Vasquez-Vivar, Jeannette; Minshall, Richard D; Stadler, Krisztian; Bonini, Marcelo G

    2012-01-15

    Nitroglycerin (GTN) has been clinically used to treat angina pectoris and acute heart episodes for over 100 years. The effects of GTN have long been recognized and active research has contributed to the unraveling of numerous metabolic routes capable of converting GTN to the potent vasoactive messenger nitric oxide. Recently, the mechanism by which minute doses of GTN elicit robust pharmacological responses was revisited and eNOS activation was implicated as an important route mediating vasodilation induced by low GTN doses (1-50nM). Here, we demonstrate that at such concentrations the pharmacologic effects of nitroglycerin are largely dependent on the phosphatidylinositol 3-kinase, Akt/PKB, and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) signal transduction axis. Furthermore, we demonstrate that nitroglycerin-dependent accumulation of 3,4,5-InsP(3), probably because of inhibition of PTEN, is important for eNOS activation, conferring a mechanistic basis for GTN pharmacological action at pharmacologically relevant doses. PMID:22037515

  9. Nitroglycerin drives endothelial nitric oxide synthase activation via the phosphatidylinositol 3-kinase/protein kinase B pathway

    PubMed Central

    Mao, Mao; Sudhahar, Varadarajan; Ansenberger-Fricano, Kristine; Fernandes, Denise C.; Tanaka, Leonardo Y.; Fukai, Tohru; Laurindo, Francisco R.M.; Mason, Ronald P.; Vasquez-Vivar, Jeannette; Minshall, Richard D.; Stadler, Krisztian; Bonini, Marcelo G.

    2012-01-01

    Nitroglycerin (GTN) has been clinically used to treat angina pectoris and acute heart episodes for over 100 years. The effects of GTN have long been recognized and active research has contributed to the unraveling of numerous metabolic routes capable of converting GTN to the potent vasoactive messenger nitric oxide. Recently, the mechanism by which minute doses of GTN elicit robust pharmacological responses was revisited and eNOS activation was implicated as an important route mediating vasodilation induced by low GTN doses (1–50 nM). Here, we demonstrate that at such concentrations the pharmacologic effects of nitroglycerin are largely dependent on the phosphatidylinositol 3-kinase, Akt/PKB, and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) signal transduction axis. Furthermore, we demonstrate that nitroglycerin-dependent accumulation of 3,4,5-InsP3, probably because of inhibition of PTEN, is important for eNOS activation, conferring a mechanistic basis for GTN pharmacological action at pharmacologically relevant doses. PMID:22037515

  10. Numerical modeling of Thermal Response Tests in Energy Piles

    NASA Astrophysics Data System (ADS)

    Franco, A.; Toledo, M.; Moffat, R.; Herrera, P. A.

    2013-05-01

    Nowadays, thermal response tests (TRT) are used as the main tools for the evaluation of low enthalpy geothermal systems such as heat exchangers. The results of TRT are used for estimating thermal conductivity and thermal resistance values of those systems. We present results of synthetic TRT simulations that model the behavior observed in an experimental energy pile system, which was installed at the new building of the Faculty of Engineering of Universidad de Chile. Moreover, we also present a parametric study to identify the most influent parameters in the performance of this type of tests. The modeling was developed using the finite element software COMSOL Multiphysics, which allows the incorporation of flow and heat transport processes. The modeled system consists on a concrete pile with 1 m diameter and 28 m deep, which contains a 28 mm diameter PEX pipe arranged in a closed circuit. Three configurations were analyzed: a U pipe, a triple U and a helicoid shape implemented at the experimental site. All simulations were run considering transient response in a three-dimensional domain. The simulation results provided the temperature distribution on the pile for a set of different geometry and physical properties of the materials. These results were compared with analytical solutions which are commonly used to interpret TRT data. This analysis demonstrated that there are several parameters that affect the system response in a synthetic TRT. For example, the diameter of the simulated pile affects the estimated effective thermal conductivity of the system. Moreover, the simulation results show that the estimated thermal conductivity for a 1 m diameter pile did not stabilize even after 100 hours since the beginning of the test, when it reached a value 30% below value used to set up the material properties in the simulation. Furthermore, we observed different behaviors depending on the thermal properties of concrete and soil. According to the simulations, the thermal

  11. The Pelargonium sidoides Extract EPs 7630 Drives the Innate Immune Defense by Activating Selected MAP Kinase Pathways in Human Monocytes

    PubMed Central

    Witte, Katrin; Koch, Egon; Volk, Hans-Dieter; Wolk, Kerstin; Sabat, Robert

    2015-01-01

    Pelargonium sidoides is a medical herb and respective extracts are used very frequently for the treatment of respiratory tract infections. However, the effects of Pelargonium sidoides and a special extract prepared from its roots (EPs 7630) on human immune cells are not fully understood. Here we demonstrate that EPs 7630 induced a rapid and dose-dependent production of TNF-α, IL-6, and IL-10 by human blood immune cells. This EPs 7630-induced cytokine profile was more pro-inflammatory in comparison with the profile induced by viral or bacterial infection-mimicking agents. The search for EPs 7630 target cells revealed that T-cells did not respond to EPs 7630 stimulation by production of TNF-α, IL-6, or IL-10. Furthermore, pretreatment of T-cells with EPs 7630 did not modulate their TNF-α, IL-6, and IL-10 secretion during subsequent activation. In contrast to lymphocytes, monocytes showed clear intracellular TNF-α staining after EPs 7630 treatment. Accordingly, EPs 7630 predominantly provoked activation of MAP kinases and inhibition of p38 strongly reduced the monocyte TNF-α production. The pretreatment of blood immune cells with EPs 7630 lowered their secretion of TNF-α and IL-10 and caused an IL-6 dominant response during second stimulation with viral or bacterial infection-mimicking agents. In summary, we demonstrate that EPs 7630 activates human monocytes, induces MAP kinase-dependent pro-inflammatory cytokines in these cells, and specifically modulates their production capacity of mediators known to lead to an increase of acute phase protein production in the liver, neutrophil generation in the bone marrow, and the generation of adaptive Th17 and Th22 cells. PMID:26406906

  12. The Pelargonium sidoides Extract EPs 7630 Drives the Innate Immune Defense by Activating Selected MAP Kinase Pathways in Human Monocytes.

    PubMed

    Witte, Katrin; Koch, Egon; Volk, Hans-Dieter; Wolk, Kerstin; Sabat, Robert

    2015-01-01

    Pelargonium sidoides is a medical herb and respective extracts are used very frequently for the treatment of respiratory tract infections. However, the effects of Pelargonium sidoides and a special extract prepared from its roots (EPs 7630) on human immune cells are not fully understood. Here we demonstrate that EPs 7630 induced a rapid and dose-dependent production of TNF-α, IL-6, and IL-10 by human blood immune cells. This EPs 7630-induced cytokine profile was more pro-inflammatory in comparison with the profile induced by viral or bacterial infection-mimicking agents. The search for EPs 7630 target cells revealed that T-cells did not respond to EPs 7630 stimulation by production of TNF-α, IL-6, or IL-10. Furthermore, pretreatment of T-cells with EPs 7630 did not modulate their TNF-α, IL-6, and IL-10 secretion during subsequent activation. In contrast to lymphocytes, monocytes showed clear intracellular TNF-α staining after EPs 7630 treatment. Accordingly, EPs 7630 predominantly provoked activation of MAP kinases and inhibition of p38 strongly reduced the monocyte TNF-α production. The pretreatment of blood immune cells with EPs 7630 lowered their secretion of TNF-α and IL-10 and caused an IL-6 dominant response during second stimulation with viral or bacterial infection-mimicking agents. In summary, we demonstrate that EPs 7630 activates human monocytes, induces MAP kinase-dependent pro-inflammatory cytokines in these cells, and specifically modulates their production capacity of mediators known to lead to an increase of acute phase protein production in the liver, neutrophil generation in the bone marrow, and the generation of adaptive Th17 and Th22 cells. PMID:26406906

  13. Independent Verification Survey of the Clean Coral Storage Pile at the Johnston Atoll Plutonium-Contaminated Soil Remediation Project

    SciTech Connect

    Wilson-Nichols, M.J.

    2000-12-07

    The Oak Ridge National Laboratory (ORNL) Environmental Technology Section conducted an independent verification (IV) survey of the clean storage pile at the Johnston Atoll Plutonium Contaminated Soil Remediation Project (JAPCSRP) from January 18-25, 1999. The goal of the JAPCSRP is to restore a 24-acre area that was contaminated with plutonium oxide particles during nuclear testing in the 1960s. The selected remedy was a soil sorting operation that combined radiological measurements and mining processes to identify and sequester plutonium-contaminated soil. The soil sorter operated from about 1990 to 1998. The remaining clean soil is stored on-site for planned beneficial use on Johnston Island. The clean storage pile currently consists of approximately 120,000 m{sup 3} of coral. ORNL conducted the survey according to a Sampling and Analysis Plan, which proposed to provide an IV of the clean pile by collecting a minimum number (99) of samples. The goal was to ascertain with 95% confidence whether 97% of the processed soil is less than or equal to the accepted guideline (500-Bq/kg or 13.5-pCi/g) total transuranic (TRU) activity. In previous IV tasks, ORNL has (1) evaluated and tested the soil sorter system software and hardware and (2) evaluated the quality control (QC) program used at the soil sorter plant. The IV has found that the soil sorter decontamination was effective and significantly reduced plutonium contamination in the soil processed at the JA site. The Field Command Defense Threat Reduction Agency currently plans to re-use soil from the clean pile as a cover to remaining contamination in portions of the radiological control area. Therefore, ORNL was requested to provide an IV. The survey team collected samples from 103 random locations within the top 4 ft of the clean storage pile. The samples were analyzed in the on-site radioanalytical counting laboratory with an American Nuclear Systems (ANS) field instrument used for the detection of low

  14. Extended Driving Impairs Nocturnal Driving Performances

    PubMed Central

    Sagaspe, Patricia; Taillard, Jacques; Åkerstedt, Torbjorn; Bayon, Virginie; Espié, Stéphane; Chaumet, Guillaume; Bioulac, Bernard; Philip, Pierre

    2008-01-01

    Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3–5am, 1–5am and 9pm–5am) on open highway. Fourteen young healthy men (mean age [±SD] = 23.4 [±1.7] years) participated Inappropriate line crossings (ILC) in the last hour of driving of each session, sleep variables, self-perceived fatigue and sleepiness were measured. Compared to the short (3–5am) driving session, the incidence rate ratio of inappropriate line crossings increased by 2.6 (95% CI, 1.1 to 6.0; P<.05) for the intermediate (1–5am) driving session and by 4.0 (CI, 1.7 to 9.4; P<.001) for the long (9pm–5am) driving session. Compared to the reference session (9–10pm), the incidence rate ratio of inappropriate line crossings were 6.0 (95% CI, 2.3 to 15.5; P<.001), 15.4 (CI, 4.6 to 51.5; P<.001) and 24.3 (CI, 7.4 to 79.5; P<.001), respectively, for the three different durations of driving. Self-rated fatigue and sleepiness scores were both positively correlated to driving impairment in the intermediate and long duration sessions (P<.05) and increased significantly during the nocturnal driving sessions compared to the reference session (P<.01). At night, extended driving impairs driving performances and therefore should be limited. PMID:18941525

  15. Caspase-9b Interacts Directly with cIAP1 to Drive Agonist-Independent Activation of NF-κB and Lung Tumorigenesis.

    PubMed

    Vu, Ngoc T; Park, Margaret A; Shultz, Michael D; Bulut, Gamze B; Ladd, Amy C; Chalfant, Charles E

    2016-05-15

    Alternate RNA processing of caspase-9 generates the splice variants caspase 9a (C9a) and caspase 9b (C9b). C9b lacks a domain present in C9a, revealing a tumorigenic function that drives the phenotype of non-small cell lung cancer (NSCLC) cells. In this study, we elucidated the mechanistic underpinnings of the malignant character of this splice isoform. In NSCLC cells, C9b expression correlated with activation of the canonical arm of the NF-κB pathway, a major pathway linked to the NSCLC tumorigenesis. Mechanistic investigations revealed that C9b activates this pathway via direct interaction with cellular inhibitor of apoptosis 1 (cIAP1) and subsequent induction of the E3 ligase activity of this IAP family member. The C9b:cIAP1 interaction occurred via the BIR3 domain of cIAP1 and the IAP-binding motif of C9b, but did not require proteolytic cleavage of C9b. This protein:protein interaction was essential for C9b to promote viability and malignant growth of NSCLC cells in vitro and in vivo, broadly translating to diverse NSCLC oncogenotypes. Overall, our findings identified a novel point for therapeutic invention in NSCLC that may be tractable to small-molecule inhibitors, as a new point to broadly address this widespread deadly disease. Cancer Res; 76(10); 2977-89. ©2016 AACR. PMID:27197231

  16. Clonality Analysis of Immunoglobulin Gene Rearrangement by Next-Generation Sequencing in Endemic Burkitt Lymphoma Suggests Antigen Drive Activation of BCR as Opposed to Sporadic Burkitt Lymphoma

    PubMed Central

    Amato, Teresa; Abate, Francesco; Piccaluga, Pierpaolo; Iacono, Michele; Fallerini, Chiara; Renieri, Alessandra; De Falco, Giulia; Ambrosio, Maria Raffaella; Mourmouras, Vaselious; Ogwang, Martin; Calbi, Valeria; Rabadan, Roul; Hummel, Michael; Pileri, Stefano; Bellan, Cristiana

    2016-01-01

    Objectives: Recent studies using next-generation sequencing (NGS) analysis disclosed the importance of the intrinsic activation of the B-cell receptor (BCR) pathway in the pathogenesis of sporadic Burkitt lymphoma (sBL) due to mutations of TCF3/ID3 genes. Since no definitive data are available on the genetic landscape of endemic Burkitt (eBL), we first assessed the mutation frequency of TCF3/ID3 in eBL compared with sBL and subsequently the somatic hypermutation status of the BCR to answer whether an extrinsic activation of BCR signaling could also be demonstrated in Burkitt lymphoma. Methods: We assessed the mutations of TCF3/ID3 by RNAseq and the BCR status by NGS analysis of the immunoglobulin genes (IGs). Results: We detected mutations of TCF3/ID3 in about 30% of the eBL cases. This rate is significantly lower than that detected in sBL (64%). The NGS analysis of IGs revealed intraclonal diversity, suggesting an active targeted somatic hypermutation process in eBL compared with sBL. Conclusions: These findings support the view that the antigenic pressure plays a key role in the pathogenetic pathways of eBL, which may be partially distinct from those driving sBL development. PMID:26712879

  17. Pro-fibrotic pathway activation in trabecular meshwork and lamina cribrosa is the main driving force of glaucoma.

    PubMed

    Zhavoronkov, Alex; Kanherkar, Riya R; Izumchenko, Evgeny; Teka, Mahder; Cantor, Charles; Manaye, Kebreten; Sidransky, David; West, Michael D; Makarev, Eugene; Csoka, Antonei Benjamin

    2016-06-17

    While primary open-angle glaucoma (POAG) is a leading cause of blindness worldwide, it still does not have a clear mechanism that can explain all clinical cases of the disease. Elevated IOP is associated with increased accumulation of extracellular matrix (ECM) proteins in the trabecular meshwork (TM) that prevents normal outflow of aqueous humor (AH) and has damaging effects on the fine mesh-like lamina cribrosa (LC) through which the optic nerve fibers pass. Applying a pathway analysis algorithm, we discovered that an elevated level of TGFβ observed in glaucoma-affected tissues could lead to pro-fibrotic pathway activation in TM and in LC. In turn, activated pro-fibrotic pathways lead to ECM remodeling in TM and LC, making TM less efficient in AH drainage and making LC more susceptible to damage from elevated IOP via ECM transformation in LC. We propose pathway targets for potential therapeutic interventions to delay or avoid fibrosis initiation in TM and LC tissues. PMID:27229292

  18. Activation of β-Catenin Signaling in CD133-Positive Dermal Papilla Cells Drives Postnatal Hair Growth.

    PubMed

    Zhou, Linli; Xu, Mingang; Yang, Yongguang; Yang, Kun; Wickett, Randall R; Andl, Thomas; Millar, Sarah E; Zhang, Yuhang

    2016-01-01

    The hair follicle dermal papilla (DP) contains a unique prominin-1/CD133-positive (CD133+) cell subpopulation, which has been shown to possess hair follicle-inducing capability. By assaying for endogenous CD133 expression and performing lineage tracing using CD133-CreERT2; ZsGreen1 reporter mice, we find that CD133 is expressed in a subpopulation of DP cells during the growth phase of the murine hair cycle (anagen), but is absent at anagen onset. However, how CD133+ DP cells interact with keratinocytes to induce hair regenerative growth remains unclear. Wnt/β-catenin has long been recognized as a major signaling pathway required for hair follicle morphogenesis, development, and regeneration. Nuclear Wnt/β-catenin activity is observed in the DP during the hair growth phase. Here we show that induced expression of a stabilized form of β-catenin in CD133+ DP cells significantly accelerates spontaneous and depilation-induced hair growth. However, hair follicle regression is not affected in these mutants. Further analysis indicates that CD133+ DP-expressed β-catenin increases proliferation and differentiation of epithelial matrix keratinocytes. Upregulated Wnt/β-catenin activity in CD133+ DP cells also increases the number of proliferating DP cells in each anagen follicle. Our data demonstrate that β-catenin signaling potentiates the capability of CD133+ DP cells to promote postnatal hair growth. PMID:27472062

  19. Interplay of active processes modulates tension and drives phase transition in self-renewing, motor-driven cytoskeletal networks

    PubMed Central

    Mak, Michael; Zaman, Muhammad H.; Kamm, Roger D.; Kim, Taeyoon

    2016-01-01

    The actin cytoskeleton—a complex, nonequilibrium network consisting of filaments, actin-crosslinking proteins (ACPs) and motors—confers cell structure and functionality, from migration to morphogenesis. While the core components are recognized, much less is understood about the behaviour of the integrated, disordered and internally active system with interdependent mechano-chemical component properties. Here we use a Brownian dynamics model that incorporates key and realistic features—specifically actin turnover, ACP (un)binding and motor walking—to reveal the nature and underlying regulatory mechanisms of overarching cytoskeletal states. We generate multi-dimensional maps that show the ratio in activity of these microscopic elements determines diverse global stress profiles and the induction of nonequilibrium morphological phase transition from homogeneous to aggregated networks. In particular, actin turnover dynamics plays a prominent role in tuning stress levels and stabilizing homogeneous morphologies in crosslinked, motor-driven networks. The consequence is versatile functionality, from dynamic steady-state prestress to large, pulsed constrictions. PMID:26744226

  20. Pro-fibrotic pathway activation in trabecular meshwork and lamina cribrosa is the main driving force of glaucoma

    PubMed Central

    Zhavoronkov, Alex; Izumchenko, Evgeny; Kanherkar, Riya R.; Teka, Mahder; Cantor, Charles; Manaye, Kebreten; Sidransky, David; West, Michael D.; Makarev, Eugene; Csoka, Antonei Benjamin

    2016-01-01

    ABSTRACT While primary open-angle glaucoma (POAG) is a leading cause of blindness worldwide, it still does not have a clear mechanism that can explain all clinical cases of the disease. Elevated IOP is associated with increased accumulation of extracellular matrix (ECM) proteins in the trabecular meshwork (TM) that prevents normal outflow of aqueous humor (AH) and has damaging effects on the fine mesh-like lamina cribrosa (LC) through which the optic nerve fibers pass. Applying a pathway analysis algorithm, we discovered that an elevated level of TGFβ observed in glaucoma-affected tissues could lead to pro-fibrotic pathway activation in TM and in LC. In turn, activated pro-fibrotic pathways lead to ECM remodeling in TM and LC, making TM less efficient in AH drainage and making LC more susceptible to damage from elevated IOP via ECM transformation in LC. We propose pathway targets for potential therapeutic interventions to delay or avoid fibrosis initiation in TM and LC tissues. PMID:27229292

  1. Targeting leukemia stem cells: which pathways drive self-renewal activity in T-cell acute lymphoblastic leukemia?

    PubMed Central

    Belmonte, M.; Hoofd, C.; Weng, A.P.; Giambra, V.

    2016-01-01

    T-Cell acute lymphoblastic leukemia (t-all) is a malignancy of white blood cells, characterized by an uncontrolled accumulation of T-cell progenitors. During leukemic progression, immature T cells grow abnormally and crowd into the bone marrow, preventing it from making normal blood cells and spilling out into the bloodstream. Recent studies suggest that only discrete cell populations that possess the ability to recreate the entire tumour might be responsible for the initiation and propagation of t-all. Those unique cells are commonly called “cancer stem cells” or, in the case of hematopoietic malignancies, “leukemia stem cells” (lscs). Like normal hematopoietic stem cells, lscs are thought to be capable of self-renewal, during which, by asymmetrical division, they give rise to an identical copy of themselves as well as to a daughter cell that is no longer capable of self-renewal activity and represents a more “differentiated” progeny. Here, we review the main pathways of self-renewal activity in lscs, focusing on their involvement in the maintenance and development of t-all. New stem cell–directed therapies and lsc-targeted agents are also discussed. PMID:26966402

  2. Reprogramming metabolism by histone methyltransferase NSD2 drives endocrine resistance via coordinated activation of pentose phosphate pathway enzymes.

    PubMed

    Wang, Junjian; Duan, Zhijian; Nugent, Zoann; Zou, June X; Borowsky, Alexander D; Zhang, Yanhong; Tepper, Clifford G; Li, Jian Jian; Fiehn, Oliver; Xu, Jianzhen; Kung, Hsing-Jien; Murphy, Leigh C; Chen, Hong-Wu

    2016-08-10

    Metabolic reprogramming such as the aerobic glycolysis or Warburg effect is well recognized as a common feature of tumorigenesis. However, molecular mechanisms underlying metabolic alterations for tumor therapeutic resistance are poorly understood. Through gene expression profiling analysis we found that histone H3K36 methyltransferase NSD2/MMSET/WHSC1 expression was highly elevated in tamoxifen-resistant breast cancer cell lines and clinical tumors. IHC analysis indicated that NSD2 protein overexpression was associated with the disease recurrence and poor survival. Ectopic expression of NSD2 wild type, but not the methylase-defective mutant, drove endocrine resistance in multiple cell models and xenograft tumors. Mechanistically, NSD2 was recruited to and methylated H3K36me2 at the promoters of key glucose metabolic enzyme genes. Its overexpression coordinately up-regulated hexokinase 2 (HK2) and glucose-6-phosphate dehydrogenase (G6PD), two key enzymes of glycolysis and the pentose phosphate pathway (PPP), as well as TP53-induced glycolysis regulatory phosphatase TIGAR. Consequently, NSD2-driven tamoxifen-resistant cells and tumors displayed heightened PPP activity, elevated NADPH production, and reduced ROS level, without significantly altered glycolysis. These results illustrate a coordinated, epigenetic activation of key glucose metabolic enzymes in therapeutic resistance and nominate methyltransferase NSD2 as a potential therapeutic target for endocrine resistant breast cancer. PMID:27164560

  3. Activation of β-Catenin Signaling in CD133-Positive Dermal Papilla Cells Drives Postnatal Hair Growth

    PubMed Central

    Zhou, Linli; Xu, Mingang; Yang, Yongguang; Yang, Kun; Wickett, Randall R.; Andl, Thomas; Millar, Sarah E.

    2016-01-01

    The hair follicle dermal papilla (DP) contains a unique prominin-1/CD133-positive (CD133+) cell subpopulation, which has been shown to possess hair follicle-inducing capability. By assaying for endogenous CD133 expression and performing lineage tracing using CD133-CreERT2; ZsGreen1 reporter mice, we find that CD133 is expressed in a subpopulation of DP cells during the growth phase of the murine hair cycle (anagen), but is absent at anagen onset. However, how CD133+ DP cells interact with keratinocytes to induce hair regenerative growth remains unclear. Wnt/β-catenin has long been recognized as a major signaling pathway required for hair follicle morphogenesis, development, and regeneration. Nuclear Wnt/β-catenin activity is observed in the DP during the hair growth phase. Here we show that induced expression of a stabilized form of β-catenin in CD133+ DP cells significantly accelerates spontaneous and depilation-induced hair growth. However, hair follicle regression is not affected in these mutants. Further analysis indicates that CD133+ DP-expressed β-catenin increases proliferation and differentiation of epithelial matrix keratinocytes. Upregulated Wnt/β-catenin activity in CD133+ DP cells also increases the number of proliferating DP cells in each anagen follicle. Our data demonstrate that β-catenin signaling potentiates the capability of CD133+ DP cells to promote postnatal hair growth. PMID:27472062

  4. Photochemical activity of a key donor-acceptor complex can drive stereoselective catalytic α-alkylation of aldehydes

    NASA Astrophysics Data System (ADS)

    Arceo, Elena; Jurberg, Igor D.; Álvarez-Fernández, Ana; Melchiorre, Paolo

    2013-09-01

    Asymmetric catalytic variants of sunlight-driven photochemical processes hold extraordinary potential for the sustainable preparation of chiral molecules. However, the involvement of short-lived electronically excited states inherent to any photochemical reaction makes it challenging for a chiral catalyst to dictate the stereochemistry of the products. Here, we report that readily available chiral organic catalysts, with well-known utility in thermal asymmetric processes, can also confer a high level of stereocontrol in synthetically relevant intermolecular carbon-carbon bond-forming reactions driven by visible light. A unique mechanism of catalysis is proposed, wherein the catalyst is involved actively in both the photochemical activation of the substrates (by inducing the transient formation of chiral electron donor-acceptor complexes) and the stereoselectivity-defining event. We use this approach to enable transformations that are extremely difficult under thermal conditions, such as the asymmetric α-alkylation of aldehydes with alkyl halides, the formation of all-carbon quaternary stereocentres and the control of remote stereochemistry.

  5. Driving Care Quality: Aligning Trainee Assessment and Supervision Through Practical Application of Entrustable Professional Activities, Competencies, and Milestones.

    PubMed

    Carraccio, Carol; Englander, Robert; Holmboe, Eric S; Kogan, Jennifer R

    2016-02-01

    To address the long-standing challenge of meaningful trainee assessment, the authors reviewed and expanded on the Accountable Assessment for Quality Care and Supervision (AAQCS) equation. The equation proposes that care quality is the product of the interaction between trainee performance (measured by workplace assessment) and supervision (required level of intervention to ensure care quality) in the context of the environment where the care occurs: Trainee performance × Appropriate supervision = Safe, effective patient-centered care. Assessing trainee performance and matching that performance to "appropriate" supervision, however, is fraught with challenges. The authors suggest a unifying framework that integrates entrustable professional activities (EPAs), competencies, and milestones to inform trainee assessment and supervision, thereby enabling the practical application of the AAQCS equation in the workplace. Because the unit of measure for an EPA is the outcome of whether the trainee can safely and effectively perform the professional activity without supervision, the proposed unifying framework directly aligns with the dependent variable in the AAQCS equation: care quality.The value of applying a unifying framework that integrates EPAs, competencies, and milestones to the AAQCS equation in the clinical learning environment lies in its ability to provide supervisors with a shared mental model of performance expectations for trainees, reducing unwanted variability and improving assessment accuracy; guidance for aligning performance milestones of trainees with the needed level of supervisor intervention to ensure care quality; and substrate for specific feedback to improve the trainee's professional development as a way to ensure future care quality. PMID:26509601

  6. Human metapneumovirus infection activates the TSLP pathway that drives excessive pulmonary inflammation and viral replication in mice.

    PubMed

    Lay, Margarita K; Céspedes, Pablo F; Palavecino, Christian E; León, Miguel A; Díaz, Rodrigo A; Salazar, Francisco J; Méndez, Gonzalo P; Bueno, Susan M; Kalergis, Alexis M

    2015-06-01

    Human metapneumovirus (hMPV) is a leading cause of acute respiratory tract infections in children and the elderly. The mechanism by which this virus triggers an inflammatory response still remains unknown. Here, we evaluated whether the thymic stromal lymphopoietin (TSLP) pathway contributes to lung inflammation upon hMPV infection. We found that hMPV infection promotes TSLP expression both in human airway epithelial cells and in the mouse lung. hMPV infection induced lung infiltration of OX40L(+) CD11b(+) DCs. Mice lacking the TSLP receptor deficient mice (tslpr(-/-) ) showed reduced lung inflammation and hMPV replication. These mice displayed a decreased number of neutrophils as well a reduction in levels of thymus and activation-regulated chemokine/CCL17, IL-5, IL-13, and TNF-α in the airways upon hMPV infection. Furthermore, a higher frequency of CD4(+) and CD8(+) T cells was found in tslpr(-/-) mice compared to WT mice, which could contribute to controlling viral spread. Depletion of neutrophils in WT and tslpr(-/-) mice decreased inflammation and hMPV replication. Remarkably, blockage of TSLP or OX40L with specific Abs reduced lung inflammation and viral replication following hMPV challenge in mice. Altogether, these results suggest that activation of the TSLP pathway is pivotal in the development of pulmonary pathology and pulmonary hMPV replication. PMID:25763996

  7. Survival of coliform bacteria in static compost piles of dairy waste solids intended for freestall bedding.

    PubMed

    Mote, C R; Emerton, B L; Allison, J S; Dowlen, H H; Oliver, S P

    1988-06-01

    Dairy waste solids separated from a slurry by a centrifugal separator were composted in 12 static piles. Seven of the compost piles were naturally aerated, and five were aerated by a fan that forced air through the piles of solids. The natural aeration process aged the manure solids in an unconfined pile. The fan in the forced aeration process forced air into a perforated plenum beneath the compost piles. Dairy waste solids in each compost pile were heated into the thermophilic temperature range and generally composted well. At most sampling points, coliform bacteria declined to low or undetectable numbers early in the composting period. However, as the composting process proceeded, bacterial numbers increased to approximately those present in raw dairy waste solids. Findings of this study suggest that composting offers little benefit toward net reduction in coliform bacterial numbers in dairy waste solids. PMID:3403762

  8. Design of passively aerated compost piles: Vertical air velocities between the pipes

    SciTech Connect

    Lynch, N.J.; Cherry, R.S.

    1996-09-01

    Passively aerated compost piles are built on a base of porous materials, such as straw or wood chips, in which perforated air supply pipes are distributed. The piles are not turned during composting, nor is forced-aeration equipment used, which significantly reduces the operating and capital expenses associated with these piles. Currently, pile configurations and materials are worked out by trial and error. Fundamentally based design procedures are difficult to develop because the natural convection air flow rate is not explicitly known, but rather is closely coupled with the pile temperature. This paper develops a mathematical model to analytically determine the maximum upward air flow velocity over an air supply pipe and the drop in vertical velocity away from the pipe. This model has one dimensionless number, dependent on the pile and base properties, which fully characterizes the velocity profile between the pipes. 9 refs., 4 figs., 1 tab.

  9. Tractor Mechanics. Maintaining and Servicing the Power Train, Learning Activity Packages 49-53; Maintaining and Servicing the Clutch, Learning Activity Packages 54-59; Maintaining and Servicing the Transmission and Differential, Learning Activity Packages 60-68; Maintaining and Servicing the Final Drive, Learning Activity Packages 69-77.

    ERIC Educational Resources Information Center

    Clemson Univ., SC. Vocational Education Media Center.

    This series of learning activity packages focuses on four areas of tractor mechanics: (1) maintaining and servicing the power train, (2) maintaining and servicing the clutch, (3) maintaining and servicing the transmission and differential, and (4) maintaining and servicing the final drive. Each of the twenty-nine illustrated learning activity…

  10. Bacterial Community Dynamics in Full-Scale Activated Sludge Bioreactors: Operational and Ecological Factors Driving Community Assembly and Performance

    PubMed Central

    Valentín-Vargas, Alexis; Toro-Labrador, Gladys; Massol-Deyá, Arturo A.

    2012-01-01

    The assembling of bacterial communities in conventional activated sludge (CAS) bioreactors was thought, until recently, to be chaotic and mostly unpredictable. Studies done over the last decade have shown that specific, and often, predictable random and non-random factors could be responsible for that process. These studies have also motivated a “structure–function” paradigm that is yet to be resolved. Thus, elucidating the factors that affect community assembly in the bioreactors is necessary for predicting fluctuations in community structure and function. For this study activated sludge samples were collected during a one-year period from two geographically distant CAS bioreactors of different size. Combining community fingerprinting analysis and operational parameters data with a robust statistical analysis, we aimed to identify relevant links between system performance and bacterial community diversity and dynamics. In addition to revealing a significant β-diversity between the bioreactors’ communities, results showed that the largest bioreactor had a less dynamic but more efficient and diverse bacterial community throughout the study. The statistical analysis also suggests that deterministic factors, as opposed to stochastic factors, may have a bigger impact on the community structure in the largest bioreactor. Furthermore, the community seems to rely mainly on mechanisms of resistance and functional redundancy to maintain functional stability. We suggest that the ecological theories behind the Island Biogeography model and the species-area relationship were appropriate to predict the assembly of bacterial communities in these CAS bioreactors. These results are of great importance for engineers and ecologists as they reveal critical aspects of CAS systems that could be applied towards improving bioreactor design and operation. PMID:22880016

  11. Independent Verification Survey of the Clean Coral Storage Pile at the Johnston Atoll Plutonium Contaminated Soil Remediation Project

    SciTech Connect

    Wilson-Nichols, M.J.; Egidi, P.V.; Roemer, E.K.; Schlosser, R.M.

    2000-09-01

    f I The Oak Ridge National Laboratory (ORNL) Environmental Technology Section conducted an independent verification (IV) survey of the clean storage pile at the Johnston Atoll Plutonium Contaminated Soil Remediation Project (JAPCSRP) from January 18-25, 1999. The goal of the JAPCSRP is to restore a 24-acre area that was contaminated with plutonium oxide particles during nuclear testing in the 1960s. The selected remedy was a soil sorting operation that combined radiological measurements and mining processes to identify and sequester plutonium-contaminated soil. The soil sorter operated from about 1990 to 1998. The remaining clean soil is stored on-site for planned beneficial use on Johnston Island. The clean storage pile currently consists of approximately 120,000 m3 of coral. ORNL conducted the survey according to a Sampling and Analysis Plan, which proposed to provide an IV of the clean pile by collecting a minimum number (99) of samples. The goal was to ascertain wi th 95% confidence whether 97% of the processed soil is less than or equal to the accepted guideline (500-Bq/kg or 13.5-pCi/g) total transuranic (TRU) activity.

  12. Electrical drive for automobile

    SciTech Connect

    Fobbs, H.

    1980-09-16

    Electrical apparatus for driving an automobile is described that is comprised of a dc motor operationally connected to the rear axle through a drive shaft with the motor energized from storage batteries and recharged from alternators coupled to the drive shaft adjacent a clutch at the rear end of the automobile through an auxiliary drive shaft.

  13. Coaxial Redundant Drives

    NASA Technical Reports Server (NTRS)

    Brissette, R.

    1983-01-01

    Harmonic drives allow redundancy and high out put torque in small package. If main drive fails, standby drive takes over and produces torque along same axis as main drive. Uses include power units in robot for internal pipeline inspection, manipulators in deep submersible probes or other applications in which redundancy protects against costly failures.

  14. Exposure to Movie Reckless Driving in Early Adolescence Predicts Reckless, but Not Inattentive Driving

    PubMed Central

    Kostermans, Evelien; Stoolmiller, Mike; de Leeuw, Rebecca N. H.; Engels, Rutger C. M. E.; Sargent, James D.

    2014-01-01

    Objective We examine the association between exposure to depictions of reckless driving in movies and unsafe driving, modeling inattentive and reckless driving as separate outcomes. Methods Data were obtained by telephone from 1,630 US adolescents aged 10 to 14 years at baseline who were drivers at a survey 6 years later. Exposure to movie reckless driving was measured based on movies seen from a randomly selected list of 50 movie titles that had been content coded for reckless driving among characters. Associations were tested with inattentive and reckless driving behaviors in the subsequent survey–controlling for baseline age, sex, socioeconomic status, parental education, school performance, extracurricular activities, daily television and video/computer game exposure, number of movies watched per week, self-regulation and sensation seeking. Results Exposure to movie reckless driving was common, with approximately 10% of movie characters having driven recklessly. Confirmatory factor analysis revealed a significant distinction between items tapping reckless and inattentive driving at the 6th wave. Age and exposure to movie reckless driving at baseline were directly associated with wave-6 reckless (but not inattentive) driving. Additionally, growth in sensation seeking mediated a prospective relation between the total number of movies watched per week at baseline and reckless driving, independent of exposure to movie reckless driving. Males and high sensation seekers reported lower seatbelt usage and more reckless driving, whereas lower self-regulation predicted inattentive driving. Discussion In this study, exposure to movie reckless driving during early adolescence predicted adolescents’ reckless driving, suggesting a direct modeling effect. Other aspects of movies were also associated with reckless driving, with that association mediated through growth in sensation seeking. Predictors of reckless driving were different from predictors of inattentive driving

  15. Avalanches in One-Dimensional Piles with Different Types of Bases

    SciTech Connect

    Altshuler, E.; Ramos, O.; Martinez, C.; Flores, L. E.; Noda, C.

    2001-06-11

    We perform a systematic experimental study of the influence of the type of base on the avalanche dynamics of slowly driven 1D ball piles. The control of base details allows us to explore a wide spectrum of pile structures and dynamics. The scaling properties of the observed avalanche distributions suggest that self-organized critical behavior is approached as the {open_quotes}base-induced{close_quotes} disorder at the pile profile increases.

  16. Vegetation dynamics and its driving forces from climate change and human activities in the Three-River Source Region, China from 1982 to 2012.

    PubMed

    Zhang, Ying; Zhang, Chaobin; Wang, Zhaoqi; Chen, Yizhao; Gang, Chengcheng; An, Ru; Li, Jianlong

    2016-09-01

    The Three-River Source Region (TRSR), a region with key importance to the ecological security of China, has undergone climate changes and a shift in human activities driven by a series of ecological restoration projects in recent decades. To reveal the spatiotemporal dynamics of vegetation dynamics and calculate the contributions of driving factors in the TRSR across different periods from 1982 to 2012, net primary productivity (NPP) estimated using the Carnegie-Ames-Stanford approach model was used to assess the status of vegetation. The actual effects of different climatic variation trends on interannual variation in NPP were analyzed. Furthermore, the relationships of NPP with different climate factors and human activities were analyzed quantitatively. Results showed the following: from 1982 to 2012, the average NPP in the study area was 187.37gcm(-2)yr(-1). The average NPP exhibited a fluctuation but presented a generally increasing trend over the 31-year study period, with an increase rate of 1.31gcm(-2)yr(-2). During the entire study period, the average contributions of temperature, precipitation, and solar radiation to NPP interannual variation over the entire region were 0.58, 0.73, and 0.09gcm(-2)yr(-2), respectively. Radiation was the climate factor with the greatest influence on NPP interannual variation. The factor that restricted NPP increase changed from temperature and radiation to precipitation. The average contributions of climate change and human activities to NPP interannual variation were 1.40gcm(-2)yr(-2) and -0.08gcm(-2)yr(-2), respectively. From 1982 to 2000, the general climate conditions were favorable to vegetation recovery, whereas human activities had a weaker negative impact on vegetation growth. From 2001 to 2012, climate conditions began to have a negative impact on vegetation growth, whereas human activities made a favorable impact on vegetation recovery. PMID:27135584

  17. Numerical simulations of shake-table experiment for dynamic soil-pile-structure interaction in liquefiable soils

    NASA Astrophysics Data System (ADS)

    Tang, Liang; Maula, Baydaa Hussain; Ling, Xianzhang; Su, Lei

    2014-03-01

    A shake-table experiment on pile foundations in liquefiable soils composed of liquefiable sand and overlying soft clay is studied. A three-dimensional (3D) effective stress finite element (FE) analysis is employed to simulate the experiment. A recently developed multi-surface elasto-plastic constitutive model and a fully coupled dynamic inelastic FE formulation ( u- p) are used to model the liquefaction behavior of the sand. The soil domains are discretized using a solid-fl uid fully coupled ( u- p) 20-8 noded brick element. The pile is simulated using beam-column elements. Upon careful calibration, very good agreement is obtained between the computed and the measured dynamic behavior of the ground and the pile. A parametric analysis is also conducted on the model to investigate the effect of pile-pinning, pile diameter, pile stiffness, ground inclination angle, superstructure mass and pile head restraints on the ground improvement. It is found that the pile foundation has a noticeable pinning effect that reduces the lateral soil displacement. It is observed that a larger pile diameter and fixed pile head restraints contribute to decreasing the lateral pile deformation; however, a higher ground inclination angle tends to increase the lateral pile head displacements and pile stiffness, and superstructure mass seems to effectively influence the lateral pile displacements.

  18. Dopaminergic Circuitry Underlying Mating Drive.

    PubMed

    Zhang, Stephen X; Rogulja, Dragana; Crickmore, Michael A

    2016-07-01

    We develop a new system for studying how innate drives are tuned to reflect current physiological needs and capacities, and how they affect sensory-motor processing. We demonstrate the existence of male mating drive in Drosophila, which is transiently and cumulatively reduced as reproductive capacity is depleted by copulations. Dopaminergic activity in the anterior of the superior medial protocerebrum (SMPa) is also transiently and cumulatively reduced in response to matings and serves as a functional neuronal correlate of mating drive. The dopamine signal is transmitted through the D1-like DopR2 receptor to P1 neurons, which also integrate sensory information relevant to the perception of females, and which project to courtship motor centers that initiate and maintain courtship behavior. Mating drive therefore converges with sensory information from the female at the point of transition to motor output, controlling the propensity of a sensory percept to trigger goal-directed behavior. PMID:27292538

  19. PPARα activation drives demethylation of the CpG islands of the Gadd45b promoter in the mouse liver.

    PubMed

    Kim, Jung-Hwan; Wahyudi, Lilik Duwi; Kim, Kee K; Gonzalez, Frank J

    2016-08-01

    Growth arrest and DNA damage-inducible beta (GADD45b) plays a pivotal role in many intracellular events in both cell survival- and cell death-related signaling. To date, the study of GADD35b has mainly focused on investigation of its function, as well as interacting molecules. However, studies of Gadd45b gene regulation are limited. In this study, we investigated the transcriptional regulation mechanism of Gadd45b. Since Gadd45b mRNA is highly induced by the PPARα agonist Wy-14,643 in the mouse liver, we analyzed the Gadd45b promoter using an in vivo reporter assay. Interestingly, the naked Gadd45b-luciferase construct strongly induced luciferase activity without any stimulant in our in vivo system. Therefore, we investigated the epigenetic changes in the Gadd45b promoter region using mouse liver genomic DNA, the methylation-specific restriction enzyme (HpaII), and disulfide conversion. Our results showed that two possible CpG methylation sites were methylated and demethylated by Wy-14,643 treatment. This study indicates that epigenetic change at the Gadd45b promoter is critical for Gadd45b induction. PMID:27233605

  20. Enzyme-ligand interactions that drive active site rearrangements in the Helicobacter pylori 5´-methylthioadenosine/S-adenosylhomocysteine nucleosidase

    SciTech Connect

    Ronning, Donald R; Iacopelli, Natalie M; Mishra, Vidhi

    2012-03-15

    The bacterial enzyme 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase (MTAN) plays a central role in three essential metabolic pathways in bacteria: methionine salvage, purine salvage, and polyamine biosynthesis. Recently, its role in the pathway that leads to the production of autoinducer II, an important component in quorum-sensing, has garnered much interest. Because of this variety of roles, MTAN is an attractive target for developing new classes of inhibitors that influence bacterial virulence and biofilm formation. To gain insight toward the development of new classes of MTAN inhibitors, the interactions between the Helicobacter pylori-encoded MTAN and its substrates and substrate analogs were probed using X-ray crystallography. The structures of MTAN, an MTAN-Formycin A complex, and an adenine bound form were solved by molecular replacement and refined to 1.7, 1.8, and 1.6 Å, respectively. The ribose-binding site in the MTAN and MTAN-adenine cocrystal structures contain a tris[hydroxymethyl]aminomethane molecule that stabilizes the closed form of the enzyme and displaces a nucleophilic water molecule necessary for catalysis. This research gives insight to the interactions between MTAN and bound ligands that promote closing of the enzyme active site and highlights the potential for designing new classes of MTAN inhibitors using a link/grow or ligand assembly development strategy based on the described H. pylori MTAN crystal structures.