Science.gov

Sample records for activities included conducting

  1. Cryogenic regenerator including sarancarbon heat conduction matrix

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor); Petrick, S. Walter (Inventor); Britcliffe, Michael J. (Inventor)

    1989-01-01

    A saran carbon matrix is employed to conduct heat through the heat storing volume of a cryogenic regenerator. When helium is adsorbed into the saran carbon matrix, the combination exhibits a volumetric specific heat much higher than previously used lead balls. A helium adsorbed saran regenerator should allow much lower refrigerator temperatures than those practically obtainable with lead based regenerators for regenerator type refrigeration systems.

  2. Sugar beet activities of the USDA-ARS East Lansing conducted in cooperation with Saginaw Research & Extension Center during 2013 (including Project 905)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evaluation and rating plots were planted at the Saginaw Valley Research & Extension Center (SVREC) in Frankenmuth, MI in 2013 that focused on Cercospora leaf spot and Rhizoctonia seedling disease performance of a wide range of Beta vulgaris materials. Leaf spot trials were conducted in conjunction w...

  3. A model for including thermal conduction in molecular dynamics simulations

    NASA Technical Reports Server (NTRS)

    Wu, Yue; Friauf, Robert J.

    1989-01-01

    A technique is introduced for including thermal conduction in molecular dynamics simulations for solids. A model is developed to allow energy flow between the computational cell and the bulk of the solid when periodic boundary conditions cannot be used. Thermal conduction is achieved by scaling the velocities of atoms in a transitional boundary layer. The scaling factor is obtained from the thermal diffusivity, and the results show good agreement with the solution for a continuous medium at long times. The effects of different temperature and size of the system, and of variations in strength parameter, atomic mass, and thermal diffusivity were investigated. In all cases, no significant change in simulation results has been found.

  4. Planning and Conducting Research Activities.

    ERIC Educational Resources Information Center

    Christiansen, Richard L.

    1983-01-01

    Some directions and influences on dental research activities in the near future are discussed. Current challenges include international competition, fellowships, and equipment. Potential research activity includes preventive medicine, epidemiology, chronic illness, the elderly, bioengineering, materials research, nutrition, soft tissue research,…

  5. A study on Effective Thermal Conductivity of Packed Bed of Adsorbent Including Water

    NASA Astrophysics Data System (ADS)

    Hirasawa, Yoshio; Ohta, Ryuma; Takegoshi, Eisyun

    In the present study, an effective thermal conductivity of the packed bed of an adsorbent including water was measured experimentally by using the transient hot wire method in temperature range from about -40°C to room temperature. Zeolite particle and activated carbon particle were employed as the adsorbent. The water included in the adsorbent was classified to three kinds; namely, the adsorbed water in the adsorption site with a nanometer order in particle, the osmosis water existing in gap with lager size than the adsorption site and the free water around particle. The measurement was performed with changing the mass ratio of adsorbed water and osmosis water and was also performed for the particle filled by the free water. As the results, the effective thermal conductivity of the packed bed increased with the increase of temperature except the case containing free water. In zeolite, the effective thermal conductivity of the packed bed of particles with adsorbed water became bigger than that of the desorbed particle about 10% though the adsorbed water was trapped in the adsorption site as a single molecular in zeolite particle. In activated carbon, the effective thermal conductivity was larger than that of desorbed particle about 20%. Next, in the packed bed of particle with the osmosis water, the effective thermal conductivity indicated about two times of that of particle with the adsorbed water. In the packed bed of particle filled by free water, the effective thermal conductivity increased suddenly under 0°C. It is considered that the thermal conductivity of ice affected seriously to the effective thermal conductivity because ice was the continuous phase in the bed.

  6. Rabbit-Specific Ventricular Model of Cardiac Electrophysiological Function including Specialized Conduction System

    PubMed Central

    Bordas, R.; Gillow, K.; Lou, Q.; Efimov, I. R.; Gavaghan, D.; Kohl, P.; Grau, V.; Rodriguez, B.

    2011-01-01

    The function of the ventricular specialized conduction system in the heart is to ensure the coordinated electrical activation of the ventricles. It is therefore critical to the overall function of the heart, and has also been implicated as an important player in various diseases, including lethal ventricular arrhythmias such as ventricular fibrillation and drug-induced torsades de pointes. However, current ventricular models of electrophysiology usually ignore, or include highly simplified representations of the specialized conduction system. Here, we describe the development of a image-based, species-consistent, anatomically-detailed model of rabbit ventricular electrophysiology that incorporates a detailed description of the free-running part of the specialized conduction system. Techniques used for the construction of the geometrical model of the specialized conduction system from a magnetic resonance dataset and integration of the system model into a ventricular anatomical model, developed from the same dataset, are described. Computer simulations of rabbit ventricular electrophysiology are conducted using the novel anatomical model and rabbit-specific membrane kinetics to investigate the importance of the components and properties of the conduction system in determining ventricular function under physiological conditions. Simulation results are compared to panoramic optical mapping experiments for model validation and results interpretation. Full access is provided to the anatomical models developed in this study. PMID:21672547

  7. Active Bone Conduction Prosthesis: BonebridgeTM

    PubMed Central

    Zernotti, Mario E.; Sarasty, Andrea Bravo

    2015-01-01

    Introduction Bone conduction implants are indicated for patients with conductive and mixed hearing loss, as well as for patients with single-sided deafness (SSD). The transcutaneous technology avoids several complications of the percutaneous bone conduction implants including skin reaction, skin growth over the abutment, and wound infection. The Bonebridge (MED-EL, Austria) prosthesis is a semi-implantable hearing system: the BCI (Bone Conduction Implant) is the implantable part that contains the Bone Conduction-Floating Mass Transducer (BC-FMT), which applies the vibrations directly to the bone; the external component is the audio processor Amadé BB (MED-EL, Austria), which digitally processes the sound and sends the information through the coil to the internal part. Bonebridge may be implanted through three different approaches: the transmastoid, the retrosigmoid, or the middle fossa approach. Objective This systematic review aims to describe the world́s first active bone conduction implant system, Bonebridge, as well as describe the surgical techniques in the three possible approaches, showing results from implant centers in the world in terms of functional gain, speech reception thresholds and word recognition scores. Data Synthesis The authors searched the MEDLINE database using the key term Bonebridge. They selected only five publications to include in this systematic review. The review analyzes 20 patients that received Bonebridge implants with different approaches and pathologies. Conclusion Bonebridge is a solution for patients with conductive/mixed hearing loss and SSD with different surgical approaches, depending on their anatomy. The system imparts fewer complications than percutaneous bone conduction implants and shows proven benefits in speech discrimination and functional gain. PMID:26491482

  8. Active Bone Conduction Prosthesis: Bonebridge(TM).

    PubMed

    Zernotti, Mario E; Sarasty, Andrea Bravo

    2015-10-01

    Introduction Bone conduction implants are indicated for patients with conductive and mixed hearing loss, as well as for patients with single-sided deafness (SSD). The transcutaneous technology avoids several complications of the percutaneous bone conduction implants including skin reaction, skin growth over the abutment, and wound infection. The Bonebridge (MED-EL, Austria) prosthesis is a semi-implantable hearing system: the BCI (Bone Conduction Implant) is the implantable part that contains the Bone Conduction-Floating Mass Transducer (BC-FMT), which applies the vibrations directly to the bone; the external component is the audio processor Amadé BB (MED-EL, Austria), which digitally processes the sound and sends the information through the coil to the internal part. Bonebridge may be implanted through three different approaches: the transmastoid, the retrosigmoid, or the middle fossa approach. Objective This systematic review aims to describe the world́s first active bone conduction implant system, Bonebridge, as well as describe the surgical techniques in the three possible approaches, showing results from implant centers in the world in terms of functional gain, speech reception thresholds and word recognition scores. Data Synthesis The authors searched the MEDLINE database using the key term Bonebridge. They selected only five publications to include in this systematic review. The review analyzes 20 patients that received Bonebridge implants with different approaches and pathologies. Conclusion Bonebridge is a solution for patients with conductive/mixed hearing loss and SSD with different surgical approaches, depending on their anatomy. The system imparts fewer complications than percutaneous bone conduction implants and shows proven benefits in speech discrimination and functional gain.

  9. Guidance manual for conducting technology demonstration activities

    SciTech Connect

    Jolley, Robert L.; Morris, Michael I.; Singh, Suman P.N.

    1991-12-01

    This demonstration guidance manual has been prepared to assist Martin Marietta Energy Systems, Inc. (Energy Systems), staff in conducting demonstrations. It is prepared in checklist style to facilitate its use and assumes that Energy Systems personnel have project management responsibility. In addition to a detailed step-by-step listing of procedural considerations, a general checklist, logic flow diagram, and several examples of necessary plans are included to assist the user in developing an understanding of the many complex activities required to manage technology demonstrations. Demonstrations are pilot-scale applications of often innovative technologies to determine the commercial viability of the technologies to perform their designed function. Demonstrations are generally conducted on well-defined problems for which existing technologies or processes are less than satisfactory in terms of effectiveness, cost, and/or regulatory compliance. Critically important issues in demonstration management include, but are not limited to, such factors as communications with line and matrix management and with the US Department of Energy (DOE) and Energy Systems staff responsible for management oversight, budgetary and schedule requirements, regulatory compliance, and safety.

  10. SIMULATIONS OF MAGNETOHYDRODYNAMICS INSTABILITIES IN INTRACLUSTER MEDIUM INCLUDING ANISOTROPIC THERMAL CONDUCTION

    SciTech Connect

    Bogdanovic, Tamara; Reynolds, Christopher S.; Balbus, Steven A.; Parrish, Ian J. E-mail: chris@astro.umd.ed E-mail: iparrish@astro.berkeley.ed

    2009-10-10

    We perform a suite of simulations of cooling cores in clusters of galaxies in order to investigate the effect of the recently discovered heat flux buoyancy instability (HBI) on the evolution of cores. Our models follow the three-dimensional magnetohydrodynamics of cooling cluster cores and capture the effects of anisotropic heat conduction along the lines of magnetic field, but do not account for the cosmological setting of clusters or the presence of active galactic nuclei (AGNs). Our model clusters can be divided into three groups according to their final thermodynamical state: catastrophically collapsing cores, isothermal cores, and an intermediate group whose final state is determined by the initial configuration of magnetic field. Modeled cores that are reminiscent of real cluster cores show evolution toward thermal collapse on a timescale which is prolonged by a factor of approx2-10 compared with the zero-conduction cases. The principal effect of the HBI is to re-orient field lines to be perpendicular to the temperature gradient. Once the field has been wrapped up onto spherical surfaces surrounding the core, the core is insulated from further conductive heating (with the effective thermal conduction suppressed to less than 10{sup -2} of the Spitzer value) and proceeds to collapse. We speculate that, in real clusters, the central AGN and possibly mergers play the role of 'stirrers', periodically disrupting the azimuthal field structure and allowing thermal conduction to sporadically heat the core.

  11. [Bone Conduction and Active Middle Ear Implants].

    PubMed

    Volkenstein, S; Thomas, J P; Dazert, S

    2016-05-01

    The majority of patients with moderate to severe hearing loss can be supplied with conventional hearing aids depending on severity and cause for hearing loss in a satisfying way. However, some patients either do not benefit enough from conventional hearing aids or cannot wear them due to inflammatory reactions and chronic infections of the external auditory canal or due to anatomical reasons. For these patients there are fully- and semi-implantable middle ear and bone conduction implants available. These devices either directly stimulate the skull (bone conduction devices), middle ear structures (active middle ear implants) or the cochlea itself (direct acoustic stimulation). Patients who failed surgical hearing rehabilitation or do not benefit from conventional hearing aids may achieve a significant better speech understanding and tremendous improvement in quality of life by implantable hearing devices with careful attention to the audiological and anatomical indication criteria.

  12. A software platform for the comparative analysis of electroanatomic and imaging data including conduction velocity mapping.

    PubMed

    Cantwell, Chris D; Roney, Caroline H; Ali, Rheeda L; Qureshi, Norman A; Lim, Phang Boon; Peters, Nicholas S

    2014-01-01

    Electroanatomic mapping systems collect increasingly large quantities of spatially-distributed electrical data which may be potentially further scrutinized post-operatively to expose mechanistic properties which sustain and perpetuate atrial fibrillation. We describe a modular software platform, developed to post-process and rapidly analyse data exported from electroanatomic mapping systems using a range of existing and novel algorithms. Imaging data highlighting regions of scar can also be overlaid for comparison. In particular, we describe the conduction velocity (CV) mapping algorithm used to highlight wavefront behaviour. CV was found to be particularly sensitive to the spatial distribution of the triangulation points and corresponding activation times. A set of geometric conditions were devised for selecting suitable triangulations of the electrogram set for generating CV maps.

  13. Theoretical and Experimental Investigation of Heat Conduction in Air, Including Effects of Oxygen Dissociation

    NASA Technical Reports Server (NTRS)

    Hansen, C. Frederick; Early, Richard A.; Alzofon, Frederick E.; Witteborn, Fred C.

    1959-01-01

    Solutions are presented for the conduction of beat through a semi-infinite gas medium having a uniform initial temperature and a constant boundary temperature. The coefficients of thermal conductivity and diffusivity are treated as variables, and the solutions are extended to the case of air at temperatures where oxygen dissociation occurs. These solutions are used together with shock-tube measurements to evaluate the integral of thermal conductivity for air as a function of temperature.

  14. The evolution of interstellar clouds in a streaming hot plasma including heat conduction

    NASA Astrophysics Data System (ADS)

    Vieser, W.; Hensler, G.

    2007-09-01

    Context: The interstellar medium contains warm clouds that are embedded in a hot dilute gas produced by supernovae. Because both gas phases are in contact, an interface forms where mass and energy are exchanged. Whether heat conduction leads to evaporation of these clouds or whether condensation dominates has been analytically derived. Both phases behave differently dynamically so that their relative motion has to be taken into account. Aims: Real clouds in static conditions that experience saturated heat conduction are stabilized against evaporation if self-gravity and cooling play a role. Here, we investigte to what extent heat conduction can hamper the dynamical disruption of clouds embedded in a streaming hot plasma. Methods: To examine the evolution of giant molecular clouds in the stream of a hot plasma we performed two-dimensional hydrodynamical simulations that take full account of self-gravity, heating and cooling effects and heat conduction by electrons. We use the thermal conductivity of a fully ionized hydrogen plasma proposed by Spitzer and a saturated heat flux according to Cowie & McKee in regions where the mean free path of the electrons is large compared to the temperature scaleheight. Results: Significant structural and evolutionary differences occur between simulations with and without heat conduction. Dense clouds in pure dynamical models experience dynamical destruction by Kelvin-Helmholtz (KH) instability. In static models heat conduction leads to evaporation of such clouds. Heat conduction acting on clouds in a gas stream smooths out steep temperature and density gradients at the edge of the cloud because the conduction timescale is shorter than the cooling timescale. This diminishes the velocity gradient between the streaming plasma and the cloud, so that the timescale for the onset of KH instabilities increases, and the surface of the cloud becomes less susceptible to KH instabilities. The stabilisation effect of heat conduction against KH

  15. Everglades National Park Including Biscayne National Park. Activity Book.

    ERIC Educational Resources Information Center

    Ruehrwein, Dick

    Intended to help elementary school children learn about the resources of the Everglades and Biscayne National Parks, this activity book includes information, puzzles, games, and quizzes. The booklet deals with concepts related to: (1) the seasons; (2) fire ecology; (3) water; (4) fish; (5) mammals; (6) mosquitos; (7) birds; (8) venomous snakes;…

  16. A Model for Hydrogen Thermal Conductivity and Viscosity Including the Critical Point

    NASA Technical Reports Server (NTRS)

    Wagner, Howard A.; Tunc, Gokturk; Bayazitoglu, Yildiz

    2001-01-01

    In order to conduct a thermal analysis of heat transfer to liquid hydrogen near the critical point, an accurate understanding of the thermal transport properties is required. A review of the available literature on hydrogen transport properties identified a lack of useful equations to predict the thermal conductivity and viscosity of liquid hydrogen. The tables published by the National Bureau of Standards were used to perform a series of curve fits to generate the needed correlation equations. These equations give the thermal conductivity and viscosity of hydrogen below 100 K. They agree with the published NBS tables, with less than a 1.5 percent error for temperatures below 100 K and pressures from the triple point to 1000 KPa. These equations also capture the divergence in the thermal conductivity at the critical point

  17. A New Finite-Conductivity Droplet Evaporation Model Including Liquid Turbulence Effect

    NASA Technical Reports Server (NTRS)

    Balasubramanyam, M. S.; Chen, C. P.; Trinh, H. P.

    2006-01-01

    A new approach to account for finite thermal conductivity and turbulence effects within atomizing droplets of an evaporating spray is presented in this paper. The model is an extension of the T-blob and T-TAB atomization/spray model of Trinh and Chen [9]. This finite conductivity model is based on the two-temperature film theory in which the turbulence characteristics of the droplet are used to estimate the effective thermal diffusivity for the liquid-side film thickness. Both one-way and two-way coupled calculations were performed to investigate the performance cf this model against the published experimental data.

  18. The Effects of Including a Callous-Unemotional Specifier for the Diagnosis of Conduct Disorder

    ERIC Educational Resources Information Center

    Kahn, Rachel E.; Frick, Paul J.; Youngstrom, Eric; Findling, Robert L.; Youngstrom, Jennifer Kogos

    2012-01-01

    Background: "With Significant Callous-Unemotional Traits" has been proposed as a specifier for conduct disorder (CD) in the upcoming revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V). The impact of this specifier on children diagnosed with CD should be considered. Methods: A multi-site cross-sectional design with…

  19. Blood lactate concentration after exposure to conducted energy weapons (including TASER® devices): is it clinically relevant?

    PubMed

    Jauchem, James R

    2013-09-01

    In previous studies, blood lactate concentration (BLac) consistently increased in anesthetized animals and in human subjects after exposures to TASER(®) conducted energy weapons (CEWs). Some have suggested the increased BLac would have detrimental consequences. In the current review, the following are evaluated: (a) the nature of muscle contractions due to CEWs, (b) general aspects of increased BLac, (c) previous studies of conventional neuromuscular electrical stimulation and CEW exposures, and (d) BLac in disease states. On the basis of these analyses, one can conclude that BLac, per se (independent of acidemia), would not be clinically relevant immediately after short-duration CEW applications, due to the short time course of any increase.

  20. Exposures to conducted electrical weapons (including TASER® devices): how many and for how long are acceptable?

    PubMed

    Jauchem, James R

    2015-01-01

    TASER(®) conducted electrical weapons (CEWs) are an important law-enforcement tool. The purposes of this study are a) to review recent literature regarding potential pathophysiological responses to applications of CEWs, and other related issues and b) to evaluate whether enough data exist to determine the acceptability of longer-duration (or repeated) exposures. This is a narrative review, using a multidisciplinary approach of analyzing reports from physiological, legal-medical, and police-strategy literature sources. In general, short-duration exposures to CEWs result in limited effects. Longer-duration or repeated exposures may be utilized with caution, although there are currently not enough data to determine the acceptability of all types of exposures. Data examined in the literature have inherent limitations. Appropriateness of specific types of CEW usage may be determined by individual police agencies, applying risk/benefit analyses unique to each organization. While more research is recommended, initial concepts of potential future long-duration or repeated CEW applications are presented.

  1. 40 CFR 725.238 - Activities conducted outside a structure.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Exemptions for Research and Development Activities § 725.238 Activities conducted outside a structure. (a) Exemption. (1) Research and development activities involving intentional testing in the environment...

  2. 25 CFR 900.196 - Do covered services include the conduct of clinical studies and investigations and the provision...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... studies and investigations and the provision of emergency services, including the operation of emergency motor vehicles? 900.196 Section 900.196 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR... Claims § 900.196 Do covered services include the conduct of clinical studies and investigations and...

  3. 25 CFR 900.196 - Do covered services include the conduct of clinical studies and investigations and the provision...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... studies and investigations and the provision of emergency services, including the operation of emergency motor vehicles? 900.196 Section 900.196 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR... Claims § 900.196 Do covered services include the conduct of clinical studies and investigations and...

  4. 25 CFR 900.196 - Do covered services include the conduct of clinical studies and investigations and the provision...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... studies and investigations and the provision of emergency services, including the operation of emergency motor vehicles? 900.196 Section 900.196 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR... Claims § 900.196 Do covered services include the conduct of clinical studies and investigations and...

  5. 25 CFR 900.196 - Do covered services include the conduct of clinical studies and investigations and the provision...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... studies and investigations and the provision of emergency services, including the operation of emergency motor vehicles? 900.196 Section 900.196 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR... Claims § 900.196 Do covered services include the conduct of clinical studies and investigations and...

  6. 25 CFR 900.196 - Do covered services include the conduct of clinical studies and investigations and the provision...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... studies and investigations and the provision of emergency services, including the operation of emergency motor vehicles? 900.196 Section 900.196 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR... Claims § 900.196 Do covered services include the conduct of clinical studies and investigations and...

  7. Synthesis of conducting polymer nanospheres of high electrochemical activity.

    PubMed

    Kłucińska, Katarzyna; Jaworska, Ewa; Gryczan, Piotr; Maksymiuk, Krzysztof; Michalska, Agata

    2015-08-14

    We propose a novel approach to obtain conducting polymer nanoparticles with high electrochemical activity and a narrow size distribution. The method - templateless and seedless - uses polyacrylate microspheres to deliver the monomer for the polymerization reaction. Thus the obtained nanostructures have an active - unblocked - surface allowing fast charge/ion-exchange and the formation of stable suspensions in water. The obtained nanostructures have the potential to be applied in different fields ranging from conductive coatings and additives for increasing electronic conductivity, to electrochemical sensors.

  8. Infrared transparent conductive coatings deposited by activated reactive evaporation

    NASA Astrophysics Data System (ADS)

    Marcovitch, Orna; Zipin, Hedva; Klein, Zeev; Lubezky, Iftah

    1991-04-01

    Infrared transparent conductive coatings were developed for ZnS substrates. The conductive layer was an indium oxide film deposited in a reactive atmosphere consisting of low energy oxygen ions. Activation of the gas molecules was performed by an ion source of the hollow cathode type. The deposited films were characterized by their transparency, conductivity and environmental durability. It was found that the positioning of the ion source relative to the substrates was critical for the film properties. High transmission and low sheet resistance of the film were obtained by optimization of the evaporation parameters which included oxygen pressure, cathode current, deposition rate, film thickness and substrate temperature. Application of the conductive film for both 3-5jim and 8-12im infrared atmospheric windows was possible. The transmission of the indium oxide film depend on the infrared free carriers absorption and the reflections at the substrate and air interfaces. Improvement of the optical performance was accomplished by depositing antireflective and induced transmission dielectric stacks. Several dielectric stacks were designed and matched to indium oxide layers of 50Q/sq and 30Q/sq sheet resistance for maximum transmission, either at a single wavelength or for a wide band in the 3-5pm and 8-11.5pm spectral regions. Typical average transmittance values of ZnS substrates coated with conductive stacks were 82% and 7L% in the 3-5pm region and 77% and 63% in the 8-'l2pm region for sheet resistances of 50Q/sq and 30Q/sq, respectively. At 1O.5pm peak transmittance values higher than 80% were obtained. The coatings were durable and passed adhesion, humidity and moderate abrasion tests in accordance with MIL-C--675C.

  9. Hypoosmotic stimuli activate a chloride conductance in rat taste cells.

    PubMed

    Gilbertson, Timothy A

    2002-05-01

    The oral cavity is subjected to a wide range of osmotic conditions, yet little is known about how solution osmolarity affects performance of the gustatory system. In order to elucidate the mechanism by which hypoosmotic stimuli affect the peripheral taste system, I have attempted to characterize the effects of hypoosmotic stimuli on individual rat taste receptor cells (TRCs) using whole-cell patch clamp recording. Currents elicited in response to voltage ramps (-90 to +60 mV) were recorded in control saline and in solutions varying only in osmolarity (-30, -60 and -90 mOsm). In roughly two-thirds of cells, hypoosmotic solutions (230 mOsm) caused a 15% increase in cell capacitance and activated a reversible conductance that exhibited marked adaptation in the continued presence of the stimulus. Similar responses could be elicited in taste cells from taste buds in the foliate and vallate papillae, the soft palate, the nasopharynx and the epiglottis. Ion substitution experiments were consistent with the interpretation that the predominant ion carried through these apparent volume- or stretch-activated channels was Cl(-) under normal conditions. Reversal potentials for the hypoosmotic-induced current closely matched those predicted by the Goldman-Hodgkin-Katz constant field equation for a Cl(-) conductance. The relative permeability sequence of the hypoosmotic-activated current in TRCs was thiocyanate(-) > or = l(-) > or = Br(-) > Cl(-) > or = F(-) > or = isethionate(-) > gluconate(-). Pharmacological experiments revealed that this Cl(-) conductance was inhibited by 4,4'-diisothiocyanatostilbene-2, 2'-disulfonic acid and 5-nitro-3-(3-phenyl-propylamino)benzoic acid (EC(50) = 1.3 and 4.6 microM, respectively), but not by CdCl(2) (300 microM) nor GdCl(3) (200 microM). I hypothesize that this hypoosmotic-activated Cl(-) conductance, which is similar to the well-characterized swelling-activated Cl(-) current, may contribute to volume regulation and could represent the

  10. Opposing Effects of Intrinsic Conductance and Correlated Synaptic Input on Vm-Fluctuations during Network Activity

    PubMed Central

    Kolind, Jens; Hounsgaard, Jørn; Berg, Rune W.

    2012-01-01

    Neurons often receive massive concurrent bombardment of synaptic inhibition and excitation during functional network activity. This increases membrane conductance and causes fluctuations in membrane potential (Vm) and spike timing. The conductance increase is commonly attributed to synaptic conductance, but also includes the intrinsic conductances recruited during network activity. These two sources of conductance have contrasting dynamic properties at sub-threshold membrane potentials. Synaptic transmitter gated conductance changes abruptly and briefly with each presynaptic action potential. If the spikes arrive at random times the changes in synaptic conductance are therefore stochastic and rapid during intense network activity. In comparison, sub-threshold intrinsic conductances vary smoothly in time. In the present study this discrepancy is investigated using two conductance-based models: a (1) compartment model and a (2) compartment with realistic slow intrinsic conductances. We examine the effects of varying the relative contributions of non-fluctuating intrinsic conductance with fluctuating concurrent inhibitory and excitatory synaptic conductance. For given levels of correlation in the synaptic input we find that the magnitude of the membrane fluctuations uniquely determines the relative contribution of synaptic and intrinsic conductance. We also quantify how Vm-fluctuations vary with synaptic correlations for fixed ratios of synaptic and intrinsic conductance. Interestingly, the levels of Vm -fluctuations and conductance observed experimentally during functional network activity leave little room for intrinsic conductance to contribute. Even without intrinsic conductances the variance in Vm -fluctuations can only be explained by a high degree of correlated firing among presynaptic neurons. PMID:22783184

  11. Antiradical activity of gallic acid included in lipid interphases.

    PubMed

    Salcedo, C L; Frías, M A; Cutro, A C; Nazareno, M A; Disalvo, E A

    2014-10-01

    Polyphenols are well known as antioxidant agents and by their effects on the hydration layers of lipid interphases. Among them, gallic acid and its derivatives are able to decrease the dipole potential and to act in water as a strong antioxidant. In this work we have studied both effects on lipid interphases in monolayers and bilayers of dimyristoylphosphatidylcholine. The results show that gallic acid (GA) increases the negative surface charges of large unilamellar vesicles (LUVs) and decreases the dipole potential of the lipid interphase. As a result, positively charged radical species such as ABTS(+) are able to penetrate the membrane forming an association with GA. These results allow discussing the antiradical activity (ARA) of GA at the membrane phase which may be taking place in water spaces between the lipids.

  12. In vivo biocompatibility of boron doped and nitrogen included conductive-diamond for use in medical implants.

    PubMed

    Garrett, David J; Saunders, Alexia L; McGowan, Ceara; Specks, Joscha; Ganesan, Kumaravelu; Meffin, Hamish; Williams, Richard A; Nayagam, David A X

    2016-01-01

    Recently, there has been interest in investigating diamond as a material for use in biomedical implants. Diamond can be rendered electrically conducting by doping with boron or nitrogen. This has led to inclusion of boron doped and nitrogen included diamond elements as electrodes and/or feedthroughs for medical implants. As these conductive device elements are not encapsulated, there is a need to establish their clinical safety for use in implants. This article compares the biocompatibility of electrically conducting boron doped diamond (BDD) and nitrogen included diamond films and electrically insulating poly crystalline diamond films against a silicone negative control and a BDD sample treated with stannous octoate as a positive control. Samples were surgically implanted into the back muscle of a guinea pig for a period of 4-15 weeks, excised and the implant site sectioned and submitted for histological analysis. All forms of diamond exhibited a similar or lower thickness of fibrotic tissue encapsulating compared to the silicone negative control samples. All forms of diamond exhibited similar or lower levels of acute, chronic inflammatory, and foreign body responses compared to the silicone negative control indicating that the materials are well tolerated in vivo.

  13. In vivo biocompatibility of boron doped and nitrogen included conductive-diamond for use in medical implants.

    PubMed

    Garrett, David J; Saunders, Alexia L; McGowan, Ceara; Specks, Joscha; Ganesan, Kumaravelu; Meffin, Hamish; Williams, Richard A; Nayagam, David A X

    2016-01-01

    Recently, there has been interest in investigating diamond as a material for use in biomedical implants. Diamond can be rendered electrically conducting by doping with boron or nitrogen. This has led to inclusion of boron doped and nitrogen included diamond elements as electrodes and/or feedthroughs for medical implants. As these conductive device elements are not encapsulated, there is a need to establish their clinical safety for use in implants. This article compares the biocompatibility of electrically conducting boron doped diamond (BDD) and nitrogen included diamond films and electrically insulating poly crystalline diamond films against a silicone negative control and a BDD sample treated with stannous octoate as a positive control. Samples were surgically implanted into the back muscle of a guinea pig for a period of 4-15 weeks, excised and the implant site sectioned and submitted for histological analysis. All forms of diamond exhibited a similar or lower thickness of fibrotic tissue encapsulating compared to the silicone negative control samples. All forms of diamond exhibited similar or lower levels of acute, chronic inflammatory, and foreign body responses compared to the silicone negative control indicating that the materials are well tolerated in vivo. PMID:25611731

  14. 40 CFR 725.234 - Activities conducted inside a structure.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... intentional testing of a microorganism outside of a structure, as structure is defined in § 725.3. (d... structure. 725.234 Section 725.234 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... for Research and Development Activities § 725.234 Activities conducted inside a structure. A...

  15. 40 CFR 725.238 - Activities conducted outside a structure.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... structure. 725.238 Section 725.238 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... for Research and Development Activities § 725.238 Activities conducted outside a structure. (a... qualified individual, as defined in § 725.3. (b) Certification. To be eligible for the exemption under...

  16. 40 CFR 725.234 - Activities conducted inside a structure.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Exemptions for Research and Development Activities § 725.234 Activities conducted inside a structure. A person who manufactures, imports, or processes a microorganism is not subject to the reporting...

  17. Active subthreshold dendritic conductances shape the local field potential

    PubMed Central

    Ness, Torbjørn V.; Remme, Michiel W. H.

    2016-01-01

    Key points The local field potential (LFP), the low‐frequency part of extracellular potentials recorded in neural tissue, is often used for probing neural circuit activity. Interpreting the LFP signal is difficult, however.While the cortical LFP is thought mainly to reflect synaptic inputs onto pyramidal neurons, little is known about the role of the various subthreshold active conductances in shaping the LFP.By means of biophysical modelling we obtain a comprehensive qualitative understanding of how the LFP generated by a single pyramidal neuron depends on the type and spatial distribution of active subthreshold currents.For pyramidal neurons, the h‐type channels probably play a key role and can cause a distinct resonance in the LFP power spectrum.Our results show that the LFP signal can give information about the active properties of neurons and imply that preferred frequencies in the LFP can result from those cellular properties instead of, for example, network dynamics. Abstract The main contribution to the local field potential (LFP) is thought to stem from synaptic input to neurons and the ensuing subthreshold dendritic processing. The role of active dendritic conductances in shaping the LFP has received little attention, even though such ion channels are known to affect the subthreshold neuron dynamics. Here we used a modelling approach to investigate the effects of subthreshold dendritic conductances on the LFP. Using a biophysically detailed, experimentally constrained model of a cortical pyramidal neuron, we identified conditions under which subthreshold active conductances are a major factor in shaping the LFP. We found that, in particular, the hyperpolarization‐activated inward current, I h, can have a sizable effect and cause a resonance in the LFP power spectral density. To get a general, qualitative understanding of how any subthreshold active dendritic conductance and its cellular distribution can affect the LFP, we next performed a systematic

  18. Temperature dependence of dc electrical conductivity of activated carbon-metal oxide nanocomposites. Some insight into conduction mechanisms

    NASA Astrophysics Data System (ADS)

    Barroso-Bogeat, Adrián; Alexandre-Franco, María; Fernández-González, Carmen; Sánchez-González, José; Gómez-Serrano, Vicente

    2015-12-01

    From a commercial activated carbon (AC) and six metal oxide (Al2O3, Fe2O3, SnO2, TiO2, WO3 and ZnO) precursors, two series of AC-metal oxide nanocomposites are prepared by wet impregnation, oven-drying at 120 °C, and subsequent heat treatment at 200 or 850 °C in inert atmosphere. The temperature-dependent dc electrical conductivity of AC and the as-prepared nanocomposites is measured from room temperature up to ca. 200 °C in air atmosphere by the four-probe method. The decrease in conductivity for the hybrid materials as compared to AC is the result of a complex interplay between several factors, including not only the intrinsic conductivity, crystallite size, content and chemical nature of the supported nanoparticles, which ultimately depend on the precursor and heat treatment temperature, but also the adsorption of oxygen and water from the surrounding atmosphere. The conductivity data are discussed in terms of a thermally activated process. In this regard, both AC and the prepared nanocomposites behave as semiconductors, and the temperature-dependent conductivity data have been interpreted on the basis of the classical model proposed by Mott and Davis. Because of its high content of heteroatoms, AC may be considered as a heavily doped semiconductor, so that conduction of thermally excited carriers via acceptor or donor levels is expected to be the dominant mechanism. The activation energies for the hybrid materials suggest that the supported metal oxide nanoparticles strongly modify the electronic band structure of AC by introducing new trap levels in different positions along its band gap. Furthermore, the thermally activated conduction process satisfies the Meyer-Neldel rule, which is likely connected with the shift of the Fermi level due to the introduction of the different metal oxide nanoparticles in the AC matrix.

  19. Optimal design of active and semi-active suspensions including time delays and preview

    NASA Astrophysics Data System (ADS)

    Hac', A.; Youn, I.

    1993-10-01

    Several control laws for active and semi-active suspension based on a linear half car model are derived and investigated. The strategies proposed take full advantage of the fact that the road input to the rear wheels is a delayed version of that to the front wheels, which in turn can be obtained either from the measurements of the front wheels and body motions or by direct preview of road irregularities if preview sensors are available. The suspension systems are optimized with respect to ride comfort, road holding and suspension rattle space as expressed by the mean-square-values of body acceleration (including effects of heave and pitch), tire deflections and front and rear suspension travels. The optimal control laws that minimize the given performance index and include passivity constraints in the semi-active case are derived using calculus of variation. The optimal semi-active suspension becomes piecewise linear, varying between passive and fully active systems and combinations of them. The performances of active and semi-active systems with and without preview were evaluated by numerical simulation in the time and frequency domains. The results show that incorporation of time delay between the front and rear axles in controller design improves the dynamic behavior of the rear axle and control of body pitch motion, while additional preview improves front wheel dynamics and body heave.

  20. Conducting polymers as active materials in electrochemical capacitors

    NASA Astrophysics Data System (ADS)

    Rudge, Andy; Davey, John; Raistrick, Ian; Gottesfeld, Shimshon; Ferraris, John P.

    Electronically conducting polymer represent an interesting clas of materials for use in electrochemical capacitors thanks to the combination of high capacitive energy density and low materials cost. Three generalized typed of electrochemical capacitors can be constructed using conducting polymers as active material, and in the third of these, which utilized conducting polymers that can be both n- and p-doped, energy densities of up to 39 Wh per kg of active material on both electrodes have been demonstrated. This energy density is obtained using poly-3-(4-fluorophenyl)-thiophene (PEPT) in an electrolyte of 1 M tetramethylammonium trifluoromethanesulfonate (TMATFMS) in acetonitrile. This unique system exhibits reversible n- and p-doping to high charge density in relatively thich films of the active polymer and a cell voltage exceeding 3 V in the fully charged state. Impedance data for both n- and p-doped PFPT suggest that high power densities can be obtained in electrochemical capacitors based on this active conducting polymer.

  1. Analysis of magnetic probe signals including effect of cylindrical conducting wall for field-reversed configuration experiment

    SciTech Connect

    Ikeyama, Taeko; Hiroi, Masanori; Nemoto, Yuuichi; Nogi, Yasuyuki

    2008-06-15

    A confinement field is disturbed by magnetohydrodynamic (MHD) motions of a field-reversed configuration (FRC) plasma in a cylindrical conductor. The effect of the conductor should be included to obtain a spatial structure of the disturbed field with a good precision. For this purpose, a toroidal current in the plasma and an eddy current on a conducting wall are replaced by magnetic dipole and image magnetic dipole moments, respectively. Typical spatial structures of the disturbed field are calculated by using the dipole moments for such MHD motions as radial shift, internal tilt, external tilt, and n=2 mode deformation. Then, analytic formulas for estimating the shift distance, tilt angle, and deformation rate of the MHD motions from magnetic probe signals are derived. It is estimated from the calculations by using the dipole moments that the analytic formulas include an approximately 40% error. Two kinds of experiment are carried out to investigate the reliability of the calculations. First, a magnetic field produced by a circular current is measured in an aluminum pipe to confirm the replacement of the eddy current with the image magnetic dipole moments. The measured fields coincide well with the calculated values including the image magnetic dipole moments. Second, magnetic probe signals measured from the FRC plasma are substituted into the analytic formulas to obtain shift distance and deformation rate. The experimental results are compared to the MHD motions measured by using a radiation from the plasma. If the error included in the analytic formulas and the difference between the magnetic and optical structures in the plasma are considered, the results of the radiation measurement support well those of the magnetic analysis.

  2. Hierarchical nanostructured conducting polymer hydrogel with high electrochemical activity

    PubMed Central

    Pan, Lijia; Yu, Guihua; Zhai, Dongyuan; Lee, Hye Ryoung; Zhao, Wenting; Liu, Nian; Wang, Huiliang; Tee, Benjamin C.-K.; Shi, Yi; Cui, Yi; Bao, Zhenan

    2012-01-01

    Conducting polymer hydrogels represent a unique class of materials that synergizes the advantageous features of hydrogels and organic conductors and have been used in many applications such as bioelectronics and energy storage devices. They are often synthesized by polymerizing conductive polymer monomer within a nonconducting hydrogel matrix, resulting in deterioration of their electrical properties. Here, we report a scalable and versatile synthesis of multifunctional polyaniline (PAni) hydrogel with excellent electronic conductivity and electrochemical properties. With high surface area and three-dimensional porous nanostructures, the PAni hydrogels demonstrated potential as high-performance supercapacitor electrodes with high specific capacitance (∼480 F·g-1), unprecedented rate capability, and cycling stability (∼83% capacitance retention after 10,000 cycles). The PAni hydrogels can also function as the active component of glucose oxidase sensors with fast response time (∼0.3 s) and superior sensitivity (∼16.7 μA·mM-1). The scalable synthesis and excellent electrode performance of the PAni hydrogel make it an attractive candidate for bioelectronics and future-generation energy storage electrodes. PMID:22645374

  3. Effects of Leisure Education Programme Including Sportive Activities on Perceived Freedom in Leisure of Adolescents with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Ertuzun, Ezgi

    2015-01-01

    The objective of this experimental study is to determine the effect of leisure education programme including sportive activities on the perceived freedom in leisure of adolescents with mild intellectual disabilities. The research was designed with an experimental group (n = 37) and a control group (n = 34), and was conducted among a total of 71…

  4. Transparent electrical conducting films by activated reactive evaporation

    DOEpatents

    Bunshah, R.; Nath, P.

    1982-06-22

    Process and apparatus for producing transparent electrical conducting thin films by activated reactive evaporation is disclosed. Thin films of low melting point metals and alloys, such as indium oxide and indium oxide doped with tin, are produced by physical vapor deposition. The metal or alloy is vaporized by electrical resistance heating in a vacuum chamber, oxygen and an inert gas such as argon are introduced into the chamber, and vapor and gas are ionized by a beam of low energy electrons in a reaction zone between the resistance heater and the substrate. There is a reaction between the ionized oxygen and the metal vapor resulting in the metal oxide which deposits on the substrate as a thin film which is ready for use without requiring post deposition heat treatment. 1 fig.

  5. Transparent electrical conducting films by activated reactive evaporation

    DOEpatents

    Bunshah, Rointan; Nath, Prem

    1982-01-01

    Process and apparatus for producing transparent electrical conducting thin films by activated reactive evaporation. Thin films of low melting point metals and alloys, such as indium oxide and indium oxide doped with tin, are produced by physical vapor deposition. The metal or alloy is vaporized by electrical resistance heating in a vacuum chamber, oxygen and an inert gas such as argon are introduced into the chamber, and vapor and gas are ionized by a beam of low energy electrons in a reaction zone between the resistance heater and the substrate. There is a reaction between the ionized oxygen and the metal vapor resulting in the metal oxide which deposits on the substrate as a thin film which is ready for use without requiring post deposition heat treatment.

  6. Implications of Special Regions to Conducting Human Activities on Mars

    NASA Astrophysics Data System (ADS)

    Rummel, J. D.; Barlow, N. G.; Beaty, D. W.; Jones, M. A.; Hipkin, V.

    2014-12-01

    A MEPAG Science Analysis Group (SAG) has undertaken an analysis of Special Regions (SR) on Mars—regions where indigenous martian life could exist or where Earth microbes, if introduced, could survive and reproduce. The SR-SAG has considered the impact of SR on future human activities on the martian surface. Human exploration requires access to in-situ resources, some of which may be found in SR. Water and oxygen for ISRU are found in the atmosphere, surface/near-surface ice, hydrated minerals, and perchlorates. Water ice is most abundant at latitudes poleward of ~60 degrees, but polar darkness, cold temperatures, and CO2 degassing present hazards to human operations in these regions. Accessible water is more limited toward the equator, though temperature and solar energy conditions become more favorable. The possible presence of liquid water in Recurring Slope Lineae and active gullies leads to their treatment as SR. Fuel for surface operations and propellants for crew ascent could be manufactured from the martian atmosphere and surface materials, but dust in the atmosphere may clog ISRU equipment and perchlorate is toxic to humans. Power may be produced from solar or nuclear energy. Reliance on solar energy limits operations to the equatorial zone where easily accessible ice resources are limited. Nuclear power allows surface operations at a range of latitudes, but waste heat could convert some non-SR into SR. Radiation shielding is necessary for long-term human operations on Mars and could be obtained by deposition of regolith or by water storage in tanks or as ice around habitats, or the use of underground habitats. SR-SAG recognizes that it will be impossible for all human-associated processes and operations to be conducted within entirely closed systems. Protocols need to be established so (1) human missions to Mars will not contaminate SR nor be contaminated by materials from them, and (2) human activities on Mars will avoid converting areas into SR.

  7. Redox-active charge carriers of conducting polymers as a tuner of conductivity and its potential window.

    PubMed

    Park, Han-Saem; Ko, Seo-Jin; Park, Jeong-Seok; Kim, Jin Young; Song, Hyun-Kon

    2013-01-01

    Electric conductivity of conducting polymers has been steadily enhanced towards a level worthy of being called its alias, "synthetic metal". PEDOT:PSS (poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate)), as a representative conducting polymer, recently reached around 3,000 S cm(-1), the value to open the possibility to replace transparent conductive oxides. The leading strategy to drive the conductivity increase is solvent annealing in which aqueous solution of PEDOT:PSS is treated with an assistant solvent such as DMSO (dimethyl sulfoxide). In addition to the conductivity enhancement, we found that the potential range in which PEDOT:PSS is conductive is tuned wider into a negative potential direction by the DMSO-annealing. Also, the increase in a redox-active fraction of charge carriers is proposed to be responsible for the enhancement of conductivity in the solvent annealing process. PMID:23949091

  8. Redox-active charge carriers of conducting polymers as a tuner of conductivity and its potential window

    PubMed Central

    Park, Han-Saem; Ko, Seo-Jin; Park, Jeong-Seok; Kim, Jin Young; Song, Hyun-Kon

    2013-01-01

    Electric conductivity of conducting polymers has been steadily enhanced towards a level worthy of being called its alias, “synthetic metal”. PEDOT:PSS (poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate)), as a representative conducting polymer, recently reached around 3,000 S cm−1, the value to open the possibility to replace transparent conductive oxides. The leading strategy to drive the conductivity increase is solvent annealing in which aqueous solution of PEDOT:PSS is treated with an assistant solvent such as DMSO (dimethyl sulfoxide). In addition to the conductivity enhancement, we found that the potential range in which PEDOT:PSS is conductive is tuned wider into a negative potential direction by the DMSO-annealing. Also, the increase in a redox-active fraction of charge carriers is proposed to be responsible for the enhancement of conductivity in the solvent annealing process. PMID:23949091

  9. Small Conductance Ca2+-Activated K+ Channels and Cardiac Arrhythmias

    PubMed Central

    Zhang, Xiao-Dong; Lieu, Deborah K.; Chiamvimonvat, Nipavan

    2015-01-01

    Small conductance Ca2+-activated K+ (SK, KCa2) channels are unique in that they are gated solely by changes in intracellular Ca2+ and hence, function to integrate intracellular Ca2+ and membrane potentials on a beat-to-beat basis. Recent studies have provided evidence for the existence and functional significance of SK channels in the heart. Indeed, our knowledge of cardiac SK channels has been greatly expanded over the past decade. Interests in cardiac SK channels are further driven by recent studies suggesting the critical roles of SK channels in human atrial fibrillation, SK channel as a possible novel therapeutic target in atrial arrhythmias and up-regulation of SK channels in heart failure (HF) in animal models and human HF. However, there remain critical gaps in our knowledge. Specifically, blockade of SK channels in cardiac arrhythmias has been shown to be both anti-arrhythmic and proarrhythmic. This contemporary review will provide an overview of the literature on the role of cardiac SK channels in cardiac arrhythmias and to serve as a discussion platform for the current clinical perspectives. At the translational level, development of SK channel blockers as a new therapeutic target in the treatment of atrial fibrillation and the possible pro-arrhythmic effects merit further considerations and investigations. PMID:25956967

  10. 43 CFR 404.20 - What information must I include in my full proposal to conduct an appraisal or a feasibility study?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR RECLAMATION RURAL WATER SUPPLY PROGRAM Overview § 404.20 What information must I include in my full proposal to conduct...

  11. DEPTH CONTINUOUS HYDRAULIC CONDUCTIVITY PROFILING USING AN ACTIVE SOURCE PENETROMETER

    NASA Astrophysics Data System (ADS)

    Fitzgerald, M.; Elsworth, D.

    2009-12-01

    A method is developed to recover depth-continuous hydraulic conductivity profiles of an unconsolidated saturated aquifer using an active source penetrometer, the Hydraulic Profiling Tool (HPT). The tool yields estimates of K through continuous injection of fluid in the subsurface from a small port on the probe shaft while controlled measurements of net applied fluid pressure required to maintain a specified flow rate (typically 350 mL/min) are recorded. The tool gathers these data of flow rate and measured applied pressure during halted and constant-rate penetration (typically 2cm/sec) of the probe. The analysis is developed in two parts, first to explore the interplay between advective effects controlled by penetration rate and secondly flow volume effects controlled by the targeted flow rate. These two effects are analyzed through their respective influence on the measured applied pressure response in ΔP/σv’-Q/ΔP space, which shows a linear relationship for the flow rate to applied pressure response when Q/ΔP > 1 and when Q/ΔP < 1 the response tends towards an asymptotic limit representing soil failure limits as ΔP/σv’ > 1. The analysis shows that penetration rate does not significantly influence the applied pressure response at the tested penetration rates (0 ≤ U(cm/s)≤ 4). The targeted applied flow rate does however influence the applied pressure response as flow rates less than ~300 mL/min show a scattering of the data in ΔP/σv’-Q/ΔP space, where above 300 mL/min the data begins to form a linear response. A targeted flow rate of QT = 400mL/min is suggested as a suitable flow rate based on this analysis. Measurements of hydraulic conductivity are then obtained for the HPT data through the derivation of an equation based on a recast form of Darcy’s law where considerations of the flow geometry as K = (QHPT/ΔP)(δw/πΦ). K profiles obtained for the HPT system are then compared against K profiles obtained from an independent method (PSU

  12. 40 CFR 725.238 - Activities conducted outside a structure.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Exemptions... certain microorganisms listed in § 725.239 may be conducted without prior review by EPA if all of the... microorganism listed in § 725.239 must be conducted by, or directly under the supervision of, a...

  13. 40 CFR 725.238 - Activities conducted outside a structure.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Exemptions... certain microorganisms listed in § 725.239 may be conducted without prior review by EPA if all of the... microorganism listed in § 725.239 must be conducted by, or directly under the supervision of, a...

  14. 40 CFR 725.238 - Activities conducted outside a structure.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Exemptions... certain microorganisms listed in § 725.239 may be conducted without prior review by EPA if all of the... microorganism listed in § 725.239 must be conducted by, or directly under the supervision of, a...

  15. Improvements to the FATOLA computer program including added actively controlled landing gear subroutines

    NASA Technical Reports Server (NTRS)

    Mall, G. H.

    1983-01-01

    Modifications to a multi-degree-of-freedom flexible aircraft take-off and landing analysis (FATOLA) computer program, including a provision for actively controlled landing gears to expand the programs simulation capabilities, are presented. Supplemental instructions for preparation of data and for use of the modified program are included.

  16. Numerical model of heat conduction in active volcanoes induced by magmatic activity

    NASA Astrophysics Data System (ADS)

    Atmojo, Antono Arif; Rosandi, Yudi

    2015-09-01

    We study the heat transfer mechanism of active volcanoes using the numerical thermal conduction model. A 2D model of volcano with its conduit filled by magma is considered, and acts as a constant thermal source. The temperature of the magma activity diffuses through the rock layers of the mountain to the surface. The conduction equation is solved using finite-difference method, with some adaptations to allow temperature to flow through different materials. Our model allows to simulate volcanoes having dikes, branch-pipes, and sills by constructing the domain appropriately, as well as layers with different thermal properties. Our research will show the possibility to monitor magma activity underneath a volcano by probing its surface temperature. The result of our work will be very useful for further study of volcanoes, eruption prediction, and volcanic disaster mitigation.

  17. [The activation effect of nobiletin on cystic fibrosis transmembrane conductance regulator chloride channel].

    PubMed

    Yang, Shuang; Yu, Bo; Zhang, Yao-Fang; Wang, Xue; Yang, Hong

    2013-06-01

    Aim of the present study is to investigate activation effect of nobiletin on cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel activity. CFTR-mediated iodide influx assay and patch-clamp tests were done on FRT cells stably co-transfected with human CFTR and EYFP/H148Q. Nobiletin potently activated CFTR chloride channel activity in a dose- and time-dependent manner. The CFTR blocker CFTR(inh)-172 could completely reverse the effect. Preliminary mechanism study indicated that nobiletin activated CFTR chloride channel through a direct binding way. In addition, ex vivo tests done on mice trachea showed that nobiletin time-dependently stimulated submucosal gland fluid secretion. Nobiletin may be a therapeutic lead compound in treating CFTR-related diseases including disseminated bronchiectasis.

  18. Electrode including porous particles with embedded active material for use in a secondary electrochemical cell

    DOEpatents

    Vissers, Donald R.; Nelson, Paul A.; Kaun, Thomas D.; Tomczuk, Zygmunt

    1978-04-25

    Particles of carbonaceous matrices containing embedded electrode active material are prepared for vibratory loading within a porous electrically conductive substrate. In preparing the particles, active materials such as metal chalcogenides, solid alloys of alkali or alkaline earth metals along with other metals and their oxides in powdered or particulate form are blended with a thermosetting resin and particles of a volatile to form a paste mixture. The paste is heated to a temperature at which the volatile transforms into vapor to impart porosity at about the same time as the resin begins to cure into a rigid, solid structure. The solid structure is then comminuted into porous, carbonaceous particles with the embedded active material.

  19. Formative Research Conducted in Rural Appalachia to Inform a Community Physical Activity Intervention

    PubMed Central

    Kruger, Tina M.; Swanson, Mark; Davis, Rian E.; Wright, Sherry; Dollarhide, Katie; Schoenberg, Nancy E.

    2011-01-01

    Purpose Despite the well-established benefits of physical activity (PA), most Americans, especially those in rural, traditionally underserved areas, engage in considerably less PA than recommended. This study examines perceived barriers to and facilitators of PA and promising organized PA programs among rural Appalachians. Design Eight focus groups and seven group key informant interviews were conducted. Setting This study was conducted in eastern Kentucky, in Central Appalachia. Subjects 114 rural Appalachian residents (74% female, 91% White) participated. Measures Open-ended, semi-structured, and structured questions regarding perceptions of, barriers to/facilitators of, and examples of successful/failed PA programs were asked. Analysis Qualitative data analysis was conducted, including codebook development and steps taken to ensure rigor and transferability. Interrater reliability was over 94%. Results In addition to barriers that are consistent with other populations, rural Appalachian residents indicated that travel time, family commitments, and inadequate community resources undermine PA. Suggested avenues to increase PA include partnership with churches and the U.S. Cooperative Extension Service; programs that include families, are well-advertised, focus on health rather than appearance; and, underlying all suggestions, culturally-relevant yet non-stereotyping activities. Conclusions When developing PA interventions in rural Appalachia, it is important to employ community-based participatory approaches that leverage unique assets of the population and show potential in overcoming challenges to PA. PMID:22208411

  20. Population and Human Development: A Course Curriculum Including Lesson Plans, Activities, and Bibliography. Revised.

    ERIC Educational Resources Information Center

    Murphy, Elaine M.; Long, Alison T.

    This course outline suggests materials and learning activities on the interrelated causes and consequences of population growth and other population matters. The document describes 15 class sessions which integrate information for sociology, anthropology, psychology, biology, animal behavior, and education. Topics include the history of human…

  1. 76 FR 10385 - Agency Information Collection Activities: Various Contract Related Forms That Will be Included in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-24

    ... SECURITY Agency Information Collection Activities: Various Contract Related Forms That Will be Included in the Homeland Security Acquisition Regulation, DHS FORM 0700-01, DHS FORM 0700-02, DHS FORM 0700-03...: The Department of Homeland Security, Office of Chief Procurement Officer, Acquisition Policy...

  2. 12 CFR 7.5008 - Location of a national bank conducting electronic activities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Location of a national bank conducting electronic activities. 7.5008 Section 7.5008 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY BANK ACTIVITIES AND OPERATIONS Electronic Activities § 7.5008 Location of a national bank conducting electronic activities. A national...

  3. Histamine modulates thalamocortical activity by activating a chloride conductance in ferret perigeniculate neurons.

    PubMed

    Lee, Kendall H; Broberger, Christian; Kim, Uhnoh; McCormick, David A

    2004-04-27

    In the mammalian central nervous system only gamma-aminobutyric acid (GABA) and glycine have been firmly linked to inhibition of neuronal activity through increases in membrane Cl(-) conductance, and these responses are mediated by ionotropic receptors. Iontophoretic application of histamine can also cause inhibitory responses in vivo, although the mechanisms of this inhibition are unknown and may involve pre- or postsynaptic factors. Here, we report that application of histamine to the GABAergic neurons of the thalamic perigeniculate nucleus (PGN), which is innervated by histaminergic fibers from the tuberomammillary nucleus of the hypothalamus, causes a slow membrane hyperpolarization toward a reversal potential of -73 mV through a relatively small increase in membrane conductance to Cl(-). This histaminergic action appears to be mediated by the H(2) subclass of histaminergic receptors and inhibits the single-spike activity of these PGN GABAergic neurons. Application of histamine to the PGN could halt the generation of spindle waves, indicating that increased activity in the tuberomammillary histaminergic system may play a functional role in dampening thalamic oscillations in the transition from sleep to arousal.

  4. 30 CFR 585.614 - When may I begin conducting activities under my approved SAP?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... approved SAP? 585.614 Section 585.614 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF... CONTINENTAL SHELF Plans and Information Requirements Activities Under An Approved Sap § 585.614 When may I begin conducting activities under my approved SAP? (a) You may begin conducting the activities...

  5. 30 CFR 285.614 - When may I begin conducting activities under my approved SAP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... approved SAP? 285.614 Section 285.614 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE... Plans and Information Requirements Activities Under An Approved Sap § 285.614 When may I begin conducting activities under my approved SAP? (a) You may begin conducting the activities approved in your...

  6. 30 CFR 585.614 - When may I begin conducting activities under my approved SAP?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... approved SAP? 585.614 Section 585.614 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF... CONTINENTAL SHELF Plans and Information Requirements Activities Under An Approved Sap § 585.614 When may I begin conducting activities under my approved SAP? (a) You may begin conducting the activities...

  7. 30 CFR 585.614 - When may I begin conducting activities under my approved SAP?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... approved SAP? 585.614 Section 585.614 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF... CONTINENTAL SHELF Plans and Information Requirements Activities Under An Approved Sap § 585.614 When may I begin conducting activities under my approved SAP? (a) You may begin conducting the activities...

  8. Active seat suspension for a small vehicle: considerations for control system including observer

    NASA Astrophysics Data System (ADS)

    Katsumata, Hiroyuki; Shiino, Hiroshi; Oshinoya, Yasuo; Ishibashi, Kazuhisa; Ozaki, Koichi; Ogino, Hirohiko

    2007-12-01

    We have examined the improvement of ride quality and the reduction of riding fatigue brought about by the active control of the seat suspension of small vehicles such as one-seater electric automobiles. A small active seat suspension, which is easy to install, was designed and manufactured for one-seater electric automobiles. For the actuator, a maintenance-free voice coil motor used as a direct drive was adopted. For fundamental considerations, we designed a one-degree-of-freedom model for the active seat suspension system. Then, we designed a disturbance cancellation control system that includes the observer for a two-degree-of-freedom model. In an actual driving test, a test road, in which the concavity and convexity of an actual road surface were simulated using hard rubber, was prepared and the control performance of vertical vibrations of the seat surface during driving was examined. As a result, in comparison with the one-degree-of-freedom control system, it was confirmed that the control performance was improved by the two-degree-of-freedom control system that includes the observer.

  9. Enzymatically active 2',5'-oligoadenylate synthetases are widely distributed among Metazoa, including protostome lineage.

    PubMed

    Päri, Mailis; Kuusksalu, Anne; Lopp, Annika; Kjaer, Karina Hansen; Justesen, Just; Kelve, Merike

    2014-02-01

    2',5'-Oligoadenylate synthetases (OASs) belong to the nucleotidyl transferase family together with poly(A) polymerases, CCA-adding enzymes and the recently discovered cyclic-GMP-AMP synthase (cGAS). Mammalian OASs have been thoroughly characterized as components of the interferon-induced antiviral system. The OAS activity and the respective genes were also discovered in marine sponges where the interferon system is absent. In this study the recombinant OASs from several multicellular animals and their closest unicellular relative, a choanoflagellate, were expressed in a bacterial expression system and their enzymatic activities were examined. We demonstrated 2-5A synthesizing activities of OASs from the marine sponge Tedania ignis, a representative of the phylogenetically oldest metazoan phylum (Porifera), from an invertebrate of the protostome lineage, the mollusk Mytilus californianus (Mollusca), and from a vertebrate species, a cartilaginous fish Leucoraja erinacea (Chordata). However, the expressed proteins from an amphibian, the salamander Ambystoma mexicanum (Chordata), and from a protozoan, the marine choanoflagellate Monosiga brevicollis (Choanozoa), did not show 2-5A synthesizing activity. Differently from other studied OASs, OAS from the marine sponge T. ignis was able to catalyze the formation of oligomers having both 2',5'- and 3',5'-phosphodiester linkages. Our data suggest that OASs from sponges and evolutionarily higher animals have similar activation mechanisms which still include different affinities and possibly different structural requirements for the activating RNAs. Considering their 2'- and 3'-specificities, sponge OASs could represent a link between evolutionarily earlier nucleotidyl transferases and 2'-specific OASs from higher animals.

  10. Enzymatically active 2',5'-oligoadenylate synthetases are widely distributed among Metazoa, including protostome lineage.

    PubMed

    Päri, Mailis; Kuusksalu, Anne; Lopp, Annika; Kjaer, Karina Hansen; Justesen, Just; Kelve, Merike

    2014-02-01

    2',5'-Oligoadenylate synthetases (OASs) belong to the nucleotidyl transferase family together with poly(A) polymerases, CCA-adding enzymes and the recently discovered cyclic-GMP-AMP synthase (cGAS). Mammalian OASs have been thoroughly characterized as components of the interferon-induced antiviral system. The OAS activity and the respective genes were also discovered in marine sponges where the interferon system is absent. In this study the recombinant OASs from several multicellular animals and their closest unicellular relative, a choanoflagellate, were expressed in a bacterial expression system and their enzymatic activities were examined. We demonstrated 2-5A synthesizing activities of OASs from the marine sponge Tedania ignis, a representative of the phylogenetically oldest metazoan phylum (Porifera), from an invertebrate of the protostome lineage, the mollusk Mytilus californianus (Mollusca), and from a vertebrate species, a cartilaginous fish Leucoraja erinacea (Chordata). However, the expressed proteins from an amphibian, the salamander Ambystoma mexicanum (Chordata), and from a protozoan, the marine choanoflagellate Monosiga brevicollis (Choanozoa), did not show 2-5A synthesizing activity. Differently from other studied OASs, OAS from the marine sponge T. ignis was able to catalyze the formation of oligomers having both 2',5'- and 3',5'-phosphodiester linkages. Our data suggest that OASs from sponges and evolutionarily higher animals have similar activation mechanisms which still include different affinities and possibly different structural requirements for the activating RNAs. Considering their 2'- and 3'-specificities, sponge OASs could represent a link between evolutionarily earlier nucleotidyl transferases and 2'-specific OASs from higher animals. PMID:24184688

  11. Plants as sources of airborne bacteria, including ice nucleation-active bacteria.

    PubMed

    Lindemann, J; Constantinidou, H A; Barchet, W R; Upper, C D

    1982-11-01

    Vertical wind shear and concentration gradients of viable, airborne bacteria were used to calculate the upward flux of viable cells above bare soil and canopies of several crops. Concentrations at soil or canopy height varied from 46 colony-forming units per m over young corn and wet soil to 663 colony-forming units per m over dry soil and 6,500 colony-forming units per m over a closed wheat canopy. In simultaneous samples, concentrations of viable bacteria in the air 10 m inside an alfalfa field were fourfold higher than those over a field with dry, bare soil immediately upwind. The upward flux of viable bacteria over alfalfa was three- to fourfold greater than over dry soil. Concentrations of ice nucleation-active bacteria were higher over plants than over soil. Thus, plant canopies may constitute a major source of bacteria, including ice nucleation-active bacteria, in the air.

  12. Visible-light active conducting polymer nanostructures with superior photocatalytic activity

    PubMed Central

    Ghosh, Srabanti; Kouame, Natalie Amoin; Remita, Samy; Ramos, Laurence; Goubard, Fabrice; Aubert, Pierre-Henri; Dazzi, Alexandre; Deniset-Besseau, Ariane; Remita, Hynd

    2015-01-01

    The development of visible-light responsive photocatalysts would permit more efficient use of solar energy, and thus would bring sustainable solutions to many environmental issues. Conductive polymers appear as a new class of very active photocatalysts under visible light. Among them poly(3,4-ethylenedioxythiophene) (PEDOT) is one of the most promising conjugated polymer with a wide range of applications. PEDOT nanostructures synthesized in soft templates via chemical oxidative polymerization demonstrate unprecedented photocatalytic activities for water treatment without the assistance of sacrificial reagents or noble metal co-catalysts and turn out to be better than TiO2 as benchmark catalyst. The PEDOT nanostructures exhibit a narrow band gap (E = 1.69 eV) and are characterized by excellent ability to absorb light in visible and near infrared region. The novel PEDOT-based photocatalysts are very stable with cycling and can be reused without appreciable loss of activity. Interestingly, hollow micrometric vesicular structures of PEDOT are not effective photocatalysts as compared to nanometric spindles suggesting size and shape dependent photocatalytic properties. The visible-light active photocatalytic properties of the polymer nanostructures present promising applications in solar light harvesting and broader fields. PMID:26657168

  13. Measuring and Reducing Off-Target Activities of Programmable Nucleases Including CRISPR-Cas9.

    PubMed

    Koo, Taeyoung; Lee, Jungjoon; Kim, Jin-Soo

    2015-06-01

    Programmable nucleases, which include zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and RNA-guided engineered nucleases (RGENs) repurposed from the type II clustered, regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) system are now widely used for genome editing in higher eukaryotic cells and whole organisms, revolutionising almost every discipline in biological research, medicine, and biotechnology. All of these nucleases, however, induce off-target mutations at sites homologous in sequence with on-target sites, limiting their utility in many applications including gene or cell therapy. In this review, we compare methods for detecting nuclease off-target mutations. We also review methods for profiling genome-wide off-target effects and discuss how to reduce or avoid off-target mutations.

  14. Multiple conductance states of the light-activated channel of Limulus ventral photoreceptors. Alteration of conductance state during light

    PubMed Central

    1991-01-01

    The properties of light-dependent channels in Limulus ventral photoreceptors have been studied in cell-attached patches. Two sizes of single-channel events are seen during illumination. Previous work has characterized the large (40 pS) events; the goal of the current work was to characterize the small (15 pS) events and determine their relationship to the large events. The small events are activated by light rather than as a secondary result of the change in membrane voltage during light. The mean open time of the small events is 1.34 +/- 0.49 ms (mean +/- SD, n = 15), approximately 50% of that of the large events. The large and small events have the same reversal potential and a similar dependence of open-state probability on voltage. Evidence that these events are due to different conductance states of the same channel comes from analysis of relatively infrequent events showing a direct transition between the 15 and 40-pS levels. Furthermore, large and small events do not superpose, even at positive voltages when the probability of being open is very high, as would be predicted if the two-sized events were due to independent channels. Expression of the different conductance states is not random; during steady illumination there are alternating periods of several hundred milliseconds in which there are consecutive, sequential large events followed by periods in which there are consecutive, sequential small events. At early times during the response to a step of light, the large conductance state is preferentially expressed. At later times, there is an increase in the relative contribution of the low conductance state. These findings indicate that there is a process that changes the preferred conductance state of the channel. This alteration has functional importance in the process of light adaptation. PMID:1875187

  15. Stability and activity of alcohol dehydrogenases in W/O-microemulsions: enantioselective reduction including cofactor regeneration.

    PubMed

    Orlich, B; Berger, H; Lade, M; Schomäcker, R

    2000-12-20

    Microemulsions provide an interesting alternative to classical methods for the conversion of less water-soluble substrates by alcohol dehydrogenase, but until now stability and activity were too low for economically useful processes. The activity and stability of the enzymes are dependent on the microemulsion composition, mostly the water and the surfactant concentration. Therefore, it is necessary to know the exact phase behavior of a given microemulsion reaction system and the corresponding enzyme behavior therein. Because of their economic and ecologic suitability polyethoxylated fatty alcohols were investigated concerning their phase behavior and their compatibility with enzymes in ternary mixtures. The phase behavior of Marlipal O13-60 (C13EO6 in industrial quality)/cyclohexane/water and its effect on the activity and stability of alcohol dehydrogenase from Yeast (YADH) and horse liver (HLADH) and the carbonyl reductase from Candida parapsilosis (CPCR) is presented in this study. Beside the macroscopic phase behavior of the reaction system, the viscosity of the system indicates structural changes of aggregates in the microemulsion. The changes of the enzyme activities with the composition are discussed on the basis of transitions from reverse micelles to swollen reverse micelles and finally, the transition to the phase separation. The formate dehydrogenase from Candida boidinii was used for the NADH-regeneration during reduction reactions. While the formate dehydrogenase did not show any kinetic effect on the microemulsion composition, the other enzymes show significant changes of activity and stability varying the water or surfactant concentration of the microemulsion. Under certain conditions, stability could be maintained with HLADH for several weeks. Successful experiments with semi-batch processes including cofactor regeneration and product separation were performed.

  16. 78 FR 44624 - Proposed Information Collection (Conduct the Point-of-Care Research Questionnaire); Activities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-24

    ... AFFAIRS [OMB Control No. 2900-NEW (Conduct the Point-of-Care Research Questionnaire)] Proposed Information Collection (Conduct the Point-of-Care Research Questionnaire); Activities Under OMB Review AGENCY: Veterans...) 395-7316. Please refer to ``OMB Control No. 2900-NEW (Conduct the Point of Care Research...

  17. Voltage-activated K+ conductances in freshly isolated embryonic chicken osteoclasts.

    PubMed

    Ravesloot, J H; Ypey, D L; Vrijheid-Lammers, T; Nijweide, P J

    1989-09-01

    Patch-clamp measurements on freshly isolated embryonic chicken osteoclasts revealed three distinct types of voltage-dependent K+ conductance. The first type of conductance, present in 72% of the cells, activated at membrane potentials less negative than -30 to -20 mV and reached full activation at +40 mV. It activated with a delay, reached a peak value, and then inactivated with a time constant of approximately 1.5 s. Inactivation was complete or almost so. Recovery from inactivation, at -70 mV, had a time constant of roughly 1 s. The conductance could be blocked, at least partly, by 4 mM 4-aminopyridine. The second type of conductance (present in all cells) activated at membrane potentials more negative than -40 to -80 mV and reached full activation at -130 mV. Activation potential and maximal conductance were dependent on the extracellular K+ concentration. Inactivation of the conductance first became apparent at membrane potentials more negative than -100 mV and was a two-exponential process. The conductance could be blocked by external 5 mM Cs+ ions. The third type of conductance (present in all cells) activated at membrane potentials more positive than +30 mV. Generally, the conductance did not inactivate.

  18. 30 CFR 285.614 - When may I begin conducting activities under my approved SAP?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... approved SAP? 285.614 Section 285.614 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND... OUTER CONTINENTAL SHELF Plans and Information Requirements Activities Under An Approved Sap § 285.614 When may I begin conducting activities under my approved SAP? (a) You may begin conducting...

  19. 30 CFR 550.208 - If I conduct ancillary activities, what notices must I provide?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false If I conduct ancillary activities, what notices must I provide? 550.208 Section 550.208 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT... least 30 calendar days before you conduct any G&G exploration or development G&G activity (see §...

  20. 30 CFR 550.208 - If I conduct ancillary activities, what notices must I provide?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false If I conduct ancillary activities, what notices must I provide? 550.208 Section 550.208 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT... least 30 calendar days before you conduct any G&G exploration or development G&G activity (see §...

  1. 30 CFR 550.208 - If I conduct ancillary activities, what notices must I provide?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false If I conduct ancillary activities, what notices must I provide? 550.208 Section 550.208 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT... least 30 calendar days before you conduct any G&G exploration or development G&G activity (see §...

  2. 26 CFR 1.355-3 - Active conduct of a trade or business.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... defined—(1) In general. Section 355(b)(2) provides rules for determining whether a corporation is treated... section 355(b)(2)(A), a corporation is treated as engaged in the active conduct of a trade or business if... section 355(b), a corporation shall be treated as engaged in the “active conduct of a trade or...

  3. 12 CFR 362.15 - Acquiring or establishing a subsidiary; conducting new activities through a subsidiary.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INSURED SAVINGS ASSOCIATIONS Acquiring, Establishing, or Conducting New Activities Through a Subsidiary by an Insured Savings Association § 362.15 Acquiring or establishing a subsidiary; conducting new activities through a subsidiary. No state or Federal insured savings association may establish or acquire...

  4. The EMT-activator ZEB1 induces bone metastasis associated genes including BMP-inhibitors

    PubMed Central

    Mock, Kerstin; Preca, Bogdan-Tiberius; Brummer, Tilman; Brabletz, Simone; Stemmler, Marc P.; Brabletz, Thomas

    2015-01-01

    Tumor cell invasion, dissemination and metastasis is triggered by an aberrant activation of epithelial-to-mesenchymal transition (EMT), often mediated by the transcription factor ZEB1. Disseminating tumor cells must acquire specific features that allow them to colonize at different organ sites. Here we identify a set of genes that is highly expressed in breast cancer bone metastasis and activated by ZEB1. This gene set includes various secreted factors, e.g. the BMP-inhibitor FST, that are described to reorganize the bone microenvironment. By inactivating BMP-signaling, BMP-inhibitors are well-known to induce osteolysis in development and disease. We here demonstrate that the expression of ZEB1 and BMP-inhibitors is correlated with bone metastasis, but not with brain or lung metastasis of breast cancer patients. In addition, we show that this correlated expression pattern is causally linked, as ZEB1 induces the expression of the BMP-inhibitors NOG, FST and CHRDL1 both by directly increasing their gene transcription, as well as by indirectly suppressing their reduction via miR-200 family members. Consequently, ZEB1 stimulates BMP-inhibitor mediated osteoclast differentiation. These findings suggest that ZEB1 is not only driving EMT, but also contributes to the formation of osteolytic bone metastases in breast cancer. PMID:25973542

  5. Be BOLD: Encouraging Girls to Include Unstructured Bouts of Physical Activity into Daily Routines

    ERIC Educational Resources Information Center

    Hill, Kory; Williams, Gwynne M.

    2014-01-01

    Adolescent girls are less active than their male counterparts and physical activity levels tend to decline as one ages. One of the goals of concerned physical educators is to promote a physically active lifestyle and to teach skills and promote behaviors that will allow students to be active both in and out of school. This article presents a…

  6. Active control of environmental noise, VIII: increasing the response to primary source changes including unpredictable noise

    NASA Astrophysics Data System (ADS)

    Wright, S. E.; Atmoko, H.; Vuksanovic, B.

    2004-07-01

    Conventional adaptive cancellation systems using traditional transverse finite impulse response (FIR) filters, together with least mean square (LMS) adaptive algorithms, well known in active noise control, are slow to adapt to primary source changes. This makes them inappropriate for cancelling rapidly changing noise, including unpredictable noise such as speech and music. Secondly, the cancelling structures require considerable computational processing effort to adapt to primary source and plant changes, particularly for multi-channel systems. This paper describes methods to increase the adaptive speed to primary source changes in large enclosed spaces and outdoor environments. A method is described that increases the response to time varying periodic noise using traditional transverse FIR filters. Here a multi-passband filter, with individual variable adaptive step sizes for each passband is automatically adjusted according to the signal level in each band. This creates a similar adaptive response for all frequencies within the total pass-band, irrespective of amplitude, minimizing the signal distortion and increasing the combined adaptive speed. Unfortunately, there is a limit to the adaptive speed using the above method as classical transverse FIR filters have a finite adaptive speed given by the stability band zero bandwidth. For rapidly changing periodic noise and unpredictable non-stationary noise, a rapid to instantaneous response is required. In this case the on-line adaptive FIR filters are dispensed with and replaced by a time domain solution that gives virtually instantaneous cancellation response (infinite adaptive speed) to primary source changes, and is computationally efficient.

  7. A calcium-permeable cGMP-activated cation conductance in hippocampal neurons

    NASA Technical Reports Server (NTRS)

    Leinders-Zufall, T.; Rosenboom, H.; Barnstable, C. J.; Shepherd, G. M.; Zufall, F.

    1995-01-01

    Whole-cell patch clamp recordings detected a previously unidentified cGMP-activated membrane conductance in cultured rat hippocampal neurons. This conductance is nonselectively permeable for cations and is completely but reversibly blocked by external Cd2+. The Ca2+ permeability of the hippocampal cGMP-activated conductance was examined in detail, indicating that the underlying ion channels display a high relative permeability for Ca2+. The results indicate that hippocampal neurons contain a cGMP-activated membrane conductance that has some properties similar to the cyclic nucleotide-gated channels previously shown in sensory receptor cells and retinal neurons. In hippocampal neurons this conductance similarly could mediate membrane depolarization and Ca2+ fluxes in response to intracellular cGMP elevation.

  8. 45 CFR 287.130 - Can NEW Program activities include job market assessments, job creation and economic development...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 2 2011-10-01 2011-10-01 false Can NEW Program activities include job market assessments, job creation and economic development activities? 287.130 Section 287.130 Public Welfare... Program Design and Operations § 287.130 Can NEW Program activities include job market assessments,...

  9. 45 CFR 287.130 - Can NEW Program activities include job market assessments, job creation and economic development...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 2 2012-10-01 2012-10-01 false Can NEW Program activities include job market assessments, job creation and economic development activities? 287.130 Section 287.130 Public Welfare... Program Design and Operations § 287.130 Can NEW Program activities include job market assessments,...

  10. 45 CFR 287.130 - Can NEW Program activities include job market assessments, job creation and economic development...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Can NEW Program activities include job market assessments, job creation and economic development activities? 287.130 Section 287.130 Public Welfare... Program Design and Operations § 287.130 Can NEW Program activities include job market assessments,...

  11. 45 CFR 287.130 - Can NEW Program activities include job market assessments, job creation and economic development...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 2 2014-10-01 2012-10-01 true Can NEW Program activities include job market assessments, job creation and economic development activities? 287.130 Section 287.130 Public Welfare... Program Design and Operations § 287.130 Can NEW Program activities include job market assessments,...

  12. 45 CFR 287.130 - Can NEW Program activities include job market assessments, job creation and economic development...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 2 2013-10-01 2012-10-01 true Can NEW Program activities include job market assessments, job creation and economic development activities? 287.130 Section 287.130 Public Welfare... Program Design and Operations § 287.130 Can NEW Program activities include job market assessments,...

  13. 30 CFR 250.208 - If I conduct ancillary activities, what notices must I provide?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false If I conduct ancillary activities, what notices must I provide? 250.208 Section 250.208 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION... notices must I provide? At least 30 calendar days before you conduct any G&G exploration or development...

  14. Sociological Understandings of Conduct for a Noncanonical Activity Theory: Exploring Intersections and Complementarities

    ERIC Educational Resources Information Center

    Sawchuk, Peter H.; Stetsenko, Anna

    2008-01-01

    Following a discussion of activity theory as an approach to human development originally rooted in transformational change, we review the historical context and diverse conceptualizations of social conduct from the field of sociology. The discussion of social conduct is broken into theories of social action, theories of enactment, and contemporary…

  15. Atrial conduction times and left atrium mechanical functions in patients with active acromegaly.

    PubMed

    Ilter, A; Kırış, A; Kaplan, Ş; Kutlu, M; Şahin, M; Erem, C; Civan, N; Kangül, F

    2015-03-01

    The aim of this study was to evaluate atrial electromechanical delay (EMD), P wave dispersion (Pwd), and left atrial (LA) mechanical functions in patients with active acromegaly. Twenty-three patients with active acromegaly and 27 age- and sex-matched controls were included in this study. All atrial electromechanical interval parameters (PA lateral, PA septum, PA tricuspid, interatrial EMD, intra-LA EMD, and intra-right atrial EMD) were measured from mitral lateral annulus, mitral septal annulus, and right ventricular tricuspid annulus by tissue Doppler imaging. LA volumes were measured by the disk method in the apical four-chamber view and were indexed to the body surface area. Mechanical function parameters of LA were calculated. Pwd was performed by 12-lead electrocardiograms. Atrial electromechanical intervals (PA lateral, PA septum, PA tricuspid, interatrial EMD, intra-LA EMD, and intra-right atrial EMD) and Pwd were similar between patients with acromegaly and control subjects (all p > 0.05). LA volumes (maximum, minimum, and presystolic) and LA mechanical functions were not significantly different between the groups (all p > 0.05). Additionally, serum levels of growth hormone and insulin-like growth factor-1 were not correlated with atrial electromechanical parameters and LA mechanical functions. Atrial electrical conduction times were not prolonged and LA mechanical functions were not impaired in patients with active acromegaly compared with controls. And the prevalence of supraventricular arrhythmia risk may not increase in this population.

  16. A Systematic Examination of School Improvement Activities That Include Special Education

    ERIC Educational Resources Information Center

    Duchnowski, A.J.; Kutash, K.; Oliveira, B.

    2004-01-01

    Methodological and practical challenges present formidable barriers to conducting empirical evaluations of school reform initiatives. Systematic information about school reform and improvement, and its relationship to special education, is even more difficult to obtain. In this study, the authors developed a reliable and valid method to (a)…

  17. Thermal conductivity of steam from 250 to 510°C at pressures up to 95 MPa including the critical region

    NASA Astrophysics Data System (ADS)

    Tufeu, R.; Le Neindre, B.

    1987-05-01

    New measurements of the thermal conductivity of steam have been performed in the temperature range 250 510°C and in the pressure range from 1 up to 95 MPa. Most of the measurements were taken at temperatures greater than the critical temperature, where the enhancement of the thermal conductivity is observed. The experimental values are compared to the IAPS formulation for the thermal conductivity of water.

  18. Thermal conductivity of steam from 250 to 510/sup 0/C at pressures up to 95 MPa including the critical region

    SciTech Connect

    Tufeu, R.; Le Neindre, B.

    1987-05-01

    New measurements of the thermal conductivity of steam have been performed in the temperature range 250-510/sup 0/C and in the pressure range from 1 up to 95 MPa. Most of the measurements were taken at temperatures greater than the critical temperature, where the enhancement of the thermal conductivity is observed. The experimental values are compared to the IAPS formulation for the thermal conductivity of water.

  19. Estimation of excitatory and inhibitory synaptic conductance variations in motoneurons during locomotor-like rhythmic activity.

    PubMed

    Kobayashi, Ryota; Nishimaru, Hiroshi; Nishijo, Hisao

    2016-10-29

    The rhythmic activity of motoneurons (MNs) that underlies locomotion in mammals is generated by synaptic inputs from the locomotor network in the spinal cord. Thus, the quantitative estimation of excitatory and inhibitory synaptic conductances is essential to understand the mechanism by which the network generates the functional motor output. Conductance estimation is obtained from the voltage-current relationship measured by voltage-clamp- or current-clamp-recording with knowledge of the leak parameters of the recorded neuron. However, it is often difficult to obtain sufficient data to estimate synaptic conductances due to technical difficulties in electrophysiological experiments using in vivo or in vitro preparations. To address this problem, we estimated the average variations in excitatory and inhibitory synaptic conductance during a locomotion cycle from a single voltage trace without measuring the leak parameters. We found that the conductance variations can be accurately reconstructed from a voltage trace of 10 cycles by analyzing synthetic data generated from a computational model. Next, the conductance variations were estimated from mouse spinal MNs in vitro during drug-induced-locomotor-like activity. We found that the peak of excitatory conductance occurred during the depolarizing phase of the locomotor cycle, whereas the peak of inhibitory conductance occurred during the hyperpolarizing phase. These results suggest that the locomotor-like activity is generated by push-pull modulation via excitatory and inhibitory synaptic inputs. PMID:27561702

  20. Using Assistive Technology Adaptations To Include Students with Learning Disabilities in Cooperative Learning Activities.

    ERIC Educational Resources Information Center

    Bryant, Diane Pedrotty; Bryant, Brian R.

    1998-01-01

    Discusses a process for integrating technology adaptations for students with learning disabilities into cooperative-learning activities in terms of three components: (1) selecting adaptations; (2) monitoring use of adaptations during cooperative-learning activities; and (3) evaluating the adaptations' effectiveness. Barriers to and support systems…

  1. 39 CFR 255.3 - Nondiscrimination under any program or activity conducted by the Postal Service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 39 Postal Service 1 2012-07-01 2012-07-01 false Nondiscrimination under any program or activity conducted by the Postal Service. 255.3 Section 255.3 Postal Service UNITED STATES POSTAL SERVICE ORGANIZATION AND ADMINISTRATION ACCESS OF PERSONS WITH DISABILITIES TO POSTAL SERVICE PROGRAMS, ACTIVITIES, FACILITIES, AND ELECTRONIC AND...

  2. 30 CFR 285.1010 - How long may I conduct activities under an Alternate Use RUE?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Alternate Use RUE? 285.1010 Section 285.1010 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION... Activities Using Existing OCS Facilities Alternate Use Rue Administration § 285.1010 How long may I conduct activities under an Alternate Use RUE? (a) We will establish on a case-by-case basis, and set forth in...

  3. 21 CFR 312.87 - Active monitoring of conduct and evaluation of clinical trials.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Active monitoring of conduct and evaluation of clinical trials. 312.87 Section 312.87 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... to Treat Life-threatening and Severely-debilitating Illnesses § 312.87 Active monitoring of...

  4. 21 CFR 312.87 - Active monitoring of conduct and evaluation of clinical trials.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Active monitoring of conduct and evaluation of clinical trials. 312.87 Section 312.87 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... to Treat Life-threatening and Severely-debilitating Illnesses § 312.87 Active monitoring of...

  5. 21 CFR 312.87 - Active monitoring of conduct and evaluation of clinical trials.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Active monitoring of conduct and evaluation of clinical trials. 312.87 Section 312.87 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... to Treat Life-threatening and Severely-debilitating Illnesses § 312.87 Active monitoring of...

  6. 21 CFR 312.87 - Active monitoring of conduct and evaluation of clinical trials.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Active monitoring of conduct and evaluation of clinical trials. 312.87 Section 312.87 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... to Treat Life-threatening and Severely-debilitating Illnesses § 312.87 Active monitoring of...

  7. 75 FR 79342 - Taking and Importing Marine Mammals; Navy Training Activities Conducted Within the Northwest...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-20

    ... preamble to the final rule (75 FR 69296, November 10, 2010), that the taking resulting from the activities... findings, described in the preamble to the final rule (75 FR 45527, August 3, 2010), that the taking... Training Activities Conducted Within the Northwest Training Range Complex (NWTRC) and Military...

  8. Functional characteristics and molecular identification of swelling-activated chloride conductance in adult rabbit heart ventricles.

    PubMed

    Li, Jingdong; Wu, Xiangqiong; Cui, Tianpen

    2008-02-01

    Outwardly rectifying swelling-activated chloride conductance (ICl,Swell) in rabbit heart plays a critical role in cardioprotection following ischemic preconditioning (IP). But the functional characterization and molecular basis of this chloride conductance in rabbit heart ventricular myocytes is not clear. Candidate chloride channel clones (e.g. ClC-2, ClC-3, ClC-4 and ClC-5) were determined using RT-PCR and Western blot analysis. Whole cell ICl,Swell was recorded from isolated rabbit ventricular myocytes using patch clamp techniques during hypo-osmotic stress. The inhibitory effects of 4,4' isothiocyanato-2,2-disulfonic acid (DIDS), 5-nitro-2(3-phenylroylamino) benzoic acid (NPPB) and indanyloxyacetic acid 94 (IAA-94) on ICl,Swell were examined. The expected size of PCR products for ClC-2, ClC-3 and ClC-4 but not for ClC-5 was obtained. ClC-2 and ClC-3 expression was confirmed by automated fluorescent DNA sequencing. RT-PCR and Western blot showed that ClC-4 was expressed in abundance and ClC-2 was expressed at somewhat lower levels. The biological and pharmacological properties of I(Cl,Swell), including outward rectification, activation due to cell volume change, sensitivity to DIDS, IAA-94 and NPPB were identical to those known properties of ICl,Swell in exogenously expressed systems and other mammals hearts. It was concluded that ClC-3 or ClC-4 might be responsible for the outwardly rectifying part of ICl,Swell and may be the molecular targets of cardioprotection associated with ischemic preconditioning or hypo-osmotic shock. PMID:18278453

  9. The distribution of intermediate-conductance, calcium-activated, potassium (IK) channels in epithelial cells.

    PubMed

    Thompson-Vest, Nichola; Shimizu, Yasutake; Hunne, Billie; Furness, John B

    2006-02-01

    Intermediate-conductance, calcium-activated, potassium (IK) channels were first identified by their roles in cell volume regulation, and were later shown to be involved in control of proliferation of lymphocytes and to provide a K+ current for epithelial secretory activity. Until now, there has been no systematic investigation of IK channel localization within different epithelia. IK channel immunoreactivity was present in most epithelia, where it occurred in surface membranes of epithelial cells. It was found in all stratified epithelia, including skin, cornea, oral mucosa, vaginal mucosa, urothelium and the oesophageal lining. It occurred in the ducts of fluid-secreting glands, the salivary glands, lacrimal glands and pancreas, and in the respiratory epithelium. A low level of expression was seen in serous acinar cells. It was also found in other epithelia with fluid-exchange properties, the choroid plexus epithelium, the ependyma, visceral pleura and peritoneum, bile ducts and intestinal lining epithelium. However, there was little or no expression in vascular endothelial cells, kidney tubules or collecting ducts, lung alveoli, or in sebaceous glands. It is concluded that the channel is present in surface epithelia (e.g. skin) where it has a cell-protective role against osmotic challenge, and in epithelia where there is anion secretion that is facilitated by a K+ current-dependent hyperpolarization. It was also in some epithelial cells where its roles are as yet unknown. PMID:16441566

  10. Diffractive laser beam homogenizer including a photo-active material and method of fabricating the same

    SciTech Connect

    Bayramian, Andy J; Ebbers, Christopher A; Chen, Diana C

    2014-05-20

    A method of manufacturing a plurality of diffractive optical elements includes providing a partially transmissive slide, providing a first piece of PTR glass, and directing first UV radiation through the partially transmissive slide to impinge on the first piece of PTR glass. The method also includes exposing predetermined portions of the first piece of PTR glass to the first UV radiation and thermally treating the exposed first piece of PTR glass. The method further includes providing a second piece of PTR glass and directing second UV radiation through the thermally treated first piece of PTR glass to impinge on the second piece of PTR glass. The method additionally includes exposing predetermined portions of the second piece of PTR glass to the second UV radiation, thermally treating the exposed second piece of PTR glass, and repeating providing and processing of the second piece of PTR glass using additional pieces of PTR glass.

  11. In vitro and in vivo anti-plasmodial activity of essential oils, including hinokitiol.

    PubMed

    Fujisaki, Ryuichi; Kamei, Kiyoko; Yamamura, Mariko; Nishiya, Hajime; Inouye, Shigeharu; Takahashi, Miki; Abe, Shigeru

    2012-03-01

    Abstract. The anti-plasmodial activity of 47 essential oils and 10 of their constituents were screened for in vitro activity against Plasmodium falciparum. Five of these essential oils (sandalwood, caraway, monarda, nutmeg, and Thujopsis dolabrata var. hondai) and 2 constituents (thymoquinone and hinokitiol) were found to be active against P. falciparum in vitro, with 50% inhibitory concentration (IC50) values equal to or less than 1.0 microg/ml. Furthermore, in vivo analysis using a rodent model confirmed the anti-plasmodial potential of subcutaneously administered sandalwood oil, and percutaneously administered hinokitiol and caraway oil against rodent P. berghei. Notably, these oils showed no efficacy when administered orally, intraperitoneally or intravenously. Caraway oil and hinokitiol dissolved in carrier oil, applied to the skin of hairless mice caused high levels in the blood, with concentrations exceeding their IC50 values. PMID:23082579

  12. In vitro and in vivo anti-plasmodial activity of essential oils, including hinokitiol.

    PubMed

    Fujisaki, Ryuichi; Kamei, Kiyoko; Yamamura, Mariko; Nishiya, Hajime; Inouye, Shigeharu; Takahashi, Miki; Abe, Shigeru

    2012-03-01

    Abstract. The anti-plasmodial activity of 47 essential oils and 10 of their constituents were screened for in vitro activity against Plasmodium falciparum. Five of these essential oils (sandalwood, caraway, monarda, nutmeg, and Thujopsis dolabrata var. hondai) and 2 constituents (thymoquinone and hinokitiol) were found to be active against P. falciparum in vitro, with 50% inhibitory concentration (IC50) values equal to or less than 1.0 microg/ml. Furthermore, in vivo analysis using a rodent model confirmed the anti-plasmodial potential of subcutaneously administered sandalwood oil, and percutaneously administered hinokitiol and caraway oil against rodent P. berghei. Notably, these oils showed no efficacy when administered orally, intraperitoneally or intravenously. Caraway oil and hinokitiol dissolved in carrier oil, applied to the skin of hairless mice caused high levels in the blood, with concentrations exceeding their IC50 values.

  13. Progressive age-associated activation of JNK associates with conduction disruption in the aged atrium.

    PubMed

    Jones, Sandra A; Lancaster, Matthew K

    2015-03-01

    Connexin43 (Cx43) is critical for maintaining electrical conduction across atrial muscle. During progressive ageing atrial conduction slows associating with increasing susceptibility to arrhythmias. Changes in Cx43 protein expression, or its phosphorylation status, can instigate changes in the conduction of the cardiac action potential. This study investigated whether increased levels of activated c-jun N-terminal kinase (JNK) is responsible for the decline of Cx43 during ageing. Right atria from guinea pigs aged between 1 day and 38 months of age were examined. The area of the intercalated disc increased with age concurrent with a 75% decline in C43 protein expression. An age-dependent increase in activated-JNK correlated with a rise in phosphorylated Cx43, but also slowing of action potential conduction velocity across the atria from 0.38±0.01 m/s at 1 month of age to 0.30±0.01 m/s at 38 months. The JNK activator anisomycin increased activated JNK in myocytes and reduced Cx43 protein expression simulating ageing. The JNK inhibitor SP600125, was found to eradicate almost all trace of Cx43 protein. We conclude that in vivo activation of JNK increases with age leading to the loss of Cx43 protein resulting in impaired conduction and contributing to the increasing risk of atrial arrhythmias with advancing age.

  14. Progressive age-associated activation of JNK associates with conduction disruption in the aged atrium

    PubMed Central

    Jones, Sandra A.; Lancaster, Matthew K.

    2015-01-01

    Connexin43 (Cx43) is critical for maintaining electrical conduction across atrial muscle. During progressive ageing atrial conduction slows associating with increasing susceptibility to arrhythmias. Changes in Cx43 protein expression, or its phosphorylation status, can instigate changes in the conduction of the cardiac action potential. This study investigated whether increased levels of activated c-jun N-terminal kinase (JNK) is responsible for the decline of Cx43 during ageing. Right atria from guinea pigs aged between 1 day and 38 months of age were examined. The area of the intercalated disc increased with age concurrent with a 75% decline in C43 protein expression. An age-dependent increase in activated-JNK correlated with a rise in phosphorylated Cx43, but also slowing of action potential conduction velocity across the atria from 0.38 ± 0.01 m/s at 1 month of age to 0.30 ± 0.01 m/s at 38 months. The JNK activator anisomycin increased activated JNK in myocytes and reduced Cx43 protein expression simulating ageing. The JNK inhibitor SP600125, was found to eradicate almost all trace of Cx43 protein. We conclude that in vivo activation of JNK increases with age leading to the loss of Cx43 protein resulting in impaired conduction and contributing to the increasing risk of atrial arrhythmias with advancing age. PMID:25956603

  15. Physical Activity Programs in Higher Education: Modifying Net/Wall Games to Include Individuals with Disabilities

    ERIC Educational Resources Information Center

    Braga, Luciana; Tracy, Julia F.; Taliaferro, Andrea R.

    2015-01-01

    The growing number of students with disabilities in higher education settings has presented challenges for instructors with regards to appropriate inclusion. Concerning physical activity courses in higher education, instructors may not have the knowledge or resources to make modifications and accommodations that will ultimately result in…

  16. Observing a fictitious stressful event: haematological changes, including circulating leukocyte activation.

    PubMed

    Mian, Rubina; Shelton-Rayner, Graham; Harkin, Brendan; Williams, Paul

    2003-03-01

    The aim of this study was to assess the effect of watching a psychological stressful event on the activation of leukocytes in healthy human volunteers. Blood samples were obtained from 32 healthy male and female subjects aged between 20 and 26 years before, during and after either watching an 83-minute horror film that none of the subjects had previously seen (The Texas Chainsaw Massacre, 1974) or by sitting quietly in a room (control group). Total differential cell counts, leukocyte activation as measured by the nitroblue tetrazolium (NBT) test, heart rate and blood pressure (BP) measurements were taken at defined time points. There were significant increases in peripheral circulating leukocytes, the number of activated circulating leukocytes, haemoglobin (Hb) concentration and haematocrit (Hct) in response to the stressor. These were accompanied by significant increases in heart rate, systolic and diastolic BP (P<0.05 from baseline). This is the first reported study on the effects of observing a psychologically stressful, albeit fictitious event on circulating leukocyte numbers and the state of leukocyte activation as determined by the nitrotetrazolium test.

  17. Sixty Minutes of Physical Activity per Day Included within Preschool Academic Lessons Improves Early Literacy

    ERIC Educational Resources Information Center

    Kirk, Stacie M.; Kirk, Erik P.

    2016-01-01

    Background: The effects of increases in physical activity (PA) on early literacy skills in preschool children are not known. Methods: Fifty-four African-American preschool children from a low socioeconomic urban Head Start participated over 8 months. A 2-group, quasi-experimental design was used with one preschool site participating in the PA…

  18. Population and Human Development: A Course Curriculum Including Lesson Plans, Activities and Bibliography.

    ERIC Educational Resources Information Center

    Murphy, Elaine M.

    This course outline suggests materials and learning activities on the interrelated causes and consequences of population growth and other population concerns. Designed to educate general college audiences, it is also intended for use as a preservice course for teachers. In addition, the course can be modified for high school students. The course…

  19. 7 CFR 981.441 - Credit for market promotion activities, including paid advertising.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGRICULTURE ALMONDS GROWN IN CALIFORNIA Administrative Rules and Regulations § 981.441 Credit for market... each activity shall be to promote the sale, consumption or use of California almonds, and nothing... in California almond growing counties with more than 1,000 bearing acres: Provided, That...

  20. 7 CFR 981.441 - Credit for market promotion activities, including paid advertising.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGRICULTURE ALMONDS GROWN IN CALIFORNIA Administrative Rules and Regulations § 981.441 Credit for market... each activity shall be to promote the sale, consumption or use of California almonds, and nothing... in California almond growing counties with more than 1,000 bearing acres: Provided, That...

  1. 7 CFR 981.441 - Credit for market promotion activities, including paid advertising.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGRICULTURE ALMONDS GROWN IN CALIFORNIA Administrative Rules and Regulations § 981.441 Credit for market... each activity shall be to promote the sale, consumption or use of California almonds, and nothing... in California almond growing counties with more than 1,000 bearing acres: Provided, That...

  2. 7 CFR 981.441 - Credit for market promotion activities, including paid advertising.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGRICULTURE ALMONDS GROWN IN CALIFORNIA Administrative Rules and Regulations § 981.441 Credit for market... each activity shall be to promote the sale, consumption or use of California almonds, and nothing... in California almond growing counties with more than 1,000 bearing acres: Provided, That...

  3. Backyards and Butterflies: Ways to Include Children with Disabilities in Outdoor Activities.

    ERIC Educational Resources Information Center

    Greenstein, Doreen; And Others

    This sourcebook is designed for children, parents, and families, detailing ideas for outdoor play and learning activities, with emphasis on involving children with disabilities in outdoor play. A rural perspective permeates the guide, although each chapter contains ideas for making outdoor environments more accessible and safer for all children,…

  4. Beyond Right or Wrong: Challenges of Including Creative Design Activities in the Classroom

    ERIC Educational Resources Information Center

    Brennan, Karen

    2015-01-01

    In this article, we explore challenges encountered by K-12 educators in establishing classroom cultures that support creative learning activities with the Scratch programming language. Providing opportunities for students to understand and to build capacities for creative work was described by many of the teachers that we interviewed as a central…

  5. Space Resources for Teachers: Biology, Including Suggestions for Classroom Activities and Laboratory Experiments.

    ERIC Educational Resources Information Center

    Lee, Tom E.; And Others

    This compilation of resource units concerns the latest developments in space biology. Some of the topics included are oxygen consumption, temperature, radiation, rhythms, weightlessness, acceleration and vibration stress, toxicity, and sensory and perceptual problems. Many of the topics are interdisciplinary and relate biology, physiology,…

  6. 7 CFR 981.441 - Credit for market promotion activities, including paid advertising.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... relations purposes, including E-commerce (mail ordering through the Internet): Provided, That Credit-Back...-Back is requested. (e) The following requirements shall apply to Credit-Back for all promotional... and Canada, paragraph (e)(5) of this section shall also apply. (2) The clear and evident purpose...

  7. In vitro bactericidal activity of aminoglycosides, including the next-generation drug plazomicin, against Brucella spp.

    PubMed

    Olsen, Steven C; Carlson, Steve A

    2015-01-01

    Plazomicin is a next-generation aminoglycoside with a potentially unique set of clinical characteristics compared with other aminoglycosides. This study assessed the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of plazomicin against 15 clinical isolates as well as three reference strains representing Brucella abortus, Brucella melitensis and Brucella suis. These data were compared with those obtained for six other aminoglycosides and two aminocyclitols. Plazomicin and gentamicin were the only drugs demonstrating bactericidal activity towards two of the three Brucella spp., whilst plazomicin was the only drug exhibiting bactericidal activity against B. suis. This is the first study to assess the bactericidal nature of plazomicin against Brucella spp. in vitro. PMID:25459738

  8. Techniques for automated local activation time annotation and conduction velocity estimation in cardiac mapping

    PubMed Central

    Cantwell, C.D.; Roney, C.H.; Ng, F.S.; Siggers, J.H.; Sherwin, S.J.; Peters, N.S.

    2015-01-01

    Measurements of cardiac conduction velocity provide valuable functional and structural insight into the initiation and perpetuation of cardiac arrhythmias, in both a clinical and laboratory context. The interpretation of activation wavefronts and their propagation can identify mechanistic properties of a broad range of electrophysiological pathologies. However, the sparsity, distribution and uncertainty of recorded data make accurate conduction velocity calculation difficult. A wide range of mathematical approaches have been proposed for addressing this challenge, often targeted towards specific data modalities, species or recording environments. Many of these algorithms require identification of activation times from electrogram recordings which themselves may have complex morphology or low signal-to-noise ratio. This paper surveys algorithms designed for identifying local activation times and computing conduction direction and speed. Their suitability for use in different recording contexts and applications is assessed. PMID:25978869

  9. Activity of faropenem tested against Neisseria gonorrhoeae isolates including fluoroquinolone-resistant strains.

    PubMed

    Jones, Ronald N; Critchley, Ian A; Whittington, William L H; Janjic, Nebojsa; Pottumarthy, Sudha

    2005-12-01

    We evaluated the anti-gonococcal potency of faropenem along with 7 comparator reference antimicrobials against a preselected collection of clinical isolates. The 265 isolates were inclusive of 2 subsets: 1) 76 well-characterized resistant phenotypes of gonococcal strains (53 quinolone-resistant strains--31 with documented quinolone resistance-determining region changes from Japan, 15 strains resistant to penicillin and tetracycline, and 8 strains with intermediate susceptibility to penicillin) and 2) 189 recent isolates from clinical specimens in 2004 from 6 states across the United States where quinolone resistance is prevalent. Activity of faropenem was adversely affected by l-cysteine hydrochloride in IsoVitaleX (4-fold increase in [minimal inhibitory concentration] MIC50; 0.06 versus 0.25 microg/mL). The rank order of potency of the antimicrobials for the entire collection was ceftriaxone (MIC90, 0.06 microg/mL) > faropenem (0.25 microg/mL) > azithromycin (0.5 microg/mL) > cefuroxime (1 microg/mL) > tetracycline (2 microg/mL) > penicillin = ciprofloxacin = levofloxacin (4 microg/mL). Using MIC90 for comparison, faropenem was 4-fold more potent than cefuroxime (0.25 versus 1 microg/mL), but was 4-fold less active than ceftriaxone (0.25 versus 0.06 microg/mL). Although the activity of faropenem was not affected by either penicillinase production (MIC90, 0.12 microg/mL, penicillinase-positive) or increasing ciprofloxacin MIC (0.25 microg/mL, ciprofloxacin-resistant), increasing penicillin MIC was associated with an increase in MIC90 values (0.016 microg/mL for penicillin-susceptible to 0.25 microg/mL for penicillin-resistant strains). Among the recent (2004) clinical gonococcal isolates tested, reduced susceptibility to penicillins, tetracycline, and fluoroquinolones was high (28.0-94.2%). Geographic distribution of the endemic resistance rates of gonococci varied considerably, with 16.7-66.7% of the gonococcal isolates being ciprofloxacin-resistant in Oregon

  10. Phytophthora infestans Has a Plethora of Phospholipase D Enzymes Including a Subclass That Has Extracellular Activity

    PubMed Central

    Meijer, Harold J. G.; Hassen, Hussen Harrun; Govers, Francine

    2011-01-01

    In eukaryotes phospholipase D (PLD) is involved in many cellular processes. Currently little is known about PLDs in oomycetes. Here we report that the oomycete plant pathogen Phytophthora infestans has a large repertoire of PLDs divided over six subfamilies: PXPH-PLD, PXTM-PLD, TM-PLD, PLD-likes, and type A and B sPLD-likes. Since the latter have signal peptides we developed a method using metabolically labelled phospholipids to monitor if P. infestans secretes PLD. In extracellular medium of ten P. infestans strains PLD activity was detected as demonstrated by the production of phosphatidic acid and the PLD specific marker phosphatidylalcohol. PMID:21423760

  11. Phytophthora infestans has a plethora of phospholipase D enzymes including a subclass that has extracellular activity.

    PubMed

    Meijer, Harold J G; Hassen, Hussen Harrun; Govers, Francine

    2011-01-01

    In eukaryotes phospholipase D (PLD) is involved in many cellular processes. Currently little is known about PLDs in oomycetes. Here we report that the oomycete plant pathogen Phytophthora infestans has a large repertoire of PLDs divided over six subfamilies: PXPH-PLD, PXTM-PLD, TM-PLD, PLD-likes, and type A and B sPLD-likes. Since the latter have signal peptides we developed a method using metabolically labelled phospholipids to monitor if P. infestans secretes PLD. In extracellular medium of ten P. infestans strains PLD activity was detected as demonstrated by the production of phosphatidic acid and the PLD specific marker phosphatidylalcohol. PMID:21423760

  12. 30 CFR 585.800 - How must I conduct my activities to comply with safety and environmental requirements?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... for Activities Conducted Under SAPs, COPs and GAPs § 585.800 How must I conduct my activities to.... (b) You must certify compliance with those terms and conditions identified in your approved SAP,...

  13. 30 CFR 585.800 - How must I conduct my activities to comply with safety and environmental requirements?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... for Activities Conducted Under SAPs, COPs and GAPs § 585.800 How must I conduct my activities to.... (b) You must certify compliance with those terms and conditions identified in your approved SAP,...

  14. 30 CFR 285.800 - How must I conduct my activities to comply with safety and environmental requirements?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Activities Conducted Under SAPs, COPs and GAPs § 285.800 How must I conduct my activities to comply with... compliance with those terms and conditions identified in your approved SAP, COP, or GAP, as required...

  15. 30 CFR 585.800 - How must I conduct my activities to comply with safety and environmental requirements?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for Activities Conducted Under SAPs, COPs and GAPs § 585.800 How must I conduct my activities to.... (b) You must certify compliance with those terms and conditions identified in your approved SAP,...

  16. A Methodology for Post Operational Clean Out of a Highly Active Facility Including Solids Behaviour - 12386

    SciTech Connect

    Edmondson, Michael J.; Ward, Tracy R.; Maxwell, Lisa J.

    2012-07-01

    The Highly Active Liquor Evaporation and Storage (HALES) plant at Sellafield handles acidic fission product containing liquor with typical activities of the order of 18x10{sup 9} Bq/ml. A strategy experimental feedback approach has been used to establish a wash regime for the Post Operational Clean Out (POCO) of the oldest storage tanks for this liquor. Two different wash reagents have been identified as being potentially suitable for removal of acid insoluble fission product precipitates. Ammonium carbamate and sodium carbonate yield similar products during the proposed wash cycle. The proposed wash reagents provide dissolution of caesium phosphomolybdate (CPM) and zirconium molybdate (ZM) solid phases but yields a fine, mobile precipitate of metal carbonates from the Highly Active Liquor (HAL) supernate. Addition of nitric acid to the wash effluent can cause CPM to precipitate where there is sufficient caesium and phosphorous available. Where they are not present (from ZM dissolution) the nitric acid addition initially produces a nitrate precipitate which then re-dissolves, along with the metal carbonates, to give a solid-free solution. The different behaviour of the two solids during the wash cycle has led to the proposal for an amended flowsheet. Additional studies on the potential to change the morphology of crystallising ZM have presented opportunities for changing the rheology of ZM sediments through doping with tellurium or particular organic acids. Two different wash reagents have been identified as being potentially suitable for the POCO of HALES Oldside HASTs. AC and SC both yield similar products during the proposed wash cycle. However, the different behaviour of the two principle HAL solids, CPM and ZM, during the wash cycle has led to the proposal for an amended flowsheet. Additional studies on the potential to change the morphology of crystallising ZM have presented opportunities for changing its rheology through doping with tellurium or certain

  17. Nuclear Rocket Test Facility Decommissioning Including Controlled Explosive Demolition of a Neutron-Activated Shield Wall

    SciTech Connect

    Michael Kruzic

    2007-09-01

    Located in Area 25 of the Nevada Test Site, the Test Cell A Facility was used in the 1960s for the testing of nuclear rocket engines, as part of the Nuclear Rocket Development Program. The facility was decontaminated and decommissioned (D&D) in 2005 using the Streamlined Approach For Environmental Restoration (SAFER) process, under the Federal Facilities Agreement and Consent Order (FFACO). Utilities and process piping were verified void of contents, hazardous materials were removed, concrete with removable contamination decontaminated, large sections mechanically demolished, and the remaining five-foot, five-inch thick radiologically-activated reinforced concrete shield wall demolished using open-air controlled explosive demolition (CED). CED of the shield wall was closely monitored and resulted in no radiological exposure or atmospheric release.

  18. LIPID PEROXIDATION GENERATES BIOLOGICALLY ACTIVE PHOSPHOLIPIDS INCLUDING OXIDATIVELY N-MODIFIED PHOSPHOLIPIDS

    PubMed Central

    Davies, Sean S.; Guo, Lilu

    2014-01-01

    Peroxidation of membranes and lipoproteins converts “inert” phospholipids into a plethora of oxidatively modified phospholipids (oxPL) that can act as signaling molecules. In this review, we will discuss four major classes of oxPL: mildly oxygenated phospholipids, phospholipids with oxidatively truncated acyl chains, phospholipids with cyclized acyl chains, and phospholipids that have been oxidatively N-modified on their headgroups by reactive lipid species. For each class of oxPL we will review the chemical mechanisms of their formation, the evidence for their formation in biological samples, the biological activities and signaling pathways associated with them, and the catabolic pathways for their elimination. We will end by briefly highlighting some of the critical questions that remain about the role of oxPL in physiology and disease. PMID:24704586

  19. Design of a high-lift experiment in water including active flow control

    NASA Astrophysics Data System (ADS)

    Beutel, T.; Sattler, S.; El Sayed, Y.; Schwerter, M.; Zander, M.; Büttgenbach, S.; Leester-Schädel, M.; Radespiel, R.; Sinapius, M.; Wierach, P.

    2014-07-01

    This paper describes the structural design of an active flow-control experiment. The aim of the experiment is to investigate the increase in efficiency of an internally blown Coanda flap using unsteady blowing. The system uses tailor-made microelectromechanical (MEMS) pressure sensors to determine the state of the oncoming flow and an actuated lip to regulate the mass flow and velocity of a stream near a wall over the internally blown flap. Sensors and actuators are integrated into a highly loaded system that is extremely compact. The sensors are connected to a bus system that feeds the data into a real-time control system. The piezoelectric actuators using the d 33 effect at a comparable low voltage of 120 V are integrated into a lip that controls the blowout slot height. The system is designed for closed-loop control that efficiently avoids flow separation on the Coanda flap. The setup is designed for water-tunnel experiments in order to reduce the free-stream velocity and the system’s control frequency by a factor of 10 compared with that in air. This paper outlines the function and verification of the system’s main components and their development.

  20. Fatty acid-releasing activities in Sinorhizobium meliloti include unusual diacylglycerol lipase

    PubMed Central

    Sahonero-Canavesi, Diana X.; Sohlenkamp, Christian; Sandoval-Calderón, Mario; Lamsa, Anne; Pogliano, Kit; López-Lara, Isabel M.; Geiger, Otto

    2016-01-01

    Summary Phospholipids are well known for their membrane forming properties and thereby delimit any cell from the exterior world. In addition, membrane phospholipids can act as precursors for signals and other biomolecules during their turnover. Little is known about phospholipid signalling, turnover and remodelling in bacteria. Recently, we showed that a FadD-deficient mutant of Sinorhizobium meliloti, unable to convert free fatty acids to their coenzyme A derivatives, accumulates free fatty acids during the stationary phase of growth. Enzymatic activities responsible for the generation of these free fatty acids were unknown in rhizobia. Searching the genome of S. meliloti, we identified a potential lysophospholipase (SMc04041) and two predicted patatin-like phospholipases A (SMc00930, SMc01003). Although SMc00930 as well as SMc01003 contribute to the release of free fatty acids in S. meliloti, neither one can use phospholipids as substrates. Here we show that SMc01003 converts diacylglycerol to monoacylglycerol and a fatty acid, and that monoacylglycerol can be further degraded by SMc01003 to another fatty acid and glycerol. A SMc01003-deficient mutant of S. meliloti transiently accumulates diacylglycerol, suggesting that SMc01003 also acts as diacylglycerol lipase (DglA) in its native background. Expression of the DglA lipase in Escherichia coli causes lysis of cells in stationary phase of growth. PMID:25711932

  1. Fatty acid-releasing activities in Sinorhizobium meliloti include unusual diacylglycerol lipase.

    PubMed

    Sahonero-Canavesi, Diana X; Sohlenkamp, Christian; Sandoval-Calderón, Mario; Lamsa, Anne; Pogliano, Kit; López-Lara, Isabel M; Geiger, Otto

    2015-09-01

    Phospholipids are well known for their membrane-forming properties and thereby delimit any cell from the exterior world. In addition, membrane phospholipids can act as precursors for signals and other biomolecules during their turnover. Little is known about phospholipid signalling, turnover and remodelling in bacteria. Recently, we showed that a FadD-deficient mutant of Sinorhizobium meliloti, unable to convert free fatty acids to their coenzyme A derivatives, accumulates free fatty acids during the stationary phase of growth. Enzymatic activities responsible for the generation of these free fatty acids were unknown in rhizobia. Searching the genome of S. meliloti, we identified a potential lysophospholipase (SMc04041) and two predicted patatin-like phospholipases A (SMc00930, SMc01003). Although SMc00930 as well as SMc01003 contribute to the release of free fatty acids in S. meliloti, neither one can use phospholipids as substrates. Here we show that SMc01003 converts diacylglycerol to monoacylglycerol and a fatty acid, and that monoacylglycerol can be further degraded by SMc01003 to another fatty acid and glycerol. A SMc01003-deficient mutant of S. meliloti transiently accumulates diacylglycerol, suggesting that SMc01003 also acts as diacylglycerol lipase (DglA) in its native background. Expression of the DglA lipase in Escherichia coli causes lysis of cells in stationary phase of growth.

  2. Modeling the development of biofilm density including active bacteria, inert biomass, and extracellular polymeric substances.

    PubMed

    Laspidou, Chrysi S; Rittmann, Bruce E

    2004-01-01

    We present the unified multi-component cellular automaton (UMCCA) model, which predicts quantitatively the development of the biofilm's composite density for three biofilm components: active bacteria, inert or dead biomass, and extracellular polymeric substances. The model also describes the concentrations of three soluble organic components (soluble substrate and two types of soluble microbial products) and oxygen. The UMCCA model is a hybrid discrete-differential mathematical model and introduces the novel feature of biofilm consolidation. Our hypothesis is that the fluid over the biofilm creates pressures and vibrations that cause the biofilm to consolidate, or pack itself to a higher density over time. Each biofilm compartment in the model output consolidates to a different degree that depends on the age of its biomass. The UMCCA model also adds a cellular automaton algorithm that identifies the path of least resistance and directly moves excess biomass along that path, thereby ensuring that the excess biomass is distributed efficiently. A companion paper illustrates the trends that the UMCCA model is able to represent and shows a comparison with experimental results. PMID:15276752

  3. Ozone control of biological activity during Earth's history, including the KT catastrophe

    NASA Technical Reports Server (NTRS)

    Sheldon, W. R.

    1994-01-01

    There have been brief periods since the beginning of the Cambrian some 600 m.y. ago when mass extinctions destroyed a significant fraction of living species. The most widely studied of these events is the catastrophe at the KT boundary that ended the long dominance of the dinosaurs. In addition to mass extinctions, there is another profound discontinuity in the history of Earth's biota, the explosion of life at the end of the Precambrian era which is an episode that is not explained well at all. For some 3 b.y. before the Cambrian, life had been present on Earth, but maintained a low level of activity which is an aspect of the biota that is puzzling, especially during the last two-thirds of that period. During the last 2 b.y. before the Cambrian, conditions at the Earth's surface were suitable for a burgeoning of the biota, according to most criteria: the oceans neither boiled nor were fozen solid during this time, and the atmosphere contained sufficient O for the development of animals. The purpose of this paper is to suggest that mass extinctions and the lackluster behavior of the Precambrian biota share a common cause: an inadequate amount of ozone in the atmosphere.

  4. Shaking stack model of ion conduction through the Ca(2+)-activated K+ channel.

    PubMed Central

    Schumaker, M F

    1992-01-01

    Motivated by the results of Neyton and Miller (1988. J. Gen. Physiol. 92:549-586), suggesting that the Ca(2+)-activated K+ channel has four high affinity ion binding sites, we propose a physically attractive variant of the single-vacancy conduction mechanism for this channel. Simple analytical expressions for conductance, current, flux ratio exponent, and reversal potential under bi-ionic conditions are found. A set of conductance data are analyzed to determine a realistic range of parameter values. Using these, we find qualitative agreement with a variety of experimental results previously reported in the literature. The exquisite selectivity of the Ca(2+)-activated K+ channel may be explained as a consequence of the concerted motion of the "stack" in the proposed mechanism. PMID:1420923

  5. Participation in Organized Activities and Conduct Problems in Elementary School: The Mediating Effect of Social Skills

    ERIC Educational Resources Information Center

    Denault, Anne-Sophie; Déry, Michèle

    2015-01-01

    The goal of this study was to test a mediation model in which social skills mediate the relationship between participation in organized activities and conduct problems among elementary school children. Two moderators of these associations were also examined, namely, gender and reception of special education services. A total of 563 children (45%…

  6. A Context-Aware Ubiquitous Learning Approach to Conducting Scientific Inquiry Activities in a Science Park

    ERIC Educational Resources Information Center

    Hwang, Gwo-Jen; Tsai, Chin-Chung; Chu, Hui-Chun; Kinshuk; Chen, Chieh-Yuan

    2012-01-01

    Fostering students' scientific inquiry competence has been recognised as being an important and challenging objective of science education. To strengthen the understanding of science theories or notations, researchers have suggested conducting some learning activities in the field via operating relevant devices. In a traditional infield scientific…

  7. 10 CFR 52.91 - Authorization to conduct limited work authorization activities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... determination required by 10 CFR 50.10(e), and the Director of New Reactors or the Director of Nuclear Reactor... activities. 52.91 Section 52.91 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.91 Authorization to conduct limited...

  8. 10 CFR 52.91 - Authorization to conduct limited work authorization activities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... determination required by 10 CFR 50.10(e), and the Director of New Reactors or the Director of Nuclear Reactor... activities. 52.91 Section 52.91 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.91 Authorization to conduct limited...

  9. 10 CFR 52.91 - Authorization to conduct limited work authorization activities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... determination required by 10 CFR 50.10(e), and the Director of New Reactors or the Director of Nuclear Reactor... activities. 52.91 Section 52.91 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.91 Authorization to conduct limited...

  10. 10 CFR 52.91 - Authorization to conduct limited work authorization activities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... determination required by 10 CFR 50.10(e), and the Director of New Reactors or the Director of Nuclear Reactor... activities. 52.91 Section 52.91 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.91 Authorization to conduct limited...

  11. 10 CFR 52.91 - Authorization to conduct limited work authorization activities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... determination required by 10 CFR 50.10(e), and the Director of New Reactors or the Director of Nuclear Reactor... activities. 52.91 Section 52.91 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.91 Authorization to conduct limited...

  12. 34 CFR 350.60 - How must a grantee conduct activities?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 2 2012-07-01 2012-07-01 false How must a grantee conduct activities? 350.60 Section 350.60 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION DISABILITY AND...

  13. 34 CFR 350.60 - How must a grantee conduct activities?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 2 2011-07-01 2010-07-01 true How must a grantee conduct activities? 350.60 Section 350.60 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION DISABILITY AND...

  14. 34 CFR 350.60 - How must a grantee conduct activities?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 2 2013-07-01 2013-07-01 false How must a grantee conduct activities? 350.60 Section 350.60 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION DISABILITY AND...

  15. 34 CFR 350.22 - What activities must a Rehabilitation Research and Training Center conduct?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 2 2012-07-01 2012-07-01 false What activities must a Rehabilitation Research and Training Center conduct? 350.22 Section 350.22 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF...

  16. 34 CFR 350.60 - How must a grantee conduct activities?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 2 2014-07-01 2013-07-01 true How must a grantee conduct activities? 350.60 Section 350.60 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION DISABILITY AND...

  17. 34 CFR 350.60 - How must a grantee conduct activities?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false How must a grantee conduct activities? 350.60 Section 350.60 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION DISABILITY AND...

  18. 34 CFR 350.22 - What activities must a Rehabilitation Research and Training Center conduct?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 2 2013-07-01 2013-07-01 false What activities must a Rehabilitation Research and Training Center conduct? 350.22 Section 350.22 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF...

  19. 34 CFR 350.22 - What activities must a Rehabilitation Research and Training Center conduct?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 2 2014-07-01 2013-07-01 true What activities must a Rehabilitation Research and Training Center conduct? 350.22 Section 350.22 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF...

  20. 30 CFR 585.1010 - How long may I conduct activities under an Alternate Use RUE?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Alternate Use RUE? 585.1010 Section 585.1010 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT... Facilities Alternate Use Rue Administration § 585.1010 How long may I conduct activities under an Alternate Use RUE? (a) We will establish on a case-by-case basis, and set forth in the Alternate Use RUE,...

  1. 30 CFR 585.1010 - How long may I conduct activities under an Alternate Use RUE?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Alternate Use RUE? 585.1010 Section 585.1010 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT... Facilities Alternate Use Rue Administration § 585.1010 How long may I conduct activities under an Alternate Use RUE? (a) We will establish on a case-by-case basis, and set forth in the Alternate Use RUE,...

  2. 30 CFR 585.1010 - How long may I conduct activities under an Alternate Use RUE?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Alternate Use RUE? 585.1010 Section 585.1010 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT... Facilities Alternate Use Rue Administration § 585.1010 How long may I conduct activities under an Alternate Use RUE? (a) We will establish on a case-by-case basis, and set forth in the Alternate Use RUE,...

  3. 30 CFR 285.1010 - How long may I conduct activities under an Alternate Use RUE?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Alternate Use RUE? 285.1010 Section 285.1010 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF... Alternate Use Rue Administration § 285.1010 How long may I conduct activities under an Alternate Use RUE? (a) We will establish on a case-by-case basis, and set forth in the Alternate Use RUE, the length of...

  4. 76 FR 50457 - Taking and Importing Marine Mammals; Military Training Activities and Research Conducted Within...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-15

    ... became effective on August 3, 2010 (75 FR 45527, August 3, 2010), and remain in effect through August 3... under regulations issued on August 3, 2010 (75 FR 45527). The Navy has complied with the measures...; Military Training Activities and Research Conducted Within the Mariana Islands Range Complex...

  5. 30 CFR 550.207 - What ancillary activities may I conduct?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What ancillary activities may I conduct? 550.207 Section 550.207 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR... cuttings discharges, projected air emissions, or potential hydrogen sulfide (H2S) releases....

  6. 30 CFR 250.207 - What ancillary activities may I conduct?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What ancillary activities may I conduct? 250.207 Section 250.207 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT... spills, drilling muds and cuttings discharges, projected air emissions, or potential hydrogen...

  7. 30 CFR 550.207 - What ancillary activities may I conduct?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What ancillary activities may I conduct? 550.207 Section 550.207 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR... cuttings discharges, projected air emissions, or potential hydrogen sulfide (H2S) releases....

  8. 30 CFR 550.207 - What ancillary activities may I conduct?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What ancillary activities may I conduct? 550.207 Section 550.207 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR... cuttings discharges, projected air emissions, or potential hydrogen sulfide (H2S) releases....

  9. Lifetime and conductance of acetylcholine-activated channels in normal and denervated toad sartorius muscle.

    PubMed Central

    Gage, P W; Hamill, O P

    1980-01-01

    1. The average lifetime and conductance of acetylcholine-activated channels were measured in normal and denervated, voltage-clamped toad sartorius muscle fibres at 10 degrees C. 2. The null potential was -4 +/- 1 mV for subsynaptic channels in normal fibres and -6 +/- 3 mV for extrasynaptic channels in denervated fibres. 3. There was a linear relationship between variance of conductance fluctuations and mean conductance for acetylcholine-induced currents up to 50 nA, in denervated fibres clamped at -50 mV. The ratio gave a channel conductance of 14 pS. 4. At the same membrane potential, the average lifetime of extrasynaptic channels in denervated fibres was approximately double, whereas channel conductance was approximately half, that of subsynaptic channels in normal fibres: there was little difference in net charge transfer through the two types of channel under similar conditions. 5. Single channel conductance increased, whereas average channel lifetime decreased, as the membrane potential became more positive (depolarized). The effect of potential on channel lifetime and conductance was more pronounced in denervated than in normal fibres. PMID:6767026

  10. Radio Properties of Low Redshift Broad Line Active Galactic Nuclei Including Multiple Component Radio Sources

    NASA Astrophysics Data System (ADS)

    Rafter, Stephen E.

    2010-01-01

    We present results on the radio properties of a low redshift (z < 0.35) sample of 8434 broad line active galactic nuclei (AGNs) from the Sloan Digital Sky Survey after correlating the optical sources with radio sources in the Faint Images of the Radio Sky at Twenty-Centimeters survey. We find that 10% of our sample has radio emission < 4" away from the optical counterpart (core-only sources), and 1% has significant extended emission that must be taken into account when calculating the total radio luminosity (multi-component sources). Association of the extended radio emission is established by the proximity to the optical source, physical connection of jets and lobes, or large scale symmetry like in classic FRIIs. From these data we find an FRI/FRII luminosity dividing line like that found by Fanaroff & Riley (1974), where we use our core-only sources as proxies for FRIs, and our multi-component sources for the FRIIs. We find a bimodal distribution for the radio loudness (R = L(radio)/L(opt)) where the lower radio luminosity core-only sources appear as a population separate from the multi-component extended sources, compared with no evidence for bimodality when just the core-only sources are used. We also find that a log(R) value of 1.75 is well suited to separate the FRIs from the FRIIs, and that the R bimodality seen here is really a manifestation of the FRI/FRII break originally found by Fanaroff & Riley (1974). We find modest trends in the radio loud fraction as a function of Eddington ratio and black hole mass, where the fraction of RL AGNs decreases with increasing Eddington ratio, and increases when the black hole mass is above 2 x 108 solar masses.

  11. Mechanisms of Electrical Activation and Conduction in the Gastrointestinal System: Lessons from Cardiac Electrophysiology

    PubMed Central

    Tse, Gary; Lai, Eric Tsz Him; Yeo, Jie Ming; Tse, Vivian; Wong, Sunny Hei

    2016-01-01

    The gastrointestinal (GI) tract is an electrically excitable organ system containing multiple cell types, which coordinate electrical activity propagating through this tract. Disruption in its normal electrophysiology is observed in a number of GI motility disorders. However, this is not well characterized and the field of GI electrophysiology is much less developed compared to the cardiac field. The aim of this article is to use the established knowledge of cardiac electrophysiology to shed light on the mechanisms of electrical activation and propagation along the GI tract, and how abnormalities in these processes lead to motility disorders and suggest better treatment options based on this improved understanding. In the first part of the article, the ionic contributions to the generation of GI slow wave and the cardiac action potential (AP) are reviewed. Propagation of these electrical signals can be described by the core conductor theory in both systems. However, specifically for the GI tract, the following unique properties are observed: changes in slow wave frequency along its length, periods of quiescence, synchronization in short distances and desynchronization over long distances. These are best described by a coupled oscillator theory. Other differences include the diminished role of gap junctions in mediating this conduction in the GI tract compared to the heart. The electrophysiology of conditions such as gastroesophageal reflux disease and gastroparesis, and functional problems such as irritable bowel syndrome are discussed in detail, with reference to ion channel abnormalities and potential therapeutic targets. A deeper understanding of the molecular basis and physiological mechanisms underlying GI motility disorders will enable the development of better diagnostic and therapeutic tools and the advancement of this field. PMID:27303305

  12. Large-Conductance Calcium-Activated Potassium Channels in Glomerulus: From Cell Signal Integration to Disease

    PubMed Central

    Tao, Jie; Lan, Zhen; Wang, Yunman; Hei, Hongya; Tian, Lulu; Pan, Wanma; Zhang, Xuemei; Peng, Wen

    2016-01-01

    Large-conductance calcium-activated potassium (BK) channels are currently considered as vital players in a variety of renal physiological processes. In podocytes, BK channels become active in response to stimuli that increase local cytosolic Ca2+, possibly secondary to activation of slit diaphragm TRPC6 channels by chemical or mechanical stimuli. Insulin increases filtration barrier permeability through mobilization of BK channels. In mesangial cells, BK channels co-expressed with β1 subunits act as a major component of the counteractive response to contraction in order to regulate glomerular filtration. This review aims to highlight recent discoveries on the localization, physiological and pathological roles of BK channels in glomerulus. PMID:27445840

  13. Large-Conductance Calcium-Activated Potassium Channels in Glomerulus: From Cell Signal Integration to Disease.

    PubMed

    Tao, Jie; Lan, Zhen; Wang, Yunman; Hei, Hongya; Tian, Lulu; Pan, Wanma; Zhang, Xuemei; Peng, Wen

    2016-01-01

    Large-conductance calcium-activated potassium (BK) channels are currently considered as vital players in a variety of renal physiological processes. In podocytes, BK channels become active in response to stimuli that increase local cytosolic Ca(2+), possibly secondary to activation of slit diaphragm TRPC6 channels by chemical or mechanical stimuli. Insulin increases filtration barrier permeability through mobilization of BK channels. In mesangial cells, BK channels co-expressed with β1 subunits act as a major component of the counteractive response to contraction in order to regulate glomerular filtration. This review aims to highlight recent discoveries on the localization, physiological and pathological roles of BK channels in glomerulus. PMID:27445840

  14. Flowable conducting particle networks in redox-active electrolytes for grid energy storage

    DOE PAGES

    Hatzell, K. B.; Boota, M.; Kumbur, E. C.; Gogotsi, Yury G.

    2015-01-09

    This paper reports a new hybrid approach toward achieving high volumetric energy and power densities in an electrochemical flow capacitor for grid energy storage. The electrochemical flow capacitor suffers from high self-discharge and low energy density because charge storage is limited to the available surface area (electric double layer charge storage). Here, we examine two carbon materials as conducting particles in a flow battery electrolyte containing the VO2+/VO2+ redox couple. Highly porous activated carbon spheres (CSs) and multi-walled carbon nanotubes (MWCNTs) are investigated as conducting particle networks that facilitate both faradaic and electric double layer charge storage. Charge storage contributionsmore » (electric double layer and faradaic) are distinguished for flow-electrodes composed of MWCNTs and activated CSs. A MWCNT flow-electrode based in a redox-active electrolyte containing the VO2+/VO2+ redox couple demonstrates 18% less self-discharge, 10 X more energy density, and 20 X greater power densities (at 20 mV s-1) than one based on a non-redox active electrolyte. Additionally, a MWCNT redox-active flow electrode demonstrates 80% capacitance retention, and >95% coulombic efficiency over 100 cycles, indicating the feasibility of utilizing conducting networks with redox chemistries for grid energy storage.« less

  15. Flowable conducting particle networks in redox-active electrolytes for grid energy storage

    SciTech Connect

    Hatzell, K. B.; Boota, M.; Kumbur, E. C.; Gogotsi, Yury G.

    2015-01-09

    This paper reports a new hybrid approach toward achieving high volumetric energy and power densities in an electrochemical flow capacitor for grid energy storage. The electrochemical flow capacitor suffers from high self-discharge and low energy density because charge storage is limited to the available surface area (electric double layer charge storage). Here, we examine two carbon materials as conducting particles in a flow battery electrolyte containing the VO2+/VO2+ redox couple. Highly porous activated carbon spheres (CSs) and multi-walled carbon nanotubes (MWCNTs) are investigated as conducting particle networks that facilitate both faradaic and electric double layer charge storage. Charge storage contributions (electric double layer and faradaic) are distinguished for flow-electrodes composed of MWCNTs and activated CSs. A MWCNT flow-electrode based in a redox-active electrolyte containing the VO2+/VO2+ redox couple demonstrates 18% less self-discharge, 10 X more energy density, and 20 X greater power densities (at 20 mV s-1) than one based on a non-redox active electrolyte. Additionally, a MWCNT redox-active flow electrode demonstrates 80% capacitance retention, and >95% coulombic efficiency over 100 cycles, indicating the feasibility of utilizing conducting networks with redox chemistries for grid energy storage.

  16. Should Physical Activity Be Included in Nutrition Education? A Comparison of Nutrition Outcomes with and without In-Class Activities

    ERIC Educational Resources Information Center

    Palmer-Keenan, Debra M.; Corda, Kirsten

    2014-01-01

    Limited-resource adults' dietary intakes and nutrition behaviors improve as a result of Expanded Food and Nutrition Education Program (EFNEP)/Supplemental Nutrition Assistance Program Education (SNAP-Ed) participation; however, physical activity education is needed for improved health. The experimental study reported here assessed if spending…

  17. Modeling activity-dependent changes of axonal spike conduction in primary afferent C-nociceptors

    PubMed Central

    Tigerholm, Jenny; Petersson, Marcus E.; Obreja, Otilia; Lampert, Angelika; Carr, Richard; Schmelz, Martin

    2013-01-01

    Action potential initiation and conduction along peripheral axons is a dynamic process that displays pronounced activity dependence. In patients with neuropathic pain, differences in the modulation of axonal conduction velocity by activity suggest that this property may provide insight into some of the pathomechanisms. To date, direct recordings of axonal membrane potential have been hampered by the small diameter of the fibers. We have therefore adopted an alternative approach to examine the basis of activity-dependent changes in axonal conduction by constructing a comprehensive mathematical model of human cutaneous C-fibers. Our model reproduced axonal spike propagation at a velocity of 0.69 m/s commensurate with recordings from human C-nociceptors. Activity-dependent slowing (ADS) of axonal propagation velocity was adequately simulated by the model. Interestingly, the property most readily associated with ADS was an increase in the concentration of intra-axonal sodium. This affected the driving potential of sodium currents, thereby producing latency changes comparable to those observed for experimental ADS. The model also adequately reproduced post-action potential excitability changes (i.e., recovery cycles) observed in vivo. We performed a series of control experiments replicating blockade of particular ion channels as well as changing temperature and extracellular ion concentrations. In the absence of direct experimental approaches, the model allows specific hypotheses to be formulated regarding the mechanisms underlying activity-dependent changes in C-fiber conduction. Because ADS might functionally act as a negative feedback to limit trains of nociceptor activity, we envisage that identifying its mechanisms may also direct efforts aimed at alleviating neuronal hyperexcitability in pain patients. PMID:24371290

  18. Development of an oregano-based ointment with anti-microbial activity including activity against methicillin-resistant Staphlococcus aureus.

    PubMed

    Eng, William; Norman, Robert

    2010-04-01

    Increasing antibiotic resistance has prompted a search for new compounds with anti-microbial activity. In the authors' previous study, oregano extract was identified as one of the most potent anti-microbial compounds. The disk diffusion method was employed to assess the degree of inhibition against various microorganisms, and the bacteriostatic or bactericidal mechanism of action. Disk diffusion studies showed that oregano was found to be bacteriostatic for Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus, (MRSA) but bacteriocidal for seven other microorganisms. Pseudomonas aeruginosa could not be inhibited by oregano. An ointment consisting of 1-10% oregano could inhibit most organisms except for Proteus mirabilis and Proteus vulgaris, which required 20% and Pseudomonas which could not be inhibited even at the highest concentration of 80%. Oregano extracts can be formulated into an ointment that shows broad antimicrobial activity. Additional testing to assess tissue toxicity and other adverse reactions would be needed prior to human testing.

  19. Low-Temperature Curable Photo-Active Anisotropic Conductive Films (PA-ACFs)

    NASA Astrophysics Data System (ADS)

    Kim, Il; Paik, Kyung-Wook

    2014-09-01

    Photo-active anisotropic conductive films (PA-ACFs) with curing temperatures below 120°C were introduced using photo-active curing agents. The PA-ACFs showed no curing before UV activation, and the crosslinking systems of the PA-ACFs were not activated under fluorescent light exposure. However, after UV activation, the PA-ACFs were completely cured at 120°C within 10 s. Flex-on-board (FOB) assembly using PA-ACFs had adhesion strength and joint resistances similar to those of the FOB assemblies using conventional epoxy-based ACFs. This study demonstrates that PA-ACFs provide reliable interconnection and minimal thermal deformation among all the commercially available ACFs, especially for low T g substrate applications.

  20. Arecoline inhibits intermediate-conductance calcium-activated potassium channels in human glioblastoma cell lines.

    PubMed

    So, Edmund Cheung; Huang, Yan-Ming; Hsing, Chung-Hsi; Liao, Yu-Kai; Wu, Sheng-Nan

    2015-07-01

    Arecoline (ARE) is an alkaloid-type natural product from areca nut. This compound has numerous pharmacological and toxicological effects. Whether this agent interacts with ion channels to perturb functional activity of cells remains unknown. The effects of ARE on ionic currents were studied in glioma cell lines (U373 and U87MG) using patch-clamp technique. Like TRAM-34(1-[(2-chlorophenyl)-diphenylmethyl]pyrazole), ARE suppressed the amplitude of whole-cell voltage-gated K(+) currents in U373 cells elicited by a ramp voltage clamp. In cell-attached configuration, ARE did not modify the single-channel conductance of intermediate-conductance Ca(2+)-activated K(+) (IKCa) channels; however, it did reduce channel activity. Its inhibition of IKCa channels was accompanied by a significant lengthening in the slow component of mean closed time of IKCa channels. Based on minimal kinetic scheme, the dissociation constant (KD) required for ARE-mediated prolongation of mean closed time was 11.2µM. ARE-induced inhibition of IKCa channels was voltage-dependent. Inability of ARE to perturb the activity of large-conductance Ca(2+)-activated K(+) (BKCa) channels was seen. Under current-clamp recordings, ARE depolarized the membrane of U373 cells and DCEBIO reversed ARE-induced depolarization. Similarly, ARE suppressed IKCa-channel activities in oral keratinocytes. This study provides the evidence that ARE block IKCa channels in a concentration, voltage and state-dependent manner. ARE-induced block of IKCa channels is unrelated to the binding of muscarinic receptors. The effects of ARE on these channels may partially be responsible for the underlying cellular mechanisms by which it influences the functional activities of glioma cells or oral keratinocytes, if similar findings occur in vivo.

  1. How Phosphorylation and ATPase Activity Regulate Anion Flux though the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR).

    PubMed

    Zwick, Matthias; Esposito, Cinzia; Hellstern, Manuel; Seelig, Anna

    2016-07-01

    The cystic fibrosis transmembrane conductance regulator (CFTR, ABCC7), mutations of which cause cystic fibrosis, belongs to the ATP-binding cassette (ABC) transporter family and works as a channel for small anions, such as chloride and bicarbonate. Anion channel activity is known to depend on phosphorylation by cAMP-dependent protein kinase A (PKA) and CFTR-ATPase activity. Whereas anion channel activity has been extensively investigated, phosphorylation and CFTR-ATPase activity are still poorly understood. Here, we show that the two processes can be measured in a label-free and non-invasive manner in real time in live cells, stably transfected with CFTR. This study reveals three key findings. (i) The major contribution (≥90%) to the total CFTR-related ATP hydrolysis rate is due to phosphorylation by PKA and the minor contribution (≤10%) to CFTR-ATPase activity. (ii) The mutant CFTR-E1371S that is still conductive, but defective in ATP hydrolysis, is not phosphorylated, suggesting that phosphorylation requires a functional nucleotide binding domain and occurs in the post-hydrolysis transition state. (iii) CFTR-ATPase activity is inversely related to CFTR anion flux. The present data are consistent with a model in which CFTR is in a closed conformation with two ATPs bound. The open conformation is induced by ATP hydrolysis and corresponds to the post-hydrolysis transition state that is stabilized by phosphorylation and binding of chloride channel potentiators. PMID:27226582

  2. Helmet-mounted display and associated research activities recently conducted by the NASA Johnson Space Center

    NASA Astrophysics Data System (ADS)

    Marmolejo, Jose A.

    1994-06-01

    To enhance manned extravehicular activity (EVA) utilizing an extravehicular mobility unit (EMU)(i.e., a space suit and portable life support backpack), NASA has conducted research into implementing helmet mounted display (HMD) and related technology within its next generation of space suits. The NASA/Johnson Space Center has completed four feasibility development programs for the design and development of an EMU HMD, each resulting in the delivery of a binocular or biocular HMD breadboard unit utilizing conventional optical elements (i.e., glass lenses and beamsplitters) and/or holographic optics. Additional research into combining the use of voice recognition for astronaut 'hands- free' access to information via the HMD has also been conducted. Research conducted since 1983 will be summarized along with current shuttle EMU display enhancements. In addition, recommendations for the design of the next generation of displays for use within the EMU will be presented.

  3. Thermally activated conductivity of Si hybrid structure based on ZnPc thin film

    NASA Astrophysics Data System (ADS)

    Soylu, M.; Al-Ghamdi, Ahmed A.; Yakuphanoglu, F.

    2016-10-01

    In this study, an analysis of temperature-dependent electrical characteristics of ZnPc/p-Si structure has been presented. Conduction mechanisms that are accounted for the organic/inorganic devices are evaluated. At low forward voltage, current-voltage ( I- V) characteristics show ohmic behavior, limiting extraction of holes from p-Si over the ZnPc/p-Si heterojunction. Thermally activated conduction mechanism appears to be space-charge-limited conduction mechanism, taking into account the presence of an exponential trap distribution with total concentration of traps, N t of 5.77 × 1025 m-3. The series resistance is found to be temperature dependent. There is a critical point on the regime of series resistance at 200 K. The capacitance varies with temperature at different rates below and above room temperature, indicating a variation in the dielectric constant.

  4. Making Glasses Conduct: Electrochemical Doping of Redox-Active Polymer Thin Films

    NASA Astrophysics Data System (ADS)

    Boudouris, Bryan

    Optoelectronically-active macromolecules have been established as promising materials in myriad organic electronic applications (e.g., organic field-effect transistors (OFETs) and organic photovoltaic (OPV) devices). To date, however, the majority of the work surrounding these materials has focused on materials with a great deal of conjugation along their macromolecular backbones and with varying degrees of crystalline structure. Here, we describe an emerging class of macromolecular charge conductors, radical polymers, that: (1) do not contain conjugation and (2) are completely amorphous glasses. Radical polymers contain non-conjugated macromolecular backbones and stable radical sites along the side chains of the electronically-active materials. In contrast to conjugated polymer systems, these materials conduct charge in the solid state through oxidation-reduction (redox) reactions along these pendant groups. Specifically, we demonstrate that controlling the chemical functionality of the pendant groups and the molecular mobility of the macromolecular backbones significantly impacts the charge transport ability of the pristine (i.e., not doped) radical polymers species. Through proper control of these crucial parameters, we show that radical polymers can have electrical conductivity and charge mobility values on par with commonly-used conjugated polymers. Importantly, we also highlight the ability to dope radical polymers with redox-active small molecule species. This doping, in turn, increases the electrical conductivity of the glassy radical polymer thin films in a manner akin to what is observed in traditional conjugated polymer systems. In this way, we establish a means by which to fabricate optically-transparent and colorless thin film glasses capable of conducting charge in a rather rapid manner. We anticipate that these fundamental insights will prove crucial in developing new transparent conducting layers for future electronic applications.

  5. A microacoustic analysis including viscosity and thermal conductivity to model the effect of the protective cap on the acoustic response of a MEMS microphone

    PubMed Central

    Homentcovschi, D.; Miles, R. N.; Loeppert, P. V.; Zuckerwar, A. J.

    2013-01-01

    An analysis is presented of the effect of the protective cover on the acoustic response of a miniature silicon microphone. The microphone diaphragm is contained within a small rectangular enclosure and the sound enters through a small hole in the enclosure's top surface. A numerical model is presented to predict the variation in the sound field with position within the enclosure. An objective of this study is to determine up to which frequency the pressure distribution remains sufficiently uniform so that a pressure calibration can be made in free space. The secondary motivation for this effort is to facilitate microphone design by providing a means of predicting how the placement of the microphone diaphragm in the package affects the sensitivity and frequency response. While the size of the package is typically small relative to the wavelength of the sounds of interest, because the dimensions of the package are on the order of the thickness of the viscous boundary layer, viscosity can significantly affect the distribution of sound pressure around the diaphragm. In addition to the need to consider viscous effects, it is shown here that one must also carefully account for thermal conductivity to properly represent energy dissipation at the system's primary acoustic resonance frequency. The sound field is calculated using a solution of the linearized system consisting of continuity equation, Navier-Stokes equations, the state equation and the energy equation using a finite element approach. The predicted spatial variation of both the amplitude and phase of the sound pressure is shown over the range of audible frequencies. Excellent agreement is shown between the predicted and measured effects of the package on the microphone's sensitivity. PMID:24701031

  6. Highly stable redox-active molecular layers by covalent grafting to conductive diamond.

    PubMed

    Ruther, Rose E; Rigsby, Matthew L; Gerken, James B; Hogendoorn, Stephanie R; Landis, Elizabeth C; Stahl, Shannon S; Hamers, Robert J

    2011-04-20

    We demonstrate a modular "click"-based functionalization scheme that allows inexpensive conductive diamond samples to serve as an ultrastable platform for surface-tethered electrochemically active molecules stable out to ∼1.3 V vs Ag/AgCl. We have cycled surface-tethered Ru(tpy)(2) to this potential more than 1 million times with little or no degradation in propylene carbonate and only slightly reduced stability in water and acetonitrile. PMID:21438578

  7. Electrical conductivity of activated carbon-metal oxide nanocomposites under compression: a comparison study.

    PubMed

    Barroso-Bogeat, A; Alexandre-Franco, M; Fernández-González, C; Macías-García, A; Gómez-Serrano, V

    2014-12-01

    From a granular commercial activated carbon (AC) and six metal oxide (Al2O3, Fe2O3, SnO2, TiO2, WO3 and ZnO) precursors, two series of AC-metal oxide nanocomposites were prepared by wet impregnation, oven-drying at 120 °C, and subsequent heat treatment at 200 or 850 °C in an inert atmosphere. Here, the electrical conductivity of the resulting products was studied under moderate compression. The influence of the applied pressure, sample volume, mechanical work, and density of the hybrid materials was thoroughly investigated. The DC electrical conductivity of the compressed samples was measured at room temperature by the four-probe method. Compaction assays suggest that the mechanical properties of the nanocomposites are largely determined by the carbon matrix. Both the decrease in volume and the increase in density were relatively small and only significant at pressures lower than 100 kPa for AC and most nanocomposites. In contrast, the bulk electrical conductivity of the hybrid materials was strongly influenced by the intrinsic conductivity, mean crystallite size, content and chemical nature of the supported phases, which ultimately depend on the metal oxide precursor and heat treatment temperature. The supported nanoparticles may be considered to act as electrical switches either hindering or favouring the effective electron transport between the AC cores of neighbouring composite particles in contact under compression. Conductivity values as a rule were lower for the nanocomposites than for the raw AC, all of them falling in the range of semiconductor materials. With the increase in heat treatment temperature, the trend is toward the improvement of conductivity due to the increase in the crystallite size and, in some cases, to the formation of metals in the elemental state and even metal carbides. The patterns of variation of the electrical conductivity with pressure and mechanical work were slightly similar, thus suggesting the predominance of the pressure

  8. Directory of International and Regional Organizations Conducting Standards-Related Activities, May 1989

    NASA Astrophysics Data System (ADS)

    Breitenberg, Maureen

    1989-05-01

    The directory contains information on 338 international and regional organizations which conduct standardization, certification, laboratory accreditation, or other standards-related activities. The volume describes their work in these areas, the scope of each organization, national affliations of members, U.S. participants, restrictions on membership, as well as the availability of any standards in English. The volume is designed to serve the needs of Federal agencies and standards writers for information on international and regional organizations involved in standardization and related activities. It may also be useful to manufacturers, engineers, purchasing agents, and others.

  9. Synthesis, characterization and antimicrobial activity of biodegradable conducting polypyrrole-graft-chitosan copolymer

    NASA Astrophysics Data System (ADS)

    Cabuk, Mehmet; Alan, Yusuf; Yavuz, Mustafa; Unal, Halil Ibrahim

    2014-11-01

    In this study, polypyrrole-graft-chitosan (PPy-g-CS) copolymer was chemically synthesized and its structural and morphological properties characterized by FTIR, UV-vis, SEM, XRD, TGA and zeta-potential techniques. The results revealed that there were strong interactions between PPy and CS chains. The electrical conductivity of CS increased to semiconducting range by grafting. The crystallinity and thermal stability of PPy-g-CS copolymer improved when compared to CS. The copolymer was tested against various bacterial and fungal strains at various concentrations and results obtained were compared with the reference antibiotics. The results indicated that the antibacterial activity of PPy-g-CS copolymer was stronger than CS and PPy alone. The antibacterial activity of the PPy-g-CS copolymer observed to increase with rising concentration, and showed stronger activity against bacteria than Penicillin (10 mg), Rifampicin (5 mg) and Trimethoprim (25 mg), whereas showed equipotent activity with Amikacin (30 mg) and Erythromycin (15 mg) antibiotics.

  10. Graded boosting of synaptic signals by low-threshold voltage-activated calcium conductance

    PubMed Central

    Carbó Tano, Martín; Vilarchao, María Eugenia

    2015-01-01

    Low-threshold voltage-activated calcium conductances (LT-VACCs) play a substantial role in shaping the electrophysiological attributes of neurites. We have investigated how these conductances affect synaptic integration in a premotor nonspiking (NS) neuron of the leech nervous system. These cells exhibit an extensive neuritic tree, do not fire Na+-dependent spikes, but express an LT-VACC that was sensitive to 250 μM Ni2+ and 100 μM NNC 55-0396 (NNC). NS neurons responded to excitation of mechanosensory pressure neurons with depolarizing responses for which amplitude was a linear function of the presynaptic firing frequency. NNC decreased these synaptic responses and abolished the concomitant widespread Ca2+ signals. Coherent with the interpretation that the LT-VACC amplified signals at the postsynaptic level, this conductance also amplified the responses of NS neurons to direct injection of sinusoidal current. Synaptic amplification thus is achieved via a positive feedback in which depolarizing signals activate an LT-VACC that, in turn, boosts these signals. The wide distribution of LT-VACC could support the active propagation of depolarizing signals, turning the complex NS neuritic tree into a relatively compact electrical compartment. PMID:25972583

  11. Active control of near-field coupling in conductively coupled microelectromechanical system metamaterial devices

    NASA Astrophysics Data System (ADS)

    Pitchappa, Prakash; Manjappa, Manukumara; Ho, Chong Pei; Qian, You; Singh, Ranjan; Singh, Navab; Lee, Chengkuo

    2016-03-01

    We experimentally report a structurally reconfigurable metamaterial for active switching of near-field coupling in conductively coupled, orthogonally twisted split ring resonators (SRRs) operating in the terahertz spectral region. Out-of-plane reconfigurable microcantilevers integrated into the dark SRR geometry are used to provide active frequency tuning of dark SRR resonance. The geometrical parameters of individual SRRs are designed to have identical inductive-capacitive resonant frequency. This allows for the excitation of classical analogue of electromagnetically induced transparency (EIT) due to the strong conductive coupling between the SRRs. When the microcantilevers are curved up, the resonant frequency of dark SRR blue-shifts and the EIT peak is completely modulated while the SRRs are still conductively connected. EIT modulation contrast of ˜50% is experimentally achieved with actively switchable group delay of ˜2.5 ps. Electrical control, miniaturized size, and readily integrable fabrication process of the proposed structurally reconfigurable metamaterial make it an ideal candidate for the realization of various terahertz communication devices such as electrically controllable terahertz delay lines, buffers, and tunable data-rate channels.

  12. Novel conductive polypyrrole/zinc oxide/chitosan bionanocomposite: synthesis, characterization, antioxidant, and antibacterial activities.

    PubMed

    Ebrahimiasl, Saeideh; Zakaria, Azmi; Kassim, Anuar; Basri, Sri Norleha

    2015-01-01

    An antibacterial and conductive bionanocomposite (BNC) film consisting of polypyrrole (Ppy), zinc oxide (ZnO) nanoparticles (NPs), and chitosan (CS) was electrochemically synthesized on indium tin oxide (ITO) glass substrate by electrooxidation of 0.1 M pyrrole in aqueous solution containing appropriate amounts of ZnO NPs uniformly dispersed in CS. This method enables the room temperature electrosynthesis of BNC film consisting of ZnO NPs incorporated within the growing Ppy/CS composite. The morphology of Ppy/ZnO/CS BNC was characterized by scanning electron microscopy. ITO-Ppy/CS and ITO-Ppy/ZnO/CS bioelectrodes were characterized using the Fourier transform infrared technique, X-ray diffraction, and thermogravimetric analysis. The electrical conductivity of nanocomposites was investigated by a four-probe method. The prepared nanocomposites were analyzed for antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl assay. The results demonstrated that the antioxidant activity of nanocomposites increased remarkably by addition of ZnO NPs. The electrical conductivity of films showed a sudden decrease for lower weight ratios of ZnO NPs (5 wt%), while it was increased gradually for higher ratios (10, 15, and 20 wt%). The nanocomposites were analyzed for antibacterial activity against Gram-positive and Gram-negative bacteria. The results indicated that the synthesized BNC is effective against all of the studied bacteria, and its effectiveness is higher for Pseudomonas aeruginosa. The thermal stability and physical properties of BNC films were increased by an increase in the weight ratio of ZnO NPs, promising novel applications for the electrically conductive polysaccharide-based nanocomposites, particularly those that may exploit the antimicrobial nature of Ppy/ZnO/CS BNCs. PMID:25565815

  13. Novel conductive polypyrrole/zinc oxide/chitosan bionanocomposite: synthesis, characterization, antioxidant, and antibacterial activities.

    PubMed

    Ebrahimiasl, Saeideh; Zakaria, Azmi; Kassim, Anuar; Basri, Sri Norleha

    2015-01-01

    An antibacterial and conductive bionanocomposite (BNC) film consisting of polypyrrole (Ppy), zinc oxide (ZnO) nanoparticles (NPs), and chitosan (CS) was electrochemically synthesized on indium tin oxide (ITO) glass substrate by electrooxidation of 0.1 M pyrrole in aqueous solution containing appropriate amounts of ZnO NPs uniformly dispersed in CS. This method enables the room temperature electrosynthesis of BNC film consisting of ZnO NPs incorporated within the growing Ppy/CS composite. The morphology of Ppy/ZnO/CS BNC was characterized by scanning electron microscopy. ITO-Ppy/CS and ITO-Ppy/ZnO/CS bioelectrodes were characterized using the Fourier transform infrared technique, X-ray diffraction, and thermogravimetric analysis. The electrical conductivity of nanocomposites was investigated by a four-probe method. The prepared nanocomposites were analyzed for antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl assay. The results demonstrated that the antioxidant activity of nanocomposites increased remarkably by addition of ZnO NPs. The electrical conductivity of films showed a sudden decrease for lower weight ratios of ZnO NPs (5 wt%), while it was increased gradually for higher ratios (10, 15, and 20 wt%). The nanocomposites were analyzed for antibacterial activity against Gram-positive and Gram-negative bacteria. The results indicated that the synthesized BNC is effective against all of the studied bacteria, and its effectiveness is higher for Pseudomonas aeruginosa. The thermal stability and physical properties of BNC films were increased by an increase in the weight ratio of ZnO NPs, promising novel applications for the electrically conductive polysaccharide-based nanocomposites, particularly those that may exploit the antimicrobial nature of Ppy/ZnO/CS BNCs.

  14. Novel conductive polypyrrole/zinc oxide/chitosan bionanocomposite: synthesis, characterization, antioxidant, and antibacterial activities

    PubMed Central

    Ebrahimiasl, Saeideh; Zakaria, Azmi; Kassim, Anuar; Basri, Sri Norleha

    2015-01-01

    An antibacterial and conductive bionanocomposite (BNC) film consisting of polypyrrole (Ppy), zinc oxide (ZnO) nanoparticles (NPs), and chitosan (CS) was electrochemically synthesized on indium tin oxide (ITO) glass substrate by electrooxidation of 0.1 M pyrrole in aqueous solution containing appropriate amounts of ZnO NPs uniformly dispersed in CS. This method enables the room temperature electrosynthesis of BNC film consisting of ZnO NPs incorporated within the growing Ppy/CS composite. The morphology of Ppy/ZnO/CS BNC was characterized by scanning electron microscopy. ITO–Ppy/CS and ITO–Ppy/ZnO/CS bioelectrodes were characterized using the Fourier transform infrared technique, X-ray diffraction, and thermogravimetric analysis. The electrical conductivity of nanocomposites was investigated by a four-probe method. The prepared nanocomposites were analyzed for antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl assay. The results demonstrated that the antioxidant activity of nanocomposites increased remarkably by addition of ZnO NPs. The electrical conductivity of films showed a sudden decrease for lower weight ratios of ZnO NPs (5 wt%), while it was increased gradually for higher ratios (10, 15, and 20 wt%). The nanocomposites were analyzed for antibacterial activity against Gram-positive and Gram-negative bacteria. The results indicated that the synthesized BNC is effective against all of the studied bacteria, and its effectiveness is higher for Pseudomonas aeruginosa. The thermal stability and physical properties of BNC films were increased by an increase in the weight ratio of ZnO NPs, promising novel applications for the electrically conductive polysaccharide-based nanocomposites, particularly those that may exploit the antimicrobial nature of Ppy/ZnO/CS BNCs. PMID:25565815

  15. 25 CFR 170.623 - How are IRR Program projects and activities included in a self-governance agreement?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... other information required under 25 CFR 1000 subpart K. ... self-governance agreement? 170.623 Section 170.623 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE... self-governance agreement? To include an IRR Program project or activity in a self-governance...

  16. 25 CFR 170.623 - How are IRR Program projects and activities included in a self-governance agreement?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... other information required under 25 CFR 1000 subpart K. ... self-governance agreement? 170.623 Section 170.623 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE... self-governance agreement? To include an IRR Program project or activity in a self-governance...

  17. 25 CFR 170.623 - How are IRR Program projects and activities included in a self-governance agreement?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... other information required under 25 CFR 1000 subpart K. ... self-governance agreement? 170.623 Section 170.623 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE... self-governance agreement? To include an IRR Program project or activity in a self-governance...

  18. 25 CFR 170.623 - How are IRR Program projects and activities included in a self-governance agreement?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... other information required under 25 CFR 1000 subpart K. ... self-governance agreement? 170.623 Section 170.623 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE... self-governance agreement? To include an IRR Program project or activity in a self-governance...

  19. 25 CFR 170.623 - How are IRR Program projects and activities included in a self-governance agreement?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... other information required under 25 CFR 1000 subpart K. ... self-governance agreement? 170.623 Section 170.623 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE... self-governance agreement? To include an IRR Program project or activity in a self-governance...

  20. A lipid chemotactic factor from anaerobic coryneform bacteria including Corynebacterium parvum with activity for macrophages and monocytes.

    PubMed Central

    Russell, R J; McInroy, R J; Wilkinson, P C; White, R G

    1976-01-01

    A lipid with chemoattractant (chemotactic) activity for mouse and guinea-pig macrophages and for human blood monocytes is released by anaerobic coryneform bacteria (including Corynebacterium parvum). The active lipid is associated with fibrillar structures which lie on the outside of the bacterial cell and are released spontaneously during growth. The lipid can also be extracted easily by a number of methods. The fibrils are loosely associated with a capsule-like structure composed largely of polysaccharide. Purification of the active lipid was achieved by chloroform-methanol extraction of the whole organisms yielding a chloroform-soluble fraction attracting mononuclear phagocytes at concentrations around 10 microgram/ml. The infra-red spectrum of this material showed lipid but no peptide or sugar. Thin-layer chromatography yielded twelve spots of which three had chemoattractant properties. The most active of these gave staining reactions consistent with the presence of phospholipid, the other two probably contained free fatty acids and triglycerides. Thin-layer electrophoresis also yielded an active phosphorus-containing spot. Saturated fatty acids of chain lengths found in the anaerobic coryne forms had weak monocyte-attractant activity. As the active material was progressively purified, its activity as a monocyte attractant weakened. Images Figure 2 Figure 3 Figure 4 PMID:1027716

  1. Computational Study of Subdural Cortical Stimulation: Effects of Simulating Anisotropic Conductivity on Activation of Cortical Neurons

    PubMed Central

    Seo, Hyeon; Kim, Donghyeon; Jun, Sung Chan

    2015-01-01

    Subdural cortical stimulation (SuCS) is an appealing method in the treatment of neurological disorders, and computational modeling studies of SuCS have been applied to determine the optimal design for electrotherapy. To achieve a better understanding of computational modeling on the stimulation effects of SuCS, the influence of anisotropic white matter conductivity on the activation of cortical neurons was investigated in a realistic head model. In this paper, we constructed pyramidal neuronal models (layers 3 and 5) that showed primary excitation of the corticospinal tract, and an anatomically realistic head model reflecting complex brain geometry. The anisotropic information was acquired from diffusion tensor magnetic resonance imaging (DT-MRI) and then applied to the white matter at various ratios of anisotropic conductivity. First, we compared the isotropic and anisotropic models; compared to the isotropic model, the anisotropic model showed that neurons were activated in the deeper bank during cathodal stimulation and in the wider crown during anodal stimulation. Second, several popular anisotropic principles were adapted to investigate the effects of variations in anisotropic information. We observed that excitation thresholds varied with anisotropic principles, especially with anodal stimulation. Overall, incorporating anisotropic conductivity into the anatomically realistic head model is critical for accurate estimation of neuronal responses; however, caution should be used in the selection of anisotropic information. PMID:26057524

  2. ZnO:H indium-free transparent conductive electrodes for active-matrix display applications

    NASA Astrophysics Data System (ADS)

    Chen, Shuming; Wang, Sisi

    2014-12-01

    Transparent conductive electrodes based on hydrogen (H)-doped zinc oxide (ZnO) have been proposed for active-matrix (AM) display applications. When fabricated with optimal H plasma power and optimal plasma treatment time, the resulting ZnO:H films exhibit low sheet resistance of 200 Ω/◻ and high average transmission of 85% at a film thickness of 150 nm. The demonstrated transparent conductive ZnO:H films can potentially replace indium-tin-oxide and serve as pixel electrodes for organic light-emitting diodes as well as source/drain electrodes for ZnO-based thin-film transistors. Use of the proposed ZnO:H electrodes means that two photomask stages can be removed from the fabrication process flow for ZnO-based AM backplanes.

  3. Sensing performance of electrically conductive fabrics and dielectric electro active polymers for parachutes

    NASA Astrophysics Data System (ADS)

    Favini, Eric; Niezrecki, Christopher; Manohar, Sanjeev K.; Willis, David; Chen, Julie; Niemi, Eugene; Desabrais, Kenneth; Charette, Christine

    2011-04-01

    This paper quantifies the sensing capabilities of novel smart materials in an effort to improve the performance, better understand the physics, and enhance the safety of parachutes. Based upon a recent review of actuation technologies for parachute applications, it was surmised that the actuators reviewed could not be used to effectively alter the drag or lift (i.e. geometry, porosity, or air vent openings) of a parachute during flight. However, several materials showed potential for sensing applications within a parachute, specifically electrically conductive fabrics and dielectric electro-active polymers. This paper introduces several new conductive fabrics and provides an evaluation of the sensing performance of these smart materials based upon test results using mechanical testing and digital image correlation for comparison.

  4. Effect of conductive additives to gel electrolytes on activated carbon-based supercapacitors

    NASA Astrophysics Data System (ADS)

    Barzegar, Farshad; Dangbegnon, Julien K.; Bello, Abdulhakeem; Momodu, Damilola Y.; Johnson, A. T. Charlie; Manyala, Ncholu

    2015-09-01

    This article is focused on polymer based gel electrolyte due to the fact that polymers are cheap and can be used to achieve extended potential window for improved energy density of the supercapacitor devices when compared to aqueous electrolytes. Electrochemical characterization of a symmetric supercapacitor devices based on activated carbon in different polyvinyl alcohol (PVA) based gel electrolytes was carried out. The device exhibited a maximum energy density of 24 Wh kg-1 when carbon black was added to the gel electrolyte as conductive additive. The good energy density was correlated with the improved conductivity of the electrolyte medium which is favorable for fast ion transport in this relatively viscous environment. Most importantly, the device remained stable with no capacitance lost after 10,000 cycles.

  5. ZnO:H indium-free transparent conductive electrodes for active-matrix display applications

    SciTech Connect

    Chen, Shuming Wang, Sisi

    2014-12-01

    Transparent conductive electrodes based on hydrogen (H)-doped zinc oxide (ZnO) have been proposed for active-matrix (AM) display applications. When fabricated with optimal H plasma power and optimal plasma treatment time, the resulting ZnO:H films exhibit low sheet resistance of 200 Ω/◻ and high average transmission of 85% at a film thickness of 150 nm. The demonstrated transparent conductive ZnO:H films can potentially replace indium-tin-oxide and serve as pixel electrodes for organic light-emitting diodes as well as source/drain electrodes for ZnO-based thin-film transistors. Use of the proposed ZnO:H electrodes means that two photomask stages can be removed from the fabrication process flow for ZnO-based AM backplanes.

  6. Electrically conductive PVC layers filled with active carbon containing H+-conducting porous structures of sulfuric acid complexes of cyclams on fabrics

    NASA Astrophysics Data System (ADS)

    Tsivadze, A. Yu.; Fridman, A. Ya.; Morozova, E. M.; Sokolova, N. P.; Voloshchuk, A. M.; Petukhova, G. A.; Bardyshev, I. I.; Gorbunov, A. M.; Novikov, A. K.; Polyakova, I. Ya.; Titova, V. N.; Yavich, A. A.; Petrova, N. V.; Krasil'nikova, O. K.

    2015-07-01

    Electrically conductive PVC layers are synthesized. The layers are filled with active carbons containing porous H+-conductive structures of hydroxyethylcyclam/sulfuric acid complexes crosslinked with cellulose fabric. They are interlaid with layers based on the same structures containing added benzene and hexane adsorbates and solvates. It is found that upon anode or cathode polarization of the layers as H+-conductive electrochemical bridges in air and in the vapor and liquid phases of benzene and hexane, either the electroreduction of H+ to H2 or the electrooxidation of H2O to O2 occurs in the areas of contact between active carbon particles and the complexes. The dependences of rates of H2 and O2 formation on the voltage are studied. The magnitudes of overvoltage and the constants of electrochemical reactions are found to depend on the composition of a layer.

  7. Transient conduction-radiation analysis of an absolute active cavity radiometer using finite elements

    NASA Technical Reports Server (NTRS)

    Mahan, J. R.; Kowsary, F.; Tira, N.; Gardiner, B. D.

    1987-01-01

    A NASA-developed finite element-based model of a generic active cavity radiometer (ACR) has been developed in order to study the dependence on operating temperature of the closed-loop and open-loop transient response of the instrument. Transient conduction within the sensing element is explored, and the transient temperature distribution resulting from the application of a time-varying radiative boundary condition is calculated. The results verify the prediction that operation of an ACR at cryogenic temperatures results in large gains in frequency response.

  8. Hippocampal glucocorticoid receptor activation enhances voltage-dependent Ca2+ conductances: relevance to brain aging.

    PubMed Central

    Kerr, D S; Campbell, L W; Thibault, O; Landfield, P W

    1992-01-01

    Glucocorticoids (GCs) activate several biochemical/molecular processes in the hippocampus through two receptor types. In addition, GCs influence cognitive behaviors and hippocampal neural activity and can also increase the rate of aging-dependent cell loss in the hippocampus. However, the ionic mechanisms through which GCs modulate hippocampal neuronal function are not well understood. We report here direct evidence that activation of cytosolic steroid receptors, specifically of the type II GC receptor, can enhance voltage-dependent Ca2+ conductances in brain neurons. Ca2+ current was assessed by current-clamp measures of Ca2+ action potentials and by sharp electrode voltage-clamp analyses of voltage-sensitive currents in cesium-, tetrodotoxin-, and tetraethylammonium-treated CA1 neurons in hippocampal slices. Both Ca2+ action potentials and voltage-activated Ca2+ currents (N- and L-like) were increased by 2-hr exposure to the synthetic GC receptor agonist, RU 28362. This effect of RU 28362 was blocked by coincubation with cycloheximide, indicating that the GC receptor-Ca2+ channel interaction depends on de novo protein synthesis. Dysregulated calcium homeostasis is also viewed as a candidate mechanism in brain aging. Thus, present results are consistent with the hypothesis that excessive GC-receptor activation and resultant increased Ca2+ influx may be two sequential phases of a brain-aging process that results initially in impairment of function and eventually in neuronal loss. PMID:1528857

  9. Wearable sensor glove based on conducting fabric using electrodermal activity and pulse-wave sensors for e-health application.

    PubMed

    Lee, Youngbum; Lee, Byungwoo; Lee, Myoungho

    2010-03-01

    Improvement of the quality and efficiency of health in medicine, both at home and the hospital, calls for improved sensors that might be included in a common carrier such as a wearable sensor device to measure various biosignals and provide healthcare services that use e-health technology. Designed to be user-friendly, smart clothes and gloves respond well to the end users for health monitoring. This study describes a wearable sensor glove that is equipped with an electrodermal activity (EDA) sensor, pulse-wave sensor, conducting fabric, and an embedded system. The EDA sensor utilizes the relationship between drowsiness and the EDA signal. The EDA sensors were made using a conducting fabric instead of silver chloride electrodes, as a more practical and practically wearable device. The pulse-wave sensor measurement system, which is widely applied in oriental medicinal practices, is also a strong element in e-health monitoring systems. The EDA and pulse-wave signal acquisition module was constructed by connecting the sensor to the glove via a conductive fabric. The signal acquisition module is then connected to a personal computer that displays the results of the EDA and pulse-wave signal processing analysis and gives accurate feedback to the user. This system is designed for a number of applications for the e-health services, including drowsiness detection and oriental medicine.

  10. Sub-THz thermally activated-electrical conductivity of CdS thin films

    NASA Astrophysics Data System (ADS)

    Rahman, Rezwanur; Scales, John A.

    2016-08-01

    The electrical conductivity of a CdS thin film controlled by grain structures is essential to enhance its photoconductivity to be able to be fit as a window material in CdS/CdTe heterojunction solar cells. In order to characterize a thin film, electromagnetically, we employed an open cavity resonator with a sub-millimeter Vector Network Analyzer. Our technique is capable of measuring complex dielectric permittivity, ɛ ˜ , of a photovoltaic film as thin as 0.1 μm. We measured the real part of the complex dielectric permittivity, ɛre, and electrical conductivity, σre (derived from the imaginary part, ɛim), of unannealed and annealed CdS films with thicknesses ˜0.15 μm on ˜3 mm thick-borosilicate glass substrates, at room temperature. We obtain the (thermally activated) electrical conductivity between 100 and 312 GHz, which is less in annealed samples than in unannealed ones by ˜2 orders of magnitude. Contrary to our expectations, the carrier concentrations extracted from these data by fitting a Drude model are ˜1016 cm-3 (unannealed) and ˜1014 cm-3 (annealed). We investigate the connection between the grain size and carrier concentration.

  11. Fabrication of Al-Doped ZnO Film with High Conductivity Induced by Photocatalytic Activity

    NASA Astrophysics Data System (ADS)

    Hong, Jeongsoo; Katsumata, Ken-ichi; Matsushita, Nobuhiro

    2016-06-01

    We have fabricated Al-doped ZnO films by a spin-spray method, achieving high conductivity by Al-ion doping and photocatalytic activity of the ZnO. The surface morphology of the as-deposited films was varied by changing the Al concentration and addition of citrate ions. As-deposited Al-doped ZnO film without citrate ions showed rod array structure with increasing rod width as the Al concentration was increased. Meanwhile, Al-doped ZnO film deposited with addition of citrate ions changed to exhibit dense and continuous surface morphology with high transmittance of 85%. The lowest resistivity recorded for undoped and Al-doped ZnO film was 2.1 × 10-2 Ω cm and 5.9 × 10-3 Ω cm, after ultraviolet (UV) irradiation. The reason for the decreased resistivity is thought to be that Al-ion doping and the photocatalytic activity of ZnO contributed to improve the conductivity.

  12. Charge Transport and Conductance Switching of Redox-Active Azulene Derivatives.

    PubMed

    Schwarz, Florian; Koch, Michael; Kastlunger, Georg; Berke, Heinz; Stadler, Robert; Venkatesan, Koushik; Lörtscher, Emanuel

    2016-09-19

    Azulene (Az) is a non-alternating, aromatic hydrocarbon composed of a five-membered, electron-rich and a seven-membered, electron-poor ring; an electron distribution that provides intrinsic redox activity. By varying the attachment points of the two electrode-bridging substituents to the Az center, the influence of the redox functionality on charge transport is evaluated. The conductance of the 1,3 Az derivative is at least one order of magnitude lower than those of the 2,6 Az and 4,7 Az derivatives, in agreement with density functional theory (DFT) calculations. In addition, only 1,3 Az exhibits pronounced nonlinear current-voltage characteristics with hysteresis, indicating a bias-dependent conductance switching. DFT identifies the LUMO to be nearest to the Fermi energy of the electrodes, but to be an active transport channel only in the case of the 2,6 and the 4,7 Az derivatives, whereas the 1,3 Az derivative uses the HOMO at low and the LUMO+1 at high bias. In return, the localized, weakly coupled LUMO of 1,3 Az creates a slow electron-hopping channel responsible for the voltage-induced switching due to the occupation of a single molecular orbital (MO).

  13. Fabrication of Al-Doped ZnO Film with High Conductivity Induced by Photocatalytic Activity

    NASA Astrophysics Data System (ADS)

    Hong, Jeongsoo; Katsumata, Ken-ichi; Matsushita, Nobuhiro

    2016-10-01

    We have fabricated Al-doped ZnO films by a spin-spray method, achieving high conductivity by Al-ion doping and photocatalytic activity of the ZnO. The surface morphology of the as-deposited films was varied by changing the Al concentration and addition of citrate ions. As-deposited Al-doped ZnO film without citrate ions showed rod array structure with increasing rod width as the Al concentration was increased. Meanwhile, Al-doped ZnO film deposited with addition of citrate ions changed to exhibit dense and continuous surface morphology with high transmittance of 85%. The lowest resistivity recorded for undoped and Al-doped ZnO film was 2.1 × 10-2 Ω cm and 5.9 × 10-3 Ω cm, after ultraviolet (UV) irradiation. The reason for the decreased resistivity is thought to be that Al-ion doping and the photocatalytic activity of ZnO contributed to improve the conductivity.

  14. Charge Transport and Conductance Switching of Redox-Active Azulene Derivatives.

    PubMed

    Schwarz, Florian; Koch, Michael; Kastlunger, Georg; Berke, Heinz; Stadler, Robert; Venkatesan, Koushik; Lörtscher, Emanuel

    2016-09-19

    Azulene (Az) is a non-alternating, aromatic hydrocarbon composed of a five-membered, electron-rich and a seven-membered, electron-poor ring; an electron distribution that provides intrinsic redox activity. By varying the attachment points of the two electrode-bridging substituents to the Az center, the influence of the redox functionality on charge transport is evaluated. The conductance of the 1,3 Az derivative is at least one order of magnitude lower than those of the 2,6 Az and 4,7 Az derivatives, in agreement with density functional theory (DFT) calculations. In addition, only 1,3 Az exhibits pronounced nonlinear current-voltage characteristics with hysteresis, indicating a bias-dependent conductance switching. DFT identifies the LUMO to be nearest to the Fermi energy of the electrodes, but to be an active transport channel only in the case of the 2,6 and the 4,7 Az derivatives, whereas the 1,3 Az derivative uses the HOMO at low and the LUMO+1 at high bias. In return, the localized, weakly coupled LUMO of 1,3 Az creates a slow electron-hopping channel responsible for the voltage-induced switching due to the occupation of a single molecular orbital (MO). PMID:27553767

  15. Shrinkage activates a nonselective conductance: involvement of a Walker-motif protein and PKC.

    PubMed

    Nelson, D J; Tien, X Y; Xie, W; Brasitus, T A; Kaetzel, M A; Dedman, J R

    1996-01-01

    The ability of all cells to maintain their volume during an osmotic challenge is dependent on the regulated movement of salt and water across the plasma membrane. We demonstrate the phosphorylation-dependent gating of a nonselective conductance in Caco-2 cells during cellular shrinkage. Intracellular application of exogenous purified rat brain protein kinase C (PKC) resulted in the activation of a current similar to that activated during shrinkage with a Na(+)-to-Cl- permeability ratio of approximately 1.7:1. To prevent possible PKC- and/or shrinkage-dependent activation of cystic fibrosis transmembrane regulator (CFTR), which is expressed at high levels in Caco-2 cells, a functional anti-peptide antibody, anti-CFTR505-511, was introduced into the cells via the patch pipette. Anti-CFTR505-511, which is directed against the Walker motif in the first nucleotide binding fold of CFTR, prevented the PKC/shrink-age current activation. The peptide CFTR505-511 also induced current inhibition, suggesting the possible involvement of a regulatory element in close proximity to the channel that shares sequence homology with the first nucleotide binding fold of CFTR and whose binding to the channel is required for channel gating. PMID:8772443

  16. 30 CFR 580.3 - What requirements must I follow when I conduct prospecting or research activities?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... research activities? You must conduct G&G prospecting activities or scientific research activities under this part according to: (a) The Act; (b) The regulations in this part; (c) Orders of the Director... prospecting or research activities? 580.3 Section 580.3 Mineral Resources BUREAU OF OCEAN ENERGY...

  17. 30 CFR 580.3 - What requirements must I follow when I conduct prospecting or research activities?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... research activities? You must conduct G&G prospecting activities or scientific research activities under this part according to: (a) The Act; (b) The regulations in this part; (c) Orders of the Director... prospecting or research activities? 580.3 Section 580.3 Mineral Resources BUREAU OF OCEAN ENERGY...

  18. 30 CFR 580.3 - What requirements must I follow when I conduct prospecting or research activities?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... research activities? You must conduct G&G prospecting activities or scientific research activities under this part according to: (a) The Act; (b) The regulations in this part; (c) Orders of the Director... prospecting or research activities? 580.3 Section 580.3 Mineral Resources BUREAU OF OCEAN ENERGY...

  19. In Vitro Antimicrobial Activity of a Siderophore Cephalosporin, S-649266, against Enterobacteriaceae Clinical Isolates, Including Carbapenem-Resistant Strains.

    PubMed

    Kohira, Naoki; West, Joshua; Ito, Akinobu; Ito-Horiyama, Tsukasa; Nakamura, Rio; Sato, Takafumi; Rittenhouse, Stephen; Tsuji, Masakatsu; Yamano, Yoshinori

    2015-11-16

    S-649266 is a novel siderophore cephalosporin antibiotic with a catechol moiety on the 3-position side chain. Two sets of clinical isolate collections were used to evaluate the antimicrobial activity of S-649266 against Enterobacteriaceae. These sets included 617 global isolates collected between 2009 and 2011 and 233 β-lactamase-identified isolates, including 47 KPC-, 49 NDM-, 12 VIM-, and 8 IMP-producers. The MIC90 values of S-649266 against the first set of Escherichia coli, Klebsiella pneumoniae, Serratia marcescens, Citrobacter freundii, Enterobacter aerogenes, and Enterobacter cloacae isolates were all ≤1 μg/ml, and there were only 8 isolates (1.3%) among these 617 clinical isolates with MIC values of ≥8 μg/ml. In the second set, the MIC values of S-649266 were ≤4 μg/ml against 109 strains among 116 KPC-producing and class B (metallo) carbapenemase-producing strains. In addition, S-649266 showed MIC values of ≤2 μg/ml against each of the 13 strains that produced other types of carbapenemases such as SME, NMC, and OXA-48. The mechanisms of the decreased susceptibility of 7 class B carbapenemase-producing strains with MIC values of ≥16 μg/ml are uncertain. This is the first report to demonstrate that S-649266, a novel siderophore cephalosporin, has significant antimicrobial activity against Enterobacteriaceae, including strains that produce carbapenemases such as KPC and NDM-1.

  20. Activities conducted during the definition phase of the outer planets missions program

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The activities are described of the Meteoroid Science Team for the definition phase of the outer planet missions. Studies reported include: (1) combined zodiacal experiment for the Grand Tour Missions of the outer planets, (2) optical transmission of a honeycomb panel and its effectiveness as a particle impact surface, (3) element identification data from the combined zodiacal OPGT experiment and (4) development of lightweight thermally stable mirrors.

  1. Large-conductance calcium-activated potassium current modulates excitability in isolated canine intracardiac neurons.

    PubMed

    Pérez, Guillermo J; Desai, Mayurika; Anderson, Seth; Scornik, Fabiana S

    2013-02-01

    We studied principal neurons from canine intracardiac (IC) ganglia to determine whether large-conductance calcium-activated potassium (BK) channels play a role in their excitability. We performed whole cell recordings in voltage- and current-clamp modes to measure ion currents and changes in membrane potential from isolated canine IC neurons. Whole cell currents from these neurons showed fast- and slow-activated outward components. Both current components decreased in the absence of calcium and following 1-2 mM tetraethylammonium (TEA) or paxilline. These results suggest that BK channels underlie these current components. Single-channel analysis showed that BK channels from IC neurons do not inactivate in a time-dependent manner, suggesting that the dynamic of the decay of the fast current component is akin to that of intracellular calcium. Immunohistochemical studies showed that BK channels and type 2 ryanodine receptors are coexpressed in IC principal neurons. We tested whether BK current activation in these neurons occurred via a calcium-induced calcium release mechanism. We found that the outward currents of these neurons were not affected by the calcium depletion of intracellular stores with 10 mM caffeine and 10 μM cyclopiazonic acid. Thus, in canine intracardiac neurons, BK currents are directly activated by calcium influx. Membrane potential changes elicited by long (400 ms) current injections showed a tonic firing response that was decreased by TEA or paxilline. These data strongly suggest that the BK current present in canine intracardiac neurons regulates action potential activity and could increase these neurons excitability.

  2. Up-Regulatory Effects of Curcumin on Large Conductance Ca2+-Activated K+ Channels.

    PubMed

    Chen, Qijing; Tao, Jie; Hei, Hongya; Li, Fangping; Wang, Yunman; Peng, Wen; Zhang, Xuemei

    2015-01-01

    Large conductance Ca2+-activated potassium channels (BK) are targets for research that explores therapeutic means to various diseases, owing to the roles of the channels in mediating multiple physiological processes in various cells and tissues. We investigated the pharmacological effects of curcumin, a compound isolated from the herb Curcuma longa, on BK channels. As recorded by whole-cell patch-clamp, curcumin increased BK (α) and BK (α+β1) currents in transfected HEK293 cells as well as the current density of BK in A7r5 smooth muscle cells in a dose-dependent manner. By incubating with curcumin for 24 hours, the current density of exogenous BK (α) in HEK293 cells and the endogenous BK in A7r5 cells were both enhanced notably, though the steady-state activation of the channels did not shift significantly, except for BK (α+β1). Curcumin up-regulated the BK protein expression without changing its mRNA level in A7r5 cells. The surface expression and the half-life of BK channels were also increased by curcumin in HEK293 cells. These effects of curcumin were abolished by MG-132, a proteasome inhibitor. Curcumin also increased ERK 1/2 phosphorylation, while inhibiting ERK by U0126 attenuated the curcumin-induced up-regulation of BK protein expression. We also observed that the curcumin-induced relaxation in the isolated rat aortic rings was significantly attenuated by paxilline, a BK channel specific blocker. These results show that curcumin enhances the activity of the BK channels by interacting with BK directly as well as enhancing BK protein expression through inhibiting proteasomal degradation and activating ERK signaling pathway. The findings suggest that curcumin is a potential BK channel activator and provide novel insight into its complicated pharmacological effects and the underlying mechanisms. PMID:26672753

  3. PLRP-3: Operational Perspectives of Conducting Science-Driven Extravehicular Activity with Communications Latency

    NASA Technical Reports Server (NTRS)

    Miller, Matthew J.; Lim, Darlene S. S.; Brady, Allyson; Cardman, Zena; Bell, Ernest; Garry, Brent; Reid, Donnie; Chappell, Steve; Abercromby, Andrew F. J.

    2016-01-01

    The Pavilion Lake Research Project (PLRP) is a unique platform where the combination of scientific research and human space exploration concepts can be tested in an underwater spaceflight analog environment. The 2015 PLRP field season was performed at Pavilion Lake, Canada, where science-driven exploration techniques focusing on microbialite characterization and acquisition were evaluated within the context of crew and robotic extravehicular activity (EVA) operations. The primary objectives of this analog study were to detail the capabilities, decision-making process, and operational concepts required to meet non-simulated scientific objectives during 5-minute one-way communication latency utilizing crew and robotic assets. Furthermore, this field study served as an opportunity build upon previous tests at PLRP, NASA Desert Research and Technology Studies (DRATS), and NASA Extreme Environment Mission Operations (NEEMO) to characterize the functional roles and responsibilities of the personnel involved in the distributed flight control team and identify operational constraints imposed by science-driven EVA operations. The relationship and interaction between ground and flight crew was found to be dependent on the specific scientific activities being addressed. Furthermore, the addition of a second intravehicular operator was found to be highly enabling when conducting science-driven EVAs. Future human spaceflight activities will need to cope with the added complexity of dynamic and rapid execution of scientific priorities both during and between EVA execution to ensure scientific objectives are achieved.

  4. Activity of eravacycline against Enterobacteriaceae and Acinetobacter baumannii, including multidrug-resistant isolates, from New York City.

    PubMed

    Abdallah, Marie; Olafisoye, Olawole; Cortes, Christopher; Urban, Carl; Landman, David; Quale, John

    2015-03-01

    Eravacycline demonstrated in vitro activity against a contemporary collection of more than 4,000 Gram-negative pathogens from New York City hospitals, with MIC50/MIC90 values, respectively, for Escherichia coli of 0.12/0.5 μg/ml, Klebsiella pneumoniae of 0.25/1 μg/ml, Enterobacter aerogenes of 0.25/1 μg/ml, Enterobacter cloacae 0.5/1 μg/ml, and Acinetobacter baumannii of 0.5/1 μg/ml. Activity was retained against multidrug-resistant isolates, including those expressing KPC and OXA carbapenemases. For A. baumannii, eravacycline MICs correlated with increased expression of the adeB gene. PMID:25534744

  5. Bone conducted vibration selectively activates irregular primary otolithic vestibular neurons in the guinea pig.

    PubMed

    Curthoys, Ian S; Kim, Juno; McPhedran, Samara K; Camp, Aaron J

    2006-11-01

    The main objective of this study was to determine whether bone-conducted vibration (BCV) is equally effective in activating both semicircular canal and otolith afferents in the guinea pig or whether there is preferential activation of one of these classes of vestibular afferents. To answer this question a large number (346) of single primary vestibular neurons were recorded extracellularly in anesthetized guinea pigs and were identified by their location in the vestibular nerve and classed as regular or irregular on the basis of the variability of their spontaneous discharge. If a neuron responded to angular acceleration it was classed as a semicircular canal neuron, if it responded to maintained roll or pitch tilts it was classified as an otolith neuron. Each neuron was then tested by BCV stimuli-either clicks, continuous pure tones (200-1,500 Hz) or short tone bursts (500 Hz lasting 7 ms)-delivered by a B-71 clinical bone-conduction oscillator cemented to the guinea pig's skull. All stimulus intensities were referred to that animal's own auditory brainstem response (ABR) threshold to BCV clicks, and the maximum intensity used was within the animal's physiological range and was usually around 70 dB above BCV threshold. In addition two sensitive single axis linear accelerometers cemented to the skull gave absolute values of the stimulus acceleration in the rostro-caudal direction. The criterion for a neuron being classed as activated was an audible, stimulus-locked increase in firing rate (a 10% change was easily detectable) in response to the BCV stimulus. At the stimulus levels used in this study, semicircular canal neurons, both regular and irregular, were insensitive to BCV stimuli and very few responded: only nine of 189 semicircular canal neurons tested (4.7%) showed a detectable increase in firing in response to BCV stimuli up to the maximum 2 V peak-to-peak level we delivered to the B-71 oscillator (which produced a peak-to-peak skull acceleration of around

  6. Electrical Conductivity of Rocks and Dominant Charge Carriers. Part 1; Thermally Activated Positive Holes

    NASA Technical Reports Server (NTRS)

    Freund, Friedemann T.; Freund, Minoru M.

    2012-01-01

    The prevailing view in the geophysics community is that the electrical conductivity structure of the Earth's continental crust over the 5-35 km depth range can best be understood by assuming the presence of intergranular fluids and/or of intragranular carbon films. Based on single crystal studies of melt-grown MgO, magma-derived sanidine and anorthosite feldspars and upper mantle olivine, we present evidence for the presence of electronic charge carriers, which derive from peroxy defects that are introduced during cooling, under non-equilibrium conditions, through a redox conversion of pairs of solute hydroxyl arising from dissolution of H2O.The peroxy defects become thermally activated in a 2-step process, leading to the release of defect electrons in the oxygen anion sublattice. Known as positive holes and symbolized by h(dot), these electronic charge carriers are highly mobile. Chemically equivalent to O(-) in a matrix of O(2-) they are highly oxidizing. Being metastable they can exist in the matrix of minerals, which crystallized in highly reduced environments. The h(dot) are highly mobile. They appear to control the electrical conductivity of crustal rocks in much of the 5-35 km depth range.

  7. Computational design of mixers and pumps for microfluidic systems, based on electrochemically-active conducting polymers.

    PubMed

    Kannappan, Karthik; Bogle, Gib; Travas-Sejdic, Jadranka; Williams, David E

    2011-03-28

    We present a theoretical description of the propagation of composition waves along a strip of electrochemically-active conducting polymer, upon electrochemical stimulation. We develop an efficient solution of the electro-neutral Nernst-Plank equations in 2-D for electromigration and diffusional transport in the solution based on an extension of the methods of Scharfetter and Gummel [D. L. Scharfetter and H. K. Gummel, IEEE Trans. Electron Devices, 1969, ED16, 64-77.] and of Cohen and Cooley [H. Cohen and J. W. Cooley, Biophys. J., 1965, 5, 145-162.], and demonstrate important effects of the geometry of the cell. Under some circumstances, waves reflecting back from the end of the strip are predicted. We then demonstrate theoretically how such waves, associated as they are with expansion of the polymer, could be employed to enhance mixing or induce pumping in microfluidic systems.

  8. Tremorgenic indole alkaloids potently inhibit smooth muscle high-conductance calcium-activated potassium channels.

    PubMed

    Knaus, H G; McManus, O B; Lee, S H; Schmalhofer, W A; Garcia-Calvo, M; Helms, L M; Sanchez, M; Giangiacomo, K; Reuben, J P; Smith, A B

    1994-05-17

    Tremorgenic indole alkaloids produce neurological disorders (e.g., staggers syndromes) in ruminants. The mode of action of these fungal mycotoxins is not understood but may be related to their known effects on neurotransmitter release. To determine whether these effects could be due to inhibition of K+ channels, the interaction of various indole diterpenes with high-conductance Ca(2+)-activated K+ (maxi-K) channels was examined. Paspalitrem A, paspalitrem C, aflatrem, penitrem A, and paspalinine inhibit binding of [125I]charybdotoxin (ChTX) to maxi-K channels in bovine aortic smooth muscle sarcolemmal membranes. In contrast, three structurally related compounds, paxilline, verruculogen, and paspalicine, enhanced toxin binding. As predicted from the binding studies, covalent incorporation of [125I]ChTX into the 31-kDa subunit of the maxi-K channel was blocked by compounds that inhibit [125I]ChTX binding and enhanced by compounds that stimulate [125I]ChTX binding. Modulation of [125I]ChTX binding was due to allosteric mechanisms. Despite their different effects on binding of [125I]ChTX to maxi-K channels, all compounds potently inhibited maxi-K channels in electrophysiological experiments. Other types of voltage-dependent or Ca(2+)-activated K+ channels examined were not affected. Chemical modifications of paxilline indicate a defined structure-activity relationship for channel inhibition. Paspalicine, a deshydroxy analog of paspalinine lacking tremorgenic activity, also potently blocked maxi-K channels. Taken together, these data suggest that indole diterpenes are the most potent nonpeptidyl inhibitors of maxi-K channels identified to date. Some of their pharmacological properties could be explained by inhibition of maxi-K channels, although tremorgenicity may be unrelated to channel block. PMID:7514038

  9. Feasibility of a semi-automated method for cardiac conduction velocity analysis of high-resolution activation maps.

    PubMed

    Doshi, Ashish N; Walton, Richard D; Krul, Sébastien P; de Groot, Joris R; Bernus, Olivier; Efimov, Igor R; Boukens, Bastiaan J; Coronel, Ruben

    2015-10-01

    Myocardial conduction velocity is important for the genesis of arrhythmias. In the normal heart, conduction is primarily dependent on fiber direction (anisotropy) and may be discontinuous at sites with tissue heterogeneities (trabeculated or fibrotic tissue). We present a semi-automated method for the accurate measurement of conduction velocity based on high-resolution activation mapping following central stimulation. The method was applied to activation maps created from myocardium from man, sheep and mouse with anisotropic and discontinuous conduction. Advantages of the presented method over existing methods are discussed.

  10. The NLP toxin family in Phytophthora sojae includes rapidly evolving groups that lack necrosis-inducing activity.

    PubMed

    Dong, Suomeng; Kong, Guanghui; Qutob, Dinah; Yu, Xiaoli; Tang, Junli; Kang, Jixiong; Dai, Tingting; Wang, Hai; Gijzen, Mark; Wang, Yuanchao

    2012-07-01

    Necrosis- and ethylene-inducing-like proteins (NLP) are widely distributed in eukaryotic and prokaryotic plant pathogens and are considered to be important virulence factors. We identified, in total, 70 potential Phytophthora sojae NLP genes but 37 were designated as pseudogenes. Sequence alignment of the remaining 33 NLP delineated six groups. Three of these groups include proteins with an intact heptapeptide (Gly-His-Arg-His-Asp-Trp-Glu) motif, which is important for necrosis-inducing activity, whereas the motif is not conserved in the other groups. In total, 19 representative NLP genes were assessed for necrosis-inducing activity by heterologous expression in Nicotiana benthamiana. Surprisingly, only eight genes triggered cell death. The expression of the NLP genes in P. sojae was examined, distinguishing 20 expressed and 13 nonexpressed NLP genes. Real-time reverse-transcriptase polymerase chain reaction results indicate that most NLP are highly expressed during cyst germination and infection stages. Amino acid substitution ratios (Ka/Ks) of 33 NLP sequences from four different P. sojae strains resulted in identification of positive selection sites in a distinct NLP group. Overall, our study indicates that expansion and pseudogenization of the P. sojae NLP family results from an ongoing birth-and-death process, and that varying patterns of expression, necrosis-inducing activity, and positive selection suggest that NLP have diversified in function.

  11. An improved chloride-conducting channelrhodopsin for light-induced inhibition of neuronal activity in vivo

    PubMed Central

    Wietek, Jonas; Beltramo, Riccardo; Scanziani, Massimo; Hegemann, Peter; Oertner, Thomas G.; Simon Wiegert, J.

    2015-01-01

    Channelrhodopsins are light-gated cation channels that have been widely used for optogenetic stimulation of electrically excitable cells. Replacement of a glutamic acid in the central gate with a positively charged amino acid residue reverses the ion selectivity and produces chloride-conducting ChRs (ChloCs). Expressed in neurons, published ChloCs produced a strong shunting effect but also a small, yet significant depolarization from the resting potential. Depending on the state of the neuron, the net result of illumination might therefore be inhibitory or excitatory with respect to action potential generation. Here we report two additional amino acid substitutions that significantly shift the reversal potential of improved ChloC (iChloC) to the reversal potential of endogenous GABAA receptors. As a result, light-evoked membrane depolarization was strongly reduced and spike initiation after current injection or synaptic stimulation was reliably inhibited in iChloC-transfected neurons in vitro. In the primary visual cortex of anesthetized mice, activation of iChloC suppressed spiking activity evoked by visual stimulation. Due to its high operational light sensitivity, iChloC makes it possible to inhibit neurons in a large volume of brain tissue from a small, point-like light source. PMID:26443033

  12. A Comparison of the Activation Enthalpies for Ionic Conduction in Animal and Plant Tissue

    NASA Astrophysics Data System (ADS)

    Hart, Francis X.

    1997-11-01

    The electrical properties of biological materials are determined by the transport of ions. There are two stages in the transport of an ion along a surface, such as a cell membrane: ``detrapping'' of the ion from a binding site and (2) ``hopping'' of the freed ion from site to site. An activation enthalpy can be determined for each stage by measuring the impedance spectrum of the tissue over a range of temperatures. A Hewlett Packard 4192A Low Frequency Impedance Analyzer was used to measure the impedance spectra of apples and of crayfish tail muscle over a range of temperatures from about 15^oC to 35^oC. At each temperature a complex-valued, non-linear, least-squares fit of the impedance data was made to a three-component circuit model. From the fitted model values the low frequency tissue conductivity and the high frequency power-law exponent and prefactor were obtained. Arrhenius plots yielded separate activation enthalpies for the detrapping (Hf) and hopping (Hm). For both apples and crayfish Hf is on the order of kT (0.025 eV) whereas Hm is on the order of 0.15 eV.

  13. Calcium activates the light-dependent conductance in melanopsin-expressing photoreceptors of amphioxus.

    PubMed

    Peinado, Gabriel; Osorno, Tomás; Gomez, María del Pilar; Nasi, Enrico

    2015-06-23

    Melanopsin, the photopigment of the "circadian" receptors that regulate the biological clock and the pupillary reflex in mammals, is homologous to invertebrate rhodopsins. Evidence supporting the involvement of phosphoinositides in light-signaling has been garnered, but the downstream effectors that control the light-dependent conductance remain unknown. Microvillar photoreceptors of the primitive chordate amphioxus also express melanopsin and transduce light via phospholipase-C, apparently not acting through diacylglycerol. We therefore examined the role of calcium in activating the photoconductance, using simultaneous, high time-resolution measurements of membrane current and Ca(2+) fluorescence. The light-induced calcium rise precedes the onset of the photocurrent, making it a candidate in the activation chain. Moreover, photolysis of caged Ca elicits an inward current of similar size, time course and pharmacology as the physiological photoresponse, but with a much shorter latency. Internally released calcium thus emerges as a key messenger to trigger the opening of light-dependent channels in melanopsin-expressing microvillar photoreceptors of early chordates.

  14. Calcium activates the light-dependent conductance in melanopsin-expressing photoreceptors of amphioxus

    PubMed Central

    Peinado, Gabriel; Osorno, Tomás; Gomez, María del Pilar; Nasi, Enrico

    2015-01-01

    Melanopsin, the photopigment of the “circadian” receptors that regulate the biological clock and the pupillary reflex in mammals, is homologous to invertebrate rhodopsins. Evidence supporting the involvement of phosphoinositides in light-signaling has been garnered, but the downstream effectors that control the light-dependent conductance remain unknown. Microvillar photoreceptors of the primitive chordate amphioxus also express melanopsin and transduce light via phospholipase-C, apparently not acting through diacylglycerol. We therefore examined the role of calcium in activating the photoconductance, using simultaneous, high time-resolution measurements of membrane current and Ca2+ fluorescence. The light-induced calcium rise precedes the onset of the photocurrent, making it a candidate in the activation chain. Moreover, photolysis of caged Ca elicits an inward current of similar size, time course and pharmacology as the physiological photoresponse, but with a much shorter latency. Internally released calcium thus emerges as a key messenger to trigger the opening of light-dependent channels in melanopsin-expressing microvillar photoreceptors of early chordates. PMID:26056310

  15. Low skin conductance activity in infancy predicts aggression in toddlers 2 years later.

    PubMed

    Baker, Erika; Shelton, Katherine H; Baibazarova, Eugenia; Hay, Dale F; van Goozen, Stephanie H M

    2013-06-01

    Low autonomic nervous system activity is claimed to be a biomarker for aggressive and antisocial behavior. Although there is evidence that low skin conductance activity (SCA) accounts for variation in the severity of antisocial behavior and predicts the onset of aggression in children and adults, it is unknown whether SCA measured in infancy can predict the development of aggression. We measured SCA in 70 typically developing 1-year-old infants at baseline, during an orienting habituation paradigm, and during a fear challenge. We also observed the infants' fear behavior, and each mother rated her infant's temperament and her attachment to her child. At follow-up, mothers rated the children at 3 years old for aggressive and nonaggressive behavior problems. Low infant SCA predicted aggressive behavior, but there was no association between SCA and nonaggressive behavior problems. Mothers' ratings of the infants' temperament and their maternal attachment and the infants' observed fearlessness did not predict later aggression. These results suggest that SCA is a specific biomarker for aggression in low-risk samples of infants.

  16. Calcium activates the light-dependent conductance in melanopsin-expressing photoreceptors of amphioxus.

    PubMed

    Peinado, Gabriel; Osorno, Tomás; Gomez, María del Pilar; Nasi, Enrico

    2015-06-23

    Melanopsin, the photopigment of the "circadian" receptors that regulate the biological clock and the pupillary reflex in mammals, is homologous to invertebrate rhodopsins. Evidence supporting the involvement of phosphoinositides in light-signaling has been garnered, but the downstream effectors that control the light-dependent conductance remain unknown. Microvillar photoreceptors of the primitive chordate amphioxus also express melanopsin and transduce light via phospholipase-C, apparently not acting through diacylglycerol. We therefore examined the role of calcium in activating the photoconductance, using simultaneous, high time-resolution measurements of membrane current and Ca(2+) fluorescence. The light-induced calcium rise precedes the onset of the photocurrent, making it a candidate in the activation chain. Moreover, photolysis of caged Ca elicits an inward current of similar size, time course and pharmacology as the physiological photoresponse, but with a much shorter latency. Internally released calcium thus emerges as a key messenger to trigger the opening of light-dependent channels in melanopsin-expressing microvillar photoreceptors of early chordates. PMID:26056310

  17. Applying the Model of Goal-Directed Behavior, Including Descriptive Norms, to Physical Activity Intentions: A Contribution to Improving the Theory of Planned Behavior.

    PubMed

    Esposito, Gabriele; van Bavel, René; Baranowski, Tom; Duch-Brown, Néstor

    2016-08-01

    The theory of planned behavior (TPB) has received its fair share of criticism lately, including calls for it to retire. We contribute to improving the theory by testing extensions such as the model of goal-directed behavior (MGDB, which adds desire and anticipated positive and negative emotions) applied to physical activity (PA) intention. We also test the inclusion of a descriptive norms construct as an addition to the subjective norms construct, also applied to PA, resulting in two additional models: TPB including descriptive norms (TPB + DN) and MGDB including descriptive norms (MGDB + DN). The study is based on an online survey of 400 young adult Internet users, previously enrolled in a subject pool. Confirmatory factor analysis (CFA) showed that TPB and TPB + DN were not fit for purpose, while MGDB and MGDB + DN were. Structural equation modelling (SEM) conducted on MGDB and MGDB + DN showed that the inclusion of descriptive norms took over the significance of injunctive norms, and increased the model's account of total variance in intention to be physically active. PMID:27229344

  18. 40 CFR 745.230 - Work practice standards for conducting lead-based paint activities: public and commercial...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CONTROL ACT LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Lead-Based Paint Activities § 745.230 Work practice standards for conducting lead-based paint activities: public and... lead-based paint activities: public and commercial buildings, bridges and superstructures....

  19. 40 CFR 745.230 - Work practice standards for conducting lead-based paint activities: public and commercial...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CONTROL ACT LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Lead-Based Paint Activities § 745.230 Work practice standards for conducting lead-based paint activities: public and... lead-based paint activities: public and commercial buildings, bridges and superstructures....

  20. 40 CFR 745.230 - Work practice standards for conducting lead-based paint activities: public and commercial...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CONTROL ACT LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Lead-Based Paint Activities § 745.230 Work practice standards for conducting lead-based paint activities: public and... lead-based paint activities: public and commercial buildings, bridges and superstructures....

  1. 40 CFR 745.230 - Work practice standards for conducting lead-based paint activities: public and commercial...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CONTROL ACT LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Lead-Based Paint Activities § 745.230 Work practice standards for conducting lead-based paint activities: public and... lead-based paint activities: public and commercial buildings, bridges and superstructures....

  2. 40 CFR 745.230 - Work practice standards for conducting lead-based paint activities: public and commercial...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CONTROL ACT LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Lead-Based Paint Activities § 745.230 Work practice standards for conducting lead-based paint activities: public and... lead-based paint activities: public and commercial buildings, bridges and superstructures....

  3. 77 FR 38082 - Certain Activated Carbon from China; Notice of Commission Determination To Conduct a Full Five...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-26

    ... COMMISSION Certain Activated Carbon from China; Notice of Commission Determination To Conduct a Full Five... Activated Carbon From China AGENCY: United States International Trade Commission. ACTION: Notice. SUMMARY... whether revocation of the antidumping duty order on certain activated carbon from China would be likely...

  4. Cystic fibrosis transmembrane conductance regulator activation stimulates endosome fusion in vivo.

    PubMed Central

    Biwersi, J; Emans, N; Verkman, A S

    1996-01-01

    Previous studies have suggested a role for cystic fibrosis transmembrane conductance regulator (CFTR) in the regulation of intracellular vesicular trafficking. A quantitative fluorescence method was used to test the hypothesis that CFTR expression and activation affects endosome-endosome fusion in intact cells. Endosomes from CFTR-expressing and control (vector-transfected) Swiss 3T3 fibroblasts were labeled by internalization with 4,4-difluoro-5,7-dimethyl-4-bora-3a, 4a-diaza-s-indacene (Bodipy)-avidin, a fluid-phase marker whose fluorescence increases approximately 8-fold upon biotin binding. Cells were washed, chased, and then labeled with biotin-albumin or biotin-transferrin. The fraction of Bodipy-avidin-labeled endosomes that fused with biotin-containing endosomes (f(fusion)) was quantified by ratio imaging microfluorimetry. Endosome fusion in unstimulated CFTR-expressing cells was similar to that in control cells. However, in CFTR-expressing cells activated by forskolin, ffusion was increased by 1.30 +/- 0.18- and 2.65 +/- 0.17-fold for a 0 and 10 min chase time between avidin and biotin-albumin pulses; f(fusion) also increased (1.32 +/- 0.11-fold) when biotin-transferrin replaced biotin-albumin. The stimulation of endosome fusion was not due to differences in rates of endocytosis or endosomal acidification. Endosome fusion was not stimulated by forskolin in Cl--depleted CFTR-expressing cells, suggesting that the increase in endosome fusion is due to the CFTR chloride channel activity. These results provide evidence that CFTR is involved in the regulation of endosome fusion and, thus, a possible basis for the cellular defects associated with cystic fibrosis. Images Fig. 1 Fig. 3 PMID:8901608

  5. Intermediate Conductance Ca2+-Activated K+ Channels Modulate Human Placental Trophoblast Syncytialization

    PubMed Central

    Díaz, Paula; Wood, Amber M.; Sibley, Colin P.; Greenwood, Susan L.

    2014-01-01

    Regulation of human placental syncytiotrophoblast renewal by cytotrophoblast migration, aggregation/fusion and differentiation is essential for successful pregnancy. In several tissues, these events are regulated by intermediate conductance Ca2+-activated K+ channels (IKCa), in part through their ability to regulate cell volume. We used cytotrophoblasts in primary culture to test the hypotheses that IKCa participate in the formation of multinucleated syncytiotrophoblast and in syncytiotrophoblast volume homeostasis. Cytotrophoblasts were isolated from normal term placentas and cultured for 66 h. This preparation recreates syncytiotrophoblast formation in vivo, as mononucleate cells (15 h) fuse into multinucleate syncytia (66 h) concomitant with elevated secretion of human chorionic gonadotropin (hCG). Cells were treated with the IKCa inhibitor TRAM-34 (10 µM) or activator DCEBIO (100 µM). Culture medium was collected to measure hCG secretion and cells fixed for immunofluorescence with anti-IKCa and anti-desmoplakin antibodies to assess IKCa expression and multinucleation respectively. K+ channel activity was assessed by measuring 86Rb efflux at 66 h. IKCa immunostaining was evident in nucleus, cytoplasm and surface of mono- and multinucleate cells. DCEBIO increased 86Rb efflux 8.3-fold above control and this was inhibited by TRAM-34 (85%; p<0.0001). Cytotrophoblast multinucleation increased 12-fold (p<0.05) and hCG secretion 20-fold (p<0.05), between 15 and 66 h. Compared to controls, DCEBIO reduced multinucleation by 42% (p<0.05) and hCG secretion by 80% (p<0.05). TRAM-34 alone did not affect cytotrophoblast multinucleation or hCG secretion. Hyposmotic solution increased 86Rb efflux 3.8-fold (p<0.0001). This effect was dependent on extracellular Ca2+, inhibited by TRAM-34 and 100 nM charybdotoxin (85% (p<0.0001) and 43% respectively) but unaffected by 100 nM apamin. In conclusion, IKCa are expressed in cytotrophoblasts and their activation inhibits the formation

  6. 30 CFR 250.281 - What must I do to conduct activities under the approved EP, DPP, or DOCD?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... procedures in 15 CFR part 930 subpart H. The Secretary of Commerce will either: (A) Grant your appeal by...) Approval restrictions for permits for activities conducted under EPs. The District Manager or...

  7. 30 CFR 250.281 - What must I do to conduct activities under the approved EP, DPP, or DOCD?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...; or (ii) Appeal the State's objection to the Secretary of Commerce using the procedures in 15 CFR part... permits for activities conducted under EPs. The District Manager or Regional Supervisor will not...

  8. Validation of a high throughput flow cytometric in vitro micronucleus assay including assessment of metabolic activation in TK6 cells.

    PubMed

    Thougaard, Annemette V; Christiansen, Joan; Mow, Tomas; Hornberg, Jorrit J

    2014-12-01

    Genotoxicity is an unacceptable property for new drug candidates and we employ three screening assays during the drug discovery process to identify genotoxicity early and optimize chemical series. One of these methods is the flow cytometric in vitro micronucleus assay for which protocol optimizations have been described recently. Here, we report further validation of the assay in TK6 cells including assessment of metabolic activation. We first optimized assay conditions to allow for testing with and without metabolic activation in parallel in a 96-well plate format. Then, we tested a set of 48 compounds carefully selected to contain known in vivo genotoxins, nongenotoxins and drugs. Avoidance of irrelevant positives, a known issue with mammalian cell-based genotoxicity assays, is important to prevent early deselection of potentially promising compounds. Therefore, we enriched the validation set with compounds that were previously reported to produce irrelevant positive results in mammalian cell-based genotoxicity assays. The resulting dataset was used to set the relevant cut-off values for scoring a compound positive or negative, such that we obtained an optimal balance of high sensitivity (88%) and high specificity (87%). Finally, we tested an additional set of 16 drugs to further probe assay performance and 14 of them were classified correctly. To our knowledge, the present study is the most comprehensive validation of the in vitro flow cytometric micronucleus assay and the first to report parallel assessment with metabolic activation in reasonable throughput. The assay allows for rapidly screening novel compounds for genotoxicity and is therefore well-suited for use in early drug discovery projects. Environ.

  9. In Situ Measurement of Voltage-Induced Stress in Conducting Polymers with Redox-Active Dopants.

    PubMed

    Sen, Sujat; Kim, Sung Yeol; Palmore, Lia R; Jin, Shenghua; Jadhav, Nitin; Chason, Eric; Palmore, G Tayhas R

    2016-09-14

    Minimization of stress-induced mechanical rupture and delamination of conducting polymer (CP) films is desirable to prevent failure of devices based on these materials. Thus, precise in situ measurement of voltage-induced stress within these films should provide insight into the cause of these failure mechanisms. The evolution of stress in films of polypyrrole (pPy), doped with indigo carmine (IC), was measured in different electrochemical environments using the multibeam optical stress sensor (MOSS) technique. The stress in these films gradually increases to a constant value during voltage cycling, revealing an initial break-in period for CP films. The nature of the ions involved in charge compensation of pPy[IC] during voltage cycling was determined from electrochemical quartz crystal microbalance (EQCM) data. The magnitude of the voltage-induced stress within pPy[IC] at neutral pH correlated with the radius of the hydrated mobile ion in the order Li(+) > Na(+) > K(+). At acidic pH, the IC dopant in pPy[IC] undergoes reversible oxidation and reduction within the range of potentials investigated, providing a secondary contribution to the observed voltage-induced stress. We report on the novel stress response of these polymers due to the presence of pH-dependent redox-active dopants and how it can affect material performance.

  10. Down-regulation of the small conductance calcium-activated potassium channels in diabetic mouse atria.

    PubMed

    Yi, Fu; Ling, Tian-You; Lu, Tong; Wang, Xiao-Li; Li, Jingchao; Claycomb, William C; Shen, Win-Kuang; Lee, Hon-Chi

    2015-03-13

    The small conductance Ca(2+)-activated K(+) (SK) channels have recently been found to be expressed in the heart, and genome-wide association studies have shown that they are implicated in atrial fibrillation. Diabetes mellitus is an independent risk factor of atrial fibrillation, but the ionic mechanism underlying this relationship remains unclear. We hypothesized that SK channel function is abnormal in diabetes mellitus, leading to altered cardiac electrophysiology. We found that in streptozotocin-induced diabetic mice, the expression of SK2 and SK3 isoforms was down-regulated by 85 and 92%, respectively, whereas that of SK1 was not changed. SK currents from isolated diabetic mouse atrial myocytes were significantly reduced compared with controls. The resting potentials of isolated atrial preparations were similar between control and diabetic mice, but action potential durations were significantly prolonged in the diabetic atria. Exposure to apamin significantly prolonged action potential durations in control but not in diabetic atria. Production of reactive oxygen species was significantly increased in diabetic atria and in high glucose-cultured HL-1 cells, whereas exposure of HL-1 cells in normal glucose culture to H2O2 reduced the expression of SK2 and SK3. Tyrosine nitration in SK2 and SK3 was significantly increased by high glucose culture, leading to accelerated channel turnover. Treatment with Tiron prevented these changes. Our results suggest that increased oxidative stress in diabetes results in SK channel-associated electrical remodeling in diabetic atria and may promote arrhythmogenesis. PMID:25605734

  11. Four-point probe electrical resistivity scanning system for large area conductivity and activation energy mapping.

    PubMed

    Shimanovich, Klimentiy; Bouhadana, Yaniv; Keller, David A; Rühle, Sven; Anderson, Assaf Y; Zaban, Arie

    2014-05-01

    The electrical properties of metal oxides play a crucial role in the development of new photovoltaic (PV) systems. Here we demonstrate a general approach for the determination and analysis of these properties in thin films of new metal oxide based PV materials. A high throughput electrical scanning system, which facilitates temperature dependent measurements at different atmospheres for highly resistive samples, was designed and constructed. The instrument is capable of determining conductivity and activation energy values for relatively large sample areas, of about 72 × 72 mm(2), with the implementation of geometrical correction factors. The efficiency of our scanning system was tested using two different samples of CuO and commercially available Fluorine doped tin oxide coated glass substrates. Our high throughput tool was able to identify the electrical properties of both resistive metal oxide thin film samples with high precision and accuracy. The scanning system enabled us to gain insight into transport mechanisms with novel compositions and to use those insights to make smart choices when choosing materials for our multilayer thin film all oxide photovoltaic cells. PMID:24880411

  12. Fear conditioning suppresses large-conductance calcium-activated potassium channels in lateral amygdala neurons.

    PubMed

    Sun, P; Zhang, Q; Zhang, Y; Wang, F; Wang, L; Yamamoto, R; Sugai, T; Kato, N

    2015-01-01

    It was previously shown that depression-like behavior is accompanied with suppression of the large-conductance calcium activated potassium (BK) channel in cingulate cortex pyramidal cells. To test whether BK channels are also involved in fear conditioning, we studied neuronal properties of amygdala principal cells in fear conditioned mice. After behavior, we made brain slices containing the amygdala, the structure critically relevant to fear memory. The resting membrane potential in lateral amygdala (LA) neurons obtained from fear conditioned mice (FC group) was more depolarized than in neurons from naïve controls. The frequencies of spikes evoked by current injections were higher in neurons from FC mice, demonstrating that excitability of LA neurons was elevated by fear conditioning. The depolarization in neurons from FC mice was shown to depend on BK channels by using the BK channel blocker charybdotoxin. Suppression of BK channels in LA neurons from the FC group was further confirmed on the basis of the spike width, since BK channels affect the descending phase of spikes. Spikes were broader in the FC group than those in the naïve control in a manner dependent on BK channels. Consistently, quantitative real-time PCR revealed a decreased expression of BK channel mRNA. The present findings suggest that emotional disorder manifested in the forms of fear conditioning is accompanied with BK channel suppression in the amygdala, the brain structure critical to this emotional disorder.

  13. Small-conductance Ca2+ -activated K+ channels and cardiac arrhythmias.

    PubMed

    Zhang, Xiao-Dong; Lieu, Deborah K; Chiamvimonvat, Nipavan

    2015-08-01

    Small-conductance Ca2+ -activated K+ (SK, KCa2) channels are unique in that they are gated solely by changes in intracellular Ca2+ and, hence, function to integrate intracellular Ca2+ and membrane potentials on a beat-to-beat basis. Recent studies have provided evidence for the existence and functional significance of SK channels in the heart. Indeed, our knowledge of cardiac SK channels has been greatly expanded over the past decade. Interests in cardiac SK channels are further driven by recent studies suggesting the critical roles of SK channels in human atrial fibrillation, the SK channel as a possible novel therapeutic target in atrial arrhythmias, and upregulation of SK channels in heart failure in animal models and in human heart failure. However, there remain critical gaps in our knowledge. Specifically, blockade of SK channels in cardiac arrhythmias has been shown to be both antiarrhythmic and proarrhythmic. This contemporary review provides an overview of the literature on the role of cardiac SK channels in cardiac arrhythmias and serves as a discussion platform for the current clinical perspectives. At the translational level, development of SK channel blockers as a new therapeutic strategy in the treatment of atrial fibrillation and the possible proarrhythmic effects merit further considerations and investigations.

  14. In Situ Measurement of Voltage-Induced Stress in Conducting Polymers with Redox-Active Dopants.

    PubMed

    Sen, Sujat; Kim, Sung Yeol; Palmore, Lia R; Jin, Shenghua; Jadhav, Nitin; Chason, Eric; Palmore, G Tayhas R

    2016-09-14

    Minimization of stress-induced mechanical rupture and delamination of conducting polymer (CP) films is desirable to prevent failure of devices based on these materials. Thus, precise in situ measurement of voltage-induced stress within these films should provide insight into the cause of these failure mechanisms. The evolution of stress in films of polypyrrole (pPy), doped with indigo carmine (IC), was measured in different electrochemical environments using the multibeam optical stress sensor (MOSS) technique. The stress in these films gradually increases to a constant value during voltage cycling, revealing an initial break-in period for CP films. The nature of the ions involved in charge compensation of pPy[IC] during voltage cycling was determined from electrochemical quartz crystal microbalance (EQCM) data. The magnitude of the voltage-induced stress within pPy[IC] at neutral pH correlated with the radius of the hydrated mobile ion in the order Li(+) > Na(+) > K(+). At acidic pH, the IC dopant in pPy[IC] undergoes reversible oxidation and reduction within the range of potentials investigated, providing a secondary contribution to the observed voltage-induced stress. We report on the novel stress response of these polymers due to the presence of pH-dependent redox-active dopants and how it can affect material performance. PMID:27579593

  15. Superoxide activates a GDP-sensitive proton conductance in skeletal muscle mitochondria from king penguin (Aptenodytes patagonicus).

    PubMed

    Talbot, Darren A; Hanuise, Nicolas; Rey, Benjamin; Rouanet, Jean-Louis; Duchamp, Claude; Brand, Martin D

    2003-12-26

    We present the partial nucleotide sequence of the avian uncoupling protein (avUCP) gene from king penguin (Aptenodytes patagonicus), showing that the protein is 88-92% identical to chicken (Gallus gallus), turkey (Meleagris gallopavo), and hummingbird (Eupetomena macroura). We show that superoxide activates the proton conductance of mitochondria isolated from king penguin skeletal muscle. GDP abolishes the superoxide-activated proton conductance, indicating that it is mediated via avUCP. In the absence of superoxide there is no GDP-sensitive component of the proton conductance from penguin muscle mitochondria demonstrating that avUCP plays no role in the basal proton leak. PMID:14651968

  16. Intracellular pH regulates basolateral K+ and Cl- conductances in colonic epithelial cells by modulating Ca2+ activation

    PubMed Central

    1991-01-01

    The role of intracellular pH as a modulator of basolateral K+ and Cl- conductances in epithelial cells was studied using digitonin- permeabilized colonic cell layers so that cytosolic pH could be clamped at specific values, while basolateral K+ and Cl- conductances were activated by stepwise increases in intracellular free Ca2+. Increasing the intracellular pH from 6.6 to 8.0 enhanced the sensitivity of both ionic conductances to intracellular Ca2+, but changing extracellular pH had no effect. Maximal K+ and Cl- currents activated by Ca2+ were not affected by changes in intracellular pH, suggesting that protons do not alter the conduction properties of the channels. Hill analysis of the Ca2+ activation process revealed that raising the cytosolic pH from 6.6 to 8.0 reduced the K1/2 for Ca2+ activation. In the absence of Ca2+, changes in intracellular pH did not have a significant effect on the basolateral K+ and Cl- conductances. These results are consistent with the notion that changes in cytosolic pH can modulate basolateral conductances by modifying the action of calcium, perhaps by acting at or near the activation site to provide a mechanism of variable "gain control." PMID:1719125

  17. 14 CFR 440.11 - Duration of coverage for licensed launch, including suborbital launch, or permitted activities...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... necessary. That determination is made through the risk analysis conducted before the launch to determine MPL... recovery; or (ii) The FAA's determination that risk to third parties and Government property as a result...

  18. 20 CFR 670.430 - What entities conduct outreach and admissions activities for the Job Corps program?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... activities for the Job Corps program? 670.430 Section 670.430 Employees' Benefits EMPLOYMENT AND TRAINING... contact with youth over substantial periods of time and are able to offer reliable information about the needs of youth, conduct outreach and admissions activities. The Regional Director awards contracts...

  19. 30 CFR 285.652 - How long do I have to conduct activities under an approved GAP?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... an approved GAP? 285.652 Section 285.652 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF... SHELF Plans and Information Requirements Activities Under An Approved Gap § 285.652 How long do I have to conduct activities under an approved GAP? After MMS approves your GAP, you have: (a) For a...

  20. Bone conducted vibration activates the vestibulo-ocular reflex in the guinea pig.

    PubMed

    Vulovic, Vedran; Curthoys, Ian S

    2011-08-10

    The aim of the study was: (a) to test whether short duration (6 ms) 500 Hz bone-conducted vibration (BCV) of the skull in alert head free guinea pigs would elicit eye movements; (b) to test whether these eye movements were vestibular in origin; and (c) to determine whether they corresponded to human eye movements to such stimuli. In this way we sought to establish the guinea pig as an acceptable model for testing the mechanism of the effect BCV on the vestibulo-ocular reflex. Consistent short-latency stimulus-locked responses to BCV were observed. The magnitude of eye displacement was directly related to stimulus intensity as recorded by accelerometers cemented onto the animal's skull. The strongest and most consistent response component was intorsion of both eyes. In lateral-eyed animals intorsion is produced by the combined contraction of the inferior rectus and superior oblique muscles. In humans the same pair of muscles acts to cause depression of the eye. To test whether the movements were vestibular we selectively ablated the vestibular endorgans: 3 of the 8 animals underwent a bilateral intratympanic injection of gentamicin, an ototoxic aminoglycoside antibiotic, to ablate their vestibular receptors. After ablation there was an overall reduction in the magnitude of eye displacement, as well as a reduction in the effectiveness of the BCV stimulus to elicit eye movements. The animals' hearing, as measured by the threshold for auditory brainstem responses, remained unchanged after gentamicin, confirming that the cochlea was not affected. The reduced magnitude of responses after vestibular receptor ablation demonstrates that the eye-movement responses to BCV are probably caused by the stimulation of vestibular receptors, which in turn activate the vestibulo-ocular reflex.

  1. Multi-ion occupancy alters gating in high-conductance, Ca(2+)-activated K+ channels

    PubMed Central

    1991-01-01

    In this study, single-channel recordings of high-conductance Ca(2+)- activated K+ channels from rat skeletal muscle inserted into planar lipid bilayer were used to analyze the effects of two ionic blockers, Ba2+ and Na+, on the channel's gating reactions. The gating equilibrium of the Ba(2+)-blocked channel was investigated through the kinetics of the discrete blockade induced by Ba2+ ions. Gating properties of Na(+)- blocked channels could be directly characterized due to the very high rates of Na+ blocking/unblocking reactions. While in the presence of K+ (5 mM) in the external solution Ba2+ is known to stabilize the open state of the blocked channel (Miller, C., R. Latorre, and I. Reisin. 1987. J. Gen. Physiol. 90:427-449), we show that the divalent blocker stabilizes the closed-blocked state if permeant ions are removed from the external solution (K+ less than 10 microM). Ionic substitutions in the outer solution induce changes in the gating equilibrium of the Ba(2+)-blocked channel that are tightly correlated to the inhibition of Ba2+ dissociation by external monovalent cations. In permeant ion-free external solutions, blockade of the channel by internal Na+ induces a shift (around 15 mV) in the open probability--voltage curve toward more depolarized potentials, indicating that Na+ induces a stabilization of the closed-blocked state, as does Ba2+ under the same conditions. A kinetic analysis of the Na(+)-blocked channel indicates that the closed- blocked state is favored mainly by a decrease in opening rate. Addition of 1 mM external K+ completely inhibits the shift in the activation curve without affecting the Na(+)-induced reduction in the apparent single-channel amplitude. The results suggest that in the absence of external permeant ions internal blockers regulate the permeant ion occupancy of a site near the outer end of the channel. Occupancy of this site appears to modulate gating primarily by speeding the rate of channel opening. PMID:2056305

  2. Monoaminergic tone supports conductance correlations and stabilizes activity features in pattern generating neurons of the lobster, Panulirus interruptus.

    PubMed

    Krenz, Wulf-Dieter; Parker, Anna R; Rodgers, Edmund; Baro, Deborah J

    2015-01-01

    Experimental and computational studies demonstrate that different sets of intrinsic and synaptic conductances can give rise to equivalent activity patterns. This is because the balance of conductances, not their absolute values, defines a given activity feature. Activity-dependent feedback mechanisms maintain neuronal conductance correlations and their corresponding activity features. This study demonstrates that tonic nM concentrations of monoamines enable slow, activity-dependent processes that can maintain a correlation between the transient potassium current (I(A) and the hyperpolarization activated current (Ih) over the long-term (i.e., regulatory change persists for hours after removal of modulator). Tonic 5 nM DA acted through an RNA interference silencing complex (RISC)- and RNA polymerase II-dependent mechanism to maintain a long-term positive correlation between I(A) and Ih in the lateral pyloric neuron (LP) but not in the pyloric dilator neuron (PD). In contrast, tonic 5 nM 5HT maintained a RISC-dependent positive correlation between I(A) and Ih in PD but not LP over the long-term. Tonic 5 nM OCT maintained a long-term negative correlation between I(A) and Ih in PD but not LP; however, it was only revealed when RISC was inhibited. This study also demonstrated that monoaminergic tone can also preserve activity features over the long-term: the timing of LP activity, LP duty cycle and LP spike number per burst were maintained by tonic 5 nM DA. The data suggest that low-level monoaminergic tone acts through multiple slow processes to permit cell-specific, activity-dependent regulation of ionic conductances to maintain conductance correlations and their corresponding activity features over the long-term. PMID:26539083

  3. Monoaminergic tone supports conductance correlations and stabilizes activity features in pattern generating neurons of the lobster, Panulirus interruptus

    PubMed Central

    Krenz, Wulf-Dieter; Parker, Anna R.; Rodgers, Edmund; Baro, Deborah J.

    2015-01-01

    Experimental and computational studies demonstrate that different sets of intrinsic and synaptic conductances can give rise to equivalent activity patterns. This is because the balance of conductances, not their absolute values, defines a given activity feature. Activity-dependent feedback mechanisms maintain neuronal conductance correlations and their corresponding activity features. This study demonstrates that tonic nM concentrations of monoamines enable slow, activity-dependent processes that can maintain a correlation between the transient potassium current (IA) and the hyperpolarization activated current (Ih) over the long-term (i.e., regulatory change persists for hours after removal of modulator). Tonic 5 nM DA acted through an RNA interference silencing complex (RISC)- and RNA polymerase II-dependent mechanism to maintain a long-term positive correlation between IA and Ih in the lateral pyloric neuron (LP) but not in the pyloric dilator neuron (PD). In contrast, tonic 5 nM 5HT maintained a RISC-dependent positive correlation between IA and Ih in PD but not LP over the long-term. Tonic 5 nM OCT maintained a long-term negative correlation between IA and Ih in PD but not LP; however, it was only revealed when RISC was inhibited. This study also demonstrated that monoaminergic tone can also preserve activity features over the long-term: the timing of LP activity, LP duty cycle and LP spike number per burst were maintained by tonic 5 nM DA. The data suggest that low-level monoaminergic tone acts through multiple slow processes to permit cell-specific, activity-dependent regulation of ionic conductances to maintain conductance correlations and their corresponding activity features over the long-term. PMID:26539083

  4. [Evaluation of an obesity prevention intervention which included nutrition education and physical activity applied in public schools of Santiago, Chile].

    PubMed

    Kain, Juliana; Leyton, Bárbara; Concha, Fernando; Weisstaub, Gerardo; Lobos, Luz; Bustos, Nelly; Vio, Fernando

    2012-03-01

    The main objective of this study was to assess the effectiveness of an obesity prevention intervention which included nutrition education and physical activity applied to low income Chilean children in a longitudinal three-year follow-up study. Participants included all 4-7 year old children from 7 public schools located in a low socioeconomic district of Santiago. The main aspects of the intervention were: training of teachers so they could apply an educational program on healthy eating, increase in physical education classes from 3 to 4 per week, and improvement of their quality. Weight, height, waist circumference (WC) and the 6-minute walk distance (6MWD) were assessed yearly in 597 children. We calculated BMI, BMI Z, % normal (N), overweight (OW) and obesity (OB), WC > 90th percentile (NHANES III) and fitness (6MWD/height). Annual changes in BMI Z, WC, 6MWD and fitness were assessed, using repeated measures ANOVA and the test of proportions. Knowledge in healthy eating was assessed during 2 of the 3 years. Results showed that % OB remained unchanged for 2 years (17%) but increased to 19.3% at follow-up. BMI Z increased from 0.3 to 0.38 (p = 0.052) in the N, remained unchanged in the OW, while decreasing significantly in the OB (2.73 to 2.41 p < 0.0001). % WC > 90 th percentile decreased in the OW and OB; 6 MWD was higher in the OW, but the increase in distance overtime was greater among the N. Overall fitness improved, however it was only significant among the N (p = 0.0002). There was a significant increase in food knowledge. We conclude that in spite of a decrease in BMI Z of the OB, an improvement in fitness in the N and food knowledge in all the children, obesity increased at follow-up. This study shows that in school-based obesity programs it is necessary to apply more intense interventions with another type of methodology; otherwise this condition will continue to rise.

  5. 25 CFR 170.137 - What types of activities can a recreation, tourism, and trails program include?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false What types of activities can a recreation, tourism, and... Eligibility Recreation, Tourism and Trails § 170.137 What types of activities can a recreation, tourism, and... may perform under a recreation, tourism, and trails program: (1) Transportation planning for...

  6. 25 CFR 170.137 - What types of activities can a recreation, tourism, and trails program include?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true What types of activities can a recreation, tourism, and... Eligibility Recreation, Tourism and Trails § 170.137 What types of activities can a recreation, tourism, and... may perform under a recreation, tourism, and trails program: (1) Transportation planning for...

  7. 25 CFR 170.137 - What types of activities can a recreation, tourism, and trails program include?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false What types of activities can a recreation, tourism, and... Eligibility Recreation, Tourism and Trails § 170.137 What types of activities can a recreation, tourism, and... may perform under a recreation, tourism, and trails program: (1) Transportation planning for...

  8. 25 CFR 170.137 - What types of activities can a recreation, tourism, and trails program include?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false What types of activities can a recreation, tourism, and... Eligibility Recreation, Tourism and Trails § 170.137 What types of activities can a recreation, tourism, and... may perform under a recreation, tourism, and trails program: (1) Transportation planning for...

  9. 25 CFR 170.137 - What types of activities can a recreation, tourism, and trails program include?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false What types of activities can a recreation, tourism, and... Eligibility Recreation, Tourism and Trails § 170.137 What types of activities can a recreation, tourism, and... may perform under a recreation, tourism, and trails program: (1) Transportation planning for...

  10. HEPS Inventory Tool: An Inventory Tool Including Quality Assessment of School Interventions on Healthy Eating and Physical Activity

    ERIC Educational Resources Information Center

    Dadaczynski, Kevin; Paulus, Peter; de Vries, Nanne; de Ruiter, Silvia; Buijs, Goof

    2010-01-01

    The HEPS Inventory Tool aims to support stakeholders working in school health promotion to promote high quality interventions on healthy eating and physical activity. As a tool it provides a step-by-step approach on how to develop a national or regional inventory of existing school based interventions on healthy eating and physical activity. It…

  11. Induction conductivity and natural gamma logs collected in 15 wells at Camp Stanley Storage Activity, Bexar County, Texas

    USGS Publications Warehouse

    Stanton, Gregory P.

    2005-01-01

    The U.S. Geological Survey, in cooperation with the Camp Stanley Storage Activity conducted electromagnetic induction conductivity and natural gamma logging of 15 selected wells on the Camp Stanley Storage Activity, located in northern Bexar County, Texas, during March 28-30, 2005. In late 2004, a helicopter electromagnetic survey was flown of the Camp Stanley Storage Activity as part of a U.S. Geological Survey project to better define subsurface geologic units, the structure, and the catchment area of the Trinity aquifer. The electromagnetic induction conductivity and natural gamma log data in this report were collected to constrain the calculation of resistivity depth sections and to provide subsurface controls for interpretation of the helicopter electromagnetic data collected for the Camp Stanley Storage Activity. Logs were recorded digitally while moving the probe in an upward direction to maintain proper depth control. Logging speed was no greater than 30 feet per minute. During logging, a repeat section of at least 100 feet was recorded to check repeatability of log responses. Several of the wells logged were completed with polyvinyl chloride casing that can be penetrated by electromagnetic induction fields and allows conductivity measurement. However, some wells were constructed with steel centralizers and stainless steel screen that caused spikes on both conductivity and resulting resistivity log curves. These responses are easily recognizable and appear at regular intervals on several logs.

  12. Multi-dimensional construction of a novel active yolk@conductive shell nanofiber web as a self-standing anode for high-performance lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Liu, Hao; Chen, Luyi; Liang, Yeru; Fu, Ruowen; Wu, Dingcai

    2015-11-01

    A novel active yolk@conductive shell nanofiber web with a unique synergistic advantage of various hierarchical nanodimensional objects including the 0D monodisperse SiO2 yolks, the 1D continuous carbon shell and the 3D interconnected non-woven fabric web has been developed by an innovative multi-dimensional construction method, and thus demonstrates excellent electrochemical properties as a self-standing LIB anode.A novel active yolk@conductive shell nanofiber web with a unique synergistic advantage of various hierarchical nanodimensional objects including the 0D monodisperse SiO2 yolks, the 1D continuous carbon shell and the 3D interconnected non-woven fabric web has been developed by an innovative multi-dimensional construction method, and thus demonstrates excellent electrochemical properties as a self-standing LIB anode. Electronic supplementary information (ESI) available: Experimental details and additional information about material characterization. See DOI: 10.1039/c5nr06531c

  13. Electroanalysis of NADH Using Conducting and Redox Active Polymer/Carbon Nanotubes Modified Electrodes-A Review

    PubMed Central

    Kumar, S. Ashok; Chen, Shen-Ming

    2008-01-01

    Past few decades, conducting and redox active polymers play a critical role in the development of transducers for biosensing. It has been evidenced by increasing numerous reports on conducting and redox active polymers incorporated electrodes for assay of biomolcules. This review highlights the potential uses of electrogenerated polymer modified electrodes and polymer/carbon nanotubes composite modified electrodes for electroanalysis of reduced form of nicotinamide adenine dinuceltoide (NADH). In addition, carbon electrodes modified with organic and inorganic materials as modifier have been discussed in detail for the quantification of NADH based on mediator or mediator-less methods.

  14. Effects of restricted feeding on daily fluctuations of hepatic functions including p450 monooxygenase activities in rats.

    PubMed

    Hirao, Jun; Arakawa, Shingo; Watanabe, Kyoko; Ito, Kazumi; Furukawa, Tadashi

    2006-02-10

    Hepatic P450 monooxygenase activities, assessed by measurement of 7-alkoxycoumarin O-dealkylase (ACD) activities, show obvious daily fluctuations in male rats with high values during the dark period and low values during the light period. We have already confirmed that the ACD activities are controlled by the suprachiasmatic nucleus (SCN), which is well known as the oscillator of circadian rhythm. Recently, it is reported that circadian oscillators exist not only in the SCN but also in peripheral organs. To date, it is unclear which circadian oscillators predominantly drive the daily fluctuations of hepatic ACD activities. To address this question, we examined the effects of restricted feeding, which uncouples the circadian oscillators in the liver from the central pacemaker in the SCN, on the daily fluctuations in hepatic ACD activities in male rats. Here we show that restricted feeding inverts the oscillation phase of the daily fluctuations in hepatic ACD activities. Regarding the hepatic P450 content, there were no fluctuations between the light and dark periods under ad libitum and restricted feeding conditions. Therefore, it is considered that the daily fluctuations in hepatic ACD activities are predominantly driven by the circadian factors in peripheral organs rather than by the oscillator in the SCN directly.

  15. Multi-dimensional construction of a novel active yolk@conductive shell nanofiber web as a self-standing anode for high-performance lithium-ion batteries.

    PubMed

    Liu, Hao; Chen, Luyi; Liang, Yeru; Fu, Ruowen; Wu, Dingcai

    2015-12-21

    A novel active yolk@conductive shell nanofiber web with a unique synergistic advantage of various hierarchical nanodimensional objects including the 0D monodisperse SiO2 yolks, the 1D continuous carbon shell and the 3D interconnected non-woven fabric web has been developed by an innovative multi-dimensional construction method, and thus demonstrates excellent electrochemical properties as a self-standing LIB anode. PMID:26581017

  16. Growth-inhibiting extracellular matrix proteins also inhibit electrical activity by reducing calcium and increasing potassium conductances.

    PubMed

    Vargas, J; De-Miguel, F F

    2009-01-23

    Inhibitionof neurite sprouting and electrical activity by extracellular matrix (ECM) glycoproteins was studied during neurite regeneration by using anterior pagoda (AP) neurons of the leech. Adult isolated neurons were plated in culture inside ganglion capsules, which among many ECM proteins, contain a group of inhibitory peanut lectin- (PNA) binding glycoproteins. These proteins inhibit neurite production and contribute to the formation of a bipolar outgrowth pattern by AP neurons. Addition of PNA lectin to the culture medium to block the inhibitory effects of ECM glycoproteins induced an increase of neurite sprouting, the loss of the bipolar pattern, and also an increase in the amplitude and duration of action potentials evoked by intracellular current injection. PNA lectin had independent effects on neurite sprouting and electrical activity, since there was no correlation between the total neurite length and the amplitude of the action potentials. Moreover, action potentials were increased by the presence of PNA lectin even in neurons that did not grow. The changes induced by PNA lectin on the active conductances underlying the action potentials were estimated by quantitative model simulations. We predict that the increases in the amplitude and duration of the action potential induced by PNA lectin were due to an increase in a calcium conductance and a reduction in the delayed rectifier potassium conductance. Our results suggest that inhibitory ECM glycoproteins may use independent signaling pathways to inhibit neurite sprouting and electrical activity. These proteins affect the action potential by changing the proportion of inward and outward active conductances. PMID:18976697

  17. Antiviral activity of human Vδ2 T-cells against WNV includes both cytolytic and non-cytolytic mechanisms.

    PubMed

    Agrati, Chiara; Castilletti, Concetta; Cimini, Eleonora; Romanelli, Antonella; Lapa, Daniele; Quartu, Serena; Martini, Federico; Capobianchi, Maria Rosaria

    2016-04-01

    West Nile virus (WNV) causes a severe central nervous system infection in humans, primarily in the elderly and immunocompromised subjects. Human γδ T-cells play a critical role in the immune response against viruses, and studies of WNV meningoencephalitis in laboratory mice described a role of γδ T-cells in the protective immune response. Aim of this study was to analyze the cytolytic and non-cytolytic antiviral activity of human Vδ2 T-cells against WNV replication. The anti-WNV activity of soluble factor released by zoledronic acid (ZA)-activated Vδ2 T-cell lines and the cytotoxic capability of Vδ2 T-cell lines against WNV-infected cells were tested in vitro. The activation of Vδ2 T-cell lines was able to inhibit WNV replication through the release of soluble factors. IFN-γ is massively released by activated Vδ2 T-cell lines and is involved in the anti-WNV activity. Moreover, the Vδ2 T-cell lines can efficiently kill WNV-infected cells possibly through perforin-mediated mechanism. Altogether, our results provide insight into the effector functions of human Vδ2 T-cells against WNV. The possibility to target these cells by ZA, a commercially available drug used in humans, could potentially offer a new immunotherapeutic strategy for WNV infection. PMID:27196553

  18. 21 CFR 312.87 - Active monitoring of conduct and evaluation of clinical trials.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... clinical trials. 312.87 Section 312.87 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... and evaluation of clinical trials. For drugs covered under this section, the Commissioner and other agency officials will monitor the progress of the conduct and evaluation of clinical trials and...

  19. 26 CFR 1.355-3 - Active conduct of a trade or business.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    .... Corporation X is engaged in the manufacture and sale of soap and detergents and also owns investment... years, corporation X has conducted a single business of constructing sewage disposal plants and other... construction of a sewage disposal plant in State M, construction equipment, cash, and other tangible assets....

  20. 26 CFR 1.355-3 - Active conduct of a trade or business.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    .... Corporation X is engaged in the manufacture and sale of soap and detergents and also owns investment... years, corporation X has conducted a single business of constructing sewage disposal plants and other... construction of a sewage disposal plant in State M, construction equipment, cash, and other tangible assets....

  1. 26 CFR 1.355-3 - Active conduct of a trade or business.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...), a distribution of stock, or stock and securities, of a controlled corporation qualifies under... conduct of a trade or business immediately after the distribution (section 355(b)(1)(A)), or (ii) Immediately before the distribution, the distributing corporation had no assets other than stock or...

  2. 26 CFR 1.355-3 - Active conduct of a trade or business.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...), a distribution of stock, or stock and securities, of a controlled corporation qualifies under... conduct of a trade or business immediately after the distribution (section 355(b)(1)(A)), or (ii) Immediately before the distribution, the distributing corporation had no assets other than stock or...

  3. 34 CFR 350.32 - What activities must a Rehabilitation Engineering Research Center conduct?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... solve rehabilitation problems and remove environmental barriers through— (i) Planning and conducting...) Demonstrating and disseminating— (i) Innovative models for the delivery to rural and urban areas of cost...-responsive and individual and family-centered innovative models for the delivery, to both rural and...

  4. 78 FR 78788 - Nondiscrimination in Programs or Activities Conducted by the United States Department of Agriculture

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ... of race, color, and national origin. (See 29 Federal Register (FR) 16966, creating 7 CFR part 15... in 1999 (64 FR 66709, Nov 30, 1999). The changes are proposed to clarify the roles and... equal treatment of transgender and other gender nonconforming individuals in USDA's conducted...

  5. A High-Conduction Ge Substituted Li3AsS4 Solid Electrolyte with Exceptional Low Activation Energy

    SciTech Connect

    Sahu, Gayatri; Rangasamy, Ezhiylmurugan; Li, Juchuan; Chen, Yan; An, Ke; Dudney, Nancy J; Liang, Chengdu

    2014-01-01

    Lithium-ion conducting solid electrolytes show potential to enable high-energy-density secondary batteries and offer distinctive safety features as an advantage over traditional liquid electrolytes. Achieving the combination of high ionic conductivity, low activation energy, and outstanding electrochemical stability in crystalline solid electrolytes is a challenge for the synthesis of novel solid electrolytes. Herein we report an exceptionally low activation energy (Ea) and high room temperature superionic conductivity via facile aliovalent substitution of Li3AsS4 by Ge, which increased the conductivity by two orders of magnitude as compared to the parent compound. The composition Li3.334Ge0.334As0.666S4 has a high ionic conductivity of 1.12 mScm-1 at 27oC. Local Li+ hopping in this material is accompanied by distinctive low activation energy Ea of 0.17 eV being the lowest of Li+ solid conductors. Furthermore, this study demonstrates the efficacy of surface passivation of solid electrolyte to achieve compatibility with metallic lithium electrodes.

  6. School Counselors Share Their Favorite Classroom Guidance Activities: Guide to Planning, Conducting, and Processing

    ERIC Educational Resources Information Center

    DeLucia-Waack, J., Ed.; Mercurio, M., Ed.; Colvin, F., Ed.; Korta, S., Ed.; Maertin, K., Ed.; Martin, E., Ed.; Zawadski, L., Ed.

    2014-01-01

    In this book, practicing school counselors have provided more than 60 classroom guidance activities that are presented across the three major ASCA areas in the National Standards for Students: Academic Skills, Personal/Social Skills, and Career Development/College Preparation. Activities are designed to integrate the ASCA Model, Response to…

  7. 34 CFR 350.22 - What activities must a Rehabilitation Research and Training Center conduct?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... DISABILITY AND REHABILITATION RESEARCH PROJECTS AND CENTERS PROGRAM What Rehabilitation Research and Training Centers Does the Secretary Assist? § 350.22 What activities must a Rehabilitation Research and Training... 34 Education 2 2010-07-01 2010-07-01 false What activities must a Rehabilitation Research...

  8. 34 CFR 350.32 - What activities must a Rehabilitation Engineering Research Center conduct?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 2 2011-07-01 2010-07-01 true What activities must a Rehabilitation Engineering... DISABILITY AND REHABILITATION RESEARCH PROJECTS AND CENTERS PROGRAM What Rehabilitation Engineering Research Centers Does the Secretary Assist? § 350.32 What activities must a Rehabilitation Engineering...

  9. 34 CFR 350.22 - What activities must a Rehabilitation Research and Training Center conduct?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 2 2011-07-01 2010-07-01 true What activities must a Rehabilitation Research and... DISABILITY AND REHABILITATION RESEARCH PROJECTS AND CENTERS PROGRAM What Rehabilitation Research and Training Centers Does the Secretary Assist? § 350.22 What activities must a Rehabilitation Research and...

  10. 34 CFR 350.32 - What activities must a Rehabilitation Engineering Research Center conduct?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 2 2012-07-01 2012-07-01 false What activities must a Rehabilitation Engineering... DISABILITY AND REHABILITATION RESEARCH PROJECTS AND CENTERS PROGRAM What Rehabilitation Engineering Research Centers Does the Secretary Assist? § 350.32 What activities must a Rehabilitation Engineering...

  11. 30 CFR 285.800 - How must I conduct my activities to comply with safety and environmental requirements?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., Inspections, and Facility Assessments for Activities Conducted Under SAPs, COPs and GAPs § 285.800 How must I... approved SAP, COP, or GAP, as required under §§ 285.615(c), 285.633(b), or 285.653(c)....

  12. 34 CFR 222.172 - What activities may an LEA conduct with funds received under this program?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false What activities may an LEA conduct with funds received under this program? 222.172 Section 222.172 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION IMPACT AID PROGRAMS...

  13. 30 CFR 285.803 - How must I conduct my approved activities to protect essential fish habitats identified and...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... protect essential fish habitats identified and described under the Magnuson-Stevens Fishery Conservation... fish habitats identified and described under the Magnuson-Stevens Fishery Conservation and Management Act? (a) If, during the conduct of your approved activities, MMS finds that essential fish habitat...

  14. 30 CFR 585.803 - How must I conduct my approved activities to protect essential fish habitats identified and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false How must I conduct my approved activities to protect essential fish habitats identified and described under the Magnuson-Stevens Fishery Conservation and Management Act? 585.803 Section 585.803 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE...

  15. 30 CFR 585.803 - How must I conduct my approved activities to protect essential fish habitats identified and...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false How must I conduct my approved activities to protect essential fish habitats identified and described under the Magnuson-Stevens Fishery Conservation and Management Act? 585.803 Section 585.803 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE...

  16. 30 CFR 585.803 - How must I conduct my approved activities to protect essential fish habitats identified and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false How must I conduct my approved activities to protect essential fish habitats identified and described under the Magnuson-Stevens Fishery Conservation and Management Act? 585.803 Section 585.803 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE...

  17. 30 CFR 585.801 - How must I conduct my approved activities to protect marine mammals, threatened and endangered...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... protect marine mammals, threatened and endangered species, and designated critical habitat? 585.801... endangered species, and designated critical habitat? (a) You must not conduct any activity under your lease or grant that may affect threatened or endangered species or that may affect designated...

  18. 30 CFR 285.801 - How must I conduct my approved activities to protect marine mammals, threatened and endangered...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... protect marine mammals, threatened and endangered species, and designated critical habitat? 285.801... endangered species, and designated critical habitat? (a) You must not conduct any activity under your lease or grant that may affect threatened or endangered species or that may affect designated...

  19. 30 CFR 585.801 - How must I conduct my approved activities to protect marine mammals, threatened and endangered...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... protect marine mammals, threatened and endangered species, and designated critical habitat? 585.801... endangered species, and designated critical habitat? (a) You must not conduct any activity under your lease or grant that may affect threatened or endangered species or that may affect designated...

  20. 30 CFR 585.801 - How must I conduct my approved activities to protect marine mammals, threatened and endangered...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... protect marine mammals, threatened and endangered species, and designated critical habitat? 585.801... endangered species, and designated critical habitat? (a) You must not conduct any activity under your lease or grant that may affect threatened or endangered species or that may affect designated...

  1. 30 CFR 285.801 - How must I conduct my approved activities to protect marine mammals, threatened and endangered...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... protect marine mammals, threatened and endangered species, and designated critical habitat? 285.801... mammals, threatened and endangered species, and designated critical habitat? (a) You must not conduct any activity under your lease or grant that may affect threatened or endangered species or that may...

  2. 30 CFR 280.3 - What requirements must I follow when I conduct prospecting or research activities?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What requirements must I follow when I conduct prospecting or research activities? 280.3 Section 280.3 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE PROSPECTING FOR MINERALS OTHER THAN OIL,...

  3. 30 CFR 280.3 - What requirements must I follow when I conduct prospecting or research activities?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What requirements must I follow when I conduct prospecting or research activities? 280.3 Section 280.3 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE PROSPECTING FOR MINERALS OTHER THAN OIL, GAS, AND SULPHUR ON THE...

  4. 14 CFR 440.11 - Duration of coverage for licensed launch, including suborbital launch, or permitted activities...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... LICENSING FINANCIAL RESPONSIBILITY Financial Responsibility for Licensed and Permitted Activities § 440.11...; modifications. (a) Insurance coverage required under § 440.9, or other form of financial responsibility, shall... recovery; or (ii) The FAA's determination that risk to third parties and Government property as a result...

  5. Activated Notch1 Target Genes during Embryonic Cell Differentiation Depend on the Cellular Context and Include Lineage Determinants and Inhibitors

    PubMed Central

    Meier-Stiegen, Franziska; Schwanbeck, Ralf; Bernoth, Kristina; Martini, Simone; Hieronymus, Thomas; Ruau, David; Zenke, Martin; Just, Ursula

    2010-01-01

    Background Notch receptor signaling controls developmental cell fates in a cell-context dependent manner. Although Notch signaling directly regulates transcription via the RBP-J/CSL DNA binding protein, little is known about the target genes that are directly activated by Notch in the respective tissues. Methodology/Principal Findings To analyze how Notch signaling mediates its context dependent function(s), we utilized a Tamoxifen-inducible system to activate Notch1 in murine embryonic stem cells at different stages of mesodermal differentiation and performed global transcriptional analyses. We find that the majority of genes regulated by Notch1 are unique for the cell type and vary widely dependent on other signals. We further show that Notch1 signaling regulates expression of genes playing key roles in cell differentiation, cell cycle control and apoptosis in a context dependent manner. In addition to the known Notch1 targets of the Hes and Hey families of transcriptional repressors, Notch1 activates the expression of regulatory transcription factors such as Sox9, Pax6, Runx1, Myf5 and Id proteins that are critically involved in lineage decisions in the absence of protein synthesis. Conclusion/Significance We suggest that Notch signaling determines lineage decisions and expansion of stem cells by directly activating both key lineage specific transcription factors and their repressors (Id and Hes/Hey proteins) and propose a model by which Notch signaling regulates cell fate commitment and self renewal in dependence of the intrinsic and extrinsic cellular context. PMID:20628604

  6. Urinary bladder instability induced by selective suppression of the murine small conductance calcium-activated potassium (SK3) channel

    PubMed Central

    Herrera, Gerald M; Pozo, Maria J; Zvara, Peter; Petkov, Georgi V; Bond, Chris T; Adelman, John P; Nelson, Mark T

    2003-01-01

    Small conductance, calcium-activated potassium (SK) channels have an important role in determining the excitability and contractility of urinary bladder smooth muscle. Here, the role of the SK isoform SK3 was examined by altering expression levels of the SK3 gene using a mouse model that conditionally overexpresses SK3 channels (SK3T/T). Prominent SK3 immunostaining was found in both the smooth muscle (detrusor) and urothelium layers of the urinary bladder. SK currents were elevated 2.4-fold in isolated myocytes from SK3T/T mice. Selective suppression of SK3 expression by dietary doxycycline (DOX) decreased SK current density in isolated myocytes, increased phasic contractions of isolated urinary bladder smooth muscle strips and exposed high affinity effects of the blocker apamin of the SK isoforms (SK1–3), suggesting an additional participation from SK2 channels. The role of SK3 channels in urinary bladder function was assessed using cystometry in conscious, freely moving mice. The urinary bladders of SK3T/T had significantly greater bladder capacity, and urine output exceeded the infused saline volume. Suppression of SK3 channel expression did not alter filling pressure, threshold pressure or bladder capacity, but micturition pressure was elevated compared to control mice. However, SK3 suppression did eliminate excess urine production and caused a marked increase in non-voiding contractions. The ability to examine bladder function in mice in which SK3 channel expression is selectively altered reveals that these channels have a significant role in the control of non-voiding contractions in vivo. Activation of these channels may be a therapeutic approach for management of non-voiding contractions, a condition which characterizes many types of urinary bladder dysfunctions including urinary incontinence. PMID:12813145

  7. Inhibition of vascular calcification by block of intermediate conductance calcium-activated potassium channels with TRAM-34.

    PubMed

    Freise, Christian; Querfeld, Uwe

    2014-07-01

    Vascular calcifications are a hallmark of advanced cardiovascular disease in patients with chronic kidney disease. A key event is the transition of contractile vascular smooth muscle cells (VSMC) into an osteoblast-like phenotype, promoting a coordinated process of vascular remodeling resembling bone mineralization. Intermediate-conductance calcium-activated potassium channels (KCa3.1) are expressed in various tissues including VSMC. Aiming for novel therapeutic targets in vascular calcification, we here studied effects of KCa3.1-inhibition on VSMC calcification by the specific KCa3.1 inhibitor TRAM-34. Calcification in the murine VSMC cell line MOVAS-1 and primary rat VSMC was induced by calcification medium (CM) containing elevated levels of PO4(3-) and Ca(2+). Cell signaling, calcification markers, and release of nitric oxide and alkaline phosphatase were assessed by luciferase reporter plasmids, RT-PCR and specific enzymatic assays, respectively. KCa3.1 gene silencing was achieved by siRNA experiments. TRAM-34 at 10nmol/l, decreased CM-induced calcification and induced NO release of VSMC accompanied by decreased TGF-β signaling. The CM-induced mRNA expressions of osterix, osteocalcin, matrix-metalloproteinases (MMP)-2/-9 were reduced by TRAM-34 while osteopontin expression was increased. Further, TRAM-34 attenuated the CM- and TNF-α-induced activation of NF-κB and reduced the release of MMP-2/-9 by VSMC. Finally, TRAM-34 abrogated CM-induced apoptosis and KCa3.1 gene silencing protected VSMC from CM-induced onset of calcification. In summary, TRAM-34 interferes with calcification relevant signaling of NF-κB and TGF-β thereby blocking the phenotypic transition/calcification of VSMC. We conclude that the results provide a rationale for further studies regarding a possible therapeutic role of KCa3.1 inhibition by TRAM-34 or other inhibitors in vascular calcification.

  8. Enhancement of electrical conductivity and electrochemical activity of hydrogenated amorphous carbon by incorporating boron atoms

    NASA Astrophysics Data System (ADS)

    Naragino, Hiroshi; Yoshinaga, Kohsuke; Nakahara, Akira; Tanaka, Sakuya; Honda, Kensuke

    2013-06-01

    Conductive boron-doped hydrogenated amorphous carbon (B-DLC) thin films were successfully synthesized with RF plasma-enhanced CVD method. By incorporating boron atoms in amorphous carbon, conduction types were changed from n- to p-type, and volume resistivity was decreased from 30.4 (non-doped) to 6.36 × 10-2 Ω cm (B/C = 2.500 atom%). B-DLC film with sp2/(sp2 + sp3) carbons of 75 atom% exhibited high resistance to electrochemically-induced corrosion in strong acid solution. Furthermore, it was clarified that boron atoms in DLC could enhance kinetics of hydrogen evolution during water electrolysis at B-DLC surface. B-DLC is, therefore, a promising electrode material for hydrogen production by increasing the concentration of boron atoms in B-DLC and enhancing the reactivity of H2 evolution.

  9. A summary of lessons learned activities conducted at the OECD Halden Reactor Project

    SciTech Connect

    Hallbert, B.P.

    1997-02-01

    A series of lessons learned studies have been conducted at the OECD Halden Reactor Project. The purpose of these lessons learned reports are to summarize knowledge and experience gained across a number of research project. This paper presents a summary of main issues addressed in four of these lessons learned projects. These are concerned with software development and quality assurance, software reliability, methods for test and evaluation of developed systems, and the evaluation of system design features.

  10. Taurine and glycine activate the same Cl- conductance in substantia nigra dopamine neurones.

    PubMed

    Häusser, M A; Yung, W H; Lacey, M G

    1992-01-31

    Intracellular recordings were made from substantia nigra dopamine neurones in a rat brain slice preparation. Spontaneous firing in these cells was reversibly inhibited by taurine applied by superfusion (300 microM-20 mM) or by focal pressure ejection. Neurones recorded with electrodes filled with KCl were depolarised at resting potential by taurine; the taurine depolarisation reversed polarity at -36.6 +/- 1.0 mV (7 cells). When electrodes filled with K-acetate or K-methyl sulphate were used, taurine caused a hyperpolarisation which reversed at -74.2 +/- 3.8 mV (9 cells). These effects of taurine were accompanied by a fall in input resistance or, in voltage clamp, an increase in conductance. Taurine thus appeared to increase membrane chloride conductance. The effect of taurine persisted in tetrodotoxin, 0-Ca2+/10 mM Mg2+, and bicuculline, but was blocked by strychnine (10 microM). Maximal responses to either taurine or glycine occluded responses to the other amino acid. Taurine therefore acts directly on dopamine neurones in the substantia nigra to increase the same membrane Cl- conductance as that mediating the action of glycine. Taurine may also act at the same recognition site as glycine in these cells.

  11. High power density aqueous hybrid supercapacitor combining activated carbon and highly conductive spinel cobalt oxide

    NASA Astrophysics Data System (ADS)

    Godillot, G.; Taberna, P.-L.; Daffos, B.; Simon, P.; Delmas, C.; Guerlou-Demourgues, L.

    2016-11-01

    The remarkable electrochemical behavior of complete activated carbon/cobalt oxide cells is reported in the present work. Among the various weight ratios between the positive and negative electrodes evaluated, the best features are obtained with an overcapacitive cobalt oxide electrode. The energy densities obtained by this system (20 Wh kg-1 for a power density of 209 W kg-1) are twice higher than those measured for a activated carbon/activated carbon symmetric cell, in the same operating conditions. With discharge capacities around 62 F g-1, this system is among the best ones reported in the literature for this category.

  12. Weight management including dietary and physical activity advice provided by Australian physiotherapists: a pilot cross-sectional survey.

    PubMed

    Snodgrass, Suzanne J; Carter, Amy E; Guest, Maya; Collins, Clare E; James, Carole; Kable, Ashley K; Ashby, Samantha E; Plotnikoff, Ronald C

    2014-08-01

    Physiotherapists may have an impact on obesity prevention and treatment by providing nutrition and physical activity advice to overweight or obese clients; yet little is known about physiotherapists' beliefs and practices related to client weight management. The aim of this pilot study was to determine the practices, beliefs, attitudes and knowledge of physiotherapists regarding the provision of weight management advice to overweight or obese clients. Physiotherapists (n = 65) working in multiple practice settings completed a self-administered questionnaire. Logistic regression determined factors associated with the provision of dietary and physical activity advice for weight management. The majority of physiotherapists (n = 53 [81.5%]) believed providing weight management advice was within their scope of practice, yet only a minority had received training during their professional entry level education (n = 13 [20%]) or through professional development (n = 7 [11%]). Most physiotherapists (n = 55 [84.6%]) provided physical activity advice for weight management, but a minority (n = 27 [41.5%]) provided dietary advice. Having received training in weight management during their professional entry level education was associated with providing dietary advice (Odds ratio 8.8, 95% confidence interval 2.0-38.9, p = 0.004). Training in weight management may increase the likelihood of physiotherapists providing dietary advice, improving physiotherapists' management of obesity.

  13. The MRX Complex Ensures NHEJ Fidelity through Multiple Pathways Including Xrs2-FHA–Dependent Tel1 Activation

    PubMed Central

    Iwasaki, Daichi; Hayashihara, Kayoko; Shima, Hiroki; Higashide, Mika; Terasawa, Masahiro; Gasser, Susan M.; Shinohara, Miki

    2016-01-01

    Because DNA double-strand breaks (DSBs) are one of the most cytotoxic DNA lesions and often cause genomic instability, precise repair of DSBs is vital for the maintenance of genomic stability. Xrs2/Nbs1 is a multi-functional regulatory subunit of the Mre11-Rad50-Xrs2/Nbs1 (MRX/N) complex, and its function is critical for the primary step of DSB repair, whether by homologous recombination (HR) or non-homologous end joining. In human NBS1, mutations result truncation of the N-terminus region, which contains a forkhead-associated (FHA) domain, cause Nijmegen breakage syndrome. Here we show that the Xrs2 FHA domain of budding yeast is required both to suppress the imprecise repair of DSBs and to promote the robust activation of Tel1 in the DNA damage response pathway. The role of the Xrs2 FHA domain in Tel1 activation was independent of the Tel1-binding activity of the Xrs2 C terminus, which mediates Tel1 recruitment to DSB ends. Both the Xrs2 FHA domain and Tel1 were required for the timely removal of the Ku complex from DSB ends, which correlates with a reduced frequency of imprecise end-joining. Thus, the Xrs2 FHA domain and Tel1 kinase work in a coordinated manner to maintain DSB repair fidelity. PMID:26990569

  14. The IKAROS Interaction with a Complex Including Chromatin Remodeling and Transcription Elongation Activities Is Required for Hematopoiesis

    PubMed Central

    Bottardi, Stefania; Mavoungou, Lionel; Pak, Helen; Daou, Salima; Bourgoin, Vincent; Lakehal, Yahia A.; Affar, El Bachir; Milot, Eric

    2014-01-01

    IKAROS is a critical regulator of hematopoietic cell fate and its dynamic expression pattern is required for proper hematopoiesis. In collaboration with the Nucleosome Remodeling and Deacetylase (NuRD) complex, it promotes gene repression and activation. It remains to be clarified how IKAROS can support transcription activation while being associated with the HDAC-containing complex NuRD. IKAROS also binds to the Positive-Transcription Elongation Factor b (P-TEFb) at gene promoters. Here, we demonstrate that NuRD and P-TEFb are assembled in a complex that can be recruited to specific genes by IKAROS. The expression level of IKAROS influences the recruitment of the NuRD-P-TEFb complex to gene regulatory regions and facilitates transcription elongation by transferring the Protein Phosphatase 1α (PP1α), an IKAROS-binding protein and P-TEFb activator, to CDK9. We show that an IKAROS mutant that is unable to bind PP1α cannot sustain gene expression and impedes normal differentiation of IkNULL hematopoietic progenitors. Finally, the knock-down of the NuRD subunit Mi2 reveals that the occupancy of the NuRD complex at transcribed regions of genes favors the relief of POL II promoter-proximal pausing and thereby, promotes transcription elongation. PMID:25474253

  15. Simultaneous BVI noise and vibration reduction in rotorcraft using actively-controlled flaps and including performance considerations

    NASA Astrophysics Data System (ADS)

    Patt, Daniel A.

    This work presents the development and application of an active control approach for reduction of both vibration and noise induced by helicopter rotor blade vortex interaction (BVI). Control is implemented through single or dual actively controlled flaps (ACFs) on each blade. Low-speed helicopter flight is prone to severe BVI, resulting in elevated vibration and noise levels. Existing research has suggested that when some form of active control is used to reduce vibration, noise will increase and vice versa. The present research achieves simultaneous reduction of noise and vibration, and also investigates the physical sources of the observed reduction. The initial portion of this work focused on developing a tool for simulating helicopter noise and vibrations in the BVI flight regime. A method for predicting compressible unsteady blade surface pressure distribution on rotor blades was developed and combined with an enhanced free-wake model and an acoustic prediction tool with provisions for blade flexibility. These elements were incorporated within an aeroelastic analysis featuring fully coupled flap-lag-torsional blade dynamics. Subsequently, control algorithms were developed that were effective for reducing noise and vibration even in the nonlinear BVI flight regime; saturation limits were incorporated constraining flap deflections to specified limits. The resulting simulation was also validated with a wide range of experimental data, achieving excellent correlation. Finally, a number of active control studies were performed. Multi-component vibration reductions of 40--80% could be achieved, while incurring a small noise penalty. Noise was reduced using an onboard feedback microphone; reductions of 4--10 dB on the advancing side were observed on a plane beneath the rotor when using dual flaps. Finally, simultaneous noise and vibration reduction was studied. A reduction of about 5 dB in noise on the advancing side combined with a 60% reduction in vibration was

  16. Thrombin conducts epithelial‑mesenchymal transition via protease‑activated receptor‑1 in human gastric cancer.

    PubMed

    Otsuki, Tadayoshi; Fujimoto, Daisuke; Hirono, Yasuo; Goi, Takanori; Yamaguchi, Akio

    2014-12-01

    Epithelial-mesenchymal transition (EMT) is thought to be a key step for cancer metastasis. Using an immunohistochemical approach with gastric carcinoma tissue, we found the expression of protease-activated receptor-1 (PAR1), along with a metalloproteinase known to activate PAR1, were associated with poorer prognosis, compared with expression-negative tumors, and activated PAR1 promotes gastric cancer cell invasion and proliferation in vivo. In this study we observed EMT induction by the PAR1 agonist α-thrombin, in human gastric cell lines stably expressing PAR1. We investigated α-thrombin-induced changes in the cell forms of pcDNA3.1-MKN45 (MKN45/Mock), pcDNA3.1‑PAR1 transfected MKN45 (MKN45/PAR1), and MKN74. Expression levels of epithelial and mesenchymal markers as well as the distribution of transcriptional factors of E-cadherin in the cytoplasm and nucleus were also noted in these cell lines. We observed α-thrombin-induced morphological changes in MKN45/PAR1 and MKN74 cells. Western blotting and immunohistochemistry of these cells indicated a fall in the expression level of E-cadherin and an increase in fibronectin expression after 48 h. PAR1 activation also induced significant increases in nuclear levels of the Snail which is a repressor of E-cadherin gene expression. We found EMT in gastric cancer cell lines that underwent α-thrombin-induced PAR1 activation. PMID:25231630

  17. 40 CFR 725.239 - Use of specific microorganisms in activities conducted outside a structure.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... sequences, and restriction enzyme sites. (D) The vector nucleotide sequences needed for vector transfer. (E... material, including linkers, homopolymers, adaptors, transposons, insertion sequences, and restriction enzyme sites. (D) The vector nucleotide sequences needed for vector transfer. (E) The vector...

  18. 40 CFR 725.239 - Use of specific microorganisms in activities conducted outside a structure.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... sequences, and restriction enzyme sites. (D) The vector nucleotide sequences needed for vector transfer. (E... material, including linkers, homopolymers, adaptors, transposons, insertion sequences, and restriction enzyme sites. (D) The vector nucleotide sequences needed for vector transfer. (E) The vector...

  19. 40 CFR 725.239 - Use of specific microorganisms in activities conducted outside a structure.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... sequences, and restriction enzyme sites. (D) The vector nucleotide sequences needed for vector transfer. (E... material, including linkers, homopolymers, adaptors, transposons, insertion sequences, and restriction enzyme sites. (D) The vector nucleotide sequences needed for vector transfer. (E) The vector...

  20. 40 CFR 725.239 - Use of specific microorganisms in activities conducted outside a structure.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... sequences, and restriction enzyme sites. (D) The vector nucleotide sequences needed for vector transfer. (E... material, including linkers, homopolymers, adaptors, transposons, insertion sequences, and restriction enzyme sites. (D) The vector nucleotide sequences needed for vector transfer. (E) The vector...

  1. 40 CFR 725.239 - Use of specific microorganisms in activities conducted outside a structure.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... sequences, and restriction enzyme sites. (D) The vector nucleotide sequences needed for vector transfer. (E... material, including linkers, homopolymers, adaptors, transposons, insertion sequences, and restriction enzyme sites. (D) The vector nucleotide sequences needed for vector transfer. (E) The vector...

  2. Amoxapine inhibition of GABA-stimulated chloride conductance: Investigations of potential sites of activity

    SciTech Connect

    Ikeda, M.; Knapp, R.J.; Yamamura, H.I. ); Malatynska, E. )

    1989-01-01

    Amoxapine inhibits GABA-stimulated chloride conductance by acting on the GABA{sub A}-receptor chloride-ionophore complex which can be studied using membrane vesicles prepared from rat cerebral cortex. Amoxapine produces a right shift in the GABA concentration-response curve for the stimulation of {sup 36}Cl{sup {minus}} uptake into these vesicles with no apparent change in the maximum response. Schild analysis of these data gave a pA{sub 2} value of 5.52 with a slope of 0.79. Amoxapine inhibits the binding of the GABA{sub A} receptor selective antagonist ({sup 3}H)SR 95531 with an IC{sub 50} value of 3.45 {mu}M and a pseudo Hill coefficient of 0.83. In contrast, 10 {mu}M amoxapine inhibits ({sup 3}H) flunitrazepam binding by less than 25% while the benzodiazepine antagonist Ro 15-1788 reduces the amoxapine inhibition of GABA-stimulated chloride conductance only at high concentrations.

  3. The Influence of Organized Physical Activity (including Gymnastics) on Young Adult Skeletal Traits: Is Maturity Phase Important?

    PubMed Central

    Bernardoni, Brittney; Scerpella, Tamara A.; Rosenbaum, Paula F.; Kanaley, Jill A.; Raab, Lindsay N.; Li, Quefeng; Wang, Sijian; Dowthwaite, Jodi N.

    2015-01-01

    We prospectively evaluated adolescent organized physical activity (PA) as a factor in adult female bone traits. Annual DXA scans accompanied semi-annual records of anthropometry, maturity and PA for 42 participants in this preliminary analysis (criteria: appropriately timed DXA scans at ~1 year pre-menarche [predictor] and ~5 years post-menarche [dependent variable]). Regression analysis evaluated total adolescent inter-scan PA and PA over 3 maturity sub-phases as predictors of young adult bone outcomes: 1) bone mineral content (BMC), geometry and strength indices at non-dominant distal radius and femoral neck; 2) sub-head BMC; 3) lumbar spine BMC. Analyses accounted for baseline gynecological age (years pre- or post-menarche), baseline bone status, adult body size and inter-scan body size change. Gymnastics training was evaluated as a potentially independent predictor, but did not improve models for any outcomes (p<0.07). Pre-menarcheal bone traits were strong predictors of most adult outcomes (semi-partial r2 = 0.21-0.59, p≤0.001). Adult 1/3 radius and sub-head BMC were predicted by both total PA and PA 1-3 years post-menarche (p<0.03). PA 3-5 years post-menarche predicted femoral narrow neck width, endosteal diameter and buckling ratio (p<0.05). Thus, participation in organized physical activity programs throughout middle and high school may reduce lifetime fracture risk in females. PMID:25386845

  4. The Influence of Organized Physical Activity (Including Gymnastics) on Young Adult Skeletal Traits: Is Maturity Phase Important?

    PubMed

    Bernardoni, Brittney; Scerpella, Tamara A; Rosenbaum, Paula F; Kanaley, Jill A; Raab, Lindsay N; Li, Quefeng; Wang, Sijian; Dowthwaite, Jodi N

    2015-05-01

    We prospectively evaluated adolescent organized physical activity (PA) as a factor in adult female bone traits. Annual DXA scans accompanied semiannual records of anthropometry, maturity, and PA for 42 participants in this preliminary analysis (criteria: appropriately timed DXA scans at ~1 year premenarche [predictor] and ~5 years postmenarche [dependent variable]). Regression analysis evaluated total adolescent interscan PA and PA over 3 maturity subphases as predictors of young adult bone outcomes: 1) bone mineral content (BMC), geometry, and strength indices at nondominant distal radius and femoral neck; 2) subhead BMC; 3) lumbar spine BMC. Analyses accounted for baseline gynecological age (years pre- or postmenarche), baseline bone status, adult body size and interscan body size change. Gymnastics training was evaluated as a potentially independent predictor, but did not improve models for any outcomes (p > .07). Premenarcheal bone traits were strong predictors of most adult outcomes (semipartial r2 = .21-0.59, p ≤ .001). Adult 1/3 radius and subhead BMC were predicted by both total PA and PA 1-3 years postmenarche (p < .03). PA 3-5 years postmenarche predicted femoral narrow neck width, endosteal diameter, and buckling ratio (p < .05). Thus, participation in organized physical activity programs throughout middle and high school may reduce lifetime fracture risk in females. PMID:25386845

  5. Health education activities conducted by physiotherapy students on field trips to rural areas: a case study.

    PubMed

    Boucaut, R

    1998-11-01

    Field trips to country communities have formed part of the final year physiotherapy undergraduate curriculum at the University of South Australia since 1995. These trips have aimed to give students an experience in primary health care. This paper evaluates these activities within the framework of the health promotion model from the perspective of those involved and evaluates feedback from these people. The activities met four of the five criteria of the health promotion model to some degree. Evaluation from all those participating has been mainly positive, with some aspects of organisation of the field trips requiring improvement. All involved felt they had gained benefits from the field trips; however, further work is needed to align the activities with local health promotion infrastructure.

  6. Conducting polymer based active catheter for minimally invasive interventions inside arteries.

    PubMed

    Shoa, Tina; Madden, John D; Fekri, Niloofar; Munce, Nigel R; Yang, Victor X D

    2008-01-01

    An active catheter intended for controllable intravascular maneuvers is presented and initial experimental results are shown. A commercial catheter is coated with polypyrrole and laser micromachined into electrodes, which are electrochemically activated, leading to bending of the catheter. The catheter's electro-chemo-mechanical properties are theoretically modeled to design the first prototype device, and used to predict an optimal polypyrrole thickness for the desired degree of bending within approximately 30 seconds. We compared the experimental result of catheter bending to the theoretical model with estimated electrochemical strain, showing reasonable agreement. Finally, we used the model to design an encapsulated catheter with polypyrrole actuation for improved intravascular compatibility and performance.

  7. Metformin Restores Intermediate-Conductance Calcium-Activated K⁺ Channel- and Small-Conductance Calcium-Activated K⁺ Channel-Mediated Vasodilatation Impaired by Advanced Glycation End Products in Rat Mesenteric Artery. [Corrected].

    PubMed

    Zhao, Li-Mei; Wang, Yan; Yang, Yong; Guo, Rong; Wang, Nan-Ping; Deng, Xiu-Ling

    2014-11-01

    The present study was designed to investigate the effect of metformin on the impairment of intermediate-conductance and small-conductance Ca(2+)-activated potassium channels (IKCa and SKCa)-mediated relaxation in diabetes and the underlying mechanism. The endothelial vasodilatation function of mesenteric arteries was assessed with the use of wire myography. Expression levels of IKCa and SKCa and phosphorylated Thr(172) of AMP-activated protein kinase (AMPK) were measured using Western blot technology. The channel activity was observed using a whole-cell patch voltage clamp. Reactive oxygen species (ROS) were measured using dihydroethidium and 2',7'-dichlorofluorescein diacetate. Metformin restored the impairment of IKCa- and SKCa-mediated vasodilatation in mesenteric arteries from streptozotocin-induced type 2 diabetic rats and that from normal rats incubated with advanced glycation end products (AGEs) for 3 hours. In cultured human umbilical vein endothelial cells (HUVECs), 1 μM metformin reversed AGE-induced increase of ROS and attenuated AGE- and H2O2- induced downregulation of IKCa and SKCa after long-term incubation (>24 hours). Short-term treatment (3 hours) with 1 μM metformin reversed the decrease of IKCa and SKCa currents induced by AGE incubation for 3 hours without changing the channel expression or the AMPK activation in HUVECs. These results are the first to demonstrate that metformin restored IKCa- and SKCa-mediated vasodilatation impaired by AGEs in rat mesenteric artery, in which the upregulation of channel activity and protein expression is likely involved.

  8. New Pyrrole Derivatives with Potent Tubulin Polymerization Inhibiting Activity As Anticancer Agents Including Hedgehog-Dependent Cancer

    PubMed Central

    La Regina, Giuseppe; Bai, Ruoli; Coluccia, Antonio; Famiglini, Valeria; Pelliccia, Sveva; Passacantilli, Sara; Mazzoccoli, Carmela; Ruggieri, Vitalba; Sisinni, Lorenza; Bolognesi, Alessio; Rensen, Whilelmina Maria; Miele, Andrea; Nalli, Marianna; Alfonsi, Romina; Di Marcotullio, Lucia; Gulino, Alberto; Brancale, Andrea; Novellino, Ettore; Dondio, Giulio; Vultaggio, Stefania; Varasi, Mario; Mercurio, Ciro; Hamel, Ernest; Lavia, Patrizia; Silvestri, Romano

    2014-01-01

    We synthesized 3-aroyl-1-arylpyrrole (ARAP) derivatives as potential anticancer agents having different substituents at the pendant 1-phenyl ring. Both the 1-phenyl ring and 3-(3,4,5-trimethoxyphenyl)carbonyl moieties were mandatory to achieve potent inhibition of tubulin polymerization, binding of colchicine to tubulin, and cancer cell growth. ARAP 22 showed strong inhibition of the P-glycoprotein-overexpressing NCI-ADR-RES and Messa/Dx5MDR cell lines. Compounds 22 and 27 suppressed in vitro the Hedgehog signaling pathway, strongly reducing luciferase activity in SAG treated NIH3T3 Shh-Light II cells, and inhibited the growth of medulloblastoma D283 cells at nanomolar concentrations. ARAPs 22 and 27 represent a new potent class of tubulin polymerization and cancer cell growth inhibitors with the potential to inhibit the Hedgehog signaling pathway. PMID:25025991

  9. 40 CFR 725.235 - Conditions of exemption for activities conducted inside a structure.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... MICROORGANISMS Exemptions for Research and Development Activities § 725.235 Conditions of exemption for... be associated with the microorganism: (i) Information in its possession or control concerning any significant adverse reaction of persons exposed to the microorganism which may reasonably be associated...

  10. 15 CFR 917.42 - Categories of support available for the conducting of Sea Grant activities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., quality education programs in marine areas, establishment of interdisciplinary research teams, and... recipient maintains a high level of quality and relevance in its activities. Project funding is made generally for a single item of research, education and training, or advisory service, but may be...

  11. Pre-Launch Risk Reduction Activities Conducted at KSC for the International Space Station

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, Paul

    2011-01-01

    In the development of any large scale space-based multi-piece assembly effort, planning must include provisions for testing and verification; not only of the individual pieces but also of the pieces together. Without such testing on the ground, the risk to cost, schedule and technical performance increases substantially. This paper will review the efforts undertaken by the International Space Station (ISS), including the International Partners, during the pre-launch phase, primarily at KSC, to reduce the risks associated with the on-orbit assembly and operation of the ISS.

  12. Short-Range Temporal Interactions in Sleep; Hippocampal Spike Avalanches Support a Large Milieu of Sequential Activity Including Replay.

    PubMed

    Mahoney, J Matthew; Titiz, Ali S; Hernan, Amanda E; Scott, Rod C

    2016-01-01

    Hippocampal neural systems consolidate multiple complex behaviors into memory. However, the temporal structure of neural firing supporting complex memory consolidation is unknown. Replay of hippocampal place cells during sleep supports the view that a simple repetitive behavior modifies sleep firing dynamics, but does not explain how multiple episodes could be integrated into associative networks for recollection during future cognition. Here we decode sequential firing structure within spike avalanches of all pyramidal cells recorded in sleeping rats after running in a circular track. We find that short sequences that combine into multiple long sequences capture the majority of the sequential structure during sleep, including replay of hippocampal place cells. The ensemble, however, is not optimized for maximally producing the behavior-enriched episode. Thus behavioral programming of sequential correlations occurs at the level of short-range interactions, not whole behavioral sequences and these short sequences are assembled into a large and complex milieu that could support complex memory consolidation.

  13. Short-Range Temporal Interactions in Sleep; Hippocampal Spike Avalanches Support a Large Milieu of Sequential Activity Including Replay.

    PubMed

    Mahoney, J Matthew; Titiz, Ali S; Hernan, Amanda E; Scott, Rod C

    2016-01-01

    Hippocampal neural systems consolidate multiple complex behaviors into memory. However, the temporal structure of neural firing supporting complex memory consolidation is unknown. Replay of hippocampal place cells during sleep supports the view that a simple repetitive behavior modifies sleep firing dynamics, but does not explain how multiple episodes could be integrated into associative networks for recollection during future cognition. Here we decode sequential firing structure within spike avalanches of all pyramidal cells recorded in sleeping rats after running in a circular track. We find that short sequences that combine into multiple long sequences capture the majority of the sequential structure during sleep, including replay of hippocampal place cells. The ensemble, however, is not optimized for maximally producing the behavior-enriched episode. Thus behavioral programming of sequential correlations occurs at the level of short-range interactions, not whole behavioral sequences and these short sequences are assembled into a large and complex milieu that could support complex memory consolidation. PMID:26866597

  14. Short-Range Temporal Interactions in Sleep; Hippocampal Spike Avalanches Support a Large Milieu of Sequential Activity Including Replay

    PubMed Central

    Mahoney, J. Matthew; Titiz, Ali S.; Hernan, Amanda E.; Scott, Rod C.

    2016-01-01

    Hippocampal neural systems consolidate multiple complex behaviors into memory. However, the temporal structure of neural firing supporting complex memory consolidation is unknown. Replay of hippocampal place cells during sleep supports the view that a simple repetitive behavior modifies sleep firing dynamics, but does not explain how multiple episodes could be integrated into associative networks for recollection during future cognition. Here we decode sequential firing structure within spike avalanches of all pyramidal cells recorded in sleeping rats after running in a circular track. We find that short sequences that combine into multiple long sequences capture the majority of the sequential structure during sleep, including replay of hippocampal place cells. The ensemble, however, is not optimized for maximally producing the behavior-enriched episode. Thus behavioral programming of sequential correlations occurs at the level of short-range interactions, not whole behavioral sequences and these short sequences are assembled into a large and complex milieu that could support complex memory consolidation. PMID:26866597

  15. Product and rate determinations with chemically activated nucleotides in the presence of various prebiotic materials, including other mono- and polynucleotides

    NASA Technical Reports Server (NTRS)

    Kanavarioti, A.; Alberas, D. J.; Rosenbach, M. T.; Bernasconi, C. F.; Chang, S.

    1991-01-01

    We are investigating the reactions of ImpN's in the presence of a number of prebiotically plausible materials, such as metal ions, phosphate, amines and other nucleotides and hope to learn more about the stability/reactivity of ImpN's in a prebiotic aqueous environment. We find that, in the presence of phosphate, ImpN's form substantial amounts of diphosphate nucleotides. These diphosphate nucleotides are not very good substrates for template directed reactions, but are chemically activated and are known to revert to the phosphoimidazolides in the presence of imidazole under solid state conditions. With respect to our studies of the oligomerization reaction, the determination of the dimerization rate constant of a specific ImpN (guanosine 5'-phospho 2 methylimidazolide) both in the absence and the presence of the template leads to the conclusion that at 37 C the dimerization is not template directed, although the subsequent polymerization steps are. In other words, this specific polynucleotide synthesizing system favors the elongation of oligonucleotides as compared with the formation of dimers and trimers. This favoring of the synthesis of long as opposed to short oligonucleotides may be regarded as a rudimentary example of natural selection at the molecular level.

  16. A comparison of methods of assessment of body composition including neutron activation analysis of total body nitrogen.

    PubMed

    Lukaski, H C; Mendez, J; Buskirk, E R; Cohn, S H

    1981-08-01

    Fourteen healthy men underwent determinations of total body nitrogen (TBN) by prompt gamma neutron activation analysis and total body potassium (TBK) by whole body counting to estimate the muscle and nonmuscle components of the fat-free body mass (FFBM) and their protein contents. Comparison of FFBM estimated from TBN and TBK (60.6 +/- 6.9 kg, mean +/- SD), densitometry (62.3 +/- 7.1 kg), TBK alone (62.2 +/- 8.0 kg) and TBW (63.9 +/- 7.8 kg) showed no differences among the techniques. Similarly, there were neither differences in fat mass nor percent body fat among the methods. Analysis of the chemical composition of FFBM of this group showed TBK/FFBM = 62.6 +/- 2.3 mEq/kg, TBW/FFBM = 74.6 +/- 0.2%, TBN/FFBM = 32.74 +/- 1.09 g/kg, protein/FFBM = 20.5+/- 0.7%. The calculated mineral content of the FFBM was 6.4%. These values are strikingly similar to the values calculated by direct chemical analysis. It was concluded that the combined TBN-TBK method is a valid technique for estimating body composition in man.

  17. Cystic fibrosis transmembrane conductance regulator activation by the solvent ethanol: implications for topical drug delivery

    PubMed Central

    Cho, Do-Yeon; Skinner, Daniel; Zhang, Shaoyan; Fortenberry, James; Sorscher, Eric J.; Dean, Nichole R.; Woodworth, Bradford A.

    2016-01-01

    Background Decreased CFTR-mediated chloride (Cl) secretion across mucosal surfaces contributes to the development of airway disease by depleting airway surface liquid, increasing mucus viscosity and adhesion, and consequently hindering mucociliary clearance. We serendipitously discovered during testing of drugs solubilized in low concentrations ethanol (0.25%, 43mM) that the control vehicle produced robust activation of CFTR-mediated Cl− transport. The objective of the current study is to investigate low concentrations ethanol for effects on Cl− secretion and ciliary beat frequency (CBF). Methods Wild type (WT) and transgenic CFTR−/− primary murine nasoseptal epithelial (MNSE) and WT and F508del/F508del human sinonasal epithelial (HSNE) cultures were subjected to transepithelial ion transport measurements using pharmacologic manipulation in Ussing chambers. CBF activation was also monitored. Murine nasal potential difference (NPD) was measured in vivo. Results Ussing chamber tracings revealed ethanol activated CFTR-mediated Cl transport in a dose-dependent fashion in WT MNSE (n=4, p<0.05) and HSNE (n=4, p<0.05). Ethanol also significantly increased CBF (fold-change) in WT MNSE cultures in a dose dependent fashion [PBS, 1.33+/−0.04; 0.25% Ethanol, 1.37+/−0.09; 0.5% Ethanol, 1.53+/−0.06 (p<0.05), 1% Ethanol, 1.62+/−0.1 (p<0.05)]. Lack of stimulation in CFTR−/− and F508del/F508del cultures indicated activity was dependent on the presence of intact functional CFTR. Ethanol perfusion (0.5%) resulted in a significant −3.5mV mean NPD polarization when compared to control solution (p<0.05). Conclusion The observation that brief exposure of ethanol stimulated Cl− secretion via CFTR-mediated pathways indicates possible use as topical aerosol delivered alone or in combination with other CFTR activators for diseases of dysfunctional MCC in CRS. PMID:26869199

  18. Selective Non-nucleoside Inhibitors of Human DNA Methyltransferases Active in Cancer Including in Cancer Stem Cells

    PubMed Central

    2015-01-01

    DNA methyltransferases (DNMTs) are important enzymes involved in epigenetic control of gene expression and represent valuable targets in cancer chemotherapy. A number of nucleoside DNMT inhibitors (DNMTi) have been studied in cancer, including in cancer stem cells, and two of them (azacytidine and decitabine) have been approved for treatment of myelodysplastic syndromes. However, only a few non-nucleoside DNMTi have been identified so far, and even fewer have been validated in cancer. Through a process of hit-to-lead optimization, we report here the discovery of compound 5 as a potent non-nucleoside DNMTi that is also selective toward other AdoMet-dependent protein methyltransferases. Compound 5 was potent at single-digit micromolar concentrations against a panel of cancer cells and was less toxic in peripheral blood mononuclear cells than two other compounds tested. In mouse medulloblastoma stem cells, 5 inhibited cell growth, whereas related compound 2 showed high cell differentiation. To the best of our knowledge, 2 and 5 are the first non-nucleoside DNMTi tested in a cancer stem cell line. PMID:24387159

  19. A Ta/W mixed addenda heteropolyacid with excellent acid catalytic activity and proton-conducting property

    NASA Astrophysics Data System (ADS)

    Li, Shujun; Peng, Qingpo; Chen, Xuenian; Wang, Ruoya; Zhai, Jianxin; Hu, Weihua; Ma, Fengji; Zhang, Jie; Liu, Shuxia

    2016-11-01

    A new HPAs H20[P8W60Ta12(H2O)4(OH)8O236]·125H2O (H-1) which comprises a Ta/W mixed addenda heteropolyanion, 20 protons, and 125 crystalline water molecules has been prepared through ion-exchange method. The structure and properties of H-1 have been explored in detail. AC impedance measurements indicate that H-1 is a good solid state proton conducting material at room temperature with a conductivity value of 7.2×10-3 S cm-1 (25 °C, 30% RH). Cyclic voltammograms of H-1 indicate the electrocatalytic activity towards the reduction of nitrite. Hammett acidity constant H0 of H-1 in CH3CN is -2.91, which is the strongest among the present known HPAs. Relatively, H-1 exhibits excellent catalytic activities toward acetal reaction.

  20. Novel stilbenoids, including cannabispiradienone glycosides, from Tragopogon tommasinii (Asteraceae, Cichorieae) and their potential anti-inflammatory activity.

    PubMed

    Granica, Sebastian; Piwowarski, Jakub P; Randazzo, Antonio; Schneider, Peter; Żyżyńska-Granica, Barbara; Zidorn, Christian

    2015-09-01

    A phytochemical investigation of Tragopogon tommasinii Sch.Bip. (Asteraceae, Cichorieae) yielded a total of 21 natural products, two simple phenolic acids (4-hydroxybenzoic acid and p-coumaric acid), four caffeic acid derivatives (chlorogenic acid, 3-O-caffeoylquinic acid, 3,5-O-dicaffeoylquinic acid, and 4,5-O-dicaffeoylquinic acid), six flavonoids (luteolin, luteolin 7-O-glucoside, vitexin, orientin, quercetin 3-O-glucoside, and isorhamnetin 3-O-glucoside), three simple bibenzyls [2-carboxyl-5-hydroxy-3-methoxy-4'-β-glucopyranosyl-oxybibenzyl, 3-caffeoyl-(9→5)-β-apiosyl-(1→6)-β-glucopyranosyloxy-5,4'-dihydroxy-3'-methoxybibenzyl, 3-caffeoyl-(9→5)-β-apiosyl-(1→6)-β-glucopyranosyloxy-4'-dihydroxy-5,3'-dimethoxybibenzyl], three phtalides [3-(4-β-glucopyranosyloxybenzyl)-7-hydroxy-5-methoxyphtalide, 7-β-glucopyranosyloxy-(S)-3-(4-hydroxybenzyl)-5-methoxyphtalide, and 7-(1→6)-α-rhamnosyl-β-glucopyranosyloxy-(S)-3-(4-hydroxybenzyl)-5-methoxyphtalide], two cannabispiradienone derivatives [3-O-β-glucopyranosyldemethoxycannabispiradienone and 3-caffeoyl-(9→5)-β-apiosyl-(1→6)-β-glucopyranosyloxydemethoxycannabispiradienone], and tetra-N-coumaroyl spermine. The three bibenzyls, the latter two benzylphthalides, and both cannabispiradienone derivatives represent new natural compounds and all compounds, except the caffeic acid derivatives and the flavonoids were new for T. tommasinii. The structures were established by HR mass spectrometry, extensive 1D and 2D NMR spectroscopy, and CD spectroscopy. Moreover, the potential anti-inflammatory activities of the new compounds were assayed using human neutrophils and their production of IL-1b, IL-8, TNF-α and MMP-9 as well as the expression of TLR-4, respectively.

  1. Field-assisted synthesis of SERS-active silver nanoparticles using conducting polymers

    NASA Astrophysics Data System (ADS)

    Xu, Ping; Jeon, Sea-Ho; Mack, Nathan H.; Doorn, Stephen K.; Williams, Darrick J.; Han, Xijiang; Wang, Hsing-Lin

    2010-08-01

    A gradient of novel silver nanostructures with widely varying sizes and morphologies is fabricated on a single conducting polyaniline-graphite (P-G) membrane with the assistance of an external electric field. It is believed that the formation of such a silver gradient is a synergetic consequence of the generation of a silver ion concentration gradient along with an electrokinetic flow of silver ions in the field-assisted model, which greatly influences the nucleation and growth mechanism of Ag particles on the P-G membrane. The produced silver dendrites, flowers and microspheres, with sharp edges, intersections and bifurcations, all present strong surface enhanced Raman spectroscopy (SERS) responses toward an organic target molecule, mercaptobenzoic acid (MBA). This facile field-assisted synthesis of Ag nanoparticles via chemical reduction presents an alternative approach to nanomaterial fabrication, which can yield a wide range of unique structures with enhanced optical properties that were previously inaccessible by other synthetic routes.A gradient of novel silver nanostructures with widely varying sizes and morphologies is fabricated on a single conducting polyaniline-graphite (P-G) membrane with the assistance of an external electric field. It is believed that the formation of such a silver gradient is a synergetic consequence of the generation of a silver ion concentration gradient along with an electrokinetic flow of silver ions in the field-assisted model, which greatly influences the nucleation and growth mechanism of Ag particles on the P-G membrane. The produced silver dendrites, flowers and microspheres, with sharp edges, intersections and bifurcations, all present strong surface enhanced Raman spectroscopy (SERS) responses toward an organic target molecule, mercaptobenzoic acid (MBA). This facile field-assisted synthesis of Ag nanoparticles via chemical reduction presents an alternative approach to nanomaterial fabrication, which can yield a wide range

  2. The activation effect of hainantoxin-I, a peptide toxin from the Chinese spider, Ornithoctonus hainana, on intermediate-conductance Ca2+-activated K+ channels.

    PubMed

    Huang, Pengfei; Zhang, Yiya; Chen, Xinyi; Zhu, Li; Yin, Dazhong; Zeng, Xiongzhi; Liang, Songping

    2014-08-21

    Intermediate-conductance Ca2+-activated K+ (IK) channels are calcium/calmodulin-regulated voltage-independent K+ channels. Activation of IK currents is important in vessel and respiratory tissues, rendering the channels potential drug targets. A variety of small organic molecules have been synthesized and found to be potent activators of IK channels. However, the poor selectivity of these molecules limits their therapeutic value. Venom-derived peptides usually block their targets with high specificity. Therefore, we searched for novel peptide activators of IK channels by testing a series of toxins from spiders. Using electrophysiological experiments, we identified hainantoxin-I (HNTX-I) as an IK-channel activator. HNTX-I has little effect on voltage-gated Na+ and Ca2+ channels from rat dorsal root ganglion neurons and on the heterologous expression of voltage-gated rapidly activating delayed rectifier K+ channels (human ether-à-go-go-related gene; human ERG) in HEK293T cells. Only 35.2% ± 0.4% of the currents were activated in SK channels, and there was no effect on BK channels. We demonstrated that HNTX-I was not a phrenic nerve conduction blocker or acutely toxic. This is believed to be the first report of a peptide activator effect on IK channels. Our study suggests that the activity and selectivity of HNTX-I on IK channels make HNTX-I a promising template for designing new drugs for cardiovascular diseases.

  3. Epigenetic upregulation of large-conductance Ca2+-activated K+ channel expression in uterine vascular adaptation to pregnancy.

    PubMed

    Chen, Man; Dasgupta, Chiranjib; Xiong, Fuxia; Zhang, Lubo

    2014-09-01

    Our previous study demonstrated that pregnancy increased large-conductance Ca(2+)-activated potassium channel β1 subunit (BKβ1) expression and large-conductance Ca(2+)-activated potassium channel activity in uterine arteries, which were abrogated by chronic hypoxia. The present study tested the hypothesis that promoter methylation/demethylation is a key mechanism in epigenetic reprogramming of BKβ1 expression patterns in uterine arteries. Ovine BKβ1 promoter of 2315 bp spanning from -2211 to +104 of the transcription start site was cloned, and an Sp1-380 binding site that contains CpG dinucleotide in its core binding sequences was identified. Site-directed deletion of the Sp1 site significantly decreased the BKβ1 promoter activity. Estrogen receptor-α bound to the Sp1 site through tethering to Sp1 and upregulated the expression of BKβ1. The Sp1 binding site at BKβ1 promoter was highly methylated in uterine arteries of nonpregnant sheep, and methylation inhibited transcription factor binding and BKβ1 promoter activity. Pregnancy caused a significant decrease in CpG methylation at the Sp1 binding site and increased Sp1 binding to the BKβ1 promoter and BKβ1 mRNA abundance. Chronic hypoxia during gestation abrogated this pregnancy-induced demethylation and upregulation of BKβ1 expression. The results provide evidence of a novel mechanism of promoter demethylation in pregnancy-induced reprogramming of large-conductance Ca(2+)-activated potassium channel expression and function in uterine arteries and suggest new insights of epigenetic mechanisms linking gestational hypoxia to aberrant uteroplacental circulation and increased risk of preeclampsia.

  4. Electro-active Polymer Actuator Based on Sulfonated Polyimide with Highly Conductive Silver Electrodes Via Self-metallization.

    PubMed

    Song, Jiangxuan; Jeon, Jin-Han; Oh, Il-Kwon; Park, K C

    2011-10-01

    We report here a facile synthesis of high performance electro-active polymer actuator based on a sulfonated polyimide with well-defined silver electrodes via self-metallization. The proposed method greatly reduces fabrication time and cost, and obviates a cation exchange process required in the fabrication of ionic polymer-metal composite actuators. Also, the self-metallized silver electrodes exhibit outstanding metal-polymer adhesion with high conductivity, resulting in substantially larger tip displacements compared with Nafion-based actuators.

  5. Bactericidal activity, eggshell conductance, and hatchability effects of ozone versus formaldehyde disinfection

    SciTech Connect

    Whistler, P.E.; Sheldon, B.W. )

    1989-08-01

    Ozone and formaldehyde were evaluated as disinfectants in a prototype laboratory setter against microorganisms that are naturally present on fertile, freshly laid, broiler hatching eggs. Significantly lower microbial counts of over 2.5 log10 (P less than .05) were observed for water-misted and ozonated (2.83% by weight) eggs or formaldehyde-fumigated (triple strength) eggs than for control and water-misted eggs. Eggshell conductance studies as measured by egg moisture losses in a desiccator showed no significant differences (P greater than .05) among untreated, water misted, ozonated (3.06% by weight) with water mist, or formaldehyde (triple strength)-fumigated eggs. Hatchability was significantly reduced (26.5 to 37.5%) following ozonation (3.03% ozone by weight, 2 h) in comparison with effects of no treatment or water misting. Misting with ozonation was equally as effective as formaldehyde fumigation in reducing microbial counts. However, ozone treatment at the concentrations tested significantly reduced hatchability when compared with results of either no treatment, water misting, or an average hatchability figure for formaldehyde fumigation. These findings indicate that ozone is a good disinfectant yet may adversely affect embryo development when given in the gaseous form.

  6. Delineation of the clotrimazole/TRAM-34 binding site on the intermediate conductance calcium-activated potassium channel, IKCa1.

    PubMed

    Wulff, H; Gutman, G A; Cahalan, M D; Chandy, K G

    2001-08-24

    Selective and potent triarylmethane blockers of the intermediate conductance calcium-activated potassium channel, IKCa1, have therapeutic use in sickle cell disease and secretory diarrhea and as immunosuppressants. Clotrimazole, a membrane-permeant triarylmethane, blocked IKCa1 with equal affinity when applied externally or internally, whereas a membrane-impermeant derivative TRAM-30 blocked the channel only when applied to the cytoplasmic side, indicating an internal drug-binding site. Introduction of the S5-P-S6 region of the triarylmethane-insensitive small conductance calcium-activated potassium channel SKCa3 into IKCa1 rendered the channel resistant to triarylmethanes. Replacement of Thr(250) or Val(275) in IKCa1 with the corresponding SKCa3 residues selectively abolished triarylmethane sensitivity without affecting the affinity of the channel for tetraethylammonium, charybdotoxin, and nifedipine. Introduction of these two residues into SKCa3 rendered the channel sensitive to triarylmethanes. In a molecular model of IKCa1, Thr(250) and Val(275) line a water-filled cavity just below the selectivity filter. Structure-activity studies suggest that the side chain methyl groups of Thr(250) and Val(275) may lock the triarylmethanes in place via hydrophobic interactions with the pi-electron clouds of the phenyl rings. The heterocyclic moiety may project into the selectivity filter and obstruct the ion-conducting pathway from the inside.

  7. Are Physical Activity and Academic Performance Compatible? Academic Achievement, Conduct, Physical Activity and Self-Esteem of Hong Kong Chinese Primary School Children

    ERIC Educational Resources Information Center

    Yu, C. C. W.; Chan, Scarlet; Cheng, Frances; Sung, R. Y. T.; Hau, Kit-Tai

    2006-01-01

    Education is so strongly emphasized in the Chinese culture that academic success is widely regarded as the only indicator of success, while too much physical activity is often discouraged because it drains energy and affects academic concentration. This study investigated the relations among academic achievement, self-esteem, school conduct and…

  8. Glutamate and GABA activate different receptors and Cl(-) conductances in crab peptide-secretory neurons.

    PubMed

    Duan, S; Cooke, I M

    2000-01-01

    Responses to rapid application of glutamic acid (Glu) and gamma-aminobutyric acid (GABA), 0.01-3 mM, were recorded by whole-cell patch clamp of cultured crab (Cardisoma carnifex) X-organ neurons. Responses peaked within 200 ms. Both Glu and GABA currents had reversal potentials that followed the Nernst Cl(-) potential when [Cl(-)](i) was varied. A Boltzmann fit to the normalized, averaged dose-response curve for Glu indicated an EC(50) of 0.15 mM and a Hill coefficient of 1.05. Rapid (t(1/2) approximately 1 s) desensitization occurred during Glu but not GABA application that required >2 min for recovery. Desensitization was unaffected by concanavalin A or cyclothiazide. N-methyl-D-aspartate, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, quisqualate, and kainate (to 1 mM) were ineffective, nor were Glu responses influenced by glycine (1 microM) or Mg(2+) (0-26 mM). Glu effects were imitated by ibotenic acid (0.1 mM). The following support the conclusion that Glu and GABA act on different receptors: 1) responses sum; 2) desensitization to Glu or ibotenic acid did not diminish GABA responses; 3) the Cl(-)-channel blockers picrotoxin and niflumic acid (0.5 mM) inhibited Glu responses by approximately 90 and 80% but GABA responses by approximately 50 and 20%; and 4) polyvinylpyrrolydone-25 (2 mM in normal crab saline) eliminated Glu responses but left GABA responses unaltered. Thus crab secretory neurons have separate receptors responsive to Glu and to GABA, both probably ionotropic, and mediating Cl(-) conductance increases. In its responses and pharmacology, this crustacean Glu receptor resembles Cl(-)-permeable Glu receptors previously described in invertebrates and differs from cation-permeable Glu receptors of vertebrates and invertebrates.

  9. Chronic hypoxia suppresses pregnancy-induced upregulation of large-conductance Ca2+-activated K+ channel activity in uterine arteries.

    PubMed

    Hu, Xiang-Qun; Xiao, Daliao; Zhu, Ronghui; Huang, Xiaohui; Yang, Shumei; Wilson, Sean M; Zhang, Lubo

    2012-07-01

    Our previous study demonstrated that increased Ca(2+)-activated K(+) (BK(Ca)) channel activity played a key role in the normal adaptation of reduced myogenic tone of uterine arteries in pregnancy. The present study tested the hypothesis that chronic hypoxia during gestation inhibits pregnancy-induced upregulation of BK(Ca) channel function in uterine arteries. Resistance-sized uterine arteries were isolated from nonpregnant and near-term pregnant sheep maintained at sea level (≈ 300 m) or exposed to high-altitude (3801 m) hypoxia for 110 days. Hypoxia during gestation significantly inhibited pregnancy-induced upregulation of BK(Ca) channel activity and suppressed BK(Ca) channel current density in pregnant uterine arteries. This was mediated by a selective downregulation of BK(Ca) channel β1 subunit in the uterine arteries. In accordance, hypoxia abrogated the role of the BK(Ca) channel in regulating pressure-induced myogenic tone of uterine arteries that was significantly elevated in pregnant animals acclimatized to chronic hypoxia. In addition, hypoxia abolished the steroid hormone-mediated increase in the β1 subunit and BK(Ca) channel current density observed in nonpregnant uterine arteries. Although the activation of protein kinase C inhibited BK(Ca) channel current density in pregnant uterine arteries of normoxic sheep, this effect was ablated in the hypoxic animals. The results demonstrate that selectively targeting BK(Ca) channel β1 subunit plays a critical role in the maladaption of uteroplacental circulation caused by chronic hypoxia, which contributes to the increased incidence of preeclampsia and fetal intrauterine growth restriction associated with gestational hypoxia. PMID:22665123

  10. Medical relief activities conducted by Nippon Medical School in the acute phase of the Great East Japan Earthquake 2011.

    PubMed

    Fuse, Akira; Shuto, Yuki; Ando, Fumihiko; Shibata, Masafumi; Watanabe, Akihiro; Onda, Hidetaka; Masuno, Tomohiko; Yokota, Hiroyuki

    2011-01-01

    At 14:46 on March 11, 2011, the Great East Japan Earthquake and tsunami occurred off the coast of Honshu, Japan. In the acute phase of this catastrophe, one of our teams was deployed as a Tokyo Disaster Medical Assistance Team (DMAT) to Kudan Kaikan in Tokyo, where the ceiling of a large hall had partially collapsed as the result of the earthquake, to conduct triage at the scene: 6 casualties were assigned to the red category (immediate), which included 1 case of cardiopulmonary arrest and 1 of flail chest; 8 casualties in the yellow category (delayed); and 22 casualties in the green category (minor). One severely injured person was transported to our hospital. Separately, our medical team was deployed to Miyagi 2 hours after the earthquake in our multipurpose medical vehicle as part of Japan DMAT (J-DMAT). We were the first DMAT from the metropolitan area to arrive, but we were unable to start medical relief activities because the information infrastructure had been destroyed and no specific information had yet reached the local headquarters. Early next morning, J-DMAT decided to support Sendai Medical Center and search and rescue efforts in the affected area and to establish a staging care unit at Camp Kasuminome of the Japan Self-Defense Force. Our team joined others to establish the staging care unit. Because information was still confused until day 3 of the disaster and we could not adequately grasp onsite medical needs, our J-DMAT decided to provide onsite support at Ishinomaki Red Cross Hospital, a disaster base hospital, and relay information about its needs to the local J-DMAT headquarters. Although our medical relief teams were deployed as quickly as possible, we could not begin medical relief activities immediately owing to the severely damaged information infrastructure. Only satellite mobile phones could be operated, and information on the number of casualties and the severity of shortages of lifeline services could be obtained only through a "go and

  11. Medical relief activities conducted by Nippon Medical School in the acute phase of the Great East Japan Earthquake 2011.

    PubMed

    Fuse, Akira; Shuto, Yuki; Ando, Fumihiko; Shibata, Masafumi; Watanabe, Akihiro; Onda, Hidetaka; Masuno, Tomohiko; Yokota, Hiroyuki

    2011-01-01

    At 14:46 on March 11, 2011, the Great East Japan Earthquake and tsunami occurred off the coast of Honshu, Japan. In the acute phase of this catastrophe, one of our teams was deployed as a Tokyo Disaster Medical Assistance Team (DMAT) to Kudan Kaikan in Tokyo, where the ceiling of a large hall had partially collapsed as the result of the earthquake, to conduct triage at the scene: 6 casualties were assigned to the red category (immediate), which included 1 case of cardiopulmonary arrest and 1 of flail chest; 8 casualties in the yellow category (delayed); and 22 casualties in the green category (minor). One severely injured person was transported to our hospital. Separately, our medical team was deployed to Miyagi 2 hours after the earthquake in our multipurpose medical vehicle as part of Japan DMAT (J-DMAT). We were the first DMAT from the metropolitan area to arrive, but we were unable to start medical relief activities because the information infrastructure had been destroyed and no specific information had yet reached the local headquarters. Early next morning, J-DMAT decided to support Sendai Medical Center and search and rescue efforts in the affected area and to establish a staging care unit at Camp Kasuminome of the Japan Self-Defense Force. Our team joined others to establish the staging care unit. Because information was still confused until day 3 of the disaster and we could not adequately grasp onsite medical needs, our J-DMAT decided to provide onsite support at Ishinomaki Red Cross Hospital, a disaster base hospital, and relay information about its needs to the local J-DMAT headquarters. Although our medical relief teams were deployed as quickly as possible, we could not begin medical relief activities immediately owing to the severely damaged information infrastructure. Only satellite mobile phones could be operated, and information on the number of casualties and the severity of shortages of lifeline services could be obtained only through a "go and

  12. High water-stressed population estimated by world water resources assessment including human activities under SRES scenarios

    NASA Astrophysics Data System (ADS)

    Kiguchi, M.; Shen, Y.; Kanae, S.; Oki, T.

    2009-04-01

    In an argument of the reduction and the adaptation for the climate change, the evaluation of the influence by the climate change is important. When we argue in adaptation plan from a damage scale and balance with the cost, it is particularly important. Parry et al (2001) evaluated the risks in shortage of water, malaria, food, the risk of the coast flood by temperature function and clarified the level of critical climate change. According to their evaluation, the population to be affected by the shortage of water suddenly increases in the range where temperature increases from 1.5 to 2.0 degree in 2080s. They showed how much we need to reduce emissions in order to draw-down significantly the number at risk. This evaluation of critical climate change threats and targets of water shortage did not include the water withdrawal divided by water availability. Shen et al (2008a) estimated the water withdrawal of projection of future world water resources according to socio-economic driving factors predicted for scenarios A1b, A2, B1, and B2 of the Special Report on Emission Scenarios (SRES). However, these results were in function of not temperature but time. The assessment of the highly water-stressed population considered the socioeconomic development is necessary for a function of the temperature. Because of it is easy to understand to need to reduce emission. We present a multi-GCM analysis of the global and regional populations lived in highly water-stressed basin for a function of the temperature using the socioeconomic data and the outputs of GCMs. In scenario A2, the population increases gradually with warming. On the other hand, the future projection population in scenario A1b and B1 increase gradually until the temperature anomaly exceeds around from +1 to +1.5 degree. After that the population is almost constant. From Shen et al (2008b), we evaluated the HWSP and its ratio in the world with temperature function for scenarios A1B, A2, and B1 by the index of W

  13. Overcoming the challenges of conducting physical activity and built environment research in Latin America: IPEN Latin America

    PubMed Central

    Salvo, Deborah; Reis, Rodrigo S.; Sarmiento, Olga L.; Pratt, Michael

    2014-01-01

    Objective There is evidence linking the built environment (BE) with physical activity (PA), but few studies have been conducted in Latin America (LA). State-of-the-art methods and protocols have been designed in and applied in high-income countries (HIC). In this paper we identify key challenges and potential solutions to conducting high quality PA and BE research in LA. Methods The experience of implementing the IPEN data collection protocol (IPEN: International Physical Activity Environment Network) in Curitiba, Brazil; Bogotá, Colombia; and Cuernavaca, Mexico (2010-2011); is described to identify challenges for conducting PA and BE research in LA. Results Five challenges were identified: Lack of academic capacity (implemented solutions (IS): building a strong international collaborative network); limited data availability, access and quality (IS: partnering with influential local institutions, and crafting creative solutions to use the best-available data); socio-political, socio-cultural and socio-economic context (IS: in-person recruitment and data collection, alternative incentives); safety (IS: strict rules for data collection procedures, and specific measures to increase trust); appropriateness of instruments and measures (IS: survey adaptation, use of standardized additional survey components, and employing a context-based approach to understanding the relationship between PA and the BE). Advantages of conducting PA and BE research in LA were also identified. Conclusions Conducting high quality PA and BE research in LA is challenging but feasible. Networks of institutions and researchers from both HIC and LMIC play a key role. The lessons learnt from the IPEN LA study may be applicable to other LMIC. PMID:25456800

  14. Act as NARSTO Management Coordinator and Conduct Research In Support of NARSTO Activities

    SciTech Connect

    Pennell, William T.

    2014-01-22

    This grant funded the position of NARSTO Management Coordinator. NARSTO was a public-private partnership with members from government, utilities, industry, and academe in Canada, the United States and Mexico. NARSTO planed and coordinated independently sponsored projects and tasks designed to identify and resolve policy-relevant science questions related to a) Anthropogenic and biogenic air-pollution sources and emissions, b) The complex physical and chemical processes affecting the accumulation of pollutants in the troposphere (including greenhouse gases and aerosols), c) The potential of certain pollutants to react and generate oxidants and fine particles in the troposphere, d) The development, intercomparison, and application of atmospheric models, e) The development of monitoring studies and methodologies needed to assess emission control effectiveness for selected greenhouse gases and aerosols, air pollutants and their precursors, and f) The attainment of the national air-quality and climate-stabilization goals and standards established by each member Nation

  15. Integrating high electrical conductivity and photocatalytic activity in cotton fabric by cationizing for enriched coating of negatively charged graphene oxide.

    PubMed

    Sahito, Iftikhar Ali; Sun, Kyung Chul; Arbab, Alvira Ayoub; Qadir, Muhammad Bilal; Jeong, Sung Hoon

    2015-10-01

    Electroconductive textiles have attended tremendous focus recently and researchers are making efforts to increase conductivity of e-textiles, in order to increase the use of such flexible and low cost textile materials. In this study, surface conductivity and photo catalytic activity of standard cotton fabric (SCF) was enhanced by modifying its surface charge, from negative to positive, using Bovine Serum Albumin (BSA) as a cationic agent, to convert it into cationised cotton fabric (CCF). Then, both types of fabrics were dip coated with a simple dip and dry technique for the adsorption of negatively charged graphene oxide (GO) sheets onto its surface. This resulted in 67.74% higher loading amount of GO on the CCF making self-assembly. Finally, this coating was chemically converted by vapor reduction using hydrazine hydrate to reduced graphene oxide (rGO) for restoration of a high electrical conductivity at the fabric surface. Our results revealed that with such high loading of GO, the surface resistance of CCF was only 40Ω/sq as compared to 510Ω/sq of the SCF and a 66% higher photo catalytic activity was also achieved through cationization for improved GO coating. Graphene coated SCF and CCF were characterized using FE-SEM, FTIR, Raman, UV-vis, WAXD, EDX and XPS spectroscopy to ascertain successful reduction of GO to rGO. The effect of BSA treatment on adsorption of cotton fabric was studied using drop shape analyzer to measure contact angle and for thermal and mechanical resistance, the fabric was tested for TGA and tensile strength, respectively. rGO coated fabric also showed slightly improved thermal stability yet a minor loss of strength was observed. The high flexibility, photocatalytic activity and excellent conductivity of this fabric suggests that it can be used as an electrode material for various applications. PMID:26076630

  16. Integrating high electrical conductivity and photocatalytic activity in cotton fabric by cationizing for enriched coating of negatively charged graphene oxide.

    PubMed

    Sahito, Iftikhar Ali; Sun, Kyung Chul; Arbab, Alvira Ayoub; Qadir, Muhammad Bilal; Jeong, Sung Hoon

    2015-10-01

    Electroconductive textiles have attended tremendous focus recently and researchers are making efforts to increase conductivity of e-textiles, in order to increase the use of such flexible and low cost textile materials. In this study, surface conductivity and photo catalytic activity of standard cotton fabric (SCF) was enhanced by modifying its surface charge, from negative to positive, using Bovine Serum Albumin (BSA) as a cationic agent, to convert it into cationised cotton fabric (CCF). Then, both types of fabrics were dip coated with a simple dip and dry technique for the adsorption of negatively charged graphene oxide (GO) sheets onto its surface. This resulted in 67.74% higher loading amount of GO on the CCF making self-assembly. Finally, this coating was chemically converted by vapor reduction using hydrazine hydrate to reduced graphene oxide (rGO) for restoration of a high electrical conductivity at the fabric surface. Our results revealed that with such high loading of GO, the surface resistance of CCF was only 40Ω/sq as compared to 510Ω/sq of the SCF and a 66% higher photo catalytic activity was also achieved through cationization for improved GO coating. Graphene coated SCF and CCF were characterized using FE-SEM, FTIR, Raman, UV-vis, WAXD, EDX and XPS spectroscopy to ascertain successful reduction of GO to rGO. The effect of BSA treatment on adsorption of cotton fabric was studied using drop shape analyzer to measure contact angle and for thermal and mechanical resistance, the fabric was tested for TGA and tensile strength, respectively. rGO coated fabric also showed slightly improved thermal stability yet a minor loss of strength was observed. The high flexibility, photocatalytic activity and excellent conductivity of this fabric suggests that it can be used as an electrode material for various applications.

  17. Swelling-activated chloride and potassium conductance in primary cultures of mouse proximal tubules. Implication of KCNE1 protein.

    PubMed

    Barrière, H; Rubera, I; Belfodil, R; Tauc, M; Tonnerieux, N; Poujeol, C; Barhanin, J; Poujeol, P

    2003-06-01

    Volume-sensitive chloride and potassium currents were studied, using the whole-cell clamp technique, in cultured wild-type mouse proximal convoluted tubule (PCT) epithelial cells and compared with those measured in PCT cells from null mutant kcne1 -/- mice. In wild-type PCT cells in primary culture, a Cl- conductance activated by cell swelling was identified. The initial current exhibited an outwardly rectifying current-voltage (I-V) relationship, whereas steady-state current showed decay at depolarized membrane potentials. The ion selectivity was I- > Br- > Cl- > > gluconate. This conductance was sensitive to 1 mM 4,4'-Diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), 0.1 mM 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB) and 1 mM diphenylamine-2-carboxylate (DPC). Osmotic stress also activated K+ currents. These currents are time-independent, activated at depolarized potentials, and inhibited by 0.5 mM quinidine, 5 mM barium, and 10 microM clofilium but are insensitive to 1 mM tetraethylammonium (TEA), 10 nM charybdotoxin (CTX), and 10 microM 293B. In contrast, the null mutation of kcne1 completely impaired volume-sensitive chloride and potassium currents in PCT. The transitory transfection of kcne1 restores both Cl- and K+ swelling-activated currents, confirming the implication of KCNE1 protein in the cell-volume regulation in PCT cells in primary cultures. PMID:12962276

  18. Electrospun conducting polymer nanofibers as the active material in sensors and diodes

    NASA Astrophysics Data System (ADS)

    Pinto, Nicholas J.

    2013-03-01

    Polyaniline doped with camphorsulfonic acid (PANi-HCSA) and poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonic acid (PEDOT-PSSA) were electrospun separately to obtain individual nanofibers which were captured on Si/SiO2 substrates and electrically characterized. The fiber resistance was recorded as a function of time in the presence of vapours of aliphatic alcohols of varying sizes. Due to the large surface to volume ratio, uniform diameter and small quantity of active material used in the construction, these sensor responses are very quick. Sensors made from individual fibers also show true saturation upon exposure to and removal of the sensing gas. A Schottky diode was also fabricated using an n-doped Si/SiO2 substrate and a single PANi-HCSA fiber and tested in vacuum and in ammonia gas. The diode response was instantaneous upon exposure to ammonia with nearly complete recovery of the current upon pumping out the ammonia, thereby making it a reusable sensor with rectifying behaviour i.e. multifunctional.

  19. Distribution of High-Conductance Calcium-Activated Potassium Channels in Rat Vestibular Epithelia

    PubMed Central

    Schweizer, Felix E.; Savin, David; Luu, Cindy; Sultemeier, David R.; Hoffman, Larry F.

    2011-01-01

    Voltage- and calcium-activated potassium channels (BK) are important regulators of neuronal excitability. BK channels seem to be crucial for frequency tuning in nonmammalian vestibular and auditory hair cells. However, there are a paucity of data concerning BK expression in mammalian vestibular hair cells. We therefore investigated the localization of BK channels in mammalian vestibular hair cells, specifically in rat vestibular neuroepithelia. We find that only a subset of hair cells in the utricle and the crista ampullaris express BK channels. BK-positive hair cells are located mainly in the medial striolar region of the utricle, where they constitute at most 12% of hair cells, and in the central zone of the horizontal crista. A majority of BK-positive hair cells are encapsulated by a calretinin-positive calyx defining them as type I cells. The remainder are either type I cells encapsulated by a calretinin-negative calyx or type II hair cells. Surprisingly, the number of BK-positive hair cells in the utricle peaks in juvenile rats and declines in early adulthood. BK channels were not found in vestibular afferent dendrites or somata. Our data indicate that BK channel expression in the mammalian vestibular system differs from the expression pattern in the mammalian auditory and the nonmammalian vestibular system. The molecular diversity of vestibular hair cells indicates a functional diversity that has not yet been fully characterized. The predominance of BK-positive hair cells within the medial striola of juvenile animals suggests that they contribute to a scheme of highly lateralized coding of linear head movements during late development. PMID:19731297

  20. Apparent intermediate K conductance channel hyposmotic activation in human lens epithelial cells.

    PubMed

    Lauf, Peter K; Misri, Sandeep; Chimote, Ameet A; Adragna, Norma C

    2008-03-01

    This study explores the nature of K fluxes in human lens epithelial cells (LECs) in hyposmotic solutions. Total ion fluxes, Na-K pump, Cl-dependent Na-K-2Cl (NKCC), K-Cl (KCC) cotransport, and K channels were determined by 85Rb uptake and cell K (Kc) by atomic absorption spectrophotometry, and cell water gravimetrically after exposure to ouabain +/- bumetanide (Na-K pump and NKCC inhibitors), and ion channel inhibitors in varying osmolalities with Na, K, or methyl-d-glucamine and Cl, sulfamate, or nitrate. Reverse transcriptase polymerase chain reaction (RT-PCR), Western blot analyses, and immunochemistry were also performed. In isosmotic (300 mosM) media approximately 90% of the total Rb influx occurred through the Na-K pump and NKCC and approximately 10% through KCC and a residual leak. Hyposmotic media (150 mosM) decreased K(c) by a 16-fold higher K permeability and cell water, but failed to inactivate NKCC and activate KCC. Sucrose replacement or extracellular K to >57 mM, but not Rb or Cs, in hyposmotic media prevented Kc and water loss. Rb influx equaled Kc loss, both blocked by clotrimazole (IC50 approximately 25 microM) and partially by 1-[(2-chlorophenyl) diphenylmethyl]-1H-pyrazole (TRAM-34) inhibitors of the IK channel KCa3.1 but not by other K channel or connexin hemichannel blockers. Of several anion channel blockers (dihydro-indenyl)oxy]alkanoic acid (DIOA), 4-2(butyl-6,7-dichloro-2-cyclopentylindan-1-on-5-yl)oxybutyric acid (DCPIB), and phloretin totally or partially inhibited Kc loss and Rb influx, respectively. RT-PCR and immunochemistry confirmed the presence of KCa3.1 channels, aside of the KCC1, KCC2, KCC3 and KCC4 isoforms. Apparently, IK channels, possibly in parallel with volume-sensitive outwardly rectifying Cl channels, effect regulatory volume decrease in LECs. PMID:18184876

  1. Large-conductance Ca²⁺-activated potassium channel in mitochondria of endothelial EA.hy926 cells.

    PubMed

    Bednarczyk, Piotr; Koziel, Agnieszka; Jarmuszkiewicz, Wieslawa; Szewczyk, Adam

    2013-06-01

    In the present study, we describe the existence of a large-conductance Ca²⁺-activated potassium (BKCa) channel in the mitochondria of the human endothelial cell line EA.hy926. A single-channel current was recorded from endothelial mitoplasts (i.e., inner mitochondrial membrane) using the patch-clamp technique in the mitoplast-attached mode. A potassium-selective current was recorded with a mean conductance equal to 270 ± 10 pS in a symmetrical 150/150 mM KCl isotonic solution. The channel activity, which was determined as the open probability, increased with the addition of calcium ions and the potassium channel opener NS1619. Conversely, the activity of the channel was irreversibly blocked by paxilline and iberiotoxin, BKCa channel inhibitors. The open-state probability was found to be voltage dependent. The substances known to modulate BKCa channel activity influenced the bioenergetics of mitochondria isolated from human endothelial EA.hy926 cells. In isolated mitochondria, 100 μM Ca²⁺, 10 μM NS1619, and 0.5 μM NS11021 depolarized the mitochondrial membrane potential and stimulated nonphosphorylating respiration. These effects were blocked by iberiotoxin and paxilline in a potassium-dependent manner. Under phosphorylating conditions, NS1619-induced, iberiotoxin-sensitive uncoupling diverted energy from ATP synthesis during the phosphorylating respiration of the endothelial mitochondria. Immunological analysis with antibodies raised against proteins of the plasma membrane BKCa channel identified a pore-forming α-subunit and an auxiliary β₂-subunit of the channel in the endothelial mitochondrial inner membrane. In conclusion, we show for the first time that the inner mitochondrial membrane in human endothelial EA.hy926 cells contains a large-conductance calcium-dependent potassium channel with properties similar to those of the surface membrane BKCa channel.

  2. Enhanced thermal stability under DC electrical conductivity retention and visible light activity of Ag/TiO₂@polyaniline nanocomposite film.

    PubMed

    Ansari, Mohd Omaish; Khan, Mohammad Mansoob; Ansari, Sajid Ali; Raju, Kati; Lee, Jintae; Cho, Moo Hwan

    2014-06-11

    The development of organic-inorganic photoactive materials has resulted in significant advancements in heterogeneous visible light photocatalysis. This paper reports the synthesis of visible light-active Ag/TiO2@Pani nanocomposite film via a simple biogenic-chemical route. Electrically conducting Ag/TiO2@Pani nanocomposites were prepared by incorporating Ag/TiO2 in N-methyl-2-pyrrolidone solution of polyaniline (Pani), followed by the preparation of Ag/TiO2@Pani nanocomposite film using solution casting technique. The synthesized Ag/TiO2@Pani nanocomposite was confirmed by UV-visible spectroscopy, photoluminescence spectroscopy, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The Ag/TiO2@Pani nanocomposite film showed superior activity towards the photodegradation of methylene blue under visible light compared to Pani film, even after repeated use. Studies on the thermoelectrical behavior by DC electrical conductivity retention under cyclic aging techniques showed that the Ag/TiO2@Pani nanocomposite film possessed a high combination of electrical conductivity and thermal stability. Because of its better thermoelectric performance and photodegradation properties, such materials might be a suitable advancement in the field of smart materials in near future.

  3. A calcium-activated sodium conductance produces a long-duration action potential in the egg of a nemertean worm.

    PubMed Central

    Jaffe, L A; Kado, R T; Kline, D

    1986-01-01

    1. The egg of the nemertean worm Cerebratulus lacteus produced an action potential having a duration of about 9 min. We investigated the ionic conductances which accounted for this long-duration action potential. 2. The peak of the action potential was about +50 mV and depended on extracellular Ca2+, while the plateau potential was about +25 mV and depended on extracellular Na+. 3. Under voltage-clamp conditions, depolarization produced two temporally separate inward currents: a fast current which reached a peak at about 10 ms, and a slow current which took up to 1 min to reach its peak and lasted for several min. 4. The fast current was independent of extracellular Na+, but was blocked by removal of extracellular Ca2+. 5. The slow current was not seen when extracellular Na+ was replaced by choline+ or K+. 6. The slow current did not develop in Ca2+-free sea water, and was reduced to about half if Ca2+ was removed after the current had been initiated. 7. Microinjection of EGTA blocked the slow current, and reduced the action potential duration to about 1 min. 8. We concluded that a voltage-activated Ca2+ conductance produced the peak of the action potential, while a Ca2+-activated Na+ conductance produced its plateau. PMID:2442351

  4. Bournonite PbCuSbS3 : Stereochemically Active Lone-Pair Electrons that Induce Low Thermal Conductivity.

    PubMed

    Dong, Yongkwan; Khabibullin, Artem R; Wei, Kaya; Salvador, James R; Nolas, George S; Woods, Lilia M

    2015-10-26

    An understanding of the structural features and bonding of a particular material, and the properties these features impart on its physical characteristics, is essential in the search for new systems that are of technological interest. For several relevant applications, the design or discovery of low thermal conductivity materials is of great importance. We report on the synthesis, crystal structure, thermal conductivity, and electronic-structure calculations of one such material, PbCuSbS3 . Our analysis is presented in terms of a comparative study with Sb2 S3 , from which PbCuSbS3 can be derived through cation substitution. The measured low thermal conductivity of PbCuSbS3 is explained by the distortive environment of the Pb and Sb atoms from the stereochemically active lone-pair s(2) electrons and their pronounced repulsive interaction. Our investigation suggests a general approach for the design of materials for phase-change-memory, thermal-barrier, thermal-rectification and thermoelectric applications, as well as other functions for which low thermal conductivity is purposefully sought. PMID:26330172

  5. Bournonite PbCuSbS3 : Stereochemically Active Lone-Pair Electrons that Induce Low Thermal Conductivity.

    PubMed

    Dong, Yongkwan; Khabibullin, Artem R; Wei, Kaya; Salvador, James R; Nolas, George S; Woods, Lilia M

    2015-10-26

    An understanding of the structural features and bonding of a particular material, and the properties these features impart on its physical characteristics, is essential in the search for new systems that are of technological interest. For several relevant applications, the design or discovery of low thermal conductivity materials is of great importance. We report on the synthesis, crystal structure, thermal conductivity, and electronic-structure calculations of one such material, PbCuSbS3 . Our analysis is presented in terms of a comparative study with Sb2 S3 , from which PbCuSbS3 can be derived through cation substitution. The measured low thermal conductivity of PbCuSbS3 is explained by the distortive environment of the Pb and Sb atoms from the stereochemically active lone-pair s(2) electrons and their pronounced repulsive interaction. Our investigation suggests a general approach for the design of materials for phase-change-memory, thermal-barrier, thermal-rectification and thermoelectric applications, as well as other functions for which low thermal conductivity is purposefully sought.

  6. Apparent receptor-mediated activation of Ca2+-dependent conductive Cl- transport by shark-derived polyaminosterols.

    PubMed

    Chernova, Marina N; Vandorpe, David H; Clark, Jeffrey S; Williams, Jon I; Zasloff, Michael A; Jiang, Lianwei; Alper, Seth L

    2005-12-01

    The shark liver antimicrobial polyaminosterol squalamine is an angiogenesis inhibitor under clinical investigation as an anti-cancer agent and as a treatment for the choroidal neovascularization associated with macular degeneration of the retina. The related polyaminosterol MSI-1436 is an appetite suppressant that decreases systemic insulin resistance. However, the mechanisms of action of these polyaminosterols are unknown. We report effects of MSI-1436 on Xenopus oocytes consistent with the existence of a receptor for polyaminosterols. MSI-1436 activates bidirectional, trans-chloride-independent Cl- flux in Xenopus oocytes. At least part of this DIDS-sensitive Cl- flux is conductive, as measured using two-electrode voltage-clamp and on-cell patch-clamp techniques. MSI-1436 also elevates cytosolic Ca2+ concentration ([Ca2+]) and increases bidirectional 45Ca2+ flux. Activation of Cl- flux and elevation of cytosolic [Ca2+] by MSI-1436 both are accelerated by lowering bath Ca2+ and are not acutely inhibited by extracellular EGTA. Elevation of cytosolic [Ca2+] by MSI-1436 requires heparin-sensitive intracellular Ca2+ stores. Although injected EGTA abolishes the increased conductive Cl- flux, that Cl- flux is not dependent on heparin-sensitive stores. In low-bath Ca2+ conditions, several structurally related polyaminosterols act as strong agonists or weak agonists of conductive Cl- flux in oocytes. Weak agonist polyaminosterols antagonize the strong agonist, MSI-1436, but upon addition of the conductive Cl- transport inhibitor DIDS, they are converted into strong agonists. Together, these properties operationally define a polyaminosterol receptor at or near the surface of the Xenopus oocyte, provide an initial description of receptor signaling, and suggest routes toward further understanding of a novel class of appetite suppressants and angiogenesis inhibitors. PMID:16109810

  7. Impedance spectroscopic analysis of composite electrode from activated carbon/conductive materials/ruthenium oxide for supercapacitor applications

    SciTech Connect

    Taer, E.; Awitdrus,; Farma, R.; Deraman, M. Talib, I. A.; Ishak, M. M.; Omar, R.; Dolah, B. N. M.; Basri, N. H.; Othman, M. A. R.; Kanwal, S.

    2015-04-16

    Activated carbon powders (ACP) were produced from the KOH treated pre-carbonized rubber wood sawdust. Different conductive materials (graphite, carbon black and carbon nanotubes (CNTs)) were added with a binder (polivinylidene fluoride (PVDF)) into ACP to improve the supercapacitive performance of the activated carbon (AC) electrodes. Symmetric supercapacitor cells, fabricated using these AC electrodes and 1 molar H{sub 2}SO{sub 4} electrolyte, were analyzed using a standard electrochemical impedance spectroscopy technique. The addition of graphite, carbon black and CNTs was found effective in reducing the cell resistance from 165 to 68, 23 and 49 Ohm respectively, and increasing the specific capacitance of the AC electrodes from 3 to 7, 17, 32 F g{sup −1} respectively. Since the addition of CNTs can produce the highest specific capacitance, CNTs were chosen as a conductive material to produce AC composite electrodes that were added with 2.5 %, 5 % and 10 % (by weight) electro-active material namely ruthenium oxide; PVDF binder and CNTs contents were kept at 5 % by weight in each AC composite produced. The highest specific capacitance of the cells obtained in this study was 86 F g{sup −1}, i.e. for the cell with the resistance of 15 Ohm and composite electrode consists of 5 % ruthenium oxide.

  8. Impedance spectroscopic analysis of composite electrode from activated carbon/conductive materials/ruthenium oxide for supercapacitor applications

    NASA Astrophysics Data System (ADS)

    Taer, E.; Deraman, M.; Talib, I. A.; Awitdrus, Farma, R.; Ishak, M. M.; Omar, R.; Dolah, B. N. M.; Basri, N. H.; Othman, M. A. R.; Kanwal, S.

    2015-04-01

    Activated carbon powders (ACP) were produced from the KOH treated pre-carbonized rubber wood sawdust. Different conductive materials (graphite, carbon black and carbon nanotubes (CNTs)) were added with a binder (polivinylidene fluoride (PVDF)) into ACP to improve the supercapacitive performance of the activated carbon (AC) electrodes. Symmetric supercapacitor cells, fabricated using these AC electrodes and 1 molar H2SO4 electrolyte, were analyzed using a standard electrochemical impedance spectroscopy technique. The addition of graphite, carbon black and CNTs was found effective in reducing the cell resistance from 165 to 68, 23 and 49 Ohm respectively, and increasing the specific capacitance of the AC electrodes from 3 to 7, 17, 32 F g-1 respectively. Since the addition of CNTs can produce the highest specific capacitance, CNTs were chosen as a conductive material to produce AC composite electrodes that were added with 2.5 %, 5 % and 10 % (by weight) electro-active material namely ruthenium oxide; PVDF binder and CNTs contents were kept at 5 % by weight in each AC composite produced. The highest specific capacitance of the cells obtained in this study was 86 F g-1, i.e. for the cell with the resistance of 15 Ohm and composite electrode consists of 5 % ruthenium oxide.

  9. Electrochemical activity and high ionic conductivity of lithium copper pyroborate Li6CuB4O10.

    PubMed

    Strauss, Florian; Rousse, Gwenaëlle; Alves Dalla Corte, Daniel; Ben Hassine, Mohamed; Saubanère, Matthieu; Tang, Mingxue; Vezin, Hervé; Courty, Matthieu; Dominko, Robert; Tarascon, Jean-Marie

    2016-06-01

    In the search for new cathode materials for Li-ion batteries, borate (BO3(3-)) based compounds have gained much interest during the last two decades due to the low molecular weight of the borate polyanions which leads to active materials with increased theoretical capacities. In this context we herein report the electrochemical activity versus lithium and the ionic conductivity of a diborate or pyroborate B2O5(4-) based compound, Li6CuB4O10. By combining various electrochemical techniques with in situ X-ray diffraction, we show that this material can reversibly insert/deinsert limited amounts of lithium (∼0.3 Li(+)) in a potential window ranging from 2.5 to 4.5 V vs. Li(+)/Li(0). We demonstrate, via electron paramagnetic resonance (EPR), that such an electrochemical activity centered near 4.25 V vs. Li(+)/Li(0) is associated with the Cu(3+)/Cu(2+) redox couple, confirmed by density functional theory (DFT) calculations. Another specificity of this compound lies in its different electrochemical behavior when cycled down to 1 V vs. Li(+)/Li(0) which leads to the extrusion of elemental copper via a conversion type reaction as deduced by transmission electron microscopy (TEM). Lastly, we probe the ionic conductivity by means of AC and DC impedance measurements as a function of temperature and show that Li6CuB4O10 undergoes a reversible structural transition around 350 °C, leading to a surprisingly high ionic conductivity of ∼1.4 mS cm(-1) at 500 °C. PMID:27189653

  10. Purification of charybdotoxine, a specific inhibitor of the high-conductance Ca/sup 2 +/-activated K/sup +/ channel

    SciTech Connect

    Smith, C.; Phillips, M.; Miller, C.

    1986-11-05

    Charybdotoxim is a high-affinity specific inhibitor of the high-conductance Ca/sup 2 +/-activated K/sup +/ channel found in the plasma membranes of many vertebrate cell types. Using Ca/sup 2 +/-activated K/sup +/ channels reconstituted into planar lipid bilayer membranes as an assay, the authors have purified the toxin from the venom of the scorpion Leiurus quinquestriatus by a two-step procedure involving chromatofocusing on SP-Sephadex, followed by reversed-phase high-performance liquid chromatography. Charybdotoxin is shown to be a highly basic protein with a mass of 10 kDa. Under the standard assay conditions, the purified toxin inhibits the Ca/sup 2 +/-activated K/sup +/ channel with an apparent dissociation constant of 3.5 nM. The protein is unusually stable, with inhibitory potency being insensitive to boiling or exposure to organic solvents. The toxin's activity is sensitive to chymotrypsin treatment and to acylation of lysine groups. The protein may be radioiodinated without loss of activity.

  11. Recommendations for conducting controlled clinical studies of dental restorative materials. Science Committee Project 2/98--FDI World Dental Federation study design (Part I) and criteria for evaluation (Part II) of direct and indirect restorations including onlays and partial crowns.

    PubMed

    Hickel, Reinhard; Roulet, Jean-François; Bayne, Stephen; Heintze, Siegward D; Mjör, Ivar A; Peters, Mathilde; Rousson, Valentin; Randall, Ros; Schmalz, Gottfried; Tyas, Martin; Vanherle, Guido

    2007-01-01

    About 35 years ago, Ryge provided a practical approach to the evaluation of the clinical performance of restorative materials. This systematic approach was soon universally accepted. While that methodology has served us well, a large number of scientific methodologies and more detailed questions have arisen that require more rigor. Current restorative materials have vastly improved clinical performance, and any changes over time are not easily detected by the limited sensitivity of the Ryge criteria in short-term clinical investigations. However, the clinical evaluation of restorations not only involves the restorative material per se but also different operative techniques. For instance, a composite resin may show good longevity data when applied in conventional cavities but not in modified operative approaches. Insensitivity, combined with the continually evolving and nonstandard investigator modifications of the categories, scales, and reporting methods, has created a body of literature that is extremely difficult to interpret meaningfully. In many cases, the insensitivity of the original Ryge methods leads to misinterpretation as good clinical performance. While there are many good features of the original system, it is now time to move on to a more contemporary one. The current review approaches this challenge in two ways: (1) a proposal for a modern clinical testing protocol for controlled clinical trials, and (2) an in-depth discussion of relevant clinical evaluation parameters, providing 84 references that are primarily related to issues or problems for clinical research trials. Together, these two parts offer a standard for the clinical testing of restorative materials/procedures and provide significant guidance for research teams in the design and conduct of contemporary clinical trials. Part 1 of the review considers the recruitment of subjects, restorations per subject, clinical events, validity versus bias, legal and regulatory aspects, rationales for

  12. A3 domain region 1803-1818 contributes to the stability of activated factor VIII and includes a binding site for activated factor IX.

    PubMed

    Bloem, Esther; Meems, Henriet; van den Biggelaar, Maartje; Mertens, Koen; Meijer, Alexander B

    2013-09-01

    A recent chemical footprinting study in our laboratory suggested that region 1803-1818 might contribute to A2 domain retention in activated factor VIII (FVIIIa). This site has also been implicated to interact with activated factor IX (FIXa). Asn-1810 further comprises an N-linked glycan, which seems incompatible with a role of the amino acids 1803-1818 for FIXa or A2 domain binding. In the present study, FVIIIa stability and FIXa binding were evaluated in a FVIII-N1810C variant, and two FVIII variants in which residues 1803-1810 and 1811-1818 are replaced by the corresponding residues of factor V (FV). Enzyme kinetic studies showed that only FVIII/FV 1811-1818 has a decreased apparent binding affinity for FIXa. Flow cytometry analysis indicated that fluorescent FIXa exhibits impaired complex formation with only FVIII/FV 1811-1818 on lipospheres. Site-directed mutagenesis revealed that Phe-1816 contributes to the interaction with FIXa. To evaluate FVIIIa stability, the FVIII/FV chimeras were activated by thrombin, and the decline in cofactor function was followed over time. FVIII/FV 1803-1810 and FVIII/FV 1811-1818 but not FVIII-N1810C showed a decreased FVIIIa half-life. However, when the FVIII variants were activated in presence of FIXa, only FVIII/FV 1811-1818 demonstrated an enhanced decline in cofactor function. Surface plasmon resonance analysis revealed that the FVIII variants K1813A/K1818A, E1811A, and F1816A exhibit enhanced dissociation after activation. The results together demonstrate that the glycan at 1810 is not involved in FVIII cofactor function, and that Phe-1816 of region 1811-1818 contributes to FIXa binding. Both regions 1803-1810 and 1811-1818 contribute to FVIIIa stability.

  13. A3 domain region 1803-1818 contributes to the stability of activated factor VIII and includes a binding site for activated factor IX.

    PubMed

    Bloem, Esther; Meems, Henriet; van den Biggelaar, Maartje; Mertens, Koen; Meijer, Alexander B

    2013-09-01

    A recent chemical footprinting study in our laboratory suggested that region 1803-1818 might contribute to A2 domain retention in activated factor VIII (FVIIIa). This site has also been implicated to interact with activated factor IX (FIXa). Asn-1810 further comprises an N-linked glycan, which seems incompatible with a role of the amino acids 1803-1818 for FIXa or A2 domain binding. In the present study, FVIIIa stability and FIXa binding were evaluated in a FVIII-N1810C variant, and two FVIII variants in which residues 1803-1810 and 1811-1818 are replaced by the corresponding residues of factor V (FV). Enzyme kinetic studies showed that only FVIII/FV 1811-1818 has a decreased apparent binding affinity for FIXa. Flow cytometry analysis indicated that fluorescent FIXa exhibits impaired complex formation with only FVIII/FV 1811-1818 on lipospheres. Site-directed mutagenesis revealed that Phe-1816 contributes to the interaction with FIXa. To evaluate FVIIIa stability, the FVIII/FV chimeras were activated by thrombin, and the decline in cofactor function was followed over time. FVIII/FV 1803-1810 and FVIII/FV 1811-1818 but not FVIII-N1810C showed a decreased FVIIIa half-life. However, when the FVIII variants were activated in presence of FIXa, only FVIII/FV 1811-1818 demonstrated an enhanced decline in cofactor function. Surface plasmon resonance analysis revealed that the FVIII variants K1813A/K1818A, E1811A, and F1816A exhibit enhanced dissociation after activation. The results together demonstrate that the glycan at 1810 is not involved in FVIII cofactor function, and that Phe-1816 of region 1811-1818 contributes to FIXa binding. Both regions 1803-1810 and 1811-1818 contribute to FVIIIa stability. PMID:23884417

  14. A3 Domain Region 1803–1818 Contributes to the Stability of Activated Factor VIII and Includes a Binding Site for Activated Factor IX

    PubMed Central

    Bloem, Esther; Meems, Henriet; van den Biggelaar, Maartje; Mertens, Koen; Meijer, Alexander B.

    2013-01-01

    A recent chemical footprinting study in our laboratory suggested that region 1803–1818 might contribute to A2 domain retention in activated factor VIII (FVIIIa). This site has also been implicated to interact with activated factor IX (FIXa). Asn-1810 further comprises an N-linked glycan, which seems incompatible with a role of the amino acids 1803–1818 for FIXa or A2 domain binding. In the present study, FVIIIa stability and FIXa binding were evaluated in a FVIII-N1810C variant, and two FVIII variants in which residues 1803–1810 and 1811–1818 are replaced by the corresponding residues of factor V (FV). Enzyme kinetic studies showed that only FVIII/FV 1811–1818 has a decreased apparent binding affinity for FIXa. Flow cytometry analysis indicated that fluorescent FIXa exhibits impaired complex formation with only FVIII/FV 1811–1818 on lipospheres. Site-directed mutagenesis revealed that Phe-1816 contributes to the interaction with FIXa. To evaluate FVIIIa stability, the FVIII/FV chimeras were activated by thrombin, and the decline in cofactor function was followed over time. FVIII/FV 1803–1810 and FVIII/FV 1811–1818 but not FVIII-N1810C showed a decreased FVIIIa half-life. However, when the FVIII variants were activated in presence of FIXa, only FVIII/FV 1811–1818 demonstrated an enhanced decline in cofactor function. Surface plasmon resonance analysis revealed that the FVIII variants K1813A/K1818A, E1811A, and F1816A exhibit enhanced dissociation after activation. The results together demonstrate that the glycan at 1810 is not involved in FVIII cofactor function, and that Phe-1816 of region 1811–1818 contributes to FIXa binding. Both regions 1803–1810 and 1811–1818 contribute to FVIIIa stability. PMID:23884417

  15. Modeling the influence of the VV delay for CRT on the electrical activation patterns in absence of conduction through the AV node

    NASA Astrophysics Data System (ADS)

    Romero, D. A.; Sebastián, Rafael; Plank, Gernot; Vigmond, Edward J.; Frangi, Alejandro F.

    2008-03-01

    From epidemiological studies, it has been shown that 0.2% of men and 0.1% of women suffer from a degree of atrioventricular (AV) block. In recent years, the palliative treatment for third degree AV block has included Cardiac Resynchronization Therapy (CRT). It was found that patients show more clinical improvement in the long term with CRT compared with single chamber devices. Still, an important group of patients does not improve their hemodynamic function as much as could be expected. A better understanding of the basis for optimizing the devices settings (among which the VV delay) will help to increase the number of responders. In this work, a finite element model of the left and right ventricles was generated using an atlas-based approach for their segmentation, which includes fiber orientation. The electrical activity was simulated with the electrophysiological solver CARP, using the Ten Tusscher et al. ionic model for the myocardium, and the DiFrancesco-Noble for Purkinje fibers. The model is representative of a patient without dilated or ischemic cardiomyopathy. The simulation results were analyzed for total activation times and latest activated regions at different VV delays and pre-activations (RV pre-activated, LV pre-activated). To optimize the solution, simulations are compared against the His-Purkinje network activation (normal physiological conduction), and interventricular septum activation (as collision point for the two wave fronts). The results were analyzed using Pearson's coefficient of correlation for point to point comparisons between simulation cases. The results of this study contribute to gain insight on the VV delay and how its adjustment might influence response to CRT and how it can be used to optimize the treatment.

  16. Gain control of synaptic response function in cerebellar nuclear neurons by a calcium-activated potassium conductance.

    PubMed

    Feng, Steven Si; Lin, Risa; Gauck, Volker; Jaeger, Dieter

    2013-10-01

    Small conductance Ca(2+)-activated potassium (SK) current provides an important modulator of excitatory synaptic transmission, which undergoes plastic regulation via multiple mechanisms. We examined whether inhibitory input processing is also dependent on SK current in the cerebellar nuclei (CN) where inhibition provides the only route of information transfer from the cerebellar cortical Purkinje cells. We employed dynamic clamping in conjunction with computer simulations to address this question. We found that SK current plays a critical role in the inhibitory synaptic control of spiking output. Specifically, regulation of SK current density resulted in a gain control of spiking output, such that low SK current promoted large output signaling for large inhibitory cell input fluctuations due to Purkinje cell synchronization. In contrast, smaller nonsynchronized Purkinje cell input fluctuations were not amplified. Regulation of SK density in the CN therefore would likely lead to important consequences for the transmission of synchronized Purkinje cell activity to the motor system. PMID:23605187

  17. Role of the conducting layer substrate on TiO2 nucleation when using microwave activated chemical bath deposition

    NASA Astrophysics Data System (ADS)

    Zumeta, I.; Espinosa, R.; Ayllón, J. A.; Vigil, E.

    2002-12-01

    Nanostructured TiO2 is used in novel dye sensitized solar cells. Because of their interaction with light, thin TiO2 films are also used as coatings for self-cleaning glasses and tiles. Microwave activated chemical bath deposition represents a simple and cost-effective way to obtain nanostructured TiO2 films. It is important to study, in this technique, the role of the conducting layer used as the substrate. The influence of microwave-substrate interactions on TiO2 deposition is analysed using different substrate positions, employing substrates with different conductivities, and also using different microwave radiation powers for film deposition. We prove that a common domestic microwave oven with a large cavity and inhomogeneous radiation field can be used with equally satisfactory results. The transmittance spectra of the obtained films were studied and used to analyse film thickness and to obtain gap energy values. The results, regarding different indium-tin oxide resistivities and different substrate positions in the oven cavity, show that the interaction of the microwave field with the conducting layer is determinant in layer deposition. It has also been found that film thickness increases with the power of the applied radiation while the gap energies of the TiO2 films decrease approaching the 3.2 eV value reported for bulk anatase. This indicates that these films are not crystalline and it agrees with x-ray spectra that do not reveal any peak.

  18. Preschool Curriculum: A Child Centered Curriculum of Concepts and Activities Including All of the CDA Functional Areas--Bi-lingual and Home Activities.

    ERIC Educational Resources Information Center

    Cunningham, Dorothy, Comp.

    This preschool resource curriculum, intended for use in a Head Start center, was written to correspond with a work plan and curriculum for children 3 to 5 years of age. The units included in the curriculum guide are aimed at integrating growth experiences with the learning of basic skills. Each of the 16 units contains material related to each of…

  19. Effects of Lifestyle Interventions That Include a Physical Activity Component in Class II and III Obese Individuals: A Systematic Review and Meta-Analysis

    PubMed Central

    Baillot, Aurélie; Romain, Ahmed J.; Boisvert-Vigneault, Katherine; Audet, Mélisa; Baillargeon, Jean Patrice; Dionne, Isabelle J.; Valiquette, Louis; Chakra, Claire Nour Abou; Avignon, Antoine; Langlois, Marie-France

    2015-01-01

    Background In class II and III obese individuals, lifestyle intervention is the first step to achieve weight loss and treat obesity-related comorbidities before considering bariatric surgery. A systematic review, meta-analysis, and meta-regression were performed to assess the impact of lifestyle interventions incorporating a physical activity (PA) component on health outcomes of class II and III obese individuals. Methods An electronic search was conducted in 4 databases (Medline, Scopus, CINAHL and Sportdiscus). Two independent investigators selected original studies assessing the impact of lifestyle interventions with PA components on anthropometric parameters, cardiometabolic risk factors (fat mass, blood pressure, lipid and glucose metabolism), behaviour modification (PA and nutritional changes), and quality of life in adults with body mass index (BMI) ≥ 35 kg/m2. Estimates were pooled using a random-effect model (DerSimonian and Laird method). Heterogeneity between studies was assessed by the Cochran’s chi-square test and quantified through an estimation of the I². Results Of the 3,170 identified articles, 56 met our eligibility criteria, with a large majority of uncontrolled studies (80%). The meta-analysis based on uncontrolled studies showed significant heterogeneity among all included studies. The pooled mean difference in weight loss was 8.9 kg (95% CI, 10.2–7.7; p < 0.01) and 2.8 kg/m² in BMI loss (95% CI, 3.4–2.2; p < 0.01). Long-term interventions produced superior weight loss (11.3 kg) compared to short-term (7.2 kg) and intermediate-term (8.0 kg) interventions. A significant global effect of lifestyle intervention on fat mass, waist circumference, blood pressure, total cholesterol, LDL-C, triglycerides and fasting insulin was found (p<0.01), without significant effect on HDL-C and fasting blood glucose. Conclusions Lifestyle interventions incorporating a PA component can improve weight and various cardiometabolic risk factors in class II

  20. Rapid binding of a cationic active site inhibitor to wild type and mutant mouse acetylcholinesterase: Brownian dynamics simulation including diffusion in the active site gorge.

    PubMed

    Tara, S; Elcock, A H; Kirchhoff, P D; Briggs, J M; Radic, Z; Taylor, P; McCammon, J A

    1998-12-01

    It is known that anionic surface residues play a role in the long-range electrostatic attraction between acetylcholinesterase and cationic ligands. In our current investigation, we show that anionic residues also play an important role in the behavior of the ligand within the active site gorge of acetylcholinesterase. Negatively charged residues near the gorge opening not only attract positively charged ligands from solution to the enzyme, but can also restrict the motion of the ligand once it is inside of the gorge. We use Brownian dynamics techniques to calculate the rate constant kon, for wild type and mutant acetylcholinesterase with a positively charged ligand. These calculations are performed by allowing the ligand to diffuse within the active site gorge. This is an extension of previously reported work in which a ligand was allowed to diffuse only to the enzyme surface. By setting the reaction criteria for the ligand closer to the active site, better agreement with experimental data is obtained. Although a number of residues influence the movement of the ligand within the gorge, Asp74 is shown to play a particularly important role in this function. Asp74 traps the ligand within the gorge, and in this way helps to ensure a reaction.

  1. The M34A mutant of Connexin26 reveals active conductance states in pore-suspending membranes

    PubMed Central

    Gaßmann, Oliver; Kreir, Mohamed; Ambrosi, Cinzia; Pranskevich, Jennifer; Oshima, Atsunori; Röling, Christian; Sosinsky, Gina; Fertig, Niels; Steinem, Claudia

    2009-01-01

    Connexin26 (Cx26) is a member of the connexin family, the building blocks for gap junction intercellular channels. These dodecameric assemblies are involved in gap junction-mediated cell-cell communication allowing the passage of ions and small molecules between two neighboring cells. Mutations in Cx26 lead to the disruption of gap junction-mediated intercellular communication with consequences such as hearing loss and skin disorders. We show here that a mutant of Cx26, M34A, forms an active hemichannel in lipid bilayer experiments. A comparison with the Cx26 wild-type is presented. Two different techniques using micro/nano-structured substrates for the formation of pore-suspending lipid membranes are used. We reconstituted the Cx26 wild-type and Cx26M34A into artificial lipid bilayers and observed single channel activity for each technique, with conductance levels of around 35, 70 and 165 pS for the wildtype. The conductance levels of Cx26M34A were found at around 45 and 70 pS. PMID:19236918

  2. A poultry-intestinal isolate of Campylobacter jejuni produces a bacteriocin (CUV-3) active against a range of Gram positive bacterial pathogens including Clostridium perfringens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A newly isolated bacteriocin, CUV-3, produced by a poultry cecal isolate of Campylobacter jejuni strain CUV-3 had inhibitory activity against several Gram positive bacteria including Clostridium perfringens (38 strains), Staphylococcus aureus, Staph.epidermidis and Listeria monocytogenes. The pept...

  3. Including Youth with Intellectual Disabilities in Health Promotion Research: Development and Reliability of a Structured Interview to Assess the Correlates of Physical Activity among Youth

    ERIC Educational Resources Information Center

    Curtin, Carol; Bandini, Linda G.; Must, Aviva; Phillips, Sarah; Maslin, Melissa C. T.; Lo, Charmaine; Gleason, James M.; Fleming, Richard K.; Stanish, Heidi I.

    2016-01-01

    Background: The input of youth with intellectual disabilities in health promotion and health disparities research is essential for understanding their needs and preferences. Regular physical activity (PA) is vital for health and well-being, but levels are low in youth generally, including those with intellectual disabilities. Understanding the…

  4. Time Use Differences in Activity Participation among Children 4-5 Years Old with and without the Risk of Developing Conduct Problems

    ERIC Educational Resources Information Center

    Yu, Mong-Lin; Ziviani, Jenny; Baxter, Janeen; Haynes, Michele

    2012-01-01

    Conduct problems in childhood are associated with the way in which children engage in daily activities. Research, to date, on conduct problems in relation to time use has primarily focused on school aged children and their participation in discrete activities such as watching TV and sport. The purpose of the present study is to determine if…

  5. 26 CFR 1.367(a)-2 - Exception for transfers of property for use in the active conduct of a trade or business.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 4 2013-04-01 2013-04-01 false Exception for transfers of property for use in the active conduct of a trade or business. 1.367(a)-2 Section 1.367(a)-2 Internal Revenue INTERNAL...) Effects on Corporation § 1.367(a)-2 Exception for transfers of property for use in the active conduct of...

  6. 26 CFR 1.367(a)-2 - Exception for transfers of property for use in the active conduct of a trade or business.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 4 2012-04-01 2012-04-01 false Exception for transfers of property for use in the active conduct of a trade or business. 1.367(a)-2 Section 1.367(a)-2 Internal Revenue INTERNAL...) Effects on Corporation § 1.367(a)-2 Exception for transfers of property for use in the active conduct of...

  7. 25 CFR 292.13 - When can a tribe conduct gaming activities on newly acquired lands that do not qualify under one...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false When can a tribe conduct gaming activities on newly... 292.13 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ECONOMIC ENTERPRISES GAMING ON....13 When can a tribe conduct gaming activities on newly acquired lands that do not qualify under...

  8. 25 CFR 292.13 - When can a tribe conduct gaming activities on newly acquired lands that do not qualify under one...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false When can a tribe conduct gaming activities on newly... 292.13 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ECONOMIC ENTERPRISES GAMING ON....13 When can a tribe conduct gaming activities on newly acquired lands that do not qualify under...

  9. Multiple types of voltage-dependent Ca2+-activated K+ channels of large conductance in rat brain synaptosomal membranes.

    PubMed Central

    Farley, J.; Rudy, B.

    1988-01-01

    K+-selective ion channels from a mammalian brain synaptosomal membrane preparation were inserted into planar phospholipid bilayers on the tips of patch-clamp pipettes, and single-channel currents were measured. Multiple distinct classes of K+ channels were observed. We have characterized and described the properties of several types of voltage-dependent, Ca2+-activated K+ channels of large single-channel conductance (greater than 50 pS in symmetrical KCl solutions). One class of channels (Type I) has a 200-250-pS single-channel conductance. It is activated by internal calcium concentrations greater than 10(-7) M, and its probability of opening is increased by membrane depolarization. This channel is blocked by 1-3 mM internal concentrations of tetraethylammonium (TEA). These channels are similar to the BK channel described in a variety of tissues. A second novel group of voltage-dependent, Ca2+-activated K+ channels was also studied. These channels were more sensitive to internal calcium, but less sensitive to voltage than the large (Type I) channel. These channels were minimally affected by internal TEA concentrations of 10 mM, but were blocked by a 50 mM concentration. In this class of channels we found a wide range of relatively large unitary channel conductances (65-140 pS). Within this group we have characterized two types (75-80 pS and 120-125 pS) that also differ in gating kinetics. The various types of voltage-dependent, Ca2+-activated K+ channels described here were blocked by charybdotoxin added to the external side of the channel. The activity of these channels was increased by exposure to nanomolar concentrations of the catalytic subunit of cAMP-dependent protein kinase. These results indicate that voltage-dependent, charybdotoxin-sensitive Ca2+-activated K+ channels comprise a class of related, but distinguishable channel types. Although the Ca2+-activated (Type I and II) K+ channels can be distinguished by their single-channel properties, both could

  10. Effect of Phosphatidylserine on Unitary Conductance and Ba2+ Block of the BK Ca2+–activated K+ Channel

    PubMed Central

    Park, Jin Bong; Kim, Hee Jeong; Ryu, Pan Dong; Moczydlowski, Edward

    2003-01-01

    Incorporation of BK Ca2+–activated K+ channels into planar bilayers composed of negatively charged phospholipids such as phosphatidylserine (PS) or phosphatidylinositol (PI) results in a large enhancement of unitary conductance (gch) in comparison to BK channels in bilayers formed from the neutral zwitterionic lipid, phospatidylethanolamine (PE). Enhancement of gch by PS or PI is inversely dependent on KCl concentration, decreasing from 70% at 10 mM KCl to 8% at 1,000 mM KCl. This effect was explained previously by a surface charge hypothesis (Moczydlowski, E., O. Alvarez, C. Vergara, and R. Latorre. 1985. J. Membr. Biol. 83:273–282), which attributed the conductance enhancement to an increase in local K+ concentration near the entryways of the channel. To test this hypothesis, we measured the kinetics of block by external and internal Ba2+, a divalent cation that is expected to respond strongly to changes in surface electrostatics. We observed little or no effect of PS on discrete blocking kinetics by external and internal Ba2+ at 100 mM KCl and only a small enhancement of discrete and fast block by external Ba2+ in PS-containing membranes at 20 mM KCl. Model calculations of effective surface potential sensed by the K+ conduction and Ba2+-blocking reactions using the Gouy-Chapman-Stern theory of lipid surface charge do not lend support to a simple electrostatic mechanism that predicts valence-dependent increase of local cation concentration. The results imply that the conduction pore of the BK channel is electrostatically insulated from the lipid surface, presumably by a lateral distance of separation (>20 Å) from the lipid head groups. The lack of effect of PS on apparent association and dissociation rates of Ba2+ suggest that lipid modulation of K+ conductance is preferentially coupled through conformational changes of the selectivity filter region that determine the high K+ flux rate of this channel relative to other cations. We discuss possible mechanisms

  11. Measurement of factor VIII activity using one-stage clotting assay: a calibration curve has not to be systematically included in each run.

    PubMed

    Lattes, S; Appert-Flory, A; Fischer, F; Jambou, D; Toulon, P

    2011-01-01

    Coagulation factor VIII (FVIII) is usually evaluated using activated partial thromboplastin time-based one-stage clotting assays. Guidelines for clotting factor assays indicate that a calibration curve should be included each time the assay is performed. Therefore, FVIII measurement is expensive, reagent- and time-consuming. The aim of this study was to compare FVIII activities obtained using the same fully automated assay that was calibrated once (stored calibration curve) or each time the assay was performed. Unique lots of reagents were used throughout the study. We analysed 255 frozen plasma samples from patients who were prescribed FVIII measurement including treated and untreated haemophilia A patients. Twenty-six runs were performed on a 28-week period, each including four lyophilized control and at most 10 patient plasma samples. In control samples, FVIII activities were not significantly different when the assay was performed using the stored calibration curve or was daily calibrated. The same applied to FVIII activities in patient plasma samples that were not significantly different throughout the measuring range of activities [68.3% (<1-179) vs. 67.6% (<1-177), P=0.48] and no relevant bias could be demonstrated when data were compared according to Bland and Altman. These results suggest that in the studied technical conditions, performing the FVIII assay using a stored calibration curve is reliable, for at least 6 months. Therefore, as far as the same lots of reagents are used, it is not mandatory to include a calibration curve each time the FVIII assay was performed. However, this strategy has to be validated if the assay is performed in different technical conditions.

  12. P2Y2 receptor activation decreases blood pressure via intermediate conductance potassium channels and connexin 37

    PubMed Central

    Dominguez Rieg, J. A.; Burt, J. M.; Ruth, P.; Rieg, T.

    2015-01-01

    Aims Nucleotides are important paracrine regulators of vascular tone. We previously demonstrated that activation of P2Y2 receptors causes an acute, NO-independent decrease in blood pressure, indicating this signalling pathway requires an endothelial-derived hyperpolarization (EDH) response. To define the mechanisms by which activation of P2Y2 receptors initiates EDH and vasodilation, we studied intermediate-conductance (KCa3.1, expressed in endothelial cells) and big-conductance potassium channels (KCa1.1, expressed in smooth muscle cells) as well as components of the myoendothelial gap junction, connexins 37 and 40 (Cx37, Cx40), all hypothesized to be part of the EDH response. Methods We compared the effects of a P2Y2/4 receptor agonist in wild-type (WT) mice and in mice lacking KCa3.1, KCa1.1, Cx37 or Cx40 under anaesthesia, while monitoring intra-arterial blood pressure and heart rate. Results Acute activation of P2Y2/4 receptors (0.01–3 mg kg−1 body weight i.v.) caused a biphasic blood pressure response characterized by a dose-dependent and rapid decrease in blood pressure in WT (maximal response % of baseline at 3 mg kg−1: −38 ± 1%) followed by a consecutive increase in blood pressure (+44 ± 11%). The maximal responses in KCa3.1−/− and Cx37−/− were impaired (−13 ± 5, +17 ± 7 and −27 ± 1, +13 ± 3% respectively), whereas the maximal blood pressure decrease in response to acetylcholine at 3 µg kg−1 was not significantly different (WT: −53 ± 3%; KCa3.1−/−: −52 ± 3; Cx37−/−: −53 ± 3%). KCa1.1−/− and Cx40−/− showed an identical biphasic response to P2Y2/4 receptor activation compared to WT. Conclusions The data suggest that the P2Y2/4 receptor activation elicits blood pressure responses via distinct mechanisms involving KCa3.1 and Cx37. PMID:25545736

  13. Electrochemical properties and electrocatalytic activity of conducting polymer/copper nanoparticles supported on reduced graphene oxide composite

    NASA Astrophysics Data System (ADS)

    Ehsani, Ali; Jaleh, Babak; Nasrollahzadeh, Mahmoud

    2014-07-01

    Reduced graphene oxide (rGO) was used to support Cu nanoparticles. As electro-active electrodes for supercapacitors composites of reduced graphene oxide/Cu nanoparticles (rGO/CuNPs) and polytyramine (PT) with good uniformity are prepared by electropolymerization. Composite of rGO/CuNPs-PT was synthesized by cyclic voltammetry (CV) methods and electrochemical properties of film were investigated by using electrochemical techniques. The results show that, the rGO/CuNPs-PT/G has better capacitance performance. This is mainly because of the really large surface area and the better electronic and ionic conductivity of rGO/CuNPs-PT/G, which lead to greater double-layer capacitance and faradic pseudo capacitance. Modified graphite electrodes (rGO/CuNPs-PT/G) were examined for their redox process and electrocatalytic activities towards the oxidation of methanol in alkaline solutions. The methods of cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) were employed. In comparison with a Cu-PT/G (Graphite), rGO/CuNPs-PT/G modified electrode shows a significantly higher response for methanol oxidation. A mechanism based on the electro-chemical generation of Cu(III) active sites and their subsequent consumptions by methanol have been discussed.

  14. Onsite medical rounds and fact-finding activities conducted by Nippon Medical School in Miyagi prefecture after the Great East Japan Earthquake 2011.

    PubMed

    Fuse, Akira; Igarashi, Yutaka; Tanaka, Toshihiko; Kim, Shiei; Tsujii, Atsuko; Kawai, Makoto; Yokota, Hiroyuki

    2011-01-01

    This report describes our onsite medical rounds and fact-finding activities conducted in the acute phase and medical relief work conducted in the subacute phase in Miyagi prefecture following the Great East Japan Earthquake and subsequent tsunami that occurred off northeastern Honshu on March 11, 2011. As part of the All-Japan Hospital Association medical team deployed to the disaster area, a Nippon Medical School team conducted fact-finding and onsite medical rounds and evaluated basic life and medical needs in the affected areas of Shiogama and Tagajo. We performed triage for more than 2,000 casualties, but in our medical rounds of hospitals, clinics, and nursing homes, we found no severely injured person but did find 1 case of hyperglycemia. We conducted medical rounds at evacuation shelters in Kesennuma City during the subacute phase of the disaster, from March 17 through June 1, as part of the Tokyo Medical Association medical teams deployed. Sixty-seven staff members (17 teams), including 46 physicians, 11 nurses, 3 pharmacists, and 1 clinical psychotherapist, joined this mission. Most patients complained of a worsening of symptoms of preexisting conditions, such as hypertension, respiratory problems, and diabetes, rather than of medical problems specifically related to the tsunami. In the acute phase of the disaster, the information infrastructure was decimated and we could not obtain enough information about conditions in the affected areas, such as how many persons were severely injured, how severely lifeline services had been damaged, and what was lacking. To start obtaining this information, we conducted medical rounds. This proved to be a good decision, as we found many injured persons in evacuation shelters without medication, communication devices, or transportation. Also, basic necessities for life, such as water and food, were lacking. We were able to evaluate these basic needs and inform local disaster headquarters of them. In Kesennuma City, we

  15. Freeze-thaw stress: effects of temperature on hydraulic conductivity and ultrasonic activity in ten woody angiosperms.

    PubMed

    Charrier, Guillaume; Charra-Vaskou, Katline; Kasuga, Jun; Cochard, Hervé; Mayr, Stefan; Améglio, Thierry

    2014-02-01

    Freeze-thaw events can affect plant hydraulics by inducing embolism. This study analyzed the effect of temperature during the freezing process on hydraulic conductivity and ultrasonic emissions (UE). Stems of 10 angiosperms were dehydrated to a water potential at 12% percentage loss of hydraulic conductivity (PLC) and exposed to freeze-thaw cycles. The minimal temperature of the frost cycle correlated positively with induced PLC, whereby species with wider conduits (hydraulic diameter) showed higher freeze-thaw-induced PLC. Ultrasonic activity started with the onset of freezing and increased with decreasing subzero temperatures, whereas no UE were recorded during thawing. The temperature at which 50% of UE were reached varied between -9.1°C and -31.0°C across species. These findings indicate that temperatures during freezing are of relevance for bubble formation and air seeding. We suggest that species-specific cavitation thresholds are reached during freezing due to the temperature-dependent decrease of water potential in the ice, while bubble expansion and the resulting PLC occur during thawing. UE analysis can be used to monitor the cavitation process and estimate freeze-thaw-induced PLC.

  16. Summary of activities of the life cycle costing workshop conducted by the Environmental Restoration Program of Oak Ridge National Laboratory

    SciTech Connect

    Not Available

    1992-08-01

    A five-day life cycle workshop was conducted by the Environmental Restoration (FR) Program of Oak Ridge National Laboratory (ORNL) to develop appropriate remediation scenarios for each Waste Area Grouping (WAG) at ORNL and to identify associated data needs (e.g., remedial investigations, special studies, and technology demonstrations) and required interfaces. Workshop participants represented the Department of Energy, Martin Marietta Energy Systems, Inc., Bechtel National, Radian Corporation, EBASCO Corporation, and M-K Ferguson. The workshop was used to establish a technical basis for remediation activities at each WAG. The workshop results are documented in this report and provide the baseline for estimating the technical scope for each WAG. The scope and associated budgets and schedules will be summarized in baseline reports for each WAG, which, in turn, will be compiled into an overall strategy document for ORNL ER.

  17. Structural basis for calcium and magnesium regulation of a large conductance calcium-activated potassium channel with β1 subunits.

    PubMed

    Liu, Hao-Wen; Hou, Pan-Pan; Guo, Xi-Ying; Zhao, Zhi-Wen; Hu, Bin; Li, Xia; Wang, Lu-Yang; Ding, Jiu-Ping; Wang, Sheng

    2014-06-13

    Large conductance Ca(2+)- and voltage-activated potassium (BK) channels, composed of pore-forming α subunits and auxiliary β subunits, play important roles in diverse physiological activities. The β1 is predominately expressed in smooth muscle cells, where it greatly enhances the Ca(2+) sensitivity of BK channels for proper regulation of smooth muscle tone. However, the structural basis underlying dynamic interaction between BK mSlo1 α and β1 remains elusive. Using macroscopic ionic current recordings in various Ca(2+) and Mg(2+) concentrations, we identified two binding sites on the cytosolic N terminus of β1, namely the electrostatic enhancing site (mSlo1(K392,R393)-β1(E13,T14)), increasing the calcium sensitivity of BK channels, and the hydrophobic site (mSlo1(L906,L908)-β1(L5,V6,M7)), passing the physical force from the Ca(2+) bowl onto the enhancing site and S6 C-linker. Dynamic binding of these sites affects the interaction between the cytosolic domain and voltage-sensing domain, leading to the reduction of Mg(2+) sensitivity. A comprehensive structural model of the BK(mSlo1 α-β1) complex was reconstructed based on these functional studies, which provides structural and mechanistic insights for understanding BK gating. PMID:24764303

  18. Identification of the functional binding pocket for compounds targeting small-conductance Ca2+-activated potassium channels

    PubMed Central

    Zhang, Miao; Pascal, John M.; Schumann, Marcel; Armen, Roger S.; Zhang, Ji-fang

    2012-01-01

    Small- and intermediate-conductance Ca2+-activated potassium channels, activated by Ca2+-bound calmodulin, play an important role in regulating membrane excitability. These channels are also linked to clinical abnormalities. A tremendous amount of effort has been devoted to developing small molecule compounds targeting these channels. However, these compounds often suffer from low potency and lack of selectivity, hindering their potentials for clinical use. A key contributing factor is the lack of knowledge of the binding site(s) for these compounds. Here we demonstrate by X-ray crystallography that the binding pocket for the compounds of the 1-EBIO class is located at the calmodulin-channel interface. We show that, based on structure data and molecular docking, mutations of the channel can effectively change the potency of these compounds. Our results provide insight into the molecular nature of the binding pocket and its contribution to the potency and selectivity of the compounds of the 1-EBIO class. PMID:22929778

  19. The effect of apamin, a small conductance calcium activated potassium (SK) channel blocker, on a mouse model of neurofibromatosis 1.

    PubMed

    Kallarackal, Angy J; Simard, J Marc; Bailey, Aileen M

    2013-01-15

    Neurofibromatosis 1 (NF1) is a common genetic disorder known to cause a variety of physiological symptoms such as the formation of both benign and malignant tumors, and is also known to cause visuospatial learning deficits. Mouse models of NF1 show increased GTP activation of ras which may alter K+ channels. One candidate K+ channel that may contribute to deficits in NF1 is the SK (small conductance calcium-activated potassium) channel due to its role in regulation of long term potentiation (LTP), a mechanism of learning which has been shown to be impaired in Nf1(+/-) mice. We found that administration of apamin (SK antagonist) either through i.p. injection or micro-osmotic pump to Nf1(+/-) mice significantly improved performance on the water maze task in comparison to saline treated Nf1(+/-) mice on the third day of training and on the corresponding probe test. In this study we demonstrate a possible mechanism for the learning deficits seen in Nf1(+/-) mice and a possible drug therapy for rescuing these deficits. PMID:22983217

  20. Muscle fiber conduction velocity and fractal dimension of EMG during fatiguing contraction of young and elderly active men.

    PubMed

    Boccia, Gennaro; Dardanello, Davide; Beretta-Piccoli, Matteo; Cescon, Corrado; Coratella, Giuseppe; Rinaldo, Nicoletta; Barbero, Marco; Lanza, Massimo; Schena, Federico; Rainoldi, Alberto

    2016-01-01

    Over the past decade, linear and nonlinear surface electromyography (EMG) variables highlighting different components of fatigue have been developed. In this study, we tested fractal dimension (FD) and conduction velocity (CV) rate of changes as descriptors, respectively, of motor unit synchronization and peripheral manifestations of fatigue. Sixteen elderly (69  ±  4 years) and seventeen young (23  ±  2 years) physically active men (almost 3-5 h of physical activity per week) executed one knee extensor contraction at 70% of a maximal voluntary contraction for 30 s. Muscle fiber CV and FD were calculated from the multichannel surface EMG signal recorded from the vastus lateralis and medialis muscles. The main findings were that the two groups showed a similar rate of change of CV, whereas FD rate of change was higher in the young than in the elderly group. The trends were the same for both muscles. CV findings highlighted a non-different extent of peripheral manifestations of fatigue between groups. Nevertheless, FD rate of change was found to be steeper in the elderly than in the young, suggesting a greater increase in motor unit synchronization with ageing. These findings suggest that FD analysis could be used as a complementary variable providing further information on central mechanisms with respect to CV in fatiguing contractions.

  1. The antidepressant fluoxetine blocks the human small conductance calcium-activated potassium channels SK1, SK2 and SK3.

    PubMed

    Terstappen, Georg C; Pellacani, Annalisa; Aldegheri, Laura; Graziani, Francesca; Carignani, Corrado; Pula, Giordano; Virginio, Caterina

    2003-07-31

    The effects of fluoxetine (Prozac) on the activity of human small-conductance calcium-activated potassium (SK) channels were investigated utilizing a functional fluorescence assay with bis-(1,3-dibutylbarbituric acid)trimethine oxonol (DiBAC(4)(3)). Fluoxetine blocked SK channels stably expressed in HEK 293 cells in a concentration-dependent manner displaying half-maximal inhibitory concentrations (IC(50)) of 9 microM for hSK1, 7 microM for hSK2 and 20 microM for hSK3. The block of hSK3 channels was confirmed by whole cell patch-clamp recordings of the recombinant cells and human TE 671 cells. Fluoxetine also inhibited [(125)I]apamin binding in a concentration-dependent manner displaying IC(50) values of 63 microM for hSK1, 148 microM for hSK2 and 295 microM for hSK3. These results provide new information concerning the mechanism of therapeutic and/or side effects of one of the most widely used antidepressant drugs.

  2. Effective Energy Transfer via Plasmon-Activated High-Energy Water Promotes Its Fundamental Activities of Solubility, Ionic Conductivity, and Extraction at Room Temperature

    PubMed Central

    Yang, Chih-Ping; Chen, Hsiao-Chien; Wang, Ching-Chiung; Tsai, Po-Wei; Ho, Chia-Wen; Liu, Yu-Chuan

    2015-01-01

    Water is a ubiquitous solvent in biological, physical, and chemical processes. Unique properties of water result from water’s tetrahedral hydrogen-bonded (HB) network (THBN). The original THBN is destroyed when water is confined in a nanosized environment or localized at interfaces, resulting in corresponding changes in HB-dependent properties. In this work, we present an innovative idea to validate the reserve energy of high-energy water and applications of high-energy water to promote water’s fundamental activities of solubility, ionic conductivity, and extraction at room temperature. High-energy water with reduced HBs was created by utilizing hot electrons with energies from the decay of surface plasmon excited at gold (Au) nanoparticles (NPs). Compared to conventional deionized (DI) water, solubilities of alkali metal-chloride salts in high-energy water were significantly increased, especially for salts that release heat when dissolved. The ionic conductivity of NaCl in high-energy water was also markedly higher, especially when the electrolyte’s concentration was extremely low. In addition, antioxidative components, such as polyphenols and 2,3,5,4’-tetrahydroxystilbene-2-O-beta-d-glucoside (THSG) from teas, and Polygonum multiflorum (PM), could more effectively be extracted using high-energy water. These results demonstrate that high-energy water has emerged as a promising innovative solvent for promoting water’s fundamental activities via effective energy transfer. PMID:26658304

  3. Effective Energy Transfer via Plasmon-Activated High-Energy Water Promotes Its Fundamental Activities of Solubility, Ionic Conductivity, and Extraction at Room Temperature.

    PubMed

    Yang, Chih-Ping; Chen, Hsiao-Chien; Wang, Ching-Chiung; Tsai, Po-Wei; Ho, Chia-Wen; Liu, Yu-Chuan

    2015-01-01

    Water is a ubiquitous solvent in biological, physical, and chemical processes. Unique properties of water result from water's tetrahedral hydrogen-bonded (HB) network (THBN). The original THBN is destroyed when water is confined in a nanosized environment or localized at interfaces, resulting in corresponding changes in HB-dependent properties. In this work, we present an innovative idea to validate the reserve energy of high-energy water and applications of high-energy water to promote water's fundamental activities of solubility, ionic conductivity, and extraction at room temperature. High-energy water with reduced HBs was created by utilizing hot electrons with energies from the decay of surface plasmon excited at gold (Au) nanoparticles (NPs). Compared to conventional deionized (DI) water, solubilities of alkali metal-chloride salts in high-energy water were significantly increased, especially for salts that release heat when dissolved. The ionic conductivity of NaCl in high-energy water was also markedly higher, especially when the electrolyte's concentration was extremely low. In addition, antioxidative components, such as polyphenols and 2,3,5,4'-tetrahydroxystilbene-2-O-beta-d-glucoside (THSG) from teas, and Polygonum multiflorum (PM), could more effectively be extracted using high-energy water. These results demonstrate that high-energy water has emerged as a promising innovative solvent for promoting water's fundamental activities via effective energy transfer. PMID:26658304

  4. Effective Energy Transfer via Plasmon-Activated High-Energy Water Promotes Its Fundamental Activities of Solubility, Ionic Conductivity, and Extraction at Room Temperature

    NASA Astrophysics Data System (ADS)

    Yang, Chih-Ping; Chen, Hsiao-Chien; Wang, Ching-Chiung; Tsai, Po-Wei; Ho, Chia-Wen; Liu, Yu-Chuan

    2015-12-01

    Water is a ubiquitous solvent in biological, physical, and chemical processes. Unique properties of water result from water’s tetrahedral hydrogen-bonded (HB) network (THBN). The original THBN is destroyed when water is confined in a nanosized environment or localized at interfaces, resulting in corresponding changes in HB-dependent properties. In this work, we present an innovative idea to validate the reserve energy of high-energy water and applications of high-energy water to promote water’s fundamental activities of solubility, ionic conductivity, and extraction at room temperature. High-energy water with reduced HBs was created by utilizing hot electrons with energies from the decay of surface plasmon excited at gold (Au) nanoparticles (NPs). Compared to conventional deionized (DI) water, solubilities of alkali metal-chloride salts in high-energy water were significantly increased, especially for salts that release heat when dissolved. The ionic conductivity of NaCl in high-energy water was also markedly higher, especially when the electrolyte’s concentration was extremely low. In addition, antioxidative components, such as polyphenols and 2,3,5,4’-tetrahydroxystilbene-2-O-beta-d-glucoside (THSG) from teas, and Polygonum multiflorum (PM), could more effectively be extracted using high-energy water. These results demonstrate that high-energy water has emerged as a promising innovative solvent for promoting water’s fundamental activities via effective energy transfer.

  5. Electrodeless conductivity.

    PubMed

    Light, T S; McHale, E J; Fletcher, K S

    1989-01-01

    Electrodeless conductivity is a technique for measuring the concentration of electrolytes in solution and utilizes a probe consisting of two toroids in close proximity, both of which are immersed in the solution. In special cases, the toroids may be mounted externally on insulated pipes carrying the solution. One toroid radiates an alternating electric field in the audiofrequency range and the other acts as a receiver to pick up the small current induced by the ions moving in a conducting loop of solution. Coatings which would foul contacting electrodes, such as suspensions, precipitates or oil, have little or no effect. Applications are chiefly to continuous measurement in the chemical processing industries, including pulp and paper, mining and heavy chemical production. The principles and practical details of the method are reviewed and cell-diameter, wall, and temperature effects are discussed. PMID:18964695

  6. Knockdown of the small conductance Ca2+‐activated K+ channels is potently cytotoxic in breast cancer cell lines

    PubMed Central

    Abdulkareem, Zana Azeez; Gee, Julia MW

    2015-01-01

    Background and Purpose Small conductance calcium‐activated potassium (KCa2.x) channels have a widely accepted canonical function in regulating cellular excitability. In this study, we address a potential non‐canonical function of KCa2.x channels in breast cancer cell survival, using in vitro models. Experimental Approach The expression of all KCa2.x channel isoforms was initially probed using RT‐PCR, Western blotting and microarray analysis in five widely studied breast cancer cell lines. In order to assess the effect of pharmacological blockade and siRNA‐mediated knockdown of KCa2.x channels on these cell lines, we utilized MTS proliferation assays and also followed the corresponding expression of apoptotic markers. Key Results All of the breast cancer cell lines, regardless of their lineage or endocrine responsiveness, were highly sensitive to KCa2.x channel blockade. UCL1684 caused cytotoxicity, with LD50 values in the low nanomolar range, in all cell lines. The role of KCa2.x channels was confirmed using pharmacological inhibition and siRNA‐mediated knockdown. This reduced cell viability and also reduced expression of Bcl‐2 but increased expression of active caspase‐7 and caspase‐9. Complementary to these results, a variety of cell lines can be protected from apoptosis induced by staurosporine using the KCa2.x channel activator CyPPA. Conclusions and Implications In addition to a well‐established role for KCa2.x channels in migration, blockade of these channels was potently cytotoxic in breast cancer cell lines, pointing to modulation of KCa2.x channels as a potential therapeutic approach to breast cancer. PMID:26454020

  7. Characterisation of a cell swelling-activated K+-selective conductance of Ehrlich mouse ascites tumour cells

    PubMed Central

    Niemeyer, María Isabel; Hougaard, Charlotte; Hoffmann, Else K; Jørgensen, Finn; Stutzin, Andrés; Sepúlveda, Francisco V

    2000-01-01

    The K+ and Cl− currents activated by hypotonic cell swelling were studied in Ehrlich ascites tumour cells using the whole-cell recording mode of the patch-clamp technique. Currents were measured in the absence of added intracellular Ca2+ and with strong buffering of Ca2+. K+ current activated by cell swelling was measured as outward current at the Cl− equilibrium potential (ECl) under quasi-physiological gradients. It could be abolished by replacing extracellular Na+ with K+, thereby cancelling the driving force. Replacement with other cations suggested a selectivity sequence of K+ > Rb+ > NH4≈ Na+≈ Li+; Cs+ appeared to be inhibitory. The current-voltage relationship of the volume-sensitive K+ current was well fitted with the Goldman-Hodgkin-Katz current equation between -130 and +20 mV with a permeability coefficient of around 10−6 cm s−1 with both physiological and high-K+ extracellular solutions. The class III antiarrhythmic drug clofilium blocked the volume-sensitive K+ current in a voltage-independent manner with an IC50 of 32 μM. Clofilium was also found to be a strong inhibitor of the regulatory volume decrease response of Ehrlich cells. Cell swelling-activated K+ currents of Ehrlich cells are voltage and calcium insensitive and are resistant to a range of K+ channel inhibitors. These characteristics are similar to those of the so-called background K+ channels. Noise analysis of whole-cell current was consistent with a unitary conductance of 5.5 pS for the single channels underlying the K+ current evoked by cell swelling, measured at 0 mV under a quasi-physiological K+ gradient. PMID:10790156

  8. The Development of a Pilot Library of Cassette Tapes Dealing with Recent Advances in the Strategies and Features of Educational Research. Final Report. Including a Report of an External Project Evaluation Conducted by Jerry L. Brown, Indiana University.

    ERIC Educational Resources Information Center

    Popham, W. James

    A project was designed to develop and test a library of cassette audiotapes for improving the technical skills of educational researchers. Fourteen outstanding researchers from diverse fields were identified, and a short instructional tape was prepared by each. Subjects of the tapes included instructional objectives for intellectual skills,…

  9. Time-resolved terahertz spectroscopy of electrically conductive metal-organic frameworks doped with redox active species

    NASA Astrophysics Data System (ADS)

    Alberding, Brian G.; Heilweil, Edwin J.

    2015-09-01

    Metal-Organic Frameworks (MOFs) are three-dimensional coordination polymers that are well known for large pore surface area and their ability to adsorb molecules from both the gaseous and solution phases. In general, MOFs are electrically insulating, but promising opportunities for tuning the electronic structure exist because MOFs possess synthetic versatility; the metal and organic ligand subunits can be exchanged or dopant molecules can be introduced into the pore space. Two such MOFs with demonstrated electrical conductivity are Cu3(1,3,5-benzenetricarboxylate)2, a.k.a HKUST-1, and Cu[Ni(pyrazine-2,3-dithiolate)2]. Herein, these two MOFs have been infiltrated with the redox active species 7,7,8,8-tetracyanoquinodimethane (TCNQ) and iodine under solution phase conditions and shown to produce redox products within the MOF pore space. Vibrational bands assignable to TCNQ anion and triiodide anion have been observed in the Mid-IR and Terahertz ranges using FTIR Spectroscopy. The MOF samples have been further investigated by Time-Resolved Terehertz Spectroscopy (TRTS). Using this technique, the charge mobility, separation, and recombination dynamics have been followed on the picosecond time scale following photoexcitation with visible radiation. The preliminary results show that the MOF samples have small inherent photoconductivity with charge separation lifetimes on the order of a few picoseconds. In the case of HKUST-1, the MOF can also be supported by a TiO2 film and initial results show that charge injection into the TiO2 layer occurs with a comparable efficiency to the dye sensitizer N3, [cis-Bis(isothiocyanato)-bis(2,2'-bipyridyl-4,4'-dicarboxylato ruthenium(II)], and therefore this MOF has potential as a new light absorbing and charge conducting material in photovoltaic devices.

  10. A novel large-conductance Ca(2+)-activated potassium channel and current in nerve terminals of the rat neurohypophysis.

    PubMed Central

    Wang, G; Thorn, P; Lemos, J R

    1992-01-01

    corresponds most closely to a Ca(2+)-activated K+ current (IK(Ca)) and not to a delayed rectifier or IA-like current. It also has properties different from that of the Ca(2+)-dependent outward current described in the magnocellular neuronal cell bodies of the hypothalamus. 8. A large conductance channel is often observed in isolated rat neurohypophysial nerve terminals. The channel had a unit conductance of 231 pS in symmetrical 150 mM K+.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:1284313

  11. 30 CFR 585.600 - What plans and information must I submit to BOEM before I conduct activities on my lease or grant?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... must submit a SAP, COP, or GAP and receive BOEM approval as set forth in the following table: Before... approval for your SAP according to §§ 585.605 through 585.613. (b) conduct any activities pertaining...

  12. 30 CFR 585.600 - What plans and information must I submit to BOEM before I conduct activities on my lease or grant?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... must submit a SAP, COP, or GAP and receive BOEM approval as set forth in the following table: Before... your COP, according to §§ 585.620 through 585.629. (c) conduct any activities on your limited...

  13. 30 CFR 585.600 - What plans and information must I submit to BOEM before I conduct activities on my lease or grant?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... must submit a SAP, COP, or GAP and receive BOEM approval as set forth in the following table: Before... your COP, according to §§ 585.620 through 585.629. (c) conduct any activities on your limited...

  14. The voltage-activated hydrogen ion conductance in rat alveolar epithelial cells is determined by the pH gradient

    PubMed Central

    1995-01-01

    Voltage-activated H+ currents were studied in rat alveolar epithelial cells using tight-seal whole-cell voltage clamp recording and highly buffered, EGTA-containing solutions. Under these conditions, the tail current reversal potential, Vrev, was close to the Nernst potential, EH, varying 52 mV/U pH over four delta pH units (delta pH = pHo - pHi). This result indicates that H+ channels are extremely selective, PH/PTMA > 10(7), and that both internal and external pH, pHi, and pHo, were well controlled. The H+ current amplitude was practically constant at any fixed delta pH, in spite of up to 100-fold symmetrical changes in H+ concentration. Thus, the rate-limiting step in H+ permeation is pH independent, must be localized to the channel (entry, permeation, or exit), and is not bulk diffusion limitation. The instantaneous current- voltage relationship exhibited distinct outward rectification at symmetrical pH, suggesting asymmetry in the permeation pathway. Sigmoid activation kinetics and biexponential decay of tail currents near threshold potentials indicate that H+ channels pass through at least two closed states before opening. The steady state H+ conductance, gH, as well as activation and deactivation kinetic parameters were all shifted along the voltage axis by approximately 40 mV/U pH by changes in pHi or pHo, with the exception of the fast component of tail currents which was shifted less if at all. The threshold potential at which H+ currents were detectably activated can be described empirically as approximately 20-40(pHo-pHi) mV. If internal and external protons regulate the voltage dependence of gH gating at separate sites, then they must be equally effective. A simpler interpretation is that gating is controlled by the pH gradient, delta pH. We propose a simple general model to account for the observed delta pH dependence. Protonation at an externally accessible site stabilizes the closed channel conformation. Deprotonation of this site permits a

  15. Verrucous carcinomas of the head and neck, including those with associated squamous cell carcinoma, lack transcriptionally active high-risk human papillomavirus.

    PubMed

    Patel, Kalyani R; Chernock, Rebecca D; Zhang, Tian R; Wang, Xiaowei; El-Mofty, Samir K; Lewis, James S

    2013-11-01

    Most oropharyngeal squamous cell carcinomas (SCC) and histologic variants harbor transcriptionally active human papillomavirus (HPV). While HPV DNA can be found in many non-oropharyngeal head and neck carcinomas, transcriptionally active HPV is rare. Verrucous carcinoma is a variant with bland cytology, warty appearance, locally destructive growth, and lack of metastasis when lacking a frankly invasive carcinoma component. Studies have shown variable rates of HPV DNA and p16 protein expression in such tumors but still have not clearly addressed if the virus has biological activity or clinical relevance in the positive cases. Department files were searched for verrucous neoplasms, including pure verrucous carcinoma, verrucous carcinoma with dysplasia or minimal invasion, and SCC arising in verrucous carcinoma (ie, having a major component of frankly invasive carcinoma). p16 immunohistochemistry, HPV DNA polymerase chain reaction (PCR) and E6/E7 mRNA reverse transcription PCR for high-risk HPV types were performed. Of the 49 cases, 6 (12.2%) showed strong (>50%) staining for p16. HPV DNA was detected in 7/49 (14.3%) cases, but only one case was positive for both p16, and HPV DNA. A total of 36 cases yielded sufficient RNA for RT-PCR (18 verrucous carcinomas, 13 atypical verrucous carcinomas, and 5 SCC arising in verrucous carcinoma). All 36 were negative, including the four p16-positive and three HPV DNA-positive tumors tested. Although a minority of verrucous carcinoma lesions are p16 and HPV DNA positive, transcriptionally active high-risk HPV is uniformly absent. These findings argue that verrucous carcinoma and its related squamous cell carcinomas are not HPV-driven tumors.

  16. Conductive Polymers

    SciTech Connect

    Bohnert, G.W.

    2002-11-22

    Electroluminescent devices such as light-emitting diodes (LED) and high-energy density batteries. These new polymers offer cost savings, weight reduction, ease of processing, and inherent rugged design compared to conventional semiconductor materials. The photovoltaic industry has grown more than 30% during the past three years. Lightweight, flexible solar modules are being used by the U.S. Army and Marine Corps for field power units. LEDs historically used for indicator lights are now being investigated for general lighting to replace fluorescent and incandescent lights. These so-called solid-state lights are becoming more prevalent across the country since they produce efficient lighting with little heat generation. Conductive polymers are being sought for battery development as well. Considerable weight savings over conventional cathode materials used in secondary storage batteries make portable devices easier to carry and electric cars more efficient and nimble. Secondary battery sales represent an $8 billion industry annually. The purpose of the project was to synthesize and characterize conductive polymers. TRACE Photonics Inc. has researched critical issues which affect conductivity. Much of their work has focused on production of substituted poly(phenylenevinylene) compounds. These compounds exhibit greater solubility over the parent polyphenylenevinylene, making them easier to process. Alkoxy substituted groups evaluated during this study included: methoxy, propoxy, and heptyloxy. Synthesis routes for production of alkoxy-substituted poly phenylenevinylene were developed. Considerable emphasis was placed on final product yield and purity.

  17. Small-conductance Ca(2+)-activated K(+) channels: Heterogeneous affinity in rat brain structures and cognitive modulation by specific blockers.

    PubMed

    Mpari, Bedel; Sreng, Leam; Regaya, Imed; Mourre, Christiane

    2008-07-28

    Small-conductance calcium-activated potassium channels (K(Ca)2) generating the medium afterhyperpolarization seen after an action potential modulate the neuronal integration signal. The effects of two K(Ca)2 channel blockers, apamin, specific to K(Ca)2.2 and K(Ca)2.3 channels, and lei-Dab7, which binds to K(Ca)2.2 channels only, were compared to evaluate the involvement of K(Ca)2 channel subunits in behavior, spatial learning and memory in rats. Intracerebroventricular (9-5 ng) injections of lei-dab7 decreased locomotor activity, food intake and body weight in rats deprived of food. A dose of 3 ng lei-Dab7 had no effect on these types of behavior. We therefore used this dose for attention and memory tasks. No modification to attention or memory was observed in a spatial radial-arm maze task with rats given 3 ng lei-Dab7, whereas apamin (0.3 ng) improved reference memory and accelerated changes of strategy from egocentric to allocentric. These findings suggest that K(Ca)2.3 blockade improves memory in rats. Lei-Dab7 entirely outcompeted the binding of iodinated apamin to 64 brain structures (mean IC(50): 34.5 nM), although IC(50) values were highly variable. By contrast, overall IC(50) values for apamin were close to mean values (11.3 pM). The very low affinity of the hippocampus and neocortex for lei-Dab7 may account for the absence of a behavioral effect of this compound. The variability of IC(50) values suggests that K(Ca)2 channel composition varies considerably as a function of the brain structure considered. PMID:18561910

  18. Antisense oligodeoxynucleotides to the cystic fibrosis transmembrane conductance regulator inhibit cAMP-activated but not calcium-activated chloride currents.

    PubMed Central

    Wagner, J A; McDonald, T V; Nghiem, P T; Lowe, A W; Schulman, H; Gruenert, D C; Stryer, L; Gardner, P

    1992-01-01

    Phosphorylation of the cystic fibrosis transmembrane conductance regulator (CFTR) by cAMP-dependent protein kinase leads to chloride flux in epithelial cells. Is CFTR also required for the calcium-dependent activation of chloride channels? We used antisense oligodeoxynucleotides to CFTR to reduce the expression of CFTR in colonic and tracheal epithelial cells. The antisense oligomers were a pair of adjacent 18-mers complementary to nucleotides 1-18 and 19-36 of CFTR mRNA. Sense and misantisense oligomers served as controls. A 48-h antisense treatment reduced the expression of CFTR protein as assayed by immunoprecipitation and autoradiography to 26% of the level in sense-treated T84 cells. Whole-cell patch clamp revealed that a 48-h antisense treatment of T84 and 56FHTE-8o- fetal tracheal epithelial cells reduced the cAMP-activated chloride current to approximately 10% of that in sense-treated cells. The half-life of functional CFTR is less than 24 h in these cells. In contrast, the calcium-activated chloride current was not affected by antisense treatment. Hence, the cAMP and calcium pathways are separate. CFTR is required for the cAMP pathway but not for the calcium pathway. Images PMID:1379720

  19. Optical modulator including grapene

    DOEpatents

    Liu, Ming; Yin, Xiaobo; Zhang, Xiang

    2016-06-07

    The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

  20. KCNN Genes that Encode Small-Conductance Ca2+-Activated K+ Channels Influence Alcohol and Drug Addiction.

    PubMed

    Padula, Audrey E; Griffin, William C; Lopez, Marcelo F; Nimitvilai, Sudarat; Cannady, Reginald; McGuier, Natalie S; Chesler, Elissa J; Miles, Michael F; Williams, Robert W; Randall, Patrick K; Woodward, John J; Becker, Howard C; Mulholland, Patrick J

    2015-07-01

    Small-conductance Ca(2+)-activated K(+) (KCa2) channels control neuronal excitability and synaptic plasticity, and have been implicated in substance abuse. However, it is unknown if genes that encode KCa2 channels (KCNN1-3) influence alcohol and drug addiction. In the present study, an integrative functional genomics approach shows that genetic datasets for alcohol, nicotine, and illicit drugs contain the family of KCNN genes. Alcohol preference and dependence QTLs contain KCNN2 and KCNN3, and Kcnn3 transcript levels in the nucleus accumbens (NAc) of genetically diverse BXD strains of mice predicted voluntary alcohol consumption. Transcript levels of Kcnn3 in the NAc negatively correlated with alcohol intake levels in BXD strains, and alcohol dependence enhanced the strength of this association. Microinjections of the KCa2 channel inhibitor apamin into the NAc increased alcohol intake in control C57BL/6J mice, while spontaneous seizures developed in alcohol-dependent mice following apamin injection. Consistent with this finding, alcohol dependence enhanced the intrinsic excitability of medium spiny neurons in the NAc core and reduced the function and protein expression of KCa2 channels in the NAc. Altogether, these data implicate the family of KCNN genes in alcohol, nicotine, and drug addiction, and identify KCNN3 as a mediator of voluntary and excessive alcohol consumption. KCa2.3 channels represent a promising novel target in the pharmacogenetic treatment of alcohol and drug addiction.

  1. Characterization Activities Conducted at the 183-DR Site in Support of an In Situ Gaseous Reduction Demonstration

    SciTech Connect

    Thornton, Edward C.; Gilmore, Tyler J.; Olsen, Khris B.; Schalla, Ronald; Cantrell, Kirk J.

    2001-03-30

    In Situ Gaseous Reduction (ISGR) is a technology developed by DOE for the remediation of soil waste sites contaminated with hexavalent chromium. This document presents information associated with characterization activities conducted at the 183-DR site at Hanford, which is associated with a significant groundwater contaminant plume and was formerly a water treatment facility that utilized chromate as a corrosion inhibitor. Geotechnical and chemical data were collected during the excavation of trenches and the drilling of two vadose zone boreholes to support a possible ISGR demonstration at 183-DR. Although elevated total chromium and trace levels of hexavalent chromium were identified from one of the trenches and one of the boreholes, it appears that the boreholes missed the vadose zone contaminant source responsible for the chromium groundwater plume located downgradient of the 183-DR site. Recommendations are provided, however, for future work at 183-DR that may serve to identify the source for the groundwater plume and possibly provide an opportunity for an ISGR demonstration.

  2. Transparent and electrically conductive GaSb/Si direct wafer bonding at low temperatures by argon-beam surface activation

    NASA Astrophysics Data System (ADS)

    Predan, F.; Reinwand, D.; Klinger, V.; Dimroth, F.

    2015-10-01

    Direct wafer bonds of the material system n-GaSb/n-Si have been achieved by means of a low-temperature direct wafer bonding process, enabling an optical transparency of the bonds along with a high electrical conductivity of the boundary layer. In the used technique, the surfaces are activated by sputter-etching with an argon fast-atom-beam (FAB) and bonded in ultra-high vacuum. The bonds were annealed at temperatures between 300 and 400 °C, followed by an optical, mechanical and electrical characterization of the interface. Additionally, the influence of the sputtering on the surface topography of the GaSb was explicitly investigated. Fully bonded wafer pairs with high bonding strengths were found, as no blade could be inserted into the bonds without destroying the samples. The interfacial resistivities of the bonded wafers were significantly reduced by optimizing the process parameters, by which Ohmic interfacial resistivities of less than 5 mΩ cm2 were reached reproducibly. These promising results make the monolithic integration of GaSb on Si attractive for various applications.

  3. KCNN Genes that Encode Small-Conductance Ca2+-Activated K+ Channels Influence Alcohol and Drug Addiction

    PubMed Central

    Padula, Audrey E; Griffin, William C; Lopez, Marcelo F; Nimitvilai, Sudarat; Cannady, Reginald; McGuier, Natalie S; Chesler, Elissa J; Miles, Michael F; Williams, Robert W; Randall, Patrick K; Woodward, John J; Becker, Howard C; Mulholland, Patrick J

    2015-01-01

    Small-conductance Ca2+-activated K+ (KCa2) channels control neuronal excitability and synaptic plasticity, and have been implicated in substance abuse. However, it is unknown if genes that encode KCa2 channels (KCNN1-3) influence alcohol and drug addiction. In the present study, an integrative functional genomics approach shows that genetic datasets for alcohol, nicotine, and illicit drugs contain the family of KCNN genes. Alcohol preference and dependence QTLs contain KCNN2 and KCNN3, and Kcnn3 transcript levels in the nucleus accumbens (NAc) of genetically diverse BXD strains of mice predicted voluntary alcohol consumption. Transcript levels of Kcnn3 in the NAc negatively correlated with alcohol intake levels in BXD strains, and alcohol dependence enhanced the strength of this association. Microinjections of the KCa2 channel inhibitor apamin into the NAc increased alcohol intake in control C57BL/6J mice, while spontaneous seizures developed in alcohol-dependent mice following apamin injection. Consistent with this finding, alcohol dependence enhanced the intrinsic excitability of medium spiny neurons in the NAc core and reduced the function and protein expression of KCa2 channels in the NAc. Altogether, these data implicate the family of KCNN genes in alcohol, nicotine, and drug addiction, and identify KCNN3 as a mediator of voluntary and excessive alcohol consumption. KCa2.3 channels represent a promising novel target in the pharmacogenetic treatment of alcohol and drug addiction. PMID:25662840

  4. Activity of a long-acting echinocandin, CD101, determined using CLSI and EUCAST reference methods, against Candida and Aspergillus spp., including echinocandin- and azole-resistant isolates

    PubMed Central

    Pfaller, Michael A.; Messer, Shawn A.; Rhomberg, Paul R.; Jones, Ronald N.; Castanheira, Mariana

    2016-01-01

    Objectives The objective of this study was to evaluate the in vitro activity of CD101, a novel echinocandin with a long serum elimination half-life, and comparator (anidulafungin and caspofungin) antifungal agents against a collection of Candida and Aspergillus spp. isolates. Methods CD101 and comparator agents were tested against 106 Candida spp. and 67 Aspergillus spp. isolates, including 27 isolates of Candida harbouring fks hotspot mutations and 12 itraconazole non-WT Aspergillus, using CLSI and EUCAST reference susceptibility broth microdilution (BMD) methods. Results Against WT and fks mutant Candida albicans, Candida glabrata and Candida tropicalis, the activity of CD101 [MIC90 = 0.06, 0.12 and 0.03 mg/L, respectively (CLSI method values)] was comparable to that of anidulafungin (MIC90 = 0.03, 0.12 and 0.03 mg/L, respectively) and caspofungin (MIC90 = 0.12, 0.25 and 0.12 mg/L, respectively). WT Candida krusei isolates were very susceptible to CD101 (MIC = 0.06 mg/L). CD101 activity (MIC50/90 = 1/2 mg/L) was comparable to that of anidulafungin (MIC50/90 = 2/2 mg/L) against Candida parapsilosis. CD101 (MIC mode = 0.06 mg/L for C. glabrata) was 2- to 4-fold more active against fks hotspot mutants than caspofungin (MIC mode = 0.5 mg/L). CD101 was active against Aspergillus fumigatus, Aspergillus terreus, Aspergillus niger and Aspergillus flavus (MEC90 range = ≤0.008–0.03 mg/L). The essential agreement between CLSI and EUCAST methods for CD101 was 92.0%–100.0% among Candida spp. and 95.0%–100.0% among Aspergillus spp. Conclusions The activity of CD101 is comparable to that of other members of the echinocandin class for the prevention and treatment of serious fungal infections. Similar results for CD101 activity versus Candida and Aspergillus spp. may be obtained with either CLSI or EUCAST BMD methods. PMID:27287236

  5. Time use differences in activity participation among children 4-5 years old with and without the risk of developing conduct problems.

    PubMed

    Yu, Mong-Lin; Ziviani, Jenny; Baxter, Janeen; Haynes, Michele

    2012-01-01

    Conduct problems in childhood are associated with the way in which children engage in daily activities. Research, to date, on conduct problems in relation to time use has primarily focused on school aged children and their participation in discrete activities such as watching TV and sport. The purpose of the present study is to determine if children at risk of developing conduct problems have different activity patterns compared to those not at risk. Specifically aspects of time use which concern involvement in activities that provide physical exertion, structure, rest and social engagement were examined. Data for this investigation were drawn from the Longitudinal Study of Australian Children (Wave 1) and focused on 4936 children aged 4-5 years. Findings indicate that children at risk of developing conduct problems spend significantly more time in: physical activities such as "riding a bike", and "in the company of adults only" than children not at risk of developing conduct problems but less time "with peers under adult supervision". Gender differences were also found in the same activities with boys participating in more "bike riding" and activities "without peers under adult supervision" than girls. Young children generally participated in more physical activities and spend more time "with peers while supervised by adults" on weekend days, and more time in "structured activities" and "in the company of adults only" on weekdays. These findings are discussed in respect of the potentially risky nature of physical activity choice and the contribution of adult supervision in the context of peer group participation for children at risk of developing conduct problems.

  6. Activation of muscarinic M3 receptors inhibits large-conductance voltage- and Ca2+-activated K+ channels in rat urinary bladder smooth muscle cells

    PubMed Central

    Parajuli, Shankar P.

    2013-01-01

    Large conductance voltage- and Ca2+-activated K+ (BK) channels are key regulators of detrusor smooth muscle (DSM) contraction and relaxation during urine voiding and storage. Here, we explored whether BK channels are regulated by muscarinic receptors (M-Rs) in native freshly isolated rat DSM cells under physiological conditions using the perforated whole cell patch-clamp technique and pharmacological inhibitors. M-R activation with carbachol (1 μM) initially evoked large transient outward BK currents, followed by inhibition of the spontaneous transient outward BK currents (STBKCs) in DSM cells. Carbachol (1 μM) also inhibited the amplitude and frequency of spontaneous transient hyperpolarizations (STHs) and depolarized the DSM cell membrane potential. Selective inhibition of the muscarinic M3 receptors (M3-Rs) with 4-diphenylacetoxy-N-methylpiperidine (4-DAMP; 0.1 μM), but not muscarinic M2 receptors with methoctramine (1 μM), blocked the carbachol inhibitory effects on STBKCs. Furthermore, blocking the inositol 1,4,5-triphosphate (IP3) receptors with xestospongin-C (1 μM) inhibited the carbachol-induced large transient outward BK currents without affecting carbachol inhibitory effects on STBKCs. Upon pharmacological inhibition of all known cellular sources of Ca2+ for BK channel activation, carbachol (1 μM) did not affect the voltage-step-induced steady-state BK currents, suggesting that the muscarinic effects in DSM cells are mediated by mobilization of intracellular Ca2+. In conclusion, our findings provide strong evidence that activation of M3-Rs leads to inhibition of the STBKCs, STHs, and depolarization of DSM cells. Collectively, the data suggest the existence of functional interactions between BK channels and M3-Rs at a cellular level in DSM. PMID:23703523

  7. Measuring Changes in Electrical Conductivity of Fractures from DC Resistivity Data in an Active Oilfield Environment: A Model Study for Surface-Based Data.

    NASA Astrophysics Data System (ADS)

    Weiss, C. J.; Aldridge, D. F.; Knox, H. A.; Schramm, K. A.; Bartel, L. C.

    2015-12-01

    Presented here are preliminary results of a numerical modeling study on the feasibility of using DC resistivity data to make useful inferences on depth, size and orientation of subsurface fracture systems in an active oilfield environment. Specifically, we consider an experiment where the steel-cased borehole (consisting of a shallow, vertical section and deep, horizontal section) is one electrode of the DC source, with the other source electrode grounded at the Air/Earth interface some distance away. For simplicity, the fractures are modeled as short sequence of vertical sheets intersecting the horizontal section of the well casing. Finite element analysis of this system shows that as fracture conductivity is elevated, two effects (at least) are observed: a local perturbation in the electric potential in the vicinity of the fracture set, with limited far-field expression; and, an overall change in the electric potential of the entire borehole casing due to current leakage at the site of the fractures. Under ideal conditions, our results suggest that far-field, time-lapse measurements of DC potentials surrounding a borehole casing can be reliably interpreted by simple, linear inversion for a Coulomb charge distribution along the borehole path, including a local charge perturbation due to the fractures. In contrast to regularized, nonlinear 3D inversion of broadband EM or DC data, this approach offers an inexpensive method for detecting and monitoring the time-evolution of electrically conducting fractures while ultimately providing an estimate of their effective conductivity - the latter providing an important measure independent of seismic methods on fracture shape, size, and hydraulic connectivity.

  8. Stages of change for physical activity and dietary habits in persons with type 2 diabetes included in a mobile health intervention: the Norwegian study in RENEWING HEALTH

    PubMed Central

    Holmen, Heidi; Wahl, Astrid; Torbjørnsen, Astrid; Jenum, Anne Karen; Småstuen, Milada Cvancarova; Ribu, Lis

    2016-01-01

    Objective The aim of this study was to investigate stages of change for physical activity and dietary habits using baseline data from persons with type 2 diabetes included in a mobile health intervention. We examined the associations between stages of change for physical activity change and dietary change, and between stages of change for each behavior and individual characteristics, health-related quality of life, self-management, depressive symptoms, and lifestyle. Research design and methods We examined 151 persons with type 2 diabetes with an glycated hemoglobin (HbA1c) level ≥7.1%, aged ≥18 years at baseline of a randomized controlled trial, before testing a mobile app with or without health counseling. Stages of change were dichotomized into ‘pre-action’ and ‘action’. Self-management was measured using the Health Education Impact Questionnaire (heiQ) where a higher score reflects increased self-management, and health-related quality of life was measured with the Short-Form-36 (SF-36). Logistic regression modeling was performed. Results The median HbA1c level was 7.9% (7.1–12.4), 90% were overweight or obese, and 20% had ≥3 comorbidities. 58% were in the preaction stage for physical activity change and 79% in the preaction stage for dietary change. Higher scores of self-management were associated with an increased chance of being in the action stage for both dietary change and physical activity change. Higher body mass index was associated with an 8% reduced chance of being in the action stage for physical activity change (OR 0.92, 95% CI 0.86 to 0.99). Conclusions Being in the action stage was associated with higher scores of self-management, crucial for type 2 diabetes. Over half of the participants were in the preaction stage for physical activity and dietary change, and many had a high disease burden with comorbidities and overweight. Trial registration number NCT01315756. PMID:27239317

  9. A Comparison of Brunt Criteria, the Non Alcoholic Fatty Liver Disease Activity Score (NAS) & a Proposed NAS-including fibrosis as Valid Diagnostic Scores for NASH

    PubMed Central

    Santiago-Rolón, Amarilys; Purcell, Dagmary; Rosado, Kathia; Toro, Doris H.

    2016-01-01

    Objective Non-alcoholic steatohepatitis (NASH) can result in cirrhosis and end stage liver disease. It is of utmost importance to differentiate NASH from simple steatosis. The aim of this study is to determine the prevalence of NASH in Latino veterans with metabolic syndrome and compare histologic grading using Brunt Criteria, the NAFLD activity score (NAS), and a proposed NAS score including fibrosis. Methods Veterans with metabolic syndrome, hepatic steatosis and elevation of ALT/AST who underwent a liver biopsy from 2004-2010 were included in this study. Biopsies were evaluated by a single blinded Hepatopathologist. Steatosis, lobular inflammation, ballooning and fibrosis were graded per specimen. Each biopsy was evaluated using Brunt criteria, NAS and NAS plus fibrosis. Results Sixty patients were included in this study, 88.3% men with a mean age of 50.4 (± 12.8). 50.0% met criteria for NASH according to the Brunt system. When classifying biopsies using NAS, only 30.0% (18/60) had a score ≥5, while when adding fibrosis, the number of patients with a score ≥5 increased to 33 (55.0%). When evaluating the predictive ability of the two scoring systems, we found that NAS including fibrosis had a higher sensitivity than NAS (86.7% vs. 40.0%) and a lower specificity (76.7% vs. 80.0%). Conclusion In our population with metabolic syndrome and altered liver function tests, about 50-55% had steatohepatitis. There were significant differences between the scoring systems. When using NAS-plus-fibrosis more patients were recognized and the sensitivity increased. Further validation studies are required to evaluate this proposed NAS scoring System. PMID:26602577

  10. Increased Expression of the Large Conductance, Calcium-Activated K+ (BK) Channel in Adult-Onset Neuronal Ceroid Lipofuscinosis

    PubMed Central

    Donnelier, Julien; Braun, Samuel T.; Dolzhanskaya, Natalia; Ahrendt, Eva; Braun, Andrew P.; Velinov, Milen; Braun, Janice E. A.

    2015-01-01

    Cysteine string protein (CSPα) is a presynaptic J protein co-chaperone that opposes neurodegeneration. Mutations in CSPα (i.e., Leu115 to Arg substitution or deletion (Δ) of Leu116) cause adult neuronal ceroid lipofuscinosis (ANCL), a dominantly inherited neurodegenerative disease. We have previously demonstrated that CSPα limits the expression of large conductance, calcium-activated K+ (BK) channels in neurons, which may impact synaptic excitability and neurotransmission. Here we show by western blot analysis that expression of the pore-forming BKα subunit is elevated ~2.5 fold in the post-mortem cortex of a 36-year-old patient with the Leu116∆ CSPα mutation. Moreover, we find that the increase in BKα subunit level is selective for ANCL and not a general feature of neurodegenerative conditions. While reduced levels of CSPα are found in some postmortem cortex specimens from Alzheimer’s disease patients, we find no concomitant increase in BKα subunit expression in Alzheimer’s specimens. Both CSPα monomer and oligomer expression are reduced in synaptosomes prepared from ANCL cortex compared with control. In a cultured neuronal cell model, CSPα oligomers are short lived. The results of this study indicate that the Leu116∆ mutation leads to elevated BKα subunit levels in human cortex and extend our initial work in rodent models demonstrating the modulation of BKα subunit levels by the same CSPα mutation. While the precise sequence of pathogenic events still remains to be elucidated, our findings suggest that dysregulation of BK channels may contribute to neurodegeneration in ANCL. PMID:25905915

  11. An amino acid outside the pore region influences apamin sensitivity in small conductance Ca2+-activated K+ channels.

    PubMed

    Nolting, Andreas; Ferraro, Teresa; D'hoedt, Dieter; Stocker, Martin

    2007-02-01

    Small conductance calcium-activated potassium channels (SK, K(Ca)) are a family of voltage-independent K+ channels with a distinct physiology and pharmacology. The bee venom toxin apamin inhibits exclusively the three cloned SK channel subtypes (SK1, SK2, and SK3) with different affinity, highest for SK2, lowest for SK1, and intermediate for SK3 channels. The high selectivity of apamin made it a valuable tool to study the molecular makeup and function of native SK channels. Three amino acids located in the outer vestibule of the pore are of particular importance for the different apamin sensitivities of SK channels. Chimeric SK1 channels, enabling the homomeric expression of the rat SK1 (rSK1) subunit and containing the core domain (S1-S6) of rSK1, are apamin-insensitive. By contrast, channels formed by the human orthologue human SK1 (hSK1) are sensitive to apamin. This finding hinted at the involvement of regions beyond the pore as determinants of apamin sensitivity, because hSK1 and rSK1 have an identical amino acid sequence in the pore region. Here we investigated which parts of the channels outside the pore region are important for apamin sensitivity by constructing chimeras between apamin-insensitive and -sensitive SK channel subunits and by introducing point mutations. We demonstrate that a single amino acid situated in the extracellular loop between the transmembrane segments S3 and S4 has a major impact on apamin sensitivity. Our findings enabled us to convert the hSK1 channel into a channel that was as sensitive for apamin as SK2, the SK channel with the highest sensitivity.

  12. Palmitoylation of the β4-subunit regulates surface expression of large conductance calcium-activated potassium channel splice variants.

    PubMed

    Chen, Lie; Bi, Danlei; Tian, Lijun; McClafferty, Heather; Steeb, Franziska; Ruth, Peter; Knaus, Hans Guenther; Shipston, Michael J

    2013-05-01

    Regulatory β-subunits of large conductance calcium- and voltage-activated potassium (BK) channels play an important role in generating functional diversity and control of cell surface expression of the pore forming α-subunits. However, in contrast to α-subunits, the role of reversible post-translational modification of intracellular residues on β-subunit function is largely unknown. Here we demonstrate that the human β4-subunit is S-acylated (palmitoylated) on a juxtamembrane cysteine residue (Cys-193) in the intracellular C terminus of the regulatory β-subunit. β4-Subunit palmitoylation is important for cell surface expression and endoplasmic reticulum (ER) exit of the β4-subunit alone. Importantly, palmitoylated β4-subunits promote the ER exit and surface expression of the pore-forming α-subunit, whereas β4-subunits that cannot be palmitoylated do not increase ER exit or surface expression of α-subunits. Strikingly, however, this palmitoylation- and β4-dependent enhancement of α-subunit surface expression was only observed in α-subunits that contain a putative trafficking motif (… REVEDEC) at the very C terminus of the α-subunit. Engineering this trafficking motif to other C-terminal α-subunit splice variants results in α-subunits with reduced surface expression that can be rescued by palmitoylated, but not depalmitoylated, β4-subunits. Our data reveal a novel mechanism by which palmitoylated β4-subunit controls surface expression of BK channels through masking of a trafficking motif in the C terminus of the α-subunit. As palmitoylation is dynamic, this mechanism would allow precise control of specific splice variants to the cell surface. Our data provide new insights into how complex interplay between the repertoire of post-transcriptional and post-translational mechanisms controls cell surface expression of BK channels.

  13. Altered expression and function of small-conductance (SK) Ca2+-activated K+ channels in pilocarpine-treated epileptic rats

    PubMed Central

    Oliveira, Mauro S.; Skinner, Frank; Arshadmansab, Massoud F.; Garcia, Ileana; Mello, Carlos F.; Knaus, Hans-Günther; Ermolinsky, Boris S.; Pacheco Otalora, Luis F.; Garrido-Sanabria, Emilio R.

    2010-01-01

    Small conductance calcium (Ca2+) activated SK channels are critical regulators of neuronal excitability in hippocampus. Accordingly, these channels are thought to play a key role in controlling neuronal activity in acute models of epilepsy. In this study, we investigate the expression and function of SK channels in the pilocarpine model of mesial temporal lobe epilepsy. For this purpose, protein expression was assessed using western blotting assays and gene expression was analyzed using TaqMan-based probes and the quantitative real-time polymerase chain reaction (qPCR) comparative method delta-delta cycle threshold (ΔΔCT) in samples extracted from control and epileptic rats. In addition, the effect of SK channel antagonist UCL1684 and agonist NS309 on CA1 evoked population spikes was studied in hippocampal slices. Western blotting analysis showed a significant reduction in the expression of SK1 and SK2 channels at 10 days following status epilepticus (SE), but levels recovered at 1 month and at more than 2 months after SE. In contrast, a significant down-regulation of SK3 channels was detected after 10 days of SE. Analysis of gene expression by qPCR revealed a significant reduction of transcripts for SK2 (Kcnn1) and SK3 (Kcnn3) channels as early as 10 days following pilocarpine-induced SE and during the chronic phase of the pilocarpine model. Moreover, bath application of UCL1684 (100 nM for 15 min) induced a significant increase of the population spike amplitude and number of spikes in the hippocampal CA1 area of slices obtained control and chronic epileptic rats. This effect was obliterated by co-administration of UCL1684 with SK channel agonist NS309 (1 μM). Application of NS309 failed to modify population spikes in the CA1 area of slices taken from control and epileptic rats. These data indicate an abnormal expression of SK channels and a possible dysfunction of these channels in experimental MTLE. PMID:20553876

  14. Development of GoSlo-SR-5-69, a potent activator of large conductance Ca2+-activated K+ (BK) channels.

    PubMed

    Roy, Subhrangsu; Large, Roddy J; Akande, Adebola Morayo; Kshatri, Aravind; Webb, Tim I; Domene, Carmen; Sergeant, Gerard P; McHale, Noel G; Thornbury, Keith D; Hollywood, Mark A

    2014-03-21

    We have designed, synthesised and characterised the effects of a number of novel anthraquinone derivatives and assessed their effects on large conductance, Ca(2+) activated K(+) (BK) channels recorded from rabbit bladder smooth muscle cells using the excised, inside/out configuration of the patch clamp technique. These compounds are members of the GoSlo-SR family of compounds, which potently open BK channels and shift the voltage required for half maximal activation (V1/2) negatively. The efficacy of the anilinoanthraquinone derivatives was enhanced when the size of ring D was increased, since the cyclopentane and cyclohexane derivatives shifted the V1/2, by -24 ± 6 mV and -54 ± 8 mV, respectively, whereas the cycloheptane and cyclooctane derivatives shifted the V1/2 by -61 ± 6 mV and -106 ± 6 mV. To examine if a combination of hydrophobicity and steric bulking of this region further enhanced their ability to open BK channels, we synthesised a number of naphthalene and tetrahydro-naphthalene derivatives. The tetrahydro-2-naphthalene derivative GoSlo-SR-5-69 was the most potent and efficacious of the series since it was able to shift the activation V1/2 by greater than -100 mV when applied at a concentration of 1 μM and had an EC50 of 251 nM, making it one of the most potent and efficacious BK channel openers synthesised to date. PMID:24561672

  15. PREFACE: 9th International Fröhlich's Symposium: Electrodynamic Activity of Living Cells (Including Microtubule Coherent Modes and Cancer Cell Physics)

    NASA Astrophysics Data System (ADS)

    Cifra, Michal; Pokorný, Jirí; Kucera, Ondrej

    2011-12-01

    This volume contains papers presented at the International Fröhlich's Symposium entitled 'Electrodynamic Activity of Living Cells' (1-3 July 2011, Prague, Czech Republic). The Symposium was the 9th meeting devoted to physical processes in living matter organized in Prague since 1987. The hypothesis of oscillation systems in living cells featured by non-linear interaction between elastic and electrical polarization fields, non-linear interactions between the system and the heat bath leading to energy downconversion along the frequency scale, energy condensation in the lowest frequency mode and creation of a coherent state was formulated by H Fröhlich, founder of the theory of dielectric materials. He assumed that biological activity is based not only on biochemical but also on biophysical mechanisms and that their disturbances form basic links along the cancer transformation pathway. Fröhlich outlined general ideas of non-linear physical processes in biological systems. The downconversion and the elastic-polarization interactions should be connected in a unified theory and the solution based on comprehensive non-linear characteristics. Biochemical and genetic research of biological systems are highly developed and have disclosed a variety of cellular and subcellular structures, chemical reactions, molecular information transfer, and genetic code sequences - including their pathological development. Nevertheless, the cancer problem is still a big challenge. Warburg's discovery of suppressed oxidative metabolism in mitochondria in cancer cells suggested the essential role of physical mechanisms (but his discovery has remained without impact on cancer research and on the study of physical properties of biological systems for a long time). Mitochondria, the power plants of the cell, have several areas of activity-oxidative energy production is connected with the formation of a strong static electric field around them, water ordering, and liberation of non

  16. Effect of mechanical activation on thermal and electrical conductivity of sintered Cu, Cr, and Cu/Cr composite powders

    NASA Astrophysics Data System (ADS)

    Rogachev, A. S.; Kuskov, K. V.; Moskovskikh, D. O.; Usenko, A. A.; Orlov, A. O.; Shkodich, N. F.; Alymov, M. I.; Mukasyan, A. S.

    2016-06-01

    The results of measurement of electric resistivity and thermal conductivity of materials obtained by spark plasma sintering from powders of Cu, Cr, and their mixtures in the range of 300-600 K are presented. It is shown that the grinding of powders in planetary mills results in a reasonably substantial change in the electric and thermal properties of materials: to increasing electric resistivity and decreasing thermal conductivity and temperature coefficients of electric resistivity. The possible causes of these effects are considered.

  17. Overexpression of the Large-Conductance, Ca2+-Activated K+ (BK) Channel Shortens Action Potential Duration in HL-1 Cardiomyocytes

    PubMed Central

    Stimers, Joseph R.; Song, Li; Rusch, Nancy J.; Rhee, Sung W.

    2015-01-01

    Long QT syndrome is characterized by a prolongation of the interval between the Q wave and the T wave on the electrocardiogram. This abnormality reflects a prolongation of the ventricular action potential caused by a number of genetic mutations or a variety of drugs. Since effective treatments are unavailable, we explored the possibility of using cardiac expression of the large-conductance, Ca2+-activated K+ (BK) channel to shorten action potential duration (APD). We hypothesized that expression of the pore-forming α subunit of human BK channels (hBKα) in HL-1 cells would shorten action potential duration in this mouse atrial cell line. Expression of hBKα had minimal effects on expression levels of other ion channels with the exception of a small but significant reduction in Kv11.1. Patch-clamped hBKα expressing HL-1 cells exhibited an outward voltage- and Ca2+-sensitive K+ current, which was inhibited by the BK channel blocker iberiotoxin (100 nM). This BK current phenotype was not detected in untransfected HL-1 cells or in HL-1 null cells sham-transfected with an empty vector. Importantly, APD in hBKα-expressing HL-1 cells averaged 14.3 ± 2.8 ms (n = 10), which represented a 53% reduction in APD compared to HL-1 null cells lacking BKα expression. APD in the latter cells averaged 31.0 ± 5.1 ms (n = 13). The shortened APD in hBKα-expressing cells was restored to normal duration by 100 nM iberiotoxin, suggesting that a repolarizing K+ current attributed to BK channels accounted for action potential shortening. These findings provide initial proof-of-concept that the introduction of hBKα channels into a cardiac cell line can shorten APD, and raise the possibility that gene-based interventions to increase hBKα channels in cardiac cells may hold promise as a therapeutic strategy for long QT syndrome. PMID:26091273

  18. U.S. Geological Survey Scientific Activities in the Exploration of Antarctica: Introduction to Antarctica (Including USGS Field Personnel: 1946-59)

    USGS Publications Warehouse

    Tony K. Meunier Edited by Williams, Richard S.; Ferrigno, Jane G.

    2007-01-01

    international) programs in biology, geology, geophysics, hydrology, and mapping. Therefore, the USGS was the obvious choice for these tasks, because it already had a professional staff of experienced mapmakers, scientists, and program managers with the foresight, dedication, and understanding of the need for accurate maps to support the science programs in Antarctica when asked to do so by the U.S. National Academy of Sciences. Public Laws 85-743 and 87-626, signed in August 1958, and in September 1962, respectively, authorized the Secretary, U.S. Department of the Interior, through the USGS, to support mapping and scientific work in Antarctica (Meunier, 1979 [2007], appendix A). Open-File Report 2006-1116 includes scanned facsimiles of postal cachets. It has become an international practice to create postal cachets to commemorate special events and projects in Antarctica. A cachet is defined as a seal or commemorative design printed or stamped on an envelope to mark a philatelic or special event. The inked impression illustrates to the scientist, historian, stamp collector, and general public the multidisciplinary science projects staffed by USGS and collaborating scientists during the field season. Since 1960, philatelic cachets have been created by team members for each USGS field season and, in most cases, these cachets depict the specific geographic areas and field season program objectives. The cachets become a convenient documentation of the people, projects, and geographic places of interest for that year. Because the cachets are representative of USGS activities, each year's cachet is included as a digital facsimile in that year's Open-File Report. In the 1980s, multiple USGS cachets were prepared each year, one for use by the winter team at Amundsen-Scott South Pole Station and the other for the project work areas of the austral summer field season programs.

  19. In vitro activity of ceftazidime/avibactam against Gram-negative pathogens isolated from pneumonia in hospitalised patients, including ventilated patients.

    PubMed

    Flamm, Robert K; Nichols, Wright W; Sader, Helio S; Farrell, David J; Jones, Ronald N

    2016-03-01

    The activities of the novel β-lactam/non-β-lactam β-lactamase inhibitor combination ceftazidime/avibactam and comparators were evaluated against isolates from pneumonia in hospitalised patients including ventilated patients (PHP, pneumonia not designated as VABP; VABP, pneumonia in ventilated patients). Isolates were from the European-Mediterranean region (EuM), China and the USA collected in the SENTRY Antimicrobial Surveillance Program between 2009 and 2011 inclusive. A total of 2393 organisms from PHP were from the EuM, 888 from China and 3213 from the USA; from VABP patients there were 918, 97 and 692 organisms collected, respectively. Among Enterobacteriaceae from PHP, ceftazidime/avibactam MIC90 values against Escherichia coli ranged from 0.25-0.5mg/L and Klebsiella spp. MIC90 values were 0.5mg/L in each region. Among VABP isolates, MIC90 values for ceftazidime/avibactam against E. coli were 0.25mg/L; for Klebsiella spp. from VABP patients, MIC90 values were similar to those obtained against PHP isolates. The MIC of ceftazidime/avibactam was ≤8mg/L against 92-96% of Pseudomonas aeruginosa isolated from PHP patients. Isolates of P. aeruginosa from VABP patients were of lower susceptibility to all antibacterial agents (e.g. depending on region, meropenem susceptibilities were 51.2-69.4% in contrast to 68.3-76.7% among PHP patients). However, ceftazidime/avibactam inhibited 79.2-95.4% of VABP isolates at an MIC of ≤8mg/L. Acinetobacter spp. were resistant to many agents and only rates of susceptibility to colistin were >90% across all regions both for PHP and VABP isolates. Ceftazidime/avibactam was generally active against a high proportion of isolates resistant to ceftazidime from PHP and VAPB patients.

  20. Brain activity mapping in Mecp2 mutant mice reveals functional deficits in forebrain circuits, including key nodes in the default mode network, that are reversed with ketamine treatment.

    PubMed

    Kron, Miriam; Howell, C James; Adams, Ian T; Ransbottom, Michael; Christian, Diana; Ogier, Michael; Katz, David M

    2012-10-01

    Excitatory-inhibitory imbalance has been identified within specific brain microcircuits in models of Rett syndrome (RTT) and other autism spectrum disorders (ASDs). However, macrocircuit dysfunction across the RTT brain as a whole has not been defined. To approach this issue, we mapped expression of the activity-dependent, immediate-early gene product Fos in the brains of wild-type (Wt) and methyl-CpG-binding protein 2 (Mecp2)-null (Null) mice, a model of RTT, before and after the appearance of overt symptoms (3 and 6 weeks of age, respectively). At 6 weeks, Null mice exhibit significantly less Fos labeling than Wt in limbic cortices and subcortical structures, including key nodes in the default mode network. In contrast, Null mice exhibit significantly more Fos labeling than Wt in the hindbrain, most notably in cardiorespiratory regions of the nucleus tractus solitarius (nTS). Using nTS as a model, whole-cell recordings demonstrated that increased Fos expression in Nulls at 6 weeks of age is associated with synaptic hyperexcitability, including increased frequency of spontaneous and miniature EPSCs and increased amplitude of evoked EPSCs in Nulls. No such effect of genotype on Fos or synaptic function was seen at 3 weeks. In the mutant forebrain, reduced Fos expression, as well as abnormal sensorimotor function, were reversed by the NMDA receptor antagonist ketamine. In light of recent findings that the default mode network is hypoactive in autism, our data raise the possibility that hypofunction within this meta-circuit is a shared feature of RTT and other ASDs and is reversible. PMID:23035095

  1. Electrical Conductivity.

    ERIC Educational Resources Information Center

    Allen, Philip B.

    1979-01-01

    Examines Drude's classical (1900) theory of electrical conduction, details the objections to and successes of the 1900 theory, and investigates the Quantum (1928) theory of conduction, reviewing its successes and limitations. (BT)

  2. Self-Healing Conductive Injectable Hydrogels with Antibacterial Activity as Cell Delivery Carrier for Cardiac Cell Therapy.

    PubMed

    Dong, Ruonan; Zhao, Xin; Guo, Baolin; Ma, Peter X

    2016-07-13

    Cell therapy is a promising strategy to regenerate cardiac tissue for myocardial infarction. Injectable hydrogels with conductivity and self-healing ability are highly desirable as cell delivery vehicles for cardiac regeneration. Here, we developed self-healable conductive injectable hydrogels based on chitosan-graft-aniline tetramer (CS-AT) and dibenzaldehyde-terminated poly(ethylene glycol) (PEG-DA) as cell delivery vehicles for myocardial infarction. Self-healed electroactive hydrogels were obtained after mixing CS-AT and PEG-DA solutions at physiological conditions. Rapid self-healing behavior was investigated by rheometer. Swelling behavior, morphology, mechanical strength, electrochemistry, conductivity, adhesiveness to host tissue and antibacterial property of the injectable hydrogels were fully studied. Conductivity of the hydrogels is ∼10(-3) S·cm(-1), which is quite close to native cardiac tissue. Proliferation of C2C12 myoblasts in the hydrogel showed its good biocompatibility. After injection, viability of C2C12 cells in the hydrogels showed no significant difference with that before injection. Two different cell types were successfully encapsulated in the hydrogels by self-healing effect. Cell delivery profile of C2C12 myoblasts and H9c2 cardiac cells showed a tunable release rate, and in vivo cell retention in the conductive hydrogels was also studied. Subcutaneous injection and in vivo degradation of the hydrogels demonstrated their injectability and biodegradability. Together, these self-healing conductive biodegradable injectable hydrogels are excellent candidates as cell delivery vehicle for cardiac repair. PMID:27311127

  3. Challenges and solutions in the bioanalysis of BMS-986094 and its metabolites including a highly polar, active nucleoside triphosphate in plasma and tissues using LC-MS/MS.

    PubMed

    Liu, Ang; Lute, John; Gu, Huidong; Wang, Bonnie; Trouba, Kevin J; Arnold, Mark E; Aubry, Anne-Françoise; Wang, Jian

    2015-09-01

    BMS-986094, a nucleotide polymerase inhibitor of the hepatitis C virus, was withdrawn from clinical trials because of a serious safety issue. To investigate a potential association between drug/metabolite exposure and toxicity in evaluations conducted after the termination of the BMS-986094 development program, it was essential to determine the levels of BMS-986094 and its major metabolites INX-08032, INX-08144 and INX-09054 in circulation and the active nucleoside triphosphate INX-09114 in target and non-target tissues. However, there were many challenges in the bioanalysis of these compounds. The chromatography challenge for the extremely polar nucleoside triphosphate was solved by applying mixed-mode chromatography which combined anion exchange and reversed-phase interactions. The LC conditions provided adequate retention and good peak shape of the analyte and showed good robustness. A strategy using simultaneous extraction but separate LC analysis of the prodrug BMS-986094 and its major circulating metabolites was used to overcome a carryover issue of the hydrophobic prodrug while still achieving good chromatography of the polar metabolites. In addition, the nucleotide analytes were not stable in the presence of endogenous enzymes. Low pH and low temperature were required for blood collection and plasma sample processing. However, the use of phosphatase inhibitor and immediate homogenization and extraction were critical for the quantitative analysis of the active triphosphate, INX-09114, in tissue samples. To alleviate the bioanalytical complexity caused by multiple analytes, different matrices, and various species, a fit-for-purpose approach to assay validation was implemented based on the needs of drug safety assessment in non-clinical (GLP or non-GLP) studies. The assay for INX-08032 was fully validated in plasma of toxicology species. The lower limit of quantification was 1.00ng/mL and the linear curve range was 1.00-500.00ng/mL using a weighted (1/x(2

  4. Challenges and solutions in the bioanalysis of BMS-986094 and its metabolites including a highly polar, active nucleoside triphosphate in plasma and tissues using LC-MS/MS.

    PubMed

    Liu, Ang; Lute, John; Gu, Huidong; Wang, Bonnie; Trouba, Kevin J; Arnold, Mark E; Aubry, Anne-Françoise; Wang, Jian

    2015-09-01

    BMS-986094, a nucleotide polymerase inhibitor of the hepatitis C virus, was withdrawn from clinical trials because of a serious safety issue. To investigate a potential association between drug/metabolite exposure and toxicity in evaluations conducted after the termination of the BMS-986094 development program, it was essential to determine the levels of BMS-986094 and its major metabolites INX-08032, INX-08144 and INX-09054 in circulation and the active nucleoside triphosphate INX-09114 in target and non-target tissues. However, there were many challenges in the bioanalysis of these compounds. The chromatography challenge for the extremely polar nucleoside triphosphate was solved by applying mixed-mode chromatography which combined anion exchange and reversed-phase interactions. The LC conditions provided adequate retention and good peak shape of the analyte and showed good robustness. A strategy using simultaneous extraction but separate LC analysis of the prodrug BMS-986094 and its major circulating metabolites was used to overcome a carryover issue of the hydrophobic prodrug while still achieving good chromatography of the polar metabolites. In addition, the nucleotide analytes were not stable in the presence of endogenous enzymes. Low pH and low temperature were required for blood collection and plasma sample processing. However, the use of phosphatase inhibitor and immediate homogenization and extraction were critical for the quantitative analysis of the active triphosphate, INX-09114, in tissue samples. To alleviate the bioanalytical complexity caused by multiple analytes, different matrices, and various species, a fit-for-purpose approach to assay validation was implemented based on the needs of drug safety assessment in non-clinical (GLP or non-GLP) studies. The assay for INX-08032 was fully validated in plasma of toxicology species. The lower limit of quantification was 1.00ng/mL and the linear curve range was 1.00-500.00ng/mL using a weighted (1/x(2

  5. The slow and the quick anion conductance in whole guard cells: their voltage-dependent alternation, and the modulation of their activities by abscisic acid and CO2.

    PubMed

    Raschke, Klaus; Shabahang, Mahbobeh; Wolf, Rupert

    2003-08-01

    We explored the functioning of the slowly activating anion conductance, S-type or SLAC, and of the quickly activating anion conductance, R-type or QUAC, in whole guard cells of Vicia faba L.; details of QUAC activity had not previously been demonstrated in guard cells possessing their walls. The discontinuous single-electrode voltage-clamp method was used to record current responses to voltage pulses and voltage ramps as well as the free-running membrane voltage. At all voltages tested between -200 and 60 mV, SLAC activated with two components, one had a time constant similar to 7 s, the other similar to 40 s. The current-voltage relationship resembled that obtained by patch-clamp experiments. In pulse experiments and 1-s ramps, QUAC activity appeared with half-maximum activation near -50 mV and full activation above -10 mV; it inactivated with a half-time of approximately 10 s. Inactivation of QUAC at -40 mV led to the appearance of SLAC. After deactivation of SLAC at -200 mV, QUAC could be activated again. We concluded that voltage-dependent interchanges between SLAC and QUAC had occurred. Frequently, SLAC and QUAC were active simultaneously in the same cell. Abscisic acid (ABA, 20 microM) activated SLAC as well as QUAC. External Ca2+ was not required, but enhanced the activation of QUAC. Rises in the partial pressure of CO2, in the range between 0 and 700 microbar, caused rapid and reversible increases in the activity of SLAC (and outward currents of K+). QUAC also responded to CO2, however in an unpredictable manner (either by increased or by decreased activity). Oscillations in the free-running membrane voltage arose either spontaneously or after changes in CO2. They were correlated with periodic activations and inactivations of QUAC and required the simultaneous activity of an electrogenic pump.

  6. 40 CFR 745.227 - Work practice standards for conducting lead-based paint activities: target housing and child...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Lead-Based Paint, Lead-Contaminated Dust, and Lead-Contaminated Soil; the EPA Residential Sampling for Lead: Protocols for Dust and Soil Sampling (EPA report number 7474-R-95-001); Regulations, guidance... Contaminiated Soil or other equivalent guidelines. (b) Inspection. (1) An inspection shall be conducted only...

  7. 40 CFR 745.227 - Work practice standards for conducting lead-based paint activities: target housing and child...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Lead-Based Paint, Lead-Contaminated Dust, and Lead-Contaminated Soil; the EPA Residential Sampling for Lead: Protocols for Dust and Soil Sampling (EPA report number 7474-R-95-001); Regulations, guidance... Contaminiated Soil or other equivalent guidelines. (b) Inspection. (1) An inspection shall be conducted only...

  8. 40 CFR 745.227 - Work practice standards for conducting lead-based paint activities: target housing and child...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Lead-Based Paint, Lead-Contaminated Dust, and Lead-Contaminated Soil; the EPA Residential Sampling for Lead: Protocols for Dust and Soil Sampling (EPA report number 7474-R-95-001); Regulations, guidance... Contaminiated Soil or other equivalent guidelines. (b) Inspection. (1) An inspection shall be conducted only...

  9. 40 CFR 745.227 - Work practice standards for conducting lead-based paint activities: target housing and child...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Lead-Based Paint, Lead-Contaminated Dust, and Lead-Contaminated Soil; the EPA Residential Sampling for Lead: Protocols for Dust and Soil Sampling (EPA report number 7474-R-95-001); Regulations, guidance... Contaminiated Soil or other equivalent guidelines. (b) Inspection. (1) An inspection shall be conducted only...

  10. 40 CFR 745.227 - Work practice standards for conducting lead-based paint activities: target housing and child...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Lead-Based Paint, Lead-Contaminated Dust, and Lead-Contaminated Soil; the EPA Residential Sampling for Lead: Protocols for Dust and Soil Sampling (EPA report number 7474-R-95-001); Regulations, guidance... Contaminiated Soil or other equivalent guidelines. (b) Inspection. (1) An inspection shall be conducted only...

  11. 78 FR 24161 - Takes of Marine Mammals Incidental to Specified Activities; Navy Training Conducted at the Silver...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-24

    .... ACTION: Notice; proposed incidental harassment authorization; request for comments. SUMMARY: NMFS has received a complete application from the U.S. Navy (Navy) for an Incidental Harassment Authorization (IHA) to take marine mammals, by harassment, incidental to conducting training exercises at the...

  12. 77 FR 19231 - Takes of Marine Mammals Incidental to Specified Activities; Navy Training Conducted at the Silver...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-30

    .... ACTION: Notice; additional information for the proposed incidental harassment authorization; request for comments. SUMMARY: NMFS has received an application from the U.S. Navy (Navy) for an Incidental Harassment Authorization (IHA) to take marine mammals, by harassment, incidental to conducting training exercises at...

  13. The cation selectivity and voltage dependence of the light-activated potassium conductance in scallop distal photoreceptor.

    PubMed Central

    Cornwall, M C; Gorman, A L

    1983-01-01

    Light-dependent voltage and current responses were measured from the distal hyperpolarizing photoreceptors of the scallop (Pecten irradians) retina. In normal external solution, the hyperpolarizing receptor potential was caused by a light-dependent K+ outward current. The magnitude of the hyperpolarizing receptor potential and the light-dependent outward current, measured at the resting potential, was graded with light intensity. In normal external solution, during prolonged illumination the light-dependent K+ outward current was characterized by an early peak and a subsequent plateau. Current responses to brief light flashes were reduced progressively during background illumination. In the absence of external Na+ ions, the reversal potential for the receptor potential changed 58 mV per 10-fold change in the extracellular K+ concentration. The estimated internal K+ concentration was 385 mM. The hyperpolarizing receptor potential produced by prolonged bright illumination consists of an early peak which decays to a plateau. This decay was determined by a decrease in the light-dependent K+ conductance during maintained illumination. The light-dependent conductance pathway passed outward currents better than inward K+ currents. The light-dependent K+ conductance was estimated to increase e-fold per 23-34 mV depolarization at the peak and during the plateau of the light response. The light-dependent conductance pathway was highly selective for K+ ions. The selectivity sequence for monovalent cations was T1+, K+ greater than Rb+ greater than NH4 greater than Cs+, Li+, Na+. External caesium and tetraethylammonium blocked inward but not outward K+ currents through the light-dependent K+ conductance pathway. The data suggest that K+ ions move through an aqueous pore which is controlled by light. PMID:6887051

  14. 34 CFR 303.15 - Include; including.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Include; including. 303.15 Section 303.15 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION EARLY INTERVENTION PROGRAM FOR INFANTS AND TODDLERS...

  15. Kinetics of Hydrogen Radical Reactions with Toluene Including Chemical Activation Theory Employing System-Specific Quantum RRK Theory Calibrated by Variational Transition State Theory.

    PubMed

    Bao, Junwei Lucas; Zheng, Jingjing; Truhlar, Donald G

    2016-03-01

    Pressure-dependent reactions are ubiquitous in combustion and atmospheric chemistry. We employ a new calibration procedure for quantum Rice-Ramsperger-Kassel (QRRK) unimolecular rate theory within a chemical activation mechanism to calculate the pressure-falloff effect of a radical association with an aromatic ring. The new theoretical framework is applied to the reaction of H with toluene, which is a prototypical reaction in the combustion chemistry of aromatic hydrocarbons present in most fuels. Both the hydrogen abstraction reactions and the hydrogen addition reactions are calculated. Our system-specific (SS) QRRK approach is adjusted with SS parameters to agree with multistructural canonical variational transition state theory with multidimensional tunneling (MS-CVT/SCT) at the high-pressure limit. The new method avoids the need for the usual empirical estimations of the QRRK parameters, and it eliminates the need for variational transition state theory calculations as a function of energy, although in this first application we do validate the falloff curves by comparing SS-QRRK results without tunneling to multistructural microcanonical variational transition state theory (MS-μVT) rate constants without tunneling. At low temperatures, the two approaches agree well with each other, but at high temperatures, SS-QRRK tends to overestimate falloff slightly. We also show that the variational effect is important in computing the energy-resolved rate constants. Multiple-structure anharmonicity, torsional-potential anharmonicity, and high-frequency-mode vibrational anharmonicity are all included in the rate computations, and torsional anharmonicity effects on the density of states are investigated. Branching fractions, which are both temperature- and pressure-dependent (and for which only limited data is available from experiment), are predicted as a function of pressure. PMID:26841076

  16. Kinetics of Hydrogen Radical Reactions with Toluene Including Chemical Activation Theory Employing System-Specific Quantum RRK Theory Calibrated by Variational Transition State Theory.

    PubMed

    Bao, Junwei Lucas; Zheng, Jingjing; Truhlar, Donald G

    2016-03-01

    Pressure-dependent reactions are ubiquitous in combustion and atmospheric chemistry. We employ a new calibration procedure for quantum Rice-Ramsperger-Kassel (QRRK) unimolecular rate theory within a chemical activation mechanism to calculate the pressure-falloff effect of a radical association with an aromatic ring. The new theoretical framework is applied to the reaction of H with toluene, which is a prototypical reaction in the combustion chemistry of aromatic hydrocarbons present in most fuels. Both the hydrogen abstraction reactions and the hydrogen addition reactions are calculated. Our system-specific (SS) QRRK approach is adjusted with SS parameters to agree with multistructural canonical variational transition state theory with multidimensional tunneling (MS-CVT/SCT) at the high-pressure limit. The new method avoids the need for the usual empirical estimations of the QRRK parameters, and it eliminates the need for variational transition state theory calculations as a function of energy, although in this first application we do validate the falloff curves by comparing SS-QRRK results without tunneling to multistructural microcanonical variational transition state theory (MS-μVT) rate constants without tunneling. At low temperatures, the two approaches agree well with each other, but at high temperatures, SS-QRRK tends to overestimate falloff slightly. We also show that the variational effect is important in computing the energy-resolved rate constants. Multiple-structure anharmonicity, torsional-potential anharmonicity, and high-frequency-mode vibrational anharmonicity are all included in the rate computations, and torsional anharmonicity effects on the density of states are investigated. Branching fractions, which are both temperature- and pressure-dependent (and for which only limited data is available from experiment), are predicted as a function of pressure.

  17. U.S. Geological Survey Scientific Activities in the Exploration of Antarctica: Introduction to Antarctica (Including USGS Field Personnel: 1946-59)

    USGS Publications Warehouse

    Tony K. Meunier Edited by Williams, Richard S.; Ferrigno, Jane G.

    2007-01-01

    3) significant changes that have occurred in Antarctic exploration and research since World War II will be discussed at the end of this report. Subsequent Open-File Reports will provide a year-by-year documentation of USGS scientific activities and accomplishments in Antarctica beginning with the post-IGY, 1959-60 research team. One Open-File Report is planned to be written for each field-based season. For an example of the series format, see Open-File Reports 2006-1113 (Meunier, 2007a) and 2006-1114 (Meunier, 2007b). This report is a companion document to Open-File Report 2006-1116 (Meunier, 2007c). The USGS mapping and science programs in Antarctica are among the longest continuously funded projects in the United States Antarctic Program (USAP). The 2005-06 field season is the 56th consecutive U.S. expedition in which USGS scientists have been participants, starting in 1946. USGS and the National Science Foundation (NSF) cooperation began with the establishment by NSF of the U.S. Antarctic (Research) Program [USA(R)P] in 1958-59 under Operation Deep Freeze IV (DF IV) and was given the responsibility for the principal coordination and management of all U.S. scientific activities in Antarctica in Deep Freeze 60 (DF 60) (1959-60). Financial support from NSF, mostly in the form of Memorandum of Understandings (MOUs) and Cooperative Agreements, extends back to this period and can be attributed to the need for accurate geologic, geophysical, and topographic base maps of specific field areas or regions where NSF-funded science projects were planned. The epoch of Antarctic exploration during the IGY was driven by science and, in a spirit of peaceful cooperation, the international scientific community wanted to limit military activities on the continent to logistical support (Meunier, 1979 [2007], p. 38). The USGS, a Federal civilian science agency in the Department of the Interior, has, since its founding in 1879, carried out numerous field-based national (and some

  18. Conduction mechanisms in P(VDF-TrFE)/gold nanowire composites: tunnelling and thermally-activated hopping process near the percolation threshold

    NASA Astrophysics Data System (ADS)

    Ramachandran, Laavanya; Lonjon, Antoine; Demont, Philippe; Dantras, Eric; Lacabanne, Colette

    2016-08-01

    High-aspect ratio gold nanowires were dispersed in a P(VDF-TrFE) matrix to form conducting polymer composites. The composites were found to follow a percolation law, with a low percolation threshold of 2.2%vol and attaining a conductivity value of 100 S m‑1. The temperature and frequency dependence of the composites were studied using broadband dielectric spectroscopy. Tunnelling was found to be the main charge transport mechanism at temperatures below ‑100 °C and a thermally-activated hopping mechanism was determined to be responsible for conduction at temperatures above ‑100 °C. The correlated barrier hopping model was found to be the best fit to explain the conduction mechanisms in the composites.

  19. Conduction mechanisms in P(VDF-TrFE)/gold nanowire composites: tunnelling and thermally-activated hopping process near the percolation threshold

    NASA Astrophysics Data System (ADS)

    Ramachandran, Laavanya; Lonjon, Antoine; Demont, Philippe; Dantras, Eric; Lacabanne, Colette

    2016-08-01

    High-aspect ratio gold nanowires were dispersed in a P(VDF-TrFE) matrix to form conducting polymer composites. The composites were found to follow a percolation law, with a low percolation threshold of 2.2%vol and attaining a conductivity value of 100 S m-1. The temperature and frequency dependence of the composites were studied using broadband dielectric spectroscopy. Tunnelling was found to be the main charge transport mechanism at temperatures below -100 °C and a thermally-activated hopping mechanism was determined to be responsible for conduction at temperatures above -100 °C. The correlated barrier hopping model was found to be the best fit to explain the conduction mechanisms in the composites.

  20. Modified conducting polymer films having high catalytic activity for use as counter electrodes in rigid and flexible dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ke, Chun-Ren; Chang, Chih-Ching; Ting, Jyh-Ming

    2015-06-01

    We report replacing platinum based counter electrode (CE) in dye-sensitized solar cell (DSSC) with conducting polymer based CE. Conducting polymers are prepared through mixing poly-(3,4-ethylenedioxythio phene):poly-(styrene sulfonic acid) (PEDOT:PSS) with Triton. The polymer mixture is spin-coated on indium tin oxide (ITO)-coated glass substrate and ITO-coated polyethylene naphthalate plastic substrate to form a CE for use in both rigid and flexible DSSCs, respectively. The PEDOT:PSS-Triton polymer not only is transparent (up to 93%) and highly conductive but also exhibits better catalytic activity than the expensive platinum. The DSSC fabricated using the PEDOT:PSS-Triton conducting polymer CE shows better performance or higher power conversion efficiency than that using Pt-based CE, either rigid or flexible.

  1. 30 CFR 250.210 - If I conduct ancillary activities, what reporting and data/information retention requirements...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... reporting and data/information retention requirements must I satisfy? 250.210 Section 250.210 Mineral... ancillary activities, what reporting and data/information retention requirements must I satisfy? (a... data or information obtained or derived from your ancillary activities. When applicable, MMS...

  2. Conducting Museum Education Activities within the Context of Developing a Nature Culture in Primary School Students: MTA Natural History Museum Example

    ERIC Educational Resources Information Center

    Dilli, Rukiye

    2016-01-01

    The present study, aiming to develop nature culture in primary school students and to help them to become acquainted with their close environment, is a quasi-experimental study. Museum education activities were conducted with the study group which consisted of 128 fourth-grade primary school students. At the end of the study, the students gained…

  3. 30 CFR 285.600 - What plans and information must I submit to MMS before I conduct activities on my lease or grant?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What plans and information must I submit to MMS before I conduct activities on my lease or grant? 285.600 Section 285.600 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE RENEWABLE ENERGY ALTERNATE USES OF...

  4. 30 CFR 250.201 - What plans and information must I submit before I conduct any activities on my lease or unit?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS... may cover one or more leases or units. You must submit a(n) . . . Before you . . . (1) Exploration Plan (EP) Conduct any exploration activities on a lease or unit. (2) Development and Production...

  5. Training and Technology. Report of Program Activities January 1--June 30, 1973. Conducted at the U.S. Atomic Energy Commissions Oak Ridge Y-12 Plant. Summary Report.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN. Manpower Development Div.

    The report is a description of the program activities carried on by Training and Technology (TAT) during the first six months of 1973. In the general category of manpower research and development, brief but detailed descriptions are given of each of the projects conducted in the development and extension of the TAT training model in Albuquerque,…

  6. 43 CFR 2884.25 - What activities may I conduct on BLM lands covered by my application for a grant or TUP while BLM...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false What activities may I conduct on BLM lands covered by my application for a grant or TUP while BLM is processing my application? 2884.25 Section 2884.25 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR LAND...

  7. 43 CFR 2804.29 - What activities may I conduct on the lands covered by the proposed right-of-way while BLM is...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false What activities may I conduct on the lands covered by the proposed right-of-way while BLM is processing my application? 2804.29 Section 2804.29 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR LAND...

  8. 12 CFR 303.187 - Approval for an insured state branch of a foreign bank to conduct activities not permissible for...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Approval for an insured state branch of a... Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE FILING PROCEDURES International Banking § 303.187 Approval for an insured state branch of a foreign bank to conduct activities...

  9. Electrical measurements in the atmosphere and the Ionosphere over an active thunderstorm. II - Direct current electric fields and conductivity

    NASA Technical Reports Server (NTRS)

    Holzworth, R. H.; Kelley, M. C.; Siefring, C. L.; Hale, L. C.; Mitchell, J. D.

    1985-01-01

    On August 9, 1981, a series of three rockets was launched over an air mass thunderstorm off the eastern seaboard of Virginia while simultaneous stratospheric and ground-based electric field measurements were made. The conductivity was substantially lower at most altitudes than the conductivity profiles used by theoretical models. Direct current electric fields over 80 mV/m were measured as far away as 96 km from the storm in the stratosphere at 23 km altitude. No dc electric fields above 75 km altitude could be identified with the thunderstorm, in agreement with theory. However, vertical current densities over 120 pA/sq m were seen well above the classical 'electrosphere' (at 50 or 60 km). Frequent dc shifts in the electric field following lightning transients were seen by both balloon and rocket payloads. These dc shifts are clearly identifiable with either cloud-to-ground (increases) or intercloud (decreases) lightning flashes.

  10. Cyanoquinolines with Independent Corrector and Potentiator Activities Restore ΔPhe508-Cystic Fibrosis Transmembrane Conductance Regulator Chloride Channel Function in Cystic Fibrosis

    PubMed Central

    Phuan, Puay-Wah; Yang, Baoxue; Knapp, John M.; Wood, Alex B.; Lukacs, Gergely L.; Kurth, Mark J.

    2011-01-01

    The ΔPhe508 mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) protein impairs its folding, stability, and chloride channel gating. Although small molecules that separately correct defective ΔPhe508-CFTR folding/cellular processing (“correctors”) or chloride channel gating (“potentiators”) have been discovered and are in clinical trials, single compounds with bona fide dual corrector and potentiator activities have not been identified. Here, screening of ∼110,000 small molecules not tested previously revealed a cyanoquinoline class of compounds with independent corrector and potentiator activities (termed CoPo). Analysis of 180 CoPo analogs revealed 6 compounds with dual corrector and potentiator activities and 13 compounds with only potentiator activity. N-(2-((3-Cyano-5,7-dimethylquinolin-2-yl)amino)ethyl)-3-methoxybenzamide (CoPo-22), which was synthesized in six steps in 52% overall yield, had low micromolar EC50 for ΔPhe508-CFTR corrector and potentiator activities by short-circuit current assay. Maximal corrector and potentiator activities were comparable with those conferred by the bithiazole Corr-4a and the flavone genistein, respectively. CoPo-22 also activated wild-type and G551D CFTR chloride conductance within minutes in a forskolin-dependent manner. Compounds with dual corrector and potentiator activities may be useful for single-drug treatment of cystic fibrosis caused by ΔPhe508 mutation. PMID:21730204

  11. Metastable oxygen incorporation into thin film NiO by low temperature active oxidation: Influence on hole conduction

    SciTech Connect

    Aydogdu, Gulgun H.; Ruzmetov, Dmitry; Ramanathan, Shriram

    2010-12-01

    The ability to controllably tune cation valence state and resulting electrical conductivity of transition metal-oxides such as NiO is of great interest for a range of solid state electronic and energy devices and more recently in understanding electron correlation phenomena at complex oxide interfaces. Here, we demonstrate that it is possible to enhance electrical conductivity of NiO thin films by one order of magnitude by photoexcitation and three orders of magnitude by ozone treatment at as low as 310 K. The change occurs within nearly 2000 s and, thereafter, reaches a self-limiting value. A surprising difference is seen at 400 K: ultraviolet photon and ozone treatments cause only a marginal reduction in resistance in the first few minutes and, then, the resistance begins to increase and recovers its original value. This unusual reversal is explained by considering metastable incorporation of oxygen in NiO and oxygen equilibration with the environment. Variation in nickel valence state prior to and after photoexcitation and ozone treatment, investigated by x-ray photoelectron spectroscopy, provides mechanistic insights into resistance trends. This study demonstrates photon-assisted and ozone oxidation as effective low temperature routes to tune the electrical properties as well as metastably incorporate oxygen into oxides with direct influence on electrical conduction properties.

  12. Analysis of electro-active regions and conductivity of BaMnO3 ceramic by impedance spectroscopy

    NASA Astrophysics Data System (ADS)

    Hayat, Khizar; Nadeem, M.; Javid Iqbal, M.; Rafiq, M. A.; Hasan, M. M.

    2014-06-01

    Polycrystalline BaMnO3 ceramic powders were prepared using the conventional mixed oxide route accompanied with several milling processes. Single phase formation was verified by recording the X-ray diffraction pattern of the powder as well as sintered pellet at room temperature. Scanning electron micrograph and energy dispersive X-ray spectrum of cross-sectional view have shown that sintered pellet is highly porous and contains only Ba, Mn and O elements, respectively. Analysis of impedance spectroscopy was carried out via the complex impedance and complex modulus formalisms. These results have shown that BaMnO3 behave as semiconducting material. Furthermore, as a consequence of electrically inhomogeneous nature of the sample, it was observed that the electroactive regions (such as grain, grain boundary and sample-electrode interface) are overlapped in the applied frequency domain with dominant grain boundary effect. An equivalent circuit model ( R g C g)( R gb Q gb)( R e Q e) was employed to fit the temperature dependent impedance spectroscopy data. Study of grain and grain boundary conductivities suggest that grains are more conductive than grain boundaries and conduction mechanism followed correlated barrier hopping (CBH) model.

  13. Surface modification of polyacrylonitrile film by anchoring conductive polyaniline and determination of uricase adsorption capacity and activity

    NASA Astrophysics Data System (ADS)

    Bayramoğlu, Gülay; Metin, Ayşegul Ü.; Arıca, M. Yakup

    2010-09-01

    Polyacrylonitrile (PAN) films were modified with chemical polymerization of conductive polyaniline (PANI) in the presence of potassium dichromate as an oxidizing agent. The effect of aniline concentration on the grafting efficiency and on the electrical surface resistance of PAN and (PAN/PANI)-1-3 composite film was investigated. The surface resistances of the conductive composite films were found to be between 6.32 and 0.97 kΩ/cm. As the amount of grafted PANI increased on the PAN films, the electrical resistance of composite film decreased. The PAN/PANI composite films were also characterized using SEM and FTIR. The changes in the surface properties of the films were characterized by contact angle measurements. As expected, the PAN, PAN/PANI and PAN/PANI-uricase immobilized films, exhibited different contact angle values and surface free energy due to different interactive functional groups of the films. The conductive films were well characterized and used for immobilization of uricase. The amount of adsorbed enzyme increases with the increase of surface concentration of grafted fibrous polyaniline polymer. The maximum amount of immobilized enzyme onto composite film containing 2.4% PANI was about 216 μg/cm 2 (i.e., PAN/PANI-3). The immobilized uricase was reused 24 times in batch wise assay in a day. Finally, the immobilized uricase enzyme system was successfully fabricated and applied to determine the uric acid level in human serum samples.

  14. Conducting an Introductory Biology Course in an Active Learning Classroom: A Case Study of an Experienced Faculty Member

    ERIC Educational Resources Information Center

    Langley, David; Guzey, S. Selcen

    2014-01-01

    A case study is described that examines the beliefs and practices of a university instructor who teaches regularly in an active learning classroom. His perspective provides insights into the pedagogical practices that drive his success in these learning spaces.

  15. Effect of Exogenous Extracellular Nicotinamide Adenine Dinucleotide (NAD⁺) on Bioelectric Activity of the Pacemaker and Conduction System of the Heart.

    PubMed

    Pustovit, K B; Kuz'min, V S; Sukhova, G S

    2015-06-01

    In rat sinoatrial node, NAD(+) (10 μM) reduced the rate of spontaneous action potentials, duration of action potentials, and the velocity of slow diastolic depolarization, but the rate of action potential front propagation increases. In passed rabbit Purkinje fibers, NAD(+) (10 μM) reduced the duration of action potentials. Under conditions of spontaneous activity of Purkinje fibers, NAD(+) reduced the fi ring rate and the rate of slow diastolic depolarization. The effects of extracellular NAD(+) on bioelectric activity of the pacemaker (sinoatrial node) and conduction system of the heart (Purkinje fibers) are probably related to activation of P1 and P2 purinoceptors.

  16. Seed dormancy breaking diterpenoids, including novel brassicicenes J and K, from fungus Alternaria brassicicola, and their necrotic/apoptotic activities in HL-60 cells.

    PubMed

    Kenmoku, Hiromichi; Takeue, Sayaka; Oogushi, Megumi; Yagi, Yasuyuki; Sassa, Takeshi; Toyota, Masao; Asakawa, Yoshinori

    2014-03-01

    To find new metabolites similar to cotylenins and fusicoccins from the fungus Alternaria brassicicola, screening tests were carried out using the lettuce seed dormancy breaking assay. Activity-guided fractionation of the EtOAc extract from the culture using the assay afforded the isolation of two novel fusicoccane diterpenoids named brassicicenes J (1) and K (2), along with three known brassicicenes A (3), B (4), and F (5). Their structures were elucidated from extensive NMR spectral data and by comparison of these with those reported in the literature. Brassicicenes (1-5) exhibited weak to moderate seed dormancy breaking activities against lettuce seeds in the presence of abscisic acid. In addition, the necrotic/apoptotic activities of the brassicicenes (1-5), fusicoccin A (6) and cotylenin A (7) were evaluated by determining their cytotoxicity, cell viability and caspase-3/7 activation on the HL-60 cell line. Brassicicene K (2) exhibited similar cytostatic profiles to that of cotylenin A (7), and brassicicenes J (1), A (3), B (4), and F (5) exhibited necrotic activity. This is the first report of the seed dormancy breaking activity of brassicicenes in plants, and of necrotic/apoptotic activity in mammalian cells. PMID:24689212

  17. 30 CFR 550.210 - If I conduct ancillary activities, what reporting and data/information retention requirements...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR... navigation data, obtained or derived from your G&G explorations and development G&G activities (see § 550.207... submitted data and information in accordance with § 550.197(b). Contents of Exploration Plans (EP)...

  18. 30 CFR 550.210 - If I conduct ancillary activities, what reporting and data/information retention requirements...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR... navigation data, obtained or derived from your G&G explorations and development G&G activities (see § 550.207... submitted data and information in accordance with § 550.197(b). Contents of Exploration Plans (EP)...

  19. 30 CFR 550.210 - If I conduct ancillary activities, what reporting and data/information retention requirements...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR... navigation data, obtained or derived from your G&G explorations and development G&G activities (see § 550.207... submitted data and information in accordance with § 550.197(b). Contents of Exploration Plans (EP)...

  20. 30 CFR 285.803 - How must I conduct my approved activities to protect essential fish habitats identified and...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... protect essential fish habitats identified and described under the Magnuson-Stevens Fishery Conservation... activities to protect essential fish habitats identified and described under the Magnuson-Stevens Fishery... essential fish habitat or habitat areas of particular concern may be adversely affected by your...

  1. Electrical Conductivity.

    ERIC Educational Resources Information Center

    Hershey, David R.; Sand, Susan

    1993-01-01

    Explains how electrical conductivity (EC) can be used to measure ion concentration in solutions. Describes instrumentation for the measurement, temperature dependence and EC, and the EC of common substances. (PR)

  2. Time-lapse three-dimensional inversion of complex conductivity data using an active time constrained (ATC) approach

    USGS Publications Warehouse

    Karaoulis, M.; Revil, A.; Werkema, D.D.; Minsley, B.J.; Woodruff, W.F.; Kemna, A.

    2011-01-01

    Induced polarization (more precisely the magnitude and phase of impedance of the subsurface) is measured using a network of electrodes located at the ground surface or in boreholes. This method yields important information related to the distribution of permeability and contaminants in the shallow subsurface. We propose a new time-lapse 3-D modelling and inversion algorithm to image the evolution of complex conductivity over time. We discretize the subsurface using hexahedron cells. Each cell is assigned a complex resistivity or conductivity value. Using the finite-element approach, we model the in-phase and out-of-phase (quadrature) electrical potentials on the 3-D grid, which are then transformed into apparent complex resistivity. Inhomogeneous Dirichlet boundary conditions are used at the boundary of the domain. The calculation of the Jacobian matrix is based on the principles of reciprocity. The goal of time-lapse inversion is to determine the change in the complex resistivity of each cell of the spatial grid as a function of time. Each model along the time axis is called a 'reference space model'. This approach can be simplified into an inverse problem looking for the optimum of several reference space models using the approximation that the material properties vary linearly in time between two subsequent reference models. Regularizations in both space domain and time domain reduce inversion artefacts and improve the stability of the inversion problem. In addition, the use of the time-lapse equations allows the simultaneous inversion of data obtained at different times in just one inversion step (4-D inversion). The advantages of this new inversion algorithm are demonstrated on synthetic time-lapse data resulting from the simulation of a salt tracer test in a heterogeneous random material described by an anisotropic semi-variogram. ?? 2011 The Authors Geophysical Journal International ?? 2011 RAS.

  3. Validation of the Japanese version of the Systemic Lupus Activity Questionnaire that includes physician-based assessments in a large observational cohort.

    PubMed

    Okamoto, Y; Katsumata, Y; Baba, S; Kawaguchi, Y; Gono, T; Hanaoka, M; Kawasumi, H; Yamanaka, H

    2016-04-01

    The Systemic Lupus Activity Questionnaire (SLAQ) is a patient-reported outcome for systemic lupus erythematosus (SLE). We aimed to translate it into Japanese and further investigate its validity and reliability. The English version of the SLAQ was translated into Japanese and administered to Japanese SLE patients at our university clinic. Physicians assessed disease activity using the SLE Disease Activity Index 2000 (SLEDAI-2K). The patients were prospectively followed for repeat assessment a year later. Ultimately, 255 patients participated. The patients' 10-point ratings of disease activity and SLAQ scores were significantly correlated (Spearman's ρ = 0.53). The SLAQ score was weakly correlated with the SLE Disease Activity Index 2000 (SLEDAI-2K)-nolab (omitting laboratory items; ρ = 0.18) but not with the SLEDAI-2K (ρ = 0.02). These results suggested its convergent and discriminant validity. The SLAQ demonstrated acceptable internal consistency (Cronbach's α = 0.80), and good test-retest reliability (intraclass correlation coefficient = 0.85). The effect sizes and the standardized response means of the SLAQ were as follows: clinical worsening, 0.26 and 0.31, and improvement, -0.39 and -0.41, respectively, which indicated a small but significant responsiveness. The Japanese version of the SLAQ demonstrated acceptable reliability and validity; its performance was comparable to that of the original version.

  4. 30 CFR 250.210 - If I conduct ancillary activities, what reporting and data/information retention requirements...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR... information, including navigation data, obtained or derived from your G&G explorations and development G&G... disclose such submitted data and information in accordance with § 250.197(b). Contents of Exploration...

  5. Development of operational models of receptor activation including constitutive receptor activity and their use to determine the efficacy of the chemokine CCL17 at the CC chemokine receptor CCR4.

    PubMed

    Slack, R J; Hall, D A

    2012-07-01

    BACKGROUND AND PURPOSE The operational model provides a key conceptual framework for the analysis of pharmacological data. However, this model does not include constitutive receptor activity, a frequent phenomenon in modern pharmacology, particularly in recombinant systems. Here, we developed extensions of the operational model which include constitutive activity and applied them to effects of agonists at the chemokine receptor CCR4. EXPERIMENTAL APPROACH The effects of agonists of CCR4 on [(35) S]GTPγS binding to recombinant cell membranes and on the filamentous (F-) actin content of human CD4(+) CCR4(+) T cells were determined. The basal [(35) S]GTPγS binding was changed by varying the GDP concentration whilst the basal F-actin contents of the higher expressing T cell populations were elevated, suggesting constitutive activity of CCR4. Both sets of data were analysed using the mathematical models. RESULTS The affinity of CCL17 (also known as TARC) derived from analysis of the T cell data (pK(a) = 9.61 ± 0.17) was consistent with radioligand binding experiments (9.50 ± 0.11) while that from the [(35) S]GTPγS binding experiments was lower (8.27 ± 0.09). Its intrinsic efficacy differed between the two systems (110 in T cells vs. 11). CONCLUSIONS AND IMPLICATIONS The presence of constitutive receptor activity allows the absolute intrinsic efficacy of agonists to be determined without a contribution from the signal transduction system. Intrinsic efficacy estimated in this way is consistent with Furchgott's definition of this property. CCL17 may have a higher intrinsic efficacy at CCR4 in human T cells than that expressed recombinantly in CHO cells.

  6. On the recent seismic activity in North-Eastern Aegean Sea including the Mw5.8 earthquake on 8 January 2013

    PubMed Central

    SARLIS, Nicholas V.

    2013-01-01

    In the last week of November 2012, we announced that a strong electrotelluric disturbance, which we judged to be a Seismic Electric Signal (SES) activity, was recorded at station Assiros located in Northern Greece. This disturbance was actually followed by an Mw5.8 earthquake on 8 January 2013 in North-Eastern Aegean Sea. Here we show that, by analyzing this SES activity and employing the natural time analysis of subsequent seismicity, we estimated the epicentral location, magnitude and occurrence time which are reasonably compatible with those of the Mw5.8 event. PMID:24213207

  7. Electronic structure origin of conductivity and oxygen reduction activity changes in low-level Cr-substituted (La,Sr)MnO{sub 3}

    SciTech Connect

    Tsekouras, George Boudoire, Florent; Braun, Artur; Pal, Banabir; Sarma, D. D.; Vondráček, Martin; Prince, Kevin C.

    2015-09-21

    The electronic structure of the (La{sub 0.8}Sr{sub 0.2}){sub 0.98}Mn{sub 1−x}Cr{sub x}O{sub 3} model series (x = 0, 0.05, or 0.1) was measured using soft X-ray synchrotron radiation at room and elevated temperature. O K-edge near-edge X-ray absorption fine structure (NEXAFS) spectra showed that low-level chromium substitution of (La,Sr)MnO{sub 3} resulted in lowered hybridisation between O 2p orbitals and M 3d and M 4sp valance orbitals. Mn L{sub 3}-edge resonant photoemission spectroscopy measurements indicated lowered Mn 3d–O 2p hybridisation with chromium substitution. Deconvolution of O K-edge NEXAFS spectra took into account the effects of exchange and crystal field splitting and included a novel approach whereby the pre-peak region was described using the nominally filled t{sub 2g}↑ state. 10% chromium substitution resulted in a 0.17 eV lowering in the energy of the t{sub 2g}↑ state, which appears to provide an explanation for the 0.15 eV rise in activation energy for the oxygen reduction reaction, while decreased overlap between hybrid O 2p–Mn 3d states was in qualitative agreement with lowered electronic conductivity. An orbital-level understanding of the thermodynamically predicted solid oxide fuel cell cathode poisoning mechanism involving low-level chromium substitution on the B-site of (La,Sr)MnO{sub 3} is presented.

  8. Electronic structure origin of conductivity and oxygen reduction activity changes in low-level Cr-substituted (La,Sr)MnO3

    NASA Astrophysics Data System (ADS)

    Tsekouras, George; Boudoire, Florent; Pal, Banabir; Vondráček, Martin; Prince, Kevin C.; Sarma, D. D.; Braun, Artur

    2015-09-01

    The electronic structure of the (La0.8Sr0.2)0.98Mn1-xCrxO3 model series (x = 0, 0.05, or 0.1) was measured using soft X-ray synchrotron radiation at room and elevated temperature. O K-edge near-edge X-ray absorption fine structure (NEXAFS) spectra showed that low-level chromium substitution of (La,Sr)MnO3 resulted in lowered hybridisation between O 2p orbitals and M 3d and M 4sp valance orbitals. Mn L3-edge resonant photoemission spectroscopy measurements indicated lowered Mn 3d-O 2p hybridisation with chromium substitution. Deconvolution of O K-edge NEXAFS spectra took into account the effects of exchange and crystal field splitting and included a novel approach whereby the pre-peak region was described using the nominally filled t2g↑ state. 10% chromium substitution resulted in a 0.17 eV lowering in the energy of the t2g↑ state, which appears to provide an explanation for the 0.15 eV rise in activation energy for the oxygen reduction reaction, while decreased overlap between hybrid O 2p-Mn 3d states was in qualitative agreement with lowered electronic conductivity. An orbital-level understanding of the thermodynamically predicted solid oxide fuel cell cathode poisoning mechanism involving low-level chromium substitution on the B-site of (La,Sr)MnO3 is presented.

  9. Electrodeposition of chitosan/gelatin/nanosilver: A new method for constructing biopolymer/nanoparticle composite films with conductivity and antibacterial activity.

    PubMed

    Wang, Yifeng; Guo, Xuecheng; Pan, Ruihao; Han, Di; Chen, Tao; Geng, Zenghua; Xiong, Yanfei; Chen, Yanjun

    2015-08-01

    Electrodeposition of chitosan provides a controllable means to simultaneously assemble biological materials and nanoparticles for various applications. Here, we present a new method to construct biopolymer/nanoparticle composite films with conductivity and antibacterial activity by electrodeposition of chitosan/gelatin/nanosilver. Besides, this method can be employed to build biopolymer/nanoparticle composite hydrogels or coatings on various electrodes or conductive substrates. We initially use a simple approach to prepare the aqueous nanosilver that can be well-dispersed in water. Then, the codeposition mixture containing chitosan, gelatin and nanosilver is prepared, and it can be electrodeposited onto different electrodes or conductive substrates in response to imposed electrical signals. After electrodeposition, it is found that the deposited hydrogels and their dried films are smooth and homogeneous due to the elimination of H2 bubbles by addition of H2O2 in electrodeposition process. Importantly, the composite films are strong enough to completely and readily peel from the electrodes after they reacted with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), which can build a type of biopolymer/nanoparticle film for further applications. Furthermore, the electrodeposition technique is able to offer controllable and convenient method to construct the composite films with diverse shapes. The composite films display improved conductivity and in vitro antibacterial activity against Escherichia coli and Staphylococcus aureus, which may provide attractive applications in biomedical fields such as artificial muscles, skin biomaterials and neuroprosthetic implants.

  10. FBI-1 Can Stimulate HIV-1 Tat Activity and Is Targeted to a Novel Subnuclear Domain that Includes the Tat-P-TEFb—containing Nuclear Speckles

    PubMed Central

    Pendergrast, P. Shannon; Wang, Chen; Hernandez, Nouria; Huang, Sui

    2002-01-01

    FBI-1 is a cellular POZ-domain–containing protein that binds to the HIV-1 LTR and associates with the HIV-1 transactivator protein Tat. Here we show that elevated levels of FBI-1 specifically stimulate Tat activity and that this effect is dependent on the same domain of FBI-1 that mediates Tat-FBI-1 association in vivo. FBI-1 also partially colocalizes with Tat and Tat's cellular cofactor, P-TEFb (Cdk9 and cyclin T1), at the splicing-factor–rich nuclear speckle domain. Further, a less-soluble population of FBI-1 distributes in a novel peripheral-speckle pattern of localization as well as in other nuclear regions. This distribution pattern is dependent on the FBI-1 DNA binding domain, on the presence of cellular DNA, and on active transcription. Taken together, these results suggest that FBI-1 is a cellular factor that preferentially associates with active chromatin and that can specifically stimulate Tat-activated HIV-1 transcription. PMID:11907272

  11. FBI-1 can stimulate HIV-1 Tat activity and is targeted to a novel subnuclear domain that includes the Tat-P-TEFb-containing nuclear speckles.

    PubMed

    Pendergrast, P Shannon; Wang, Chen; Hernandez, Nouria; Huang, Sui

    2002-03-01

    FBI-1 is a cellular POZ-domain-containing protein that binds to the HIV-1 LTR and associates with the HIV-1 transactivator protein Tat. Here we show that elevated levels of FBI-1 specifically stimulate Tat activity and that this effect is dependent on the same domain of FBI-1 that mediates Tat-FBI-1 association in vivo. FBI-1 also partially colocalizes with Tat and Tat's cellular cofactor, P-TEFb (Cdk9 and cyclin T1), at the splicing-factor-rich nuclear speckle domain. Further, a less-soluble population of FBI-1 distributes in a novel peripheral-speckle pattern of localization as well as in other nuclear regions. This distribution pattern is dependent on the FBI-1 DNA binding domain, on the presence of cellular DNA, and on active transcription. Taken together, these results suggest that FBI-1 is a cellular factor that preferentially associates with active chromatin and that can specifically stimulate Tat-activated HIV-1 transcription.

  12. Electrophoretically active sol-gel processes to backfill, seal, and/or densify porous, flawed, and/or cracked coatings on electrically conductive material

    DOEpatents

    Panitz, J.K.; Reed, S.T.; Ashley, C.S.; Neiser, R.A.; Moffatt, W.C.

    1999-07-20

    Electrophoretically active sol-gel processes to fill, seal, and/or density porous, flawed, and/or cracked coatings on electrically conductive substrates. Such coatings may be dielectrics, ceramics, or semiconductors and, by the present invention, may have deposited onto and into them sol-gel ceramic precursor compounds which are subsequently converted to sol-gel ceramics to yield composite materials with various tailored properties. 6 figs.

  13. Electrophoretically active sol-gel processes to backfill, seal, and/or densify porous, flawed, and/or cracked coatings on electrically conductive material

    DOEpatents

    Panitz, Janda K.; Reed, Scott T.; Ashley, Carol S.; Neiser, Richard A.; Moffatt, William C.

    1999-01-01

    Electrophoretically active sol-gel processes to fill, seal, and/or density porous, flawed, and/or cracked coatings on electrically conductive substrates. Such coatings may be dielectrics, ceramics, or semiconductors and, by the present invention, may have deposited onto and into them sol-gel ceramic precursor compounds which are subsequently converted to sol-gel ceramics to yield composite materials with various tailored properties.

  14. Single-channel biophysical and pharmacological characterizations of native human large-conductance calcium-activated potassium channels in freshly isolated detrusor smooth muscle cells.

    PubMed

    Malysz, John; Rovner, Eric S; Petkov, Georgi V

    2013-07-01

    Recent studies have demonstrated the importance of large-conductance Ca(2+)-activated K(+) (BK) channels in detrusor smooth muscle (DSM) function in vitro and in vivo. However, in-depth characterization of human native DSM single BK channels has not yet been provided. Here, we conducted single-channel recordings from excised patches from native human DSM cells. Inside-out and outside-out recordings in high K(+) symmetrical solution (containing 140 mM KCl and ~300 nM free Ca(2+)) showed single-channel conductance of 215-220 pS, half-maximum constant for activation of ~+75 to +80 mV, and low probability of opening (P o) at +20 mV that increased ~10-fold at +40 mV and ~60-fold at +60 mV. Using the inside-out configuration at +30 mV, reduction of intracellular [Ca(2+)] from ~300 nM to Ca(2+)-free decreased the P o by ~85 %, whereas elevation to ~800 nM increased P o by ~50-fold. The BK channel activator NS1619 (10 μM) enhanced the P o by ~10-fold at +30 mV; subsequent application of the selective BK channel inhibitor paxilline (500 nM) blocked the activity. Changes in intracellular [Ca(2+)] or the addition of NS1619 did not significantly alter the current amplitude or single-channel conductance. This is the first report to provide biophysical and pharmacological profiles of native human DSM single BK channels highlighting their importance in regulating human DSM excitability.

  15. Path integration of head direction: updating a packet of neural activity at the correct speed using axonal conduction delays.

    PubMed

    Walters, Daniel; Stringer, Simon; Rolls, Edmund

    2013-01-01

    The head direction cell system is capable of accurately updating its current representation of head direction in the absence of visual input. This is known as the path integration of head direction. An important question is how the head direction cell system learns to perform accurate path integration of head direction. In this paper we propose a model of velocity path integration of head direction in which the natural time delay of axonal transmission between a linked continuous attractor network and competitive network acts as a timing mechanism to facilitate the correct speed of path integration. The model effectively learns a "look-up" table for the correct speed of path integration. In simulation, we show that the model is able to successfully learn two different speeds of path integration across two different axonal conduction delays, and without the need to alter any other model parameters. An implication of this model is that, by learning look-up tables for each speed of path integration, the model should exhibit a degree of robustness to damage. In simulations, we show that the speed of path integration is not significantly affected by degrading the network through removing a proportion of the cells that signal rotational velocity.

  16. Connexin37 forms high conductance gap junction channels with subconductance state activity and selective dye and ionic permeabilities.

    PubMed Central

    Veenstra, R D; Wang, H Z; Beyer, E C; Ramanan, S V; Brink, P R

    1994-01-01

    Gap junctions are thought to mediate the direct intercellular coupling of adjacent cells by the open-closed gating of an aqueous pore permeable to ions and molecules of up to 1 kDa or 10-14 A in diameter. We symmetrically altered the ionic composition or asymmetrically added 6-carboxyfluorescein (6-CF, M(r) = 376), a fluorescent tracer, to pairs of connexin37-transfected mouse neuro2A cells to examine the ionic and dye permeability of human connexin37 channels. We demonstrate that the 300-pS channel formed by connexin37 has an effective relative anion/cation permeability ratio of 0.43, directly converts to at least one intermediate (63 pS) subconductance state, and that 6-CF dye transfer is accompanied by a 24% decrease in unitary channel conductance. These observations favor a new interpretation of the gap junction pore consistent with direct ion-channel interactions or electrostatic charge effects common to more conventional multistate ion channels. These results have distinct implications about the different forms of intercellular signaling (cationic, ionic, and/or biochemical) that can occur depending on the expression and conformation of the connexin channel proteins. Images FIGURE 4 FIGURE 5 FIGURE 6 PMID:7521227

  17. A pilot study on conducting mobile learning activities for clinical nursing courses based on the repertory grid approach.

    PubMed

    Wu, Po-Han; Hwang, Gwo-Jen; Tsai, Chin-Chung; Chen, Ya-Chun; Huang, Yueh-Min

    2011-11-01

    In clinical nursing courses, students are trained to identify the status of the target patients. The mastery of such ability and skills is very important since patients frequently need to be cared for immediately. In this pilot study, a repertory grid-oriented clinical mobile learning system is developed for a nursing training program. With the assistance of the mobile learning system, the nursing school students are able to learn in an authentic learning scenario, in which they can physically face the target patients, with the personal guidance and supplementary materials from the learning system to support them. To show the effectiveness of this innovative approach, an experiment has been conducted on the "respiratory system" unit of a nursing course. The experimental results show that the innovative approach is helpful to students in improving their learning achievements. Moreover, from the questionnaire surveys, it was found that most students showed favorable attitudes toward the usage of the mobile learning system and their participation in the training program.

  18. Cystic Fibrosis Transmembrane Conductance Regulator Controls Lung Proteasomal Degradation and Nuclear Factor-κB Activity in Conditions of Oxidative Stress

    PubMed Central

    Boncoeur, Emilie; Roque, Telma; Bonvin, Elise; Saint-Criq, Vinciane; Bonora, Monique; Clement, Annick; Tabary, Olivier; Henrion-Caude, Alexandra; Jacquot, Jacky

    2008-01-01

    Cystic fibrosis is a lethal inherited disorder caused by mutations in a single gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein, resulting in progressive oxidative lung damage. In this study, we evaluated the role of CFTR in the control of ubiquitin-proteasome activity and nuclear factor (NF)-κB/IκB-α signaling after lung oxidative stress. After a 64-hour exposure to hyperoxia-mediated oxidative stress, CFTR-deficient (cftr−/−) mice exhibited significantly elevated lung proteasomal activity compared with wild-type (cftr+/+) animals. This was accompanied by reduced lung caspase-3 activity and defective degradation of NF-κB inhibitor IκB-α. In vitro, human CFTR-deficient lung cells exposed to oxidative stress exhibited increased proteasomal activity and decreased NF-κB-dependent transcriptional activity compared with CFTR-sufficient lung cells. Inhibition of the CFTR Cl− channel by CFTRinh-172 in the normal bronchial immortalized cell line 16HBE14o− increased proteasomal degradation after exposure to oxidative stress. Caspase-3 inhibition by Z-DQMD in CFTR-sufficient lung cells mimicked the response profile of increased proteasomal degradation and reduced NF-κB activity observed in CFTR-deficient lung cells exposed to oxidative stress. Taken together, these results suggest that functional CFTR Cl− channel activity is crucial for regulation of lung proteasomal degradation and NF-κB activity in conditions of oxidative stress. PMID:18372427

  19. Applying the model of Goal-Directed Behavior, including descriptive norms, to physical activity intentions: A contribution to improving the Theory of Planned Behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The theory of planned behavior (TPB) has received its fair share of criticism lately, including calls for it to retire. We contributed to improving the theory by testing extensions such as the model of goal-directed behavior (MGDB, which adds desire and anticipated positive and negative emotions) ap...

  20. EspC, an Autotransporter Protein Secreted by Enteropathogenic Escherichia coli, Causes Apoptosis and Necrosis through Caspase and Calpain Activation, Including Direct Procaspase-3 Cleavage

    PubMed Central

    Serapio-Palacios, Antonio

    2016-01-01

    ABSTRACT Enteropathogenic Escherichia coli (EPEC) has the ability to antagonize host apoptosis during infection through promotion and inhibition of effectors injected by the type III secretion system (T3SS), but the total number of these effectors and the overall functional relationships between these effectors during infection are poorly understood. EspC produced by EPEC cleaves fodrin, paxillin, and focal adhesion kinase (FAK), which are also cleaved by caspases and calpains during apoptosis. Here we show the role of EspC in cell death induced by EPEC. EspC is involved in EPEC-mediated cell death and induces both apoptosis and necrosis in epithelial cells. EspC induces apoptosis through the mitochondrial apoptotic pathway by provoking (i) a decrease in the expression levels of antiapoptotic protein Bcl-2, (ii) translocation of the proapoptotic protein Bax from cytosol to mitochondria, (iii) cytochrome c release from mitochondria to the cytoplasm, (iv) loss of mitochondrial membrane potential, (v) caspase-9 activation, (vi) cleavage of procaspase-3 and (vii) an increase in caspase-3 activity, (viii) PARP proteolysis, and (ix) nuclear fragmentation and an increase in the sub-G1 population. Interestingly, EspC-induced apoptosis was triggered through a dual mechanism involving both independent and dependent functions of its EspC serine protease motif, the direct cleavage of procaspase-3 being dependent on this motif. This is the first report showing a shortcut for induction of apoptosis by the catalytic activity of an EPEC protein. Furthermore, this atypical intrinsic apoptosis appeared to induce necrosis through the activation of calpain and through the increase of intracellular calcium induced by EspC. Our data indicate that EspC plays a relevant role in cell death induced by EPEC. PMID:27329750