SciDAC GSEP: Gyrokinetic Simulation of Energetic Particle Turbulence and Transport
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lin, Zhihong
Energetic particle (EP) confinement is a key physics issue for burning plasma experiment ITER, the crucial next step in the quest for clean and abundant energy, since ignition relies on self-heating by energetic fusion products (α-particles). Due to the strong coupling of EP with burning thermal plasmas, plasma confinement property in the ignition regime is one of the most uncertain factors when extrapolating from existing fusion devices to the ITER tokamak. EP population in current tokamaks are mostly produced by auxiliary heating such as neutral beam injection (NBI) and radio frequency (RF) heating. Remarkable progress in developing comprehensive EP simulationmore » codes and understanding basic EP physics has been made by two concurrent SciDAC EP projects GSEP funded by the Department of Energy (DOE) Office of Fusion Energy Science (OFES), which have successfully established gyrokinetic turbulence simulation as a necessary paradigm shift for studying the EP confinement in burning plasmas. Verification and validation have rapidly advanced through close collaborations between simulation, theory, and experiment. Furthermore, productive collaborations with computational scientists have enabled EP simulation codes to effectively utilize current petascale computers and emerging exascale computers. We review here key physics progress in the GSEP projects regarding verification and validation of gyrokinetic simulations, nonlinear EP physics, EP coupling with thermal plasmas, and reduced EP transport models. Advances in high performance computing through collaborations with computational scientists that enable these large scale electromagnetic simulations are also highlighted. These results have been widely disseminated in numerous peer-reviewed publications including many Phys. Rev. Lett. papers and many invited presentations at prominent fusion conferences such as the biennial International Atomic Energy Agency (IAEA) Fusion Energy Conference and the annual meeting of the American Physics Society, Division of Plasma Physics (APS-DPP).« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gorelenkov, Nikolai N
The area of energetic particle (EP) physics of fusion research has been actively and extensively researched in recent decades. The progress achieved in advancing and understanding EP physics has been substantial since the last comprehensive review on this topic by W.W. Heidbrink and G.J. Sadler [1]. That review coincided with the start of deuterium-tritium (DT) experiments on Tokamak Fusion Test reactor (TFTR) and full scale fusion alphas physics studies. Fusion research in recent years has been influenced by EP physics in many ways including the limitations imposed by the "sea" of Alfven eigenmodes (AE) in particular by the toroidicityinduced AEsmore » (TAE) modes and reversed shear Alfven (RSAE). In present paper we attempt a broad review of EP physics progress in tokamaks and spherical tori since the first DT experiments on TFTR and JET (Joint European Torus) including helical/stellarator devices. Introductory discussions on basic ingredients of EP physics, i.e. particle orbits in STs, fundamental diagnostic techniques of EPs and instabilities, wave particle resonances and others are given to help understanding the advanced topics of EP physics. At the end we cover important and interesting physics issues toward the burning plasma experiments such as ITER (International Thermonuclear Experimental Reactor).« less
NASA Astrophysics Data System (ADS)
Chen, Sile; Wang, Shuai; Wang, Yibo; Guo, Baohong; Li, Guoqiang; Chang, Zhengshi; Zhang, Guan-Jun
2017-08-01
For enhancing the surface electric withstanding strength of insulating materials, epoxy resin (EP) samples are treated by atmospheric pressure plasma jet (APPJ) with different time interval from 0 to 300s. Helium (He) and tetrafluoromethane (CF4) mixtures are used as working gases with the concentration of CF4 ranging 0%-5%, and when CF4 is ∼3%, the APPJ exhibits an optimal steady state. The flashover withstanding characteristics of modified EP in vacuum are greatly improved under appropriate APPJ treatment conditions. The surface properties of EP samples are evaluated by surface roughness, scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and water contact angle. It is considered that both physical and chemical effects lead to the enhancement of flashover strength. The physical effect is reflected in the increase of surface roughness, while the chemical effect is reflected in the graft of fluorine groups.
NIMROD calculations of energetic particle driven toroidal Alfvén eigenmodes
NASA Astrophysics Data System (ADS)
Hou, Yawei; Zhu, Ping; Kim, Charlson C.; Hu, Zhaoqing; Zou, Zhihui; Wang, Zhengxiong; Nimrod Team
2018-01-01
Toroidal Alfvén eigenmodes (TAEs) are gap modes induced by the toroidicity of tokamak plasmas in the absence of continuum damping. They can be excited by energetic particles (EPs) when the EP drive exceeds other dampings, such as electron and ion Landau damping, and collisional and radiative damping. A TAE benchmark case, which was proposed by the International Tokamak Physics Activity group, is studied in this work. The numerical calculations of linear growth of TAEs driven by EPs in a circular-shaped, large aspect ratio tokamak have been performed using the Hybrid Kinetic-MHD (HK-MHD) model implemented in the NIMROD code. This HK-MHD model couples a δf particle-in-cell representation of EPs with the 3D MHD representation of the bulk plasma through moment closure for the momentum conservation equation. Both the excitation of TAEs and their transition to energetic particle modes (EPMs) have been observed. The influence of EP density, temperature, density gradient, and position of the maximum relative density gradient, on the frequency and the growth rate of TAEs are obtained, which are consistent with those from the eigen-analysis calculations, kinetic-MHD, and gyrokinetic simulations for an initial Maxwellian distribution of EPs. The relative pressure gradient of EP at the radial location of the TAE gap, which represents the drive strength of EPs, can strongly affect the growth rate of TAEs. It is demonstrated that the mode transition due to EP drive variation leads to not only the change of frequency but also the change of the mode structure. This mechanism can be helpful in understanding the nonlinear physics of TAE/EPM, such as frequency chirping.
Haberer, Jessica; Celum, Connie; Mugo, Nelly; Ware, Norma C.; Cohen, Craig R.; Tappero, Jordan W.; Kiarie, James; Ronald, Allan; Mujugira, Andrew; Tumwesigye, Elioda; Were, Edwin; Irungu, Elizabeth; Baeten, Jared M.
2016-01-01
Background: Intimate partner violence (IPV) is associated with higher HIV incidence, reduced condom use, and poor adherence to antiretroviral therapy and other medications. IPV may also affect adherence to pre-exposure prophylaxis (PrEP). Methods: We analyzed data from 1785 HIV-uninfected women enrolled in a clinical trial of PrEP among African HIV serodiscordant couples. Experience of verbal, physical, or economic IPV was assessed at monthly visits by face-to-face interviews. Low PrEP adherence was defined as clinic-based pill count coverage <80% or plasma tenofovir levels <40 ng/mL. The association between IPV and low adherence was analyzed using generalized estimating equations, adjusting for potential confounders. In-depth interview transcripts were examined to explain how IPV could impact adherence. Results: Sixteen percent of women reported IPV during a median of 34.8 months of follow-up (interquartile range 27.0–35.0). Overall, 7% of visits had pill count coverage <80%, and 32% had plasma tenofovir <40 ng/mL. Women reporting IPV in the past 3 months had increased risk of low adherence by pill count (adjusted risk ratio 1.49, 95% confidence interval: 1.17 to 1.89) and by plasma tenofovir (adjusted risk ratio 1.51, 95% confidence interval: 1.06 to 2.15). Verbal, economic, and physical IPV were all associated with low adherence. However, the impact of IPV diminished and was not statistically significant 3 months after the reported exposure. In qualitative interviews, women identified several ways in which IPV affected adherence, including stress and forgetting, leaving home without pills, and partners throwing pills away. Conclusions: Women who reported recent IPV in the Partners PrEP Study were at increased risk of low PrEP adherence. Strategies to mitigate PrEP nonadherence in the context of IPV should be evaluated. PMID:27243900
The injection of microorganisms into an atmospheric pressure rf-driven microplasma
NASA Astrophysics Data System (ADS)
Maguire, P. D.; Mahony, C. M. O.; Diver, D.; Mariotti, D.; Bennet, E.; Potts, H.; McDowell, D. A.
2013-09-01
The introduction of living organisms, such as bacteria, into atmospheric pressure microplasmas offers a unique means to study certain physical mechanisms in individual microorganisms and also help understand the impact of macroscopic entities and liquid droplets on plasma characteristics. We present the characterization of an RF-APD operating at 13.56 MHz and containing microorganisms in liquid droplets emitted from a nebulizer, with the spray entrained in a gas flow by a gas shroud and passed into the plasma source. We report successful microorganism injection and transmission through the plasma with stable plasma operation of at least one hour. Diagnostics include RF electrical characterization, optical emission spectrometry and electrostatic deflection to investigate microorganism charging. A close-coupled Impedans Octiv VI probe indicates source efficiencies of 10 to 15%. The introduction of the droplets/microorganisms results in increased plasma conductivity and reduced capacitance, due to their impact on electron density and temperature. An electrical model will be presented based on diagnostic data and deflection studies with input from simulations of charged aerosol diffusion and evaporation. Engineering and Physical Sciences Research Council EP/K006088, EP/K006142.
NASA Astrophysics Data System (ADS)
Mendonça, Tito; Hidalgo, Carlos
2010-12-01
Introduction We are very pleased to present this special issue of Plasma Physics and Controlled Fusion dedicated to another annual EPS Plasma Physics Division Conference. It contains the invited papers of the 37th Conference, which was held at the Helix Arts Centre of the Dublin City University Campus, in Dublin, Ireland, from 21 to 25 June 2010. It was locally organized by a team drawn from different Irish institutions, led by Dublin City University and Queen's University Belfast. This team was coordinated by Professor Miles Turner (DCU), with the help of Dr Deborah O'Connell (QUB) as Scientific Secretary, and Ms Samantha Fahy (DCU) as Submissions Secretary. It attracted a large number of delegates (nearly 750), coming from 37 countries. Our Irish hosts provided an excellent atmosphere for the conference and social programme, very helpful for promoting personal links between conference participants. The Conference hosted three satellite meetings, and two special evening sessions. The satellite meetings were the Third Workshop on Plasma for Environmental Issues, the International Workshop on the Role of Arcing and Hot Spots in Magnetic Fusion Devices, and the Workshop on Electric Fields, Turbulence and Self-Organization in Magnetic Plasmas. The aim of this annual EPS Conference is to bring together the different communities of plasma physicists, in order to stimulate cross-collaboration and to promote in an integrated way this area of science. As in previous Conferences, we tried to attract the more relevant researchers and to present the latest developments in plasma physics and related areas. The Programme Committee was divided into four sub-committees, representing the main areas of plasma science. These four areas were magnetic confinement fusion (MCF), still the dominant area of this Conference with the largest number of participants, beam plasma and inertial fusion (BPIF), low temperature plasmas (LTP), which attracted a significant and growing number of participants, and finally basic and astrophysical plasmas (BAP). New strategies are required to achieve a more balanced participation of these four areas of knowledge in future meetings, but the large number of participants and the overall high quality of the invited talks were particularly relevant this year. In the preparation of the Conference Programme we tried to present an updated view of plasma physics and to integrate suggestions coming from the scientific community, in particular through the use of the EPS PPD Open Forum. As mentioned, two evening sessions took place during the Conference. This year, the traditional evening on ITER was replaced by a session dedicated to inertial fusion, organized by D Batani, where the main installations and experiments on laser fusion around the world were presented and critically discussed. The other session, dedicated to plasma physics education, was organized by N Lopes-Cardoso, and discussed the specific educational issues of plasma physics and fusion, and presented the training programmes existing in Europe. As a concluding remark, we would like to thank our colleagues of the Programme Committee and, in particular, the coordinators of the subcommittees, Clarisse Bourdelle and Arthur Peters for MCF, Javier Honrubia for BPIF, Christoph Hollenstein for LTP, and Uli Stroth for BAP, for their generous help, suggestions and support. Due to the large number of participants, the smooth and efficient local organization, and the high overall quality of the plenary and invited presentations, the 37th EPS Conference on Plasma Physics can be considered an undeniable success. I hope you will find, in this special issue of Plasma Physics and Controlled Fusion, an interesting and useful account of this event. Outstanding scientists honoured at the 37th European Physical Society Conference on Plasma Physics During the Conference the EPS Plasma Physics Division rewarded researchers who have achieved outstanding scientific or technological results. In this way the EPS PPD seeks to reinforce excellence in science. The Plasma Physics Hannes Alfvén Prize 2010 The Hannes Alfvén Prize is awarded to Allen Boozer (Professor, Columbia University) and Jürgen Nührenberg (Professor, Max-Planck-Institut für Plasmaphysik and Greifswald University) for the formulation and practical application of criteria allowing stellarators to have good fast-particle and neoclassical energy confinement. Photo of Boozer and Nuhrenberg Jürgen Nührenberg (left) and Allen Boozer. The tokamak and the stellarator are two major candidate concepts for magnetically confining fusion plasmas. They were both conceived in the early 1950s, but the tokamak developed more rapidly because of its intrinsically favourable confinement properties. Indeed, the stellarator seemed fundamentally unable to confine energy and collisionless alpha-particle orbits well enough for a fusion reactor. In the 1980s, however, Allen Boozer and Jürgen Nührenberg developed methods for tailoring stellarator magnetic fields so as to guarantee confinement comparable to that in tokamaks. Allen Boozer introduced a set of magnetic coordinates, now named after him, in which the description of three-dimensionally shaped magnetic fields is particularly simple. He went on to show that if the magnetic field strength |B| is symmetric in these coordinates (so-called quasisymmetry) then the guiding-centre orbits and the neoclassical confinement properties are equivalent to those in a tokamak. In pioneering calculations a few years later, Jürgen Nührenberg showed that such magnetic fields can indeed be realized in practice, as can other configurations which have equally good confinement without being quasisymmetric. There is an unexpected vastness of configurational possibilities for toroidal plasma confinement, where the limit is likely to be set by turbulence rather than neoclassical losses. In addition, quasisymmetry should facilitate the development of strongly sheared rotation with direct impact in the control of turbulent transport. Moreover, Jügen Nührenberg showed that a number of other properties of the magnetic field can also be optimized simultaneously, allowing high equilibrium and stability limits to be achieved and thus opening up a route to an inherently steady-state fusion reactor. The ideas of Allen Boozer and Jürgen Nührenberg have revolutionized stellarator research. They have already partially been confirmed on the W7-AS and HSX stellarators, and provide the basis for the world's largest stellarator under construction, Wendelstein 7-X. The award of the 2010 Hannes Alfvén Prize to these two leading scientists underlines the development of understanding and transfer of knowledge in plasma physics. Invited papers by Allen Boozer and Jürgen Nührenberg are published as articles 124002 and 124003 in this special issue of Plasma Physics and Controlled Fusion. The Plasma Physics Innovation Prize 2010 The 2010 Plasma Physics Innovation Prize of the European Physical Society is awarded to Uwe Czarnetzki (Professor, Ruhr-Universität Bochum) for his outstanding contributions in the discovery of the electrical asymmetry effect, its scientific characterization and for its development up to the level of successful industrial application. photo of Uwe Czarnetzki Uwe Czarnetzki. The energy of ions impacting surfaces during plasma processing is crucial in determining both the properties of materials being deposited by plasmas and for the control of the etching of thin films. The independent control of the ion energy and the plasma density has been the object of intense industrial research. Current technologies for modifying the ion energy rely on the geometry of the plasma processing chamber or on applying low and high frequency RF power that is not phase locked. These techniques are either not applicable to some situations or have only been partially successful. The electrical asymmetry effect allows the ion energy and plasma density to be decoupled. If the RF power applied to a plasma chamber is comprised of a phase locked fundamental and its second harmonic, the ion energy is a linear function of the phase angle between the two. This simple but previously overlooked technique has proved to be an enabling technology for future materials and plasma applications. The method has been patented and is currently used, for example, by leading manufacturers of large area solar cells and has resulted in unsurpassed quality and homogeneity of the devices. In addition to the elctrical asymmetry effect, Uwe Czarnetzki is internationally renowned for his many important contributions in the areas of laser-based plasma diagnostics and gas discharge physics. For all of these outstanding contributions to low temperature plasmas, the European Physical Society bestows its 2010 Plasma Physics Innovation Prize on Uwe Czarnetzki. The PhD Research Award 2010 The Plasma Physics Division 2010 PhD Research Award has been judged by a committee comprising Juergen Meyer-ter-Vehn, Emmanuel Marode and Michel Chatelier who examined all the candidatures in a process managed by Dimitri Batani. The EPS PhD prize is a key element of the EPS PPD activities to recognize exceptional quality of the work carried out by young physicists. photo of PhD Award winners The 2010 PhD Research Award winners. From left to right: Emeric Falize, Guilhem Dif-Pradalier, Bérénice Loupias, Peter Manz and Xavier Davoine. The jury nominated four award winners from a pool of impressively high quality candidates. The 2010 citations in alphabetical order are: Xavier Davoine for his research on an intense ultra short X source obtained by acceleration of a class of electrons in the wakefield of a laser pulse, improving the numerical procedure to model the electron dynamics. Guilhem Dif-Pradalier for a fundamental discussion of the formalism needed to describe turbulence and transport in magnetized plasmas, including a collision operator in the Gysela gyrokinetic code that could modify the characteristics of the turbulence. Emeric Falize and Bérénice Loupias for their investigation of similarities between laser-induced plasmas and astrophysical systems and for the description of a set of diagnostics for laser plasmas aimed at demonstrating the possible astrophysics character of plasma jets in laser-induced plasma formation. Peter Manz for his comprehensive analysis of turbulence in magnetized plasmas, exploring the interplay between flows, electric fields and fluctuations. Itoh Project Prize in Plasma Turbulence 2010 Professor Sanae Itoh from Kyushu University continued to sponsor the Itoh Project Prize in Plasma Turbulence. The 2010 prize was awarded to G Birkenmeier (Stuttgart University). IOP Poster Prize winners in Dublin, 2010. The Institute of Physics (IOP) has once again provided encouragement for young physiscs with the IOP Poster Prize. Caroline Wilkinson presented the awards this year to three candidates: Mattia Albergante (EPFL, Lausanne), Clelia Pagano (Trinity College Dublin) and Marija Vranic (Instituto Superior Tecnico, Lisbon). Proceedings of 37th EPS Conference on Plasma Physics As previously mentioned, this special issue contains the invited papers of the 37th Conference, held in 2010. The complete proceedings are available online at http://ocs.ciemat.es/EPS2010PAP/html/ This site is also accessible from the conference website at http://www.eps2010.com/ (under `Contributions'). The Local Organizing Committee has also prepared a CD with a copy of the proceedings, identical to the online proceedings. This CD is stored at the offices of the European Physical Society as a backup, and as a master copy to make additional copies in case anyone should require one.
Plasma - enhanced dispersion of metal and ceramic nanoparticles in polymer nanocomposite films
NASA Astrophysics Data System (ADS)
Maguire, Paul; Liu, Yazi; Askari, Sadegh; Patel, Jenish; Macia-Montero, Manuel; Mitra, Somak; Zhang, Richao; Sun, Dan; Mariotti, Davide
2015-09-01
In this work we demonstrate a facile method to synthesize a nanoparticle/PEDOT:PSS hybrid nanocomposite material in aqueous solution through atmospheric pressure direct current (DC) plasma processing at room temperature. Both metal (Au) and ceramic (TiO2) nanoparticle composite films have been fabricated. Nanoparticle dispersion is enhanced considerable and remains stable. TiO2/polymer hybrid nanoparticles with a distinct core shell structure have been obtained. Increased nanoparticle/PEDOT:PSS nanocomposite electrical conductivity has been observed. The improvement in nanocomposite properties is due to the enhanced dispersion and stability in liquid polymer of microplasma processed Au or TiO2 nanoparticles. Both plasma induced surface charge and nanoparticle surface termination with specific plasma chemical species are thought to provide an enhanced barrier to nanoparticle agglomeration and promote nanoparticle-polymer bonding. This is expected to have a significant benefit in materials processing with inorganic nanoparticles for applications in energy storage, photocatalysis and biomedical sensors. Engineering and Physical Sciences Research Council (EPSRC: EP/K006088/1, EP/K006142, Nos. EP/K022237/1).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Decoste, R.; Lachambre, J.; Abel, G.
1994-05-01
Electrically insulated divertor plates are used on TdeV (Tokamak de Varennes) [18[ital th] [ital EPS] [ital Conference] [ital on] [ital Controlled] [ital Fusion] [ital and] [ital Plasma] [ital Physics] Berlin (European Physical Society, Petit-Lancy, 1991), Vol. 15C, Part I, pp. 1--141] to produce various biasing configurations, which can be decomposed into two basic modes. Plasma biasing, with a radial electric field [ital E][sub [ital r
Feng, Shao-Dan; Jiang, Yong; Lin, Zhi-Hong; Lin, Pei-Hong; Lin, Si-Ming; Liu, Qi-Cai
2017-08-01
This study aims to evaluate the diagnostic value of beta-endorphin (β-EP) and brain natriuretic peptid (BNP) plasma concentrations for the early diagnosis of acute left heart failure and atrial fibrillation. A total of 45 patients were included. These patients comprised 23 male and 22 female patients,and 20 healthy subjects who underwent physical examinations in the Outpatient Department during the same periodwere included and assigned to the control group. The diagnos stand was that of the Chinese guidelines for the diagnosis and treatment of heart failure. Enzyme-linked immunosorbent assay was performed to detect the plasma concentration of β-EP and BNP in the treatment and control groups, and electrocardiogram targeting was performed to determine the left ventricular ejection fraction (LVEF). BNP, β-EP, and LVEF levels were higher in the treatment group (688.01 ± 305.78 ng/L, 394.06 ± 180.97 ng/L, and 70.48 ± 16.62%) compared with the control group (33.90 ± 8.50 ng/L, 76.87 ± 57.21 ng/L, and 32.11 ± 5.25%). The P-values were .015, .019, and .026, respectively, which were <.05. The difference was statistically significant. The BNP and β-EP's 4 correlations (r = 0.895, P <.001), BNP, β-EP, and the combination of BNP and β-EP for acute left heart failure diagnosis in maximizing Youden index sensitivity, specific degree, area under the ROC curve (AUC), and 95% confidence interval (CI) were respectively 93.5%, 81.3%, 0.921, 0.841, 0.921; 80.5%, 78.6%, 0.697, 0.505, 0.697; 94.1%, 83.5%, 0.604 to 0.979, and 0.604. Acute left heart failure in patients with LVEF acuity plasma BNP and β-EP 50% group was obviously lower than that in the LVEF <50% group (P <.01). BNP, β-EP, and LVEF were negatively correlated (r = -0.741, -0.635, P = .013, .018). β-EP and BNP have high specificity and sensitivity for detecting early acute left heart failure and atrial fibrillation in patients, which is convenient, easy to perform, and suitable for clinical applications.
Theory and Numerical Simulation of Plasma-wall Interactions in Electric Propulsion
NASA Astrophysics Data System (ADS)
Mikellides, Ioannis
2016-10-01
Electric propulsion (EP) can be an enabling technology for many science missions considered by NASA because it can produce high exhaust velocities, which allow for less propellant mass compared to typical chemical systems. Over the last decade two EP technologies have emerged as primary candidates for several proposed science missions, mainly due to their superior performance and proven record in space flight: the Ion and Hall thrusters. As NASA looks ahead to increasingly ambitious science goals, missions demand higher endurance from the propulsion system. So, by contrast to the early years of development of these thrusters, when the focus was on performance, considerable focus today is shifting towards extending their service life. Considering all potentially life-limiting mechanisms in Ion and Hall thrusters two are of primary concern: (a) the erosion of the acceleration channel in Hall thrusters and (b) the erosion of the hollow cathode. The plasma physics leading to material wear in these devices are uniquely challenging. For example, soon after the propellant is introduced into the hollow cathode it becomes partially ionized as it traverses a region of electron emission. Electron emission involves highly non-linear boundary conditions. Also, the sheath size is typically many times smaller than the characteristic physical scale of the device, yet energy gained by ions through the sheath must be accounted for in the erosion calculations. The plasma-material interactions in Hall thruster channels pose similar challenges that are further exacerbated by the presence of a strong applied magnetic field. In this presentation several complexities associated with plasma-wall interactions in EP will be discussed and numerical simulation results of key plasma properties in two examples, Hall thrusters and hollow cathodes, will be presented.
Initial Ferritic Wall Mode studies on HBT-EP
NASA Astrophysics Data System (ADS)
Hughes, Paul; Bialek, J.; Boozer, A.; Mauel, M. E.; Levesque, J. P.; Navratil, G. A.
2013-10-01
Low-activation ferritic steels are leading material candidates for use in next-generation fusion development experiments such as a prospective US component test facility and DEMO. Understanding the interaction of plasmas with a ferromagnetic wall will provide crucial physics for these experiments. Although the ferritic wall mode (FWM) was seen in a linear machine, the FWM was not observed in JFT-2M, probably due to eddy current stabilization. Using its high-resolution magnetic diagnostics and positionable walls, HBT-EP has begun exploring the dynamics and stability of plasma interacting with high-permeability ferritic materials tiled to reduce eddy currents. We summarize a simple model for plasma-wall interaction in the presence of ferromagnetic material, describe the design of a recently-installed set of ferritic shell segments, and report initial results. Supported by U.S. DOE Grant DE-FG02-86ER53222.
Ibey, Bennett L.; Xiao, Shu; Schoenbach, Karl H.; Murphy, Michael R.; Pakhomov, Andrei G.
2008-01-01
We explored how the effect of plasma membrane permeabilization by nanosecond-duration electric pulses (nsEP) depends on the physical characteristics of exposure. The resting membrane resistance (Rm) and membrane potential (MP) were measured in cultured GH3 and CHO cells by conventional whole-cell patch-clamp technique. Intact cells were exposed to a single nsEP (60 or 600 ns duration, 0-22 kV/cm), followed by patch-clamp measurements after a 2-3 min delay. Consistent with earlier findings, nsEP caused long-lasting Rm decrease, accompanied by the loss of MP. The threshold for these effects was about 6 kV/cm for 60 ns pulses, and about 1 kV/cm for 600 ns pulses. Further analysis established that it was neither pulse duration nor the E-field amplitude per se, but the absorbed dose that determined the magnitude of the biological effect. In other words, exposure to nsEP at either pulse duration caused equal effects if the absorbed doses were equal. The threshold absorbed dose to produce plasma membrane effects in either GH3 or CHO cells at either pulse duration was found to be at or below 10 mJ/g. Despite being determined by the dose, the nsEP effect clearly is not thermal, as the maximum heating at the threshold dose is less than 0.01 °C. The use of the absorbed dose as a universal exposure metric may help to compare and quantify nsEP sensitivity of different cell types and of cells in different physiological conditions. The absorbed dose may also prove to be a more useful metric than the incident E-field in determining safety limits for high peak, lowaverage power EMF emissions. PMID:18839412
Fast Ion Transport Studies in DIII-D High βN Steady-State Scenarios
NASA Astrophysics Data System (ADS)
Holcomb, C. T.
2014-10-01
DIII-D research is identifying paths to optimize energetic particle (EP) transport in high βN steady-state tokamak scenarios. Operation with qmin > 2 is predicted to achieve high βN, confinement, and bootstrap fraction. However DIII-D experiments have shown that Alfvén eigenmodes (AE) and correlated EP transport can limit the performance of some qmin > 2 plasmas. Enhanced EP transport occurs in plasmas with qmin = 2-2.5, q95 = 5-7, and relatively long slowing down time. Strong AEs are present, the confinement factor H89 = 1.6-1.8 and βN is limited to ~3 by the available power. These observations are consistent with EP transport models having a critical gradient in βf. However, adjusting the parameters can recover classical EP confinement or improve thermal confinement so that H89 > 2 . One example is a scenario with βP and βN ~ 3 . 2 , qmin > 3 and q95 ~ 11 developed to test control of long pulse, high heat flux operation on devices like EAST. This has an internal transport barrier at ρ ~ 0 . 7 , bootstrap fraction >75%, density limit fraction ~1, and H89 >= 2 . In these cases AE activity and EP transport is very dynamic - it varies between classical and anomalous from shot to shot and within shots. Thus these plasmas are close to a threshold for enhanced EP transport. This may be governed by a combination of a relatively low ∇βfast due to good thermal confinement and lower beam power, short slowing down time, and possibly changes to the q-profile. Another example is scenarios with qmin ~ 1.1. These typically have classical EP confinement and good thermal confinement. Thus by using its flexible parameters and profile control tools DIII-D is comparing a wide range of steady-state scenarios to identify the key physics setting EP transport. Work supported by the US Department of Energy under DE-AC52-07NA27344, SC-G903402, DE-FC02-04ER54698, and DE-AC02-09CH11466.
NASA Astrophysics Data System (ADS)
Yang, S. X.; Hao, G. Z.; Liu, Y. Q.; Wang, Z. X.; Hu, Y. J.; Zhu, J. X.; He, H. D.; Wang, A. K.
2018-04-01
The toroidal Alfvén eigenmode (TAE), excited by trapped energetic particles (EPs), is numerically investigated in a tokamak plasma, using the non-perturbative magnetohydrodynamic-kinetic hybrid formulation based MARS-K code (Liu et al 2008 Phys. Plasmas 15 112503). Compared with the fixed boundary condition at the plasma edge, a free boundary enhances the critical value of the EPs kinetic contribution for driving the TAE. Free boundary also induces finite perturbations at the plasma edge as expected. An anisotropic distribution of EPs, in the particle pitch angle space, strongly enhances the instability and results in a more global mode structure, compared with the isotropic case. The plasma resistivity is also found to play a role in the EPs-destabilized TAE. In particular, the mode stability domain is mapped out, in the 2D parameter space of the plasma resistivity and a quantity defining the width of the particle distribution in pitch angle (for anisotropic distribution). A resonance layer in the poloidal mode structure, with the layer width increasing with the plasma resistivity, appears at the large width of the particle distribution in pitch angle space. A mode conversion, from the modified ideal kink by the EPs kinetic effect to the TAE, is also observed while increasing the birth energy of EPs. Computational results suggest that the TAE mode structure can be modified by certain key plasma parameters, such as the EPs kinetic contribution, the equilibrium pressure, the plasma resistivity, the distribution of EPs, as well as the birth energy of EPs. Such modification of the eigenmode structure can only be obtained following the non-perturbative hybrid approach (Wang et al 2013 Phys. Rev. Lett. 111 145003, Wang et al 2015 Phys. Plasmas 22 022509), as adopted in this study. More importantly, numerical results show that near the marginal stability point, the dominant poloidal harmonics of the TAE overlap with each other, and are localized at the tip positions of the Alfvén continua. This kind of TAE structure in high beta plasma with unstable ideal kink is substantially different from that of the conventional TAE.
Specific radioimmunoassay of human. beta. -endorphin in unextracted plasma
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wiedemann, E.; Saito, T.; Linfoot, J.A.
1979-09-01
With an antiserum against human ..beta..-endorphin (..beta..-EP) crossreacting <2% with human ..beta..-lipotropin (..beta..-LPH) by weight we have developed a radioimmunoassay that can detect 1 pg ..beta..-EP in diluted raw plasma. In a.m. fasting plasma of 14 normal subjects ..beta..-EP ranged from <5 to 45 pg/ml. ..beta..-EP was elevated in untreated, but normal in successfully treated Cushing's disease; undetectable in a patient with adrenal adenoma; extremely high in Nelson's syndrome; and elevated in a patient with bronchogenic carcinoma before, but undetectable after tumor resection. In subjects with intact hypothalamic-pituitary-adrenal axis, ..beta..-EP was undectectable after dexamethasone and increased after metyrapone administration andmore » insulin-induced hypoglycemia. ..beta..-EP concentration was considerably lower in serum than in simultaneously collected plasma, but increased in serum left unfrozen for several hours after clot removal. Thus, ..beta..-EP behaves like a hormone responding to the same stimuli as ACTH and ..beta..-LPH and blood appears to contain enzymes both generating and destroying immunoreactive ..beta..-EP.« less
Effects of energetic particle phase space modifications by instabilities on integrated modeling
NASA Astrophysics Data System (ADS)
Podestà, M.; Gorelenkova, M.; Fredrickson, E. D.; Gorelenkov, N. N.; White, R. B.
2016-11-01
Tokamak plasmas can feature a large population of energetic particles (EP) from neutral beam injection or fusion reactions. In turn, energetic particles can drive instabilities, which affect the driving EP population leading to a distortion of the original EP distribution function and of quantities that depend on it. The latter include, for example, neutral beam (NB) current drive and plasma heating through EP thermalization. Those effects must be taken into account to enable reliable and quantitative simulations of discharges for present devices as well as predictions for future burning plasmas. Reduced models for EP transport are emerging as an effective tool for long time-scale integrated simulations of tokamak plasmas, possibly including the effects of instabilities on EP dynamics. Available models differ in how EP distribution properties are modified by instabilities, e.g. in terms of gradients in real or phase space. It is therefore crucial to assess to what extent different assumptions in the transport models affect predicted quantities such as EP profile, energy distribution, NB driven current and energy/momentum transfer to the thermal populations. A newly developed kick model, which includes modifications of the EP distribution by instabilities in both real and velocity space, is used in this work to investigate these issues. Coupled to TRANSP simulations, the kick model is used to analyze NB-heated NSTX and DIII-D discharges featuring unstable Alfvén eigenmodes (AEs). Results show that instabilities can strongly affect the EP distribution function, and modifications propagate to macroscopic quantities such as NB-driven current profile and NB power transferred to the thermal plasma species. Those important aspects are only qualitatively captured by simpler fast ion transport models that are based on radial diffusion of energetic ions only.
Effects of energetic particle phase space modifications by instabilities on integrated modeling
Podesta, M.; Gorelenkova, M.; Fredrickson, E. D.; ...
2016-07-22
Tokamak plasmas can feature a large population of energetic particles (EP) from neutral beam injection or fusion reactions. In turn, energetic particles can drive instabilities, which affect the driving EP population leading to a distortion of the original EP distribution function and of quantities that depend on it. The latter include, for example, neutral beam (NB) current drive and plasma heating through EP thermalization. Those effects must be taken into account to enable reliable and quantitative simulations of discharges for present devices as well as predictions for future burning plasmas. Reduced models for EP transport are emerging as an effectivemore » tool for long time-scale integrated simulations of tokamak plasmas, possibly including the effects of instabilities on EP dynamics. Available models differ in how EP distribution properties are modified by instabilities, e.g. in terms of gradients in real or phase space. It is therefore crucial to assess to what extent different assumptions in the transport models affect predicted quantities such as EP profile, energy distribution, NB driven current and energy/momentum transfer to the thermal populations. A newly developed kick model, which includes modifications of the EP distribution by instabilities in both real and velocity space, is used in this work to investigate these issues. Coupled to TRANSP simulations, the kick model is used to analyze NB-heated NSTX and DIII-D discharges featuring unstable Alfvén eigenmodes (AEs). Results show that instabilities can strongly affect the EP distribution function, and modifications propagate to macroscopic quantities such as NB-driven current profile and NB power transferred to the thermal plasma species. Furthermore, those important aspects are only qualitatively captured by simpler fast ion transport models that are based on radial diffusion of energetic ions only.« less
Off-axis fishbone-like instability and excitation of resistive wall modes in JT-60U and DIII-D
DOE Office of Scientific and Technical Information (OSTI.GOV)
Okabayashi, M.; Solomon, W. M.; Budny, R. V.
2011-05-15
An energetic-particle (EP)-driven ''off-axis-fishbone-like mode (OFM)'' often triggers a resistive wall mode (RWM) in JT-60U and DIII-D devices, preventing long-duration high-{beta}{sub N} discharges. In these experiments, the EPs are energetic ions (70-85 keV) injected by neutral beams to produce high-pressure plasmas. EP-driven bursting events reduce the EP density and the plasma rotation simultaneously. These changes are significant in high-{beta}{sub N} low-rotation plasmas, where the RWM stability is predicted to be strongly influenced by the EP precession drift resonance and by the plasma rotation near the q=2 surface (kinetic effects). Analysis of these effects on stability with a self-consistent perturbation tomore » the mode structure using the MARS-K code showed that the impact of EP losses and rotation drop is sufficient to destabilize the RWM in low-rotation plasmas, when the plasma rotation normalized by Alfven frequency is only a few tenths of a percent near the q=2 surface. The OFM characteristics are very similar in JT-60U and DIII-D, including nonlinear mode evolution. The modes grow initially like a classical fishbone, and then the mode structure becomes strongly distorted. The dynamic response of the OFM to an applied n=1 external field indicates that the mode retains its external kink character. These comparative studies suggest that an energetic particle-driven 'off-axis-fishbone-like mode' is a new EP-driven branch of the external kink mode in wall-stabilized plasmas, analogous to the relationship of the classical fishbone branch to the internal kink mode.« less
Johansson, Jenny U; Pradhan, Suraj; Lokteva, Ludmila A; Woodling, Nathaniel S; Ko, Novie; Brown, Holden D; Wang, Qian; Loh, Christina; Cekanaviciute, Egle; Buckwalter, Marion; Manning-Bog, Amy B; Andreasson, Katrin I
2013-10-02
Prostaglandin E2 (PGE2), a potent lipid signaling molecule, modulates inflammatory responses through activation of downstream G-protein coupled EP(1-4) receptors. Here, we investigated the cell-specific in vivo function of PGE2 signaling through its E-prostanoid 2 (EP2) receptor in murine innate immune responses systemically and in the CNS. In vivo, systemic administration of lipopolysaccharide (LPS) resulted in a broad induction of cytokines and chemokines in plasma that was significantly attenuated in EP2-deficient mice. Ex vivo stimulation of peritoneal macrophages with LPS elicited proinflammatory responses that were dependent on EP2 signaling and that overlapped with in vivo plasma findings, suggesting that myeloid-lineage EP2 signaling is a major effector of innate immune responses. Conditional deletion of the EP2 receptor in myeloid lineage cells in Cd11bCre;EP2(lox/lox) mice attenuated plasma inflammatory responses and transmission of systemic inflammation to the brain was inhibited, with decreased hippocampal inflammatory gene expression and cerebral cortical levels of IL-6. Conditional deletion of EP2 significantly blunted microglial and astrocytic inflammatory responses to the neurotoxin MPTP and reduced striatal dopamine turnover. Suppression of microglial EP2 signaling also increased numbers of dopaminergic (DA) neurons in the substantia nigra independent of MPTP treatment, suggesting that microglial EP2 may influence development or survival of DA neurons. Unbiased microarray analysis of microglia isolated from adult Cd11bCre;EP2(lox/lox) and control mice demonstrated a broad downregulation of inflammatory pathways with ablation of microglial EP2 receptor. Together, these data identify a cell-specific proinflammatory role for macrophage/microglial EP2 signaling in innate immune responses systemically and in brain.
Johansson, Jenny U.; Pradhan, Suraj; Lokteva, Ludmila A.; Woodling, Nathaniel S.; Ko, Novie; Brown, Holden D.; Wang, Qian; Loh, Christina; Cekanaviciute, Egle; Buckwalter, Marion; Manning-Boğ, Amy B.
2013-01-01
Prostaglandin E2 (PGE2), a potent lipid signaling molecule, modulates inflammatory responses through activation of downstream G-protein coupled EP1–4 receptors. Here, we investigated the cell-specific in vivo function of PGE2 signaling through its E-prostanoid 2 (EP2) receptor in murine innate immune responses systemically and in the CNS. In vivo, systemic administration of lipopolysaccharide (LPS) resulted in a broad induction of cytokines and chemokines in plasma that was significantly attenuated in EP2-deficient mice. Ex vivo stimulation of peritoneal macrophages with LPS elicited proinflammatory responses that were dependent on EP2 signaling and that overlapped with in vivo plasma findings, suggesting that myeloid-lineage EP2 signaling is a major effector of innate immune responses. Conditional deletion of the EP2 receptor in myeloid lineage cells in Cd11bCre;EP2lox/lox mice attenuated plasma inflammatory responses and transmission of systemic inflammation to the brain was inhibited, with decreased hippocampal inflammatory gene expression and cerebral cortical levels of IL-6. Conditional deletion of EP2 significantly blunted microglial and astrocytic inflammatory responses to the neurotoxin MPTP and reduced striatal dopamine turnover. Suppression of microglial EP2 signaling also increased numbers of dopaminergic (DA) neurons in the substantia nigra independent of MPTP treatment, suggesting that microglial EP2 may influence development or survival of DA neurons. Unbiased microarray analysis of microglia isolated from adult Cd11bCre;EP2lox/lox and control mice demonstrated a broad downregulation of inflammatory pathways with ablation of microglial EP2 receptor. Together, these data identify a cell-specific proinflammatory role for macrophage/microglial EP2 signaling in innate immune responses systemically and in brain. PMID:24089506
Phase space effects on fast ion distribution function modeling in tokamaks
NASA Astrophysics Data System (ADS)
Podestà, M.; Gorelenkova, M.; Fredrickson, E. D.; Gorelenkov, N. N.; White, R. B.
2016-05-01
Integrated simulations of tokamak discharges typically rely on classical physics to model energetic particle (EP) dynamics. However, there are numerous cases in which energetic particles can suffer additional transport that is not classical in nature. Examples include transport by applied 3D magnetic perturbations and, more notably, by plasma instabilities. Focusing on the effects of instabilities, ad-hoc models can empirically reproduce increased transport, but the choice of transport coefficients is usually somehow arbitrary. New approaches based on physics-based reduced models are being developed to address those issues in a simplified way, while retaining a more correct treatment of resonant wave-particle interactions. The kick model implemented in the tokamak transport code TRANSP is an example of such reduced models. It includes modifications of the EP distribution by instabilities in real and velocity space, retaining correlations between transport in energy and space typical of resonant EP transport. The relevance of EP phase space modifications by instabilities is first discussed in terms of predicted fast ion distribution. Results are compared with those from a simple, ad-hoc diffusive model. It is then shown that the phase-space resolved model can also provide additional insight into important issues such as internal consistency of the simulations and mode stability through the analysis of the power exchanged between energetic particles and the instabilities.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Podesta, M.; Gorelenkova, M.; Fredrickson, E. D.
Here, integrated simulations of tokamak discharges typically rely on classical physics to model energetic particle (EP) dynamics. However, there are numerous cases in which energetic particles can suffer additional transport that is not classical in nature. Examples include transport by applied 3D magnetic perturbations and, more notably, by plasma instabilities. Focusing on the effects of instabilities,ad-hocmodels can empirically reproduce increased transport, but the choice of transport coefficients is usually somehow arbitrary. New approaches based on physics-based reduced models are being developed to address those issues in a simplified way, while retaining a more correct treatment of resonant wave-particle interactions. Themore » kick model implemented in the tokamaktransport code TRANSP is an example of such reduced models. It includes modifications of the EP distribution by instabilities in real and velocity space, retaining correlations between transport in energy and space typical of resonant EP transport. The relevance of EP phase space modifications by instabilities is first discussed in terms of predicted fast ion distribution. Results are compared with those from a simple, ad-hoc diffusive model. It is then shown that the phase-space resolved model can also provide additional insight into important issues such as internal consistency of the simulations and mode stability through the analysis of the power exchanged between energetic particles and the instabilities.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Podestà, M., E-mail: mpodesta@pppl.gov; Gorelenkova, M.; Fredrickson, E. D.
Integrated simulations of tokamak discharges typically rely on classical physics to model energetic particle (EP) dynamics. However, there are numerous cases in which energetic particles can suffer additional transport that is not classical in nature. Examples include transport by applied 3D magnetic perturbations and, more notably, by plasma instabilities. Focusing on the effects of instabilities, ad-hoc models can empirically reproduce increased transport, but the choice of transport coefficients is usually somehow arbitrary. New approaches based on physics-based reduced models are being developed to address those issues in a simplified way, while retaining a more correct treatment of resonant wave-particle interactions.more » The kick model implemented in the tokamak transport code TRANSP is an example of such reduced models. It includes modifications of the EP distribution by instabilities in real and velocity space, retaining correlations between transport in energy and space typical of resonant EP transport. The relevance of EP phase space modifications by instabilities is first discussed in terms of predicted fast ion distribution. Results are compared with those from a simple, ad-hoc diffusive model. It is then shown that the phase-space resolved model can also provide additional insight into important issues such as internal consistency of the simulations and mode stability through the analysis of the power exchanged between energetic particles and the instabilities.« less
Phase space effects on fast ion distribution function modeling in tokamaks
White, R. B. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Podesta, M. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Gorelenkova, M. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Fredrickson, E. D. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Gorelenkov, N. N. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
2016-06-01
Integrated simulations of tokamak discharges typically rely on classical physics to model energetic particle (EP) dynamics. However, there are numerous cases in which energetic particles can suffer additional transport that is not classical in nature. Examples include transport by applied 3D magnetic perturbations and, more notably, by plasma instabilities. Focusing on the effects of instabilities, ad-hoc models can empirically reproduce increased transport, but the choice of transport coefficients is usually somehow arbitrary. New approaches based on physics-based reduced models are being developed to address those issues in a simplified way, while retaining a more correct treatment of resonant wave-particle interactions. The kick model implemented in the tokamak transport code TRANSP is an example of such reduced models. It includes modifications of the EP distribution by instabilities in real and velocity space, retaining correlations between transport in energy and space typical of resonant EP transport. The relevance of EP phase space modifications by instabilities is first discussed in terms of predicted fast ion distribution. Results are compared with those from a simple, ad-hoc diffusive model. It is then shown that the phase-space resolved model can also provide additional insight into important issues such as internal consistency of the simulations and mode stability through the analysis of the power exchanged between energetic particles and the instabilities.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ghorbanalilu, M.; Physics Department, Azarbaijan Shahid Madani University, Tabriz; Sadegzadeh, S.
2014-05-15
The existence of Weibel instability for a streaming electron, counterstreaming electron-electron (e-e), and electron-positron (e-p) plasmas with intrinsic temperature anisotropy is investigated. The temperature anisotropy is included in the directions perpendicular and parallel to the streaming direction. It is shown that the beam mean speed changes the instability mode, for a streaming electron beam, from the classic Weibel to the Weibel-like mode. The analytical and numerical solutions approved that Weibel-like modes are excited for both counterstreaming e-e and e-p plasmas. The growth rates of the instabilities in e-e and e-p plasmas are compared. The growth rate is larger for e-pmore » plasmas if the thermal anisotropy is small and the opposite is true for large thermal anisotropies. The analytical and numerical solutions are in good agreement only in the small parallel temperature and wave number limits, when the instability growth rate increases linearly with normalized wave number kc∕ω{sub p}.« less
PIXIE3D: A Parallel, Implicit, eXtended MHD 3D Code
NASA Astrophysics Data System (ADS)
Chacon, Luis
2006-10-01
We report on the development of PIXIE3D, a 3D parallel, fully implicit Newton-Krylov extended MHD code in general curvilinear geometry. PIXIE3D employs a second-order, finite-volume-based spatial discretization that satisfies remarkable properties such as being conservative, solenoidal in the magnetic field to machine precision, non-dissipative, and linearly and nonlinearly stable in the absence of physical dissipation. PIXIE3D employs fully-implicit Newton-Krylov methods for the time advance. Currently, second-order implicit schemes such as Crank-Nicolson and BDF2 (2^nd order backward differentiation formula) are available. PIXIE3D is fully parallel (employs PETSc for parallelism), and exhibits excellent parallel scalability. A parallel, scalable, MG preconditioning strategy, based on physics-based preconditioning ideas, has been developed for resistive MHD, and is currently being extended to Hall MHD. In this poster, we will report on progress in the algorithmic formulation for extended MHD, as well as the the serial and parallel performance of PIXIE3D in a variety of problems and geometries. L. Chac'on, Comput. Phys. Comm., 163 (3), 143-171 (2004) L. Chac'on et al., J. Comput. Phys. 178 (1), 15- 36 (2002); J. Comput. Phys., 188 (2), 573-592 (2003) L. Chac'on, 32nd EPS Conf. Plasma Physics, Tarragona, Spain, 2005 L. Chac'on et al., 33rd EPS Conf. Plasma Physics, Rome, Italy, 2006
Electrodeless Plasma Source: Phase II Update
NASA Astrophysics Data System (ADS)
Prager, James; Ziemba, Timothy; Miller, Kenneth
2012-10-01
Eagle Harbor Technologies, in collaboration with the University of Washington, has developed a low-impurity, electrode-less plasma source (EPS) for start-up and source plasma injection for fusion science applications. In order to not interfere with the experiment, a pre-ionizer/plasma source must meet a few critical criteria including low impurity production, low electromagnetic interference (EMI), and minimal disruption to the magnetic geometry of the experiment. This system was designed to be UHV compatible and bakable. Here we present the results of the EPS Phase II upgrade. The output plasma density was increased by two orders of magnitude to >10^17 m-3 in hydrogen with no magnetic field injected. EPS system integration with the HIT-SI experiment has begun.
Exercise- and cold-induced changes in plasma beta-endorphin and beta-lipotropin in men and women.
Viswanathan, M; Van Dijk, J P; Graham, T E; Bonen, A; George, J C
1987-02-01
The plasma beta-endorphin (beta-EP) and beta-lipotropin (beta-LPH) response of men, eumenorrheic women, and amenorrheic women (n = 6) to 1 h of rest or to a bicycle ergometer test [20 min at 30% maximum O2 uptake (VO2max), 20 min at 60% VO2max, and at 90% VO2max to exhaustion] was studied in both normal (22 degrees C) and cold (5 degrees C) environments. beta-EP and beta-LPH was measured by radioimmunoassay in venous samples collected every 20 min during rest or after each exercise bout. Exhaustive exercise at ambient temperature (Ta) 22 degrees C induced significant increases in plasma beta-EP and beta-LPH in all subjects as did work at 60% VO2max in amenorrheic and eumenorrheic women. During work at Ta 5 degrees C, the relative increase in beta-EP and beta-LPH was suppressed in eumenorrheic women and completely prevented in amenorrheic women. Although significant lowering of beta-EP and beta-LPH was observed in men and eumenorrheic women during rest at 5 degrees C, amenorrheic women maintained precold exposure levels. These findings suggest that plasma beta-EP and beta-LPH may reflect a thermoregulatory response to heat load. There appears to be a sexual dimorphism in exercise- and cold-induced release of beta-EP and beta-LPH and amenorrhea may be accompanied by alterations in these responses.
Liu, Bin; Sun, Zheng; Ma, Xiaonian; Yang, Bo; Jiang, Yue; Wei, Dong; Chen, Feng
2015-01-01
Extracellular polysaccharides (EPS) produced by marine microalgae have the potential to be used as antioxidants, antiviral agents, immunomodulators, and anti-inflammatory agents. Although the marine microalga Crypthecodinium cohnii releases EPS during the process of docosahexaenoic acid (DHA) production, the yield of EPS remains relatively low. To improve the EPS production, a novel mutagenesis of C. cohnii was conducted by atmospheric and room temperature plasma (ARTP). Of the 12 mutants obtained, 10 mutants exhibited significantly enhanced EPS yield on biomass as compared with the wild type strain. Among them, mutant M7 was the best as it could produce an EPS volumetric yield of 1.02 g/L, EPS yield on biomass of 0.39 g/g and EPS yield on glucose of 94 mg/g, which were 33.85%, 85.35% and 57.17% higher than that of the wild type strain, respectively. Results of the present study indicated that mutagenesis of the marine microalga C. cohnii by ARTP was highly effective leading to the high-yield production of EPS. PMID:25872142
Kinetic electromagnetic instabilities in an ITB plasma with weak magnetic shear
NASA Astrophysics Data System (ADS)
Chen, W.; Yu, D. L.; Ma, R. R.; Shi, P. W.; Li, Y. Y.; Shi, Z. B.; Du, H. R.; Ji, X. Q.; Jiang, M.; Yu, L. M.; Yuan, B. S.; Li, Y. G.; Yang, Z. C.; Zhong, W. L.; Qiu, Z. Y.; Ding, X. T.; Dong, J. Q.; Wang, Z. X.; Wei, H. L.; Cao, J. Y.; Song, S. D.; Song, X. M.; Liu, Yi.; Yang, Q. W.; Xu, M.; Duan, X. R.
2018-05-01
Kinetic Alfvén and pressure gradient driven instabilities are very common in magnetized plasmas, both in space and the laboratory. These instabilities will be easily excited by energetic particles (EPs) and/or pressure gradients in present-day fusion and future burning plasmas. This will not only cause the loss and redistribution of the EPs, but also affect plasma confinement and transport. Alfvénic ion temperature gradient (AITG) instabilities with the frequency ω_BAE<ω<ω_TAE and the toroidal mode numbers n=2{-}8 are found to be unstable in NBI internal transport barrier plasmas with weak shear and low pressure gradients, where ω_BAE and ω_TAE are the frequencies of the beta- and toroidicity-induced Alfvén eigenmodes, respectively. The measured results are consistent with the general fishbone-like dispersion relation and kinetic ballooning mode equation, and the modes become more unstable the smaller the magnetic shear is in low pressure gradient regions. The interaction between AITG activity and EPs also needs to be investigated with greater attention in fusion plasmas, such as ITER (Tomabechi and The ITER Team 1991 Nucl. Fusion 31 1135), since these fluctuations can be enhanced by weak magnetic shear and EPs.
Phase space effects on fast ion distribution function modeling in tokamaks
Podesta, M.; Gorelenkova, M.; Fredrickson, E. D.; ...
2016-04-14
Here, integrated simulations of tokamak discharges typically rely on classical physics to model energetic particle (EP) dynamics. However, there are numerous cases in which energetic particles can suffer additional transport that is not classical in nature. Examples include transport by applied 3D magnetic perturbations and, more notably, by plasma instabilities. Focusing on the effects of instabilities,ad-hocmodels can empirically reproduce increased transport, but the choice of transport coefficients is usually somehow arbitrary. New approaches based on physics-based reduced models are being developed to address those issues in a simplified way, while retaining a more correct treatment of resonant wave-particle interactions. Themore » kick model implemented in the tokamaktransport code TRANSP is an example of such reduced models. It includes modifications of the EP distribution by instabilities in real and velocity space, retaining correlations between transport in energy and space typical of resonant EP transport. The relevance of EP phase space modifications by instabilities is first discussed in terms of predicted fast ion distribution. Results are compared with those from a simple, ad-hoc diffusive model. It is then shown that the phase-space resolved model can also provide additional insight into important issues such as internal consistency of the simulations and mode stability through the analysis of the power exchanged between energetic particles and the instabilities.« less
Inhibition of endogenous pyrogen-induced fever by a muramyl dipeptide derivative.
Parant, M; Riveau, G; Parant, F; Chedid, L
1984-09-01
N-acetylmuramyl-L-alanyl-D-isoglutamine, or muramyl dipeptide (MDP), is a synthetic immunoadjuvant analogue of a bacterial peptidoglycan subunit that has a definite pyrogenic effect in the rabbit. Some adjuvant-active derivatives such as murabutide [MDP(Gln)-OnBu] or murametide [MDP(Gln)-OMe] are not pyrogenic. Murabutide did not stimulate human or rabbit cells to release endogenous pyrogen (EP), but murametide induced EP production at the same dosage levels as MDP. Moreover, plasma from rabbits treated with murametide transferred into untreated recipients elicited a febrile response typical of EP fever and comparable with that induced by plasma from MDP-treated animals. Murametide not only inhibited the central effect of EP that is generated but also the effect of an extra dose of EP administered later by the intravenous route. Moreover, pretreatment of rabbits with murametide decreased fever responses induced by certain high-molecular-weight exogenous pyrogens as mediated through the production of EP.
Suzuki, Hidenobu; Gen, Keishi
2012-03-01
Blonanserin is a second-generation antipsychotic that was developed in Japan. We investigated the relationships between plasma concentration, the plasma anti-5-HT(2A) activity/anti-D₂ activity (S/D) ratio and extrapyramidal symptoms (EPS) in blonanserin dosing. The subjects were 29 outpatients with schizophrenia. We assessed EPS using the Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS). The plasma concentrations were measured by high performance liquid chromatography, and the plasma anti-D₂ and anti-5-HT(2A) activities were measured by [³H]-spiperone and [³H]-ketanserin radioreceptor assays. The results revealed that there were significant correlations between both the plasma concentration and the DIEPSS total score (P<0.05). A negative correlative tendency was found between the S/D ratio and the DIEPSS total score. Furthermore, the plasma concentrations were divided into a low plasma concentration group and a high plasma concentration group, and the S/D ratios were divided into a low S/D ratio group and a high S/D ratio group. We then compared each group based on the DIEPSS total scores. The score in the high plasma concentration-low S/D ratio group was significantly higher than in the high plasma concentration-high S/D ratio, low plasma concentration-high S/D ratio and low plasma concentration-low S/D ratio groups (P<0.05 for all). These findings indicate that the incidence of EPS during treatment with blonanserin is mainly determined by plasma concentration, but the incidence of EPS may be inhibited when anti-5HT(2A) activity is predominant over anti-D₂ activity. © 2012 The Authors. Psychiatry and Clinical Neurosciences © 2012 Japanese Society of Psychiatry and Neurology.
Radioimmunoassay of erythropoietin: circulating levels in normal and polycythemic human beings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garcia, J.F.; Ebbe, S.N.; Hollander, L.
1982-05-01
Techniques are described in detail for the RIA of human Ep in unextracted plasma or serum. With 100 ..mu..l of sample, the assay is sensitive at an Ep concentration of approximately 4 mU/ml, and when required, the sensitivity can be increased to 0.4 mU/ml, a range considerably less than the concentration observed in normal human beings. This is approximately 100 times more sensitive than existing in vivo bioassays for this hormone. Studies concerned with the validation of the Ep RIA show a high degree of correlation with the polycythemic mouse bioassay. Dilutions of a variety of human serum samples showmore » a parallel relationship with the standard reference preparation for Ep. Validation of the RIA is further confirmed by observations of appropriate increases or decreases of circulating Ep levels in physiological and clinical conditions known to be associated with stimulation or suppression of Ep secretion. Significantly different mean serum concentrations of 17.2 mU/ml for normal male subjects and 18.8 mU/ml for normal female subjects were observed. Mean plasma Ep concentrations in patients with polycythemia vera are significantly decreased, and those of patients with secondary polycythemia are significantly increased as compared to plasma levels in normal subjects. These results demonstrate an initial practical value of the Ep RA in the hematology clinic, which will most certainly be expanded with its more extensive use.« less
NASA Astrophysics Data System (ADS)
Matsunaga, G.; Okabayashi, M.; Aiba, N.; Boedo, J. A.; Ferron, J. R.; Hanson, J. M.; Hao, G. Z.; Heidbrink, W. W.; Holcomb, C. T.; In, Y.; Jackson, G. L.; Liu, Y. Q.; Luce, T. C.; McKee, G. R.; Osborne, T. H.; Pace, D. C.; Shinohara, K.; Snyder, P. B.; Solomon, W. M.; Strait, E. J.; Turnbull, A. D.; Van Zeeland, M. A.; Watkins, J. G.; Zeng, L.; the DIII-D Team; the JT-60 Team
2013-12-01
In the wall-stabilized high-β plasmas in JT-60U and DIII-D, interactions between energetic particle (EP) driven modes (EPdMs) and edge localized modes (ELMs) have been observed. The interaction between the EPdM and ELM are reproducibly observed. Many EP diagnostics indicate a strong correlation between the distorted waveform of the EPdM and the EP transport to the edge. The waveform distortion is composed of higher harmonics (n ⩾ 2) and looks like a density snake near the plasma edge. According to statistical analyses, ELM triggering by the EPdMs requires a finite level of waveform distortion and pedestal recovery. ELM pacing by the EPdMs occurs when the repetition frequency of the EPdMs is higher than the natural ELM frequency. EPs transported by EPdMs are thought to contribute to change the edge stability.
Influence of insulin on beta-endorphin plasma levels in obese and normal weight subjects.
Brunani, A; Pincelli, A I; Pasqualinotto, L; Tibaldi, A; Baldi, G; Scacchi, M; Fatti, L M; Cavagnini, F
1996-08-01
To establish the possible role of hyperinsulinemia in the elevation of plasma beta-endorphin (beta-EP) levels observed in obese patients after an oral glucose load. Oral glucose tolerance test (OGTT) and euglycemic-hyperinsulinemic clamp. Two groups of six (age: 22-39 y, BMI: 30-48 kg/m2) and eight obese men (age: 18-37 y, BMI: 35-45 kg/m2), respectively, and five normal weight healthy men (age: 22-30 y, BMI 22-23 kg/m2). Glucose, insulin and beta-EP levels at baseline and every 30 min until 180 min during the OGTT; glucose, insulin, C-peptide and beta-EP concentrations at baseline and in steady state condition (i.e. during the last 30 min of insulin infusion) in the euglycemic-hyperinsulinemic clamp studies. In the six obese patients undergoing the OGTT a significant elevation of beta-EP plasma levels was observed between 60 and 90 min after glucose ingestion. In the clamp studies no significant differences in beta-EP plasma levels, blood glucose and serum insulin were observed between obese and normal weight subjects both at baseline and at steady state. A markedly diminished insulin sensitivity along with a lower inhibition of C-peptide during insulin infusion was observed in obese patients compared to control subjects. A rise in serum insulin levels unaccompanied by a concomitant increase in blood glucose concentration is unable to elicit a beta-EP response in obese patients.
of plasma membranes of eukaryotic cells in vitro and in vivo. The physical to biological driving mechanisms behind nanoporation still remain unclear...but could be a result of a multitude of stimuli, including mechanical (shockwaves, electrode formation), thermal, and electrical (ion transport...channel gating). Experimentally quantifying and characterizing mechanical fields with piezoelectric transducers proves difficult due to electromagnetic
NASA Astrophysics Data System (ADS)
Vardanyan, E. L.; Budilov, V. V.; Ramazanov, K. N.; Khusnimardanov, R. N.; Nagimov, R. Sh
2017-05-01
The operation conditions and mechanism of wear of slotting tools from high-speed steel was researched. The analysis of methods increasing durability was carried out. The effect of intermetallic coatings deposited from vacuum-arc discharge plasma on the physical-mechanical high-speed steel EP657MP was discovered. The pilot batch of the slotting tool and production tests were carried out.
NASA Astrophysics Data System (ADS)
Huismann, Tyler D.
Due to the rapidly expanding role of electric propulsion (EP) devices, it is important to evaluate their integration with other spacecraft systems. Specifically, EP device plumes can play a major role in spacecraft integration, and as such, accurate characterization of plume structure bears on mission success. This dissertation addresses issues related to accurate prediction of plume structure in a particular type of EP device, a Hall thruster. This is done in two ways: first, by coupling current plume simulation models with current models that simulate a Hall thruster's internal plasma behavior; second, by improving plume simulation models and thereby increasing physical fidelity. These methods are assessed by comparing simulated results to experimental measurements. Assessment indicates the two methods improve plume modeling capabilities significantly: using far-field ion current density as a metric, these approaches used in conjunction improve agreement with measurements by a factor of 2.5, as compared to previous methods. Based on comparison to experimental measurements, recent computational work on discharge chamber modeling has been largely successful in predicting properties of internal thruster plasmas. This model can provide detailed information on plasma properties at a variety of locations. Frequently, experimental data is not available at many locations that are of interest regarding computational models. Excepting the presence of experimental data, there are limited alternatives for scientifically determining plasma properties that are necessary as inputs into plume simulations. Therefore, this dissertation focuses on coupling current models that simulate internal thruster plasma behavior with plume simulation models. Further, recent experimental work on atom-ion interactions has provided a better understanding of particle collisions within plasmas. This experimental work is used to update collision models in a current plume simulation code. Previous versions of the code assume an unknown dependence between particles' pre-collision velocities and post-collision scattering angles. This dissertation focuses on updating several of these types of collisions by assuming a curve fit based on the measurements of atom-ion interactions, such that previously unknown angular dependences are well-characterized.
DOE Office of Scientific and Technical Information (OSTI.GOV)
John D. Bess; J. Blair Briggs; Jim Gulliford
2014-10-01
The International Reactor Physics Experiment Evaluation Project (IRPhEP) is a widely recognized world class program. The work of the IRPhEP is documented in the International Handbook of Evaluated Reactor Physics Benchmark Experiments (IRPhEP Handbook). Integral data from the IRPhEP Handbook is used by reactor safety and design, nuclear data, criticality safety, and analytical methods development specialists, worldwide, to perform necessary validations of their calculational techniques. The IRPhEP Handbook is among the most frequently quoted reference in the nuclear industry and is expected to be a valuable resource for future decades.
Plasma equilibrium with fast ion orbit width, pressure anisotropy, and toroidal flow effects
Gorelenkov, Nikolai N.; Zakharov, Leonid E.
2018-04-27
Here, we formulate the problem of tokamak plasma equilibrium including the toroidal flow and fast ion (or energetic particle, EP) pressure anisotropy and the finite drift orbit width (FOW) effects. The problem is formulated via the standard Grad-Shafranov equation (GShE) amended by the solvability condition which imposes physical constraints on allowed spacial dependencies of the anisotropic pressure. The GShE problem employs the pressure coupling scheme and includes the dominant diagonal terms and non-diagonal corrections to the standard pressure tensor. The anisotropic tensor elements are obtained via the distribution function represented in the factorized form via the constants of motion. Consideredmore » effects on the plasma equilibrium are estimated analytically, if possible, to understand their importance for GShE tokamak plasma problem.« less
Plasma equilibrium with fast ion orbit width, pressure anisotropy, and toroidal flow effects
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gorelenkov, Nikolai N.; Zakharov, Leonid E.
Here, we formulate the problem of tokamak plasma equilibrium including the toroidal flow and fast ion (or energetic particle, EP) pressure anisotropy and the finite drift orbit width (FOW) effects. The problem is formulated via the standard Grad-Shafranov equation (GShE) amended by the solvability condition which imposes physical constraints on allowed spacial dependencies of the anisotropic pressure. The GShE problem employs the pressure coupling scheme and includes the dominant diagonal terms and non-diagonal corrections to the standard pressure tensor. The anisotropic tensor elements are obtained via the distribution function represented in the factorized form via the constants of motion. Consideredmore » effects on the plasma equilibrium are estimated analytically, if possible, to understand their importance for GShE tokamak plasma problem.« less
The Spherical Tokamak MEDUSA for Costa Rica
NASA Astrophysics Data System (ADS)
Ribeiro, Celso; Vargas, Ivan; Guadamuz, Saul; Mora, Jaime; Ansejo, Jose; Zamora, Esteban; Herrera, Julio; Chaves, Esteban; Romero, Carlos
2012-10-01
The former spherical tokamak (ST) MEDUSA (Madison EDUcation Small Aspect.ratio tokamak, R<0.14m, a<0.10m, BT<0.5T, Ip<40kA, 3ms pulse)[1] is in a process of donation to Costa Rica Institute of Technology. The main objective of MEDUSA is to train students in plasma physics /technical related issues which will help all tasks of the very low aspect ratio stellarator SCR-1(A≡R/>=3.6, under design[2]) and also the ongoing activities in low temperature plasmas. Courses in plasma physics at undergraduate and post-graduate joint programme levels are regularly conducted. The scientific programme is intend to clarify several issues in relevant physics for conventional and mainly STs, including transport, heating and current drive via Alfv'en wave, and natural divertor STs with ergodic magnetic limiter[3,4]. [1] G.D.Garstka, PhD thesis, University of Wisconsin at Madison, 1997 [2] L.Barillas et al., Proc. 19^th Int. Conf. Nucl. Eng., Japan, 2011 [3] C.Ribeiro et al., IEEJ Trans. Electrical and Electronic Eng., 2012(accepted) [4] C.Ribeiro et al., Proc. 39^th EPS Conf. Contr. Fusion and Plasma Phys., Sweden, 2012
NASA Astrophysics Data System (ADS)
Sarff, J. S.
2016-10-01
MST progress in advancing the RFP for (1) fusion plasma confinement with ohmic heating and minimal external magnetization, (2) predictive capability in toroidal confinement physics, and (3) basic plasma physics is summarized. Validation of key plasma models is a program priority. Programmable power supplies (PPS) are being developed to maximize inductive capability. Well-controlled flattops with current as low as 0.02 MA are produced with an existing PPS, and Ip <= 0.8 MA is anticipated with a second PPS under construction. The Lundquist number spans S =10(4 - 9) for 0.02-0.8 MA, allowing nonlinear MHD validation using NIMROD and DEBS at low S to be connected to highest S experiments. The PPS also enables MST tokamak operation for studying transients and runaway electron suppression with RMPs. Gyrokinetic modeling with GENE predicts unstable TEM in improved-confinement plasmas. Fluctuations are measured with TEM properties including a density-gradient threshold larger than for tokamak plasmas. Probe measurements hint that drift waves are also excited via the turbulent cascade in standard RFP plasmas. Turbulent energization of an electron tail occurs during sawtooth reconnection. New diagnostics are being developed to measure the energetic ion profile and transport from EP instabilities with NBI. Supported by US DoE and NSF.
Mahmoodpoor, Ata; Hamishehkar, Hadi; Fattahi, Vahid; Sanaie, Sarvin; Arora, Pradeep; Nader, Nader D
2018-02-01
To examine urinary and plasma neutrophil gelatinase-associated lipocalin (NGAL) levels in predicting ICU mortality. Prospective observational. University Critical Care setting. 50 patients with acute kidney injury (AKI). None. Serial urinary and plasma concentrations of NGAL were measured. Twenty-five patients had early progression (EP) and 25 patients had early improvement (EI) of AKI. Plasma concentrations of NGAL in the EP group (N=25) were significantly higher than those in the EI group (129 [IQR; 20] vs. 111 [IQR; 32] ng/mL; P=0.009), while urine NGAL levels on admission were similar in both groups (61 [IQR; 20] vs. 65 [IQR; 20] ng/mL; P=0.767). Plasma NGAL concentrations rapidly decreased to 87 [32] ng/mL in the EI group (P<0.001) and while it remained elevated in the EP group (138 [21] ng/mL). Within 28-days, 50% of the patients died in the EP group, whereas no patient died in the EI group (P<0.001). Plasma NGAL was a fair predictor for progression of AKI (AUC; 0.719±0.063; P=0.006). 48-hour changes in plasma NGAL levels predicted death within 28-days of ICU admission (AUC; 0.874±0.048; P<0.001). Early progression of AKI was associated with more death within 28 and 90days. While one time measurement of plasma NGAL levels at the time ICU admission may represent the kidney health status in critical care settings, it does not reliably predict mortality. On the other hand, changes in plasma NGAL within 48h of admission improve the value of this biomarker in predicting ICU mortality. Published by Elsevier Inc.
Pharmacokinetics of erythropoietin in intact and anephric dogs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fu, J.S.; Lertora, J.J.; Brookins, J.
1988-06-01
The present studies were performed to determine the pharmacokinetic parameters of erythropoietin in intact and anephric dogs by use of unlabeled crude native erythropoietin (nEp) and iodine 125-labeled purified recombinant erythropoietin (rEp) given by intravenous infusion for 15 minutes. Sephadex G-75 gel filtration was used to confirm that the 125I-rEp molecule remained iodinated in dog plasma during the 24-hour period of these studies. The plasma disappearance of erythropoietin conformed to a biexponential equation for both nEp and 125I-rEp, with the central compartment being larger than the peripheral compartment. The mean distribution half-life of 75.3 +/- 21.2 minutes for nEp wasmore » significantly (p less than 0.05) longer than that of 125I-rEp (23.7 +/- 5.0 minutes) in intact dogs. The intercompartmental clearance (CIic) for nEp (0.018 +/- 0.006 L/kg/hr) was significantly smaller than that of 125I-rEp (0.068 +/- 0.018 L/kg/hr) in intact dogs (p less than 0.05). There were no significant differences in apparent volume of distribution, elimination half-life, and elimination clearance (CIe) for nEp and rEp in intact dogs. The mean elimination half-life for 125I-rEp in intact dogs (9.0 +/- 0.6 hours) and anephric dogs (13.8 +/- 1.4 hours) was significantly different (p less than 0.05). The CIe for 125I-rEp in anephric dogs (0.008 +/- 0.001 L/kg/hr) was significantly (p less than 0.05) smaller than that of 125I-rEp in intact dogs (0.011 +/- 0.001 L/kg/hr). There were no significant differences in apparent volume of distribution, distribution half-life, and CIic for 125I-rEp in intact and anephric dogs.« less
O'Rand, Michael G; Hamil, Katherine G; Adevai, Tiffany; Zelinski, Mary
2018-01-01
Men have two practical choices for contraception; the condom which has a high typical use failure rate or vasectomy. New male hormonal and non-hormonal contraceptives are under development that target either the production of sperm (spermatogenesis) or the delivery of sperm. One particular target is the sperm protein EPPIN, which is present on the surface of human spermatozoa. EP055 is a small organic compound that targets EPPIN on the surface of sperm and inhibits motility. EP055 was tested in cynomolgus (Macaca fascicularis) males to determine its plasma half-life after intravenous (i.v.) infusion of a single dose and for binding to its target tissues. Our initial study demonstrated a plasma half-life for EP055 of 10.6 minutes. In a second study examination of macaque testis, epididymis, and plasma after i.v. infusion of a single dose of compound EP055 (63.25 mg/kg) demonstrated that EP055 was detected in testis and epididymis two hours and six hours post-infusion. We initiated a trial in rhesus (Macaca mulatta) males to assess the availability of EP055 in semen and its effect on sperm motility as a measure of the drug's efficacy. Four macaques were infused with a low dose (75-80 mg/kg) followed by a recovery period and a subsequent high dose (125-130 mg/kg) of EP055. After high dose administration, sperm motility fell to approximately 20% of pretreatment levels within 6 hours post-infusion; no normal motility was observed at 30 hours post-infusion. Recovery of sperm motility was obvious by 78 hours post-infusion; with full recovery in all animals by 18 days post-infusion. EP055 has the potential to be a male contraceptive that would provide a reversible, short-lived pharmacological alternative.
Baxi, Sanjiv M; Liu, Albert; Bacchetti, Peter; Mutua, Gaudensia; Sanders, Eduard J; Kibengo, Freddie M; Haberer, Jessica E; Rooney, James; Hendrix, Craig W; Anderson, Peter L; Huang, Yong; Priddy, Frances; Gandhi, Monica
2015-01-01
The efficacy of pre-exposure prophylaxis (PrEP) in HIV will diminish with poor adherence; pharmacologic measures of drug exposure have proven critical to PrEP trial interpretation. We assessed drug exposure in hair against other pharmacologic and more routinely used measures to assess pill-taking. Participants were randomized to placebo, daily PrEP, or intermittent PrEP to evaluate safety and tolerability of daily versus intermittent tenofovir/emtricitabine (TFV/FTC) in 2 phase II PrEP clinical trials conducted in Africa. Different measures of drug exposure, including self-report, medication event monitoring system (MEMS)-caps openings, and TFV/FTC levels in hair and other biomatrices were compared. At weeks 8 and 16, self-reported pill-taking, MEMS-caps openings, and TFV/FTC levels in hair, plasma, and peripheral blood mononuclear cells (PBMCs) were measured. Regression models evaluated predictors of TFV/FTC concentrations in the 3 biomatrices; correlation coefficients between pharmacologic and nonpharmacologic measures were calculated. Both trials were registered on ClinicalTrials.gov (NCT00931346/NCT00971230). Hair collection was highly feasible and acceptable (100% in week 8; 96% in week 16). In multivariate analysis, strong associations were seen between pharmacologic measures and MEMS-caps openings (all P < 0.001); self-report was only weakly associated with pharmacologic measures. TFV/FTC hair concentrations were significantly correlated with levels in plasma and PBMCs (correlation coefficients, 0.41-0.86, all P < 0.001). Measuring TFV/FTC exposure in small hair samples in African PrEP trials was feasible and acceptable. Hair levels correlated strongly with PBMC, plasma concentrations, and MEMS-caps openings. As in other PrEP trials, self-report was the weakest measure of exposure. Further study of hair TFV/FTC levels in PrEP trials and demonstration projects to assess adherence/exposure is warranted.
Baxi, Sanjiv M.; Liu, Albert; Bacchetti, Peter; Mutua, Gaudensia; Sanders, Eduard J.; Kibengo, Freddie M.; Haberer, Jessica E.; Rooney, James; Hendrix, Craig W.; Anderson, Peter L.; Huang, Yong; Priddy, Frances
2015-01-01
Objective: The efficacy of pre-exposure prophylaxis (PrEP) in HIV will diminish with poor adherence; pharmacologic measures of drug exposure have proven critical to PrEP trial interpretation. We assessed drug exposure in hair against other pharmacologic and more routinely used measures to assess pill-taking. Design: Participants were randomized to placebo, daily PrEP, or intermittent PrEP to evaluate safety and tolerability of daily versus intermittent tenofovir/emtricitabine (TFV/FTC) in 2 phase II PrEP clinical trials conducted in Africa. Different measures of drug exposure, including self-report, medication event monitoring system (MEMS)-caps openings, and TFV/FTC levels in hair and other biomatrices were compared. Methods: At weeks 8 and 16, self-reported pill-taking, MEMS-caps openings, and TFV/FTC levels in hair, plasma, and peripheral blood mononuclear cells (PBMCs) were measured. Regression models evaluated predictors of TFV/FTC concentrations in the 3 biomatrices; correlation coefficients between pharmacologic and nonpharmacologic measures were calculated. Both trials were registered on ClinicalTrials.gov (NCT00931346/NCT00971230). Results: Hair collection was highly feasible and acceptable (100% in week 8; 96% in week 16). In multivariate analysis, strong associations were seen between pharmacologic measures and MEMS-caps openings (all P < 0.001); self-report was only weakly associated with pharmacologic measures. TFV/FTC hair concentrations were significantly correlated with levels in plasma and PBMCs (correlation coefficients, 0.41–0.86, all P < 0.001). Conclusions: Measuring TFV/FTC exposure in small hair samples in African PrEP trials was feasible and acceptable. Hair levels correlated strongly with PBMC, plasma concentrations, and MEMS-caps openings. As in other PrEP trials, self-report was the weakest measure of exposure. Further study of hair TFV/FTC levels in PrEP trials and demonstration projects to assess adherence/exposure is warranted. PMID:25296098
The modern trends in space electromagnetic instrumentation
NASA Astrophysics Data System (ADS)
Korepanov, V.
The future trends of the experimental plasma physical development in outer space demands more and more exact and sophisticated scientific instrumentation. Moreover, the situation is complicated by constant reducing of financial support of scientific research, even in leading countries. This resulted in the development of mini, micro and nanosatellites with low price and short preparation time. Consequently, it provoked the creation of new generation of scientific instruments with reduced weight and power consumption but increased level of metrological parameters. The recent state of the development of electromagnetic (EM) sensors for microsatellites is reported. The set of EM sensors produced at LCISR includes following devices. Flux-gate magnetometers (FGM). The reduction of new of satellite versions FGM weight as well as power consumption was achieved not only due to the use of new electronic components but also because the development of new operation modes. To this the scientific and technological study allowed to decrease FGM noise and now typical figure is about 10 picotesla rms at 1 Hz and the record one is below 1 picotesla. Also because of satellite weight reduction the possibility was studied to use FGM only for satellite attitude control. The magnetic orientation and stabilization system was developed and new FGM for orientation was created. It uses industrial components and special measures are taken to increase its reliability. Search-coil magnetometers (SCM). The super-light version of SCM was created as the result of intensive scientific and technological research. These new SCMs can have about six decades operational frequency band noise with upper limit ~ 1 MHz and noise level of few femtotesla with total weight about 75 grams. Electric probes (EP). The study of operation condition of EP immersed in space plasma allowed to find the possibilities to decrease the EP weight conserving the same noise factor. Two types of EP operating from DC and from 0,1 Hz are created and successfully tested. Wave probe (WP). The WP is another kind of instrument which combines in one sensor three independent sensors: SCM, EP and split Langmuir probe. Such a combination allowed to create a principally new instru ment U wave probe. The developed theory confirms that WP can directly measure vector components in space plasma. All these space sensors are described and their experimentally obtained parameters are presented. This work was partially supported by INTAS grant 2000-465.
Lehman, Dara A.; Baeten, Jared M.; McCoy, Connor O.; Weis, Julie F.; Peterson, Dylan; Mbara, Gerald; Donnell, Deborah; Thomas, Katherine K.; Hendrix, Craig W.; Marzinke, Mark A.; Frenkel, Lisa; Ndase, Patrick; Mugo, Nelly R.; Celum, Connie; Overbaugh, Julie; Matsen, Frederick A.; Celum, Connie; Baeten, Jared M.; Donnell, Deborah; Coombs, Robert W.; Frenkel, Lisa; Hendrix, Craig W.; Marzinke, Mark A.; Lingappa, Jairam; McElrath, M. Juliana; Fife, Kenneth; Were, Edwin; Tumwesigye, Elioda; Ndase, Patrick; Katabira, Elly; Katabira, Elly; Ronald, Allan; Bukusi, Elizabeth; Cohen, Craig; Wangisi, Jonathan; Campbell, James; Tappero, Jordan; Kiarie, James; Farquhar, Carey; John-Stewart, Grace; Mugo, Nelly Rwamba; Campbell, James; Tappero, Jordan; Wangisi, Jonathan
2015-01-01
Background. Preexposure prophylaxis (PrEP) with emtricitabine plus tenofovir disoproxil fumarate (FTC/TDF) or TDF alone reduces the risk of human immunodeficiency virus (HIV) acquisition. Understanding the risk of antiretroviral resistance selected by PrEP during breakthrough infections is important because of the risk of treatment failure during subsequent antiretroviral use. Methods. Within the largest randomized trial of FTC/TDF versus TDF as PrEP, plasma samples were tested for HIV with resistance mutations associated with FTC (K65R and M184IV) and TDF (K65R and K70E), using 454 sequencing. Results. Of 121 HIV seroconverters, 25 received FTC/TDF, 38 received TDF, and 58 received placebo. Plasma drug levels in 26 individuals indicated PrEP use during or after HIV acquisition, of which 5 had virus with resistance mutations associated with their PrEP regimen. Among those with PrEP drug detected during infection, resistance was more frequent in the FTC/TDF arm (4 of 7 [57%]), compared with the TDF arm (1 of 19 [5.3%]; P = .01), owing to the FTC-associated mutation M184IV. Of these cases, 3 had unrecognized acute infection at PrEP randomization, and 2 were HIV negative at enrollment. Conclusions. These results suggest that resistance selected by PrEP is rare but can occur both with PrEP initiation during acute seronegative HIV infection and in PrEP breakthrough infections and that FTC is associated with a greater frequency of resistance mutations than TDF. PMID:25587020
Characterization of Pressure Transients Generated by Nanosecond Electrical Pulse (nsEP) Exposure.
Roth, Caleb C; Barnes, Ronald A; Ibey, Bennett L; Beier, Hope T; Christopher Mimun, L; Maswadi, Saher M; Shadaram, Mehdi; Glickman, Randolph D
2015-10-09
The mechanism(s) responsible for the breakdown (nanoporation) of cell plasma membranes after nanosecond pulse (nsEP) exposure remains poorly understood. Current theories focus exclusively on the electrical field, citing electrostriction, water dipole alignment and/or electrodeformation as the primary mechanisms for pore formation. However, the delivery of a high-voltage nsEP to cells by tungsten electrodes creates a multitude of biophysical phenomena, including electrohydraulic cavitation, electrochemical interactions, thermoelastic expansion, and others. To date, very limited research has investigated non-electric phenomena occurring during nsEP exposures and their potential effect on cell nanoporation. Of primary interest is the production of acoustic shock waves during nsEP exposure, as it is known that acoustic shock waves can cause membrane poration (sonoporation). Based on these observations, our group characterized the acoustic pressure transients generated by nsEP and determined if such transients played any role in nanoporation. In this paper, we show that nsEP exposures, equivalent to those used in cellular studies, are capable of generating high-frequency (2.5 MHz), high-intensity (>13 kPa) pressure transients. Using confocal microscopy to measure cell uptake of YO-PRO®-1 (indicator of nanoporation of the plasma membrane) and changing the electrode geometry, we determined that acoustic waves alone are not responsible for poration of the membrane.
2015-04-01
in the Environments of Space and Testing (EP TEMPEST ) - Program Review (Briefing Charts) 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c...of Space and Testing (EP TEMPEST ) AFOSR T&E Program Review 13-17 April 2015 Dr. Daniel L. Brown In-Space Propulsion Branch (RQRS) Aerospace Systems...Statement A: Approved for public release; distribution is unlimited. EP TEMPEST (Lab Task, FY14-FY16) Program Goals and Objectives Title: Electric
Li, Wusun; Yuan, Shuzhi; Sun, Jing; Li, Qianqian; Jiang, Weibo; Cao, Jiankang
2018-08-02
The fungus Alternaria alternata can cause food contamination by black spot rot and food safety issues due to the production of mycotoxins. In particular, A. alternata can infect many fresh fruits and vegetables and lead to considerable postharvest decay during storage and processing. The use of plant-derived products in postharvest disease management may be an acceptable alternative to traditional chemical fungicides. The aim of this study was to assess the antifungal activity of ethyl p-coumarate (EpCA) against Alternaria alternata in vitro and in vivo, and to determine the underlying mechanism. Results indicated that EpCA exhibited pronounced antifungal activity against in vitro mycelial growth of A. alternata, with half-inhibition concentration of 176.8 μg/mL. Spore germination of the pathogen was inhibited by EpCA in a dose-dependent manner. Moreover, in vivo test confirmed that both 100 and 800 μg/mL EpCA significantly reduced disease development of black spot rot in jujube fruit caused by A. alternata. The EpCA treatments increased plasma membrane permeability as great leakage of intercellular electrolytes, soluble proteins and sugars of A. alternata occurred during incubation. The EpCA treatments also caused increase of the influx of propidium iodide, a fluorescence dye binding nucleus DNA, into the affected spores, indicating the disrupted plasma membrane integrity. Observations of ultrastructure further evidenced the damage to plasma membrane and morphology of A. alternata caused by EpCA, which resulted in distortion, sunken and shrivelled of spores and mycelia of the pathogen. In addition, fluorometric assay by confocal laser scanning microscopy confirmed that the EpCA treatments induced endogenous reactive oxygen species (ROS) formation in the spores of A. alternata, with stronger and more stable accumulation of ROS at higher concentration of EpCA. Therefore, heavy oxidative damage to cellular membranes and organelles might happen as demonstrated by the severe occurrence of lipid peroxidation of the pathogen treated with EpCA. Taken together, these results indicated that EpCA exerts antifungal activity via membrane-targeted mechanism and it would be a promising candidate to control postharvest diseases of fruits. Copyright © 2018 Elsevier B.V. All rights reserved.
Heffron, Renee; Ngure, Kenneth; Odoyo, Josephine; Bulya, Nulu; Tindimwebwa, Edna; Hong, Ting; Kidoguchi, Lara; Donnell, Deborah; Mugo, Nelly R.; Bukusi, Elizabeth A.; Katabira, Elly; Asiimwe, Stephen; Morton, Jennifer; Morrison, Susan; Haugen, Harald; Mujugira, Andrew; Haberer, Jessica E.; Ware, Norma C.; Wyatt, Monique A.; Marzinke, Mark A.; Frenkel, Lisa M.; Celum, Connie; Baeten, Jared M.
2017-01-01
Introduction: Pre-exposure prophylaxis (PrEP) can provide high protection against HIV infection and is a recommended intervention for HIV-negative persons with substantial HIV risk, such as individuals with a partner living with HIV. Demonstration projects of PrEP have been conducted in diverse settings worldwide to illustrate practical examples of how PrEP can be delivered. Methods: We evaluated delivery of PrEP for HIV-negative partners within heterosexual HIV serodiscordant couples in an open-label demonstration project in East Africa. The delivery model integrated PrEP into HIV treatment services, prioritizing PrEP for HIV-negative partners within serodiscordant couples prior to and during the first 6 months after the partner living with HIV initiated antiretroviral therapy (ART). We measured adherence to PrEP through medication event monitoring system (MEMS) bottle caps and quantification of tenofovir in plasma among a random sample of participants. We estimated HIV infections prevented using a counterfactual cohort simulated from the placebo arm of a previous PrEP clinical trial. Results: We enrolled 1,010 HIV serodiscordant couples that were naïve to ART and PrEP. Ninety-seven percent (97%) of HIV-negative partners initiated PrEP, and when PrEP was dispensed, objective measures suggest high adherence: 71% of HIV-negative participants took ≥80% of expected doses, as recorded via MEMS, and 81% of plasma samples had tenofovir detected. A total of 4 incident HIV infections were observed (incidence rate=0.24 per 100 person-years), a 95% reduction (95% CI 86-98%, p<0.0001) in HIV incidence, relative to estimated HIV incidence for the population in the absence of PrEP integrated into HIV treatment services. Conclusions: PrEP uptake and adherence were high and incident HIV was rare in this PrEP demonstration project for African HIV-negative individuals whose partners were known to be living with HIV. Delivery of PrEP to HIV-negative partners within HIV serodiscordant couples was feasible and should be prioritized for wide-scale implementation. PMID:29355231
Heffron, Renee; Ngure, Kenneth; Odoyo, Josephine; Bulya, Nulu; Tindimwebwa, Edna; Hong, Ting; Kidoguchi, Lara; Donnell, Deborah; Mugo, Nelly R; Bukusi, Elizabeth A; Katabira, Elly; Asiimwe, Stephen; Morton, Jennifer; Morrison, Susan; Haugen, Harald; Mujugira, Andrew; Haberer, Jessica E; Ware, Norma C; Wyatt, Monique A; Marzinke, Mark A; Frenkel, Lisa M; Celum, Connie; Baeten, Jared M
2017-11-06
Introduction : Pre-exposure prophylaxis (PrEP) can provide high protection against HIV infection and is a recommended intervention for HIV-negative persons with substantial HIV risk, such as individuals with a partner living with HIV. Demonstration projects of PrEP have been conducted in diverse settings worldwide to illustrate practical examples of how PrEP can be delivered. Methods : We evaluated delivery of PrEP for HIV-negative partners within heterosexual HIV serodiscordant couples in an open-label demonstration project in East Africa. The delivery model integrated PrEP into HIV treatment services, prioritizing PrEP for HIV-negative partners within serodiscordant couples prior to and during the first 6 months after the partner living with HIV initiated antiretroviral therapy (ART). We measured adherence to PrEP through medication event monitoring system (MEMS) bottle caps and quantification of tenofovir in plasma among a random sample of participants. We estimated HIV infections prevented using a counterfactual cohort simulated from the placebo arm of a previous PrEP clinical trial. Results : We enrolled 1,010 HIV serodiscordant couples that were naïve to ART and PrEP. Ninety-seven percent (97%) of HIV-negative partners initiated PrEP, and when PrEP was dispensed, objective measures suggest high adherence: 71% of HIV-negative participants took ≥80% of expected doses, as recorded via MEMS, and 81% of plasma samples had tenofovir detected. A total of 4 incident HIV infections were observed (incidence rate=0.24 per 100 person-years), a 95% reduction (95% CI 86-98%, p<0.0001) in HIV incidence, relative to estimated HIV incidence for the population in the absence of PrEP integrated into HIV treatment services. Conclusions : PrEP uptake and adherence were high and incident HIV was rare in this PrEP demonstration project for African HIV-negative individuals whose partners were known to be living with HIV. Delivery of PrEP to HIV-negative partners within HIV serodiscordant couples was feasible and should be prioritized for wide-scale implementation.
Characterization of Pressure Transients Generated by Nanosecond Electrical Pulse (nsEP) Exposure
Roth, Caleb C.; Barnes Jr., Ronald A.; Ibey, Bennett L.; Beier, Hope T.; Christopher Mimun, L.; Maswadi, Saher M.; Shadaram, Mehdi; Glickman, Randolph D.
2015-01-01
The mechanism(s) responsible for the breakdown (nanoporation) of cell plasma membranes after nanosecond pulse (nsEP) exposure remains poorly understood. Current theories focus exclusively on the electrical field, citing electrostriction, water dipole alignment and/or electrodeformation as the primary mechanisms for pore formation. However, the delivery of a high-voltage nsEP to cells by tungsten electrodes creates a multitude of biophysical phenomena, including electrohydraulic cavitation, electrochemical interactions, thermoelastic expansion, and others. To date, very limited research has investigated non-electric phenomena occurring during nsEP exposures and their potential effect on cell nanoporation. Of primary interest is the production of acoustic shock waves during nsEP exposure, as it is known that acoustic shock waves can cause membrane poration (sonoporation). Based on these observations, our group characterized the acoustic pressure transients generated by nsEP and determined if such transients played any role in nanoporation. In this paper, we show that nsEP exposures, equivalent to those used in cellular studies, are capable of generating high-frequency (2.5 MHz), high-intensity (>13 kPa) pressure transients. Using confocal microscopy to measure cell uptake of YO-PRO®-1 (indicator of nanoporation of the plasma membrane) and changing the electrode geometry, we determined that acoustic waves alone are not responsible for poration of the membrane. PMID:26450165
Destabilization of counter-propagating TAEs by off-axis, co-current Neutral Beam Injection
NASA Astrophysics Data System (ADS)
Podesta', M.; Fredrickson, E.; Gorelenkova, M.
2017-10-01
Neutral Beam injection (NBI) is a common tool to heat the plasma and drive current non-inductively in fusion devices. Energetic particles (EP) resulting from NBI can drive instabilities that are detrimental for the performance and the predictability of plasma discharges. A broad NBI deposition profile, e.g. by off-axis injection aiming near the plasma mid-radius, is often assumed to limit those undesired effects by reducing the radial gradient of the EP density, thus reducing the ``universal'' drive for instabilities. However, this work presents new evidence that off-axis NBI can also lead to undesired effects such as the destabilization of Alfvénic instabilities, as observed in NSTX-U plasmas. Experimental observations indicate that counter propagating toroidal AEs are destabilized as the radial EP density profile becomes hollow as a result of off-axis NBI. Time-dependent analysis with the TRANSP code, augmented by a reduced fast ion transport model (known as kick model), indicates that instabilities are driven by a combination of radial and energy gradients in the EP distribution. Understanding the mechanisms for wave-particle interaction, revealed by the phase space resolved analysis, is the basis to identify strategies to mitigate or suppress the observed instabilities. Work supported by the U.S. Department of Energy, Office of Science, Office of Fusion Energy Sciences under Contract Number DE-AC02-09CH11466.
Extreme ultraviolet and Soft X-ray diagnostic upgrade on the HBT-EP tokamak: Progress and Results
NASA Astrophysics Data System (ADS)
Desanto, S.; Levesque, J. P.; Battey, A.; Brooks, J. W.; Mauel, M. E.; Navratil, G. A.; Hansen, C. J.
2017-10-01
In order to understand internal MHD mode structure in a tokamak plasma, it is helpful to understand temperature and density fluctuations within that plasma. In the HBT-EP tokamak, the plasma emits bremsstrahlung radiation in the extreme ultraviolet (EUV) and soft x-ray (SXR) regimes, and the emitted power is primarily related to electron density and temperature. This radiation is detected by photodiode arrays located at several different angular positions near the plasma's edge, each array making several views through a poloidal slice of plasma. From these measurements a 2-d emissivity profile of that slice can be reconstructed with tomographic algorithms. This profile cannot directly tell us whether the emissivity is due to electron density, temperature, line emission, or charge recombination; however, when combined with information from other diagnostics, it can provide strong evidence of the type of internal mode or modes depending on the temporal-spatial context. We present ongoing progress and results on the installation of a new system that will eventually consist of four arrays of 16 views each and a separate two-color, 16-chord tangential system, which will provide an improved understanding of the internal structure of HBT-EP plasmas. Supported by U.S. DOE Grant DE-FG02-86ER5322.
40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Test substance MP EP Test notes Product Chemistry and Composition 885.1100 Product identity R MP EP 885... and EP 2 885.1500 Certification of limits R MP EP Physical and Chemical Characteristics 830.6302 Color...
40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Test substance MP EP Test notes Product Chemistry and Composition 885.1100 Product identity R MP EP 885... and EP 2 885.1500 Certification of limits R MP EP Physical and Chemical Characteristics 830.6302 Color...
PREFACE: 26th Summer School and International Symposium on the Physics of Ionized Gases (SPIG 2012)
NASA Astrophysics Data System (ADS)
Kuraica, Milorad; Mijatovic, Zoran
2012-11-01
This volume of Journal of Physics: Conference Series contains the general invited lectures, topical invited lectures and progress reports presented at the 26th Summer School and International Symposium on the Physics of Ionized Gases - SPIG 2012. The conference was held in Zrenjanin, Serbia, from 27-31 August. The SPIG conference has a 52 year long tradition. The structure of the papers in this volume cover the following sections: atomic collision processes, particle and laser beam interactions with solids, low temperature plasmas and general plasmas. As these four topics often overlap and merge in numerous fundamental studies and, more importantly applications, SPIG in general serves as a venue for exchanging ideas in the related fields. We hope that this volume will be an important source of information about progress in plasma physics and will be useful, first of all, for students, but also for plasma physics scientists. The Editors would like to thank the invited speakers for their participation at SPIG 2012 and for their efforts writing contributions for this volume. We also express our gratitude to the members of Scientific and Organizing committees for their efforts in organizing this SPIG. Especially we would like to thank the Ministry of Education, Science and Technological Development of Republic of Serbia, Provincial Secretariat for Science and Techonological Development, Province of Vojvodina, Institute Français de Serbie and Biser Zrenjanin for financial support as well as the European Physical Society (EPS) for supporting the award for the best poster of a young scientist and American Elements, USA. Milorad Kuraica Zoran Mijatovic October 2012 Editors
2014-01-01
Introduction The response to exogenous epinephrine (Ep) is difficult to predict given the multitude of factors involved such as broad pharmacokinetic and pharmacodynamic between-subject variabilities, which may be more pronounced in children. We investigated the pharmacokinetics and pharmacodynamics of Ep, co-administered with milrinone, in children who underwent open heart surgical repair for congenital defects following cardiopulmonary bypass, including associated variability factors. Methods Thirty-nine children with a high risk of low cardiac output syndrome were prospectively enrolled. Ep pharmacokinetics, hemodynamic and metabolic effects were analyzed using the non-linear mixed effects modeling software MONOLIX. According to the final model, an Ep dosing simulation was suggested. Results Ep dosing infusions ranged from 0.01 to 0.23 μg.kg-1.min-1 in children whose weight ranged from 2.5 to 58 kg. A one-compartment open model with linear elimination adequately described the Ep concentration-time courses. Bodyweight (BW) was the main covariate influencing clearance (CL) and endogenous Ep production rate (q0) via an allometric relationship: CL(BWi) = θCL x (BWi)3/4 and q0(BWi) = θq0 x (BWi )3/4. The increase in heart rate (HR) and mean arterial pressure (MAP) as a function of Ep concentration were well described using an Emax model. The effect of age was significant on HR and MAP basal level parameters. Assuming that Ep stimulated the production rate of plasma glucose, the increases in plasma glucose and lactate levels were well described by turnover models without any significant effect of age, BW or exogenous glucose supply. Conclusions According to this population analysis, the developmental effects of BW and age explained a part of the pharmacokinetic and pharmacodynamics between-subject variabilities of Ep administration in critically ill children. This approach ultimately leads to a valuable Ep dosing simulation which should help clinicians to determine an appropriate a priori dosing regimen. PMID:24456639
Phase space effects on fast ion transport modeling in tokamaks
NASA Astrophysics Data System (ADS)
Podesta, Mario
2015-11-01
Simulations of burning plasmas require a consistent treatment of energetic particles (EP), possibly including the effects of instabilities. Reduced EP transport models are emerging as an effective tool to account for those effects in long time-scale simulations. Available models essentially differ for the main transport drive, which is associated to gradients in real or phase space. It is crucial to assess to what extent those different assumptions affect computed quantities such as EP profile, Neutral Beam (NB) driven current and energy/momentum transfer to the thermal populations. These issues are investigated through a kick model, which includes modifications of the EP distribution by instabilities in real and velocity space. TRANSP simulations including the kick model are applied to NB-heated NSTX discharges featuring unstable toroidal Alfvén eigenmodes (TAEs). Results show that TAEs mainly affect fast ions with large parallel velocity, i.e. the most effective for NB current drive. Other portions of the EP distribution are nearly unperturbed. Core NB driven current decreases by 10-30%, with even larger relative changes toward the plasma edge. When TAEs evolve in so-called avalanches, the model reproduces measured drops of ~ 10% in the neutron rate. Consistently with previous results, the drop is caused by both EP energy loss and EP redistribution. These results are compared to those from a simple diffusive model and a ``critical gradient'' model, which postulates radial EP gradient as the only transport drive. The importance of EP velocity space modifications is discussed in terms of accuracy of the predictions, with emphasis on Neutral Beam driven current. Work supported by U.S. DOE Contract DE-AC02-09CH11466.
Antiobesity Effect of Exopolysaccharides Isolated from Kefir Grains.
Lim, Juha; Kale, Madhuvanti; Kim, Dong-Hyeon; Kim, Hong-Seok; Chon, Jung-Whan; Seo, Kun-Ho; Lee, Hyeon Gyu; Yokoyama, Wallace; Kim, Hyunsook
2017-11-22
Physiological properties of water-soluble exopolysaccharides (EPS) and residues after EPS removal (Res) from the probiotic kefir were determined in high-fat (HF) diet-fed C57BL/6J mice. EPS solutions showed rheological properties and lower viscosity compared to those of β-glucan (BG). EPS significantly suppressed the adipogenesis of 3T3-L1 preadipocytes in a dose-dependent manner. Mice were fed HF diets containing 5% EPS, 5% BG, 8% Res, or 5% microcrystalline cellulose (control) for 4 weeks. Compared with the control, EPS supplementation significantly reduced HF diet-induced body weight gain, adipose tissue weight, and plasma very-low-density lipoprotein cholesterol concentration (P < 0.05). Res and BG significantly reduced body weight gain; however, reduction in adipose tissue weight was not statistically significant, suggesting that the antiobesity effect of EPS occurs due to viscosity and an additional factor. EPS supplementation significantly enhanced abundance of Akkermansia spp. in feces. These data indicate that EPS shows significant antiobesity effects possibly via intestinal microbiota alterations.
Browning, A J; Butt, W R; Lynch, S S; Shakespear, R A; Crawford, J S
1983-12-01
Maternal venous plasma concentrations of beta-LPH, beta-EP and gamma-LPH were compared in (i) patients undergoing vaginal delivery, 11 with an epidural block and 13 with pethidine and nitrous oxide or no analgesics; (ii) patients delivered by caesarean section, 7 under epidural block and 8 under general anaesthesia. Patients delivered by either method under epidural block had significantly lower levels of all three peptides than those receiving no epidural. There were significant negative correlations between umbilical vein beta-LPH, beta-EP and gamma-LPH concentrations and umbilical artery pH and positive correlations between beta-LPH and beta-EP but not gamma-LPH and cord PCO2 in 29 patients. There was no relation between cord levels of any of the three peptides and the method of analgesia or the route of delivery. Although concentrations of all three peptides were closely correlated to one another in either maternal or cord plasma, there was no relationship between maternal and fetal levels.
Enhancer Sharing Promotes Neighborhoods of Transcriptional Regulation Across Eukaryotes
Quintero-Cadena, Porfirio; Sternberg, Paul W.
2016-01-01
Enhancers physically interact with transcriptional promoters, looping over distances that can span multiple regulatory elements. Given that enhancer–promoter (EP) interactions generally occur via common protein complexes, it is unclear whether EP pairing is predominantly deterministic or proximity guided. Here, we present cross-organismic evidence suggesting that most EP pairs are compatible, largely determined by physical proximity rather than specific interactions. By reanalyzing transcriptome datasets, we find that the transcription of gene neighbors is correlated over distances that scale with genome size. We experimentally show that nonspecific EP interactions can explain such correlation, and that EP distance acts as a scaling factor for the transcriptional influence of an enhancer. We propose that enhancer sharing is commonplace among eukaryotes, and that EP distance is an important layer of information in gene regulation. PMID:27799341
Effects of laser-plasma instabilities on hydro evolution in an OMEGA-EP long-scale-length experiment
Li, J.; Hu, S. X.; Ren, C.
2017-02-28
Laser-plasma instabilities and hydro evolution of the coronal plasma in an OMEGA EP long-scale-length experiment with planar targets were studied with particle-in-cell (PIC) and hydrodynamic simulations. Plasma and laser conditions were first obtained in a two-dimensional DRACO hydro simulation with only inverse-bremsstrahlung absorption. Using these conditions, an OSIRIS PIC simulation was performed to study laser absorption and hot-electron generation caused by laser-plasma instabilities (LPIs) near the quarter-critical region. The obtained PIC information was subsequently coupled to another DRACO simulation to examine how the LPIs affect the overall hydrodynamics. Lastly, the results showed that the LPI-induced laser absorption increased the electronmore » temperature but did not significantly change the density scale length in the corona.« less
Effects of laser-plasma instabilities on hydro evolution in an OMEGA-EP long-scale-length experiment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, J.; Hu, S. X.; Ren, C.
Laser-plasma instabilities and hydro evolution of the coronal plasma in an OMEGA EP long-scale-length experiment with planar targets were studied with particle-in-cell (PIC) and hydrodynamic simulations. Plasma and laser conditions were first obtained in a two-dimensional DRACO hydro simulation with only inverse-bremsstrahlung absorption. Using these conditions, an OSIRIS PIC simulation was performed to study laser absorption and hot-electron generation caused by laser-plasma instabilities (LPIs) near the quarter-critical region. The obtained PIC information was subsequently coupled to another DRACO simulation to examine how the LPIs affect the overall hydrodynamics. Lastly, the results showed that the LPI-induced laser absorption increased the electronmore » temperature but did not significantly change the density scale length in the corona.« less
Thomson, Kerry A; Haberer, Jessica E; Marzinke, Mark A; Mujugira, Andrew; Hendrix, Craig W; Celum, Connie; Ndase, Patrick; Ronald, Allan; Bangsberg, David R; Baeten, Jared M
2017-06-01
Sharing of pre-exposure prophylaxis (PrEP) medications is a concern for PrEP implementation. For HIV-1 serodiscordant couples, sharing may undermine the HIV-1 prevention benefit and also cause antiretroviral resistance if taken by HIV-1 infected partners. Within a PrEP efficacy trial among HIV-1 serodiscordant couples, we assessed the occurrence of PrEP sharing by self-report and plasma tenofovir concentrations in HIV-1 infected partners. PrEP sharing was self-reported at <0.01% of visits, and 0%-1.6% of randomly selected and 0% of purposively selected specimens from HIV-1 infected participants had detectable tenofovir concentrations (median: 66.5 ng/mL, range: 1.3-292 ng/mL). PrEP sharing within HIV-1 serodiscordant couples was extremely rare.
Isolation of Rare Tumor Cells from Blood Cells with Buoyant Immuno-Microbubbles
Shi, Guixin; Cui, Wenjin; Benchimol, Michael; Liu, Yu-Tsueng; Mattrey, Robert F.; Mukthavaram, Rajesh; Kesari, Santosh; Esener, Sadik C.; Simberg, Dmitri
2013-01-01
Circulating tumor cells (CTCs) are exfoliated at various stages of cancer, and could provide invaluable information for the diagnosis and prognosis of cancers. There is an urgent need for the development of cost-efficient and scalable technologies for rare CTC enrichment from blood. Here we report a novel method for isolation of rare tumor cells from excess of blood cells using gas-filled buoyant immuno-microbubbles (MBs). MBs were prepared by emulsification of perfluorocarbon gas in phospholipids and decorated with anti-epithelial cell adhesion molecule (EpCAM) antibody. EpCAM-targeted MBs efficiently (85%) and rapidly (within 15 minutes) bound to various epithelial tumor cells suspended in cell medium. EpCAM-targeted MBs efficiently (88%) isolated frequent tumor cells that were spiked at 100,000 cells/ml into plasma-depleted blood. Anti-EpCAM MBs efficiently (>77%) isolated rare mouse breast 4T1, human prostate PC-3 and pancreatic cancer BxPC-3 cells spiked into 1, 3 and 7 ml (respectively) of plasma-depleted blood. Using EpCAM targeted MBs CTCs from metastatic cancer patients were isolated, suggesting that this technique could be developed into a valuable clinical tool for isolation, enumeration and analysis of rare cells. PMID:23516425
Simulation of Chirping Avalanche in Neighborhood of TAE gap
NASA Astrophysics Data System (ADS)
Berk, Herb; Breizman, Boris; Wang, Ge; Zheng, Linjin
2016-10-01
A new kinetic code, CHIRP, focuses on the nonlinear response of resonant energetic particles (EPs) that destabilize Alfven waves which then can produce hole and clump phase space chirping structures, while the background plasma currents are assumed to respond linearly to the generated fields. EP currents are due to the motion arising from the perturbed field that is time averaged over an equilibrium orbit. A moderate EP source produces TAE chirping structures that have a limited range of chirping that do not reach the continuum. When the source is sufficiently strong, an EPM is excited in the lower continuum and it chirps rapidly downward as its amplitude rapidly grows in time. This response resembles the experimental observation of an avalanche, which occurs after a series of successive chirping events with a modest frequency shift, and then suddenly a rapid large amplitude and rapid frequency burst to low frequency with the loss of EPs. From these simulation observations we propose that in the experiment the EP population is slowly increasing to the point where the EPM is eventually excited. Supported by SCIDAC Center for Nonlinear Simulation of Energetic Particles Burning Plasmas (CSEP).
Shock-Wave Acceleration of Protons on OMEGA EP
NASA Astrophysics Data System (ADS)
Haberberger, D.; Froula, D. H.; Pak, A.; Link, A.; Patel, P.; Fiuza, F.; Tochitsky, S.; Joshi, C.
2015-11-01
Recent experimental results using shock-wave acceleration (SWA) driven by a CO2 laser in a H2 gas-jet plasma have shown the possibility of producing proton beams with energy spreads <10% and with energies of up to 20 MeV using a modest peak laser power of 4 TW. Here we propose the investigation of the scaling of the SWA mechanism to higher laser powers using the 1- μm OMEGA EP Laser System at the Laboratory for Laser Energetics. The required tailored plasma profile is created by expanding a CH target using the thermal x-ray emission from a UV ablated material. The desired characteristics optimal for SWA are met: (a) peak plasma density is overcritical for the 1- μm main pulse and (b) the plasma profile exponentially decays over a long scale length on the rear side. Results will be shown using a 4 ω probe to experimentally characterize the plasma density profile. Scaling from simulations of the SWA mechanism shows that ion energies in the range of 100 MeV/amu are achievable with a focused a0 of 5 from the OMEGA EP Laser System. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.
Cells exposed to nanosecond electrical pulses exhibit biomarkers of mechanical stress
NASA Astrophysics Data System (ADS)
Roth, Caleb C.; Barnes, Ronald A.; Ibey, Bennett L.; Beier, Hope T.; Moen, Erick K.; Glickman, Randolph D.
2015-03-01
Exposure of cells to very short (<1 μs) electric pulses in the megavolt/meter range have been shown to cause disruption of the plasma membrane. This disruption is often characterized by the formation of numerous small pores (<2 nm in diameter) in the plasma membrane that last for several minutes, allowing the flow of ions into the cell. These small pores are called nanopores and the resulting damage to the plasma membrane is referred to as nanoporation. Nanosecond electrical pulse (nsEP) exposure can impart many different stressors on a cell, including electrical, electro-chemical, and mechanical stress. Thus, nsEP exposure is not a "clean" insult, making determination of the mechanism of nanoporation quite difficult. We hypothesize that nsEP exposure creates acoustic shock waves capable of causing nanoporation. Microarray analysis of primary adult human dermal fibroblasts (HDFa) exposed to nsEP, indicated several genes associated with mechanical stress were selectively upregulated 4 h post exposure. The idea that nanoporation is caused by external mechanical force from acoustic shock waves has, to our knowledge, not been investigated. This work will critically challenge the existing paradigm that nanoporation is caused solely by an electric-field driven event and could provide the basis for a plausible explanation for electroporation.
Lead Optimization Studies of Cinnamic Amide EP2 Antagonists
2015-01-01
Prostanoid receptor EP2 can play a proinflammatory role, exacerbating disease pathology in a variety of central nervous system and peripheral diseases. A highly selective EP2 antagonist could be useful as a drug to mitigate the inflammatory consequences of EP2 activation. We recently identified a cinnamic amide class of EP2 antagonists. The lead compound in this class (5d) displays anti-inflammatory and neuroprotective actions. However, this compound exhibited moderate selectivity to EP2 over the DP1 prostanoid receptor (∼10-fold) and low aqueous solubility. We now report compounds that display up to 180-fold selectivity against DP1 and up to 9-fold higher aqueous solubility than our previous lead. The newly developed compounds also display higher selectivity against EP4 and IP receptors and a comparable plasma pharmacokinetics. Thus, these compounds are useful for proof of concept studies in a variety of models where EP2 activation is playing a deleterious role. PMID:24773616
Krembs, Christopher; Eicken, Hajo; Deming, Jody W.
2011-01-01
The physical properties of Arctic sea ice determine its habitability. Whether ice-dwelling organisms can change those properties has rarely been addressed. Following discovery that sea ice contains an abundance of gelatinous extracellular polymeric substances (EPS), we examined the effects of algal EPS on the microstructure and salt retention of ice grown from saline solutions containing EPS from a culture of the sea-ice diatom, Melosira arctica. We also experimented with xanthan gum and with EPS from a culture of the cold-adapted bacterium Colwellia psychrerythraea strain 34H. Quantitative microscopic analyses of the artificial ice containing Melosira EPS revealed convoluted ice-pore morphologies of high fractal dimension, mimicking features found in EPS-rich coastal sea ice, whereas EPS-free (control) ice featured much simpler pore geometries. A heat-sensitive glycoprotein fraction of Melosira EPS accounted for complex pore morphologies. Although all tested forms of EPS increased bulk ice salinity (by 11–59%) above the controls, ice containing native Melosira EPS retained the most salt. EPS effects on ice and pore microstructure improve sea ice habitability, survivability, and potential for increased primary productivity, even as they may alter the persistence and biogeochemical imprint of sea ice on the surface ocean in a warming climate. PMID:21368216
Krembs, Christopher; Eicken, Hajo; Deming, Jody W
2011-03-01
The physical properties of Arctic sea ice determine its habitability. Whether ice-dwelling organisms can change those properties has rarely been addressed. Following discovery that sea ice contains an abundance of gelatinous extracellular polymeric substances (EPS), we examined the effects of algal EPS on the microstructure and salt retention of ice grown from saline solutions containing EPS from a culture of the sea-ice diatom, Melosira arctica. We also experimented with xanthan gum and with EPS from a culture of the cold-adapted bacterium Colwellia psychrerythraea strain 34H. Quantitative microscopic analyses of the artificial ice containing Melosira EPS revealed convoluted ice-pore morphologies of high fractal dimension, mimicking features found in EPS-rich coastal sea ice, whereas EPS-free (control) ice featured much simpler pore geometries. A heat-sensitive glycoprotein fraction of Melosira EPS accounted for complex pore morphologies. Although all tested forms of EPS increased bulk ice salinity (by 11-59%) above the controls, ice containing native Melosira EPS retained the most salt. EPS effects on ice and pore microstructure improve sea ice habitability, survivability, and potential for increased primary productivity, even as they may alter the persistence and biogeochemical imprint of sea ice on the surface ocean in a warming climate.
Hatano, Hiroyu; Bacon, Oliver; Rutishauser, Rachel; Kearney, Mary F.; Anderson, Elizabeth M.; Cohen, Stephanie E.; Abdel-Mohsen, Mohamed; Pohlmeyer, Christopher W.; Hoh, Rebecca; McCune, Joseph M.; Spindler, Jonathan; Thanh, Cassandra; Gibson, Erica A.; Kuritzkes, Daniel R.; Siliciano, Robert F.; Price, Richard W.; Liegler, Teri
2017-01-01
Background It is unknown if extremely early initiation of antiretroviral therapy (ART) may lead to long-term ART-free HIV remission or cure. As a result, we studied 2 individuals recruited from a pre-exposure prophylaxis (PrEP) program who started prophylactic ART an estimated 10 days (Participant A; 54-year-old male) and 12 days (Participant B; 31-year-old male) after infection with peak plasma HIV RNA of 220 copies/mL and 3,343 copies/mL, respectively. Extensive testing of blood and tissue for HIV persistence was performed, and PrEP Participant A underwent analytical treatment interruption (ATI) following 32 weeks of continuous ART. Methods and findings Colorectal and lymph node tissues, bone marrow, cerebral spinal fluid (CSF), plasma, and very large numbers of peripheral blood mononuclear cells (PBMCs) were obtained longitudinally from both participants and were studied for HIV persistence in several laboratories using molecular and culture-based detection methods, including a murine viral outgrowth assay (mVOA). Both participants initiated PrEP with tenofovir/emtricitabine during very early Fiebig stage I (detectable plasma HIV-1 RNA, antibody negative) followed by 4-drug ART intensification. Following peak viral loads, both participants experienced full suppression of HIV-1 plasma viremia. Over the following 2 years, no further HIV could be detected in blood or tissue from PrEP Participant A despite extensive sampling from ileum, rectum, lymph nodes, bone marrow, CSF, circulating CD4+ T cell subsets, and plasma. No HIV was detected from tissues obtained from PrEP Participant B, but low-level HIV RNA or DNA was intermittently detected from various CD4+ T cell subsets. Over 500 million CD4+ T cells were assayed from both participants in a humanized mouse outgrowth assay. Three of 8 mice infused with CD4+ T cells from PrEP Participant B developed viremia (50 million input cells/surviving mouse), but only 1 of 10 mice infused with CD4+ T cells from PrEP Participant A (53 million input cells/mouse) experienced very low level viremia (201 copies/mL); sequence confirmation was unsuccessful. PrEP Participant A stopped ART and remained aviremic for 7.4 months, rebounding with HIV RNA of 36 copies/mL that rose to 59,805 copies/mL 6 days later. ART was restarted promptly. Rebound plasma HIV sequences were identical to those obtained during acute infection by single-genome sequencing. Mathematical modeling predicted that the latent reservoir size was approximately 200 cells prior to ATI and that only around 1% of individuals with a similar HIV burden may achieve lifelong ART-free remission. Furthermore, we observed that lymphocytes expressing the tumor marker CD30 increased in frequency weeks to months prior to detectable HIV-1 RNA in plasma. This study was limited by the small sample size, which was a result of the rarity of individuals presenting during hyperacute infection. Conclusions We report HIV relapse despite initiation of ART at one of the earliest stages of acute HIV infection possible. Near complete or complete loss of detectable HIV in blood and tissues did not lead to indefinite ART-free HIV remission. However, the small numbers of latently infected cells in individuals treated during hyperacute infection may be associated with prolonged ART-free remission. PMID:29112956
Magnetic flux pile-up and ion heating in a current sheet formed by colliding magnetized plasma flows
NASA Astrophysics Data System (ADS)
Suttle, L.; Hare, J.; Lebedev, S.; Ciardi, A.; Loureiro, N.; Niasse, N.; Burdiak, G.; Clayson, T.; Lane, T.; Robinson, T.; Smith, R.; Stuart, N.; Suzuki-Vidal, F.
2017-10-01
We present data from experiments carried out at the Magpie pulsed power facility, which show the detailed structure of the interaction of counter-streaming magnetized plasma flows. In our quasi-2D setup, continuous supersonic flows are produced with strong embedded magnetic fields of opposing directions. Their interaction leads to the formation of a dense and long-lasting current sheet, where we observe the pile-up of the magnetic flux at the sheet boundary, as well as the annihilation of field inside, accompanied by an increase in plasma temperature. Spatially resolved measurements with Faraday rotation polarimetry, B-dot probes, XUV imaging, Thomson scattering and laser interferometry diagnostics show the detailed distribution of the magnetic field and other plasma parameters throughout the system. This work was supported in part by the Engineering and Physical Sciences Research Council (EPSRC) Grant No. EP/G001324/1, and by the U.S. Department of Energy (DOE) Awards No. DE-F03-02NA00057 and No. DE-SC-0001063.
New Reactor Physics Benchmark Data in the March 2012 Edition of the IRPhEP Handbook
DOE Office of Scientific and Technical Information (OSTI.GOV)
John D. Bess; J. Blair Briggs; Jim Gulliford
2012-11-01
The International Reactor Physics Experiment Evaluation Project (IRPhEP) was established to preserve integral reactor physics experimental data, including separate or special effects data for nuclear energy and technology applications. Numerous experiments that have been performed worldwide, represent a large investment of infrastructure, expertise, and cost, and are valuable resources of data for present and future research. These valuable assets provide the basis for recording, development, and validation of methods. If the experimental data are lost, the high cost to repeat many of these measurements may be prohibitive. The purpose of the IRPhEP is to provide an extensively peer-reviewed set ofmore » reactor physics-related integral data that can be used by reactor designers and safety analysts to validate the analytical tools used to design next-generation reactors and establish the safety basis for operation of these reactors. Contributors from around the world collaborate in the evaluation and review of selected benchmark experiments for inclusion in the International Handbook of Evaluated Reactor Physics Benchmark Experiments (IRPhEP Handbook) [1]. Several new evaluations have been prepared for inclusion in the March 2012 edition of the IRPhEP Handbook.« less
Status and Perspectives of Electric Propulsion in Italy
NASA Astrophysics Data System (ADS)
Svelto, F.; Marcuccio, S.; Matticari, G.
2002-01-01
Electric Propulsion (EP) is recognized as one of today's enabling technologies for scientific and commercial missions. In consideration of EP's major strategic impact on the near and long term scenarios, an EP development programme has been established within the Italian Space Agency (ASI), aimed at the development of a variety of propulsion capabilities covering different fields of application. This paper presents an overview of Electric Propulsion (EP) activities underway in Italy and outlines the planned development lines, both in research institutions and in industry. Italian EP activities are essentially concentrated in Pisa, at Centrospazio and Alta, and in Florence, at LABEN - Proel Tecnologie Division (LABEN/Proel). Centrospazio/Alta and LABEN/Proel have established a collaboration program for joint advanced developments in the EP field. Established in 1989, Centrospazio is a private research center closely related to the Department of Aerospace Engineering of Pisa University. Along the years, Centrospazio lines of development have included arcjets, magneto- plasma-dynamic thrusters, FEEP and Hall thrusters, as well as computational plasma dynamics and low-thrust mission studies. Alta, a small enterprise, was founded in 1999 to exploit in an industrial setting the results of research previously carried out at Centrospazio. Alta's activities include the development of micronewton and millinewton FEEP thrusters, and testing of high power Hall and ion thrusters in specialised facilities. A full micronewton FEEP propulsion system is being developed for the Microscope spacecraft, a scientific mission by CNES aimed at verification of the Equivalence Principle. FEEP will also fly on ASI's HypSEO, a technological demonstrator for Earth Observation, and is being considered for ESA's GOCE (geodesy) and SMART-2 (formation flying), as well as for the intended scientific spacecraft GG by ASI. The ASI-funded STEPS facility will be placed on an external site on the International Space Station to work as a long-duration testbed for EP systems. ASI co-funds the development of a very large testing facility (5.7 m internal diameter) for high power EP testing up to 50 kW. Proel Tecnologie is a Hi-Tech Organization established in 1986, operating in the field of electron (EGA for the TSS- 1and TSS-1R missions), ion and plasma sources for space applications. The Company, become a Division of LABEN S.p.A. (FINMECCANICA Company co-ordinated by Alenia Spazio) since 1995, has identified in the EP the main strategic development line. LABEN/Proel activities include the development of an Ion Thruster in the millinewton range (RMT, ASI technology contract), cathodes/neutralizers for EP in the 0,2-5 kW power range, in- flight diagnostics of EP sub-systems (ARTEMIS, STENTOR, SMART-1), xenon feedlines and flow control units, plasma contactors for the electrostatic charge control on spacecrafts (PLEGPAY experiment on the ISS) and support technologies/facilities for the manufacturing of Hall Thrusters and propellant tanks (the latter by using an advanced process for composite materials polymerization through electron beam irradiation). ASI considers EP development as a National priority and various technology activities are under evaluation. In this context, the Agency is playing a continued role in the process of exploitation of Italian experience and capability and in harmonisation with European efforts in the field.
Abrahams, Alferso C; Habib, Sayed M; Dendooven, Amélie; Riser, Bruce L; van der Veer, Jan Willem; Toorop, Raechel J; Betjes, Michiel G H; Verhaar, Marianne C; Watson, Christopher J E; Nguyen, Tri Q; Boer, Walther H
2014-01-01
Encapsulating peritoneal sclerosis (EPS) is a devastating complication of peritoneal dialysis (PD). The pathogenesis is not exactly known and no preventive strategy or targeted medical therapy is available. CCN2 has both pro-fibrotic and pro-angiogenic actions and appears an attractive target. Therefore, we studied peritoneal expression of CCN2, as well as TGFβ1 and VEGF, in different stages of peritoneal fibrosis. Sixteen PD patients were investigated and compared to 12 hemodialysis patients and four pre-emptively transplanted patients. Furthermore, expression was investigated in 12 EPS patients in comparison with 13 PD and 12 non-PD patients without EPS. Peritoneal tissue was taken during kidney transplantation procedure or during EPS surgery. In a subset of patients, CCN2 protein levels in peritoneal effluent and plasma were determined. Samples were examined by qPCR, histology, immunohistochemistry, and ELISA. Peritoneal CCN2 expression was 5-fold higher in PD patients compared to pre-emptively transplanted patients (P < 0.05), but did not differ from hemodialysis patients. Peritoneal expression of TGFβ1 and VEGF were not different between the three groups; neither was peritoneal thickness. Peritoneum of EPS patients exhibited increased expression of CCN2 (35-fold, P < 0.001), TGFβ1 (24-fold, P < 0.05), and VEGF (77-fold, P < 0.001) compared to PD patients without EPS. In EPS patients, CCN2 protein was mainly localized in peritoneal endothelial cells and fibroblasts. CCN2 protein levels were significantly higher in peritoneal effluent of EPS patients compared to levels in dialysate of PD patients (12.0 ± 4.5 vs. 0.91 ± 0.92 ng/ml, P < 0.01), while plasma CCN2 levels were not increased. Peritoneal expression of CCN2, TGFβ1, and VEGF are significantly increased in EPS patients. In early stages of peritoneal fibrosis, only CCN2 expression is slightly increased. Peritoneal CCN2 overexpression in EPS patients is a locally driven response. The potential of CCN2 as biomarker and target for CCN2-inhibiting agents to prevent or treat EPS warrants further study.
Abrahams, Alferso C.; Habib, Sayed M.; Dendooven, Amélie; Riser, Bruce L.; van der Veer, Jan Willem; Toorop, Raechel J.; Betjes, Michiel G. H.; Verhaar, Marianne C.; Watson, Christopher J. E.; Nguyen, Tri Q.; Boer, Walther H.
2014-01-01
Introduction Encapsulating peritoneal sclerosis (EPS) is a devastating complication of peritoneal dialysis (PD). The pathogenesis is not exactly known and no preventive strategy or targeted medical therapy is available. CCN2 has both pro-fibrotic and pro-angiogenic actions and appears an attractive target. Therefore, we studied peritoneal expression of CCN2, as well as TGFβ1 and VEGF, in different stages of peritoneal fibrosis. Materials and methods Sixteen PD patients were investigated and compared to 12 hemodialysis patients and four pre-emptively transplanted patients. Furthermore, expression was investigated in 12 EPS patients in comparison with 13 PD and 12 non-PD patients without EPS. Peritoneal tissue was taken during kidney transplantation procedure or during EPS surgery. In a subset of patients, CCN2 protein levels in peritoneal effluent and plasma were determined. Samples were examined by qPCR, histology, immunohistochemistry, and ELISA. Results Peritoneal CCN2 expression was 5-fold higher in PD patients compared to pre-emptively transplanted patients (P<0.05), but did not differ from hemodialysis patients. Peritoneal expression of TGFβ1 and VEGF were not different between the three groups; neither was peritoneal thickness. Peritoneum of EPS patients exhibited increased expression of CCN2 (35-fold, P<0.001), TGFβ1 (24-fold, P<0.05), and VEGF (77-fold, P<0.001) compared to PD patients without EPS. In EPS patients, CCN2 protein was mainly localized in peritoneal endothelial cells and fibroblasts. CCN2 protein levels were significantly higher in peritoneal effluent of EPS patients compared to levels in dialysate of PD patients (12.0±4.5 vs. 0.91±0.92 ng/ml, P<0.01), while plasma CCN2 levels were not increased. Conclusions Peritoneal expression of CCN2, TGFβ1, and VEGF are significantly increased in EPS patients. In early stages of peritoneal fibrosis, only CCN2 expression is slightly increased. Peritoneal CCN2 overexpression in EPS patients is a locally driven response. The potential of CCN2 as biomarker and target for CCN2-inhibiting agents to prevent or treat EPS warrants further study. PMID:25384022
Study of energetic particle physics with advanced ECEI system on the HL-2A tokamak
NASA Astrophysics Data System (ADS)
Shi, Zhongbing; Jiang, Min; Yu, Liming; Chen, Wei; Shi, Peiwan; Zhong, Wulyu; Yang, Zengchen; Zhang, Boyu; Ji, Xiaoquan; Li, Yonggao; Zhou, Yan; Song, Shaodong; Huang, Mei; Song, Xianming; Li, Jiaxuan; Yuan, Baoshan; Fu, Bingzhong; Liu, Zetian; Ding, Xuantong; Xu, Yuhong; Yang, Qingwei; Duan, Xuru
2017-07-01
Understanding the physics of energetic particles (EP) is crucial for the burning plasmas in next generation fusion devices such as ITER. In this work, three types of internal kink modes (a saturated internal kink mode (SK), a resonant internal kink mode (RK), and a double e-fishbone) excited by energetic particles in the low density discharges during ECRH/ECCD heating have been studied by the newly developed 24(poloidal) × 16(radial) = 384 channel ECEI system on the HL-2A tokamak. The SK and RK rotate in the electron diamagnetic direction poloidally and are destabilized by the energetic trapped electrons. The SK is destabilized in the case of qmin > 1, while the RK is destabilized in the case of qmin < 1. The double e-fishbone, which has two m/n = 1/1 modes propagating in the opposite directions poloidally, has been observed during plasma current ramp-up with counter-ECCD. Strong thermal transfer and mode coupling between the two m/n = 1/1 modes have been studied.
Browning, A J; Butt, W R; Lynch, S S; Shakespear, R A
1983-12-01
Plasma beta-LPH, beta-EP and gamma-LPH concentrations were measured by radioimmunoassay in 10 pregnant women from 12 weeks gestation until term and in nine women in the early follicular phase of the cycle. There was a progressive and significant rise in the concentration of all three peptides throughout pregnancy and by 32 weeks the concentrations of beta-LPH and beta-EP were greater than the corresponding concentrations in the follicular phase: gamma-LPH was greater than in the follicular phase by the end of pregnancy in those women who were delivered after 40 weeks. The ratio of beta-LPH to gamma-LPH did not change significantly throughout pregnancy, but there was a progressive fall in the beta-LPH/beta-EP ratio. The possible presence of a 'big LPH' to explain this finding is discussed.
FY14 LLNL OMEGA Experimental Programs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heeter, R. F.; Fournier, K. B.; Baker, K.
In FY14, LLNL’s High-Energy-Density Physics (HED) and Indirect Drive Inertial Confinement Fusion (ICF-ID) programs conducted several campaigns on the OMEGA laser system and on the EP laser system, as well as campaigns that used the OMEGA and EP beams jointly. Overall these LLNL programs led 324 target shots in FY14, with 246 shots using just the OMEGA laser system, 62 shots using just the EP laser system, and 16 Joint shots using Omega and EP together. Approximately 31% of the total number of shots (62 OMEGA shots, 42 EP shots) shots supported the Indirect Drive Inertial Confinement Fusion Campaign (ICF-ID).more » The remaining 69% (200 OMEGA shots and 36 EP shots, including the 16 Joint shots) were dedicated to experiments for High- Energy-Density Physics (HED). Highlights of the various HED and ICF campaigns are summarized in the following reports.« less
FY15 LLNL OMEGA Experimental Programs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heeter, R. F.; Baker, K. L.; Barrios, M. A.
In FY15, LLNL’s High-Energy-Density Physics (HED) and Indirect Drive Inertial Confinement Fusion (ICF-ID) programs conducted several campaigns on the OMEGA laser system and on the EP laser system, as well as campaigns that used the OMEGA and EP beams jointly. Overall these LLNL programs led 468 target shots in FY15, with 315 shots using just the OMEGA laser system, 145 shots using just the EP laser system, and 8 Joint shots using Omega and EP together. Approximately 25% of the total number of shots (56 OMEGA shots and 67 EP shots, including the 8 Joint shots) supported the Indirect Drivemore » Inertial Confinement Fusion Campaign (ICF-ID). The remaining 75% (267 OMEGA shots and 86 EP shots) were dedicated to experiments for High-Energy-Density Physics (HED). Highlights of the various HED and ICF campaigns are summarized in the following reports.« less
Design and installation of a ferromagnetic wall in tokamak geometry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hughes, P. E., E-mail: peh2109@columbia.edu; Levesque, J. P.; Rivera, N.
Low-activation ferritic steels are leading material candidates for use in next-generation fusion development experiments such as a prospective component test facility and DEMO power reactor. Understanding the interaction of plasmas with a ferromagnetic wall will provide crucial physics for these facilities. In order to study ferromagnetic effects in toroidal geometry, a ferritic wall upgrade was designed and installed in the High Beta Tokamak–Extended Pulse (HBT-EP). Several material options were investigated based on conductivity, magnetic permeability, vacuum compatibility, and other criteria, and the material of choice (high-cobalt steel) is characterized. Installation was accomplished quickly, with minimal impact on existing diagnostics andmore » overall machine performance, and initial results demonstrate the effects of the ferritic wall on plasma stability.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saeed, Noha M.; El-Demerdash, Ebtehal; Abdel-Rahman, Hanaa M.
Methyl palmitate (MP) and ethyl palmitate (EP) are naturally occurring fatty acid esters reported as inflammatory cell inhibitors. In the current study, the potential anti-inflammatory activity of MP and EP was evaluated in different experimental rat models. Results showed that MP and EP caused reduction of carrageenan-induced rat paw edema in addition to diminishing prostaglandin E2 (PGE2) level in the inflammatory exudates. In lipopolysaccharide (LPS)-induced endotoxemia in rats, MP and EP reduced plasma levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). MP and EP decreased NF-κB expression in liver and lung tissues and ameliorated histopathological changes caused by LPS.more » Topical application of MP and EP reduced ear edema induced by croton oil in rats. In the same animal model, MP and EP reduced neutrophil infiltration, as indicated by decreased myeloperoxidase (MPO) activity. In conclusion, this study demonstrates the effectiveness of MP and EP in combating inflammation in several experimental models. -- Highlights: ► Efficacy of MP and EP in combating inflammation was displayed in several models. ► MP and EP reduced carrageenan-induced rat paw edema and prostaglandin E2 level. ► MP and EP decreased TNF-α and IL-6 levels in experimental endotoxemia. ► MP and EP reduced NF-κB expression and histological changes in rat liver and lung. ► MP and EP reduced croton oil-induced ear edema and neutrophil infiltration.« less
Wei, Liang-Liang; Wang, Kun; Zhao, Qing-Liang; Jiang, Jun-Qiu; Kong, Xiang-Juan; Lee, Duu-Jong
2012-09-15
Correlation between fractional, biodegradable and spectral characteristics of sludge extracellular polymeric substances (EPS) by different protocols has not been well established. This work extracted sludge EPS using alkaline extractants (NH₄OH and formaldehyde + NaOH) and physical protocols (ultrasonication, heating at 80 °C or cation exchange resin (CER)) and then fractionated the extracts using XAD-8/XAD-4 resins. The alkaline extractants yielded more sludge EPS than the physical protocols. However, the physical protocols extracted principally the hydrophilic components which were readily biodegradable by microorganisms. The alkaline extractants dissolved additional humic-like substances from sludge solids which were refractory in nature. Different extraction protocols preferably extracted EPS with distinct fractional, biodegradable and spectral characteristics which could be applied in specific usages. Copyright © 2012 Elsevier Ltd. All rights reserved.
Destabilization of low-n peeling modes by trapped energetic particles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hao, G. Z.; Wang, A. K.; Mou, Z. Z.
2013-06-15
The kinetic effect of trapped energetic particles (EPs), arising from perpendicular neutral beam injection, on the stable low-n peeling modes in tokamak plasmas is investigated, through numerical solution of the mode's dispersion relation derived from an energy principle. A resistive-wall peeling mode with m/n=6/1, with m and n being the poloidal and toroidal mode numbers, respectively, is destabilized by trapped EPs as the EPs' pressure exceeds a critical value β{sub c}{sup *}, which is sensitive to the pitch angle of trapped EPs. The dependence of β{sub c}{sup *} on the particle pitch angle is eventually determined by the bounce averagemore » of the mode eigenfunction. Peeling modes with higher m and n numbers can also be destabilized by trapped EPs. Depending on the wall distance, either a resistive-wall peeling mode or an ideal-kink peeling mode can be destabilized by EPs.« less
Theoretical aspects of the equivalence principle
NASA Astrophysics Data System (ADS)
Damour, Thibault
2012-09-01
We review several theoretical aspects of the equivalence principle (EP). We emphasize the unsatisfactory fact that the EP maintains the absolute character of the coupling constants of physics, while general relativity and its generalizations (Kaluza-Klein, …, string theory) suggest that all absolute structures should be replaced by dynamical entities. We discuss the EP-violation phenomenology of dilaton-like models, which is likely to be dominated by the linear superposition of two effects: a signal proportional to the nuclear Coulomb energy, related to the variation of the fine-structure constant, and a signal proportional to the surface nuclear binding energy, related to the variation of the light quark masses. We recall various theoretical arguments (including a recently proposed anthropic argument) suggesting that the EP be violated at a small, but not unmeasurably small level. This motivates the need for improved tests of the EP. These tests are probing new territories in physics that are related to deep, and mysterious, issues in fundamental physics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peebles, J.; Wei, M. S.; Arefiev, A. V.
A series of experiments studying pre-plasma’s effect on electron generation and transport due to a high intensity laser were conducted on the OMEGA-EP laser facility. A controlled pre-plasma was produced in front of an aluminum foil target prior to the arrival of the high intensity short pulse beam. Energetic electron spectra were characterized with magnetic and bremsstrahlung spectrometers. Preplasma and pulse length were shown to have a large impact on the temperature of lower energy, ponderomotive scaling electrons. Furthermore, super-ponderomotive electrons, seen in prior pre-plasma experiments with shorter pulses, were observed without any initial pre-plasma in our experiment. 2D particle-in-cellmore » and radiation-hydrodynamic simulations shed light on and validate these experimental results.« less
Peebles, J.; Wei, M. S.; Arefiev, A. V.; ...
2017-02-02
A series of experiments studying pre-plasma’s effect on electron generation and transport due to a high intensity laser were conducted on the OMEGA-EP laser facility. A controlled pre-plasma was produced in front of an aluminum foil target prior to the arrival of the high intensity short pulse beam. Energetic electron spectra were characterized with magnetic and bremsstrahlung spectrometers. Preplasma and pulse length were shown to have a large impact on the temperature of lower energy, ponderomotive scaling electrons. Furthermore, super-ponderomotive electrons, seen in prior pre-plasma experiments with shorter pulses, were observed without any initial pre-plasma in our experiment. 2D particle-in-cellmore » and radiation-hydrodynamic simulations shed light on and validate these experimental results.« less
Bloch, M; Schmidt, P J; Su, T P; Tobin, M B; Rubinow, D R
1998-06-15
Premenstrual syndrome (PMS) is a cyclic mood disorder, widely believed, yet not conclusively shown, to be of endocrine etiology. This study examines basal levels of several hormones reported, albeit inconsistently, to differ in women with PMS compared with controls. Subjects (10 PMS patients and 10 controls) had their blood drawn for one full menstrual cycle. Subjects' mood and behavioral symptoms were assessed by daily self-ratings and objective ratings. Plasma was assayed for total and free testosterone (T), beta-endorphin (beta-EP), adrenocorticotropic hormone (ACTH), and cortisol. No differences were observed between the PMS and control groups for beta-EP, ACTH, or cortisol. PMS subjects had significantly lower total and free T plasma levels with a blunting of the normal periovulatory peak, a finding that may be epiphenomenal to age. This study does not confirm previous reports of abnormalities in plasma levels of either ACTH or beta-EP in women with PMS; it also fails to replicate a previous observation of high free T levels in women with PMS. These results are not supportive of a primary endocrine abnormality in PMS patients.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Yueqiang, E-mail: yueqiang.liu@ccfe.ac.uk; Chapman, I. T.; Graves, J. P.
2014-05-15
A non-perturbative magnetohydrodynamic-kinetic hybrid formulation is developed and implemented into the MARS-K code [Liu et al., Phys. Plasmas 15, 112503 (2008)] that takes into account the anisotropy and asymmetry [Graves et al., Nature Commun. 3, 624 (2012)] of the equilibrium distribution of energetic particles (EPs) in particle pitch angle space, as well as first order finite orbit width (FOW) corrections for both passing and trapped EPs. Anisotropic models, which affect both the adiabatic and non-adiabatic drift kinetic energy contributions, are implemented for both neutral beam injection and ion cyclotron resonant heating induced EPs. The first order FOW correction does notmore » contribute to the precessional drift resonance of trapped particles, but generally remains finite for the bounce and transit resonance contributions, as well as for the adiabatic contributions from asymmetrically distributed passing particles. Numerical results for a 9MA steady state ITER plasma suggest that (i) both the anisotropy and FOW effects can be important for the resistive wall mode stability in ITER plasmas; and (ii) the non-perturbative approach predicts less kinetic stabilization of the mode, than the perturbative approach, in the presence of anisotropy and FOW effects for the EPs. The latter may partially be related to the modification of the eigenfunction of the mode by the drift kinetic effects.« less
NASA Astrophysics Data System (ADS)
Gordillo-Vazquez, F. J.
2009-07-01
The 19th Europhysics Sectional Conference on the Atomic and Molecular Physics of Ionized Gases (ESCAMPIG-2008) took place in Granada (Spain) from 15 to 19 July 2008. The conference was mainly organized by the Spanish National Research Council (CSIC), with the collaboration and support of the University of Córdoba (UCO) and the Research Center for Energy, Environment and Technology (CIEMAT). It is already 35 years since the first ESCAMPIG in 1973. The first editions of ESCAMPIG were in consecutive years (1973 and 1974) but later on it became a biennial conference of the European Physical Society (EPS) initially focusing on the collisional and radiative atomic and molecular processes in low temperature plasmas. The successive ESCAMPIGs took place in Bratislava in 1976 (3rd), Essen in 1978 (4th), Dubrovnik in 1980 (5th) and so on until the last one organized in Granada in 2008 (19th), the first ESCAMPIG in Spain. A number of changes have taken place in the Granada edition of ESCAMPIG. First, the previous six topics that have remained unchanged for almost two decades (since 1990) have now been updated to become twelve new topics which, in the opinion of the International Scientific Committee (ISC), will enhance the opportunity for discussions and communication of new findings and developments in the field of low temperature plasmas. The new list of topics for ESCAMPIG is: • Atomic and molecular processes in plasmas • Transport phenomena, particle velocity distribution function • Physical basis of plasma chemistry • Plasma surface interaction (boundary layers, sheath, surface processes) • Plasma diagnostics • Plasma and dicharges theory and simulation • Self-organization in plasmas, dusty plasmas • Upper atmospheric plasmas and space plasmas • Low pressure plasma sources • High pressure plasma sources • Plasmas and gas flows • Laser produced plasmas Secondly, a new prize has been created, the `William Crookes' prize in Plasma Physics to be awarded biennially to a mid-career (10 to 20 years after PhD) researcher who has been judged to have made major contributions in one or more of the areas covered by ESCAMPIG. The prize was co-sponsored by the ESCAMPIG-2008 local committee, the European Physical Society (EPS) and Plasma Sources Science and Technology. The award was 1,000 Euros and a diploma along with hotel accommodation and waived fees to attend ESCAMPIG-2008 where the award was presented. The first `William Crookes' prize was awarded to Professor Dr Richard Van de Sanden from the Eindhoven University of Technology `for his major contributions to fundamental plasma-wall interaction studies and their use in plasma enhanced deposition and etching'. More than 290 scientists from 35 countries around the world attended ESCAMPIG-2008 in Granada. Also remarkable is the important number of registered students (87) that participated in the conference. The total number of abstracts submitted was over 330 with more than 300 poster presentations in the three scheduled poster sessions. The oral sessions involved 16 invited lectures and eight ISC selected hot topical presentations. In addition, two afternoon special sessions of ESCAMPIG-2008 were devoted to two workshops on: • Sprite chemistry and their impact in the upper atmosphere of the Earth, organized by Dr T Neubert and Dr F J Gordillo-Vazquez • Diagnostics of active species in plasma deposition of thin films, organized by Dr F L Tabarés Following a tradition started in previous ESCAMPIG editions, a special issue of {\\it Plasma Sources Science and Technology} (PSST) is published including peer-reviewed papers based on the invited lectures, hot topic presentations and workshop contributions. Many of the authors agreed to prepare and submit within deadline suitable articles with original results or in the form of reviews and critical overviews of their own published results. I would like to thank all the speakers for their co-operation and efforts in preparing interesting lectures and for preparing papers for the special issue of PSST devoted to ESCAMPIG XIX. These papers are an equilibrated representation of the topics treated during the conference. Their publication in PSST will significantly contribute to giving the contents of ESCAMPIG a wider audience. I would like to thank the International Scientific Committee, chaired by Professor W G Graham, for building up the Scientific Program of ESCAMPIG-2008. Finally, I want to thank the workshop organizers and all the sponsors (public institutions and companies) whose contribution was an essential part of the success of ESCAMPIG 2008 in Granada. F J Gordillo-Vazquez, CSIC, Granada, Spain Guest Editor
Towards a turbulent magnetic dysnamo platform
NASA Astrophysics Data System (ADS)
Flippo, Kirk; Rasmus, Alexander; Li, Hui; Li, Shengtai; Kuranz, Carolyn; Levesque, Joseph; Klein, Sallee; Tzeferacos, Petros
2017-10-01
It is known through astronomical observations that most of the Universe is ionized, magnetized, and often turbulent and filled with jets. One theorized process to create strong magnetic fields and jets is the turbulent magnetic dynamo. The magnetic dynamo is a fundamental process in plasma physics, taking kinetic energy and converting it to magnetic energy and is very important to planetary physics and astrophysics. We report on recent Omega EP experiments to produce platform with a turbulent plume of magnetized material with which to study the turbulent magnetic dynamo process. The laser interaction with the target can seed magnetic fields that can be advected into the plume and amplified to saturation by the turbulent magnetic dynamo process. The experimentally measured plume characteristics are compared to hydro code calculations.
Alkmin, Diego V; Perez-Patiño, Cristina; Barranco, Isabel; Parrilla, Inmaculada; Vazquez, Juan M; Martinez, Emilio A; Rodriguez-Martinez, Heriberto; Roca, Jordi
2014-10-01
Boar bulk ejaculates are now being collected instead of usual sperm-rich fractions (SRF) for artificial insemination purpose. The present study evaluated the influence of holding boar sperm samples before freezing surrounded in their own seminal plasma (SP), from either fractions/portions or the entire ejaculate, on post-thawing sperm quality and functionality. Ejaculates collected as bulk (BE) or as separate (first 10 mL of SRF [P1] and rest of SRF [P2]) from 10 boars were held 24h at 15-17°C and then frozen. Some bulk ejaculate samples were frozen immediately after collections as Control. In addition, epididymal sperm samples from the same 10 boars were collected post-mortem and extended in SP from P1 (EP1), P2 (EP2) and post SRF (EP3), and also held 24h before freezing for a better understanding of the influence of SP on boar sperm cryopreservation. The sperm quality (motility, evaluated by CASA, and viability, evaluated by flow cytometry) and functionality (flow cytometry assessment of plasma membrane fluidity, mitochondrial membrane potential and intracellular generation of reactive oxygen species [ROS] in viable sperm) were evaluated at 30, 150 and 300 min post-thaw. Post-thawing sperm quality and functionality of P1 and P2 were similar but higher (p < 0.01) than BE samples. Control samples showed higher (p < 0.01) post-thaw sperm quality and functionality than BE samples. Post-thawing sperm quality and functionality of EP1 and EP2 were similar but higher (p < 0.05) than EP3. These results showed that boar sperm from BE are more cryosensitive than those from the SRF, particularly when held 24h before freezing, which would be attributable to the cryonegative effects exerted by the SP from post SRF. Copyright © 2014 Elsevier Inc. All rights reserved.
Martinuzzo, Marta E; Duboscq, Cristina; Lopez, Marina S; Barrera, Luis H; Vinuales, Estela S; Ceresetto, Jose; Forastiero, Ricardo R; Oyhamburu, Jose
2018-06-01
Rivaroxaban oral anticoagulant does not need laboratory monitoring, but in some situations plasma level measurement is useful. The objective of this paper was to verify analytical performance and compare two rivaroxaban calibrated anti Xa assays/coagulometer systems with specific or other branch calibrators. In 59 samples drawn at trough or peak from patients taking rivaroxaban, plasma levels were measured by HemosIL Liquid anti Xa in ACLTOP 300/500, and STA liquid Anti Xa in TCoag Destiny Plus. HemosIL and STA rivaroxaban calibrators and controls were used. CLSI guideline procedures EP15A3 for precision and trueness, EP6 for linearity, and EP9 for methods comparison were used. Coefficient of variation within run and total precision (CVR and CVWL respectively) of plasmatic rivaroxaban were < 4.2 and < 4.85% and BIAS < 7.4 and < 6.5%, for HemosIL-ACL TOP and STA-Destiny systems, respectively. Linearity verification 8 - 525 ng/mL a Deming regression for methods comparison presented R 0.963, 0.968 and 0.982, with a mean CV 13.3% when using different systems and calibrations. The analytical performance of plasma rivaroxaban was acceptable in both systems, and results from reagent/coagulometer systems are comparable even when calibrating with different branch material.
Code of Federal Regulations, 2011 CFR
2011-07-01
... All Use Patterns Test Substance MP EP Test Notes Product Chemistry and Composition 885.1100 Product... R TGAI and MP TGAI and EP 2, 3 885.1500 Certification of limits R MP EP -- Physical and Chemical...
Code of Federal Regulations, 2012 CFR
2012-07-01
... All Use Patterns Test Substance MP EP Test Notes Product Chemistry and Composition 885.1100 Product... R TGAI and MP TGAI and EP 2, 3 885.1500 Certification of limits R MP EP -- Physical and Chemical...
Non-thermal equilibrium plasma-liquid interactions with femtolitre droplets
NASA Astrophysics Data System (ADS)
Maguire, Paul; Mahony, Charles; Bingham, Andrew; Patel, Jenish; Rutherford, David; McDowell, David; Mariotti, Davide; Bennet, Euan; Potts, Hugh; Diver, Declan
2014-10-01
Plasma-induced non-equilibrium liquid chemistry is little understood. It depends on a complex interplay of interface and near surface processes, many involving energy-dependent electron-induced reactions and the transport of transient species such as hydrated electrons. Femtolitre liquid droplets, with an ultra-high ratio of surface area to volume, were transported through a low-temperature atmospheric pressure RF microplasma with transit times of 1--10 ms. Under a range of plasma operating conditions, we observe a number of non-equilibrium chemical processes that are dominated by energetic electron bombardment. Gas temperature and plasma parameters (ne ~ 1013 cm-3, Te < 4 eV) were determined while size and droplet velocity profiles were obtained using a microscope coupled to a fast ICCD camera under low light conditions. Laminar mixed-phase droplet flow is achieved and the plasma is seen to significantly deplete only the slower, smaller droplet component due possibly to the interplay between evaporation, Rayleigh instabilities and charge emission. Funding from EPSRC acknowledged (Grants EP/K006088/1 and EP/K006142/1).
Liu, Nai-gang; Guo, Chang-qing; Sun, Hong-mei; Li, Xiao-hong; Wu, Hai-xia; Xu, Hong
2016-04-01
To explore the analgesic mechanism of small knife needle for treating transverse process syndrome of the third vertebra (TPSTV) by observing peripheral and central changesof β-endorphin (β-EP) and enkephalin (ENK) contents. Totally 30 Japanese white big-ear rabbits of clean grade were divided into 5 groups according to random digit table, i.e., the normal control group, the model group, the small knife needle group, the electroacupunture (EA) group, and the small knife needle plus EA group, 6 in each group. The TPSTV model was established by inserting a piece of gelatin sponge into the left transverse process of 3rd lumbar vertebrae. Rabbits in the small knife needlegroup were intervened by small knife needle. Those in the EA group were intervened by EA at bilateralWeizhong (BL40). Those in the small knife needle plus EA group were intervened by small knife needleand EA at bilateral Weizhong (BL40). Contents of β-EP and ENK in plasma, muscle, spinal cord, and hypothalamus were determined after sample collection at day 28 after modeling. Compared with the normal control group, contents of β-EP and ENK in plasma and muscle increased significantly, and contents of β-EP and ENK in spinal cord and hypothalamus decreased significantly in the model group (P < 0.05, P < 0.01). Contents of β-EP and ENK approximated normal levels in the three treatment groups after respective treatment. Compared with the model group, the content of β-EP in muscle decreased, and contents of β-EP and ENK in hypothalamus increased in the three treatment groups after respective treatment (P < 0.05). There were no significant difference among the three treatment groups (P > 0.05). Small knife needle treatment and EA had benign regulation on peripheral and central β-EP and ENK in TPSTV rabbits. Small knife needle treatment showed better effect than that of EA.
Generation and remote delivery of plasma activated species
NASA Astrophysics Data System (ADS)
Maguire, Paul; Mahony, Charles; Kelsey, Colin; Rutherford, David; Mariotti, Davide; Macias-Montero, Manuel; Perez-Martin, Fatima; Diver, Declan
2016-09-01
Plasma interactions with microdroplets offer new opportunities to deliver active chemical agents and nanoparticles to remote substrates downstream with many potential applications from cancer theranostics and wound healing in biomedicine, gentle food decontamination and seed germination in plasma agriculture to catalyst production and photonic structures fabrication, among others. We demonstrate plasma-liquid based pristine nanomaterials synthesis in flight and subsequent delivery up to 120mm from the atmospheric pressure plasma source. Monosized and non-aggregating metal nanoparticles are formed in the rf plasma in less than 100us, representing an increase in precursor reduction rate that is many (>4) orders of magnitude faster than that observed with standard colloidal chemistry or via high energy radiolytic techniques. Also the collection and purification limitations of the latter are avoided. Plasma activated liquid including OH radicals and H2O2 are transported over 120mm and have demonstrated high efficacy bacterial decontamination. These results will be compared with charge species and radical transport from the rf plasma without microdroplets. Reaction models based on high solvated surface electron concentrations will be presented. Funding from EPSRC acknowledged (Grants EP/K006088/1 and EP/K006142/1).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huysmans, G.T.A.; Kerner, W.; Borba, D.
1995-05-01
The active excitation of global Alfven modes using the saddle coils in the Joint European Torus (JET) [{ital Plasma} {ital Physics} {ital and} {ital Controlled} {ital Nuclear} {ital Fusion} {ital Research} 1984, Proceedings of the 10th International Conference, London (International Atomic Energy Agency, Vienna, 1985), Vol. 1, p. 11] as the external antenna, will provide information on the damping of global modes without the need to drive the modes unstable. For the modeling of the Alfven mode excitation, the toroidal resistive magnetohydrodynamics (MHD) code CASTOR (Complex Alfven Spectrum in TORoidal geometry) [18{ital th} {ital EPS} {ital Conference} {ital On} {italmore » Controlled} {ital Fusion} {ital and} {ital Plasma} {ital Physics}, Berlin, 1991, edited by P. Bachmann and D. C. Robinson (The European Physical Society, Petit-Lancy, 1991), Vol. 15, Part IV, p. 89] has been extended to calculate the response to an external antenna. The excitation of a high-performance, high beta JET discharge is studied numerically. In particular, the influence of a finite pressure is investigated. Weakly damped low-{ital n} global modes do exist in the gaps in the continuous spectrum at high beta. A pressure-driven global mode is found due to the interaction of Alfven and slow modes. Its frequency scales solely with the plasma temperature, not like a pure Alfven mode with a density and magnetic field.« less
Theoretical Analysis of the Electron Spiral Toroid Concept
NASA Technical Reports Server (NTRS)
Cambier, Jean-Luc; Micheletti, David A.; Bushnell, Dennis M. (Technical Monitor)
2000-01-01
This report describes the analysis of the Electron Spiral Toroid (EST) concept being promoted by Electron Power Systems Inc. (EPS). The EST is described as a toroidal plasma structure composed Of ion and electron shells. It is claimed that the EST requires little or no external confinement, despite the extraordinarily large energy densities resulting from the self-generating magnetic fields. The present analysis is based upon documentation made available by EPS, a previous description of the model by the Massachusetts Institute of Technology (MIT), and direct discussions with EPS and MIT. It is found that claims of absolute stability and large energy storage capacities of the EST concept have not been substantiated. Notably, it can be demonstrated that the ion fluid is fundamentally unstable. Although various scenarios for ion confinement were subsequently suggested by EPS and MIT, none were found to be plausible. Although the experimental data does not prove the existence of EST configurations, there is undeniable experimental evidence that some type of plasma structures whose characteristics remain to be determined are observed. However, more realistic theoretical models must first be developed to explain their existence and properties before applications of interest to NASA can he assessed and developed.
Cylindrical fast magnetosonic solitary waves in quantum degenerate electron-positron-ion plasma
NASA Astrophysics Data System (ADS)
Abdikian, A.
2018-02-01
The nonlinear properties of fast magnetosonic solitary waves in a quantum degenerate electron-positron (e-p) plasma in the presence of stationary ions for neutralizing the plasma background of bounded cylindrical geometry were studied. By employing the standard reductive perturbation technique and the quantum hydrodynamic model for the e-p fluid, the cylindrical Kadomtsev-Petviashvili (CKP) equation was derived for small, but finite, amplitude waves and was given the solitary wave solution for the parameters relevant to dense astrophysical objects such as white dwarf stars. By a suitable coordinate transformation, the CKP equation can be solved analytically. An analytical solution for magnetosonic solitons and periodic waves is presented. The numerical results reveal that the Bohm potential has a main effect on the periodic and solitary wave structures. By increasing the values of the plasma parameters, the amplitude of the solitary wave will be increased. The present study may be helpful in the understanding of nonlinear electromagnetic soliton waves propagating in both laboratory and astrophysical plasmas, and can help in providing good agreement between theoretical results and laboratory plasma experiments.
Formation of a bifurcated current layer by the collision of supersonic magnetized plasmas
NASA Astrophysics Data System (ADS)
Suttle, Lee; Hare, Jack; Lebedev, Sergey; Ciardi, Andrea; Loureiro, Nuno; Burdiak, Guy; Chittenden, Jerry; Clayson, Thomas; Ma, Jiming; Niasse, Nicolas; Robinson, Timothy; Smith, Roland; Stuart, Nicolas; Suzuki-Vidal, Francisco
2016-10-01
We present detailed experimental data showing the formation and structure of a current layer produced by the collision of two supersonic and well magnetized plasma flows. The pulsed-power driven setup provides two steady and continuous flows, whose embedded magnetic fields mutually annihilate inside the interaction region giving rise to the current layer. Spatially resolved measurements with Faraday rotation polarimetry, Thomson scattering and laser interferometry diagnostics show the detailed distribution of the magnetic field and other plasma parameters throughout the system. We show that the pile-up of magnetic field ahead of the annihilation gives rise to the multi-layered / bi-directional nature of the current sheet, and we discuss pressure balance and energy exchange mechanisms within the system. This work was supported in part by the Engineering and Physical Sciences Research Council (EPSRC) Grant No. EP/G001324/1, and by the U.S. Department of Energy (DOE) Awards No. DE-F03-02NA00057 and No. DE-SC-0001063.
FY16 LLNL Omega Experimental Programs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heeter, R. F.; Ali, S. J.; Benstead, J.
In FY16, LLNL’s High-Energy-Density Physics (HED) and Indirect Drive Inertial Confinement Fusion (ICF-ID) programs conducted several campaigns on the OMEGA laser system and on the EP laser system, as well as campaigns that used the OMEGA and EP beams jointly. Overall, these LLNL programs led 430 target shots in FY16, with 304 shots using just the OMEGA laser system, and 126 shots using just the EP laser system. Approximately 21% of the total number of shots (77 OMEGA shots and 14 EP shots) supported the Indirect Drive Inertial Confinement Fusion Campaign (ICF-ID). The remaining 79% (227 OMEGA shots and 112more » EP shots) were dedicated to experiments for High-Energy-Density Physics (HED). Highlights of the various HED and ICF campaigns are summarized in the following reports. In addition to these experiments, LLNL Principal Investigators led a variety of Laboratory Basic Science campaigns using OMEGA and EP, including 81 target shots using just OMEGA and 42 shots using just EP. The highlights of these are also summarized, following the ICF and HED campaigns. Overall, LLNL PIs led a total of 553 shots at LLE in FY 2016. In addition, LLNL PIs also supported 57 NLUF shots on Omega and 31 NLUF shots on EP, in collaboration with the academic community.« less
Polarimetry diagnostic on OMEGA EP using a 10-ps, 263-nm probe beam.
Davies, A; Haberberger, D; Boni, R; Ivancic, S; Brown, R; Froula, D H
2014-11-01
A polarimetry diagnostic was built and characterized for magnetic-field measurements in laser-plasma experiments on the OMEGA EP laser. This diagnostic was built into the existing 4ω (263-nm) probe system that employs a 10-ps laser pulse collected with an f/4 imaging system. The diagnostic measures the rotation of the probe beam's polarization. The polarimeter uses a Wollaston prism to split the probe beam into orthogonal polarization components. Spatially localized intensity variations between images indicate polarization rotation. Magnetic fields can be calculated by combining the polarimetry data with the measured plasma density profile obtained from angular filter refractometry.
Ni, Yu-Fei; Li, Jun; Wang, Ben-Fu; Jiang, Song-He; Chen, Yi; Zhang, Wei-Feng; Lian, Qing-Quan
2009-10-01
To observe the effect of electroacupuncture (EA) on bispectral index (BIS) and plasma beta-endorphin (beta-EP) level in patients undergoing colonoscopy. Sixty patients were equally randomized into EA group and control group with 30 cases in each. EA (2 Hz/100 Hz, 4-6 V) was applied to the right Zusanli (ST 36) and Shangjuxu (ST 37), and the left Yinlingquan (SP 9), Sanyinjiao (SP 6) and bilateral Hegu (LI 4) respectively 30 min before colonoscopy. The mean arterial pressure (MAP), heart rate (HR) and BIS in two groups were continuously monitored during the study. Plasma beta-EP concentration was detected by radioimmunoassay. The patient's adverse reactions (including pain, satisfaction degree, etc.) were evaluated by visual analog scale (VAS) and verbal stress scale (VSS). Self-comparison showed that MAP and HR in control group increased significantly during colonoscope's splenic flexure passing (P<0.05). Whereas the 2 indexes in EA group had no significant changes during colonoscope insertion, and its splenic flexure passing, hepatic flexure passing and post-enteroscopy (P>0.05). Comparison between two groups showed that MAP at the time-point of colonoscope insertion, and HR at the time-point of colonoscope's splenic flexure passing in EA group were significantly lower than those in control group (P<0.05). BIS values of EA group were significantly lower than those of control group at different time-points after colonoscope insertion (P<0.01). Plasma beta-EP concentrations at the time-points of colonoscope's hepatic flexure passing and post-enteroscopy were evidently increased in both groups in comparison with pre-enteroscopy (P<0.01), and beta-EP was significantly lower in EA group than that in control group at the time-point of colonoscope's hepatic flexure passing (P<0.05). The dosage of Midazolam used for conscious-sedation and the scores of VAS and VSS were also considerably lower in EA group than those in control group (P<0.05, P<0.01). No significant differences were found between two groups in the adverse reactions as dizziness, nausea, vomiting and abdominal pain, but the patients' satisfaction degree in EA group was evidently higher than that in control group (P<0.05). Acupuncture analgesia can effectively lower the colonoscopy patients' BIS value and plasma beta-EP level, meaning attenuation of the patients' stress responses during colonoscopy after EA.
Waltman, Ludo; van Raan, Anthony F J; Smart, Sue
2014-01-01
We investigate the extent to which advances in the health and life sciences (HLS) are dependent on research in the engineering and physical sciences (EPS), particularly physics, chemistry, mathematics, and engineering. The analysis combines two different bibliometric approaches. The first approach to analyze the 'EPS-HLS interface' is based on term map visualizations of HLS research fields. We consider 16 clinical fields and five life science fields. On the basis of expert judgment, EPS research in these fields is studied by identifying EPS-related terms in the term maps. In the second approach, a large-scale citation-based network analysis is applied to publications from all fields of science. We work with about 22,000 clusters of publications, each representing a topic in the scientific literature. Citation relations are used to identify topics at the EPS-HLS interface. The two approaches complement each other. The advantages of working with textual data compensate for the limitations of working with citation relations and the other way around. An important advantage of working with textual data is in the in-depth qualitative insights it provides. Working with citation relations, on the other hand, yields many relevant quantitative statistics. We find that EPS research contributes to HLS developments mainly in the following five ways: new materials and their properties; chemical methods for analysis and molecular synthesis; imaging of parts of the body as well as of biomaterial surfaces; medical engineering mainly related to imaging, radiation therapy, signal processing technology, and other medical instrumentation; mathematical and statistical methods for data analysis. In our analysis, about 10% of all EPS and HLS publications are classified as being at the EPS-HLS interface. This percentage has remained more or less constant during the past decade.
Waltman, Ludo; van Raan, Anthony F. J.; Smart, Sue
2014-01-01
We investigate the extent to which advances in the health and life sciences (HLS) are dependent on research in the engineering and physical sciences (EPS), particularly physics, chemistry, mathematics, and engineering. The analysis combines two different bibliometric approaches. The first approach to analyze the ‘EPS-HLS interface’ is based on term map visualizations of HLS research fields. We consider 16 clinical fields and five life science fields. On the basis of expert judgment, EPS research in these fields is studied by identifying EPS-related terms in the term maps. In the second approach, a large-scale citation-based network analysis is applied to publications from all fields of science. We work with about 22,000 clusters of publications, each representing a topic in the scientific literature. Citation relations are used to identify topics at the EPS-HLS interface. The two approaches complement each other. The advantages of working with textual data compensate for the limitations of working with citation relations and the other way around. An important advantage of working with textual data is in the in-depth qualitative insights it provides. Working with citation relations, on the other hand, yields many relevant quantitative statistics. We find that EPS research contributes to HLS developments mainly in the following five ways: new materials and their properties; chemical methods for analysis and molecular synthesis; imaging of parts of the body as well as of biomaterial surfaces; medical engineering mainly related to imaging, radiation therapy, signal processing technology, and other medical instrumentation; mathematical and statistical methods for data analysis. In our analysis, about 10% of all EPS and HLS publications are classified as being at the EPS-HLS interface. This percentage has remained more or less constant during the past decade. PMID:25360616
Scrape-off-layer currents during MHD activity and disruptions in HBT-EP
NASA Astrophysics Data System (ADS)
Levesque, J. P.; Desanto, S.; Battey, A.; Bialek, J.; Brooks, J. W.; Mauel, M. E.; Navratil, G. A.
2017-10-01
We report scrape-off layer (SOL) current measurements during MHD mode activity and disruptions in the HBT-EP tokamak. Currents are measured via Rogowski coils mounted on tiles in the low-field-side SOL, toroidal jumpers between otherwise-isolated vessel sections, and segmented plasma current Rogowski coils. These currents strongly depend on the plasma's major radius, mode amplitude, and mode phase. Plasma current asymmetries and SOL currents during disruptions reach 4% of the plasma current. Asymmetric toroidal currents between vessel sections rotate at tens of kHz through most of the current quench, then symmetrize once Ip reaches 30% of its pre-disruptive value. Toroidal jumper currents oscillate between co- and counter-Ip, with co-Ip being dominant on average during disruptions. Increases in local plasma current correlate with counter-Ip current in the nearest toroidal jumper. Measurements are interpreted in the context of two models that produce contrary predictions for the toroidal vessel current polarity during disruptions. Plasma current asymmetries are consistent with both models, and scale with plasma displacement toward the wall. Progress of ongoing SOL current diagnostic upgrades is also presented. Supported by U.S. DOE Grant DE-FG02-86ER53222.
External Providers and Their Impact on Primary Physical Education in Aotearoa/New Zealand
ERIC Educational Resources Information Center
Dyson, Ben; Gordon, Barrie; Cowan, Jackie; McKenzie, Allison
2016-01-01
Within Aotearoa/New Zealand primary schools, External Providers (EPs) have steadily increased their influence on physical education. The purpose of this study was to explore and interpret classroom teachers' perspectives of EPs in their primary school. The research team obtained questionnaire responses from 487 classroom teachers from 133…
Aebi, Marcel; Linhart, Susanne; Thun-Hohenstein, Leonhard; Bessler, Cornelia; Steinhausen, Hans-Christoph; Plattner, Belinda
2015-07-01
The objective of the present study was to analyse patterns of emotional, physical and sexual maltreatment in detained male juvenile offenders using latent class analysis (LCA). The association of maltreatment related LCA profiles with psychopathology and criminal behaviors was also studied. LCA based on the items of the Child Trauma Questionnaire (CTQ) assessing childhood emotional, physical, and sexual abuse was performed in a sample of 260 male adolescent offenders (mean age = 16.5 years, SD = 1.29 years). Chi square tests and general linear models were performed to assess the associations of CTQ profiles with categorical interview-based psychiatric disorders, dimensional Youth Self-Report problem scales, and officially registered offenses. LCA suggested a three class solution: (1) a no/mild trauma (NM; 76 %) (2) emotional and physical trauma (EP; 18 %) and (3) emotional, physical, and sexual trauma (EPS; 8 %). The classes EP and EPS were related to a variety of psychiatric disorders and self-reported mental health problems. Furthermore, EPS showed higher presence of a subsequent re-incarceration compared to NM. A majority of sexually abused juveniles also experienced emotional and physical abuse reflecting gravely disturbed family systems. Multiple abuse in childhood was associated with a broad variety of disorders including externalizing disorders and repeated criminal offending. Such findings indicate that trauma assessment is also relevant in externalizing youth. A comprehensive treatment approach for detained boys with multiple abuse experiences is required targeting both mental health needs and the reduction of criminal behaviors.
Desmond, Peter; Best, James P; Morgenroth, Eberhard; Derlon, Nicolas
2018-04-01
The effect of extracellular polymeric substances (EPS) on the meso-scale physical structure and hydraulic resistance of membrane biofilms during gravity driven membrane (GDM) filtration was investigated. Biofilms were developed on the surface of ultrafiltration membranes during dead-end filtration at ultra-low pressure (70 mbar). Biofilm EPS composition (total protein, polysaccharide and eDNA) was manipulated by growing biofilms under contrasting nutrient conditions. Nutrient conditions consisted of (i) a nutrient enriched condition with a nutrient ratio of 100:30:10 (C: N: P), (ii) a phosphorus limitation (C: N: P ratio: 100:30:0), and (iii) a nitrogen limitation (C: N: P ratio: 100:0:10). The structure of the biofilm was characterised at meso-scale using Optical Coherence Tomography (OCT). Biofilm composition was analysed with respect to total organic carbon, total cellular mass and extracellular concentrations of proteins, polysaccharides, and eDNA. 2D-confocal Raman mapping was used to characterise the functional group composition and micro-scale distribution of the biofilms EPS. Our study reveals that the composition of the EPS matrix can determine the meso-scale physical structure of membrane biofilms and in turn its hydraulic resistance. Biofilms grown under P limiting conditions were characterised by dense and homogeneous physical structures with high concentrations of polysaccharides and eDNA. Biofilm grown under nutrient enriched or N limiting conditions were characterised by heterogeneous physical structures with lower concentrations of polysaccharides and eDNA. For P limiting biofilms, 2D-confocal Raman microscopy revealed a homogeneous spatial distribution of anionic functional groups in homogeneous biofilm structures with higher polysaccharide and eDNA concentrations. This study links EPS composition, physical structure and hydraulic resistance of membrane biofilms, with practical relevance for the hydraulic performances of GDM ultrafiltration. Copyright © 2018 Elsevier Ltd. All rights reserved.
Tang, Yinghong; Zheng, Mengkai; Chen, Yu-Lin; Chen, Jianzhen; He, Yu
2017-06-01
Ephedra alkaloids, including ephedrine (EP), pseudoephedrine (PEP) and methylephedrine (MEP), are sympathomimetic compounds with known toxicities but many Ephedra (Ephedrae herba) preparations, such as Ephedra decoction, have been clinically applied for centuries. In order to explore the possible detoxification mechanism of Ephedra alkaloids, four representative compounds in Ephedra decoction (cinnamic acid, amygdalin, glycyrrhizic acid and liquiritin) were studied for their pharmacokinetic effects on Ephedra alkaloids in Sprague-Dawley rats. Animals were randomly divided into six groups, with six rats in each. Rats were treated orally with EP-PEP-MEP (20 mg/kg EP + 20 mg/kg PEP + 20 mg/kg MEP) and different combinations of cinnamic acid (3.03 mg/kg), amygdalin (56.97 mg/kg), glycyrrhizic acid (12.42 mg/kg), liquiritin (3.79 mg/kg) with EP-PEP-MEP, and 20 mg/kg EP + 20 mg/kg PEP + 20 mg/kg MEP + 3.03 mg/kg cinnamic acid + 56.97 mg/kg amygdalin + 12.42 mg/kg glycyrrhizic acid + 3.79 mg/kg liquiritin. Blood samples (0.5 mL) were taken from the orbital sinus venous plexus into heparinized tubes at 5, 10, 20, 30, 45, 60, 90, 120, 180, 240, 300 and 360 min (6 rats per time point in each group) following single administration. The concentrations of Ephedra alkaloids in rat plasma were determined using a validated high performance liquid chromatography method. Area under the concentration-time curve from 0 to 360 min (AUC 0-t ) of EP, PEP and MEP were 666.99, 650.76 and 632.37 µg·min/mL, respectively. Maximum plasma concentration (C max ) of EP, PEP and MEP were 4.15, 4.08 and 3.59 μg/mL, respectively. Mean residence time (MRT) of EP, PEP and MEP were 197.00, 173.97 and 183.87 min, respectively, when the rats were treated with EP-PEP-MEP. Cinnamic acid increased the AUC 0-t of EP while decreased C max of EP, amygdalin and glycyrrhizic acid increased C max and AUC 0-t of EP and PEP, while liquiritin decreased AUC 0-t of EP and PEP. The four representative compounds reduced MRT of EP, PEP and MEP, four compounds decreased AUC 0-t of MEP. The EP-PEP-MEP + cinnamic acid + amygdalin + glycyrrhizic acid + liquiritin group increased AUC 0-t of EP while decreased MRT of EP, increased MRT of PEP while decreased AUC 0-t of PEP. The EP-PEP-MEP + cinnamic acid + amygdalin + glycyrrhizic acid + liquiritin group decreased MRT, AUC 0-t and C max of MEP. Significant changes in pharmacokinetic parameters of EP, PEP and MEP were observed after oral administration with different combinations. The pharmacokinetic results reported here might provide reference for clinical usage of Ephedra alkaloids.
1.5D quasilinear model and its application on beams interacting with Alfvén eigenmodes in DIII-D
NASA Astrophysics Data System (ADS)
Ghantous, K.; Gorelenkov, N. N.; Berk, H. L.; Heidbrink, W. W.; Van Zeeland, M. A.
2012-09-01
We propose a model, denoted here by 1.5D, to study energetic particle (EP) interaction with toroidal Alfvenic eigenmodes (TAE) in the case where the local EP drive for TAE exceeds the stability limit. Based on quasilinear theory, the proposed 1.5D model assumes that the particles diffuse in phase space, flattening the pressure profile until its gradient reaches a critical value where the modes stabilize. Using local theories and NOVA-K simulations of TAE damping and growth rates, the 1.5D model calculates the critical gradient and reconstructs the relaxed EP pressure profile. Local theory is improved from previous study by including more sophisticated damping and drive mechanisms such as the numerical computation of the effect of the EP finite orbit width on the growth rate. The 1.5D model is applied on the well-diagnosed DIII-D discharges #142111 [M. A. Van Zeeland et al., Phys. Plasmas 18, 135001 (2011)] and #127112 [W. W. Heidbrink et al., Nucl. Fusion. 48, 084001 (2008)]. We achieved a very satisfactory agreement with the experimental results on the EP pressure profiles redistribution and measured losses. This agreement of the 1.5D model with experimental results allows the use of this code as a guide for ITER plasma operation where it is desired to have no more than 5% loss of fusion alpha particles as limited by the design.
Xie, Shaobing; Zhang, Yanni; Xu, Zhenhang; Zhang, Jianhui; Wu, Xuewen; Sun, Hong
2017-06-28
To compare the effect of endoscopic-assisted low temperature plasma (ELTP) and electric planer (EP) on the treatment of adenoid hypertrophy. Methods: We searched China National Knowledge Infrastructure (CNKI), Wanfang Database, Weipu Database, Chinese Biomedical Literature (CMB), PubMed, Embase, Cochrane Database, and collected the randomized controlled studies regarding the effect of ELTP and EP on the treatment of adenoid hypertrophy from January 2007 to June 2016. Methodologies were used to evaluate the included studies, and Meta-analysis was performed by Revman 5.2. Results: Thirteen studies including 1 448 patients fulfilled the study requirement. Seven hundred and twenty-two patients were treated with ELTP, and 726 patients were treated with EP. The Meta-analysis showed: compared with EP, ELTP could improve the cure rare (OR=3.19, 95% CI 1.42 to 7.15, P=0.005), reduce the blood loss during surgery (MD=-20.35, 95% CI -20.84 to -19.87, P<0.001), shorten the operation time (MD=-15.71, 95% CI -18.06 to -12.17, P<0.001), and reduce the incidence of complications (OR=0.13, 95% CI 0.06 to 0.30, P<0.001), while there was no difference between the 2 groups in the postoperative residual rate of adenoid, postoperative hemorrhage rate and the rate of torus tubarius injury. Conclusion: Comparing with EP, ELTP shows more advantages in the adenoidectomy.
Nutrient depletion in Bacillus subtilis biofilms triggers matrix production
NASA Astrophysics Data System (ADS)
Zhang, Wenbo; Seminara, Agnese; Suaris, Melanie; Brenner, Michael P.; Weitz, David A.; Angelini, Thomas E.
2014-01-01
Many types of bacteria form colonies that grow into physically robust and strongly adhesive aggregates known as biofilms. A distinguishing characteristic of bacterial biofilms is an extracellular polymeric substance (EPS) matrix that encases the cells and provides physical integrity to the colony. The EPS matrix consists of a large amount of polysaccharide, as well as protein filaments, DNA and degraded cellular materials. The genetic pathways that control the transformation of a colony into a biofilm have been widely studied, and yield a spatiotemporal heterogeneity in EPS production. Spatial gradients in metabolites parallel this heterogeneity in EPS, but nutrient concentration as an underlying physiological initiator of EPS production has not been explored. Here, we study the role of nutrient depletion in EPS production in Bacillus subtilis biofilms. By monitoring simultaneously biofilm size and matrix production, we find that EPS production increases at a critical colony thickness that depends on the initial amount of carbon sources in the medium. Through studies of individual cells in liquid culture we find that EPS production can be triggered at the single-cell level by reducing nutrient concentration. To connect the single-cell assays with conditions in the biofilm, we calculate carbon concentration with a model for the reaction and diffusion of nutrients in the biofilm. This model predicts the relationship between the initial concentration of carbon and the thickness of the colony at the point of internal nutrient deprivation.
Long acting systemic HIV pre-exposure prophylaxis: an examination of the field.
Lykins, William R; Luecke, Ellen; Johengen, Daniel; van der Straten, Ariane; Desai, Tejal A
2017-12-01
Oral pre-exposure prophylaxis for the prevention of HIV-1 transmission (HIV PrEP) has been widely successful as demonstrated by a number of clinical trials. However, studies have also demonstrated the need for patients to tightly adhere to oral dosing regimens in order to maintain protective plasma and tissue concentrations. This is especially true for women, who experience less forgiveness from dose skipping than men in clinical trials of HIV PrEP. There is increasing interest in long-acting (LA), user-independent forms of HIV PrEP that could overcome this adherence challenge. These technologies have taken multiple forms including LA injectables and implantables. Phase III efficacy trials are ongoing for a LA injectable candidate for HIV PrEP. This review will focus on the design considerations for both LA injectable and implantable platforms for HIV PrEP. Additionally, we have summarized the existing LA technologies currently in clinical and pre-clinical studies for HIV PrEP as well as other technologies that have been applied to HIV PrEP and contraceptives. Our discussion will focus on the potential application of these technologies in low resource areas, and their use in global women's health.
The Set of Diagnostics for the First Operation Campaign of the Wendelstein 7-X Stellarator
NASA Astrophysics Data System (ADS)
König, Ralf; Baldzuhn, J.; Biel, W.; Biedermann, C.; Bosch, H. S.; Bozhenkov, S.; Bräuer, T.; Brotas de Carvalho, B.; Burhenn, R.; Buttenschön, B.; Cseh, G.; Czarnecka, A.; Endler, M.; Erckmann, V.; Estrada, T.; Geiger, J.; Grulke, O.; Hartmann, D.; Hathiramani, D.; Hirsch, M.; Jabłonski, S.; Jakubowski, M.; Kaczmarczyk, J.; Klinger, T.; Klose, S.; Kocsis, G.; Kornejew, P.; Krämer-Flecken, A.; Kremeyer, T.; Krychowiak, M.; Kubkowska, M.; Langenberg, A.; Laqua, H. P.; Laux, M.; Liang, Y.; Lorenz, A.; Marchuk, A. O.; Moncada, V.; Neubauer, O.; Neuner, U.; Oosterbeek, J. W.; Otte, M.; Pablant, N.; Pasch, E.; Pedersen, T. S.; Rahbarnia, K.; Ryc, L.; Schmitz, O.; Schneider, W.; Schuhmacher, H.; Schweer, B.; Stange, T.; Thomsen, H.; Travere, J.-M.; Szepesi, T.; Wenzel, U.; Werner, A.; Wiegel, B.; Windisch, T.; Wolf, R.; Wurden, G. A.; Zhang, D.; Zimbal, A.; Zoletnik, S.; the W7-X Team
2015-10-01
Wendelstein 7-X (W7-X) is a large optimized stellarator (B=2.5T, V=30m3) aiming at demonstrating the reactor relevance of the optimized stellarators. In 2015 W7-X will begin its first operation phase (OP1.1) with five inertially cooled inboard limiters made of graphite. Assuming the heat loads can be spread out evenly between the limiters, 1 second discharges at 2 MW of ECRH heating power could be run in OP1.1. The expected plasma parameters will be sufficient to demonstrate the readiness of the installed diagnostics and even to run a first physics program. The diagnostics available for this first operation phase, including some special limiter diagnostics, and their capabilities are being presented. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics
The USC-OSA-EPS section activities in optics
NASA Astrophysics Data System (ADS)
Aymerich, María.; Cambronero-López, Ferran; Aragón, Ángel L.; Delgado, Tamara; Blanco, Manuel; Gómez Varela, Ana I.; Gargallo, Ana; Williamson, Sandra; Amorín, Adán.; Sánchez-García, Ángel; Bao-Varela, Carmen; Flores-Arias, M. Teresa
2017-08-01
The USC-OSA Student Chapter and USC-EPS Young Minds Section is a group financed by The Optical Society (OSA) and the European Physical Society (EPS). It is formed by PhD and degree students from the Universidade de Santiago de Compostela (USC) and one supervisor of the Faculty of Physics. Its main goal is to promote and diffuse Optics in the society. For this purpose, the group carries out several activities in the academic and non-academic community. The group is also committed to the professional development of our members and motivates the exposition of our work into the scientific community.
Koenig, H C; Mounzer, K; Daughtridge, G W; Sloan, C E; Lalley-Chareczko, L; Moorthy, G S; Conyngham, S C; Zuppa, A F; Montaner, L J; Tebas, P
2017-07-01
Tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) is approved for pre-exposure prophylaxis (PrEP) against HIV infection. Adherence is critical for the success of PrEP, but current adherence measurements are inadequate for real-time adherence monitoring. We developed and validated a urine assay to measure tenofovir (TFV) to objectively monitor adherence to PrEP. We developed a urine assay using high-performance liquid chromatography coupled to tandem mass spectrometry with high sensitivity/specificity for TFV that allowed us to determine TFV concentrations in log 10 categories between 0 and 10 000 ng/mL. We validated the assay in three cohorts: (1) HIV-positive subjects with undetectable viral loads on a TDF/FTC-based regimen, (2) healthy HIV-negative subjects who received a single dose of TDF/FTC, and (3) HIV-negative subjects receiving daily TDF/FTC as PrEP for 24 weeks. The urine assay detected TFV with greater sensitivity than plasma-based measures and with a window of measurements within 7 days of the last TDF/FTC dose. Based on the urine log-linear clearance after the last dose and its concordance with all detectable plasma levels, a urine TFV concentration > 1000 ng/mL was identified as highly predictive of the presence of TFV in plasma at > 10 ng/mL. The urine assay was able to distinguish high and low adherence patterns within the last 48 h (> 1000 ng/mL versus 10-1000 ng/mL), as well as nonadherence (< 10 ng/mL) extended over at least 1 week prior to measurement. We provide proof of concept that a semiquantitative urine assay measuring levels of TFV could be further developed into a point-of-care test and be a useful tool to monitor adherence to PrEP. © 2017 British HIV Association.
NASA Astrophysics Data System (ADS)
Qing, XIE; Haofan, LIN; Shuai, ZHANG; Ruixue, WANG; Fei, KONG; Tao, SHAO
2018-02-01
Non-thermal plasma surface modification for epoxy resin (EP) to improve the insulation properties has wide application prospects in gas insulated switchgear and gas insulated transmission line. In this paper, a pulsed Ar dual dielectrics atmospheric-pressure plasma jet (APPJ) was used for SiC x H y O z thin film deposition on EP samples. The film deposition was optimized by varying the treatment time while other parameters were kept at constants (treatment distance: 10 mm, precursor flow rate: 0.6 l min-1, maximum instantaneous power: 3.08 kW and single pulse energy: 0.18 mJ). It was found that the maximum value of flashover voltages for negative and positive voltage were improved by 18% and 13% when the deposition time was 3 min, respectively. The flashover voltage reduced as treatment time increased. Moreover, all the surface conductivity, surface charge dissipation rate and surface trap level distribution reached an optimal value when thin film deposition time was 3 min. Other measurements, such as atomic force microscopy and scanning electron microscope for EP surface morphology, Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy for EP surface compositions, optical emission spectra for APPJ deposition process were carried out to better understand the deposition processes and mechanisms. The results indicated that the original organic groups (C-H, C-C, C=O, C=C) were gradually replaced by the Si containing inorganic groups (Si-O-Si and Si-OH). The reduction of C=O in ester group and C=C in p-substituted benzene of the EP samples might be responsible for shallowing the trap level and then enhancing the flashover voltage. However, when the plasma treatment time was longer than 3 min, the significant increase of the surface roughness might increase the trap level depth and then deteriorate the flashover performance.
40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Certification of limits R MP EP -- Physical and Chemical Characteristics 830.6302 Color R TGAI TGAI -- 830.6303....6319 Miscibility R MP EP 2 830.6320 Corrosion Characteristics R MP EP 3 830.7000 pH R TGAI TGAI -- 830... pesticides are packaged in metal, plastic, or paper containers. 4. Only required for liquid forms of...
NASA Astrophysics Data System (ADS)
Hou, Yawei; Zhu, Ping; Zou, Zhihui; Kim, Charlson C.; Hu, Zhaoqing; Wang, Zhengxiong
2016-10-01
The energetic-particle (EP) driven toroidal Alfvén eigenmodes (TAEs) in a circular-shaped large aspect ratio tokamak are studied using the hybrid kinetic-MHD model in the NIMROD code, where the EPs are advanced using the δf particle-in-cell (PIC) method and their kinetic effects are coupled to the bulk plasma through moment closures. Two initial distributions of EPs, Maxwell and slowing-down, are considered. The influence of EP parameters, including density, temperature and density gradient, on the frequency and the growth rate of TAEs are obtained and benchmarked with theory and gyrokinetic simulations for the Maxwell distribution with good agreement. When the density and temperature of EPs are above certain thresholds, the transition from TAE to energetic particle modes (EPM) occurs and the mode structure also changes. Comparisons between Maxwell and slowing-down distributions in terms of EP-driven TAEs and EPMs will also be presented and discussed. Supported by the National Magnetic Confinement Fusion Science Program of China Grant Nos. 2014GB124002 and 2015GB101004, and the Natural Science Foundation of China Grant No. 11205194.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bass, Eric M.; Waltz, R. E.
Here, a “stiff transport” critical gradient model of energetic particle (EP) transport by EPdriven Alfven eigenmodes (AEs) is verified against local nonlinear gyrokinetic simulations of a well-studied beam-heated DIII-D discharge 146102. A greatly simplifying linear “recipe” for the limiting EP-density gradient (critical gradient) is considered here. In this recipe, the critical gradient occurs when the AE linear growth rate, driven mainly by the EP gradient, exceeds the ion temperature gradient (ITG) or trapped electron mode (TEM) growth rate, driven by the thermal plasma gradient, at the same toroidal mode number (n) as the AE peak growth, well below the ITG/TEMmore » peak n. This linear recipe for the critical gradient is validated against the critical gradient determined from far more expensive local nonlinear simulations in the gyrokinetic code GYRO, as identified by the point of transport runaway when all driving gradients are held fixed. The reduced linear model is extended to include the stabilization from equilibrium E×B velocity shear. The nonlinear verification unambiguously endorses one of two alternative recipes proposed in Ref. 1: the EP-driven AE growth rate should be determined with rather than without added thermal plasma drive.« less
Bass, Eric M.; Waltz, R. E.
2017-12-08
Here, a “stiff transport” critical gradient model of energetic particle (EP) transport by EPdriven Alfven eigenmodes (AEs) is verified against local nonlinear gyrokinetic simulations of a well-studied beam-heated DIII-D discharge 146102. A greatly simplifying linear “recipe” for the limiting EP-density gradient (critical gradient) is considered here. In this recipe, the critical gradient occurs when the AE linear growth rate, driven mainly by the EP gradient, exceeds the ion temperature gradient (ITG) or trapped electron mode (TEM) growth rate, driven by the thermal plasma gradient, at the same toroidal mode number (n) as the AE peak growth, well below the ITG/TEMmore » peak n. This linear recipe for the critical gradient is validated against the critical gradient determined from far more expensive local nonlinear simulations in the gyrokinetic code GYRO, as identified by the point of transport runaway when all driving gradients are held fixed. The reduced linear model is extended to include the stabilization from equilibrium E×B velocity shear. The nonlinear verification unambiguously endorses one of two alternative recipes proposed in Ref. 1: the EP-driven AE growth rate should be determined with rather than without added thermal plasma drive.« less
Chiral modes and directional lasing at exceptional points
Peng, Bo; Özdemir, Şahin Kaya; Liertzer, Matthias; Chen, Weijian; Kramer, Johannes; Yılmaz, Huzeyfe; Wiersig, Jan; Yang, Lan
2016-01-01
Controlling the emission and the flow of light in micro- and nanostructures is crucial for on-chip information processing. Here we show how to impose a strong chirality and a switchable direction of light propagation in an optical system by steering it to an exceptional point (EP)—a degeneracy universally occurring in all open physical systems when two eigenvalues and the corresponding eigenstates coalesce. In our experiments with a fiber-coupled whispering-gallery-mode (WGM) resonator, we dynamically control the chirality of resonator modes and the emission direction of a WGM microlaser in the vicinity of an EP: Away from the EPs, the resonator modes are nonchiral and laser emission is bidirectional. As the system approaches an EP, the modes become chiral and allow unidirectional emission such that by transiting from one EP to another one the direction of emission can be completely reversed. Our results exemplify a very counterintuitive feature of non-Hermitian physics that paves the way to chiral photonics on a chip. PMID:27274059
Assessment of environmental effects on Space Station Freedom Electrical Power System
NASA Technical Reports Server (NTRS)
Lu, Cheng-Yi; Nahra, Henry K.
1991-01-01
Analyses of EPS (electrical power system) interactions with the LEO (low earth orbit) environment are described. The results of these analyses will support EPS design so as to be compatible with the natural and induced environments and to meet power, lifetime, and performance requirements. The environmental impacts to the Space Station Freedom EPS include aerodynamic drag, atomic oxygen erosion, ultraviolet degradation, VXB effect, ionizing radiation dose and single event effects, electromagnetic interference, electrostatic discharge, plasma interactions (ion sputtering, arcing, and leakage current), meteoroid and orbital debris threats, thermal cycling effects, induced current and voltage potential differences in the SSF due to induced electric field, and contamination degradation.
Environmental interactions of the Space Station Freedom electric power system
NASA Technical Reports Server (NTRS)
Nahra, Henry K.; Lu, Cheng-Yi
1991-01-01
The Space Station Freedom operates in a low earth orbit (LEO) environment. Such operation results in different potential interactions with the Space Station systems including the Electric Power System (EPS). These potential interactions result in environmental effects which include neutral species effects such as atomic oxygen erosion, effects of micrometeoroid and orbital debris impacts, plasma effects, ionizing radiation, and induced contamination degradation effects. The EPS design and its interactions with the LEO environment are briefly described and the results of analyses and testing programs planned and performed thus far to resolve environmental concerns related to the EPS and its function in LEO environment.
The Effects Of Physical And Biological Cohesion On Bedforms
NASA Astrophysics Data System (ADS)
Parsons, D. R.; Schindler, R.; Baas, J.; Hope, J. A.; Malarkey, J.; Paterson, D. M.; Peakall, J.; Manning, A. J.; Ye, L.; Aspden, R.; Alan, D.; Bass, S. J.
2014-12-01
Most coastal sediments consist of complex mixtures of cohesionless sands, physically-cohesive clays and extra cellular polymeric substances (EPS) that impart biological cohesion. Yet, our ability to predict bedform dimensions in these substrates is reliant on predictions based exclusively on cohesionless sand. We present findings from the COHBED project - which explicitly examines how bedform dynamics are modified by natural cohesion. Our experimental results show that for ripples, height and length are inversely proportional to initial clay content and bedforms take longer to appear, with no ripples when clay content exceeds 18%. When clay is replaced by EPS the development time and time of first appearance of ripples both increase by two orders of magnitude, with no bedforms above 0.125% EPS. For dunes, height and length are also inversely proportional to initial substrate clay content, resulting in a transition from dunes to ripples normally associated with velocity decreases. Addition of low EPS concentrations into the substrate results in yet smaller bedforms at the same clay contents and at high EPS concentrations, biological cohesion supersedes all electrostatic bonding, and bedform size is no longer related to mud content. The contrast in physical and biological cohesion effects on bedform development result from the disparity between inter-particle electrostatic bonding of clay particles and EPS grain coating and strands that physically link sediments together, which effects winnowing rates as bedforms evolve. These findings have wide ranging implications for bedform predictions in both modern and ancient environments. Coupling of biological and morphological processes not only requires an understanding of how bedform dimensions influence biota and habitat, but also how benthic species can modify bedform dimensions. Consideration of both aspects provides a means in which fluid dynamics, sediment transport and ecosystem energetics can be linked to yield improved predictions of morphological and habitat adjustment.
Shi, Yifan; Rankin, Matthew M; Norquay, Lisa D; Weng, Naidong; Patel, Shefali
2018-05-25
Sulprostone is a potent prostaglandin E 2 (PGE 2 ) analogue and one of the first identified selective G-protein-coupled receptor 3 (EP 3 ) agonists. It has been investigated as a potential antiulcer agent and frequently used in the research of EP 3 antagonist. To assist pharmacokinetic and pharmacodynamic studies, a rapid and sensitive LC-MS/MS method was developed and qualified for the quantitation of sulprostone in monkey plasma. Using electrospray ionization mass spectrometry, an ammonium adduct in positive mode was chosen for analysis which had seven times of the sensitivity of the depronated ion in negative mode. Latanoprost, a prostaglandin F 2α analogue, was used as the internal standard while good sensitivity and chromatography were obtained on a 2.6 μm core-shell column with pentafluorophenyl stationary phase. An assay dynamic range of 2 to 4000 ng/mL was achieved with a sample volume of 25 μL plasma on a Sciex API4000 instrument with simple protein precipitation. Several esterase inhibitors including sodium fluoride (NaF), phenylmethanesulfonyl fluoride (PMSF), diisopropylfluorophosphate (DFP), paraoxon and dichlorvos as well as wet ice conditions were explored for the stabilization of sulprostone in monkey plasma. The developed method was successfully applied for the evaluation of pharmacokinetics of sulprostone after intravenous administration of 0.5 mg/kg to cynomolgus monkey. Copyright © 2018 Elsevier B.V. All rights reserved.
LOW COST, EFFICIENT MICROCHANNEL PLASMA OZONE GENERATOR FOR POINT OF USE WATER TREATMENT - PHASE I
A team of EP Purification and the University of Illinois engineers and chemists is pursuing the commercialization of low-cost microchannel plasma modules capable of efficiently producing ozone for...
NASA Astrophysics Data System (ADS)
2014-03-01
Almost dry but never dull: ASE 2014 EuroPhysicsFun shows physics to Europe Institute of Physics for Africa (IOPfA) South Sudan Report October 2013 Celebrating the centenary of x-ray diffraction The Niels Bohr Institute—an EPS Historical Site Nordic Research Symposium on Science Education (NFSUN) 2014: inquiry-based science education in technology-rich environments Physics World Cup 2013
Camacho-Chab, Juan Carlos; Chan-Bacab, Manuel Jesús; Aguila-Ramírez, Ruth Noemí; Bartolo-Pérez, Pascual; Tabasco-Novelo, Carolina; Gaylarde, Christine; Ortega-Morales, Benjamín Otto
2018-01-01
Cadmium is a major heavy metal found in polluted aquatic environments, mainly derived from industrial production processes. We evaluated the biosorption of solubilized Cd2+ using the extracellular polymeric substances (EPS) produced by Bacillus sp. MC3B-22 and Microbacterium sp. MC3B-10 (Microbactan); these bacteria were originally isolated from intertidal biofilms off the coast of Campeche, Mexico. EPS were incubated with different concentrations of cadmium in ultrapure water. Residual Cd2+ concentrations were determined by Inductive Coupled Plasma-Optic Emission Spectrometry and the maximum sorption capacity (Qmax) was calculated according to the Langmuir model. EPS were characterized by X-ray photoelectron spectroscopy (XPS) before and after sorption. The Qmax of Cd2+ was 97 mg g−1 for Microbactan and 141 mg g−1 for MC3B-22 EPS, these adsorption levels being significantly higher than previously reported for other microbial EPS. In addition, XPS analysis revealed changes in structure of EPS after biosorption and showed that amino functional groups contributed to the binding of Cd2+, unlike other studies that show the carbohydrate fraction is responsible for this activity. This work expands the current view of bacterial species capable of synthesizing EPS with biosorbent potential for cadmium and provides evidence that different chemical moieties, other than carbohydrates, participate in this process. PMID:29439486
Del Cerro, M C R; Ortega, E; Gómez, F; Segovia, S; Pérez-Laso, C
2015-07-01
Environmental prenatal stress (EPS) has effects on fetuses that are long-lasting, altering their hormone levels, brain morphology and behavior when they reach maturity. In previous research, we demonstrated that EPS affects the expression of induced maternal behavior (MB), the neuroendocrine system, and morphology of the sexually dimorphic accessory olfactory bulb (AOB) involved in reproductive behavior patterns. The bed nucleus of the accessory olfactory tract (BAOT) is another vomeronasal (VN) structure that plays an inhibitory role in rats in the expression of induced maternal behavior in female and male virgins. In the present study, we have ascertained whether the behavioral, neuroendocrine, and neuromorphological alterations of the AOB found after EPS also appear in the BAOT. After applying EPS to pregnant rats during the late gestational period, in their female offspring at maturity we tested induced maternal behavior, BAOT morphology and plasma levels of testosterone (T), estradiol (E2), progesterone (P), adrenocorticotropic hormone (ACTH) and corticosterone (Cpd B). EPS: a) affected the induction of MB, showed a male-like pattern of care for pups, b) elevated plasma levels of Cpd B and reduced E2 in comparison with the controls, and c) significantly increased the number of BAOT neurons compared to the control females and comparable to the control male group. These findings provide further evidence that stress applied to pregnant rats produces long-lasting behavioral, endocrine and neuroanatomical alterations in the female offspring that are evident when they become mature. Copyright © 2015 Elsevier Inc. All rights reserved.
Excitation of Alfvén modes by energetic particles in magnetic fusion
NASA Astrophysics Data System (ADS)
Gorelenkov, N. N.
2012-09-01
Ions with energies above the plasma ion temperature (also called super thermal, hot or energetic particles - EP) are utilized in laboratory experiments as a plasma heat source to compensate for energy loss. Sources for super thermal ions are direct injection via neutral beams, RF heating and fusion reactions. Being super thermal, ions have the potential to induce instabilities of a certain class of magnetohydrodynamics (MHD) cavity modes, in particular, various Alfvén and Alfvénacoustic Eigenmodes. It is an area where ideal MHD and kinetic theories can be tested with great accuracy. This paper touches upon key motivations to study the energetic ion interactions with MHD modes. One is the possibility of controlling the heating channel of present and future tokamak reactors via EP transport. In some extreme circumstances, uncontrolled instabilities led to vessel wall damages. This paper reviews some experimental and theoretical advances and the developments of the predictive tools in the area of EP wave interactions. Some recent important results and challenges are discussed. Many predicted instabilities pose a challenge for ITER, where the alpha-particle population is likely to excite various modes.
40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Product Chemistry and Composition 885.1100 Product Identity R MP EP -- 885.1200 Manufacturing process R... Certification of limits R MP EP -- Physical and Chemical Characteristics 830.6302 Color R TGAI TGAI -- 830.6303...
40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Product Chemistry and Composition 885.1100 Product Identity R MP EP -- 885.1200 Manufacturing process R... Certification of limits R MP EP -- Physical and Chemical Characteristics 830.6302 Color R TGAI TGAI -- 830.6303...
Reaction kinetics of a kHz-driven atmospheric pressure plasma with humid air impurities
NASA Astrophysics Data System (ADS)
Murakami, T.; Algwari, Q. Th.; Niemi, K.; Gans, T.; O'Connell, D.; Graham, W. G.
2013-09-01
Atmospheric-pressure plasma jets (APPJs) have been gaining attention because of their great potential in bio-plasma applications. It is important to know the complex chemical kinetics of the reactive multi-species plasma. This is a study starting to address this by using a 0D time-dependent global simulation (comprising 1050 elementary reactions among 59 specie) of kHz-driven (20 kHz) APPJ with a helium-based oxygen-mixture (0.5%) with ambient humid air impurity. The present model is initiated from time dependent measurements and estimates of the basic plasma properties. The dominant neutral reactive species are reactive oxygen species and atomic hydrogen. The positive and negative oxygen ions and electrons are the most pronounced charged species. While most of the neutral reactive species are only weakly modulated at the driving frequency, the atomic oxygen metastables and atomic nitrogen metastables are strongly modulated. So are also the electrons and most of the positive and negative ions, but some are not, as will be discussed. This work was supported by KAKENHI (MEXT 24110704) and (JSPS 24561054),and UK EPSRC through a Career Acceleration Fellowship (EP/H003797/1) and Science and Innovation Award (EP/D06337X/1).
Code of Federal Regulations, 2014 CFR
2014-07-01
... notes Product Chemistry and Composition 885.1100 Product identity R MP EP 885.1200 Manufacturing process....1500 Certification of limits R MP EP Physical and Chemical Characteristics 830.6302 Color R TGAI TGAI...
Code of Federal Regulations, 2013 CFR
2013-07-01
... notes Product Chemistry and Composition 885.1100 Product identity R MP EP 885.1200 Manufacturing process....1500 Certification of limits R MP EP Physical and Chemical Characteristics 830.6302 Color R TGAI TGAI...
ERIC Educational Resources Information Center
Bachman, Nancy J.; Bischoff, Paul J.; Gallagher, Hugh; Labroo, Sunil; Schaumloffel, John C.
2008-01-01
Now in its fourth year, PR[superscript 2]EPS is a National Science Foundation funded initiative designed to recruit high school students to attend college majoring in the physical sciences, including engineering and secondary science education, and to help ensure their retention within the program until graduation. A central feature of the…
Ezendam, Nicole P M; Springer, Andrew E; Brug, Johannes; Oenema, Anke; Hoelscher, Deanna H
2011-01-01
The aim of the study was to compare the change in energy balance-related behaviors from 2000-2002 to 2004-2005 between 2 Texas regions with distinct patterns in obesity prevalence (decrease in the El Paso region [EP] and leveling off in the Rio Grande Valley region [RGV]) and to determine the role of the behaviors in the difference in obesity prevalence between the regions. Cross-sectional measurements of the School Physical Activity and Nutrition Study. Elementary schools. 3,949 children (9-10 years). Body mass index (objectively measured) and behaviors (self-assessed). Probability and post-stratification weighting procedures and mediation analysis. Compared to students in the RGV, students in the EP experienced a smaller decrease in sports team participation, an increase in regular meal consumption, and an increase in the frequency of milk/yogurt, cereal, sweet snacks, and frozen dessert consumption between measurement periods. Prevalence of frequent television viewing was lower in the EP. The lower body mass index in the EP was associated with regular meal consumption, and higher milk/yogurt and sweet snack consumption. Improvement of physical activity, sedentary behaviors, and healthful diet, but not unhealthful diet like sweet snack consumption, seem to be related to the decrease in obesity in the EP. Copyright © 2011 Society for Nutrition Education. Published by Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marhavilas, P. K.; Sarris, E. T.; Anagnostopoulos, G. C.
2011-01-04
The ratio of the plasma pressure to the magnetic field pressure (or of their energy densities) which is known as the plasma parameter 'beta'({beta}) has important implications to the propagation of energetic particles and the interaction of the solar wind with planetary magnetospheres. Although in the scientific literature the contribution of the superthermal particles to the plasma pressure is generally assumed negligible, we deduced, by analyzing energetic particles and magnetic field measurements recorded by the Ulysses spacecraft, that in a series of events, the energy density contained in the superthermal tail of the particle distribution is comparable to or evenmore » higher than the energy density of the magnetic field, creating conditions of high-beta plasma. More explicitly, in this paper we analyze Ulysses/HI-SCALE measurements of the energy density ratio (parameter {beta}{sub ep}) of the energetic ions'(20 keV to {approx}5 MeV) to the magnetic field's in order to find occurrences of high-beta ({beta}{sub ep}>1) superthermal plasma conditions in the environment of the Jovian magnetosphere, which is an interesting plasma laboratory and an important source of emissions in our solar system. In particular, we examine high-beta ion events close to Jupiter's bow shock, which are produced by two processes: (a) bow shock ion acceleration and (b) ion leakage from the magnetosphere.« less
Progress in understanding the enhanced pedestal H-mode in NSTX
Gerhardt, S. P.; Canik, J. M.; Maingi, R.; ...
2014-08-01
The paper describes the enhanced pedestal (EP) H-mode observed in the National Spherical Torus Experiment (NSTX). The defining characteristics of EP H-mode are given, namely i)transition after the L- to H-mode transition, ii) region of very steep ion temperature gradient, and iii) associated region of strong rotational shear. A newly observed long-pulse EP H-mode example shows quiescent behavior for as long as the heating and current drive sources are maintained. Cases are shown where the region of steep ion temperature gradient is located at the very edge, and cases where it is shifted up to 10 cm inward from themore » plasma edge; these cases are united by a common dependence of the ion temperature gradient on the toroidal rotation frequency shear. EP H-mode examples have been observed across a wide range of q95 and pedestal collisionality. No strong changes in the fluctuation amplitudes have been observed following the eP H-mode transition, and transport analysis indicates that the ion t hermal transport is comparable to or less than anticipated from a simple neoclassical transport model. Cases are shown where EP H-modes were reliably generated, through these low-q95 examples were difficult to sustain. A case where an externally triggered ELM precipitates the transition to EP H-mode is also shown, though an initial experiment designed to trigger EP-H-modes in this fashion was successful.« less
Chudziak, Jakub; Burt, Deborah J; Mohan, Sumitra; Rothwell, Dominic G; Mesquita, Bárbara; Antonello, Jenny; Dalby, Suzanne; Ayub, Mahmood; Priest, Lynsey; Carter, Louise; Krebs, Matthew G; Blackhall, Fiona; Dive, Caroline; Brady, Ged
2016-01-21
Circulating tumour cells (CTCs) have potential utility as minimally-invasive biomarkers to aid cancer treatment decision making. However, many current CTC technologies enrich CTCs using specific surface epitopes that do not necessarily reflect CTC heterogeneity. Here we evaluated the epitope-independent Parsortix system which enriches CTCs based on size and rigidity using both healthy normal volunteer blood samples spiked with tumour cells and blood samples from patients with small cell lung cancer (SCLC). Blood samples were maintained unfractionated at room temperature for up to 4 days followed by plasma removal for circulating free DNA (cfDNA) isolation and direct application of the remaining cell component to the Parsortix system. For tumour cells expressing the EpCAM cell surface marker the numbers of spiked cells retained using the Parsortix system and by EpCAM-positive selection using CellSearch® were not significantly different, whereas only the Parsortix system showed strong enrichment of cells with undetectable EpCAM expression. In a pilot clinical study we banked both enriched CTCs as well as plasma from SCLC patient blood samples. Upon retrieval of the banked Parsortix cellular samples we could detect cytokeratin positive CTCs in all 12 SCLC patients tested. Interestingly, processing parallel samples from the same patients by EpCAM enrichment using CellSearch® revealed only 83% (10/12) with cytokeratin positive CTCs indicating the Parsortix system is enriching for EpCAM negative SCLC CTCs. Our combined results indicate the Parsortix system is a valuable tool for combined cfDNA isolation and CTC enrichment that enables CTC analysis to be extended beyond dependence on surface epitopes.
The pseudo-symmetric optimization of the National Compact Stellarator Experiment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Isaev, M.Y.; Mikhailov, M.I.; Monticello, D.A.
1999-08-01
A new experiment, the National Compact Stellarator Experiment (NCSX) [Monticello {ital et al.} {open_quotes}Physics Consideration for the Design of NCSX,{close_quotes} {ital Proceedings of 25th EPS Conference on Controlled Fusion and Plasma Physics, Prague, 1998} (European Physical Society, Petit-Lancy), paper 1.187], hopes to overcome the deleterious ripple transport usually associated with stellarators by creating a quasi-axisymmetric configuration. A quasi-axisymmetric configuration is one in which the Fourier spectrum of the magnetic field strength in so-called Boozer coordinates is dominated by the toroidal angle averaged (n=0) components. In this article the concept of pseudosymmetry is used to improve ripple transport in a four-periodmore » variant of NCSX. By definition, pseudosymmetric magnetic configurations have no locally trapped particles. To obtain a pseudosymmetric configuration, different target functions are considered. It is found that a target function equal to the area of ripple of the magnetic field magnitude along the field line is very effective in reducing the neoclassical transport coefficient. {copyright} {ital 1999 American Institute of Physics.}« less
Effects of Different Heavy-Resistance Exercise Protocols on Plasma Beta-Endorphin Concentrations
1993-01-01
of O-EP and cortisol. forms of high-intensity exercise, which is performed well above the level that produces V02 .. but uses multi- anaerobic ; opioid...utilizing the Borg CR- ing the rest period length (i.e., from I to 3 min; or in- 10 scale designed to accommodate primarily anaerobic creasing the resistance...O-EP in response to though short-term anaerobic exercise to exhaustion has high-intensity exercise remain unknown, it has been sug- been shown to
High-Speed, High-Power Active Control Coils for HBT-EP
NASA Astrophysics Data System (ADS)
Debono, Bryan
2010-11-01
We report the performance of a newly installed high-speed, high-power active control system for the application of non-symmetric magnetic fields and the study of rotating MHD and resistive wall modes in the HBTEP tokamak. The new control system consists of an array of 120 modular control coils and 40 solid-state, high-power amplifiers that can apply non-symmetric control fields that are more than 10 times larger than previous studies in HBT-EP and exceed 5% of the equilibrium poloidal field strength. Measurements of the current and field response of the control system are presented as a function of frequency and control coil geometry, and these demonstrate the effectiveness of the system to interact with both growing RWM instabilities and long-wavelength modes rotating with the plasma. We describe a research plan to study the interaction of both kink and tearing mode fluctuations with applied static and rotating magnetic perturbations while systematically changing the plasma rotation with a biased molybdenum electrode inserted into the edge plasma.
Simulation and Preliminary Design of a Cold Stream Experiment on Omega EP
NASA Astrophysics Data System (ADS)
Coffing, Shane; Angulo, Adrianna; Trantham, Matt; Malamud, Guy; Kuranz, Carolyn; Drake, R. P.
2017-10-01
Galaxies form within dark matter halos, accreting gas that may clump and eventually form stars. Infalling matter gradually increases the density of the halo, and, if cooling is insufficient, rising pressure forms a shock that slows the infalling gas, reducing star formation. However, galaxies with sufficient cooling become prolific star formers. A recent theory suggests that so called ``stream fed galaxies'' are able to acquire steady streams of cold gas via galactic ``filaments'' that penetrate the halo. The cold, dense filament flowing into a hot, less dense environment is potentially Kelvin-Helmholtz unstable. This instability may hinder the ability of the stream to deliver gas deeply enough into the halo. To study this process, we have begun preliminary design of a well-scaled laser experiment on Omega EP. We present here early simulation results and the physics involved. This work is funded by the U.S. Department of Energy, through the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, Grant Number DE-NA0002956, and the National Laser User Facility Program, Grant Number DE-NA0002719, and through the Laboratory for Laser Energetics, University of Rochester by the NNSA/OICF under Cooperative Agreement No. DE-NA0001944.
The search for an endogenous activator.
Gekowski, K. M.; Atkins, E.
1985-01-01
Certain febrile diseases are unaccompanied by infection or apparent hypersensitivity. In myocardial infarction or pulmonary embolism, for example, fever has been attributed to inflammation and/or tissue necrosis. Exogenous (microbial) pyrogens stimulate both human and animal monocytes/macrophages to produce endogenous pyrogen (EP) in vitro. To determine if plasma and cellular endogeneous mediators (EMs) of inflammation induced EP production, human mononuclear cells (M/L) were incubated for 18 hours with varying amounts of EM and the supernates assayed for EP in rabbits. Neutrophils (PMNs), which do not generate EP and yet are a feature of acute inflammation, were tested. Neither viable, phorbol myristic acetate-stimulated PMNs nor sonicated PMNs, red blood cells, or M/L stimulated human monocytes to produce EP. Human C3b and C5a, which mediate phagocytosis and chemotaxis, respectively, were also inactive. Despite its chemoattractant properties, the synthetic peptide FMLP failed to induce EP release. Since Poly I:Poly C (PIC: a synthetic, double-stranded RNA) is a potent pyrogen in rabbits, we investigated PIC, as well as a native, single-stranded RNA (from E. coli) and DNA (from calf thymus). None was active in vitro, and only PIC caused fever when given to rabbits intravenously. In summary, we have been unable to find an endogenous activator of EP from human monocytes to explain fevers associated with inflammation alone. PMID:3875936
Exopolysaccharides enriched in rare sugars: bacterial sources, production, and applications.
Roca, Christophe; Alves, Vitor D; Freitas, Filomena; Reis, Maria A M
2015-01-01
Microbial extracellular polysaccharides (EPS), produced by a wide range of bacteria, are high molecular weight biopolymers, presenting an extreme diversity in terms of chemical structure and composition. They may be used in many applications, depending on their chemical and physical properties. A rather unexplored aspect is the presence of rare sugars in the composition of some EPS. Rare sugars, such as rhamnose or fucose, may provide EPS with additional biological properties compared to those composed of more common sugar monomers. This review gives a brief overview of these specific EPS and their producing bacteria. Cultivation conditions are summarized, demonstrating their impact on the EPS composition, together with downstream processing. Finally, their use in different areas, including cosmetics, food products, pharmaceuticals, and biomedical applications, are discussed.
Final Technical Report for the Center for Momentum Transport and Flow Organization (CMTFO)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Forest, Cary B.; Tynan, George R.
The Center for Momentum Transport and Flow Organization (CMTFO) is a DOE Plasma Science Center formed in late 2009 to focus on the general principles underlying momentum transport in magnetic fusion and astrophysical systems. It is composed of funded researchers from UCSD, UW Madison, U. Colorado, PPPL. As of 2011, UCSD supported postdocs are collaborating at MIT/Columbia and UC Santa Cruz and beginning in 2012, will also be based at PPPL. In the initial startup period, the Center supported the construction of two basic experiments at PPPL and UW Madison to focus on accretion disk hydrodynamic instabilities and solar physicsmore » issues. We now have computational efforts underway focused on understanding recent experimental tests of dynamos, solar tacholine physics, intrinsic rotation in tokamak plasmas and L-H transition physics in tokamak devices. In addition, we have the basic experiments discussed above complemented by work on a basic linear plasma device at UCSD and a collaboration at the LAPD located at UCLA. We are also performing experiments on intrinsic rotation and L-H transition physics in the DIII-D, NSTX, C-Mod, HBT EP, HL-2A, and EAST tokamaks in the US and China, and expect to begin collaborations on K-STAR in the coming year. Center funds provide support to over 10 postdocs and graduate students each year, who work with 8 senior faculty and researchers at their respective institutions. The Center has sponsored a mini-conference at the APS DPP 2010 meeting, and co-sponsored the recent Festival de Theorie (2011) with the CEA in Cadarache, and will co-sponsor a Winter School in January 2012 in collaboration with the CMSO-UW Madison. Center researchers have published over 50 papers in the peer reviewed literature, and given over 10 talks at major international meetings. In addition, the Center co-PI, Professor Patrick Diamond, shared the 2011 Alfven Prize at the EPS meeting. Key scientific results from this startup period include initial simulations of the effects of boundary conditions on turbulent dynamo experiments; simulations of intrinsic rotation showing the strong link between toroidal rotation and temperature gradients and elucidation of the turbulence symmetry breaking mechanisms that lead to this macroscopic behavior; first experiments in a large tokamak testing the roll of turbulent momentum transport in driving intrinsic rotation; experiments in tokamaks showing strong evidence that zonal flows, together with the more widely recognized mean sheared ExB flow, act to trigger the L-H transition in tokamak devices and the first experimental measurement of collisional viscosity in an unmagnetized plasma. In the coming three year period, we will continue these efforts by a combination of basic hydrodynamic, liquid metal and plasma experiments combined with experiments on numerous tokamak devices around the world. In addition, we will use MHD, gyrofluid and gyrokinetic codes combined with theory to address the problems of interest to the Center.« less
Center for Momentum Transport and Flow Organization (CMTFO). Final technical report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tynan, George R.; Diamond, P. H.; Ji, H.
The Center for Momentum Transport and Flow Organization (CMTFO) is a DOE Plasma Science Center formed in late 2009 to focus on the general principles underlying momentum transport in magnetic fusion and astrophysical systems. It is composed of funded researchers from UCSD, UW Madison, U. Colorado, PPPL. As of 2011, UCSD supported postdocs are collaborating at MIT/Columbia and UC Santa Cruz and beginning in 2012, will also be based at PPPL. In the initial startup period, the Center supported the construction of two basic experiments at PPPL and UW Madison to focus on accretion disk hydrodynamic instabilities and solar physicsmore » issues. We now have computational efforts underway focused on understanding recent experimental tests of dynamos, solar tachocline physics, intrinsic rotation in tokamak plasmas and L-H transition physics in tokamak devices. In addition, we have the basic experiments discussed above complemented by work on a basic linear plasma device at UCSD and a collaboration at the LAPD located at UCLA. We are also performing experiments on intrinsic rotation and L-H transition physics in the DIII-D, NSTX, C-Mod, HBT EP, HL-2A, and EAST tokamaks in the US and China, and expect to begin collaborations on K-STAR in the coming year. Center funds provide support to over 10 postdocs and graduate students each year, who work with 8 senior faculty and researchers at their respective institutions. The Center has sponsored a mini-conference at the APS DPP 2010 meeting, and co-sponsored the recent Festival de Theorie (2011) with the CEA in Cadarache, and will co-sponsor a Winter School in January 2012 in collaboration with the CMSO-UW Madison. Center researchers have published over 50 papers in the peer reviewed literature, and given over 10 talks at major international meetings. In addition, the Center co-PI, Professor Patrick Diamond, shared the 2011 Alfven Prize at the EPS meeting. Key scientific results from this startup period include initial simulations of the effects of boundary conditions on turbulent dynamo experiments; simulations of intrinsic rotation showing the strong link between toroidal rotation and temperature gradients and elucidation of the turbulence symmetry breaking mechanisms that lead to this macroscopic behavior; first experiments in a large tokamak testing the roll of turbulent momentum transport in driving intrinsic rotation; experiments in tokamaks showing strong evidence that zonal flows, together with the more widely recognized mean sheared ExB flow, act to trigger the L-H transition in tokamak devices and the first experimental measurement of collisional viscosity in an unmagnetized plasma. In the coming three year period, we will continue these efforts by a combination of basic hydrodynamic, liquid metal and plasma experiments combined with experiments on numerous tokamak devices around the world. In addition, we will use MHD, gyrofluid and gyrokinetic codes combined with theory to address the problems of interest to the Center.« less
2016-04-14
Swanson AEDC Path 1: Magnetized electron transport impeded across magnetic field lines; transport via electron-particle collisions Path 2*: Electron...T&E (higher pressure, metallic walls) → Impacts stability, performance, plume properties, thruster lifetime Magnetic Field Lines Plasma Plume...Development of T&E Methodologies • Current-Voltage- Magnetic Field (I-V-B) Mapping • Facility Interaction Studies • Background Pressure • Plasma Wall
NASA Astrophysics Data System (ADS)
Carmona, A. M.; Poveda, G.; Sivapalan, M.; Vallejo-Bernal, S. M.; Bustamante, E.
2015-10-01
This paper studies a 3-D generalization of Budyko's framework designed to capture the mutual interdependence among long-term mean actual evapotranspiration (E), potential evapotranspiration (Ep) and precipitation (P). For this purpose we use three dimensionless and dependent quantities: Ψ = E/P, Φ = Ep/P and Ω = E/Ep. This 3-D space and its 2-D projections provide an interesting setting to test the physical soundness of Budyko's hypothesis. We demonstrate analytically that Budyko-type equations are unable to capture the physical limit of the relation between Ω and Φ in humid environments, owing to the unfeasibility of Ep/P → 0 at E/Ep = 1. Using data from 146 sub-catchments in the Amazon River basin we overcome this inconsistency by proposing a physically consistent power law: Ψ = k Φe, with k = 0.66, and e = 0.83 (R2 = 0.93). This power law is compared with two other Budyko-type equations. Taking into account the goodness of fits and the ability to comply with the physical limits of the 3-D space, our results show that the power law is better suited to model the coupled water and energy balances within the Amazon River basin. Moreover, k is found to be related to the partitioning of energy via evapotranspiration in terms of Ω. This suggests that our power law implicitly incorporates the complementary relationship of evapotranspiration into the Budyko curve, which is a consequence of the dependent nature of the studied variables within our 3-D space. This scaling approach is also consistent with the asymmetrical nature of the complementary relationship of evapotranspiration. Looking for a physical explanation for the parameters k and e, the inter-annual variability of individual catchments is studied. Evidence of space-time symmetry in Amazonia emerges, since both between-catchment and between-year variability follow the same Budyko curves. Finally, signs of co-evolution of catchments are explored by linking spatial patterns of the power law parameters with fundamental characteristics of the Amazon River basin. In general, k and e are found to be related to vegetation, topography and water in soils.
Wu, D; Zheng, C Y; Qiao, B; Zhou, C T; Yan, X Q; Yu, M Y; He, X T
2014-08-01
It is shown that the transverse Rayleigh-Taylor-like (RT) instability in the hole-boring radiation pressure acceleration can be suppressed by using an elliptically polarized (EP) laser. A moderate J×B heating of the EP laser will thermalize the local electrons, which leads to the transverse diffusion of ions, suppressing the short wavelength perturbations of RT instability. A proper condition of polarization ratio is obtained analytically for the given laser intensity and plasma density. The idea is confirmed by two-dimensional particle-in-cell simulations, showing that the ion beam driven by the EP laser is more concentrated and intense compared with that of the circularly polarized laser.
2014-01-01
Perovskite oxide manganites with a general formula of R1-x AxMnO3 (where R is a trivalent rare-earth element such as La, Pr, Sm, and A is a divalent alkaline-earth element such as Ca, Sr, and Ba) have received much attention due to their unusual electron-transport and magnetic properties, which are indispensable for applications in microelectronic, magnetic, and spintronic devices. Recent advances in the science and technology have resulted in the feature sizes of microelectronic devices based on perovskite manganite oxides down-scaling into nanoscale dimensions. At the nanoscale, low-dimensional perovskite manganite oxide nanostructures display novel physical properties that are different from their bulk and film counterparts. Recently, there is strong experimental evidence to indicate that the low-dimensional perovskite manganite oxide nanostructures are electronically inhomogeneous, consisting of different spatial regions with different electronic orders, a phenomenon that is named as electronic phase separation (EPS). As the geometry sizes of the low-dimensional manganite nanostructures are reduced to the characteristic EPS length scale (typically several tens of nanometers in manganites), the EPS is expected to be strongly modulated, leading to quite dramatic changes in functionality and more emergent phenomena. Therefore, reduced dimensionality opens a door to the new functionalities in perovskite manganite oxides and offers a way to gain new insight into the nature of EPS. During the past few years, much progress has been made in understanding the physical nature of the EPS in low-dimensional perovskite manganite nanostructures both from experimentalists and theorists, which have a profound impact on the oxide nanoelectronics. This nanoreview covers the research progresses of the EPS in low-dimensional perovskite manganite nanostructures such as nanoparticles, nanowires/nanotubes, and nanostructured films and/or patterns. The possible physical origins of the EPS are also discussed from the signatures of electronic inhomogeneities as well as some theoretical scenarios, to shed light on understanding this phenomenon. Finally, the perspectives to the future researches in this area are also outlined. PMID:25024686
Plasma-grafting polymerization on carbon fibers and its effect on their composite properties
NASA Astrophysics Data System (ADS)
Zhang, Huanxia; Li, Wei
2015-11-01
Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid-base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as Csbnd O, Cdbnd O, and Osbnd Cdbnd O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the plasma-grafting treatments.
Alfvén eigenmode evolution computed with the VENUS and KINX codes for the ITER baseline scenario
DOE Office of Scientific and Technical Information (OSTI.GOV)
Isaev, M. Yu., E-mail: isaev-my@nrcki.ru; Medvedev, S. Yu.; Cooper, W. A.
A new application of the VENUS code is described, which computes alpha particle orbits in the perturbed electromagnetic fields and its resonant interaction with the toroidal Alfvén eigenmodes (TAEs) for the ITER device. The ITER baseline scenario with Q = 10 and the plasma toroidal current of 15 MA is considered as the most important and relevant for the International Tokamak Physics Activity group on energetic particles (ITPA-EP). For this scenario, typical unstable TAE-modes with the toroidal index n = 20 have been predicted that are localized in the plasma core near the surface with safety factor q = 1.more » The spatial structure of ballooning and antiballooning modes has been computed with the ideal MHD code KINX. The linear growth rates and the saturation levels taking into account the damping effects and the different mode frequencies have been calculated with the VENUS code for both ballooning and antiballooning TAE-modes.« less
Evidence cross-validation and Bayesian inference of MAST plasma equilibria
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nessi, G. T. von; Hole, M. J.; Svensson, J.
2012-01-15
In this paper, current profiles for plasma discharges on the mega-ampere spherical tokamak are directly calculated from pickup coil, flux loop, and motional-Stark effect observations via methods based in the statistical theory of Bayesian analysis. By representing toroidal plasma current as a series of axisymmetric current beams with rectangular cross-section and inferring the current for each one of these beams, flux-surface geometry and q-profiles are subsequently calculated by elementary application of Biot-Savart's law. The use of this plasma model in the context of Bayesian analysis was pioneered by Svensson and Werner on the joint-European tokamak [Svensson and Werner,Plasma Phys. Controlledmore » Fusion 50(8), 085002 (2008)]. In this framework, linear forward models are used to generate diagnostic predictions, and the probability distribution for the currents in the collection of plasma beams was subsequently calculated directly via application of Bayes' formula. In this work, we introduce a new diagnostic technique to identify and remove outlier observations associated with diagnostics falling out of calibration or suffering from an unidentified malfunction. These modifications enable a good agreement between Bayesian inference of the last-closed flux-surface with other corroborating data, such as that from force balance considerations using EFIT++[Appel et al., ''A unified approach to equilibrium reconstruction'' Proceedings of the 33rd EPS Conference on Plasma Physics (Rome, Italy, 2006)]. In addition, this analysis also yields errors on the plasma current profile and flux-surface geometry as well as directly predicting the Shafranov shift of the plasma core.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sovinec, Carl
The objective of the Plasma Science and Innovation Center (PSI-Center) is to develop and deploy computational models that simulate conditions in smaller, concept-exploration plasma experiments. The PSIC group at the University of Wisconsin-Madison, led by Prof. Carl Sovinec, uses and enhances the Non-Ideal Magnetohydrodynamics with Rotation, Open Discussion (NIMROD) code, to simulate macroscopic plasma dynamics in a number of magnetic confinement configurations. These numerical simulations provide information on how magnetic fields and plasma flows evolve over all three spatial dimensions, which supplements the limited access of diagnostics in plasma experiments. The information gained from simulation helps explain how plasma evolves.more » It is also used to engineer more effective plasma confinement systems, reducing the need for building many experiments to cover the physical parameter space. The ultimate benefit is a more cost-effective approach to the development of fusion energy for peaceful power production. The supplemental funds provided by the American Recovery and Reinvestment Act of 2009 were used to purchase computer components that were assembled into a 48-core system with 256 Gb of shared memory. The system was engineered and constructed by the group's system administrator at the time, Anthony Hammond. It was successfully used by then graduate student, Dr. John O'Bryan, for computing magnetic relaxation dynamics that occur during experimental tests of non-inductive startup in the Pegasus Toroidal Experiment (pegasus.ep.wisc.edu). Dr. O'Bryan's simulations provided the first detailed explanation of how the driven helical filament of electrical current evolves into a toroidal tokamak-like plasma configuration.« less
Vallerie, Sara N; Kramer, Farah; Barnhart, Shelley; Kanter, Jenny E; Breyer, Richard M; Andreasson, Katrin I; Bornfeldt, Karin E
2016-01-01
Type 1 diabetes mellitus (T1DM) is associated with cardiovascular complications induced by atherosclerosis. Prostaglandin E2 (PGE2) is often raised in states of inflammation, including diabetes, and regulates inflammatory processes. In myeloid cells, a key cell type in atherosclerosis, PGE2 acts predominately through its Prostaglandin E Receptor 4 (EP4; Ptger4) to modulate inflammation. The effect of PGE2-mediated EP4 signaling specifically in myeloid cells on atherosclerosis in the presence and absence of diabetes is unknown. Because diabetes promotes atherosclerosis through increased arterial myeloid cell accumulation, we generated a myeloid cell-targeted EP4-deficient mouse model (EP4M-/-) of T1DM-accelerated atherogenesis to investigate the relationship between myeloid cell EP4, inflammatory phenotypes of myeloid cells, and atherogenesis. Diabetic mice exhibited elevated plasma PGE metabolite levels and elevated Ptger4 mRNA in macrophages, as compared with non-diabetic littermates. PGE2 increased Il6, Il1b, Il23 and Ccr7 mRNA while reducing Tnfa mRNA through EP4 in isolated myeloid cells. Consistently, the stimulatory effect of diabetes on peritoneal macrophage Il6 was mediated by PGE2-EP4, while PGE2-EP4 suppressed the effect of diabetes on Tnfa in these cells. In addition, diabetes exerted effects independent of myeloid cell EP4, including a reduction in macrophage Ccr7 levels and increased early atherogenesis characterized by relative lesional macrophage accumulation. These studies suggest that this mouse model of T1DM is associated with increased myeloid cell PGE2-EP4 signaling, which is required for the stimulatory effect of diabetes on IL-6, markedly blunts the effect of diabetes on TNF-α and does not modulate diabetes-accelerated atherogenesis.
Vallerie, Sara N.; Kramer, Farah; Barnhart, Shelley; Kanter, Jenny E.; Breyer, Richard M.; Andreasson, Katrin I.; Bornfeldt, Karin E.
2016-01-01
Type 1 diabetes mellitus (T1DM) is associated with cardiovascular complications induced by atherosclerosis. Prostaglandin E2 (PGE2) is often raised in states of inflammation, including diabetes, and regulates inflammatory processes. In myeloid cells, a key cell type in atherosclerosis, PGE2 acts predominately through its Prostaglandin E Receptor 4 (EP4; Ptger4) to modulate inflammation. The effect of PGE2-mediated EP4 signaling specifically in myeloid cells on atherosclerosis in the presence and absence of diabetes is unknown. Because diabetes promotes atherosclerosis through increased arterial myeloid cell accumulation, we generated a myeloid cell-targeted EP4-deficient mouse model (EP4M-/-) of T1DM-accelerated atherogenesis to investigate the relationship between myeloid cell EP4, inflammatory phenotypes of myeloid cells, and atherogenesis. Diabetic mice exhibited elevated plasma PGE metabolite levels and elevated Ptger4 mRNA in macrophages, as compared with non-diabetic littermates. PGE2 increased Il6, Il1b, Il23 and Ccr7 mRNA while reducing Tnfa mRNA through EP4 in isolated myeloid cells. Consistently, the stimulatory effect of diabetes on peritoneal macrophage Il6 was mediated by PGE2-EP4, while PGE2-EP4 suppressed the effect of diabetes on Tnfa in these cells. In addition, diabetes exerted effects independent of myeloid cell EP4, including a reduction in macrophage Ccr7 levels and increased early atherogenesis characterized by relative lesional macrophage accumulation. These studies suggest that this mouse model of T1DM is associated with increased myeloid cell PGE2-EP4 signaling, which is required for the stimulatory effect of diabetes on IL-6, markedly blunts the effect of diabetes on TNF-α and does not modulate diabetes-accelerated atherogenesis. PMID:27351842
EPS cautions against budget cuts
NASA Astrophysics Data System (ADS)
Stafford, Ned
2015-03-01
The European Physical Society (EPS) has hit out at plans to remove €2.7bn from the €80bn budget of Horizon 2020 - the European Union's main research funding programme - and use the money instead to help finance a new European Union economic-stimulus initiative.
Cunha, A T M; Carvalho, J O; Kussano, N R; Martins, C F; Mourão, G B; Dode, M A N
2016-12-01
In this study we examined quality, longevity and ability of epididymal sperm (EP) to bind to oviduct explants (OE) after cooling and cryopreservation. Ejaculated (EJ) and EP sperm from seven bulls were evaluated before, during and after cryopreservation for total (TM), progressive motility (PM), sperm morphology, plasma membrane integrity (PMI) and acrosome integrity (ACI). For longevity, cryopreserved EP, EJ and a third group of cells in which EP spermatozoa were incubated with seminal plasm (SP) for 10 min after thawing (EPP group), were compared, and the groups were analyzed at 0, 3, 6, and 24 h for all parameters. Sperm from each group were co-incubated with OE for 30 min, 6 h, and 24 h for binding evaluation. Data were analyzed by the generalized linear models SAS 9.1 (P < 0.05). After cooling, EP displayed higher TM, higher PMI, and higher ACI (P < 0.05) than EJ. No differences were noted in the percentage of spermatozoa with PMI and AI between EJ and EP for fresh, cooled or cryopreserved sperm. However, a reduction in motility occurred in the EJ sperm after cooling, while in EP group such reduction occurred only after cryopreservation. At 6 h of incubation EP and EPP had higher PMI and ACI than EJ (P < 0.05). The number of spermatozoa bound to OE was similar P > 0.05) for all groups either at 30 min or 24 h. We conclude that EP are more resistant to cooling than EJ, and can bind to OE similarly to EJ. Copyright © 2016 Elsevier Inc. All rights reserved.
Extreme ultraviolet diagnostic upgrades for kink mode control on the HBT-EP tokamak
NASA Astrophysics Data System (ADS)
Levesque, J. P.; Brooks, J. W.; Desanto, S.; Mauel, M. E.; Navratil, G. A.; Page, J. W.; Hansen, C. J.; Delgado-Aparicio, L.
2016-10-01
Optical diagnostics can provide non-invasive measurements of tokamak equilibria and the internal characteristics of MHD mode activity. We present research plans and ongoing progress on upgrading extreme ultraviolet (EUV) diagnostics in the HBT-EP tokamak. Four sets of 16 poloidal views will allow tomographic reconstruction of plasma emissivity and internal kink mode structure. Emission characteristics of naturally-occurring m/n = 2/1, 3/2, and 3/1 tearing and kink modes will be compared with expectations from a synthetic diagnostic. Coupling between internal and external modes leading up to disruptions is studied. The internal plasma response to external magnetic perturbations is investigated, and compared with magnetic response measurements. Correlation between internal emissivity and external magnetic measurements provides a global picture of long-wavelength MHD instabilities. Measurements are input to HBT-EP's GPU-based feedback system, allowing active feedback for kink modes using only optical sensors and both magnetic and edge current actuators. A separate two-color, 16-chord tangential system will be installed next year to allow reconstruction of temperature profiles and their fluctuations versus time. Supported by U.S. DOE Grant DE-FG02-86ER53222.
Ponnuru, Venkata Suresh; Challa, B R; Nadendla, Ramarao
2011-11-01
Authors developed a simple, sensitive, selective, rapid, rugged, and reproducible liquid chromatography-tandem mass spectrometry method for the quantification of eletriptan (EP) in human plasma using naratriptan (NP) as an internal standard (IS). Chromatographic separation was performed on Ascentis Express C18, 50 × 4.6 mm, 2.7 μm column. Mobile phase was composed of 0.1% formic acid: methanol (40:60 v/v), with 0.5 mL/min flow rate. Drug and IS were extracted by liquid-liquid extraction. EP and NP were detected with proton adducts at m/z 383.2→84.3 and 336.2→97.8 in multiple reaction monitoring (MRM) positive mode, respectively. The method was validated with the correlation coefficients of (r(2)) ≥ 0.9963 over a linear concentration range of 0.5-250.0 ng/mL. This method demonstrated intra- and inter-day precision within 1.4-9.2% and 4.4-5.5% and accuracy within 96.8-103% and 98.5-99.8% for EP. This method is successfully applied in the bioequivalence study of 24 human volunteers.
Batista Napotnik, Tina; Reberšek, Matej; Vernier, P Thomas; Mali, Barbara; Miklavčič, Damijan
2016-08-01
For this systematic review, 203 published reports on effects of electroporation using nanosecond high-voltage electric pulses (nsEP) on eukaryotic cells (human, animal, plant) in vitro were analyzed. A field synopsis summarizes current published data in the field with respect to publication year, cell types, exposure configuration, and pulse duration. Published data were analyzed for effects observed in eight main target areas (plasma membrane, intracellular, apoptosis, calcium level and distribution, survival, nucleus, mitochondria, stress) and an additional 107 detailed outcomes. We statistically analyzed effects of nsEP with respect to three pulse duration groups: A: 1-10ns, B: 11-100ns and C: 101-999ns. The analysis confirmed that the plasma membrane is more affected with longer pulses than with short pulses, seen best in uptake of dye molecules after applying single pulses. Additionally, we have reviewed measurements of nsEP and evaluations of the electric fields to which cells were exposed in these reports, and we provide recommendations for assessing nanosecond pulsed electric field effects in electroporation studies. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Mode control using two electrodes on HBT-EP
NASA Astrophysics Data System (ADS)
Stewart, I. G.; Brooks, J. W.; Levesque, J. P.; Mauel, M. E.; Navratil, G. A.
2017-10-01
Understanding the effects of plasma rotation on magnetohydrodynamic (MHD) modes and tokamak plasma stability is important for performance enhancement of current magnetic confinement experiments and to future fusion devices such as ITER. In order to control plasma rotation, two molybdenum electrodes have been installed on HBT-EP toroidally separated by 144 degrees. This allows independent biasing of the two probes both spatially and temporally. When the bias probes are inserted into the edge of the plasma and a voltage is applied, the probes drive radial currents and produce plasma flow from the torque induced by the currents. If the bias probe voltage is sufficiently positive, the MHD mode rotation transitions into a state with a rapid mode rotation frequency (in excess of 25 kHz) in the direction opposite to mode rotation without bias. The transition into this reversed rotation state occurs when the torque exceeds a threshold, which can depend upon the phase of an applied n = 1 error field. We present recent studies of the two-electrode system on mode rotation, mode stability, and the toroidal symmetry of the radial current through the scrape-off-layer (SOL) during MHD activity and applied magnetic perturbations. Supported by U.S. DOE Grant DE-FG02-86ER53222.
Modeling MHD Equilibrium and Dynamics with Non-Axisymmetric Resistive Walls in LTX and HBT-EP
NASA Astrophysics Data System (ADS)
Hansen, C.; Levesque, J.; Boyle, D. P.; Hughes, P.
2017-10-01
In experimental magnetized plasmas, currents in the first wall, vacuum vessel, and other conducting structures can have a strong influence on plasma shape and dynamics. These effects are complicated by the 3D nature of these structures, which dictate available current paths. Results from simulations to study the effect of external currents on plasmas in two different experiments will be presented: 1) The arbitrary geometry, 3D extended MHD code PSI-Tet is applied to study linear and non-linear plasma dynamics in the High Beta Tokamak (HBT-EP) focusing on toroidal asymmetries in the adjustable conducting wall. 2) Equilibrium reconstructions of the Lithium Tokamak eXperiment (LTX) in the presence of non-axisymmetric eddy currents. An axisymmetric model is used to reconstruct the plasma equilibrium, using the PSI-Tri code, along with a set of fixed 3D eddy current distributions in the first wall and vacuum vessel [C. Hansen et al., PoP Apr. 2017]. Simulations of detailed experimental geometries are enabled by use of the PSI-Tet code, which employs a high order finite element method on unstructured tetrahedral grids that are generated directly from CAD models. Further development of PSI-Tet and PSI-Tri will also be presented. This work supported by US DOE contract DE-SC0016256.
Exopolysaccharides enriched in rare sugars: bacterial sources, production, and applications
Roca, Christophe; Alves, Vitor D.; Freitas, Filomena; Reis, Maria A. M.
2015-01-01
Microbial extracellular polysaccharides (EPS), produced by a wide range of bacteria, are high molecular weight biopolymers, presenting an extreme diversity in terms of chemical structure and composition. They may be used in many applications, depending on their chemical and physical properties. A rather unexplored aspect is the presence of rare sugars in the composition of some EPS. Rare sugars, such as rhamnose or fucose, may provide EPS with additional biological properties compared to those composed of more common sugar monomers. This review gives a brief overview of these specific EPS and their producing bacteria. Cultivation conditions are summarized, demonstrating their impact on the EPS composition, together with downstream processing. Finally, their use in different areas, including cosmetics, food products, pharmaceuticals, and biomedical applications, are discussed. PMID:25914689
Modelling ion cyclotron emission from KSTAR tokamak and LHD helical device plasmas
NASA Astrophysics Data System (ADS)
Dendy, Richard; Chapman, Ben; Reman, Bernard; Chapman, Sandra; Akiyama, Tsuyoshi; Yun, Gunsu
2017-10-01
New high quality measurements of ion cyclotron emission (ICE) from KSTAR and LHD greatly extend the scope and diversity of plasma conditions under which ICE is observed. Variables include the origin (fusion reactions or neutral beam injection) and energy (sub- or super-Alfvénic) of the minority energetic ions that drive ICE; the composition of the bulk plasma (hydrogen or deuterium) which supports the modes excited; plasma density in the emitting region, and the timescale on which it changes; and toroidal magnetic field geometry (tokamak or helical device). Future exploitation of ICE as a diagnostic for energetic ion populations in JET D-T plasmas and in ITER rests on quantitative understanding of the physics of the emission. This is tested and extended by current KSTAR and LHD measurements of ICE. We report progress on direct numerical simulation using full orbit ion kinetic codes that solve the Maxwell-Lorentz equations for hundreds of millions of particles. In the saturated regime, these simulations yield excited field spectra that correspond directly to the measured ICE spectra under diverse KSTAR and LHD regimes. At early times, comparison of simulation outputs with linear analytical theory confirms the magnetoacoustic cyclotron instability as the basic driver of ICE. Supported by RCUK Energy Programme Grant EP/P012450/1, NRF Korea Grant 2014M1A7A1A03029881, NIFS budget ULHH029 and Euratom.
PREFACE: 24th Summer School and International Symposium on the Physics of Ionized Gases
NASA Astrophysics Data System (ADS)
Malović, Gordana; Popović, Luka Č.; Dimitrijević, Milan S.
2008-02-01
This volume of the Journal of Physics: Conference Series contains the Invited lectures, Topical invited lectures and Progress reports presented at the 24th Summer School and International Symposium on the Physics of Ionized Gases - SPIG 2008. The conference was held in Novi Sad, Serbia, 25-29 August 2008. Throughout the history of scientific discovery, one can see repeatedly how fundamental sciences have solved basic questions and opened new frontiers. In the field of physics, there are many key discoveries, resulting in their useful applications for the benefit of the mankind. It is very important to have meetings to discuss actual problems in particular fields of physics. This Conference provided a forum for 160 active researchers from 25 countries to discuss current advances in the physics of ionized gases and related fields. The Conference has a long tradition. Let us remember that the first SPIG was organized in 1968. The decay of former Yugoslavia in 1991, caused a disturbance in SPIG meetings, but fortunately, in 1993, SPIG meetings were successfully revitalized. During recent years we have met successively in Belgrade, Kotor, Zlatibor, Soko Banja, Tara, Kopaonik and finally this time in Novi Sad. The structure of the papers in this Proceedings is as follows: Atomic Collision Processes, Particle and Laser Beam Interactions with Solids, Low Temperature Plasmas and General Plasmas. We hope that this Proceedings will be an important source of information, first of all to students, and also to plasma physics scientists. First of all, we would like to thank to the invited speakers for participating at the SPIG 2008 and for their efforts writing contributions for this Proceedings. We also express our gratitude to the members of the Scientific and Organizing committees for their efforts in organizing the Conference. Especially we would like to thank the Ministry of Science and Technological Development of the Republic of Serbia for financial support. Also, this Conference was a conference sponsored by the European Physical Society (EPS). And finally we are grateful to all participants for useful contributions and useful discussions. Gordana Malović, Luka Č Popović and Milan S Dimitrijević
Hou, Jun; You, Guoxiang; Xu, Yi; Wang, Chao; Wang, Peifang; Miao, Lingzhan; Li, Yi; Ao, Yanhui; Lv, Bowen; Yang, Yangyang
2016-11-01
In this study, we examined the long-term effects of copper oxide nanoparticles (CuO NPs) on the production and properties of EPS and the resulting variations in surface physicochemical characteristics of biofilms in a sequencing batch biofilm reactor. After exposure to 50 mg/L CuO NPs for 45 days, the protein (PRO) and polysaccharide (PS) contents in loosely bound EPS (LB-EPS) decreased as the production of LB-EPS decreased from 34.4 to 30 mg TOC/g EPS. However, the production of tightly bound EPS (TB-EPS) increased by 16.47 % as the PRO and PS contents increased. The content of humic-like substances (HS) increased significantly, becoming the predominant constituent in EPS with the presence of 50 mg/L CuO NPs. Furthermore, the results of three-dimensional excitation-emission fluorescence spectra confirmed the various changes in terms of the LB-EPS and TB-EPS contents after exposure to CuO NPs. Fourier transform infrared spectroscopy showed that the -OH and -NH 2 groups of proteins in EPS were involved in the reaction with CuO NPs. Moreover, the chronic exposure to CuO NPs induced a negative impact on the flocculating efficiency of EPS and on the hydrophobicity and aggregation ability of microbial cells. The PRO/PS ratios of different EPS fractions were consistent with their hydrophobicities (R 2 >0.98) and bioflocculating efficiencies (R 2 >0.95); however, there was no correlation with aggregation ability. Additionally, the presence of bovine serum albumin (BSA) prevented the physical contact between CuO NPs and EPS as a result of NP aggregation and electrostatic repulsion.
NASA Astrophysics Data System (ADS)
Kang, Ming; Zhu, Weiren; Rukhlenko, Ivan D.
2017-12-01
The exceptional point (EP), which is one of the most important branch-type singularities exclusive to non-Hermitian systems, has been observed recently in various synthetic materials, giving rise to counterintuitive phenomena due to the nontrivial topology of the EP. Here, we present a direct experimental observation of the topological structure of the EPs via the angle-resolved transmission measurement of a hybridized metamaterial. Both eigenvalues and eigenvectors show branch-point singularities in the investigated biparametric space of frequency and incident angle. Importantly, the angle-resolved transmission coefficients provide all the information about the eigenvalues as well as the corresponding eigenvectors in the biparametric space, revealing the nontrivial topological structure of the EP, such as mode switching and the topological phase for a parameter loop encircling the EP. It is shown that the appearance of the EP in the scattering matrix is related directly to the perfect unidirectional transmission and the chirality of the EP corresponds to the maximum or minimum value of the asymmetric factor. Our investigation uncovers the capabilities of metamaterials for exploring the physics of EPs and their potential for having extreme optical properties, which provide potential applications in the spectral band ranging from microwaves to visible frequencies.
Ross, Ted M; Pereira, Lara E; Luckay, Amara; McNicholl, Janet M; García-Lerma, J Gerardo; Heneine, Walid; Eugene, Hermancia S; Pierce-Paul, Brooke R; Zhang, Jining; Hendry, R Michael; Smith, James M
2014-11-01
Vaccination and preexposure prophylaxis (PrEP) with antiretrovirals have shown only partial protection from HIV-1 infection in human trials. Oral Truvada (emtricitabine/tenofovir disoproxil fumarate) is FDA approved as PrEP but partial adherence reduces efficacy. If combined as biomedical preventions (CBP), an HIV vaccine could protect when PrEP adherence is low and PrEP could prevent vaccine breakthroughs. The efficacy of combining oral PrEP with an HIV vaccine has not been evaluated in humans. We determined the efficacy of combining a DNA/virus-like particle (VLP) vaccine with partially effective intermittent PrEP in Indian rhesus macaques (RM). Eight RM received intramuscular inoculations of five DNA plasmids encoding four HIV-1 Clade B primary isolate Envs and SIVmac239 Gag (at weeks 0 and 4), followed by intramuscular and intranasal inoculations of homologous Gag VLPs and four Env VLPs (at weeks 12, 16, and 53). At week 61, we initiated weekly rectal exposures with heterologous SHIV162p3 (10 TCID50) along with oral Truvada (TDF, 22 mg/kg; FTC 20 mg/kg) dosing 2 h before and 22 h after each exposure. This PrEP regimen previously demonstrated 50% efficacy. Five controls (no vaccine, no PrEP) received weekly SHIV162p3. All controls were infected after a median of four exposures; the mean peak plasma viral load (VL) was 3.9×10(7) vRNA copies/ml. CBP protected seven of eight (87.5%) RM. The one infected CBP RM had a reduced peak VL of 8.8×10(5) copies/ml. SHIV exposures during PrEP amplified Gag and Env antibody titers in protected RM. These results suggest that combining oral PrEP with HIV vaccines could enhance protection against HIV-1 infection.
Equivalence principle and quantum mechanics: quantum simulation with entangled photons.
Longhi, S
2018-01-15
Einstein's equivalence principle (EP) states the complete physical equivalence of a gravitational field and corresponding inertial field in an accelerated reference frame. However, to what extent the EP remains valid in non-relativistic quantum mechanics is a controversial issue. To avoid violation of the EP, Bargmann's superselection rule forbids a coherent superposition of states with different masses. Here we suggest a quantum simulation of non-relativistic Schrödinger particle dynamics in non-inertial reference frames, which is based on the propagation of polarization-entangled photon pairs in curved and birefringent optical waveguides and Hong-Ou-Mandel quantum interference measurement. The photonic simulator can emulate superposition of mass states, which would lead to violation of the EP.
NASA Astrophysics Data System (ADS)
Carmona, A.; Poveda, G.; Sivapalan, M.; Vallejo-Bernal, S. M.; Bustamante, E.
2015-12-01
We study a 3-D generalization of Budyko's framework that involves the complementary relationship between long-term mean actual evapotranspiration (E) and potential evapotranspiration (Ep), and that captures the mutual interdependence among E, Ep, and mean annual precipitation (P). For this purpose we use three dimensionless and dependent quantities: Ψ=E/P, Φ=Ep/P and Ω=E/Ep. We demonstrate analytically that Budyko-type equations are unable to capture the physical limit of the relation between Ω and Φ in humid environments, owing to the unfeasibility of Ep/P→0 at E/Ep=1. Using independent datasets from 146 sub-catchments in the Amazon River basin we overcome this physical inconsistency by proposing a physically consistent power law Ψ=kΦ e with pre-factor k=0.66 and scaling exponent e=0.83 (R2=0.93). The proposed power law is compared with other Budyko-type equations, namely those by Yang et al (2008) and Cheng et al (2011). Taking into account the goodness of fits with confidence bounds set at 95% level and the ability to comply with the physical limits of the 3-D space, our results show that the power law works better to model the long-term water and energy balances within the Amazon River basin. At the interannual time scale, parameters from the three studied equations are estimated for each catchment using 27 years of information and interesting regional patterns emerge, as well as evidence of space-time symmetry. In addition, results show that within individual catchments the parameters from the linear relationship by Cheng et al (2011) and from the power law resemble and are related to the partitioning of energy via evapotranspiration in terms of Ω. Finally, signs of co-evolution of catchments are explored by linking the emerging spatial patterns of the parameters with landscape properties that represent some of the main features of the Amazon River basin, including topography, water in soils and vegetation.
Hyun, Kyung-A; Koo, Gi-Bang; Han, Hyunju; Sohn, Joohyuk; Choi, Wonshik; Kim, Seung-Il; Jung, Hyo-Il; Kim, You-Sun
2016-04-26
The dissemination of circulating tumor cells (CTCs) requires the Epithelial-to-Mesenchymal transition (EMT), in which cells lose their epithelial characteristics and acquire more mesenchymal-like phenotypes. Current isolation of CTCs relies on affinity-based approaches reliant on the expression of Epithelial Cell Adhesion Molecule (EpCAM). Here we show EMT-induced breast cancer cells maintained in prolonged mammosphere culture conditions possess increased EMT markers and cancer stem cell markers, as well as reduced cell mass and size by quantitative phase microscopy; however, EpCAM expression is dramatically decreased in these cells. Moreover, CTCs isolated from breast cancer patients using a label-free microfluidic flow fractionation device had differing expression patterns of EpCAM, indicating that affinity approaches reliant on EpCAM expression may underestimate CTC number and potentially miss critical subpopulations. Further characterization of CTCs, including low-EpCAM populations, using this technology may improve detection techniques and cancer diagnosis, ultimately improving cancer treatment.
Mizuno, Ju; Takahashi, Toru
2016-01-01
Well-leg compartment syndrome (WLCS) is one of the catastrophic complications related to prolonged surgical procedures performed in the lithotomy position, using a knee-crutch-type leg holder (KCLH) system, to support the popliteal fossae and calf regions. Obesity has been implicated as a risk factor in the lithotomy position-related WLCS during surgery. In the present study, we investigated the relationship between the external pressure (EP) applied to the calf region using a KCLH system in the lithotomy position and selected physical characteristics. Twenty-one young, healthy volunteers (21.4±0.5 years of age, eleven males and ten females) participated in this study. The KCLH system used was Knee Crutch(®). We assessed four types of EPs applied to the calf region: box pressure, peak box pressure, contact pressure, and peak contact pressure, using pressure-distribution measurement system (BIG-MAT(®)). Relationships between these four EPs to the calf regions of both lower legs and a series of physical characteristics (sex, height, weight, and body mass index [BMI]) were analyzed. All four EPs applied to the bilateral calf regions were higher in males than in females. For all subjects, significant positive correlations were observed between all four EPs and height, weight, and BMI. EP applied to the calf region is higher in males than in females when the subject is supported by a KCLH system in the lithotomy position. In addition, EP increases with the increase in height, weight, and BMI. Therefore, male sex, height, weight, and BMI may contribute to the risk of inducing WLCS.
Scrape-off-layer characterization and current-control of kink modes in HBT-EP
NASA Astrophysics Data System (ADS)
Brooks, John; Stewart, Ian; Levesque, Jeffrey; Mauel, Mike; Navratil, Gerald
2017-10-01
Scrape-off layer (SOL) currents and their paths through tokamaks are not well understood, but their control may prove crucial to the success of ITER and future fusion energy devices. We extend Columbia University's High Beta Tokamak-Extended Pulse (HBT-EP) experiment and active GPU feedback system to study the SOL and control MHD kink instabilities by actively controlling these currents. First, the radial plasma profiles and the edge structure of kink instabilities are measured with two triple probes. Second, we use active feedback control of a radially adjustable biased electrode to change the rotation and magnitude of slowly growing kink instabilities. By changing the phase between the probe's voltage and the edge instability with active feedback, we study its ability to influence and control plasma MHD structures. This work is in preparation for a planned 2018 multi-electrode SOL control upgrade. Supported by U.S. DOE Grant DE-FG02-86ER53222.
Vajapeyam, S; Stamoulis, C; Ricci, K; Kieran, M; Poussaint, T Young
2017-01-01
Pharmacokinetic parameters from dynamic contrast-enhanced MR imaging have proved useful for differentiating brain tumor grades in adults. In this study, we retrospectively reviewed dynamic contrast-enhanced perfusion data from children with newly diagnosed brain tumors and analyzed the pharmacokinetic parameters correlating with tumor grade. Dynamic contrast-enhanced MR imaging data from 38 patients were analyzed by using commercially available software. Subjects were categorized into 2 groups based on pathologic analyses consisting of low-grade (World Health Organization I and II) and high-grade (World Health Organization III and IV) tumors. Pharmacokinetic parameters were compared between the 2 groups by using linear regression models. For parameters that were statistically distinct between the 2 groups, sensitivity and specificity were also estimated. Eighteen tumors were classified as low-grade, and 20, as high-grade. Transfer constant from the blood plasma into the extracellular extravascular space (K trans ), rate constant from extracellular extravascular space back into blood plasma (K ep ), and extracellular extravascular volume fraction (V e ) were all significantly correlated with tumor grade; high-grade tumors showed higher K trans , higher K ep , and lower V e . Although all 3 parameters had high specificity (range, 82%-100%), K ep had the highest specificity for both grades. Optimal sensitivity was achieved for V e , with a combined sensitivity of 76% (compared with 71% for K trans and K ep ). Pharmacokinetic parameters derived from dynamic contrast-enhanced MR imaging can effectively discriminate low- and high-grade pediatric brain tumors. © 2017 by American Journal of Neuroradiology.
Heavy ion charge-state distribution effects on energy loss in plasmas.
Barriga-Carrasco, Manuel D
2013-10-01
According to dielectric formalism, the energy loss of the heavy ion depends on its velocity and its charge density. Also, it depends on the target through its dielectric function; here the random phase approximation is used because it correctly describes fully ionized plasmas at any degeneracy. On the other hand, the Brandt-Kitagawa (BK) model is employed to depict the projectile charge space distribution, and the stripping criterion of Kreussler et al. is used to determine its mean charge state [Q]. This latter criterion implies that the mean charge state depends on the electron density and temperature of the plasma. Also, the initial charge state of the heavy ion is crucial for calculating [Q] inside the plasma. Comparing our models and estimations with experimental data, a very good agreement is found. It is noticed that the energy loss in plasmas is higher than that in the same cold gas cases, confirming the well-known enhanced plasma stopping (EPS). In this case, EPS is only due to the increase in projectile effective charge Q(eff), which is obtained as the ratio between the energy loss of each heavy ion and that of the proton in the same plasma conditions. The ratio between the effective charges in plasmas and in cold gases is higher than 1, but it is not as high as thought in the past. Finally, another significant issue is that the calculated effective charge in plasmas Q(eff) is greater than the mean charge state [Q], which is due to the incorporation of the BK charge distribution. When estimations are performed without this distribution, they do not fit well with experimental data.
The European Physical Society Conference on High Energy Physics
NASA Astrophysics Data System (ADS)
2017-07-01
The European Physical Society Conference on High Energy Physics (EPS- HEP) is one of the major international conferences that review the field. It takes place every other year since 1971. It is organized by the High Energy and Particle Physics Division of the European Physical Society in cooperation with an appointed European Local Institute of Research or an internationally recognized University or Academy Body. EPS-HEP 2017 was held on 5-12 July in Venice, Italy at Palazzo del Cinema and Palazzo del Casinò, located in the Lido island. The conference has been organized by the Istituto Nazionale di Fisica Nucleare (INFN) and by the Department of Physics and Astronomy of the University of Padova. Editorial Board: Paolo Checchia, Mauro Mezzetto, Giuseppina Salente, Michele Doro, Livia Conti, Caterina Braggio, Chiara Sirignano, Andrea Dainese, Martino Margoni, Roberto Rossin, Pierpaolo Mastrolia, Patrizia Azzi, Enrico Conti, Marco Zanetti, Luca Martucci, Sofia Talas Lucano Canton.
Lin, C-S; Hsu, M-Y F; Chong, C-F
2008-07-01
Conveying empathy is a multi-phase process involving an inner resonation phase, communication phase, and reception phase. Previous investigations on physician empathy have focused on a physician's inner resonation phase or communication phase and not on the patient's reception phase. The purpose of this study was to investigate the differences in the perception of physicians' empathy between emergency physicians (EPs) and their patients. The answer to this question will allow us to more fully understand all phases of empathy and will help guide the teaching of how to effectively communicate empathy in the clinical setting. From 2004 to 2005, we conducted in-depth, semi-structured interviews with 7 each of EPs, patients, patients' family members and nurses. A phenomenological approach was used to analyze the data. Four themes emerged from the analysis: (1) When patients expressed their feelings, EPs usually did not resonate with their concerns; (2) Patients needed EPs to provide psychological comfort, but EPs focused only on patients' physical discomfort; (3) Patients needed appropriate feedback from EPs, but EPs did not reflect on whether their patients had received empathy from them; (4) EPs' ability to empathize was affected by environmental factors, which EPs found difficult to overcome. EPs and their patients perceive the physicians' empathy differently. These findings provide insights into patients' perceptions of their physicians' empathic expressions and provide a framework for teaching physicians how to convey empathy in the emergency department setting.
EP2 receptors mediate airway relaxation to substance P, ATP, and PGE2.
Fortner, C N; Breyer, R M; Paul, R J
2001-08-01
Substance P (SP) and ATP evoke transient, epithelium-dependent relaxation of constricted mouse tracheal smooth muscle. Relaxation to either SP or ATP is blocked by indomethacin, but the specific eicosanoid(s) involved have not been definitively identified. SP and ATP are reported to release PGE2 from airway epithelium in other species, suggesting PGE2 as a likely mediator in epithelium-dependent airway relaxation. Using mice homozygous for a gene-targeted deletion of the EP2 receptor [EP2(-/-)], one of the PGE2 receptors, we tested the hypothesis that PGE2 is the primary mediator of relaxation to SP or ATP. Relaxation in response to SP or ATP was significantly reduced in tracheas from EP2(-/-) mice. There were no differences between EP2(-/-) and wild-type tracheas in their physical dimensions, contraction to ACh, or relaxation to isoproterenol, thus ruling out any general alterations of smooth muscle function. There were also no differences between EP2(-/-) and wild-type tracheas in basal or stimulated PGE2 production. Exogenous PGE2 produced significantly less relaxation in EP2(-/-) tracheas compared with the wild type. Taken together, this experimental evidence supports the following two conclusions: EP2 receptors are of primary importance in airway relaxation to PGE2 and relaxation to SP or ATP is mediated through PGE2 acting on EP2 receptors.
Progress towards a laser produced relativistic electron-positron pair plasma
Chen, Hui; Bonlie, J.; Cauble, R.; ...
2016-04-01
Here, a set of experiments has been performed exploring unique characteristics of pair jets and plasmas at several energetic short-pulse laser facilities including Titan at Livermore and OMEGA EP in Rochester, as well as the Osaka LFEX and AWE Orion lasers. New results are summarized, including positron beam emittance, scaling of pair production vs. laser energy, and initial results on the pair jet collimation using electromagnetic fields.
NASA Astrophysics Data System (ADS)
O'Connell, Deborah; Hirst, A. M.; Packer, J. R.; Simms, M. S.; Mann, V. M.; Frame, F. M.; Maitland, N. J.
2016-09-01
Atmospheric pressure plasmas have shown considerable promise as a potential cancer therapy. An atmospheric pressure plasma driven with kHz kV excitation, operated with helium and oxygen admixtures is used to investigate the interaction with prostate cancer cells. The cytopathic effect was verified first in two commonly used prostate cancer cell lines (BPH-1 and PC-3 cells) and further extended to examine the effects in paired normal and tumour prostate epithelial cells cultured directly from patient tissues. Through the formation of reactive species in cell culture media, and potentially other plasma components, we observed high levels of DNA damage, together with reduced cell viability and colony-forming ability. We observed differences in response between the prostate cell lines and primary cells, particularly in terms of the mechanism of cell death. The primary cells ultimately undergo necrotic cell death in both the normal and tumour samples, in the complete absence of apoptosis. In addition, we provide the first evidence of an autophagic response in primary cells. This work highlights the importance of studying primary cultures in order to gain a more realistic insight into patient efficacy. EPSRC EP/H003797/1 & EP/K018388/1, Yorkshire Cancer Research: YCR Y257PA.
Low-density plasma formation in aqueous biological media using sub-nanosecond laser pulses
NASA Astrophysics Data System (ADS)
Genc, Suzanne L.; Ma, Huan; Venugopalan, Vasan
2014-08-01
We demonstrate the formation of low- and high-density plasmas in aqueous media using sub-nanosecond laser pulses delivered at low numerical aperture (NA = 0.25). We observe two distinct regimes of plasma formation in deionized water, phosphate buffered saline, Minimum Essential Medium (MEM), and MEM supplemented with phenol red. Optical breakdown is first initiated in a low-energy regime and characterized by bubble formation without plasma luminescence with threshold pulse energies in the range of Ep ≈ 4-5 μJ, depending on media formulation. The onset of this regime occurs over a very narrow interval of pulse energies and produces small bubbles (Rmax = 2-20 μm) due to a tiny conversion (η < 0.01%) of laser energy to bubble energy EB. The lack of visible plasma luminescence, sharp energy onset, and low bubble energy conversion are all hallmarks of low-density plasma (LDP) formation. At higher pulse energies (Ep = 11-20 μJ), the process transitions to a second regime characterized by plasma luminescence and large bubble formation. Bubbles formed in this regime are 1-2 orders of magnitude larger in size ( R max ≳ 100 μ m ) due to a roughly two-order-of-magnitude increase in bubble energy conversion (η ≳ 3%). These characteristics are consistent with high-density plasma formation produced by avalanche ionization and thermal runaway. Additionally, we show that supplementation of MEM with fetal bovine serum (FBS) limits optical breakdown to this high-energy regime. The ability to produce LDPs using sub-nanosecond pulses focused at low NA in a variety of cell culture media formulations without FBS can provide for cellular manipulation at high throughput with precision approaching that of femtosecond pulses delivered at high NA.
Blagus, Tanja; Markelc, Bostjan; Cemazar, Maja; Kosjek, Tina; Preat, Veronique; Miklavcic, Damijan; Sersa, Gregor
2013-12-28
Electroporation (EP) is a physical method for the delivery of molecules into cells and tissues, including the skin. In this study, in order to control the degree of transdermal and topical drug delivery, EP at different amplitudes of electric pulses was evaluated. A new in vivo real-time monitoring system based on fluorescently labeled molecules was developed, for the quantification of transdermal and topical drug delivery. EP of the mouse skin was performed with new non-invasive multi-array electrodes, delivering different amplitudes of electric pulses ranging from 70 to 570 V, between the electrode pin pairs. Patches, soaked with 4 kDa fluorescein-isothiocyanate labeled dextran (FD), doxorubicin (DOX) or fentanyl (FEN), were applied to the skin before and after EP. The new monitoring system was developed based on the delivery of FD to and through the skin. FD relative quantity was determined with fluorescence microscopy imaging, in the treated region of the skin for topical delivery and in a segment of the mouse tail for transdermal delivery. The application of electric pulses for FD delivery resulted in enhanced transdermal delivery. Depending on the amplitude of electric pulses, it increased up to the amplitude of 360 V, and decreased at higher amplitudes (460 and 570 V). Topical delivery steadily enhanced with increasing the amplitude of the delivered electric pulses, being even higher than after tape stripping used as a positive control. The non-invasive monitoring of the delivery of DOX, a fluorescent chemotherapeutic drug, qualitatively and quantitatively confirmed the effects of EP at 360 and 570 V pulse amplitudes on topical and transdermal drug delivery. Delivery of FEN at 360 and 570 V pulse amplitudes verified the observed effects as obtained with FD and DOX, by the measured physiological responses of the mice as well as FEN plasma concentration. This study demonstrates that with the newly developed non-invasive multi-array electrodes and with the varying electric pulse amplitude, the amount of topical and transdermal drug delivery to the skin can be controlled. Furthermore, the newly developed monitoring system provides a tool for rapid real-time determination of both, transdermal and topical delivery, when the delivered molecule is fluorescent. © 2013 Elsevier B.V. All rights reserved.
Wang, Lee-Min; How, Chorng-Kuang; Yang, Ming-Chin; Su, Syi
2013-01-01
Objective To investigate the reasons for the occurrence of clinically significant adverse events (CSAEs) in emergency department-discharged patients through emergency physicians' (EPs) subjective reasoning and senior EPs' objective evaluation. Design This was a combined prospective follow-up and retrospective review of cases of consecutive adult non-traumatic patients who presented to a tertiary-care emergency department in Taiwan between 1 September 2005 and 31 July 2006. Data were extracted from ‘on-duty EPs' subjective reasoning for discharging patients with CSAEs (study group) and without CSAEs (control group)’ and ‘objective evaluation of CSAEs by senior EPs, using clinical evidences such as recording history, physical examinations, laboratory/radiological examinations and observation of inadequacies in the basic management process (such as recording history, physical examinations, laboratory/radiological examinations and observation) as the guide’. Subjective reasons for discharging patients’ improvement of symptoms, and the certainty of safety of the discharge were compared in the two groups using χ2 statistics or t test. Results Of the 20 512 discharged cases, there were 1370 return visits (6.7%, 95% CI 6.3% to 7%) and 165 CSAEs due to physicians' factors (0.82%, 95% CI 0.75% to 0.95%). In comparisons between the study group and the control group, only some components of discharge reasoning showed a significant difference (p<0.001). Inadequacies in the basic management process were the main cause of CSAEs (164/165). Conclusion The authors recommended that EP follow-up of the basic management processes (including history record, physical examination, laboratory and radiological examinations, clinical symptoms/signs and treatment) using clinical evidence as a guideline should be made mandatory. PMID:22433586
Hormonal Contraception, Body Water Balance and Thermoreregulation
1999-10-01
were independent of changes in plasma volume. We have begun testing the impact of OC P and OC E+P on osmotic regulation of AVP during hypertonic saline infusion, but have completed only three subjects so have no comment at this point.
Channel optimization of high-intensity laser beams in millimeter-scale plasmas.
Ceurvorst, L; Savin, A; Ratan, N; Kasim, M F; Sadler, J; Norreys, P A; Habara, H; Tanaka, K A; Zhang, S; Wei, M S; Ivancic, S; Froula, D H; Theobald, W
2018-04-01
Channeling experiments were performed at the OMEGA EP facility using relativistic intensity (>10^{18}W/cm^{2}) kilojoule laser pulses through large density scale length (∼390-570 μm) laser-produced plasmas, demonstrating the effects of the pulse's focal location and intensity as well as the plasma's temperature on the resulting channel formation. The results show deeper channeling when focused into hot plasmas and at lower densities, as expected. However, contrary to previous large-scale particle-in-cell studies, the results also indicate deeper penetration by short (10 ps), intense pulses compared to their longer-duration equivalents. This new observation has many implications for future laser-plasma research in the relativistic regime.
Channel optimization of high-intensity laser beams in millimeter-scale plasmas
NASA Astrophysics Data System (ADS)
Ceurvorst, L.; Savin, A.; Ratan, N.; Kasim, M. F.; Sadler, J.; Norreys, P. A.; Habara, H.; Tanaka, K. A.; Zhang, S.; Wei, M. S.; Ivancic, S.; Froula, D. H.; Theobald, W.
2018-04-01
Channeling experiments were performed at the OMEGA EP facility using relativistic intensity (>1018W/cm 2 ) kilojoule laser pulses through large density scale length (˜390 -570 μ m ) laser-produced plasmas, demonstrating the effects of the pulse's focal location and intensity as well as the plasma's temperature on the resulting channel formation. The results show deeper channeling when focused into hot plasmas and at lower densities, as expected. However, contrary to previous large-scale particle-in-cell studies, the results also indicate deeper penetration by short (10 ps), intense pulses compared to their longer-duration equivalents. This new observation has many implications for future laser-plasma research in the relativistic regime.
Similar simulation study on the characteristics of the electric potential response to coal mining
NASA Astrophysics Data System (ADS)
Niu, Yue; Li, Zhonghui; Kong, Biao; Wang, Enyuan; Lou, Quan; Qiu, Liming; Kong, Xiangguo; Wang, Jiali; Dong, Mingfu; Li, Baolin
2018-02-01
An electric potential (EP) can be generated during the failure process of coal and rock. In this article, a similar physical model of coal rock was built and the characteristics of the EP responding to the process of coal mining were studied. The results showed that, at the early mining stage, the structure of coal rock strata were stable in the simulation model, the support stress of overlying coal rock strata was low and the maximum subsidence was little, while the EP change was less. With the advancement of the working face, the support stress of the overlying coal rock strata in the mined-out area changed dramatically, the maximum subsidence increased constantly, the deformation and destruction were aggravated, and cracks expanded continuously. Meanwhile, the EP response was significant with fluctuation. When significant macro damage appeared in coal rock strata, the EP signal fluctuation was violent. The overlying coal rock strata were influenced by gravity and mining activity. During the mining process, the crack growth and the friction, together with slip between coal and rock particles, resulted in the response of EP. The change in EP was closely related to the damage state and stress distribution of the coal rock strata. EP monitoring has the advantages of accurate reflection and strong anti-interference in the field. Therefore, with further study, an EP monitoring method could be applied for monitoring and early warning of coal and rock dynamic disaster, and risk evaluation in the future. The strength of the EP and its fluctuation degree could serve as the key discrimination indexes.
Evolution of Motor Control: From Reflexes and Motor Programs to the Equilibrium-Point Hypothesis.
Latash, Mark L
2008-01-01
This brief review analyzes the evolution of motor control theories along two lines that emphasize active (motor programs) and reactive (reflexes) features of voluntary movements. It suggests that the only contemporary hypothesis that integrates both approaches in a fruitful way is the equilibrium-point hypothesis. Physical, physiological, and behavioral foundations of the EP-hypothesis are considered as well as relations between the EP-hypothesis and the recent developments of the notion of motor synergies. The paper ends with a brief review of the criticisms of the EP-hypothesis and challenges that the hypothesis faces at this time.
Microbial biofilms in intertidal systems: an overview
NASA Astrophysics Data System (ADS)
Decho, Alan W.
2000-07-01
Intertidal marine systems are highly dynamic systems which are characterized by periodic fluctuations in environmental parameters. Microbial processes play critical roles in the remineralization of nutrients and primary production in intertidal systems. Many of the geochemical and biological processes which are mediated by microorganisms occur within microenvironments which can be measured over micrometer spatial scales. These processes are localized by cells within a matrix of extracellular polymeric secretions (EPS), collectively called a "microbial biofilm". Recent examinations of intertidal systems by a range of investigators using new approaches show an abundance of biofilm communities. The purpose of this overview is to examine recent information concerning the roles of microbial biofilms in intertidal systems. The microbial biofilm is a common adaptation of natural bacteria and other microorganisms. In the fluctuating environments of intertidal systems, biofilms form protective microenvironments and may structure a range of microbial processes. The EPS matrix of biofilm forms sticky coatings on individual sediment particles and detrital surfaces, which act as a stabilizing anchor to buffer cells and their extracellular processes during the frequent physical stresses (e.g., changes in salinity and temperature, UV irradiation, dessication). EPS is an operational definition designed to encompass a range of large microbially-secreted molecules having widely varying physical and chemical properties, and a range of biological roles. Examinations of EPS using Raman and Fourier-transform infared spectroscopy, and atomic-force microscopy suggest that some EPS gels possess physical and chemical properties which may hasten the development of sharp geochemical gradients, and contribute a protective effect to cells. Biofilm polymers act as a sorptive sponge which binds and concentrates organic molecules and ions close to cells. Concurrently, the EPS appear to localize extracellular enzyme activities of bacteria, and hence contribute to the efficient biomineralization of organics. At larger spatial scales, the copious secretion of specific types of EPS by diatoms on the surfaces of intertidal mudflats may stabilize sediments against resuspension. Biofilms exert important roles in environmental- and public health processes occurring within intertidal systems. The sorptive properties of EPS effectively chelate toxic metals and other contaminants, which then act as an efficient trophic-transfer vehicle for the entry of contaminants into food webs. In the water column, biofilm microenvironments in suspended flocs may form a stabilizing refugia that enhances the survival and propagation of pathogenic (i.e., disease-causing) bacteria entering coastal waters from terrestrial and freshwater sources. The EPS matrix affords microbial cells a tremendous potential for resiliency during periods of stress, and may enhance the overall physiological activities of bacteria. It is emphasized here that the influences of small-scale microbial biofilms must be addressed in understanding larger-scale processes within intertidal systems.
Broad-scale predictability of carbohydrates and exopolymers in Antarctic and Arctic sea ice
Underwood, Graham J. C.; Aslam, Shazia N.; Michel, Christine; Niemi, Andrea; Norman, Louiza; Meiners, Klaus M.; Laybourn-Parry, Johanna; Paterson, Harriet; Thomas, David N.
2013-01-01
Sea ice can contain high concentrations of dissolved organic carbon (DOC), much of which is carbohydrate-rich extracellular polymeric substances (EPS) produced by microalgae and bacteria inhabiting the ice. Here we report the concentrations of dissolved carbohydrates (dCHO) and dissolved EPS (dEPS) in relation to algal standing stock [estimated by chlorophyll (Chl) a concentrations] in sea ice from six locations in the Southern and Arctic Oceans. Concentrations varied substantially within and between sampling sites, reflecting local ice conditions and biological content. However, combining all data revealed robust statistical relationships between dCHO concentrations and the concentrations of different dEPS fractions, Chl a, and DOC. These relationships were true for whole ice cores, bottom ice (biomass rich) sections, and colder surface ice. The distribution of dEPS was strongly correlated to algal biomass, with the highest concentrations of both dEPS and non-EPS carbohydrates in the bottom horizons of the ice. Complex EPS was more prevalent in colder surface sea ice horizons. Predictive models (validated against independent data) were derived to enable the estimation of dCHO concentrations from data on ice thickness, salinity, and vertical position in core. When Chl a data were included a higher level of prediction was obtained. The consistent patterns reflected in these relationships provide a strong basis for including estimates of regional and seasonal carbohydrate and dEPS carbon budgets in coupled physical-biogeochemical models, across different types of sea ice from both polar regions. PMID:24019487
Broad-scale predictability of carbohydrates and exopolymers in Antarctic and Arctic sea ice.
Underwood, Graham J C; Aslam, Shazia N; Michel, Christine; Niemi, Andrea; Norman, Louiza; Meiners, Klaus M; Laybourn-Parry, Johanna; Paterson, Harriet; Thomas, David N
2013-09-24
Sea ice can contain high concentrations of dissolved organic carbon (DOC), much of which is carbohydrate-rich extracellular polymeric substances (EPS) produced by microalgae and bacteria inhabiting the ice. Here we report the concentrations of dissolved carbohydrates (dCHO) and dissolved EPS (dEPS) in relation to algal standing stock [estimated by chlorophyll (Chl) a concentrations] in sea ice from six locations in the Southern and Arctic Oceans. Concentrations varied substantially within and between sampling sites, reflecting local ice conditions and biological content. However, combining all data revealed robust statistical relationships between dCHO concentrations and the concentrations of different dEPS fractions, Chl a, and DOC. These relationships were true for whole ice cores, bottom ice (biomass rich) sections, and colder surface ice. The distribution of dEPS was strongly correlated to algal biomass, with the highest concentrations of both dEPS and non-EPS carbohydrates in the bottom horizons of the ice. Complex EPS was more prevalent in colder surface sea ice horizons. Predictive models (validated against independent data) were derived to enable the estimation of dCHO concentrations from data on ice thickness, salinity, and vertical position in core. When Chl a data were included a higher level of prediction was obtained. The consistent patterns reflected in these relationships provide a strong basis for including estimates of regional and seasonal carbohydrate and dEPS carbon budgets in coupled physical-biogeochemical models, across different types of sea ice from both polar regions.
Irungu, Elizabeth M; Heffron, Renee; Mugo, Nelly; Ngure, Kenneth; Katabira, Elly; Bulya, Nulu; Bukusi, Elizabeth; Odoyo, Josephine; Asiimwe, Stephen; Tindimwebwa, Edna; Celum, Connie; Baeten, Jared M
2016-10-17
Antiretroviral therapy (ART) and pre-exposure prophylaxis (PrEP) reduce HIV-1 transmission within heterosexual HIV-1 serodiscordant couples. Prioritizing couples at highest HIV-1 transmission risk for ART and PrEP would maximize impact and minimize costs. The Partners Demonstration Project is an open-label, delivery study of integrated PrEP and ART for HIV-1 prevention among high risk HIV-1 serodiscordant couples in Kenya and Uganda. We evaluated the feasibility of using a validated risk score that weighs a combination of easily measurable factors (age, children, marital status, male circumcision status, condom use, plasma HIV-1 levels) to identify couples at highest risk for HIV-1 transmission for enrollment. Couples scoring ≥5 met the risk score eligibility criteria. We screened 1694 HIV-1 serodiscordant couples and enrolled 1013. Of the screened couples, 1331 (78.6 %) scored ≥5 (with an expected incidence >3 % per year) and 76 % of these entered the study. The median age of the HIV-1 uninfected partner was 29 years [IQR 26, 36] and 20 % were <25 years of age. The HIV-1 uninfected partner was male in 67 % of partnerships, 33 % of whom were uncircumcised, 57 % of couples had no children, and 65 % reported unprotected sex in the month prior to enrollment. Among HIV-1 infected partners, 41 % had plasma viral load >50,000 copies/ml. A risk scoring tool identified HIV-1 serodiscordant couples for a demonstration project of PrEP and ART with high HIV-1 risk. The tool may be feasible for research and public health settings to maximize efficiency and minimize HIV-1 prevention costs.
Körzendörfer, Adrian; Nöbel, Stefan; Hinrichs, Jörg
2017-07-01
Two major quality defects of yogurt are syneresis and the presence of large particles, and several reasons have been extensively discussed. Vibrations during fermentation, particularly generated by pumps, must be considered as a further cause as latest research showed that both ultrasound and low frequencies induced visible particles. The aim of this study was to investigate the impact of sonication during fermentation with starter cultures differing in exopolysaccharide (EPS) synthesis on the physical properties of set (syneresis, firmness) and stirred yogurt (large particles, laser diffraction, rheology). Skim milk was fermented with starter cultures YC-471 (low EPS) or YF-L 901 (high EPS) (Chr. Hansen) and sonicated for 5min at pH5.2. Sonicated set gels exhibited syneresis and were softer than respective controls. The mechanical treatment was adjusted to quantify visible particles (d≥0.9mm) in stirred yogurts properly. Sonication significantly increased particle numbers, however, the effect was less pronounced when YF-L 901 was used, indicating EPS as a tool to reduce syneresis and particle formation due to vibrations. Rheological parameters and size of microgel particles were rather influenced by starter cultures than by sonication. Copyright © 2017 Elsevier Ltd. All rights reserved.
Shi, Ju; Johansson, Jenny; Woodling, Nathaniel S; Wang, Qian; Montine, Thomas J; Andreasson, Katrin
2010-06-15
Peripheral inflammation leads to immune responses in brain characterized by microglial activation, elaboration of proinflammatory cytokines and reactive oxygen species, and secondary neuronal injury. The inducible cyclooxygenase (COX), COX-2, mediates a significant component of this response in brain via downstream proinflammatory PG signaling. In this study, we investigated the function of the PGE2 E-prostanoid (EP) 4 receptor in the CNS innate immune response to the bacterial endotoxin LPS. We report that PGE2 EP4 signaling mediates an anti-inflammatory effect in brain by blocking LPS-induced proinflammatory gene expression in mice. This was associated in cultured murine microglial cells with decreased Akt and I-kappaB kinase phosphorylation and decreased nuclear translocation of p65 and p50 NF-kappaB subunits. In vivo, conditional deletion of EP4 in macrophages and microglia increased lipid peroxidation and proinflammatory gene expression in brain and in isolated adult microglia following peripheral LPS administration. Conversely, EP4 selective agonist decreased LPS-induced proinflammatory gene expression in hippocampus and in isolated adult microglia. In plasma, EP4 agonist significantly reduced levels of proinflammatory cytokines and chemokines, indicating that peripheral EP4 activation protects the brain from systemic inflammation. The innate immune response is an important component of disease progression in a number of neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. In addition, recent studies demonstrated adverse vascular effects with chronic administration of COX-2 inhibitors, indicating that specific PG signaling pathways may be protective in vascular function. This study supports an analogous and beneficial effect of PGE2 EP4 receptor signaling in suppressing brain inflammation.
Measurement of scrape-off-layer current dynamics during MHD activity and disruptions in HBT-EP
NASA Astrophysics Data System (ADS)
Levesque, J. P.; Brooks, J. W.; Abler, M. C.; Bialek, J.; Byrne, P. J.; Hansen, C. J.; Hughes, P. E.; Mauel, M. E.; Navratil, G. A.; Rhodes, D. J.
2017-08-01
We report scrape-off layer (SOL) current measurements during magnetohydrodynamic (MHD) mode activity, resonant magnetic perturbations (RMPs), and disruptions in the High Beta Tokamak—Extended Pulse (HBT-EP) device. Currents are measured via segmented plasma current Rogowski coils, jumpers running toroidally between otherwise-isolated vessel sections, and a grounded electrode in the scrape-off layer. These currents strongly depend on the plasma’s major radius, and amplitude and phase of non-axisymmetric field components. SOL currents connecting through the vessel are seen to reach ∼0.2{--}0.5 % of the plasma current during typical kink activity and RMPs. Plasma current asymmetries and scrape-off-layer currents generated during disruptions, which are commonly called halo currents, reach ∼4 % of I p. Asymmetric toroidal currents between vessel sections rotate at tens of kHz through most of the current quench, then symmetrize once I p reaches ∼30 % of its pre-disruptive value. Toroidal jumper currents oscillate between co- and counter-I p, with co-I p being dominant on average during disruptions. A relative increase in local plasma current measured by a segmented I p Rogowski coil correlates with counter-I p current in the nearest toroidal jumper. Measurements are interpreted in the context of two models that produce contrary predictions for the toroidal vessel current polarity during disruptions. Plasma current asymmetry measurements are consistent with both models, and SOL currents scale with plasma displacement toward the vessel wall. The design of an upcoming SOL current diagnostic and control upgrade is also briefly presented.
MHD Simulations of Plasma Dynamics with Non-Axisymmetric Boundaries
NASA Astrophysics Data System (ADS)
Hansen, Chris; Levesque, Jeffrey; Morgan, Kyle; Jarboe, Thomas
2015-11-01
The arbitrary geometry, 3D extended MHD code PSI-TET is applied to linear and non-linear simulations of MCF plasmas with non-axisymmetric boundaries. Progress and results from simulations on two experiments will be presented: 1) Detailed validation studies of the HIT-SI experiment with self-consistent modeling of plasma dynamics in the helicity injectors. Results will be compared to experimental data and NIMROD simulations that model the effect of the helicity injectors through boundary conditions on an axisymmetric domain. 2) Linear studies of HBT-EP with different wall configurations focusing on toroidal asymmetries in the adjustable conducting wall. HBT-EP studies the effect of active/passive stabilization with an adjustable ferritic wall. Results from linear verification and benchmark studies of ideal mode growth with and without toroidal asymmetries will be presented and compared to DCON predictions. Simulations of detailed experimental geometries are enabled by use of the PSI-TET code, which employs a high order finite element method on unstructured tetrahedral grids that are generated directly from CAD models. Further development of PSI-TET will also be presented including work to support resistive wall regions within extended MHD simulations. Work supported by DoE.
Cabotegravir long acting injection protects macaques against intravenous challenge with SIVmac251.
Andrews, Chasity D; Bernard, Leslie St; Poon, Amanda Yee; Mohri, Hiroshi; Gettie, Natanya; Spreen, William R; Gettie, Agegnehu; Russell-Lodrigue, Kasi; Blanchard, James; Hong, Zhi; Ho, David D; Markowitz, Martin
2017-02-20
We evaluated the effectiveness of cabotegravir (CAB; GSK1265744 or GSK744) long acting as preexposure prophylaxis (PrEP) against intravenous simian immunodeficiency virus (SIV) challenge in a model that mimics blood transfusions based on the per-act probability of infection. CAB long acting is an integrase strand transfer inhibitor formulated as a 200 mg/ml injectable nanoparticle suspension that is an effective PrEP agent against rectal and vaginal simian/human immunodeficiency virus transmission in macaques. Three groups of rhesus macaques (n = 8 per group) were injected intramuscularly with CAB long acting and challenged intravenously with 17 animal infectious dose 50% SIVmac251 on week 2. Group 1 was injected with 50 mg/kg on week 0 and 4 to evaluate the protective efficacy of the CAB long-acting dose used in macaque studies mimicking sexual transmission. Group 2 was injected with 50 mg/kg on week 0 to evaluate the necessity of the second injection of CAB long acting for protection against intravenous challenge. Group 3 was injected with 25 mg/kg on week 0 and 50 mg/kg on week 4 to correlate CAB plasma concentrations at the time of challenge with protection. Five additional macaques remained untreated as controls. CAB long acting was highly protective with 21 of the 24 CAB long-acting-treated macaques remaining aviremic, resulting in 88% protection. The plasma CAB concentration at the time of virus challenge appeared to be more important for protection than sustaining therapeutic plasma concentrations with the second CAB long acting injection. These results support the clinical investigation of CAB long acting as PrEP in people who inject drugs.
Perrotta, Alberto; Fuentes-Hernandez, Canek; Khan, Talha M.; ...
2016-12-02
Plasma-assisted atomic layer deposition (ALD) is used for the deposition of environmental barriers directly onto organic photovoltaic devices (OPVs) at near room temperature (30 °C). To study the effect of the ALD process on the organic materials forming the device, the precursor diffusion and intermixing at the interface during the growth of different plasma- assisted ALD inorganic barriers (i.e. Al2O3 and TiO2) onto the organic photoactive layer (P3HT:ICBA) was investigated. Depth profile x-ray photoelectron spectroscopy was used to analyze the composition of the organic/inorganic interface to investigate the infiltration of the plasma-assisted ALD precursors into the photoactive layer as amore » function of the precursor dimension, the process temperature, and organic layer morphology. The free volume in the photoactive layer accessible to the ALD precursor was characterized by means of ellipsometric porosimetry (EP) and spectroscopic ellipsometry as a function of temperature. The organic layer is shown to exhibit free volume broadening at high temperatures, increasing the infiltration depth of the ALD precursor into the photoactive layer. Furthermore, based on previous investigations, the intrinsic permeation properties of the inorganic layers deposited by plasma-assisted ALD were predicted from the nano-porosity content as measured by EP and found to be in the 10-6 gm-2 d-1 range. Insight from our studies was used to design and fabricate multilayer barriers synthesized at near-room temperature by plasma-assisted ALD in combination with plasma-enhanced CVD onto organic photovoltaic (OPVs) devices. Encapsulated OPVs displayed shelf-lifetimes up to 1400 h at ambient conditions.« less
Microbial Extracellular Polymeric Substances (EPSs) in Ocean Systems
Decho, Alan W.; Gutierrez, Tony
2017-01-01
Microbial cells (i.e., bacteria, archaea, microeukaryotes) in oceans secrete a diverse array of large molecules, collectively called extracellular polymeric substances (EPSs) or simply exopolymers. These secretions facilitate attachment to surfaces that lead to the formation of structured ‘biofilm’ communities. In open-water environments, they also lead to formation of organic colloids, and larger aggregations of cells, called ‘marine snow.’ Secretion of EPS is now recognized as a fundamental microbial adaptation, occurring under many environmental conditions, and one that influences many ocean processes. This relatively recent realization has revolutionized our understanding of microbial impacts on ocean systems. EPS occur in a range of molecular sizes, conformations and physical/chemical properties, and polysaccharides, proteins, lipids, and even nucleic acids are actively secreted components. Interestingly, however, the physical ultrastructure of how individual EPS interact with each other is poorly understood. Together, the EPS matrix molecules form a three-dimensional architecture from which cells may localize extracellular activities and conduct cooperative/antagonistic interactions that cannot be accomplished efficiently by free-living cells. EPS alter optical signatures of sediments and seawater, and are involved in biogeomineral precipitation and the construction of microbial macrostructures, and horizontal-transfers of genetic information. In the water-column, they contribute to the formation of marine snow, transparent exopolymer particles (TEPs), sea-surface microlayer biofilm, and marine oil snow. Excessive production of EPS occurs during later-stages of phytoplankton blooms as an excess metabolic by product and releases a carbon pool that transitions among dissolved-, colloidal-, and gel-states. Some EPS are highly labile carbon forms, while other forms appear quite refractory to degradation. Emerging studies suggest that EPS contribute to efficient trophic-transfer of environmental contaminants, and may provide a protective refugia for pathogenic cells within marine systems; one that enhances their survival/persistence. Finally, these secretions are prominent in ‘extreme’ environments ranging from sea-ice communities to hypersaline systems to the high-temperatures/pressures of hydrothermal-vent systems. This overview summarizes some of the roles of exopolymer in oceans. PMID:28603518
NASA Astrophysics Data System (ADS)
Barnak, D. H.; Davies, J. R.; Fiksel, G.; Chang, P.-Y.; Zabir, E.; Betti, R.
2018-03-01
Magnetized high energy density physics (HEDP) is a very active and relatively unexplored field that has applications in inertial confinement fusion, astrophysical plasma science, and basic plasma physics. A self-contained device, the Magneto-Inertial Fusion Electrical Discharge System, MIFEDS [G. Fiksel et al., Rev. Sci. Instrum. 86, 016105 (2015)], was developed at the Laboratory for Laser Energetics to conduct magnetized HEDP experiments on both the OMEGA [T. R. Boehly et al., Opt. Commun. 133, 495-506 (1997)] and OMEGA EP [J. H. Kelly et al., J. Phys. IV France 133, 75 (2006) and L. J. Waxer et al., Opt. Photonics News 16, 30 (2005)] laser systems. Extremely high magnetic fields are a necessity for magnetized HEDP, and the need for stronger magnetic fields continues to drive the redevelopment of the MIFEDS device. It is proposed in this paper that a magnetic coil that is inductively coupled rather than directly connecting to the MIFEDS device can increase the overall strength of the magnetic field for HEDP experiments by increasing the efficiency of energy transfer while decreasing the effective magnetized volume. A brief explanation of the energy delivery of the MIFEDS device illustrates the benefit of inductive coupling and is compared to that of direct connection for varying coil size and geometry. A prototype was then constructed to demonstrate a 7-fold increase in energy delivery using inductive coupling.
NASA Astrophysics Data System (ADS)
Tan, Xi; Go, David B.
2018-02-01
When gas discharge and plasma devices shrink to the microscale, the electrode distance in the device approaches the mean free path of electrons and they experience few collisions. As microscale gas discharge and plasma devices become more prevalent, the behavior of discharges at these collisionless and near-collisionless conditions need to be understood. In conditions where the characteristic length d is much greater than the mean free path λ (i.e., macroscopic conditions), electron energy distributions (EEDs) and rate coefficients scale with the reduced electric field E/p. However, when d is comparable with or much lower than λ, this E/p scaling breaks. In this work, particle-in-cell/Monte Carlo collision simulations are used to explore the behavior of the EED and subsequent reaction rate coefficients in microscale field emission-driven Townsend discharges for both an atomic (argon) and a molecular (hydrogen) gas. To understand the behavior, a pseudo-analytical model is developed for the spatially integrated EED and rate coefficients in the collisional to collisionless transition regime based on the weighted sum of a fully collisional, two-temperature Maxwellian EED and the ballistic EED. The theory helps clarify the relative contribution of ballistic electrons in these extreme conditions and can be used to more accurately predict when macroscopic E/p scaling fails at the microscale.
ENERGETIC PARTICLE PRESSURE AT INTERPLANETARY SHOCKS: STEREO-A OBSERVATIONS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lario, D.; Decker, R. B.; Roelof, E. C.
2015-11-10
We study periods of elevated energetic particle intensities observed by STEREO-A when the partial pressure exerted by energetic (≥83 keV) protons (P{sub EP}) is larger than the pressure exerted by the interplanetary magnetic field (P{sub B}). In the majority of cases, these periods are associated with the passage of interplanetary shocks. Periods when P{sub EP} exceeds P{sub B} by more than one order of magnitude are observed in the upstream region of fast interplanetary shocks where depressed magnetic field regions coincide with increases of energetic particle intensities. When solar wind parameters are available, P{sub EP} also exceeds the pressure exertedmore » by the solar wind thermal population (P{sub TH}). Prolonged periods (>12 hr) with both P{sub EP} > P{sub B} and P{sub EP} > P{sub TH} may also occur when energetic particles accelerated by an approaching shock encounter a region well upstream of the shock characterized by low magnetic field magnitude and tenuous solar wind density. Quasi-exponential increases of the sum P{sub SUM} = P{sub B} + P{sub TH} + P{sub EP} are observed in the immediate upstream region of the shocks regardless of individual changes in P{sub EP}, P{sub B}, and P{sub TH}, indicating a coupling between P{sub EP} and the pressure of the background medium characterized by P{sub B} and P{sub TH}. The quasi-exponential increase of P{sub SUM} implies a radial gradient ∂P{sub SUM}/∂r > 0 that is quasi-stationary in the shock frame and results in an outward force applied to the plasma upstream of the shock. This force can be maintained by the mobile energetic particles streaming upstream of the shocks that, in the most intense events, drive electric currents able to generate diamagnetic cavities and depressed solar wind density regions.« less
Hematologic parameters of astrorats flown on SL-3
NASA Technical Reports Server (NTRS)
Lange, R. D.; Andrews, R. B.; Gibson, L. A.; Wright, P.; Dunn, C. D. R.
1985-01-01
Hematologic studies were performed on a group of large and small rats which were sacrificed after flying in life sciences shuttle engineering flight SL-3. The results are presented on flight (F) and control (C) 200 gm rats. The small flight animals demonstrated a significant increase in hematocrits, red blood cell counts, hemoglobins and peripheral blood percentages of neutrophils as well as a decrease in percentage of lymphocytes. Erythropoietin (Ep) determinations were similar for the two groups as were the bone marrow an spleen differential counts. In vitro cultures for erythroid colonies of bone marrow showed that in response to different doses of Ep, in all cases where differnces were statistically significant, the F rats had increased colony counts. The changes in red cell parameters could be caused by a decrease in plasma volume. However, no isotopic studies were possible on this flight and this lack points up the need for such studies to determine the red cell mass and plasma volume.
Froula, D H; Boni, R; Bedzyk, M; Craxton, R S; Ehrne, F; Ivancic, S; Jungquist, R; Shoup, M J; Theobald, W; Weiner, D; Kugland, N L; Rushford, M C
2012-10-01
A 10-ps, 263-nm (4ω) laser is being built to probe plasmas produced on the OMEGA EP [J. H. Kelly, L. J. Waxer, V. Bagnoud, I. A. Begishev, J. Bromage, B. E. Kruschwitz, T. E. Kessler, S. J. Loucks, D. N. Maywar, R. L. McCrory et al., J. Phys. IV France 133, 75-80 (2006)]. A suite of optical diagnostics (schlieren, interferometry, and grid image refractometry) has been designed to diagnose and characterize a wide variety of plasmas. Light scattered by the probe beam is collected by an f/4 catadioptric telescope and a transport system is designed to image with a near-diffraction-limited resolution (~1 - μm full width at half maximum) over a 5-mm field of view to a diagnostic table. The transport system provides a contrast greater than 1 : 10(4) with respect to all wavelengths outside of the 263 ± 2 nm measurement range.
Minnis, Alexandra M.; van der Straten, Ariane; Salee, Parichat; Hendrix, Craig W.
2016-01-01
Despite strong evidence that daily oral pre-exposure prophylaxis (PrEP) reduces HIV risk, effectiveness across studies has varied. Inconsistent adherence constitutes one explanation. Efforts to examine adherence are limited when they rely on self-reported measures. We examined recent adherence as measured by plasma tenofovir (TFV) concentration in participants of MTN-001, a phase 2 cross-over trial comparing oral tablet and vaginal gel formulations of TFV among 144 HIV-uninfected women at sites in the United States (US) and sub-Saharan Africa (SSA). Adherence to daily product use was higher in the US than in the SSA sites. Within region, however, adherence was similar between products. In the US, gel adherence was higher among married women, and lower among women using male condoms and injectable contraceptives. At the SSA sites, gel adherence was lower for younger women. Inconsistent adherence points to challenges in use of daily PrEP, even during a trial of short duration. PMID:25969178
NASA Astrophysics Data System (ADS)
Froula, D. H.; Boni, R.; Bedzyk, M.; Craxton, R. S.; Ehrne, F.; Ivancic, S.; Jungquist, R.; Shoup, M. J.; Theobald, W.; Weiner, D.; Kugland, N. L.; Rushford, M. C.
2012-10-01
A 10-ps, 263-nm (4ω) laser is being built to probe plasmas produced on the OMEGA EP [J. H. Kelly, L. J. Waxer, V. Bagnoud, I. A. Begishev, J. Bromage, B. E. Kruschwitz, T. E. Kessler, S. J. Loucks, D. N. Maywar, R. L. McCrory et al., J. Phys. IV France 133, 75-80 (2006)], 10.1051/jp4:2006133015. A suite of optical diagnostics (schlieren, interferometry, and grid image refractometry) has been designed to diagnose and characterize a wide variety of plasmas. Light scattered by the probe beam is collected by an f/4 catadioptric telescope and a transport system is designed to image with a near-diffraction-limited resolution (˜1 - μm full width at half maximum) over a 5-mm field of view to a diagnostic table. The transport system provides a contrast greater than 1 : 104 with respect to all wavelengths outside of the 263 ± 2 nm measurement range.
Fish, Katherine E; Collins, Richard; Green, Nicola H; Sharpe, Rebecca L; Douterelo, Isabel; Osborn, A Mark; Boxall, Joby B
2015-01-01
Within drinking water distribution systems (DWDS), microorganisms form multi-species biofilms on internal pipe surfaces. A matrix of extracellular polymeric substances (EPS) is produced by the attached community and provides structure and stability for the biofilm. If the EPS adhesive strength deteriorates or is overcome by external shear forces, biofilm is mobilised into the water potentially leading to degradation of water quality. However, little is known about the EPS within DWDS biofilms or how this is influenced by community composition or environmental parameters, because of the complications in obtaining biofilm samples and the difficulties in analysing EPS. Additionally, although biofilms may contain various microbial groups, research commonly focuses solely upon bacteria. This research applies an EPS analysis method based upon fluorescent confocal laser scanning microscopy (CLSM) in combination with digital image analysis (DIA), to concurrently characterize cells and EPS (carbohydrates and proteins) within drinking water biofilms from a full-scale DWDS experimental pipe loop facility with representative hydraulic conditions. Application of the EPS analysis method, alongside DNA fingerprinting of bacterial, archaeal and fungal communities, was demonstrated for biofilms sampled from different positions around the pipeline, after 28 days growth within the DWDS experimental facility. The volume of EPS was 4.9 times greater than that of the cells within biofilms, with carbohydrates present as the dominant component. Additionally, the greatest proportion of EPS was located above that of the cells. Fungi and archaea were established as important components of the biofilm community, although bacteria were more diverse. Moreover, biofilms from different positions were similar with respect to community structure and the quantity, composition and three-dimensional distribution of cells and EPS, indicating that active colonisation of the pipe wall is an important driver in material accumulation within the DWDS.
Fish, Katherine E.; Collins, Richard; Green, Nicola H.; Sharpe, Rebecca L.; Douterelo, Isabel; Osborn, A. Mark; Boxall, Joby B.
2015-01-01
Within drinking water distribution systems (DWDS), microorganisms form multi-species biofilms on internal pipe surfaces. A matrix of extracellular polymeric substances (EPS) is produced by the attached community and provides structure and stability for the biofilm. If the EPS adhesive strength deteriorates or is overcome by external shear forces, biofilm is mobilised into the water potentially leading to degradation of water quality. However, little is known about the EPS within DWDS biofilms or how this is influenced by community composition or environmental parameters, because of the complications in obtaining biofilm samples and the difficulties in analysing EPS. Additionally, although biofilms may contain various microbial groups, research commonly focuses solely upon bacteria. This research applies an EPS analysis method based upon fluorescent confocal laser scanning microscopy (CLSM) in combination with digital image analysis (DIA), to concurrently characterize cells and EPS (carbohydrates and proteins) within drinking water biofilms from a full-scale DWDS experimental pipe loop facility with representative hydraulic conditions. Application of the EPS analysis method, alongside DNA fingerprinting of bacterial, archaeal and fungal communities, was demonstrated for biofilms sampled from different positions around the pipeline, after 28 days growth within the DWDS experimental facility. The volume of EPS was 4.9 times greater than that of the cells within biofilms, with carbohydrates present as the dominant component. Additionally, the greatest proportion of EPS was located above that of the cells. Fungi and archaea were established as important components of the biofilm community, although bacteria were more diverse. Moreover, biofilms from different positions were similar with respect to community structure and the quantity, composition and three-dimensional distribution of cells and EPS, indicating that active colonisation of the pipe wall is an important driver in material accumulation within the DWDS. PMID:25706303
Zhao, Chao; Ruan, Lingwei
2011-11-01
The bacteria involved in the biodegradation of Enteromorpha prolifera (EP) are largely unknown, especially in offshore mangrove environments. In order to obtain the bacterial EP-degrading communities, sediments from a typical mangrove forest were sampled on the roots of mangrove in Dongzhai Port (Haikou, China). The sediments were enriched with crude EP powders as the sole carbon source. The bacterial composition of the resulting mangrove-degrading micro-community (MDMC), named D2-1, was analysed. With methods of plate cultivation and polymerase chain reaction-denaturing gradient gel electrophoresis and 16S rRNA library analysis, 18 bacteria belonging to nine genera were detected from this community. Among these detected bacteria, five major bands closely related to Bacillus, Marinobacter, Paenibacillus, Photobacterium, and Zhouia were determined. A novel two-step pretreatment for EP was proposed to lower the severity requirement of biodegraded pretreatment time. It consisted of a mild physical or chemical step (ultrasonic or H(2)O(2)) and a subsequent biological treatment with community D2-1. The combined treatment led to significant increases in the EP degradation. After combined treatment, the net yields of total soluble sugars and reducing sugars increased. The combined pretreatment of H(2)O(2) (2%, 48 h) and MDMC (7 days) was more effective than the treatment of MDMC only for 15 days. It could remarkably shorten the residence time and reduce the losses of carbohydrates. © Springer-Verlag 2011
Castro, Morgana G; Araújo, Cleudmar A; Menegaz, Gabriela L; Silva, João Paulo L; Nóbilo, Mauro Antônio A; Simamoto Júnior, Paulo Cézar
2015-05-01
The literature provides limited information regarding the performance of Ti-6Al-4V laser and plasma joints welded in prefabricated bars in dental applications. The purpose of this study was to evaluate the mechanical strength of different diameters of Ti-6Al-4V alloy welded with laser and plasma techniques. Forty-five dumbbell-shaped rods were created from Ti-6Al-4V and divided into 9 groups (n=5): a control group with 3-mm and intact bars; groups PL2.5, PL3, PL4, and PL5 (specimens with 2.5-, 3-, 4-, and 5-mm diameters welded with plasma); and groups L2.5, L3, L4, and L5 (specimens with 2.5-, 3-, 4-, and 5-mm diameters welded with laser). The specimens were tested for ultimate tensile strength (UTS), and elongation percentages (EP) were obtained. Fractured specimens were analyzed by stereomicroscopy, and welded area percentages (WAP) were calculated. Images were made with scanning electron microscopy. In the initial analysis, the data were analyzed with a 2-way ANOVA (2×4) and the Tukey Honestly Significant Difference (HSD) test. In the second analysis, the UTS and EP data were analyzed with 1-way ANOVA, and the Dunnett test was used to compare the 4 experimental groups with the control group (α=.05). The Pearson and Spearman correlation coefficient tests were applied to correlate the study factors. Finite element models were developed in a workbench environment with boundary conditions simulating those of a tensile test. The 2-way ANOVA showed that the factors welding type and diameter were significant for the UTS and WAP values. However, the interaction between them was not significant. The 1-way ANOVA showed statistically significant differences among the groups for UTS, WAP, and EP values. The Dunnett test showed that all the tested groups had lower UTS and EP values than the control group. The 2.5- and 3-mm diameter groups showed higher values for UTS and WAP than the other test groups. A positive correlation was found between welded area percentage and UTS and a negative correlation between these parameters and the diameters of the specimens. No statistically significant difference was found between the weld techniques. Under the experimental conditions described, diameters of 2.5 and 3 mm resulted in higher UTS and WAP for both laser and plasma welding and appear to be the best option for joining prefabricated rods in this kind of union. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Yang, Claire C; Miller, Jane L; Omidpanah, Adam; Krieger, John N
2018-06-01
To examine the feasibility of implementing a standardized, clinically relevant genitourinary examination for both men and women, and to identify physical examination findings characteristic of urologic chronic pelvic pain syndrome (UCPPS). This study analyzed 2 samples: men and women with UCPPS who participated in the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network Epidemiology and Phenotyping (EP) Study, and age-matched controls who were either positive for chronic fatigue syndrome or healthy (pain-free). We compared physical examination findings in both positive and healthy controls with UCPPS cases: findings from both the EP examinations and from an extended genitourinary examination. EP and extended examinations were performed on 143 participants: 62 UCPPS cases (30 women, 32 men), 42 positive controls (15 women, 27 men), and 39 healthy controls (22 women, 17 men). EP examinations showed that pelvic floor tenderness was more prevalent in cases (55.0%) than in positive (14.6%) or healthy controls (10.5%). Extended examinations revealed specific areas of tenderness in the pelvic floor musculature. Cases were also more likely than healthy controls to report tenderness in multiple areas, including suprapubic, symphysis pubis, and posterior superior iliac spine, and on bimanual examination. No comparative findings were specific to biological sex, and no evidence of pudendal neuropathy was observed on extended examination of cases or controls. The extended genitourinary examination is an easily administered addition to the assessment of men and women during evaluation for UCPPS. Physical findings may help to better categorize patients with UCPPS into clinically relevant subgroups for optimal treatment. Published by Elsevier Inc.
Huang, Tzu-ting; Yeh, Chieh-Ying; Tsai, Yc-Chen
2011-04-01
to examine the effect of individual counselling on diet and physical activity from pregnancy to six months post partum, or from birth to six months post partum, on weight retention among Taiwanese women. a randomised controlled trial assigned participants to two experimental groups [from pregnancy to six months post partum (EP) and from birth to six months post partum (EPP)] and one comparison group. a 3900-bed medical centre in northern Taiwan with around 3000 births annually. a sample of 189 women who had regular check-ups during pregnancy and gave birth at the medical centre. the comparison group received the routine outpatient department obstetric educational programme. The EP group attended regularly scheduled clinic visits with individualised dietary and physical activity education plans from 16 gestational weeks to six months post partum, and received on brochure. The EPP group received the same educational intervention as the EP group from 24-48 hours after birth to six months post partum. body weight, body mass index, health-promoting behaviour and psycho-social variables (self-efficacy, body image, depression and social support). average gestational weight gain was 14.02, 15.27 and 16.22 kg in the three EP, EPP and comparison groups respectively, and average weight retention at six months post partum was 2.34, 4.06 and 5.08 kg in the three groups, respectively. a diet and physical activity intervention from pregnancy is effective for reducing post-pregnancy weight retention. the findings of the present study should be taken into consideration when incorporating significant others and weight-loss maintenance strategies with interventions for a healthier family lifestyle. Copyright © 2009 Elsevier Ltd. All rights reserved.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Characteristics 830.6302 Color R TGAI TGAI -- 830.6303 Physical state R TGAI TGAI -- 830.6304 Odor R TGAI TGAI... Characteristics R MP EP 5 830.7000 pH R TGAI TGAI -- 830.7100 Viscosity R MP EP 6 830.7300 Density/relative... microbial pesticides are packaged in metal, plastic, or paper containers. 6. Only required for liquid forms...
NASA Astrophysics Data System (ADS)
Fable, E.; Angioni, C.; Ivanov, A. A.; Lackner, K.; Maj, O.; Medvedev, S. Yu; Pautasso, G.; Pereverzev, G. V.; Treutterer, W.; the ASDEX Upgrade Team
2013-07-01
The modelling of tokamak scenarios requires the simultaneous solution of both the time evolution of the plasma kinetic profiles and of the magnetic equilibrium. Their dynamical coupling involves additional complications, which are not present when the two physical problems are solved separately. Difficulties arise in maintaining consistency in the time evolution among quantities which appear in both the transport and the Grad-Shafranov equations, specifically the poloidal and toroidal magnetic fluxes as a function of each other and of the geometry. The required consistency can be obtained by means of iteration cycles, which are performed outside the equilibrium code and which can have different convergence properties depending on the chosen numerical scheme. When these external iterations are performed, the stability of the coupled system becomes a concern. In contrast, if these iterations are not performed, the coupled system is numerically stable, but can become physically inconsistent. By employing a novel scheme (Fable E et al 2012 Nucl. Fusion submitted), which ensures stability and physical consistency among the same quantities that appear in both the transport and magnetic equilibrium equations, a newly developed version of the ASTRA transport code (Pereverzev G V et al 1991 IPP Report 5/42), which is coupled to the SPIDER equilibrium code (Ivanov A A et al 2005 32nd EPS Conf. on Plasma Physics (Tarragona, 27 June-1 July) vol 29C (ECA) P-5.063), in both prescribed- and free-boundary modes is presented here for the first time. The ASTRA-SPIDER coupled system is then applied to the specific study of the modelling of controlled current ramp-up in ASDEX Upgrade discharges.
Dorr, R T; Briggs, A; Kintzel, P; Meyers, R; Chow, H-H S; List, A
2003-04-01
The pharmacokinetics of two etoposide (E) formulations were evaluated in patients with refractory hematologic malignancies receiving high-dose conditioning with autologous stem cell transplantation. Patients were randomized to either E at 800 mg/m(2) (containing polysorbate 80 and polyethylene glycol) or etoposide phosphate (EP) at 910 mg/m(2) on days -7 and -5, prior to melphalan, 80 mg/m(2) on day -5. On day -3, EP was repeated. Plasma E was analyzed after each formulation on days -7 and -5 to compare intrapatient pharmacokinetics. In total, 10 patients were treated: four each with multiple myeloma or Hodgkin's disease and two with non-Hodgkin's lymphoma. Mucositis was the major toxicity with seven patients. EP first produced grade 3 mucositis. There was no procedure-related mortality and eight patients remained alive 1 year post-transplant. Cumulative etoposide exposure (AUC) was slightly greater with EP (P=0.056). Conversely, the volume of distribution was slightly, 33%, larger (P=0.052) and clearance was increased with the E infusion (P=0.14). As none of the differences reached statistical significance, both E formulations appear to be pharmacokinetically equivalent in the high-dose transplant setting. The combination of high-dose EP with melphalan is an active preparative regimen prior to ABMT for hematologic malignancies.
Hybridized polymer matrix composites
NASA Technical Reports Server (NTRS)
London, A.
1981-01-01
Design approaches and materials are described from which are fabricated pyrostatic graphite/epoxy (Gr/Ep) laminates that show improved retention of graphite particulates when subjected to burning. Sixteen hybridized plus two standard Gr/Ep laminates were designed, fabricated, and tested in an effort to eliminate the release of carbon (graphite) fiber particles from burned/burning, mechanically disturbed samples. The term pyrostatic is defined as meaning mechanically intact in the presence of fire. Graphite particulate retentive laminates were constructed whose constituent materials, cost of fabrication, and physical and mechanical properties were not significantly different from existing Gr/Ep composites. All but one laminate (a Celion graphite/bis-maleimide polyimide) were based on an off-the-shelf Gr/Ep, the AS-1/3501-5A system. Of the 16 candidates studied, four thin (10-ply) and four thick (50-ply) hybridized composites are recommended.
Evolution of Motor Control: From Reflexes and Motor Programs to the Equilibrium-Point Hypothesis
Latash, Mark L.
2009-01-01
This brief review analyzes the evolution of motor control theories along two lines that emphasize active (motor programs) and reactive (reflexes) features of voluntary movements. It suggests that the only contemporary hypothesis that integrates both approaches in a fruitful way is the equilibrium-point hypothesis. Physical, physiological, and behavioral foundations of the EP-hypothesis are considered as well as relations between the EP-hypothesis and the recent developments of the notion of motor synergies. The paper ends with a brief review of the criticisms of the EP-hypothesis and challenges that the hypothesis faces at this time. PMID:19823595
Impact of Pre-Plasma on Electron Generation and Transport in Laser Plasma Interactions
NASA Astrophysics Data System (ADS)
Peebles, Jonathan Lee
Relativistic laser plasma interactions in conjunction with an underdense pre-plasma have been shown to generate a two temperature component electron spectrum. The lower temperature component described by "ponderomotive scaling'" is relatively well known and understood and is useful for applications such as the fast ignition inertial confinement fusion scheme. The higher energy electrons generated due to pre-plasma are denoted as "super-ponderomotive" electrons and facilitate interesting and useful applications. These include but are not limited to table top particle acceleration and generating high energy protons, x-rays and neutrons from secondary interactions. This dissertation describes experimental and particle-in-cell computational studies of the electron spectra produced from interactions between short pulse high intensity lasers and controlled pre-plasma conditions. Experiments were conducted at 3 laser labs: Texas Petawatt (University of Texas at Austin), Titan (Lawrence Livermore National Laboratory) and OMEGA-EP (University of Rochester). These lasers have different capabilities, and multiple experiments were carried out in order to fully understand super-ponderomotive electron generation and transport in the high intensity laser regime (I > 1018 W/cm2). In these experiments, an additional secondary long pulse beam was used to generate different scale lengths of "injected" pre-plasma while the pulse length and intensity of the short pulse beam were varied. The temperature and quantity of super-ponderomotive electrons were monitored with magnetic spectrometers and inferred via bremsstrahlung spectrometers while trajectory was estimated via Cu-Kalpha imaging. The experimental and simulation data show that super-ponderomotive electrons require pulse lengths of at least 450 fs to be accelerated and that higher intensity interactions generate large magnetic fields which cause severe deflection of the super-ponderomotive electrons. Laser incidence angle is shown to be extremely important in determining hot electron trajectory. Longer pulse length data taken on OMEGA-EP and Titan showed that super-ponderomotive electrons could be created without the need for an initial pre-plasma due to the underdense plasma created during the high intensity interaction alone.
Duwal, Sulav; Dickinson, Laura; Khoo, Saye; von Kleist, Max
2018-06-01
To achieve the 90-90-90 goals set by UNAIDS, the number of new HIV infections needs to decrease to approximately 500,000 by 2020. One of the 'five pillars' to achieve this goal is pre-exposure prophylaxis (PrEP). Truvada (emtricitabine-tenofovir) is currently the only medication approved for PrEP. Despite its advantages, Truvada is costly and requires individuals to adhere to the once-daily regimen. To improve PrEP, many next-generation regimen, including long-acting formulations, are currently investigated. However, pre-clinical testing may not guide candidate selection, since it often fails to translate into clinical efficacy. On the other hand, quantifying prophylactic efficacy in the clinic is ethically problematic and requires to conduct long (years) and large (N>1000 individuals) trials, precluding systematic evaluation of candidates and deployment strategies. To prioritize- and help design PrEP regimen, tools are urgently needed that integrate pharmacological-, viral- and host factors determining prophylactic efficacy. Integrating the aforementioned factors, we developed an efficient and exact stochastic simulation approach to predict prophylactic efficacy, as an example for dolutegravir (DTG). Combining the population pharmacokinetics of DTG with the stochastic framework, we predicted that plasma concentrations of 145.18 and 722.23nM prevent 50- and 90% sexual transmissions respectively. We then predicted the reduction in HIV infection when DTG was used in PrEP, PrEP 'on demand' and post-exposure prophylaxis (PEP) before/after virus exposure. Once daily PrEP with 50mg oral DTG prevented 99-100% infections, and 85% of infections when 50% of dosing events were missed. PrEP 'on demand' prevented 79-84% infections and PEP >80% when initiated within 6 hours after virus exposure and continued for as long as possible. While the simulation framework can easily be adapted to other PrEP candidates, our simulations indicated that oral 50mg DTG is non-inferior to Truvada. Moreover, the predicted 90% preventive concentrations can guide release kinetics of currently developed DTG nano-formulations.
Microinstabilities in the pedestal region
NASA Astrophysics Data System (ADS)
Dickinson, David; Dudson, Benjamin; Wilson, Howard; Roach, Colin
2014-10-01
The regulation of transport at the pedestal top is important for the inter-ELM pedestal dynamics. Linear gyrokinetic analysis of the pedestal region during an ELM cycle on MAST has shown kinetic ballooning modes to be unstable at the knee of the pressure profile and in the steep pedestal region whilst microtearing modes (MTMs) dominate in the shallow gradient region inboard of the pedestal top. The transition between these instabilities at the pedestal knee has been observed in low and high collisionality MAST pedestals, and is likely to play an important role in the broadening of the pedestal. Nonlinear simulations are needed in this region to understand the microturbulence, the corresponding transport fluxes, and to gain further insight into the processes underlying the pedestal evolution. Such gyrokinetic simulations are numerically challenging and recent upgrades to the GS2 gyrokinetic code help improve their feasibility. We are also exploring reduced models that capture the relevant physics using the plasma simulation framework BOUT + + . An electromagnetic gyrofluid model has recently been implemented with BOUT + + that has significantly reduced computational cost compared to the gyrokinetic simulations against which it will be benchmarked. This work was funded by the RCUK Energy programme, EURATOM and a EUROFusion fellowship WP14-FRF-CCFE/Dickinson and was carried out using: HELIOS at IFERC, Japan; ARCHER (EPSRC Grant No. EP/L000237/1); HECToR (EPSRC Grant No. EP/H002081/1).
Li, Zhiwei; Ai, Tao; Hu, Yiqi; Yan, Xu; Nickel, Marcel Dominik; Xu, Xiao; Xia, Liming
2018-01-01
To investigate the application of whole-lesion histogram analysis of pharmacokinetic parameters for differentiating malignant from benign breast lesions on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). In all, 92 women with 97 breast lesions (26 benign and 71 malignant lesions) were enrolled in this study. Patients underwent dynamic breast MRI at 3T using a prototypical CAIPIRINHA-Dixon-TWIST-VIBE (CDT-VIBE) sequence and a subsequent surgery or biopsy. Inflow rate of the agent between plasma and interstitium (K trans ), outflow rate of agent between interstitium and plasma (K ep ), extravascular space volume per unit volume of tissue (v e ) including mean value, 25th/50th/75th/90th percentiles, skewness, and kurtosis were then calculated based on the whole lesion. A single-sample Kolmogorov-Smirnov test, paired t-test, and receiver operating characteristic curve (ROC) analysis were used for statistical analysis. Malignant breast lesions had significantly higher K trans , K ep , and lower v e in mean values, 25th/50th/75th/90th percentiles, and significantly higher skewness of v e than benign breast lesions (all P < 0.05). There was no significant difference in kurtosis values between malignant and benign breast lesions (all P > 0.05). The 90th percentile of K trans , the 90th percentile of K ep , and the 50th percentile of v e showed the greatest areas under the ROC curve (AUC) for each pharmacokinetic parameter derived from DCE-MRI. The 90th percentile of K ep achieved the highest AUC value (0.927) among all histogram-derived values. The whole-lesion histogram analysis of pharmacokinetic parameters can improve the diagnostic accuracy of breast DCE-MRI with the CDT-VIBE technique. The 90th percentile of K ep may be the best indicator in differentiation between malignant and benign breast lesions. 4 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2018;47:91-96. © 2017 International Society for Magnetic Resonance in Medicine.
Liu, Albert Y; Yang, Qiyun; Huang, Yong; Bacchetti, Peter; Anderson, Peter L; Jin, Chengshi; Goggin, Kathy; Stojanovski, Kristefer; Grant, Robert; Buchbinder, Susan P; Greenblatt, Ruth M; Gandhi, Monica
2014-01-01
Pre-exposure prophylaxis (PrEP) trials using tenofovir-based regimens have demonstrated that high levels of adherence are required to evaluate efficacy; the incorporation of objective biomarkers of adherence in trial design has been essential to interpretation, given the inaccuracy of self-report. Antiretroviral measurements in scalp hair have been useful as a marker of long-term exposure in the HIV treatment setting, and hair samples are relatively easy and inexpensive to collect, transport, and store for analysis. To evaluate the relationship between dose and tenofovir concentrations in hair, we examined the dose proportionality of tenofovir in hair in healthy, HIV-uninfected adults. A phase I, crossover pharmacokinetic study was performed in 24 HIV-negative adults receiving directly-observed oral tenofovir tablets administered 2, 4, and 7 doses/week for 6 weeks, with a ≥3-week break between periods. Small samples of hair were collected after each six-week period and analyzed for tenofovir concentrations. Geometric-mean-ratios compared levels between each pair of dosing conditions. Intensive plasma pharmacokinetic studies were performed during the daily-dosing period to calculate areas-under-the-time-concentration curves (AUCs). Over 90% of doses were observed per protocol. Median tenofovir concentrations in hair increased monotonically with dose. A log-linear relationship was seen between dose and hair levels, with an estimated 76% (95% CI 60-93%) increase in hair level per 2-fold dose increase. Tenofovir plasma AUCs modestly predicted drug concentrations in hair. This study found a strong linear relationship between frequency of dosing and tenofovir levels in scalp hair. The analysis of quantitative drug levels in hair has the potential to improve adherence measurement in the PrEP field and may be helpful in determining exposure thresholds for protection and explaining failures in PrEP trials. Hair measures for adherence monitoring may also facilitate adherence measurement in real-world settings and merit further investigation in upcoming PrEP implementation studies and programs. ClinicalTrials.gov NCT00903084.
Liu, Albert Y.; Yang, Qiyun; Huang, Yong; Bacchetti, Peter; Anderson, Peter L.; Jin, Chengshi; Goggin, Kathy; Stojanovski, Kristefer; Grant, Robert; Buchbinder, Susan P.; Greenblatt, Ruth M.; Gandhi, Monica
2014-01-01
Background Pre-exposure prophylaxis (PrEP) trials using tenofovir-based regimens have demonstrated that high levels of adherence are required to evaluate efficacy; the incorporation of objective biomarkers of adherence in trial design has been essential to interpretation, given the inaccuracy of self-report. Antiretroviral measurements in scalp hair have been useful as a marker of long-term exposure in the HIV treatment setting, and hair samples are relatively easy and inexpensive to collect, transport, and store for analysis. To evaluate the relationship between dose and tenofovir concentrations in hair, we examined the dose proportionality of tenofovir in hair in healthy, HIV-uninfected adults. Methods A phase I, crossover pharmacokinetic study was performed in 24 HIV-negative adults receiving directly-observed oral tenofovir tablets administered 2, 4, and 7 doses/week for 6 weeks, with a ≥3-week break between periods. Small samples of hair were collected after each six-week period and analyzed for tenofovir concentrations. Geometric-mean-ratios compared levels between each pair of dosing conditions. Intensive plasma pharmacokinetic studies were performed during the daily-dosing period to calculate areas-under-the-time-concentration curves (AUCs). Results Over 90% of doses were observed per protocol. Median tenofovir concentrations in hair increased monotonically with dose. A log-linear relationship was seen between dose and hair levels, with an estimated 76% (95% CI 60–93%) increase in hair level per 2-fold dose increase. Tenofovir plasma AUCs modestly predicted drug concentrations in hair. Conclusions This study found a strong linear relationship between frequency of dosing and tenofovir levels in scalp hair. The analysis of quantitative drug levels in hair has the potential to improve adherence measurement in the PrEP field and may be helpful in determining exposure thresholds for protection and explaining failures in PrEP trials. Hair measures for adherence monitoring may also facilitate adherence measurement in real-world settings and merit further investigation in upcoming PrEP implementation studies and programs. Trial Registration ClinicalTrials.gov +NCT00903084. PMID:24421901
NASA Astrophysics Data System (ADS)
Carmona, A. M.; Poveda, G.; Sivapalan, M.; Vallejo-Bernal, S. M.; Bustamante, E.
2016-02-01
This paper studies a 3-D state space representation of Budyko's framework designed to capture the mutual interdependence among long-term mean actual evapotranspiration (E), potential evapotranspiration (Ep) and precipitation (P). For this purpose we use three dimensionless and dependent quantities: Ψ = E ⁄ P, Φ = Ep ⁄ P and Ω = E ⁄ Ep. This 3-D space and its 2-D projections provide an interesting setting to test the physical soundness of Budyko's hypothesis. We demonstrate analytically that Budyko-type equations are unable to capture the physical limit of the relation between Ω and Φ in humid environments, owing to the unfeasibility of Ep ⁄ P = 0 when E ⁄ Ep → 1. Using data from 146 sub-catchments in the Amazon River basin we overcome this inconsistency by proposing a physically consistent power law: Ψ = kΦe, with k = 0.66, and e = 0.83 (R2 = 0.93). This power law is compared with two other Budyko-type equations. Taking into account the goodness of fits and the ability to comply with the physical limits of the 3-D space, our results show that the power law is better suited to model the coupled water and energy balances within the Amazon River basin. Moreover, k is found to be related to the partitioning of energy via evapotranspiration in terms of Ω. This suggests that our power law implicitly incorporates the complementary relationship of evapotranspiration into the Budyko curve, which is a consequence of the dependent nature of the studied variables within our 3-D space. This scaling approach is also consistent with the asymmetrical nature of the complementary relationship of evapotranspiration. Looking for a physical explanation for the parameters k and e, the inter-annual variability of individual catchments is studied. Evidence of space-time symmetry in Amazonia emerges, since both between-catchment and between-year variability follow the same Budyko curves. Finally, signs of co-evolution of catchments are explored by linking spatial patterns of the power law parameters with fundamental characteristics of the Amazon River basin. In general, k and e are found to be related to vegetation, topography and water in soils.
Berry, Jesse L; Kim, Jonathan W; Jennelle, Richard; Astrahan, Melvin
2015-09-01
To describe a new surgical technique for intraoperative placement of Eye Physics (EP) plaques for uveal melanoma using a toric marker. A toric marker is designed for cataract surgery to align the axis of astigmatism; its use was modified in this protocol to mark the axis of suture coordinates as calculated by Plaque Simulator (PS) software. The toric marker can be used to localize suture coordinates, in degrees, during intraoperative plaque placement. Linear marking using the toric marker decreases potential inaccuracies associated with the surgeon estimating 'clock-hours' by dot placement. Use of the toric marker aided surgical placement of EP plaques. The EP planning protocol is now designed to display the suture coordinates either by clock-hours or degrees, per surgeon preference. Future research is necessary to determine whether routine use of the toric marker improves operative efficiency. [Ophthalmic Surg Lasers Imaging Retina. 2015;46:866-870.]. Copyright 2015, SLACK Incorporated.
Molina, Jean-Michel; Charreau, Isabelle; Spire, Bruno; Cotte, Laurent; Chas, Julie; Capitant, Catherine; Tremblay, Cecile; Rojas-Castro, Daniela; Cua, Eric; Pasquet, Armelle; Bernaud, Camille; Pintado, Claire; Delaugerre, Constance; Sagaon-Teyssier, Luis; Mestre, Soizic Le; Chidiac, Christian; Pialoux, Gilles; Ponscarme, Diane; Fonsart, Julien; Thompson, David; Wainberg, Mark A; Doré, Veronique; Meyer, Laurence
2017-09-01
Data for on-demand pre-exposure prophylaxis (PrEP) are scarce. We implemented a cohort study to assess its efficacy, safety, and effect on sexual behaviour. We invited men and transgender women who have sex with men, previously enrolled in the randomised placebo-controlled ANRS IPERGAY trial at seven sites (six in France and one in Canada), to participate in an open-label extension with on-demand tenofovir disoproxil fumarate (300 mg) and emtricitabine (200 mg) to be taken before and after sexual intercourse. We assessed the incidence of HIV and other sexually transmitted infections (STIs), PrEP adherence, safety, and sexual behaviour. Statistical analyses included comparisons of proportions and incidence between the randomised phase of the ANRS IPERGAY trial and the open-label phase, and all participants were included in safety analyses. ANRS IPERGAY is registered with ClinicalTrials.gov, number NCT01473472. Between Nov 4, 2014, and Jan 27, 2015, we enrolled 361 participants. Median follow-up was 18·4 months (IQR 17·7-19·1). One participant who discontinued PrEP acquired HIV infection. HIV incidence was 0·19 per 100 person-years (95% CI 0·01-1·08), compared with 6·60 per 100 person-years (3·60-11·05) in the placebo group of the randomised study, indicating a relative reduction of 97% (95% CI 81-100) in the incidence of HIV with on-demand PrEP. Participants used a median of 18 pills of study drugs per month (IQR 11-25), and at the 6 month visit 240 (71%) of 336 participants had tenofovir detected in plasma. Drug-related gastrointestinal events were reported in 49 participants (14%) but were self-limited. Only four participants (1%) discontinued PrEP, three because of an increase in plasma creatinine. The proportion of participants reporting condomless sex at their last receptive anal intercourse significantly increased from 77% (136 of 176 participants) at baseline to 86% (66 of 77 participants) at 18 months' follow-up (p for trend=0·0004). The incidence of a first bacterial STI during this open-label phase did not change significantly compared with the randomised phase (59·0 vs 49·1 per 100 person-years, respectively; p=0·11). On-demand oral PrEP is highly effective at preventing HIV infection among high-risk men who have sex with men and therefore represents an alternative to daily PrEP, expanding choices for HIV prevention. High rates of STIs resulting from low condom use did not undermine PrEP efficacy, but warrant frequent testing. ANRS (France Recherche Nord and Sud Sida-HIV Hépatites), the Canadian HIV Trials Network, Fonds Pierre Bergé-Sidaction, Gilead Sciences, and the Bill & Melinda Gates Foundation. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Udintsev, V. S.; Ottaviani, M.; Maget, P.; Giruzzi, G.; Ségui, J.-L.; Aniel, T.; Artaud, J. F.; Clairet, F.; Goniche, M.; Hoang, G. T.; Huysmans, G. T. A.; Imbeaux, F.; Joffrin, E.; Mazon, D.; Pecquet, A. L.; Sabot, R.; Sirinelli, A.; Vermare, L.; Tore Supra Team; Krämer-Flecken, A.; Koslowski, H. R.; TEXTOR Team; Donné, A. J. H.; Schüller, F. C.; Domier, C. W.; Luhmann, N. C., Jr.; Mirnov, S. V.
2005-08-01
To shed some light on the development of the fast m/n = 1/1 precursor to the sawtooth crash and its influence on plasma transport properties in the vicinity of the q = 1 surface, series of dedicated experiments have been conducted on the Tore Supra and TEXTOR tokamaks. It has been concluded that, before a crash, the hot core gets displaced with respect to the magnetic axis, drifts outwards by as much as 8-10 cm and may change its shape. Observation of the magnetic reconnection process has been made by means of electron cyclotron emission diagnostics. The heat pulse is seen far outside the inversion radius. The colder plasma develops a magnetic island on the former magnetic axis, after the hot core expulsion. Different kinds of behaviour of the m = 1 precursor before the crash, with respect to the displacement of the hot core and the duration of the oscillating phase, have been observed. An ideal kink model alone cannot be used for explanation; therefore, resistive effects play an important role in the mode development. Possible mechanisms that lead an m = 1 mode to such behaviour, and their links to the change in the central q-profile, are discussed. Results have been discussed in the light of various theoretical models of the sawtooth. This is an extended version of the paper presented at the 31st EPS Conf. on Plasma Physics (London, 28 June-2 July 2004).
Circulating Tumor Cells: A Review of Non-EpCAM-Based Approaches for Cell Enrichment and Isolation.
Gabriel, Marta Tellez; Calleja, Lidia Rodriguez; Chalopin, Antoine; Ory, Benjamin; Heymann, Dominique
2016-04-01
Circulating tumor cells (CTCs) are biomarkers for noninvasively measuring the evolution of tumor genotypes during treatment and disease progression. Recent technical progress has made it possible to detect and characterize CTCs at the single-cell level in blood. Most current methods are based on epithelial cell adhesion molecule (EpCAM) detection, but numerous studies have demonstrated that EpCAM is not a universal marker for CTC detection because it fails to detect both carcinoma cells that undergo epithelial-mesenchymal transition (EMT) and CTCs of mesenchymal origin. Moreover, EpCAM expression has been found in patients with benign diseases. A large proportion of the current studies and reviews about CTCs describe EpCAM-based methods, but there is evidence that not all tumor cells can be detected using this marker. Here we describe the most recent EpCAM-independent methods for enriching, isolating, and characterizing CTCs on the basis of physical and biological characteristics and point out the main advantages and disadvantages of these methods. CTCs offer an opportunity to obtain key biological information required for the development of personalized medicine. However, there is no universal marker of these cells. To strengthen the clinical utility of CTCs, it is important to improve existing technologies and develop new, non-EpCAM-based systems to enrich and isolate CTCs. © 2016 American Association for Clinical Chemistry.
Liu, Jiaen; Zhang, Xiaotong; Schmitter, Sebastian; Van de Moortele, Pierre-Francois; He, Bin
2014-01-01
Purpose To develop high-resolution electrical properties tomography (EPT) methods and investigate a gradient-based EPT (gEPT) approach which aims to reconstruct the electrical properties (EP), including conductivity and permittivity, of an imaged sample from experimentally measured B1 maps with improved boundary reconstruction and robustness against measurement noise. Theory and Methods Using a multi-channel transmit/receive stripline head coil, with acquired B1 maps for each coil element, by assuming negligible Bz component compared to transverse B1 components, a theory describing the relationship between B1 field, EP value and their spatial gradient has been proposed. The final EP images were obtained through spatial integration over the reconstructed EP gradient. Numerical simulation, physical phantom and in vivo human experiments at 7 T have been conducted to evaluate the performance of the proposed methods. Results Reconstruction results were compared with target EP values in both simulations and phantom experiments. Human experimental results were compared with EP values in literature. Satisfactory agreement was observed with improved boundary reconstruction. Importantly, the proposed gEPT method proved to be more robust against noise when compared to previously described non-gradient-based EPT approaches. Conclusion The proposed gEPT approach holds promises to improve EP mapping quality by recovering the boundary information and enhancing robustness against noise. PMID:25213371
2012-01-01
Background Overweight and obesity in children in Mexico was among the countries with the highest prevalence's in the world. Mexico currently has few innovative and comprehensive experiences to help curb the growth of this serious public health problem. Therefore, the aim of this study is to assess the effectiveness of a nutrition and physical activity strategy, called "Nutrition on the Go" ("nutrición en movimiento") in maintaining the BMI values of school children in the State of Mexico. Methods A two-stage cluster trial was carried out. Sixty schools were selected in the State of Mexico, of which 30 were randomly assigned to the intervention group (IG) and 30 to the control group (CG). A total of 1020 fifth grade school children participated. The intervention strategy aimed to decrease the energy content of school breakfasts and include fruits and vegetables, as well as increase physical activity and the consumption of water during the time spent at school. The strategy was implemented over a 6-month period. Results The estimated probability (EP) of obesity between baseline and the final stage for the IG decreased 1% (Initial EP = 11.8%, 95%CI 9.0, 15.2, final EP = 10.8, 95%CI 8.4, 13.) For the CG, the probability increased 0.9% (baseline EP = 10.6%; 95%CI 8.1, 13.7; final EP = 11.5, 95%CI 9.0, 14.6). The interaction between the intervention and the stage is the average odd time corrected treatment effect, which is statistically significant (p = 0.01) (OR = 0.68, 95%CI 0.52, 091). This represents the interaction between intervention and stage, which is highly significant (p = 0.01) (OR = 0.68; 95%CI 0.52, 091). In addition, girls had a protective effect on obesity (OR = 0.56; 95%CI 0.39, 0.80). Conclusions The intervention strategy is effective in maintaining the BMI of school children. PMID:22381137
Global Search Methods for Stellarator Design
NASA Astrophysics Data System (ADS)
Mynick, H. E.; Pomphrey, N.
2001-10-01
We have implemented a new variant Stellopt-DE of the stellarator optimizer Stellopt used by the NCSX team.(A. Reiman, G. Fu, S. Hirshman, D. Monticello, et al., EPS Meeting on Controlled Fusion and Plasma Physics Research, Maastricht, the Netherlands, June 14-18, 1999, (European Physical Society, Petit-Lancy, 1999).) It is based on the ``differential evolution'' (DE) algorithm,(R. Storn, K. Price, U.C. Berkeley Technical Report TR-95-012, ICSI (March, 1995).) a global search method which is far less prone than local algorithms such as the Levenberg-Marquardt method presently used in Stellopt to become trapped in local suboptimal minima of the cost function \\chi. Explorations of stellarator configuration space z to which the DE method has been applied will be presented. Additionally, an accompanying effort to understand the results of this more global exploration has found that a wide range of Quasi-Axisymmetric Stellarators (QAS) previously studied fall into a small number of classes, and we obtain maps of \\chi(z) from which one can see the relative positions of these QAS, and the reasons for the classes into which they fall.
Atomic layer deposition of TiO2 on surface modified nanoporous low-k films.
Levrau, Elisabeth; Devloo-Casier, Kilian; Dendooven, Jolien; Ludwig, Karl F; Verdonck, Patrick; Meersschaut, Johan; Baklanov, Mikhail R; Detavernier, Christophe
2013-10-01
This paper explores the effects of different plasma treatments on low dielectric constant (low-k) materials and the consequences for the growth behavior of atomic layer deposition (ALD) on these modified substrates. An O2 and a He/H2 plasma treatment were performed on SiCOH low-k films to modify their chemical surface groups. Transmission FTIR and water contact angle (WCA) analysis showed that the O2 plasma changed the hydrophobic surface completely into a hydrophilic surface, while the He/H2 plasma changed it only partially. In a next step, in situ X-ray fluorescence (XRF), ellipsometric porosimetry (EP), and Rutherford backscattering spectroscopy (RBS) were used to characterize ALD growth of TiO2 on these substrates. The initial growth of TiO2 was found to be inhibited in the original low-k film containing only Si-CH3 surface groups, while immediate growth was observed in the hydrophilic O2 plasma treated film. The latter film was uniformly filled with TiO2 after 8 ALD cycles, while pore filling was delayed to 17 ALD cycles in the hydrophobic film. For the He/H2 plasma treated film, containing both Si-OH and Si-CH3 groups, the in situ XRF data showed that TiO2 could no longer be deposited in the He/H2 plasma treated film after 8 ALD cycles, while EP measurements revealed a remaining porosity. This can be explained by the faster deposition of TiO2 in the hydrophilic top part of the film than in the hydrophobic bulk which leaves the bulk porous, as confirmed by RBS depth profiling. The outcome of this research is not only of interest for the development of advanced interconnects in ULSI technology, but also demonstrates that ALD combined with RBS analysis is a handy approach to analyze the modifications induced by a plasma treatment on a nanoporous thin film.
Absence of circannual toxicity of parathion to starlings
Rattner, B.A.; Grue, C.E.
1990-01-01
Ambient temperature and season have been observed to influence the toxicity of several environmental pollutants in homeotherms. The circannual toxicity of ethyl parathion (EP) was examined in adult European starlings (Sturnus vulgaris). Groups of birds housed in outdoor pens received oral doses of EP (20-150 mg/kg body weight) in fall, winter, spring and summer (temperature range -3.3 to 36.7?C). The median lethal dosage (LD50), and brain and plasma cholinesterase inhibition, were found to be quite similar among seasons. There was some suggestion that EP may have been more toxic during hot weather (winter versus summer LD50 estimate [95% confidence interval]:160 [114-225] vs. 118 [102-136] mg/kg; P<0.10). In view of previous reports in which ambient temperature extremes and harsh weather have enhanced organophosphorus insecticide toxicity to birds, it is concluded that circannual toxicity studies should include measures of sensitivity (acute oral exposure) and vulnerability (dietary exposure) to better predict responses of free-ranging birds
Extraction of Structural Extracellular Polymeric Substances from Aerobic Granular Sludge
Felz, Simon; Al-Zuhairy, Salah; Aarstad, Olav Andreas; van Loosdrecht, Mark C.M.; Lin, Yue Mei
2016-01-01
To evaluate and develop methodologies for the extraction of gel-forming extracellular polymeric substances (EPS), EPS from aerobic granular sludge (AGS) was extracted using six different methods (centrifugation, sonication, ethylenediaminetetraacetic acid (EDTA), formamide with sodium hydroxide (NaOH), formaldehyde with NaOH and sodium carbonate (Na2CO3) with heat and constant mixing). AGS was collected from a pilot wastewater treatment reactor. The ionic gel-forming property of the extracted EPS of the six different extraction methods was tested with calcium ions (Ca2+). From the six extraction methods used, only the Na2CO3 extraction could solubilize the hydrogel matrix of AGS. The alginate-like extracellular polymers (ALE) recovered with this method formed ionic gel beads with Ca2+. The Ca2+-ALE beads were stable in EDTA, formamide with NaOH and formaldehyde with NaOH, indicating that ALE are one part of the structural polymers in EPS. It is recommended to use an extraction method that combines physical and chemical treatment to solubilize AGS and extract structural EPS. PMID:27768085
Adeeyo, Adeyemi Ojutalayo; Lateef, Agbaje; Gueguim-Kana, Evariste Bosco
2016-01-01
Exopolysaccharide (EPS) production by a strain of Lentinus edodes was studied via the effects of treatments with ultraviolet (UV) irradiation and acridine orange. Furthermore, optimization of EPS production was studied using a genetic algorithm coupled with an artificial neural network in submerged fermentation. Exposure to irradiation and acridine orange resulted in improved EPS production (2.783 and 5.548 g/L, respectively) when compared with the wild strain (1.044 g/L), whereas optimization led to improved productivity (23.21 g/L). The EPS produced by various strains also demonstrated good DPPH scavenging activities of 45.40-88.90%, and also inhibited the growth of Escherichia coli and Klebsiella pneumoniae. This study shows that multistep optimization schemes involving physical-chemical mutation and media optimization can be an attractive strategy for improving the yield of bioactives from medicinal mushrooms. To the best of our knowledge, this report presents the first reference of a multistep approach to optimizing EPS production in L. edodes.
Matthys, Heinrich; Lizogub, Victor G; Funk, Petra; Malek, Fathi A
2010-12-01
Health-related quality of life (HRQL) and patient-reported outcome (PRO) have become important outcome parameters for the evaluation of medical treatment within clinical trials and, furthermore, to evaluate efficiency in clinical practice. We therefore report further exploratory results of an already reported dose-finding study with EPs 7630 tablets, now focussing on HRQL and PRO. A total of 406 adults with acute bronchitis were randomly assigned to one of four parallel treatment groups (placebo, 30 mg, 60 mg or 90 mg EPs 7630 daily). HRQL and PRO were assessed by questionnaires as secondary outcome measures at each study visit or daily in the patient's diary. At day 7, the patient-reported outcome measures were significantly more improved in all the three EPs 7630 groups compared to placebo (EQ-5D and EQ VAS, SF-12: physical score, impact of patient's sickness, duration of activity limitation, patient-reported treatment outcome, satisfaction with treatment). In conclusion, a statistically significant and clinically relevant improvement of HRQL/PRO compared to placebo was shown in all the three EPs 7630 groups.
NASA Astrophysics Data System (ADS)
Hu, S. X.; Michel, D. T.; Edgell, D. H.; Froula, D. H.; Follett, R. K.; Goncharov, V. N.; Myatt, J. F.; Skupsky, S.; Yaakobi, B.
2013-03-01
Direct-drive-ignition designs with plastic CH ablators create plasmas of long density scale lengths (Ln ≥ 500 μm) at the quarter-critical density (Nqc) region of the driving laser. The two-plasmon-decay (TPD) instability can exceed its threshold in such long-scale-length plasmas (LSPs). To investigate the scaling of TPD-induced hot electrons to laser intensity and plasma conditions, a series of planar experiments have been conducted at the Omega Laser Facility with 2-ns square pulses at the maximum laser energies available on OMEGA and OMEGA EP. Radiation-hydrodynamic simulations have been performed for these LSP experiments using the two-dimensional hydrocode draco. The simulated hydrodynamic evolution of such long-scale-length plasmas has been validated with the time-resolved full-aperture backscattering and Thomson-scattering measurements. draco simulations for CH ablator indicate that (1) ignition-relevant long-scale-length plasmas of Ln approaching ˜400 μm have been created; (2) the density scale length at Nqc scales as Ln(μm)≃(RDPP×I1/4/2); and (3) the electron temperature Te at Nqc scales as Te(keV)≃0.95×√I , with the incident intensity (I) measured in 1014 W/cm2 for plasmas created on both OMEGA and OMEGA EP configurations with different-sized (RDPP) distributed phase plates. These intensity scalings are in good agreement with the self-similar model predictions. The measured conversion fraction of laser energy into hot electrons fhot is found to have a similar behavior for both configurations: a rapid growth [fhot≃fc×(Gc/4)6 for Gc < 4] followed by a saturation of the form, fhot≃fc×(Gc/4)1.2 for Gc ≥ 4, with the common wave gain is defined as Gc=3 × 10-2×IqcLnλ0/Te, where the laser intensity contributing to common-wave gain Iqc, Ln, Te at Nqc, and the laser wavelength λ0 are, respectively, measured in [1014 W/cm2], [μm], [keV], and [μm]. The saturation level fc is observed to be fc ≃ 10-2 at around Gc ≃ 4. The hot-electron temperature scales roughly linear with Gc. Furthermore, to mitigate TPD instability in long-scale-length plasmas, different ablator materials such as saran and aluminum have been investigated on OMEGA EP. Hot-electron generation has been reduced by a factor of 3-10 for saran and aluminum plasmas, compared to the CH case at the same incident laser intensity. draco simulations suggest that saran might be a better ablator for direct-drive-ignition designs as it balances TPD mitigation with an acceptable hydro-efficiency.
Contributions to Integral Nuclear Data in ICSBEP and IRPhEP since ND 2013
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bess, John D.; Briggs, J. Blair; Gulliford, Jim
2016-09-01
The status of the International Criticality Safety Benchmark Evaluation Project (ICSBEP) and the International Reactor Physics Experiment Evaluation Project (IRPhEP) was last discussed directly with the international nuclear data community at ND2013. Since ND2013, integral benchmark data that are available for nuclear data testing has continued to increase. The status of the international benchmark efforts and the latest contributions to integral nuclear data for testing is discussed. Select benchmark configurations that have been added to the ICSBEP and IRPhEP Handbooks since ND2013 are highlighted. The 2015 edition of the ICSBEP Handbook now contains 567 evaluations with benchmark specifications for 4,874more » critical, near-critical, or subcritical configurations, 31 criticality alarm placement/shielding configuration with multiple dose points apiece, and 207 configurations that have been categorized as fundamental physics measurements that are relevant to criticality safety applications. The 2015 edition of the IRPhEP Handbook contains data from 143 different experimental series that were performed at 50 different nuclear facilities. Currently 139 of the 143 evaluations are published as approved benchmarks with the remaining four evaluations published in draft format only. Measurements found in the IRPhEP Handbook include criticality, buckling and extrapolation length, spectral characteristics, reactivity effects, reactivity coefficients, kinetics, reaction-rate distributions, power distributions, isotopic compositions, and/or other miscellaneous types of measurements for various types of reactor systems. Annual technical review meetings for both projects were held in April 2016; additional approved benchmark evaluations will be included in the 2016 editions of these handbooks.« less
NASA Astrophysics Data System (ADS)
Hope, J. A.; Aspden, R.; Schindler, R.; Parsons, D. R.; Ye, L.; Baas, J.; Paterson, D. M.
2014-12-01
The stability and morphology of bedforms have traditionally been treated as a function of mean flow velocity/non-dimensional bed shear stress and sediment particle size, despite the known influence of key biological components such as extracellular polymeric substances (EPS). EPS is produced by microbial communities and can increase erosion thresholds by more than 300%. However, the mechanisms behind the influence of EPS on sediment transport and bedform dynamics is poorly understood, as is the fate of EPS and exchange of EPS between the sediment bed and water column during ripple formation. The exchange of EPS between the sediment bed and water column is dynamic, with important implications for a range of physical and geochemical processes, with the spatio-temporal variation in EPS content, from source to eventual fate, being extremely important for determining the behaviour and natural variability of sedimentary systems. This paper reports on a series of flume experiments where a tripartite mixture of sand, clay and model EPS (xanthan gum) was used to create a sediment substrate, which was subject to a unidirectional current (0.8 ms-1 for 10.5 hrs, n=6). For each run the spatio-temporal changes in concentration, distribution, and effect of EPS, on the evolving bed of mixed sediment was monitored throughout, with complete 3D bed morphology scans also acquired at ~360 s intervals. The various substrate mixtures produced bedforms varying from ripples to dunes and biochemical analysis of EPS concentration across the formed bedforms, suggest EPS is winnowed from the sediment - water interface, particularly at the bedform crests. The depth of winnowing in each run was found to be related to the bedform size, with variation in the stoss, crest and trough of the bedforms identified. The loss of EPS was also significantly correlated with the depth to which clay was winnowed, presumably due to a close association between the clay mineral and EPS fractions. The paper will discuss how sediment processes and flow are linked by migration of dissolved and particulate substances into and out of the bed and how this exchange is affected by the topography of the sediment bed and advective pore water transfers. Finally, the implications for natural systems and larger scale sediment-biota linkages will also be discussed.
NASA Astrophysics Data System (ADS)
Torki, Mehran; Akbari, Mohsen; Kaviani, Keyomars
2015-09-01
This study was conducted to evaluate the effects of adding zinc (Zn), cinnamon essential oil (Ci), or their combination in diet on productive performance, egg quality, and blood parameters of laying hens reared under cold stress condition (8.8 ± 3 °C). Feed intake (FI), feed conversion ratio (FCR), egg weight (EW), egg production (EP), and egg mass (EM) were evaluated during the 56-day trial period using 120 Lohmann LSL-Lite laying hens. Significant interactions between Ci and Zn on FCR, EW, EP, or EM were observed ( P < 0.05). The EP, EM, and EW increased, whereas FCR decreased ( P < 0.05) in the hens fed the diets including Ci and Zn (as single or combined form) compared to those fed the basal diet. There were significant interactions between Ci and Zn on the serum level of glucose and triglycerides as well as plasma concentration of zinc ( P < 0.05), so that serum content of glucose and triglyceride decreased and the plasma content of zinc increased in the hens fed the diets including Ci and Zn (together) compared to those fed the basal diet. From the results of the present experiment, it can be concluded that diet supplementation by the combined form of Ci and Zn could have beneficial effects on performance and blood parameters of hens reared under cold stress condition.
Relative and absolute reliability of measures of linoleic acid-derived oxylipins in human plasma.
Gouveia-Figueira, Sandra; Bosson, Jenny A; Unosson, Jon; Behndig, Annelie F; Nording, Malin L; Fowler, Christopher J
2015-09-01
Modern analytical techniques allow for the measurement of oxylipins derived from linoleic acid in biological samples. Most validatory work has concerned extraction techniques, repeated analysis of aliquots from the same biological sample, and the influence of external factors such as diet and heparin treatment upon their levels, whereas less is known about the relative and absolute reliability of measurements undertaken on different days. A cohort of nineteen healthy males were used, where samples were taken at the same time of day on two occasions, at least 7 days apart. Relative reliability was assessed using Lin's concordance correlation coefficients (CCC) and intraclass correlation coefficients (ICC). Absolute reliability was assessed by Bland-Altman analyses. Nine linoleic acid oxylipins were investigated. ICC and CCC values ranged from acceptable (0.56 [13-HODE]) to poor (near zero [9(10)- and 12(13)-EpOME]). Bland-Altman limits of agreement were in general quite wide, ranging from ±0.5 (12,13-DiHOME) to ±2 (9(10)-EpOME; log10 scale). It is concluded that relative reliability of linoleic acid-derived oxylipins varies between lipids with compounds such as the HODEs showing better relative reliability than compounds such as the EpOMEs. These differences should be kept in mind when designing and interpreting experiments correlating plasma levels of these lipids with factors such as age, body mass index, rating scales etc. Copyright © 2015 Elsevier Inc. All rights reserved.
Torki, Mehran; Akbari, Mohsen; Kaviani, Keyomars
2015-09-01
This study was conducted to evaluate the effects of adding zinc (Zn), cinnamon essential oil (Ci), or their combination in diet on productive performance, egg quality, and blood parameters of laying hens reared under cold stress condition (8.8 ± 3 °C). Feed intake (FI), feed conversion ratio (FCR), egg weight (EW), egg production (EP), and egg mass (EM) were evaluated during the 56-day trial period using 120 Lohmann LSL-Lite laying hens. Significant interactions between Ci and Zn on FCR, EW, EP, or EM were observed (P < 0.05). The EP, EM, and EW increased, whereas FCR decreased (P < 0.05) in the hens fed the diets including Ci and Zn (as single or combined form) compared to those fed the basal diet. There were significant interactions between Ci and Zn on the serum level of glucose and triglycerides as well as plasma concentration of zinc (P < 0.05), so that serum content of glucose and triglyceride decreased and the plasma content of zinc increased in the hens fed the diets including Ci and Zn (together) compared to those fed the basal diet. From the results of the present experiment, it can be concluded that diet supplementation by the combined form of Ci and Zn could have beneficial effects on performance and blood parameters of hens reared under cold stress condition.
Present and future medical applications of microbial exopolysaccharides
Moscovici, Misu
2015-01-01
Microbial exopolysaccharides (EPS) have found outstanding medical applications since the mid-20th century, with the first clinical trials on dextran solutions as plasma expanders. Other EPS entered medicine firstly as conventional pharmaceutical excipients (e.g., xanthan – as suspension stabilizer, or pullulan – in capsules and oral care products). Polysaccharides, initially obtained from plant or animal sources, became easily available for a wide range of applications, especially when they were commercially produced by microbial fermentation. Alginates are used as anti-reflux, dental impressions, or as matrix for tablets. Hyaluronic acid and derivatives are used in surgery, arthritis treatment, or wound healing. Bacterial cellulose is applied in wound dressings or scaffolds for tissue engineering. The development of drug controlled-release systems and of micro- and nanoparticulated ones, has opened a new era of medical applications for biopolymers. EPS and their derivatives are well-suited potentially non-toxic, biodegradable drug carriers. Such systems concern rating and targeting of controlled release. Their large area of applications is explained by the available manifold series of derivatives, whose useful properties can be thereby controlled. From matrix inclusion to conjugates, different systems have been designed to solubilize, and to assure stable transport in the body, target accumulation and variable rate-release of a drug substance. From controlled drug delivery, EPS potential applications expanded to vaccine adjuvants and diagnostic imaging systems. Other potential applications are related to the bioactive (immunomodulator, antitumor, antiviral) characteristics of EPS. The numerous potential applications still wait to be developed into commercial pharmaceuticals and medical devices. Based on previous and recent results in important medical-pharmaceutical domains, one can undoubtedly state that EPS medical applications have a broad future ahead. PMID:26483763
Tillet, Solenne; Giraud, Sébastien; Kerforne, Thomas; Saint-Yves, Thibaut; Joffrion, Sandrine; Goujon, Jean-Michel; Cau, Jerôme; Mauco, Gérard; Petitou, Maurice; Hauet, Thierry
2016-12-01
Coagulation is an important pathway in the pathophysiology of ischemia-reperfusion injuries. In particular, deceased after circulatory death (DCD) donors undergo a no-flow period, a strong activator of coagulation. Hence, therapies influencing the coagulation cascade must be developed. We evaluated the effect of a new highly specific and effective anti-Xa/IIa molecule, with an integrated innovative antidote site (EP217609), in a porcine preclinical model mimicking injuries observed in DCD donor kidney transplantation. Kidneys were clamped for 60 minutes (warm ischemia), then flushed and preserved for 24 hours at 4°C in University of Wisconsin (UW) solution (supplemented or not). EP217609-supplemented UW solution (UW-EP), compared with unfractionated heparin-supplemented UW solution (UW-UFH) or UW alone (UW). A mechanistic investigation was conducted in vitro: addition of EP217609 to endothelial cells during hypoxia at 4°C in the UW solution inhibited thrombin generation during reoxygenation at 37°C in human plasma and reduced tumor necrosis factor alpha, intercellular adhesion molecule 1, and vascular cell adhesion molecule 1 messenger RNA cell expressions. In vivo, function recovery was markedly improved in the UW-EP group. Interestingly, levels of thrombin-antithrombin complexes (reflecting thrombin generation) were reduced 60 minutes after reperfusion in the UW-EP group. In addition, 3 months after transplantation, lower fibrosis, epithelial-mesenchymal transition, inflammation, and leukocyte infiltration were observed. Using this new dual anticoagulant, anti-Xa/IIa activity during kidney flush and preservation is protected by reducing thrombin generation at revascularization, improving early function recovery, and decreasing chronic lesions. Such an easy-to-deploy clinical strategy could improve marginal graft outcome. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Rapoport, B. I.; Pavlenko, I.; Weyssow, B.; Carati, D.
2002-11-01
Recent studies of ion and electron transport indicate that the safety factor profile, q(r), affects internal transport barrier (ITB) formation in magnetic confinement devices [1, 2]. These studies are consistent with experimental observations that low shear suppresses magnetic island interaction and associated stochasticity when the ITB is formed [3]. In this sense the position and quality of the ITB depend on the stochasticity of the magnetic field, and can be controlled by q(r). This study explores effects of the q-profile on magnetic field stochasticity using two-dimensional mapping techniques. Q-profiles typical of ITB experiments are incorporated into Hamiltonian maps to investigate the relation between magnetic field stochasticity and ITB parameters predicted by other models. It is shown that the mapping technique generates results consistent with these predictions, and suggested that Hamiltonian mappings can be useful as simple and computationally inexpensive approximation methods for describing the magnetic field in ITB experiments. 1. I. Voitsekhovitch et al. 29th EPS Conference on Plasma Physics and Controlled Fusion (2002). O-4.04. 2. G.M.D. Hogeweij et al. Nucl. Fusion. 38 (1998): 1881. 3. K.A. Razumova et al. Plasma Phys. Contr. Fusion. 42 (2000): 973.
Sy, S Kenneth; Sweeney, Theresa D; Ji, Chunmei; Hoch, Ute; Eldon, Michael A
2017-01-01
The relationship between incidences of neutropenia and 10-hydroxy-7-ethyl camptothecin (SN38) exposure was explored using SN38 pharmacokinetic and neutrophil count data from toxicology studies of etirinotecan pegol (EP) and irinotecan in beagle dogs. Dogs received four weekly intravenous infusions of either vehicle control (n = 22), EP (6, 15, 20, 25, 40/25 mg/kg; n = 3-9 dogs/dose group/sex; n = 48), or irinotecan (20 or 25 mg/kg n = 3-4 dogs/dose group/sex; n = 14). Blood samples were collected up to 50 days post-dose for characterization of SN38 pharmacokinetics. Two separate models were created describing SN38 concentration time profiles after either irinotecan or EP administrations to project the AUC 0-168h after Day 1 and Day 22 doses. The relationship between incidence of neutropenia and SN38 exposure was explored using logistic regression. The incidence of neutropenia in dogs receiving weekly doses of irinotecan or EP was strongly correlated with maximum plasma SN38 concentration (C max ), but not SN38 area under the concentration-time curve (AUC). Neutropenia occurred in approximately 80% of dogs receiving irinotecan (mean SN38 C max of 13.5 and 26.3 ng/mL for 20 and 25 mg/kg, respectively). No neutropenia occurred in dogs receiving EP at doses up to and including 25 mg/kg (mean SN38 C max of 3.4 and 4.9 ng/mL for 20 and 25 mg/kg, respectively), despite 2.5-3.6 times greater SN38 AUC after EP compared to irinotecan at equivalent doses. EP administration avoids both high SN38 C max values and development of dose-limiting neutropenia observed after irinotecan, while maintaining greater and sustained SN38 exposure between doses.
Borucki Castro, S I; Lapierre, H; Phillip, L E; Jardon, P W; Berthiaume, R
2008-02-01
Lysine (Lys) availability in three different soya-bean meal (SBM) products was determined using the following techniques: whole body (WB) net flux of Lys, digestible Lys (duodenal flow × intestinal digestibility) and the plasma Lys response curve method of Rulquin and Kowalczyk (2003). Four multiparous Holstein cows (173 days in milk) were equipped with ruminal and duodenal cannulas and used in a 4 × 4 Latin square experiment with 14-day periods. The animals were fed either solvent-extracted SBM (SE), expeller-processed SBM (EP) or lignosulphonate-treated SBM (LS) at 23% of the diet dry matter (DM). The fourth treatment (SE70) consisted of a continuous infusion of Lys (70 g/day) into the omasum of cows fed the SE diet. Chromium(III) oxide was included as a digesta marker in order to determine the duodenal flow of amino acids (AA). On day 12 of each experimental period, six blood samples were collected to determine plasma Lys concentrations. Immediately after that, a pulse dose of L-[2-15N] Lys was administered in the jugular vein. Jugular blood samples were then collected at 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 13, 16, 19, 25 and 31 min after the injection to determine 15N Lys enrichment. On each of days 13 and 14, eight digesta samples were collected and pooled by period. Amongst the diets of SBM (SE, EP, LS), no differences were observed for duodenal Lys flow or digestible Lys. Duodenal flow of microbial N with SE was numerically higher, compared with EP and LS, indicating enhanced duodenal supply of microbial Lys for this diet, and this may have compensated for the additional Lys derived from undegradable protein in rumen-protected SBM products (EP and LS). The use of the plasma response curve method as well as the measurement of WB Lys flux also revealed no differences in Lys availability among the SBM products. The WB flux method resulted in 100% post-ruminal recovery of the Lys infused with diet SE70 compared with the control diet SE, which indicates that the method is reliable for determining Lys availability. The Lys flux approach not only allows for the estimation of intestinally available essential AA but also it avoids the use of cannulated animals.
Channel optimization of high-intensity laser beams in millimeter-scale plasmas
Ceurvorst, L.; Savin, A.; Ratan, N.; ...
2018-04-20
Channeling experiments were performed at the OMEGA EP facility using relativistic intensity (> 10 18 W/cm 2) kilojoule laser pulses through large density scale length (~ 390-570 μm) laser-produced plasmas, demonstrating the effects of the pulse’s focal location and intensity as well as the plasma’s temperature on the resulting channel formation. The results show deeper channeling when focused into hot plasmas and at lower densities as expected. However, contrary to previous large scale particle-in-cell studies, the results also indicate deeper penetration by short (10 ps), intense pulses compared to their longer duration equivalents. To conclude, this new observation has manymore » implications for future laser-plasma research in the relativistic regime.« less
Channel optimization of high-intensity laser beams in millimeter-scale plasmas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ceurvorst, L.; Savin, A.; Ratan, N.
Channeling experiments were performed at the OMEGA EP facility using relativistic intensity (> 10 18 W/cm 2) kilojoule laser pulses through large density scale length (~ 390-570 μm) laser-produced plasmas, demonstrating the effects of the pulse’s focal location and intensity as well as the plasma’s temperature on the resulting channel formation. The results show deeper channeling when focused into hot plasmas and at lower densities as expected. However, contrary to previous large scale particle-in-cell studies, the results also indicate deeper penetration by short (10 ps), intense pulses compared to their longer duration equivalents. To conclude, this new observation has manymore » implications for future laser-plasma research in the relativistic regime.« less
PR^2EPS: Preparation, Recruitment, Retention and Excellence in the Physical Sciences.
NASA Astrophysics Data System (ADS)
Labroo, Sunil; Schaumloffel, John; Gallagher, Hugh; Bischoff, Paul; Bachman, Nancy
2007-03-01
The PR^2EPS program is a multidisciplinary effort to increase the number of majors attending (and graduating) from SUNY Oneonta with degrees in chemistry, physics, biochemistry, astronomy, secondary chemistry or physics education and related areas. Components of the program include a walk-in tutoring center, a free, weeklong summer science camp, scholarship opportunities and an equipment loan program for regional secondary science teachers. 2006 was the third year of this NSF-DUE funded program. Evaluation of our progress to date shows that the program is effective at steering students (or at least reinforcing their desire) to studying the sciences in college. A summary of our goals, challenges and accomplishments, including tutoring center operation and efficacy, activities and operational details for the summer camp and other facets of the program will be presented.
Thill, Marc; Fischer, Dorothea; Hoellen, Friederike; Kelling, Katharina; Dittmer, Christine; Landt, Solveig; Salehin, Darius; Diedrich, Klaus; Friedrich, Michael; Becker, Steffi
2010-05-01
Breast cancer is associated with inflammatory processes based on an up-regulation of cyclooxygenase-2 (COX-2) expression. The antiproliferative effects of calcitriol (1,25(OH)(2)D(3)) mediated via the vitamin D receptor (VDR) render vitamin D a promising target in breast cancer therapy. First data suggest a correlation between vitamin D and prostaglandin metabolism. We determined the expression of VDR, COX-2, 15-PGDH and the prostaglandin receptors EP(2)/EP(4) in normal and malignant breast tissue by real-time PCR and Western blot analysis, as well as 25(OH)(2)D(3) and PGE(2) plasma levels from healthy and breast cancer patients. Significantly higher COX-2, lower VDR and lower EP(2) and EP(4) receptor protein levels in the malignant tissue and a significantly lower 15-PGDH protein level in normal breast tissue were detected. Breast cancer patients older than 45 years, diagnosed and sampled in the winter time had significantly lower 25(OH)(2)D(3) and higher PGE(2) serum levels. The inverse correlation between VDR and both COX-2 and 15-PGDH, as well as between PGE(2) and 25(OH)(2)D(3) levels, suggests a possible link between VDR-associated target genes and prostaglandin metabolism.
Gao, Xiang; Ndongo, Marie-Noella; Checchio, Tina M; Cook, Jack; Duncan, Barbara; LaBadie, Robert R
2015-01-01
The relative bioavailability and bioequivalence of 20-mg doses of a pediatric formulation of sildenafil extemporaneous preparation suspension (EP; 10 mg/mL), the sildenafil 20-mg intact tablet and the crushed sildenafil 20-mg tablet mixed with apple sauce were assessed in a single-dose, randomized, open-label, 3-way crossover study with 18 healthy adult volunteers. Blood samples were collected at predefined times and analyzed for sildenafil plasma concentrations. Natural log-transformed sildenafil pharmacokinetic parameters (Cmax , AUClast , and AUCinf ) were used to estimate relative bioavailability and construct 90% confidence intervals (CI) using a mixed-effects model. Bioequivalence was concluded among the three formulations with one exception, in which the EP suspension showed a 15% decrease in Cmax with a lower 90% CI of 76% compared with the intact tablet. The 15% decrease in sildenafil Cmax is not considered to be clinically relevant. Therefore, the EP suspension is considered to be an appropriate pediatric formulation. All 3 formulations were well tolerated in healthy adult volunteers. © 2014, The American College of Clinical Pharmacology.
NASA Astrophysics Data System (ADS)
Hinton, Courtney; Punjabi, Alkesh; Ali, Halima
2008-11-01
The simple map is the simplest map that has topology of divertor tokamaks [1]. Recently, the action-angle coordinates for simple map are analytically calculated, and simple map is constructed in action-angle coordinates [2]. Action-angle coordinates for simple map can not be inverted to real space coordinates (R,Z). Because there is logarithmic singularity on the ideal separatrix, trajectories can not cross separatrix [2]. Simple map in action-angle coordinates is applied to calculate stochastic broadening due to magnetic noise and field errors. Mode numbers for noise + field errors from the DIII-D tokamak are used. Mode numbers are (m,n)=(3,1), (4,1), (6,2), (7,2), (8,2), (9,3), (10,3), (11,3), (12,3) [3]. The common amplitude δ is varied from 0.8X10-5 to 2.0X10-5. For this noise and field errors, the width of stochastic layer in simple map is calculated. This work is supported by US Department of Energy grants DE-FG02-07ER54937, DE-FG02-01ER54624 and DE-FG02-04ER54793 1. A. Punjabi, H. Ali, T. Evans, and A. Boozer, Phys. Let. A 364, 140--145 (2007). 2. O. Kerwin, A. Punjabi, and H. Ali, to appear in Physics of Plasmas. 3. A. Punjabi and H. Ali, P1.012, 35^th EPS Conference on Plasma Physics, June 9-13, 2008, Hersonissos, Crete, Greece.
European Scientific Notes. Volume 35, Number 3,
1981-03-31
the distribution of par- fodder to feed the animals. ticulate matter in Icelandic coastal Because of their country’s small size waters. He is studying...however, has the possibil- of the Condensed Matter Division of the ity of depositing the energy required for European Physical Society (EPS) which... Matter Division of the heat energy is deposited at the front of EPS. the slab; isothermal (t ’, 10 s), in which Of xital concern to those present the
Kurokawa, Satoshi; Umemoto, Yukihiro; Mizuno, Kentaro; Okada, Atsushi; Nakane, Akihiro; Nishio, Hidenori; Hamamoto, Shuzo; Ando, Ryosuke; Kawai, Noriyasu; Tozawa, Keiichi; Hayashi, Yutaro; Yasui, Takahiro
2017-11-21
Robot-assisted radical prostatectomy (RARP) is commonly performed using the transperitoneal (TP) approach with six trocars over an 8-cm distance in the steep Trendelenburg position. In this study, we investigated the feasibility and the benefit of using the extraperitoneal (EP) approach with six trocars over a 4-cm distance in a flat or 5° Trendelenburg position. We also introduced four new steps to the surgical procedure and compared the surgical results and complications between the EP and TP approach using propensity score matching. Between August 2012 and August 2016, 200 consecutive patients without any physical restrictions underwent RARP with the EP approach in a less than 5° Trendelenburg position, and 428 consecutive patients underwent RARP with the TP approach in a steep Trendelenburg position. Four new steps to RARP using the EP approach were developed: 1) arranging six trocars; 2) creating the EP space using laparoscopic forceps; 3) holding the separated prostate in the EP space outside the robotic view; and 4) preventing a postoperative inguinal hernia. Clinicopathological results and complications were compared between the EP and TP approaches using propensity score matching. Propensity scores were calculated for each patient using multivariate logistic regression based on the preoperative covariates. All 200 patients safely underwent RARP using the EP approach. The mean volume of estimated blood loss and duration of indwelling urethral catheter use were significantly lower with the EP approach than the TP approach (139.9 vs 184.9 mL, p = 0.03 and 5.6 vs 7.7 days, p < 0.01, respectively). No significant differences in the positive surgical margin were observed. None of the patients developed an inguinal hernia postoperatively after we introduced this technique. The EP approach to RARP was safely performed regardless of patient physique or contraindications to a steep Trendelenburg position. Our method, which involved using the EP approach to perform RARP, can decrease the amount of perioperative blood loss, the duration of indwelling urethral catheter use, and the incidence of postoperative inguinal hernia development.
Academic emergency physicians' experiences with patient death.
Strote, Jared; Schroeder, Erika; Lemos, John; Paganelli, Ryan; Solberg, Jonathan; Range Hutson, H
2011-03-01
There is a growing awareness of the effects of patient death on physician well-being, and the importance of cultural and educational changes to improve coping mechanisms. The objective of this study was to explore both the effects of patient death on academic emergency physicians (EPs) and the coping mechanisms they use to deal with these events. Faculty at a convenience sample of four emergency medicine (EM) residency programs were questioned about their responses to patient death in a 15-question on-line survey. Descriptive analysis of the data was performed. Independent variables were analyzed for differences in complaints of physical symptoms or consideration of important life changes after patient death. Of 207 EPs surveyed, 145 (70%) responded. Patient death was experienced frequently, with 95 (66%) witnessing a death at least every month. No training on coping with patient death had occurred for 35 (24%); 93 (64%) had less than 6 hours of training. The most common coping mechanisms included talking with colleagues (113; 78%) or friends and family (100; 69%), as well as simply continuing to work (89; 61%). Postdeath debriefing occurred rarely or never for 93 (64%) of respondents. Most EPs had experienced physical responses to patient death, the most common being insomnia (54; 37%) and fatigue (21; 14%). Common emotional responses included sadness (112; 70%) and disappointment (55; 38%). No significant differences in response rates for physical symptoms or consideration of life changes were found for any of the variables. Patient death was reported to lead to both physical and emotional symptoms in academic EPs. Postdeath debriefing appears to happen infrequently in teaching settings, and most respondents reported that they themselves received limited training in coping with patient death. Further study is needed to both identify coping mechanisms that are feasible and effective in emergency department settings and develop teaching strategies to incorporate this information into EM residency training. © 2011 by the Society for Academic Emergency Medicine.
Martín-Palomeque, Guillermo; Castro-Ortiz, Antonio; Pamplona-Valenzuela, Pilar; Saiz-Sepúlveda, Miguel Á; Cabañes-Martínez, Lidia; López, Jaime R
2017-01-01
Although large amplitude evoked potentials (EPs) are typically associated with progressive myoclonic epilepsy patients, giant EPs imply central nervous system (CNS) hyperexcitability and can be seen in various nonepileptic disorders. We performed a retrospective chart review including history, physical examination, imaging and diagnostic studies of nonepileptic patients with large amplitude somatosensory evoked potentials (SSEPs) and visual evoked potentials (VEPs) during 2007 to 2013. Large amplitude EPs were defined as follows: VEPs (N75-P100) >18 μV; and SSEPs (N20-P25) >6.4 μV. Recording montage for VEPs was Oz-Cz and SSEPs C3'/C4'-Fz. Fifty-two patients (33 females, 19 males; age range, 9-90 years) were identified. No CNS pathology was detected in 7 patients. All remaining patients were diagnosed with new CNS disorders including: vascular (37%); myelopathies (13%); demyelinating (11%); space occupying lesions (8.7%); syringomyelia (8.7%); hydrocephalus (6.5%); Vitamin B-12 deficiency (4.3%); multiple system atrophy (4.3%); and toxins (2.2%). This study supports the notion that large amplitude EP implies CNS hyperexcitability and CNS disease. These results confirm the utility of EP studies in patients with suspected CNS pathology.
Extracting physical quantities from BES data
NASA Astrophysics Data System (ADS)
Fox, Michael; Field, Anthony; Schekochihin, Alexander; van Wyk, Ferdinand; MAST Team
2015-11-01
We propose a method to extract the underlying physical properties of turbulence from measurements, thereby facilitating quantitative comparisons between theory and experiment. Beam Emission Spectroscopy (BES) diagnostics record fluctuating intensity time series, which are related to the density field in the plasma through Point-Spread Functions (PSFs). Assuming a suitable form for the correlation function of the underlying turbulence, analytical expressions are derived that relate the correlation parameters of the intensity field: the radial and poloidal correlation lengths and wavenumbers, the correlation time and the fluctuation amplitude, to the equivalent correlation properties of the density field. In many cases, the modification caused by the PSFs is substantial enough to change conclusions about physics. Our method is tested by applying PSFs to the ``real'' density field, generated by non-linear gyrokinetic simulations of MAST, to create synthetic turbulence data, from which the method successfully recovers the correlation function of the ``real'' density field. This method is applied to BES data from MAST to determine the scaling of the 2D structure of the ion-scale turbulence with equilibrium parameters, including the ExB flow shear. Work funded by the Euratom research and training programme 2014-2018 under grant agreement No 633053 and from the RCUK Energy Programme [grant number EP/I501045].
Proton Magnetic Form Factor from Existing Elastic e-p Cross Section Data
NASA Astrophysics Data System (ADS)
Ou, Longwu; Christy, Eric; Gilad, Shalev; Keppel, Cynthia; Schmookler, Barak; Wojtsekhowski, Bogdan
2015-04-01
The proton magnetic form factor GMp, in addition to being an important benchmark for all cross section measurements in hadron physics, provides critical information on proton structure. Extraction of GMp from e-p cross section data is complicated by two-photon exchange (TPE) effects, where available calculations still have large theoretical uncertainties. Studies of TPE contributions to e-p scattering have observed no nonlinear effects in Rosenbluth separations. Recent theoretical investigations show that the TPE correction goes to 0 when ɛ approaches 1, where ɛ is the virtual photon polarization parameter. In this talk, existing e-p elastic cross section data are reanalyzed by extrapolating the reduced cross section for ɛ approaching 1. Existing polarization transfer data, which is supposed to be relatively immune to TPE effects, are used to produce a ratio of electric and magnetic form factors. The extrapolated reduced cross section and polarization transfer ratio are then used to calculate GEp and GMp at different Q2 values.
Serial data acquisition for the X-ray plasma diagnostics with selected GEM detector structures
NASA Astrophysics Data System (ADS)
Czarski, T.; Chernyshova, M.; Pozniak, K. T.; Kasprowicz, G.; Zabolotny, W.; Kolasinski, P.; Krawczyk, R.; Wojenski, A.; Zienkiewicz, P.
2015-10-01
The measurement system based on GEM—Gas Electron Multiplier detector is developed for X-ray diagnostics of magnetic confinement tokamak plasmas. The paper is focused on the measurement subject and describes the fundamental data processing to obtain reliable characteristics (histograms) useful for physicists. The required data processing have two steps: 1—processing in the time domain, i.e. events selections for bunches of coinciding clusters, 2—processing in the planar space domain, i.e. cluster identification for the given detector structure. So, it is the software part of the project between the electronic hardware and physics applications. The whole project is original and it was developed by the paper authors. The previous version based on 1-D GEM detector was applied for the high-resolution X-ray crystal spectrometer KX1 in the JET tokamak. The current version considers 2-D detector structures for the new data acquisition system. The fast and accurate mode of data acquisition implemented in the hardware in real time can be applied for the dynamic plasma diagnostics. Several detector structures with single-pixel sensors and multi-pixel (directional) sensors are considered for two-dimensional X-ray imaging. Final data processing is presented by histograms for selected range of position, time interval and cluster charge values. Exemplary radiation source properties are measured by the basic cumulative characteristics: the cluster position distribution and cluster charge value distribution corresponding to the energy spectra. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics
Neoclassical Current Drive by Waves with a Symmetric Spectrum
NASA Astrophysics Data System (ADS)
Helander, Per
2000-10-01
It is well known that plasma waves can produce electric currents if the waves have an asymmetric spectrum, so that they either interact preferentially with electrons travelling in one direction along the magnetic field or impart net parallel momentum to the electrons [1]. This directionality creates an asymmetry in the electron distribution function and thereby produces a current parallel to the field. We demonstrate, somewhat surprisingly, that in a plasma confined by a curved magnetic field no such spectral asymmetry is necessary for current drive if the effect of collisions is properly taken into account. For instance, in a toroidal plasma a current can be produced by a spectrally symmetric wave field if this field is instead up-down asymmetric, which is frequently the case for electron cyclotron current drive (ECCD) in tokamaks. We have calculated the resulting current drive efficiency and found it to be smaller than that of the conventional current drive mechanism in the banana regime, but not insignificant in the plateau regime. The results will be compared with experiments in DIII-D, where the measured efficiency exceeds the classical prediction [2]. Our calculations are focused on this case of ECCD in tokamaks, but the basic physical mechanism is much more general. It is of a universal neoclassical nature and applies to all wave-particle interaction in curved magnetic fields. [1] N.J. Fisch, Rev. Mod. Phys. 59, 175 (1987). [2] Y. R. Lin-Liu et al., 26th EPS Conf. on Contr. Fusion and Plasma Phys.(European Phys. Soc. Paris, 1999) Vol. 23J, p 1245.
PR2EPS: Preparation, Recruitment, Retention and Excellence in the Physical Sciences
NASA Astrophysics Data System (ADS)
Gallagher, Hugh
2005-04-01
PR2EPS, is an NSF-DUE sponsored program at SUNY Oneonta designed to attract students to pursue physics, chemistry and related physical science degrees in college. For those students who choose to study at SUNY Oneonta, the program also seeks to increase the retention rate of all students in the physical sciences by providing specialized skills and professional development courses, an evening tutoring center, and exposure to research and professional activities early in their undergraduate careers. A key focus of the project is drawing students from the five, primarily rural and agricultural, counties surrounding Oneonta, NY. Their first direct exposure to the program will be in recruiting visits to local high schools where promising candidates will be invited to participate in a weeklong summer camp designed to demonstrate to them that they possess the requisite skills and potential to succeed in these technically demanding disciplines. We will provide a brief description of the program and discuss outcomes of the first year including the inaugural summer camp.
Zhang, Zhiqiang; Zhou, Yun; Zhang, Jiao; Xia, Siqing
2014-02-01
The extracellular polymeric substance (EPS) extracted from waste activated sludge (WAS) after short-time aerobic digestion was investigated to be used as a novel biosorbent for Cu(2+) removal from water. The EPS consisted of protein (52.6 %, w/w), polysaccharide (30.7 %, w/w), and nucleic acid (16.7 %, w/w). Short-time aerobic digestion process of WAS for about 4 h promoted the productivity growth of the EPS for about 10 %. With a molecular weight of about 1.9 × 10(6) Da, the EPS showed a linear structure with long chains, and contained carboxyl, hydroxyl, and amino groups. The sorption kinetics was well fit for the pseudo-second-order model, and the maximum sorption capacity of the EPS (700.3 mg Cu(2+)/g EPS) was markedly greater than those of the reported biosorbents. Both Langmuir model and Freundlich model commendably described the sorption isotherm. The Gibbs free energy analysis of the adsorption showed that the sorption process was feasible and spontaneous. According to the complex results of multiple analytical techniques, including scanning electron microscopy, Fourier transform infrared spectroscopy, atomic force microscopy, etc., the adsorption process took place via both physical and chemical sorption, but the electrostatic interaction between sorption sites with the functional groups and Cu(2+) is the major mechanism.
PR^2EPS: Preparation, recruitment, retention and excellence in the physical sciences
NASA Astrophysics Data System (ADS)
Gallagher, Hugh; Labroo, Sunil; Schaumloffel, John; Bischoff, Paul; Bachman, Nancy
2007-04-01
The PR^2EPS program is a multidisciplinary effort to increase the number of majors attending (and graduating) from SUNY Oneonta with degrees in physics, chemistry, secondary physics or chemistry education and related areas. Components of the program include a walk-in tutoring center, a free, weeklong summer science camp, scholarship opportunities, professional conference experiences, and an equipment loan program for regional secondary science teachers. 2006 was the third year of this NSF-DUE funded program. Evaluation of our progress to date shows that the program is effective at steering students (or at least reinforcing their desire) to studying the sciences in college and retaining them in their science programs. A summary of our goals, challenges and accomplishments, including tutoring center operation and efficacy, activities and operational details for the summer camp, and the overall impact on science programs at a medium sized college will be presented.
Nickel cadmium battery expert system
NASA Technical Reports Server (NTRS)
1986-01-01
The applicability of artificial intelligence methodologies for the automation of energy storage management, in this case, nickel cadmium batteries, is demonstrated. With the Hubble Space Telescope Electrical Power System (HST/EPS) testbed as the application domain, an expert system was developed which incorporates the physical characterization of the EPS, in particular, the nickel cadmium batteries, as well as the human's operational knowledge. The expert system returns not only fault diagnostics but also status and advice along with justifications and explanations in the form of decision support.
DE-NE0008277_PROTEUS final technical report 2018
DOE Office of Scientific and Technical Information (OSTI.GOV)
Enqvist, Andreas
This project details re-evaluations of experiments of gas-cooled fast reactor (GCFR) core designs performed in the 1970s at the PROTEUS reactor and create a series of International Reactor Physics Experiment Evaluation Project (IRPhEP) benchmarks. Currently there are no gas-cooled fast reactor (GCFR) experiments available in the International Handbook of Evaluated Reactor Physics Benchmark Experiments (IRPhEP Handbook). These experiments are excellent candidates for reanalysis and development of multiple benchmarks because these experiments provide high-quality integral nuclear data relevant to the validation and refinement of thorium, neptunium, uranium, plutonium, iron, and graphite cross sections. It would be cost prohibitive to reproduce suchmore » a comprehensive suite of experimental data to support any future GCFR endeavors.« less
Garza-Gonzalez, Maria Teresa; Gonzalez Garza, Maria Teresa; Barboza Perez, Daniel; Vazquez Rodriguez, Augusto; Garcia-Gutierrez, Domingo Ixcoatl; Zarate, Xristo; Cantú Cardenas, Maria Elena; Urraca-Botello, Ludwing Ilytch; Lopez-Chuken, Ulrico Javier; Trevino-Torres, Alberto Ludovico; Cerino-Córdoba, Felipe de Jesus; Medina-Ruiz, Pavel; Villarreal-Chiu, Juan Francisco; Morones-Ramirez, Jose Ruben
2016-01-01
There is a current need to develop low-cost strategies to degrade and eliminate industrially used colorants discharged into the environment. Colorants discharged into natural water streams pose various threats, including: toxicity, degradation of aesthetics and inhibiting sunlight penetration into aquatic ecosystems. Dyes and colorants usually have complex aromatic molecular structures, which make them very stable and difficult to degrade and eliminate by conventional water treatment systems. The results in this work demonstrated that heavy metal-resistant Rhodotorula mucilaginosa strain UANL-001L isolated from the northeast region of Mexico produce an exopolysaccharide (EPS), during growth, which has colorant adsorption potential. The EPS produced was purified by precipitation and dialysis and was then physically and chemically characterized by Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, and chemical elemental analysis. Here, the ability of the purified EPS produced to adsorb methylene blue (MB), which served as a model colorant, is studied. MB adsorption by the EPS is found to follow Langmuir Adsorption Isotherm kinetics at 25°C. Further, by calculating the Langmuir constant the adsorption capabilities of the EPS produced by the Rhodotorula mucilaginosa strain UANL-001L is compared to that of other adsorbents, both, microbially produced and from agroindustrial waste. The total adsorption capacity of the EPS, from the Rhodotorula mucilaginosa strain UANL-001L, was found to be two-fold greater than the best bioadsorbents reported in the literature. Finally, apart from determining which heavy metals stimulated EPS production in the strain, the optimal conditions of pH, heavy metal concentration, and rate of agitation of the growing culture for EPS production, was determined. The EPS reported here has the potential of aiding in the efficient removal of colorants both in water treatment plants and in situ in natural water streams.
Vazquez Rodriguez, Augusto; Garcia-Gutierrez, Domingo Ixcoatl; Zarate, Xristo; Cantú Cardenas, Maria Elena; Urraca-Botello, Ludwing Ilytch; Lopez-Chuken, Ulrico Javier; Trevino-Torres, Alberto Ludovico; Cerino-Córdoba, Felipe de Jesus; Medina-Ruiz, Pavel; Villarreal-Chiu, Juan Francisco; Morones-Ramirez, Jose Ruben
2016-01-01
There is a current need to develop low-cost strategies to degrade and eliminate industrially used colorants discharged into the environment. Colorants discharged into natural water streams pose various threats, including: toxicity, degradation of aesthetics and inhibiting sunlight penetration into aquatic ecosystems. Dyes and colorants usually have complex aromatic molecular structures, which make them very stable and difficult to degrade and eliminate by conventional water treatment systems. The results in this work demonstrated that heavy metal-resistant Rhodotorula mucilaginosa strain UANL-001L isolated from the northeast region of Mexico produce an exopolysaccharide (EPS), during growth, which has colorant adsorption potential. The EPS produced was purified by precipitation and dialysis and was then physically and chemically characterized by Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, and chemical elemental analysis. Here, the ability of the purified EPS produced to adsorb methylene blue (MB), which served as a model colorant, is studied. MB adsorption by the EPS is found to follow Langmuir Adsorption Isotherm kinetics at 25°C. Further, by calculating the Langmuir constant the adsorption capabilities of the EPS produced by the Rhodotorula mucilaginosa strain UANL-001L is compared to that of other adsorbents, both, microbially produced and from agroindustrial waste. The total adsorption capacity of the EPS, from the Rhodotorula mucilaginosa strain UANL-001L, was found to be two-fold greater than the best bioadsorbents reported in the literature. Finally, apart from determining which heavy metals stimulated EPS production in the strain, the optimal conditions of pH, heavy metal concentration, and rate of agitation of the growing culture for EPS production, was determined. The EPS reported here has the potential of aiding in the efficient removal of colorants both in water treatment plants and in situ in natural water streams. PMID:26828867
Levitt, N C; Propper, D J; Madhusudan, S; Braybrooke, J P; Echeta, C; Te Poele, R; Davies, S L; Flanagan, E; Hickson, I D; Joel, S; Ganesan, T S
2005-07-11
A pharmacokinetically guided phase I study of topotecan and etoposide phosphate was conducted in recurrent ovarian cancer. The scheduling of the topoisomerase I and II inhibitors was determined using in vitro activity data. All patients had recurrent disease following prior platinum-containing chemotherapy. Patients had a World Health Organisation performance status of 0-2 and adequate bone marrow, renal and hepatic function. Treatment was with topotecan intravenously for 5 days followed immediately by a 5-day intravenous infusion of etoposide phosphate (EP), with pharmacokinetically guided dose adjustment. Plasma etoposide levels were measured on days 2 and 4 of the infusion. A total of 21 patients entered the study. In all, 48% were platinum resistant and 71% had received prior paclitaxel. The main toxicities were haematological, short lived and reversible. A total of 29% of patients experienced grade 4 thrombocytopenia and 66% grade 4 neutropenia after the first cycle. Neutropenia and thrombocytopenia was dose limiting. The maximum-tolerated dose was topotecan 0.85 mg m(-2) day(-1) days 1-5 followed immediately by a 5-day infusion of EP at a plasma concentration of 1 mug ml(-1). The response rate (RR) was 28% in 18 evaluable patients. There was marked interpatient variability in topoisomerase IIalpha levels measured from peripheral lymphocytes, with no observed increase following topotecan. This regimen of topotecan followed by EP demonstrated good activity in recurrent ovarian cancer and was noncrossresistant with paclitaxel. Both the toxicity and RR was higher than would be expected from the single agent data, in keeping with synergy of action.
Campbell, Jay M.; Zhang, Nianli; Hickey, William J.
2012-01-01
Abstract Modern ecological niches are teeming with an astonishing diversity of microbial life in biofilms closely associated with mineral surfaces, which highlights the remarkable success of microorganisms in conquering the challenges and capitalizing on the benefits presented by the mineral–water interface. Biofilm formation capability likely evolved on early Earth because biofilms provide crucial cell survival functions. The potential toxicity of mineral surfaces toward cells and the complexities of the mineral–water–cell interface in determining the toxicity mechanisms, however, have not been fully appreciated. Here, we report a previously unrecognized role for extracellular polymeric substances (EPS), which form biofilms in shielding cells against the toxicity of mineral surfaces. Using colony plating and LIVE/DEAD staining methods in oxide suspensions versus oxide-free controls, we found greater viability of wild-type, EPS-producing strains of Pseudomonas aeruginosa PAO1 compared to their isogenic knockout mutant with defective biofilm-producing capacity. Oxide toxicity was specific to its surface charge and particle size. High resolution transmission electron microscopy (HRTEM) images and assays for highly reactive oxygen species (hROS) on mineral surfaces suggested that EPS shield via both physical and chemical mechanisms. Intriguingly, qualitative as well as quantitative measures of EPS production showed that toxic minerals induced EPS production in bacteria. By determining the specific toxicity mechanisms, we provide insight into the potential impact of mineral surfaces in promoting increased complexity of cell surfaces, including EPS and biofilm formation, on early Earth. Key Words: Mineral toxicity—Bacteria—EPS evolution—Biofilms—Cytotoxicity—Silica—Anatase—Alumina. Astrobiology 12, 785–798. PMID:22934560
Validating predictive models for fast ion profile relaxation in burning plasmas
NASA Astrophysics Data System (ADS)
Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; Lestz, J. B.; Podesta, M.; Van Zeeland, M. A.; White, R. B.
2016-11-01
The redistribution and potential loss of energetic particles due to MHD modes can limit the performance of fusion plasmas by reducing the plasma heating rate. In this work, we present validation studies of the 1.5D critical gradient model (CGM) for Alfvén eigenmode (AE) induced EP transport in NSTX and DIII-D neutral beam heated plasmas. In previous comparisons with a single DIII-D L-mode case, the CGM model was found to be responsible for 75% of measured AE induced neutron deficit [1]. A fully kinetic HINST is used to compute mode stability for the non-perturbative version of CGM (or nCGM). We have found that AEs show strong local instability drive up to γ /ω ∼ 20% violating assumptions of perturbative approaches used in NOVA-K code. We demonstrate that both models agree with each other and both underestimate the neutron deficit measured in DIII-D shot by approximately a factor of 2. On the other hand in NSTX the application of CGM shows good agreement for the measured flux deficit predictions. We attempt to understand these results with the help of the so-called kick model which is based on the guiding center code ORBIT. The kick model comparison gives important insight into the underlying velocity space dependence of the AE induced EP transport as well as it allows the estimate of the neutron deficit in the presence of the low frequency Alfvénic modes. Within the limitations of used models we infer that there are missing modes in the analysis which could improve the agreement with the experiments.
Pitteri, Sharon J.; Amon, Lynn M.; Buson, Tina Busald; Zhang, Yuzheng; Johnson, Melissa M.; Chin, Alice; Kennedy, Jacob; Wong, Chee-Hong; Zhang, Qing; Wang, Hong; Lampe, Paul D.; Prentice, Ross L.; McIntosh, Martin W.; Hanash, Samir M.; Li, Christopher I.
2010-01-01
Applying advanced proteomic technologies to prospectively collected specimens from large studies is one means of identifying preclinical changes in plasma proteins that are potentially relevant to the early detection of diseases like breast cancer. We conducted fourteen independent quantitative proteomics experiments comparing pooled plasma samples collected from 420 estrogen receptor positive (ER+) breast cancer patients ≤17 months prior to their diagnosis and matched controls. Based on the over 3.4 million tandem mass spectra collected in the discovery set, 503 proteins were quantified of which 57 differentiated cases from controls with a p-value<0.1. Seven of these proteins, for which quantitative ELISA assays were available, were assessed in an independent validation set. Of these candidates, epidermal growth factor receptor (EGFR) was validated as a predictor of breast cancer risk in an independent set of preclinical plasma samples for women overall [odds ratio (OR)=1.44, p-value=0.0008], and particularly for current users of estrogen plus progestin (E+P) menopausal hormone therapy (OR=2.49, p-value=0.0001). Among current E+P users EGFR's sensitivity for breast cancer risk was 31% with 90% specificity. While EGFR's sensitivity and specificity are insufficient for a clinically useful early detection biomarker, this study suggests that proteins that are elevated preclinically in women who go on to develop breast cancer can be discovered and validated using current proteomic technologies. Further studies are warranted to both examine the role of EGFR and to discover and validate other proteins that could potentially be used for breast cancer early detection. PMID:20959476
Morelle, Jérôme; Schapira, Mathilde; Claquin, Pascal
2017-10-01
Exopolysaccharides (EPS) play an important role in the carbon flux and may be directly linked to phytoplankton and microphytobenthos production, most notably in estuarine systems. However the temporal and spatial dynamics of estuarine EPS are still not well understood, nor how primary productivity triggers this variability at these different scales. The aim of this study was to investigate the primary productivity of phytoplankton and EPS dynamics in the Seine estuary over a tidal cycle in three different haline zones over two contrasted seasons. The other objectives was to investigate the origin of pools of soluble carbohydrates (S-EPS) and transparent exopolymeric particles (TEP) in phytoplankton, microphytobenthos or other compartments. High frequency measurements of productivity were made in winter and summer 2015. Physical and chemical parameters, biomass and EPS were measured at hourly intervals in sub-surface waters and just above the water sediment-interface. Our results confirmed that high frequency measurements improve the accuracy of primary productivity estimations and associated carbon fluxes in estuaries. The photosynthetic parameters were shown to be strongly controlled by salinity and by the concentrations of suspended particle matter at the smallest temporal and at spatial scales. At these scales, our results showed an inverse relationship between EPS concentrations and biomass and productivity, and a positive relationship with sediment resuspension. Additionally, the distribution of EPS appears to be linked to hydrodynamics with the tide at daily scale and with the winter at seasonal scale. At spatial scale, the maximum turbidity zone played an important role in the distribution of TEP. Our results suggest that, in the Seine estuary, between 9% and 33% of the S-EPS pool in the water column can be attributed to phytoplankton excretion, while only 0.4%-1.6% (up to 6.14% in exceptional conditions) originates from the microphytobenthos compartments. Most EPS was attributed to remobilization of detrital carbon pools in the maximum turbidity zone and in the sediment or allochthonous origin. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
2016-07-01
The Meeting was sponsored by the Istituto Nazionale di Fisica Nucleare (INFN), the Società Italiana di Fisica (SIF), the European Physics Society (EPS), the University of Pisa and the University of Siena.
Wang, Zhigang; Fu, Zhenguo; He, Bin; Hu, Zehua; Zhang, Ping
2016-09-01
The nuclear plus interference scattering (NIS) effect on the stopping power of hot dense beryllium (Be) plasma for multi-MeV protons is theoretically investigated by using the generalized Brown-Preston-Singleton (BPS) model, in which a NIS term is taken into account. The analytical formula of the NIS term is detailedly derived. By using this formula, the density and temperature dependence of the NIS effect is numerically studied, and the results show that the NIS effect becomes more and more important with increasing the plasma temperature or density. Different from the cases of protons traveling through the deuterium-tritium plasmas, for a Be plasma, a prominent oscillation valley structure is observed in the NIS term when the proton's energy is close to E_{p}=7MeV. Furthermore, the penetration distance is remarkably reduced when the NIS term is considered.
Novel diagnostics for direct measurements of radical densities in atmospheric pressure plasma jets
NASA Astrophysics Data System (ADS)
Wagenaars, Erik
2017-10-01
Atmospheric-pressure plasma jets (APPJs) are widely studied for potential applications in industry and healthcare, e.g. surface modification of plastics, plasma medicine and photoresist removal. These plasmas can operate in open air, remain at room temperature and still have a non-equilibrium chemistry. Even though the exact mechanisms through which APPJs affect target surfaces remain largely unknown, it is clear that reactive species play a pivotal role in the success of APPJs. Therefore, reactive species diagnostics of APPJs play an important role in further developing our understanding of the plasma chemistry and will enable increases in treatment efficacy. Two-photon Absorption Laser Induced Fluorescence (TALIF) is a well-known technique for the measurement of absolute densities of atomic radicals such as O, N and H. Unfortunately, application of this technique on APPJs that are operating under realistic conditions for applications, i.e. in open air and with complex admixtures, is not straightforward. The highly collisional environment of APPJs means that collisional quenching of the laser-excited state becomes significant and needs to be taken into account. For well-controlled atmospheres and simple admixtures the effect can be estimated using quenching coefficients, however under realistic operating conditions the identity and density of the quenching partners is unknown due to the complexity of the plasma chemistry. I will present a picosecond TALIF diagnostic which uses a sub-nanosecond laser and iCCD camera that allows the measurement of the quenching-affected fluorescence decay rate directly, enabling absolute measurements of O and N density maps in the open-air effluent of an APPJ. The author acknowledges his collaborators at UoY, A. West, J. Bredin, S. Schroeter, K. Niemi, T. Gans, J. Dedrick and D. O'Connell and support from the UK EPSRC (EP/K018388/1 & EP/H003797/1).
Tréluyer, Jean-Marc; Illamola, Silvia M.; Bouazza, Naïm; Foissac, Frantz; De Sousa Mendes, Maïlys; Lui, Gabrielle; Chenevier-Gobeaux, Camille; Suzan-Monti, Marie; Rouzioux, Christine; Assoumou, Lambert; Viard, Jean-Paul; Hirt, Déborah; Urien, Saïk; Ghosn, Jade
2015-01-01
We aimed to describe blood plasma (BP) and seminal plasma (SP) pharmacokinetics of emtricitabine (FTC) in HIV-1-infected men, assess its penetration in the male genital tract, and evaluate its impact on seminal plasma HIV load (spVL) detection. Men from the EVARIST ANRS EP49 study receiving combined antiretroviral therapy with FTC and with suppressed BP viral load were included in the study. A total of 236 and 209 FTC BP and SP concentrations, respectively, were available. A population pharmacokinetic model was developed with Monolix 4.1.4. The impact of FTC seminal exposure on spVL detection was explored by receiver operating characteristic (ROC) curves and mixed-effects logistic regressions. FTC BP pharmacokinetics was described by a two-compartment model. The addition of an effect compartment with different input and output constants best described FTC SP pharmacokinetics. No covariates were found to explain the variability in SP. FTC exposures (area under the concentration-time curve from 0 to 24 h [AUC0–24]) were higher in SP than in BP (median AUC0–24, 38.04 and 12.95 mg · liter−1 · h, respectively). The median (range) SP-to-BP AUC0–24 ratio was 2.91 (0.84 to 10.08). Less than 1% of FTC AUC0–24 ratios were lower than 1. The impact of FTC SP AUC0–24 or FTC SP-to-BP AUC0–24 ratio on spVL detection was not significant (P = 0.943 or 0.893, respectively). This is the first population model describing FTC pharmacokinetics simultaneously in both BP and SP. FTC distributes well in the male genital tract with higher FTC concentrations in SP than in BP. FTC seminal plasma exposures were considered efficient in the majority of men. PMID:26282407
Mastoraki, Sophia; Strati, Areti; Tzanikou, Eleni; Chimonidou, Maria; Politaki, Eleni; Voutsina, Alexandra; Psyrri, Amanda; Georgoulias, Vassilis; Lianidou, Evi
2018-03-15
Purpose: Liquid biopsy provides real-time monitoring of tumor evolution and response to therapy through analysis of circulating tumor cells (CTCs) and plasma-circulating tumor DNA (ctDNA). ESR1 epigenetic silencing potentially affects response to endocrine treatment. We evaluated ESR1 methylation in CTCs and paired plasma ctDNA. We evaluated ESR1 methylation in CTCs and paired plasma ctDNA as a potential biomarker for response to everolimus/exemestane treatment. Experimental Design: A highly sensitive and specific real-time MSP assay for ESR1 methylation was developed and validated in (i) 65 primary breast tumors formalin-fixed paraffin-embedded (FFPE), (ii) EpCAM + CTC fractions (122 patients and 30 healthy donors; HD), (iii) plasma ctDNA (108 patients and 30HD), and (iv) in CTCs (CellSearch) and in paired plasma ctDNA for 58 patients with breast cancer. ESR1 methylation status was investigated in CTCs isolated from serial peripheral blood samples of 19 patients with ER + /HER2 - advanced breast cancer receiving everolimus/exemestane. Results: ESR1 methylation was detected in: (i) 25/65 (38.5%) FFPEs, (ii) EpCAM + CTC fractions : 26/112 (23.3%) patients and 1/30 (3.3%) HD, and (iii) plasma ctDNA: 8/108 (7.4%) patients and 1/30 (3.3%) HD. ESR1 methylation was highly concordant in 58 paired DNA samples, isolated from CTCs (CellSearch) and corresponding plasma. In serial peripheral blood samples of patients treated with everolimus/exemestane, ESR1 methylation was observed in 10/36 (27.8%) CTC-positive samples, and was associated with lack of response to treatment ( P = 0.023, Fisher exact test). Conclusions: We report for the first time the detection of ESR1 methylation in CTCs and a high concordance with paired plasma ctDNA. ESR1 methylation in CTCs was associated with lack of response to everolimus/exemestane regimen. ESR1 methylation should be further evaluated as a potential liquid biopsy-based biomarker. Clin Cancer Res; 24(6); 1500-10. ©2017 AACR . ©2017 American Association for Cancer Research.
Education for Today's Ecological Crisis
ERIC Educational Resources Information Center
Singer, S. Fred
1970-01-01
Describes the university's role in providing education for the ecological crisis, and divides environmental sciences into two major areas: basic and applied. Proposes a curriculum leading to a B.S. degree in physics consisting of a two-year honor physics program followed by specialization in environmental and planetary sciences (EPS). (PR)
PREFACE: 1982 International Conference on Plasma Physics
NASA Astrophysics Data System (ADS)
Wilhelmsson, Hans
1982-01-01
Invited Papers: The Physics of Hot Plasmas During the last decade a dramatic evolution of plasma physics has occurred. Not only have gigantic fusion plasma machines been planned, and are now being built, and elaborate spaceships and antenna systems been constructed to explore remote parts of the cosmos; new observations have revealed fascinating structures in space, ranging from pulsar plasmas under extreme conditions in very strong magnetic fields to large-scale magnetic field and electric current systems in cosmic plasmas. X-rays from very distant sources as well as radio-waves from the plasma in the magnetosphere and in the Aurora have recently been studied with new observational techniques. Ingenious laboratory experiments are continuously being carried out to exploit new fundamental processes in plasmas. These are of great interest for the basic understanding of plasmas and also have immediate consequences for applications, like plasma heating and diagnostics. The theoretical description of new plasma phenomena, and of the plasma state in general poses challenging problems, particularly in situations where high concentration of energy is located in the plasmas. Nonlinear wave analysis and turbulence theory have accordingly been extensively developed to describe in particular the collective plasma phenomena. New concepts have been envisaged like plasma solitons, which may be thought of as excitations of local concentrations of longitudinal plasma waves which turn out to be particularly stable. More and more sophisticated structures of nonlinear nature are being revealed by means of high capacity computer facilities. Simulation experiments allow for studies of chaotic behaviour of plasma particles. Related fields of activity form new trends in the development of plasma theory. The programme of the 1982 International Conference on Plasma Physics, which was held in Göteborg, Sweden, stressed the role of the Physics of Hot Plasmas. Studies of such plasmas are essential, not only for fusion energy development, but also for astro- and space research. Plasmas in different situations often have important features in common. Results obtained under various conditions, in the laboratory or in space, should therefore be compared and interrelated. The Göteborg conference emphasized more than the previous one, which was held in Nagoya, Japan, the astro- and space aspects, but there were still more contributions from the fusion and laboratory research. The fundamental plasma theory part was, however, the most extensive one in the programme. At the conference there were seventy invited talks, including six comprehensive talks addressed to all participants. The remaining sixtyfour invited talks were topical talks. Besides, we had received about 450 contributed papers. About 300 of them were given as posters, and most of the remaining ones were presented as orals. The set of one page abstracts of these contributed papers as well as the titles of the invited talks were collected in two volumes, which were sent to all participants a month before the conference. Another set, the four page papers, which had been carefully prepared by the authors for photoreproduction to one page papers, were published in a volume of proceedings of some 460 pages available at the conference. When trying to classify the contributions, it turned out that they fell naturally into four main categories, namely: General Theory Space and Astro Plasmas Fusion Laboratory Plasmas For practical reasons we had to divide the Abstracts into two Volumes, the first one including categories (1) and (2), and the second one the two remaining categories (3) and (4). In publishing the invited talks from the conference we had to handle a great number of extensive papers. It turned out to be natural to have also the invited papers published in two parts, as two separate numbers of Physica Scripta, the first one devoted to (1) General Theory, and (2) Space and Astro Plasmas, whereas the second one to (3) Fusion and (4) Laboratory Plasmas. The 1982 International Conference on Plasma Physics was organized by Chalmers University of Technology. It gathered about 500 participants from 40 countries. Large delegations came from the USA, France, West Germany, Japan, the USSR, and India, the number of participants from these countries ranging from 100 to 20. Sweden had about 50 participating scientists. There were a total of about 20 from the other Scandinavian countries. The principal sponsor of the conference was IUPAP, the International Union of Pure and Applied Physics. The conference also had a number of co-sponsors like IAU, the International Astronomical Union, URSI, the International Union of Radio Science, EPS, the European Physical Society, and EURATOM-FUSION. The conference was supported by Swedish Industry and Swedish Research Boards. The previous ICPP, held in Nagoya two years ago, was the first attempt to combine two types of conferences: the Plasma Theory Conference, first held in Kiev in the Soviet Union in 1971, and the Waves and Instabilities Congress, held for the first time in Innsbruck, Austria in 1973. As a consequence of the success of the Nagoya conference it was decided by the International Organizing Committee of the ICPP that the 1982 conference should also be of the combined type. The 1982 ICPP in Göteborg was thus a Joint Conference of the Fifth Kiev International Conference in Plasma Theory and the Fifth International Congress on Waves and Instabilities in Plasmas. During the conference in Göteborg the International Organizing Committee had a meeting and it was decided that also the next International Conference on Plasma Physics will be of the combined type. It will be held in Lausanne, Switzerland in 1984. The International Organizing Committee on the 1982 International Conference on Plasma Physics comprised about 40 plasma physics scientists from all over the world, who represented various sections of plasma physics. I would like to thank the active members of the IOC for an efficient and friendly co-operation in deciding about the program of invited speakers and for discussions on the general structure of the conference. Our most cordial thanks are extended to the invited speakers for coming to the conference to deliver such excellent talks and to provide us in good time for printing with so beautifully prepared manuscripts. Symposium on Plasma Theory: Preface Several satellite meetings were arranged following the 1982 International Conference on Plasma Physics in Göteborg. Among them a Symposium on Plasma Theory was held at Aspenäsgården outside Göteborg during three days, June 16-18, 1982. The purpose of the symposium was to discuss problems of current interest in plasma theory with applications to space and astrophysical plasmas as well as to fusion plasmas. A total of fifteen talks were given during the three days, and some very lively discussions arose, notably in the area of plasma turbulence. There were around 30 invited scientists present, about one third from the United States, one third from the Soviet Union, and the rest from England, Japan, and various other countries. This volume of Physica Scripta (2B, 506-595) includes some of the talks which were given at Aspenäsgården. Several of the authors of contributed papers to the 1982 International Conference on Plasma Physics were encouraged to write extended versions of their contributions, and these are also included in this number, as are furthermore some papers, which were prepared during prolonged stays of visiting scientists at our institute in connection with the 1982 ICPP. It is expected that the collection of papers thus assembled will give a general picture of the activities accompanying the main conference and that it will elucidate some trends in the development of plasma theory.
EPS (Electric Particulate Suspension) Microgravity Technology Provides NASA with New Tools
NASA Technical Reports Server (NTRS)
Colver, Gerald M.; Greene, Nate; Xu, Hua
2004-01-01
The Electric Particulate Suspension is a fire safety ignition test system being developed at Iowa State University with NASA support for evaluating combustion properties of powders, powder-gas mixtures, and pure gases in microgravity and gravitational atmospheres (quenching distance, ignition energy, flammability limits). A separate application is the use of EPS technology to control heat transfer in vacuum and space environment enclosures. In combustion testing, ignitable powders (aluminum, magnesium) are introduced in the EPS test cell and ignited by spark, while the addition of inert particles act as quenching media. As a combustion research tool, the EPS method has potential as a benchmark design for quenching powder flames that would provide NASA with a new fire safety standard for powder ignition testing. The EPS method also supports combustion modeling by providing accurate measurement of flame-quenching distance as an important parameter in laminar flame theory since it is closely related to characteristic flame thickness and flame structure. In heat transfer applications, inert powder suspensions (copper, steel) driven by electric fields regulate heat flow between adjacent surfaces enclosures both in vacuum (or gas) and microgravity. This simple E-field control can be particularly useful in space environments where physical separation is a requirement between heat exchange surfaces.
Chemical and rheological properties of exopolysaccharides produced by four isolates of rhizobia.
Moretto, Cristiane; Castellane, Tereza Cristina Luque; Lopes, Erica Mendes; Omori, Wellington Pine; Sacco, Laís Postai; Lemos, Eliana Gertrudes de Macedo
2015-11-01
The rheological, physicochemical properties, emulsification and stability of exopolysaccharides (EPSs) from four rhizobia isolates (LBMP-C01, LBMP-C02, LBMP-C03 and LBMP-C04) were studied. The EPS yields of isolates under these experimental conditions were in the range of 1.5-6.63gL(-1). The LBMP-C04 isolate, which presented the highest EPS production (6.63gL(-1)), was isolated from Arachis pintoi and was identified as a Rhizobium sp. strain that could be explored as a possible potential source for the production of extracellular heteropolysaccharides. All polymers showed a pseudoplastic non-Newtonian fluid behavior or shear thinning property in aqueous solutions. Among the four EPS tested against hydrocarbons, EPS LBMP-C01 was found to be more effective against hexane, olive and soybean oils (89.94%, 82.75% and 81.15%, respectively). Importantly, we found that changes in pH (2-11) and salinity (0-30%) influenced the emulsification of diesel oil by the EPSs. EPSLBMP-C04 presented optimal emulsification capacity at pH 10 (E24=53%) and 30% salinity (E24=27%). These findings contribute to the understanding of the influence of the chemical composition, physical properties and biotechnology applications of rhizobial EPS solutions their bioemulsifying properties. Copyright © 2015 Elsevier B.V. All rights reserved.
One-dimensional energetic particle quasilinear diffusion for realistic TAE instabilities
NASA Astrophysics Data System (ADS)
Duarte, Vinicius; Ghantous, Katy; Berk, Herbert; Gorelenkov, Nikolai
2014-10-01
Owing to the proximity of the characteristic phase (Alfvén) velocity and typical energetic particle (EP) superthermal velocities, toroidicity-induced Alfvén eigenmodes (TAEs) can be resonantly destabilized endangering the plasma performance. Thus, it is of ultimate importance to understand the deleterious effects on the confinement resulting from fast ion driven instabilities expected in fusion-grade plasmas. We propose to study the interaction of EPs and TAEs using a line broadened quasilinear model, which captures the interaction in both regimes of isolated and overlapping modes. The resonance particles diffuse in the phase space where the problem essentially reduces to one dimension with constant kinetic energy and the diffusion mainly along the canonical toroidal angular momentum. Mode structure and wave particle resonances are computed by the NOVA code and are used in a quasilinear diffusion code that is being written to study the evolution of the distribution function, under the assumption that they can be considered virtually unalterable during the diffusion. A new scheme for the resonant particle diffusion is being proposed that builds on the 1-D nature of the diffusion from a single mode, which leads to a momentum conserving difference scheme even when there is mode overlap.
Entropy-driven motility of Sinorhizobium meliloti on a semi-solid surface
Dilanji, Gabriel E.; Teplitski, Max; Hagen, Stephen J.
2014-01-01
Sinorhizobium meliloti growing on soft agar can exhibit an unusual surface spreading behaviour that differs from other bacterial surface motilities. Bacteria in the colony secrete an exopolysaccharide-rich mucoid fluid that expands outward on the surface, carrying within it a suspension of actively dividing cells. The moving slime disperses the cells in complex and dynamic patterns indicative of simultaneous bacterial growth, swimming and aggregation. We find that while flagellar swimming is required to maintain the cells in suspension, the spreading and the associated pattern formation are primarily driven by the secreted exopolysaccharide EPS II, which creates two entropy-increasing effects: an osmotic flow of water from the agar to the mucoid fluid and a crowding or depletion attraction between the cells. Activation of these physical/chemical phenomena may be a useful function for the high molecular weight EPS II, a galactoglucan whose biosynthesis is tightly regulated by the ExpR/SinI/SinR quorum-sensing system: unlike bacterial colonies that spread via bacterium-generated, physical propulsive forces, S. meliloti under quorum conditions may use EPS II to activate purely entropic forces within its environment, so that it can disperse by passively ‘surfing’ on those forces. PMID:24741008
Ship electric propulsion simulator based on networking technology
NASA Astrophysics Data System (ADS)
Zheng, Huayao; Huang, Xuewu; Chen, Jutao; Lu, Binquan
2006-11-01
According the new ship building tense, a novel electric propulsion simulator (EPS) had been developed in Marine Simulation Center of SMU. The architecture, software function and FCS network technology of EPS and integrated power system (IPS) were described. In allusion to the POD propeller in ship, a special physical model was built. The POD power was supplied from the simulative 6.6 kV Medium Voltage Main Switchboard, its control could be realized in local or remote mode. Through LAN, the simulated feature information of EPS will pass to the physical POD model, which would reflect the real thruster working status in different sea conditions. The software includes vessel-propeller math module, thruster control system, distribution and emergency integrated management, double closed loop control system, vessel static water resistance and dynamic software; instructor main control software. The monitor and control system is realized by real time data collection system and CAN bus technology. During the construction, most devices such as monitor panels and intelligent meters, are developed in lab which were based on embedded microcomputer system with CAN interface to link the network. They had also successfully used in practice and would be suitable for the future demands of digitalization ship.
Spacecraft-plasma-debris interaction in an ion beam shepherd mission
NASA Astrophysics Data System (ADS)
Cichocki, Filippo; Merino, Mario; Ahedo, Eduardo
2018-05-01
This paper presents a study of the interaction between a spacecraft, a plasma thruster plume and a free floating object, in the context of an active space debris removal mission based on the ion beam shepherd concept. The analysis is performed with the EP2PLUS hybrid code and includes the evaluation of the transferred force and torque to the target debris, its surface sputtering due to the impinging hypersonic ions, and the equivalent electric circuit of the spacecraft-plasma-debris interaction. The electric potential difference that builds up between the spacecraft and the debris, the ion backscattering and the backsputtering contamination of the shepherd satellite are evaluated for a nominal scenario. A sensitivity analysis is carried out to evaluate quantitatively the effects of electron thermodynamics, ambient plasma, heavy species collisions, and debris position.
Yamawaki, Hiroshi; Shimpuku, Mayumi; Sato, Hitomi; Wakabayashi, Taiga; Maruki, Yuuta; Kodaka, Yasuhiro; Nagoya, Hiroyuki; Shindo, Tomotaka; Kawagoe, Tetsuro; Sakamoto, Choitsu
2014-01-01
Background/Aims The association between clinical symptoms, gastric emptying, quality of life and sleep disorders in distinct functional dyspepsia (FD) patients has not been studied yet in detail. Methods We enrolled 79 FD patients (postprandial distress syndrome [PDS], n = 65; epigastric pain syndrome [EPS], n = 47; EPS-PDS overlap, n = 33) and 44 healthy volunteers. Gastric motility was evaluated. We used Rome III criteria to evaluate clinical symptoms and State-Trait Anxiety Inventory (STAI) scores to determine anxiety status. Sleep disorder was evaluated using the Pittsburgh Sleep Quality Index scores. Results There were no significant differences in age, sex and Helicobacter pylori positivity between FD subtypes and healthy volunteers. The scores of Glasgow dyspepsia severity scores (GDSS), SF-8 and Pittsburgh Sleep Quality Index (PSQI) in distinct subtypes of FD patients were significantly different from those in healthy volunteers. However, there were not significant differences in these scores, Tmax and T1/2 among 3 subtypes of FD patients. PSQI score was significantly (P = 0.027, P = 0.002 and P = 0.039, respectively) associated with GDSS among EPS, PDS and EPS-PDS overlap patients. In addition, 8-item short form health survey (SF-8; Physical Component Score and Mental Component Score) was significantly associated with global PSQI score in PDS and EPS-PDS overlap patients. In contrast, SF-8 (Mental Component Score) only was significantly linked to global PSQI score in EPS patients. Conclusions Prevalences for sleep disorders, gastric motility and quality of life in 3 subtypes of FD patients were similar levels. In PDS and EPS-PDS overlap patients, SF-8 was significantly associated with global PSQI score. PMID:24466451
Delineating the cell death mechanisms associated with skin electroporation.
Schultheis, Katherine; Smith, Trevor R F; Kiosses, William B; Kraynyak, Kimberly A; Wong, Amelia; Oh, Janet; Broderick, Kate Elizabeth
2018-06-28
The immune responses elicited following delivery of DNA vaccines to the skin has previously been shown to be significantly enhanced by the addition of electroporation (EP) to the treatment protocol. Principally, EP increases the transfection of pDNA into the resident skin cells. In addition to increasing the levels of in vivo transfection, the physical insult induced by EP is associated with activation of innate pathways which are believed to mediate an adjuvant effect, further enhancing DNA vaccine responses. Here, we have investigated the possible mechanisms associated with this adjuvant effect, primarily focusing on the cell death pathways associated with the skin EP procedure independent of pDNA delivery. Using the minimally invasive CELLECTRA®-3P intradermal electroporation device that penetrates the epidermal and dermal layers of the skin, we have investigated apoptotic and necrotic cell death in relation to the vicinity of the electrode needles and electric field generated. Employing the well-established TUNEL assay, we detected apoptosis beginning as early as one hour after EP and peaking at the 4 hour time point. The majority of the apoptotic events were detected in the epidermal region directly adjacent to the electrode needle. Using a novel propidium iodide in vivo necrotic cell death assay, we detected necrotic events concentrated in the epidermal region adjacent to the electrode. Furthermore, we detected up-regulation of calreticulin expression on skin cells after EP, thus labeling these cells for uptake by dendritic cells and macrophages. These results allow us to delineate the cell death mechanisms occurring in the skin following intradermal EP independently of pDNA delivery. We believe these events contribute to the adjuvant effect observed following electroporation at the skin treatment site.
The equivalence principle in a quantum world
NASA Astrophysics Data System (ADS)
Bjerrum-Bohr, N. E. J.; Donoghue, John F.; El-Menoufi, Basem Kamal; Holstein, Barry R.; Planté, Ludovic; Vanhove, Pierre
2015-09-01
We show how modern methods can be applied to quantum gravity at low energy. We test how quantum corrections challenge the classical framework behind the equivalence principle (EP), for instance through introduction of nonlocality from quantum physics, embodied in the uncertainty principle. When the energy is small, we now have the tools to address this conflict explicitly. Despite the violation of some classical concepts, the EP continues to provide the core of the quantum gravity framework through the symmetry — general coordinate invariance — that is used to organize the effective field theory (EFT).
Lalley-Chareczko, Linden; Clark, Devon; Conyngham, S Caitlin; Zuppa, Athena; Moorthy, Ganesh; Mounzer, Karam; Koenig, Helen
2018-06-12
Pre-exposure prophylaxis(PrEP) for HIV prevention with daily TDF/FTC is effective when taken consistently. Currently, there is no objective way to monitor PrEP adherence. Urine has been shown to be highly correlated with plasma tenofovir levels, with urine tenofovir levels >1000ng/mL demonstrating recent(1-2 days) adherence to PrEP. The present study was conducted at an urban community health center in Philadelphia, Pennsylvania. PrEP was administered to 50 young men who have sex with men and transgender women of color using weekly, biweekly, and/or monthly dispensation schedules. Primary objectives were retention at 48 weeks(in care at week 48 and completing ≥50% of medication pick-ups) and adherence assessed by urine tenofovir levels. Risk behaviors and sexually transmitted infections(STIs) diagnoses were also collected. 70% of participants were retained in care at 48 weeks. The proportion of subjects with urine tenofovir consistent with recent adherence was 80%, 74.4%, 82.4%, 82.4% and 69.7% at weeks 4, 12, 24, 36, and 48 respectively. 61 STIs were diagnosed over 231 screenings throughout 48 weeks, with no significant change between the first and second 24-week periods (p=0.43; 0 seroconversions). At week 48, more than half of subjects reported an increase or no change in condom use, an increase in their ability to discuss HIV with partners, and no change in number of sexual partners from baseline. These data demonstrate PrEP can be successfully delivered to a high-risk population with high program retention and medication adherence measured by urine tenofovir levels.
NASA Astrophysics Data System (ADS)
Rokicki, Ryszard; Haider, Waseem; Maffi, Shivani Kaushal
2015-01-01
Research was undertaken to determine the influence of the increased content of chromium in the outermost passive layer of magneto-electrochemically refined Co-Cr alloy L-605 surface on its hemocompatibility. The chemistry, roughness, surface energy, and wettability of conventionally electropolished (EP) and magnetoelectropolished (MEP) samples were studied with x-ray photoelectron spectroscopy (XPS), open circuit potential, atomic force microscopy, and contact angle meter. In vitro hemocompatibility of tested material surfaces was assessed using two important indicators of vascular responses to biomaterial, namely endothelialization and platelets adhesion. The endothelialization was assessed by seeding and incubating samples with human umbilical vein endothelial cells (HUVEC) for 3 days before counting and observing them under a fluorescent microscope. The platelet (rich plasma blood) adhesion and activation test on EP and MEP L-605 alloy surfaces was assessed using a laser scanning confocal microscope. The XPS analysis of MEP samples showed significant enrichment of the passive layer with Cr and O when compared with the EP one. The amount of other elements in the passive layer did not show a significant difference between EP and MEP treatments. The adhesion of HUVEC cells shows remarkable affinity to surfaces enriched in Cr (MEP) with almost 100% confluency. In addition, the number of platelets that adhered to standard EP surfaces was higher compared to the MEP surface. The present study shows that the chromium-enriched surface of cobalt-chromium alloy L-605 by the magnetoelectropolishing process tremendously improves surface hemocompatibility with regard to stent functionality by enhanced endothelialization and lower platelet adhesion and should be taken under consideration as an alternative surface of biodegradable polymer drug-eluting stents, polymer-free drug-eluting stents as well as bare-metal stents.
NASA Astrophysics Data System (ADS)
Obraztsov, S. M.; Konobeev, Yu. V.; Birzhevoy, G. A.; Rachkov, V. I.
2006-12-01
The dependence of mechanical properties of ferritic/martensitic (F/M) steels on irradiation temperature is of interest because these steels are used as structural materials for fast, fusion reactors and accelerator driven systems. Experimental data demonstrating temperature peaks in physical and mechanical properties of neutron irradiated pure iron, nickel, vanadium, and austenitic stainless steels are available in the literature. A lack of such an information for F/M steels forces one to apply a computational mathematical-statistical modeling methods. The bootstrap procedure is one of such methods that allows us to obtain the necessary statistical characteristics using only a sample of limited size. In the present work this procedure is used for modeling the frequency distribution histograms of ultimate strength temperature peaks in pure iron and Russian F/M steels EP-450 and EP-823. Results of fitting the sums of Lorentz or Gauss functions to the calculated distributions are presented. It is concluded that there are two temperature (at 360 and 390 °C) peaks of the ultimate strength in EP-450 steel and single peak at 390 °C in EP-823.
Influence of europium (Eu3+) ions on the optical properties of lithium zinc phosphate glasses
NASA Astrophysics Data System (ADS)
Shwetha, M.; Eraiah, B.
2018-02-01
Europium doped lithium zinc phosphate glasses with composition xEu2O3-(15-x) Li2O-45ZnO-40P2O5 (where x=0, 0.1, 0.3 and 0.5 mol %) named as EP0, EP1, EP3 and EP5 respectively, are prepared by melt-quenching method and the influence of Eu3+ ions on physical and optical properties of these glasses has been studied. Optical properties were studied using optical absorption spectra which was recorded at room temperature in the UV-Visible region. Optical direct band gap and indirect band gap energies were measured and their values range from 3.167 to 4.23eV and 2.08 to 3.02eV, respectively. Refractive indices have been measured with respect to different concentration of europium ions. Fluorescence spectroscopy measurements have been performed by excitation in the UV-Visible range, which resulted in the significant fluorescence peaks. The luminescence color of the glass system is characterized using Commission International de l’Eclairage de France 1931 standards.
PR2EPS: Preparation, Recruitment, Retention and Excellence in the Physical Sciences
NASA Astrophysics Data System (ADS)
Schaumloffel, John; Gallagher, Hugh; Miller, Jeremy; Labroo, Sunil; Bischoff, Paul
2004-03-01
PR2EPS, is an NSF-DUE sponsored program at SUNY Oneonta designed to attract students to study physics, chemistry and related physical science disciplines at SUNY Oneonta. The program also seeks to increase the retention rate for all students in these disciplines by providing specialized skill-building and professional development courses, an evening tutoring center, and exposure to research and professional activities during the students first three-years of undergraduate study. A key focus of the project is drawing students from the five, primarily rural and agricultural, counties surrounding Oneonta, NY. Their first direct exposure to the program will be in recruiting visits to local high schools where promising candidates will be invited to participate in a weeklong summer camp designed to demonstrate to them that they possess the requisite skills and potential to succeed in these technically demanding disciplines. A description of the program, including the collaboration of faculty from the Departments of Physics & Astronomy, Chemistry & Biochemistry, Education and as well as the initial outcomes of the tutoring center and local outreach will be presented.
Levitt, N C; Propper, D J; Madhusudan, S; Braybrooke, J P; Echeta, C; te Poele, R; Davies, S L; Flanagan, E; Hickson, I D; Joel, S; Ganesan, T S
2005-01-01
A pharmacokinetically guided phase I study of topotecan and etoposide phosphate was conducted in recurrent ovarian cancer. The scheduling of the topoisomerase I and II inhibitors was determined using in vitro activity data. All patients had recurrent disease following prior platinum-containing chemotherapy. Patients had a World Health Organisation performance status of 0–2 and adequate bone marrow, renal and hepatic function. Treatment was with topotecan intravenously for 5 days followed immediately by a 5-day intravenous infusion of etoposide phosphate (EP), with pharmacokinetically guided dose adjustment. Plasma etoposide levels were measured on days 2 and 4 of the infusion. A total of 21 patients entered the study. In all, 48% were platinum resistant and 71% had received prior paclitaxel. The main toxicities were haematological, short lived and reversible. A total of 29% of patients experienced grade 4 thrombocytopenia and 66% grade 4 neutropenia after the first cycle. Neutropenia and thrombocytopenia was dose limiting. The maximum-tolerated dose was topotecan 0.85 mg m−2 day−1 days 1–5 followed immediately by a 5-day infusion of EP at a plasma concentration of 1 μg ml−1. The response rate (RR) was 28% in 18 evaluable patients. There was marked interpatient variability in topoisomerase IIα levels measured from peripheral lymphocytes, with no observed increase following topotecan. This regimen of topotecan followed by EP demonstrated good activity in recurrent ovarian cancer and was noncrossresistant with paclitaxel. Both the toxicity and RR was higher than would be expected from the single agent data, in keeping with synergy of action. PMID:15956976
NASA Astrophysics Data System (ADS)
Lin, Yung-Hsu
The goal of this dissertation is to study high pressure streamers in air and apply it to diesel engine technologies. Nanosecond scale pulsed high voltage discharges in air/fuel mixtures can generate radicals which in turn have been shown to improve combustion efficiency in gasoline fueled internal combustion engines. We are exploring the possibility to extend such transient plasma generation and expected radical species generation to the range of pressures encountered in compression-ignition (diesel) engines having compression ratios of ˜20:1, thereby improving lean burning efficiency and extending the range of lean combustion. At the beginning of this dissertation, research into streamer discharges is reviewed. Then, we conducted experiments of streamer propagation at high pressures, calculated the streamer velocity based on both optical and electrical measurements, and the similarity law was checked by analyzing the streamer velocity as a function of the reduced electric field, E/P. Our results showed that the similarity law is invalid, and an empirical scaling factor, E/√P, is obtained and verified by dimensional analysis. The equation derived from the dimensional analysis will be beneficial to proper electrode and pulse generator design for transient plasma assisted internal engine experiments. Along with the high pressure study, we applied such technique on diesel engine to improve the fuel efficiency and exhaust treatment. We observed a small effect of transient plasma on peak pressure, which implied that transient plasma has the capability to improve the fuel consumption. In addition, the NO can be reduced effectively by the same technique and the energy cost is 30 eV per NO molecule.
García, José Miguel; García, Vanesa; Peña, Cristina; Domínguez, Gemma; Silva, Javier; Diaz, Raquel; Espinosa, Pablo; Citores, Maria Jesús; Collado, Manuel; Bonilla, Félix
2008-01-01
Little is yet known about the origin and protective mechanism of free nucleic acids in plasma. We investigated the possibility of these free nucleic acids being particle associated. Plasma samples from colon cancer patients and cell culture media were subjected to various antibody incubations, ultracentrifugation, and RNA extraction protocols for total RNA, epithelial RNA, and mRNA. Flow cytometry using a Ber-EP4 antibody and confocal laser microscopy after staining with propidium iodide were also performed. mRNA levels of the LISCH7 and SDHA genes were determined in cells and in culture media. Ber-EP4 antibody and polystyrene beads coated with oligo dT sequences were employed. We observed that, after incubation, total RNA and mRNA were always detected after membrane digestion, and that epithelial RNA was detected before this procedure. In ultracentrifugation, mRNA was caught in the supernatant only if a former lysis mediated or in the pellet if there was no previous digestion. Flow cytometry determinations showed that antibody-coated microbeads keep acellular structures bearing epithelial antigens apart. Confocal laser microscopy made 1- to 2-μm-diameter particles perceptible in the vicinity of magnetic polystyrene beads. Relevant differences were observed between mRNA of cells and culture media, as there was a considerable difference in LISCH7 mRNA levels between HT29 and IMR90 cell co-cultures and their culture media. Our results support the view that extracellular RNA found in plasma from cancer patients circulates in association with or is protected in a multiparticle complex, and that an active release mechanism by tumor cells may be a possible origin. PMID:18456845
Vito, Virgina De; Saba, Alessandro; Lee, Hong-Ki; Owen, Helen; Poapolathep, Amnart; Giorgi, Mario
2016-01-25
Grapiprant, a novel pharmacologically active ingredient, acts as a selective EP4 receptor antagonist whose physiological ligand is prostaglandin E2 (PGE2). It is currently under development for use in humans and dogs for the control of pain and inflammation associated with osteoarthritis. The aim of the present study was to develop an easy and sensitive method to quantify grapiprant in canine plasma and to apply the method in a canine patient. Several parameters, both in the extraction and detection method were evaluated. The final mobile phase consisted of ACN:AcONH4 (20 mM) solution, pH 4 (70:30, v/v) at a flow rate of 1 mL/min. The elution of grapiprant and IS (metoclopramide) was carried out in isocratic mode through a Synergi Polar-RP 80A analytical column (150 mm × 4.6 mm). The best excitation and emission wavelengths were 320 and 365 nm, respectively. Grapiprant was extracted from the plasma using CHCl3, which gave a recovery of 88.1 ± 10.22% and a lower limit of quantification (LLOQ) of 10 ng/mL. The method was validated in terms of linearity, limit of detection (LOD), LLOQ, selectivity, accuracy and precision, extraction recovery, stability, and inter-laboratory cross validation, according to international guidelines. The chromatographic runs were specific with no interfering peaks at the retention times of the analyte and IS, as confirmed by HPLC-MS experiments. In conclusion, this was a simple and effective method using HPLC-FL to detect grapiprant in plasma, which may be useful for future pharmacokinetic studies. Copyright © 2015 Elsevier B.V. All rights reserved.
INTEGRAL BENCHMARK DATA FOR NUCLEAR DATA TESTING THROUGH THE ICSBEP AND THE NEWLY ORGANIZED IRPHEP
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Blair Briggs; Lori Scott; Yolanda Rugama
The status of the International Criticality Safety Benchmark Evaluation Project (ICSBEP) was last reported in a nuclear data conference at the International Conference on Nuclear Data for Science and Technology, ND-2004, in Santa Fe, New Mexico. Since that time the number and type of integral benchmarks have increased significantly. Included in the ICSBEP Handbook are criticality-alarm / shielding and fundamental physic benchmarks in addition to the traditional critical / subcritical benchmark data. Since ND 2004, a reactor physics counterpart to the ICSBEP, the International Reactor Physics Experiment Evaluation Project (IRPhEP) was initiated. The IRPhEP is patterned after the ICSBEP, butmore » focuses on other integral measurements, such as buckling, spectral characteristics, reactivity effects, reactivity coefficients, kinetics measurements, reaction-rate and power distributions, nuclide compositions, and other miscellaneous-type measurements in addition to the critical configuration. The status of these two projects is discussed and selected benchmarks highlighted in this paper.« less
A hadronic origin for ultra-high-frequency-peaked BL Lac objects
NASA Astrophysics Data System (ADS)
Cerruti, M.; Zech, A.; Boisson, C.; Inoue, S.
2015-03-01
Current Cherenkov telescopes have identified a population of ultra-high-frequency peaked BL Lac objects (UHBLs), also known as extreme blazars, that exhibit exceptionally hard TeV spectra, including 1ES 0229+200, 1ES 0347-121, RGB J0710+591, 1ES 1101-232, and 1ES 1218+304. Although one-zone synchrotron-self-Compton (SSC) models have been generally successful in interpreting the high-energy emission observed in other BL Lac objects, they are problematic for UHBLs, necessitating very large Doppler factors and/or extremely high minimum Lorentz factors of the emitting leptonic population. In this context, we have investigated alternative scenarios where hadronic emission processes are important, using a newly developed (lepto-)hadronic numerical code to systematically explore the physical parameters of the emission region that reproduces the observed spectra while avoiding the extreme values encountered in pure SSC models. Assuming a fixed Doppler factor δ = 30, two principal parameter regimes are identified, where the high-energy emission is due to: (1) proton-synchrotron radiation, with magnetic fields B ˜ 1-100 G and maximum proton energies Ep; max ≲ 1019 eV; and (2) synchrotron emission from p-γ-induced cascades as well as SSC emission from primary leptons, with B ˜ 0.1-1 G and Ep; max ≲ 1017 eV. This can be realized with plausible, sub-Eddington values for the total (kinetic plus magnetic) power of the emitting plasma, in contrast to hadronic interpretations for other blazar classes that often warrant highly super-Eddington values.
Zhou, Xia; Qiu, Shuilai; Xing, Weiyi; Gangireddy, Chandra Sekhar Reddy; Gui, Zhou; Hu, Yuan
2017-08-30
A novel polyphosphazene (PZS) microsphere@molybdenum disulfide nanoflower (MoS 2 ) hierarchical hybrid architecture was first synthesized and applied for enhancing the mechanical performance and flame retardancy of epoxy (EP) resin via a cooperative effect. Herein, using PZS microsphere as the template, a layer of MoS 2 nanoflowers were anchored to PZS spheres via a hydrothermal strategy. The well-designed PZS@MoS 2 exhibits excellent fire retardancy and a reinforcing effect. The obtained PZS@MoS 2 significantly enhanced the flame-retardant performance of EP composites, which can be proved by thermogravimetric and cone calorimeter results. For instance, the incorporation of 3 wt % PZS@MoS 2 brought about a 41.3% maximum reduction in the peak heat-release rate and decreased by 30.3% maximum in the total heat release, accompanying the higher graphitized char layer. With regard to mechanical property, the storage modulus of EP/PZS@MoS 2 3.0 in the glassy state was dramatically increased to 22.4 GPa in comparison with that of pure EP (11.15 GPa). It is sensible to know that the improved flame-retardant performance for EP composites is primarily assigned to a physical barrier effect of the MoS 2 nanoflowers and the polyphosphazene structure has an positive impact on promoting char formation in the condensed phase.
Fish, K; Osborn, A M; Boxall, J B
2017-09-01
High-quality drinking water from treatment works is degraded during transport to customer taps through the Drinking Water Distribution System (DWDS). Interactions occurring at the pipe wall-water interface are central to this degradation and are often dominated by complex microbial biofilms that are not well understood. This study uses novel application of confocal microscopy techniques to quantify the composition of extracellular polymeric substances (EPS) and cells of DWDS biofilms together with concurrent evaluation of the bacterial community. An internationally unique, full-scale, experimental DWDS facility was used to investigate the impact of three different hydraulic patterns upon biofilms and subsequently assess their response to increases in shear stress, linking biofilms to water quality impacts such as discolouration. Greater flow variation during growth was associated with increased cell quantity but was inversely related to EPS-to-cell volume ratios and bacterial diversity. Discolouration was caused and EPS was mobilised during flushing of all conditions. Ultimately, biofilms developed under low-varied flow conditions had lowest amounts of biomass, the greatest EPS volumes per cell and the lowest discolouration response. This research shows that the interactions between hydraulics and biofilm physical and community structures are complex but critical to managing biofilms within ageing DWDS infrastructure to limit water quality degradation and protect public health. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
Xiang, Yu-Tao; Weng, Yong-Zhen; Leung, Chi-Ming; Tang, Wai-Kwong; Ungvari, Gabor S
2008-02-01
This study compared the subjective quality of life (SQOL) in schizophrenia patients living with their families in Hong Kong (HK) and Beijing (BJ) and explored the relationship between SQOL and basic socio-demographic and clinical factors. Two hundred and sixty-four clinically stable outpatients with schizophrenia were randomly selected in HK and 258 counterparts matched according to age, sex, age at onset, and length of illness in BJ. SQOL and psychiatric status were assessed with standard rating instruments. There was no significant difference in any of SQOL domains between the two cohorts after controlling for potentially confounding variables. Positive, depressive and anxiety symptoms and drug-induced extrapyramidal side effects (EPS) were all significantly correlated with SQOL. Multiple regression analysis revealed that only depressive symptoms predicted all SQOL domains in both groups. Having removed depressive symptoms from the model, positive symptoms predicted all domains, anxiety predicted all but social domains, use of benzodiazepines (BZD) predicted all but physical domains, EPS predicted physical domain, and history of suicide predicted social domain in HK; anxiety predicted all domains, positive symptoms predicted all but physical domains, EPS, use of BZD and history of suicide all predicted physical domains, and length of illness predicted environmental domain in BJ. Despite considerable differences between the two sites in terms of health care delivery and the economic conditions of the subjects, SQOL did not differ between HK and BJ. The conclusion is in line with previous studies that suggested that patients' SQOL was independent of their living standard as long as it reached a certain minimum level. SQOL was more strongly related to the severity of depressive symptoms and had weak association with socio-demographic factors.
Boroumandfar, Khadijeh; Javaheri, Shabnam; Ehsanpour, Soheila; Abedi, Ahmad
2010-01-01
BACKGROUND: Domestic violence (DV) is a serious problem all over the world which had been extended to boundaries of countries, economical, cultural and racial classes. 10-69 percent of women are exposed to physical, sexual and emotional violence which has numerous physical and emotional consequences. Therefore, males’ attitude towards women is one of the strongest predicting factors of violence against women, so one of the ways to remove the violence against women is to change the men's attitude. Changing the attitude, in the basic stages of the marriage for couples who are not yet involved with marital misunderstandings, will probably influence their future relationships, therefore, the present study reviewed two attitude changing methods of educational package (EP) and social inoculation (SI) which were used to change the attitude among male volunteers participating in the premarital counseling classes. METHODS: This was a semi-experimental study aimed to determine the influence of two methods of supplying EP and SI on the change of attitude toward DV against women. The study subjects included male volunteers participating in Isfahan Molla Hadi Sabzevari Premarital Counseling Center, where the attitudes of 183 subjects were investigated primarily using simple sampling method. Ninety-nine subjects who had positive attitude toward DV were selected and then, randomly distributed into three 33-subject groups. The first was SI group, the second was EP supply group and the third was the control group. Data collection tool was an evaluating questionnaire of the attitude toward DV against women which consisted of two parts, demographic data and 34 attitude evaluating questions. Scientific validity was determined by content validity method and scientific reliability was determined using Cronbach's alpha. Analyzing the data was done using descriptive (frequency and mean), analytical statistical methods (paired-t, independent t-tests, ANOVA, Duncan, Kruskal-Wallis and chi-square) and SPSS software. RESULTS: Among 183 participants, 99 of them (54%) had a positive attitude with an average score of 46.5 and 84 of them (45%) with an average score of 29 had a negative attitude toward violence against women. Before the intervention, the highest violence attitude was in emotional, physical and sexual areas, respectively. After the intervention in the inoculation group, the highest attitude changes were in physical, sexual and emotional areas, respectively and in the EP group, in total the attitude changes score after the intervention was significant compared to prior to it, although changes were observed only in physical and sexual areas. In SI group, more attitude changes were occurred than that in EP group. In control group, the attitude score after the intervention had no significant change compared to it before. CONCLUSIONS: Although attitude change has no guaranty for changing the behavior, in order to change the behavior, changing the attitude is required, in which for violence against women, it is better to be started at the beginning of the marital relationship. The SI method has been successfully applied in psychology Sciences and the health programs, but the EP method is not an effective method on its own to change the attitude, so it is better to be accompanied by other methods like group discussion, etc. PMID:22069401
NASA Astrophysics Data System (ADS)
Shoucri, Magdi; Charbonneau-Lefort, Mathieu; Afeyan, Bedros
2008-11-01
We study the interaction of a high intensity laser with an overdense plasma. When the intensity of the laser is sufficiently high to make the electrons relativistic, unusual interactions between the EM wave and the surface of the plasma take place. We use an Eulerian Vlasov code for the numerical solution of the one-dimensional two-species relativistic Vlasov-Maxwell equations [1]. The results show that the incident laser steepens the density profile significantly. There is a large build-up of electron density at the plasma edge, and as a consequence a large charge separation that is induced under the action of the intense laser field. This results in an intense quasistatic longitudinal electric field generated at the surface of the plasma which accelerates ions in the forward direction. We will show the details of the formation of the longitudinal edge electric field and of electron and ion phase-space structures. [1] M. Charbonneau-Lefort, M. Shoucri, B. Afeyan , Proc. of the EPS Conference, Greece (2008).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, W.H.
1997-06-01
These lectures describe QCD physics studies over the period 1992--1996 from data taken with collisions of 27 GeV electrons and positrons with 820 GeV protons at the HERA collider at DESY by the two general-purpose detectors H1 and ZEUS. The focus of these lectures is on structure functions and jet production in deep inelastic scattering, photoproduction, and diffraction. The topics covered start with a general introduction to HERA and ep scattering. Structure functions are discussed. This includes the parton model, scaling violation, and the extraction of F{sub 2}, which is used to determine the gluon momentum distribution. Both low andmore » high Q{sup 2} regimes are discussed. The low Q{sup 2} transition from perturbative QCD to soft hadronic physics is examined. Jet production in deep inelastic scattering to measure {alpha}{sub s}, and in photoproduction to study resolved and direct photoproduction, is also presented. This is followed by a discussion of diffraction that begins with a general introduction to diffraction in hadronic collisions and its relation to ep collisions, and moves on to deep inelastic scattering, where the structure of diffractive exchange is studied, and in photoproduction, where dijet production provides insights into the structure of the Pomeron. 95 refs., 39 figs.« less
NASA Technical Reports Server (NTRS)
Polzin, Kurt A.; Hill, Carrie S.
2013-01-01
Inductive magnetic field probes (also known as B-dot probes and sometimes as B-probes or magnetic probes) are useful for performing measurements in electric space thrusters and various plasma accelerator applications where a time-varying magnetic field is present. Magnetic field probes have proven to be a mainstay in diagnosing plasma thrusters where changes occur rapidly with respect to time, providing the means to measure the magnetic fields produced by time-varying currents and even an indirect measure of the plasma current density through the application of Ampère's law. Examples of applications where this measurement technique has been employed include pulsed plasma thrusters and quasi-steady magnetoplasmadynamic thrusters. The Electric Propulsion Technical Committee (EPTC) of the American Institute of Aeronautics and Astronautics (AIAA) was asked to assemble a Committee on Standards (CoS) for Electric Propulsion Testing. The assembled CoS was tasked with developing Standards and Recommended Practices for various diagnostic techniques used in the evaluation of plasma thrusters. These include measurements that can yield either global information related to a thruster and its performance or detailed, local data related to the specific physical processes occurring in the plasma. This paper presents a summary of the standard, describing the preferred methods for fabrication, calibration, and usage of inductive magnetic field probes for use in diagnosing plasma thrusters. Inductive magnetic field probes (also called B-dot probes throughout this document) are commonly used in electric propulsion (EP) research and testing to measure unsteady magnetic fields produced by time-varying currents. The B-dot probe is relatively simple in construction, and requires minimal cost, making it a low-cost technique that is readily accessible to most researchers. While relatively simple, the design of a B-dot probe is not trivial and there are many opportunities for errors in probe construction, calibration, and usage, and in the post-processing of data that is produced by the probe. There are typically several ways in which each of these steps can be approached, and different applications may require more or less vigorous attention to various issues.
A review of progress in the physics of open quantum systems: theory and experiment.
Rotter, I; Bird, J P
2015-11-01
This report on progress explores recent advances in our theoretical and experimental understanding of the physics of open quantum systems (OQSs). The study of such systems represents a core problem in modern physics that has evolved to assume an unprecedented interdisciplinary character. OQSs consist of some localized, microscopic, region that is coupled to an external environment by means of an appropriate interaction. Examples of such systems may be found in numerous areas of physics, including atomic and nuclear physics, photonics, biophysics, and mesoscopic physics. It is the latter area that provides the main focus of this review, an emphasis that is driven by the capacity that exists to subject mesoscopic devices to unprecedented control. We thus provide a detailed discussion of the behavior of mesoscopic devices (and other OQSs) in terms of the projection-operator formalism, according to which the system under study is considered to be comprised of a localized region (Q), embedded into a well-defined environment (P) of scattering wavefunctions (with Q + P = 1). The Q subspace must be treated using the concepts of non-Hermitian physics, and of particular interest here is: the capacity of the environment to mediate a coupling between the different states of Q; the role played by the presence of exceptional points (EPs) in the spectra of OQSs; the influence of EPs on the rigidity of the wavefunction phases, and; the ability of EPs to initiate a dynamical phase transition (DPT). EPs are singular points in the continuum, at which two resonance states coalesce, that is where they exhibit a non-avoided crossing. DPTs occur when the quantum dynamics of the open system causes transitions between non-analytically connected states, as a function of some external control parameter. Much like conventional phase transitions, the behavior of the system on one side of the DPT does not serve as a reliable indicator of that on the other. In addition to discussing experiments on mesoscopic quantum point contacts that provide evidence of the environmentally-mediated coupling of quantum states, we also review manifestations of DPTs in mesoscopic devices and other systems. These experiments include observations of resonance-trapping behavior in microwave cavities and open quantum dots, phase lapses in tunneling through single-electron transistors, and spin swapping in atomic ensembles. Other possible manifestations of this phenomenon are presented, including various superradiant phenomena in low-dimensional semiconductors. From these discussions a generic picture of OQSs emerges in which the environmentally-mediated coupling between different quantum states plays a critical role in governing the system behavior. The ability to control or manipulate this interaction may even lead to new applications in photonics and electronics.
O'Brien, Myles W; Shields, Christopher A; Oh, Paul I; Fowles, Jonathon R
2017-04-01
The Exercise is Medicine Canada (EIMC) initiative promotes physical activity counselling and exercise prescription within health care. The purpose of this study was to evaluate perceptions and practices around physical activity counselling and exercise prescription in health care professionals before and after EIMC training. Prior to and directly following EIMC workshops, 209 participants (physicians (n = 113); allied health professionals (AHPs) (n = 54), including primarily nurses (n = 36) and others; and exercise professionals (EPs) (n = 23), including kinesiologists (n = 16), physiotherapists (n = 5), and personal trainers (n = 2)) from 7 provinces completed self-reflection questionnaires. Compared with AHPs, physicians saw more patients (78% > 15 patients/day vs 93% < 15 patients/day; p < 0.001) and reported lower frequencies of exercise counselling during routine client encounters (48% vs 72% in most sessions; p < 0.001). EPs had higher confidence providing physical activity information (92 ± 11%) compared with both physicians (52 ± 25%; p < 0.001) and AHPs (56 ± 24%; p < 0.001). Physicians indicated that they experienced greater difficulty including physical activity and exercise counselling into sessions (2.74 ± 0.71, out of 5) compared with AHPs (2.17 ± 0.94; p = 0.001) and EPs (1.43 ± 0.66; p < 0.001). Physicians rated the most impactful barriers to exercise prescription as lack of patient interest (2.77 ± 0.85 out of 4), resources (2.65 ± 0.82 out of 4), and time (2.62 ± 0.71 out of 4). The majority of physicians (85%) provided a written prescription for exercise in <10% of appointments. Following the workshop, 87% of physician attendees proposed at least one change to practice; 47% intended on changing their practice by prescribing exercise routinely, and 33% planned on increasing physical activity and exercise counselling, measured through open-ended responses.
Microbial Activity and Depositional System Dynamics: Linking Scales With The Aid of New Technology
NASA Astrophysics Data System (ADS)
Defew, E. C.; Hagerthey, S. E.; Honeywill, C.; Perkins, R. G.; Black, K. S.; Paterson, D. M.
The dynamics of estuarine depositional systems are influenced by sediment-dwelling microphytobenthic assemblages. These assemblages produce extracellular polymeric substances (EPS), which are known to be important in the process of sediment biosta- bilisation. However, these communities are generally studied on very small spatial scales making the prediction of primary productivity and their importance in terms of sediment stability over large areas uncertain. Recent advances in our knowledge of the biostabilisation process have allowed the establishment of links between EPS produc- tion, spatial distribution of algal biomass and their primary productivity over much larger spatial scales. For example, during the multidisciplinary BIOPTIS project, re- mote sensing (RS) was combined with ground-truthing measurements of physical and biological parameters to produce synoptic maps leading to a better understanding of system dynamics and the potential effects of environmental perturbations such as cli- mate change. Recent work using low-temperature scanning electron microscopy (LT- SEM) and in-line laser holography has measured the influence of EPS on the erosional behaviour of sediment flocs and particles and has shown that an increase in the con- centration of EPS determines the nature of the eroded floc material and the critical threshold for sediment erosion. This provides the mechanistic link required between EPS concentration and sediment stability. Whilst it is not yet possible to discern EPS concentration directly by RS studies, we know that EPS concentrations in sediments co-vary with chlorophyll a content, and are closely related to algal productivity. There- fore, RS studies which provide large-scale spatial information of chlorophyll a distri- bution may be used to model the stability and productivity of intertidal depositional systems. This paper introduces the basis of these linkages from the cellular level (in situ chlorophyll fluorescence), the ground-truthing approach (sediment stability, struc- ture, pigment distribution, in situ chlorophyll fluorescence) and investigates the poten- tial of a RS approach in a case study of a Scottish Estuary.
Novakova, Barbora; Howlett, Stephanie; Baker, Roger; Reuber, Markus
2015-07-01
This exploratory study aimed to examine emotion-processing styles in patients with psychogenic non-epileptic seizures (PNES), compared to healthy individuals, and to explore associations of emotion processing with other psychological measures and seizure frequency, using the new Emotional Processing Scale (EPS-25), which had not previously been used in this patient group. Fifty consecutive patients with PNES referred for psychotherapy completed a set of self-report questionnaires, including the Emotional Processing Scale (EPS-25), Clinical Outcome in Routine Evaluation (CORE-10), Short Form-36 (SF-36), Patient Health Questionnaire (PHQ-15), and Brief Illness Perception Questionnaire (BIPQ). Responses on the EPS-25 were compared to data from 224 healthy controls. Patients with PNES had greater emotion processing deficits across all dimensions of the EPS-25 than healthy individuals (suppression/unprocessed emotion/unregulated emotion/avoidance/impoverished emotional experience). Impaired emotion processing was highly correlated with psychological distress, more frequent and severe somatic symptoms, and a more threatening understanding of the symptoms. Emotion processing problems were also associated with reduced health-related quality of life on the mental health (but not the physical health) component of the SF-36. The unregulated emotions sub-scale of the EPS was associated with lower seizure frequency. The results showed clear impairments of emotion processing in patients with PNES compared to healthy individuals, which were associated with greater psychological distress and reduced mental health functioning. These findings seem to support the face validity of the EPS-25 as a measure for PNES patients and its potential as a tool to assess the effectiveness of psychological interventions. Copyright © 2015 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.
Saturation of energetic-particle-driven geodesic acoustic modes due to wave-particle nonlinearity
NASA Astrophysics Data System (ADS)
Biancalani, A.; Chavdarovski, I.; Qiu, Z.; Bottino, A.; Del Sarto, D.; Ghizzo, A.; Gürcan, Ö.; Morel, P.; Novikau, I.
2017-12-01
The nonlinear dynamics of energetic-particle (EP) driven geodesic acoustic modes (EGAM) is investigated here. A numerical analysis with the global gyrokinetic particle-in-cell code ORB5 is performed, and the results are interpreted with the analytical theory, in close comparison with the theory of the beam-plasma instability. Only axisymmetric modes are considered, with a nonlinear dynamics determined by wave-particle interaction. Quadratic scalings of the saturated electric field with respect to the linear growth rate are found for the case of interest. As a main result, the formula for the saturation level is provided. Near the saturation, we observe a transition from adiabatic to non-adiabatic dynamics, i.e. the frequency chirping rate becomes comparable to the resonant EP bounce frequency. The numerical analysis is performed here with electrostatic simulations with circular flux surfaces, and kinetic effects of the electrons are neglected.
Nonlinear evolution of energetic-particles-driven waves in collisionless plasmas
NASA Astrophysics Data System (ADS)
Li, Shuhan; Liu, Jinyuan; Wang, Feng; Shen, Wei; Li, Dong
2018-06-01
A one-dimensional electrostatic collisionless particle-in-cell code has been developed to study the nonlinear interaction between electrostatic waves and energetic particles (EPs). For a single wave, the results are clear and agree well with the existing theories. For coexisting two waves, although the mode nonlinear coupling between two wave fields is ignored, the second-order phase space islands can still exist between first-order islands generated by the two waves. However, the second-order phase islands are not formed by the superposed wave fields and the perturbed motions of EPs induced by the combined effect of two main resonances make these structures in phase space. Owing to these second-order islands, energy can be transferred between waves, even if the overlap of two main resonances never occurs. Depending on the distance between the main resonance islands in velocity space, the second-order island can affect the nonlinear dynamics and saturations of waves.
Discharge start-up and ramp-up development for NSTX-U and MAST-U
NASA Astrophysics Data System (ADS)
Battaglia, D. J.; Boyer, M. D.; Gerhardt, S. P.; Menard, J. E.; Mueller, D.; Cunningham, G.; Kirk, A.; Kogan, L.; McArdle, G.; Pangione, L.; Thornton, A. J.; Ren, E.
2017-10-01
A collaborative modeling effort is underway to develop robust inductive start-up and ramp-up scenarios for NSTX-U and MAST-U. These complementary spherical tokamak devices aim to generate the physics basis for achieving steady-state, high-beta and high-confinement plasma discharges with a self-consistent solution for managing the divertor heat flux. High-performance discharges in these devices require sufficient plasma elongation (κ = 2.4 - 2.8) to maximize the bootstrap and beam-driven current drive, increase MHD stability at high Ip and high βN, and realize advanced divertor geometries such as the snowflake and super-X. Achieving the target elongation on NSTX-U is enabled by an L-H transition in the current ramp-up that slows the current diffusion and maintains a low internal inductance (li <= 0.8). Modeling focuses on developing scenarios that achieve a suitable field null for breakdown and discharge conditions conducive to an early L-H transition while maintaining vertical and MHD stability, with appropriate margin for variation in experimental conditions. The toroidal currents induced in conducting structures and the specifications of the real-time control and power supply systems are unique constraints for the two devices. Work Supported by U.S. DOE Contract No. DE-AC02-09CH11466 and the RCUK Energy Programme [Grant Number EP/P012450/1].
NASA Astrophysics Data System (ADS)
2001-09-01
EPS AWARD WINNERS Award for outreach to Physics Education authors; TEACHER TRAINING Helping teachers specialize in physics; AAPT SUMMER MEETING The science of light; AAPT SUMMER MEETING Do you believe in skepticism?; E-LEARNING Massive investment in Swedish online learning; UK SCIENCE YEAR News from Science Year; 11-16 CURRICULUM Naming the energy parts; TEACHER TRAINING Electronic Discussion Group for Trainee Teachers; PUBLICATIONS Physics on Course 2002; WALES Physics in Powys; HIGHER EDUCATION HE solutions to the physics teacher shortage; SCOTLAND The 27th Scottish Stirling Meeting; NORTHERN IRELAND Belfast physics teachers' meeting; SCOTLAND Physics Summer School, Edinburgh 2001; AAPT SUMMER MEETING Physics education research: massive growth; AAPT SUMMER MEETING Just-In-Time Teaching;
GROWTH OF THE INTERNATIONAL CRITICALITY SAFETY AND REACTOR PHYSICS EXPERIMENT EVALUATION PROJECTS
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Blair Briggs; John D. Bess; Jim Gulliford
2011-09-01
Since the International Conference on Nuclear Criticality Safety (ICNC) 2007, the International Criticality Safety Benchmark Evaluation Project (ICSBEP) and the International Reactor Physics Experiment Evaluation Project (IRPhEP) have continued to expand their efforts and broaden their scope. Eighteen countries participated on the ICSBEP in 2007. Now, there are 20, with recent contributions from Sweden and Argentina. The IRPhEP has also expanded from eight contributing countries in 2007 to 16 in 2011. Since ICNC 2007, the contents of the 'International Handbook of Evaluated Criticality Safety Benchmark Experiments1' have increased from 442 evaluations (38000 pages), containing benchmark specifications for 3955 critical ormore » subcritical configurations to 516 evaluations (nearly 55000 pages), containing benchmark specifications for 4405 critical or subcritical configurations in the 2010 Edition of the ICSBEP Handbook. The contents of the Handbook have also increased from 21 to 24 criticality-alarm-placement/shielding configurations with multiple dose points for each, and from 20 to 200 configurations categorized as fundamental physics measurements relevant to criticality safety applications. Approximately 25 new evaluations and 150 additional configurations are expected to be added to the 2011 edition of the Handbook. Since ICNC 2007, the contents of the 'International Handbook of Evaluated Reactor Physics Benchmark Experiments2' have increased from 16 different experimental series that were performed at 12 different reactor facilities to 53 experimental series that were performed at 30 different reactor facilities in the 2011 edition of the Handbook. Considerable effort has also been made to improve the functionality of the searchable database, DICE (Database for the International Criticality Benchmark Evaluation Project) and verify the accuracy of the data contained therein. DICE will be discussed in separate papers at ICNC 2011. The status of the ICSBEP and the IRPhEP will be discussed in the full paper, selected benchmarks that have been added to the ICSBEP Handbook will be highlighted, and a preview of the new benchmarks that will appear in the September 2011 edition of the Handbook will be provided. Accomplishments of the IRPhEP will also be highlighted and the future of both projects will be discussed. REFERENCES (1) International Handbook of Evaluated Criticality Safety Benchmark Experiments, NEA/NSC/DOC(95)03/I-IX, Organisation for Economic Co-operation and Development-Nuclear Energy Agency (OECD-NEA), September 2010 Edition, ISBN 978-92-64-99140-8. (2) International Handbook of Evaluated Reactor Physics Benchmark Experiments, NEA/NSC/DOC(2006)1, Organisation for Economic Co-operation and Development-Nuclear Energy Agency (OECD-NEA), March 2011 Edition, ISBN 978-92-64-99141-5.« less
Huang, Zhenzhen; Xu, Piao; Chen, Guiqiu; Zeng, Guangming; Chen, Anwei; Song, Zhongxian; He, Kai; Yuan, Lei; Li, Hui; Hu, Liang
2018-04-01
This study investigated the influence of silver ions (Ag + ) on the cytotoxicity of silver nanoparticles (AgNPs) in Phanerochaete chrysosporium and noted the degree of extracellular secretions in response to the toxicant's stress. Oxalate production was elicited with moderate concentrations of 2,4-dichlorophenol (2,4-DCP) and AgNPs reaching a plateau at 10 mg/L and 10 μM, respectively. Increased oxalate accumulation was accompanied by higher activities of manganese peroxidase (MnP) and lignin peroxidase (LiP). However, the secretion of oxalate, MnP and LiP was significantly inhibited owing to Ag + incorporation into AgNP solution. Production of extracellular polymeric substances (EPS) significantly elevated with an increase in 2,4-DCP concentrations; however, after 24 h of exposure to 100 mg/L 2,4-DCP, an obvious decrease in EPS occurred, indicating that part of EPS could be consumed as carbon and energy sources to ameliorate biological tolerance to toxic stress. Furthermore, AgNP-induced "particle-specific" cytotoxicity was substantially enhanced with additional Ag + as evidenced by its significant negative impact on cellular growth, plasma membrane integrity, and morphological preservation compared with AgNPs at equal Ag concentration. Copyright © 2017 Elsevier Ltd. All rights reserved.
Astronomers Travel in Time and Space with Light
NASA Technical Reports Server (NTRS)
Mather, John C.
2016-01-01
This is an excerpt of John Mather's in a book titled: INSPIRED BY LIGHT, Reflections from the International Year of Light 2015. It was produced in January 2016 by SPIE, the European Physical Society (EPS), and The Abdus Salam International Centre for Theoretical Physics (ICTP) to commemorate the International Year of Light and Light-based Technologies 2015. The excerpt discusses how astronomers use light.
ERIC Educational Resources Information Center
Bischoff, Paul J.; Castendyk, Devin; Gallagher, Hugh; Schaumloffel, John; Labroo, Sunil
2008-01-01
Now in its fifth year, PR[superscript 2]EPS is a National Science Foundation funded initiative designed to recruit high school students to attend college majoring in the physical sciences, including engineering and secondary science education, and to help ensure their retention within these programs until graduation. A central feature of the…
New insights into environmental enteric dysfunction
USDA-ARS?s Scientific Manuscript database
Environmental enteric dysfunction (EED) has been recognised as an important contributing factor to physical and cognitive stunting, poor response to oral vaccines, limited resilience to acute infections and ultimately global childhood mortality. The aetiology of EED remains poorly defined but the ep...
How Bright is the Proton? A Precise Determination of the Photon Parton Distribution Function
DOE Office of Scientific and Technical Information (OSTI.GOV)
Manohar, Aneesh; Nason, Paolo; Salam, Gavin P.
2016-12-09
It has become apparent in recent years that it is important, notably for a range of physics studies at the Large Hadron Collider, to have accurate knowledge on the distribution of photons in the proton. We show how the photon parton distribution function (PDF) can be determined in a model-independent manner, using electron-proton (ep) scattering data, in effect viewing the ep → e + X process as an electron scattering off the photon field of the proton. To this end, we consider an imaginary, beyond the Standard Model process with a flavor changing photon-lepton vertex. We write its cross sectionmore » in two ways: one in terms of proton structure functions, the other in terms of a photon distribution. Requiring their equivalence yields the photon distribution as an integral over proton structure functions. As a result of the good precision of ep data, we constrain the photon PDF at the level of 1%–2% over a wide range of momentum fractions.« less
Magnetic Resonance Based Electrical Properties Tomography: A Review
Zhang, Xiaotong; Liu, Jiaen
2014-01-01
Frequency-dependent electrical properties (EPs; conductivity and permittivity) of biological tissues provide important diagnostic information (e.g. tumor characterization), and also play an important role in quantifying radiofrequency (RF) coil induced Specific Absorption Rate (SAR) which is a major safety concern in high- and ultrahigh-field Magnetic Resonance Imaging (MRI) applications. Cross-sectional imaging of EPs has been pursued for decades. Recently introduced Electrical Properties Tomography (EPT) approaches utilize the measurable RF magnetic field induced by the RF coil in an MRI system to quantitatively reconstruct the EP distribution in vivo and non-invasively with a spatial resolution of a few millimeters or less. This paper reviews the Electrical Properties Tomography approach from its basic theory in electromagnetism to the state of the art research outcomes. Emphasizing on the imaging reconstruction methods rather than experimentation techniques, we review the developed imaging algorithms, validation results in physical phantoms and biological tissues, as well as their applications in in vivo tumor detection and subject-specific SAR prediction. Challenges for future research are also discussed. PMID:24803104
The Microscope Space Mission and the In-Orbit Calibration Plan for its Instrument
NASA Astrophysics Data System (ADS)
Levy, Agnès Touboul, Pierre; Rodrigues, Manuel; Onera, Émilie Hardy; Métris, Gilles; Robert, Alain
2015-01-01
The MICROSCOPE space mission aims at testing the Equivalence Principle (EP) with an accuracy of 10-15. This principle is one of the basis of the General Relativity theory; it states the equivalence between gravitational and inertial mass. The test is based on the precise measurement of a gravitational signal by a differential electrostatic accelerometer which includes two cylindrical test masses made of different materials. The accelerometers constitute the payload accommodated on board a drag-free micro-satellite which is controlled inertial or rotating about the normal to the orbital plane. The acceleration estimates used for the EP test are disturbed by the instruments physical parameters and by the instrument environment conditions on-board the satellite. These parameters are partially measured with ground tests or during the integration of the instrument in the satellite (alignment). Nevertheless, the ground evaluations are not sufficient with respect to the EP test accuracy objectives. An in-orbit calibration is therefore needed to characterize them finely. The calibration process for each parameter has been defined.
Investigating the laser heating of underdense plasmas at conditions relevant to MagLIF
NASA Astrophysics Data System (ADS)
Harvey-Thompson, Adam
2015-11-01
The magnetized Liner Inertial Fusion (MagLIF) scheme has achieved thermonuclear fusion yields on Sandia's Z Facility by imploding a cylindrical liner filled with D2 fuel that is preheated with a multi-kJ laser and pre-magnetized with an axial field Bz = 10 T. The challenge of fuel preheating in MagLIF is to deposit several kJ's of energy into an underdense (ne/ncrit<0.1) fusion fuel over ~ 10 mm target length efficiently and without introducing contaminants that could contribute to unacceptable radiative losses during the implosion. Very little experimental work has previously been done to investigate laser heating of gas at densities, scale lengths, modest intensities (Iλ2 ~ 1014 watts- μm2 /cm2) and magnetization parameters (ωceτe ~ 10) necessary for MagLIF. In particular, magnetization of the preheated plasma suppresses electron thermal conduction, which can modify laser energy coupling. Providing an experimental dataset in this regime is essential to not only understand the dynamics of a MagLIF implosion and stagnation, but also to validate magnetized transport models and better understand the physics of laser propagation in magnetized plasmas. In this talk, we present data and analysis of several experiments conducted at OMEGA-EP and at Z to investigate laser propagation and plasma heating in underdense D2 plasmas under a range of conditions, including densities (ne = 0.05-0.1 nc) and magnetization parmaters (ωceτe ~ 0-10). The results show differences in the electron temperature of the heated plasma and the velocity of the laser burn wave with and without an applied magnetic field. We will show comparisons of these experimental results to 2D and 3D HYDRA simulations, which show that the effect of the magnetic field on the electron thermal conduction needs to be taken into account when modeling laser preheat. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the National Nuclear Security Administration under Contract No. DE-AC04-94AL85000.
Multiprobe characterization of plasma flows for space propulsion
NASA Astrophysics Data System (ADS)
Damba, Julius; Argente, P.; Maldonado, P. E.; Cervone, A.; Domenech-Garret, J. L.; Conde, L.
2018-02-01
Plasma engines for space propulsion generate plasma jets (also denominated plasma plumes) having supersonic ion groups with typical speeds in the order of tens of kilometers per second, which lies between electron and ion thermal speeds. Studies of the stationary plasma expansion process using a four-grid retarding field energy analyzer (RFEA), an emissive probe (EP) and a Langmuir probe (LP), all mounted on a three dimensionally (3D) displaced multiprobe structure are discussed. Specifically, the determination of plasma beam properties from the RFEA current-voltage (IV) characteristic curves is presented. The experimental results show the ion energy spectra to be essentially unchanged over 300 mm along the plasma-jet expansion axis of symmetry. The measured ion velocity distribution function (IVDF) results from the superposition of different ion groups and has two dominant populations: A low-energy group constituted of ions from the background plasma is produced by the interaction of the plasma jet with the walls of the vacuum chamber. The fast-ion population is composed of ions from the plasma beam moving at supersonic speeds with respect to the low-energy ions. The decreasing spatial profiles of the plasma-jet current density are compared with those of the low-energy ion group, which are not uniform along the axis of symmetry because of the small contributions from other ion populations with intermediate speeds.
Validating predictive models for fast ion profile relaxation in burning plasmas
Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; ...
2016-07-22
The redistribution and potential loss of energetic particles due to MHD modes can limit the performance of fusion plasmas by reducing the plasma heating rate. In this work, we present validation studies of the 1.5D critical gradient model (CGM) for Alfvén eigenmode (AE) induced EP transport in NSTX and DIII-D neutral beam heated plasmas. In previous comparisons with a single DIII-D L-mode case, the CGM model was found to be responsible for 75% of measured AE induced neutron deficit [1]. A fully kinetic HINST is used to compute mode stability for the non-perturbative version of CGM (or nCGM). We have found that AEs show strong local instability drive up tomore » $$\\gamma /\\omega \\sim 20\\%$$ violating assumptions of perturbative approaches used in NOVA-K code. Lastly, we demonstrate that both models agree with each other and both underestimate the neutron deficit measured in DIII-D shot by approximately a factor of 2.« less
Huang, Hann-Sheng; Gorski, Anthony J.
1999-01-01
An apparatus and process that utilize a low temperature nonequilibrium plasma reactor, for improving the particulate removal efficiency of an electrostatic precipitator (ESP) are disclosed. A portion of the flue gas, that contains a low level of SO.sub.2 O.sub.2 H.sub.2 O, and particulate matter, is passed through a low temperature plasma reactor, which defines a plasma volume, thereby oxidizing a portion of the SO.sub.2 present in the flue gas into SO.sub.3. An SO.sub.2 rich flue gas is thereby generated. The SO.sub.3 rich flue gas is then returned to the primary flow of the flue gas in the exhaust treatment system prior to the ESP. This allows the SO.sub.3 to react with water to form H.sub.2 SO.sub.4 that is in turn is absorbed by fly ash in the gas stream in order to improve the removal efficiency of the EPS.
Outgassing Total Mass Loss Obtained with Micro-CVCM and Other Vacuum Systems
NASA Technical Reports Server (NTRS)
Scialdone, John; Isaac, Peggy; Clatterbuck, Carroll; Hunkeler, Ronald; Powers, Edward I. (Technical Monitor)
2000-01-01
Several instruments including the Cahn Microbalance, the Knudsen Cell, the micro-CVCM, and the vacuum Thermogravimetric Analyzer (TGA) were used in the testing of a graphite epoxy (GR/EP) composite that is proposed for use as a rigidizing element of an inflatable deployment system. This GR/EP will be cured in situ. The purpose of this testing is to estimate the gaseous production resulting from the curing of the GR/EP composite, to predict the resulting pressure, and to calculate the required venting. Every test was conducted under vacuum at 125 C for 24 hours. Upon comparison of the results, the ASTM E-595 was noted to have given readings that were consistently lower than those obtained using the other instruments, which otherwise provided similar results. The GR/EP was tested using several different geometric arrangements. This paper describes the analysis evaluating the molecular and continuum flow of the outgassing products issuing from the exit port of the ASTM E-595 system. The effective flow conductance provided by the physical dimensions of the vent passage of the ASTM E-595 system and that of the material sample among other factors were investigated to explain the reduced amount of outgassing released during the 24-hour test period,
Material Total Mass Loss in Vacuum Obtained From Various Outgassing Systems
NASA Technical Reports Server (NTRS)
Scialdone, John; Isaac, Peggy; Clatterbuck, Carroll; Hunkeler, Ronald
2000-01-01
Several instruments including the Cahn Microbalance, the Knudsen Cell, the micro-CVCM, and the vacuum Thermogravimetric Analyzer (TGA) were used in the testing of a graphite/epoxy (GR/EP) composite that is proposed for use as a rigidizing element of an inflatable deployment system. This GR/EP will be cured in situ. The purpose of this testing is to estimate the gaseous production resulting from the curing of the GR/EP composite, to predict the resulting pressure, and to calculate the required venting. Every test was conducted under vacuum at 125 degrees C for 24 hours. Upon comparison of the results, the ASTM E-595 was noted to have given readings that were consistently lower than those obtained using the other instruments, which otherwise provided similar results. The GR/EP was tested using several different geometric arrangements. This paper describes the analysis evaluating the molecular and continuum flow of the outgassing products issuing from the exit port of the ASTM E-595 system. The effective flow conductance provided by the physical dimensions of the vent passage of the ASTM E-595 system and that of the material sample among other factors were investigated to explain the reduced amount of outgassing released during the 24-hour test period.
Outgassing Total Mass Loss Obtained with Micro-CVCM and other Vacuum Systems
NASA Technical Reports Server (NTRS)
Scialdone, John J.; Isaac, Peggy A.; Clatterbuck, Carroll H.; Hunkeler, Ronald E.; Powers, Edward I. (Technical Monitor)
2000-01-01
Several instruments including the Cahn Microbalance the Knudsen Cell, the micro-CVCM, and the vacuum Thermogravimetric Analyzer (TGA) were used in the testing of a graphite epoxy (GR/EP) composite that is proposed for use as a rigidizing element of an inflatable deployment system. This GR/EP will be cured in situ. The purpose of this testing is to estimate the gaseous production resulting from the curing of the GR/EP composite, to predict the resulting pressure, and to calculate the required venting. Every test was conducted under vacuum at 125 C for 24 hours. Upon comparison of the results, the ASTM E-595 was noted to have given readings that were consistently lower than those obtained using the other instruments, which otherwise provided similar results. The GR/EP was tested using several different geometric arrangements. This paper describes the analysis evaluating the molecular and continuum flow of the outgassing products issuing from the exit port of the ASTM E-595 system. The effective flow conductance provided by the physical dimensions of the vent passage of the ASTM E-595 system and that of the material sample among other factors were investigated to explain the reduced amount of outgassing released during the 24-hour test period
Chikkanna, Arpitha; Kishore, Abhinoy
2018-01-01
The halophilic bacterial strain WB1 isolated from a hydrothermal vent was taxonomically characterized using multiple proxies, as Halomonas nitroreducens strain WB1. When grown on malt extract/yeast extract (MY) medium, it produced large quantities of exopolysaccharide (EPS). The polymer was synthesized at a higher rate during the log and early stationary phases. The anionic polysaccharide is primarily composed of glucose, mannose, and galactose. The studied EPS was highly viscous and had pseudoplastic nature. The EPS was found to be a mixture of three polysaccharides under FT-IR, which makes it less labile to environmental diagenesis. It also has emulsifying and antioxidant activity along with the binding capacity to heavy metals. The EPS has unique and interesting physical and chemical properties, which are different from earlier reported exo-polysaccharides produced by different bacterial genus. This suggests that the extreme geological niches like hypersaline, hyperthermal, hypothermal, and oligophilic environments, which are not well studied so far, can offer extensive and potential resources for medical, biotechnological and industrial applications. The study clearly showed that the thermal springs from the temperate region can be a potent source of many such industrially important microbial genera and need further detailed studies to be carried out. PMID:29707437
Sensitivity Studies in Gyro-fluid Simulation
NASA Astrophysics Data System (ADS)
Ross, D. W.; Dorland, W.; Beer, M. A.; Hammett, G. W.
1998-11-01
Transport models [1] derived from gyrofluid simulation [2] have been successful in predicting general confinement scalings. Specific fluxes and turbulent spectra, however, can depend sensitively on the plasma configuration and profiles, particularly in experiments with transients. Here, we step back from initial studies on Alcator C-Mod [3] and DIII-D [4] to investigate the sensitivity of simulations to variations in density, temperature (and their gradients) of each plasma species. We discuss the role of electric field shear, and the construction of local transport models for experimental comparison. In accompanying papers [5] we investigate comparisons with the experiments. *Supported by USDOE Grants DE-FG03-95ER54296, and DE-AC02-76CHO3073. [1] M. Kotschenreuther et al., Phys. Plasmas 2, 2381 (1995). [2] M. A. Beer et al, Phys. Plasmas 2, 2687 (1995). [3] D. W. Ross et al., Transport Task Force, Atlanta, 1998. [4] R. V. Bravenec et al., in Proc. 25th EPS Conf. on Contr. Fusion and Plasma Phys., Prague (1998). [5] R. V. Bravenec et al. and W. L. Rowan et al., these proceedings.
High-power, kilojoule laser interactions with near-critical density plasma
DOE Office of Scientific and Technical Information (OSTI.GOV)
Willingale, L.; Thomas, A. G. R.; Maksimchuk, A.
Experiments were performed using the Omega EP laser, which provided pulses containing 1kJ of energy in 9ps and was used to investigate high-power, relativistic intensity laser interactions with near-critical density plasmas, created from foam targets with densities of 3-100 mg/cm{sup 3}. The effect of changing the plasma density on both the laser light transmitted through the targets and the proton beam accelerated from the interaction was investigated. Two-dimensional particle-in-cell simulations enabled the interaction dynamics and laser propagation to be studied in detail. The effect of the laser polarization and intensity in the two-dimensional simulations on the channel formation and electronmore » heating are discussed. In this regime, where the plasma density is above the critical density, but below the relativistic critical density, the channel formation speed and therefore length are inversely proportional to the plasma density, which is faster than the hole boring model prediction. A general model is developed to describe the channel length in this regime.« less
Emission of energetic protons from relativistic intensity laser interaction with a cone-wire target.
Paradkar, B S; Yabuuchi, T; Sawada, H; Higginson, D P; Link, A; Wei, M S; Stephens, R B; Krasheninnikov, S I; Beg, F N
2012-11-01
Emission of energetic protons (maximum energy ∼18 MeV) from the interaction of relativistic intensity laser with a cone-wire target is experimentally measured and numerically simulated with hybrid particle-in-cell code, lsp [D. R. Welch et al., Phys. Plasmas 13, 063105 (2006)]. The protons originate from the wire attached to the cone after the OMEGA EP laser (670 J, 10 ps, 5 × 10^{18} W/cm^{2}) deposits its energy inside the cone. These protons are accelerated from the contaminant layer on the wire surface, and are measured in the radial direction, i.e., in a direction transverse to the wire length. Simulations show that the radial electric field, responsible for the proton acceleration, is excited by three factors, viz., (i) transverse momentum of the relativistic fast electrons beam entering into the wire, (ii) scattering of electrons inside the wire, and (iii) refluxing of escaped electrons by "fountain effect" at the end of the wire. The underlying physics of radial electric field and acceleration of protons is discussed.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt... Waste, Physical/Chemical Methods,” EPA Publication SW-846, as incorporated by reference in § 260.11 of...
Code of Federal Regulations, 2011 CFR
2011-07-01
... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt... Waste, Physical/Chemical Methods,” EPA Publication SW-846, as incorporated by reference in § 260.11 of...
Code of Federal Regulations, 2014 CFR
2014-07-01
... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt... Waste, Physical/Chemical Methods,” EPA Publication SW-846, as incorporated by reference in § 260.11 of...
Code of Federal Regulations, 2012 CFR
2012-07-01
... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt... Waste, Physical/Chemical Methods,” EPA Publication SW-846, as incorporated by reference in § 260.11 of...
Code of Federal Regulations, 2010 CFR
2010-07-01
... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS Pt... Waste, Physical/Chemical Methods,” EPA Publication SW-846, as incorporated by reference in § 260.11 of...
Diagnosing laser-preheated magnetized plasmas relevant to magnetized liner inertial fusion
Harvey-Thompson, Adam James; Sefkow, Adam B.; Nagayama, Taisuke N.; ...
2015-12-22
In this paper, we present a platform on the OMEGA EP Laser Facility that creates and diagnoses the conditions present during the preheat stage of the MAGnetized Liner Inertial Fusion (MagLIF) concept. Experiments were conducted using 9 kJ of 3ω (355 nm) light to heat an underdense deuterium gas (electron density: 2.5 × 10 20 cm -3 = 0.025 of critical density) magnetized with a 10 T axial field. Results show that the deuterium plasma reached a peak electron temperature of 670 ± 140 eV, diagnosed using streaked spectroscopy of an argon dopant. The results demonstrate that plasmas relevant tomore » the preheat stage of MagLIF can be produced at multiple laser facilities, thereby enabling more rapid progress in understanding magnetized preheat. Results are compared with magneto-radiation-hydrodynamics simulations, and plans for future experiments are described.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.
The redistribution and potential loss of energetic particles due to MHD modes can limit the performance of fusion plasmas by reducing the plasma heating rate. In this work, we present validation studies of the 1.5D critical gradient model (CGM) for Alfvén eigenmode (AE) induced EP transport in NSTX and DIII-D neutral beam heated plasmas. In previous comparisons with a single DIII-D L-mode case, the CGM model was found to be responsible for 75% of measured AE induced neutron deficit [1]. A fully kinetic HINST is used to compute mode stability for the non-perturbative version of CGM (or nCGM). We have found that AEs show strong local instability drive up tomore » $$\\gamma /\\omega \\sim 20\\%$$ violating assumptions of perturbative approaches used in NOVA-K code. Lastly, we demonstrate that both models agree with each other and both underestimate the neutron deficit measured in DIII-D shot by approximately a factor of 2.« less
IEEE Conference Record of 1980 Fourteenth Pulse Power Modulator Symposium, 3-5 June 1980.
1980-01-01
attachment and generation coefficients, usually given volume can control the velocity of the streamer phase as a function of E/P. Data on experimentally ...more foils could be used if desired. The mechanical design for the electron beau Experimental Program controlled switch has two competing requirenmts...deter- mine the effect of the plasma conditioning as compared to the control tests. 2W C C TABLE I: SUMMARY OF EXPERIMENTAL PROCEDURE • ur EIIEIT
PR2EPS: Preparation, Recruitment, Retention and Excellence in the Physical Sciences
NASA Astrophysics Data System (ADS)
Gallagher, H. A.; Schaumloffel, J. C.; Bischoff, P.; Labroo, S.; Bachman, N.
2006-05-01
PR2EPS is a multifaceted NSF-DUE sponsored program at SUNY Oneonta that strives to enhance the number of students pursuing degrees in the physical sciences and increase the retention rate of students pursuing STEM degrees. A key focus of the project, which is beginning its third year, is drawing students from the five rural counties surrounding Oneonta, NY. Team members visit 15 to 20 local high schools each year leading discussions on academic and career opportunities in STEM disciplines and inviting students to participate in a one week summer science camp. A variety of hands-on science and engineering activities are designed to engage students and demonstrate to them that they possess the requisite skills and potential to succeed in these technically demanding disciplines. Campers who decide to study physical science at SUNY Oneonta are supported with a modest financial inducement and an evening tutoring center. As these students progress, they gain exposure to research and professional activities designed to show them opportunities and developments in their field and integrate them into the broader community of learners. A description of the program, which is a collaboration of faculty from the Departments of Physics & Astronomy, Chemistry & Biochemistry and Education, as well as an evaluation of the effectiveness of the overall program and its components will be provided.
HBT-EP Program: MHD Dynamics and Active Control through 3D Fields and Currents
NASA Astrophysics Data System (ADS)
Navratil, G. A.; Bialek, J.; Brooks, J. W.; Byrne, P. J.; Desanto, S.; Levesque, J. P.; Mauel, M. E.; Stewart, I. G.; Hansen, C. J.
2017-10-01
The HBT-EP active mode control research program aims to: (i) advance understanding of the effects of 3D shaping on advanced tokamak fusion performance, (ii) resolve important MHD issues associated with disruptions, and (iii) measure and mitigate the effects of 3D scrape-off layer (SOL) currents through active and passive control of the plasma edge and conducting boundary structures. Comparison of kink mode structure and RMP response in circular versus diverted plasmas shows good agreement with DCON modeling. SOL current measurements have been used to study SOL current dynamics and current-sharing with the vacuum vessel wall during kink-mode growth and disruptions. A multi-chord extreme UV/soft X-ray array is being installed to provide detailed internal mode structure information. Internal local electrodes were used to apply local bias voltage at two radial locations to study the effect of rotation profile on MHD mode rotation and stability and radial current flow through the SOL. A GPU-based low latency control system using 96 inputs and 64 outputs to apply magnetic perturbations for active control of kink modes is extended to directly control the SOL currents for kink-mode control. An extensive array of SOL current monitors and edge drive electrodes are being installed for pioneering studies of helical edge current control. Supported by U.S. DOE Grant DE-FG02-86ER53222.
Osaku, Erica F; Menolli, Rafael A; de M Costa, Claudia R L; Tessaro, Fernando Henrique G; de Melo, Renan H; do Amaral, Alex E; Duarte, Péricles A D; de Santana Filho, Arquimedes Paixão; Ruthes, Andrea Caroline; da C Silva, José Luis; Mello, Rosiane G
2018-06-01
Paecilomyces variotii is a filamentous fungus that occurs worldwide in soil and decaying vegetation. Optimization of the fermentation process for exopolysaccharide (EPS) production from the fungus P. variotii, structure determination and immuno-stimulating activity of EPS were performed. Response surface methodology (RSM) coupled with central composite design (CCD) was used to optimize the physical and chemical factors required to produce EPS in submerged fermentation. Preliminary investigations to choose the three factors for the present work were made using a factorial experimental design. Glucose, ammonium nitrate (NH 4 NO 3 ) and pH were used as variables for which, with constant temperature of 28 °C and agitation of 90 rpm, the optimal process parameters were determined as glucose values of 0.96%, NH 4 NO 3 0.26% and pH 8.0. The three parameters presented significant effects. In this condition of culture, the main composition of the isolated EPS was a linear β-(1 → 6)-linked-D-glucan, as determined by Nuclear Magnetic Resonance (NMR) and methylation analysis. This polysaccharide is a very unusual as an EPS from fungi, especially a filamentous fungus such as P. variotii. Murine peritoneal macrophages cultivated with β-glucan for 6 and 48 h showed an increase in TNF-α, IL-6 and nitric oxide release with increased polysaccharide concentrations. Therefore, we conclude that the β-(1 → 6)-linked-D-glucan produced in optimised conditions of P. variotii cultivation has an immune-stimulatory activity on murine macrophages.
de Brito, Audrey Kalinouski; Nordi, Cristina S F; Caseli, Luciano
2015-11-01
Currently, many biological substances extracted from algae have received special attention because of their intrinsic characteristics, which can be applied to different areas of biotechnology. Therefore, in the current study, exopolysaccharides (EPS) from the microalgae Cryptomonas tetrapirenoidosa were employed as an aqueous subphase of a monolayer formed by the lipid dioctadecyldimethylammonium bromide (DODAB). The primary objective of this approach was to evaluate whether EPS could serve as a matrix for the immobilization of the enzyme urease to produce biosensors for urea. After DODAB was spread on the EPS solutions, urease was injected into the aqueous subphase, and the surface was submitted to compression using lateral barriers. The monolayers were subsequently characterized by surface pressure-area isotherms and polarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS). The results indicated that EPS enhanced the adsorption of the enzyme on the lipid monolayer. The mixed films were later transferred to solid supports using the Langmuir-Blodgett (LB) technique and were characterized by transfer ratio, PM-IRRAS, quartz crystal microbalance, and atomic force microscopy. The immobilization of the enzyme on solid supports was fundamental for providing an ideal geometrical accommodation of urease because the interaction of EPS with urease in solution causes a decrease of the relative activity of urease. Therefore, these LB films are promising for the fabrication of future urea biosensors, the architecture of which can be manipulated and enhanced at the molecular level. Copyright © 2015 Elsevier B.V. All rights reserved.
Kene, Mamata V; Ballard, Dustin W; Vinson, David R; Rauchwerger, Adina S; Iskin, Hilary R; Kim, Anthony S
2015-09-01
We evaluated emergency physicians' (EP) current perceptions, practice, and attitudes towards evaluating stroke as a cause of dizziness among emergency department patients. We administered a survey to all EPs in a large integrated healthcare delivery system. The survey included clinical vignettes, perceived utility of historical and exam elements, attitudes about the value of and requisite post-test probability of a clinical prediction rule for dizziness. We calculated descriptive statistics and post-test probabilities for such a clinical prediction rule. The response rate was 68% (366/535). Respondents' median practice tenure was eight years (37% female, 92% emergency medicine board certified). Symptom quality and typical vascular risk factors increased suspicion for stroke as a cause of dizziness. Most respondents reported obtaining head computed tomography (CT) (74%). Nearly all respondents used and felt confident using cranial nerve and limb strength testing. A substantial minority of EPs used the Epley maneuver (49%) and HINTS (head-thrust test, gaze-evoked nystagmus, and skew deviation) testing (30%); however, few EPs reported confidence in these tests' bedside application (35% and 16%, respectively). Respondents favorably viewed applying a properly validated clinical prediction rule for assessment of immediate and 30-day stroke risk, but indicated it would have to reduce stroke risk to <0.5% to be clinically useful. EPs report relying on symptom quality, vascular risk factors, simple physical exam elements, and head CT to diagnose stroke as the cause of dizziness, but would find a validated clinical prediction rule for dizziness helpful. A clinical prediction rule would have to achieve a 0.5% post-test stroke probability for acceptability.
Anomalous heating and plasmoid formation in pulsed power driven magnetic reconnection experiments
NASA Astrophysics Data System (ADS)
Hare, Jack
2017-10-01
Magnetic reconnection is an important process occurring in various plasma environments, including high energy density plasmas. In this talk we will present results from a recently developed magnetic reconnection platform driven by the MAGPIE pulsed power generator (1 MA, 250 ns) at Imperial College London. In these experiments, supersonic, sub-Alfvénic plasma flows collide, bringing anti-parallel magnetic fields into contact and producing a well-defined, elongated reconnection layer. This layer is long-lasting (>200 ns, > 10 hydrodynamic flow times) and is diagnosed using a suite of high resolution, spatially and temporally resolved diagnostics which include laser interferometry, Thomson scattering and Faraday rotation imaging. We observe significant heating of the electrons and ions inside the reconnection layer, and calculate that the heating must occur on time-scales far faster than can be explained by classical mechanisms. Possible anomalous mechanisms include in-plane electric fields caused by two-fluid effects, and enhanced resistivity and viscosity caused by kinetic turbulence. We also observe the repeated formation of plasmoids in the reconnection layer, which are ejected outwards along the layer at super-Alfvénic velocities. The O-point magnetic field structure of these plasmoids is determined using in situ magnetic probes, and these plasmoids could also play a role in the anomalous heating of the electrons and ions. In addition, we present further modifications to this experimental platform which enable us to study asymmetric reconnection or measure the out-of-plane magnetic field inside the plasmoids. This work was supported in part by the Engineering and Physical Sciences Research Council (EPSRC) Grant No. EP/N013379/1, and by the U.S. Department of Energy (DOE) Awards No. DE-F03-02NA00057 and No. DE-SC-0001063.
Improved Design of Stellarator Coils for Current Carrying Plasmas
NASA Astrophysics Data System (ADS)
Drevlak, M.; Strumberger, E.; Hirshman, S.; Boozer, A.; Brooks, A.; Valanju, P.
1998-11-01
The method of automatic optimization (P. Merkel, Nucl. Fus. 27), (1987) 867; P. Merkel, M. Drevlak, Proc 25th EPS Conf. on Cont. Fus. and Plas. Phys., Prague, in print. for the design of stellarator coils consists essentially of determining filaments such that the average relative field error int dS [ (B_coil + B_j) \\cdot n]^2/B^2_coil is minimized on the prescribed plasma boundary. Bj is the magnetic field produced by the plasma currents of the given finite β fixed boundary equilibrium. For equilibria of the W7-X type, Bj can be neglected, because of the reduced parallel plasma currents. This is not true for quasi-axisymmetric stellarator (QAS) configurations (A. Reiman, et al., to be published.) with large equilibrium and net plasma (bootstrap) currents. Although the coils for QAS exhibit low values of the field error, free boundary calculations indicate that the shape of the plasma is usually not accurately reproduced , particularly when saddle coils are used. We investigate if the surface reconstruction can be improved by introducing a modified measure of the field error based on a measure of the resonant components of the normal field.
Epididymosomes: transfer of fertility-modulating proteins to the sperm surface
Martin-DeLeon, Patricia A
2015-01-01
A variety of glycosylphosphatidylinositol (GPI)-linked proteins are acquired on spermatozoa from epididymal luminal fluids (ELF) during sperm maturation. These proteins serve roles in immunoprotection and in key steps of fertilization such as capacitation, acrosomal exocytosis and sperm-egg interactions. Their acquisition on sperm cells is mediated both by membrane vesicles (epididymosomes, EP) which were first reported to dock on the sperm surface, and by lipid carriers which facilitate the transfer of proteins associated with the membrane-free fraction of ELF. While the nonvesicular fraction is more efficient, both pathways are dependent on hydrophobic interactions between the GPI-anchor and the external lipid layer of the sperm surface. More recently proteomic and hypothesis-driven studies have shown that EP from several mammals carry transmembrane (TM) proteins, including plasma membrane Ca2+-ATPase 4 (PMCA4). Synthesized in the testis, PMCA4 is an essential protein and the major Ca2+ efflux pump in murine spermatozoa. Delivery of PMCA4 to spermatozoa from bovine and mouse EP during epididymal maturation and in vitro suggests that the docking of EP on the sperm surface precedes fusion, and experimental evidence supports a fusogenic mechanism for TM proteins. Fusion is facilitated by CD9, which generates fusion–competent sites on membranes. On the basis of knowledge of PMCA4's interacting partners a number of TM and membrane-associated proteins have been identified or are predicted to be present, in the epididymosomal cargo deliverable to spermatozoa. These Ca2+-dependent proteins, undetected in proteomic studies, play essential roles in sperm motility and fertility, and their detection highlights the usefulness of the hypothesis-driven approach. PMID:26112481
Epididymosomes: transfer of fertility-modulating proteins to the sperm surface.
Martin-DeLeon, Patricia A
2015-01-01
A variety of glycosylphosphatidylinositol (GPI)-linked proteins are acquired on spermatozoa from epididymal luminal fluids (ELF) during sperm maturation. These proteins serve roles in immunoprotection and in key steps of fertilization such as capacitation, acrosomal exocytosis and sperm-egg interactions. Their acquisition on sperm cells is mediated both by membrane vesicles (epididymosomes, EP) which were first reported to dock on the sperm surface, and by lipid carriers which facilitate the transfer of proteins associated with the membrane-free fraction of ELF. While the nonvesicular fraction is more efficient, both pathways are dependent on hydrophobic interactions between the GPI-anchor and the external lipid layer of the sperm surface. More recently proteomic and hypothesis-driven studies have shown that EP from several mammals carry transmembrane (TM) proteins, including plasma membrane Ca 2 + -ATPase 4 (PMCA4). Synthesized in the testis, PMCA4 is an essential protein and the major Ca 2 + efflux pump in murine spermatozoa. Delivery of PMCA4 to spermatozoa from bovine and mouse EP during epididymal maturation and in vitro suggests that the docking of EP on the sperm surface precedes fusion, and experimental evidence supports a fusogenic mechanism for TM proteins. Fusion is facilitated by CD9, which generates fusion-competent sites on membranes. On the basis of knowledge of PMCA4's interacting partners a number of TM and membrane-associated proteins have been identified or are predicted to be present, in the epididymosomal cargo deliverable to spermatozoa. These Ca 2 + -dependent proteins, undetected in proteomic studies, play essential roles in sperm motility and fertility, and their detection highlights the usefulness of the hypothesis-driven approach.
Evoked potentials in multiple sclerosis.
Kraft, George H
2013-11-01
Before the development of magnetic resonance imaging (MRI), evoked potentials (EPs)-visual evoked potentials, somatosensory evoked potentials, and brain stem auditory evoked responses-were commonly used to determine a second site of disease in patients being evaluated for possible multiple sclerosis (MS). The identification of an area of the central nervous system showing abnormal conduction was used to supplement the abnormal signs identified on the physical examination-thus identifying the "multiple" in MS. This article is a brief overview of additional ways in which central nervous system (CNS) physiology-as measured by EPs-can still contribute value in the management of MS in the era of MRIs. Copyright © 2013 Elsevier Inc. All rights reserved.
Calabrese, Sarah K; Dovidio, John F; Tekeste, Mehrit; Taggart, Tamara; Galvao, Rachel W; Safon, Cara B; Willie, Tiara C; Caldwell, Abigail; Kaplan, Clair; Kershaw, Trace S
2018-05-22
PrEP uptake has lagged among US women. PrEP stigma is a recognized barrier to uptake among MSM but remains largely unexplored among women. This study examined the pervasiveness of PrEP stigma among US women and its implications for uptake. Setting/Methods: In a 2017 online survey of Planned Parenthood patients drawn from the three cities with the highest numbers of new HIV infections in Connecticut, 597 heterosexually-active, HIV-negative, PrEP-inexperienced women reported background characteristics, two dimensions of anticipated PrEP stigma (PrEP-user stereotypes and PrEP disapproval by others), and three indicators of potential PrEP uptake (interest in learning more about PrEP, intention to use PrEP, and comfort discussing PrEP with a provider). Participants commonly perceived PrEP-user stereotypes, with many believing that others would regard them as promiscuous (37%), HIV-positive (32%), bad (14%), or gay (11%) if they used PrEP. Thirty percent would feel ashamed to disclose PrEP use. Many participants expected disapproval by family (36%), sex partners (34%), and friends (25%). In adjusted analyses, perception of PrEP-user stereotypes was uniquely associated with lower comfort discussing PrEP with a provider. Expected PrEP disapproval by others was uniquely associated with less PrEP interest, less intention to use PrEP, and less comfort discussing PrEP with a provider. Exploratory moderation analyses suggested intention to use PrEP was greatest when participants anticipated low levels of both PrEP-user stereotypes and PrEP disapproval by others. Findings highlight the need for positive messaging targeting potential PrEP users and their social networks to increase PrEP acceptance and uptake.
Mikes, J; Siglova, M; Cejkova, A; Masak, J; Jirku, V
2005-01-01
Wastewaters from a chemical industry polluted by heavy metal ions represent a hazard for all living organisms. It can mean danger for ecosystems and human health. New methods are sought alternative to traditional chemical and physical processes. Active elimination process of heavy metals ions provided by living cells, their components and extracellular products represents a potential way of separating toxic heavy metals from industrial wastewaters. While the abilities of bacteria to remove metal ions in solution are extensively used, fungi have been recognized as a promising kind of low-cost adsorbents for removal of heavy-metal ions from aqueous waste sources. Yeasts and fungi differ from each other in their constitution and in their abilities to produce variety of extracellular polymeric substances (EPS) with different mechanisms of metal interactions. The accumulation of Cd(2+), Cr(6+), Pb(2+), Ni(2+) and Zn(2+) by yeasts and their EPS was screened at twelve different yeast species in microcultivation system Bioscreen C and in the shaking Erlenmayer's flasks. This results were compared with the production of yeast EPS and the composition of yeast cell walls. The EPS production was measured during the yeast growth and cell wall composition was studied during the cultivations in the shaking flasks. At the end of the process extracellular polymers and their chemical composition were isolated and amount of bound heavy metals was characterized. The variable composition and the amount of the EPS were found at various yeast strains. It was influenced by various compositions of growth medium and also by various concentrations of heavy metals. It is evident, that the amount of bound heavy metals was different. The work reviews the possibilities of usage of various yeast EPS and components of cell walls in the elimination processes of heavy metal ions. Further the structure and properties of yeasts cell wall and EPS were discussed. The finding of mechanisms mentioned above is necessary to identify the functional groups entered in the metals elimination processes.
30 CFR 250.216 - What biological, physical, and socioeconomic information must accompany the EP?
Code of Federal Regulations, 2011 CFR
2011-07-01
.... Site-specific information on chemosynthetic communities, federally listed threatened or endangered species, marine mammals protected under the Marine Mammal Protection Act (MMPA), sensitive underwater features, marine sanctuaries, critical habitat designated under the Endangered Species Act (ESA), or other...
Melas, P A; Lennartsson, A; Vakifahmetoglu-Norberg, H; Wei, Y; Åberg, E; Werme, M; Rogdaki, M; Mannervik, M; Wegener, G; Brené, S; Mathé, A A; Lavebratt, C
2013-05-07
Neuropeptide Y (NPY) has been implicated in depression, emotional processing and stress response. Part of this evidence originates from human single-nucleotide polymorphism (SNP) studies. In the present study, we report that a SNP in the rat Npy promoter (C/T; rs105431668) affects in vitro transcription and DNA-protein interactions. Genotyping studies showed that the C-allele of rs105431668 is present in a genetic rat model of depression (Flinders sensitive line; FSL), while the SNP's T-allele is present in its controls (Flinders resistant line; FRL). In vivo experiments revealed binding of a transcription factor (CREB2) and a histone acetyltransferase (Ep300) only at the SNP locus of the FRL. Accordingly, the FRL had increased hippocampal levels of Npy mRNA and H3K18 acetylation; a gene-activating histone modification maintained by Ep300. Next, based on previous studies showing antidepressant-like effects of physical activity in the FSL, we hypothesized that physical activity may affect Npy's epigenetic status. In line with this assumption, physical activity was associated with increased levels of Npy mRNA and H3K18 acetylation. Physical activity was also associated with reduced mRNA levels of a histone deacetylase (Hdac5). Conclusively, the rat rs105431668 appears to be a functional Npy SNP that may underlie depression-like characteristics. In addition, the achieved epigenetic reprogramming of Npy provides molecular support for the putative effectiveness of physical activity as a non-pharmacological antidepressant.
Melas, P A; Lennartsson, A; Vakifahmetoglu-Norberg, H; Wei, Y; Åberg, E; Werme, M; Rogdaki, M; Mannervik, M; Wegener, G; Brené, S; Mathé, A A; Lavebratt, C
2013-01-01
Neuropeptide Y (NPY) has been implicated in depression, emotional processing and stress response. Part of this evidence originates from human single-nucleotide polymorphism (SNP) studies. In the present study, we report that a SNP in the rat Npy promoter (C/T; rs105431668) affects in vitro transcription and DNA–protein interactions. Genotyping studies showed that the C-allele of rs105431668 is present in a genetic rat model of depression (Flinders sensitive line; FSL), while the SNP's T-allele is present in its controls (Flinders resistant line; FRL). In vivo experiments revealed binding of a transcription factor (CREB2) and a histone acetyltransferase (Ep300) only at the SNP locus of the FRL. Accordingly, the FRL had increased hippocampal levels of Npy mRNA and H3K18 acetylation; a gene-activating histone modification maintained by Ep300. Next, based on previous studies showing antidepressant-like effects of physical activity in the FSL, we hypothesized that physical activity may affect Npy's epigenetic status. In line with this assumption, physical activity was associated with increased levels of Npy mRNA and H3K18 acetylation. Physical activity was also associated with reduced mRNA levels of a histone deacetylase (Hdac5). Conclusively, the rat rs105431668 appears to be a functional Npy SNP that may underlie depression-like characteristics. In addition, the achieved epigenetic reprogramming of Npy provides molecular support for the putative effectiveness of physical activity as a non-pharmacological antidepressant. PMID:23652932
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-31
... NS Port Road Branch from Perrysburg, MD, Milepost (MP) PD-0.3, to Enola, PA, MP EP-68.2. The discontinuance would include automatic signals: PD 1.9, PD 6.4, PD 9.7, PD 15.7, PD 18.7, PD 23.6, PD 28.8, PD 35.7, EP 35.2, EP 40.0, EP 42.4, EP 47.6, EP 49.5, EP 53.6, EP 54.0, EP 58.3, EP 62.8, EP 67.1. The...
Electron temperature response to ECRH on FTU tokamak in transient conditions.
NASA Astrophysics Data System (ADS)
Jacchia, A.; Bruschi, A.; Cirant, S.; Granucci, G.; Sozzi, C.; de Luca, F.; Amadeo, P.; Bracco, G.; Tudisco, O.
2001-10-01
Steady-state electron heat transport analysis of FTU high density plasmas under Electron Cyclotron Heating (ECRH) shows "stiff" electron temperature profiles [1,2,3]. Plasma response to off-axis EC heating, in fact, exibits a lower limit to electron temperature gradient length, Lc , below which electron thermal conductivity switches to higher values. Stiffness, however, is attenuated in the plasma core of saw-tooth free discharges with flat-hollow temperature profile and during current ramp-up [3,4,5], in which cases the temperature gradient length can be brought to very low values by means of on-axis ECH. Steady and current ramp-up discharges probed by steady and modulated ECH are analyzed in terms of stiffnes. Critical gradient length dependence on local features of computed current density profile is discussed. [1] Sozzi, C. et al., Paper EXP5/13, Plasma Phys. Contr. Fus. Res., Proc.18th IAEA Conf., Sorrento, 2000. [2] Jacchia, A. et al. Topical Conference on Radio Frequency Power in Plasmas, Oxnard, USA, (2001). [3] Cirant, S. et al. Topical Conference on Radio Frequency Power in Plasmas, Oxnard, USA, (2001). [4] Sozzi, C. et al., EPS, Madeira 2001. [5] Bracco, G. et al.,Plasma Phys. Contr. Fus. Res., Proc.18th IAEA Conf., Sorrento, 2000.
30 CFR 250.216 - What biological, physical, and socioeconomic information must accompany the EP?
Code of Federal Regulations, 2010 CFR
2010-07-01
... information on chemosynthetic communities, federally listed threatened or endangered species, marine mammals protected under the Marine Mammal Protection Act (MMPA), sensitive underwater features, marine sanctuaries, critical habitat designated under the Endangered Species Act (ESA), or other areas of biological concern...
30 CFR 550.216 - What biological, physical, and socioeconomic information must accompany the EP?
Code of Federal Regulations, 2012 CFR
2012-07-01
... information on chemosynthetic communities, federally listed threatened or endangered species, marine mammals protected under the Marine Mammal Protection Act (MMPA), sensitive underwater features, marine sanctuaries, critical habitat designated under the Endangered Species Act (ESA), or other areas of biological concern...
30 CFR 550.216 - What biological, physical, and socioeconomic information must accompany the EP?
Code of Federal Regulations, 2014 CFR
2014-07-01
... information on chemosynthetic communities, federally listed threatened or endangered species, marine mammals protected under the Marine Mammal Protection Act (MMPA), sensitive underwater features, marine sanctuaries, critical habitat designated under the Endangered Species Act (ESA), or other areas of biological concern...
30 CFR 550.216 - What biological, physical, and socioeconomic information must accompany the EP?
Code of Federal Regulations, 2013 CFR
2013-07-01
... information on chemosynthetic communities, federally listed threatened or endangered species, marine mammals protected under the Marine Mammal Protection Act (MMPA), sensitive underwater features, marine sanctuaries, critical habitat designated under the Endangered Species Act (ESA), or other areas of biological concern...
Fine-Scale Environmental Indicators of Public Health and Well-Being for Urban Communities
Urban ecosystem services contribute to public health and well-being by buffering natural and man-made hazards, and by promoting healthful lifestyles that include physical activity, social interaction, and engagement with nature. As part of the EnviroAtlas online mapping tool, EP...
Wang, Jingrui; Tang, Wei; Zheng, Yongna; Xing, Zhuqing; Wang, Yanping
2016-09-01
A novel lactic acid bacteria strain Lactobacillus kefiranofaciens ZW3 exhibited the characteristics of high production of exopolysaccharide (EPS). The epsN gene, located in the eps gene cluster of this strain, is associated with EPS biosynthesis. Bioinformatics analysis of this gene was performed. The conserved domain analysis showed that the EpsN protein contained MATE-Wzx-like domains. Then the epsN gene was amplified to construct the recombinant expression vector pMG36e-epsN. The results showed that the EPS yields of the recombinants were significantly improved. By determining the yields of EPS and intracellular polysaccharide, it was considered that epsN gene could play its Wzx flippase role in the EPS biosynthesis. This is the first time to prove the effect of EpsN on L. kefiranofaciens EPS biosynthesis and further prove its functional property.
von Haehling, Stephan; Gremmler, Uwe; Krumm, Michael; Mibach, Frank; Schön, Norbert; Taggeselle, Jens; Dahm, Johannes B; Angermann, Christiane E
2017-06-01
Iron deficiency (ID) and anaemia are common in heart failure (HF). The prospective, observational PReP registry (Prävalenz des Eisenmangels bei Patienten mit Herzinsuffizienz) studied prevalence and clinical impact of ID and anaemia in HF outpatients attending cardiology practices in Germany. A total of 42 practices enrolled consecutive patients with chronic HF [left ventricular ejection fraction (LVEF) ≤45%]. ID was defined as serum ferritin <100 µg/l, or serum ferritin ≥100 µg/l/<300 µg/l plus transferrin saturation <20%, and anaemia as haemoglobin <13 g/dl (12 g/dl) in men (women). Exercise capacity was assessed using spiroergometry (69.4%) or 6-min walk test (30.4%). Amongst 1198 PReP-participants [69.0 ± 10.6 years, 25.3% female, New York Heart Association (NYHA) class 2.4 ± 0.5, LVEF 35.3 ± 7.2%], ID was found in 42.5% (previously unknown in all), and anaemia in 18.9% (previously known in 4.8%). ID was associated with female gender, lower body weight and haemoglobin, higher NYHA class and natriuretic peptide (NP) levels (all p < 0.05). ID was also more common in anaemic than non-anaemic patients (p < 0.0001), and 9.8% of PrEP-participants had both, ID and anaemia. On spiroergometry, ID independently predicted maximum exercise capacity even after multivariable adjustment, including anaemia (p = 0.0004). In all PrEP-participants, ID predicted reduced physical performance (adjusted for age, gender, anaemia, serum creatinine, C-reactive protein, LVEF, and NP level). Despite high prevalence, ID was previously unknown in all PrEP-participants, and anaemia was often unappreciated. Given the clinical relevance, treatability, and independent association with reduced physical performance, ID should be considered more in real-world ambulatory healthcare settings and ID-screening be advocated to cardiologists in such populations.
EpsA is an essential gene in exopolysaccharide production in Lactobacillus johnsonii FI9785.
Dertli, Enes; Mayer, Melinda J; Colquhoun, Ian J; Narbad, Arjan
2016-07-01
Lactobacillus johnsonii FI9785 has an eps gene cluster which is required for the biosynthesis of homopolymeric exopolysaccharides (EPS)-1 and heteropolymeric EPS-2 as a capsular layer. The first gene of the cluster, epsA, is the putative transcriptional regulator. In this study we showed the crucial role of epsA in EPS biosynthesis by demonstrating that deletion of epsA resulted in complete loss of both EPS-1 and EPS-2 on the cell surface. Plasmid complementation of the epsA gene fully restored EPS production, as confirmed by transmission electron microscopy and nuclear magnetic resonance (NMR) analysis. Furthermore, this complementation resulted in a twofold increase in the expression levels of this gene, which almost doubled amounts of EPS production in comparison with the wild-type strain. Analysis of EPS by NMR showed an increased ratio of the heteropolysaccharide to homopolysaccharide in the complemented strain and allowed identification of the acetylated residue in EPS-2 as the (1,4)-linked βGlcp unit, with the acetyl group located at O-6. These findings indicate that epsA is a positive regulator of EPS production and that EPS production can be manipulated by altering its expression. © 2015 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.
2011-01-01
normalized to parallel controls. Flow Cytometry and Confocal Microscopy Upon exposure to 10-ns EP, aliquots of the cellular suspension were added to a tube...Survival data was processed and plotted using GrapherH software (Golden Software, Golden, Colorado). Flow cytometry results were processed in C6 software...Accuri Cytometers, Inc., Ann Arbor, MI) and FCSExpress software (DeNovo Software, Los Angeles, CA). Final analysis and presentation of flow cytometry
PREFACE: The EPS High Energy Particle Physics Conference
NASA Astrophysics Data System (ADS)
Barlow, Roger
2008-03-01
HEPP2007, the EPS High Energy Particle Physics Conference, was held in Manchester from July 19-26 2007. It brought together 580 delegates across the whole subject: from string theorists to detector technologists, from young postgraduate students to senior professors. Geographically they came from the UK, from the rest of Europe, from North America, and from the rest of the world. It covered the whole spectrum of the subject, not only accelerator-based experiments but also its astrophysical and cosmological aspects. The parallel and plenary talks can be found in these proceedings. A key feature of the conference, as always, was the award of the prizes: this year the EPS prize was awarded to Makoto Kobayashi and Toshihide Maskawa for their explanation of CP violation with a 6 quark model—Kobayashi came to accept it in person. The Gribov medal went to Niklas Beisert, the outreach prize to Richard Jacobsson and Charles Timmermans and the Young Physicist prizer to I Furic, G Gomez-Ceballos and S Menzemer. Parallel sessions were held in Manchester University, and plenary talks were held in the Bridgewater Hall in Manchester Town centre, a magnificent modern venue whose positive and co-operative staff enabled the conference to make the most of the impressive surroundings. We were able to put the hall to its proper purpose one evening with a concert by the Fairey Band—one of the distinctive brass bands who form part of the rich musical tradition of the North of England, and came as something new and different to many of the delegates. The conference ran smoothly and successfully, thanks largely to hard work by the local organising committee who devoted a lot of time to planning, producing ideas, and anticipating potential problems. Many of them were not from Manchester itself but from other universities and laboratories in the North of England, so their dedication was especially appreciated. The EPS committee also played a major part, by the selection of plenary speakers to produce a schedule which was not only balanced but also stimulating and exciting. The speakers themelves, in both the plenary and parallel sessions, not only gave us a fine selection of interesting talks but also kept to their allotted times. Photos of many of the events can be found on the web page, http://www.hep.man.ac.uk/HEP2007 The biennial EPS HEPP conference has a long tradition as one of the major international conferences in particle physics. We were proud to be following in the succession of notable conferences, most recently at Aachen in 2003 and Lisbon in 2005: proud and also somewhat apprehensive as to whether we would come up to their high standard. With hindsight we can claim that we did just that, both in the standards of the scientific sessions and in the smooth running of an enjoyable conference. We achieved our goal of a conference that was memorable—for the right reasons. The next EPS HEPP conference is in Krakow in 2009, and is eagerly anticipated by all those who were at Manchester. We wish the organisers well. Roger Barlow Editor Conference logo
Bezawada, J; Hoang, N V; More, T T; Yan, S; Tyagi, N; Tyagi, R D; Surampalli, R Y
2013-10-15
Growth profile and extracellular polymeric substances (EPS) production of Serratia sp.1 was studied in shake flask fermentation for 72 h using wastewater sludge as raw material. Maximum cell concentration of 6.7 × 10(9) cfu/mL was obtained at 48 h fermentation time. EPS dry weight, flocculation activity and dewaterability of different EPS (tightly bound or TB-EPS, loosely bound or LB-EPS and broth-EPS or B-EPS) were also measured. The highest concentration of LB-EPS (2.45 g/L) and TB-EPS (0.99 g/L) were attained at 48 h of fermentation. Maximum flocculation activity and dewaterability (ΔCST) of TB-EPS (76.4%, 14.5s and 76.5%, 15.5s), LB-EPS (67.8%, 8.1s and 64.7%, 7.6s) and broth EPS (61%, 6.1s and 70.4%, 6.8s) were obtained at 36 and 48 h of growth. Higher flocculation activity and dewaterability were achieved with TB-EPS than with the two other EPS. Characterization of TB-EPS and LB-EPS was done in terms of their protein and carbohydrate content. Protein content was much higher in TB-EPS where as carbohydrate content was only slightly higher in TB-EPS than LB-EPS. Morphology of the Serratia strain after fermentation in sludge and TSB was observed under a scanning electron microscope and the cell size was found to be bigger in the sludge medium than the TSB medium. Copyright © 2013 Elsevier Ltd. All rights reserved.
Prostaglandin E2 regulates melanocyte dendrite formation through activation of PKCζ
Scott, Glynis; Fricke, Alex; Fender, Anne; McClelland, Lindy; Jacobs, Stacey
2007-01-01
Prostaglandins are lipid signaling intermediates released by keratinocytes in response to ultraviolet irradiation (UVR) in the skin. The main prostaglandin released following UVR is PGE2, a ligand for 4 related G-protein coupled receptors (EP1, EP2, EP3 and EP4). Our previous work established that PGE2 stimulates melanocyte dendrite formation through activation of the EP1 and EP3 receptors. The purpose of the present report is to define the signaling intermediates involved in EP1 and EP3-dependent dendrite formation in human melanocytes. We recently showed that activation of the atypical PKCζ isoform stimulates melanocyte dendricity in response to treatment with lysophosphatidylcholine. We therefore examined the potential contribution of PKCζ activation on EP1 and EP3-dependent dendrite formation in melanocytes. Stimulation of the EP1 and EP3 receptors by selective agonists activated PKCζ, and inhibition of PKCζ activation abrogated EP1 and EP3-receptor mediated melanocyte dendricity. Because of the importance of Rho-GTP binding proteins in the regulation of melanocyte dendricity, we also examined the effect of EP1 and EP3 receptor activation on Rac and Rho activity. Neither Rac nor Rho was activated upon treatment with EP1,3-receptor agonists. We show that melanocytes express only the EP3A1 isoform, but not the EP3B receptor isoform, previously associated with Rho activation, consistent with a lack of Rho stimulation by EP3 agonists. Our data suggest that PKCζ activation plays a predominant role in regulation of PGE2-dependent melanocyte dendricity. PMID:17850789
NASA Astrophysics Data System (ADS)
Li, Na; Wei, Dong; Sun, Qunqun; Han, Xiao; Du, Bin; Wei, Qin
2018-02-01
In this study, methylene blue (MB) wastewater was biotreated by anaerobic granular sludge (AnGS), and the fluorescent components of extracellular polymeric substances (EPS) and complexation mechanism were evaluated. Based on the experimental data, the sorption of MB by both live and inactivated AnGS followed the pseudo-second-order model, and the adsorption isotherm conformed well to the Langmuir model. It was shown that the difference in the sorption of live and inactivated AnGS was not significant, indicating that the sorption is mainly a physical-chemical process and metabolically mediated diffusion is negligible. The interaction between EPS and MB was proved by three-dimensional excitation-emission matrix (3D-EEM) and synchronous fluorescence spectra. 3D-EEM indicated that protein (PN)-like substances were the main peaks of EPS, and gradually quenched with increase of MB concentrations. According to synchronous fluorescence spectra, the main fluorescence quenching was caused by PN-like and humic-like fractions, and belonged to the static type of quenching. FTIR spectra demonstrated that hydroxyl and amino groups played a major role in MB sorption.
Grant, Robert M; Smith, Dawn K
2015-12-01
Best practices for integrating human immunodeficiency virus (HIV) testing and antiretroviral interventions for prevention and treatment are suggested based on research evidence and existing normative guidance. The goal is to provide high-impact prevention services during periods of substantial risk. Antiretroviral medications are recommended for postexposure prophylaxis (PEP), pre-exposure prophylaxis (PrEP), and treatment of HIV infection. We reviewed research evidence and current normative guidelines to identify best practices for integrating these high-impact prevention strategies. More sensitive HIV tests used for screening enable earlier diagnosis and treatment of HIV infection, more appropriate counseling, and help limit drug resistance. A fully suppressive PEP regimen should be initiated based on exposure history or physical findings when sensitive diagnostic testing is delayed or not available and antibody tests are negative. Transitions from PEP to PrEP are often warranted because HIV exposure events may continue to occur. This algorithmic approach to integrating PEP, PrEP, and early treatment decisions may increase the uptake of these interventions by a greater number and diversity of knowledgeable healthcare providers.
Grant, Robert M.; Smith, Dawn K.
2015-01-01
Best practices for integrating human immunodeficiency virus (HIV) testing and antiretroviral interventions for prevention and treatment are suggested based on research evidence and existing normative guidance. The goal is to provide high-impact prevention services during periods of substantial risk. Antiretroviral medications are recommended for postexposure prophylaxis (PEP), pre-exposure prophylaxis (PrEP), and treatment of HIV infection. We reviewed research evidence and current normative guidelines to identify best practices for integrating these high-impact prevention strategies. More sensitive HIV tests used for screening enable earlier diagnosis and treatment of HIV infection, more appropriate counseling, and help limit drug resistance. A fully suppressive PEP regimen should be initiated based on exposure history or physical findings when sensitive diagnostic testing is delayed or not available and antibody tests are negative. Transitions from PEP to PrEP are often warranted because HIV exposure events may continue to occur. This algorithmic approach to integrating PEP, PrEP, and early treatment decisions may increase the uptake of these interventions by a greater number and diversity of knowledgeable healthcare providers. PMID:26512356
Check the Head: Emergency Ultrasound Diagnosis of Fetal Anencephaly
Hall, John W.; Denne, Nicolas; Minardi, Joseph J.; Williams, Debra; Balcik, BJ
2016-01-01
Background Early pregnancy complaints in emergency medicine are common. Emergency physicians (EP) increasingly employ ultrasound (US) in the evaluation of these complaints. As a result, it is likely that rare and important diagnoses will be encountered. We report a case of fetal anencephaly diagnosed by bedside emergency US in a patient presenting with first-trimester vaginal bleeding. Case Report A 33-year-old patient at 10 weeks gestation presented with vaginal bleeding. After initial history and physical examination, a bedside US was performed. The EP noted the abnormal appearance of the fetal cranium and anencephaly was suspected. This finding was confirmed by a consultative high-resolution fetal US. Making the diagnosis at the point of care allowed earlier detection and more comprehensive maternal counseling about pregnancy options. This particular patient underwent elective abortion which was able to be performed at an earlier gestation, thus decreasing maternal risk. If this diagnosis would not have been recognized by the EP at the point of care, it may not have been diagnosed until the second trimester, and lower-risk maternal options would not have been available. PMID:27429697
The Plasma Archipelago: Plasma Physics in the 1960s
NASA Astrophysics Data System (ADS)
Weisel, Gary J.
2017-09-01
With the foundation of the Division of Plasma Physics of the American Physical Society in April 1959, plasma physics was presented as the general study of ionized gases. This paper investigates the degree to which plasma physics, during its first decade, established a community of interrelated specialties, one that brought together work in gaseous electronics, astrophysics, controlled thermonuclear fusion, space science, and aerospace engineering. It finds that, in some regards, the plasma community was indeed greater than the sum of its parts and that its larger identity was sometimes glimpsed in inter-specialty work and studies of fundamental plasma behaviors. Nevertheless, the plasma specialties usually worked separately for two inter-related reasons: prejudices about what constituted "basic physics," both in the general physics community and within the plasma community itself; and a compartmentalized funding structure, in which each funding agency served different missions.
Derivation of global vegetation biophysical parameters from EUMETSAT Polar System
NASA Astrophysics Data System (ADS)
García-Haro, Francisco Javier; Campos-Taberner, Manuel; Muñoz-Marí, Jordi; Laparra, Valero; Camacho, Fernando; Sánchez-Zapero, Jorge; Camps-Valls, Gustau
2018-05-01
This paper presents the algorithm developed in LSA-SAF (Satellite Application Facility for Land Surface Analysis) for the derivation of global vegetation parameters from the AVHRR (Advanced Very High Resolution Radiometer) sensor on board MetOp (Meteorological-Operational) satellites forming the EUMETSAT (European Organization for the Exploitation of Meteorological Satellites) Polar System (EPS). The suite of LSA-SAF EPS vegetation products includes the leaf area index (LAI), the fractional vegetation cover (FVC), and the fraction of absorbed photosynthetically active radiation (FAPAR). LAI, FAPAR, and FVC characterize the structure and the functioning of vegetation and are key parameters for a wide range of land-biosphere applications. The algorithm is based on a hybrid approach that blends the generalization capabilities offered by physical radiative transfer models with the accuracy and computational efficiency of machine learning methods. One major feature is the implementation of multi-output retrieval methods able to jointly and more consistently estimate all the biophysical parameters at the same time. We propose a multi-output Gaussian process regression (GPRmulti), which outperforms other considered methods over PROSAIL (coupling of PROSPECT and SAIL (Scattering by Arbitrary Inclined Leaves) radiative transfer models) EPS simulations. The global EPS products include uncertainty estimates taking into account the uncertainty captured by the retrieval method and input errors propagation. A sensitivity analysis is performed to assess several sources of uncertainties in retrievals and maximize the positive impact of modeling the noise in training simulations. The paper discusses initial validation studies and provides details about the characteristics and overall quality of the products, which can be of interest to assist the successful use of the data by a broad user's community. The consistent generation and distribution of the EPS vegetation products will constitute a valuable tool for monitoring of earth surface dynamic processes.
Kene, Mamata V.; Ballard, Dustin W.; Vinson, David R.; Rauchwerger, Adina S.; Iskin, Hilary R.; Kim, Anthony S.
2015-01-01
Introduction We evaluated emergency physicians’ (EP) current perceptions, practice, and attitudes towards evaluating stroke as a cause of dizziness among emergency department patients. Methods We administered a survey to all EPs in a large integrated healthcare delivery system. The survey included clinical vignettes, perceived utility of historical and exam elements, attitudes about the value of and requisite post-test probability of a clinical prediction rule for dizziness. We calculated descriptive statistics and post-test probabilities for such a clinical prediction rule. Results The response rate was 68% (366/535). Respondents’ median practice tenure was eight years (37% female, 92% emergency medicine board certified). Symptom quality and typical vascular risk factors increased suspicion for stroke as a cause of dizziness. Most respondents reported obtaining head computed tomography (CT) (74%). Nearly all respondents used and felt confident using cranial nerve and limb strength testing. A substantial minority of EPs used the Epley maneuver (49%) and HINTS (head-thrust test, gaze-evoked nystagmus, and skew deviation) testing (30%); however, few EPs reported confidence in these tests’ bedside application (35% and 16%, respectively). Respondents favorably viewed applying a properly validated clinical prediction rule for assessment of immediate and 30-day stroke risk, but indicated it would have to reduce stroke risk to <0.5% to be clinically useful. Conclusion EPs report relying on symptom quality, vascular risk factors, simple physical exam elements, and head CT to diagnose stroke as the cause of dizziness, but would find a validated clinical prediction rule for dizziness helpful. A clinical prediction rule would have to achieve a 0.5% post-test stroke probability for acceptability. PMID:26587108
How can laboratory plasma experiments contribute to space and &astrophysics?
NASA Astrophysics Data System (ADS)
Yamada, M.
Plasma physics plays key role in a wide range of phenomena in the universe, from laboratory plasmas to the magnetosphere, the solar corona, and to the tenuous interstellar and intergalactic gas. Despite the huge difference in physical scales, there are striking similarities in plasma behavior of laboratory and space plasmas. Similar plasma physics problems have been investigated independently by both laboratory plasma physicists and astrophysicists. Since 1991, cross fertilization has been increased among laboratory plasma physicists and space physicists through meeting such as IPELS [Interrelationship between Plasma Experiments in the Laboratory and Space] meeting. The advances in laboratory plasma physics, along with the recent surge of astronomical data from satellites, make this moment ripe for research collaboration to further advance plasma physics and to obtain new understanding of key space and astrophysical phenomena. The recent NRC review of astronomy and astrophysics notes the benefit that can accrue from stronger connection to plasma physics. The present talk discusses how laboratory plasma studies can contribute to the fundamental understandings of the space and astrophysical phenomena by covering common key physics topics such as magnetic reconnection, dynamos, angular momentum transport, ion heating, and magnetic self-organization. In particular, it has recently been recognized that "physics -issue- dedicated" laboratory experiments can contribute significantly to the understanding of the fundamental physics for space-astrophysical phenomena since they can create fundamental physics processes in controlled manner and provide well-correlated plasma parameters at multiple plasma locations simultaneously. Such dedicated experiments not only can bring about better understanding of the fundamental physics processes but also can lead to findings of new physics principles as well as new ideas for fusion plasma confinement. Several dedicated experiments have provided the fundamental physics data for magnetic reconnection [1]. Linear plasma devices have been utilized to investigate Whistler waves and Alfven wave phenomena [2,3]. A rotating gallium disk experiment has been initiated to study magneto-rotational instability [4]. This talk also presents the most recent progress of these dedicated laboratory plasma research. 1. M. Yamada et al., Phys. Plasmas 4, 1936, (1997) 2. R. Stenzel, Phys. Rev. Lett. 65, 3001 (1991) 3. W. Gekelman et al, Plasma Phys. Contr. Fusion, v42, B15-B26, Suppl.12B (2000) 4. H. Ji, J. Goodman, A. Kageyama Mon. Not. R. Astron. Soc. 325, L1- (2001)
Rendina, H. Jonathon; Grov, Christian
2017-01-01
Gay, bisexual, and other men who have sex with men (GBM) are disproportionately affected by the HIV epidemic. Despite the promise of pre-exposure prophylaxis (PrEP) in reducing HIV transmission risk, barriers for uptake and persistence exist. We sought to identify whether GBM in a nationwide cohort who have not yet initiated PrEP (n = 906) would prefer to get PrEP-related care from a primary care provider (PCP) compared to a specialist clinic or provider. We then sought to identify their level of interest and factors associated with preference for using home-based PrEP services (i.e., HB-PrEP), defined to participants as conducting HIV/STI self-testing from home with PrEP prescription mailing after an initial in-person clinic visit. We examined the associations of demographics, sexual HIV transmission risk, concern about frequent medical checkups associated with PrEP, health care access, and PrEP intentions with preferences for healthcare provider type and HB-PrEP. Concern about frequent medical checkups were associated with preferring a PCP for PrEP-related care, but men who perceived a barrier to bringing up the topic of PrEP with a doctor preferred a specialist clinic or provider more than a PCP. HB-PrEP was more appealing for younger men and those engaged in sexual HIV transmission risk, suggesting HB-PrEP could help reach GBM most vulnerable to HIV and in need of PrEP. HB-PrEP expansion has potential to increase PrEP uptake and persistence among GBM, particularly for men with barriers to clinic-based care and higher intentions to initiate PrEP. Clinical guidelines regarding HB-PrEP are needed to expand its use. PMID:29281688
Prostaglandin E2 modulates dendritic cell function via EP2 and EP4 receptor subtypes.
Harizi, Hedi; Grosset, Christophe; Gualde, Norbert
2003-06-01
We have reported previously that PGE(2) inhibits dendritic cells (DC) functions. Because E prostanoid receptor (EPR) subtypes involved in this action are unknown, expression and functions of these receptors were examined in DC. Western blot and flow cytometry analyses showed that all EPRs were coexpressed in DC. In a dose-dependent manner, lipopolysaccharide (LPS) enhanced EP(2)R/EP(4)R but not EP(1)R/EP(3)R expressions. NS-398, a cyclooxygenase (COX)-2-selective inhibitor, suppressed LPS-enhanced EP(2)R/EP(4)R expression, suggesting that COX-2-issued prostaglandin E(2) (PGE(2)) modulates DC function through stimulation of specific EPR subtypes. Using selective agonists, we found that butaprost, an EP(2)R agonist, and PGE(1) alcohol, an EP(2)R and EP(2)R/EP(4)R agonist, inhibited major histocompatibility complex class II expression and enhanced interleukin-10 production from DC. However, no effect was observed with sulprostone and 17-phenyl-omega-trinor-PGE(2), selective agonists for EP(1)R and EP(1)R/EP(3)R, respectively. Treatment of DC with dibutyryl cyclic adenosine monophosphate (cAMP), an analog of cAMP, mimics PGE(2)-induced, inhibitory effects. Taken together, our data demonstrate that EP(2)R/EP(4)R are efficient for mediating PGE(2)-induced modulation of DC functions.
NASA Astrophysics Data System (ADS)
Xu, Zimu; Shen, Jie; Cheng, Cheng; Hu, Shuheng; Lan, Yan; Chu, Paul K.
2017-03-01
The antimicrobial effects and associated mechanism of inactivation of Staphylococcus aureus (S. aureus) NCTC-8325 biofilms induced by a He/O2 atmospheric-pressure plasma jet (APPJ) are investigated in vitro. According to CFU (colony forming units) counting and the resazurin-based assay, the 10 min He/O2 (0.5%) APPJ treatment produces the optimal inactivation efficacy (>5 log10 ml-1) against the S. aureus biofilm and 5% of the bacteria enter a viable but non-culturable (VBNC) state. Meanwhile, 94% of the bacteria suffer from membrane damage according to SYTO 9/PI counterstaining. Scanning electron microscopy (SEM) reveals that plasma exposure erodes the extracellular polymeric substances (EPS) and then the cellular structure. The H2DCFDA-stained biofilms show larger concentrations of intracellular reactive oxygen species (ROS) in membrane-intact bacteria with increasing plasma dose. The admixture of oxygen in the working gas highly contributes to the deactivation efficacy of the APPJ against S. aureus and the plasma-induced endogenous ROS may work together with the discharge-generated ROS to continuously damage the bacterial membrane structure leading to deactivation of the biofilm microbes.
Zhen, Guang-Yin; Lu, Xue-Qin; Li, Yu-You; Zhao, You-Cai
2013-05-01
The feasibility of electrolysis integrated with Fe(II)-activated persulfate (S2O8(2-)) oxidation to improve waste activated sludge (WAS) dewaterability was evaluated. The physicochemical properties (sludge volume (SV), total suspended solids (TSS) and volatile suspended solids (VSS)) and extracellular polymeric substances (EPS), including slime EPS, loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS) were characterized to identify their exact roles in sludge dewatering. While dewaterability negatively corresponded to LB-EPS, TB-EPS, protein (PN) and polysaccharide (PS) in LB-EPS and TB-EPS, it was independent of SV, TSS, VSS, slime EPS and PN/PS. Further study through scanning electron microscope (SEM) verified the entrapment of bacterial cells by TB-EPS, protecting them against electrolysis disruption. Comparatively, electrolysis integrated with S2O8(2-)/Fe(II) oxidation was able to effectively disrupt the protective barrier and crack the entrapped cells, releasing the water inside EPS and cells. Therefore, the destruction of both TB-EPS and cells is the fundamental reason for the enhanced dewaterability. Copyright © 2013 Elsevier Ltd. All rights reserved.
Li, X Y; Yang, S F
2007-03-01
Laboratory experiments on the activated sludge (AS) process were carried out to investigate the influence of microbial extracellular polymeric substances (EPS), including loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS), on biomass flocculation, sludge settlement and dewaterability. The heat EPS extraction method was modified to include a mild step and a harsh step for extracting the LB-EPS and TB-EPS, respectively, from the sludge suspension. Six lab-scale AS reactors were used to grow AS with different carbon sources of glucose and sodium acetate, and different sludge retention times (SRTs) of 5, 10 and 20 days. The variation in the bioreactor condition produced sludge with different abundances of EPS and different flocculation and separation characteristics. The sludge that was fed on glucose had more EPS than the sludge that was fed on acetate. For any of the feeding substrates, the sludge had a nearly consistent TB-EPS value regardless of the SRT, and an LB-EPS content that decreased with the SRT. The acetate-fed sludge performed better than the glucose-fed sludge in terms of bioflocculation, sludge sedimentation and compression, and sludge dewaterability. The sludge flocculation and separation improved considerably as the SRT lengthened. The results demonstrate that the LB-EPS had a negative effect on bioflocculation and sludge-water separation. The parameters for the performance of sludge-water separation were much more closely correlated with the amount of LB-EPS than with the amount of TB-EPS. It is argued that although EPS is essential to sludge floc formation, excessive EPS in the form of LB-EPS could weaken cell attachment and the floc structure, resulting in poor bioflocculation, greater cell erosion and retarded sludge-water separation.
Valenzuela, R; Li, C H; Huidobro-Toro, J P
1991-08-01
The inhibitory opioid activities of beta h-endorphin (beta h-EP), its structurally related peptide analogues [Gln8,Gly31]-beta h-EP-Gly-Gly-NH2 (Gly-Gly-beta h-EP), [Arg9,19,24,28,29]-beta h-EP (Arg-beta h-EP) and methionine enkephalin have been examined in the electrically stimulated mouse vas deferens bioassay. All four peptides behaved as full agonists; methionine enkephalin was the most potent followed by Arg-beta h-EP, beta h-EP and Gly-Gly-beta h-EP. Neither Gly-Gly-beta h-EP nor Arg-beta h-EP antagonized the inhibitory action of beta h-EP or methionine enkephalin. An hour of tissue exposure to 30 nM beta-funaltrexamine followed by thorough washing, displaced to the right, in a parallel fashion, the concentration-response curves of beta h-EP and analogues. Whereas the displacement of the concentration response curves was 8 to 10-fold for beta h-EP and Arg-beta h-EP, it was only about 3-fold for Gly-Gly-beta h-EP and methionine enkephalin. Naltrindole was the most potent antagonist of methionine enkephalin with an apparent pA2 of 9.4; its potency as an antagonist of beta h-EP and related analogues was approximately one-tenth of this with pA2 values approximately 8.5. Norbinaltorphimine also antagonized the action of the opioid peptides with pA2 values close to 7.8.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yanez, M.E.; Korotkov, K.V.; Abendroth, J.
2009-05-28
Type II secretion systems (T2SS) translocate virulence factors from the periplasmic space of many pathogenic bacteria into the extracellular environment. The T2SS of Vibrio cholerae and related species is called the extracellular protein secretion (Eps) system that consists of a core of multiple copies of 11 different proteins. The pseudopilins, EpsG, EpsH, EpsI, EpsJ and EpsK, are five T2SS proteins that are thought to assemble into a pseudopilus, which is assumed to interact with the outer membrane pore, and may actively participate in the export of proteins. We report here biochemical evidence that the minor pseudopilins EpsI and EpsJ frommore » Vibrio species interact directly with one another. Moreover, the 2.3 {angstrom} resolution crystal structure of a complex of EspI and EpsJ from Vibrio vulnificus represents the first atomic resolution structure of a complex of two different pseudopilin components from the T2SS. Both EpsI and EpsJ appear to be structural extremes within the family of type 4a pilin structures solved to date, with EpsI having the smallest, and EpsJ the largest, 'variable pilin segment' seen thus far. A high degree of sequence conservation in the EpsI:EpsJ interface indicates that this heterodimer occurs in the T2SS of a large number of bacteria. The arrangement of EpsI and EpsJ in the heterodimer would correspond to a right-handed helical character of proteins assembled into a pseudopilus.« less
Zimet, Gregory; Lally, Michelle; Kahn, Jessica A.
2016-01-01
Abstract Oral pre-exposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) prevention is currently indicated for use in adults in the United States and may soon be indicated for minor adolescents. However, implementation of PrEP use among minors may present unique barriers. We conducted 15 individual, semi-structured interviews among US clinicians caring for HIV-infected and at-risk youth. The theory-driven interview guide assessed demographics, perceived role of oral PrEP in HIV prevention among adolescents, perceived barriers to and facilitating factors for use of PrEP in adolescents, and clinician-reported likelihood of prescribing PrEP. Transcripts were analyzed using framework analysis. Overall, clinicians viewed PrEP as a time-limited intervention that is one part of a comprehensive approach to HIV prevention among adolescents. Perceived barriers to prescribing to minors included concerns about: confidentiality, legality of minors consenting to PrEP without parental involvement, ability of minors to understand the risks/benefits of PrEP, the possible impact of PrEP on bone accrual, off-label use of PrEP medication in minors, and the high costs associated with PrEP use. Clinician-reported facilitating factors for prescribing PrEP to youth included educating communities and other clinicians about PrEP, ensuring adequate financial resources and infrastructure for delivering PrEP, developing formal guidance on effective behavioral interventions that should be delivered with PrEP, and gaining personal experience with prescribing PrEP. Clinicians indicated greater comfort with prescribing PrEP to adults versus minors. For PrEP to become more widely available to youth at risk for HIV infection, barriers that are unique to PrEP use in minors must be addressed. PMID:27410497
Magnus, Manya; Mayer, Kenneth H.; Krakower, Douglas S.; Eldahan, Adam I.; Hawkins, Lauren A. Gaston; Underhill, Kristen; Hansen, Nathan B.; Kershaw, Trace S.; Betancourt, Joseph R.; Dovidio, John F.
2017-01-01
Abstract Despite the demonstrated effectiveness of HIV pre-exposure prophylaxis (PrEP) and evidence that most PrEP users do not engage in risk compensation (i.e., increased risk behavior due to a perceived decrease in HIV susceptibility), some healthcare providers report patient risk compensation to be a deterrent to prescribing PrEP. Overcoming this barrier is essential to supporting PrEP access and uptake among people at risk for HIV. To inform such efforts, this qualitative study explored PrEP-related risk compensation attitudes among providers with firsthand experience prescribing PrEP. US-based PrEP providers (n = 18), most of whom were HIV specialists, were recruited through direct outreach and referral from colleagues and other participants. Individual 90-min semistructured interviews were conducted by phone or in person from September 2014 through February 2015, transcribed, and thematically analyzed. Three attitudinal themes emerged: (1) providers' role is to support patients in making informed decisions, (2) risk behavior while taking PrEP does not fully offset PrEP's protective benefit (i.e., PrEP confers net protection, even with added behavioral risk), and (3) PrEP-related risk compensation is unduly stigmatized within and beyond the healthcare community. Participants were critical of other healthcare providers' negative judgment of patients and reluctance to prescribe PrEP due to anticipated risk compensation. Several providers also acknowledged an evolution in their thinking from initial ambivalence toward greater acceptance of PrEP and PrEP-related behavior change. PrEP providers' insights about risk compensation may help to address unsubstantiated concerns about PrEP-related risk compensation and challenge the acceptability of withholding PrEP on these grounds. PMID:28414261
Proton probing of a relativistic laser interaction with near-critical plasma
NASA Astrophysics Data System (ADS)
Willingale, Louise; Zulick, C.; Thomas, A. G. R.; Maksimchuk, A.; Krushelnick, K.; Nilson, P. M.; Stoeckl, C.; Sangster, T. C.; Nazarov, W.
2014-10-01
The Omega EP laser (1000 J in 10 ps pulses) was used to investigate a relativistic intensity laser interaction with near-critical density plasma using a transverse proton beam to diagnose the large electromagnetic fields generated. A very low density foam target mounted in a washer provided the near-critical density conditions. The fields from a scaled, two-dimensional particle-in-cell simulation were inputed into a particle-tracking code to create simulated proton probe images. This allows us to understand the origins of the complex features in the experimental images, including a rapidly expanding sheath field, evidence for ponderomotive channeling and fields at the foam-washer interface. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0002028.
von der Emde, Laura; Goltz, Diane; Latz, Stefan; Müller, Stefan C; Kristiansen, Glen; Ellinger, Jörg; Syring, Isabella
2014-01-01
Prostaglandins, especially prostaglandin E2 (PGE2), and COX-2 play an important role in carcinogenesis of many tumors including bladder cancer (BCA). The PGE2 receptors EP1-4 regulate tumor cell growth, invasion and migration in different tumor entities but EP expression in BCA remains to be determined. In the present study we examined the expression of EP1-4 in non-muscle invasive bladder cancer (NMIBC), muscle invasive bladder cancer (MIBC) and normal urothelial tissue (NU) using immunohistochemistry. Nuclear and cytoplasmic EP1-4 expression was correlated with clinicopathological parameters and survival of BCA patients. EP1, EP2 and EP3 were significantly less expressed in the cytoplasm und nucleus of NMIBC and MIBC than in NU; EP4 cytoplasmic staining in MIBC was significantly higher compared to NU. The cytoplasmic staining was significantly more abundant in MIBC than in NMIBC in all investigated receptors except EP2. The level of EP staining in NMIBC was correlated with staging and grading, especially cytoplasmic EP1. Nuclear staining of EP1 was an independent predictor of BCA recurrence-free survival in NMIBC patients. EP receptors are dysregulated in BCA. The increase of EP1 may be used as prognostic parameter in NMIBC patients and its dysregulation could be targeted by specific EP1 inhibitors.
von der Emde, Laura; Goltz, Diane; Latz, Stefan; Müller, Stefan C; Kristiansen, Glen; Ellinger, Jörg; Syring, Isabella
2014-01-01
Prostaglandins, especially prostaglandin E2 (PGE2), and COX-2 play an important role in carcinogenesis of many tumors including bladder cancer (BCA). The PGE2 receptors EP1-4 regulate tumor cell growth, invasion and migration in different tumor entities but EP expression in BCA remains to be determined. In the present study we examined the expression of EP1-4 in non-muscle invasive bladder cancer (NMIBC), muscle invasive bladder cancer (MIBC) and normal urothelial tissue (NU) using immunohistochemistry. Nuclear and cytoplasmic EP1-4 expression was correlated with clinicopathological parameters and survival of BCA patients. EP1, EP2 and EP3 were significantly less expressed in the cytoplasm und nucleus of NMIBC and MIBC than in NU; EP4 cytoplasmic staining in MIBC was significantly higher compared to NU. The cytoplasmic staining was significantly more abundant in MIBC than in NMIBC in all investigated receptors except EP2. The level of EP staining in NMIBC was correlated with staging and grading, especially cytoplasmic EP1. Nuclear staining of EP1 was an independent predictor of BCA recurrence-free survival in NMIBC patients. EP receptors are dysregulated in BCA. The increase of EP1 may be used as prognostic parameter in NMIBC patients and its dysregulation could be targeted by specific EP1 inhibitors. PMID:25520883
Lau, Joseph T. F.; Fang, Yuan; Ip, Mary; Gross, Danielle L.
2018-01-01
Objectives This study was to investigate the prevalence of actual uptake of pre-exposure prophylaxis (PrEP), willingness to use daily oral PrEP under two cost scenarios, and potential issues related to PrEP use among men who have sex with men (MSM) with HIV negative/unknown sero-status in Hong Kong, China. Factors associated with the two measures of willingness were also investigated. Methods 403 eligible MSM completed the anonymous venue-based face-to-face interview/telephone interview. Results Only 1% had ever used PrEP. After being briefed about some facts of PrEP, the prevalence of willingness to use daily oral PrEP was 7.7% if they could purchase PrEP at private hospitals/clinics at HK$8,000 (US$1,032)/month (market rate) and 45.2% if free PrEP was provided by public hospitals/clinics in Hong Kong (free PrEP). After adjusted for significant background variables, significant factors of these two measures of willingness included: (1) number of correct responses to knowledge on PrEP, (2) perceived risk of HIV infection in the next six months, and (3) constructs of the Theory of Planned Behavior: positive and negative attitudes toward PrEP, perceived their significant others would support them take PrEP (perceived subjective norm), perceived number of local MSM who were willing to take PrEP (perceived descriptive norm), and confidence in using PrEP under the two scenarios (perceived behavioral control). Among all participants, 9.7% and 25.1% would start and discontinue using PrEP without consulting doctors; 26.0% would not take PrEP daily if it was provided for free, and 42.4% would not take up HIV testing every 3 months after using PrEP. Conclusion Different strategies should be considered for promoting PrEP at market rate and if free PrEP is made available. Future promotion should increase their knowledge about PrEP, modify their perceptions related to HIV and PrEP, and address some potential issues related to PrEP use. PMID:29432470
Wang, Zichao; Gao, Mengchun; Wang, Zhe; She, Zonglian; Chang, Qingbo; Sun, Changqing; Zhang, Jian; Ren, Yun; Yang, Ning
2013-11-01
The effect of salinity on extracellular polymeric substances (EPS) of activated sludge was investigated in an anoxic-aerobic sequencing batch reactor (SBR). The contents of loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS) were positively correlated with the salinity. The polysaccharide (PS) and protein (PN) contents in both LB-EPS and TB-EPS increased with the increase of salinity. With the increase of salinity from 0.5% to 6%, the PN/PS ratios in LB-EPS and TB-EPS decreased from 4.8 to 0.9 and from 2.9 to 1.4, respectively. The four fluorescence peaks in both LB-EPS and TB-EPS identified by three-dimensional excitation-emission matrix fluorescence spectroscopy are attributed to PN-like substances and humic acid-like substances. The Fourier transform infrared spectra of the LB-EPS and TB-EPS appeared to be very similar, but the differences across the spectra were apparent in terms of the relative intensity of some bands with the increase of salinity. The sludge volume index showed a linear correlation with LB-EPS (R(2)=0.9479) and TB-EPS (R(2)=0.9355) at different salinities, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Benthien, A.; Schulte, S.; Andersen, N.; Müller, P. J.; Schneider, R. R.
The carbon isotopic signal of the C37-alkenone, a taxon-specific biomarker for hap- tophyte algae, has been used in various paleoceanographic studies as a proxy for an- cient surface water CO2 concentration ([CO2aq]). However, a number of recent cul- ture, field and sediment studies imply that the carbon isotopic fractionation (ep) of alkenones is controlled predominantly by physiological processes and environmental factors other than the ambient CO2 concentration (i.e., growth rate, nutrient availabil- ity, light intensity, active carbon uptake, bicarbonate utilisation). The environmental conditions controlling phytoplankton growth are likely to vary strongly with oceano- graphic setting. Culture experiments can not perfectly recreate natural growth con- ditions and physical processes which affect the carbon isotopic signal in the field and its preservation in the sediment. Consequently, the use of the carbon isotopic record of alkenones as a reliable paleoceonographic proxy also requires sediment- based studies covering a broad range of different oceanic regimes for the past and modern ocean. Here, we present the first basin-wide comparison of alkenone ep val- ues from sediments of the Last Glacial Maximum (LGM) and the latest Holocene. Different oceanographic regions from the equatorial and South Atlantic Ocean were examined. Generally, alkenone ep is lower during the LGM compared to the Holocene. Considering present understanding of LGM-Holocene changes in surface water condi- tions, the observed glacial/interglacial difference in ep indicates that different effects controlled the isotopic fractionation in alkenone-producing algae depending on the regional setting. In upwelling regions, the variations in ep probably reflect a glacial increase in haptophyte productivity controlled by the availability of surface water nu- trient concentrations. By contrast, in oligotrophic areas slightly lower nutrient content was available during LGM. Here, the observed ep difference can be explained partly with an assumed glacial decrease in surface water [CO2aq]. However, it can not be ruled out that changes in haptophyte productivity also affected the ep signal to some extent. This study clearly demonstrates that a reliable reconstruction of [CO2aq] on the basis of the isotopic composition of alkenones is not feasible without a detailed 1 knowledge of ancient haptophyte growth conditions. 2
Implementing an Industrial Approach into Physics Graduate Education
NASA Astrophysics Data System (ADS)
Vickers, Ken
2006-04-01
Physics graduate education has attracted a student population with a both high independence and interest in individual professional work. These personality tendencies have been validated in the students' eyes by both the observed professional behaviors of the majority of their faculty, and by the public acceptance of the persona of ``eccentric but brilliant'' physics students. This has resulted in a self-perpetuating cycle of professionals entering the academic workplace whose interest in whole-organization optimization, as well as the skills needed to optimize organizations, are low to non-existent. But at the same time the needs of the country's technical work force, as defined by national gatherings of prominent leaders from academic, industrial, and governmental communities, continue to list human interaction ``soft skills'' as one of the most important professional traits needed by professionals in their careers. This gap between the physics graduate education and requirements needed by next generation physicists provided an opportunity for experimental approaches to graduate physics education. The University of Arkansas' Physics Department lead the formation of a new experimental approach to interdisciplinary education in the broad field of microelectronics and photonics (microEP) in 1998, resulting in the formation of a stand-alone MS/PhD microEP program. This program implemented an industrial work group approach to graduate education, and won several educational grants including a NSF IGERT and a Department of Education FIPSE. The FIPSE grant in 2001 supported the modification of the industrial work group approach for implementation by the UA physics graduate program to address the gap between national need and current education. This talk will address the key goals of this implementation, the tactics that were put in place to address the goals, and the results of this educational approach since its implementation with the Fall 2001 entering class.
Patel, Rena C; Stanford-Moore, Gaelen; Odoyo, Josephine; Pyra, Maria; Wakhungu, Imeldah; Anand, Keerthana; Bukusi, Elizabeth A; Baeten, Jared M; Brown, Joelle M
2016-01-01
Since 2015, the World Health Organization recommends pre-exposure prophylaxis (PrEP) for all persons at substantial risk for HIV, including HIV-uninfected partners in serodiscordant relationships in resource-limited settings. As PrEP moves from clinical trials to real-world use, understanding facilitators of and barriers to PrEP initiation and adherence is critical to successful PrEP implementation and rollout. We conducted 44 in-depth individual or couple interviews with 63 participants (30 without HIV and 33 with HIV) enrolled in the Partners Demonstration Project in Kisumu, Kenya, between August and September 2014. The semi-structured interviews discussed the following: 1) perceived advantages and disadvantages of antiretroviral therapy (ART)/PrEP; 2) reasons for accepting or declining ART/PrEP and 3) influence of prevention of transmission to partner or infant on ART/PrEP use. Transcripts from the interviews were iteratively analyzed using inductive content analysis. Our study identified three key factors that may facilitate initiation of PrEP in this population. First, participants using PrEP felt reduced stress and increased trust in their HIV serodiscordant relationships. Second, greater community-wide knowledge of PrEP was thought to likely increase PrEP acceptance. Third, greater education and counselling by providers on PrEP use was also considered to likely increase the adoption of PrEP. We also identified three key barriers to initiation of and adherence to PrEP. First, most participants who declined PrEP expressed doubts about the relative additional effectiveness of PrEP in combination with other prevention tools. Second, perceived stigma related to PrEP use was an important barrier to PrEP initiation. Third, many struggled with overcoming perceived side effects or logistical challenges of taking daily PrEP, particularly when they themselves were not ill. Leveraging the facilitators and overcoming barriers to PrEP uptake may enhance the successful rollout of PrEP among HIV serodiscordant couples in Kenya and other areas in sub-Saharan Africa, thereby reducing sexual transmission of HIV. Further research focused on how best to provide counselling on combination HIV prevention tools in the context of PrEP use is a crucial next step to delivering PrEP.
Schlaeger, Regina; Hardmeier, Martin; D'Souza, Marcus; Grize, Leticia; Schindler, Christian; Kappos, Ludwig; Fuhr, Peter
2016-03-01
To compare the ability of different evoked potential scores (EPS) to monitor and predict the disease course in multiple sclerosis (MS). Seventy-two patients with MS or clinically isolated syndrome were investigated by visual, motor, and somatosensory EP and expanded disability status scale (EDSS) at baseline (T0) and months 6, 12, 24, 36 (T4). EP results were rated according to ordinal (o), semi-quantitative (sq), and quantitative (q) EPS. Spearman rank correlation and multivariable linear regression were used to investigate the associations between EPS and clinical disability. All EPS correlated with EDSS cross-sectionally (0.72⩽rho⩽0.87, all p<0.001) and longitudinally (0.39⩽rho⩽0.47, all p⩽0.004). EPS(T0) and EDSS(T0) together explained 85-86% of EDSS(T4) variance. A posteriori power calculation showed that the sample sizes needed to detect significant changes over 6 months in q-EPS, sq-EPS and o-EPS with 90% certainty would be 50, 129 and 222, respectively. q-EPS change(T1-T0) correlated with EDSS change(T4-T0) (rho=0.56, p<0.001), while sq-EPS and o-EPS changes(T1-T0) did not. All three EPS allow disease course monitoring in MS. However, the quantitative EPS detects clinically relevant short-term changes with a smaller sample size than semi-quantitative or ordinal EPS. These results underscore the potential of EPS to characterize MS disease evolution. Copyright © 2016. Published by Elsevier Ireland Ltd.
This study reports on the results of work preparing 30,000 Ibs of SARM or synthetic analytical reference matrix, a surrogate Superfund soil containing a vide range of contaminants. It also reports the results ©f bench scale treatability experiments designed to simulate the EP...
Patel, Rupa R; Luke, Douglas A; Proctor, Enola K; Powderly, William G; Chan, Philip A; Mayer, Kenneth H; Harrison, Laura C; Dhand, Amar
2018-01-01
The aim of this study was to identify sex venue-based networks among men who have sex with men (MSM) to inform HIV preexposure prophylaxis (PrEP) dissemination efforts. Using a cross-sectional design, we interviewed MSM about the venues where their recent sexual partners were found. Venues were organized into network matrices grouped by condom use and race. We examined network structure, central venues, and network subgroups. Among 49 participants, the median age was 27 years, 49% were Black and 86% reported condomless anal sex (ncAS). Analysis revealed a map of 54 virtual and physical venues with an overlap in the ncAS and with condom anal sex (cAS) venues. In the ncAS network, virtual and physical locations were more interconnected. The ncAS venues reported by Blacks were more diffusely organized than those reported by Whites. The network structures of sex venues for at-risk MSM differed by race. Network information can enhance HIV prevention dissemination efforts among subpopulations, including PrEP implementation.
Luke, Douglas A.; Proctor, Enola K.; Powderly, William G.; Chan, Philip A.; Mayer, Kenneth H.; Harrison, Laura C.; Dhand, Amar
2018-01-01
Abstract Purpose: The aim of this study was to identify sex venue-based networks among men who have sex with men (MSM) to inform HIV preexposure prophylaxis (PrEP) dissemination efforts. Methods: Using a cross-sectional design, we interviewed MSM about the venues where their recent sexual partners were found. Venues were organized into network matrices grouped by condom use and race. We examined network structure, central venues, and network subgroups. Results: Among 49 participants, the median age was 27 years, 49% were Black and 86% reported condomless anal sex (ncAS). Analysis revealed a map of 54 virtual and physical venues with an overlap in the ncAS and with condom anal sex (cAS) venues. In the ncAS network, virtual and physical locations were more interconnected. The ncAS venues reported by Blacks were more diffusely organized than those reported by Whites. Conclusion: The network structures of sex venues for at-risk MSM differed by race. Network information can enhance HIV prevention dissemination efforts among subpopulations, including PrEP implementation. PMID:29324178
Interplay of Physical Mechanisms and Biofilm Processes: Review of Microfluidic Methods
Karimi, A.; Karig, D.; Kumar, A.; Ardekani, A. M.
2014-01-01
Bacteria in natural and artificial environments often reside in self-organized, integrated communities known as biofilms. Biofilms are highly structured entities consisting of bacterial cells embedded in a matrix of self-produced extracellular polymeric substances (EPS). The EPS matrix acts like a biological ‘glue’ enabling microbes to adhere to and colonize a wide range of surfaces. Once integrated into biofilms, bacterial cells can withstand various forms of stress such as antibiotics, hydrodynamic shear and other environmental challenges. Because of this, biofilms of pathogenic bacteria can be a significant health hazard often leading to recurrent infections. Biofilms can also lead to clogging and material degradation; on the other hand they are an integral part of various environmental processes such as carbon sequestration and nitrogen cycles. There are several determinants of biofilm morphology and dynamics, including the genotypic and phenotypic states of constituent cells and various environmental conditions. Here, we present an overview of the role of relevant physical processes in biofilm formation, including propulsion mechanisms, hydrodynamic effects, and transport of quorum sensing signals. We also provide a survey of microfluidic techniques utilized to unravel the associated physical mechanisms. Further, we discuss the future research areas for exploring new ways to extend the scope of the microfluidic approach in biofilm studies. PMID:25385289
NASA Astrophysics Data System (ADS)
Chernyshova, M.; Czarski, T.; Malinowski, K.; Kowalska-Strzęciwilk, E.; Poźniak, K.; Kasprowicz, G.; Zabołotny, W.; Wojeński, A.; Kolasiński, P.; Mazon, D.; Malard, P.
2015-10-01
Implementing tungsten as a plasma facing material in ITER and future fusion reactors will require effective monitoring of not just its level in the plasma but also its distribution. That can be successfully achieved using detectors based on Gas Electron Multiplier (GEM) technology. This work presents the conceptual design of the detecting unit for poloidal tomography to be tested at the WEST project tokamak. The current stage of the development is discussed covering aspects which include detector's spatial dimensions, gas mixtures, window materials and arrangements inside and outside the tokamak ports, details of detector's structure itself and details of the detecting module electronics. It is expected that the detecting unit under development, when implemented, will add to the safe operation of tokamak bringing the creation of sustainable nuclear fusion reactors a step closer. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics
Impact of ethyl pyruvate on Adriamycin-induced cardiomyopathy in rats
Liu, Menglin; Wang, Menglong; Liu, Jianfang; Luo, Zhen; Shi, Lei; Feng, Ying; Li, Li; Xu, Lin; Wan, Jun
2016-01-01
Ethyl pyruvate (EP), a derivative of pyruvic acid, is known to have protective effects against ischemic cardiomyopathy and other disorders. However, little is known about its role in Adriamycin (ADR)-induced cardiomyopathy. The present study was designed to investigate the impact of EP on ADR-induced cardiomyopathy in an animal model. Sixty male Sprague-Dawley (SD) rats were divided into four groups: Normal control, EP, ADR and ADR + EP groups (n=15/group). Rats in the ADR and ADR + EP groups were treated with ADR (2.5 mg/kg/week intraperitoneally) for 6 weeks. From the eighth week, rats in the EP and ADR + EP groups received EP via gastric lavage at a dose of 50 mg/kg/day for 30 days. After completing the EP treatment, cardiac function was assessed by echocardiography and then rats were sacrificed. Hearts were harvested for subsequent analysis. Compared with rats in the normal control and EP groups (without ADR treatment), rats in the ADR and ADR + EP groups showed significant impairments in terms of cardiac function, apoptosis, severe oxidative stress and fibrosis in the heart. However, these impairments were alleviated by EP treatment in the ADR + EP group. Upon EP treatment, cardiac function was significantly improved. The levels of oxidative stress, fibrosis and apoptosis in the myocardial tissues were also significantly reduced. These findings indicated that EP treatment attenuated, at least partially, ADR-induced cardiomyopathy in rats. PMID:27882138
Wade Taylor, S; Mayer, Kenneth H; Elsesser, Steven M; Mimiaga, Matthew J; O'Cleirigh, Conall; Safren, Steven A
2014-05-01
Existing trials of antiretroviral (ARV) medication as chemoprophylaxis against HIV reveal that the degree of protection is primarily dependent on product adherence. However, there is a lack of data on targets for behavioral interventions to improve adherence to ARV as prevention. Information from individuals who have used ARV as pre-exposure prophylaxis (PrEP) can inform behavioral intervention development. Thirty-nine HIV-uninfected MSM at high risk for HIV acquisition participated in one of four semi-structured focus groups. Two of the focus groups consisted of MSM who had been prescribed and used PrEP in the context of a clinical trial; the other two consisted of high-risk MSM who had not previously used PrEP. An in-depth, within-case/across-case content analysis resulted in six descriptive themes potentially salient for a PrEP adherence behavioral intervention: (1) motivations to use PrEP, (2) barriers to PrEP use, (3) facilitators to PrEP use, (4) sexual decision-making in the context of PrEP, (5) prospective PrEP education content, and, (6) perceived effective characteristics of PrEP delivery personnel. Addressing these themes in behavioral interventions in the context of prescribing PrEP may result in the optimal "packaging" public health programs that implement PrEP for high-risk MSM.
Pressure Sensing with Fiber Optics and Interferometry.
1980-12-01
equation yields the interference term of interest (I,2) as shown. 1 2 > = I + 12 + 1 (Eq. 2.2) where I 1 < E2 > ’ = < 2 > 12=< El EP. > t+T E Taking the...is associated with the P’ZT control loop. Laser & Supply, Spectra Physics Model 142........ ..... . ... 1 ea High Voltage DC Op-Amp, Burleigh PZ.-70...The following equipment is associated with the A/O control loop. Modified Laser Exciter, Spectra Physics Model 132 .. ...... 1 Gain Tube, Jodon cf
Cross-Calibration of GPS Proton Data with GOES EPS: A New Dataset for Space Weather Research
NASA Astrophysics Data System (ADS)
Carver, M.; Sullivan, J. P.; Morley, S.; Rodriguez, J. V.
2017-12-01
Accurate proton flux measurements of the near Earth environment are essential to the understanding of many phenomena which have a direct impact on our lives. Currently there are only small set of satellites capable of performing these measurements which makes certain studies and analyses difficult. This presentation details the capabilities of the Combined X-ray Dosimeter (CXD), flown on 21 satellites of the Global Positioning System (GPS) constellation, as it relates to proton measurements. We present a cross-calibration of the CXD with the Energetic Particle Sensor (EPS) onboard the Geostationary Operational Environmental Satellite (GOES) operated by the National Oceanic and Atmospheric Agency (NOAA). By utilizing Solar Energetic Particle events (SEPs) when both sets of satellites were operational we have orders of magnitude in flux and energy to compare against. Robust statistical analyses show that the CXD and GOES flux calculations are similar and that for proton energies > 30 MeV the CXD fluxes are on average within 20% of EPS. Although the CXD has a response to protons as low as 6 MeV the sensitivity at energies below 30 MeV are reduced and so flux comparisons of these are generally worse. Integral flux values > 10 MeV are typically within 45% of EPS. These calibrated CXD data sets will give researchers capabilities to monitor the space weather environment at unprecedented levels as well as new insights into the physics of the magnetosphere.
2018-01-01
Background Awareness of pre-exposure prophylaxis (PrEP) for HIV prevention is increasing, but little is known about the functional knowledge of PrEP and its impact on willingness to use PrEP. Objective The objective of this study was to assess the functional knowledge of PrEP among a sample of gay, bisexual, and other men who have sex with men (MSM) participating in a Web-based survey of sexually active MSM. Methods Men at least 18 years old, residing in the United States, and reporting sex with a man in the previous 6 months were recruited through social networking websites. PrEP functional knowledge included the following 4 questions (1) efficacy of consistent PrEP use, (2) inconsistent PrEP use and effectiveness, (3) PrEP and condom use, and (4) effectiveness at reducing sexually transmitted infections (STIs). Ordinal logistic regression was used to identify respondent characteristics associated with PrEP functional knowledge. In a subsample of participants responding to HIV prevention questions, we compared willingness to use PrEP by response to PrEP functional knowledge using logistic regression analysis adjusted for age, race and ethnicity, and education level. Results Among 573 respondents, PrEP knowledge was high regarding adherence (488/573, 85.2%), condom use (532/573, 92.8%), and STIs (480/573, 83.8%), but only 252/573 (44.0%) identified the correct efficacy. Lower functional PrEP knowledge was associated with minority race/ethnicity (P=.005), lower education (P=.01), and not having an HIV test in the past year (P=.02). Higher PrEP knowledge was associated with willingness to use PrEP (P=.009). Younger age was not associated with higher PrEP functional knowledge or willingness to use PrEP. Conclusions PrEP knowledge was generally high in our study, including condom use and consistent use but may be lacking in higher risk MSM. The majority of respondents did not correctly identify PrEP efficacy with consistent use, which could impact motivation to seek out PrEP for HIV prevention. Targeted messaging to increase PrEP knowledge may increase PrEP use. PMID:29362213
Inada, Takefumi; Kubo, Kozue; Shingu, Koh
2010-10-01
Propofol is an intravenous anesthetic, widely used for general anesthesia during surgery, which inevitably involves tissue trauma with inflammation. At sites of inflammation, prostanoids, especially prostaglandin E₂ (PGE₂), are abundant. This study addresses the effect of propofol on macrophage PGE₂ production. Using thioglycollate-elicited murine peritoneal macrophages, propofol (7.5-30 μM) suppressed lipopolysaccharide-induced PGE₂ production. The suppression was via the direct inhibition of cyclooxygenase (COX) enzyme activity and due neither to the downregulation of COX expression nor the inhibition of arachidonic acid release from plasma membranes. In macrophage:natural killer (NK) cell co-culture, propofol dramatically increased interferon-gamma (IFN-γ) production, and the actions of propofol were mimicked by a selective COX-2 inhibitor, NS-398, as well as the selective EP4 receptor antagonist L-161,982, suggesting a role of PGE₂ suppression in the upregulation of IFN-γ production. Furthermore, in purified NK cell culture, PGE₂ directly suppressed the production of IFN-γ by activated NK cells, which was reversed by selective inhibition of EP4 activity. Taken together, our results show that, in macrophage:NK cell co-culture, propofol, through the suppression of macrophage PGE₂ production, upregulates NK cell IFN-γ production by alleviating EP4 receptor-mediated suppression of IFN-γ production. Propofol may potentially exert considerable influence on inflammation and immunity by suppressing PGE₂ synthesis. Copyright © 2010 Elsevier B.V. All rights reserved.
Breton, Hélène; Cociglio, Marylène; Bressolle, Françoise; Peyriere, Hélène; Blayac, Jean Pierre; Hillaire-Buys, Dominique
2005-12-15
Carbamazepine (CBZ) and oxcarbazepine (OXCBZ) are both antiepileptic drugs, which are prescribed as first-line drugs for the treatment of partial and generalized tonic-clonic epileptic seizures. In this paper, a specific and sensitive liquid chromatography-electrospray ionization mass spectrometry method was described for the simultaneous determination of carbamazepine (CBZ), oxcarbazepine (OXCBZ) and eight of their metabolites [CBZ-10,11-epoxide (CBZ-EP), 10,11-dihydro-10,11-trans-dihydroxy-carbamazepine (DiOH-CBZ), 10-hydroxy-10,11-dihydroCBZ (10-OH-CBZ), 2-hydroxycarbamazepine (2-OH-CBZ), 3-hydroxycarbamazepine (3-OH-CBZ), iminostilbene (IM), acridone (AO) and acridine (AI)] in human plasma. The work-up procedure involved a simple precipitation with acetone. Separation of the analytes was achieved within 50 min using a Zorbax eclipse XD8 C8 analytical column. The mobile phase consisted of a mixture of acetonitrile-formate buffer (2 mM, pH 3). Detection was performed using a quadrupole mass spectrometer fitted with an electrospray ion source. Mass spectrometric data were acquired in single ion recording mode at m/z 237 for CBZ, m/z 180 for CBZ-EP and AI, m/z 236 for OXCBZ, m/z 237 for 10-OH-CBZ, m/z 253 for 2-OH-CBZ, 3-OH-CBZ and DiOH-CBZ, m/z 196 for AO and m/z 194 for IM. For all analytes, the drug/internal standard peak height ratios were linked via a quadratic relationship to plasma concentrations. The extraction recovery averaged 90% for CBZ, 80% for OXCBZ and was 80-105% for the metabolites. The lower limit of quantitation was 0.5mg/l for CBZ, 0.4 mg/l for OXCBZ and ranged from 0.02 to 0.3 mg/l for the metabolites. Precision ranged from 2 to 13% and accuracy was between 86 and 112%. This method was found suitable for the analysis of plasma samples collected during therapeutic drug monitoring of patients treated with CBZ or OXCBZ.
Zhao, Linting; She, Zonglian; Jin, Chunji; Yang, Shiying; Guo, Liang; Zhao, Yangguo; Gao, Mengchun
2016-09-01
The composition and distribution of extracellular polymeric substance (EPS) both from suspended sludge and attached biofilm were investigated in a simultaneous nitrification and denitrification (SND) system with the increase of the salinity from 1.0 to 3.0 %. Fourier-transform infrared (FTIR) spectroscopy and three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy were used to examine proteins (PN), polysaccharides (PS) and humic substances (HS) present in EPS. High total nitrogen removal (above 83.9 %) via SND was obtained in the salinity range of 1.0-2.5 %. Total EPS in the sludge increased from 150.2 to 200.6 mg/gVSS with the increase of salinity from 1.0 to 3.0 %, whereas the corresponding values in the biofilm achieved the maximum of 288.6 mg/g VSS at 2.0 % salinity. Dominant composition of EPS was detected as HS in both sludge and biofilm, having the percentages of 50.6-68.6 and 41.1-69.9 % in total EPS, respectively. Both PN and PS contents in soluble EPS (S-EPS), loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS) of sludge and biofilm increased with the increased salinity. The FTIR spectrum and 3D-EEM fluorescence spectroscopy of S-EPS, LB-EPS and TB-EPS in the sludge and biofilm showed the changes of functional groups and conformations of the compositions in EPS with the increase of salinity. The results demonstrated that the characteristics of EPS varied from sludge to biofilm. The obtained results could provide a better understanding of the salinity effect on the EPS characteristics in a SND system.
Young Transgender Women's Attitudes Toward HIV Pre-exposure Prophylaxis.
Wood, Sarah M; Lee, Susan; Barg, Frances K; Castillo, Marne; Dowshen, Nadia
2017-05-01
Our primary aim was to explore themes regarding attitudes toward HIV pre-exposure prophylaxis (PrEP) among young transgender women (YTW), in order to develop a theoretical model of PrEP uptake in this population disproportionally affected by HIV. Qualitative study nested within a mixed-method study characterizing barriers and facilitators to health services for YTW. Participants completed an in-depth interview exploring awareness of and attitudes toward PrEP. Key themes were identified using a grounded theory approach. Participants (n = 25) had a mean age of 21.2 years (standard deviation 2.2, range 17-24) and were predominately multiracial (36%) and of HIV-negative or unknown status (68%). Most participants (64%) reported prior knowledge of PrEP, and 28% reported current use or intent to use PrEP. Three major content themes that emerged were variability of PrEP awareness, barriers and facilitators to PrEP uptake, and emotional benefits of PrEP. Among participants without prior PrEP knowledge, participants reported frustration that PrEP information has not been widely disseminated to YTW, particularly by health care providers. Attitudes toward PrEP were overwhelmingly positive; however, concerns were raised regarding barriers including cost, stigma, and adherence challenges. Both HIV-positive and negative participants discussed emotional and relationship benefits of PrEP, which were felt to extend beyond HIV prevention alone. A high proportion of YTW in this study had prior knowledge of PrEP, and attitudes toward PrEP were positive among participants. Our findings suggest several domains to be further explored in PrEP implementation research, including methods of facilitating PrEP dissemination and emotional motivation for PrEP uptake. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Schlekat, C.E.; Decho, Alan W.; Chandler, G.T.
1999-01-01
Bacterial extracellular substances (also known as exopolysaccharides, or EPS) may serve as vectors for trophic transfer of metals in benthic systems because these ubiquitous sediment coatings can sorb high concentrations of toxic metals, and because many benthic invertebrates assimilate EPS sediment coatings upon ingestion. We conducted 3 sets of experiments to determine the assimilative bioavailability of EPS-associated Cd to the benthic amphipod Leptocheirus plumulosus as a function of Cd concentration and salinity. Bioavailability was measured as L. plumulosus Cd assimilation efficiency (AE) from EPS-coated silica (EPS-Si) and from uncoated silica (NC-Si) using modified pulse-chase methods with the gamma-emitting radioisotope 109Cd. Cd AE was significantly greater from NC-Si than from EPS-Si at 7.5???, but not at 2.5 or 25???. Overall, Cd AE from EPS-Si was between 15.1 and 21.5%. Because EPS-Si sorbed more Cd than NC-Si, EPS coatings magnified the amount of Cd amphipods accumulated at each salinity by up to a factor of 10. Salinity did not directly affect Cd AE from EPS-Si, but because Cd-EPS partitioning increased with decreasing salinity, amphipods accumulated more Cd from EPS at the lowest Cd-EPS incubation salinity (2.5 ???) than at higher salinities (7.5 and 25 ???). Finally, Cd concentration in EPS exhibited an inverse relationship with Cd AE at 2.5 ???, but not at 25 ???. Specifically, Cd AE was 12 times greater at 1 compared with 10 ??g Cd ??g-1 EPS. Together, these results show that estuarine benthos can accumulate Cd from EPS sediment coatings, but that the degree to which this phenomenon occurs is dependent upon seawater salinity and Cd concentration in EPS.
PrEP awareness and decision-making for Latino MSM in San Antonio, Texas
García, Moctezuma; Harris, Allyssa L.
2017-01-01
Pre-Exposure Prophylaxis (PrEP) has been promoted among high-risk populations as an effective HIV biomedical intervention. However, limited research is available on the significance of culturally informed biomedical interventions for Latino MSM. A total of 159 self-administered Internet surveys were completed by Latino MSM ages 21–30 in San Antonio, Texas. The purpose of this research was to develop an instrument that measured Latino MSM attitudes and beliefs towards PrEP, identify associations between demographic factors and PrEP related factors and to suggest culturally appropriate strategies for the promotion of PrEP among the Latino MSM population. Research findings revealed implications for PrEP at the structural and individual level for Latino MSM. Structural level indicators emphasized the importance for raising PrEP awareness among Latino MSM in regards to PrEP related expenses, ameliorating stigmatization of high-risk populations, enhancing access to PrEP informed medical providers, and address mistrust of the government and medical providers role on addressing health disparities among Latino MSM. Overall, the findings for individual factors emphasize the need for patient-centered interventions for Latino MSM. Latino MSM currently on PrEP require supplemental resources to enhance PrEP adherence. Latino MSM not on PrEP require alternate options for PrEP delivery and/or cognitive behavioral approaches minimizing HIV risk behavior for Latino MSM concerned with PrEP toxicity, which may require non-biomedical interventions. Integration of Latino MSM currently on PrEP as peer educators provides a valuable resource for developing culturally informed PrEP interventions for Latino MSM. Peer educators are able to share their experiential knowledge of PrEP contextualized through cultural norms, beliefs, and values. PMID:28953905
EpCAM and the biology of hepatic stem/progenitor cells
Theise, Neil D.; Schmelzer, Eva; Boulter, Luke; Gires, Olivier; van Grunsven, Leo A.
2014-01-01
Epithelial cell adhesion molecule (EpCAM) is a transmembrane glycoprotein, which is frequently and highly expressed on carcinomas, tumor-initiating cells, selected tissue progenitors, and embryonic and adult stem cells. During liver development, EpCAM demonstrates a dynamic expression, since it can be detected in fetal liver, including cells of the parenchyma, whereas mature hepatocytes are devoid of EpCAM. Liver regeneration is associated with a population of EpCAM-positive cells within ductular reactions, which gradually lose the expression of EpCAM along with maturation into hepatocytes. EpCAM can be switched on and off through a wide panel of strategies to fine-tune EpCAM-dependent functional and differentiative traits. EpCAM-associated functions relate to cell–cell adhesion, proliferation, maintenance of a pluripotent state, regulation of differentiation, migration, and invasion. These functions can be conferred by the full-length protein and/or EpCAM-derived fragments, which are generated upon regulated intramembrane proteolysis. Control by EpCAM therefore not only depends on the presence of full-length EpCAM at cellular membranes but also on varying rates of the formation of EpCAM-derived fragments that have their own regulatory properties and on changes in the association of EpCAM with interaction partners. Thus spatiotemporal localization of EpCAM in immature liver progenitors, transit-amplifying cells, and mature liver cells will decisively impact the regulation of EpCAM functions and might be one of the triggers that contributes to the adaptive processes in stem/progenitor cell lineages. This review will summarize EpCAM-related molecular events and how they relate to hepatobiliary differentiation and regeneration. PMID:25477371
A Michelson Interferometer for Electron Cyclotron Emission Measurements on EAST
NASA Astrophysics Data System (ADS)
Liu, Yong; Stefan, Schmuck; Zhao, Hailin; John, Fessey; Paul, Trimble; Liu, Xiang; Zhu, Zeying; Zang, Qing; Hu, Liqun
2016-12-01
A Michelson interferometer, on loan from EFDA-JET (Culham, United Kingdom) has recently been commissioned on the experimental advanced superconducting tokamak (EAST, ASIPP, Hefei, China). Following a successful in-situ absolute calibration the instrument is able to measure the electron cyclotron emission (ECE) spectrum, from 80 GHz to 350 GHz in extraordinary mode (X-mode) polarization, with high accuracy. This allows the independent determination of the electron temperature profile from observation of the second harmonic ECE and the possible identification of non-Maxwellian features by comparing higher harmonic emission with numerical simulations. The in-situ calibration results are presented together with the initial measured temperature profiles. These measurements are then discussed and compared with other independent temperature profile measurements. This paper also describes the main hardware features of the diagnostic and the associated commissioning test results. supported by National Natural Science Foundation of China (Nos. 11405211, 11275233), and the National Magnetic Confinement Fusion Science Program of China (Nos. 2013GB106002, 2015GB101000), and the RCUK Energy Programme (No. EP/I501045), partly supported by the JSPS-NRF-NSFC A3 Foresight Program in the Field of Plasma Physics (NSFC: No. 11261140328)
Physics through the 1990s: Plasmas and fluids
NASA Technical Reports Server (NTRS)
1986-01-01
The volume contains recommendations for programs in, and government support of, plasma and fluid physics. Four broad areas are covered: the physics of fluids, general plasma physics, fusion, and space and astrophysical plasmas. In the first section, the accomplishments of fluid physics and a detailed review of its sub-fields, such as combustion, non-Newtonian fluids, turbulence, aerodynamics, and geophysical fluid dynamics, are described. The general plasma physics section deals with the wide scope of the theoretical concepts involved in plasma research, and with the machines; intense beam systems, collective and laser-driven accelerators, and the associated diagnostics. The section on the fusion plasma research program examines confinement and heating systems, such as Tokamaks, magnetic mirrors, and inertial-confinement systems, and several others. Finally, theory and experiment in space and astrophysical plasma research is detailed, ranging from the laboratory to the solar system and beyond. A glossary is included.
Bil, Janneke P; van der Veldt, Wendy M; Prins, Maria; Stolte, Ineke G; Davidovich, Udi
2016-09-01
Although PrEP is not yet registered in Europe, including the Netherlands, its approval and implementation are expected in the near future. To inform future pre-exposure prophylaxis (PrEP) implementation, this study aimed to gain insight into motives and preferences for daily or intermittent PrEP use among Dutch HIV-negative men having sex with men (MSM).Between February and December 2013, semistructured interviews were conducted until data saturation was reached (N = 20). Interviews were analyzed using the Grounded Theory approach.Motives for (not) using daily PrEP were based on beliefs about PrEP efficacy and side effects, preferences for other prevention strategies, self-perceived HIV risk, self-perceived efficacy of PrEP adherence, beliefs about possible benefits (e.g., anxiety reduction, sex life improvement), and barriers of PrEP use (e.g., costs, monitoring procedures). The perceived benefits of intermittent versus daily PrEP use were the lower costs and side effects and the lower threshold to decision to start using intermittent PrEP. Barriers of intermittent PrEP versus daily PrEP use were the perceived need to plan their sex life and adhere to multiple prevention strategies. Although some perceived PrEP as a condom substitute, others were likely to combine PrEP and condoms for sexually transmitted infections (STI) prevention and increased HIV protection. Participants preferred PrEP service locations to have specialized knowledge of HIV, antiretroviral therapy, sexual behavior, STIs, patients' medical background, be easily approachable, be able to perform PrEP follow-up monitoring, and provide support.To maximize the public health impact of PrEP, ensuring high uptake among MSM at highest risk is important. Therefore, targeted information about PrEP efficacy and side effects need to be developed, barriers for accessing PrEP services should be minimized, and perceived self-efficacy to use PrEP should be addressed and improved. To prevent increases in STIs, condom use should be monitored and PrEP should be integrated into routine STI screening and counseling.
Bil, Janneke P.; van der Veldt, Wendy M.; Prins, Maria; Stolte, Ineke G.; Davidovich, Udi
2016-01-01
Abstract Although PrEP is not yet registered in Europe, including the Netherlands, its approval and implementation are expected in the near future. To inform future pre-exposure prophylaxis (PrEP) implementation, this study aimed to gain insight into motives and preferences for daily or intermittent PrEP use among Dutch HIV-negative men having sex with men (MSM). Between February and December 2013, semistructured interviews were conducted until data saturation was reached (N = 20). Interviews were analyzed using the Grounded Theory approach. Motives for (not) using daily PrEP were based on beliefs about PrEP efficacy and side effects, preferences for other prevention strategies, self-perceived HIV risk, self-perceived efficacy of PrEP adherence, beliefs about possible benefits (e.g., anxiety reduction, sex life improvement), and barriers of PrEP use (e.g., costs, monitoring procedures). The perceived benefits of intermittent versus daily PrEP use were the lower costs and side effects and the lower threshold to decision to start using intermittent PrEP. Barriers of intermittent PrEP versus daily PrEP use were the perceived need to plan their sex life and adhere to multiple prevention strategies. Although some perceived PrEP as a condom substitute, others were likely to combine PrEP and condoms for sexually transmitted infections (STI) prevention and increased HIV protection. Participants preferred PrEP service locations to have specialized knowledge of HIV, antiretroviral therapy, sexual behavior, STIs, patients’ medical background, be easily approachable, be able to perform PrEP follow-up monitoring, and provide support. To maximize the public health impact of PrEP, ensuring high uptake among MSM at highest risk is important. Therefore, targeted information about PrEP efficacy and side effects need to be developed, barriers for accessing PrEP services should be minimized, and perceived self-efficacy to use PrEP should be addressed and improved. To prevent increases in STIs, condom use should be monitored and PrEP should be integrated into routine STI screening and counseling. PMID:27684827
Demographic Differences in PrEP-Related Stereotypes: Implications for Implementation.
Golub, Sarit A; Gamarel, Kristi E; Surace, Anthony
2017-05-01
Qualitative interviews about pre-exposure prophylaxis (PrEP) stereotypes were conducted with a subsample of 160 MSM who participated in a PrEP messaging study. Negative stereotypes about PrEP users were identified by 80 % of participants. Two types of stereotypes were most common: PrEP users are HIV-infected (and lying about it), and PrEP users are promiscuous and resistant to condom use. Participants' identification of these stereotype categories differed significantly by demographic factors (i.e., race/ethnicity, education). Expanding access to PrEP requires recognizing potential differences in the experience or anticipation of PrEP-related stereotypes that might impact willingness to discuss PrEP with providers, friends, or partners.
Fungal Exopolysaccharide: Production, Composition and Applications
Mahapatra, Subhadip; Banerjee, Debdulal
2013-01-01
Fungal exopolysaccharides (EPSs) have been recognized as high value biomacromolecules for the last two decades. These products, including pullulan, scleroglucan, and botryosphaeran, have several applications in industries, pharmaceuticals, medicine, foods etc. Although fungal EPSs are highly relevant, to date information concerning fungal biosynthesis is scarce and an extensive search for new fugal species that can produce novel EPSs is still needed. In most cases, the molecular weight variations and sugar compositions of fungal EPSs are dependent to culture medium composition and different physical conditions provided during fermentation. An inclusive and illustrative review on fungal EPS is presented here. The general outline of the present work includes fungal EPS production, their compositions and applications. An emphasis is also given to listing out different fungal strains that can produce EPSs. PMID:24826070
Xiao, Keke; Chen, Yun; Jiang, Xie; Zhou, Yan
2017-03-01
An investigation was conducted for 20 different types of sludge in order to identify the key organic compounds in extracellular polymeric substances (EPS) that are important in assessing variations of sludge filterability. The different types of sludge varied in initial total solids (TS) content, organic composition and pre-treatment methods. For instance, some of the sludges were pre-treated by acid, ultrasonic, thermal, alkaline, or advanced oxidation technique. The Pearson's correlation results showed significant correlations between sludge filterability and zeta potential, pH, dissolved organic carbon, protein and polysaccharide in soluble EPS (SB EPS), loosely bound EPS (LB EPS) and tightly bound EPS (TB EPS). The principal component analysis (PCA) method was used to further explore correlations between variables and similarities among EPS fractions of different types of sludge. Two principal components were extracted: principal component 1 accounted for 59.24% of total EPS variations, while principal component 2 accounted for 25.46% of total EPS variations. Dissolved organic carbon, protein and polysaccharide in LB EPS showed higher eigenvector projection values than the corresponding compounds in SB EPS and TB EPS in principal component 1. Further characterization of fractionized key organic compounds in LB EPS was conducted with size-exclusion chromatography-organic carbon detection-organic nitrogen detection (LC-OCD-OND). A numerical multiple linear regression model was established to describe relationship between organic compounds in LB EPS and sludge filterability. Copyright © 2016 Elsevier Ltd. All rights reserved.
Wang, Zichao; Gao, Mengchun; Xin, Yanjun; Ma, Dong; She, Zonglian; Wang, Zhe; Sun, Changqing; Ren, Yun
2014-01-01
The effect of C/N ratio on extracellular polymeric substances (EPS) of activated sludge was investigated in an anoxic-aerobic sequencing batch reactor (SBR) treating saline wastewater. The protein (PN) and protein/polysaccharide (PN/PS) ratio in the loosely bound EPS (LB-EPS) increased with the decrease of C/N ratio, whereas the PS in the LB-EPS decreased. The PS, PN and PN/PS ratio in the tightly bound EPS (TB-EPS) were independent of C/N ratio. Two fluorescence peaks in the LB-EPS and TB-EPS were identified at excitation/emission (Ex/Em) wavelengths of 275-280/335-340 nm and 220-225/330-340 nm by three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy, respectively. These peaks in LB-EPS and TB-EPS were, respectively, associated with tryptophan protein-like substances and aromatic protein-like substances. The tryptophan protein-like fluorescence peaks in LB-EPS showed blue shift along the Ex axis and red shift along the Em axis with the decrease of C/N ratio. Fourier transform infrared spectra suggested that the variation of C/N ratio had more distinct effect on the functional groups of protein in the LB-EPS than those in the TB-EPS. The sludge volume index value decreased with the increase of LB-EPS, but there was no correlation between SVI and TB-EPS.
PrEP implementation in the Asia-Pacific region: opportunities, implementation and barriers
Zablotska, Iryna; Grulich, Andrew E; Phanuphak, Nittaya; Anand, Tarandeep; Janyam, Surang; Poonkasetwattana, Midnight; Baggaley, Rachel; van Griensven, Frits; Lo, Ying-Ru
2016-01-01
Introduction HIV epidemics in the Asia-Pacific region are concentrated among men who have sex with men (MSM) and other key populations. Pre-exposure prophylaxis (PrEP) is an effective HIV prevention intervention and could be a potential game changer in the region. We discuss the progress towards PrEP implementation in the Asia-Pacific region, including opportunities and barriers. Discussion Awareness about PrEP in the Asia-Pacific is still low and so are its levels of use. A high proportion of MSM who are aware of PrEP are willing to use it. Key PrEP implementation barriers include poor knowledge about PrEP, limited access to PrEP, weak or non-existent HIV prevention programmes for MSM and other key populations, high cost of PrEP, stigma and discrimination against key populations and restrictive laws in some countries. Only several clinical trials, demonstration projects and a few larger-scale implementation studies have been implemented so far in Thailand and Australia. However, novel approaches to PrEP implementation have emerged: researcher-, facility- and community-led models of care, with PrEP services for fee and for free. The WHO consolidated guidelines on HIV testing, treatment and prevention call for an expanded access to PrEP worldwide and have provided guidance on PrEP implementation in the region. Some countries like Australia have released national PrEP guidelines. There are growing community leadership and consultation processes to initiate PrEP implementation in Asia and the Pacific. Conclusions Countries of the Asia-Pacific region will benefit from adding PrEP to their HIV prevention packages, but for many this is a critical step that requires resourcing. Having an impact on the HIV epidemic requires investment. The next years should see the region transitioning from limited PrEP implementation projects to growing access to PrEP and expansion of HIV prevention programmes. PMID:27760688
Enhancing HIV Pre-exposure, Prophylaxis Practices via an Educational Intervention.
Newman, Rebecca; Katchi, Tasleem; Karass, Michael; Gennarelli, Melissa; Goutis, Jason; Kifayat, Alina; Solanki, Shantanu; Yandrapalli, Srikanth; Forman, Leanne; Nabors, Christopher
2018-04-20
Pre-exposure prophylaxis (PrEP) for HIV involves using antiretroviral drugs to prevent individuals at high risk from acquiring HIV infection. Most practicing primary care providers believe PrEP to be safe and effective, but less than half have prescribed or referred for PrEP. Attitudes and prescribing patterns among house officers have not been well described previously. Can an educational intervention enhance HIV PrEP practices among internal medicine house officers? This study relied on a pretest/posttest design. All categorical trainees at a medium-sized internal medicine program were offered a baseline survey to assess their knowledge on PrEP. This was followed by a PrEP-focused educational intervention and a postintervention survey. Likert scales captured perceptions regarding safety, effectiveness, barriers, factors that would promote PrEP use, potential side effects, impact on risk-taking behavior, and provider comfort level in assessing behavioral risks and in PrEP prescribing. Data were analyzed using descriptive statistics, Wilcoxon signed rank test, and the Kruskal-Wallis test. Significance was accepted for P < 0.05. Forty-eight (100%) trainees participated in the educational session, 45 (94%) in a preintervention survey, and 36 (75%) in a postintervention survey. Before PrEP training, 22% of respondents were unaware of PrEP, 78% believed PrEP was effective, 66% believed PrEP was safe, 62% had fair or poor awareness of side effects; 18% of residents had referred for or prescribed PrEP, and 31% believed they were likely to prescribe PrEP in the next 6 months. After the intervention, 94% of trainees believed PrEP was effective (P < 0.001), 92% believed PrEP was safe (P < 0.001), and two-thirds believed they were likely to prescribe PrEP in the next 6 months. Brief, focused training on HIV prevention promotes awareness, acceptance, and likelihood of prescribing PrEP by internal medicine trainees.
PrEP implementation in the Asia-Pacific region: opportunities, implementation and barriers.
Zablotska, Iryna; Grulich, Andrew E; Phanuphak, Nittaya; Anand, Tarandeep; Janyam, Surang; Poonkasetwattana, Midnight; Baggaley, Rachel; van Griensven, Frits; Lo, Ying-Ru
2016-01-01
HIV epidemics in the Asia-Pacific region are concentrated among men who have sex with men (MSM) and other key populations. Pre-exposure prophylaxis (PrEP) is an effective HIV prevention intervention and could be a potential game changer in the region. We discuss the progress towards PrEP implementation in the Asia-Pacific region, including opportunities and barriers. Awareness about PrEP in the Asia-Pacific is still low and so are its levels of use. A high proportion of MSM who are aware of PrEP are willing to use it. Key PrEP implementation barriers include poor knowledge about PrEP, limited access to PrEP, weak or non-existent HIV prevention programmes for MSM and other key populations, high cost of PrEP, stigma and discrimination against key populations and restrictive laws in some countries. Only several clinical trials, demonstration projects and a few larger-scale implementation studies have been implemented so far in Thailand and Australia. However, novel approaches to PrEP implementation have emerged: researcher-, facility- and community-led models of care, with PrEP services for fee and for free. The WHO consolidated guidelines on HIV testing, treatment and prevention call for an expanded access to PrEP worldwide and have provided guidance on PrEP implementation in the region. Some countries like Australia have released national PrEP guidelines. There are growing community leadership and consultation processes to initiate PrEP implementation in Asia and the Pacific. Countries of the Asia-Pacific region will benefit from adding PrEP to their HIV prevention packages, but for many this is a critical step that requires resourcing. Having an impact on the HIV epidemic requires investment. The next years should see the region transitioning from limited PrEP implementation projects to growing access to PrEP and expansion of HIV prevention programmes.
Rendina, H Jonathon; Whitfield, Thomas H F; Grov, Christian; Starks, Tyrel J; Parsons, Jeffrey T
2017-01-01
Much of the data on the acceptability of HIV Pre-Exposure Prophylaxis (PrEP) is based on willingness to take PrEP (i.e., hypothetical receptivity) rather than actual intentions (i.e., planned behavioral action) to do so. We sought to examine differences between hypothetical willingness and behavioral intentions to begin PrEP in a national sample of gay and bisexual men (GBM) across the U.S. We utilized data collected in 2015 to examine differences between those Unwilling (42.6% n = 375), Willing but not intending (41.4%, n = 365), and willing and Intending to take PrEP (15.9%, n = 140) in a multivariable, multinomial logistic regression. Men with less education had higher odds of Intending to take PrEP. Compared to men unsure about PrEP's efficacy, those who believed PrEP was at least 90% efficacious had higher odds of Intending to take PrEP. Those who saw themselves as appropriate candidates for PrEP had higher odds of Intending to take PrEP while those who saw themselves as inappropriate candidates for PrEP had lower odds of Intending to take PrEP in comparison to men unsure if they were appropriate candidates. Increased motivation for condom non-use because of perceived sexual pressure by partners was associated with higher odds of Intending to take PrEP. The groups did not differ by risk behavior nor recent STI diagnosis. Overall, the distinction between willingness and intentions to take PrEP was meaningful and may help explain disparities between PrEP acceptability and uptake. While much of the literature has focused on hypothetical willingness to take PrEP, these results highlight the importance of simultaneously assessing willingness and intentions when examining correspondence with uptake and developing interventions to increase PrEP uptake. Copyright © 2016 Elsevier Ltd. All rights reserved.
Space Station Freedom electric power system availability study
NASA Technical Reports Server (NTRS)
Turnquist, Scott R.
1990-01-01
The results are detailed of follow-on availability analyses performed on the Space Station Freedom electric power system (EPS). The scope includes analyses of several EPS design variations, these are: the 4-photovoltaic (PV) module baseline EPS design, a 6-PV module EPS design, and a 3-solar dynamic module EPS design which included a 10 kW PV module. The analyses performed included: determining the discrete power levels that the EPS will operate at upon various component failures and the availability of each of these operating states; ranking EPS components by the relative contribution each component type gives to the power availability of the EPS; determining the availability impacts of including structural and long-life EPS components in the availability models used in the analyses; determining optimum sparing strategies, for storing space EPS components on-orbit, to maintain high average-power-capability with low lift-mass requirements; and analyses to determine the sensitivity of EPS-availability to uncertainties in the component reliability and maintainability data used.
Incorporation of bacterial extracellular polysaccharide by black fly larvae (Simuliidae)
Couch, C.A.; Meyer, J.L.; Hall, R.O.
1996-01-01
Black fly larvae (Simulium) assimilated, with high efficiency (80-90%), bacterial extracellular polysaccharide (EPS) extracted from laboratory cultures of a pseudomonad isolated from the Ogeechee River. Incorporation was traced using 13C-labelled EPS offered to larvae as a coating on a mixture of 1-??m latex beads and kaolin particles. These EPS-coated particles were used to simulate natural particles, both living and dead. Solubility, protein, and nitrogen content of the EPS suggested it was a slime rather than a capsular polysaccharide. Glycosyl composition of the EPS was glucose and galactose in ?? and ?? linkages, with pyruvate, succinate, and possibly malonate constituent groups. To evaluate the incorporation of C derived from protein associated with the EPS matrix, feeding experiments were conducted using EPS with and without proteins extracted. Black fly larvae incorporated 7.2 ??g EPS C larva-1 d-1 from EPS that did not have proteins extracted, and 19.5 ??g EPS C larva-1 d-1 from EPS with proteins extracted. Carbon in protein that is typically associated with EPS was not solely or selectively incorporated. EPS incorporation rates are similar to rates of cellular bacterial carbon incorporation previously estimated for Ogeechee River black fly larvae. If EPS is generally available as a food resource, the importance of bacteria in detrital food webs may be underestimated by studies that examine only the consumption of bacterial cells.
Cao, Bin; Ahmed, Bulbul; Kennedy, David W; Wang, Zheming; Shi, Liang; Marshall, Matthew J; Fredrickson, Jim K; Isern, Nancy G; Majors, Paul D; Beyenal, Haluk
2011-07-01
The goal of this study was to quantify the contribution of extracellular polymeric substances (EPS) to U(VI) immobilization by Shewanella sp. HRCR-1. Through comparison of U(VI) immobilization using cells with bound EPS (bEPS) and cells with minimal EPS, we show that (i) bEPS from Shewanella sp. HRCR-1 biofilms contribute significantly to U(VI) immobilization, especially at low initial U(VI) concentrations, through both sorption and reduction; (ii) bEPS can be considered a functional extension of the cells for U(VI) immobilization and they likely play more important roles at lower initial U(VI) concentrations; and (iii) the U(VI) reduction efficiency is dependent upon the initial U(VI) concentration and decreases at lower concentrations. To quantify the relative contributions of sorption and reduction to U(VI) immobilization by EPS fractions, we isolated loosely associated EPS (laEPS) and bEPS from Shewanella sp. HRCR-1 biofilms grown in a hollow fiber membrane biofilm reactor and tested their reactivity with U(VI). We found that, when reduced, the isolated cell-free EPS fractions could reduce U(VI). Polysaccharides in the EPS likely contributed to U(VI) sorption and dominated the reactivity of laEPS, while redox active components (e.g., outer membrane c-type cytochromes), especially in bEPS, possibly facilitated U(VI) reduction.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cao, Bin; Ahmed, B.; Kennedy, David W.
2011-06-05
The goal of this study was to quantify the contribution of extracellular polymeric substances (EPS) in U(VI) immobilization by Shewanella sp. HRCR-1. Through comparison of U(VI) immobilization using cells with bound EPS (bEPS) and cells without EPS, we showed that i) bEPS from Shewanella sp. HRCR-1 biofilms contributed significantly to U(VI) immobilization, especially at low initial U(VI) concentrations, through both sorption and reduction; ii) bEPS could be considered as a functional extension of the cells for U(VI) immobilization and they likely play more important roles at initial U(VI) concentrations; and iii) U(VI) reduction efficiency was found to be dependent uponmore » initial U(VI) concentration and the efficiency decreased at lower concentrations. To quantify relative contribution of sorption and reduction in U(VI) immobilization by EPS fractions, we isolated loosely associated EPS (laEPS) and bEPS from Shewanella sp. HRCR-1 biofilms grown in a hollow fiber membrane biofilm reactor and tested their reactivity with U(V). We found that, when in reduced form, the isolated cell-free EPS fractions could reduce U(VI). Polysaccharides in the EPS likely contributed to U(VI) sorption and dominated reactivity of laEPS while redox active components (e.g., outer membrane c-type cytochromes), especially in bEPS, might facilitate U(VI) reduction.« less
NASA Astrophysics Data System (ADS)
Liang, J.; Sofko, G.; Donovan, E.; Greenwald, R.
2002-12-01
Multi-instrument observations of a small postmidnight substorm event during a period of IMF dominated by Bz+ and By+ conditions on October 9, 2000, showed the substorm structure with high time resolution. Three optical intensifications and Pi2 bursts occurred. The last and strongest Pi2 burst was associated with an expansive phase (EP) onset, characterized by a 100 nT magnetic bay at Fort Churchill and an auroral breakup in which the 630 nm emissions moved poleward about 2.5 degrees. About 11 minutes after the first EP onset, a second stage of auroral brightening occurred. For each of the three initial optical intensifications, there was an eastward-moving discrete azimuthal structure. SuperDARN HF radar line-of-sight velocity measurements revealed eastward electric fields within each Pi2 wave train. The observations are interpreted as resulting from the drift-Alfven-ballooning (DAB) mode instability at near-geosynchronous orbit (NGO) locations. Within the NGO drift waves, regions of charge separation led to electric fields and field-aligned currents (FACs) of alternating direction. The ionospheric reflection of Alfven wave energy likely generated the Pi2 pulsations observed on the ground. The multi-instrument ground observations agree quite well with the substorm onset scenario based upon CRRES satellite observations by Erickson et al. [2000]. There was a single, relatively confined (~4 hour in MLT) counterclockwise convection cell during the growth phase and EP onset. A clearly defined vortex at its center defined the center of the downward FAC. This vortex, initially northward of the optical aurora, moved eastward and then suddenly southward just prior to the EP onset. At that time, the FAC structure was typical of the substorm current wedge (SCW). Reasons for the convection cell motion and SCW development are discussed. Erickson, G. M., N. C. Maynard, W. J. Burke, G. R. Wilson, and M. A. Heinemann, Electromagnetics of substorm onsets in the near-geosynchronous plasma sheet, J. Geophys. Res., 105, 25265, 2000.
Newcomb, Michael E; Moran, Kevin; Feinstein, Brian A; Forscher, Emily; Mustanski, Brian
2018-04-01
Young men who have sex with men (YMSM) are disproportionately impacted by HIV. Pre-exposure prophylaxis (PrEP) is highly effective at preventing HIV acquisition. It remains unclear if PrEP use increases rates of condomless sex (ie, risk compensation), which may increase risk of infection if PrEP adherence is not optimal. This study aimed to examine whether PrEP use and PrEP adherence were associated with change in sexual risk behaviors in a large longitudinal cohort of YMSM reporting on multiple sexual partnerships over time. Data were obtained from the first 3 visits of an ongoing cohort study of YMSM in Chicago (analytic N = 953; 14.1% HIV-positive at baseline). Participants reported up to 4 sexual partnerships at each visit, including sexual behavior, PrEP use, and PrEP adherence within partnerships. YMSM reported higher rates of receptive condomless anal sex (CAS) in partnerships during which they were on PrEP compared with those when they were not on PrEP. This association was consistent across both HIV-negative and HIV-positive participants reporting on partnerships with both perceived HIV-negative/unknown and HIV-positive partners. The rate of receptive CAS was higher in PrEP nonadherent partnerships compared with non-PrEP partnerships. The rate of receptive CAS was also higher in PrEP nonadherent than adherent partnerships, but this was not statistically significant. These analyses provide compelling data suggesting that YMSM are engaging in risk compensation when on PrEP. If rates of receptive CAS are highest among YMSM who are PrEP nonadherent, PrEP as a prevention strategy could fail to curb HIV incidence among YMSM.
Abnormal placental development and early embryonic lethality in EpCAM-null mice.
Nagao, Keisuke; Zhu, Jianjian; Heneghan, Mallorie B; Hanson, Jeffrey C; Morasso, Maria I; Tessarollo, Lino; Mackem, Susan; Udey, Mark C
2009-12-31
EpCAM (CD326) is encoded by the tacstd1 gene and expressed by a variety of normal and malignant epithelial cells and some leukocytes. Results of previous in vitro experiments suggested that EpCAM is an intercellular adhesion molecule. EpCAM has been extensively studied as a potential tumor marker and immunotherapy target, and more recent studies suggest that EpCAM expression may be characteristic of cancer stem cells. To gain insights into EpCAM function in vivo, we generated EpCAM -/- mice utilizing an embryonic stem cell line with a tacstd1 allele that had been disrupted. Gene trapping resulted in a protein comprised of the N-terminus of EpCAM encoded by 2 exons of the tacstd1 gene fused in frame to betageo. EpCAM +/- mice were viable and fertile and exhibited no obvious abnormalities. Examination of EpCAM +/- embryos revealed that betageo was expressed in several epithelial structures including developing ears (otocysts), eyes, branchial arches, gut, apical ectodermal ridges, lungs, pancreas, hair follicles and others. All EpCAM -/- mice died in utero by E12.5, and were small, developmentally delayed, and displayed prominent placental abnormalities. In developing placentas, EpCAM was expressed throughout the labyrinthine layer and by spongiotrophoblasts as well. Placentas of EpCAM -/- embryos were compact, with thin labyrinthine layers lacking prominent vascularity. Parietal trophoblast giant cells were also dramatically reduced in EpCAM -/- placentas. EpCAM was required for differentiation or survival of parietal trophoblast giant cells, normal development of the placental labyrinth and establishment of a competent maternal-fetal circulation. The findings in EpCAM-reporter mice suggest involvement of this molecule in development of vital organs including the gut, kidneys, pancreas, lungs, eyes, and limbs.
The anti-inflammatory effects of PGE2 on human lung macrophages are mediated by the EP4 receptor.
Gill, Sharonjit K; Yao, Yiwen; Kay, Linda J; Bewley, Martin A; Marriott, Helen M; Peachell, Peter T
2016-11-01
PGE 2 inhibits cytokine generation from human lung macrophages. However, the EP receptor that mediates this beneficial anti-inflammatory effect of PGE 2 has not been defined. The aim of this study was to identify the EP receptor by which PGE 2 inhibits cytokine generation from human lung macrophages. This was determined by using recently developed EP receptor ligands. The effects of PGE 2 and EP-selective agonists on LPS-induced generation of TNF-α and IL-6 from macrophages were evaluated. The effects of EP 2 -selective (PF-04852946, PF-04418948) and EP 4 -selective (L-161,982, CJ-042794) receptor antagonists on PGE 2 responses were studied. The expression of EP receptor subtypes by human lung macrophages was determined by RT-PCR. PGE 2 inhibited LPS-induced and Streptococcus pneumoniae-induced cytokine generation from human lung macrophages. Analysis of mRNA levels indicated that macrophages expressed EP 2 and EP 4 receptors. L-902,688 (EP 4 receptor-selective agonist) was considerably more potent than butaprost (EP 2 receptor-selective agonist) as an inhibitor of TNF-α generation from macrophages. EP 2 receptor-selective antagonists had marginal effects on the PGE 2 inhibition of TNF-α generation, whereas EP 4 receptor-selective antagonists caused rightward shifts in the PGE 2 concentration-response curves. These studies demonstrate that the EP 4 receptor is the principal receptor that mediates the anti-inflammatory effects of PGE 2 on human lung macrophages. This suggests that EP 4 receptor agonists could be effective anti-inflammatory agents in human lung disease. © 2016 The British Pharmacological Society.
Silapaswan, Andrew; Krakower, Douglas; Mayer, Kenneth H
2017-02-01
Since FDA approval of HIV pre-exposure prophylaxis (PrEP) for HIV prevention, attention has been focused on PrEP implementation. The CDC estimates that 1.2 million U.S. adults might benefit from PrEP, but only a minority are using PrEP, so there is a significant unmet need to increase access for those at risk for HIV. Given the large numbers of individuals who have indications for PrEP, there are not enough practicing specialists to meet the growing need for providers trained in providing PrEP. Moreover, since PrEP is a preventive intervention for otherwise healthy individuals, primary care providers (PCPs) should be primary prescribers of PrEP. There are important clinical considerations that providers should take into account when planning to prescribe PrEP, which are highlighted in the clinical case discussed. A growing body of research also suggests that some providers may be cautious about prescribing PrEP because of concerns regarding its "real-world" effectiveness, anticipated unintended consequences associated with its use, and ambiguity as to who should prescribe it. This review summarizes findings from studies that have assessed prescriber behavior regarding provision of PrEP, and offers recommendations on how to optimize PrEP implementation in primary care settings. Development and dissemination of educational interventions for PCPs and potential PrEP users are needed, including improved methods to assist clinicians in identifying appropriate PrEP candidates, and programs to promote medication adherence and access to social and behavioral health services. PCPs are well-positioned to prescribe PrEP and coordinate health-related services to improve the sexual health of their patients, but tailored educational programs are needed.
Fairbrother, S E; Smith, J E; Borman, R A; Cox, H M
2011-08-01
Prostaglandin E(2) (PGE(2) ) is an inflammatory mediator implicated in several gastrointestinal pathologies that affect normal intestinal transit. The aim was to establish the contribution of the four EP receptor types (EP(1-4) ), in human colon, that mediate PGE(2) -induced longitudinal smooth muscle contraction. Changes in isometric muscle tension of human colon, mouse colon and mouse ileum were measured in organ baths in response to receptor-specific agonists and antagonists. In addition, lidocaine was used to block neurogenic activity to investigate whether EP receptors were pre- or post-junctional. PGE(2) contracted longitudinal muscle from human and mouse colon and mouse ileum. These contractions were inhibited by the EP(1) receptor antagonist, EP(1) A in human colon, whereas a combination of EP(1) A and the EP(3) antagonist, L798106 inhibited agonist responses in both mouse preparations. The EP(3) agonist, sulprostone also increased muscle tension in both mouse tissues, and these responses were inhibited by lidocaine in the colon but not in the ileum. Although PGE(2) consistently contracted all three muscle preparations, butaprost decreased tension by activating smooth muscle EP(2) receptors in both colonic tissues. Alternatively, in mouse ileum, butaprost responses were lidocaine-sensitive, suggesting that it was activating prejunctional EP(2) receptors on inhibitory motor neurons. Conversely, EP(4) receptors were not functional in all the intestinal muscle preparations tested. PGE(2) -induced contraction of longitudinal smooth muscle is mediated by EP(1) receptors in human colon and by a combination of EP(1) and EP(3) receptors in mouse intestine, whereas EP(2) receptors modulate relaxation in all three preparations. © 2011 Blackwell Publishing Ltd.
Express-evaluation of the psycho-physiological condition of Paralympic athletes
Drozdovski, Alexander; Gromova, Irina; Korotkov, Konstantin; Shelkov, Oleg; Akinnagbe, Femi
2012-01-01
Objective Evaluation of elite athletes’ psycho-physiological condition at various stages of preparation and in international competition. Design Athletes were tested during training and participation in international competition using methods of galvanic skin response (GSR) and gas discharge visualization (GDV). Setting Saint Petersburg Federal Research Institute of Physical Culture and Sport, Russia and Paralympic athletic training camp, Norway. Participants Eighteen athletes from Russia’s Skiing and Biathlon Paralympic Team. All athletes had some level of damage to their musculoskeletal system. Main outcome measures Stress level (SL), energy potential (EP), and psycho-emotional tension (PET). Results It was found that the higher the level of EP achieved by the athlete in the training period, the lower the SL in the competition time. The SL of an athlete recorded in the training period significantly correlates with the SL both before and at the time of competition. The PET and SL before the World Cup was negatively correlated to the results of skiing competitions. Conclusion Evaluation of PET, EP, and SL through GSR and GDV offers a fast, highly precise, non-invasive method to assess an athlete’s level of readiness during both training and at the time of competition. PMID:24198605
Engaging healthcare providers to implement HIV pre-exposure prophylaxis.
Krakower, Douglas; Mayer, Kenneth H
2012-11-01
Recent randomized controlled trials have demonstrated that HIV pre-exposure prophylaxis (PrEP) can decrease HIV incidence among several at-risk populations, including men who have sex with men, serodiscordant couples, and heterosexual men and women. As PrEP is a biomedical intervention that requires clinical monitoring and a high level of medication adherence, maximizing the public health effectiveness of PrEP in real-world settings will require the training of a cadre of healthcare providers to prescribe PrEP. Therefore it is critical to understand provider knowledge, practices, and attitudes towards PrEP prescribing, and to develop strategies for engaging and training providers to provide PrEP. Limited numbers of studies have focused on PrEP implementation by healthcare providers. These studies suggest that some providers are knowledgeable about PrEP, but many are not, or express misgivings. Although many clinicians report willingness to provide PrEP, few have prescribed PrEP in clinical practice. Provider comfort and skills in HIV risk assessment are suboptimal, which could limit identification of individuals who are most likely to benefit from PrEP use. Further studies to understand facilitators and barriers to HIV-risk assessment and PrEP prescribing by practicing clinicians are needed. Innovative training strategies and decision-support interventions for providers could optimize PrEP implementation and therefore merit additional research.
Plasma physics abstracts, 1 January - 31 December 1971
NASA Technical Reports Server (NTRS)
Montgomery, D. C.; Gurnett, D. A.
1971-01-01
Abstracts are presented on various aspects of plasma physics, including theoretical discussions and ionospheric plasmas. The topics considered cover Alfven waves, magnetized plasmas, plasma diffusion, Poynting flux measurements, electric fields, the magnetosphere, auroras, and plasma convection.
Jarrott, L. C.; McGuffey, C.; Beg, F. N.; ...
2017-10-24
Fast electron transport and spatial energy deposition are investigated in integrated cone-guided Fast Ignition experiments by measuring fast electron induced copper K-shell emission using a copper tracer added to deuterated plastic shells with a geometrically reentrant gold cone. Experiments were carried out at the Laboratory for Laser Energetics on the OMEGA/OMEGA-EP Laser where the plastic shells were imploded using 54 of the 60 OMEGA60 beams (3ω, 20 kJ), while the high intensity OMEGA-EP (BL2) beam (1 ω, 10 ps, 500 J, I peak > 10 19 W/cm 2) was focused onto the inner cone tip. Here, a retrograde analysis usingmore » the hybrid-PIC electron transport code, ZUMA, is performed to examine the sensitivity of the copper Kα spatial profile on the laser-produced fast electrons, facilitating the optimization of new target point designs and laser configurations to improve the compressed core areal density by a factor of 4 and the fast electron energy coupling by a factor of 3.5.« less
Lampignano, Rita; Yang, Liwen; Neumann, Martin H. D.; Franken, André; Fehm, Tanja; Niederacher, Dieter; Neubauer, Hans
2017-01-01
Circulating tumor cells (CTCs), potential precursors of most epithelial solid tumors, are mainly enriched by epithelial cell adhesion molecule (EpCAM)-dependent technologies. Hence, these approaches may overlook mesenchymal CTCs, considered highly malignant. Our aim was to establish a workflow to enrich and isolate patient-matched EpCAMhigh and EpCAMlow/negative CTCs within the same blood samples, and to investigate the phosphatidylinositol 3-kinase catalytic subunit alpha (PIK3CA) mutational status within single CTCs. We sequentially processed metastatic breast cancer (MBC) blood samples via CellSearch® (EpCAM-based) and via Parsortix™ (size-based) systems. After enrichment, cells captured in Parsortix™ cassettes were stained in situ for nuclei, cytokeratins, EpCAM and CD45. Afterwards, sorted cells were isolated via CellCelector™ micromanipulator and their genomes were amplified. Lastly, PIK3CA mutational status was analyzed by combining an amplicon-based approach with Sanger sequencing. In 54% of patients′ blood samples both EpCAMhigh and EpCAMlow/negative cells were identified and successfully isolated. High genomic integrity was observed in 8% of amplified genomes of EpCAMlow/negative cells vs. 28% of EpCAMhigh cells suggesting an increased apoptosis in the first CTC-subpopulation. Furthermore, PIK3CA hotspot mutations were detected in both EpCAMhigh and EpCAMlow/negative CTCs. Our workflow is suitable for single CTC analysis, permitting—for the first time—assessment of the heterogeneity of PIK3CA mutational status within patient-matched EpCAMhigh and EpCAMlow/negative CTCs. PMID:28858218
Jayathilake, Pahala G; Jana, Saikat; Rushton, Steve; Swailes, David; Bridgens, Ben; Curtis, Tom; Chen, Jinju
2017-01-01
The production of extracellular polymeric substance (EPS) is important for the survival of biofilms. However, EPS production is costly for bacteria and the bacterial strains that produce EPS (EPS+) grow in the same environment as non-producers (EPS-) leading to competition between these strains for nutrients and space. The outcome of this competition is likely to be dependent on factors such as initial attachment, EPS production rate, ambient nutrient levels and quorum sensing. We use an Individual-based Model (IbM) to study the competition between EPS+ and EPS- strains by varying the nature of initial colonizers which can either be in the form of single cells or multicellular aggregates. The microbes with EPS+ characteristics obtain a competitive advantage if they initially colonize the surface as smaller aggregates and are widely spread-out between the cells of EPS-, when both are deposited on the substratum. Furthermore, the results show that quorum sensing-regulated EPS production may significantly reduce the fitness of EPS producers when they initially deposit as aggregates. The results provide insights into how the distribution of bacterial aggregates during initial colonization could be a deciding factor in the competition among different strains in biofilms.
The Dutch EPS Registry: increasing the knowledge of encapsulating peritoneal sclerosis.
Korte, M R; Boeschoten, E W; Betjes, M G H
2009-09-01
Encapsulating peritoneal sclerosis (EPS) is a rare condition characterised by fibrotic thickening of the visceral peritoneum, leading to encapsulating of the intestines with partial or total intestinal obstruction. EPS is a serious complication of peritoneal dialysis (PD) with high morbidity and a mortality exceeding 50%. At present, there is uncertainty concerning the incidence and the risk factors involved in the development of EPS. To address these questions a nationwide registry has been initiated. The primary goals of the registry are to record the incidence of EPS and investigate the association of different variables, such as PD duration, medication, dialysis solutions and kidney transplantation with EPS. The registry will improve the knowledge of EPS and will serve to develop guidelines and necessary management strategies. From the registry different research activities can be initiated. A major challenge lies in the establishment of criteria that allow a timely diagnosis of EPS. At present, there are no diagnostic tools that can accurately detect EPS at an early stage. For this reason, besides patients with proven EPS, the clinical suspicion of EPS will be a sufficient criterion for inclusion in the registry. This nationwide EPS registry is currently enrolling patients.
Summer Research Experiences with a Laboratory Tokamak
NASA Astrophysics Data System (ADS)
Farley, N.; Mauel, M.; Navratil, G.; Cates, C.; Maurer, D.; Mukherjee, S.; Shilov, M.; Taylor, E.
1998-11-01
Columbia University's Summer Research Program for Secondary School Science Teachers seeks to improve middle and high school student understanding of science. The Program enhances science teachers' understanding of the practice of science by having them participate for two consecutive summers as members of laboratory research teams led by Columbia University faculty. In this poster, we report the research and educational activities of two summer internships with the HBT-EP research tokamak. Research activities have included (1) computer data acquisition and the representation of complex plasma wave phenomena as audible sounds, and (2) the design and construction of pulsed microwave systems to experience the design and testing of special-purpose equipment in order to achieve a specific technical goal. We also present an overview of the positive impact this type of plasma research involvement has had on high school science teaching.
Equilibrium statistical mechanics of self-consistent wave-particle system
NASA Astrophysics Data System (ADS)
Elskens, Yves
2005-10-01
The equilibrium distribution of N particles and M waves (e.g. Langmuir) is analysed in the weak-coupling limit for the self-consistent hamiltonian model H = ∑rpr^2 /(2m) + ∑jφjIj+ ɛ∑r,j(βj/ kj) (kjxr- θj) [1]. In the canonical ensemble, with temperature T and reservoir velocity v < jφj/kj, the wave intensities are almost independent and exponentially distributed, with expectation
NASA Astrophysics Data System (ADS)
Nelson, B. A.; Akcay, C.; Glasser, A. H.; Hansen, C. J.; Jarboe, T. R.; Marklin, G. J.; Milroy, R. D.; Morgan, K. D.; Norgaard, P. C.; Shumlak, U.; Sutherland, D. A.; Victor, B. S.; Sovinec, C. R.; O'Bryan, J. B.; Held, E. D.; Ji, J.-Y.; Lukin, V. S.
2014-10-01
The Plasma Science and Innovation Center (PSI-Center - http://www.psicenter.org) supports collaborating validation platform experiments with 3D extended MHD simulations using the NIMROD, HiFi, and PSI-TET codes. Collaborators include the Bellan Plasma Group (Caltech), CTH (Auburn U), HBT-EP (Columbia), HIT-SI (U Wash-UW), LTX (PPPL), MAST (Culham), Pegasus (U Wisc-Madison), SSX (Swarthmore College), TCSU (UW), and ZaP/ZaP-HD (UW). The PSI-Center is exploring application of validation metrics between experimental data and simulations results. Biorthogonal decomposition (BOD) is used to compare experiments with simulations. BOD separates data sets into spatial and temporal structures, giving greater weight to dominant structures. Several BOD metrics are being formulated with the goal of quantitive validation. Results from these simulation and validation studies, as well as an overview of the PSI-Center status will be presented.
Dependence of toxicity of silver nanoparticles on Pseudomonas putida biofilm structure.
Thuptimdang, Pumis; Limpiyakorn, Tawan; Khan, Eakalak
2017-12-01
Susceptibility of biofilms with different physical structures to silver nanoparticles (AgNPs) was studied. Biofilms of Pseudomonas putida KT2440 were formed in batch conditions under different carbon sources (glucose, glutamic acid, and citrate), glucose concentrations (5 and 50 mM), and incubation temperatures (25 and 30 °C). The biofilms were observed using confocal laser scanning microscopy for their physical characteristics (biomass amount, thickness, biomass volume, surface to volume ratio, and roughness coefficient). The biofilms forming under different growth conditions exhibited different physical structures. The biofilm thickness and the roughness coefficient were found negatively and positively correlated with the biofilm susceptibility to AgNPs, respectively. The effect of AgNPs on biofilms was low (1-log reduction of cell number) when the biofilms had high biomass amount, high thickness, high biomass volume, low surface to volume ratio, and low roughness coefficient. Furthermore, the extracellular polymeric substance (EPS) stripping process was applied to confirm the dependence of susceptibility to AgNPs on the structure of biofilm. After the EPS stripping process, the biofilms forming under different conditions showed reduction in thickness and biomass volume, and increases in surface to volume ratio and roughness coefficient, which led to more biofilm susceptibility to AgNPs. The results of this study suggest that controlling the growth conditions to alter the biofilm physical structure is a possible approach to reduce the impact of AgNPs on biofilms in engineered and natural systems. Copyright © 2017 Elsevier Ltd. All rights reserved.
Wang, Bin-Bin; Liu, Xue-Ting; Chen, Jian-Meng; Peng, Dang-Cong; He, Feng
2018-02-01
Characteristics of extracellular polymeric substances (EPS) in activated sludge strongly depend on wastewater substrates. Proteinaceous substrates (ProS) present in heterogeneous polymeric form are intrinsic and important parts of wastewater substrates for microorganisms in activated sludge systems. However, correlations between ProS and characteristics of EPS are scarce. This study systematically explored the impacts of monomeric (Mono-), low polymeric (LoP-) and high polymeric (HiP-) ProS on compositions and functional groups of EPS in activated sludge. The results showed that the change of polymerization degree of ProS significantly altered the composition of EPS. Compared to EPS Mono-ProS , the proportion of proteins in EPS LoP-ProS and EPS HiP-ProS increased by 12.8% and 27.7%, respectively, while that of polysaccharides decreased by 22.9% and 63.6%, respectively. Moreover, the proportion of humic compounds in EPS LoP-ProS and EPS HiP-ProS were ∼6 and ∼16-fold higher than that in EPS Mono-ProS , respectively. The accumulation of humic compounds in EPS increased the unsaturation degree of EPS molecules, and thereby reduced the energy requirement for electrons transition of amide bonds and aromatic groups. Size exclusion chromatography (SEC) analyses detected more molecular clusters in EPS HiP-ProS , indicating more complex composition of EPS in HiP-ProS fed activated sludge. Spectroscopic characterization revealed the dominance of hydrocarbon, protein, polysaccharide and aromatic associated bonds in all three EPS. Nevertheless, with the increase of polymerization degree of ProS, the protein associated bonds (such as CONH, CO, NC, NH) increased, while the polysaccharide associated bonds (such as COC, COH, OCOH) decreased. This paper paves a path to understand the role of ProS in affecting the production and characteristics of EPS in biological wastewater treatment systems. Copyright © 2017 Elsevier Ltd. All rights reserved.
Ceyhan, Nur; Ozdemir, Guven
2008-01-01
The extracellular polymers (EPS) of biofilm bacteria that can cause heat and mass transfer problems in cooling water towers in the petrochemical industry were investigated. In addition, these microorganisms were screened for their ability to grow and degrade their own EPS and the EPS of other species. Twelve bacteria producing the most EPS were isolated from cooling water towers and characterized biochemically by classic and commercial systems. These were species of Pseudomonas, Burkholderia, Aeromonas, Pasteurella, Pantoea, Alcaligenes and Sphingomonas. EPS of these species were obtained by propan-2-ol precipitation and centrifugation from bacterial cultures in media enriched with glucose, sucrose or galactose. EPS yields were of 1.68-4.95 g l(-1). These EPS materials were characterized for total sugar and protein contents. Their total sugar content ranged from 24 to 56% (g sugar g(-1) EPS), and their total protein content ranged from 10 to 28% (g protein g(-1) EPS). The monosaccharide compositions of EPS were determined by HPLC. Generally, these compositions were enriched in galactose and glucose, with lesser amounts of mannose, rhamnose, fructose and arabinose. All bacteria were investigated in terms of EPS degradation. Eight of the bacteria were able to utilize EPS from Burkholderia cepacia, seven of the bacteria were able to utilize EPS from Pseudomonas sp. and Sphingomonas paucimobilis. The greatest viscosity reduction of B. cepacia was obtained with Pseudomonas sp. The results show that the bacteria in this study are able to degrade EPS from biofilms in cooling towers.
Optical Aptamer Probes of Fluorescent Imaging to Rapid Monitoring of Circulating Tumor Cell
Hwang, Ji Yeon; Kim, Sang Tae; Han, Ho-Seong; Kim, Kyunggon; Han, Jin Soo
2016-01-01
Fluorescence detecting of exogenous EpCAM (epithelial cell adhesion molecule) or muc1 (mucin1) expression correlated to cancer metastasis using nanoparticles provides pivotal information on CTC (circulating tumor cell) occurrence in a noninvasive tool. In this study, we study a new skill to detect extracellular EpCAM/muc1 using quantum dot-based aptamer beacon (QD-EpCAM/muc1 ALB (aptamer linker beacon). The QD-EpCAM/muc1 ALB was designed using QDs (quantum dots) and probe. The EpCAM/muc1-targeting aptamer contains a Ep-CAM/muc1 binding sequence and BHQ1 (black hole quencher 1) or BHQ2 (black hole quencher2). In the absence of target EpCAM/muc1, the QD-EpCAM/muc1 ALB forms a partial duplex loop-like aptamer beacon and remained in quenched state because the BHQ1/2 quenches the fluorescence signal-on of the QD-EpCAM/muc1 ALB. The binding of EpCAM/muc1 of CTC to the EpCAM/muc1 binding aptamer sequence of the EpCAM/muc1-targeting oligonucleotide triggered the dissociation of the BHQ1/2 quencher and subsequent signal-on of a green/red fluorescence signal. Furthermore, acute inflammation was stimulated by trigger such as caerulein in vivo, which resulted in increased fluorescent signal of the cy5.5-EpCAM/muc1 ALB during cancer metastasis due to exogenous expression of EpCAM/muc1 in Panc02-implanted mouse model. PMID:27886058
Bai, Leilei; Xu, Huacheng; Wang, Changhui; Deng, Jiancai; Jiang, Helong
2016-11-01
Phytoplankton-derived extracellular polymeric substances (EPS) are of vital importance for the biogeochemical cycles of hydrophobic organic pollutants in lake ecosystems. In this study, roles of loosely-bound EPS (LB-EPS) and tightly bound EPS (TB-EPS) in biosorption of phenanthrene (PHE) on a typical cyanobacteria Microcystis aeruginosa were investigated. The results showed that the biosorption of PHE on M. aeruginosa cell varied lasted 24 h, while the binding of PHE to LB-EPS and TB-EPS reached equilibrium within less than 2 h. The equilibrium biosorption capacities of M. aeruginosa cell, LB-EPS and TB-EPS were 6.78, 12.31, and 9.47 μg mg(-1), respectively, indicating that the binding of PHE to EPS was a considerable process involved in biosorption. Fluorescence quenching titration revealed that increasing temperature induced more binding sites in EPS for PHE and the binding process was driven by electrostatic force and hydrophobic interactions. Interestingly, dynamic and static quenching processes occurred simultaneously for the binding of PHE to protein-like substances in EPS, whereas the binding of PHE to humic-like substances belonged to static quenching. The relatively higher contents of proteins in LB-EPS produced a stronger binding capacity of PHE. Overall, the interactions between hydrophobic organic pollutants and cyanobacterial EPS are favorable to the bioaccumulation of hydrophobic organic pollutants in cyanobacteria and facilitate the regulatory function of cyanobacterial biomass as a biological pump. Copyright © 2016 Elsevier Ltd. All rights reserved.
Guo, Caili; Sun, Xiaomin; Wang, Xiaowen; Guo, Qing; Chen, Dan
2018-01-01
This study aims to compare placebo (PBO) and 7 therapeutic regimens-namely, bronchodilator agents (BAs), hypertonic saline (HS), BA ± HS, corticosteroids (CS), epinephrine (EP), EP ± CS, and EP ± HS-to determine the optimal bronchiolitis treatment. We plotted networks using the curative outcome of several studies and specified the relations among the experiments by using mean difference, standardized mean difference, and corresponding 95% credible interval. The surface under the cumulative ranking curve (SUCRA) was used to separately rank each therapy on clinical severity score (CSS) and length of hospital stay (LHS). This network meta-analysis included 40 articles from 1995 to 2016 concerning the treatment of bronchiolitis in children. All 7 therapeutic regimens displayed no significant difference to PBO with regard to CSS in our study. Among the 7 therapies, BA performed better than CS. As for LHS, EP and EP ± HS had an advantage over PBO. Moreover, EP and EP ± HS were also more efficient than BA. The SUCRA results showed that EP ± CS is most effective, and EP ± HS is second most effective with regard to CSS. With regard to LHS, EP ± HS ranked first, EP ± CS ranked second, and EP ranked third. We recommend EP ± CS and EP ± HS as the first choice for bronchiolitis treatment in children because of their outstanding performance with regard to CSS and LHS. © 2017 American Society for Parenteral and Enteral Nutrition.
Charging of Space Debris and Their Dynamical Consequences
2016-01-08
field of plasmas and space physics . 15. SUBJECT TERMS Space Plasma Physics , Space Debris 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT...opens up potential new areas of fundamental and applied research in the field of plasmas and space physics ...object in a plasma”, accepted for publication in Physics of Plasmas. (attached as Annexure III) For details on (iv) please refer to the
E-type prostanoid receptor 4 (EP4) in disease and therapy
Konya, Viktoria; Marsche, Gunther; Schuligoi, Rufina; Heinemann, Akos
2013-01-01
The large variety of biological functions governed by prostaglandin (PG) E2 is mediated by signaling through four distinct E-type prostanoid (EP) receptors. The availability of mouse strains with genetic ablation of each EP receptor subtype and the development of selective EP agonists and antagonists have tremendously advanced our understanding of PGE2 as a physiologically and clinically relevant mediator. Moreover, studies using disease models revealed numerous conditions in which distinct EP receptors might be exploited therapeutically. In this context, the EP4 receptor is currently emerging as most versatile and promising among PGE2 receptors. Anti-inflammatory, anti-thrombotic and vasoprotective effects have been proposed for the EP4 receptor, along with its recently described unfavorable tumor-promoting and pro-angiogenic roles. A possible explanation for the diverse biological functions of EP4 might be the multiple signaling pathways switched on upon EP4 activation. The present review attempts to summarize the EP4 receptor-triggered signaling modules and the possible therapeutic applications of EP4-selective agonists and antagonists. PMID:23523686
Lee, Hyo-Chang; Chung, Chin-Wook
2015-10-20
Hysteresis, which is the history dependence of physical systems, is one of the most important topics in physics. Interestingly, bi-stability of plasma with a huge hysteresis loop has been observed in inductive plasma discharges. Despite long plasma research, how this plasma hysteresis occurs remains an unresolved question in plasma physics. Here, we report theory, experiment, and modeling of the hysteresis. It was found experimentally and theoretically that evolution of the electron energy distribution (EED) makes a strong plasma hysteresis. In Ramsauer and non-Ramsauer gas experiments, it was revealed that the plasma hysteresis is observed only at high pressure Ramsauer gas where the EED deviates considerably from a Maxwellian shape. This hysteresis was presented in the plasma balance model where the EED is considered. Because electrons in plasmas are usually not in a thermal equilibrium, this EED-effect can be regarded as a universal phenomenon in plasma physics.
Lee, Hyo-Chang; Chung, Chin-Wook
2015-01-01
Hysteresis, which is the history dependence of physical systems, is one of the most important topics in physics. Interestingly, bi-stability of plasma with a huge hysteresis loop has been observed in inductive plasma discharges. Despite long plasma research, how this plasma hysteresis occurs remains an unresolved question in plasma physics. Here, we report theory, experiment, and modeling of the hysteresis. It was found experimentally and theoretically that evolution of the electron energy distribution (EED) makes a strong plasma hysteresis. In Ramsauer and non-Ramsauer gas experiments, it was revealed that the plasma hysteresis is observed only at high pressure Ramsauer gas where the EED deviates considerably from a Maxwellian shape. This hysteresis was presented in the plasma balance model where the EED is considered. Because electrons in plasmas are usually not in a thermal equilibrium, this EED-effect can be regarded as a universal phenomenon in plasma physics. PMID:26482650
Extended MHD modeling of nonlinear instabilities in fusion and space plasmas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Germaschewski, Kai
A number of different sub-projects where pursued within this DOE early career project. The primary focus was on using fully nonlinear, curvilinear, extended MHD simulations of instabilities with applications to fusion and space plasmas. In particular, we performed comprehensive studies of the dynamics of the double tearing mode in different regimes and confi gurations, using Cartesian and cyclindrical geometry and investigating both linear and non-linear dynamics. In addition to traditional extended MHD involving Hall term and electron pressure gradient, we also employed a new multi-fluid moment model, which shows great promise to incorporate kinetic effects, in particular off-diagonal elements ofmore » the pressure tensor, in a fluid model, which is naturally computationally much cheaper than fully kinetic particle or Vlasov simulations. We used our Vlasov code for detailed studies of how weak collisions effect plasma echos. In addition, we have played an important supporting role working with the PPPL theory group around Will Fox and Amitava Bhattacharjee on providing simulation support for HED plasma experiments performed at high-powered laser facilities like OMEGA-EP in Rochester, NY. This project has support a great number of computational advances in our fluid and kinetic plasma models, and has been crucial to winning multiple INCITE computer time awards that supported our computational modeling.« less
Erect panicle2 encodes a novel protein that regulates panicle erectness in indica rice.
Zhu, Keming; Tang, Ding; Yan, Changjie; Chi, Zhengchang; Yu, Hengxiu; Chen, Jianmin; Liang, Jiansheng; Gu, Minghong; Cheng, Zhukuan
2010-02-01
Rice (Oryza sativa L.) inflorescence (panicle) architecture is an important agronomic trait for rice breeding. A number of high-yielding japonica rice strains, characterized by an erect panicle (EP) of their architecture, have been released as commercial varieties in China. But no EP-type indica varieties are released so far. Here, we identified two allelic erect-panicle mutants in indica rice, erect panicle2-1 (ep2-1) and erect panicle2-2 (ep2-2), exhibiting the characteristic erect panicle phenotype. Both mutants were derived from spontaneous mutation. We cloned the EP2 gene by way of a map-based cloning strategy, and a transgenic complementation test rescued the phenotype of ep2-1. Anatomical investigations revealed that the ep2 mutants have more vascular bundles and a thicker stem than that of wild-type plants, explaining the panicle erectness phenotype in ep2 mutants. It was shown that EP2 was specifically expressed in the vascular bundles of internodes by GUS staining and RT-PCR. EP2 encodes a novel plant-specific protein, which localizes to the endoplasmic reticulum with unknown biochemical function. In addition, EP2 also regulates other panicle characteristics, such as panicle length and grain size, but grain number per panicle shows little change, indicating that the mutation of the ep2 gene could be applied in EP-type indica rice breeding.
Tayama, Shingo; Motohara, Takeshi; Narantuya, Dashdemberel; Li, Chenyan; Fujimoto, Koichi; Sakaguchi, Isao; Tashiro, Hironori; Saya, Hideyuki; Nagano, Osamu; Katabuchi, Hidetaka
2017-07-04
Epithelial ovarian cancer is a highly lethal malignancy; moreover, overcoming chemoresistance is the major challenging in treating ovarian cancer patients. The cancer stem cell (CSC) hypothesis considers CSCs to be the main culprits in driving tumor initiation, metastasis, and resistance to conventional therapy. Although growing evidence suggest that CSCs are responsible for chemoresistance, the contribution of CSC marker EpCAM to resistance to chemotherapy remains unresolved.Here we have demonstrated that ovarian cancers containing high levels of EpCAM have a significantly much lower probability of achieving overall responsive rates after first-line chemotherapy. In addition, multivariate analysis revealed that EpCAM expression is an independent risk factor for chemoresistance, indicating that EpCAM expression is a predictive biomarker of chemotherapeutic response. Consistent with these clinical observations, in vitro assays, we found that the subpopulation of EpCAM-positive ovarian cancer cells shows a significantly higher viability compared with EpCAM-negative cells in response to cisplatin treatment by preventing chemotherapy-induced apoptosis, which is regulated by EpCAM-Bcl-2 axis. Furthermore, in an in vivo mouse model, platinum agents preferentially eliminated EpCAM-negative cells in comparison with EpCAM-positive cells, suggesting that the remaining subpopulation of EpCAM-positive cells contributes to tumor recurrence after chemotherapy. Finally, we also found that an increased expression of EpCAM is associated with poor prognosis in ovarian cancer patients.Our findings highlight the clinical significance of EpCAM in the resistance to chemotherapy and provide a rationale for EpCAM-targeted therapy to improve chemoresistance. Targeting EpCAM should be a promising approach to effectively extirpate the CSCs as the putative root of ovarian cancer.
Jang, Mi; Shim, Won Joon; Han, Gi Myung; Rani, Manviri; Song, Young Kyoung; Hong, Sang Hee
2017-12-01
The role of marine plastic debris and microplastics as a carrier of hazardous chemicals in the marine environment is an emerging issue. This study investigated expanded polystyrene (EPS, commonly known as styrofoam) debris, which is a common marine debris item worldwide, and its additive chemical, hexabromocyclododecane (HBCD). To obtain a better understanding of chemical dispersion via EPS pollution in the marine environment, intensive monitoring of HBCD levels in EPS debris and microplastics was conducted in South Korea, where EPS is the predominant marine debris originate mainly from fishing and aquaculture buoys. At the same time, EPS debris were collected from 12 other countries in the Asia-Pacific region, and HBCD concentrations were measured. HBCD was detected extensively in EPS buoy debris and EPS microplastics stranded along the Korean coasts, which might be related to the detection of a quantity of HBCD in non-flame-retardant EPS bead (raw material). The wide detection of the flame retardant in sea-floating buoys, and the recycling of high-HBCD-containing EPS waste inside large buoys highlight the need for proper guidelines for the production and use of EPS raw materials, and the recycling of EPS waste. HBCD was also abundantly detected in EPS debris collected from the Asia-Pacific coastal region, indicating that HBCD contamination via EPS debris is a common environmental issue worldwide. Suspected tsunami debris from Alaskan beaches indicated that EPS debris has the potential for long-range transport in the ocean, accompanying the movement of hazardous chemicals. The results of this study indicate that EPS debris can be a source of HBCD in marine environments and marine food web. Copyright © 2017 Elsevier Ltd. All rights reserved.
Arnold, Trisha; Brinkley-Rubinstein, Lauren; Chan, Philip A; Perez-Brumer, Amaya; Bologna, Estefany S; Beauchamps, Laura; Johnson, Kendra; Mena, Leandro; Nunn, Amy
2017-01-01
Pre-exposure prophylaxis (PrEP) is a biomedical intervention that can reduce rates of HIV transmission when taken once daily by HIV-negative individuals. Little is understood about PrEP uptake and retention in care among the populations most heavily impacted by the HIV epidemic, particularly among young men who have sex with men (YMSM) in the Deep South. Therefore, this study explored the structural, social, behavioral, and clinical factors that affect PrEP use and retention in care among YMSM in Jackson, Mississippi. Thirty MSM who were prescribed PrEP at an outpatient primary care clinic were interviewed and included 23 men who had been retained in PrEP care and seven who had not been retained. The mean age of participants was 26.6 years. Most (23) participants were African American. Major factors affecting PrEP use and retention in PrEP care included 1) structural factors such as cost and access to financial assistance for medications and clinical services; 2) social factors such as stigma and relationship status; 3) behavioral factors including sexual risk behaviors; and 4) clinical factors such as perceived and actual side effects. Many participants also discussed the positive spillover effects of PrEP use and reported that PrEP had a positive impact on their health. Four of the seven individuals who had not been retained re-enrolled in PrEP care after completing their interviews, suggesting that case management and ongoing outreach can enhance retention in PrEP care. Interventions to enhance retention in PrEP care among MSM in the Deep South will be most effective if they address the complex structural, social, clinical, and behavioral factors that influence PrEP uptake and retention in PrEP care.
EpCAM expression in primary tumour tissues and metastases: an immunohistochemical analysis.
Spizzo, Gilbert; Fong, Dominic; Wurm, Martin; Ensinger, Christian; Obrist, Peter; Hofer, Carina; Mazzoleni, Guido; Gastl, Guenther; Went, Philip
2011-05-01
Epithelial cell adhesion molecule (EpCAM) is a cell surface protein with oncogenic features that is expressed on healthy human epithelia and corresponding malignant tumours. EpCAM expression frequently correlates with more aggressive tumour behaviour and new EpCAM-specific therapeutic agents have recently been approved for clinical use in patients with cancer. However, no consensus exists on how and when to evaluate EpCAM expression in patients with cancer. EpCAM expression was assessed by a well-established immunohistochemical staining protocol in 2291 primary tumour tissues and in 108 metastases using the EpCAM-specific antibody clone VU1D9. A total immunostaining score was calculated as the product of a proportion score and an intensity score. Four expression subgroups (no, weak, moderate and intense) were defined. As described previously, the term 'EpCAM overexpression' was reserved for tissues showing a total immunostaining score >4. EpCAM was highly expressed in most tumours of gastrointestinal origin and in some carcinomas of the genitourinary tract. However, hepatocellular carcinomas, clear cell renal cell cancer, urothelial cancer and squamous cell cancers were frequently EpCAM negative. EpCAM expression in breast cancer depended on the histological subtype; lobular histology usually showed no or weak expression. Most metastases were EpCAM positive and they frequently reflected the expression phenotype of the primary tumour. EpCAM expression was detected on adenocarcinomas of various primary sites. If EpCAM-specific antibodies are intended to be used in patients with cancer, we recommend prior immunohistochemical evaluation of EpCAM expression, particularly in patients with renal cell cancer, hepatocellular carcinoma, urothelial carcinoma, breast cancer and squamous cell carcinomas.
Mullins, Tanya L Kowalczyk; Zimet, Gregory; Lally, Michelle; Xu, Jiahong; Thornton, Sarah; Kahn, Jessica A
2017-12-01
Pre-exposure prophylaxis (PrEP) is indicated for use in US adults, and little is known about clinician intentions to prescribe and actual prescription of PrEP to adolescents younger than 18. Fifty-six clinicians who care for HIV-infected and at-risk youth completed an anonymous online survey in 2014. Primary outcomes were (1) intentions to prescribe PrEP to adolescents and adults in four risk categories [men who have sex with men (MSM), transgender women, heterosexuals with multiple partners of unknown HIV status, heterosexuals with HIV-infected partners]; and (2) actual prescription of PrEP to adolescents and adults in these risk groups. Independent variables included clinician characteristics, experience prescribing nonoccupational postexposure prophylaxis, familiarity with and knowledge of PrEP and PrEP guidance, attitudes toward PrEP, and facilitating factors for prescribing PrEP and incorporation of PrEP guidance into practice. Variables associated with intention to prescribe ("very likely to prescribe" vs. other responses) and actual prescription of PrEP stratified by age and risk category were identified in logistic regression models. Mean age was 45.9 years (standard deviation 10.7); 64% were physicians. More clinicians reported high intention to prescribe PrEP to adult versus adolescent MSM (p = 0.02) and transgender women (p = 0.001). Variables associated with intention to prescribe and prescription of PrEP differed by age and risk category. In adolescents, those variables included positive beliefs, higher number of facilitating factors, and fewer barriers to PrEP prescription. Designing strategies based on these findings that address both facilitating factors and barriers to PrEP prescription may improve PrEP uptake by at-risk youth.
Pintye, Jillian; Beima-Sofie, Kristin M; Kimemia, Grace; Ngure, Kenneth; Trinidad, Susan Brown; Heffron, Renee A; Baeten, Jared M; Odoyo, Josephine; Mugo, Nelly; Bukusi, Elizabeth A; Kelley, Maureen C; John-Stewart, Grace C
2017-11-01
The perceptions, motivations, and beliefs of HIV-uninfected women about pre-exposure prophylaxis (PrEP) use during pregnancy can influence its uptake and adherence. This study elicited the views of HIV-uninfected women with personal experience taking PrEP during pregnancy. Qualitative interviews were conducted with HIV-uninfected women who had personal experience taking PrEP while pregnant. Semistructured interviews were conducted with 21 HIV-uninfected Kenyan women in HIV-serodiscordant couples enrolled in an open-label PrEP demonstration project who became pregnant while using PrEP and continued PrEP through their pregnancy. Interviews were audio-recorded and transcribed into English. A qualitative descriptive analysis was performed, using a constant comparison approach to identify key themes related to PrEP use in pregnancy. Desire to remain HIV uninfected and have an HIV-free infant were strong motivators influencing continued use of PrEP during pregnancy. Supporting HIV-infected partners and childbearing within an HIV-serodiscordant relationship were also motivators. Women had challenges distinguishing normal pregnancy symptoms from PrEP side effects and were concerned that observed side effects could be signs of danger for the infant related to PrEP exposure. Health care providers were important conduits of knowledge about PrEP, and continuity of PrEP providers throughout pregnancy facilitated adherence. HIV-uninfected women in HIV-serodiscordant couples were motivated to use PrEP during pregnancy to remain HIV uninfected and to have an HIV-free child but had concerns about side effects. Health care providers will be important for PrEP messaging and adherence support in this unique population.
Säfholm, J; Dahlén, S-E; Delin, I; Maxey, K; Stark, K; Cardell, L-O; Adner, M
2013-01-01
Background and Purpose The guinea pig trachea (GPT) is commonly used in airway pharmacology. The aim of this study was to define the expression and function of EP receptors for PGE2 in GPT as there has been ambiguity concerning their role. Experimental Approach Expression of mRNA for EP receptors and key enzymes in the PGE2 pathway were assessed by real-time PCR using species-specific primers. Functional studies of GPT were performed in tissue organ baths. Key Results Expression of mRNA for the four EP receptors was found in airway smooth muscle. PGE2 displayed a bell-shaped concentration–response curve, where the initial contraction was inhibited by the EP1 receptor antagonist ONO-8130 and the subsequent relaxation by the EP2 receptor antagonist PF-04418948. Neither EP3 (ONO-AE5-599) nor EP4 (ONO-AE3-208) selective receptor antagonists affected the response to PGE2. Expression of COX-2 was greater than COX-1 in GPT, and the spontaneous tone was most effectively abolished by selective COX-2 inhibitors. Furthermore, ONO-8130 and a specific PGE2 antibody eliminated the spontaneous tone, whereas the EP2 antagonist PF-04418948 increased it. Antagonists of other prostanoid receptors had no effect on basal tension. The relaxant EP2 response to PGE2 was maintained after long-term culture, whereas the contractile EP1 response showed homologous desensitization to PGE2, which was prevented by COX-inhibitors. Conclusions and Implications Endogenous PGE2, synthesized predominantly by COX-2, maintains the spontaneous tone of GPT by a balance between contractile EP1 receptors and relaxant EP2 receptors. The model may be used to study interactions between EP receptors. PMID:22934927
Demographic differences in PrEP–related stereotypes: Implications for implementation
Golub, Sarit. A.; Gamarel, Kristi E.; Surace, Anthony
2015-01-01
Qualitative interviews about pre-exposure prophylaxis (PrEP) stereotypes were conducted with a subsample of 160 MSM who participated in a PrEP messaging study. Negative stereotypes about PrEP users were identified by 80% of participants. Two types of stereotypes were most common: PrEP users are HIV-infected (and lying about it), and PrEP users are promiscuous and resistant to condom use. Participants’ identification of these stereotype categories differed significantly by demographic factors (i.e. race/ethnicity, education). Expanding access to PrEP requires recognizing potential differences in the experience or anticipation of PrEP-related stereotypes that might impact willingness to discuss PrEP with providers, friends, or partners. PMID:26143247
The design and development of a space laboratory to conduct magnetospheric and plasma research
NASA Technical Reports Server (NTRS)
Rosen, A.
1974-01-01
A design study was conducted concerning a proposed shuttle-borne space laboratory for research on magnetospheric and plasma physics. A worldwide survey found two broad research disciplines of interest: geophysical studies of the dynamics and structure of the magnetosphere (including wave characteristics, wave-particle interactions, magnetospheric modifications, beam-plasma interactions, and energetic particles and tracers) and plasma physics studies (plasma physics in space, wake and sheath studies, and propulsion and devices). The Plasma Physics and Environmental Perturbation Laboratory (PPEPL) designed to perform experiments in these areas will include two 50-m booms and two maneuverable subsatellites, a photometer array, standardized proton, electron, and plasma accelerators, a high-powered transmitter for frequencies above 100 kHz, a low-power transmitter for VLF and below, and complete diagnostic packages. Problem areas in the design of a space plasma physics laboratory are indicated.
Plasma Physics at the National Science Foundation
NASA Astrophysics Data System (ADS)
Lukin, Vyacheslav
2017-10-01
The Town Meeting on Plasma Physics at the National Science Foundation will provide an opportunity for Q&A about the variety of NSF programs and solicitations relevant to a broad cross-section of the academic plasma science community, from graduating college seniors to senior leaders in the field, and from plasma astrophysics to basic physics to plasma engineering communities. We will discuss recent NSF-hosted events, research awards, and multi-agency partnerships aimed at enabling the progress of science in plasma science and engineering. Future outlook for plasma physics and broader plasma science support at NSF, with an emphasis on how you can help NSF to help the community, will be speculated upon within the uncertainty of the federal budgeting process.
Impact of insurance coverage on utilization of pre-exposure prophylaxis for HIV prevention.
Patel, Rupa R; Mena, Leandro; Nunn, Amy; McBride, Timothy; Harrison, Laura C; Oldenburg, Catherine E; Liu, Jingxia; Mayer, Kenneth H; Chan, Philip A
2017-01-01
Pre-exposure prophylaxis (PrEP) can reduce U.S. HIV incidence. We assessed insurance coverage and its association with PrEP utilization. We reviewed patient data at three PrEP clinics (Jackson, Mississippi; St. Louis, Missouri; Providence, Rhode Island) from 2014-2015. The outcome, PrEP utilization, was defined as patient PrEP use at three months. Multivariable logistic regression was performed to determine the association between insurance coverage and PrEP utilization. Of 201 patients (Jackson: 34%; St. Louis: 28%; Providence: 28%), 91% were male, 51% were White, median age was 29 years, and 21% were uninsured; 82% of patients reported taking PrEP at three months. Insurance coverage was significantly associated with PrEP utilization. After adjusting for Medicaid-expansion and individual socio-demographics, insured patients were four times as likely to use PrEP services compared to the uninsured (OR: 4.49, 95% CI: 1.68-12.01; p = 0.003). Disparities in insurance coverage are important considerations in implementation programs and may impede PrEP utilization.
Guo, Xinxin; Wang, Yili; Wang, Dongsheng
2017-11-01
A novel activated sludge (AS) conditioning method through permanganate/bisulfate (PM/BS) process was proposed. The method involved a new conditioner of reactive Mn(III) intermediate. Moreover, a Mn(III) conditioning-horizontal electro-dewatering (Mn(III) C-HED) process was established to improve AS dewatering performance. Underlying mechanisms were unraveled by investigating changes in physicochemical characteristics, scanning electron microscope (SEM) morphology, and transformation of water and organic matters. The optimum dewatering conditions for Mn(III) C-HED process with the final water content of 86.94% were determined as the combination of KMnO 4 0.01 mol/L AS and NaHSO 3 0.05 mol/L AS at 20 V for 120 min. Results showed that Mn(III) C-HED process effectively reduced free water and bound water with the corresponding removal ratios of 51.68% and 87.62% at the anode-side as well as 36.55% and 85.08% at the cathode-side, respectively. During the PM/BS process, the produced Mn(III), Mn 2+ , and MnO 2 exerted chemical and physical effects on AS conditioning and dewatering. Mn(III) disintegrated extracellular polymeric substances (EPS) fractions and cells in AS, as well as induced partial bound water release. Additionally, flocculation effect induced by Mn 2+ and MnO 2 skeleton building also benefited AS dewatering. AS cells were further disrupted under the effect of a horizontal electric field. Accordingly, EPS within the AS matrix was solubilized, tightly bound (TB)-EPS or loosely bound (LB)-EPS was converted to their corresponding outer EPS fractions, and AS dewaterability improved. Additionally, changes in pH and temperature at HED stage damaged the AS cells and changed the floc properties, thereby leading to easy separation of liquid and AS particles. Copyright © 2017 Elsevier Ltd. All rights reserved.
Inappropriate erythropoietin secretion in polycythemia vera
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chikkappa, G.; Burlington, H.; Chanana, A.D.
1977-01-01
A patient with classical polycythemia vera (PV) was found to have an inappropriately elevated serum erythropoietin (Ep) level. Investigations did not reveal any lesion or blood abnormality known to be associated with excessive Ep production and erythrocytosis. Sudden withdrawal of blood to reduce the Hb and Hct from 18.5 gm% and 56% to 13.6 gm% and 41.5%, respectively, resulted in an increment of serum Ep to abnormal level. With iron treatment there was a brisk return of Hb and Hct to prebleeding levels which was associated with reduction in the serum Ep. The inverse relationship between the EP and Hbmore » or Hct is inconsistent with the presence of excessive Ep-producing lesion. These results suggested that the threshold for Ep secretion from normal Ep-secreting tissue to Hb and Hct levels is set at an abnormal level. This patient's marrow cells when cultured in vitro in the absence of Ep, unlike other PV patients' (except one) marrow cells, did not grow erythroid colonies. In the presence of Ep, however, the colonies comparable to those formed from normal marrow cultures were obtained. These results suggested that his marrow erythropoietic cells were neither Ep independent nor Ep-hyperresponsive, as has been suggested by some investigators for erythropoiesis in PV. This patient presents phenomena that hitherto have not been reported.« less
Misoprostol, an anti-ulcer agent and PGE2 receptor agonist, protects against cerebral ischemia.
Li, Jun; Liang, Xibin; Wang, Qian; Breyer, Richard M; McCullough, Louise; Andreasson, Katrin
2008-06-20
Induction of COX-2 activity in cerebral ischemia results in increased neuronal injury and infarct size. Recent studies investigating neurotoxic mechanisms of COX-2 demonstrate both toxic and paradoxically protective effects of downstream prostaglandin receptor signaling pathways. We tested whether misoprostol, a PGE(2) receptor agonist that is utilized clinically as an anti-ulcer agent and signals through the protective PGE(2) EP2, EP3, and EP4 receptors, would reduce brain injury in the murine middle cerebral artery occlusion-reperfusion (MCAO-RP) model. Administration of misoprostol, at the time of MCAO or 2h after MCAO, resulted in significant rescue of infarct volume at 24 and 72h. Immunocytochemistry demonstrated dynamic regulation of the EP2 and EP4 receptors during reperfusion in neurons and endothelial cells of cerebral cortex and striatum, with limited expression of EP3 receptor. EP3-/- mice had no significant changes in infarct volume compared to control littermates. Moreover, administration of misoprostol to EP3+/+ and EP3-/- mice showed similar levels of infarct rescue, indicating that misoprostol protection was not mediated through the EP3 receptor. Taken together, these findings suggest a novel function for misoprostol as a protective agent in cerebral ischemia acting via the PGE(2) EP2 and/or EP4 receptors.
Observation of astrophysical Weibel instability in counterstreaming laser-produced plasmas
NASA Astrophysics Data System (ADS)
Fox, W.; Fiksel, G.; Bhattacharjee, A.; Germaschewski, K.; Chang, P.-Y.; Hu, S. X.; Nilson, P. M.
2013-10-01
Astrophysical shocks are typically collisionless and require collective electromagnetic fields to couple the upstream and downstream plasmas. The Weibel instability has been proposed to be one of such collective mechanism. Here we present laboratory tests of this process through observations of the Weibel instability generated between two counterstreaming, supersonic plasma flows, generated on the OMEGA EP laser facility by irradiating of a pair of opposing parallel CH targets by UV laser pulses (0.351 μm, 1.8 kJ, 2 ns). The Weibel-generated electromagnetic fields were probed with an ultrafast proton beam, generated with a high-intensity laser pulse (1.053 μm, 800 J, 10 ps) focused to >1018 W/cm2 onto a thin Cu disk. Growth of a striated, transverse instability is observed at the midplane as the two plasmas interpenetrate, which is identified as the Weibel instability through agreement with analytic theory and particle-in-cell simulations. These laboratory observations directly demonstrate the existence of this astrophysical process, and pave the way for further detailed laboratory study of this instability and its consequences for particle energization and shock formation. This work was supported by DOE grant DE-SC0007168.
NASA Astrophysics Data System (ADS)
Soto, Leopoldo
2011-07-01
The International Advisory Committee of the 15th International Congress on Plasma Physics (ICPP 2010) and the International Advisory Committee of the 13th Latin American Workshop on Plasma Physics (LAWPP 2010) both agreed to hold this combined meeting ICPP-LAWPP-2010 in Santiago de Chile, 8-13 August 2010, considering the celebration of the Bicentennial of Chilean Independence. ICPP-LAWPP-2010 was organized by the Thermonuclear Plasma Department of the Chilean Nuclear Energy Commission (CCHEN) as part of its official program, within the framework of the Chilean Bicentennial activities. This event was also a scientific and academic activity of the project `Center for Research and Applications in Plasma Physics and Pulsed Power, P4', supported by the National Scientific and Technological Commission, CONICYT-Chile, under grant ACT-26. The International Congress on Plasma Physics was first held in Nagoya in 1980, and was followed by: Gothenburg (1982), Lausanne (1984), Kiev (1987), New Delhi (1989), Innsbruck (1992), Foz do Iguacu (1994), Nagoya (1996), Prague (1998), Quebec City (2000), Sydney (2002), Nice (2004), Kiev (2006) and Fukuoka (2008). The purpose of the Congress is to discuss recent progress and outlooks in plasma science, covering fundamental plasma physics, fusion plasmas, astrophysical plasmas, plasma applications, etc. The Latin American Workshop on Plasma Physics was first held in 1982 in Cambuquira, Brazil, followed by: Medellín (1985), Santiago (1988), Buenos Aires (1990), Mexico City (1992), Foz do Iguacu (1994, also combined with ICPP), Caracas (1997), Tandil (1998), La Serena (2000), Sao Pedro (2003), Mexico City (2005) and Caracas (2007). The purpose of the Latin American Workshop on Plasma Physics is to provide a forum in which the achievements of the Latin American plasma physics communities can be displayed, as well as to foster collaboration between plasma scientists within the region and elsewhere. The Program of ICPP-LAWPP-2010 included, amongst others, the following topics: fundamentals of plasma physics, fusion plasmas, plasmas in astrophysics and space physics, plasma applications and technologies, complex plasmas, high energy density plasmas, quantum plasmas and laser-plasma interaction. A total of 180 delegates from 34 different countries took part in ICPP-LAWPP-2010, and 60 delegates received financial assistance from the Local Organizing Committee, thanks to the support granted by the International Union for Pure and Applied Physics (IUPAP) and by CCHEN. The ICPP-LAWPP-2010 Program was established by the following Program Committee: • Carlos Alejaldre, ITER • Maria Virginia Alves, Brazil • Julio Herrera, Mexico • Günter Mank, IAEA • George Morales, USA • Padma Kant Shukla, Germany • Guido Van Oost, Belgium • Leopoldo Soto, Chile (Chairman) This Program Committee was formed of selected members from the International Advisory Committee of the ICPP and from the International Advisory Committee of the LAWPP (http://www.icpp-lawpp-2010.cl/page/committees.php). In particular, plenary lectures and invited topical lectures were selected by the Program Committee from a list of nominated lectures presented by the International Advisory Committees of both ICPP and LAWPP. Also, the classification of oral and poster presentations was established by the Program Committee. The Congress included 15 invited plenary talks, 33 invited topical talks, 45 oral contributions, and 160 poster contributions. Most of the plenary and topical lectures are published in this special issue of Plasma Physics and Controlled Fusion. The papers were refereed according to the usual standards of the journal. Prior to ICPP-LAWPP 2010, an important activity usually associated with the Latin American Workshop on Plasma Physics took place. This activity was the LAWPP School on Plasma Physics, which was open to participants from all over the world, providing basic training to students and young researchers. The School was attended by 44 participants and 7 lecturers from 11 different countries. All participants received financial assistance from the Local Organizing Committee. The topics covered by the School were: a general description of plasmas, space and astrophysical plasmas, plasma diagnostic techniques, high temperature and fusion plasmas, and low temperature and industrial plasmas. The organizers of ICPP-LAWPP-2010 are grateful to the lecturers of the LAWPP Plasma Physics School: Luis Felipe Delgado-Aparicio (USA), Homero Maciel (Brazil), and Marina Stepanova, J Alejandro Valdivia, Victor Muñoz, Felipe Veloso and Leopoldo Soto (Chile). On 27 February 2010, Chile suffered a major earthquake, one of the worst in the recorded history of the world up to that time. Although Santiago was little affected, the region located 200 km to the south was seriously damaged. After this event, the Local Organizing Committee received many messages from members of the plasma physics community around the world expressing their concern. The Local Organizing Committee greatly appreciates the support of the participants from all over the world who decided to come to Chile to attend the Conference. Their solidarity is highly appreciated. The Chairman of ICPP-LAWPP-2010 is grateful to the members of the Local Organizing Committee for the conference: Karla Cubillos, José Moreno, Cristian Pavez, Felipe Veloso, Marcelo Zambra, Luis Huerta and Fabian Reyes, and to the members of the Program Committee for their work and commitment. The Guest Editor of this special issue is grateful to the Publishers, in particular to Caroline Wilkinson, for their excellent work and cooperation.
Lu, Qin; Chang, Ming; Yu, Zhen; Zhou, Shungui
2015-01-01
Recently, the redox properties of extracellular polymeric substances (EPS) have attracted the attention of scientists due to their associated environmental significance, such as organic pollutant (e.g. nitroaromatics and substituted nitrobenzenes) degradation and heavy metal (e.g. Cr(VI) and U(VI)) detoxification. Although the separation of EPS from bacterial cells is more often the first step in studies on EPS, and studies have demonstrated that extraction procedures can influence the sorption properties of EPS, few attempts have been made to investigate how separation methods affect the redox properties of the obtained EPS. In this study, three common extraction approaches, that is, centrifugation, formaldehyde+NaOH and ethylene diamine tetra-acetic acid (EDTA), were employed to extract EPS from activated sludge, and the obtained EPS were evaluated for their redox properties using electrochemical means, including cyclic voltammetry and chronoamperometry. In addition, spectroscopic techniques were utilized to explore the structural characteristics and composition of EPS. The results indicated that EPS extracted by EDTA clearly displayed reversible oxidation-reduction peaks in cyclic voltammograms and significantly higher electron-accepting capacity compared with EPS extracted using the other two approaches. Fourier transform infrared spectra and three-dimensional excitation-emission matrix spectra suggested that the EPS extracted with EDTA presented better redox properties because of the effective and efficient extraction of the humic substances, which are important components of the EPS of activated sludge. Therefore, extraction method has an impact on the composition and redox properties of EPS and should be chosen according to research purpose and EPS source.
Structure and biosynthesis of two exopolysaccharides produced by Lactobacillus johnsonii FI9785.
Dertli, Enes; Colquhoun, Ian J; Gunning, A Patrick; Bongaerts, Roy J; Le Gall, Gwénaëlle; Bonev, Boyan B; Mayer, Melinda J; Narbad, Arjan
2013-11-01
Exopolysaccharides were isolated and purified from Lactobacillus johnsonii FI9785, which has previously been shown to act as a competitive exclusion agent to control Clostridium perfringens in poultry. Structural analysis by NMR spectroscopy revealed that L. johnsonii FI9785 can produce two types of exopolysaccharide: EPS-1 is a branched dextran with the unusual feature that every backbone residue is substituted with a 2-linked glucose unit, and EPS-2 was shown to have a repeating unit with the following structure: -6)-α-Glcp-(1-3)-β-Glcp-(1-5)-β-Galf-(1-6)-α-Glcp-(1-4)-β-Galp-(1-4)-β-Glcp-(1-. Sites on both polysaccharides were partially occupied by substituent groups: 1-phosphoglycerol and O-acetyl groups in EPS-1 and a single O-acetyl group in EPS-2. Analysis of a deletion mutant (ΔepsE) lacking the putative priming glycosyltransferase gene located within a predicted eps gene cluster revealed that the mutant could produce EPS-1 but not EPS-2, indicating that epsE is essential for the biosynthesis of EPS-2. Atomic force microscopy confirmed the localization of galactose residues on the exterior of wild type cells and their absence in the ΔepsE mutant. EPS2 was found to adopt a random coil structural conformation. Deletion of the entire 14-kb eps cluster resulted in an acapsular mutant phenotype that was not able to produce either EPS-2 or EPS-1. Alterations in the cell surface properties of the EPS-specific mutants were demonstrated by differences in binding of an anti-wild type L. johnsonii antibody. These findings provide insights into the biosynthesis and structures of novel exopolysaccharides produced by L. johnsonii FI9785, which are likely to play an important role in biofilm formation, protection against harsh environment of the gut, and colonization of the host.
Karuga, Robinson Njoroge; Njenga, Serah Nduta; Mulwa, Rueben; Kilonzo, Nduku; Bahati, Prince; O'reilley, Kevin; Gelmon, Lawrence; Mbaabu, Stephen; Wachihi, Charles; Githuka, George; Kiragu, Michael
2016-01-01
The MSM population in Kenya contributes to 15% of HIV incidence. This calls for innovative HIV prevention interventions. Pre-exposure prophylaxis (PrEP) has been efficacious in preventing HIV among MSM in trials. There is limited data on the willingness to take daily oral PrEP in sub-Sahara Africa. PrEP has not been approved for routine use in most countries globally. This study aimed to document the willingness to take PrEP and barriers to uptake and adherence to PrEP in Kenya. The findings will inform the design of a PrEP delivery program as part of the routine HIV combination prevention. Eighty MSM were recruited in 2 Counties in December 2013. Quantitative data on sexual behaviour and willingness to take PrEP were collected using semi-structured interviews and analysed using SPSS. Qualitative data on knowledge of PrEP, motivators and barriers to uptake and adherence to PrEP were collected using in-depth interviews and FGDs and analysed using Nvivo. Analysis of data in willingness to take PrEP was conducted on the HIV negative participants (n = 55). 83% of MSM were willing to take daily oral HIV PrEP. Willingness to take PrEP was higher among the bi-sexual and younger men. Motivators for taking PrEP were the need to stay HIV negative and to protect their partners. History of poor medication adherence, fear of side effects and HIV stigma were identified as potential barriers to adherence. Participants were willing to buy PrEP at a subsidized price. There is willingness to take PrEP among MSM in Kenya and there is need to invest in targeted education and messaging on PrEP to enhance adherence, proper use and reduce stigma in the general population and among policy makers.
Saberi, Parya; Gamarel, Kristi E; Neilands, Torsten B; Comfort, Megan; Sheon, Nicolas; Darbes, Lynae A; Johnson, Mallory O
2012-01-01
We conducted a mixed-methods study to examine serodiscordant and seroconcordant (HIV-positive/HIV-positive) male couples' PrEP awareness, concerns regarding health care providers offering PrEP to the community, and correlates of PrEP uptake by the HIV-negative member of the couple. Qualitative sub-study included one-on-one interviews to gain a deeper understanding of participants' awareness of and experiences with PrEP and concerns regarding health care providers offering PrEP to men who have sex with men (MSM). Quantitative analyses consisted of a cross-sectional study in which participants were asked about the likelihood of PrEP uptake by the HIV-negative member of the couple and level of agreement with health care providers offering PrEP to anyone requesting it. We used multivariable regression to examine associations between PrEP questions and covariates of interest and employed an inductive approach to identify key qualitative themes. Among 328 men (164 couples), 62% had heard about PrEP, but approximately one-quarter were mistaking it with post-exposure prophylaxis. The majority of participants had low endorsement of PrEP uptake and 40% were uncertain if health care providers should offer PrEP to anyone requesting it. Qualitative interviews with 32 men suggest that this uncertainty likely stems from concerns regarding increased risk compensation. Likelihood of future PrEP uptake by the HIV-negative member of the couple was positively associated with unprotected insertive anal intercourse but negatively correlated with unprotected receptive anal intercourse. Findings suggest that those at greatest risk may not be receptive of PrEP. Those who engage in moderate risk express more interest in PrEP; however, many voice concerns of increased risk behavior in tandem with PrEP use. Results indicate a need for further education of MSM communities and the need to determine appropriate populations in which PrEP can have the highest impact.
Structure and Biosynthesis of Two Exopolysaccharides Produced by Lactobacillus johnsonii FI9785*
Dertli, Enes; Colquhoun, Ian J.; Gunning, A. Patrick; Bongaerts, Roy J.; Le Gall, Gwénaëlle; Bonev, Boyan B.; Mayer, Melinda J.; Narbad, Arjan
2013-01-01
Exopolysaccharides were isolated and purified from Lactobacillus johnsonii FI9785, which has previously been shown to act as a competitive exclusion agent to control Clostridium perfringens in poultry. Structural analysis by NMR spectroscopy revealed that L. johnsonii FI9785 can produce two types of exopolysaccharide: EPS-1 is a branched dextran with the unusual feature that every backbone residue is substituted with a 2-linked glucose unit, and EPS-2 was shown to have a repeating unit with the following structure: -6)-α-Glcp-(1–3)-β-Glcp-(1–5)-β-Galf-(1–6)-α-Glcp-(1–4)-β-Galp-(1–4)-β-Glcp-(1-. Sites on both polysaccharides were partially occupied by substituent groups: 1-phosphoglycerol and O-acetyl groups in EPS-1 and a single O-acetyl group in EPS-2. Analysis of a deletion mutant (ΔepsE) lacking the putative priming glycosyltransferase gene located within a predicted eps gene cluster revealed that the mutant could produce EPS-1 but not EPS-2, indicating that epsE is essential for the biosynthesis of EPS-2. Atomic force microscopy confirmed the localization of galactose residues on the exterior of wild type cells and their absence in the ΔepsE mutant. EPS2 was found to adopt a random coil structural conformation. Deletion of the entire 14-kb eps cluster resulted in an acapsular mutant phenotype that was not able to produce either EPS-2 or EPS-1. Alterations in the cell surface properties of the EPS-specific mutants were demonstrated by differences in binding of an anti-wild type L. johnsonii antibody. These findings provide insights into the biosynthesis and structures of novel exopolysaccharides produced by L. johnsonii FI9785, which are likely to play an important role in biofilm formation, protection against harsh environment of the gut, and colonization of the host. PMID:24019531
Critical error fields for locked mode instability in tokamaks
DOE Office of Scientific and Technical Information (OSTI.GOV)
La Haye, R.J.; Fitzpatrick, R.; Hender, T.C.
1992-07-01
Otherwise stable discharges can become nonlinearly unstable to disruptive locked modes when subjected to a resonant {ital m}=2, {ital n}=1 error field from irregular poloidal field coils, as in DIII-D (Nucl. Fusion {bold 31}, 875 (1991)), or from resonant magnetic perturbation coils as in COMPASS-C ({ital Proceedings} {ital of} {ital the} 18{ital th} {ital European} {ital Conference} {ital on} {ital Controlled} {ital Fusion} {ital and} {ital Plasma} {ital Physics}, Berlin (EPS, Petit-Lancy, Switzerland, 1991), Vol. 15C, Part II, p. 61). Experiments in Ohmically heated deuterium discharges with {ital q}{approx}3.5, {ital {bar n}} {approx} 2 {times} 10{sup 19} m{sup {minus}3} andmore » {ital B}{sub {ital T}} {approx} 1.2 T show that a much larger relative error field ({ital B}{sub {ital r}21}/{ital B}{sub {ital T}} {approx} 1 {times} 10{sup {minus}3}) is required to produce a locked mode in the small, rapidly rotating plasma of COMPASS-C ({ital R}{sub 0} = 0.56 m, {ital f}{approx}13 kHz) than in the medium-sized plasmas of DIII-D ({ital R}{sub 0} = 1.67 m, {ital f}{approx}1.6 kHz), where the critical relative error field is {ital B}{sub {ital r}21}/{ital B}{sub {ital T}} {approx} 2 {times} 10{sup {minus}4}. This dependence of the threshold for instability is explained by a nonlinear tearing theory of the interaction of resonant magnetic perturbations with rotating plasmas that predicts the critical error field scales as ({ital fR}{sub 0}/{ital B}{sub {ital T}}){sup 4/3}{ital {bar n}}{sup 2/3}. Extrapolating from existing devices, the predicted critical field for locked modes in Ohmic discharges on the International Thermonuclear Experimental Reactor (ITER) (Nucl. Fusion {bold 30}, 1183 (1990)) ({ital f}=0.17 kHz, {ital R}{sub 0} = 6.0 m, {ital B}{sub {ital T}} = 4.9 T, {ital {bar n}} = 2 {times} 10{sup 19} m{sup {minus}3}) is {ital B}{sub {ital r}21}/{ital B}{sub {ital T}} {approx} 2 {times} 10{sup {minus}5}.« less
Joshi, Nikita; Lira, Alena; Mehta, Ninfa; Paladino, Lorenzo; Sinert, Richard
2013-01-01
Understanding history, physical examination, and ultrasonography (US) to diagnose extremity fractures compared with radiography has potential benefits of decreasing radiation exposure, costs, and pain and improving emergency department (ED) resource management and triage time. The authors performed two electronic searches using PubMed and EMBASE databases for studies published between 1965 to 2012 using a strategy based on the inclusion of any patient presenting with extremity injuries suspicious for fracture who had history and physical examination and a separate search for US performed by an emergency physician (EP) with subsequent radiography. The primary outcome was operating characteristics of ED history, physical examination, and US in diagnosing radiologically proven extremity fractures. The methodologic quality of the studies was assessed using the quality assessment of studies of diagnostic accuracy tool (QUADAS-2). Nine studies met the inclusion criteria for history and physical examination, while eight studies met the inclusion criteria for US. There was significant heterogeneity in the studies that prevented data pooling. Data were organized into subgroups based on anatomic fracture locations, but heterogeneity within the subgroups also prevented data pooling. The prevalence of fracture varied among the studies from 22% to 70%. Upper extremity physical examination tests have positive likelihood ratios (LRs) ranging from 1.2 to infinity and negative LRs ranging from 0 to 0.8. US sensitivities varied between 85% and 100%, specificities varied between 73% and 100%, positive LRs varied between 3.2 and 56.1, and negative LRs varied between 0 and 0.2. Compared with radiography, EP US is an accurate diagnostic test to rule in or rule out extremity fractures. The diagnostic accuracy for history and physical examination are inconclusive. Future research is needed to understand the accuracy of ED US when combined with history and physical examination for upper and lower extremity fractures. © 2013 by the Society for Academic Emergency Medicine.
Selective neuronal entrainment to the beat and meter embedded in a musical rhythm.
Nozaradan, Sylvie; Peretz, Isabelle; Mouraux, André
2012-12-05
Fundamental to the experience of music, beat and meter perception refers to the perception of periodicities while listening to music occurring within the frequency range of musical tempo. Here, we explored the spontaneous building of beat and meter hypothesized to emerge from the selective entrainment of neuronal populations at beat and meter frequencies. The electroencephalogram (EEG) was recorded while human participants listened to rhythms consisting of short sounds alternating with silences to induce a spontaneous perception of beat and meter. We found that the rhythmic stimuli elicited multiple steady state-evoked potentials (SS-EPs) observed in the EEG spectrum at frequencies corresponding to the rhythmic pattern envelope. Most importantly, the amplitude of the SS-EPs obtained at beat and meter frequencies were selectively enhanced even though the acoustic energy was not necessarily predominant at these frequencies. Furthermore, accelerating the tempo of the rhythmic stimuli so as to move away from the range of frequencies at which beats are usually perceived impaired the selective enhancement of SS-EPs at these frequencies. The observation that beat- and meter-related SS-EPs are selectively enhanced at frequencies compatible with beat and meter perception indicates that these responses do not merely reflect the physical structure of the sound envelope but, instead, reflect the spontaneous emergence of an internal representation of beat, possibly through a mechanism of selective neuronal entrainment within a resonance frequency range. Taken together, these results suggest that musical rhythms constitute a unique context to gain insight on general mechanisms of entrainment, from the neuronal level to individual level.
beta-Endorphin-induced analgesia is inhibited by synthetic analogs of beta-endorphin.
Nicolas, P; Hammonds, R G; Li, C H
1984-05-01
Competitive antagonism of human beta-endorphin (beta h-EP)-induced analgesia by synthetic beta h-EP analogs with high in vitro opiate receptor binding to in vivo analgesic potency ratio has been demonstrated. A parallel shift of the dose-response curve for analgesia to the right was observed when either beta h-EP or [ Trp27 ] -beta h-EP was coinjected with various doses of [Gln8, Gly31 ]-beta h-EP-Gly-Gly-NH2, [Arg9,19,24,28,29]-beta h-EP, or [ Cys11 ,26, Phe27 , Gly31 ]-beta h-EP. It was estimated that the most potent antagonist, [Gln8, Gly31 ]-beta h-EP-Gly-NH2, is at least 200 times more potent than naloxone.
Sineath, R Craig; Finneran, Catherine; Sullivan, Patrick; Sanchez, Travis; Smith, Dawn K; Griensven, Frits van; Wimonsate, Wipas; Stephenson, Rob
2013-01-01
Little is known about HIV preexposure prophylaxis (PrEP) acceptability among men who have sex with men (MSM) in Thailand. The authors recruited an online convenience sample of Thai MSM (n = 404) to assess the knowledge of and interest in PrEP. Less than 7% had heard of PrEP; however, 35% indicated interest in PrEP after an explanation of its possible efficacy. Regression modeling demonstrated that HIV knowledge and risk behavior, but not demographics, are significant predictors of PrEP interest. More information and education about PrEP is necessary and more research is needed to examine PrEP acceptability and to inform the message for PrEP uptake.
Calabrese, Sarah K; Underhill, Kristen
2015-10-01
Antiretroviral preexposure prophylaxis (PrEP; emtricitabine and tenofovir disoproxil fumarate [Truvada]) prevents HIV without penalizing sexual pleasure, and may even enhance pleasure (e.g., by reducing HIV-related anxiety). However, concern about sexual risk behavior increasing with PrEP use (risk compensation) and corresponding stereotypes of promiscuity may undermine PrEP's preventive potential. In this commentary, we review literature on sexual behavior change accompanying PrEP use, discuss risk compensation concerns and the "Truvada whore" stereotype as PrEP barriers, question the appropriateness of restricting PrEP access because of risk compensation, and consider sexual pleasure as a benefit of PrEP, an acceptable motive for seeking PrEP, and a core element of health. It is essential for science to trump stereotypes and sex-negative messaging in guiding decision-making affecting PrEP access and uptake.