Science.gov

Sample records for activation energies obtained

  1. Mechanism and activation energy of magnetic skyrmion annihilation obtained from minimum energy path calculations

    NASA Astrophysics Data System (ADS)

    Lobanov, Igor S.; Jónsson, Hannes; Uzdin, Valery M.

    2016-11-01

    The mechanism and activation energy for the annihilation of a magnetic skyrmion is studied by finding the minimum energy path for the transition in a system described by a Heisenberg-type Hamiltonian extended to include dipole-dipole, Dzyaloshinskii-Moriya, and anisotropy interactions so as to represent a Co monolayer on a Pt(111) surface. The annihilation mechanism involves isotropic shrinking of the skyrmion and slow increase of the energy until the transition state is reached after which the energy drops abruptly as the ferromagnetic final state forms. The maximum energy along the minimum energy path, which gives an estimate of the activation energy within the harmonic approximation of transition state theory, is found to be in excellent agreement with direct Langevin dynamics simulations at relatively high temperature carried out by Rohart et al. [Phys. Rev. B 93, 214412 (2016), 10.1103/PhysRevB.93.214412]. The dipole-dipole interaction, the computationally most demanding term in the Hamiltonian, is found to be important but its effect on the stability of the skyrmion and shape of the transition path can be mimicked accurately by reducing the anisotropy constant in the Hamiltonian.

  2. Measuring internal energy deposition in collisional activation using hydrated ion nanocalorimetry to obtain peptide dissociation energies and entropies.

    PubMed

    Demireva, Maria; Williams, Evan R

    2010-07-01

    The internal energy deposited in both on- and off-resonance collisional activation in Fourier transform ion cyclotron resonance mass spectrometry is measured with ion nanocalorimetry and is used to obtain information about the dissociation energy and entropy of a protonated peptide. Activation of Na(+)(H(2)O)(30) results in sequential loss of water molecules, and the internal energy of the activated ion can be obtained from the abundances of the product ions. Information about internal energy deposition in on-resonance collisional activation of protonated peptides is inferred from dissociation data obtained under identical conditions for hydrated ions that have similar m/z and degrees-of-freedom. From experimental internal energy deposition curves and Rice-Ramsperger-Kassel-Marcus (RRKM) theory, dissociation data as a function of collision energy for protonated leucine enkephalin, which has a comparable m/z and degrees-of-freedom as Na(+)(H(2)O)(30), are modeled. The threshold dissociation energies and entropies are correlated for data acquired at a single time point, resulting in a relatively wide range of threshold dissociation energies (1.1 to 1.7 eV) that can fit these data. However, this range of values could be significantly reduced by fitting data acquired at different dissociation times. By measuring the internal energy of an activated ion, the number of fitting parameters necessary to obtain information about the dissociation parameters by modeling these data is reduced and could result in improved accuracy for such methods.

  3. Energy savings obtainable through passive solar techniques

    SciTech Connect

    Balcomb, J.D.

    1980-01-01

    A passive solar energy system is one in which the thermal energy flow is by natural means, that is by radiation, conduction, or natural convection. The purpose of the paper is to provide a survey of passive solar heating experience, especially in the US. Design approaches are reviewed and examples shown. Misconceptions are discussed. Advantages are listed. The Los Alamos program of performance simulation and evaluation is described and a simplified method of performance estimation is outlined.

  4. Activation Energy

    NASA Technical Reports Server (NTRS)

    Gadeken, Owen

    2002-01-01

    Teaming is so common in today's project management environment that most of us assume it comes naturally. We further assume that when presented with meaningful and challenging work, project teams will naturally engage in productive activity to complete their tasks. This assumption is expressed in the simple (but false) equation: Team + Work = Teamwork. Although this equation appears simple and straightforward, it is far from true for most project organizations whose reality is a complex web of institutional norms based on individual achievement and rewards. This is illustrated by the very first successful team experience from my early Air Force career. As a young lieutenant, I was sent to Squadron Officer School, which was the first in the series of Air Force professional military education courses I was required to complete during my career. We were immediately formed into teams of twelve officers. Much of the course featured competition between these teams. As the most junior member of my team, I quickly observed the tremendous pressure to show individual leadership capability. At one point early in the course, almost everyone in our group was vying to become the team leader. This conflict was so intense that it caused us to fail miserably in our first outdoor team building exercise. We spent so much time fighting over leadership that we were unable to complete any of the events on the outdoor obstacle course. This complete lack of success was so disheartening to me that I gave our team little hope for future success. What followed was a very intense period of bickering, conflict, and even shouting matches as our dysfunctional team tried to cope with our early failures and find some way to succeed. British physician and researcher Wilfred Bion (Experiences in Groups, 1961) discovered that there are powerful psychological forces inherent in all groups that divert from accomplishing their primary tasks. To overcome these restraining forces and use the potential

  5. How Living Things Obtain Energy: A Simpler Explanation.

    ERIC Educational Resources Information Center

    Igelsrud, Donald E.

    1989-01-01

    Examines five basic reactions which describe the biochemical pathways for living things obtaining energy. Shows the reactions that occur in respiration after glycolysis, the dehydrogenation reaction, decarboxylation, and two kinds of make-ready reactions which prepare molecules for further dehydrogenation and decarboxylation. Diagrams are…

  6. Is it possible to obtain cosmic accelerated expansion through energy transfer between different energy densities?

    NASA Astrophysics Data System (ADS)

    Erdem, Recai

    2017-03-01

    The equation of state of an energy density may be significantly modified by coupling it to another energy density. In the light of this observation we check the possibility of producing cosmic accelerated expansion in this way. In particular we consider the case where matter is converted to radiation (or vice versa by particle physics processes). We find that cosmic accelerated expansion can be obtained in this way only if an intermediate state with negative equation of state forms during the conversion.

  7. Si film separation obtained by high energy proton implantation

    SciTech Connect

    Braley, C.; Mazen, F.; Papon, A.-M.; Rieutord, F.; Charvet, A.-M.; Ntsoenzok, E.

    2012-11-06

    High energy protons implantation in the 1-1.5 MeV range can be used to detach free-standing thin silicon films with thickness between 15 and 30 {mu}m. Recently, we showed that Si orientation has a strong effect on the layer separation threshold fluence and efficiency. While complete delamination of (111)Si films is achieved, (100)Si films separation is more challenging due to blistering phenomena or partial separation of the implanted layer. In this work, we study the fracture mechanism in (100) and (111)Si after high energy implantation in order to understand the origin of such a behavior. We notably point out that fracture precursor defects, i.e. the platelets, preferentially form on (111) planes, as a consequence of the low strain level in the damaged region in our implantation conditions. Fracture therefore propagates easily in (111)Si, while it requires higher fluence to overcome unfavorable precursors orientation and propagate in (100)Si.

  8. Science Activities in Energy: Chemical Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 15 activities relating to chemical energy. Activities are simple, concrete experiments for fourth, fifth and sixth grades which illustrate principles and problems relating to energy. Each activity is outlined on a single card which is introduced by a question. A teacher's…

  9. Science Activities in Energy: Solar Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 12 activities relating to solar energy. Activities are simple, concrete experiments for fourth, fifth, and sixth grades, which illustrate principles and problems relating to energy. Each activity is outlined on a single card which is introduced by a question. A teacher's supplement…

  10. Science Activities in Energy: Electrical Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 16 activities relating to electrical energy. Activities are simple, concrete experiments for fourth, fifth and sixth grades which illustrate principles and problems relating to energy. Each activity is outlined in a single card which is introduced by a question. A teacher's…

  11. Antifungal activity of silver nanoparticles obtained by green synthesis.

    PubMed

    Mallmann, Eduardo José J; Cunha, Francisco Afrânio; Castro, Bruno N M F; Maciel, Auberson Martins; Menezes, Everardo Albuquerque; Fechine, Pierre Basílio Almeida

    2015-01-01

    Silver nanoparticles (AgNPs) are metal structures at the nanoscale. AgNPs have exhibited antimicrobial activities against fungi and bacteria; however synthesis of AgNPs can generate toxic waste during the reaction process. Accordingly, new routes using non-toxic compounds have been researched. The proposal of the present study was to synthesize AgNPs using ribose as a reducing agent and sodium dodecyl sulfate (SDS) as a stabilizer. The antifungal activity of these particles against C. albicans and C. tropicalis was also evaluated. Stable nanoparticles 12.5 ± 4.9 nm (mean ± SD) in size were obtained, which showed high activity against Candida spp. and could represent an alternative for fungal infection treatment.

  12. ANTIFUNGAL ACTIVITY OF SILVER NANOPARTICLES OBTAINED BY GREEN SYNTHESIS

    PubMed Central

    MALLMANN, Eduardo José J.; CUNHA, Francisco Afrânio; CASTRO, Bruno N.M.F.; MACIEL, Auberson Martins; MENEZES, Everardo Albuquerque; FECHINE, Pierre Basílio Almeida

    2015-01-01

    Silver nanoparticles (AgNPs) are metal structures at the nanoscale. AgNPs have exhibited antimicrobial activities against fungi and bacteria; however synthesis of AgNPs can generate toxic waste during the reaction process. Accordingly, new routes using non-toxic compounds have been researched. The proposal of the present study was to synthesize AgNPs using ribose as a reducing agent and sodium dodecyl sulfate (SDS) as a stabilizer. The antifungal activity of these particles against C. albicans and C. tropicalis was also evaluated. Stable nanoparticles 12.5 ± 4.9 nm (mean ± SD) in size were obtained, which showed high activity against Candida spp. and could represent an alternative for fungal infection treatment. PMID:25923897

  13. Energy Model of Neuron Activation.

    PubMed

    Romanyshyn, Yuriy; Smerdov, Andriy; Petrytska, Svitlana

    2017-02-01

    On the basis of the neurophysiological strength-duration (amplitude-duration) curve of neuron activation (which relates the threshold amplitude of a rectangular current pulse of neuron activation to the pulse duration), as well as with the use of activation energy constraint (the threshold curve corresponds to the energy threshold of neuron activation by a rectangular current pulse), an energy model of neuron activation by a single current pulse has been constructed. The constructed model of activation, which determines its spectral properties, is a bandpass filter. Under the condition of minimum-phase feature of the neuron activation model, on the basis of Hilbert transform, the possibilities of phase-frequency response calculation from its amplitude-frequency response have been considered. Approximation to the amplitude-frequency response by the response of the Butterworth filter of the first order, as well as obtaining the pulse response corresponding to this approximation, give us the possibility of analyzing the efficiency of activating current pulses of various shapes, including analysis in accordance with the energy constraint.

  14. Changing Conceptions of Activation Energy.

    ERIC Educational Resources Information Center

    Pacey, Philip D.

    1981-01-01

    Provides background material which relates to the concept of activation energy, fundamental in the study of chemical kinetics. Compares the related concepts of the Arrhenius activation energy, the activation energy at absolute zero, the enthalpy of activation, and the threshold energy. (CS)

  15. Science Activities in Energy: Wind Energy.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Included in this science activities energy package are 12 activities related to wind energy for elementary students. Each activity is outlined on a single card and is introduced by a question. Topics include: (1) At what time of day is there enough wind to make electricity where you live?; (2) Where is the windiest spot on your schoolground?; and…

  16. Accurate Zero Parameter Correlation Energy Functional Obtained from the Homogeneous Electron Gas with an Energy Gap

    NASA Astrophysics Data System (ADS)

    Krieger, J. B.; Chen, Jiqiang; Iafrate, G. J.; Savin, A.

    1998-03-01

    We have obtained an analytic approximation to E_c(r_g, ζ,G) where G is an energy gap separating the occupied and unoccupied states of a homogeneous electron gas for ζ=3D0 and ξ=3D1. When G=3D0, E_c(r_g, ζ) reduces to the usual LSD result. This functional is employed in calculating correlation energies for unpolarized atoms and ions for Z <= 18 by taking G[n]=3D1/8|nabla ln n|^2, which reduces to the ionization energy in the large r limit in an exact Kohn-Sham (KS) theory. The resulting functional is self-interaction-corrected employing a method which is invariant under a unitary transformation. We find that the application of this approach to the calculation of the Ec functional reduces the error in the LSD result by more than 95%. When the value of G is approximately corrected to include the effect of higher lying unoccupied localized states, the resulting values of Ec are within a few percent of the exact results.

  17. 25 CFR 162.520 - Who owns the energy resource information obtained under the WEEL?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... AND WATER LEASES AND PERMITS Wind and Solar Resource Leases Weels § 162.520 Who owns the energy resource information obtained under the WEEL? (a) The WEEL must specify the ownership of any energy... 25 Indians 1 2013-04-01 2013-04-01 false Who owns the energy resource information obtained...

  18. 25 CFR 162.520 - Who owns the energy resource information obtained under the WEEL?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... AND WATER LEASES AND PERMITS Wind and Solar Resource Leases Weels § 162.520 Who owns the energy resource information obtained under the WEEL? (a) The WEEL must specify the ownership of any energy... 25 Indians 1 2014-04-01 2014-04-01 false Who owns the energy resource information obtained...

  19. Activities Handbook for Energy Education.

    ERIC Educational Resources Information Center

    DeVito, Alfred; Krockover, Gerald H.

    The purpose of this handbook is to present information about energy and to translate this information into learning activities for children. Chapter 1, "Energy: A Delicate Dilemma," presents activities intended to provide an introduction to energy and energy usage. Chapter 2, "What are the Sources of Energy?" provides…

  20. Energy Adventure Center. Activity Book.

    ERIC Educational Resources Information Center

    Carlton, Linda L.

    Energy activities are provided in this student activity book. They include: (1) an energy walk; (2) forms of energy in the home; (3) energy conversion; (4) constructing a solar hot dog cooker (with instructions for drawing a parabola); (5) interviewing senior citizens to learn about energy use in the past; (6) packaging materials; (7) insulation;…

  1. Science Activities in Energy: Conservation.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 14 activities relating to energy conservation. Activities are simple, concrete experiments for fourth, fifth and sixth grades, which illustrate principles and problems relating to energy. Each activity is outlined on a simple card which is introduced by a question. A teacher's…

  2. Science Activities in Energy: Solar Energy II.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Included in this science activities energy package are 14 activities related to solar energy for secondary students. Each activity is outlined on a single card and is introduced by a question such as: (1) how much solar heat comes from the sun? or (2) how many times do you have to run water through a flat-plate collector to get a 10 degree rise in…

  3. Synthesis and antiviral activity of azoles obtained from carbohydrates.

    PubMed

    Barradas, José Sebastián; Errea, María Inés; D'Accorso, Norma B; Sepúlveda, Claudia S; Talarico, Laura B; Damonte, Elsa B

    2008-09-22

    Herein we describe the synthesis of 1,2,4-triazolyl-3-thione;1,3,4-oxadiazole, and imidazo[2,1-b]thiazole derivatives from carbohydrates. The antiviral activity of these compounds was tested against Dengue and Junin virus (the etiological agent of Argentine hemorrhagic fever). The 3-(p-bromobenzoyl)-5-(1,2-O-isopropylidene-3-O-methyl-alpha-d-xylofuranos-5-ulos-5-yl)imidazo[2,1-b]thiazole was able to inhibit the replication of both viruses in Vero cells at concentration significantly lower than the CC(50).

  4. Solar Energy Education. Renewable energy activities for earth science

    SciTech Connect

    Not Available

    1980-01-01

    A teaching manual is provided to aid teachers in introducing renewable energy topics to earth science students. The main emphasis is placed on solar energy. Activities for the student include a study of the greenhouse effect, solar gain for home heating, measuring solar radiation, and the construction of a model solar still to obtain fresh water. Instructions for the construction of apparatus to demonstrate a solar still, the greenhouse effect and measurement of the altitude and azimuth of the sun are included. (BCS)

  5. Energy dependence of hadronic activity

    NASA Astrophysics Data System (ADS)

    Gabriel, T. A.; Groom, D. E.; Job, P. K.; Mokhov, N. V.; Stevenson, G. R.

    1994-01-01

    Two features of high-energy hadronic cascades have long been known to shielding specialists: a) in a high-energy hadronic cascade in a given material (incident E ≳ 10 GeV), the relative abundance and spectrum of each hadronic species responsible for most of the energy deposition is independent of the energy or species of the incident hadron, and b) because π0 production bleeds off more and more energy into the electromagnetic sector as the energy of the incident hadron increases, the absolute level of this low-energy hadronic activity ( E ≲ 1 GeV) rises less rapidly than the incident energy, and in fact rises very nearly as a power of the incident energy. Both features are of great importance in hadron calorimetry, where it is the "universal spectrum" which makes possible the definition of an intrinsic {e}/{h}, and the increasing fraction of the energy going into π0's which leads to the energy dependence of {e}/{π}. We present evidence for the "universal spectrum," and use an induction argument and simulation results to demonstrate that the low-energy activity ss Em, with 0.80 ≲ m ≲ 0.85. The hadronic activity produced by incident pions is 15-20% less than that initiated by protons.

  6. Energy distribution of the particles obtained after irradiation of carbon nanotubes with carbon projectiles

    NASA Astrophysics Data System (ADS)

    Denton, Cristian D.; Moreno-Marín, Juan Carlos; Heredia-Avalos, Santiago

    2015-06-01

    The idea of using carbon nanotubes (CNTs) as masks against irradiation has recently emerged, because of the region of a given material covered by a CNT can be protected from the effects of irradiation, creating nanowires. In this case, it is interesting to know in detail the number of generated recoils and their energy. In order to obtain these data, we simulate the irradiation of CNTs with carbon ions using a molecular dynamics code. To describe the interaction between carbon ions we use the Brenner potential joined smoothly to the Universal ZBL potential at short distances. We have analyzed the energy distributions of the carbon atoms emerging from the CNT for single projectile irradiation with incident energies from 30 eV to 5 keV. Our results show that the number and the energy of the recoil carbon atoms emerging from the CNT increases with the projectile incident energy. In average, each projectile with incident energy of 1 keV produces ∼3.6 recoils, which have a mean energy of 150 eV, while projectiles with 5 keV produce ∼7 recoils with a mean energy of 400 eV.

  7. Energy parameters of precipitating auroral electrons obtained by using photometric observations

    SciTech Connect

    Ono, Takayuki; Morishima, Kei )

    1994-02-15

    The authors present a ground based photometric method for measuring both the average energy and total energy flux for active discrete auroras. They make use of a multichannel photometer, with a narrow field of view. They monitor auroral emissions from atomic states and molecular bands, and by determining intensity ratios, are able to infer information relative to energy parameters of precipitating electrons in discrete arcs. They are able to look along magnetic axes. One observation is that there is a relationship between the energy flux and average energy, which can be considered ohmic in character, consistent with a model that precipitating electrons are accelerated along field lines by potential differences which can exist along these field lines.

  8. Efficient approach to obtain free energy gradient using QM/MM MD simulation

    SciTech Connect

    Asada, Toshio; Koseki, Shiro; Ando, Kanta

    2015-12-31

    The efficient computational approach denoted as charge and atom dipole response kernel (CDRK) model to consider polarization effects of the quantum mechanical (QM) region is described using the charge response and the atom dipole response kernels for free energy gradient (FEG) calculations in the quantum mechanical/molecular mechanical (QM/MM) method. CDRK model can reasonably reproduce energies and also energy gradients of QM and MM atoms obtained by expensive QM/MM calculations in a drastically reduced computational time. This model is applied on the acylation reaction in hydrated trypsin-BPTI complex to optimize the reaction path on the free energy surface by means of FEG and the nudged elastic band (NEB) method.

  9. A quantum algorithm for obtaining the energy spectrum of a physical system without guessing its eigenstates.

    PubMed

    Wang, Hefeng

    2014-08-14

    We present a quantum algorithm that provides a general approach for obtaining the energy spectrum of a physical system without making a guess on its eigenstates. In this algorithm, a probe qubit is coupled to a quantum register R which consists of one ancilla qubit and an n-qubit register that represents the system. R is prepared in a general reference state, and a general excitation operator that acts on R is constructed. The probe exhibits a dynamical response only when it is resonant with a transition from the reference state to an excited state of R which contains the eigenstates of the system. By varying the probe's frequency, the energy spectrum and the eigenstates of the system can be obtained.

  10. Iterative methods for obtaining energy-minimizing parametric snakes with applications to medical imaging.

    PubMed

    Mitrea, Alexandru Ioan; Badea, Radu; Mitrea, Delia; Nedevschi, Sergiu; Mitrea, Paulina; Ivan, Dumitru Mircea; Gurzău, Octavian Mircia

    2012-01-01

    After a brief survey on the parametric deformable models, we develop an iterative method based on the finite difference schemes in order to obtain energy-minimizing snakes. We estimate the approximation error, the residue, and the truncature error related to the corresponding algorithm, then we discuss its convergence, consistency, and stability. Some aspects regarding the prosthetic sugical methods that implement the above numerical methods are also pointed out.

  11. Converging ligand-binding free energies obtained with free-energy perturbations at the quantum mechanical level.

    PubMed

    Olsson, Martin A; Söderhjelm, Pär; Ryde, Ulf

    2016-06-30

    In this article, the convergence of quantum mechanical (QM) free-energy simulations based on molecular dynamics simulations at the molecular mechanics (MM) level has been investigated. We have estimated relative free energies for the binding of nine cyclic carboxylate ligands to the octa-acid deep-cavity host, including the host, the ligand, and all water molecules within 4.5 Å of the ligand in the QM calculations (158-224 atoms). We use single-step exponential averaging (ssEA) and the non-Boltzmann Bennett acceptance ratio (NBB) methods to estimate QM/MM free energy with the semi-empirical PM6-DH2X method, both based on interaction energies. We show that ssEA with cumulant expansion gives a better convergence and uses half as many QM calculations as NBB, although the two methods give consistent results. With 720,000 QM calculations per transformation, QM/MM free-energy estimates with a precision of 1 kJ/mol can be obtained for all eight relative energies with ssEA, showing that this approach can be used to calculate converged QM/MM binding free energies for realistic systems and large QM partitions. © 2016 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc.

  12. Simulation of motions of the plasma in a fusion reactor for obtaining of future energy

    NASA Astrophysics Data System (ADS)

    Zhumabekov, Askhat

    2017-01-01

    According to the most conservative estimates, by the middle of the XXI century in the world energy consumption will double. This will be a consequence of the global economic development, population growth and other geopolitical and economic factors. Energy consumption in the world is growing much faster than its production and industrial use of new advanced technologies in the energy sector, for objective reasons, will not begin until 2030. This paper discusses how to obtain and develop nuclear energy on the experience of the National Nuclear Center. Implemented model for the problem of plasma confinement, and also presents the main achievements of modern construction and Megaproject National Nuclear Center in Kurchatov, the Republic of Kazakhstan. Spend a social survey in the East Kazakhstan region on the theme: “Prospects for the development of nuclear energy in Kazakhstan” and the citizens’ opinion. Narration new priorities for May 22, 2015 in Ust-Kamenogorsk in the industrial park “Altai” based on the competition of innovation projects green technology in the international exhibition “OSKEMEN EXPO – 2015”, with the participation of the regional authorities of the Republic of Kazakhstan, representatives of JSC NC “Astana Expo” and delegations from Japan, Russia, Canada, USA, South Korea.

  13. ACE-I Inhibitory Activity from Phaseolus lunatus and Phaseolus vulgaris Peptide Fractions Obtained by Ultrafiltration.

    PubMed

    Betancur-Ancona, David; Dávila-Ortiz, Gloria; Chel-Guerrero, Luis Antonio; Torruco-Uco, Juan Gabriel

    2015-11-01

    The involvement of angiotensin-I-converting enzyme (ACE-I) as one of the mechanisms controlling blood pressure is being studied to find alternative means of control of hypertension on human beings. On the market there are synthetic drugs that can control it, but these can cause undesirable health side effects. In this work was assessed the fractionation by ultrafiltration of the Lima bean (Phaseolus lunatus) and Jamapa bean (Phaseolus vulgaris), protein hydrolysates obtained with Alcalase(®) and Flavourzyme(®) on ACE-I inhibitory activity. Four membranes of different molecular cutoffs (10, 5, 3, and 1 kDa) were used. Fractions that had a higher inhibitory activity in both legumes were denominated as E (<1 kDa) with IC50 of 30.3 and 51.8 μg/mL values for the P. lunatus with Alcalase and Flavourzyme, respectively, and for the Phaseolus vulgaris with Alcalase and Flavourzyme with about 63.8 and 65.8 μg/mL values, respectively. The amino acid composition of these fractions showed residues in essential amino acids, which make a good source of energy and amino acids. On the other hand, the presence of hydrophobic amino acids such as V and P is a determining factor in the ACE-I inhibitor effect. The results suggest the possibility of obtaining and utilizing these peptide fractions in the development and innovation of a functional product that helps with treatment and/or prevention of hypertension.

  14. Solar Energy Project, Activities: Biology.

    ERIC Educational Resources Information Center

    Tullock, Bruce, Ed.; And Others

    This guide contains lesson plans and outlines of science activities which present concepts of solar energy in the context of biology experiments. Each unit presents an introduction; objectives; skills and knowledge needed; materials; methods; questions; recommendations for further work; and a teacher information sheet. The teacher information…

  15. Activation energy measurements of cheese

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Temperature sweeps of cheeses using small amplitude oscillatory shear tests produced values for activation energy of flow (Ea) between 30 and 44 deg C. Soft goat cheese and Queso Fresco, which are high-moisture cheeses and do not flow when heated, exhibited Ea values between 30 and 60 kJ/mol. The ...

  16. 10 CFR 708.35 - How can a party obtain review by the Secretary of Energy of an appeal decision?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false How can a party obtain review by the Secretary of Energy of an appeal decision? 708.35 Section 708.35 Energy DEPARTMENT OF ENERGY DOE CONTRACTOR EMPLOYEE PROTECTION PROGRAM Investigation, Hearing and Decision Process § 708.35 How can a party obtain review by the Secretary of Energy of an appeal decision?...

  17. Edge-enhanced imaging obtained with very broad energy band x-rays

    SciTech Connect

    Taibi, A.; Cardarelli, P.; Di Domenico, G.; Marziani, M.; Gambaccini, M.; Hanashima, T.; Yamada, H.

    2010-04-05

    We demonstrate both theoretically and experimentally that edge-enhancement effects are produced when objects, in contact with the x-ray detector, are imaged by using very broad x-ray spectra. Radiographs of thin Al objects have been obtained with a table-top synchrotron source which generates x-rays in the energy range from a few kilo-electron-volts up to 6 MeV. Edge-enhancement effects arise from the combination of x-ray absorption (kilo-electron-volt part of the spectrum) and secondary particle emission (mega-electron-volt part of the spectrum) within the sample. The exact contribution of absorption and emission profiles in the edge-enhanced images has been calculated via Monte Carlo simulation.

  18. Optimization of synthesis and peptization steps to obtain iron oxide nanoparticles with high energy dissipation rates

    PubMed Central

    Mérida, Fernando; Chiu-Lam, Andreina; Bohórquez, Ana C.; Maldonado-Camargo, Lorena; Pérez, María-Eglée; Pericchi, Luis; Torres-Lugo, Madeline; Rinaldi, Carlos

    2015-01-01

    Magnetic Fluid Hyperthermia (MFH) uses heat generated by magnetic nanoparticles exposed to alternating magnetic fields to cause a temperature increase in tumors to the hyperthermia range (43–47 °C), inducing apoptotic cancer cell death. As with all cancer nanomedicines, one of the most significant challenges with MFH is achieving high nanoparticle accumulation at the tumor site. This motivates development of synthesis strategies that maximize the rate of energy dissipation of iron oxide magnetic nanoparticles, preferable due to their intrinsic biocompatibility. This has led to development of synthesis strategies that, although attractive from the point of view of chemical elegance, may not be suitable for scale-up to quantities necessary for clinical use. On the other hand, to date the aqueous co-precipitation synthesis, which readily yields gram quantities of nanoparticles, has only been reported to yield sufficiently high specific absorption rates after laborious size selective fractionation. This work focuses on improvements to the aqueous co-precipitation of iron oxide nanoparticles to increase the specific absorption rate (SAR), by optimizing synthesis conditions and the subsequent peptization step. Heating efficiencies up to 1,048 W/gFe (36.5 kA/m, 341 kHz; ILP = 2.3 nH·m2·kg−1) were obtained, which represent one of the highest values reported for iron oxide particles synthesized by co-precipitation without size-selective fractionation. Furthermore, particles reached SAR values of up to 719 W/gFe (36.5 kA/m, 341 kHz; ILP = 1.6 nH·m2·kg−1) when in a solid matrix, demonstrating they were capable of significant rates of energy dissipation even when restricted from physical rotation. Reduction in energy dissipation rate due to immobilization has been identified as an obstacle to clinical translation of MFH. Hence, particles obtained with the conditions reported here have great potential for application in nanoscale thermal cancer therapy. PMID:26273124

  19. Energy Activities for the Primary Classroom. Revised.

    ERIC Educational Resources Information Center

    Tierney, Blue, Comp.

    An energy education program at the primary level should help students to understand the nature and importance of energy, consider different energy sources, learn about energy conservation, prepare for energy related careers, and become energy conscious in other career fields. The activities charts, readings, and experiments provided in this…

  20. Energy Storage. Teachers Guide. Science Activities in Energy.

    ERIC Educational Resources Information Center

    Jacobs, Mary Lynn, Ed.

    Included in this science activities energy package for students in grades 4-10 are 12 activities related to energy storage. Each activity is outlined on the front and back of a single sheet and is introduced by a key question. Most of the activities can be completed in the classroom with materials readily available in any community. Among the…

  1. Cytostatic activity of some compounds from the unsaponifiable fraction obtained from virgin olive oil.

    PubMed

    Saenz, M T; Garcia, M D; Ahumada, M C; Ruiz, V

    1998-06-30

    Oleuropein, tyrosol, squalene and the fraction of sterols and triterpenoid dialcohols from the unsaponifiable fraction obtained from virgin olive oil have been tested for possible cytostatic activity against McCoy cells, using 6-mercaptopurine as a positive control. The samples of sterols and triterpenic dialcohols showed a strong activity.

  2. Activated carbon from char obtained from vacuum pyrolysis of teak sawdust: pore structure development and characterization.

    PubMed

    Ismadji, S; Sudaryanto, Y; Hartono, S B; Setiawan, L E K; Ayucitra, A

    2005-08-01

    The preparation of activated carbon from vacuum pyrolysis char of teak sawdust was studied and the results are presented in this paper. The effects of process variables such as temperature and activation time on the pore structure of activated carbons were studied. The activated carbon prepared from char obtained by vacuum pyrolysis has higher surface area and pore volume than that from atmospheric pyrolysis char. The BET surface area and pore volume of activated carbon prepared from vacuum pyrolysis char were 1150 m2/g and 0.43 cm3/g, respectively.

  3. [Biological activity of electrochemically activated solutions obtained in a diaphragm electrolyser].

    PubMed

    Miroshnikov, A I; Konovalov, V F; Serikov, I S

    2006-01-01

    The biological activity of the catholyte and anolyte of bidistilled water in experiments with the germination of wheat grains in the period from March to May has been studied. The activity of solutions, which was characterized by the grain germination index, was high at the beginning of the period, then it gradually decreased and was equal to zero at the middle of the period; at the end of the period it gradually increased almost to initial values. It has been established that the effectiveness of bidistilled water anolyte was as a rule higher than that of catholyte throughout the observation period. At the beginning and end, the stimulating effect of anolyte was 5-5.5 times greater than that of catholyte. The seasonal changes in the biological activity of M 9 medium catholyte were compared with those of bidistilled water anolyte and catholyte. The stimulating effect of M 9 catholyte was estimated by changes in the growth of E. coli cells. The stimulating effect, which was estimated from an increase in the optical density of cell suspension in the initial period at a cultivation temperature of 20 degrees C was 55-60% relative to control (untreated medium). Then it decreased almost to zero in the middle of the period to increase again approximately to the initial values. The assumption has been made that the physicochemical causes of the influence of catholyte and anolyte of bidistilled water on wheat grains and of the culture medium catholyte on E. coli cells are of different nature.

  4. Dataset of the AAC2 conformations in the c-, intermediate- and m-states obtained from free-energy simulations

    PubMed Central

    Pietropaolo, Adriana; Pierri, Ciro Leonardo; Palmieri, Ferdinando; Klingenberg, Martin

    2016-01-01

    The data reported herein are related to the article entitled: “The switching mechanism of the mitochondrial ADP/ATP carrier explored by free-energy landscapes” (Pietropaolo et al., 2016) [1]. We report the coordinates of the ADP/ATP carrier (AAC2) in the presence and absence of adenine and guanine nucleotides in the c-, intermediate- and m-states obtained from the free-energy simulations and corresponding to the free-energy minima. PMID:27158649

  5. Solar Energy Education. Renewable energy activities for biology

    SciTech Connect

    Not Available

    1982-01-01

    An instructional aid for teachers is presented that will allow biology students the opportunity to learn about renewable energy sources. Some of the school activities include using leaves as collectors of solar energy, solar energy stored in wood, and a fuel value test for green and dry woods. A study of organic wastes as a source of fuel is included. (BCS)

  6. Solar energy education. Renewable energy activities for general science

    SciTech Connect

    Not Available

    1985-01-01

    Renewable energy topics are integrated with the study of general science. The literature is provided in the form of a teaching manual and includes such topics as passive solar homes, siting a home for solar energy, and wind power for the home. Other energy topics are explored through library research activities. (BCS)

  7. Energy-efficiency testing activities of the Mobile Energy Laboratory

    SciTech Connect

    Parker, G.B.

    1991-01-01

    This report summarizes energy-efficiency testing activities during the first and second quarters of fiscal year 1990 applying the Mobile Energy Laboratory (MEL) testing capabilities. Four MELs, developed by the US Department of Energy (DOE) Federal Energy Management Program (FEMP), are administered by Pacific Northwest Laboratory (PNL) for energy testing and program support functions at federal facilities. The using agencies principally fund MEL applications, while DOE/FEMP funds program administration and capability enhancement activities. This report fulfills the requirements established in the MEL Use Plan (PNL-6861) for semiannual reporting on energy-efficiency testing activities using the MEL capabilities. The MEL Use Committee, formally established in 1989, developed the MEL Use Plan and meets semiannually to establish priorities for energy-efficient testing applications using the MEL capabilities.

  8. Energy Activities for Junior High Science.

    ERIC Educational Resources Information Center

    Beaver, David; And Others

    This document is a collection of six energy education activities for junior high school science. Its purpose is to help promote knowledge about energy, provide laboratory experiences, provoke inquiry, and relate energy to society through the science curriculum. The six activities are designed to take one to three class periods. Two of the…

  9. Nuclear mass formula with the shell energies obtained by a new method

    SciTech Connect

    Koura, H.; Tachibana, T.; Yamada, M.; Uno, M.

    1998-12-21

    Nuclear shapes and masses are estimated by a new method. The main feature of this method lies in estimating shell energies of deformed nuclei from spherical shell energies by mixing them with appropriate weights. The spherical shell energies are calculated from single-particle potentials, and, till now, two mass formulas have been constructed from two different sets of potential parameters. The standard deviation of the calculated masses from all the experimental masses of the 1995 Mass Evaluation is about 760 keV. Contrary to the mass formula by Tachibana, Uno, Yamada and Yamada in the 1987-1988 Atomic Mass Predictions, the present formulas can give nuclear shapes and predict on super-heavy elements.

  10. Obtaining a Dry Extract from the Mikania laevigata Leaves with Potential for Antiulcer Activity

    PubMed Central

    Pinto, Mariana Viana; Oliveira, Ezequiane Machado; Martins, Jose Luiz Rodrigues; de Paula, Jose Realino; Costa, Elson Alves; da Conceição, Edemilson Cardoso; Bara, Maria Teresa Freitas

    2017-01-01

    Background: Mikania laevigata leaves are commonly used in Brazil as a medicinal plant. Objective: To obtain hydroalcoholic dried extract by nebulization and evaluate its antiulcerogenic potential. Materials and Methods: Plant material and hydroalcoholic extract were processed and analyzed for their physicochemical characteristics. A method using HPLC was validated to quantify coumarin and o-coumaric acid. Hydroalcoholic extract was spray dried and the powder obtained was characterized in terms of its physicochemical parameters and potential for antiulcerogenic activity. Results: The analytical method proved to be selective, linear, precise, accurate, sensitive, and robust. M. laevigata spray dried extract was obtained using colloidal silicon dioxide as adjuvant and was shown to possess 1.83 ± 0.004% coumarin and 0.80 ± 0.012% o-coumaric acid. It showed significant antiulcer activity in a model of an indomethacin-induced gastric lesion in mice and also produced a gastroprotective effect. Conclusion: This dried extract from M. laevigata could be a promising intermediate phytopharmaceutical product. SUMMARY Research and development of standardized dried extract of Mikania laevigata leaves obtained through spray drying and the production process was monitored by the chemical profile, physicochemical properties and potential for anti-ulcerogenic activity. Abbreviations used: DE: M. laevigata spray dried extract, HE: hydroalcoholic extract. PMID:28216886

  11. Influence of process parameters on the surface and chemical properties of activated carbon obtained from biochar by chemical activation.

    PubMed

    Angın, Dilek; Altintig, Esra; Köse, Tijen Ennil

    2013-11-01

    Activated carbons were produced from biochar obtained through pyrolysis of safflower seed press cake by chemical activation with zinc chloride. The influences of process variables such as the activation temperature and the impregnation ratio on textural and chemical-surface properties of the activated carbons were investigated. Also, the adsorptive properties of activated carbons were tested using methylene blue dye as the targeted adsorbate. The experimental data indicated that the adsorption isotherms are well described by the Langmuir equilibrium isotherm equation. The optimum conditions resulted in activated carbon with a monolayer adsorption capacity of 128.21 mg g(-1) and carbon content 76.29%, while the BET surface area and total pore volume corresponded to 801.5m(2)g(-1) and 0.393 cm(3)g(-1), respectively. This study demonstrated that high surface area activated carbons can be prepared from the chemical activation of biochar with zinc chloride as activating agents.

  12. Operant behavior to obtain palatable food modifies ERK activity in the brain reward circuit.

    PubMed

    Guegan, Thomas; Cutando, Laura; Gangarossa, Giuseppe; Santini, Emanuela; Fisone, Gilberto; Martinez, Albert; Valjent, Emmanuel; Maldonado, Rafael; Martin, Miquel

    2013-03-01

    Food palatability produces behavioral modifications that resemble those induced by drugs of abuse. Palatability-induced behavioral changes require both, the activation of the endogenous cannabinoid system, and changes in structural plasticity in neurons of the brain reward pathway. The ERK intracellular pathway is activated by CB1 receptors (CB1-R) and plays a crucial role in neuroplasticity. We investigated the activation of the ERK signaling cascade in the mesocorticolimbic system induced by operant training to obtain highly palatable isocaloric food and the involvement of the CB1-R in these responses. Using immunofluorescence techniques, we analyzed changes in ERK intracellular pathway activation in the mesocorticolimbic system of wild-type and CB1 knockout mice (CB1-/-) trained on an operant paradigm to obtain standard, highly caloric or highly palatable isocaloric food. Operant training for highly palatable isocaloric food, but not for standard or highly caloric food, produced a robust activation of the ERK signaling cascade in the same brain areas where this training modified structural plasticity. These changes induced by the operant training were absent in CB1-/-. We can conclude that the activation of the ERK pathway is associated to the neuroplasticity induced by operant training for highly palatable isocaloric food and might be involved in CB1-R mediated alterations in behavior and structural plasticity.

  13. Use of grape stalk, a waste of the viticulture industry, to obtain activated carbon.

    PubMed

    Deiana, A C; Sardella, M F; Silva, H; Amaya, A; Tancredi, N

    2009-12-15

    Grape stalk is an organic waste produced in great amounts in the industrialization processes of grape. This work presents the results of studies carried out to use this waste as raw material to prepare activated carbon through the physical and chemical route. The physicochemical characterization of this material suggests the presence of unusually high levels of ashes. Metal content was determined and high levels of potassium, sodium, iron, calcium and magnesium in carbonized and raw grape stalk were exhibited. This characteristic made difficult physical activation at high temperatures. A leaching step was included before the activation with steam, and adsorbents with surface areas between 700 and 900 m(2)/g were obtained. Physical activation was also performed at lower temperatures using carbonized grape stalk without leaching, leading to the development of some grade of porosity, with an area of 412 m(2)/g. These results would indicate the catalytic effect of the minerals present in this raw material. Chemical activation using phosphoric acid as activating agent seemed to be a very efficient method as final products with BET areas between 1000 and 1500 m(2)/g were obtained.

  14. Antimicrobial activity and composition profile of grape (Vitis vinifera) pomace extracts obtained by supercritical fluids.

    PubMed

    Oliveira, Daniela A; Salvador, Ana Augusta; Smânia, Artur; Smânia, Elza F A; Maraschin, Marcelo; Ferreira, Sandra R S

    2013-04-10

    The possibility of increasing the aggregated value of the huge amount of residues generated by wineries around the world foment studies using the grape pomace - the residue from the wine production, composed by seed, skin and stems - to obtain functional ingredients. Nowadays, consumers in general prefer natural and safe products mainly for food and cosmetic fields, where the supercritical fluid extraction is of great importance due to the purity of the extracts provided. Therefore, the objective of this work is to evaluate the global extraction yield, the antimicrobial activity and the composition profile of Merlot and Syrah grape pomace extracts obtained by supercritical CO2 (SC-CO2) and CO2 added with co-solvent at pressures up to 300 bar and temperatures of 50 and 60 °C. The results were compared with the ones obtained by Soxhlet and by ultrasound-assisted leaching extraction methods. The main components from the extracts, identified by HPLC, were gallic acid, p-OH-benzoic acid, vanillic acid and epicatechin. The antibacterial and antifungal activities of the extracts were evaluated using four strains of bacteria (Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa) and three fungi strains (Candida albicans, Candida parapsilosis, Candida krusei). Despite lower extraction yield results, the supercritical fluid extracts presented the highest antimicrobial effectiveness compared to the other grape pomace extracts due to the presence of antimicrobial active compounds. Syrah extracts were less efficient against the microorganisms tested and Merlot extracts were more active against Gram-positive bacteria.

  15. Antimicrobial activity of Anonna mucosa (Jacq.) grown in vivo and obtained by in vitroculture

    PubMed Central

    de Souza Barboza, Thiago José; Ferreira, Andréa Fonseca; de Paula Rosa Ignacio, Ana Claudia; Albarello, Norma

    2015-01-01

    Brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. Plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. Annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. The widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. In view of this problem, the aim of this work was to evaluate the antibacterial potential of extracts of A. mucosa obtained by in vitro techniques and also cultured under in vivo conditions. Segments from seedlings were inoculated onto different culture media containing the auxin picloram and the cytokinin kinetin at different concentrations. The calluses obtained were used to produce cell suspension cultures. The materials were subjected to methanol extraction and subsequent fractionation in hexane and dichloromethane. The antimicrobial activity against 20 strains of clinical relevance was evaluated by the macrodilution method at minimum inhibitory and minimum bactericidal concentrations. The extracts showed selective antimicrobial activity, inhibiting the growth of Streptococcus pyogenes and Bacillus thuringiensis at different concentrations. The plant tissue culture methods produced plant materials with antibacterial properties, as well as in vivo grown plants. The antibacterial activity of material obtained through biotechnological procedures of A. mucosa is reported here for the first time. PMID:26413061

  16. Process for obtaining energy, soft water and by-products from aqueous substances

    SciTech Connect

    Grenet, E.P.

    1982-08-17

    The aqueous substance, for example sea water, is boiled, the steam produced is fed under pressure into a turbo-alternator turbine producing electricity, the residual steam is reduced into soft water and the residue of evaporation, for example sea salt, is recovered as a by-product. The steam is fed directly or on leaving the turbine onto iron heated to about 800* C., which supplies hydrogen and as a byproduct ferric oxide. The initial source of energy is, besides solar energy, any known source of energy, such as coal situated at great depths. The starting aqueous substance is, apart from sea water, waste sludges, a rock salt solution or a mixture of sludges and salt solution. In the case of sludges, the by-product is a dry and sterilized fertilizer transformable into fuel bricks. The salt residue is transformable by electrolysis into hydrogen and sodium chlorate, which is a fuel. The sludge-salt residue supplies a combustible mixture. Dried sludges-sodium chlorate, is mixable with household waste for promoting the combustibility thereof. The sodium chlorate can be transformed into potassium chlorate and the steam under pressure may be condensed in distant reservoirs and its heat recovered. The energies produced in the turbo alternator or fuel-by products are usable in the process.

  17. Use of Different Proteases to Obtain Flaxseed Protein Hydrolysates with Antioxidant Activity

    PubMed Central

    Karamać, Magdalena; Kosińska-Cagnazzo, Agnieszka; Kulczyk, Anna

    2016-01-01

    The antioxidant activity of flaxseed protein hydrolysates obtained using five different enzymes was evaluated. Proteins were isolated from flaxseed cake and were separately treated with papain, trypsin, pancreatin, Alcalase and Flavourzyme. The degree of hydrolysis (DH) was determined as the percentage of cleaved peptide bonds using a spectrophotometric method with o-phthaldialdehyde. The distribution of the molecular weights (MW) of the hydrolysis products was profiled using Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine-SDS-PAGE) and size exclusion-high performance liquid chromatography (SE-HPLC) separations. The antioxidant activities of the protein isolate and hydrolysates were probed for their radical scavenging activity using 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonate) radical cation (ABTS•+) and photochemiluminescence (PCL-ACL) assays, and for their ferric reducing antioxidant power (FRAP) and ability to bind Fe2+. The hydrolysates were more effective as antioxidants than the protein isolate in all systems. The PCL-ACL values of the hydrolysates ranged from 7.2 to 35.7 μmol Trolox/g. Both the FRAP and ABTS•+ scavenging activity differed among the hydrolysates to a lower extent, with the ranges of 0.20–0.24 mmol Fe2+/g and 0.17–0.22 mmol Trolox/g, respectively. The highest chelating activity (71.5%) was noted for the pancreatin hydrolysate. In general, the hydrolysates obtained using Alcalase and pancreatin had the highest antioxidant activity, even though their DH (15.4% and 29.3%, respectively) and the MW profiles of the peptides varied substantially. The O2•− scavenging activity and the ability to chelate Fe2+ of the Flavourzyme hydrolysate were lower than those of the Alcalase and pancreatin hydrolysates. Papain was the least effective in releasing the peptides with antioxidant activity. The study showed that the type of enzyme used for flaxseed protein hydrolysis determines the antioxidant activity of

  18. Energy Conservation Activity Packet, Grade 5.

    ERIC Educational Resources Information Center

    Bakke, Ruth

    This activity packet for grade 5 is one of a series developed in response to concern for energy conservation. It contains activities that stress an energy conservation ethic and includes many values clarification activities for grade five. The packet is divided into two parts and provides the teacher with background information, concepts and…

  19. Antiproliferative Activity of Polyether Antibiotic--Cinchona Alkaloid Conjugates Obtained via Click Chemistry.

    PubMed

    Skiera, Iwona; Antoszczak, Michał; Trynda, Justyna; Wietrzyk, Joanna; Boratyński, Przemysław; Kacprzak, Karol; Huczyński, Adam

    2015-10-01

    A series of eight new conjugates of salinomycin or monensin and Cinchona alkaloids were obtained by the Cu(I)-catalysed 1,3-dipolar Huisgen cycloaddition (click chemistry) of respective N-propargyl amides of salinomycin or monensin with four different Cinchona alkaloid derived azides. In vitro antiproliferative activity of these conjugates evaluated against three cancer cell lines (LoVo, LoVo/DX, HepG2) showed that four of the compounds exhibited high antiproliferative activity (IC50 below 3.00 μm) and appeared to be less toxic and more selective against normal cells than two standard anticancer drugs.

  20. Evaluation of anti-cancer activity of Acanthester planci extracts obtained by different methods of extraction.

    PubMed

    Mutee, Ahmed Faisal; Salhimi, Salizawati Muhamad; Ghazali, Farid Che; Aisha, Abdalrahim Fa; Lim, Chung Pin; Ibrahim, Kamarruddin; Asmawi, Mohd Zaini

    2012-10-01

    Acanthaster planci, the crown-of-thorns starfish, naturally endowed with the numerous toxic spines around the dorsal area of its body. Scientific investigations demonstrated several toxico-pharmacological efficacies of A. planci such as, myonecrotic activity, hemorrhagic activity, hemolytic activity, mouse lethality, phospholipase A2 (PLA2) activity, capillary permeability-increasing activity, edema-forming activity, anticoagulant activity and histamine-releasing activity from mast cells. The present study was performed to evaluate the cytotoxic activity of A. planci extracts obtained by different methods of extraction on MCF-7 and HCT-116, human breast and colon cancer cell lines, respectively. Results of the cell proliferation assay showed that PBS extract exhibited very potent cytotoxic activity against both MCF-7 and HCT-116 cell lines with IC(50) of 13.48 μg/mL and 28.78 μg/mL, respectively, while the extracts prepared by Bligh and Dyer method showed moderate cytotoxicity effect against MCF-7 and HCT-116 cell lines, for chloroform extract, IC(50) = 121.37 μg/mL (MCF-7) and 77.65 μg/mL (HCT-116), and for methanol extract, IC(50) = 46.11 μg/mL (MCF-7) and 59.29 μg/mL (HCT-116). However, the extracts prepared by sequential extraction procedure from dried starfish found to be ineffective. This study paves the way for further investigation on the peptide composition in the PBS extract of the starfish to discover potential chemotherapeutic agents.

  1. Basis set effects on the intermolecular interaction energies of methane dimers obtained by the Moeller-Plesset perturbation theory calculation

    SciTech Connect

    Tsuzuki, Seiji; Tanabe, Kazutoshi )

    1991-03-21

    Intermolecular interaction energies of methane dimer were calculated by using several basis sets up to 6-311G(3d,4p) with electron correlation energy correction by the Moeller-Plesset perturbation method and basis set superposition error (BSSE) correction by the counterpoise method to evaluate the basis set effect. The calculated interaction energies depended on the basis set considerably. Whereas the interaction energies of repulsive component calculated at HF level were not affected by the change of basis set, the dispersion energy component dependent greatly on the basis set used. The dispersion energies calculated with the Moeller-Plesset second- and third-order perturbation by using 6-311G(2d,2p) basis set were 0-10% and 4-6% smaller than those obtained with the fourth-order (MP4(SDTQ)) perturbation, respectively. The BSSE's calculated by the counterpoise method were still about 30% of the calculated intermolecular interaction energies for the conformers of energy minima event at the MP4(SDTQ)/6-311G(2d,2p) level. The calculated interaction potentials of dimers at the MP4(SDTQ)/6-311G(2d,2p) level were considerably shallower than those obtained by MM2 force fields but were close to the potentials given by the Williams potential and by the recently reported MM3 force field.

  2. Anti-leishmanial activity of alkaloidal extracts obtained from different organs of Aspidosperma ramiflorum.

    PubMed

    Cunha, Ananda de Castro; Chierrito, Talita Perez Cantuaria; Machado, Gerzia Maria de Carvalho; Leon, Leonor Laura Pinto; da Silva, Cleuza Conceição; Tanaka, Julio Cesar; de Souza, Lauro Mera; Gonçalves, Regina Aparecida Correia; de Oliveira, Arildo José Braz

    2012-03-15

    The present study was designated to evaluate semi-quantitative antileishmanial activity of alkaloidal extracts that were obtained from 1g of different parts of Aspidosperma ramiflorum (leaves, roots, seeds, and stem barks). Alkaloidal extracts of barks and leaves presented a good activity against the extracellular form (promastigotes) of Leishmania (L.) amazonensis. It is known that compounds responsible for the antileishmanial activity in the alkaloidal extracts from A. ramiflorum are the monoterpenoid indole alkaloids ramiflorine A and ramiflorine B, therefore extracts obtained from different plant parts were analyzed by electrospray ionization mass spectrometry (ESI-MS) in order to evidence the presence of these bioactive alkaloids. Based on these findings, alkaloidal extract from leaves was fractionated on preparative thin-layer chromatography in a bioassay-guided fractionation affording individual purified ramiflorines A and B. Both ramiflorines A and B showed significant activity against Leishmania (L.) amazonensis (LD(50) values of 18.5±6.5μg/ml and 12.63±5.52μg/ml, respectively). Our results are showing that alkaloidal extract from leaves is a promising alternative to the use of stem barks from A. ramiflorum.

  3. Obtaining the lattice energy of the anthracene crystal by modern yet affordable first-principles methods.

    PubMed

    Sancho-García, J C; Aragó, J; Ortí, E; Olivier, Y

    2013-05-28

    The non-covalent interactions in organic molecules are known to drive their self-assembly to form molecular crystals. We compare, in the case of anthracene and against experimental (electronic-only) sublimation energy, how modern quantum-chemical methods are able to calculate this cohesive energy taking into account all the interactions between occurring dimers in both first-and second-shells. These include both O(N(6))- and O(N(5))-scaling methods, Local Pair Natural Orbital-parameterized Coupled-Cluster Single and Double, and Spin-Component-Scaled-Møller-Plesset perturbation theory at second-order, respectively, as well as the most modern family of conceived density functionals: double-hybrid expressions in several variants (B2-PLYP, mPW2-PLYP, PWPB95) with customized dispersion corrections (-D3 and -NL). All-in-all, it is shown that these methods behave very accurately producing errors in the 1-2 kJ/mol range with respect to the experimental value taken into account the experimental uncertainty. These methods are thus confirmed as excellent tools for studying all kinds of interactions in chemical systems.

  4. Removing the barrier to the calculation of activation energies

    SciTech Connect

    Mesele, Oluwaseun O.; Thompson, Ward H.

    2016-10-06

    Approaches for directly calculating the activation energy for a chemical reaction from a simulation at a single temperature are explored with applications to both classical and quantum systems. The activation energy is obtained from a time correlation function that can be evaluated from the same molecular dynamics trajectories or quantum dynamics used to evaluate the rate constant itself and thus requires essentially no extra computational work.

  5. The bending potential energy function of HDO obtained from high-resolution data

    NASA Astrophysics Data System (ADS)

    Coudert, L. H.

    2016-12-01

    Line position and line intensity analyses of the high-resolution spectrum of the HDO isotopic species of the water molecule are performed with an extended version of the Bending-Rotation approach up to the (0 1 0) state and J = 22 . The line position analysis involves 3992 microwave, far infrared and infrared lines, and 421 experimental energy levels which were reproduced with a 1.1 unitless standard deviation. The data set considered in the line intensity analysis consists of 1405 infrared absorpon lines and 4 Stark coefficients fitted with a 1.2 unitless standard deviation. The results of both analyses are compared with previous investigations and are used to build a spectroscopic database which is compared with other available databases and should be useful for interpreting measurements carried out with the Infrared Atmospheric Sounding Interferometer (IASI).

  6. Evaluating Solar Resource Data Obtained from Multiple Radiometers Deployed at the National Renewable Energy Laboratory: Preprint

    SciTech Connect

    Habte, A.; Sengupta, M.; Andreas, A.; Wilcox, S.; Stoffel, T.

    2014-09-01

    Solar radiation resource measurements from radiometers are used to predict and evaluate the performance of photovoltaic and concentrating solar power systems, validate satellite-based models for estimating solar resources, and advance research in solar forecasting and climate change. This study analyzes the performance of various commercially available radiometers used for measuring global horizontal irradiances (GHI) and direct normal irradiances (DNI). These include pyranometers, pyrheliometers, rotating shadowband irradiometers, and a pyranometer with a shading ring deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory (SRRL). The radiometers in this study were deployed for one year (from April 1, 2011, through March 31, 2012) and compared to measurements from radiometers with the lowest values of estimated measurement uncertainties for producing reference GHI and DNI.

  7. Solar Energy Project, Activities: General Solar Topics.

    ERIC Educational Resources Information Center

    Tullock, Bruce, Ed.; And Others

    This guide contains lesson plans and outlines of activities which introduce students to concepts and issues relating to solar energy. Lessons frequently presented in the context of solar energy as it relates to contemporary energy problems. Each unit presents an introduction; objectives; necessary skills and knowledge; materials; method;…

  8. Activation energy for a model ferrous-ferric half reaction from transition path sampling.

    PubMed

    Drechsel-Grau, Christof; Sprik, Michiel

    2012-01-21

    Activation parameters for the model oxidation half reaction of the classical aqueous ferrous ion are compared for different molecular simulation techniques. In particular, activation free energies are obtained from umbrella integration and Marcus theory based thermodynamic integration, which rely on the diabatic gap as the reaction coordinate. The latter method also assumes linear response, and both methods obtain the activation entropy and the activation energy from the temperature dependence of the activation free energy. In contrast, transition path sampling does not require knowledge of the reaction coordinate and directly yields the activation energy [C. Dellago and P. G. Bolhuis, Mol. Simul. 30, 795 (2004)]. Benchmark activation energies from transition path sampling agree within statistical uncertainty with activation energies obtained from standard techniques requiring knowledge of the reaction coordinate. In addition, it is found that the activation energy for this model system is significantly smaller than the activation free energy for the Marcus model, approximately half the value, implying an equally large entropy contribution.

  9. Hybrid energy harvesting using active thermal backplane

    NASA Astrophysics Data System (ADS)

    Kim, Hyun-Wook; Lee, Dong-Gun

    2016-04-01

    In this study, we demonstrate the concept of a new hybrid energy harvesting system by combing solar cells with magneto-thermoelectric generator (MTG, i.e., thermal energy harvesting). The silicon solar cell can easily reach high temperature under normal operating conditions. Thus the heated solar cell becomes rapidly less efficient as the temperature of solar cell rises. To increase the efficiency of the solar cell, air or water-based cooling system is used. To surpass conventional cooling devices requiring additional power as well as large working space for air/water collectors, we develop a new technology of pairing an active thermal backplane (ATB) to solar cell. The ATB design is based on MTG technology utilizing the physics of the 2nd order phase transition of active ferromagnetic materials. The MTG is cost-effective conversion of thermal energy to electrical energy and is fundamentally different from Seebeck TEG devices. The ATB (MTG) is in addition to being an energy conversion system, a very good conveyor of heat through both conduction and convection. Therefore, the ATB can provide dual-mode for the proposed hybrid energy harvesting. One is active convective and conductive cooling for heated solar cell. Another is active thermal energy harvesting from heat of solar cell. These novel hybrid energy harvesting device have potentially simultaneous energy conversion capability of solar and thermal energy into electricity. The results presented can be used for better understanding of hybrid energy harvesting system that can be integrated into commercial applications.

  10. Effect of initial phase on error in electron energy obtained using paraxial approximation for a focused laser pulse in vacuum

    SciTech Connect

    Singh, Kunwar Pal; Arya, Rashmi; Malik, Anil K.

    2015-09-14

    We have investigated the effect of initial phase on error in electron energy obtained using paraxial approximation to study electron acceleration by a focused laser pulse in vacuum using a three dimensional test-particle simulation code. The error is obtained by comparing the energy of the electron for paraxial approximation and seventh-order correction description of the fields of Gaussian laser. The paraxial approximation predicts wrong laser divergence and wrong electron escape time from the pulse which leads to prediction of higher energy. The error shows strong phase dependence for the electrons lying along the axis of the laser for linearly polarized laser pulse. The relative error may be significant for some specific values of initial phase even at moderate values of laser spot sizes. The error does not show initial phase dependence for a circularly laser pulse.

  11. Sulfated modification of the polysaccharides obtained from defatted rice bran and their antitumor activities.

    PubMed

    Wang, Li; Li, Xiaoxuan; Chen, Zhengxing

    2009-03-01

    Nine sulfated defatted rice bran polysaccharides (sRBPS), with various degrees of sulfation (DS) and carbohydrate content, were prepared by chlorosulfonic acid-pyridine (CSA-Pyr) method according to orthogonal test. Nine sulfated derivatives sRBPS were obtained and their antitumor activities were compared by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results showed that when DS within the scope of 0.81-1.29, carbohydrate content in the range of 41.41-78.56%, sulfated derivatives exhibit relatively strong antitumor activity in vitro. The optimum modification conditions were reaction temperature of 70 degrees C, the ratio of chlorosulfonic acid to pyridine of 1:4 and the reaction time of 2h.

  12. Antifungal activity of itraconazole and voriconazole against clinical isolates obtained from animals with mycoses.

    PubMed

    Okabayashi, Ken; Imaji, Mashio; Osumi, Takafumi; Murakami, Yoshihiko; Maruyama, Haruhiko; Kano, Rui; Hasegawa, Atsuhiko; Watanabe, Toshi

    2009-01-01

    Animal mycosis, particularly deep mycosis, is one of the most challenging conditions encountered by veterinarians. Pathogens causing mycotic infections in animals include fungi such as Cryptococcus neoformans, Candida spp., and Aspergillus spp. The antifungal drugs used for the treatment of deep mycoses in animals as well as humans are polyenes and azoles. However, the sensitivity of clinical isolates obtained from animals toward these drugs has rarely been assayed. In this study, the antifungal activities of itraconazole and voriconazole against clinical isolates of C. neoformans, Candida spp., and A. fumigatus isolated from animals with mycoses were examined using the broth microdilution method performed according to the guidelines provided by the Clinical and Laboratory Standards Institute. The minimum inhibitory concentrations (MICs) of itraconazole toward the C. neoformans, Candida spp., and A. fumigatus isolates were 0.125 - 1, 0.125 - 2, and 0.25 - 2 microg/ml, respectively, and those of voriconazole were 0.0625 - 0.5, < or =0.0313 - 0.0625, and 0.0625 - 1 microg/ml, respectively. The results of the MIC analyses implied that the fungal isolates obtained from infected animals exhibit an equivalent degree of susceptibility to itraconazole and voriconazole, as is observed in the case of isolates obtained from humans. The appropriate antifungal therapeutic strategy for the treatment of mycoses in animals must be selected taking into consideration the host immune status and organ function as well as the in vitro sensitivity of the pathogens to antifungal drugs.

  13. Expansion of activated lymphocytes obtained from renal cell carcinoma in an automated hollow fiber bioreactor.

    PubMed

    Hillman, G G; Wolf, M L; Montecillo, E; Younes, E; Ali, E; Pontes, J E; Haas, G P

    1994-01-01

    Immunotherapy using IL-2 alone or combined with activated lymphocytes has been promising for metastatic renal cell carcinoma. Cytotoxic lymphocytes can be isolated from tumors, expanded in vitro with IL-2, and adoptively transferred back into the tumor-bearing host. These cells can also be transduced with the genes coding for cytokines for local delivery to tumor sites. A major drawback in adoptive immunotherapy is the cumbersome and expensive culture technology associated with the growth of large numbers of cells required for their therapeutic effect. To reduce the cost, resources, and manpower, we have developed the methodology for lymphocyte activation and expansion in the automated hollow fiber bioreactor IMMUNO*STAR Cell Expander (ACT BIOMEDICAL, INC). Tumor Infiltrating Lymphocytes (TIL) isolated from human renal cell carcinoma tumor specimens were inoculated at a number of 10(8) cells in a small bioreactor of 30 ml extracapillary space volume. We have determined the medium flow rates and culture conditions to obtain a significant and repeated expansion of TIL at weekly intervals. The lymphocytes cultured in the bioreactor demonstrated the same phenotype and cytotoxic activity as those expanded in parallel in tissue culture plates. Lymphocyte expansion in the hollow fiber bioreactor required lower volumes of medium, human serum, IL-2 and minimal labor. This technology may facilitate the use of adoptive immunotherapy for the treatment of refractory malignancies.

  14. Energy Conservation Activities, Grades 1-6.

    ERIC Educational Resources Information Center

    Northern Colorado Educational Board of Cooperative Services, Boulder.

    This publication is a collection of energy education activities for grades 1-6. The activities were written or selected to be used with daily lesson plans and the existing school curriculum. Activities are classified by: (1) content area (fine arts, mathematics, physical education, reading and language arts, science, and social studies; and (2)…

  15. Antioxidant activity, cytotoxic activity and metabolic profiling of juices obtained from saffron (Crocus sativus L.) floral by-products.

    PubMed

    Tuberoso, Carlo I G; Rosa, Antonella; Montoro, Paola; Fenu, Maurizio Antonio; Pizza, Cosimo

    2016-05-15

    Juices obtained from cold-pressed saffron (Crocus sativus L.) floral by-products were evaluated as a potential source of compounds with antioxidant and cytotoxic activities. Floral by-products were split in two batches for extraction 24 and 48h after flower harvesting, respectively. The in vitro anti-oxidant activity of these extracts was tested using the FRAP and DPPH assays, and two biological models of lipid oxidation (activity in preventing cholesterol degradation and protection against Cu(2+)-mediated degradation of the liposomal unsaturated fatty acids). The cytotoxic activity was evaluated using the MTT assay. The results show that extracts obtained 48h post-harvest contained higher levels of total polar phenols and had the highest antioxidant activity in all of the performed assays. The LC-DAD and LC-ESI-(HR)MS(n) metabolic profiles showed high levels of kaempferol derivatives and anthocyanins. This study suggests that juices from saffron floral by-products could potentially be used to develop new products for the food and health industry.

  16. Method for obtaining electron energy-density functions from Langmuir-probe data using a card-programmable calculator

    SciTech Connect

    Longhurst, G.R.

    1981-01-01

    This paper presents a method for obtaining electron energy density functions from Langmuir probe data taken in cool, dense plasmas where thin-sheath criteria apply and where magnetic effects are not severe. Noise is filtered out by using regression of orthogonal polynomials. The method requires only a programmable calculator (TI-59 or equivalent) to implement and can be used for the most general, nonequilibrium electron energy distribution plasmas. Data from a mercury ion source analyzed using this method are presented and compared with results for the same data using standard numerical techniques.

  17. A method for obtaining electron energy density functions from Langmuir probe data using a card-programable calculator

    NASA Astrophysics Data System (ADS)

    Longhurst, G. R.

    1981-04-01

    This paper presents a method for obtaining electron energy density functions from Langmuir probe data taken in cool, dense plasmas where thin-sheath criteria apply and where magnetic effects are not severe. Noise is filtered out by using regression of orthogonal polynomials. The method requires only a programable calculator (TI-59 or equivalent) to implement and can be used for the most general, nonequilibrium electron energy distribution plasmas. Data from a mercury ion source analyzed using this method are presented and compared with results for the same data using standard numerical techniques.

  18. Development of an apparatus for obtaining molecular beams in the energy range from 2 to 200 eV

    NASA Technical Reports Server (NTRS)

    Clapier, R.; Devienne, F. M.; Roustan, A.; Roustan, J. C.

    1985-01-01

    The formation and detection of molecular beams obtained by charge exchange from a low-energy ion source is discussed. Dispersion in energy of the ion source was measured and problems concerning detection of neutral beams were studied. Various methods were used, specifically secondary electron emissivity of a metallic surface and ionization of a gas target with a low ionization voltage. The intensities of neutral beams as low as 10 eV are measured by a tubular electron multiplier and a lock-in amplifier.

  19. Fetal Functional Brain Age Assessed from Universal Developmental Indices Obtained from Neuro-Vegetative Activity Patterns

    PubMed Central

    Hoyer, Dirk; Tetschke, Florian; Jaekel, Susan; Nowack, Samuel; Witte, Otto W.; Schleußner, Ekkehard; Schneider, Uwe

    2013-01-01

    Fetal brain development involves the development of the neuro-vegetative (autonomic) control that is mediated by the autonomic nervous system (ANS). Disturbances of the fetal brain development have implications for diseases in later postnatal life. In that context, the fetal functional brain age can be altered. Universal principles of developmental biology applied to patterns of autonomic control may allow a functional age assessment. The work aims at the development of a fetal autonomic brain age score (fABAS) based on heart rate patterns. We analysed n = 113 recordings in quiet sleep, n = 286 in active sleep, and n = 29 in active awakeness from normals. We estimated fABAS from magnetocardiographic recordings (21.4–40.3 weeks of gestation) preclassified in quiet sleep (n = 113, 63 females) and active sleep (n = 286, 145 females) state by cross-validated multivariate linear regression models in a cross-sectional study. According to universal system developmental principles, we included indices that address increasing fluctuation range, increasing complexity, and pattern formation (skewness, power spectral ratio VLF/LF, pNN5). The resulting models constituted fABAS. fABAS explained 66/63% (coefficient of determination R2 of training and validation set) of the variance by age in quiet, while 51/50% in active sleep. By means of a logistic regression model using fluctuation range and fetal age, quiet and active sleep were automatically reclassified (94.3/93.1% correct classifications). We did not find relevant gender differences. We conclude that functional brain age can be assessed based on universal developmental indices obtained from autonomic control patterns. fABAS reflect normal complex functional brain maturation. The presented normative data are supplemented by an explorative study of 19 fetuses compromised by intrauterine growth restriction. We observed a shift in the state distribution towards active awakeness. The lower WGA dependent f

  20. Convulsant activity and neurochemical alterations induced by a fraction obtained from fruit Averrhoa carambola (Oxalidaceae: Geraniales).

    PubMed

    Carolino, Ruither O G; Beleboni, Renê O; Pizzo, Andrea B; Vecchio, Flavio Del; Garcia-Cairasco, Norberto; Moyses-Neto, Miguel; Santos, Wagner F Dos; Coutinho-Netto, Joaquim

    2005-06-01

    We obtained a neurotoxic fraction (AcTx) from star fruit (Averrhoa carambola) and studied its effects on GABAergic and glutamatergic transmission systems. AcTx had no effect on GABA/glutamate uptake or release, or on glutamate binding. However, it specifically inhibited GABA binding in a concentration-dependent manner (IC(50)=0.89muM). Video-electroencephalogram recordings demonstrated that following cortical administration of AcTx, animals showed behavioral changes, including tonic-clonic seizures, evolving into status epilepticus, accompanied by cortical epileptiform activity. Chemical characterization of AcTx showed that this compound is a nonproteic molecule with a molecular weight less than 500, differing from oxalic acid. This neurotoxic fraction of star fruit may be considered a new tool for neurochemical and neuroethological research.

  1. Photocatalytic Activity of Nanostructured Anatase Coatings Obtained by Cold Gas Spray

    NASA Astrophysics Data System (ADS)

    Gardon, M.; Fernández-Rodríguez, C.; Garzón Sousa, D.; Doña-Rodríguez, J. M.; Dosta, S.; Cano, I. G.; Guilemany, J. M.

    2014-10-01

    This article describes a photocatalytic nanostructured anatase coating deposited by cold gas spray (CGS) supported on titanium sub-oxide (TiO2- x ) coatings obtained by atmospheric plasma spray (APS) onto stainless steel cylinders. The photocatalytic coating was homogeneous and preserved the composition and nanostructure of the starting powder. The inner titanium sub-oxide coating favored the deposition of anatase particles in the solid state. Agglomerated nano-TiO2 particles fragmented when impacting onto the hard surface of the APS TiO2- x bond coat. The rough surface provided by APS provided an ideal scenario for entrapping the nanostructured particles, which may be adhered onto the bond coat due to chemical bonding; a possible bonding mechanism is described. Photocatalytic experiments showed that CGS nano-TiO2 coating was active for photodegrading phenol and formic acid under aqueous conditions. The results were similar to the performance obtained by competitor technologies and materials such as dip-coating P25® photocatalysts. Disparity in the final performance of the photoactive materials may have been caused by differences in grain size and the crystalline composition of titanium dioxide.

  2. Antileishmanial activity of the essential oil from Tetradenia riparia obtained in different seasons

    PubMed Central

    Cardoso, Bruna Muller; de Mello, Tatiane França Perles; Lopes, Sara Negrão; Demarchi, Izabel Galhardo; Lera, Daniele Stefani Lopes; Pedroso, Raíssa Bocchi; Cortez, Diogenes Aparício; Gazim, Zilda Cristiani; Aristides, Sandra Mara Alessi; Silveira, Thais Gomes Verzignassi; Lonardoni, Maria Valdrinez Campana

    2015-01-01

    The herbaceous shrub Tetradenia riparia has been traditionally used to treat inflammatory and infectious diseases. Recently, a study showed that T. riparia essential oil (TrEO) obtained in summer has antileishmanial effects, although these results could be influenced by seasonal variation. This study evaluated the activity of the TrEO obtained in different seasons against Leishmania (Leishmania) amazonensis, in vitro and in vivo. The compounds in the TrEO were analysed by gas chromatography-mass spectrometry; terpenoids were present and oxygenated sesquiterpenes were the majority compounds (55.28%). The cytotoxicity and nitric oxide (NO) production were also tested after TrEO treatment. The TrEO from all seasons showed a 50% growth inhibitory concentration for promastigotes of about 15 ng/mL; at 30 ng/mL and 3 ng/mL, the TrEO reduced intracellular amastigote infection, independently of season. The TrEO from plants harvested in summer had the highest 50% cytotoxic concentration, 1,476 ng/mL for J774.A1 macrophages, and in spring (90.94 ng/mL) for murine macrophages. NO production did not change in samples of the TrEO from different seasons. The antileishmanial effect in vivo consisted of a reduction of the parasite load in the spleen. These results suggest that the TrEO has potential effects on L. (L.) amazonensis, consonant with its traditional use to treat parasitic diseases. PMID:26602873

  3. Antileishmanial activity of the essential oil from Tetradenia riparia obtained in different seasons.

    PubMed

    Cardoso, Bruna Muller; de Mello, Tatiane França Perles; Lopes, Sara Negrão; Demarchi, Izabel Galhardo; Lera, Daniele Stefani Lopes; Pedroso, Raíssa Bocchi; Cortez, Diogenes Aparício; Gazim, Zilda Cristiani; Aristides, Sandra Mara Alessi; Silveira, Thais Gomes Verzignassi; Lonardoni, Maria Valdrinez Campana

    2015-12-01

    The herbaceous shrub Tetradenia riparia has been traditionally used to treat inflammatory and infectious diseases. Recently, a study showed that T. riparia essential oil (TrEO) obtained in summer has antileishmanial effects, although these results could be influenced by seasonal variation. This study evaluated the activity of the TrEO obtained in different seasons against Leishmania (Leishmania) amazonensis, in vitro and in vivo. The compounds in the TrEO were analysed by gas chromatography-mass spectrometry; terpenoids were present and oxygenated sesquiterpenes were the majority compounds (55.28%). The cytotoxicity and nitric oxide (NO) production were also tested after TrEO treatment. The TrEO from all seasons showed a 50% growth inhibitory concentration for promastigotes of about 15 ng/mL; at 30 ng/mL and 3 ng/mL, the TrEO reduced intracellular amastigote infection, independently of season. The TrEO from plants harvested in summer had the highest 50% cytotoxic concentration, 1,476 ng/mL for J774.A1 macrophages, and in spring (90.94 ng/mL) for murine macrophages. NO production did not change in samples of the TrEO from different seasons. The antileishmanial effect in vivo consisted of a reduction of the parasite load in the spleen. These results suggest that the TrEO has potential effects on L. (L.) amazonensis, consonant with its traditional use to treat parasitic diseases.

  4. Improved free-energy interpolation scheme for obtaining gas-phase reaction rates from ring-polymer molecular dynamics

    NASA Astrophysics Data System (ADS)

    Stecher, Thomas; Althorpe, Stuart C.

    2012-05-01

    Quantum reaction rates for bimolecular gas-phase reactions can be computed efficiently and to a realistic degree of approximation by applying ring-polymer molecular dynamics within a free-energy interpolation scheme [R. Collepardo-Guevara, Y.V. Suleimanov, and D.E. Manolopoulos, J. Chem. Phys. 130, 174713 (2009)]. Here, we present modifications to this scheme which simplify the implementation of the method, and have the advantage of yielding directly the free-energy as a function of the interpolation coordinate. We also take the opportunity to verify the benchmark results obtained for the H + H2 and Cl + HCl reactions by Collepardo-Guevara et al., obtaining excellent agreement for H + H2 and reasonable agreement for Cl + HCl.

  5. Energy intake, physical activity, energy balance, and cancer: epidemiologic evidence.

    PubMed

    Pan, Sai Yi; DesMeules, Marie

    2009-01-01

    Energy intake, physical activity, and obesity are modifiable lifestyle factors. This chapter reviews and summarizes the epidemiologic evidence on the relation of energy intake, physical activity, and obesity to cancer. High energy intake may increase the risk of cancers of colon-rectum, prostate (especially advanced prostate cancer), and breast. However, because physical activity, body size, and metabolic efficiency are highly related to total energy intake and expenditure, it is difficult to assess the independent effect of energy intake on cancer risk. There are sufficient evidences to support a role of physical activity in preventing cancers of the colon and breast, whereas the association is stronger in men than in women for colon cancer and in postmenopausal than in premenopausal women for breast cancer. The evidence also suggests that physical activity likely reduces the risk of cancers of endometrium, lung, and prostate (to a lesser extent). On the other hand, there is little or no evidence that the risk of rectal cancer is related to physical activity, whereas the results have been inconsistent regarding the association between physical activity and the risks of cancers of pancreas, ovary and kidney. Epidemiologic studies provide sufficient evidence that obesity is a risk factor for both cancer incidence and mortality. The evidence supports strong links of obesity with the risk of cancers of the colon, rectum, breast (in postmenopausal women), endometrium, kidney (renal cell), and adenocarcinoma of the esophagus. Epidemiologic evidence also indicates that obesity is probably related to cancers of the pancreas, liver, and gallbladder, and aggressive prostate cancer, while it seems that obesity is not associated with lung cancer. The role of obesity in other cancer risks is unclear.

  6. Sulfation modification and anticoagulant activity of the polysaccharides obtained from persimmon (Diospyros kaki L.) fruits.

    PubMed

    Lu, Xiaoyun; Mo, Xiaoyan; Guo, Hui; Zhang, Yali

    2012-12-01

    The optimal conditions for sulfation of polysaccharides from persimmon fruits (PFP) with chlorosulfonic acid-pyridine (CSA-Pyr) method were determined by response surface methodology. Box-Behnken design was applied to evaluate the effects of three independent variables (volume ratio of Pyr to CSA, volume ratio of PFP to SO(3)Pyr and reaction time) on the degree of substitution (DS), molecular weight (MW) and activated partial thromboplastin time (APTT) of sulfated polysaccharides (PFP-S). The APTT activity of PFP-S could be improved by application of various volume ratio of Pyr to CSA, volume ratio of PFP to SO(3)Pyr and reaction time, which was possible due to the degradation of polysaccharides to different extent and increasing of DS. The optimal conditions to obtain the strongest APTT of PFP-S were the volume ratio of CSA to Pyr of 1:8, the volume ratio of SO(3)Pyr to PFP of 1:3.6 and the reaction time of 3 h, respectively.

  7. Obtaining the solid-liquid interfacial free energy via multi-scheme thermodynamic integration: Ag-ethylene glycol interfaces

    NASA Astrophysics Data System (ADS)

    Qi, Xin; Zhou, Ya; Fichthorn, Kristen A.

    2016-11-01

    The solid-liquid interfacial free energy γs l is an important quantity in wetting, nucleation, and crystal growth. Although various methods have been developed to calculate γs l with atomic-scale simulations, such calculations still remain challenging for multi-component interfaces between molecular fluids and solids. We present a multi-scheme thermodynamic integration method that is inspired by the "cleaving-wall" method and aimed at obtaining γs l for such systems using open-source simulation packages. This method advances two aspects of its predecessor methods. First, we incorporate separate schemes to resolve difficulties when manipulating periodic boundary conditions of the supercell using open-source simulation packages. Second, we introduce a numerical approximation to obtain thermodynamic integrands for complex force fields when an analytical differentiation is not readily available. To demonstrate this method, we obtain γs l for interfaces between Ag(100) and Ag(111) and ethylene glycol (EG). These interfacial free energies mirror interfacial potential energies for each facet. We also estimate entropies of interface formation and these are consistent with theoretical predictions in signs and trends. For the Ag-EG systems, we find that the largest contribution to γs l is the free energy to create the bare metal surfaces. The second-largest contribution to γs l is from the liquid-solid interaction. This user-friendly method will accelerate investigation in a broad range of research topics, such as the thermodynamic effect of structure-directing agents in solution-phase shape-controlled nanocrystal syntheses.

  8. Nickel(II) adsorption onto biomass based activated carbon obtained from sugarcane bagasse pith.

    PubMed

    Krishnan, K Anoop; Sreejalekshmi, K G; Baiju, R S

    2011-11-01

    Bioavailability of Nickel in the form of hydrated Nickel(II) attributes to its toxicological effects and hence its removal from aqueous solution is of great concern. Adsorption is used as an efficient technique for the removal of Nickel(II), hereafter Ni(II), from water and wastewaters. Activated carbon obtained from sugarcane bagasse pith (SBP-AC), a waste biomass collected from juice shops in Sarkara Devi Temple, Chirayinkeezhu, Trivandrum, India during annual festival, is used as adsorbent in the study. The process of adsorption is highly dependent on solution pH, and maximum removal occurs in the pH range of 4.0-8.0. Moreover, the amount of Ni(II) adsorbed onto SBP-AC increased with the time increase and reached equilibrium at 4h. Adsorption kinetic and equilibrium data were analyzed for determining the best fit kinetic and isotherm models. The overall study reveals the potential value of steam pyrolysed SBP-AC as a possible commercial adsorbent in wastewater treatment strategies.

  9. Chemical activation through super energy transfer collisions.

    PubMed

    Smith, Jonathan M; Nikow, Matthew; Ma, Jianqiang; Wilhelm, Michael J; Han, Yong-Chang; Sharma, Amit R; Bowman, Joel M; Dai, Hai-Lung

    2014-02-05

    Can a molecule be efficiently activated with a large amount of energy in a single collision with a fast atom? If so, this type of collision will greatly affect molecular reactivity and equilibrium in systems where abundant hot atoms exist. Conventional expectation of molecular energy transfer (ET) is that the probability decreases exponentially with the amount of energy transferred, hence the probability of what we label "super energy transfer" is negligible. We show, however, that in collisions between an atom and a molecule for which chemical reactions may occur, such as those between a translationally hot H atom and an ambient acetylene (HCCH) or sulfur dioxide, ET of chemically significant amounts of energy commences with surprisingly high efficiency through chemical complex formation. Time-resolved infrared emission observations are supported by quasi-classical trajectory calculations on a global ab initio potential energy surface. Results show that ∼10% of collisions between H atoms moving with ∼60 kcal/mol energy and HCCH result in transfer of up to 70% of this energy to activate internal degrees of freedom.

  10. Low Energy Physical Activity Recognition System on Smartphones

    PubMed Central

    Morillo, Luis Miguel Soria; Gonzalez-Abril, Luis; Ramirez, Juan Antonio Ortega; de la Concepcion, Miguel Angel Alvarez

    2015-01-01

    An innovative approach to physical activity recognition based on the use of discrete variables obtained from accelerometer sensors is presented. The system first performs a discretization process for each variable, which allows efficient recognition of activities performed by users using as little energy as possible. To this end, an innovative discretization and classification technique is presented based on the χ2 distribution. Furthermore, the entire recognition process is executed on the smartphone, which determines not only the activity performed, but also the frequency at which it is carried out. These techniques and the new classification system presented reduce energy consumption caused by the activity monitoring system. The energy saved increases smartphone usage time to more than 27 h without recharging while maintaining accuracy. PMID:25742171

  11. Quantification of active pharmaceutical ingredient and impurities in sildenafil citrate obtained from the Internet

    PubMed Central

    Nutan, Mohammad T.; Dodla, Uday Krishna Reddy

    2014-01-01

    Background: The accessibility of prescription drugs produced outside of the United States, most notably sildenafil citrate (innovator product, Viagra®), has been made much easier by the Internet. Of greatest concern to clinicians and policymakers is product quality and patient safety. The US Food and Drug Administration (FDA) has issued warnings to potential buyers that the safety of drugs purchased from the Internet cannot be guaranteed, and may present a health risk to consumers from substandard products. Objective: The objective of this study was to determine whether generic sildenafil citrate tablets from international markets obtained via the Internet are equivalent to the US innovator product regarding major aspects of pharmaceutical quality: potency, accuracy of labeling, and presence and level of impurities. This will help identify aspects of drug quality that may impact public health risks. Methods: A total of 15 sildenafil citrate tablets were obtained for pharmaceutical analysis: 14 generic samples from international Internet pharmacy websites and the US innovator product. According to US Pharmacopeial guidelines, tablet samples were tested using high-performance liquid chromatography for potency of active pharmaceutical ingredient (API) and levels of impurities (impurities A, B, C, and D). Impurity levels were compared with International Conference on Harmonisation (ICH) limits. Results: Among the 15 samples, 4 samples possessed higher impurity B levels than the ICH qualification threshold, 8 samples possessed higher impurity C levels than the ICH qualification threshold, and 4 samples possessed more than 1% impurity quantity of maximum daily dose (MDD). For API, 6 of the samples failed to fall within the 5% assay limit. Conclusions: Quality assurance tests are often used to detect formulation defects of drug products during the manufacturing and/or storage process. Results suggest that manufacturing standards for sildenafil citrate generic drug

  12. Osteogenic activity of titanium surfaces with hierarchical micro-/nano-structures obtained by hydrofluoric acid treatment.

    PubMed

    Liang, Jianfei; Xu, Shanshan; Shen, Mingming; Cheng, Bingkun; Li, Yongfeng; Liu, Xiangwei; Qin, Dongze; Bellare, Anuj; Kong, Liang

    2017-01-01

    An easier method for constructing the hierarchical micro-/nano-structures on the surface of dental implants in the clinic is needed. In this study, three different titanium surfaces with microscale grooves (width 0.5-1, 1-1.5, and 1.5-2 μm) and nanoscale nanoparticles (diameter 20-30, 30-50, and 50-100 nm, respectively) were obtained by treatment with different concentrations of hydrofluoric acid (HF) and at different etching times (1%, 3 min; 0.5%, 12 min; and 1.5%, 12 min, respectively; denoted as groups HF1, HF2, and HF3). The biological response to the three different titanium surfaces was evaluated by in vitro human bone marrow-derived mesenchymal stem cell (hBMMSC) experiments and in vivo animal experiments. The results showed that cell adhesion, proliferation, alkaline phosphatase activity, and mineralization of hBMMSCs were increased in the HF3 group. After the different surface implants were inserted into the distal femurs of 40 rats, the bone-implant contact in groups HF1, HF2, and HF3 was 33.17%±2.2%, 33.82%±3.42%, and 41.04%±3.08%, respectively. Moreover, the maximal pullout force in groups HF1, HF2, and HF3 was 57.92±2.88, 57.83±4.09, and 67.44±6.14 N, respectively. The results showed that group HF3 with large micron grooves (1.5-2.0 μm) and large nanoparticles (50-100 nm) showed the best bio-functionality for the hBMMSC response and osseointegration in animal experiments compared with other groups.

  13. Osteogenic activity of titanium surfaces with hierarchical micro-/nano-structures obtained by hydrofluoric acid treatment

    PubMed Central

    Liang, Jianfei; Xu, Shanshan; Shen, Mingming; Cheng, Bingkun; Li, Yongfeng; Liu, Xiangwei; Qin, Dongze; Bellare, Anuj; Kong, Liang

    2017-01-01

    An easier method for constructing the hierarchical micro-/nano-structures on the surface of dental implants in the clinic is needed. In this study, three different titanium surfaces with microscale grooves (width 0.5–1, 1–1.5, and 1.5–2 μm) and nanoscale nanoparticles (diameter 20–30, 30–50, and 50–100 nm, respectively) were obtained by treatment with different concentrations of hydrofluoric acid (HF) and at different etching times (1%, 3 min; 0.5%, 12 min; and 1.5%, 12 min, respectively; denoted as groups HF1, HF2, and HF3). The biological response to the three different titanium surfaces was evaluated by in vitro human bone marrow-derived mesenchymal stem cell (hBMMSC) experiments and in vivo animal experiments. The results showed that cell adhesion, proliferation, alkaline phosphatase activity, and mineralization of hBMMSCs were increased in the HF3 group. After the different surface implants were inserted into the distal femurs of 40 rats, the bone–implant contact in groups HF1, HF2, and HF3 was 33.17%±2.2%, 33.82%±3.42%, and 41.04%±3.08%, respectively. Moreover, the maximal pullout force in groups HF1, HF2, and HF3 was 57.92±2.88, 57.83±4.09, and 67.44±6.14 N, respectively. The results showed that group HF3 with large micron grooves (1.5–2.0 μm) and large nanoparticles (50–100 nm) showed the best bio-functionality for the hBMMSC response and osseointegration in animal experiments compared with other groups. PMID:28243092

  14. Assessment of national systems for obtaining local acceptance of waste management siting and routing activities

    SciTech Connect

    Paige, H.W.; Lipman, D.S.; Owens, J.E.

    1980-07-01

    There is a rich mixture of formal and informal approaches being used in our sister nuclear democracies in their attempts to deal with the difficulties of obtaining local acceptance for siting of waste management facilities and activities. Some of these are meeting with a degree of success not yet achieved in the US. Although this survey documents and assesses many of these approaches, time did not permit addressing in any detail their relevance to common problems in the US. It would appear the US could benefit from a periodic review of the successes and failures of these efforts, including analysis of their applicability to the US system. Of those countries (Germany, Sweden, Switzerland, Japan, Belgium, and the US) who are working to a time table for the preparation of a high-level waste (HLW) repository, Germany is the only country to have gained local siting acceptance for theirs. With this (the most difficult of siting problems) behind them they appear to be in the best overall condition relative to waste management progress and plans. This has been achieved without a particularly favorable political structure, made up for by determination on the part of the political leadership. Of the remaining three countries studied (France, UK and Canada) France, with its AVM production facility, is clearly the world leader in the HLW immobilization aspect of waste management. France, Belgium and the UK appear to have the least favorable political structures and environments for arriving at waste management decisions. US, Switzerland and Canada appear to have the least favorable political structures and environments for arriving at waste management decisions.

  15. 10 CFR 708.19 - How can a party obtain review by the Secretary of Energy of a decision on appeal of a dismissal?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false How can a party obtain review by the Secretary of Energy of a decision on appeal of a dismissal? 708.19 Section 708.19 Energy DEPARTMENT OF ENERGY DOE CONTRACTOR EMPLOYEE PROTECTION PROGRAM Employee Complaint Resolution Process § 708.19 How can a party obtain review by the Secretary of Energy of a...

  16. High current density ion beam obtained by a transition to a highly focused state in extremely low-energy region

    SciTech Connect

    Hirano, Y. E-mail: hirano.yoichi@phys.cst.nihon-u.ac.jp; Kiyama, S.; Koguchi, H.; Fujiwara, Y.; Sakakita, H.

    2015-11-15

    A high current density (≈3 mA/cm{sup 2}) hydrogen ion beam source operating in an extremely low-energy region (E{sub ib} ≈ 150–200 eV) has been realized by using a transition to a highly focused state, where the beam is extracted from the ion source chamber through three concave electrodes with nominal focal lengths of ≈350 mm. The transition occurs when the beam energy exceeds a threshold value between 145 and 170 eV. Low-level hysteresis is observed in the transition when E{sub ib} is being reduced. The radial profiles of the ion beam current density and the low temperature ion current density can be obtained separately using a Faraday cup with a grid in front. The measured profiles confirm that more than a half of the extracted beam ions reaches the target plate with a good focusing profile with a full width at half maximum of ≈3 cm. Estimation of the particle balances in beam ions, the slow ions, and the electrons indicates the possibility that the secondary electron emission from the target plate and electron impact ionization of hydrogen may play roles as particle sources in this extremely low-energy beam after the compensation of beam ion space charge.

  17. High current density ion beam obtained by a transition to a highly focused state in extremely low-energy region.

    PubMed

    Hirano, Y; Kiyama, S; Fujiwara, Y; Koguchi, H; Sakakita, H

    2015-11-01

    A high current density (≈3 mA/cm(2)) hydrogen ion beam source operating in an extremely low-energy region (E(ib) ≈ 150-200 eV) has been realized by using a transition to a highly focused state, where the beam is extracted from the ion source chamber through three concave electrodes with nominal focal lengths of ≈350 mm. The transition occurs when the beam energy exceeds a threshold value between 145 and 170 eV. Low-level hysteresis is observed in the transition when E(ib) is being reduced. The radial profiles of the ion beam current density and the low temperature ion current density can be obtained separately using a Faraday cup with a grid in front. The measured profiles confirm that more than a half of the extracted beam ions reaches the target plate with a good focusing profile with a full width at half maximum of ≈3 cm. Estimation of the particle balances in beam ions, the slow ions, and the electrons indicates the possibility that the secondary electron emission from the target plate and electron impact ionization of hydrogen may play roles as particle sources in this extremely low-energy beam after the compensation of beam ion space charge.

  18. Conservation Activities Related to Energy: Energy Activities for Urban Elementary Students, K-6.

    ERIC Educational Resources Information Center

    Schmidt, Joan S.; And Others

    Presented are simple activities, experiments, and demonstrations relating to energy conservation in the home. Activities are divided into four areas: (1) kitchen, (2) house, (3) transportation, and (4) heating and cooling. The material has been designed to require a minimum of preparation. Activity and game masters are provided. Activities may be…

  19. Energy Activities for Junior High Social Studies.

    ERIC Educational Resources Information Center

    Minnesota State Energy Agency, St. Paul.

    The document contains seven learning activities for junior high students on the energy situation. Objectives are to help students gain understanding and knowledge about the relationships between humans and their social and physical environments; solve problems and clarify issues; examine personal beliefs and values; and recognize the relationships…

  20. Solar Energy Project, Activities: Chemistry & Physics.

    ERIC Educational Resources Information Center

    Tullock, Bruce, Ed.; And Others

    This guide contains lesson plans and outlines of science activities which present concepts of solar energy in the context of chemistry and physics experiments. Each unit presents an introduction to the unit; objectives; required skills and knowledge; materials; method; questions; recommendations for further work; and a teacher information sheet.…

  1. The Magnetic Free Energy in Active Regions

    NASA Technical Reports Server (NTRS)

    Metcalf, Thomas R.; Mickey, Donald L.; LaBonte, Barry J.

    2001-01-01

    The magnetic field permeating the solar atmosphere governs much of the structure, morphology, brightness, and dynamics observed on the Sun. The magnetic field, especially in active regions, is thought to provide the power for energetic events in the solar corona, such as solar flares and Coronal Mass Ejections (CME) and is believed to energize the hot coronal plasma seen in extreme ultraviolet or X-rays. The question remains what specific aspect of the magnetic flux governs the observed variability. To directly understand the role of the magnetic field in energizing the solar corona, it is necessary to measure the free magnetic energy available in active regions. The grant now expiring has demonstrated a new and valuable technique for observing the magnetic free energy in active regions as a function of time.

  2. Nitroreductase-triggered activation of a novel caged fluorescent probe obtained from methylene blue.

    PubMed

    Bae, Jungeun; McNamara, Louis E; Nael, Manal A; Mahdi, Fakhri; Doerksen, Robert J; Bidwell, Gene L; Hammer, Nathan I; Jo, Seongbong

    2015-08-18

    A near-infrared fluorescent probe based on methylene blue (p-NBMB) was developed for the detection of nitroreductase. Conjugating methylene blue with a p-nitrobenzyl moiety enables it to be activated by nitroreductase-catalyzed 1,6-elimination, resulting in the release of an active methylene blue fluorophore.

  3. Predicting the biological effects of mobile phone radiation absorbed energy linked to the MRI-obtained structure.

    PubMed

    Krstić, Dejan; Zigar, Darko; Petković, Dejan; Sokolović, Dušan; Dinđić, Boris; Cvetković, Nenad; Jovanović, Jovica; Dinđić, Nataša

    2013-01-01

    The nature of an electromagnetic field is not the same outside and inside a biological subject. Numerical bioelectromagnetic simulation methods for penetrating electromagnetic fields facilitate the calculation of field components in biological entities. Calculating energy absorbed from known sources, such as mobile phones when placed near the head, is a prerequisite for studying the biological influence of an electromagnetic field. Such research requires approximate anatomical models which are used to calculate the field components and absorbed energy. In order to explore the biological effects in organs and tissues, it is necessary to establish a relationship between an analogous anatomical model and the real structure. We propose a new approach in exploring biological effects through combining two different techniques: 1) numerical electromagnetic simulation, which is used to calculate the field components in a similar anatomical model and 2) Magnetic Resonance Imaging (MRI), which is used to accurately locate sites with increased absorption. By overlapping images obtained by both methods, we can precisely locate the spots with maximum absorption effects. This way, we can detect the site where the most pronounced biological effects are to be expected. This novel approach successfully overcomes the standard limitations of working with analogous anatomical models.

  4. Energy Expenditure During Extravehicular Activity Through Apollo

    NASA Technical Reports Server (NTRS)

    Paul, Heather L.

    2011-01-01

    Monitoring crew health during manned space missions has always been an important factor to ensure that the astronauts can complete the missions successfully and within safe physiological limits. The necessity of real-time metabolic rate monitoring during extravehicular activities (EVAs) came into question during the Gemini missions, when the energy expenditure required to complete EVA tasks exceeded the life support capabilities for cooling and humidity control and crewmembers (CMs) ended the EVAs fatigued and overworked. This paper discusses the importance of real-time monitoring of metabolic rate during EVA, and provides a historical look at energy expenditure during EVA through the Apollo program.

  5. Energy Expenditure During Extravehicular Activity Through Apollo

    NASA Technical Reports Server (NTRS)

    Paul, Heather L.

    2012-01-01

    Monitoring crew health during manned space missions has always been an important factor to ensure that the astronauts can complete the missions successfully and within safe physiological limits. The necessity of real-time metabolic rate monitoring during extravehicular activities (EVAs) came into question during the Gemini missions, when the energy expenditure required to complete EVA tasks exceeded the life support capabilities for cooling and humidity control and, as a result, crew members ended the EVAs fatigued and overworked. This paper discusses the importance of real-time monitoring of metabolic rate during EVAs, and provides a historical look at energy expenditure during EVAs through the Apollo Program.

  6. Antioxidant activities of polysaccharides obtained from Chlorella pyrenoidosa via different ethanol concentrations.

    PubMed

    Chen, Yi-Xuan; Liu, Xiao-Yan; Xiao, Zheng; Huang, Yi-Fan; Liu, Bin

    2016-10-01

    An ultrasonic-assisted extraction of Chlorella pyrenoidosa polysaccharides (CPP) was carried out using different concentrations of ethanol for precipitation, and named as CPP60, CPP70 and CPP85, respectively. The monosaccharide composition of each polysaccharide (CPP) was determined using gas chromatography (GC) and the antioxidant activity of each was investigated via the reducing power and scavenging activity of hydroxyl radicals, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and superoxide anion radicals, respectively. All of the polysaccharides examined possessed antioxidant activity in vitro. CPP70 exhibited stronger scavenging activity against superoxide, DPPH and hydroxyl radicals, when compared with CPP60 and CPP85. This suggests that polysaccharides from C. pyrenoidosa precipitated by a final ethanol concentration of 70%, have the potential to be developed as natural antioxidants for use in food and pharmaceuticals.

  7. Aggregation and Disaggregation Techniques Applied on Remotely Sensed Data to Obtain Optimum Resolution for Surface Energy Fluxes Estimation

    NASA Astrophysics Data System (ADS)

    Agam, N.; Kustas, W. P.; Li, F.; Anderson, M. C.

    2006-05-01

    Continuous monitoring of surface energy fluxes provides an important tool for precision agriculture management. It is, therefore, desirable to obtain these fluxes at agricultural field size (length scale ~ 10-100 m). To date, land surface temperature (LST), a fundamental input required for flux computations, is usually available at a nominal resolution of 1 km, which disables field-scale monitoring. Disaggregating LST data into field-scale sub-pixels was found to be possible, with deterioration in temperature accuracy as sub-pixel size is reduced. In contrast to LST, land use and fractional vegetation cover (LU and FC, additional key inputs) are available at high spatial resolution (e.g., 30 m). Aggregation of LU and FC to meet the lower resolution LST data introduces errors when aggregating to larger pixel sizes. The objective of this research is to find the optimum resolution that will minimize the errors due to aggregation of LU/FC and disaggregation of LST data, to provide continuous estimates of field scale surface energy fluxes. Data were used from the 2002 Soil Moisture-Atmosphere Coupling Experiment (SMACEX02) conducted over the upper Midwest corn and soybean production region of Iowa. Three dates during the period of rapid crops growth (June 23, July 1, and July 8) for which Landsat TM images are available were analyzed. The original pixels were aggregated to form 960 m pixels (to mimic thermal data currently available from MODIS) and were then disaggregated following the procedure suggested by Kustas et al. (2003)* to form 60, 120, and 240 m sub-pixels. LU and FC were obtained at 30 m resolution and then aggregated to 60, 120, 240, and 960 m. The Two-Source-Model was run at each of the resolutions using the pertinent inputs. The model output at 60 m resolution, using the original LST data was considered the base line, to which all other outputs were compared. For comparing the flux results at the lower resolutions, the 60 m flux output was aggregated. The

  8. Ice Thickness Estimation of Thin Sea Ice Using Active Microwave Sensor Data Obtained at Different Frequencies

    NASA Astrophysics Data System (ADS)

    Brath, M.; Kern, S.; Stammer, D.

    2011-12-01

    We present a new approach to estimate thin sea ice thickness based on multi-frequency and multi-angle RADAR backscatter measurements. The method is based on the inversion of a first order backscattering model using Monte Carlo methods without any need for additional measured data than the measured radar cross section (RCS) except an optional guess of the surface temperature. The method is applied to RCS data obtained with the Multi3Scat during August and September 2007 over the Arctic Ocean. The Multi3Scat is a helicopter-borne scatterometer of the University of Hamburg, which simultaneously measures the like-polarization RCS at five different frequencies between 1 GHz and 15 GHz (in frequency bands L, S, C, X, and Ku) at incidence angles of 20° to 65°. A video and an infrared camera simultaneously sense the surface in the scatterometer's footprint for additional, independent information. The uncertainty of the thin sea ice thickness estimates obtained with our method is about 5 cm when combining two or more frequencies but only about 10 cm when using just one frequency. Thin sea ice thickness values obtained with our method are of the same order of independent in-situ observations.

  9. A comparison of maximal bioenergetic enzyme activities obtained with commonly used homogenization techniques.

    PubMed

    Grace, M; Fletcher, L; Powers, S K; Hughes, M; Coombes, J

    1996-12-01

    Homogenization of tissue for analysis of bioenergetic enzyme activities is a common practice in studies examining metabolic properties of skeletal muscle adaptation to disease, aging, inactivity or exercise. While numerous homogenization techniques are in use today, limited information exists concerning the efficacy of specific homogenization protocols. Therefore, the purpose of this study was to compare the efficacy of four commonly used approaches to homogenizing skeletal muscle for analysis of bioenergetic enzyme activity. The maximal enzyme activity (Vmax) of citrate synthase (CS) and lactate dehydrogenase (LDH) were measured from homogenous muscle samples (N = 48 per homogenization technique) and used as indicators to determine which protocol had the highest efficacy. The homogenization techniques were: (1) glass-on-glass pestle; (2) a combination of a mechanical blender and a teflon pestle (Potter-Elvehjem); (3) a combination of the mechanical blender and a biological detergent; and (4) the combined use of a mechanical blender and a sonicator. The glass-on-glass pestle homogenization protocol produced significantly higher (P < 0.05) enzyme activities compared to all other protocols for both enzymes. Of the four protocols examined, the data demonstrate that the glass-on-glass pestle homogenization protocol is the technique of choice for studying bioenergetic enzyme activity in skeletal muscle.

  10. Quantification of the activity of biomolecules in microarrays obtained by direct laser transfer.

    PubMed

    Dinca, V; Ranella, A; Farsari, M; Kafetzopoulos, D; Dinescu, M; Popescu, A; Fotakis, C

    2008-10-01

    The direct-writing technique laser-induced forward transfer has been employed for the micro-array printing of liquid solutions of the enzyme horseradish peroxidase and the protein Titin on nitrocellulose solid surfaces. The effect of two UV laser pulse lengths, femtosecond and nanosecond has been studied in relation with maintaining the activity of the transferred biomolecules. The quantification of the active biomolecules after transfer has been carried out using Bradford assay, quantitative colorimetric enzymatic assay and fluorescence techniques. Spectrophotometric measurements of the HRP and the Titin activity as well as chromatogenic and fluorescence assay studies have revealed a connection between the properties of the deposited, biologically active biomolecules, the experimental conditions and the target composition. The bioassays have shown that up to 78% of the biomolecules remained active after femtosecond laser transfer, while this value reduced to 54% after nanosecond laser transfer. The addition of glycerol in a percentage up to 70% in the solution to be transferred has contributed to the stabilization of the micro-array patterns and the increase of their resolution.

  11. Osteoinductive activity of insulin-functionalized cell culture surfaces obtained using diazonium chemistry

    NASA Astrophysics Data System (ADS)

    Mikulska, Anna; Filipowska, Joanna; Osyczka, Anna; Nowakowska, Maria; Szczubiałka, Krzysztof

    2014-12-01

    Polymeric surfaces suitable for cell culture (DR/Pec) were constructed from diazoresin (DR) and pectin (Pec) in a form of ultrathin films using the layer-by-layer (LbL) technique. The surfaces were functionalized with insulin using diazonium chemistry. Such functionalized surfaces were used to culture human mesenchymal stem cells (hMSCs) to assess their suitability for bone tissue engineering and regeneration. The activity of insulin immobilized on the surfaces (DR/Pec/Ins) was compared to that of insulin dissolved in the culture medium. Human MSC grown on insulin-immobilized DR/Pec surfaces displayed increased proliferation and higher osteogenic activity. The latter was determined by means of alkaline phosphatase (ALP) activity, which increases at early stages of osteoblasts differentiation. Insulin dissolved in the culture medium did not stimulate cell proliferation and its osteogenic activity was significantly lower. Addition of recombinant human bone morphogenetic protein 2 (rhBMP-2) to the culture medium further increased ALP activity in hMSCs indicating additive osteogenic action of immobilized insulin and rhBMP-2

  12. Effects of activation energy and activation volume on the temperature-dependent viscosity of water.

    PubMed

    Kwang-Hua, Chu Rainer

    2016-08-01

    Water transport in a leaf is vulnerable to viscosity-induced changes. Recent research has suggested that these changes may be partially due to variation at the molecular scale, e.g., regulations via aquaporins, that induce reductions in leaf hydraulic conductance. What are the quantitative as well as qualitative changes in temperature-dependent viscosity due to the role of aquaporins in tuning activation energy and activation volume? Using the transition-state approach as well as the boundary perturbation method, we investigate temperature-dependent viscosity tuned by activation energy and activation volume. To validate our approach, we compare our numerical results with previous temperature-dependent viscosity measurements. The rather good fit between our calculations and measurements confirms our present approach. We have obtained critical parameters for the temperature-dependent (shear) viscosity of water that might be relevant to the increasing and reducing of leaf hydraulic conductance. These parameters are sensitive to temperature, activation energy, and activation volume. Once the activation energy increases, the (shear) viscosity of water increases. Our results also show that as the activation volume increases (say, 10^{-23}m^{3}), the (shear) viscosity of water decreases significantly and the latter induces the enhancing of leaf hydraulic conductance. Within the room-temperature regime, a small increase in the activation energy will increase the water viscosity or reduce the leaf hydraulic conductance. Our approach and results can be applied to diverse plant or leaf attributes.

  13. Effects of activation energy and activation volume on the temperature-dependent viscosity of water

    NASA Astrophysics Data System (ADS)

    Kwang-Hua, Chu Rainer

    2016-08-01

    Water transport in a leaf is vulnerable to viscosity-induced changes. Recent research has suggested that these changes may be partially due to variation at the molecular scale, e.g., regulations via aquaporins, that induce reductions in leaf hydraulic conductance. What are the quantitative as well as qualitative changes in temperature-dependent viscosity due to the role of aquaporins in tuning activation energy and activation volume? Using the transition-state approach as well as the boundary perturbation method, we investigate temperature-dependent viscosity tuned by activation energy and activation volume. To validate our approach, we compare our numerical results with previous temperature-dependent viscosity measurements. The rather good fit between our calculations and measurements confirms our present approach. We have obtained critical parameters for the temperature-dependent (shear) viscosity of water that might be relevant to the increasing and reducing of leaf hydraulic conductance. These parameters are sensitive to temperature, activation energy, and activation volume. Once the activation energy increases, the (shear) viscosity of water increases. Our results also show that as the activation volume increases (say, 10-23m3 ), the (shear) viscosity of water decreases significantly and the latter induces the enhancing of leaf hydraulic conductance. Within the room-temperature regime, a small increase in the activation energy will increase the water viscosity or reduce the leaf hydraulic conductance. Our approach and results can be applied to diverse plant or leaf attributes.

  14. Active Control by Conservation of Energy Concept

    NASA Technical Reports Server (NTRS)

    Maestrello, Lucio

    2000-01-01

    Three unrelated experiments are discussed; each was extremely sensitive to initial conditions. The initial conditions are the beginnings of the origins of the information that nonlinearity displays. Initial conditions make the phenomenon unstable and unpredictable. With the knowledge of the initial conditions, active control requires far less power than that present in the system response. The first experiment is on the control of shocks from an axisymmetric supersonic jet; the second, control of a nonlinear panel response forced by turbulent boundary layer and sound; the third, control of subharmonic and harmonics of a panel forced by sound. In all three experiments, control is achieved by redistribution of periodic energy response such that the energy is nearly preserved from a previous uncontrolled state. This type of active control improves the performance of the system being controlled.

  15. Antioxidant activity of fractions from oregano essential oils obtained by molecular distillation.

    PubMed

    Olmedo, Ruben; Nepote, Valeria; Grosso, Nelson Ruben

    2014-08-01

    The objective of this study was to determine the antioxidant activity of fractions separated from oregano essential oil by short-path molecular distillation. Two residue (R1 and R2) and two distillate (D1 and D2) fractions were prepared by molecular distillation. The major components were: carvacrol, terpinen-4-ol and γ-terpinene in R1 and R2; and γ-terpinene, α-terpineol and sabinene in D1 and D2. Free-radical scavenging activity was observed in all fractions and was highest in R2 (77.2%). D1 and D2 showed a smaller amount of volatile oxidation compounds produced from sunflower oil stored at 60°C for 14days. The greatest antioxidant activity was observed in D1 and D2. The thermal stability of oregano essential oil and its fractions was also analysed. R1 and R2 presented an increased carvacrol concentration and thermal stability. The short-path molecular distillation fractions can be used to prepare fractions from oregano essential oil with a higher antioxidant activity.

  16. Origin of activation energy in a superionic conductor.

    PubMed

    Kamishima, O; Kawamura, K; Hattori, T; Kawamura, J

    2011-06-08

    The characteristics of cation diffusion with many-body effects are discussed using Ag β-alumina as an example of a superionic conductor. Polarized Raman spectra of Ag β-alumina have been measured at room temperature. The interatomic potentials were determined by a non-linear least square fitting between the phonon eigenvalues from the Raman observations and a dynamical matrix calculation based on a rigid-ion model. The obtained potential parameters for the model crystal of Ag β-alumina successfully reproduce the macroscopic properties with respect to the heat capacity, isothermal compressibility and self-diffusion constant. A molecular dynamics (MD) calculation has been carried out using the model crystal of Ag β-alumina to understand the many-body effects for the fast ionic diffusion. It was found that the Ag-Ag repulsion by excess Ag defects significantly reduced the cost of the energy difference of the occupancy between the stable and metastable sites. It is possible for the system to take various configurations of the mobile ions through defects easily, and then the fast ionic diffusion will appear. On the other hand, the Ag-Ag repulsion changes the dynamics of the Ag ions from a random hopping to a cooperative motion. In the cooperative motion, the ionic transport becomes difficult due to the additional energy required for the structural relaxation of the surrounding Ag ions. We propose a new insight into the superionic conduction, that is, the activation energy for the ionic transport is composed of two kinds of elements: a 'static' activation energy and a 'dynamic' one. The static activation energy is the cost of the averaged energy difference in the various structural configurations in the equilibrium state. The dynamic activation energy is the additional energy required for the structural relaxation induced by the jump process.

  17. Get Current: Switch on Clean Energy Activity Book

    SciTech Connect

    2014-06-01

    Switching on clean energy technologies means strengthening the economy while protecting the environment. This activity book for all ages promotes energy awareness, with facts on different types of energy and a variety of puzzles in an energy theme.

  18. Human GV oocytes generated by mitotically active germ cells obtained from follicular aspirates

    PubMed Central

    Ding, Xinbao; Liu, Guishu; Xu, Bo; Wu, Changqing; Hui, Ning; Ni, Xin; Wang, Jian; Du, Meirong; Teng, Xiaoming; Wu, Ji

    2016-01-01

    Human female germline stem cells (FGSCs) have opened new opportunities for understanding human oogenesis, delaying menopause, treating infertility, and providing a new strategy for preserving fertility. However, the shortage of adult human ovaries tissues available impedes their future investigations and clinical applications. Here, we have established FGSC lines from scarce ovarian cortical tissues that exist in follicular aspirates (faFGSCs), which are produced and discarded in in vitro fertilization centers worldwide. The faFGSCs have characteristics of germline stem cells involved in the gene expression profile, growth characteristics, and a normal karyotype consistent with that of FGSCs obtained from ovarian cortexes surgically removed from patients (srFGSCs). Furthermore, faFGSCs have developmental potentials including spontaneous differentiation into oocytes under feeder-free conditions, communicating with granulosa cells by gap junctions and paracrine factors, entering meiosis after RA induction, as well as forming follicles after injection into human ovarian cortical tissues xenografted into adult immunodeficient female mice. Lastly, we developed a strategy guiding FGSCs differentiated into germinal vesicle (GV) stage oocytes in vitro and revealed their developmental mechanisms. Our study not only provides a new approach to obtain human FGSCs for medical treatment, but also opens several avenues to investigate human oogenesis in vitro. PMID:27357640

  19. Botanical origin causes changes in nutritional profile and antioxidant activity of fermented products obtained from honey.

    PubMed

    Dezmirean, Graţia I; Mărghitaş, Liviu A; Bobiş, Otilia; Dezmirean, Daniel S; Bonta, Victoriţa; Erler, Silvio

    2012-08-15

    Honey as rich source of enzymatic and nonenzymatic antioxidants serves as health-promoting nutrient in the human body. Here, we present the first time a comparative study of nutritional profiles (e.g., acidities, sugar, organic acid profile, total polyphenolic, flavonoid content) for different unifloral, multifloral honeys and their fermented products, in correlation with their antioxidant activity. Additionally, an optimized method for HPLC separation of organic acids from honey was established. The total phenolic content of honey samples varied widely among the honey types compared to fermented products. High amounts of total flavonoids were quantified in heather honey, followed by raspberry, multifloral, black locust, and linden honey. A positive correlation between the content of polyphenols, flavonoids, and antioxidant activity was observed in honey samples. After fermentation, the flavonoid content of dark honey fermented products decreased significantly. Black locust and linden honeys are more suitable for fermentation because the decrease in antioxidant substances is less pronounced.

  20. Antioxidant and antiproliferative activity of glycosides obtained by biotransformation of xanthohumol.

    PubMed

    Tronina, Tomasz; Bartmańska, Agnieszka; Milczarek, Magdalena; Wietrzyk, Joanna; Popłoński, Jarosław; Rój, Edward; Huszcza, Ewa

    2013-04-01

    The biotransformation of xanthohumol (1), a prenylated chalcone isolated from hops by selected fungi, was investigated. Microbial regioselective glycosylation at the C-4' position led to xanthohumol 4'-O-β-d-glucopyranoside (2) and xanthohumol 4'-O-β-d-(4'''-O-methyl)-glucopyranoside (3). The subsequent cyclization of 2 resulted in isoxanthohumol 7-O-β-glucopyranoside (4). The structures of the products were identified based on spectroscopic methods. The biological activity of isolated metabolites has been evaluated. Compared to xanthohumol (1), metabolite 2 is a better 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenger, while 2 and 3 have stronger antiproliferative activity against the human HT-29 colon cancer cell line.

  1. Topography of Photosynthetic Activity of Leaves Obtained from Video Images of Chlorophyll Fluorescence 1

    PubMed Central

    Daley, Paul F.; Raschke, Klaus; Ball, J. Timothy; Berry, Joseph A.

    1989-01-01

    The distribution of photosynthetic activity over the area of a leaf and its change with time was determined (at low partial pressure of O2) by recording images of chlorophyll fluorescence during saturating light flashes. Simultaneously, the gas exchange was being measured. Reductions of local fluorescence intensity quantitatively displayed the extent of nonphotochemical quenching; quench coefficients, qN, were computed pixel by pixel. Because rates of photosynthetic electron transport are positively correlated with (1 − qN), computed images of (1 − qN) represented topographies of photosynthetic activity. Following application of abscisic acid to the heterobaric leaves of Xanthium strumarium L., clearly delineated regions varying in nonphotochemical quenching appeared that coincided with areoles formed by minor veins and indicated stomatal closure in groups. Images Figure 2 Figure 4 Figure 6 PMID:16666912

  2. Fluorescence resonance energy-transfer affects the determination of the affinity between ligand and proteins obtained by fluorescence quenching method

    NASA Astrophysics Data System (ADS)

    Xiao, Jianbo; Wei, Xinlin; Wang, Yuanfeng; Liu, Chunxi

    2009-11-01

    The interaction between esculin and serum albumins was investigated to illustrate that the fluorescence resonance energy-transfer (FRET) affects the determination of the binding constants obtained by fluorescence quenching method. The binding constants ( Ka) obtained by the double-logarithm curve for esculin-BSA and esculin-HSA were 1.02 × 10 7 and 2.07 × 10 4 L/mol, respectively. These results from synchronous fluorescence showed that the Tyr and Trp residues of HSA were affected more deeply than those in BSA. The excitation profile of esculin showed that in the presence of BSA and HSA, the S 0 → S 1 transition of esculin ( λexmax≈340 nm) appears, which is similar to the λemmax of BSA and HSA. The critical distance ( R0) between BSA and esculin is higher than that of HSA, which showed that the affinity of esculin and HSA should be higher than that of BSA. After centrifugation, the concentrations of esculin bound to albumins were determined by means of the fluorescence of esculin. It was found that much more esculin was bound to HSA than to BSA. However, the bound models for BSA and HSA are almost the same. The concentration of esculin bound to serum albumin at first decreased with the addition of esculin and then increased. From above results, it can be concluded that the affinity of esculin and HSA should be higher than that of esculin and BSA. This example showed that in the presence of FRET, the binding constants between ligands and proteins based on fluorescence quenching might be deviated.

  3. Novel polyacetylene derivatives and their inhibitory activities on acetylcholinesterase obtained from Panax ginseng roots.

    PubMed

    Murata, Kazuya; Iida, Daiki; Ueno, Yoshihiro; Samukawa, Keiichi; Ishizaka, Toshihiko; Kotake, Takeshi; Matsuda, Hideaki

    2017-01-01

    In our research program to identify cholinesterase and β-secretase inhibitors, we investigated Ginseng (root of Panax ginseng), a crude drug described as a multifunctional drug in the ancient Chinese herbal book Shennong Ben Cao Jing. Results from hexane and methanol extracts showed moderate inhibitory activities. This suggests that ginseng roots may be effective for the prevention of and therapy for dementia. We then focused on hexane extracts of raw ginseng root and dried ginseng root since the determination of hexane extract constituents has not been studied extensively. Activity-guided fractionation and purification led to the isolation of 4 polyacetylene compounds; homopanaxynol, homopanaxydol, (9Z)-heptadeca-1, 9-diene-4,6-diyn-3-one, and (8E)-octadeca-1,8-diene-4,6-diyn-3,10-diol. The chemical structures of these compounds, including stereochemistry, were determined. This is the first study to identify the structure of homopanaxynol and homopanaxydol. Moreover, the modes of action of some compounds were characterized as competitive inhibitors. This study showed, for the first time, that polyacetylene compounds possess acetylcholinesterase inhibitory activities.

  4. Biomass based activated carbon obtained from sludge and sugarcane bagasse for removing lead ion from wastewater.

    PubMed

    Tao, Hu-Chun; Zhang, He-Ran; Li, Jin-Bo; Ding, Wen-Yi

    2015-09-01

    Sewage sludge and bagasse were used as raw materials to produce cheap and efficient adsorbent with great adsorption capacity of Pb(2+). By pyrolysis at 800 °C for 0.5 h, the largest surface area (806.57 m(2)/g) of the adsorbent was obtained, enriched with organic functional groups. The optimal conditions for production of the adsorbent and adsorption of Pb(2+) were investigated. The results of adsorb-ability fitted the Langmuir isotherm and pseudo-second-order model well. The highest Pb(2+) (at pH = 4.0) adsorption capacity was achieved by treating with 60% (v/v) HNO3. This is a promising approach for metal removal from wastewater, as well as recycling sewage sludge and bagasse to ease their disposal pressure.

  5. Antioxidant Activity and Characterization of One New Polysaccharide Obtained from Perigord Truffle (Tuber huidongense)

    PubMed Central

    Chen, Yong-Feng; Jiang, Wen-wen; Zhang, Shi-qi; Liang, Yong

    2016-01-01

    As a medicinal and edible fungus parasitizing on the trees, Perigord Truffle (Tuber huidongense) is well known for its delicious taste, unique smell, and high medical value for healthcare. One new water-soluble nonstarch polysaccharide (PST-W with the yield of 0.41%) from Perigord Truffle (Tuber huidongense) was purified and identified on structural characteristics for the first time. The characterizations of PST-W were studied on physicochemical properties, main components of monosaccharide(s), and molecular structure. The monosaccharide compositions of PST-W were studied and identified as glucan, only containing D-glucoses with the molecular structure of [→6) α-D-Glcp (1 → 6)  α-D-Glcp (1→]n by methylation analysis and NMR. In the determination of total reducing capacity, the reducing abilities of polysaccharide extracts could be listed as vitamin C > PST-W > crude polysaccharides-3 > crude polysaccharides-2 > crude polysaccharides-1. All of PST-W, crude polysaccharides-2, and crude polysaccharides-3 were relatively good scavenger for 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radicals with IC50 of 2.81, 4.17, and 3.44 mg/mL, respectively. However, O2−∙ clearing abilities of PST-W and crude polysaccharides were obviously weaker. The activities of total crude extract were the worst, indicating that the impurities might negatively affect the antioxidant activity. Thus, the separation and purification of polysaccharides were significant to increase the antioxidant activity in some degree. PMID:27446223

  6. Antioxidant Activity and Characterization of One New Polysaccharide Obtained from Perigord Truffle (Tuber huidongense).

    PubMed

    Chen, Yong-Feng; Jiang, Wen-Wen; Zhang, Shi-Qi; Kan, Jian-Quan; Liang, Yong

    2016-01-01

    As a medicinal and edible fungus parasitizing on the trees, Perigord Truffle (Tuber huidongense) is well known for its delicious taste, unique smell, and high medical value for healthcare. One new water-soluble nonstarch polysaccharide (PST-W with the yield of 0.41%) from Perigord Truffle (Tuber huidongense) was purified and identified on structural characteristics for the first time. The characterizations of PST-W were studied on physicochemical properties, main components of monosaccharide(s), and molecular structure. The monosaccharide compositions of PST-W were studied and identified as glucan, only containing D-glucoses with the molecular structure of [→6) α-D-Glcp (1 → 6)  α-D-Glcp (1→] n by methylation analysis and NMR. In the determination of total reducing capacity, the reducing abilities of polysaccharide extracts could be listed as vitamin C > PST-W > crude polysaccharides-3 > crude polysaccharides-2 > crude polysaccharides-1. All of PST-W, crude polysaccharides-2, and crude polysaccharides-3 were relatively good scavenger for 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radicals with IC50 of 2.81, 4.17, and 3.44 mg/mL, respectively. However, O2 (-∙) clearing abilities of PST-W and crude polysaccharides were obviously weaker. The activities of total crude extract were the worst, indicating that the impurities might negatively affect the antioxidant activity. Thus, the separation and purification of polysaccharides were significant to increase the antioxidant activity in some degree.

  7. Energy and Man's Environment Activity Guide: An Interdisciplinary Teacher's Guide to Energy and Environmental Activities, Section One - Sources of Energy.

    ERIC Educational Resources Information Center

    Jones, John, Ed.

    This publication presents the activities pertaining to the first goal of this activity guide series. The activities in this publication focus primarily on the availability of resources, forms of energy, natural laws, and socioeconomic considerations. These materials are appropriate for middle school and junior high school students. These…

  8. Energy and Man's Environment Activity Guide: An Interdisciplinary Teacher's Guide to Energy and Environmental Activities, Section Four - Impacts of Energy.

    ERIC Educational Resources Information Center

    Jones, John, Ed.

    This publication presents the activities pertaining to the fourth goal of this activity guide series. The activities in this publication focus on the socioeconomic effects of energy uses and crises and the understandings needed to assess those effects. These materials are appropriate for middle school and junior high school students. These…

  9. Antithrombotic activity of fractions and components obtained from raspberry leaves (Rubus chingii).

    PubMed

    Han, Na; Gu, Yuhong; Ye, Chun; Cao, Yan; Liu, Zhihui; Yin, Jun

    2012-05-01

    The 70% ethanol fraction from an aqueous extract of raspberry leaves was shown to be the most antithrombotic fraction in in vitro and in vivo tests. The total flavonoids and phenolics in this fraction were 0.286g/g and 0.518g/g by colorimetry. Six compounds, including salicylic acid, kaempferol, quercetin, tiliroside, quercetin 3-O-β-d-glucopyranoside and kaempferol 3-O-β-d-glucopyranoside, were isolated from the active fraction. Among them, kaempferol, quercetin and tiliroside obviously delayed plasma recalcification time (PRT) in blood.

  10. INVESTIGATION OF FLY ASH AND ACTIVATED CARBON OBTAINED FROM PULVERIZED COAL BOILERS

    SciTech Connect

    Edward K. Levy; Christopher Kiely

    2005-11-01

    One of the techniques for Hg capture in coal-fired boilers involves injection of activated carbon (AC) into the boiler downstream of the air preheater. Hg is adsorbed onto the AC particles and fly ash, which are then both removed in an electrostatic precipitator or baghouse. This project addresses the issues of Hg on activated carbon and on fly ash from a materials re-use point of view. It also addresses the possible connection between SCR reactors, fly ash properties and Hg capture. The project is determining the feasibility of separating AC from fly ash in a fluidized bed and of regenerating the separated AC by heating the AC to elevated temperatures in a fluidized bed. The temperatures needed to drive off the Hg from the ash in a fluidized bed are also being determined. Finally, samples of fly ash from power plants with SCR reactors for NO{sub x} control, are being analyzed to determine the effect of SCR on the ash.

  11. Investigation of Fly Ash and Activated Carbon Obtained from Pulverized Coal Boilers

    SciTech Connect

    Edward K. Levy; Christopher Kiely; Zheng Yao

    2006-08-31

    One of the techniques for Hg capture in coal-fired boilers involves injection of activated carbon (AC) into the boiler downstream of the air preheater. Hg is adsorbed onto the AC particles and fly ash, which are then both removed in an electrostatic precipitator or baghouse. This project addressed the issues of Hg on activated carbon and on fly ash from a materials re-use point of view. It also addressed the possible connection between SCR reactors, fly ash properties and Hg capture. The project has determined the feasibility of separating AC from fly ash in a fluidized bed and of regenerating the separated AC by heating the AC to elevated temperatures in a fluidized bed. The temperatures needed to drive off the Hg from the ash in a fluidized bed have also been determined. Finally, samples of fly ash from power plants with SCR reactors for NO{sub x} control have been analyzed in an effort to determine the effects of SCR on the ash.

  12. INVESTIGATION OF FLY ASH AND ACTIVATED CARBON OBTAINED FROM PULVERIZED COAL BOILERS

    SciTech Connect

    Edward K. Levy; Christopher Kiely

    2004-11-01

    One of the techniques for Hg capture in coal-fired boilers involves injection of activated carbon (AC) into the boiler downstream of the air preheater. Hg is adsorbed onto the AC particles and fly ash, which are then both removed in an electrostatic precipitator or baghouse. This project addresses the issues of Hg on activated carbon and on fly ash from a materials re-use point of view. It also addresses the possible connection between SCR reactors, fly ash properties and Hg capture. The project is determining the feasibility of separating AC from fly ash in a fluidized bed and of regenerating the separated AC by heating the AC to elevated temperatures in a fluidized bed. The temperatures needed to drive off the Hg from the ash in a fluidized bed are also being determined. Finally, samples of fly ash from power plants with SCR reactors for NO{sub x} control, are being analyzed to determine the effect of SCR on the ash. These analyses will also determine the properties of ash which are important for Hg capture.

  13. Polyphenol-Retaining Decaffeinated Cocoa Powder Obtained by Supercritical Carbon Dioxide Extraction and Its Antioxidant Activity.

    PubMed

    Kobori, Kinji; Maruta, Yuto; Mineo, Shigeru; Shigematsu, Toru; Hirayama, Masao

    2013-10-14

    Cocoa beans contain many functional ingredients such as theobromine and polyphenols, but also contain a relatively high amount of caffeine, which can negatively impact human health. It is therefore desirable to reduce caffeine levels in cocoa powder used to make chocolate or cocoa beverages while retaining functional ingredients. We have established conditions for supercritical carbon dioxide (SCCO₂) extraction that remove 80.1% of the caffeine from cocoa powder while retaining theobromine (94.1%) and polyphenols (84.7%). The antioxidant activity of the decaffeinated cocoa powder (DCP) made with this optimized SCCO₂ extraction method was 85.3% that of non-processed cocoa powder. The total procyanidin and total polyphenol concentrations of the DCPs resulting from various SCCO₂ extractions showed a significant positive correlation with oxygen radical absorbance capacity (ORAC). The correlation coefficient between total polyphenols and ORAC was higher than that between total procyanidins and ORAC; thus, the concentration of total polyphenols might be a greater factor in the antioxidant activity of DCP. These results indicate that we could remove large quantities of caffeine from conventional high-cocoa products while retaining the functional benefits of high polyphenol content. This SCCO₂ extraction method is expected to be applicable high-cocoa products, such as dark chocolate.

  14. Polyphenol-Retaining Decaffeinated Cocoa Powder Obtained by Supercritical Carbon Dioxide Extraction and Its Antioxidant Activity

    PubMed Central

    Kobori, Kinji; Maruta, Yuto; Mineo, Shigeru; Shigematsu, Toru; Hirayama, Masao

    2013-01-01

    Cocoa beans contain many functional ingredients such as theobromine and polyphenols, but also contain a relatively high amount of caffeine, which can negatively impact human health. It is therefore desirable to reduce caffeine levels in cocoa powder used to make chocolate or cocoa beverages while retaining functional ingredients. We have established conditions for supercritical carbon dioxide (SCCO2) extraction that remove 80.1% of the caffeine from cocoa powder while retaining theobromine (94.1%) and polyphenols (84.7%). The antioxidant activity of the decaffeinated cocoa powder (DCP) made with this optimized SCCO2 extraction method was 85.3% that of non-processed cocoa powder. The total procyanidin and total polyphenol concentrations of the DCPs resulting from various SCCO2 extractions showed a significant positive correlation with oxygen radical absorbance capacity (ORAC). The correlation coefficient between total polyphenols and ORAC was higher than that between total procyanidins and ORAC; thus, the concentration of total polyphenols might be a greater factor in the antioxidant activity of DCP. These results indicate that we could remove large quantities of caffeine from conventional high-cocoa products while retaining the functional benefits of high polyphenol content. This SCCO2 extraction method is expected to be applicable high-cocoa products, such as dark chocolate. PMID:28239130

  15. Antioxidant activities of a polyglucuronic acid sodium salt obtained from TEMPO-mediated oxidation of xanthan.

    PubMed

    Delattre, C; Pierre, G; Gardarin, C; Traikia, M; Elboutachfaiti, R; Isogai, A; Michaud, P

    2015-02-13

    A xanthouronic acid sodium salt called xanthouronan was produced from xanthan by regioselective oxidation with NaOCl/NaBr using 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO) as catalyst. The efficiency of the one pot TEMPO-mediated oxidation was confirmed by HPAEC-PAD, (13)C NMR, and FT-IR. The oxidation degree was close to 98% and the mass yield of this new polyglucuronic acid was higher than 90% (w/w). The macromolecular characterization of xanthouronan using SEC-MALLS showed a molecular size reduced by a third due to the oxidation treatment and the degree of polymerization (DP) of the xanthouronan form was about 665. The evaluation of the enzymatic degradation of this C-6 carboxylated xanthan by various polysaccharide hydrolases and one polysaccharide lyase showed its high resistant to biodegradation. The antioxidant activity of xanthouronan was also tested by using the 2,2'-diphenyl-1-picrylhydrazyle (DPPH) and hydroxyl radical procedures. At 1 g/L, xanthouronan presented 75% of the ascorbic acid antioxidant activity.

  16. Hydrogen Energy Storage (HES) Activities at NREL; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    Eichman, J.

    2015-04-21

    This presentation provides an overview of hydrogen and energy storage, including hydrogen storage pathways and international power-to-gas activities, and summarizes the National Renewable Energy Laboratory's hydrogen energy storage activities and results.

  17. Assessment of Parasitic Activity of Fusarium Strains Obtained from a Heterodera schachtii-Suppressive Soil

    PubMed Central

    Gao, Xuebiao; Yin, Bei; Borneman, James; Becker, J. Ole

    2008-01-01

    This study assessed the potential impact of various Fusarium strains on the population development of sugarbeet cyst nematodes. Fungi were isolated from cysts or eggs of Heterodera schachtii Schmidt that were obtained from a field suppressive to that nematode. Twenty-six strains of Fusarium spp. were subjected to a phylogenic analysis of their rRNA-ITS nucleotide sequences. Seven genetically distinct Fusarium strains were evaluated for their ability to influence population development of H. schachtii and crop performance in greenhouse trials. Swiss chard (Beta vulgaris) seedlings were transplanted into fumigated field soil amended with a single fungal strain at 1,000 propagules/g soil. One week later, the soil was infested with 250 H. schachtii J2/100 cm3 soil. Parasitized eggs were present in all seven Fusarium treatments at 1,180 degree-days after fungal infestation. The percentage of parasitism ranged from 17 to 34%. Although the most efficacious F. oxysporum strain 471 produced as many parasitized eggs as occurred in the original suppressive soil, none of the Fusarium strains reduced the population density of H. schachtii compared to the conducive check. This supports prior results that Fusarium spp. were not the primary cause of the population suppression of sugarbeet cyst nematodes at this location. PMID:19259511

  18. ERP Energy and Cognitive Activity Correlates

    NASA Astrophysics Data System (ADS)

    Schillaci, Michael Jay; Vendemia, Jennifer M. C.

    2014-03-01

    We propose a novel analysis approach for high-density event related scalp potential (ERP) data where the integrated channel-power is used to attain an energy density functional state for channel-clusters of neurophysiological significance. The method is applied to data recorded during a two-stimulus, directed lie paradigm and shows that deceptive responses emit between 8% and 10% less power. A time course analysis of these cognitive activity measures over posterior and anterior regions of the cortex suggests that neocortical interactions, reflecting the differing workload demands during executive and semantic processes, take about 50% longer for the case of deception. These results suggest that the proposed method may provide a useful tool for the analysis of ERP correlates of high-order cognitive functioning. We also report on a possible equivalence between the energy functional distribution and near-infrared signatures that have been measured with other modalities.

  19. New electrochemical procedure for obtaining surface enhanced Raman scattering active polythiophene films on platinum

    NASA Astrophysics Data System (ADS)

    Bazzaoui, E. A.; Aeiyach, S.; Aubard, J.; Felidj, N.; Lévi, G.; Sakmeche, N.; Lacaze, P. C.

    1998-06-01

    A new electrochemical procedure for obtaining Surface Enhanced Raman Scattering (SERS) spectra of silver islands polybithiophene composite films is described. During the electropolymerization process which consists to use silver dodecylsulfate micellar aqueous solution mixed with bithiophene and LiClO4, silver cations are reduced, thus giving metallic silver particles embedded within the polybithiophene (PbT) film. Both doped and undoped PbT species display SERS spectra with exaltation factors varying between 40 and 200 with respect to the film prepared in sodium dodecylsulfate. Vibrational characterization of both doped and undoped species show that the amount of the polymer structural defects are more important in the oxidized species than in the reduced ones. This general method allows to synthesize various polymeric films displaying SERS effect and appears very promising for the structural study of these materials. Nous décrivons un procédé original pour synthétiser par voie électrochimique des films formés d'un composite de polybithiophène et d'îlots d'argent qui présentent des Spectres de Diffusion Raman Exaltée de Surface (DRES). Au cours de l'électropolymérisation d'une solution aqueuse micellaire de bithiophène en présence de dodécylsulfate d'argent (AgDS) et de LiClO4, les ions argent présents dans la solution se complexent avec le soufre du bithiophène et pénètrent dans le film polymère où ils sont réduits sous forme d'argent métallique. Les spectres Raman des deux formes réduite et oxydée du film ainsi obtenu présentent un effet DRES important avec un facteur d'exaltation variant entre 40 et 200 par rapport au même film électrosynthétisé en présence de dodécylsulfate de sodium (SDS). L'analyse vibrationnelle des deux formes redox montre que le taux de défauts est plus important dans la forme oxydée que dans la forme réduite. Cette méthode de polymérisation très générale, qui permet d'obtenir des polymères

  20. 25 CFR 162.539 - Must I obtain a WEEL before obtaining a WSR lease?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... AND PERMITS Wind and Solar Resource Leases Wsr Leases § 162.539 Must I obtain a WEEL before obtaining... direct result of energy resource information gathered from a WEEL activity, obtaining a WEEL is not...

  1. Active tectonic deformation along rejuvenated faults in tropical Borneo: Inferences obtained from tectono-geomorphic evaluation

    NASA Astrophysics Data System (ADS)

    Mathew, Manoj Joseph; Menier, David; Siddiqui, Numair; Kumar, Shashi Gaurav; Authemayou, Christine

    2016-08-01

    active folding of the Rajang Group fold-thrust belt to present and these events reactivated old major faults and minor related dislocations. From geomorphic analysis associated with sedimentary record, we posit that the terrain could have undergone high uplift rates since 5 Ma or multi-phased uplift with periodic intermittent pulses of high and low uplift rates.

  2. Energy and power limits for microbial activity

    NASA Astrophysics Data System (ADS)

    LaRowe, D.; Amend, J.

    2014-12-01

    The goal of this presentation is to describe a quantitative framework for determining how energy limits microbial activity, biomass and, ultimately, biogeochemical processes. Although this model can be applied to any environment, its utility is demonstrated in marine sediments, which are an attractive test habitat because they encompass a broad spectrum of energy levels, varying amounts of biomass and are ubiquitous. The potential number of active microbial cells in Arkonas Basin (Baltic Sea) sediments are estimated as a function of depth by quantifying the amount of energy that is available to them and the rate at which it is supplied: power. The amount of power supplied per cubic centimeter of sediment is determined by calculating the Gibbs energy of fermentation and sulfate reduction in combination with the rate of particulate organic carbon, POC, degradation. The Reactive Continuum Model (Boudreau and Ruddick, 1991), RCM, is used to determine the rate at which POC is made available for microbial consumption. The RCM represents POC as containing a range of different types of organic compounds whose ability to be consumed by microorganisms varies as a function of the age of the sediment and on the distribution of compound types that were initially deposited. The sediment age model and RCM parameters determined by (Mogollon et al., 2012) are used. The power available for fermentation and sulfate reduction coupled to H2 and acetate oxidation varies from 10-8 W cm-3 at the sediment water interface to between 10-11 - 10-12 W cm-3 at 3.5 meters below the seafloor, mbsf. Using values of maintenance powers for each of these catabolic activities taken from the literature, the total number of active cells in these sediments similarly decreases from just less than 108 cell cm-3 at the SWI to 4.6 x 104 cells cm-3 at 3.5 mbsf. The number of moles of POC decreases from 2.6 x 10-5 to 9.5 x 10-6, also becoming more recalcitrant with depth. Boudreau, B. P. and Ruddick, B. R

  3. Upgrading the rice husk char obtained by flash pyrolysis for the production of amorphous silica and high quality activated carbon.

    PubMed

    Alvarez, Jon; Lopez, Gartzen; Amutio, Maider; Bilbao, Javier; Olazar, Martin

    2014-10-01

    The overall valorization of rice husk char obtained by flash pyrolysis in a conical spouted bed reactor (CSBR) has been studied in a two-step process. Thus, silica has been recovered in a first step and the remaining carbon material has been subjected to steam activation. The char samples used in this study have been obtained by continuous flash pyrolysis in a conical spouted bed reactor at 500°C. Extraction with Na2CO3 allows recovering 88% of the silica contained in the rice husk char. Activation of the silica-free rice husk char has been carried out in a fixed bed reactor at 800°C using steam as activating agent. The porous structure of the activated carbons produced includes a combination of micropores and mesopores, with a BET surface area of up to 1365m(2)g(-1) at the end of 15min.

  4. Science. Iowa Developed Energy Activity Sampler, 6-12. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines. Div. of Instructional Services.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This document is one of a series of revised IDEAS booklets, and provides activities for teaching science. The activities are intended to present energy principles in an interesting manner…

  5. Mathematics. Iowa Developed Energy Activity Sampler, 6-12. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This document is one of the series of revised IDEAS booklets, and provides activities for teaching mathematics. The activities are intended to present energy principles in an interesting…

  6. Science. Iowa Developed Energy Activity Sampler, 6-12. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This document is one of the series of revised IDEAS booklets, and provides activities for teaching science. The activities are intended to present energy principles in an interesting manner…

  7. Energy Adventure Center. Activity Book. Revised [and Expanded] Edition.

    ERIC Educational Resources Information Center

    Wichita Unified School District 259, KS.

    A variety of energy activities are provided, including instructions for and questions related to energy films. The activities are organized into five sections. Section 1 (work) includes an activity focusing on movement and change. Section 2 (forms of energy) includes activities related to mechanical (movement), radiant (light), chemical (burning),…

  8. Modeling of moisture diffusivity, activation energy and energy consumption in fluidized bed drying of rough rice

    NASA Astrophysics Data System (ADS)

    Khanali, Majid; Banisharif, Alireza; Rafiee, Shahin

    2016-11-01

    The present work was an attempt to assess the effective moisture diffusivity, activation energy, and energy consumption of rough rice in a batch fluidized bed dryer. Drying experiments were conducted at drying air temperatures of 50, 60, and 70 °C, superficial fluidization velocities of 2.3, 2.5, and 2.8 m/s, and solids holdup of 1.32 kg. Drying kinetics showed that the whole fluidized bed drying of rough rice occurred in the falling rate period. The effective moisture diffusivity was described by an Arrhenius equation. The evaluated effective moisture diffusivity increased with drying air temperature and superficial fluidization velocity and was found to vary from 4.78 × 10-11 to 1.364 × 10-10 m2/s with R2 higher than 0.9643. The activation energy and the pre-exponential factor of Arrhenius equation were found to be in the range of 36.59-44.31 kJ/mol and 4.71 × 10-5-7.15 × 10-4 m2/s, respectively. Both maximum values of the specific energy consumption of 74.73 MJ/kg and the total energy need of 12.43 MJ were obtained at 60 °C drying air temperature and 2.8 m/s superficial fluidization velocity. Both minimum values of the specific energy consumption of 29.98 MJ/kg and the total energy need of 4.85 MJ were obtained under drying air temperature of 70 °C and superficial fluidization velocity of 2.3 m/s.

  9. Chemical Treatment of US Department of Energy High Level and Low Level Waste to Obtain a Pure Radiochemical Fraction for Determination of Californium Alpha-Decay Content

    SciTech Connect

    Dewberry, R.

    2002-12-02

    We have developed a chemical separation technique that allows the radiochemical determination of the californium a-decay content in Department of Energy (DOE) high level wastes from the Hanford and Savannah River sites. The chemical separation technique uses a series of column extraction chromatography steps that use Eichrom Industries' lanthanide and actinide plus 3 oxidation state selective Ln-resin(R) and the transuranic selective plus 4 oxidation state TRU-resin(R) to obtain intermediate product phases in dilute nitric acid. The technique has been demonstrated on three types of authentic DOE high and low level waste samples. We obtain discrimination from Pu a-activity by a factor of over 200 and from Cm-244 a-activity by a factor approaching 1700. Californium recoveries are measured by addition of a Cf-249 spike and are in the range of 50 percent to 90 percent in the synthetic samples and are in the range of 1.4 percent to 48 percent for the authentic DOE waste samples.

  10. Simultaneous determination of interfacial energy and growth activation energy from induction time measurements

    NASA Astrophysics Data System (ADS)

    Shiau, Lie-Ding; Wang, Hsu-Pei

    2016-05-01

    A model is developed in this work to calculate the interfacial energy and growth activation energy of a crystallized substance from induction time data without the knowledge of the actual growth rate. Induction time data for αL-glutamic acid measured with a turbidity probe for various supersaturations at temperatures from 293 to 313 K are employed to verify the developed model. In the model a simple empirical growth rate with growth order 2 is assumed because experiments are conducted at low supersaturation. The results indicate for αL-glutamic acid that the growth activation energy is 39 kJ/mol, which suggests that the growth rate of small nuclei in the agitated induction time experiments is integration controlled. The interfacial energy obtained from the current model is in the range of 5.2-7.4 mJ/m2, which is slightly greater than that obtained from the traditional method (ti-1∝J) for which the value is in the range 4.1-5.7 mJ/m2.

  11. Activation energy for a model ferrous-ferric half reaction from transition path sampling

    NASA Astrophysics Data System (ADS)

    Drechsel-Grau, Christof; Sprik, Michiel

    2012-01-01

    Activation parameters for the model oxidation half reaction of the classical aqueous ferrous ion are compared for different molecular simulation techniques. In particular, activation free energies are obtained from umbrella integration and Marcus theory based thermodynamic integration, which rely on the diabatic gap as the reaction coordinate. The latter method also assumes linear response, and both methods obtain the activation entropy and the activation energy from the temperature dependence of the activation free energy. In contrast, transition path sampling does not require knowledge of the reaction coordinate and directly yields the activation energy [C. Dellago and P. G. Bolhuis, Mol. Simul. 30, 795 (2004), 10.1080/08927020412331294869]. Benchmark activation energies from transition path sampling agree within statistical uncertainty with activation energies obtained from standard techniques requiring knowledge of the reaction coordinate. In addition, it is found that the activation energy for this model system is significantly smaller than the activation free energy for the Marcus model, approximately half the value, implying an equally large entropy contribution.

  12. Anti-microbial activity and anti-complement activity of extracts obtained from selected Hawaiian medicinal plants.

    PubMed

    Locher, C P; Burch, M T; Mower, H F; Berestecky, J; Davis, H; Van Poel, B; Lasure, A; Vanden Berghe, D A; Vlietinck, A J

    1995-11-17

    Selected plants having a history of use in Polynesian traditional medicine for the treatment of infectious disease were investigated for anti-viral, anti-fungal and anti-bacterial activity in vitro. Extracts from Scaevola sericea, Psychotria hawaiiensis, Pipturus albidus and Eugenia malaccensis showed selective anti-viral activity against Herpes Simplex Virus-1 and 2 and Vesicular Stomatitis Virus. Aleurites moluccana extracts showed anti-bacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa, while Pipturus albidus and Eugenia malaccensis extracts showed growth inhibition of Staphylococcus aureus and Streptococcus pyogenes. Psychotria hawaiiensis and Solanum niger inhibited growth of the fungi Microsporum canis, Trichophyton rubrum and Epidermophyton floccosum, while Ipomoea sp., Pipturus albidus, Scaevola sericea, Eugenia malaccensis, Piper methysticum, Barringtonia asiatica and Adansonia digitata extracts showed anti-fungal activity to a lesser extent. Eugenia malaccensis was also found to inhibit the classical pathway of complement suggesting that an immunological basis for its in vivo activity was identified. This study has confirmed some of the ethnobotanical reports of Hawaiian medicinal plants having curative properties against infections using biological assays in vitro.

  13. Distributed Energy Communications & Controls, Lab Activities - Summary

    SciTech Connect

    Rizy, D Tom

    2010-01-01

    The purpose is to develop controls for inverter-based renewable and non-renewable distributed energy systems to provide local voltage, power and power quality support for loads and the power grid. The objectives are to (1) develop adaptive controls for inverter-based distributed energy (DE) systems when there are multiple inverters on the same feeder and (2) determine the impact of high penetration high seasonal energy efficiency ratio (SEER) air conditioning (A/C) units on power systems during sub-transmission faults which can result in an A/C compressor motor stall and assess how inverter-based DE can help to mitigate the stall event. The Distributed Energy Communications & Controls Laboratory (DECC) is a unique facility for studying dynamic voltage, active power (P), non-active power (Q) and power factor control from inverter-based renewable distributed energy (DE) resources. Conventionally, inverter-based DE systems have been designed to provide constant, close to unity power factor and thus not provide any voltage support. The DECC Lab interfaces with the ORNL campus distribution system to provide actual power system testing of the controls approach. Using mathematical software tools and the DECC Lab environment, we are developing and testing local, autonomous and adaptive controls for local voltage control and P & Q control for inverter-based DE. We successfully tested our active and non-active power (P,Q) controls at the DECC laboratory along with voltage regulation controls. The new PQ control along with current limiter controls has been tested on our existing inverter test system. We have tested both non-adaptive and adaptive control modes for the PQ control. We have completed several technical papers on the approaches and results. Electric power distribution systems are experiencing outages due to a phenomenon known as fault induced delayed voltage recovery (FIDVR) due to air conditioning (A/C) compressor motor stall. Local voltage collapse from FIDVR is

  14. 76 FR 55278 - Assistance to Foreign Atomic Energy Activities

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-07

    ...; ] DEPARTMENT OF ENERGY 10 CFR Part 810 RIN 1994-AA02 Assistance to Foreign Atomic Energy Activities AGENCY.... SUMMARY: DOE proposes to amend its regulation concerning unclassified assistance to foreign atomic energy... territories for which a general authorization for foreign atomic energy activities is available. This...

  15. Ex vivo digestion of carp muscle tissue--ACE inhibitory and antioxidant activities of the obtained hydrolysates.

    PubMed

    Borawska, J; Darewicz, M; Vegarud, G E; Iwaniak, A; Minkiewicz, P

    2015-01-01

    In the digestive tract of humans, bioactive peptides, i.e. protein fragments impacting the physiological activity of the body, may be released during the digestion of food proteins, including those of fish. The aim of the study was to establish the method of human ex vivo digestion of carp muscle tissue and evaluate the angiotensin I-converting enzyme inhibitory and antioxidant activities of hydrolysates obtained after digestion. It was found that the hydrolysates of carp muscle tissue obtained with the three-stage method of simulated ex vivo digestion showed ACE inhibitory as well as antioxidative activities. It was demonstrated that the degree of hydrolysis depended on the duration of individual stages and the degree of comminution of the examined material. Although the applied gastric juices initiated the process of hydrolysis of carp muscle tissue, the duodenal juices caused a rapid increase in the amount of hydrolysed polypeptide bonds. The antihypertensive and antioxidative activities of the hydrolysates of carp muscle tissue increased together with progressive protein degradation. However, the high degree of protein hydrolysis does not favour an increase in the activity of free radical scavenging. The presented results are an example of the first preliminary screening of the potential health-promoting biological activity of carp muscle tissue in an ex vivo study.

  16. [Hypoglycemic activity of berberin and extract obtained from the bark of Phellodendron lavalei, introduced in sub tropic areas of Georgia].

    PubMed

    2010-01-01

    The goal of this study was to evaluate hypoglycemic activity of Berberin and extract obtained from the bark of Phellodendron Lavalei, which is introduced in sub tropic areas of Georgia-Kobuleti. The study was carried out to reveal comparative hypoglycemic activity and acute toxicity of alkaloid Berberin and bark extract of Phellodendron Lavalei. Effects of Berberin hydrochloride and bark extract on blood glucose level was studied on mice. Measurement of blood glucose level was carried out on fasting animals using glucose meter "GlucoLab"--auto-coding. The study showed that Berberin hydrochloride dose 150 mg/kg, extract (obtained from the bark of Phellodendron Lavalei) dose 400 mg/kg and glybenclamid dose 0.25 mg/kg practically decreased blood glucose level of mice in a same pattern. Received data allows us to suggest that Phellodendron Lavalei, introduced in sub tropic areas of Georgia contains active hypoglycemic components. In conclusion the possible use of Phellodendron Lavalei as a plant raw material for obtaining hypoglycemic substances needs to be decided after further study of efficacy, mechanism of action of extracts and active components of Phellodendron Lavalei on experimental models of diabetes mellitus.

  17. Effective atomic numbers of blue topaz at different gamma-rays energies obtained from Compton scattering technique

    SciTech Connect

    Tuschareon, S. Limkitjaroenporn, P. Kaewkhao, J.

    2014-03-24

    Topaz occurs in a wide range of colors, including yellow, orange, brown, pink-to-violet and blue. All of these color differences are due to color centers. In order to improve the color of natural colorless topaz, the most commonly used is irradiated with x- or gamma-rays, indicated that attenuation parameters is important to enhancements by irradiation. In this work, the mass attenuation coefficients of blue topaz were measured at the different energy of γ-rays using the Compton scattering technique. The results show that, the experimental values of mass attenuation coefficient are in good agreement with the theoretical values. The mass attenuation coefficients increase with the decrease in gamma rays energies. This may be attributed to the higher photon interaction probability of blue topaz at lower energy. This result is a first report of mass attenuation coefficient of blue topaz at different gamma rays energies.

  18. Effective atomic numbers of blue topaz at different gamma-rays energies obtained from Compton scattering technique

    NASA Astrophysics Data System (ADS)

    Tuschareon, S.; Limkitjaroenporn, P.; Kaewkhao, J.

    2014-03-01

    Topaz occurs in a wide range of colors, including yellow, orange, brown, pink-to-violet and blue. All of these color differences are due to color centers. In order to improve the color of natural colorless topaz, the most commonly used is irradiated with x- or gamma-rays, indicated that attenuation parameters is important to enhancements by irradiation. In this work, the mass attenuation coefficients of blue topaz were measured at the different energy of γ-rays using the Compton scattering technique. The results show that, the experimental values of mass attenuation coefficient are in good agreement with the theoretical values. The mass attenuation coefficients increase with the decrease in gamma rays energies. This may be attributed to the higher photon interaction probability of blue topaz at lower energy. This result is a first report of mass attenuation coefficient of blue topaz at different gamma rays energies.

  19. Antioxidant and antimicrobial activities of essential oils obtained from oregano (Origanum vulgare ssp. hirtum) by using different extraction methods.

    PubMed

    Karakaya, Sibel; El, Sedef Nehir; Karagözlü, Nural; Sahin, Serpil

    2011-06-01

    In this study, antioxidant and antimicrobial activities of essential oils obtained from oregano (Origanum vulgare ssp. hirtum) were determined by using solvent-free microwave extraction (SFME), supercritical fluid extraction, and conventional hydrodistillation (CH) methods. The inhibitory effects on the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical of essential oils obtained from oregano by using SFME and CH were similar. However, essential oil extracted by CH showed greater (2.69 μmol/μL of oil) Trolox equivalent antioxidant capacity (TEAC) than oregano oils obtained by SFME (P < .05). The difference between percentage inhibition and TEAC values most probably is due to the fact that undiluted and diluted samples are used in the percentage inhibition assay and the TEAC assay, respectively. TEAC values of oregano essential oils obtained by SFME at different microwave power levels were found to be similar and ranged from 0.72 to 0.84 μmol/μL of oil. Essential oils obtained by CH and SFME at different microwave powers inhibited the survival of Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli O157:H7, whereas survival of Staphylococcus aureus was not influenced. In addition, oregano oil obtained by SFME at 40% power level did not show any inhibitory effect on E. coli O157:H7.

  20. Mathematics. Iowa Developed Energy Activity Sampler, 6-12. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines. Div. of Instructional Services.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This document contains teaching activities which are intended to strengthen students' mathematics skills and concepts, while broadening their understanding of energy concepts. Each of the 24…

  1. [Comparative characteristic of activity of urease, incorporated into polysiloxane hydrogels and xerogels, obtained by sol-gel technique].

    PubMed

    Pohorilyĭ, R P; Honcharyk, V P; Kozhara, L I; Zub, Iu L; Chuĭko, O O

    2006-01-01

    Polysiloxane hydrogels with incorporated urease (degree of immobilization is 79-88%) that retains fermentative activity at the level of 56-84% were obtained by sol-gel technique. An influence of polysiloxane matrix functionalization on a degree of incorporation, activity retention and a factor of efficiency of urease immobilization was studied. Polysiloxane matrix functionalization with methyl groups causes decreasing a degree of ferment immobilization and a factor of immobilization efficiency. Functionalization of polysiloxane matrix with 3-aminopropyl groups leads to practically quantitative incorporation of the enzyme. And the highest degree of urease activity retention and maximal factor of its immobilization were observed at 3-aminopropyl groups content in polysiloxane matrix equals 2-5% (mol.). Transformation of hydrogels into xerogels via vacuum drying causes decreasing urease fermentative activity on nearly 2 orders.

  2. Αntioxidant activity of Cynara scolymus L. and Cynara cardunculus L. extracts obtained by different extraction techniques.

    PubMed

    Kollia, Eleni; Markaki, Panagiota; Zoumpoulakis, Panagiotis; Proestos, Charalampos

    2017-05-01

    Extracts of different parts (heads, bracts and stems) of Cynara cardunculus L. (cardoon) and Cynara scolymus L. (globe artichoke), obtained by two different extraction techniques (Ultrasound-Assisted Extraction (UAE) and classical extraction (CE)) were examined and compared for their total phenolic content (TPC) and their antioxidant activity. Moreover, infusions of the plant's parts were also analysed and compared to aforementioned samples. Results showed that cardoon's heads extract (obtained by Ultrasound-Assisted Extraction) displayed the highest TPC values (1.57 mg Gallic Acid Equivalents (GAE) g(-1) fresh weight (fw)), the highest DPPH(•) scavenging activity (IC50; 0.91 mg ml(-1)) and the highest ABTS(•+) radical scavenging capacity (2.08 mg Trolox Equivalents (TE) g(-1) fw) compared to infusions and other extracts studied. Moreover, Ultrasound-Assisted Extraction technique proved to be more appropriate and effective for the extraction of antiradical and phenolic compounds.

  3. The Limit of Free Magnetic Energy in Active Regions

    NASA Technical Reports Server (NTRS)

    Moore, Ron; Falconer, David; Sterling, Alphonse

    2012-01-01

    By measuring from active-region magnetograms a proxy of the free energy in the active region fs magnetic field, it has been found previously that (1) there is an abrupt upper limit to the free energy the field can hold that increases with the amount of magnetic field in the active region, the active region fs magnetic flux content, and (2) the free energy is usually near its limit when the field explodes in a CME/flare eruption. That is, explosive active regions are concentrated in a main-sequence path bordering the free-energy ]limit line in (flux content, free-energy proxy) phase space. Here, from measurement of Marshall Space Flight Center vector magnetograms, we find the magnetic condition that underlies the free ]energy limit and the accompanying main sequence of explosive active regions. Using a suitable free ]energy proxy measured from vector magnetograms of 44 active regions, we find that (1) in active regions at and near their free ]energy limit, the ratio of magnetic-shear free energy to the non ]free magnetic energy the potential field would have is approximately 1 in the core field, the field rooted along the neutral line, and (2) this ratio is progressively less in active regions progressively farther below their free ]energy limit. This shows that most active regions in which this core-field energy ratio is much less than 1 cannot be triggered to explode; as this ratio approaches 1, most active regions become capable of exploding; and when this ratio is 1 or greater, most active regions are compelled to explode. From these results we surmise the magnetic condition that determines the free ]energy limit is the ratio of the free magnetic energy to the non-free energy the active region fs field would have were it completely relaxed to its potential ]field configuration, and that this ratio is approximately 1 at the free-energy limit and in the main sequence of explosive active regions.

  4. FITPULS: a code for obtaining analytic fits to aggregate fission-product decay-energy spectra. [In FORTRAN

    SciTech Connect

    LaBauve, R.J.; George, D.C.; England, T.R.

    1980-03-01

    The operation and input to the FITPULS code, recently updated to utilize interactive graphics, are described. The code is designed to retrieve data from a library containing aggregate fine-group spectra (150 energy groups) from fission products, collapse the data to few groups (up to 25), and fit the resulting spectra along the cooling time axis with a linear combination of exponential functions. Also given in this report are useful results for aggregate gamma and beta spectra from the decay of fission products released from /sup 235/U irradiated with a pulse (10/sup -4/ s irradiation time) of thermal neutrons. These fits are given in 22 energy groups that are the first 22 groups of the LASL 25-group decay-energy group structure, and the data are expressed both as MeV per fission second and particles per fission second; these pulse functions are readily folded into finite fission histories. 65 figures, 11 tables.

  5. High antioxidant activity of coffee silverskin extracts obtained by the treatment of coffee silverskin with subcritical water.

    PubMed

    Narita, Yusaku; Inouye, Kuniyo

    2012-12-01

    Coffee silverskin (CS) is a thin tegument of the outer layer of green coffee beans and a major by-product of the roasting process to produce roasted coffee beans. CS extracts obtained by the treatment of CS with subcritical water at 25-270°C were investigated for their antioxidant activity using hydrophilic oxygen radical absorption capacity (H-ORAC) and DPPH radical scavenging capacity assays. The antioxidant activity increased with increasing the extraction temperature and the highest activity was observed with the extracts obtained at 270°C. The H-ORAC and DPPH values of the extracts were 2629±193 and 379±36μmol TE/g of CS extract, respectively. High correlation (R=0.999) was observed between H-ORAC and DPPH values for the CS extracts. High correlation of the antioxidant activity was also observed with protein and phenolic contents in the extracts. The CS extracts could be useful as a good source of antioxidative materials.

  6. Structural studies of calcium phosphate doped with titanium and zirconium obtained by high-energy mechanical alloying

    NASA Astrophysics Data System (ADS)

    Silva, C. C.; Sombra, A. S. B.

    2009-12-01

    In this paper, we present a new variation of the solid-state procedure on the synthesis of bioceramics with titanium (CapTi) and zirconium (CapZr), considering that zirconium (ZrO2) and titanium oxide (TiO2) are strengthening agents, due to their superb force and fracture toughness. The high efficiency of the calcination process opens a new way of producing commercial amounts of nanocrystalline bioceramics. In this work, a new variation of the solid-state procedure method was used to produce nanocrystalline powders of titanium and zirconium, using two different experimental chemical routes: CapTi: Ca(H2PO4)2+TiO2 and CapZr: Ca(H2PO4)2+ZrO2. The powders were submitted to calcination processes (CapTic and CapZrc) at 800, 900 and 1000 °C. The calcium titanium phosphate phase, CaTi4P6O24, was obtained in the CapTic reaction and the calcium zirconium phosphate, CaZr4P6O24, was obtained in the CapZrc reaction. The obtained ceramics were characterized by x-ray powder diffraction (XRD), infrared (IR) spectroscopy, Raman scattering spectroscopy (RSS) and scanning electron microscopy (SEM) analysis. This method was compared with the milling process (CapTim and CapZrm), where in the last process the melting is not necessary and the powder obtained is nanocrystalline. The calcium titanium phosphate phase, CaTi4P6O24, was obtained in the reaction CapTim, but in CapZrm the formation of any calcium phosphate phase even after 15 h of dry mechanical alloying was not observed.

  7. Simple Activity Demonstrates Wind Energy Principles

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    Wind energy is an exciting and clean energy option often described as the fastest-growing energy system on the planet. With some simple materials, teachers can easily demonstrate its key principles in their classroom. (Contains 1 figure and 2 tables.)

  8. Pyrolysis of activated sludge: energy analysis and its technical feasibility.

    PubMed

    Agarwal, Manu; Tardio, James; Venkata Mohan, S

    2015-02-01

    A comprehensive study on the potential of pyrolysis of activated sludge to generate substances that can be used to produce energy was evaluated for its technical and environmental viability. The products of the process viz., pyrolysis gas, pyrolysis oil and char can readily be used by the major energy consumers viz., electricity and transportation. Based on the results obtained it is estimated that a 1 ton capacity process for pyrolysis of activated sludge can serve the electrical needs of a maximum of 239, 95 and 47 Indian houses per day, considering lower middle class, middle class and upper middle class, respectively. In addition the process would also produce the daily methane (CNG) requirement of 128 public transport buses. The process was determined to be technically feasible at low and medium temperatures for both, pyrolysis gas and electrical energy. The gas generated could be utilized as fuel directly while the oil generated would require pretreatment before its potential application. The process is potentially sustainable when commercialized and can self-sustain in continuous mode of operation in biorefinery context.

  9. Vasorelaxant activity of extracts obtained from Apium graveolens: Possible source for vasorelaxant molecules isolation with potential antihypertensive effect

    PubMed Central

    Jorge, Vergara-Galicia; Ángel, Jimenez-Ramirez Luis; Adrián, Tun-Suarez; Francisco, Aguirre-Crespo; Anuar, Salazar-Gómez; Samuel, Estrada-Soto; Ángel, Sierra-Ovando; Emmanuel, Hernandez-Nuñez

    2013-01-01

    Objective To investigate vasorelaxant effect of organic extracts from Apium graveolens (A. graveolens) which is a part of a group of plants subjected to pharmacological and phytochemical study with the purpose of offering it as an ideal source for obtaining lead compounds for designing new therapeutic agents with potential vasorelaxant and antihypertensive effects. Methods An ex vivo method was employed to assess the vasorelaxant activity. This consisted of using rat aortic rings with and without endothelium precontracted with norepinephrine. Results All extracts caused concentration-dependent relaxation in precontracted aortic rings with and without endothelium; the most active extracts were Dichloromethane and Ethyl Acetate extracts from A. graveolens. These results suggested that secondary metabolites responsible for the vasorelaxant activity belong to a group of compounds of medium polarity. Also, our evidence showed that effect induced by dichloromethane and ethyl acetate extracts from A. graveolens is mediated probably by calcium antagonism. Conclusions A. graveolens represents an ideal source for obtaining lead compounds for designing new therapeutic agents with potential vasorelaxant and antihypertensive effects. PMID:24075341

  10. Comparison of antimicrobial activities of newly obtained low molecular weight scorpion chitosan and medium molecular weight commercial chitosan.

    PubMed

    Kaya, Murat; Asan-Ozusaglam, Meltem; Erdogan, Sevil

    2016-06-01

    In this study the antimicrobial activity of low molecular weight (3.22 kDa) chitosan, obtained for the first time from a species belonging to the Scorpiones, was screened against nine pathogenic microorganisms (seven bacteria and two yeasts) and compared with that of medium molecular weight commercial chitosan (MMWCC). It was observed that the antimicrobial activity of the low molecular weight scorpion chitosan (LMWSC) was specific to bacterial species in general rather than gram-negative or gram-positive bacterial groups. It was also determined that LMWSC had a stronger inhibitory effect than the MMWCC, particularly on the bacterium Listeria monocytogenes and the yeast Candida albicans, which are important pathogens for public health. In addition, it was recorded that the MMWCC had a greater inhibitory effect on Bacillus subtilis than LMWSC. According to the results obtained by the disc diffusion method, the antibacterial activity of both LMWSC and MMWCC against B. subtilis and Salmonella enteritidis was higher than the widely used antibiotic Gentamicin (CN, 10 μg/disc).

  11. CuO/ZnO coupled oxide films obtained by the electrodeposition technique and their photocatalytic activity in phenol degradation under solar irradiation.

    PubMed

    Paz, Diego S; Foletto, Edson L; Bertuol, Daniel A; Jahn, Sérgio L; Collazzo, Gabriela C; da Silva, Syllos S; Chiavone-Filho, Osvaldo; do Nascimento, Claudio A O

    2013-01-01

    CuO/ZnO coupled oxide films were electrodeposited onto an aluminum substrate and tested as photocatalysts in degradation of phenol molecules in aqueous solution under sunlight. The obtained films were characterized by X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results showed that the photocatalytic activity of films was significant, especially to coupled oxide film with a CuO/ZnO ratio equal to 0.697, which presented about 70% degradation of the aromatic molecules and 42% of total organic carbon (TOC) removal at 300 min under solar irradiation. Therefore, this work highlights the potential application of CuO/ZnO coupled oxide films obtained by electrodeposition onto aluminum substrate in the field of photocatalysis.

  12. Sample Energy Conservation Education Activities for Elementary School Students.

    ERIC Educational Resources Information Center

    Allen, Rodney F., Ed.; LaHart, David E., Ed.

    The booklet contains learning activities for introducing energy and conservation concepts into the existing elementary school curriculum. The activities were developed by Palm Beach County teachers during a one-week workshop. A framework of ideas is divided into three functional categories: universe of energy, living systems and energy, and social…

  13. Selection of suitable detergents for obtaining an active dengue protease in its natural form from E. coli.

    PubMed

    Liew, Lynette Sin Yee; Lee, Michelle Yueqi; Wong, Ying Lei; Cheng, Jinting; Li, Qingxin; Kang, CongBao

    2016-05-01

    Dengue protease is a two-component enzyme and is an important drug target against dengue virus. The protease activity and protein stability of dengue nonstructural protein 3 (NS3) require a co-factor region from a four-span membrane protein NS2B. A natural form of dengue protease containing full-length NS2B and NS3 protease domain NS2BFL-NS3pro will be useful for dengue drug discovery. In current study, detergents that can be used for protease purification were tested. Using a water soluble protease construct, 39 detergents were selected for both NS2B and NS2BFL-NS3pro purification. The results showed that 18 detergents were able to sustain the activity of the natural dengue protease and 11 detergents could be used for NS2B purification. The results obtained in this study will be useful for biochemical and biophysical studies on dengue protease.

  14. Anti-Mycobacterium tuberculosis Activity of Calophyllum brasiliense Extracts Obtained by Supercritical Fluid Extraction and Conventional Techniques.

    PubMed

    Pires, Claudia T A; de L Scodro, Regiane B; Brenzan, Mislaine A; Cortez, Diógenes A G; Siqueira, Vera L D; Cardozo-Filho, Lúcio; Goncalves, Renata M; Caleffi-Ferracioli, Katiany R; Cardoso, Rosilene F

    2016-01-01

    The conventional techniques used to extract natural products have many disadvantages, and alternative methods have been used, such as supercritical fluid extraction (SFE-CO2). We compared the anti-Mycobacterium tuberculosis activity and cytotoxicity of extracts and major pure compounds were obtained from the leaves of Calophyllum brasiliense by SFE-CO2, maceration and Soxhlet. Anti-M tuberculosis activity was evaluated by resazurin microtiter assay plate and cytotoxicity assay was performed using 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide. The (-) mammea A/BB, (-) mammea B/BB, mammea B/BB cyclo D, ponnalide, mammea A/BA cyclo D, and amentoflavone were identified as the majority compounds. SFE-CO2, especially at 313 K and 10.92 MPa showed better yield for (-) mammea A/BB. Anti-M. tuberculosis activity (62.5 μg/mL) and cytotoxicity (Selectivity Index = 0.320-0.576) were similar for the three extracts. Mammea B/BB cyclo D had a minimum inhibitory concentration (MIC) of 125 μg/mL, and ponnalide and mammea A/BA cyclo D had MICs > 250 μg/mL. The pure compounds isolated showed low Selectivity Index (< 0.09). SFE-CO2 may be more promising than conventional methods for the extraction of compound (-) mammea A/BB, which presented the best anti-M. tuberculosis activity in our previous study. This is important for current industrial requirements to obtain extracts from medicinal plants using clean technologies.

  15. Promoting Active Transport in Older Adolescents Before They Obtain Their Driving Licence: A Matched Control Intervention Study

    PubMed Central

    Simons, Dorien; Van Cauwenberg, Jelle; Van Dyck, Delfien; Vandelanotte, Corneel; de Geus, Bas; De Bourdeaudhuij, Ilse; Clarys, Peter; Deforche, Benedicte

    2016-01-01

    Background Active transport has great potential to increase physical activity in older adolescents (17–18 years). Therefore, a theory- and evidence-based intervention was developed aiming to promote active transport among older adolescents. The intervention aimed to influence psychosocial factors of active transport since this is the first step in order to achieve a change in behaviour. The present study aimed to examine the effect of the intervention on the following psychosocial factors: intention to use active transport after obtaining a driving licence, perceived benefits, perceived barriers, subjective norm, self-efficacy, habit and awareness towards active transport. Methods A matched control three-arm study was conducted and consisted of a pre-test post-test design with intervention and control schools in Flanders (northern part of Belgium). A lesson promoting active transport was implemented as the last lesson in the course ‘Driving Licence at School’ in intervention schools (intervention group 1). Individuals in intervention group 2 received this active transport lesson and, in addition, they were asked to become a member of a Facebook group on active transport. Individuals in the control group only attended the regular course ‘Driving Licence at School’. Participants completed a questionnaire assessing socio-demographics and psychosocial variables at baseline, post (after one week) and follow-up (after eight weeks). To assess intervention effects, multilevel linear mixed models analyses were performed. Results A sample of 441 older adolescents (56.8% female; 17.4 (0.7) years) was analysed. For awareness regarding the existence of car sharing schemes, a significant increase in awareness from baseline to post measurement was found within intervention group 1 (p = 0.001) and intervention group 2 (p = 0.030) compared to the control group in which no change was found. In addition, a significant increase in awareness from baseline to follow

  16. Motivation to obtain a food reward of pregnant ewes in negative energy balance: behavioural, metabolic and endocrine considerations.

    PubMed

    Verbeek, E; Waas, J R; Oliver, M H; McLeay, L M; Ferguson, D M; Matthews, L R

    2012-07-01

    Low food availability often coincides with pregnancy in grazing animals. This study investigated how chronic reductions in food intake affected feeding motivation, and metabolic and endocrine parameters in pregnant sheep, which might be indicative of compromised welfare. Ewes with an initial Body Condition Score of 2.7±0.3 (BCS; 0 indicates emaciation and 5 obesity) were fed to attain low (LBC 2.0±0.0,), medium (MBC 2.9±0.1) or high BCS (HBC 3.7±0.1) in the first trimester of pregnancy. A feeding motivation test in which sheep were required to walk a set distance for a palatable food reward was conducted in the second trimester. LBC and MBC ewes consumed more rewards (P=0.001) and displayed a higher expenditure (P=0.02) than HBC ewes, LBC ewes also tended to consume more rewards than MBC ewes (P=0.09). Plasma leptin and glucose concentrations were inversely correlated to expenditure (both P<0.05) and appear to be associated with hunger in sheep. LBC ewes were in negative energy balance, with lower muscle dimensions, plasma glucose, leptin, insulin, cortisol, and insulin-like growth factor-1 concentrations and higher free fatty acids concentrations compared to HBC ewes; metabolic and endocrine parameters of the MBC ewes were intermediate. The high feeding motivation and negative energy balance of low BCS ewes suggested an increased risk of compromised welfare. Imposing even a small cost on a food reward reduced motivation substantially in high BCS ewes (despite high intake when food was freely available). Assessment of a willingness to work for rewards, combined with measures of key metabolic and endocrine parameters, may provide sensitive barometers of welfare in energetically-taxed animals.

  17. Ligand reorganization and activation energies in nonadiabatic electron transfer reactions

    NASA Astrophysics Data System (ADS)

    Zhu, Jianjun; Wang, Jianji; Stell, George

    2006-10-01

    The activation energy and ligand reorganization energy for nonadiabatic electron transfer reactions in chemical and biological systems are investigated in this paper. The free energy surfaces and the activation energy are derived exactly in the general case in which the ligand vibration frequencies are not equal. The activation energy is derived by free energy minimization at the transition state. Our formulation leads to the Marcus-Hush [J. Chem. Phys. 24, 979 (1956); 98, 7170 (1994); 28, 962 (1958)] results in the equal-frequency limit and also generalizes the Marcus-Sumi [J. Chem. Phys. 84, 4894 (1986)] model in the context of studying the solvent dynamic effect on electron transfer reactions. It is found that when the ligand vibration frequencies are different, the activation energy derived from the Marcus-Hush formula deviates by 5%-10% from the exact value. If the reduced reorganization energy approximation is introduced in the Marcus-Hush formula, the result is almost exact.

  18. Biophysical characterization and activity analysis of nano-magnesium supplemented cellulase obtained from a psychrobacterium following graphene oxide immobilization.

    PubMed

    Dutta, N; Biswas, S; Saha, M K

    2016-12-01

    Cellulase enzyme was purified from a psychrophilic strain of Bacillus subtilis obtained from east Himalayan mountains. The native enzyme showed optimum activity at 15°C and pH 8.0.The Magnesium oxide nanoparticle (MgN) supplemented enzyme when immobilized on graphene oxide nanosupport (GO), via glutaraldehyde as cross linker, showed 2.98 folds increase in enzymatic activity at 8°C and more than 3.5 folds activity increment at 90°C. The MgN-cel on graphene (GO-MgN-cel) showed a decrease in Km by 6.7 folds at 8°C and 34 folds at 90°C. GO-MgN-cel showed 5 fold and 4.7 fold increase in Vmax at 8°C and 90°C respectively than the untreated enzyme.When compared to native enzyme, GO-MgN-cel had t1/2 (half life) and Ed increased by 72.5 fold and 2.48 fold respectively at 90°C; and 41.6 fold and 2.19 fold respectively at 8°C. Enzymatic activity of GO-MgN-cel was retained even after 12 repeated uses and showed storage stability at 4°C for more than 120days. This nanoparticle assisted immobilization technique can be utilized in bioprocessing industries which require functioning at these extreme ranges of temperature.

  19. Energy Conservation Activity Packet, Grade 5. Revised Edition.

    ERIC Educational Resources Information Center

    Pohlman, Betty; And Others

    This activity notebook for grade 5 is one of a series developed in response to energy conservation. It contains activities that stress an energy conservation ethic and includes many values clarification activities for grade five. The packet is divided into two parts and provides the teacher with background information, concepts and objectives, and…

  20. Energy Conservation Activities for the Classroom K-12.

    ERIC Educational Resources Information Center

    Kentucky Dept. of Energy, Frankfort.

    After a brief introduction entitled "Where Does the Energy We Use Come From," this unit presents 86 activities. Each activity gives the title, concept, objectives, subject area, level, time involved, materials needed, procedures, and related career activities. Topics cover everything from housing insulation to alternate sources of energy to energy…

  1. Energy Conservation Activity Packet, Grade 6. Revised Edition.

    ERIC Educational Resources Information Center

    Pohlman, Betty; And Others

    This activity notebook for grade 6 is one of a series developed in response to the concern for energy conservation. It contains activities that stress an energy conservation ethic and includes many values clarification activities for grade six. The packet is divided into two parts and provides the teacher with background information, concepts and…

  2. Energy Conservation Activity Packet, Grade 4. Revised Edition.

    ERIC Educational Resources Information Center

    Pohlman, Betty; And Others

    This activity notebook for grade 4 is one in a series developed in response to the concern for energy conservation. It contains activities that stress an energy conservation ethic and includes many values clarification activities for grade four. The packet is divided into two parts and provides the teacher with background information, concepts and…

  3. Structure and Antioxidant Activity of Soy Protein Isolate-Dextran Conjugates Obtained by TiO2 Photocatalysis

    PubMed Central

    Jin, Bei; Zhou, Xiaosong; Li, Bing; Chen, Caiyan; Zhang, Xiaosa; Chen, Siqiao

    2015-01-01

    The aim of this study was to investigate the structural characteristics and antioxidant activities of soy protein isolate- (SPI-) dextran conjugates obtained by TiO2 photocatalysis treatment. Results revealed that the UV-vis absorption and the fluorescence intensity increased as the photocatalytic power increased (P < 0.05). Higher photocatalytic power could promote the extent of glycation and the formation of high molecular weight SPI-dextran conjugates, which were evidenced by free amino group content and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The Fourier transform infrared (FT-IR) spectra suggested that the amide I, II, and III bands of SPI were altered by the glycation induced by TiO2 photocatalysis. Moreover, significant changes of secondary structure occurred in SPI-dextran conjugates. The α-helix, β-sheet, β-turns, and random coil were changed from approximately 10.6%, 37.9%, 12.9%, and 38.6% to 3.8%, 10.4%, 17.7%, and 68.8%, respectively, after treatment at photocatalytic power of 1000 W. In addition, SPI-dextran conjugates obtained by TiO2 photocatalysis treatment exhibited high hydroxyl radical scavenging activity and possessed increased reducing power. All data indicated that TiO2 photocatalysis was an efficient method for promoting protein-polysaccharide copolymerisation. PMID:26495283

  4. Extraction optimization for obtaining Artemisia capillaris extract with high anti-inflammatory activity in RAW 264.7 macrophage cells.

    PubMed

    Jang, Mi; Jeong, Seung-Weon; Kim, Bum-Keun; Kim, Jong-Chan

    2015-01-01

    Plant extracts have been used as herbal medicines to treat a wide variety of human diseases. We used response surface methodology (RSM) to optimize the Artemisia capillaris Thunb. extraction parameters (extraction temperature, extraction time, and ethanol concentration) for obtaining an extract with high anti-inflammatory activity at the cellular level. The optimum ranges for the extraction parameters were predicted by superimposing 4-dimensional response surface plots of the lipopolysaccharide- (LPS-) induced PGE2 and NO production and by cytotoxicity of A. capillaris Thunb. extracts. The ranges of extraction conditions used for determining the optimal conditions were extraction temperatures of 57-65°C, ethanol concentrations of 45-57%, and extraction times of 5.5-6.8 h. On the basis of the results, a model with a central composite design was considered to be accurate and reliable for predicting the anti-inflammation activity of extracts at the cellular level. These approaches can provide a logical starting point for developing novel anti-inflammatory substances from natural products and will be helpful for the full utilization of A. capillaris Thunb. The crude extract obtained can be used in some A. capillaris Thunb.-related health care products.

  5. Structure and antioxidant activity of soy protein isolate-dextran conjugates obtained by TiO2 photocatalysis.

    PubMed

    Jin, Bei; Zhou, Xiaosong; Li, Bing; Chen, Caiyan; Zhang, Xiaosa; Chen, Siqiao

    2015-01-01

    The aim of this study was to investigate the structural characteristics and antioxidant activities of soy protein isolate- (SPI-) dextran conjugates obtained by TiO2 photocatalysis treatment. Results revealed that the UV-vis absorption and the fluorescence intensity increased as the photocatalytic power increased (P < 0.05). Higher photocatalytic power could promote the extent of glycation and the formation of high molecular weight SPI-dextran conjugates, which were evidenced by free amino group content and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The Fourier transform infrared (FT-IR) spectra suggested that the amide I, II, and III bands of SPI were altered by the glycation induced by TiO2 photocatalysis. Moreover, significant changes of secondary structure occurred in SPI-dextran conjugates. The α-helix, β-sheet, β-turns, and random coil were changed from approximately 10.6%, 37.9%, 12.9%, and 38.6% to 3.8%, 10.4%, 17.7%, and 68.8%, respectively, after treatment at photocatalytic power of 1000 W. In addition, SPI-dextran conjugates obtained by TiO2 photocatalysis treatment exhibited high hydroxyl radical scavenging activity and possessed increased reducing power. All data indicated that TiO2 photocatalysis was an efficient method for promoting protein-polysaccharide copolymerisation.

  6. Antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution

    PubMed Central

    Perito, Brunella; Giorgetti, Emilia; Marsili, Paolo

    2016-01-01

    Summary Silver nanoparticles (AgNPs) have increasingly gained importance as antibacterial agents with applications in several fields due to their strong, broad-range antimicrobial properties. AgNP synthesis by pulsed laser ablation in liquid (PLAL) permits the preparation of stable Ag colloids in pure solvents without capping or stabilizing agents, producing AgNPs more suitable for biomedical applications than those prepared with common, wet chemical preparation techniques. To date, only a few investigations into the antimicrobial effect of AgNPs produced by PLAL have been performed. These have mainly been performed by ablation in water with nanosecond pulse widths. We previously observed a strong surface-enhanced Raman scattering (SERS) signal from such AgNPs by “activating” the NP surface by the addition of a small quantity of LiCl to the colloid. Such surface effects could also influence the antimicrobial activity of the NPs. Their activity, on the other hand, could also be affected by other parameters linked to the ablation conditions, such as the pulse width. The antibacterial activity of AgNPs was evaluated for NPs obtained either by nanosecond (ns) or picosecond (ps) PLAL using a 1064 nm ablation wavelength, in pure water or in LiCl aqueous solution, with Escherichia coli and Bacillus subtilis as references for Gram-negative and Gram-positive bacteria, respectively. In all cases, AgNPs with an average diameter less than 10 nm were obtained, which has been shown in previous works to be the most effective size for bactericidal activity. The measured zeta-potential values were very negative, indicating excellent long-term colloidal stability. Antibacterial activity was observed against both microorganisms for the four AgNP formulations, but the ps-ablated nanoparticles were shown to more effectively inhibit the growth of both microorganisms. Moreover, LiCl modified AgNPs were the most effective, showing minimum inhibitory concentration (MIC) values in a

  7. Determination of lead(II) sorption capacity of hazelnut shell and activated carbon obtained from hazelnut shell activated with ZnCl2.

    PubMed

    Şencan, Aziz; Karaboyacı, Mustafa; Kılıç, Mehmet

    2015-03-01

    This study aimed to determine the Pb(+2) adsorption capacities of hazelnut shell and activated carbon obtained from hazelnut shell. It also aimed to determine the effect of ZnCl2 in the activation process. The hazelnut was pyrolyzed at 250 and 700 °C. For determining the capture speed of the adsorbents, the pseudo-first- and second-order kinetic studies were performed. The Freundlich and Langmuir isotherm models were used to determine adsorption equilibrium. The surface characterization of hazelnut shell and activated carbon was determined by Brunauer-Emmett-Teller (BET) analysis and FTIR spectrum. Pb(+2) adsorption capacity of obtaining activated carbon was determined by ICP-OES analysis. The raw hazelnut shell's BET surface area is 5.92 m(2)/g and the surface area of activated carbons which is pyrolyzed at 250 and 700 °C were determined (270.2 and 686.7 m(2)/g, respectively. The surface area of hazelnut shell, which pyrolyzed at 700 °C after being activated with ZnCl2, was determined to be 736.49 m(2)/g. Results show that physical adsorption process is dominant for the activated carbon pyrolysis at 700 °C but the chemical adsorption is dominant for the activated carbon pyrolysis at lower degrees and for raw hazelnut shell.

  8. Comparative Composition and Antioxidant Activity of Peptide Fractions Obtained by Ultrafiltration of Egg Yolk Protein Enzymatic Hydrolysates

    PubMed Central

    Chay Pak Ting, Bertrand P.; Mine, Yoshinori; Juneja, Lekh R.; Okubo, Tsutomu; Gauthier, Sylvie F.; Pouliot, Yves

    2011-01-01

    The objective of the study was to compare the antioxidant activity of two distinct hydrolysates and their peptide fractions prepared by ultrafiltration (UF) using membranes with molecular weight cut-off of 5 and 1 kDa. The hydrolysates were a delipidated egg yolk protein concentrate (EYP) intensively hydrolyzed with a combination of two bacterial proteases, and a phosphoproteins (PPP) extract partially hydrolyzed with trypsin. Antioxidant activity, as determined by the oxygen radical absorbance capacity (ORAC) assay, was low for EYP and PPP hydrolysates with values of 613.1 and 489.2 μM TE·g−1 protein, respectively. UF-fractionation of EYP hydrolysate increased slightly the antioxidant activity in permeate fractions (720.5–867.8 μM TE·g−1 protein). However, ORAC values were increased by more than 3-fold in UF-fractions prepared from PPP hydrolysate, which were enriched in peptides with molecular weight lower than 5 kDa. These UF-fractions were characterized by their lower N/P atomic ratio and higher phosphorus content compared to the same UF-fractions obtained from EYP-TH. They also contained high amounts of His, Met, Leu, and Phe, which are recognized as antioxidant amino acids, but also high content in Lys and Arg which both represent target amino acids of trypsin used for the hydrolysis of PPP. PMID:24957729

  9. Antifungal, Phytotoxic, and Cytotoxic Activities of Metabolites from Epichloë bromicola, a Fungus Obtained from Elymus tangutorum Grass.

    PubMed

    Song, Qiu-Yan; Nan, Zhi-Biao; Gao, Kun; Song, Hui; Tian, Pei; Zhang, Xing-Xu; Li, Chun-Jie; Xu, Wen-Bo; Li, Xiu-Zhang

    2015-10-14

    The development of high-quality herbage is an important aspect of animal husbandry. Inoculating beneficial fungi onto inferior grass is a feasible strategy for producing new varieties of high-quality herbage. Epichloë bromicola is a candidate fungus that is isolated from Elymus tangutorum. A total of 17 metabolites, 1-17, were obtained from E. bromicola, and their biological activities were assayed. Metabolite 1 exhibited antifungal activities against Alternaria alternata, Fusarium avenaceum, Bipolaris sorokiniana, and Curvularia lunata. EC50 values ranged from 0.7 to 5.3 μM, which were better than the positive control, chlorothalonil. Metabolite 8 displayed obvious phytotoxic effects toward Lolium perenne and Poa crymophila seedlings, and it was as active as glyphosate. None of these isolated metabolites displayed cytotoxicity against Madin-Darby bovine kidney cells. The IC50 values were greater than 100 μM, and the metabolites increased the growth of the cells at a concentration of 12.5 μM. The bioassay indicated that E. bromicola may be a beneficial fungus for producing new varieties of herbage with various resistances. Additionally, metabolite 7, 3-(2'-(4″-hydroxyphenyl)acetoxy)-2S-methylpropanoic acid, is a new natural product, and its stereochemistry was determined by means of optical rotation computation and chemical reactions.

  10. Biological activities of peptide concentrates obtained from hydrolysed eggshell membrane byproduct by optimisation with response surface methodology.

    PubMed

    Santana, Ana; Melo, Armindo; Tavares, Tânia; Ferreira, Isabel M P L V O

    2016-11-09

    The increase of hen egg consumption demands profitable applications for eggshells, including their membranes, in order to minimize environmental and public health problems that could result from their accumulation. This work presents an innovative application for eggshell membranes to obtain an added-value food ingredient that combines maximized ACE-inhibitory and antioxidant activities. Firstly, the use of acetic acid 5% (v/v); and 3-mercaptopropionic acid 1.25 M enabled 63% recovery of eggshell membrane proteins. Secondly, the extracted proteins were hydrolysed by alcalase from Bacillus licheniformis, viscozyme L and protease from Bacillus amyloliquefaciens. Hydrolysis conditions were optimized using response surface methodology experimental design. The ACE-inhibitory activity (IC50) was 34.5 ± 2.1 μg mL(-1), 63.0 ± 4.2 μg mL(-1) and 43.0 ± 8.5 μg mL(-1) for each enzyme, respectively, and the antioxidant activity was ca. 4.0 μmoltrolox equivalent mg(-1)hydrolysed protein. The combination of both bioactive properties is of potential interest to control cardiovascular diseases.

  11. Estimating oxygen uptake and energy expenditure during treadmill walking by neural network analysis of easy-to-obtain inputs.

    PubMed

    Beltrame, Thomas; Amelard, Robert; Villar, Rodrigo; Shafiee, Mohammad J; Wong, Alexander; Hughson, Richard L

    2016-11-01

    The study of oxygen uptake (V̇o2) dynamics during walking exercise transitions adds valuable information regarding fitness. However, direct V̇o2 measurements are not practical for general population under realistic settings. Devices to measure V̇o2 are associated with elevated cost, uncomfortable use of a mask, need of trained technicians, and impossibility of long-term data collection. The objective of this study was to predict the V̇o2 dynamics from heart rate and inputs from the treadmill ergometer by a novel artificial neural network approach. To accomplish this, 10 healthy young participants performed one incremental and three moderate constant work rate treadmill walking exercises. The speed and grade used for the moderate-intensity protocol was related to 80% of the V̇o2 response at the gas exchange threshold estimated during the incremental exercise. The measured V̇o2 was used to train an artificial neural network to create an algorithm able to predict the V̇o2 based on easy-to-obtain inputs. The dynamics of the V̇o2 response during exercise transition were evaluated by exponential modeling. Within each participant, the predicted V̇o2 was strongly correlated to the measured V̇o2 ( = 0.97 ± 0.0) and presented a low bias (~0.2%), enabling the characterization of the V̇o2 dynamics during treadmill walking exercise. The proposed algorithm could be incorporated into smart devices and fitness equipment, making them suitable for tracking changes in aerobic fitness and physical health beyond the infrequent monitoring of patients during clinical interventions and rehabilitation programs.

  12. Energy cost and energy sources during a simulated firefighting activity.

    PubMed

    Perroni, Fabrizio; Tessitore, Antonio; Cortis, Cristina; Lupo, Corrado; D'artibale, Emanuele; Cignitti, Lamberto; Capranica, Laura

    2010-12-01

    This study aimed to 1) analyze the energy requirement (VO2eq) and the contribution of the aerobic (VO2ex), anaerobic alactic (VO2al), and anaerobic lactic (VO2la-) energy sources of a simulated intervention; 2) ascertain differences in mean VO2 and heart rate (HR) during firefighting tasks; and 3) verify the relationship between time of job completion and the fitness level of firefighters. Twenty Italian firefighters (age = 32 ± 6 yr, VO2peak = 43.1 ± 4.9 mL·kg·min) performed 4 consecutive tasks (i.e., child rescue; 250-m run; find an exit; 250-m run) that required a VO2eq of 406.26 ± 73.91 mL·kg (VO2ex = 86 ± 5%; VO2al = 9 ± 3%; VO2la- = 5 ± 3%). After 30 minutes, the recovery HR (108 ± 15 beats·min) and VO2 (8.86±2.67mL·kg·min) were higher (p < 0.0001) than basal values (HR = 66 ± 8 beats·min; VO2 = 4.57 ± 1.07 mL·kg·min), indicating that passive recovery is insufficient in reducing the cardiovascular and thermoregulatory strain of the previous workload. Differences (p < 0.001) between tasks emerged for mean VO2 and HR, with a lack of significant correlation between the time of job completion and the firefighters' aerobic fitness. These findings indicate that unpredictable working conditions highly challenge expert firefighters who need adequate fitness levels to meet the requirements of their work. Practically, to enhance the fitness level of firefighters, specific interval training programs should include a wide variety of tasks requiring different intensities and decision-making strategies.

  13. Energy Conservation Activities for Elementary Grades (Or: How to Help Slim Down the Energy Monster). Iowa Developed Energy Activities Sampler, Intermediate 3-5.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines. Div. of Instructional Services.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This booklet provides activities for teachers in the intermediate elementary grades (3-5) and is designed to enable students to develop a comprehensive understanding of energy concepts. Each…

  14. Energy Conservation Activities for Elementary Grades (Or: How To Help Slim Down the Energy Monster). Iowa Developed Energy Activities Sampler, Intermediate 3-5. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This booklet provides activities for teachers in the intermediate elementary grades (3-5) and is designed to enable students to develop a comprehensive understanding of energy concepts. Each…

  15. A reduced energy supply strategy in active vibration control

    NASA Astrophysics Data System (ADS)

    Ichchou, M. N.; Loukil, T.; Bareille, O.; Chamberland, G.; Qiu, J.

    2011-12-01

    In this paper, a control strategy is presented and numerically tested. This strategy aims to achieve the potential performance of fully active systems with a reduced energy supply. These energy needs are expected to be comparable to the power demands of semi-active systems, while system performance is intended to be comparable to that of a fully active configuration. The underlying strategy is called 'global semi-active control'. This control approach results from an energy investigation based on management of the optimal control process. Energy management encompasses storage and convenient restitution. The proposed strategy monitors a given active law without any external energy supply by considering purely dissipative and energy-demanding phases. Such a control law is offered here along with an analysis of its properties. A suboptimal form, well adapted for practical implementation steps, is also given. Moreover, a number of numerical experiments are proposed in order to validate test findings.

  16. Activation energies of metal atomization and nitrate and sulfate decomposition in concentrated matrices (10 -1 M).

    NASA Astrophysics Data System (ADS)

    Le Bihan, A.; Le Garrec, H.; Cabon, J. Y.; Guern, Y.

    1998-08-01

    This paper reports on activation energies measured during copper and manganese atomization in a graphite furnace in the presence of large amounts of nitrate and sulfate matrices. It also deals with activation energies corresponding to the decomposition of these matrices and to the atomization of their metal, i.e. Na, Ca or Mg. These results were obtained from Arrhenius-type calculations carried out on specific and non-specific absorbance values. Atomization was achieved under a very high gas flow which allowed us to get to the source function. Some of the calculated energies were compared to reaction energies deduced from tables of thermodynamic data.

  17. High-energy gamma-ray observations of active galaxies

    NASA Technical Reports Server (NTRS)

    Fichtel, Carl E.

    1994-01-01

    During the period from 1992 May to early 1992 November, the Energetic Gamma-Ray Experiment Telescope (EGRET) on board the Compton Gamma Ray Observatory obtained high-energy gamma-ray data for most of the sky. A total of 18 active galaxies have been seen with high certainty, and it is expected that more will be found in the data when a more thorough analysis is complete. All of those that have been seen are radio-loud quasars or BL Lacertae objects; most have already been identified as blazars. No Seyfert galaxies have been found thus far. If the spectra are represented as a power law in energy, spectral slopes ranging from approximately -1.7 to -2.4 are found. A wide range of z-values exits in the observed sample, eight having values in excess of 1.0. Time variations have been seen, with the timescale for a significant change being as short as days in at least one case. These results imply the existence of very large numbers of relativistic particles, probably close to the central object. Although a large extrapolation is required, their existence also suggests that these active galactic nuclei may be the source of the extragalactic cosmic rays.

  18. High yields of active Thermus thermophilus proline dehydrogenase are obtained using maltose-binding protein as a solubility tag.

    PubMed

    Huijbers, Mieke M E; van Berkel, Willem J H

    2015-03-01

    Proline dehydrogenase (ProDH) catalyzes the FAD-dependent oxidation of proline to Δ(1) -pyrroline-5-carboxylate, the first step of proline catabolism in many organisms. Next to being involved in a number of physiological processes, ProDH is of interest for practical applications because the proline imino acid can serve as a building block for a wide range of peptides and antibiotics. ProDH is a membrane-associated protein and recombinant soluble forms of the enzyme have only been obtained in limited amounts. We here report on the heterologous production of ProDH from Thermus thermophilus (TtProDH) in Escherichia coli. Using maltose-binding protein as solubility tag, high yields of active holoenzyme are obtained. Native TtProDH can be produced from cleaving the purified fusion protein with trypsin. Size-exclusion chromatography shows that fused and clipped TtProDH form oligomers. Thermal stability and co-solvent tolerance indicate the conformational robustness of TtProDH. These properties together with the high yield make TtProDH attractive for industrial applications.

  19. Correlation between viscous-flow activation energy and phase diagram in four systems of Cu-based alloys

    NASA Astrophysics Data System (ADS)

    Ning, Shuang; Bian, Xiufang; Ren, Zhenfeng

    2010-09-01

    Activation energy is obtained from temperature dependence of viscosities by means of a fitting to the Arrhenius equation for liquid alloys of Cu-Sb, Cu-Te, Cu-Sn and Cu-Ag systems. We found that the changing trend of activation energy curves with concentration is similar to that of liquidus in the phase diagrams. Moreover, a maximum value of activation energy is in the composition range of the intermetallic phases and a minimum value of activation energy is located at the eutectic point. The correlation between the activation energy and the phase diagrams has been further discussed.

  20. Assessment of Uncertainty in the Determination of Activation Energy for Polymeric Materials

    NASA Technical Reports Server (NTRS)

    Darby, Stephania P.; Landrum, D. Brian; Coleman, Hugh W.

    1998-01-01

    An assessment of the experimental uncertainty in obtaining the kinetic activation energy from thermogravimetric analysis (TGA) data is presented. A neat phenolic resin, Borden SC1O08, was heated at three heating rates to obtain weight loss vs temperature data. Activation energy was calculated by two methods: the traditional Flynn and Wall method based on the slope of log(q) versus 1/T, and a modification of this method where the ordinate and abscissa are reversed in the linear regression. The modified method produced a more accurate curve fit of the data, was more sensitive to data nonlinearity, and gave a value of activation energy 75 percent greater than the original method. An uncertainty analysis using the modified method yielded a 60 percent uncertainty in the average activation energy. Based on this result, the activation energy for a carbon-phenolic material was doubled and used to calculate the ablation rate In a typical solid rocket environment. Doubling the activation energy increased surface recession by 3 percent. Current TGA data reduction techniques that use the traditional Flynn and Wall approach to calculate activation energy should be changed to the modified method.

  1. Effect of alloying on the self-diffusion activation energy in γ-iron

    NASA Astrophysics Data System (ADS)

    Vasilyev, A. A.; Sokolov, S. F.; Kolbasnikov, N. G.; Sokolov, D. F.

    2011-11-01

    The experimental data on the self-diffusion coefficient of austenite with different chemical compositions obtained by the radioactive isotope method have been analyzed quantitatively. The self-diffusion activation energy in pure γ-iron is shown to be ˜312 kJ/mol. Alloying of austenite with such elements as Mn, Mo, Nb, Ti, and Si (to a lower degree) increases the self-diffusion activation energy, and alloying with C, V, or Cr (for the element content ≥3 at %) decreases it. The empirical formula is derived for calculation of the self-diffusion activation energy in austenite solid solutions with complex composition.

  2. The Activation Energy Of Ignition Calculation For Materials Based On Plastics

    NASA Astrophysics Data System (ADS)

    Rantuch, Peter; Wachter, Igor; Martinka, Jozef; Kuracina, Marcel

    2015-06-01

    This article deals with the activation energy of ignition calculation of plastics. Two types of polyamide 6 and one type of polypropylene and polyurethane were selected as samples. The samples were tested under isothermal conditions at several temperatures while times to ignition were observed. From the obtained data, activation energy relating to the moment of ignition was calculated for each plastics. The values for individual plastics were different. The highest activation energies (129.5 kJ.mol-1 and 106.2 kJ.mol-1) were achieved by polyamides 6, while the lowest was determined for a sample of polyurethane.

  3. Trypanosoma cruzi: antiprotozoal activity of parthenolide obtained from Tanacetum parthenium (L.) Schultz Bip. (Asteraceae, Compositae) against epimastigote and amastigote forms.

    PubMed

    Izumi, Erika; Morello, Luis Gustavo; Ueda-Nakamura, Tânia; Yamada-Ogatta, Sueli Fumie; Filho, Benedito Prado Dias; Cortez, Diógenes Aparício Garcia; Ferreira, Izabel Cristina Piloto; Morgado-Díaz, José Andrés; Nakamura, Celso Vataru

    2008-03-01

    This study reports the activity of crude extracts, fractions and parthenolide (pure compound) obtained from Tanacetum parthenium against two forms of the parasite Trypanosoma cruzi. Feverfew is a traditional herbal medicine that has been used for the treatment of migraine, fever and arthritis. Activity against epimastigote forms was observed for crude extracts, fractions and parthenolide, and a progressive increase in the antitrypanosomal effect was observed in the course of the purification process. The pure compound showed IC50/96h and IC90/96h of 0.5 microg/ml and 1.25 microg/ml, respectively. The cytotoxic effect of parthenolide in LLMCK2 cells was 3.2 microg/ml (CC50/96h) and the selectivity index was 6.4. No hemolysis was detected for the pure compound. The internalization index of T. cruzi in LLMCK2 cells was reduced almost 51% at the concentration of 2 microg/ml of parthenolide, and 96.6% at 4 microg/ml. Scanning and transmission electron microscopy permitted observation of morphological modifications and ultrastructural alterations.

  4. Effects of Temperature and Pore Structure on High Surface Area-Activated Carbon Obtained from Peanut Shells.

    PubMed

    Kalpana, D; Lee, Y S

    2016-03-01

    Activated carbon was synthesized from peanut shells by treating with H3PO4 with an intention to enhance the surface area and to find its electrochemical performance in EDLC as electrode material. The powdered peanut shells were pyrolyzed at three different temperatures namely 300 degrees C, 600 degrees C and 800 degrees C respectively. The structural and surface properties of the pyrolyzed carbon materials were studied using N2 adsorption/desorption, Raman, TEM and SEM analysis. There has been remarkable increase in the surface area of the carbon pyrolyzed at 600 degrees C due to the effect of pore generations. The surface area of the 600 degrees C pyrolyzed sample was found to be 1629 m2/g. The electrochemical properties of all the samples were evaluated by cyclic voltammetry, impedance spectroscopy, and galvanostatic charge-discharge tests. The system showed excellent cycleability and a maximum specific capacitance of 291 Fg(-1) was obtained in a 0.1 M H2SO4 electrolyte solution. The effects of the various properties of the activated carbon on the EDLC performance are discussed.

  5. Erythrocytes and cell line-based assays to evaluate the cytoprotective activity of antioxidant components obtained from natural sources.

    PubMed

    Botta, Albert; Martínez, Verónica; Mitjans, Montserrat; Balboa, Elena; Conde, Enma; Vinardell, M Pilar

    2014-02-01

    Oxidative stress can damage cellular components including DNA, proteins or lipids, and may cause several skin diseases. To protect from this damage and addressing consumer's appeal to natural products, antioxidants obtained from algal and vegetal extracts are being proposed as antioxidants to be incorporated into formulations. Thus, the development of reliable, quick and economic in vitro methods to study the cytoactivity of these products is a meaningful requirement. A combination of erythrocyte and cell line-based assays was performed on two extracts from Sargassum muticum, one from Ulva lactuca, and one from Castanea sativa. Antioxidant properties were assessed in erythrocytes by the TBARS and AAPH assays, and cytotoxicity and antioxidant cytoprotection were assessed in HaCaT and 3T3 cells by the MTT assay. The extracts showed no antioxidant activity on the TBARS assay, whereas their antioxidant capacity in the AAPH assay was demonstrated. On the cytotoxicity assays, extracts showed low toxicity, with IC50 values higher than 200μg/mL. C. sativa extract showed the most favourable antioxidant properties on the antioxidant cytoprotection assays; while S. muticum and U. lactuca extracts showed a slight antioxidant activity. This battery of methods was useful to characterise the biological antioxidant properties of these natural extracts.

  6. Selected Energy Education Activities for Pennsylvania Middle School Grades. Draft.

    ERIC Educational Resources Information Center

    Hack, Nancy; And Others

    These activities are intended to help increase awareness and understanding of the energy situation and to encourage students to become energy conservationists. The document is divided into sections according to discipline area. A final section is devoted to interdisciplinary activities involving several discipline areas integrated with the energy…

  7. Lightstick Magic: Determination of the Activation Energy with PSL.

    ERIC Educational Resources Information Center

    Bindel, Thomas H.

    1996-01-01

    Presents experiments with lightsticks in which the activation energy for the light-producing reaction is determined. Involves monitoring the light intensity of the lightstick as a function of temperature. Gives students the opportunity to explore the concepts of kinetics and activation energies and the world of computer-interfaced experimentation…

  8. Fabric-based integrated energy devices for wearable activity monitors.

    PubMed

    Jung, Sungmook; Lee, Jongsu; Hyeon, Taeghwan; Lee, Minbaek; Kim, Dae-Hyeong

    2014-09-01

    A wearable fabric-based integrated power-supply system that generates energy triboelectrically using human activity and stores the generated energy in an integrated supercapacitor is developed. This system can be utilized as either a self-powered activity monitor or as a power supply for external wearable sensors. These demonstrations give new insights for the research of wearable electronics.

  9. Biomass I. Science Activities in Energy [and] Teacher's Guide.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Designed for science students in fourth, fifth, and sixth grades, the activities in this unit illustrate principles and problems related to biomass as a form of energy. (The word biomass is used to describe all solid material of animal or vegetable origin from which energy may be extracted.) Twelve student activities using art, economics,…

  10. Energy Conservation Activity Packet, Grade 3. Revised Edition.

    ERIC Educational Resources Information Center

    Pohlman, Betty; And Others

    This notebook for grade 3 is one of a series developed in response to the concern for energy conservation. It contains activities that stress an energy conservation ethic and includes many values clarification activities for grade three. The packet is divided into two parts and provides the teacher with background information, concepts and…

  11. Energy Conservation Activities for Elementary Grades (Or: How To Help Slim Down the Energy Monster). Iowa Developed Energy Activities Sampler, Primary K-2. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This booklet provides activities for teachers to use in the primary elementary grades (K-2). The activities are organized into nine units, with units 1 through 8 containing three activities…

  12. Energy Conservation Activities for Elementary Grades (Or: How to Help Slim Down the Energy Monster). Iowa Developed Energy Activities Sampler, Primary K-2.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines. Div. of Instructional Services.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This booklet provides activities for teachers to use in the primary elementary grades (K-2). The activities are organized into nine units, with units I through VIII containing three…

  13. Energy Conservation Teaching Activities for Home Economics Classrooms.

    ERIC Educational Resources Information Center

    Jedlicka, Ella, Ed.

    This collection of home economics activities is intended to meet the special needs of home economics teachers who wish to include energy education activities in their curricula. The 45 activities can be used as presented, or can be modified to individual needs or local conditions. Each activity includes: (1) title, (2) objective, (3) activity…

  14. Solar Energy Education. Home economics: student activities. Field test edition

    SciTech Connect

    Not Available

    1981-03-01

    A view of solar energy from the standpoint of home economics is taken in this book of activities. Students are provided information on solar energy resources while performing these classroom activities. Instructions for the construction of a solar food dryer and a solar cooker are provided. Topics for study include window treatments, clothing, the history of solar energy, vitamins from the sun, and how to choose the correct solar home. (BCS)

  15. Comparative studies on adsorptive removal of heavy metal ions by biosorbent, bio-char and activated carbon obtained from low cost agro-residue.

    PubMed

    Kırbıyık, Çisem; Pütün, Ayşe Eren; Pütün, Ersan

    2016-01-01

    In this study, Fe(III) and Cr(III) metal ion adsorption processes were carried out with three adsorbents in batch experiments and their adsorption performance was compared. These adsorbents were sesame stalk without pretreatment, bio-char derived from thermal decomposition of biomass, and activated carbon which was obtained from chemical activation of biomass. Scanning electron microscopy and Fourier transform-infrared techniques were used for characterization of adsorbents. The optimum conditions for the adsorption process were obtained by observing the influences of solution pH, adsorbent dosage, initial solution concentration, contact time and temperature. The optimum adsorption efficiencies were determined at pH 2.8 and pH 4.0 for Fe(III) and Cr(III) metal ion solutions, respectively. The experimental data were modelled by different isotherm models and the equilibriums were well described by the Langmuir adsorption isotherm model. The pseudo-first-order, pseudo-second-order kinetic, intra-particle diffusion and Elovich models were applied to analyze the kinetic data and to evaluate rate constants. The pseudo-second-order kinetic model gave a better fit than the others. The thermodynamic parameters, such as Gibbs free energy change ΔG°, standard enthalpy change ΔH° and standard entropy change ΔS° were evaluated. The thermodynamic study showed the adsorption was a spontaneous endothermic process.

  16. Power spectral analysis of EEG activity obtained from cortical and subcortical sites during the vigilance states of the cat.

    PubMed

    Bronzino, J D; Stern, W C; Leahy, J P; Morgane, P J

    1976-01-01

    There is considerable evidence that the raphé system and the region of the nucleus tractus solitarious (NTS), including the area postrema, play significant roles in slow-wave sleep mechanisms and in EEG synchronization. Studies of the interactions between these systems and the neocortex are much needed. If neuronal activity in these lower brainstem regions regulates the degree of cortical synchrony then a high degree of correspondence between the EEG of the area postrema or raphé complex with that of the cortex might be expected. In order to quantitate the reequency characteristics of the EEG obtained from these subcortical sites (nucleus raphé dorsalis, area postrema, as well as anatomical controls adjacent to these regions) during the different vigilance states (waking, slow-wave sleep, REM sleep) in the cat, power spectral analyses techniques were employed. Comparison of these subcortical spectral characteristic with those obtained from cortical (frontal and occipital) sites during the same vigilance state, show that the spectral measures elicited from the region of the area postrema closely correspond to that of the cortex, particularly during slow-wave sleep. On the other hand, the EEG of the anterior portion of the raphé region, although exhibiting a substantial low frequency component during slow-wave sleep in comparison to wakefulness does not show a statistically significant shift to low frequencies such as occurs in the area postrema or the cortex. These results suggest that the increases in the low frequency content of the cortical EEG sites during slow-wave sleep results from synchronizing inputs from the area postrema to a greater extent than from the raphé complex.

  17. Molecular dynamics investigations of the dissociation of SiO2 on an ab initio potential energy surface obtained using neural network methods.

    PubMed

    Agrawal, Paras M; Raff, Lionel M; Hagan, Martin T; Komanduri, Ranga

    2006-04-07

    The neural network (NN) procedure to interpolate ab initio data for the purpose of molecular dynamics (MD) simulations has been tested on the SiO(2) system. Unlike other similar NN studies, here, we studied the dissociation of SiO(2) without the initial use of any empirical potential. During the dissociation of SiO(2) into Si+O or Si+O(2), the spin multiplicity of the system changes from singlet to triplet in the first reaction and from singlet to pentet in the second. This paper employs four potential surfaces. The first is a NN fit [NN(STP)] to a database comprising the lowest of the singlet, triplet, and pentet energies obtained from density functional calculations in 6673 nuclear configurations. The other three potential surfaces are obtained from NN fits to the singlet, triplet, and pentet-state energies. The dissociation dynamics on the singlet-state and NN(STP) surfaces are reported. The results obtained using the singlet surface correspond to those expected if the reaction were to occur adiabatically. The dynamics on the NN(STP) surface represent those expected if the reaction follows a minimum-energy pathway. This study on a small system demonstrates the application of NNs for MD studies using ab initio data when the spin multiplicity of the system changes during the dissociation process.

  18. Molecular dynamics investigations of the dissociation of SiO2 on an ab initio potential energy surface obtained using neural network methods

    NASA Astrophysics Data System (ADS)

    Agrawal, Paras M.; Raff, Lionel M.; Hagan, Martin T.; Komanduri, Ranga

    2006-04-01

    The neural network (NN) procedure to interpolate ab initio data for the purpose of molecular dynamics (MD) simulations has been tested on the SiO2 system. Unlike other similar NN studies, here, we studied the dissociation of SiO2 without the initial use of any empirical potential. During the dissociation of SiO2 into Si +O or Si +O2, the spin multiplicity of the system changes from singlet to triplet in the first reaction and from singlet to pentet in the second. This paper employs four potential surfaces. The first is a NN fit [NN(STP)] to a database comprising the lowest of the singlet, triplet, and pentet energies obtained from density functional calculations in 6673 nuclear configurations. The other three potential surfaces are obtained from NN fits to the singlet, triplet, and pentet-state energies. The dissociation dynamics on the singlet-state and NN(STP) surfaces are reported. The results obtained using the singlet surface correspond to those expected if the reaction were to occur adiabatically. The dynamics on the NN(STP) surface represent those expected if the reaction follows a minimum-energy pathway. This study on a small system demonstrates the application of NNs for MD studies using ab initio data when the spin multiplicity of the system changes during the dissociation process.

  19. Gastroprotective effect of alpha-pinene and its correlation with antiulcerogenic activity of essential oils obtained from Hyptis species

    PubMed Central

    Pinheiro, Marcelo de Almeida; Magalhães, Rafael Matos; Torres, Danielle Mesquita; Cavalcante, Rodrigo Cardoso; Mota, Francisca Sheila Xavier; Oliveira Coelho, Emanuela Maria Araújo; Moreira, Henrique Pires; Lima, Glauber Cruz; Araújo, Pamella Cristina da Costa; Cardoso, José Henrique Leal; de Souza, Andrelina Noronha Coelho; Diniz, Lúcio Ricardo Leite

    2015-01-01

    Background: Alpha-pinene (α-pinene) is a monoterpene commonly found in essential oils with gastroprotective activity obtained from diverse medicinal plants, including Hyptis species. The genus Hyptis (lamiaceae) consists of almost 400 species widespread in tropical and temperate regions of America. In the north and northeastern Brazil, some Hyptis species are used in traditional medicine to treat gastrointestinal disturbances. Objective: The present study has investigated the gastoprotective effect of purified α-pinene in experimental gastric ulcer induced by ethanol and indomethacin in mice. Materials and Methods: Gastric ulcers were induced in male Swiss mice (20-30 g) by oral administration of absolute ethanol or indomethacin 45 min after oral pretreatment with vehicle, standard control drugs or α-pinene (10, 30, and 100 mg/kg). One hour after the ulcerative challenges, the stomach were removed, and gastric lesions areas measured. The effects of α-pinene on the gastric juice acidity were determined by pylorus ligation model. The gastrointestinal motility and mucus depletion were determined by measuring the gastric levels of phenol red and alcian blue, respectively. Hematoxylin and eosin stained sections of gastric mucosa of the experimental groups were used for histology analysis. Results: α-pinene pretreatment inhibited ethanol-induced gastric lesions, reduced volume and acidity of the gastric juice and increased gastric wall mucus (P < 0.05). Furthermore, we showed an interesting correlation between concentration of α-pinene and gastroprotective effect of Hyptis species (P Pearson = 0.98). Conclusion: Our data showed that the α-pinene exhibited significant antiulcerogenic activity and a great correlation between concentration of α-pinene and gastroprotective effect of Hyptis species was also observed. PMID:25709221

  20. Gastroprotective activity of alkaloid extract and 2-phenylquinoline obtained from the bark of Galipea longiflora Krause (Rutaceae).

    PubMed

    Zanatta, Francielle; Gandolfi, Renan Becker; Lemos, Marivane; Ticona, Juan Carlos; Gimenez, Alberto; Clasen, Bruna Kurz; Cechinel Filho, Valdir; de Andrade, Sérgio Faloni

    2009-07-15

    As part of our continuing search for bioactive natural products from plants, the present study was carried out in order to evaluate the gastroprotective properties of alkaloid extract and 2-phenylquinoline obtained from the bark of Galipea longiflora (Rutaceae). Anti-ulcer assays were performed using the following protocols in mice: nonsteroidal anti-inflammatory drug (NSAID)/bethanecol-induced ulcer, ethanol/HCl-induced ulcer, and stress-induced ulcer. The effects of the extract on gastric content volume, pH and total acidity were also evaluated, using the pylorus ligated model. Treatment using doses of 50, 125 and 250 mg/kg of G. longiflora alkaloid extract and positive controls (omeprazol or cimetidine) significantly diminished the lesion index, total lesion area, and percentage of lesion, in comparison with the negative control groups in all the models evaluated. Regarding the model of gastric secretion, a reduction in volume of gastric juice and total acidity was observed, as well as an increase in gastric pH. The main alkaloid of the plant, 2-phenylquinoline, was also evaluated in the ethanol-induced ulcer model. The results showed that at a dose of 50 mg/kg, it significantly inhibited ulcerative lesions. However, this effect was less than that of the alkaloid extract. All these results taken together show that G. longiflora displays gastroprotective activity, as evidenced by its significant inhibition of the formation of ulcers induced by different models. There are indications that mechanisms involved in anti-ulcer activity are related to a decrease in gastric secretion and an increase in gastric mucus content. Also, there is evidence of involvement of NO in the gastroprotector mechanisms. These effects may be attributed, at least in part, to the presence of some alkaloids, particularly 2-phenylquinoline.

  1. Impaired APP activity and altered Tau splicing in embryonic stem cell-derived astrocytes obtained from an APPsw transgenic minipig

    PubMed Central

    Hall, Vanessa J.; Lindblad, Maiken M.; Jakobsen, Jannik E.; Gunnarsson, Anders; Schmidt, Mette; Rasmussen, Mikkel A.; Volke, Daniela; Zuchner, Thole; Hyttel, Poul

    2015-01-01

    ABSTRACT Animal models of familial juvenile onset of Alzheimer's disease (AD) often fail to produce diverse pathological features of the disease by modification of single gene mutations that are responsible for the disease. They can hence be poor models for testing and development of novel drugs. Here, we analyze in vitro-produced stem cells and their derivatives from a large mammalian model of the disease created by overexpression of a single mutant human gene (APPsw). We produced hemizygous and homozygous radial glial-like cells following culture and differentiation of embryonic stem cells (ESCs) isolated from embryos obtained from mated hemizygous minipigs. These cells were confirmed to co-express varying neural markers, including NES, GFAP and BLBP, typical of type one radial glial cells (RGs) from the subgranular zone. These cells had altered expression of CCND1 and NOTCH1 and decreased expression of several ribosomal RNA genes. We found that these cells were able to differentiate into astrocytes upon directed differentiation. The astrocytes produced had decreased α- and β-secretase activity, increased γ-secretase activity and altered splicing of tau. This indicates novel aspects of early onset mechanisms related to cell renewal and function in familial AD astrocytes. These outcomes also highlight that radial glia could be a potentially useful population of cells for drug discovery, and that altered APP expression and altered tau phosphorylation can be detected in an in vitro model of the disease. Finally, it might be possible to use large mammal models to model familial AD by insertion of only a single mutation. PMID:26398935

  2. Antifungal, antiradical and cytotoxic activities of extractives obtained from Tagetes patula L. (Asteraceae), a potential acaricide plant species.

    PubMed

    Politi, Flávio A S; Queiroz-Fernandes, Geisiany M; Rodrigues, Edvânio R; Freitas, Jolindo A; Pietro, Rosemeire C L R

    2016-06-01

    Tagetes patula L. shows a complex chemical composition, ranging from glycosylated flavonoids and thiophenes in extracts until terpenoids in the essential oil. In the present study, due to this rich flavonoidic constitution, its antioxidant potential was determined, having shown values of antiradical percentage superior to reference compounds, mainly the extracts prepared with flowers. Previous studies performed emphasized the acaricide potential of T. patula and thus, the present study aimed to verify the action of extractives obtained from aerial parts on growth of entomopathogenic fungi related to biological control of brown dog tick Rhipicephalus sanguineus and the action against pathogenic fungi closely associated with pets. None of the samples inhibited the growth of strains of Beauveria bassiana or Metarhizium anisopliae, enabling feasible future studies of synergism on acaricide activity of formulations containing fungi and extracts. The antimicrobial activity of ethanolic extract of flowers (FlEtOH70%) against Microsporum canis and Trichophyton rubrum was significant (193.3 μg/mL and 253.9 μg/mL, respectively), as well as ethanolic extract from aerial parts (APEtOH70%) against T. rubrum (312.5 μg/mL). In order to ensure the safety of a topical formulation containing the extractives of T. patula, the cytotoxic potential of these samples were tested in murine macrophages cells. At higher concentrations all extracts were quite lethal, with IC50 ranging from 210.96 μg/mL to 468.75 μg/mL for APEtOH70% and FlEtOH70%, respectively. These results suggest that the application of a product containing T. patula extractives in the control of ticks could be used, at principle, only on the environment.

  3. Third-Order Incremental Dual-Basis Set Zero-Buffer Approach: An Accurate and Efficient Way To Obtain CCSD and CCSD(T) Energies.

    PubMed

    Zhang, Jun; Dolg, Michael

    2013-07-09

    An efficient way to obtain accurate CCSD and CCSD(T) energies for large systems, i.e., the third-order incremental dual-basis set zero-buffer approach (inc3-db-B0), has been developed and tested. This approach combines the powerful incremental scheme with the dual-basis set method, and along with the new proposed K-means clustering (KM) method and zero-buffer (B0) approximation, can obtain very accurate absolute and relative energies efficiently. We tested the approach for 10 systems of different chemical nature, i.e., intermolecular interactions including hydrogen bonding, dispersion interaction, and halogen bonding; an intramolecular rearrangement reaction; aliphatic and conjugated hydrocarbon chains; three compact covalent molecules; and a water cluster. The results show that the errors for relative energies are <1.94 kJ/mol (or 0.46 kcal/mol), for absolute energies of <0.0026 hartree. By parallelization, our approach can be applied to molecules of more than 30 atoms and more than 100 correlated electrons with high-quality basis set such as cc-pVDZ or cc-pVTZ, saving computational cost by a factor of more than 10-20, compared to traditional implementation. The physical reasons of the success of the inc3-db-B0 approach are also analyzed.

  4. Progress in obtaining an absolute calibration of a total deuterium-tritium neutron yield diagnostic based on copper activation.

    PubMed

    Ruiz, C L; Chandler, G A; Cooper, G W; Fehl, D L; Hahn, K D; Leeper, R J; McWatters, B R; Nelson, A J; Smelser, R M; Snow, C S; Torres, J A

    2012-10-01

    The 350-keV Cockroft-Walton accelerator at Sandia National laboratory's Ion Beam facility is being used to calibrate absolutely a total DT neutron yield diagnostic based on the (63)Cu(n,2n)(62)Cu(β+) reaction. These investigations have led to first-order uncertainties approaching 5% or better. The experiments employ the associated-particle technique. Deuterons at 175 keV impinge a 2.6 μm thick erbium tritide target producing 14.1 MeV neutrons from the T(d,n)(4)He reaction. The alpha particles emitted are measured at two angles relative to the beam direction and used to infer the neutron flux on a copper sample. The induced (62)Cu activity is then measured and related to the neutron flux. This method is known as the F-factor technique. Description of the associated-particle method, copper sample geometries employed, and the present estimates of the uncertainties to the F-factor obtained are given.

  5. Energy monitoring system based on human activity in the workplace

    NASA Astrophysics Data System (ADS)

    Mustafa, Nur Hanim; Husain, Mohd Nor; Aziz, Mohamad Zoinol Abidin Abdul; Othman, Mohd Azlishah; Malek, Fareq

    2015-05-01

    Human behaviors always related to day routine activities in a smart house directly give the significant factor to manage energy usage in human life. An Addition that, the factor will contribute to the best efficiency of the system. This paper will focus on the monitoring efficiency based on duration time in office hours around 8am until 5pm which depend on human behavior at working place. Besides that, the correlation coefficient method is used to show the relation between energy consumption and energy saving based on the total hours of time energy spent. In future, the percentages of energy monitoring system usage will be increase to manage energy saving based on human behaviors. This scenario will help to see the human activity in the workplace in order to get the energy saving and support world green environment.

  6. Photospheric Magnetic Free Energy Density of Solar Active Regions

    NASA Astrophysics Data System (ADS)

    Zhang, Hongqi

    2016-12-01

    We present the photospheric energy density of magnetic fields in two solar active regions (one of them recurrent) inferred from observational vector magnetograms, and compare it with other available differently defined energy parameters of magnetic fields in the photosphere. We analyze the magnetic fields in Active Regions NOAA 6580-6619-6659 and 11158. The quantity 1/4π{B}n\\cdot{B}p is an important energy parameter that reflects the contribution of magnetic shear to the difference between the potential (Bp) and the non-potential magnetic field (Bn), and also the contribution to the free magnetic energy near the magnetic neutral lines in the active regions. It is found that the photospheric mean magnetic energy density shows clear changes before the powerful solar flares in Active Region NOAA 11158, which is consistent with the change in magnetic fields in the flaring lower atmosphere.

  7. Phase transformations during HLnTiO{sub 4} (Ln=La, Nd) thermolysis and photocatalytic activity of obtained compounds

    SciTech Connect

    Silyukov, Oleg I. Abdulaeva, Liliia D.; Burovikhina, Alena A.; Rodionov, Ivan A.; Zvereva, Irina A.

    2015-03-15

    Layered HLnTiO{sub 4} (Ln=La, Nd) compounds belonging to Ruddlesden–Popper phases were found to form partially hydrated compounds Ln{sub 2}Ti{sub 2}O{sub 7}·xH{sub 2}O during thermal dehydration as well as defect oxides Ln{sub 2}□Ti{sub 2}O{sub 7} as final products. Further heating of metastable defect Ln{sub 2}□Ti{sub 2}O{sub 7} substances leads to the formation of pyrochlore-type oxides Ln{sub 2}Ti{sub 2}O{sub 7} {sub (p)}, with subsequent transformation under higher temperatures to stable layered 110-type perovskites Ln{sub 2}Ti{sub 2}O{sub 7}. The occurring structure transformations lead to an increase of photocatalytic activity in the order of HLnTiO{sub 4}activity in the order of HLnTiO{sub 4}obtained. • We examined the photocatalytic activity of all obtained compounds. The hydrogen evolution rate increased in the course of the structure changes during thermolysis.

  8. On the possibility of negative activation energies in bimolecular reactions

    NASA Technical Reports Server (NTRS)

    Jaffe, R. L.

    1978-01-01

    The temperature dependence of the rate constants for model reacting systems was studied to understand some recent experimental measurements which imply the existence of negative activation energies. A collision theory model and classical trajectory calculations are used to demonstrate that the reaction probability can vary inversely with collision energy for bimolecular reactions occurring on attractive potential energy surfaces. However, this is not a sufficient condition to ensure that the rate constant has a negative temperature dependence. On the basis of these calculations, it seems unlikely that a true bimolecular reaction between neutral molecules will have a negative activation energy.

  9. Energy.

    ERIC Educational Resources Information Center

    Online-Offline, 1998

    1998-01-01

    This issue focuses on the theme of "Energy," and describes several educational resources (Web sites, CD-ROMs and software, videos, books, activities, and other resources). Sidebars offer features on alternative energy, animal energy, internal combustion engines, and energy from food. Subthemes include harnessing energy, human energy, and…

  10. Hybrid energy storage systems utilizing redox active organic compounds

    SciTech Connect

    Wang, Wei; Xu, Wu; Li, Liyu; Yang, Zhenguo

    2015-09-08

    Redox flow batteries (RFB) have attracted considerable interest due to their ability to store large amounts of power and energy. Non-aqueous energy storage systems that utilize at least some aspects of RFB systems are attractive because they can offer an expansion of the operating potential window, which can improve on the system energy and power densities. One example of such systems has a separator separating first and second electrodes. The first electrode includes a first current collector and volume containing a first active material. The second electrode includes a second current collector and volume containing a second active material. During operation, the first source provides a flow of first active material to the first volume. The first active material includes a redox active organic compound dissolved in a non-aqueous, liquid electrolyte and the second active material includes a redox active metal.

  11. Energy Consumption of Actively Beating Flagella

    NASA Astrophysics Data System (ADS)

    Chen, Daniel; Nicastro, Daniela; Dogic, Zvonimir

    2012-02-01

    Motile cilia and flagella are important for propelling cells or driving fluid over tissues. The microtubule-based core in these organelles, the axoneme, has a nearly universal ``9+2'' arrangement of 9 outer doublet microtubules assembled around two singlet microtubules in the center. Thousands of molecular motor proteins are attached to the doublets and walk on neighboring outer doublets. The motors convert the chemical energy of ATP hydrolysis into sliding motion between adjacent doublet microtubules, resulting in precisely regulated oscillatory beating. Using demembranated sea urchin sperm flagella as an experimental platform, we simultaneously monitor the axoneme's consumption of ATP and its beating dynamics while key parameters, such as solution viscosity and ATP concentration, are varied. Insights into motor cooperativity during beating and energetic consequences of hydrodynamic interactions will be presented.

  12. Energy Around Us. A Fall Activity Packet for Fourth Grade.

    ERIC Educational Resources Information Center

    Jackson Community Coll., MI. Dahlem Environmental Education Center.

    This instructional packet is one of 14 school environmental education programs developed for use in the classroom and at the Dahlem Environmental Education Center (DEEC) of the Jackson Community College (Michigan). Provided in the packet are pre-trip activities, field trip activities, and post-trip activities which focus on energy uses, energy…

  13. Thermopower and conductivity activation energies in hydrogenated amorphous silicon

    SciTech Connect

    Dyalsingh, H.M.; Kakalios, J.

    1996-12-31

    The long range fluctuation model has been widely used to account for the difference in activation energies seen experimentally in dark conductivity and thermopower measurements in hydrogenated amorphous silicon. The authors report on a test of this model using measurements of the conductivity and thermoelectric effects carried out in both open and short circuit configurations. While the thermopower activation energy is less than that of the dark conductivity, the short circuit Seebeck conductivity is found to be nearly identical to the dark conductivity in both activation energy and magnitude, consistent with the long range fluctuation model.

  14. Source spectra of the gravity waves obtained from momentum flux and kinetic energy over Indian region: Comparison between observations and model results

    NASA Astrophysics Data System (ADS)

    Pramitha, M.; Venkat Ratnam, M.; Krishna Murthy, B. V.; Vijaya Bhaskar Rao, S.

    2017-02-01

    Using 8 years (May 2006 to March 2014) of high resolution and high accuracy GPS radiosonde observations available from a tropical station Gadanki (13.5°N, 79.2°E), India, we have investigated the climatology of gravity wave energy and zonal momentum fluxes in the lower stratosphere. We also obtained best fit spectrum model for the gravity waves (GWs) for this tropical station. In general, strong annual variation in the energy and momentum flux with maximum during Indian summer monsoon is observed in the lower stratospheric region (18-25 km). By considering different source spectra, we have applied Gravitywave Regional or Global RAy Tracer (GROGRAT) model run on monthly basis using the source spectrum values at different altitudes on the ERA-Interim background fields to obtain the kinetic energy and zonal momentum fluxes for each of the spectra considered. These simulated fluxes are compared with the observed fluxes to arrive at the best fit spectrum model. It is found that the spectrum which represents the convection transient mountain mechanism that is purely anti-symmetric and anisotropic in nature is the best fit model for Gadanki location. This information would be useful in parameterization of the GWs in numerical models over Indian region.

  15. The elastic modulus correction term in creep activation energies Applied to oxide dispersion strengthened superalloy

    NASA Technical Reports Server (NTRS)

    Malu, M.; Tien, J. K.

    1975-01-01

    The effect of elastic modulus and the temperature dependence of elastic modulus on creep activation energies for an oxide dispersion strengthened nickel-base superalloy are investigated. This superalloy is commercially known as Inconel Alloy MA 753, strengthened both by gamma-prime precipitates and by yttria particles. It is shown that at intermediate temperatures, say below 1500 F, where elastic modulus is weakly dependent on temperature, the modulus correction term to creep activation energy is small. Accordingly, modulus corrections are insignificant for the superalloy considered, which shows high apparent creep activation energies at this temperature. On the contrary, at very high temperatures, the elastic modulus correction term can be significant, thus reducing the creep activation energy to that of vacancy self-diffusion. In order to obtain high-temperature creep resistance, a high-value elastic modulus with a weak dependence on temperature is required.

  16. Using Microcomputers in the Physical Chemistry Laboratory: Activation Energy Experiment.

    ERIC Educational Resources Information Center

    Touvelle, Michele; Venugopalan, Mundiyath

    1986-01-01

    Describes a computer program, "Activation Energy," which is designed for use in physical chemistry classes and can be modified for kinetic experiments. Provides suggestions for instruction, sample program listings, and information on the availability of the program package. (ML)

  17. The Geography of Wind Energy: Problem Solving Activities.

    ERIC Educational Resources Information Center

    Lahart, David E.; Allen, Rodney F.

    1985-01-01

    Today there are many attempts to use wind machines to confront the increasing costs of electricity. Described are activities to help secondary students understand wind energy, its distribution, applications, and limitations. (RM)

  18. Highlands County Energy Education Activities--High School Level.

    ERIC Educational Resources Information Center

    Allen, Rodney F., Ed.

    Presented are five instructional units, developed by the Tri-County Teacher Education Center, for the purpose of educating secondary school students on Florida's unique energy problems. Unit one provides a series of value clarification and awareness activities as an introduction to energy. Unit two uses mathematics exercises to examine energy…

  19. Energy Conservation Activity Guide, Grades 9-12. Bulletin 1602.

    ERIC Educational Resources Information Center

    Fraser, Mollie; And Others

    As an interdisciplinary, non-sequential teaching guide, this publication was developed to increase awareness and understanding of the energy situation and to encourage individuals to become energy conservationists. Sections provide background information for the teacher followed by a variety of student activities using different subject areas for…

  20. Activity pattern and energy expenditure due to physical activity before and during pregnancy in healthy Swedish women.

    PubMed

    Lof, Marie; Forsum, Elisabet

    2006-02-01

    Human pregnancy is associated with increased requirements for dietary energy and this increase may be partly offset by reductions in physical activity during gestation. Studies in well-nourished women have shown that the physical activity level (PAL), obtained as the total energy expenditure (TEE) divided by the BMR, decreases in late pregnancy. However, it is not known if this decrease is really caused by reductions in physical activity or if it is the result of decreases in energy expenditure/BMR (the so-called metabolic equivalent, MET) for many activities in late pregnancy. In the present study activity pattern, TEE and BMR were assessed in twenty-three healthy Swedish women before pregnancy as well as in gestational weeks 14 and 32. Activity pattern was assessed using a questionnaire and heart rate recording. TEE was assessed using the doubly labelled water method and BMR was measured by means of indirect calorimetry. When compared to the pre-pregnant value, there was little change in the PAL in gestational week 14 but it was significantly reduced in gestational week 32. Results obtained by means of the questionnaire and by heart rate recording showed that the activity pattern was largely unaffected by pregnancy. The findings support the following conclusion: in a population of well-nourished women where the activity pattern is maintained during pregnancy, the increase in BMR represents approximately the main part of the pregnancy-induced increase in TEE, at least until gestational week 32.

  1. Data on energy-band-gap characteristics of composite nanoparticles obtained by modification of the amorphous potassium polytitanate in aqueous solutions of transition metal salts.

    PubMed

    Zimnyakov, D A; Sevrugin, A V; Yuvchenko, S A; Fedorov, F S; Tretyachenko, E V; Vikulova, M A; Kovaleva, D S; Krugova, E Y; Gorokhovsky, A V

    2016-06-01

    Here we present the data on the energy-band-gap characteristics of composite nanoparticles produced by modification of the amorphous potassium polytitanate in aqueous solutions of different transition metal salts. Band gap characteristics are investigated using diffuse reflection spectra of the obtained powders. Calculated logarithmic derivative quantity of the Kubelka-Munk function reveals a presence of local maxima in the regions 0.5-1.5 eV and 1.6-3.0 eV which correspond to band gap values of the investigated materials. The values might be related to the constituents of the composite nanoparticles and intermediate products of their chemical interaction.

  2. The activation energy for creep of columbium /niobium/.

    NASA Technical Reports Server (NTRS)

    Klein, M. J.; Gulden, M. E.

    1973-01-01

    The activation energy for creep of nominally pure columbium (niobium) was determined in the temperature range from 0.4 to 0.75 T sub M by measuring strain rate changes induced by temperature shifts at constant stress. A peak in the activation energy vs temperature curve was found with a maximum value of 160 kcal/mole. A pretest heat treatment of 3000 F for 30 min resulted in even higher values of activation energy (greater than 600 kcal/mole) in this temperature range. The activation energy for the heat-treated columbium (Nb) could not be determined near 0.5 T sub M because of unusual creep curves involving negligible steady-state creep rates and failure at less than 5% creep strain. It is suggested that the anomalous activation energy values and the unusual creep behavior in this temperature range are caused by dynamic strain aging involving substitutional atom impurities and that this type of strain aging may be in part responsible for the scatter in previously reported values of activation energy for creep of columbium (Nb) near 0.5 T sub M.

  3. Reactive Ni/Al Nanocomposites: Structural Characteristics and Activation Energy.

    PubMed

    Shuck, Christopher E; Mukasyan, Alexander S

    2017-02-16

    Stochastically structured Ni/Al reactive nanocomposites (RNCs) were prepared using short-term high-energy ball milling. Several milling times were utilized to prepare RNCs with differing internal nanostructures. These internal structures were quantitatively and statistically analyzed by use of serial focused ion beam sectioning coupled with 3D reconstruction techniques. The reaction kinetics were analyzed using the electrothermal explosion technique for each milling condition. It is shown that the effective activation energy (Eef) ranges from 79 to 137 kJ/mol and is directly related to the surface area contact between the reactants. Essentially, the reaction kinetics can be accurately controlled through mechanical processing techniques. Finally, the nature of the reaction is considered; the mechanistic effect of the reactive and three diffusive activation energies on the effective activation energy is examined.

  4. Annealing effect on the particle size and chemical composition of activated carbon obtained from vacuum furnace of teak sawdust

    NASA Astrophysics Data System (ADS)

    Armynah, B.; Tahir, D.; Jaya, N.

    2014-09-01

    Activated carbon was produced from sawdust by using physical method in a high temperature vacuum furnace without additional chemical. Fast pyrolysis process was carried out prior in fluidized a bed furnace to produce char before activation process. Experiments were conducted to investigate the influence of various process parameters such as particle size, activation temperature and activation time on the quality of the activated carbon. In addition, the chemical composition studies were done by using x-ray fluorescence (XRF) spectroscopy. The crystallite sizes were calculated by using Scherer equation based on x-ray diffraction (XRD) spectroscopy data. The pyrolysis temperature and time were varied from 600°C to 900°C and from 3 hours to 6 hours, respectively. The particle size of activated carbon was increase with increasing temperature. The composition and crystallite size of the prepared activated carbon was compared with the non-activated carbon. The results indicated that the teak sawdust carbon could be employed as a low cost alternative to produce commercial activated carbon.

  5. Annealing effect on the particle size and chemical composition of activated carbon obtained from vacuum furnace of teak sawdust

    SciTech Connect

    Armynah, B. Tahir, D. Jaya, N.

    2014-09-25

    Activated carbon was produced from sawdust by using physical method in a high temperature vacuum furnace without additional chemical. Fast pyrolysis process was carried out prior in fluidized a bed furnace to produce char before activation process. Experiments were conducted to investigate the influence of various process parameters such as particle size, activation temperature and activation time on the quality of the activated carbon. In addition, the chemical composition studies were done by using x-ray fluorescence (XRF) spectroscopy. The crystallite sizes were calculated by using Scherer equation based on x-ray diffraction (XRD) spectroscopy data. The pyrolysis temperature and time were varied from 600°C to 900°C and from 3 hours to 6 hours, respectively. The particle size of activated carbon was increase with increasing temperature. The composition and crystallite size of the prepared activated carbon was compared with the non-activated carbon. The results indicated that the teak sawdust carbon could be employed as a low cost alternative to produce commercial activated carbon.

  6. Conservation II. Science Activities in Energy. [Student's and] Teacher's Guide.

    ERIC Educational Resources Information Center

    Oak Ridge Associated Universities, TN.

    Designed for science students in fourth, fifth, and sixth grades, the activities in this unit illustrate principles and problems related to the conservation of energy. Eleven student activities using art, economics, arithmetic, and other skills and disciplines help teachers directly involve students in exploring scientific questions and making…

  7. Enzyme activation through the utilization of intrinsic dianion binding energy.

    PubMed

    Amyes, T L; Malabanan, M M; Zhai, X; Reyes, A C; Richard, J P

    2016-11-29

    We consider 'the proposition that the intrinsic binding energy that results from the noncovalent interaction of a specific substrate with the active site of the enzyme is considerably larger than is generally believed. An important part of this binding energy may be utilized to provide the driving force for catalysis, so that the observed binding energy represents only what is left over after this utilization' [Jencks,W.P. (1975) Adv. Enzymol. Relat. Areas. Mol. Biol., 43: , 219-410]. The large ~12 kcal/mol intrinsic substrate phosphodianion binding energy for reactions catalyzed by triosephosphate isomerase (TIM), orotidine 5'-monophosphate decarboxylase and glycerol-3-phosphate dehydrogenase is divided into 4-6 kcal/mol binding energy that is expressed on the formation of the Michaelis complex in anchoring substrates to the respective enzyme, and 6-8 kcal/mol binding energy that is specifically expressed at the transition state in activating the respective enzymes for catalysis. A structure-based mechanism is described where the dianion binding energy drives a conformational change that activates these enzymes for catalysis. Phosphite dianion plays the active role of holding TIM in a high-energy closed active form, but acts as passive spectator in showing no effect on transition-state structure. The result of studies on mutant enzymes is presented, which support the proposal that the dianion-driven enzyme conformational change plays a role in enhancing the basicity of side chain of E167, the catalytic base, by clamping the base between a pair of hydrophobic side chains. The insight these results provide into the architecture of enzyme active sites and the development of strategies for the de novo design of protein catalysts is discussed.

  8. World Energy Projection System Plus (WEPS ): Global Activity Module

    EIA Publications

    2016-01-01

    The World Energy Projection System Plus (WEPS ) is a comprehensive, mid?term energy forecasting and policy analysis tool used by EIA. WEPS projects energy supply, demand, and prices by country or region, given assumptions about the state of various economies, international energy markets, and energy policies. The Global Activity Module (GLAM) provides projections of economic driver variables for use by the supply, demand, and conversion modules of WEPS . GLAM’s baseline economic projection contains the economic assumptions used in WEPS to help determine energy demand and supply. GLAM can also provide WEPS with alternative economic assumptions representing a range of uncertainty about economic growth. The resulting economic impacts of such assumptions are inputs to the remaining supply and demand modules of WEPS .

  9. Let's Get Physical: K-12 Students Using Wearable Devices to Obtain and Learn about Data from Physical Activities

    ERIC Educational Resources Information Center

    Lee, Victor R.; Drake, Joel; Williamson, Kylie

    2015-01-01

    Accessibility to wearable technology has exploded in the last decade. As such, this technology has potential to be used in classrooms in uniquely interactive and personally meaningful ways. Seeing this as a possible future for schools, we have been exploring approaches for designing activities to incorporate wearable physical activity data…

  10. PVDF-HFP/ether-modified polysiloxane membranes obtained via airbrush spraying as active separators for application in lithium ion batteries.

    PubMed

    Seidel, S M; Jeschke, S; Vettikuzha, P; Wiemhöfer, H-D

    2015-08-04

    Improved hybrid polymer electrolyte membranes are introduced based on ether-modified polysiloxanes and poly(vinylidene fluoride-co-hexafluoropropylene) yielding a safe separator membrane, which is able to be sprayed directly onto lithium ion battery active materials, with an active role for enhanced ion transport.

  11. Animal-Assisted Activities for Students with Disabilities: Obtaining Stakeholders' Approval and Planning Strategies for Teachers

    ERIC Educational Resources Information Center

    Baumgartner, Erin; Cho, Jeong-il

    2014-01-01

    Animal-human interactions have been found to have positive influences on children across the world. In particular, research supports the benefits of animal-assisted activities in addressing students' social and behavioral problems within the classroom environment. The general information about animal-assisted activities provided in this…

  12. High-energy spectra of active nuclei. 1: The catalog

    NASA Technical Reports Server (NTRS)

    Malaguti, G.; Bassani, L.; Caroli, E.

    1994-01-01

    This paper presents a catalog of high-energy spectra (E is greater than or equal to 0.01 keV) of active galactic nuclei (AGNs). The catalog contains 209 objects (140 Seyfert galaxies, 65 quasars, and 4 objects otherwise classified), for a total of 1030 spectra. Most of the data have been collected from the literature over a period spanning more than 20 yr starting from the early 1970s up to the end of 1992. For a numbner of objects (17), EXOSAT/ME data have been extracted and analyzed, and the 27 spectra obtained have been added to the database. For each object we report individual observation spectral fit parameters using a power-law model corrected for cold gas absorption along the line of sight (photon index, 1 keV intensity and hydrogen column density), plus other relevant data. It is hoped that this database can become a useful tool for the study of the AGN phenomenon in its various aspects.

  13. Nematicidal and antimicrobial activities of methanol extracts of 17 plants, of importance in ethnopharmacology, obtained from the Arabian Peninsula

    PubMed Central

    Al-Marby, Adel; Ejike, Chukwunonso ECC; Nasim, Muhammad Jawad; Awadh-Ali, Nasser A; Al-badani, Rwaida A; Alghamdi, Ghanem MA; Jacob, Claus

    2016-01-01

    Aim/Background: The development of resistance to synthetic drugs by target organisms is a major challenge facing medicine, yet locked within plants are phytochemicals used in herbal medicine (especially in the Arabian Peninsula) that may find application in this regard. In pursuit of unlocking these “hidden treasures,” the methanol extracts of leaves, aerial parts, fruits, and resins of 17 plants used in the Arabian Peninsula were screened for antimicrobial activities. Materials and Methods: The nematicidal, antibacterial, and antifungal activities were determined using appropriate assays. Steinernema feltiae, Staphylococcus carnosus, Escherichia coli, and Saccharomyces cerevisiae were used as test organisms. Concentrations of the extracts ranging from 0.5 to 20 mg/ml were tested and appropriate statistical tests performed on the data generated. Results: The results show that extracts from Solanum incanum, Chenopodium murale, Commiphora myrrha, Anthemis nobilis, and Achillea biebersteinii were the most active and had very high activities against two or more of the test organisms at low concentrations. Extracts of the leaves of S. incanum and resins of Ferula asafoetida were the most active nematicides, with significant activity at 0.5 mg/ml. Extracts of C. myrrha and C. murale had the most active antibacterial activity with inhibition zones of 12-15 mm and minimum inhibitory concentrations (MICs) of 2.5 mg/ml for both bacteria. Extracts of the leaves of A. biebersteinii were the most active fungicide, giving an MIC of 1.5 mg/ml. Conclusion: The results validate the use of these plants in ethnopharmacology, and open new vistas of opportunities for the development of cheap but effective agents that may be useful against infectious diseases. PMID:27104031

  14. Energy effective approach for activation of metallurgical slag

    NASA Astrophysics Data System (ADS)

    Mazov, I. N.; Khaydarov, B. B.; Mamulat, S. L.; Suvorov, D. S.; Saltikova, Y. S.; Yudin, A. G.; Kuznetsov, D. V.

    2016-01-01

    The paper presents results of investigation of the process of mechanical activation of metallurgical slag using different approaches - ball milling and electromagnetic vortex apparatus. Particle size distribution and structure of mechanically activated slag samples were investigated, as well as energetic parameters of the activation process. It was shown that electromagnetic vortex activation is more energy effective and allows to produce microscale milled slag-based concrete using very short treatment time. Activated slag materials can be used as clinker-free cement in civilian and road construction, providing ecology-friendly technology and recycling of high-tonnage industrial waste.

  15. A time to search: finding the meaning of variable activation energy.

    PubMed

    Vyazovkin, Sergey

    2016-07-28

    This review deals with the phenomenon of variable activation energy frequently observed when studying the kinetics in the liquid or solid phase. This phenomenon commonly manifests itself through nonlinear Arrhenius plots or dependencies of the activation energy on conversion computed by isoconversional methods. Variable activation energy signifies a multi-step process and has a meaning of a collective parameter linked to the activation energies of individual steps. It is demonstrated that by using appropriate models of the processes, the link can be established in algebraic form. This allows one to analyze experimentally observed dependencies of the activation energy in a quantitative fashion and, as a result, to obtain activation energies of individual steps, to evaluate and predict other important parameters of the process, and generally to gain deeper kinetic and mechanistic insights. This review provides multiple examples of such analysis as applied to the processes of crosslinking polymerization, crystallization and melting of polymers, gelation, and solid-solid morphological and glass transitions. The use of appropriate computational techniques is discussed as well.

  16. The activation energy for dislocation nucleation at a crack

    NASA Astrophysics Data System (ADS)

    Rice, James R.; Beltz, Glenn E.

    1994-02-01

    T HE ACTIVATION energy for dislocation nucleation from a stressed crack tip is calculated within the Peierls framework, in which a periodic shear stress vs displacement relation is assumed to hold on a slip plane emanating from the crack tip. Previous results have revealed that the critical G (energy release rate corresponding to the "screened" crack tip stress field) for dislocation nucleation scales with γ us (the unstable stacking energy), in an analysis which neglects any coupling between tension and shear along the slip plane. That analysis represents instantaneous nucleation and takes thermal effects into account only via the weak temperature dependence of the elastic constants. In this work, the energy required to thermally activate a stable, incipient dislocation into its unstable "saddle-point" configuration is directly calculated for loads less than that critical value. We do so only with the simplest case, for which the slip plane is a prolongation of the crack plane. A first calculation reported is 2D in nature, and hence reveals an activation energy per unit length. A more realistic scheme for thermal activation involves the emission of a dislocation loop, an inherently 3D phenomenon. Asymptotic calculations of the activation energy for loads close to the critical load are performed in 2D and in 3D. It is found that the 3D activation energy generally corresponds to the 2D activation energy per unit length multiplied by about 5-10 Burgers vectors (but by as many as 17 very near to the critical loading). Implications for the emission of dislocations in copper, α-iron, and silicon at elevated temperature are discussed. The effects of thermal activation are very significant in lowering the load for emission. Also, the appropriate activation energy to correspond to molecular dynamics simulations of crack tips is discussed. Such simulations, as typically carried out with only a few atomic planes in a periodic repeat direction parallel to the crack tip, are

  17. Active energy harvesting from microbial fuel cells at the maximum power point without using resistors.

    PubMed

    Wang, Heming; Park, Jae-Do; Ren, Zhiyong

    2012-05-01

    Microbial fuel cell (MFC) technology offers a sustainable approach to harvest electricity from biodegradable materials. Energy production from MFCs has been demonstrated using external resistors or charge pumps, but such methods can only dissipate energy through heat or receive electrons passively from the MFC without any controllability. This study developed a new approach and system that can actively extract energy from MFC reactors at any operating point without using any resistors, especially at the peak power point to maximize energy production. Results show that power harvesting from a recirculating-flow MFC can be well maintained by the maximum power point circuit (MPPC) at its peak power point, while a charge pump was not able to change operating point due to current limitation. Within 18-h test, the energy gained from the MPPC was 76.8 J, 76 times higher than the charge pump (1.0 J) that was commonly used in MFC studies. Both conditions resulted in similar organic removal, but the Coulombic efficiency obtained from the MPPC was 21 times higher than that of the charge pump. Different numbers of capacitors could be used in the MPPC for various energy storage requirements and power supply, and the energy conversion efficiency of the MPPC was further characterized to identify key factors for system improvement. This active energy harvesting approach provides a new perspective for energy harvesting that can maximize MFC energy generation and system controllability.

  18. Antiulcerogenic activity of crude ethanol extract and some fractions obtained from aerial parts of Artemisia annua L.

    PubMed

    Dias, P C; Foglio, M A; Possenti, A; Nogueira, D C; de Carvalho, J E

    2001-12-01

    The resulting enriched sesquiterpene lactone fraction and the crude ethanol extract of Artemisia annua L. aerial parts, showed antiulcerogenic activity when administered orally, on the indomethacin induced ulcer in rats. The sesquiterpene lactone fraction yielded three different polarity fractions on column chromatography as follows: non-polar, medium polarity and polar fraction, When submitted to the same indomethacin-induced ulcer in rats they resulted in different levels of inhibition of the ulcerative lesion index. The participation of nitric oxide was evaluated on an ethanol-induced ulcer model which had a previous administration of L-NAME, a NO-synthase inhibitor. Under these conditions, the medium polarity fraction maintained the antiulcerogenic activity, suggesting that nitric oxide could not be involved in the antiulcerogenic activity. When the animal groups were treated with N-ethylmaleimide, an alkylator of sulphhydryl groups, using the same experimental model, the medium polarity fraction maintained its antiulcerogenic activity, suggesting that the pharmacological mechanism is not related to non-protein sulphydryl compounds. On the ethanol-induced ulcer with previous indomethacin treatment, the medium polarity fraction lost its antiulcerogenic activity indicating that the active compounds of Artemisia annua L. increase the prostaglandin levels in the gastric mucosa. This hypothesis was reinforced by an increase of adherent mucus production by the gastric mucosa, produced by the medium polarity fraction on the hypothermic restraint stress induced ulcer model.

  19. Brain activation in response to randomized visual stimulation as obtained from conjunction and differential analysis: an fMRI study

    NASA Astrophysics Data System (ADS)

    Nasaruddin, N. H.; Yusoff, A. N.; Kaur, S.

    2014-11-01

    The objective of this multiple-subjects functional magnetic resonance imaging (fMRI) study was to identify the common brain areas that are activated when viewing black-and-white checkerboard pattern stimuli of various shapes, pattern and size and to investigate specific brain areas that are involved in processing static and moving visual stimuli. Sixteen participants viewed the moving (expanding ring, rotating wedge, flipping hour glass and bowtie and arc quadrant) and static (full checkerboard) stimuli during an fMRI scan. All stimuli have black-and-white checkerboard pattern. Statistical parametric mapping (SPM) was used in generating brain activation. Differential analyses were implemented to separately search for areas involved in processing static and moving stimuli. In general, the stimuli of various shapes, pattern and size activated multiple brain areas mostly in the left hemisphere. The activation in the right middle temporal gyrus (MTG) was found to be significantly higher in processing moving visual stimuli as compared to static stimulus. In contrast, the activation in the left calcarine sulcus and left lingual gyrus were significantly higher for static stimulus as compared to moving stimuli. Visual stimulation of various shapes, pattern and size used in this study indicated left lateralization of activation. The involvement of the right MTG in processing moving visual information was evident from differential analysis, while the left calcarine sulcus and left lingual gyrus are the areas that are involved in the processing of static visual stimulus.

  20. Mechanism of active transport: free energy dissipation and free energy transduction.

    PubMed Central

    Tanford, C

    1982-01-01

    The thermodynamic pathway for "chemiosmotic" free energy transduction in active transport is discussed with an ATP-driven Ca2+ pump as an illustrative example. Two innovations are made in the analysis. (i) Free energy dissipated as heat is rigorously excluded from overall free energy bookkeeping by focusing on the dynamic equilibrium state of the chemiosmotic process. (ii) Separate chemical potential terms for free energy donor and transported ions are used to keep track of the thermodynamic state of each substrate through the reaction cycle. These procedures clarify the mechanism of free energy transduction, even without step-by-step analysis. The results show that free energy exchange must occur in its entirety among protein-bound species. Imposition of conditions for an adequate rate of physiological function further indicates (i) that the standard free energy of hydrolysis of protein-bound ATP (to yield protein-bound products) needs to differ substantially from the standard free energy of hydrolysis in solution and (ii) that binding sites for the transported ions must have different affinities when facing opposite sides of the membrane. The results also demonstrate that step-by-step "basic" free energy changes (often used in the form of free energy level diagrams) are inherently unsuited for analysis of the mechanism of free energy transduction. PMID:6216483

  1. Physical Modeling of Activation Energy in Organic Semiconductor Devices based on Energy and Momentum Conservations.

    PubMed

    Mao, Ling-Feng; Ning, H; Hu, Changjun; Lu, Zhaolin; Wang, Gaofeng

    2016-04-22

    Field effect mobility in an organic device is determined by the activation energy. A new physical model of the activation energy is proposed by virtue of the energy and momentum conservation equations. The dependencies of the activation energy on the gate voltage and the drain voltage, which were observed in the experiments in the previous independent literature, can be well explained using the proposed model. Moreover, the expression in the proposed model, which has clear physical meanings in all parameters, can have the same mathematical form as the well-known Meyer-Neldel relation, which lacks of clear physical meanings in some of its parameters since it is a phenomenological model. Thus it not only describes a physical mechanism but also offers a possibility to design the next generation of high-performance optoelectronics and integrated flexible circuits by optimizing device physical parameter.

  2. Physical Modeling of Activation Energy in Organic Semiconductor Devices based on Energy and Momentum Conservations

    PubMed Central

    Mao, Ling-Feng; Ning, H.; Hu, Changjun; Lu, Zhaolin; Wang, Gaofeng

    2016-01-01

    Field effect mobility in an organic device is determined by the activation energy. A new physical model of the activation energy is proposed by virtue of the energy and momentum conservation equations. The dependencies of the activation energy on the gate voltage and the drain voltage, which were observed in the experiments in the previous independent literature, can be well explained using the proposed model. Moreover, the expression in the proposed model, which has clear physical meanings in all parameters, can have the same mathematical form as the well-known Meyer-Neldel relation, which lacks of clear physical meanings in some of its parameters since it is a phenomenological model. Thus it not only describes a physical mechanism but also offers a possibility to design the next generation of high-performance optoelectronics and integrated flexible circuits by optimizing device physical parameter. PMID:27103586

  3. Physical Modeling of Activation Energy in Organic Semiconductor Devices based on Energy and Momentum Conservations

    NASA Astrophysics Data System (ADS)

    Mao, Ling-Feng; Ning, H.; Hu, Changjun; Lu, Zhaolin; Wang, Gaofeng

    2016-04-01

    Field effect mobility in an organic device is determined by the activation energy. A new physical model of the activation energy is proposed by virtue of the energy and momentum conservation equations. The dependencies of the activation energy on the gate voltage and the drain voltage, which were observed in the experiments in the previous independent literature, can be well explained using the proposed model. Moreover, the expression in the proposed model, which has clear physical meanings in all parameters, can have the same mathematical form as the well-known Meyer-Neldel relation, which lacks of clear physical meanings in some of its parameters since it is a phenomenological model. Thus it not only describes a physical mechanism but also offers a possibility to design the next generation of high-performance optoelectronics and integrated flexible circuits by optimizing device physical parameter.

  4. Stress versus temperature dependence of activation energies for creep

    NASA Technical Reports Server (NTRS)

    Freed, A. D.; Raj, S. V.; Walker, K. P.

    1992-01-01

    The activation energy for creep at low stresses and elevated temperatures is associated with lattice diffusion, where the rate controlling mechanism for deformation is dislocation climb. At higher stresses and intermediate temperatures, the rate controlling mechanism changes from dislocation climb to obstacle-controlled dislocation glide. Along with this change in deformation mechanism occurs a change in the activation energy. When the rate controlling mechanism for deformation is obstacle-controlled dislocation glide, it is shown that a temperature-dependent Gibbs free energy does better than a stress-dependent Gibbs free energy in correlating steady-state creep data for both copper and LiF-22mol percent CaF2 hypereutectic salt.

  5. Stress versus temperature dependent activation energies in creep

    NASA Technical Reports Server (NTRS)

    Freed, A. D.; Raj, S. V.; Walker, K. P.

    1990-01-01

    The activation energy for creep at low stresses and elevated temperatures is lattice diffusion, where the rate controlling mechanism for deformation is dislocation climb. At higher stresses and intermediate temperatures, the rate controlling mechanism changes from that of dislocation climb to one of obstacle-controlled dislocation glide. Along with this change, there occurs a change in the activation energy. It is shown that a temperature-dependent Gibbs free energy does a good job of correlating steady-state creep data, while a stress-dependent Gibbs free energy does a less desirable job of correlating the same data. Applications are made to copper and a LiF-22 mol. percent CaF2 hypereutectic salt.

  6. Evaluation of Not-Activated and Activated PRP in Hair Loss Treatment: Role of Growth Factor and Cytokine Concentrations Obtained by Different Collection Systems

    PubMed Central

    Gentile, Pietro; Cole, John P.; Cole, Megan A.; Garcovich, Simone; Bielli, Alessandra; Scioli, Maria Giovanna; Orlandi, Augusto; Insalaco, Chiara; Cervelli, Valerio

    2017-01-01

    Platelet rich plasma (PRP) was tested as a potential therapy for androgenetic alopecia (AGA) through two different clinical protocols in which one population (18 participants) received half-head treatment with autologous non-activated PRP (A-PRP) produced by CPunT Preparation System (Biomed Device, Modena, Italy) and the other half-head with placebo, and a second separated population in which all participants (n = 6, 3 participants per group) received treatment with calcium-activated PRP (AA-PRP) produced from one of two different PRP collection devices (Regen Blood Cell Therapy or Arthrex Angel System). For the A-PRP study, three treatments were administered over 30-day intervals. Trichoscan analysis of patients, three months post-treatment, showed a clinical improvement in the number of hairs in the target area (36 ± 3 hairs) and in total hair density (65 ± 5 hair cm2), whereas negligible improvements in hair count (1.1 ± 1.4 hairs) and density (1.9 ± 10.2 hair cm2) were seen in the region of the scalp that received placebo. Microscopic evaluation conducted two weeks after treatment showed also an increase in epidermal thickness, Ki67+ keratinocytes, and in the number of follicles. The AA-PRP treatment groups received a singular set of injections, and six months after the treatments were administered, notable differences in clinical outcomes were obtained from the two PRP collection devices (+90 ± 6 hair cm2 versus −73 ± 30 hair cm2 hair densities, Regen versus Arthrex). Growth factor concentrations in AA-PRP prepared from the two collection devices did not differ significantly upon calcium activation. PMID:28216604

  7. Energy-aware activity classification using wearable sensor networks

    NASA Astrophysics Data System (ADS)

    Dong, Bo; Montoye, Alexander; Moore, Rebecca; Pfeiffer, Karin; Biswas, Subir

    2013-05-01

    This paper presents implementation details, system characterization, and the performance of a wearable sensor network that was designed for human activity analysis. Specific machine learning mechanisms are implemented for recognizing a target set of activities with both out-of-body and on-body processing arrangements. Impacts of energy consumption by the on-body sensors are analyzed in terms of activity detection accuracy for out-of-body processing. Impacts of limited processing abilities for the on-body scenario are also characterized in terms of detection accuracy, by varying the background processing load in the sensor units. Impacts of varying number of sensors in terms of activity classification accuracy are also evaluated. Through a rigorous systems study, it is shown that an efficient human activity analytics system can be designed and operated even under energy and processing constraints of tiny on-body wearable sensors.

  8. Energy-aware Activity Classification using Wearable Sensor Networks

    PubMed Central

    Dong, Bo; Montoye, Alexander; Moore, Rebecca; Pfeiffer, Karin; Biswas, Subir

    2014-01-01

    This paper presents implementation details, system characterization, and the performance of a wearable sensor network that was designed for human activity analysis. Specific machine learning mechanisms are implemented for recognizing a target set of activities with both out-of-body and on-body processing arrangements. Impacts of energy consumption by the on-body sensors are analyzed in terms of activity detection accuracy for out-of-body processing. Impacts of limited processing abilities for the on-body scenario are also characterized in terms of detection accuracy, by varying the background processing load in the sensor units. Impacts of varying number of sensors in terms of activity classification accuracy are also evaluated. Through a rigorous systems study, it is shown that an efficient human activity analytics system can be designed and operated even under energy and processing constraints of tiny on-body wearable sensors. PMID:25075266

  9. Cellular Links between Neuronal Activity and Energy Homeostasis

    PubMed Central

    Shetty, Pavan K.; Galeffi, Francesca; Turner, Dennis A.

    2012-01-01

    Neuronal activity, astrocytic responses to this activity, and energy homeostasis are linked together during baseline, conscious conditions, and short-term rapid activation (as occurs with sensory or motor function). Nervous system energy homeostasis also varies during long-term physiological conditions (i.e., development and aging) and with adaptation to pathological conditions, such as ischemia or low glucose. Neuronal activation requires increased metabolism (i.e., ATP generation) which leads initially to substrate depletion, induction of a variety of signals for enhanced astrocytic function, and increased local blood flow and substrate delivery. Energy generation (particularly in mitochondria) and use during ATP hydrolysis also lead to considerable heat generation. The local increases in blood flow noted following neuronal activation can both enhance local substrate delivery but also provides a heat sink to help cool the brain and removal of waste by-products. In this review we highlight the interactions between short-term neuronal activity and energy metabolism with an emphasis on signals and factors regulating astrocyte function and substrate supply. PMID:22470340

  10. Evaluation of antioxidant activities of bioactive compounds and various extracts obtained from saffron (Crocus sativus L.): a review.

    PubMed

    Rahaiee, Somayeh; Moini, Sohrab; Hashemi, Maryam; Shojaosadati, Seyed Abbas

    2015-04-01

    Saffron (Crocus sativus L. stigma), the most valuable medicinal food product, belongs to the Iridaceae family which has been widely used as a coloring and flavoring agent. These properties are basically related to its crocins, picrocrocin and safranal contents which have all demonstrated health promoting properties. The present review article highlights the phytochemical constituents (phenolic and flavonoid compounds, degraded carotenoid compounds crocins and crocetin) that are important in antioxidant activity of saffron extracts. However, the synergistic effect of all the bioactive components presence in saffron gave a significant antioxidant activity similar to vegetables rich in carotenoids. Our study provides an updated overview focused on the antioxidant activity of saffron related to its bioactive compounds to design the different functional products in food, medicine and cosmetic industries.

  11. Activation energy of thermal desorption of silicon oxide layers on silicon substrates

    NASA Astrophysics Data System (ADS)

    Enta, Yoshiharu; Osanai, Shodai; Ogasawara, Takahito

    2017-02-01

    Thermal desorption rates of silicon oxide layers, from 20 to 120 nm in thickness, on silicon substrates in vacuum have been accurately obtained from intervals between ring structures formed inside voids on the oxide layers. From the temperature dependence of the desorption rate, the activation energy and frequency factor of the desorption reaction have been derived as a function of the oxide thickness. The obtained values are compared with the previous studies, and as a result, the activation energy is found to be almost constant ( 4 eV) in a wide range of the oxide thickness. The frequency factor decreases as the inverse square of the oxide thickness. The decomposition kinetics of the oxide layer is also discussed from the obtained results.

  12. Data on energy-band-gap characteristics of composite nanoparticles obtained by modification of the amorphous potassium polytitanate in aqueous solutions of transition metal salts

    PubMed Central

    Zimnyakov, D.A.; Sevrugin, A.V.; Yuvchenko, S.A.; Fedorov, F.S.; Tretyachenko, E.V.; Vikulova, M.A.; Kovaleva, D.S.; Krugova, E.Y.; Gorokhovsky, A.V.

    2016-01-01

    Here we present the data on the energy-band-gap characteristics of composite nanoparticles produced by modification of the amorphous potassium polytitanate in aqueous solutions of different transition metal salts. Band gap characteristics are investigated using diffuse reflection spectra of the obtained powders. Calculated logarithmic derivative quantity of the Kubelka–Munk function reveals a presence of local maxima in the regions 0.5–1.5 eV and 1.6–3.0 eV which correspond to band gap values of the investigated materials. The values might be related to the constituents of the composite nanoparticles and intermediate products of their chemical interaction. PMID:27158654

  13. Studies on the formation of polymeric nano-emulsions obtained via low-energy emulsification and their use as templates for drug delivery nanoparticle dispersions.

    PubMed

    Calderó, G; Montes, R; Llinàs, M; García-Celma, M J; Porras, M; Solans, C

    2016-09-01

    Ethylcellulose nanoparticles have been obtained from O/W nano-emulsions of the water/polyoxyethylene 10 oleyl ether/[ethyl acetate+4wt% ethylcellulose] system by low energy-energy emulsification at 25°C. Nano-emulsions with droplet sizes below 200nm and high kinetic stability were chosen for solubilising dexamethasone (DXM). Phase behaviour, conductivity and optical analysis studies of the system have evidenced for the first time that both, the polymer and the drug play a role on the structure of the aggregates formed along the emulsification path. Nano-emulsion formation may take place by both, phase inversion and self-emulsification. Spherical polymeric nanoparticles containing surfactant, showing sizes below 160nm have been obtained from the nano-emulsions by organic solvent evaporation. DXM loading in the nanoparticles was high (>90%). The release kinetics of nanoparticle dispersions with similar particle size and encapsulated DXM but different polymer to surfactant ratio were studied and compared to an aqueous DXM solution. Drug release from the nanoparticle dispersions was slower than from the aqueous solution. While the DXM solution showed a Fickian release pattern, the release behaviour from the nanoparticle dispersions was faster than that expected from a pure Fickian release. A coupled diffusion/relaxation model fitted the results very well, suggesting that polymer chains undergo conformational changes enhancing drug release. The contribution of diffusion and relaxation to drug transport in the nanoparticle dispersions depended on their composition and release time. Surfactant micelles present in the nanoparticle dispersion may exert a mild reservoir effect. The small particle size and the prolonged DXM release provided by the ethylcellulose nanoparticle dispersions make them suitable vehicles for controlled drug delivery applications.

  14. In vitro study of the antifungal activity of essential oils obtained from Mentha spicata, Thymus vulgaris and Laurus nobilis.

    PubMed

    Houicher, Abderrahmane; Hechachna, Hind; Teldji, Hanifa; Ozogul, Fatih

    2016-09-27

    The aim of this study was to determine the antifungal activity of the essential oils isolated from three aromatic plants against 13 filamentous fungal strains. The major constituents of Mentha spicata, Thymus vulgaris, and Laurus nobilis essential oils were carvone (52.2%), linalool (78.1%), and 1,8-cineole (45.6%), respectively. M. spicata essential oil exhibited the strongest activity against all tested fungi in which Fusarium graminearum, F.moniliforme, and Penicillium expansum were the most sensitive to mint oil with lower minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) values of 2.5 μL mL-1 (v/v). T. vulgaris essential oil was less active compared to the oil of M. spicata. Aspergillus ochraceus was the most sensitive strain to thyme oil with MIC and MFC values of 2.5 and 5 μL mL-1, respectively. T. vulgaris essential oil also exhibited a moderate fungicidal effect against the tested fungi, except for A. niger (MFC >20 μL mL-1). L. nobilis essential oil showed a similar antifungal activity with thyme oil in which A. parasiticus was the most resistant strain to this oil (MFC >20 μL mL-1). Our findings suggested the use of these essential oils as alternatives to synthetic fungicides in order to prevent pre-and post-harvest infections and improve product safety.

  15. In vitro digestibility, crystallinity, rheological, thermal, particle size and morphological characteristics of pinole, a traditional energy food obtained from toasted ground maize.

    PubMed

    Carrera, Y; Utrilla-Coello, R; Bello-Pérez, A; Alvarez-Ramirez, J; Vernon-Carter, E J

    2015-06-05

    Flour obtained from toasted ground maize grains is widely consumed by different ethnic groups of Northern Mexico and Southwest USA as an energy source. In this work the in vitro digestibility, crystallinity, rheological, thermal, particle size distribution and morphological characteristics of toasted ground white and blue maize flours were studied. X-ray diffraction studies showed that the crystallinity content was reduced, but that the hydrolysis rate and the in vitro digestibility of starch were greatly improved by the toasting process. The relative amount of rapidly digestible starch showed an important increase at the expense of resistant starch content reduction. The thermal properties of white maize starch increased slightly, but those of the blue maize starch decreased slightly after toasting. Aqueous dispersions formed with 10% (w/w) flour were heated at 90°C for 5min to induce starch gelling, in order to resemble thin porridges. The dispersed gels exhibited higher elastic modulus (G') than loss modulus (G'') in the linear viscoelastic region, with blue maize dispersions displaying higher moduli magnitudes. At higher shear strain amplitudes, G' decreased but G'' first increased and then decreased (overshoot phenomenon). The effects of toasting on the structure and functionality of maize starch are explained on the basis of limited gelatinization of the granules. The results in this work provide insights for understanding the extensive use of pinole by impoverished ethnic groups, and more recently by high performance ultra-runners and athletes, as an energy food.

  16. Effects of Manisa propolis on telomerase activity in leukemia cells obtained from the bone marrow of leukemia patients.

    PubMed

    Cogulu, O; Biray, C; Gunduz, C; Karaca, E; Aksoylar, S; Sorkun, K; Salih, B; Ozkinay, F

    2009-11-01

    Propolis is a resinous material collected by honeybees and obtained from beehives that has anticancer effects by inducing apoptosis. The aim of this study is to investigate the effect of propolis on human telomerase reverse transcriptase (hTERT) in the leukemia cells obtained from leukemia patients. Four different bone marrow cell cultures from each of four leukemia cases were prepared. The 60 ng/ml, 30 ng/ml and 15 ng/ml working concentrations of propolis were administered to three cultures of each patient, while one culture contained only culture medium. hTERT mRNA expression levels of cells were detected at 24 h, 48 h and 72 h using the LightCycler 2.0 instrument. A significant decrease in hTERT expression levels was observed in the 60 ng/ml concentration of propolis. In conclusion, Manisa propolis may also have a potential effect on the expression of hTERT in leukemia-particularly owing to its constituent chrysin.

  17. Surface diffusion activation energy determination using ion beam microtexturing

    NASA Technical Reports Server (NTRS)

    Rossnagel, S. M.; Robinson, R. S.

    1982-01-01

    The activation energy for impurity atom (adatom) surface diffusion can be determined from the temperature dependence of the spacing of sputter cones. These cones are formed on the surface during sputtering while simultaneously adding impurities. The impurities form clusters by means of surface diffusion, and these clusters in turn initiate cone formation. Values are given for the surface diffusion activation energies for various materials on polycrystalline Cu, Al, Pb, Au, and Ni. The values for different impurity species on each of these substrates are approximately independent of impurity species within the experimental uncertainty, suggesting the absence of strong chemical bonding effects on the diffusion.

  18. United States Department of Energy Thermally Activated Heat Pump Program

    SciTech Connect

    Fiskum, R.J.; Adcock, P.W.; DeVault, R.C.

    1996-06-01

    The US Department of Energy (DOE) is working with partners from the gas heating and cooling industry to improve energy efficiency using advance absorption technologies, to eliminate chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), to reduce global warming through more efficient combustion of natural gas, and to impact electric peak demand of air conditioning. To assist industry in developing these gas heating and cooling absorption technologies, the US DOE sponsors the Thermally Activated Heat Pump Program. It is divided into five key activities, addressing residential gas absorption heat pumps, large commercial chillers, advanced absorption fluids, computer-aided design, and advanced ``Hi-Cool`` heat pumps.

  19. The aircraft energy efficiency active controls technology program

    NASA Technical Reports Server (NTRS)

    Hood, R. V., Jr.

    1977-01-01

    Broad outlines of the NASA Aircraft Energy Efficiency Program for expediting the application of active controls technology to civil transport aircraft are presented. Advances in propulsion and airframe technology to cut down on fuel consumption and fuel costs, a program for an energy-efficient transport, and integrated analysis and design technology in aerodynamics, structures, and active controls are envisaged. Fault-tolerant computer systems and fault-tolerant flight control system architectures are under study. Contracts with leading manufacturers for research and development work on wing-tip extensions and winglets for the B-747, a wing load alleviation system, elastic mode suppression, maneuver-load control, and gust alleviation are mentioned.

  20. Modelling the surface free energy parameters of polyurethane coats-part 1. Solvent-based coats obtained from linear polyurethane elastomers.

    PubMed

    Król, Piotr; Lechowicz, Jaromir B; Król, Bożena

    2013-04-01

    Polyurethane elastomers coating were synthesised by using typical diisocyanates, polyether and polyester polyols and HO-tertiary amines or diols as a chain extenders. Mole fractions of structural fragments (κexp) responsible for the polar interactions within polyurethane chains were calculated by (1)H NMR method. Obtained results were confronted with the analogous parameter values (κtheor) calculated on the basis of process stoichiometry, considering the stage of the production of isocyanate prepolymers and reaction of their extension for polyurethanes. Trials of linear correlation between the κexp parameters and surface free energy (SFE) values of investigated coatings were presented. SFE values were determined by Owens-Wendt method, using contact angles measured with the goniometric method. Based on achieved results, another empirical models, allowing for prediction the influence of the kind of polyurethane raw materials on SFE values of received coatings were determined. It was found that it is possible to regulate the SFE in the range millijoules per cubic metre by the selection of appropriate substrates. It has been found that use of 2,2,3,3-tetrafluoro-1,4-butanediol as a fluorinated extender of prepolymer chains is essential to obtain coatings with increased hydrophobicity, applied among others as biomaterials-next to diphenylmethane diisocyanate and polyoxyethylene glycol.

  1. Statistical Estimation of the Protein-Ligand Binding Free Energy Based On Direct Protein-Ligand Interaction Obtained by Molecular Dynamics Simulation

    PubMed Central

    Fukunishi, Yoshifumi; Nakamura, Haruki

    2012-01-01

    We have developed a method for estimating protein-ligand binding free energy (ΔG) based on the direct protein-ligand interaction obtained by a molecular dynamics simulation. Using this method, we estimated the ΔG value statistically by the average values of the van der Waals and electrostatic interactions between each amino acid of the target protein and the ligand molecule. In addition, we introduced fluctuations in the accessible surface area (ASA) and dihedral angles of the protein-ligand complex system as the entropy terms of the ΔG estimation. The present method included the fluctuation term of structural change of the protein and the effective dielectric constant. We applied this method to 34 protein-ligand complex structures. As a result, the correlation coefficient between the experimental and calculated ΔG values was 0.81, and the average error of ΔG was 1.2 kcal/mol with the use of the fixed parameters. These results were obtained from a 2 nsec molecular dynamics simulation. PMID:24281257

  2. Energy and Man's Environment Activity Guide: An Interdisciplinary Teacher's Guide to Energy and Environmental Activities, Section Three - Conversion of Energy.

    ERIC Educational Resources Information Center

    Jones, John, Ed.

    This publication presents the activities pertaining to the third goal of this activity guide series. The activities in this publication focus on understanding conservation processes, efficiencies, socioeconomic costs, and personal decision-making. These materials are appropriate for middle school and junior high school students. These activities,…

  3. Antioxidant activity measured in different solvent fractions obtained from Mentha spicata Linn.: an analysis by ABTS*+ decolorization assay.

    PubMed

    Arumugam, Ponnan; Ramamurthy, Perumal; Santhiya, Sathiyavedu Thyagarajan; Ramesh, Arabandi

    2006-01-01

    Antioxidant compounds are abundantly available in plants and play an important role in scavenging free radicals, thus providing protection to humans against oxidative DNA damage. Mentha spicata Linn., commonly called spearmint, belongs to the family lamiaceae. It was selected in the present study because Mentha extracts have antioxidant properties due to the presence of eugenol, caffeic acid, rosmarinic acid and alpha-tocopherol. Four solvent fractions (hexane, chloroform, ethyl acetate and water) of ethanolic extract of dried leaves powder of M. spicata were analyzed for total antioxidant activity (TAA) and relative antioxidant activity (RAA) and compared with standard antioxidants such as Quercetin, beta-carotene, L-ascorbic acid and glutathione using ABTS*+ decolorization assay (ABTS/Potassium persulphate). The antioxidant activity was assumed to be from the total phenolic content of the ethanolic extract. Total phenolics are found to be highest in ethyl acetate fraction (54 mg/g) and least in hexane fraction (13 mg/g) and more or less similar in water and chloroform fractions (30-32 mg/g). TAA is found to be less in hexane and chloroform fractions (<53% at 50 microg/ml) and highest in ethyl acetate (95% at 20 microg/ml) and water (84% at 30 microg/ml) fractions. The RAA of ethyl acetate fraction is 1.1 compared to quercetin (at 5 microM/ml), but greater when compared to beta-carotene (15 microM/ml), L-ascorbic acid (15 microM/ml) and glutathione (15 microM/ml). The RAAs with these antioxidants are in the range of 1.31 -1.6. The values of RAAs for water fraction also show similar trend and are in the range of 1.0-1.4. The antioxidant activities of the solvent factions are closely related to the content of total phenolics present in them.

  4. Gentian violet exhibits activity against biofilms formed by oral Candida isolates obtained from HIV-infected patients.

    PubMed

    Traboulsi, Rana S; Mukherjee, Pranab K; Chandra, Jyotsna; Salata, Robert A; Jurevic, Richard; Ghannoum, Mahmoud A

    2011-06-01

    The effect of gentian violet against Candida albicans and non-Candida albicans biofilms formed on polymethylmethacrylate strips was evaluated using a dry weight assay and confocal laser scanning microscopy. The ability of gentian violet to inhibit Candida albicans germination was also assessed. Gentian violet activity against Candida biofilms was demonstrated by a reduction in dry weight, disruption of biofilm architecture, and reduced biofilm thickness. Additionally, gentian violet inhibited Candida germination in a concentration-dependent manner.

  5. Antioxidant activity and total phenolic compounds of Dezful sesame cake extracts obtained by classical and ultrasound-assisted extraction methods

    PubMed Central

    Esmaeilzadeh Kenari, Reza; Mohsenzadeh, Fatereh; Amiri, Zeinab Raftani

    2014-01-01

    Sesame cake is a by-product of sesame oil industry. In this study, the effect of extraction methods (maceration and sonication) and solvents (ethanol, methanol, ethanol/water (50:50), methanol/water (50:50), and water) on the antioxidant properties of sesame cake extracts are evaluated to determine the most suitable extraction method for optimal use of this product. Total phenolic content is measured according to the Folin–Ciocalteu method and antioxidant activities of each extract are evaluated with the 2,2-diphenyl-1-picrylhydrazyl (DPPH), β-carotene bleaching, and ferric reducing/antioxidant power (FRAP) methods. The highest amount of total phenolic compounds is observed in ethanol-ultrasonic extract with the amount of 88.89 mg/g gallic acid equivalent. Methanol-ultrasonic extract with the amount of 88.475% indicates the highest activity in scavenging DPPH free radicals. In β-carotene-linoleic acid system, ethanol-ultrasonic extract indicates the highest inhibition percent of 45.64. In FRAP assay, ethanol/water (50:50)-maceration and ethanol/water (50:50)-ultrasonic extracts with the absorption of 1.132 and 1.0745 nm indicate the highest antioxidant activity. PMID:25473500

  6. Composition, In Vitro Antioxidant and Antimicrobial Activities of Essential Oil and Oleoresins Obtained from Black Cumin Seeds (Nigella sativa L.)

    PubMed Central

    Singh, Sunita; Das, S. S.; Singh, G.; Schuff, Carola; de Lampasona, Marina P.; Catalán, César A. N.

    2014-01-01

    Gas chromatography-mass spectrometry (GC-MS) analysis revealed the major components in black cumin essential oils which were thymoquinone (37.6%) followed by p-cymene (31.2%), α-thujene (5.6%), thymohydroquinone (3.4%), and longifolene (2.0%), whereas the oleoresins extracted in different solvents contain linoleic acid as a major component. The antioxidant activity of essential oil and oleoresins was evaluated against linseed oil system at 200 ppm concentration by peroxide value, thiobarbituric acid value, ferric thiocyanate, ferrous ion chelating activity, and 1,1-diphenyl-2-picrylhydrazyl radical scavenging methods. The essential oil and ethyl acetate oleoresin were found to be better than synthetic antioxidants. The total phenol contents (gallic acid equivalents, mg GAE per g) in black cumin essential oil, ethyl acetate, ethanol, and n-hexane oleoresins were calculated as 11.47 ± 0.05, 10.88 ± 0.9, 9.68 ± 0.06, and 8.33 ± 0.01, respectively, by Folin-Ciocalteau method. The essential oil showed up to 90% zone inhibition against Fusarium moniliforme in inverted petri plate method. Using agar well diffusion method for evaluating antibacterial activity, the essential oil was found to be highly effective against Gram-positive bacteria. PMID:24689064

  7. Structural Characterization and Antimicrobial Activity of a Biosurfactant Obtained From Bacillus pumilus DSVP18 Grown on Potato Peels

    PubMed Central

    Sharma, Deepak; Ansari, Mohammad Javed; Gupta, Sonam; Al Ghamdi, Ahmad; Pruthi, Parul; Pruthi, Vikas

    2015-01-01

    Background: Biosurfactants constitute a structurally diverse group of surface-active compounds derived from microorganisms. They are widely used industrially in various industrial applications such as pharmaceutical and environmental sectors. Major limiting factor in biosurfactant production is their production cost. Objectives: The aim of this study was to investigate biosurfactant production under laboratory conditions with potato peels as the sole source of carbon source. Materials and Methods: A biosurfactant-producing bacterial strain (Bacillus pumilus DSVP18, NCBI GenBank accession no. GQ865643) was isolated from motor oil contaminated soil samples. Biochemical characteristics of the purified biosurfactant were determined and its chemical structure was analyzed. Stability studies were performed and biological activity of the biosurfactant was also evaluated. Results: The strain, when grown on modified minimal salt media supplemented with 2% potato peels as the sole carbon source, showed the ability to reduce Surface Tension (ST) value of the medium from 72 to 28.7 mN/m. The isolated biosurfactant (3.2 ± 0.32 g/L) was stable over a wide range of temperatures (20 - 120 ºC), pH (2-12) and salt concentrations (2 - 12%). When characterized using high-performance liquid chromatography (HPLC) and Fourier transform infrared spectroscopy, it was found to be a lipopeptide in nature, which was further confirmed by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (mass peak 1044.60) and nuclear magnetic resonance (NMR) studies. Data showed that the isolated biosurfactant at the concentration range of 30 - 35 µg/ml had strong antimicrobial activity when tested against standard strains of Bacillus cereus, Escherichia coli, Salmonella enteritidis, Staphylococcus aureus and Paenibacillus larvae. Conclusions: Potato peels were proved to be potentially useful substrates for biosurfactant production by B. pumilus DSVP18. The strain possessed a

  8. Energy expenditure and habitual physical activities in adolescent sprint athletes.

    PubMed

    Aerenhouts, Dirk; Zinzen, Evert; Clarys, Peter

    2011-01-01

    This study aimed to assess total energy expenditure (TEE) and specific habitual physical activities in adolescent sprint athletes. Two methods used to estimate TEE, an activity diary (AD) and SenseWear armband (SWA), were compared. Sixteen athletes (6 girls, 10 boys, mean age 16.5 ± 1.6 yr) simultaneously wore a SWA and completed an AD and food diary during one week. Basal energy expenditure as given by the SWA when taken off was corrected for the appropriate MET value using the AD. TEE as estimated by the AD and SWA was comparable (3196 ± 590 kcal and 3012 ± 518 kcal, p = 0.113) without day-to-day variations in TEE and energy expended in activities of high intensity. Daily energy intake (2569 ± 508 kcal) did not match TEE according to both the AD and SWA (respectively p < 0.001 and p = 0.007). Athletes were in a supine position for a longer time on weekend days than on week days and slept longer on Sundays. Athletes reported a longer time of high-intensive physical activities in the AD than registered by the SWA on 4 out of 7 days. In addition to specific sprint activities on 3 to 7 days per week, 11 out of 16 athletes actively commuted to school where they participated in sports once or twice per week. The AD and the SWA are comparable in the estimation of TEE, which appears realistic and sustainable. The SWA offers an appropriate and objective method in the assessment of TEE, sleeping and resting in adolescent athletes on the condition that detailed information is given for the times the armband is not worn. The AD offers activity specific information but relies on the motivation, compliance and subjectivity of the individual, especially considering high-intensive intermittent training. Key pointsThe activity diary and Sensewear armband provide comparable estimates of TEE in adolescent sprint athletes.A high inter-individual variation was observed in time spent in high-intensity physical activities, advocating an individual based assessment when coaching

  9. Structural Aspects of Antioxidant and Genotoxic Activities of Two Flavonoids Obtained from Ethanolic Extract of Combretum leprosum

    PubMed Central

    Viau, Cassiana Macagnan; Moura, Dinara Jaqueline; Pflüger, Pricila; Facundo, Valdir Alves

    2016-01-01

    Combretum leprosum Mart., a member of the Combretaceae family, is a traditionally used Brazilian medicinal plant, although no evidence in the literature substantiates its antioxidant action and the safety of its use. We evaluated the antioxidant properties of the ethanolic extract (EE) from flowers of C. leprosum and its isolated products 5,3′-dihydroxy-3,7,4′-trimethoxyflavone (FCL2) and 5,3′,4′-trihydroxy-3,7-dimethoxyflavone (FCL5) in Saccharomyces cerevisiae strains proficient and deficient in antioxidant defenses. Their mutagenic activity was also assayed in S. cerevisiae, whereas cytotoxic and genotoxic properties were evaluated by MTT and Comet Assays, respectively, in V79 cells. We show that the EE, FCL2, and FCL5 have a significant protective effect against H2O2. FCL2 showed a better antioxidant action, which can be related to the activation of the 3′-OH in the presence of a methoxyl group at 4′ position in the B-ring of the molecule, while flavonoids did not induce mutagenesis in yeast, and the EE was mutagenic at high concentrations. The toxicity of these compounds in V79 cells increases from FCL2 = FCL5 < EE; although not cytotoxic, FCL5 induced an increase in DNA damage. The antioxidant effect, along with the lower toxicity and the absence of genotoxicity, suggests that FCL2 could be suitable for pharmacological use. PMID:27478483

  10. Energy and angular dependence of active-type personal dosemeter for high-energy neutron.

    PubMed

    Rito, Hirotaka; Yamauchi, Tomoya; Oda, Keiji

    2011-07-01

    In order to develop an active-type personal dosemeter having suitable sensitivity to high-energy neutrons, the characteristic response of silicon surface barrier detector has been investigated experimentally and theoretically. An agreement of the shape of pulse-height distribution, its change with radiator thickness and the relative sensitivity was confirmed between the calculated and experimental results for 14.8-MeV neutrons. The angular dependence was estimated for other neutron energies, and found that the angular dependence decreased with the incident energy. The reason was also discussed with regard to the radiator thickness relative to maximum range of recoil protons.

  11. Determining characteristics of melting cheese by activation energy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Activation energy of flow (Ea) between 30 and 44 deg C was measured from temperature sweeps of various cheeses to determine its usefulness in predicting rheological behavior upon heating. Seven cheese varieties were heated in a rheometer from 22 to 70 deg C, and Ea was calculated from the resulting ...

  12. Activation energy measurements in rheological analysis of cheese

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Activation energy of flow (Ea) was calculated from temperature sweeps of cheeses with contrasting characteristics to determine its usefulness in predicting rheological behavior upon heating. Cheddar, Colby, whole milk Mozzarella, low moisture part skim Mozzarella, Parmesan, soft goat, and Queso Fre...

  13. Solar Energy Education. Industrial arts: student activities. Field test edition

    SciTech Connect

    Not Available

    1981-02-01

    In this teaching manual several activities are presented to introduce students to information on solar energy through classroom instruction. Wind power is also included. Instructions for constructing demonstration models for passive solar systems, photovoltaic cells, solar collectors and water heaters, and a bicycle wheel wind turbine are provided. (BCS)

  14. Prediction of energy expenditure and physical activity in preschoolers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurate, nonintrusive, and feasible methods are needed to predict energy expenditure (EE) and physical activity (PA) levels in preschoolers. Herein, we validated cross-sectional time series (CSTS) and multivariate adaptive regression splines (MARS) models based on accelerometry and heart rate (HR) ...

  15. Energy expended by boys playing active video games.

    PubMed

    White, Kate; Schofield, Grant; Kilding, Andrew E

    2011-03-01

    The purpose of this study was to: (1) determine energy expenditure (EE) during a range of active video games (AVGs) and (2) determine whether EE during AVGs is influenced by gaming experience or fitness. Twenty-six boys (11.4±0.8 years) participated and performed a range of sedentary activities (resting, watching television and sedentary gaming), playing AVGs (Nintendo® Wii Bowling, Boxing, Tennis, and Wii Fit Skiing and Step), walking and running including a maximal fitness test. During all activities, oxygen uptake, heart rate and EE were determined. The AVGs resulted in a significantly higher EE compared to rest (63-190%, p≤0.001) and sedentary screen-time activities (56-184%, p≤0.001). No significant differences in EE were found between the most active video games and walking. There was no evidence to suggest that gaming experience or aerobic fitness influenced EE when playing AVGs. In conclusion, boys expended more energy during active gaming compared to sedentary activities. Whilst EE during AVG is game-specific, AVGs are not intense enough to contribute towards the 60min of daily moderate-to-vigorous physical activity that is currently recommended for children.

  16. Predicting Activity Energy Expenditure Using the Actical[R] Activity Monitor

    ERIC Educational Resources Information Center

    Heil, Daniel P.

    2006-01-01

    This study developed algorithms for predicting activity energy expenditure (AEE) in children (n = 24) and adults (n = 24) from the Actical[R] activity monitor. Each participant performed 10 activities (supine resting, three sitting, three house cleaning, and three locomotion) while wearing monitors on the ankle, hip, and wrist; AEE was computed…

  17. Decoding tactile afferent activity to obtain an estimate of instantaneous force and torque applied to the fingerpad.

    PubMed

    Khamis, Heba; Birznieks, Ingvars; Redmond, Stephen J

    2015-07-01

    Dexterous manipulation is not possible without sensory information about object properties and manipulative forces. Fundamental neuroscience has been unable to demonstrate how information about multiple stimulus parameters may be continuously extracted, concurrently, from a population of tactile afferents. This is the first study to demonstrate this, using spike trains recorded from tactile afferents innervating the monkey fingerpad. A multiple-regression model, requiring no a priori knowledge of stimulus-onset times or stimulus combination, was developed to obtain continuous estimates of instantaneous force and torque. The stimuli consisted of a normal-force ramp (to a plateau of 1.8, 2.2, or 2.5 N), on top of which -3.5, -2.0, 0, +2.0, or +3.5 mNm torque was applied about the normal to the skin surface. The model inputs were sliding windows of binned spike counts recorded from each afferent. Models were trained and tested by 15-fold cross-validation to estimate instantaneous normal force and torque over the entire stimulation period. With the use of the spike trains from 58 slow-adapting type I and 25 fast-adapting type I afferents, the instantaneous normal force and torque could be estimated with small error. This study demonstrated that instantaneous force and torque parameters could be reliably extracted from a small number of tactile afferent responses in a real-time fashion with stimulus combinations that the model had not been exposed to during training. Analysis of the model weights may reveal how interactions between stimulus parameters could be disentangled for complex population responses and could be used to test neurophysiologically relevant hypotheses about encoding mechanisms.

  18. Thermodynamic Derivation of the Activation Energy for Ice Nucleation

    NASA Technical Reports Server (NTRS)

    Barahona, D.

    2015-01-01

    Cirrus clouds play a key role in the radiative and hydrological balance of the upper troposphere. Their correct representation in atmospheric models requires an understanding of the microscopic processes leading to ice nucleation. A key parameter in the theoretical description of ice nucleation is the activation energy, which controls the flux of water molecules from the bulk of the liquid to the solid during the early stages of ice formation. In most studies it is estimated by direct association with the bulk properties of water, typically viscosity and self-diffusivity. As the environment in the ice-liquid interface may differ from that of the bulk, this approach may introduce bias in calculated nucleation rates. In this work a theoretical model is proposed to describe the transfer of water molecules across the ice-liquid interface. Within this framework the activation energy naturally emerges from the combination of the energy required to break hydrogen bonds in the liquid, i.e., the bulk diffusion process, and the work dissipated from the molecular rearrangement of water molecules within the ice-liquid interface. The new expression is introduced into a generalized form of classical nucleation theory. Even though no nucleation rate measurements are used to fit any of the parameters of the theory the predicted nucleation rate is in good agreement with experimental results, even at temperature as low as 190 K, where it tends to be underestimated by most models. It is shown that the activation energy has a strong dependency on temperature and a weak dependency on water activity. Such dependencies are masked by thermodynamic effects at temperatures typical of homogeneous freezing of cloud droplets; however, they may affect the formation of ice in haze aerosol particles. The new model provides an independent estimation of the activation energy and the homogeneous ice nucleation rate, and it may help to improve the interpretation of experimental results and the

  19. An assessment of cloud top thermodynamic phase products obtained from A-Train passive and active sensors

    NASA Astrophysics Data System (ADS)

    Zeng, S.; Riedi, J.; Parol, F.; Cornet, C.; Thieuleux, F.

    2013-09-01

    The A-Train observations provide an unprecedented opportunity for the production of high quality dataset describing cloud properties. We illustrate in this study the use of one year of coincident POLDER (Polarization and Directionality of the Earth Reflectance), MODIS (MODerate Resolution Imaging Spectroradiometer) and CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) observations to establish a reference dataset for the description of cloud top thermodynamic phase at global scale. We present the results of an extensive comparison between POLDER and MODIS cloud top phase products and discuss those in view of cloud vertical structure and optical properties derived simultaneously from collocated CALIOP active measurements. These results allow to identify and quantify potential biases present in the 3 considered dataset. Among those, we discuss the impacts of observation geometry, thin cirrus in multilayered and single layered cloud systems, supercooled liquid droplets, aerosols, fractional cloud cover and snow/ice or bright surfaces on global statistics of cloud phase derived from POLDER and MODIS passive measurements. Based on these analysis we define criteria for the selection of high confidence cloud phase retrievals which in turn can serve for the establishment of a reference cloud phase product. This high confidence joint product derived from POLDER/PARASOL and MODIS/Aqua can be used in the future as a benchmark for the evaluation of other cloud climatologies, for the assessment of cloud phase representation in models and the development of better cloud phase parametrization in the general circulation models (GCMs).

  20. Photo-inducible cytotoxic and clastogenic activities of 3,6-di-substituted acridines obtained by acylation of proflavine.

    PubMed

    Benchabane, Yohann; Di Giorgio, Carole; Boyer, Gérard; Sabatier, Anne-Sophie; Allegro, Diane; Peyrot, Vincent; De Méo, Michel

    2009-06-01

    The cytotoxicity and photo-enhanced cytotoxicity of a series of 18 3,6-di-substituted acridines were evaluated on both tumour CHO cells and human normal keratinocytes, and compared to their corresponding clastogenicity as assessed by the micronucleus assay. Compounds 2f tert-butyl N-[(6-tert-butoxycarbonylamino)acridin-3-yl]carbamate and 2d N-[6-(pivalamino)acridin-3-yl]pivalamide displayed a specific cytotoxicity on CHO cells. These results suggested that the two derivatives could be considered as interesting candidates for anticancer chemotherapy and hypothesized that the presence of 1,1-dimethylethyl substituents was responsible for a strong nonclastogenic cytotoxicity. Compounds 2b and 2c, on the contrary, displayed a strong clastogenicity. They indicated that the presence of nonbranched aliphatic chains on positions 3 and 6 of the acridine rings tended to induce a significant clastogenic effect. Finally, they established that most of the acridine compounds could be photo-activated by UVA-visible rays and focussed on the significant role of light irradiation on their biological properties.

  1. Neutron energy spectra unfolding from foil activation detector measurements with MINUIT

    NASA Astrophysics Data System (ADS)

    Seghour, A.; Seghour, F. Z.

    2005-12-01

    A method for unfolding neutron energy spectra from foil activation measurements using the multiparameter function minimisation routine MINUIT of Cernlib has been developed. It is based on the expansion of the neutron energy distribution on a set of parameters that are fitted to minimise the square sum of differences between the measured and calculated activities under smoothness and shape constraints. A modified square sum of differences expression weighted by each activation detector response contribution over the whole neutron energy range is proposed and compared with the classical square sum formulation. The proposed unfolding procedure is first illustrated by a set of 15 detectors to simulate reaction rates calculated using a typical neutron reactor energy spectrum. The demonstration of the proposed method is next achieved using measured reaction rates of the Arkansas Nuclear One power plant (ANO) benchmark spectrum of the Neutron Metrology File (NMF-90). Results of the proposed method were compared with those obtained by STAYNL and MSANDB unfolding codes using the same input data and were found in good agreement with the measured activities. The developed procedure is found to have an interesting advantage in unfolding neutron energy distribution in cases of a lack of information on the a priori solution. This has been illustrated by unfolding the JOYO MK-II fast breeder reactor neutron spectrum, using a set of experimental activation rates without a guess solution.

  2. STAT3 Activities and Energy Metabolism: Dangerous Liaisons

    PubMed Central

    Camporeale, Annalisa; Demaria, Marco; Monteleone, Emanuele; Giorgi, Carlotta; Wieckowski, Mariusz R.; Pinton, Paolo; Poli, Valeria

    2014-01-01

    STAT3 mediates cytokine and growth factor receptor signalling, becoming transcriptionally active upon tyrosine 705 phosphorylation (Y-P). Constitutively Y-P STAT3 is observed in many tumors that become addicted to its activity, and STAT3 transcriptional activation is required for tumor transformation downstream of several oncogenes. We have recently demonstrated that constitutively active STAT3 drives a metabolic switch towards aerobic glycolysis through the transcriptional induction of Hif-1α and the down-regulation of mitochondrial activity, in both MEF cells expressing constitutively active STAT3 (Stat3C/C) and STAT3-addicted tumor cells. This novel metabolic function is likely involved in mediating pre-oncogenic features in the primary Stat3C/C MEFs such as resistance to apoptosis and senescence and rapid proliferation. Moreover, it strongly contributes to the ability of primary Stat3C/C MEFs to undergo malignant transformation upon spontaneous immortalization, a feature that may explain the well known causative link between STAT3 constitutive activity and tumor transformation under chronic inflammatory conditions. Taken together with the recently uncovered role of STAT3 in regulating energy metabolism from within the mitochondrion when phosphorylated on Ser 727, these data place STAT3 at the center of a hub regulating energy metabolism under different conditions, in most cases promoting cell survival, proliferation and malignant transformation even though with distinct mechanisms. PMID:25089666

  3. AHEAD: Integrated Activities in the High Energy Astrophysics Domain

    NASA Astrophysics Data System (ADS)

    Piro, Luigi; Natalucci, Lorenzo; Ahead Consortium

    2015-09-01

    AHEAD (Integrated Activities in the High Energy Astrophysics Domain) is a forthcoming project approved in the framework of the European Horizon 2020 program (Research Infrastructures for High Energy Astrophysics). The overall objective of AHEAD is to integrate national efforts in high-energy Astrophysics and to promote the domain at the European level, to keep its community at the cutting edge of science and technology and ensure that space observatories for high-energy astrophysics, with particular regard to Athena, are at the state of the art. AHEAD will integrate key research infrastructures for on-ground test and calibration of space-based sensors and electronics and promote their coordinated use. In parallel, the best facilities for data analysis of high-energy astrophysical observatories will be made available to the European community. The technological development will focus on the improvement of selected critical technologies, background modeling, cross calibration, and feasibility studies of space-based instrumentation for the benefit of future high energy missions like Athena, and the best exploitation of existing observatories. AHEAD will support the community via grants for collaborative studies, dissemination of results, and promotion of workshops. A strong public outreach package will ensure that the domain is well publicized at national, European and International level. Networking, joint research activities and access to infrastructures as devised in AHEAD, will serve to establish strong connections between institutes and industry to create the basis for a more rapid advancement of high-energy astrophysical science, space oriented instrumentation and cutting-edge sensor technology in Europe. This enables the development of new technologies and the associated growth of the European technology market with a dedicated technology innovation package, as well as the creation of a new generation of researchers.

  4. High-energy neutrinos from active galactic nuclei

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.; Done, C.; Salamon, M. H.; Sommers, P.

    1991-01-01

    The spectrum and high-energy neutrino background flux from photomeson production in active galactic nuclei (AGN) is calculated using the recent UV and X-ray observations to define the photon fields and an accretion-disk shock-acceleration model for producing high-energy particles. Collectively, AGN produce the dominant isotropic neutrino background between 10,000 and 10 to the 10th GeV, detectable with current instruments. AGN neutrinos should produce a sphere of stellar disruption which may explain the 'broad-line region' seen in AGN.

  5. Accuracies of the synthesized monochromatic CT numbers and effective atomic numbers obtained with a rapid kVp switching dual energy CT scanner

    SciTech Connect

    Goodsitt, Mitchell M.; Christodoulou, Emmanuel G.; Larson, Sandra C.

    2011-04-15

    Purpose: This study was performed to investigate the accuracies of the synthesized monochromatic images and effective atomic number maps obtained with the new GE Discovery CT750 HD CT scanner. Methods: A Gammex-RMI model 467 tissue characterization phantom and the CT number linearity section of a Phantom Laboratory Catphan 600 phantom were scanned using the dual energy (DE) feature on the GE CT750 HD scanner. Synthesized monochromatic images at various energies between 40 and 120 keV and effective atomic number (Z{sub eff}) maps were generated. Regions of interest were placed within these images/maps to measure the average monochromatic CT numbers and average Z{sub eff} of the materials within these phantoms. The true Z{sub eff} values were either supplied by the phantom manufacturer or computed using Mayneord's equation. The linear attenuation coefficients for the true CT numbers were computed using the NIST XCOM program with the input of manufacturer supplied elemental compositions and densities. The effects of small variations in the assumed true densities of the materials were also investigated. Finally, the effect of body size on the accuracies of the synthesized monochromatic CT numbers was investigated using a custom lumbar section phantom with and without an external fat-mimicking ring. Results: Other than the Z{sub eff} of the simulated lung inserts in the tissue characterization phantom, which could not be measured by DECT, the Z{sub eff} values of all of the other materials in the tissue characterization and Catphan phantoms were accurate to 15%. The accuracies of the synthesized monochromatic CT numbers of the materials in both phantoms varied with energy and material. For the 40-120 keV range, RMS errors between the measured and true CT numbers in the Catphan are 8-25 HU when the true CT numbers were computed using the nominal plastic densities. These RMS errors improve to 3-12 HU for assumed true densities within the nominal density {+-}0.02 g

  6. A fluorescence resonance energy transfer activation sensor for Arf6.

    PubMed

    Hall, Brian; McLean, Mark A; Davis, Kathryn; Casanova, James E; Sligar, Steven G; Schwartz, Martin A

    2008-03-15

    The involvement of the small GTPase Arf6 in Rac activation, cell migration, and cancer invasiveness suggests that it is activated in a spatially and temporally regulated manner. Small GTPase activation has been imaged in cells using probes in which the GTPase and a fragment of a downstream effector protein are fused to fluorescent reporter proteins that constitute a fluorescence resonance energy transfer (FRET) donor/acceptor pair. Unlike other Ras family GTPases, the N terminus of Arf6 is critical for membrane targeting and, thus, cannot be modified by fusion to a fluorescent protein. We found that the previously described C-terminal green fluorescent protein (GFP) derivative also shows diminished membrane targeting. Therefore, we inserted a fluorescent protein into an inert loop within the Arf6 sequence. This fusion showed normal membrane targeting, nucleotide-dependent interaction with the downstream effector GGA3, and normal regulation by a GTPase-activating protein (GAP) and a guanine nucleotide exchange factor (GEF). Using the recently developed CyPET/YPET fluorescent proteins as a FRET pair, we found that Arf6-CyPET underwent efficient energy transfer when bound to YPET-GGA3 effector domain in intact cells. The addition of platelet-derived growth factor (PDGF) to fibroblasts triggered a rapid and transient increase in FRET, indicative of Arf6 activation. These reagents should be useful for investigations of Arf6 activation and function.

  7. Diurnal Patterns of Physical Activity in Relation to Activity Induced Energy Expenditure in 52 to 83 Years-Old Adults

    PubMed Central

    Bonomi, Alberto G.; Westerterp, Klaas R.

    2016-01-01

    Background Ageing is associated with a declining physical activity level (PAL) and changes in the diurnal activity pattern. Changes in the activity pattern might help explaining the age-associated reduction of physical activity. Objective The aims were to investigate diurnal activity patterns within groups of older adults classified by PAL, to investigate diurnal activity patterns within age-groups and to investigate the association between the drop in activity and aerobic fitness. Methods Thirty-one healthy subjects aged between 52 and 83y were recruited for the study. Subjects were divided in sedentary (PAL<1.75), moderately active (1.75active (1.90energy expenditure measurements obtained with the doubly labelled water technique. Diurnal activity patterns were based on activity counts from an accelerometer during wake time and then divided in four quarters of equal time length. Additionally, aerobic fitness was measured as maximal oxygen uptake. Results Subjects had a PAL between 1.43 and 2.34 and an aerobic fitness between 18 and 49 ml/kg/min. Overall, activity patterns showed a peak in the first quarter of wake time (around 10AM) followed by a gradual decline of, on average, 5% per hour. Active subjects reached their peak in the first quarter and remained active until after the third quarter (11% drop each quarter on average). Moderately active and sedentary subjects reached their peak during the second quarter with a decrease during the third quarter (respectively 29% and 17% drop each quarter on average). The drop in physical activity between the first and the second half of the wake time was negatively associated with aerobic fitness (r = -0.39, p<0.05). Conclusion Active older adults maintained a larger amount of body movement for longer during their wake time. Diurnal physical activity declined more in adults ≥66 years old with lower aerobic fitness. PMID:27936145

  8. Surface orientation dependence of the activation energy of S diffusion in bcc Fe

    NASA Astrophysics Data System (ADS)

    Barnard, P. E.; Terblans, J. J.; Swart, H. C.

    2015-11-01

    The formation of vacancies in the low-index orientations of bcc Fe was studied by a combined computational modelling and experimental investigation by making use of density functional theory (DFT), Auger electron spectroscopy (AES), time-of-flight secondary ion mass spectrometry (TOF-SIMS) and X-ray diffraction (XRD). Vacancies were considered to occur as a result of a Schottky defect forming in the bcc Fe lattice. This predicted a surface orientation dependence on the vacancy formation energy and consequently also on the activation energy of diffusion. Activation energies for the segregation of S in the Fe(1 0 0), Fe(1 1 0) and Fe(1 1 1) surface orientations were calculated by DFT modelling as 2.75 eV, 2.86 eV and 1.94 eV respectively. Simulations furthermore revealed a variation in the segregation kinetics of S as a result of the activation energy dependence on the surface orientation. Experimental data obtained by AES, TOF-SIMS and XRD confirmed this variation in the segregation kinetics of S segregation in different Fe orientations. This article provides compelling evidence for the formation of vacancies in bcc Fe to occur via the Schottky defect mechanism, which results in the orientation dependence for the activation energy of diffusion.

  9. Directed transport of active particles over asymmetric energy barriers.

    PubMed

    Koumakis, N; Maggi, C; Di Leonardo, R

    2014-08-21

    We theoretically and numerically investigate the transport of active colloids to target regions, delimited by asymmetric energy barriers. We show that it is possible to introduce a generalized effective temperature that is related to the local variance of particle velocities. The stationary probability distributions can be derived from a simple diffusion equation in the presence of an inhomogeneous effective temperature resulting from the action of external force fields. In particular, transition rates over asymmetric energy barriers can be unbalanced by having different effective temperatures over the two slopes of the barrier. By varying the type of active noise, we find that equal values of diffusivity and persistence time may produce strongly varied effective temperatures and thus stationary distributions.

  10. The energy balance and pressure in the solar transition zone for network and active region features

    NASA Technical Reports Server (NTRS)

    Nicolas, K. R.; Bartoe, J.-D. F.; Brueckner, G. E.; Vanhoosier, M. E.

    1979-01-01

    The electron pressure and energy balance in the solar transition zone are determined for about 125 network and active region features on the basis of high spectral and spatial resolution extreme ultraviolet spectra. Si III line intensity ratios obtained from the Naval Research Laboratory high-resolution telescope and spectrograph during a rocket flight are used as diagnostics of electron density and pressure for solar features near 3.5 x 10 to the 4th K. Observed ratios are compared with the calculated dependence of the 1301 A/1312 A and 1301 A/1296 A line intensity ratios on electron density, temperature and pressure. Electron densities ranging from 2 x 10 to the 10th/cu cm to 10 to the 12th/cu cm and active region pressures from 3 x 10 to the 15th to 10 to the 16th/cu cm K are obtained. Energy balance calculations reveal the balance of the divergence of the conductive flux and turbulent energy dissipation by radiative energy losses in a plane-parallel homogeneous transition zone (fill factor of 1), and an energy source requirement for a cylindrical zone geometry (fill factor less than 0.04).

  11. Raman active high energy excitations in URu2Si2

    NASA Astrophysics Data System (ADS)

    Buhot, Jonathan; Gallais, Yann; Cazayous, Maximilien; Sacuto, Alain; Piekarz, Przemysław; Lapertot, Gérard; Aoki, Dai; Méasson, Marie-Aude

    2017-02-01

    We have performed Raman scattering measurements on URu2Si2 single crystals on a large energy range up to ∼1300 cm-1 and in all the Raman active symmetries as a function of temperature down to 15 K. A large excitation, active only in the Eg symmetry, is reported. It has been assigned to a crystal electric field excitation on the Uranium site. We discuss how this constrains the crystal electric field scheme of the Uranium ions. Furthermore, three excitations in the A1g symmetry are observed. They have been associated to double Raman phonon processes consistently with ab initio calculations of the phonons dispersion.

  12. Active Noise Control Experiments using Sound Energy Flu

    NASA Astrophysics Data System (ADS)

    Krause, Uli

    2015-03-01

    This paper reports on the latest results concerning the active noise control approach using net flow of acoustic energy. The test set-up consists of two loudspeakers simulating the engine noise and two smaller loudspeakers which belong to the active noise system. The system is completed by two acceleration sensors and one microphone per loudspeaker. The microphones are located in the near sound field of the loudspeakers. The control algorithm including the update equation of the feed-forward controller is introduced. Numerical simulations are performed with a comparison to a state of the art method minimising the radiated sound power. The proposed approach is experimentally validated.

  13. High-energy radiation from active galactic nuclei

    NASA Technical Reports Server (NTRS)

    Sikora, Marek

    1994-01-01

    Two recent findings concerning high-energy radiation properties of active galactic nuclei -- discovery of breaks in hard X-ray spectra of Seyfert galaxies, and discovery of huge fluxes of hard gamma rays from blazars -- seem to press us to change our standard views about radiation production in these objects. I review briefly the existing radiation models, confront them with the newest observations, and discuss newly emerging theoretical pictures which attempt to account for the discoveries.

  14. Heat and Mass Transfer in Unsteady Rotating Fluid Flow with Binary Chemical Reaction and Activation Energy

    PubMed Central

    Awad, Faiz G.; Motsa, Sandile; Khumalo, Melusi

    2014-01-01

    In this study, the Spectral Relaxation Method (SRM) is used to solve the coupled highly nonlinear system of partial differential equations due to an unsteady flow over a stretching surface in an incompressible rotating viscous fluid in presence of binary chemical reaction and Arrhenius activation energy. The velocity, temperature and concentration distributions as well as the skin-friction, heat and mass transfer coefficients have been obtained and discussed for various physical parametric values. The numerical results obtained by (SRM) are then presented graphically and discussed to highlight the physical implications of the simulations. PMID:25250830

  15. ZnO nanoparticles obtained by pulsed laser ablation and their composite with cotton fabric: Preparation and study of antibacterial activity

    NASA Astrophysics Data System (ADS)

    Svetlichnyi, Valery; Shabalina, Anastasiia; Lapin, Ivan; Goncharova, Daria; Nemoykina, Anna

    2016-05-01

    A simple deposition method was used to prepare a ZnO/cotton fabric composite from water and ethanol dispersions of ZnO nanoparticles obtained by the pulsed laser ablation method. The structure and composition of the nanoparticles from dispersions and as-prepared composites were studied using electron microscopy, X-ray diffraction, and spectroscopy. The nanoparticles and composite obtained exhibited antibacterial activity to three different pathogenic microorganisms-Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. An attempt to understand a mechanism of bactericidal effect of ZnO nanoparticles was made. It was shown that zinc ions and hydrogen peroxide were not responsible for antibacterial activity of the particles and the composite, and surface properties of nanoparticles played an important role in antibacterial activity of zinc oxide. The proposed composite is a promising material for use as an antibacterial bandage.

  16. Energy storage on ultrahigh surface area activated carbon fibers derived from PMIA.

    PubMed

    Castro-Muñiz, Alberto; Suárez-García, Fabián; Martínez-Alonso, Amelia; Tascón, Juan M D; Kyotani, Takashi

    2013-08-01

    High-performance carbon materials for energy storage applications have been obtained by using poly(m-phenylene isophthalamide), PMIA, as a precursor through the chemical activation of the carbonized aramid fiber by using KOH. The yield of the process of activation was remarkably high (25-40 wt%), resulting in activated carbon fibers (ACFs) with ultrahigh surface areas, over 3000 m(2) g(-1) , and pore volumes exceeding 1.50 cm(3) g(-1) , keeping intact the fibrous morphology. The porous structure and the surface chemical properties could easily be controlled through the conditions of activation. The PMIA-derived ACFs were tested in two types of energy storage applications. At -196 °C and 1 bar, H2 uptake values of approximately 3 t% were obtained, which, in combination with the textural properties, rendered it a good candidate for H2 adsorption at high pressure and temperature. The performance of the ACFs as electrodes for electrochemical supercapacitors was also investigated. Specific capacitance values between 297 and 531 g(-1) at 50 mA g(-1) were obtained in aqueous electrolyte (1 H2 SO4 ), showing different behaviors depending on the surface chemical properties.

  17. Antigenic fractions from Taenia crassiceps metacestodes obtained by hydrophobicity for the immunodiagnosis of active and inactive forms of neurocysticercosis in human cerebrospinal fluid samples.

    PubMed

    da Silva, Gabriela B; Nunes, Daniela S; de Sousa, José Eduardo N; Gonçalves-Pires, Maria do R F; Levenhagen, Marcelo A; Costa-Cruz, Julia M

    2017-04-01

    This study aimed to evaluate the total extract of Taenia crassiceps metacestodes (TC) and its antigenic fractions obtained by Triton X-114 fractionation techniques, such as detergent (DC) and aqueous (AC), in the immunodiagnosis of human neurocysticercosis (NCC). Cerebrospinal fluid samples were divided into two groups: Group 1 (n=40), which was further divided into active (n=20) and inactive (n=20) NCC, and Group 2 (control group), which comprised 39 CSF samples from patients who had another neurological disorder, were suffering from other infectious diseases of the brain or had other parasitic infections. The total extracts and antigenic fractions were tested by enzyme-linked immunosorbent assay (ELISA) to detect human IgG anti-Taenia solium. T. crassiceps fractions (DC and AC) showed the same value of sensitivity (Se), 100%, for active and inactive NCC and a specificity (Sp) of 97.4%. The DS fraction obtained from T. solium showed 100% Se for active NCC, 95% Se for inactive NCC and a 92.3% Sp. The AS fraction obtained from T. solium showed 100% Se for both active and inactive NCC and a 94.9% Sp. There was a positive correlation between the total saline extract of T. crassiceps (TC) and T. solium (TS) and their fractions (DC, AC, DS and AS). Positive predictive value, negative predictive value, diagnostic efficiency and Youden index were calculated. In conclusion, these results demonstrated that detergent and aqueous fractions obtained from T. crassiceps metacestodes are important sources of specific antigens and are efficient for immunodiagnosis of active and inactive NCC.

  18. Physical activity and physical activity induced energy expenditure in humans: measurement, determinants, and effects.

    PubMed

    Westerterp, Klaas R

    2013-01-01

    Physical activity is defined as any bodily movement produced by skeletal muscles that results in energy expenditure. The doubly labeled water method for the measurement of total energy expenditure (TEE), in combination with resting energy expenditure, is the reference for physical activity under free-living conditions. To compare the physical activity level (PAL) within and between species, TEE is divided by resting energy expenditure resulting in a figure without dimension. The PAL for sustainable lifestyles ranges between a minimum of 1.1-1.2 and a maximum of 2.0-2.5. The average PAL increases from 1.4 at age 1 year to 1.7-1.8 at reproductive age and declines again to 1.4 at age 90 year. Exercise training increases PAL in young adults when energy balance is maintained by increasing energy intake. Professional endurance athletes can reach PAL values around 4.0. Most of the variation in PAL between subjects can be ascribed to predisposition. A higher weight implicates higher movement costs and less body movement but not necessarily a lower PAL. Changes in physical activity primarily affect body composition and to a lesser extent body weight. Modern man has a similar PAL as a wild mammal of a similar body size.

  19. Energy management and control of active distribution systems

    NASA Astrophysics Data System (ADS)

    Shariatzadeh, Farshid

    Advancements in the communication, control, computation and information technologies have driven the transition to the next generation active power distribution systems. Novel control techniques and management strategies are required to achieve the efficient, economic and reliable grid. The focus of this work is energy management and control of active distribution systems (ADS) with integrated renewable energy sources (RESs) and demand response (DR). Here, ADS mean automated distribution system with remotely operated controllers and distributed energy resources (DERs). DER as active part of the next generation future distribution system includes: distributed generations (DGs), RESs, energy storage system (ESS), plug-in hybrid electric vehicles (PHEV) and DR. Integration of DR and RESs into ADS is critical to realize the vision of sustainability. The objective of this dissertation is the development of management architecture to control and operate ADS in the presence of DR and RES. One of the most challenging issues for operating ADS is the inherent uncertainty of DR and RES as well as conflicting objective of DER and electric utilities. ADS can consist of different layers such as system layer and building layer and coordination between these layers is essential. In order to address these challenges, multi-layer energy management and control architecture is proposed with robust algorithms in this work. First layer of proposed multi-layer architecture have been implemented at the system layer. Developed AC optimal power flow (AC-OPF) generates fair price for all DR and non-DR loads which is used as a control signal for second layer. Second layer controls DR load at buildings using a developed look-ahead robust controller. Load aggregator collects information from all buildings and send aggregated load to the system optimizer. Due to the different time scale at these two management layers, time coordination scheme is developed. Robust and deterministic controllers

  20. A strategy for obtaining both resting and psychologically activated state metabolic data from a single PET study using (F-18)-fluorodeoxyglucose(FDG)

    SciTech Connect

    Chang, J.; Duara, R.; Barker, W.; Apicella, A.; Gilson, A.

    1985-05-01

    When psychological activation is studied with PET using the deoxyglucose method, a stable and specific psychological state for at least 30 minutes is required before commencing the scan. At this time, if the subject reverts to the testing state, a progressive degradation of the activated pattern occurs. However, a strategy could be used to obtain corrected activation state data and resting state data in a single study using a tracer such as FDG. The amount of tracer FDG and FDG-6P in the tissue at the time of study completion, t, will be the sum of the remaining quantity (R) of tracer accumulated in the tissue at the time T, when activation ceases, and the uptake during the subsequent period t-T when resting state glucose transport kinetics apply.

  1. DOD-DOE Workshop on Joint Energy Activities

    SciTech Connect

    1980-01-01

    The general conditions for DOD-DOE interactions were delineated in an October 1978, Memorandum of Understanding (MOU) that identified two basic goals: improving energy efficiency and availability within DOD, and utilizing DOD and DOE expertise and facilities to carry out projects of mutual interest. There has been considerable interaction between DOD and DOE, including a number of proposed joint initiatives but a systematic and coordinated approach for nurturing, maintaining, and expanding these relationships has not been developed. A DOD-DOE Workshop on Joint Energy Activities was held on March 10-12, 1980. The workshop was structured into five working groups - Mobility Fuels, Conservation, Fossil Fuels for Fixed Facilities, Solar and Renewable Energy Sources, and Special Projects - with DOD and DOE cochairmen for each. Over a hundred DOD and DOE management, program, and policymaking representatives were brought together by the workshop Steering Committee to identify specific programs for inclusion in an overall plan for implementing the MOU and to deal with fundamental issues and problems of maintaining future communications. The workshop accomplished its goals, these being to: (1) improve communication among the appropriate key DOD and DOE personnel at all levels and promote information exchange; (2) review ongoing and already-proposed joint DOD and DOE programs; (3) initiate a coordinated, systematic effort to establish joint DOD-DOE energy-security programs; and (4) propose specific programs and projects of mutual interest for inclusion in a follow-on joint-implementation plan.

  2. Ultra-high-energy cosmic rays from low-luminosity active galactic nuclei

    NASA Astrophysics Data System (ADS)

    Duţan, Ioana; Caramete, Laurenţiu I.

    2015-03-01

    We investigate the production of ultra-high-energy cosmic ray (UHECR) in relativistic jets from low-luminosity active galactic nuclei (LLAGN). We start by proposing a model for the UHECR contribution from the black holes (BHs) in LLAGN, which present a jet power Pj ⩽1046 erg s-1. This is in contrast to the opinion that only high-luminosity AGN can accelerate particles to energies ⩾ 50 EeV. We rewrite the equations which describe the synchrotron self-absorbed emission of a non-thermal particle distribution to obtain the observed radio flux density from sources with a flat-spectrum core and its relationship to the jet power. We found that the UHECR flux is dependent on the observed radio flux density, the distance to the AGN, and the BH mass, where the particle acceleration regions can be sustained by the magnetic energy extraction from the BH at the center of the AGN. We use a complete sample of 29 radio sources with a total flux density at 5 GHz greater than 0.5 Jy to make predictions for the maximum particle energy, luminosity, and flux of the UHECRs from nearby AGN. These predictions are then used in a semi-analytical code developed in Mathematica (SAM code) as inputs for the Monte-Carlo simulations to obtain the distribution of the arrival direction at the Earth and the energy spectrum of the UHECRs, taking into account their deflection in the intergalactic magnetic fields. For comparison, we also use the CRPropa code with the same initial conditions as for the SAM code. Importantly, to calculate the energy spectrum we also include the weighting of the UHECR flux per each UHECR source. Next, we compare the energy spectrum of the UHECRs with that obtained by the Pierre Auger Observatory.

  3. Estimating the Gibbs energy of hydration from molecular dynamics trajectories obtained by integral equations of the theory of liquids in the RISM approximation

    NASA Astrophysics Data System (ADS)

    Tikhonov, D. A.; Sobolev, E. V.

    2011-04-01

    A method of integral equations of the theory of liquids in the reference interaction site model (RISM) approximation is used to estimate the Gibbs energy averaged over equilibrium trajectories computed by molecular mechanics. Peptide oxytocin is selected as the object of interest. The Gibbs energy is calculated using all chemical potential formulas introduced in the RISM approach for the excess chemical potential of solvation and is compared with estimates by the generalized Born model. Some formulas are shown to give the wrong sign of Gibbs energy changes when peptide passes from the gas phase into water environment; the other formulas give overestimated Gibbs energy changes with the right sign. Note that allowance for the repulsive correction in the approximate analytical expressions for the Gibbs energy derived by thermodynamic perturbation theory is not a remedy.

  4. Kinetic study of solid waste pyrolysis using distributed activation energy model.

    PubMed

    Bhavanam, Anjireddy; Sastry, R C

    2015-02-01

    The pyrolysis characteristics of municipal solid waste, agricultural residues such as ground nut shell, cotton husk and their blends are investigated using non-isothermal thermogravimetric analysis (TGA) with in a temperature range of 30-900 °C at different heating rates of 10 °C, 30 °C and 50 °C/min in inert atmosphere. From the thermograms obtained from TGA, it is observed that the maximum rate of degradation occurred in the second stage of the pyrolysis process for all the solid wastes. The distributed activation energy model (DAEM) is used to study the pyrolysis kinetics of the solid wastes. The kinetic parameters E (activation energy), k0 (frequency factor) are calculated from this model. It is found that the range of activation energies for agricultural residues are lower than the municipal solid waste. The activation energies for the municipal solid waste pyrolysis process drastically decreased with addition of agricultural residues. The proposed DAEM is successfully validated with TGA experimental data.

  5. Phytochemical profile, antioxidant and antimicrobial activity of extracts obtained from erva-mate (Ilex paraguariensis) fruit using compressed propane and supercritical CO2.

    PubMed

    Fernandes, Ciro E F; Scapinello, Jaqueline; Bohn, Aline; Boligon, Aline A; Athayde, Margareth L; Magro, Jacir Dall; Palliga, Marshall; Oliveira, J Vladimir; Tres, Marcus V

    2017-01-01

    Traditionally, Ilex paraguariensis leaves are consumed in tea form or as typical drinks like mate and terere, while the fruits are discarded processing and has no commercial value. The aim of this work to evaluate phytochemical properties, total phenolic compounds, antioxidant and antimicrobial activity of extracts of Ilex paraguariensis fruits obtained from supercritical CO2 and compressed propane extraction. The extraction with compressed propane yielded 2.72 wt%, whereas with supercritical CO2 1.51 wt% was obtained. The compound extracted in larger amount by the two extraction solvents was caffeine, 163.28 and 54.17 mg/g by supercritical CO2 and pressurized propane, respectively. The antioxidant activity was more pronounced for the supercritical CO2 extract, with no difference found in terms of minimum inhibitory concentration for Staphylococcus aureus for the two extracts and better results observed for Escherichia coli when using supercritical CO2.

  6. Chemical Composition and Biological Activity of Extracts Obtained by Supercritical Extraction and Ethanolic Extraction of Brown, Green and Red Propolis Derived from Different Geographic Regions in Brazil.

    PubMed

    Machado, Bruna Aparecida Souza; Silva, Rejane Pina Dantas; Barreto, Gabriele de Abreu; Costa, Samantha Serra; Silva, Danielle Figuerêdo da; Brandão, Hugo Neves; Rocha, José Luiz Carneiro da; Dellagostin, Odir Antônio; Henriques, João Antônio Pegas; Umsza-Guez, Marcelo Andres; Padilha, Francine Ferreira

    2016-01-01

    The variations in the chemical composition, and consequently, on the biological activity of the propolis, are associated with its type and geographic origin. Considering this fact, this study evaluated propolis extracts obtained by supercritical extraction (SCO2) and ethanolic extraction (EtOH), in eight samples of different types of propolis (red, green and brown), collected from different regions in Brazil. The content of phenolic compounds, flavonoids, in vitro antioxidant activity (DPPH and ABTS), Artepillin C, p-coumaric acid and antimicrobial activity against two bacteria were determined for all extracts. For the EtOH extracts, the anti-proliferative activity regarding the cell lines of B16F10, were also evaluated. Amongst the samples evaluated, the red propolis from the Brazilian Northeast (states of Sergipe and Alagoas) showed the higher biological potential, as well as the larger content of antioxidant compounds. The best results were shown for the extracts obtained through the conventional extraction method (EtOH). However, the highest concentrations of Artepillin C and p-coumaric acid were identified in the extracts from SCO2, indicating a higher selectivity for the extraction of these compounds. It was verified that the composition and biological activity of the Brazilian propolis vary significantly, depending on the type of sample and geographical area of collection.

  7. Chemical Composition and Biological Activity of Extracts Obtained by Supercritical Extraction and Ethanolic Extraction of Brown, Green and Red Propolis Derived from Different Geographic Regions in Brazil

    PubMed Central

    Machado, Bruna Aparecida Souza; Silva, Rejane Pina Dantas; Barreto, Gabriele de Abreu; Costa, Samantha Serra; da Silva, Danielle Figuerêdo; Brandão, Hugo Neves; da Rocha, José Luiz Carneiro; Dellagostin, Odir Antônio; Henriques, João Antônio Pegas; Umsza-Guez, Marcelo Andres; Padilha, Francine Ferreira

    2016-01-01

    The variations in the chemical composition, and consequently, on the biological activity of the propolis, are associated with its type and geographic origin. Considering this fact, this study evaluated propolis extracts obtained by supercritical extraction (SCO2) and ethanolic extraction (EtOH), in eight samples of different types of propolis (red, green and brown), collected from different regions in Brazil. The content of phenolic compounds, flavonoids, in vitro antioxidant activity (DPPH and ABTS), Artepillin C, p-coumaric acid and antimicrobial activity against two bacteria were determined for all extracts. For the EtOH extracts, the anti-proliferative activity regarding the cell lines of B16F10, were also evaluated. Amongst the samples evaluated, the red propolis from the Brazilian Northeast (states of Sergipe and Alagoas) showed the higher biological potential, as well as the larger content of antioxidant compounds. The best results were shown for the extracts obtained through the conventional extraction method (EtOH). However, the highest concentrations of Artepillin C and p-coumaric acid were identified in the extracts from SCO2, indicating a higher selectivity for the extraction of these compounds. It was verified that the composition and biological activity of the Brazilian propolis vary significantly, depending on the type of sample and geographical area of collection. PMID:26745799

  8. Iowa Developed Energy Activity Sampler (IDEAS), Grades 7-12: Language Arts.

    ERIC Educational Resources Information Center

    Simonis, Doris G.

    Presented is the Language Arts component of the Iowa Developed Energy Activity Sampler (IDEAS), a multidisciplinary energy education program designed for infusion into the curriculum of grades 7-12. Among the lessons included are an energy debate, puzzles, energy poetry, and energy life styles. Also contained in the IDEAS program are activity sets…

  9. Iowa Developed Energy Activity Sampler: 6-12. Social Studies. Revised 1987.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines.

    Thirty-eight energy related classroom activities for sixth to twelfth grade are included in this document. The activities are based on the following conceptual themes: (1) energy is basic; (2) energy's usefulness is limited; (3) energy exchanges affect the environment; (4) energy conservation is essential; and (5) people can develop and share…

  10. Nonadiabatic coupling reduces the activation energy in thermally activated delayed fluorescence.

    PubMed

    Gibson, J; Penfold, T J

    2017-03-22

    The temperature dependent rate of a thermally activated process is given by the Arrhenius equation. The exponential decrease in the rate with activation energy, which this imposes, strongly promotes processes with small activation barriers. This criterion is one of the most challenging during the design of thermally activated delayed fluorescence (TADF) emitters used in organic light emitting diodes. The small activation energy is usually achieved with donor-acceptor charge transfer complexes. However, this sacrifices the radiative rate and is therefore incommensurate with the high luminescence quantum yields required for applications. Herein we demonstrate that the spin-vibronic mechanism, operative for efficient TADF, overcomes this limitation. Nonadiabatic coupling between the lowest two triplet states give rise to a strong enhancement of the rate of reserve intersystem crossing via a second order mechanism and promotes population transfer between the T1 to T2 states. Consequently the rISC mechanism is actually operative between initial and final state exhibiting an energy gap that is smaller than between the T1 and S1 states. This contributes to the small activation energies for molecules exhibiting a large optical gap, identifies limitations of the present design procedures and provides a basis from which to construct TADF molecules with simultaneous high radiative and rISC rates.

  11. Analysing domestic activity to reduce household energy consumption.

    PubMed

    Fréjus, Myriam; Guibourdenche, Julien

    2012-01-01

    This paper presents our reflections on the issue of behavioral change according to energy conservation constraints and on the status of sustainability in the design of ambient interactive systems at home. We point out how ergonomics contributes to the study of human factors underlying energy consumption. Relating to situated cognition and human computer interaction, our approach relies both on the ergonomic evaluation of feedback consumption displays and on the modeling of domestic activities in order to identify household concerns in real settings. We present empirical results to illustrate this global approach. The results of those studies allow the design of interactive systems: informative and pedagogical systems as well as pervasive and adaptive ambient systems. In our approach, sustainability is taken into account as a design criterion, as security could be, whereas the main design purpose is to aid households in their daily life in order to build a "sustainable situation".

  12. Activation Energies of Fragmentations of Disaccharides by Tandem Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Kuki, Ákos; Nagy, Lajos; Szabó, Katalin E.; Antal, Borbála; Zsuga, Miklós; Kéki, Sándor

    2014-03-01

    A simple multiple collision model for collision induced dissociation (CID) in quadrupole was applied for the estimation of the activation energy (Eo) of the fragmentation processes for lithiated and trifluoroacetated disaccharides, such as maltose, cellobiose, isomaltose, gentiobiose, and trehalose. The internal energy-dependent rate constants k(Eint) were calculated using the Rice-Ramsperger-Kassel-Marcus (RRKM) or the Rice-Ramsperger-Kassel (RRK) theory. The Eo values were estimated by fitting the calculated survival yield (SY) curves to the experimental ones. The calculated Eo values of the fragmentation processes for lithiated disaccharides were in the range of 1.4-1.7 eV, and were found to increase in the order trehalose < maltose < isomaltose < cellobiose < gentiobiose.

  13. Exploring Metrics to Express Energy Expenditure of Physical Activity in Youth

    PubMed Central

    McMurray, Robert G.; Butte, Nancy F.; Crouter, Scott E.; Trost, Stewart G.; Pfeiffer, Karin A.; Bassett, David R.; Puyau, Maurice R.; Berrigan, David; Watson, Kathleen B.; Fulton, Janet E.

    2015-01-01

    Background Several approaches have been used to express energy expenditure in youth, but no consensus exists as to which best normalizes data for the wide range of ages and body sizes across a range of physical activities. This study examined several common metrics for expressing energy expenditure to determine whether one metric can be used for all healthy children. Such a metric could improve our ability to further advance the Compendium of Physical Activities for Youth. Methods A secondary analysis of oxygen uptake (VO2) data obtained from five sites was completed, that included 947 children ages 5 to 18 years, who engaged in 14 different activities. Resting metabolic rate (RMR) was computed based on Schofield Equations [Hum Nutr Clin Nut. 39(Suppl 1), 1985]. Absolute oxygen uptake (ml.min-1), oxygen uptake per kilogram body mass (VO2 in ml.kg-1.min-1), net oxygen uptake (VO2 – resting metabolic rate), allometric scaled oxygen uptake (VO2 in ml.kg-0.75.min-1) and YOUTH-MET (VO2.[resting VO2] -1) were calculated. These metrics were regressed with age, sex, height, and body mass. Results Net and allometric-scaled VO2, and YOUTH-MET were least associated with age, sex and physical characteristics. For moderate-to-vigorous intensity activities, allometric scaling was least related to age and sex. For sedentary and low-intensity activities, YOUTH-MET was least related to age and sex. Conclusions No energy expenditure metric completely eliminated the influence of age, physical characteristics, and sex. The Adult MET consistently overestimated EE. YOUTH-MET was better for expressing energy expenditure for sedentary and light activities, whereas allometric scaling was better for moderate and vigorous intensity activities. From a practical perspective, The YOUTH-MET may be the more feasible metric for improving of the Compendium of Physical Activities for Youth. PMID:26102204

  14. Nanoscale friction as a function of activation energies

    NASA Astrophysics Data System (ADS)

    Chong, W. W. F.; Rahnejat, H.

    2015-12-01

    Understanding the scale-dependence of friction is increasingly viewed as a critical quest. With progressively thinner films, mixed and boundary regimes of lubrication have become commonplace. Therefore, at the micro-scale a greater need for mitigating friction is desired in order to improve operational efficiency of many machines and mechanisms. Furthermore, there is a growing tendency to use low friction hard wear-resistant advanced coatings to guard against wear. In parallel, there has been much attention paid to lubricant rheology and formulation. However, only in recent times there has been an emerging view of lubricant-surface combination as a system. In this perspective it is essential to relate the observed and measured friction at component level to the underlying interactions in micro/nano-scales. This is the approach in this paper. Observed phenomenon at micro-scale are related back to the activation energies of lubricant-surface system, providing in particular results for surface modified Ni-SiC coated specimen in combination with formulated lubricants, the combination of which represent the lubricant-surface system of choice in cylinders of high performance race engine. The nano-scale conjunction of an AFM tip with lubricated surface-engineered specimen, subjected to various conjunctional loading and sliding kinematics is investigated. It is shown that the measured frictional characteristics can be adequately described in terms of activation energies in line with the Eyring’s thermal activation model for cases of fairly smooth asperity tip contact conjunctions.

  15. Cytosolic calcium coordinates mitochondrial energy metabolism with presynaptic activity.

    PubMed

    Chouhan, Amit K; Ivannikov, Maxim V; Lu, Zhongmin; Sugimori, Mutsuyuki; Llinas, Rodolfo R; Macleod, Gregory T

    2012-01-25

    Most neurons fire in bursts, imposing episodic energy demands, but how these demands are coordinated with oxidative phosphorylation is still unknown. Here, using fluorescence imaging techniques on presynaptic termini of Drosophila motor neurons (MNs), we show that mitochondrial matrix pH (pHm), inner membrane potential (Δψm), and NAD(P)H levels ([NAD(P)H]m) increase within seconds of nerve stimulation. The elevations of pHm, Δψm, and [NAD(P)H]m indicate an increased capacity for ATP production. Elevations in pHm were blocked by manipulations that blocked mitochondrial Ca2+ uptake, including replacement of extracellular Ca2+ with Sr2+ and application of either tetraphenylphosphonium chloride or KB-R7943, indicating that it is Ca2+ that stimulates presynaptic mitochondrial energy metabolism. To place this phenomenon within the context of endogenous neuronal activity, the firing rates of a number of individually identified MNs were determined during fictive locomotion. Surprisingly, although endogenous firing rates are significantly different, there was little difference in presynaptic cytosolic Ca2+ levels ([Ca2+]c) between MNs when each fires at its endogenous rate. The average [Ca2+]c level (329±11 nM) was slightly above the average Ca2+ affinity of the mitochondria (281±13 nM). In summary, we show that when MNs fire at endogenous rates, [Ca2+]c is driven into a range where mitochondria rapidly acquire Ca2+. As we also show that Ca2+ stimulates presynaptic mitochondrial energy metabolism, we conclude that [Ca2+]c levels play an integral role in coordinating mitochondrial energy metabolism with presynaptic activity in Drosophila MNs.

  16. Cytosolic Calcium Coordinates Mitochondrial Energy Metabolism with Presynaptic Activity

    PubMed Central

    Chouhan, Amit K.; Ivannikov, Maxim V.; Lu, Zhongmin; Sugimori, Mutsuyuki; Llinas, Rodolfo R.; Macleod, Gregory T.

    2012-01-01

    Most neurons fire in bursts, imposing episodic energy demands, but how these demands are coordinated with oxidative phosphorylation is still unknown. Here, using fluorescence imaging techniques on presynaptic termini of Drosophila motor neurons (MNs), we show that mitochondrial matrix pH (pHm), inner membrane potential (Δψm), and NAD(P)H levels ([NAD(P)H]m) increase within seconds of nerve stimulation. The elevations of pHm, Δψm, and [NAD(P)H]m indicate an increased capacity for ATP production. Elevations in pHm were blocked by manipulations which blocked mitochondrial Ca2+ uptake, including replacement of extracellular Ca2+ with Sr2+, and application of either tetraphenylphosphonium chloride or KB-R7943, indicating that it is Ca2+ that stimulates presynaptic mitochondrial energy metabolism. To place this phenomenon within the context of endogenous neuronal activity, the firing rates of a number of individually identified MNs were determined during fictive locomotion. Surprisingly, although endogenous firing rates are significantly different, there was little difference in presynaptic cytosolic Ca2+ levels ([Ca2+]c) between MNs when each fires at its endogenous rate. The average [Ca2+]c level (329±11nM) was slightly above the average Ca2+ affinity of the mitochondria (281±13nM). In summary, we show that when MNs fire at endogenous rates [Ca2+]c is driven into a range where mitochondria rapidly acquire Ca2+. As we also show that Ca2+ stimulates presynaptic mitochondrial energy metabolism, we conclude that [Ca2+]c levels play an integral role in coordinating mitochondrial energy metabolism with presynaptic activity in Drosophila MNs. PMID:22279208

  17. Energy in Mexico: a profile of solar energy activity in its national context

    SciTech Connect

    Hawkins, D.

    1980-04-01

    The geopolitical, economic, and cultural aspects of the United States of Mexico are presented. Mexico's energy profile includes the following: energy policy objectives, government energy structure, organizations for implementation, indigeneous energy sources, imported energy sources, solar energy research and development, solar energy organizations and solar energy related legislation and administrative policies. International agreements, contacts, manufacturers, and projects are listed. (MRH)

  18. Constrained Total Energy Expenditure and Metabolic Adaptation to Physical Activity in Adult Humans.

    PubMed

    Pontzer, Herman; Durazo-Arvizu, Ramon; Dugas, Lara R; Plange-Rhule, Jacob; Bovet, Pascal; Forrester, Terrence E; Lambert, Estelle V; Cooper, Richard S; Schoeller, Dale A; Luke, Amy

    2016-02-08

    Current obesity prevention strategies recommend increasing daily physical activity, assuming that increased activity will lead to corresponding increases in total energy expenditure and prevent or reverse energy imbalance and weight gain [1-3]. Such Additive total energy expenditure models are supported by exercise intervention and accelerometry studies reporting positive correlations between physical activity and total energy expenditure [4] but are challenged by ecological studies in humans and other species showing that more active populations do not have higher total energy expenditure [5-8]. Here we tested a Constrained total energy expenditure model, in which total energy expenditure increases with physical activity at low activity levels but plateaus at higher activity levels as the body adapts to maintain total energy expenditure within a narrow range. We compared total energy expenditure, measured using doubly labeled water, against physical activity, measured using accelerometry, for a large (n = 332) sample of adults living in five populations [9]. After adjusting for body size and composition, total energy expenditure was positively correlated with physical activity, but the relationship was markedly stronger over the lower range of physical activity. For subjects in the upper range of physical activity, total energy expenditure plateaued, supporting a Constrained total energy expenditure model. Body fat percentage and activity intensity appear to modulate the metabolic response to physical activity. Models of energy balance employed in public health [1-3] should be revised to better reflect the constrained nature of total energy expenditure and the complex effects of physical activity on metabolic physiology.

  19. Physical Activity Energy Expenditure in Dutch Adolescents: Contribution of Active Transport to School, Physical Education, and Leisure Time Activities

    ERIC Educational Resources Information Center

    Slingerland, Menno; Borghouts, Lars B.; Hesselink, Matthijs K. C.

    2012-01-01

    Background: Detailed knowledge about physical activity energy expenditure (PAEE) can guide the development of school interventions aimed at reducing overweight in adolescents. However, relevant components of PAEE have never been objectively quantified in this population. This study investigated the contribution of active transport to and from…

  20. Macroautophagy regulates energy metabolism during effector T cell activation.

    PubMed

    Hubbard, Vanessa M; Valdor, Rut; Patel, Bindi; Singh, Rajat; Cuervo, Ana Maria; Macian, Fernando

    2010-12-15

    Macroautophagy is a highly conserved mechanism of lysosomal-mediated protein degradation that plays a key role in maintaining cellular homeostasis by recycling amino acids, reducing the amount of damaged proteins, and regulating protein levels in response to extracellular signals. We have found that macroautophagy is induced after effector T cell activation. Engagement of the TCR and CD28 results in enhanced microtubule-associated protein 1 light chain 3 (LC3) processing, increased numbers of LC3-containing vesicles, and increased LC3 flux, indicating active autophagosome formation and clearance. The autophagosomes formed in stimulated T cells actively fuse with lysosomes to degrade their cargo. Using a conditional KO mouse model where Atg7, a critical gene for macroautophagy, is specifically deleted in T cells, we have found that macroautophagy-deficient effector Th cells have defective IL-2 and IFN-γ production and reduced proliferation after stimulation, with no significant increase in apoptosis. We have found that ATP generation is decreased when autophagy is blocked, and defects in activation-induced cytokine production are restored when an exogenous energy source is added to macroautophagy-deficient T cells. Furthermore, we present evidence showing that the nature of the cargo inside autophagic vesicles found in resting T cells differs from the cargo of autophagosomes in activated T cells, where mitochondria and other organelles are selectively excluded. These results suggest that macroautophagy is an actively regulated process in T cells that can be induced in response to TCR engagement to accommodate the bioenergetic requirements of activated T cells.

  1. Synthesis and antileishmanial activity of 6-mono-substituted and 3,6-di-substituted acridines obtained by acylation of proflavine.

    PubMed

    Di Giorgio, Carole; Shimi, Kamal; Boyer, Gérard; Delmas, Florence; Galy, Jean-Pierre

    2007-10-01

    Two new series of diaminoacridinic derivatives obtained from proflavine and N-(6-amino-3-acridinyl)acetamide were synthesised and assessed for their cytotoxic and antileishmanial activities. Two compounds, N-[6-(acetylamino)-3-acridinyl]acetamide and N-[6-(benzoylamino)-3-acridinyl]benzamide demonstrated highly specific antileishmanial properties against the intracellular amastigote form of the parasite. Structure-activity relationships established that the antiproliferative activity against human cells was greatly enhanced by the presence of a benzoylamino group in 6-mono-substituted acridines, while the presence of two acetylamino or benzoylamino groups in 3,6-di-substituted acridines strongly increased the specificity of the molecules for Leishmania parasite, suggesting that symmetric conformations could preferentially interfere with Leishmania metabolism.

  2. Annotated compound data for modulators of detergent-solubilised or lipid-reconstituted respiratory type II NADH dehydrogenase activity obtained by compound library screening

    PubMed Central

    Dunn, Elyse A.; Cook, Gregory M.; Heikal, Adam

    2015-01-01

    The energy-generating membrane protein NADH dehydrogenase (NDH-2), a proposed antibacterial drug target (see “Inhibitors of type II NADH:menaquinone oxidoreductase represent a class of antitubercular drugs” Weinstein et al. 2005 [1]), was screened for modulators of activity in either detergent-solublised or lipid reconstituted (proteolipsome) form. Here we present an annotated list of compounds identified in a small-scale screen against NDH-2. The dataset contains information regarding the libraries screened, the identities of hit compounds and the physicochemical properties governing solubility and permeability. The implications of these data for future antibiotic discovery are discussed in our associated report, “Comparison of lipid and detergent enzyme environments for identifying inhibitors of membrane-bound energy-transducing proteins” [2]. PMID:26862571

  3. Annotated compound data for modulators of detergent-solubilised or lipid-reconstituted respiratory type II NADH dehydrogenase activity obtained by compound library screening.

    PubMed

    Dunn, Elyse A; Cook, Gregory M; Heikal, Adam

    2016-03-01

    The energy-generating membrane protein NADH dehydrogenase (NDH-2), a proposed antibacterial drug target (see "Inhibitors of type II NADH:menaquinone oxidoreductase represent a class of antitubercular drugs" Weinstein et al. 2005 [1]), was screened for modulators of activity in either detergent-solublised or lipid reconstituted (proteolipsome) form. Here we present an annotated list of compounds identified in a small-scale screen against NDH-2. The dataset contains information regarding the libraries screened, the identities of hit compounds and the physicochemical properties governing solubility and permeability. The implications of these data for future antibiotic discovery are discussed in our associated report, "Comparison of lipid and detergent enzyme environments for identifying inhibitors of membrane-bound energy-transducing proteins" [2].

  4. Energy Conservation Education for New York State. Interdisciplinary Learning Activities. Grades 7-12.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany.

    Provided in this document are 18 energy conservation activities designed to supplement regular classroom learning activities. A matrix correlating activity number with grade level and subject areas is included. Titles of activities are: puzzles; energy quiz; energy-related careers; reading a meter; trading calories for kilo-watts; conserving home…

  5. Social Studies. Iowa Developed Energy Activity Sampler, 6-12. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines. Div. of Instructional Services.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This document provides activities for teachers to use with students in teaching social studies. The activities are intended to demonstrate the impact of energy technology on today's society.…

  6. Energy- and Activity-Dependent Loss Timescales for Inner Magnetospheric keV-Energy Electrons

    NASA Astrophysics Data System (ADS)

    Liemohn, M. W.

    2011-12-01

    The Hot Electron and Ion Drift Integrator (HEIDI) inner magnetospheric drift physics model has recently been modified to include keV-energy electron scattering rates by VLF chorus and hiss waves, thus allowing for the calculation of the electron phase space distribution in the inner magnetosphere and electron precipitation to the upper atmosphere. Comparisons of calculated electron fluxes are made with low-Earth orbit electron precipitation data and dayside electron measurements to validate the scattering implementation procedure. The energy-dependent scattering rate coefficients are adjusted to take into account geomagnetic activity and plasmapause location, providing a scattering rate that best matches the simulations to the observed electron fluxes. In addition, the electron ring current intensities and spatio-temporal evolution are compared against simulation results for the hot ion species. While the electron total energy content is typically 10 times smaller than the ion total energy content in the inner magnetosphere, it can be significantly higher than this during the late main phase of magnetic storms.

  7. Macroalga Padina pavonica water extracts obtained by pressurized liquid extraction and microwave-assisted extraction inhibit hyaluronidase activity as shown by capillary electrophoresis.

    PubMed

    Fayad, Syntia; Nehmé, Reine; Tannoury, Mona; Lesellier, Eric; Pichon, Chantal; Morin, Philippe

    2017-03-20

    Hyaluronidase degrades hyaluronic acid, the principal component of the extracellular matrix. Inhibition of this enzyme is thus expected to hinder skin aging. Brown alga Padina pavonica activity toward hyaluronidase was evaluated using capillary electrophoresis (CE)-based enzymatic assays. This green technique allows evaluation of the biological activity of the natural material in an economic manner. Pressurized liquid extraction (PLE), microwave assisted extraction (MAE), supercritical fluid extraction and electroporation extraction techniques were used. Extraction conditions were optimized to obtain cosmetically acceptable Padina pavonica extracts with the best inhibition activity. CE-based assays were conducted using only a few nanoliters of reactants, a capillary of 60cm total length and of 50μm internal diameter, +20kV voltage for separation in 50mM ammonium acetate buffer (pH 9.0) and 200nm wavelength for detection. The reaction mixture was incubated for 1h and CE analysis time was about 11min. A novel online CE-assay using transverse diffusion of laminar flow profiles for in-capillary reactant mixing allowed efficient monitoring of hyaluronidase kinetics with Km and Vmax equal to 0.46±0.04mgmL(-1) and 137.1±0.3nMs(-1) (r(2)=0.99; n=3), respectively. These values compared well with literature, which validates the assay. Water extracts obtained by PLE (60°C; 2 cycles) and MAE (60°C; 1000W; 2min) presented the highest anti-hyaluronidase activity. The half maximal effective concentration (IC50) of water PLE extract was 0.04±0.01mgmL(-1) (r(2)=0.99; n=3). This value is comparable to the one obtained for Einsenia bicyclis phlorotannin fractions (IC50=0.03mgmL(-1)), which makes Padina pavonica bioactivity very promising.

  8. Directed energy active illumination for near-Earth object detection

    NASA Astrophysics Data System (ADS)

    Riley, Jordan; Lubin, Philip; Hughes, Gary B.; O'Neill, Hugh; Meinhold, Peter; Suen, Jonathan; Bible, Johanna; Johansson, Isabella E.; Griswold, Janelle; Cook, Brianna

    2014-09-01

    On 15 February 2013, a previously unknown ~20 m asteroid struck Earth near Chelyabinsk, Russia, releasing kinetic energy equivalent to ~570 kt TNT. Detecting objects like the Chelyabinsk impactor that are orbiting near Earth is a difficult task, in part because such objects spend much of their own orbits in the direction of the Sun when viewed from Earth. Efforts aimed at protecting Earth from future impacts will rely heavily on continued discovery. Ground-based optical observatory networks and Earth-orbiting spacecraft with infrared sensors have dramatically increased the pace of discovery. Still, less than 5% of near-Earth objects (NEOs) >=100 m/~100 Mt TNT have been identified, and the proportion of known objects decreases rapidly for smaller sizes. Low emissivity of some objects also makes detection by passive sensors difficult. A proposed orbiting laser phased array directed energy system could be used for active illumination of NEOs, enhancing discovery particularly for smaller and lower emissivity objects. Laser fiber amplifiers emit very narrow-band energy, simplifying detection. Results of simulated illumination scenarios are presented based on an orbiting emitter array with specified characteristics. Simulations indicate that return signals from small and low emissivity objects is strong enough to detect. The possibility for both directed and full sky blind surveys is discussed, and the resulting diameter and mass limits for objects in different observational scenarios. The ability to determine both position and speed of detected objects is also discussed.

  9. Redox Active Polymers as Soluble Nanomaterials for Energy Storage.

    PubMed

    Burgess, Mark; Moore, Jeffrey S; Rodríguez-López, Joaquín

    2016-11-15

    It is an exciting time for exploring the synergism between the chemical and dimensional properties of redox nanomaterials for addressing the manifold performance demands faced by energy storage technologies. The call for widespread adoption of alternative energy sources requires the combination of emerging chemical concepts with redesigned battery formats. Our groups are interested in the development and implementation of a new strategy for nonaqueous flow batteries (NRFBs) for grid energy storage. Our motivation is to solve major challenges in NRFBs, such as the lack of membranes that simultaneously allow fast ion transport while minimizing redox active species crossover between anolyte (negative electrolyte) and catholyte (positive electrolyte) compartments. This pervasive crossover leads to deleterious capacity fade and materials underutilization. In this Account, we highlight redox active polymers (RAPs) and related polymer colloids as soluble nanoscopic energy storing units that enable the simple but powerful size-exclusion concept for NRFBs. Crossover of the redox component is suppressed by matching high molecular weight RAPs with simple and inexpensive nanoporous commercial separators. In contrast to the vast literature on the redox chemistry of electrode-confined polymer films, studies on the electrochemistry of solubilized RAPs are incipient. This is due in part to challenges in finding suitable solvents that enable systematic studies on high polymers. Here, viologen-, ferrocene- and nitrostyrene-based polymers in various formats exhibit properties that make amenable their electrochemical exploration as solution-phase redox couples. A main finding is that RAP solutions store energy efficiently and reversibly while offering chemical modularity and size versatility. Beyond the practicality toward their use in NRFBs, the fundamental electrochemistry exhibited by RAPs is fascinating, showing clear distinctions in behavior from that of small molecules. Whereas

  10. Activation energy of the low-load NaCl transition from nanoindentation loading curves.

    PubMed

    Kaupp, Gerd

    2014-01-01

    Access to activation energies E(a) of phase transitions is opened by unprecedented analyses of temperature dependent nanoindentation loading curves. It is based on kinks in linearized loading curves, with additional support by coincidence of kink and electrical conductivity of silicon loading curves. Physical properties of B1, B2, NaCl and further phases are discussed. The normalized low-load transition energy of NaCl (Wtrans/µN) increases with temperature and slightly decreases with load. Its semi-logarithmic plot versus T obtains activation energy E(a)/µN for calculation of the transition work for all interesting temperatures and pressures. Arrhenius-type activation energy (kJ/mol) is unavailable for indentation phase transitions. The E(a) per load normalization proves insensitive to creep-on-load, which excludes normalization to depth or volume for large temperature ranges. Such phase transition E(a)/µN is unprecedented material's property and will be of practical importance for the compatibility of composite materials under impact and further shearing interactions at elevated temperatures.

  11. Redox Active Colloids as Discrete Energy Storage Carriers.

    PubMed

    Montoto, Elena C; Nagarjuna, Gavvalapalli; Hui, Jingshu; Burgess, Mark; Sekerak, Nina M; Hernández-Burgos, Kenneth; Wei, Teng-Sing; Kneer, Marissa; Grolman, Joshua; Cheng, Kevin J; Lewis, Jennifer A; Moore, Jeffrey S; Rodríguez-López, Joaquín

    2016-10-12

    Versatile and readily available battery materials compatible with a range of electrode configurations and cell designs are desirable for renewable energy storage. Here we report a promising class of materials based on redox active colloids (RACs) that are inherently modular in their design and overcome challenges faced by small-molecule organic materials for battery applications, such as crossover and chemical/morphological stability. RACs are cross-linked polymer spheres, synthesized with uniform diameters between 80 and 800 nm, and exhibit reversible redox activity as single particles, as monolayer films, and in the form of flowable dispersions. Viologen-based RACs display reversible cycling, accessing up to 99% of their capacity and 99 ± 1% Coulombic efficiency over 50 cycles by bulk electrolysis owing to efficient, long-distance intraparticle charge transfer. Ferrocene-based RACs paired with viologen-based RACs cycled efficiently in a nonaqueous redox flow battery employing a simple size-selective separator, thus demonstrating a possible application that benefits from their colloidal dimensions. The unprecedented versatility in RAC synthetic and electrochemical design opens new avenues for energy storage.

  12. Activation energy of tantalum-tungsten oxide thermite reactions

    SciTech Connect

    Cervantes, Octavio G.; Munir, Zuhair A.; Kuntz, Joshua D.; Gash, Alexander E.

    2011-01-15

    The activation energy of a sol-gel (SG) derived tantalum-tungsten oxide thermite composite was determined using the Kissinger isoconversion method. The SG derived powder was consolidated using the high-pressure spark plasma sintering (HPSPS) technique at 300 and 400 C. The ignition temperatures were investigated under high heating rates (500-2000 C min{sup -1}). Such heating rates were required in order to ignite the thermite composite. Samples consolidated at 300 C exhibit an abrupt change in temperature response prior to the main ignition temperature. This change in temperature response is attributed to the crystallization of the amorphous WO{sub 3} in the SG derived Ta-WO{sub 3} thermite composite and not to a pre-ignition reaction between the constituents. Ignition temperatures for the Ta-WO{sub 3} thermite ranged from approximately 465 to 670 C. The activation energies of the SG derived Ta-WO{sub 3} thermite composite consolidated at 300 and 400 C were determined to be 38{+-} 2 kJ mol{sup -1} and 57 {+-} 2 kJ mol{sup -1}, respectively. (author)

  13. Activation Energy of Tantalum-Tungsten Oxide Thermite Reaction

    SciTech Connect

    Cervantes, O; Kuntz, J; Gash, A; Munir, Z

    2010-02-25

    The activation energy of a high melting temperature sol-gel (SG) derived tantalum-tungsten oxide thermite composite was determined using the Kissinger isoconversion method. The SG derived powder was consolidated using the High Pressure Spark Plasma Sintering (HPSPS) technique to 300 and 400 C to produce pellets with dimensions of 5 mm diameter by 1.5 mm height. A custom built ignition setup was developed to measure ignition temperatures at high heating rates (500-2000 C {center_dot} min{sup -1}). Such heating rates were required in order to ignite the thermite composite. Unlike the 400 C samples, results show that the samples consolidated to 300 C undergo an abrupt change in temperature response prior to ignition. This change in temperature response has been attributed to the crystallization of the amorphous WO{sub 3} in the SG derived Ta-WO{sub 3} thermite composite and not to a pre-ignition reaction between the constituents. Ignition temperatures for the Ta-WO{sub 3} thermite ranged from approximately 465-670 C. The activation energy of the SG derived Ta-WO{sup 3} thermite composite consolidated to 300 and 400 C were determined to be 37.787 {+-} 1.58 kJ {center_dot} mol{sup -1} and 57.381 {+-} 2.26 kJ {center_dot} mol{sup -1}, respectively.

  14. In vitro and in vivo evaluation of the antioxidant and prooxidant activity of phenolic compounds obtained from grape (Vitis vinifera) pomace.

    PubMed

    Cotoras, Milena; Vivanco, Herman; Melo, Ricardo; Aguirre, María; Silva, Evelyn; Mendoza, Leonora

    2014-12-16

    The antioxidant and/or prooxidant ability of extracts obtained from wine waste were analyzed using in vitro and in vivo assays. Cyclic voltammetry was used as the in vitro assay to determine the antioxidant and/or prooxidant properties and, the in vivo effect on mycelial growth of the fungus Botrytis cinerea was evaluated. In addition, the prooxidant activity was evaluated by intracellular oxidation of compound 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) in B. cinerea. The extracts used in this study were obtained from grape pomace of Cabernet Sauvignon, Carménère and Syrah varieties from the Misiones de Rengo Vineyard by simple extraction, using methanol/HCl 1% (v/v), ethanol 70% (v/v), or Soxhlet extraction. According to the results obtained, gallic acid was the most represented phenolic compound independent of grape variety and extraction method. In addition, vanillic acid; protocatechuic acid, syringic acid, quercetin and kaempferol were found in the extracts. From this study it was possible concluded that, depending of the method of extraction of the grape residues and the grape variety (Cabernet Sauvignon, Carménère and Syrah), the extracts showed antioxidant and/or prooxidant activity. However, no correlation can be established between the anodic oxidation potentials of the extracts and their effect on the fungus B. cinerea.

  15. Actively controlled vehicle suspension with energy regeneration capabilities

    NASA Astrophysics Data System (ADS)

    Bar David, Sagiv; Zion Bobrovsky, Ben

    2011-06-01

    The paper presents an innovative dual purpose automotive suspension topology, combining for the first time the active damping qualities with mechanical vibrations power regeneration capabilities. The new configuration consists of a linear generator as an actuator, a power processing stage based on a gyrator operating under sliding mode control and dynamics controllers. The researched design is simple and energetically efficient, enables an accurate force-velocity suspension characteristic control as well as energy regeneration control, with no practical implementation constraints imposed over the theoretical design. Active damping is based on Skyhook suspension control scheme, which enables overcoming the passive damping tradeoff between high- and low-frequency performance, improving both body isolation and the tire's road grip. The system-level design includes configuration of three system operation modes: passive, semi-active or fully active damping, all using the same electro-mechanical infrastructure, and each focusing on different objective: dynamics improvement or power regeneration. Conclusively, the innovative hybrid suspension is theoretically researched, practically designed and analysed, and proven to be feasible as well as profitable in the aspects of power regeneration, vehicle dynamics improvement and human health risks reduction.

  16. Standing wave tube electro active polymer wave energy converter

    NASA Astrophysics Data System (ADS)

    Jean, Philippe; Wattez, Ambroise; Ardoise, Guillaume; Melis, C.; Van Kessel, R.; Fourmon, A.; Barrabino, E.; Heemskerk, J.; Queau, J. P.

    2012-04-01

    Over the past 4 years SBM has developed a revolutionary Wave Energy Converter (WEC): the S3. Floating under the ocean surface, the S3 amplifies pressure waves similarly to a Ruben's tube. Only made of elastomers, the system is entirely flexible, environmentally friendly and silent. Thanks to a multimodal resonant behavior, the S3 is capable of efficiently harvesting wave energy from a wide range of wave periods, naturally smoothing the irregularities of ocean wave amplitudes and periods. In the S3 system, Electro Active Polymer (EAP) generators are distributed along an elastomeric tube over several wave lengths, they convert wave induced deformations directly into electricity. The output is high voltage multiphase Direct Current with low ripple. Unlike other conventional WECs, the S3 requires no maintenance of moving parts. The conception and operating principle will eventually lead to a reduction of both CAPEX and OPEX. By integrating EAP generators into a small scale S3, SBM achieved a world first: direct conversion of wave energy in electricity with a moored flexible submerged EAP WEC in a wave tank test. Through an extensive testing program on large scale EAP generators, SBM identified challenges in scaling up to a utility grid device. French Government supports the consortium consisting of SBM, IFREMER and ECN in their efforts to deploy a full scale prototype at the SEMREV test center in France at the horizon 2014-2015. SBM will be seeking strategic as well as financial partners to unleash the true potentials of the S3 Standing Wave Tube Electro Active Polymer WEC.

  17. Carbon Nanotube Thin Films for Active Noise Cancellation, Solar Energy Harvesting, and Energy Storage in Building Windows

    NASA Astrophysics Data System (ADS)

    Hu, Shan

    other planar supercapacitors in literature by more than one order of magnitude. All-solution fabrication processes were developed for both generations to achieve economical and scalable production. In addition to carbon nanotubes, nickel/nickel oxide core-shell nanowires were also studied as electrode materials for supercapacitors, for which high specific capacitance but low working voltage were obtained. Semi-transparent solar cells with carbon nanotube counter electrodes are developed to power the active noise cancellation system. They can be directly mounted on the glass panes and become part of the home window. The 2.67% efficiency achieved is higher than the 1.8% efficiency required for harvesting adequate energy to cancel noise of 70dB Day-Night-Level, which impacts on a north-facing window. In summary, this project develops several fundamental technologies that together can contribute to a solar-powered active noise cancellation system for a building window. At the same time, since the component technologies being developed are fundamental, it is also likely that they will have wider applications in other domains beyond building windows.

  18. Chemical composition, antioxidant and antimicrobial activities of essential oil obtained from Ferula assa-foetida oleo-gum-resin: effect of collection time.

    PubMed

    Kavoosi, Gholamreza; Rowshan, Vahid

    2013-06-15

    The properties of essential oils obtained from Ferula assa-foetida oleo-gum-resins (OGRs) collectioned in three collections times in 15 June (OGR1), 30 June (OGR2) and 15 July (OGR3) 2011 was investigated. Essential oil from OGR1 was constituted high levels of (E)-1-propenyl sec-butyl disulfide (23.9%) and 10-epi-γ-eudesmol (15.1%). Essential oil from OGR2 was constituted high levels of (Z)-1-propenyl sec-butyl disulfide (27.7%) and (E)-1-propenyl sec-butyl disulfide (20.3%). Essential oil from OGR3 was constituted high levels of β-pinene (47.1%) and α-pinene (21.3%). Inhibitory concentration (IC50) for radical scavenging were 0.012-0.035, 0.025-0.047 and 0.035-0.066 mg/ml of essential oil obtained from OGR1, OGR2 and OGR3, respectively. Minimal inhibitory concentration (MIC) for Gram-positive and Gram-negative bacteria and fungi grpwth were 0.028-0.111, 0.027-0.107 and 0.018-0.058 mg/ml of essential oil obtained from OGR1, OGR2 and OGR3, respectively. Essential oils obtained from different OGRs have different composition and biological activity thus have different applications in food and health industry.

  19. Chemical Characterization of Enteromorpha prolifera Extract Obtained by Enzyme-Assisted Extraction and Its Influence on the Metabolic Activity of Caco-2

    PubMed Central

    Michalak, Izabela; Dmytryk, Agnieszka; Śmieszek, Agnieszka; Marycz, Krzysztof

    2017-01-01

    The green seaweed Enteromorpha prolifera was used as a feedstock for the production of enzymatic hydrolysate using cellulase. The selection of the conditions for enzymatic hydrolysis of the biomass was carried out for different enzyme doses and incubation periods. The obtained extract was examined in terms of its multielemental composition, content of polyphenols and antibacterial properties (tested against Escherichia coli and Staphylococcus aureus). Additionally, its influence on the metabolic activity of human colon epithelial cells (Caco-2) was analyzed. The tested concentrations of extract using an in vitro model were 62.5, 125, 250, 500, 1000 and 2000 µg/mL. The hydrolysis yield in the most suitable experimental conditions (8-h process and 50 and 100 µL of cellulase) was 36%. Micro- and macroelements were poorly extracted from the algal biomass. Total phenolic content was 55 mg of gallic acid equivalent per 100 g of dry mass of extract. The cytotoxic effect of extracts, related to the inhibition of the metabolic activity of Caco-2, was noted only after 24 h. In turn, cultures of Caco-2 propagated with extracts for 72 h were characterized by significantly elevated metabolism (the concentration of extracts ranged from 62.5 to 1000 µg/mL, p < 0.05). Obtained results indicated the high biological activity of the prepared extracts; however, the observed effects did not occur in a dose-dependent manner. PMID:28241482

  20. Antiproliferative activity of flower hexane extract obtained from Mentha spicata associated with Mentha rotundifolia against the MCF7, KB, and NIH/3T3 cell lines.

    PubMed

    Nedel, Fernanda; Begnini, Karine; Carvalho, Pedro Henrique de Azambuja; Lund, Rafael Guerra; Beira, Fátima T A; Del Pino, Francisco Augusto B

    2012-11-01

    This study assessed the antiproliferative effect in vitro of the flower hexane extract obtained from Mentha spicata associated with Mentha rotundifolia against the human breast adenocarcinoma (MCF-7), human mouth epidermal carcinoma (KB), and mouse embryonic fibroblast (NIH 3T3) cell lines, using sulforhodamine B (SRB) assay. A cell density of 2×10(4)/well was seeded in 96-well plates, and samples at different concentrations ranging from 10 to 500 mg/mL were tested. The optical density was determined in an ELISA multiplate reader (Thermo Plate TP-Reader). Results demonstrated that the hexane extract presented antiproliferative activity against both the tumor cell lines KB and MCF-7, presenting a GI(50) (MCF-7=13.09 mg/mL), TGI (KB=37.76 mg/mL), and IL(50) (KB=291.07 mg/mL). Also, the hexane extract presented antiproliferative activity toward NIH 3T3 cells GI(50) (183.65 mg/mL), TGI (280.54 mg/mL), and IL(50) (384.59 mg/mL). The results indicate that the flower hexane extract obtained from M. spicata associated with M. rotundifolia presents an antineoplastic activity against KB and MCF-7, although an antiproliferative effect at a high concentration of the extract was observed toward NIH 3T3.

  1. Nanostructure of Poly(Acrylic Acid) Adsorption Layer on the Surface of Activated Carbon Obtained from Residue After Supercritical Extraction of Hops

    NASA Astrophysics Data System (ADS)

    Wiśniewska, M.; Nosal-Wiercińska, A.; Ostolska, I.; Sternik, D.; Nowicki, P.; Pietrzak, R.; Bazan-Wozniak, A.; Goncharuk, O.

    2017-01-01

    The nanostructure of poly(acrylic acid) (PAA) adsorption layer on the surface of mesoporous-activated carbon HPA obtained by physical activation of residue after supercritical extraction of hops was characterized. This characterization has been done based on the analysis of determination of adsorbed polymer amount, surface charge density, and zeta potential of solid particles (without and in the PAA presence). The SEM, thermogravimetric, FTIR, and MS techniques have allowed one to examine the solid surface morphology and specify different kinds of HPA surface groups. The effects of solution pH, as well as polymer molecular weight and concentration, were studied. The obtained results indicated that the highest adsorption on the activated carbon surface was exhibited by PAA with lower molecular weight (i.e., 2000 Da) at pH 3. Under such conditions, polymeric adsorption layer is composed of nanosized PAA coils (slightly negatively charged) which are densely packed on the positive surface of HPA. Additionally, the adsorption of polymeric macromolecules into solid pores is possible.

  2. Nanostructure of Poly(Acrylic Acid) Adsorption Layer on the Surface of Activated Carbon Obtained from Residue After Supercritical Extraction of Hops.

    PubMed

    Wiśniewska, M; Nosal-Wiercińska, A; Ostolska, I; Sternik, D; Nowicki, P; Pietrzak, R; Bazan-Wozniak, A; Goncharuk, O

    2017-12-01

    The nanostructure of poly(acrylic acid) (PAA) adsorption layer on the surface of mesoporous-activated carbon HPA obtained by physical activation of residue after supercritical extraction of hops was characterized. This characterization has been done based on the analysis of determination of adsorbed polymer amount, surface charge density, and zeta potential of solid particles (without and in the PAA presence). The SEM, thermogravimetric, FTIR, and MS techniques have allowed one to examine the solid surface morphology and specify different kinds of HPA surface groups. The effects of solution pH, as well as polymer molecular weight and concentration, were studied. The obtained results indicated that the highest adsorption on the activated carbon surface was exhibited by PAA with lower molecular weight (i.e., 2000 Da) at pH 3. Under such conditions, polymeric adsorption layer is composed of nanosized PAA coils (slightly negatively charged) which are densely packed on the positive surface of HPA. Additionally, the adsorption of polymeric macromolecules into solid pores is possible.

  3. Statins enhance peroxisome proliferator-activated receptor gamma coactivator-1alpha activity to regulate energy metabolism.

    PubMed

    Wang, Wenxian; Wong, Chi-Wai

    2010-03-01

    Peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) serves as an inducible coactivator for a number of transcription factors to control energy metabolism. Insulin signaling through Akt kinase has been demonstrated to phosphorylate PGC-1alpha at serine 571 and downregulate its activity in the liver. Statins are 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors that reduce cholesterol synthesis in the liver. In this study, we found that statins reduced the active form of Akt and enhanced PGC-1alpha activity. Specifically, statins failed to activate an S571A mutant of PGC-1alpha. The activation of PGC-1alpha by statins selectively enhanced the expression of energy metabolizing enzymes and regulators including peroxisome proliferator-activated receptor alpha, acyl-CoA oxidase, carnitine palmitoyl transferase-1A, and pyruvate dehydrogenase kinase 4. Importantly, a constitutively active form of Akt partially reduced the statin-enhanced gene expression. Our study thus provides a plausible mechanistic explanation for the hypolipidemic effect of statin through elevating the rate of beta-oxidation and mitochondrial Kreb's cycle capacity to enhance fatty acid utilization while reducing the rate of glycolysis.

  4. Biological evaluation of synthesized allicin and its transformation products obtained by microwaves in methanol: antioxidant activity and effect on cell growth.

    PubMed

    Ilić, Dušica P; Stojanović, Sanja; Najman, Stevo; Nikolić, Vesna D; Stanojević, Ljiljana P; Tačić, Ana; Nikolić, Ljubiša B

    2015-01-02

    Allicin is the most biologically active substance present in garlic. It can be synthesized or obtained by extraction of fresh garlic. Transformation products of allicin are also biologically active. The aim of this study was to examine the antioxidant activity of synthesized allicin and its transformation products obtained using microwaves in methanol at 55 °C as well as their effect on HeLa cells growth. The antioxidant activity was determined by DPPH (2,2-diphenyl-1-picrylhydrazyl radical) test. The effect on HeLa cells growth was determined by MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) test. For MTT test, allicin and its transformation products were dispersed in carmellose sodium solution and examined in concentrations ranging from 0.3 μg/mL to 3 mg/mL. Allicin showed stronger antioxidant activity than the transformation products. A maximum degree of neutralization of DPPH radicals, about 90%, was reached when the concentration of allicin was 2 mg/mL, with an EC50 (concentration of sample which is required for reduction of the initial concentration DPPH radicals to 50%) value of 0.37 mg/mL. In our study, allicin and its transformation products were not cytotoxic to HeLa cells under the examined conditions. The highest concentration of allicin and its transformation products had a slight antiproliferative effect, with a more pronounced effect of allicin, which reflected on the morphology of HeLa cells. The examined substances are safe to use on epithelial cells at concentrations up to 3 mg/mL when applied in carmellose sodium solution. Using carmellose sodium as a dispersing agent could be recommended as a good approach for testing liposoluble substances in liquid cell cultures.

  5. Extraction of essential oil from Cupressus sempervirens: comparison of global yields, chemical composition and antioxidant activity obtained by hydrodistillation and supercritical extraction.

    PubMed

    Nejia, Herzi; Séverine, Camy; Jalloul, Bouajila; Mehrez, Romdhane; Stéphane, Condoret Jean

    2013-01-01

    In this study, supercritical fluid extraction (SFE) with CO2 and hydrodistillation (HD) were compared as methods to isolate the essential oil from Cupressus sempervirens. The odour of the oil obtained by SFE at 90 bar and 40°C was very close to the odour of the leaves of C. sempervirens before the extraction. Compounds extracted by both SFE and HD were identified by GC-FID and GC-MS. Moreover, the difference in the chemical composition obtained by SFE and HD was quite noticeable qualitatively and quantitatively. Phenolic composition and antioxidant activity were also determined. Compared to HD, the SFE method presents some advantages: the extraction was completed after 1 h in SFE, although 4 h is necessary for HD, and the yield was improved by 34%. Finally, it has also been shown that SFE is very selective towards some specific components such as manoyl oxide, trans-totarol and α-acoradiene.

  6. Energy spectrum of interplanetary magnetic flux ropes and its connection with solar activity

    NASA Astrophysics Data System (ADS)

    Wu, D. J.; Feng, H. Q.; Chao, J. K.

    2008-03-01

    Context: Recent observations of the solar wind show that interplanetary magnetic flux ropes (IMFRs) have a continuous scale-distribution from small-scale flux ropes to large-scale magnetic clouds. Aims: In this work, we investigate the energy spectrum of IMFRs and its possible connection with solar activity. Methods: In consideration of the detectable probability of an IMFR to be proportional to its diameter, the actual energy spectrum of IMFRs can be obtained from the observed spectrum based on spacecraft observations in the solar wind. Results: It is found that IMFRs have a negative power-law spectrum with an index α = 1.36±0.03, which is similar to that of solar flares, and is probably representative of interplanetary energy spectrum of coronal mass ejections (CMEs), that is, the energy spectrum of interplanetary CMEs (ICMEs). This indicates that the energy distribution of CMEs has a similar negative power-law spectrum. In particular, there are numerous small-scale CMEs in the solar corona, and their interplanetary consequences may be directly detected in situ by spacecraft in the solar wind as small-scale IMFRs, although they are too weak to appear clearly in current coronagraph observations. Conclusions: The presence of small-scale CMEs, especially the energy spectrum of CMEs is potentially important for understanding both the solar magneto-atmosphere and CMEs.

  7. Energy transfer at the active sites of heme proteins

    SciTech Connect

    Dlott, D.D.; Hill, J.R.

    1995-12-31

    Experiments using a picosecond pump-probe apparatus at the Picosecond Free-electron Laser Center at Stanford University, were performed to investigate the relaxation of carbon monoxide bound to the active sites of heme proteins. The significance of these experiments is two-fold: (1) they provide detailed information about molecular dynamics occurring at the active sites of proteins; and (2) they provide insight into the nature of vibrational relaxation processes in condensed matter. Molecular engineering is used to construct various molecular systems which are studied with the FEL. We have studied native proteins, mainly myoglobin obtained from different species, mutant proteins produced by genetic engineering using recombinant DNA techniques, and a variety of model systems which mimic the structures of the active sites of native proteins, which are produced using molecular synthesis. Use of these different systems permits us to investigate how specific molecular structural changes affect dynamical processes occurring at the active sites. This research provides insight into the problems of how different species needs are fulfilled by heme proteins which have greatly different functionality, which is induced by rather small structural changes.

  8. Daily energy expenditure, physical activity, and weight loss in Parkinson's disease patients

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Patients with Parkinson's disease (PD) commonly exhibit weight loss (WL) which investigators attribute to various factors, including elevated energy expenditure. We tested the hypothesis that daily energy expenditure (DEE) and its components, resting energy expenditure (REE) and physical activity (P...

  9. Correlating hydrogen oxidation and evolution activity on platinum at different pH with measured hydrogen binding energy

    SciTech Connect

    Sheng, WC; Zhuang, ZB; Gao, MR; Zheng, J; Chen, JGG; Yan, YS

    2015-01-08

    The hydrogen oxidation/evolution reactions are two of the most fundamental reactions in distributed renewable electrochemical energy conversion and storage systems. The identification of the reaction descriptor is therefore of critical importance for the rational catalyst design and development. Here we report the correlation between hydrogen oxidation/evolution activity and experimentally measured hydrogen binding energy for polycrystalline platinum examined in several buffer solutions in a wide range of electrolyte pH from 0 to 13. The hydrogen oxidation/evolution activity obtained using the rotating disk electrode method is found to decrease with the pH, while the hydrogen binding energy, obtained from cyclic voltammograms, linearly increases with the pH. Correlating the hydrogen oxidation/evolution activity to the hydrogen binding energy renders a monotonic decreasing hydrogen oxidation/evolution activity with the hydrogen binding energy, strongly supporting the hypothesis that hydrogen binding energy is the sole reaction descriptor for the hydrogen oxidation/evolution activity on monometallic platinum.

  10. Validating Accelerometry as a Measure of Physical Activity and Energy Expenditure in Chronic Stroke

    PubMed Central

    Serra, Monica C.; Balraj, Elizabeth; DiSanzo, Beth L.; Ivey, Frederick M.; Hafer-Macko, Charlene E.; Treuth, Margarita S.; Ryan, Alice S.

    2016-01-01

    Background Accelerometers can objectively measure steps taken per day in individuals without gait deficits, but accelerometers also have the ability to estimate frequency, intensity, and duration of physical activity. However, thresholds to distinguish varying levels of activity intensity using the Actical brand accelerometer are standardized only for the general population and may underestimate intensity in stroke. Objective To derive Actical activity count thresholds specific to stroke disability for use in more accurately gauging time spent at differing activity levels. Methods Men (n=18) and women (n=10) with chronic hemiparetic gait (4±2 years latency, 43% Caucasian, 56% African American, ages of 47–83 yrs, BMI 19 – 48 kg/m2) participated in the study. Actical accelerometers were placed on the non-paretic hip to obtain accelerometry counts during eight activities of varying intensity: 1) watching TV; 2) seated stretching; 3) standing stretching; 4) floor sweeping; 5) stepping in place; 6) over-ground walking; 7) lower speed treadmill walking (1.0 mph at 4% incline); and 8) higher speed treadmill walking (2.0 mph at 4% incline). Simultaneous portable monitoring (Cosmed K4b2) enabled quantification of energy cost for each activity in metabolic equivalents (METs, or oxygen consumption in multiples of resting level). Measurements were obtained for 10 min of standard rest and 5 minutes during each of the eight activities. Results Regression analysis yielded the following new stroke-specific Actical minimum thresholds: 125 counts per minute (cpm) for sedentary/light activity, 667 cpm for light/moderate activity, and 1546 cpm for moderate/vigorous activity. Conclusion Our revised cut-points better reflect activity levels after stroke and suggest significantly lower thresholds relative to those observed for the general population of healthy individuals. We conclude that the standard, commonly applied Actical thresholds are inappropriate for this unique population

  11. Results of a Study Investigating the Plant Uptake of Explosive Residues From Compost of Explosives-Contaminated Soil Obtained from the Umatilla Army Depot Activity

    DTIC Science & Technology

    1998-11-01

    Aberdeen Proving Ground, Maryland 21010-5401 POC: Mr. Wayne Sisk Prepared by J. J. Maddox, R. A. Almond , M. F. Broder J. J. Hoagland, D. A. Kelly, W...Compost of Explosives-Contaminated Soil Obtained from the Umatilla Army Depot Activity ___ 12. PERSONAL AUTHOR(S) J. J. Maddox, R. A. Almond , M. F...NUMBER 3-1 Summary of Water (HPLC Purity) Samples Spiked Before Extraction 3-6 3-2 Summary of Leachate Samples Spiked Before Extraction 3-6 3-3

  12. Active galactic nuclei at gamma-ray energies

    NASA Astrophysics Data System (ADS)

    Dermer, Charles Dennison; Giebels, Berrie

    2016-06-01

    Active Galactic Nuclei can be copious extragalactic emitters of MeV-GeV-TeV γ rays, a phenomenon linked to the presence of relativistic jets powered by a super-massive black hole in the center of the host galaxy. Most of γ-ray emitting active galactic nuclei, with more than 1500 known at GeV energies, and more than 60 at TeV energies, are called ;blazars;. The standard blazar paradigm features a jet of relativistic magnetized plasma ejected from the neighborhood of a spinning and accreting super-massive black hole, close to the observer direction. Two classes of blazars are distinguished from observations: the flat-spectrum radio-quasar class (FSRQ) is characterized by strong external radiation fields, emission of broad optical lines, and dust tori. The BL Lac class (from the name of one of its members, BL Lacertae) corresponds to weaker advection-dominated flows with γ-ray spectra dominated by the inverse Compton effect on synchrotron photons. This paradigm has been very successful for modeling the broadband spectral energy distributions of blazars. However, many fundamental issues remain, including the role of hadronic processes and the rapid variability of a few FSRQs and several BL Lac objects whose synchrotron spectrum peaks at UV or X-ray frequencies. A class of γ-ray-emitting radio galaxies, which are thought to be the misaligned counterparts of blazars, has emerged from the results of the Fermi-Large Area Telescope and of ground-based Cherenkov telescopes. Soft γ-ray emission has been detected from a few nearby Seyfert galaxies, though it is not clear whether those γ rays originate from the nucleus. Blazars and their misaligned counterparts make up most of the ≳100 MeV extragalactic γ-ray background (EGB), and are suspected of being the sources of ultra-high energy cosmic rays. The future ;Cherenkov Telescope Array;, in synergy with the Fermi-Large Area Telescope and a wide range of telescopes in space and on the ground, will write the next chapter

  13. Physical Activity Assessment: Biomarkers and Self-Report of Activity-Related Energy Expenditure in the WHI

    PubMed Central

    Neuhouser, Marian L.; Di, Chongzhi; Tinker, Lesley F.; Thomson, Cynthia; Sternfeld, Barbara; Mossavar-Rahmani, Yasmin; Stefanick, Marcia L.; Sims, Stacy; Curb, J. David; Lamonte, Michael; Seguin, Rebecca; Johnson, Karen C.; Prentice, Ross L

    2013-01-01

    We used a biomarker of activity-related energy expenditure (AREE) to assess measurement properties of self-reported physical activity and to determine the usefulness of AREE regression calibration equations in the Women's Health Initiative. Biomarker AREE, calculated as the total energy expenditure from doubly labeled water minus the resting energy expenditure from indirect calorimetry, was assessed in 450 Women's Health Initiative participants (2007–2009). Self-reported AREE was obtained from the Arizona Activity Frequency Questionnaire (AAFQ), the 7-Day Physical Activity Recall (PAR), and the Women's Health Initiative Personal Habits Questionnaire (PHQ). Eighty-eight participants repeated the protocol 6 months later. Reporting error, measured as log(self-report AREE) minus log(biomarker AREE), was regressed on participant characteristics for each instrument. Body mass index was associated with underreporting on the AAFQ and PHQ but overreporting on PAR. Blacks and Hispanics underreported physical activity levels on the AAFQ and PAR, respectively. Underreporting decreased with age for the PAR and PHQ. Regressing logbiomarker AREE on logself-reported AREE revealed that self-report alone explained minimal biomarker variance (R2 = 7.6, 4.8, and 3.4 for AAFQ, PAR, and PHQ, respectively). R2 increased to 25.2, 21.5, and 21.8, respectively, when participant characteristics were included. Six-month repeatability data adjusted for temporal biomarker variation, improving R2 to 79.4, 67.8, and 68.7 for AAFQ, PAR, and PHQ, respectively. Calibration equations “recover” substantial variation in average AREE and valuably enhance AREE self-assessment. PMID:23436896

  14. Jahn-Teller stabilization energies for ZnS:Mn and ZnSe:Mn excited states obtained by the angular overlap model

    NASA Astrophysics Data System (ADS)

    Stavrev, K. K.; Kynev, K. D.; Nikolov, G. St.

    1988-06-01

    Linear Jahn-Teller coupling constants are obtained by the angular overlap model. A comparison with the data published recently [Parrot et al., J. Chem. Phys. 87, 1463 (1987)] is made in order to demonstrate the considerable improvement in the calculated Jahn-Teller coefficients when the parameters of the angular overlap model are extracted from a spectral analysis of the systems under consideration.

  15. Solar energy in Italy: a profile of renewable energy activity in its national context

    SciTech Connect

    Shea, C.A.

    1980-12-01

    The following are included: country overview; energy summary; Italian Republic-geopolitical, economic, and cultural aspects; the energy profile; imported energy sources; solar energy research and development; solar energy organizations; solar energy related legislation and administration policies; and international agreements, contacts, manufacturers, and projects. (MHR)

  16. Contribution of regional brain melanocortin receptor subtypes to elevated activity energy expenditure in lean, active rats

    PubMed Central

    Shukla, Charu; Koch, Lauren G.; Britton, Steven L.; Cai, Minying; Hruby, Victor J.; Bednarek, Maria; Novak, Colleen M.

    2015-01-01

    Physical activity and non-exercise activity thermogenesis (NEAT) are crucial factors accounting for individual differences in body weight, interacting with genetic predisposition. In the brain, a number of neuroendocrine intermediates regulate food intake and energy expenditure (EE); this includes the brain melanocortin (MC) system, consisting of melanocortin peptides as well as their receptors (MCR). MC3R and MC4R have emerged as critical modulators of EE and food intake. To determine how variance in MC signaling may underlie individual differences in physical activity levels, we examined behavioral response to MC receptor agonists and antagonists in rats that show high and low levels of physical activity and NEAT, that is, high- and low-capacity runners (HCR, LCR), developed by artificial selection for differential intrinsic aerobic running capacity. Focusing on the hypothalamus, we identified brain region-specific elevations in expression of MCR 3, 4, and also MC5R, in the highly active, lean HCR relative to the less active and obesity-prone LCR. Further, the differences in activity and associated EE as a result of MCR activation or suppression using specific agonists and antagonists were similarly region-specific and directly corresponded to the differential MCR expression patterns. The agonists and antagonists investigated here did not significantly impact food intake at the doses used, suggesting that the differential pattern of receptor expression may by more meaningful to physical activity than to other aspects of energy balance regulation. Thus, MCR-mediated physical activity may be a key neural mechanism in distinguishing the lean phenotype and a target for enhancing physical activity and NEAT. PMID:26404873

  17. Peroxisome proliferator-activated receptor-α activation and excess energy burning in hepatocarcinogenesis.

    PubMed

    Misra, Parimal; Reddy, Janardan K

    2014-03-01

    Peroxisome proliferator-activated receptor-α (PPARα) modulates the activities of all three interlinked hepatic fatty acid oxidation systems, namely mitochondrial and peroxisomal β-oxidation and microsomal ω-oxidation pathways. Hyperactivation of PPARα, by both exogenous and endogenous activators up-regulates hepatic fatty acid oxidation resulting in excess energy burning in liver contributing to the development of liver cancer in rodents. Sustained PPARα signaling disproportionately increases H2O2-generating fatty acid metabolizing enzymes as compared to H2O2-degrading enzymes in liver leading to enhanced generation of DNA damaging reactive oxygen species, progressive endoplasmic reticulum stress and inflammation. These alterations also contribute to increased liver cell proliferation with changes in apoptosis. Thus, reactive oxygen species, oxidative stress and hepatocellular proliferation are likely the main contributing factors in the pathogenesis of hepatocarcinogenesis, mediated by sustained PPARα activation-related energy burning in liver. Furthermore, the transcriptional co-activator Med1, a key subunit of the Mediator complex, is essential for PPARα signaling in that both PPARα-null and Med1-null hepatocytes are unresponsive to PPARα activators and fail to give rise to liver tumors when chronically exposed to PPARα activators.

  18. Solar Energy Education. Humanities: activities and teacher's guide. Field test edition

    SciTech Connect

    Not Available

    1982-01-01

    Activities are outlined to introduce students to information on solar energy while performing ordinary classroom work. In this teaching manual solar energy is integrated with the humanities. The activities include such things as stories, newspapers, writing assignments, and art and musical presentations all filled with energy related terms. An energy glossary is provided. (BCS)

  19. Assessment of consumption and expenditure data collected from energy suppliers against bill data obtained from interviewed households: Case study with 2009 RECS

    EIA Publications

    2013-01-01

    By comparing the different data sources (survey respondents provide information about their household characteristics and energy use; interviewers used portable devices to scan the respondents’ utility bills), we hope to learn more about any limitations in the data that we collect, which we can then attempt to address. As such, this limited empirical study is an example of the research that EIA conducts to evaluate and subsequently improve on the quality of data that EIA collects.

  20. Activation Energies for an Enzyme-Catalyzed and Acid-Catalyzed Hydrolysis: An Introductory Interdisciplinary Experiment for Chemists and Biochemists.

    ERIC Educational Resources Information Center

    Adams, K. R.; Meyers, M. B.

    1985-01-01

    Background information, procedures used, and typical results obtained are provided for an experiment in which students determine and compare the Arrhenius activation energies (Ea) for the hydrolysis of salicin. This reaction is subject to catalysis both by acid and by the enzyme emulsin (beta-d-glucoside glycohydrolase). (JN)

  1. Ionization energy and active cation vibrations of trans-2-fluorostyrene

    NASA Astrophysics Data System (ADS)

    Wu, Pei Ying; Tzeng, Sheng Yuan; Hsu, Ya Chu; Tzeng, Wen Bih

    2017-02-01

    We applied the two-color resonant two-photon mass-analyzed threshold ionization (MATI) technique to record the cation spectra of trans-2-fluorostyrene by ionizing via six intermediate vibronic levels. The adiabatic ionization energy was determined to be 69 304 ± 5 cm-1. The distinct MATI bands at 67, 124, 242, 355, 737, 806, 833, and 993 cm-1 were assigned to the active cation vibrations related to out-of-plane substituent-sensitive bending vibrations and in-plane ring deformation and bending motions. Many combination vibrations were also observed. Our experimental results suggest that the molecular geometry and vibrational coordinates of the trans-2-fluorostyrene cation in the D0 state resemble those of the neutral species in the S1 state.

  2. Different impressions of other agents obtained through social interaction uniquely modulate dorsal and ventral pathway activities in the social human brain.

    PubMed

    Takahashi, Hideyuki; Terada, Kazunori; Morita, Tomoyo; Suzuki, Shinsuke; Haji, Tomoki; Kozima, Hideki; Yoshikawa, Masahiro; Matsumoto, Yoshio; Omori, Takashi; Asada, Minoru; Naito, Eiichi

    2014-09-01

    Internal (neuronal) representations in the brain are modified by our experiences, and this phenomenon is not unique to sensory and motor systems. Here, we show that different impressions obtained through social interaction with a variety of agents uniquely modulate activity of dorsal and ventral pathways of the brain network that mediates human social behavior. We scanned brain activity with functional magnetic resonance imaging (fMRI) in 16 healthy volunteers when they performed a simple matching-pennies game with a human, human-like android, mechanical robot, interactive robot, and a computer. Before playing this game in the scanner, participants experienced social interactions with each opponent separately and scored their initial impressions using two questionnaires. We found that the participants perceived opponents in two mental dimensions: one represented "mind-holderness" in which participants attributed anthropomorphic impressions to some of the opponents that had mental functions, while the other dimension represented "mind-readerness" in which participants characterized opponents as intelligent. Interestingly, this "mind-readerness" dimension correlated to participants frequently changing their game tactic to prevent opponents from envisioning their strategy, and this was corroborated by increased entropy during the game. We also found that the two factors separately modulated activity in distinct social brain regions. Specifically, mind-holderness modulated activity in the dorsal aspect of the temporoparietal junction (TPJ) and medial prefrontal and posterior paracingulate cortices, while mind-readerness modulated activity in the ventral aspect of TPJ and the temporal pole. These results clearly demonstrate that activity in social brain networks is modulated through pre-scanning experiences of social interaction with a variety of agents. Furthermore, our findings elucidated the existence of two distinct functional networks in the social human brain

  3. Determination of carrier yields for neutron activation analysis using energy dispersive X-ray spectrometry

    USGS Publications Warehouse

    Johnson, R.G.; Wandless, G.A.

    1984-01-01

    A new method is described for determining carrier yield in the radiochemical neutron activation analysis of rare-earth elements in silicate rocks by group separation. The method involves the determination of the rare-earth elements present in the carrier by means of energy-dispersive X-ray fluorescence analysis, eliminating the need to re-irradiate samples in a nuclear reactor after the gamma ray analysis is complete. Results from the analysis of USGS standards AGV-1 and BCR-1 compare favorably with those obtained using the conventional method. ?? 1984 Akade??miai Kiado??.

  4. Home Economics. Iowa Developed Energy Activity Sampler, 6-12. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines. Div. of Instructional Services.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This document was developed to provide home economics teachers with background information on energy, and activities that can be used/adapted with a minimum of preparation time. The…

  5. Solar Energy Education. Social studies: activities and teacher's guide. Field test edition

    SciTech Connect

    Not Available

    1982-01-01

    Solar energy information is made available to students through classroom instruction by way of the Solar Energy Education teaching manuals. In this manual solar energy, as well as other energy sources like wind power, is introduced by performing school activities in the area of social studies. A glossary of energy related terms is included. (BCS)

  6. Cosmic ray primary composition in the energy range 10-1000 TeV obtained by passive balloon-borne detector: Reanalysis of the RUNJOB experiment

    SciTech Connect

    Kopenkin, V.; Sinzi, T.

    2009-04-01

    We search for a consistent view on the RUNJOB experiment and present an alternative analysis based on explicitly reported and published numerical data. Here we show that there is more than one interpretation to the reported observational data. It is demonstrated that, contrary to the wide-spread opinion, the RUNJOB data are not inconsistent with an increase of the average mass near the knee region of the cosmic ray spectrum. Considering very low statistics and systematic uncertainties, especially in the high energy region, we suggest that peculiarities of the methodical origin were the most likely source of those RUNJOB conclusions which contradicted previous observations reported by other groups.

  7. Comparison of Activity Determination of Radium 226 in FUSRAP Soil using Various Energy Lines - 12299

    SciTech Connect

    Tucker, Brian; Donakowski, Jough; Hays, David

    2012-07-01

    Gamma spectroscopy is used at the Formerly Utilized Sites Remedial Action Program (FUSRAP) Maywood Superfund Site as the primary radioanalytical tool for quantization of activities of the radionuclides of concern in site soil. When selecting energy lines in gamma spectroscopy, a number of factors are considered including assumptions concerning secondary equilibrium, interferences, and the strength of the lines. The case of the Maywood radionuclide of concern radium-226 (Ra-226) is considered in this paper. At the FUSRAP Maywood Superfund Site, one of the daughters produced from radioactive decay of Ra-226, lead-214 (Pb- 214), is used to quantitate Ra-226. Another Ra-226 daughter, bismuth-214 (Bi-214), also may be used to quantitate Ra-226. In this paper, a comparison of Ra-226 to Pb-214 activities and Ra-226 to Bi-214 activities, obtained using gamma spectrometry for a large number of soil samples, was performed. The Pb-214, Bi-214, and Ra-226 activities were quantitated using the 352 kilo electron volt (keV), 609 keV, and 186 keV lines, respectively. The comparisons were made after correcting the Ra-226 activities by a factor of 0.571 and both ignoring and accounting for the contribution of a U-235 interfering line to the Ra-226 line. For the Pb-214 and Bi-214 activities, a mean in-growth factor was employed. The gamma spectrometer was calibrated for efficiency and energy using a mixed gamma standard and an energy range of 59 keV to 1830 keV. The authors expect other sites with Ra-226 contamination in soil may benefit from the discussions and points in this paper. Proper use of correction factors and comparison of the data from three different gamma-emitting radionuclides revealed agreement with expectations and provided confidence that using such correction factors generates quality data. The results indicate that if contamination is low level and due to NORM, the Ra-226 can be measured directly if corrected to subtract the contribution from U-235. If there is

  8. Controlling activation site density by low-energy far-field stimulation in cardiac tissue.

    PubMed

    Hörning, Marcel; Takagi, Seiji; Yoshikawa, Kenichi

    2012-06-01

    Tachycardia and fibrillation are potentially fatal arrhythmias associated with the formation of rotating spiral waves in the heart. Presently, the termination of these types of arrhythmia is achieved by use of antitachycardia pacing or cardioversion. However, these techniques have serious drawbacks, in that they either have limited application or produce undesirable side effects. Low-energy far-field stimulation has recently been proposed as a superior therapy. This proposed therapeutic method would exploit the phenomenon in which the application of low-energy far-field shocks induces a large number of activation sites ("virtual electrodes") in tissue. It has been found that the formation of such sites can lead to the termination of undesired states in the heart and the restoration of normal beating. In this study we investigate a particular aspect of this method. Here we seek to determine how the activation site density depends on the applied electric field through in vitro experiments carried out on neonatal rat cardiac tissue cultures. The results indicate that the activation site density increases exponentially as a function of the intracellular conductivity and the level of cell isotropy. Additionally, we report numerical results obtained from bidomain simulations of the Beeler-Reuter model that are quantitatively consistent with our experimental results. Also, we derive an intuitive analytical framework that describes the activation site density and provides useful information for determining the ratio of longitudinal to transverse conductivity in a cardiac tissue culture. The results obtained here should be useful in the development of an actual therapeutic method based on low-energy far-field pacing. In addition, they provide a deeper understanding of the intrinsic properties of cardiac cells.

  9. Controlling activation site density by low-energy far-field stimulation in cardiac tissue

    NASA Astrophysics Data System (ADS)

    Hörning, Marcel; Takagi, Seiji; Yoshikawa, Kenichi

    2012-06-01

    Tachycardia and fibrillation are potentially fatal arrhythmias associated with the formation of rotating spiral waves in the heart. Presently, the termination of these types of arrhythmia is achieved by use of antitachycardia pacing or cardioversion. However, these techniques have serious drawbacks, in that they either have limited application or produce undesirable side effects. Low-energy far-field stimulation has recently been proposed as a superior therapy. This proposed therapeutic method would exploit the phenomenon in which the application of low-energy far-field shocks induces a large number of activation sites (“virtual electrodes”) in tissue. It has been found that the formation of such sites can lead to the termination of undesired states in the heart and the restoration of normal beating. In this study we investigate a particular aspect of this method. Here we seek to determine how the activation site density depends on the applied electric field through in vitro experiments carried out on neonatal rat cardiac tissue cultures. The results indicate that the activation site density increases exponentially as a function of the intracellular conductivity and the level of cell isotropy. Additionally, we report numerical results obtained from bidomain simulations of the Beeler-Reuter model that are quantitatively consistent with our experimental results. Also, we derive an intuitive analytical framework that describes the activation site density and provides useful information for determining the ratio of longitudinal to transverse conductivity in a cardiac tissue culture. The results obtained here should be useful in the development of an actual therapeutic method based on low-energy far-field pacing. In addition, they provide a deeper understanding of the intrinsic properties of cardiac cells.

  10. First determination of the (re)crystallization activation energy of an irradiated olivine-type silicate

    NASA Astrophysics Data System (ADS)

    Djouadi, Z.; D'Hendecourt, L.; Leroux, H.; Jones, A. P.; Borg, J.; Deboffle, D.; Chauvin, N.

    2005-09-01

    To study the evolution of silicate dust in different astrophysical environments we simulate, in the laboratory, interstellar and circumstellar ion irradiation and thermal annealing processes. An experimental protocol that follows different steps in the dust life-cycle was developed. Using the silicate 10 μm band as an indicator, the evolution of the structural properties of an ion-irradiated olivine-type silicate sample, as a function of temperature, is investigated and an activation energy for crystallization is determined. The obtained value of {E_a}/k = 41 700 ± 2400 K is in good agreement with previous determinations of the activation energies of crystallization reported for non-ion-irradiated, amorphous silicates. This implies that the crystallization process is independent of the history of the dust. In particular, the defect concentration due to irradiation appears not to play a major role in stimulating, or hindering, crystallization at a given temperature. This activation energy is an important thermodynamical parameter that must be used in theoretical models which aim to explain the dust evolution from its place of birth in late type stars to its incorporation into young stellar environments, proto-stellar discs and proto-planetary systems after long passage through the interstellar medium.

  11. Surface free energy activated high-throughput cell sorting.

    PubMed

    Zhang, Xinru; Zhang, Qian; Yan, Tao; Jiang, Zeyi; Zhang, Xinxin; Zuo, Yi Y

    2014-09-16

    Cell sorting is an important screening process in microbiology, biotechnology, and clinical research. Existing methods are mainly based on single-cell analysis as in flow cytometric and microfluidic cell sorters. Here we report a label-free bulk method for sorting cells by differentiating their characteristic surface free energies (SFEs). We demonstrated the feasibility of this method by sorting model binary cell mixtures of various bacterial species, including Pseudomonas putida KT2440, Enterococcus faecalis ATCC 29212, Salmonella Typhimurium ATCC 14028, and Escherichia coli DH5α. This method can effectively separate 10(10) bacterial cells within 30 min. Individual bacterial species can be sorted with up to 96% efficiency, and the cell viability ratio can be as high as 99%. In addition to its capacity of sorting evenly mixed bacterial cells, we demonstrated the feasibility of this method in selecting and enriching cells of minor populations in the mixture (presenting at only 1% in quantity) to a purity as high as 99%. This SFE-activated method may be used as a stand-alone method for quickly sorting a large quantity of bacterial cells or as a prescreening tool for microbial discrimination. Given its advantages of label-free, high-throughput, low cost, and simplicity, this SFE-activated cell sorting method has potential in various applications of sorting cells and abiotic particles.

  12. Energy-efficiency testing activities of the Mobile Energy Laboratory - Semiannual Report: April 1, 1990, Through September 30, 1990

    SciTech Connect

    Parker, G.B.; Currie, J.W.

    1991-03-01

    This report summarizes energy-efficiency testing activities applying the Mobile Energy Laboratory (MEL) testing capabilities during the third and fourth quarters of fiscal year (FY) 1990. The MELs, developed by the US Department of Energy (DOE) Federal Energy Management Program (FEMP), are administered by Pacific Northwest Laboratory (PNL) and the Naval Energy and Environmental Support Activity (NEESA) for energy testing and energy conservation program support functions at federal facilities. MELs are equipped for the on-site evaluation of energy use efficiency. The using agencies principally fund MEL applications, while DOE/FEMP funds program administration and capability enhancement activities. This report fulfills the requirements established in Section 8 of the MEL Use Plan (PNL-6861) for semiannual reporting on energy-efficiency testing activities using the MEL capabilities. The MEL Use Committee, formally established in 1989, developed the MEL Use Plan and meets semiannually to establish priorities for energy-efficient testing applications using the MEL capabilities. This report describes the testing, test results, and suggested courses of action.

  13. Enhanced photocatalytic activity of TiO2-impregnated with MgZnAl mixed oxides obtained from layered double hydroxides for phenol degradation

    NASA Astrophysics Data System (ADS)

    de Almeida, Marciano Fabiano; Bellato, Carlos Roberto; Mounteer, Ann Honor; Ferreira, Sukarno Olavo; Milagres, Jaderson Lopes; Miranda, Liany Divina Lima

    2015-12-01

    A series of TiO2/MgZnAl photocatalysts were successfully synthesized from ternary (Mg, Zn and Al) layered double hydroxides impregnated with TiO2 nanoparticles by the co-precipitation method at variable pH with different Zn2+/Mg2+ molar ratios. The composite photocatalysts were calcined at 500 °C resulting in the incorporation of oxide zinc, in the calcined MgZnAl LDH structure. Synergistic effect between ZnO and TiO2 lead to significant enhancement of TiO2/MgZnAl photocatalytic activity. Composite photocatalysts were characterized by ICP-MS, N2 adsorption-desorption, XRD, SEM, EDS, IR and UV-vis DRS. Phenol in aqueous solution (50 mg/L) was used as a model compound for evaluation of UV-vis (filter cut-off for λ > 300 nm) photocatalytic activity. The most efficient photocatalyst composite was obtained at a 5% Zn2+/Mg2+ molar ratio, in the catalyst identified as TiO2/MgZnAl-5. This composite catalyst had high photocatalytic activity, completely destroying phenol and removing 80% of total organic carbon in solution after 360 min. The TiO2/MgZnAl-5 catalyst remained relatively stable, presenting a 15% decrease in phenol degradation efficiency after five consecutive photocatalytic cycles.

  14. Effect of the incorporation of chitosan on the physico-chemical, mechanical properties and biological activity on a mixture of polycaprolactone and polyurethanes obtained from castor oil.

    PubMed

    Arévalo, Fabian; Uscategui, Yomaira L; Diaz, Luis; Cobo, Martha; Valero, Manuel F

    2016-11-01

    In the present study, polyurethane materials were obtained from castor oil, polycaprolactone and isophorone diisocyanate by incorporating different concentrations of chitosan (0.5, 1.0 and 2.0% w/w) as an additive to improve the mechanical properties and the biological activity of polyurethanes. The polyurethanes were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, stress/strain fracture tests and swelling analysis, and the hydrophilic character of the surface was determined by contact angle trials. The objectives of the study were to evaluate the effect of the incorporation of chitosan on the changes of the physico-chemical and mechanical properties and the in vitro biological activity of the polyurethanes. It was found that the incorporation of chitosan enhances the ultimate tensile strength of the polyurethanes and does not affect the strain at fracture in polyurethanes with 5% w/w of polycaprolactone and concentrations of chitosan ranging from 0 to 2% w/w. In addition, PCL5-Q-PU formulations and their degradation products did not affect cell viability of L929 mouse fibroblast and 3T3, respectively. Polyurethane formulations showed antibacterial activities against Staphylococcus aureus and Escherichia coli bacteria. The results of this study have highlighted the potential biomedical application of this polyurethanes related to soft and cardiovascular tissues.

  15. Activity Profile and Energy Expenditure Among Active Older Adults, British Columbia, 2011–2012

    PubMed Central

    Ashe, Maureen C.; Chase, Jocelyn M.

    2015-01-01

    Introduction Time spent by young adults in moderate to vigorous activity predicts daily caloric expenditure. In contrast, caloric expenditure among older adults is best predicted by time spent in light activity. We examined highly active older adults to examine the biggest contributors to energy expenditure in this population. Methods Fifty-four community-dwelling men and women aged 65 years or older (mean, 71.4 y) were enrolled in this cross-sectional observational study. All were members of the Whistler Senior Ski Team, and all met current American guidelines for physical activity. Activity levels (sedentary, light, and moderate to vigorous) were recorded by accelerometers worn continuously for 7 days. Caloric expenditure was measured using accelerometry, galvanic skin response, skin temperature, and heat flux. Significant variables were entered into a stepwise multivariate linear model consisting of activity level, age, and sex. Results The average (standard deviation [SD]) daily nonlying sedentary time was 564 (92) minutes (9.4 [1.5] h) per day. The main predictors of higher caloric expenditure were time spent in moderate to vigorous activity (standardized β = 0.42 [SE, 0.08]; P < .001) and male sex (standardized β = 1.34 [SE, 0.16]; P < .001). A model consisting of only moderate to vigorous physical activity and sex explained 68% of the variation in caloric expenditure. An increase in moderate to vigorous physical activity by 1 minute per day was associated with an additional 16 kcal expended in physical activity. Conclusion The relationship between activity intensity and caloric expenditure in athletic seniors is similar to that observed in young adults. Active older adults still spend a substantial proportion of the day engaged in sedentary behaviors. PMID:26182147

  16. Solar energy in Australia: a profile of renewable energy activity in its national context

    SciTech Connect

    Case, G.L.

    1980-08-01

    The following topics are included: country overview; energy summary; geopolitical, economic, and cultural aspects of Australia; the energy profile; and international agreements, contacts, manufacturers, and projects. (MHR)

  17. Results of the 2016 UT modeling benchmark proposed by the French Atomic Energy Commission (CEA) obtained with models implemented in CIVA software

    NASA Astrophysics Data System (ADS)

    Toullelan, Gwénaël; Chatillon, Sylvain; Raillon, Raphaële; Mahaut, Steve; Lonné, Sébastien; Bannouf, Souad

    2017-02-01

    For several years, the World Federation of NDE Centers, WFNDEC, proposes benchmark studies in which simulated results (in either ultrasonic, X-rays or eddy current NDT configurations) obtained with various models are compared to experiments. This year the proposed UT benchmark proposed by CEA concerns inspection configurations with multi-skips echoes i.e. the incident beam undergoes several skips on the surface and bottom of the specimen before interacting with the defect. This technique is commonly used to inspect thin specimen and/or in case of limited access inspection. This technique relies on the use of T45° mode in order to avoid mode conversion and to facilitate the interpretation of the echoes. The inspections were carried out with two probes of different aperture working at 5MHz.

  18. Activity related energy expenditure, appetite and energy intake: potential implications for weight management.

    PubMed

    Harrington, D M; Martin, C K; Ravussin, E; Katzmarzyk, P T

    2013-08-01

    The aim was to investigate relationships between activity related energy expenditure (AREE), appetite ratings and energy intake (EI) in a sample of 40 male (26.4years; BMI 23.5kg/m(2)) and 42 female (26.9years; BMI 22.4kg/m(2)) participants. AREE was expressed as the residual value of the regression between total daily EE (by doubly labeled water) and resting EE (by indirect calorimetry). EI was measured using an ad libitum buffet meal and visual analogue scales measured subjective appetite ratings before and after the meal. AREE was divided into low, middle and high sex-specific tertiles. General linear models were used to investigate differences in appetite ratings and EI across AREE tertiles. Before the meal, males in the high AREE tertile had significantly lower desire to eat and lower prospective food consumption and higher feelings of fullness compared to those in the low tertile. Males in the middle tertile had significantly higher satiety quotients after the meal and lower EI compared to the other tertiles. No significant differences across tertiles were found in females. Sex differences in relationships between AREE, appetite ratings and EI may lead to differing patterns of EI and subsequent weight maintenance.

  19. In vitro antifungal activity of extracts obtained from Hypericum perforatum adventitious roots cultured in a mist bioreactor against planktonic cells and biofilm of Malassezia furfur.

    PubMed

    Simonetti, Giovanna; Tocci, Noemi; Valletta, Alessio; Brasili, Elisa; D'Auria, Felicia Diodata; Idoux, Alicia; Pasqua, Gabriella

    2016-01-01

    Xanthone-rich extracts from Hypericum perforatum root cultures grown in a Mist Bioreactor as antifungal agents against Malassezia furfur. Extracts of Hypericum perforatum roots grown in a bioreactor showed activity against planktonic cells and biofilm of Malassezia furfur. Dried biomass, obtained from roots grown under controlled conditions in a ROOTec mist bioreactor, has been extracted with solvents of increasing polarity (i.e. chloroform, ethyl acetate and methanol). The methanolic fraction was the richest in xanthones (2.86 ± 0.43 mg g(-1) DW) as revealed by HPLC. The minimal inhibitory concentration of the methanol extract against M. furfur planktonic cells was 16 μg mL(-1). The inhibition percentage of biofilm formation, at a concentration of 16 μg mL(-1), ranged from 14% to 39%. The results show that H. perforatum root extracts could be used as new antifungal agents in the treatment of Malassezia infections.

  20. Homogeneous near surface activity distribution by double energy activation for TLA

    NASA Astrophysics Data System (ADS)

    Takács, S.; Ditrói, F.; Tárkányi, F.

    2007-10-01

    Thin layer activation (TLA) is a versatile tool for activating thin surface layers in order to study real-time the surface loss by wear, corrosion or erosion processes of the activated parts, without disassembling or stopping running mechanical structures or equipment. The research problem is the determination of the irradiation parameters to produce point-like or large area optimal activity-depth distribution in the sample. Different activity-depth profiles can be produced depending on the type of the investigated material and the nuclear reaction used. To produce activity that is independent of the depth up to a certain depth is desirable when the material removed from the surface by wear, corrosion or erosion can be collected completely. By applying dual energy irradiation the thickness of this quasi-constant activity layer can be increased or the deviation of the activity distribution from a constant value can be minimized. In the main, parts made of metals and alloys are suitable for direct activation, but by using secondary particle implantation the wear of other materials can also be studied in a surface range a few micrometers thick. In most practical cases activation of a point-like spot (several mm2) is enough to monitor the wear, corrosion or erosion, but for special problems relatively large surfaces areas of complicated spatial geometry need to be activated uniformly. Two ways are available for fulfilling this task, (1) production of large area beam spot or scanning the beam over the surface in question from the accelerator side, or (2) a programmed 3D movement of the sample from the target side. Taking into account the large variability of tasks occurring in practice, the latter method was chosen as the routine solution in our cyclotron laboratory.

  1. Free energy profiles for penetration of methane and water molecules into spherical sodium dodecyl sulfate micelles obtained using the thermodynamic integration method combined with molecular dynamics calculations

    NASA Astrophysics Data System (ADS)

    Fujimoto, K.; Yoshii, N.; Okazaki, S.

    2012-01-01

    The free energy profiles, ΔG(r), for penetration of methane and water molecules into sodium dodecyl sulfate (SDS) micelles have been calculated as a function of distance r from the SDS micelle to the methane and water molecules, using the thermodynamic integration method combined with molecular dynamics calculations. The calculations showed that methane is about 6-12 kJ mol-1 more stable in the SDS micelle than in the water phase, and no ΔG(r) barrier is observed in the vicinity of the sulfate ions of the SDS micelle, implying that methane is easily drawn into the SDS micelle. Based on analysis of the contributions from hydrophobic groups, sulfate ions, sodium ions, and solvent water to ΔG(r), it is clear that methane in the SDS micelle is about 25 kJ mol-1 more stable than it is in the water phase because of the contribution from the solvent water itself. This can be understood by the hydrophobic effect. In contrast, methane is destabilized by 5-15 kJ mol-1 by the contribution from the hydrophobic groups of the SDS micelle because of the repulsive interactions between the methane and the crowded hydrophobic groups of the SDS. The large stabilizing effect of the solvent water is higher than the repulsion by the hydrophobic groups, driving methane to become solubilized into the SDS micelle. A good correlation was found between the distribution of cavities and the distribution of methane molecules in the micelle. The methane may move about in the SDS micelle by diffusing between cavities. In contrast, with respect to the water, ΔG(r) has a large positive value of 24-35 kJ mol-1, so water is not stabilized in the micelle. Analysis showed that the contributions change in complex ways as a function of r and cancel each other out. Reference calculations of the mean forces on a penetrating water molecule into a dodecane droplet clearly showed the same free energy behavior. The common feature is that water is less stable in the hydrophobic core than in the water phase

  2. Energy and Safety: Science Activities for Elementary Students, Level III (Grades (5-6).

    ERIC Educational Resources Information Center

    Westcott, Dale; And Others

    Thirteen activities are presented that focus on a common phenomenon of a child's world: energy. These activities relate energy, how it occurs, how it is used, and how to use it safely. Each activity includes the purpose, introduction, background, procedure, materials, estimated time for the activity, typical results, safety notes, and more ideas.…

  3. Industrial Technology. Iowa Developed Energy Activity Sampler, 6-12. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This document is one of the series of revised IDEAS booklets, and provides activities for teaching industrial arts/technology education. The activities are intended to present energy…

  4. Energy and Safety: Science Activities for Elementary Students, Level II (Grades (3-4).

    ERIC Educational Resources Information Center

    Westcott, Dale; And Others

    Thirteen activities are presented that focus on a common phenomenon of a child's world: energy. These activities relate energy, how it occurs, how it is used, and how to use it safely. Each activity includes the purpose, introduction, background, procedure, materials, estimated time for the activity, typical results, safety notes, and more ideas.…

  5. Growth inhibitory activities of crude extracts obtained from herbal plants in the Ryukyu Islands on several human colon carcinoma cell lines.

    PubMed

    Kaneshiro, Tatsuya; Suzui, Masumi; Takamatsu, Reika; Murakami, Akira; Ohigashi, Hajime; Fujino, Tetsuya; Yoshimi, Naoki

    2005-01-01

    There is increasing interest in the use of herbs for the treatment of human diseases including cancer. Therefore, the purpose of this study was to determine whether crude extracts obtained from 44 herbal plants in the Ryukyu Islands might contain components capable of inhibiting the growth of a variety of human colon carcinoma cell lines. Leaves, roots and other parts of the plants were extracted with chloroform, and the crude extracts were dissolved in dimethylsulfoxide and used for the experiments. Extracts of Hemerocallis fulva, Ipomoea batatas, Curcuma longa, and Nasturium officinale caused marked dose-dependent growth inhibition, with IC(50) values in the range of 10-80 mug/ml. With the HCT116 cell line, the extracts of Hemerocallis fulva and Ipomoea batatas induced G1 cell cycle arrest after 48 h of treatment. In addition, we found that extracts of Curcuma longa, and Nasturium officinale induced apoptosis in these cells after 48 h of treatment. The present studies are the first systematic examination of the growth inhibitory effects of crude extracts obtained from herbal plants in the Ryukyu Islands. The findings provide evidence that several plants in the Ryukyu Islands contain components that may have anticancer activity.

  6. Proposal and design of a natural gas liquefaction process recovering the energy obtained from the pressure reducing stations of high-pressure pipelines

    NASA Astrophysics Data System (ADS)

    Tan, Hongbo; Zhao, Qingxuan; Sun, Nannan; Li, Yanzhong

    2016-12-01

    Taking advantage of the refrigerating effect in the expansion at an appropriate temperature, a fraction of high-pressure natural gas transported by pipelines could be liquefied in a city gate station through a well-organized pressure reducing process without consuming any extra energy. The authors proposed such a new process, which mainly consists of a turbo-expander driven booster, throttle valves, multi-stream heat exchangers and separators, to yield liquefied natural gas (LNG) and liquid light hydrocarbons (LLHs) utilizing the high-pressure of the pipelines. Based on the assessment of the effects of several key parameters on the system performance by a steady-state simulation in Aspen HYSYS, an optimal design condition of the proposed process was determined. The results showed that the new process is more appropriate to be applied in a pressure reducing station (PRS) for the pipelines with higher pressure. For the feed gas at the pressure of 10 MPa, the maximum total liquefaction rate (ytot) of 15.4% and the maximum exergy utilizing rate (EUR) of 21.7% could be reached at the optimal condition. The present process could be used as a small-scale natural gas liquefying and peak-shaving plant at a city gate station.

  7. The effect of a broad activation energy distribution on deuteron spin-lattice relaxation.

    PubMed

    Ylinen, E E; Punkkinen, M; Birczyński, A; Lalowicz, Z T

    2015-10-01

    Deuteron NMR spectra and spin-lattice relaxation were studied experimentally in zeolite NaY(2.4) samples containing 100% or 200% of CD3OH or CD3OD molecules of the total coverage of Na atoms in the temperature range 20-150K. The activation energies describing the methyl and hydroxyl motions show broad distributions. The relaxation data were interpreted by improving a recent model (Stoch et al., 2013 [16]) in which the nonexponential relaxation curves are at first described by a sum of three exponentials with adjustable relaxation rates and weights. Then a broad distribution of activation energies (the mean activation energy A0 and the width σ) was assumed for each essentially different methyl and hydroxyl position. The correlation times were calculated from the Arrhenius equation (containing the pre-exponential factor τ0), individual relaxation rates computed and classified into three classes, and finally initial relaxation rates and weights for each class formed. These were compared with experimental data, motional parameters changed slightly and new improved rates and weights for each class calculated, etc. This method was improved by deriving for the deuterons of the A and E species methyl groups relaxation rates, which depend explicitly on the tunnel frequency ωt. The temperature dependence of ωt and of the low-temperature correlation time were obtained by using the solutions of the Mathieu equation for a threefold potential. These dependencies were included in the simulations and as the result sets of A0, σ and τ0 obtained, which describe the methyl and hydroxyl motions in different positions in zeolite.

  8. Influence of Polarity and Activation Energy in Microwave-Assisted Organic Synthesis (MAOS).

    PubMed

    Rodríguez, Antonio M; Prieto, Pilar; de la Hoz, Antonio; Díaz-Ortiz, Ángel; Martín, D Raúl; García, José I

    2015-06-01

    The aim of this work was to determine the parameters that have decisive roles in microwave-assisted reactions and to develop a model, using computational chemistry, to predict a priori the type of reactions that can be improved under microwaves. For this purpose, a computational study was carried out on a variety of reactions, which have been reported to be improved under microwave irradiation. This comprises six types of reactions. The outcomes obtained in this study indicate that the most influential parameters are activation energy, enthalpy, and the polarity of all the species that participate. In addition to this, in most cases, slower reacting systems observe a much greater improvement under microwave irradiation. Furthermore, for these reactions, the presence of a polar component in the reaction (solvent, reagent, susceptor, etc.) is necessary for strong coupling with the electromagnetic radiation. We also quantified that an activation energy of 20-30 kcal mol(-1) and a polarity (μ) between 7-20 D of the species involved in the process is required to obtain significant improvements under microwave irradiation.

  9. Influence of Polarity and Activation Energy in Microwave–Assisted Organic Synthesis (MAOS)

    PubMed Central

    Rodríguez, Antonio M; Prieto, Pilar; de la Hoz, Antonio; Díaz-Ortiz, Ángel; Martín, D Raúl; García, José I

    2015-01-01

    The aim of this work was to determine the parameters that have decisive roles in microwave-assisted reactions and to develop a model, using computational chemistry, to predict a priori the type of reactions that can be improved under microwaves. For this purpose, a computational study was carried out on a variety of reactions, which have been reported to be improved under microwave irradiation. This comprises six types of reactions. The outcomes obtained in this study indicate that the most influential parameters are activation energy, enthalpy, and the polarity of all the species that participate. In addition to this, in most cases, slower reacting systems observe a much greater improvement under microwave irradiation. Furthermore, for these reactions, the presence of a polar component in the reaction (solvent, reagent, susceptor, etc.) is necessary for strong coupling with the electromagnetic radiation. We also quantified that an activation energy of 20–30 kcal mol−1 and a polarity (μ) between 7–20 D of the species involved in the process is required to obtain significant improvements under microwave irradiation. PMID:26246993

  10. Solar energy in Italy: A profile of renewable energy activity in its national context

    NASA Astrophysics Data System (ADS)

    Shea, C. A.

    1980-12-01

    The energy profile includes: imported energy sources; solar research and development; solar energy organizations; solar energy related legislation and administration policies; and international agreements, contacts, manufacturers, and projects. The country overview includes: Italian Republic geopolitical analysis; economic analysis; and cultural aspects.

  11. Self-Directed Weight Loss Strategies: Energy Expenditure Due to Physical Activity Is Not Increased to Achieve Intended Weight Loss

    PubMed Central

    Elbelt, Ulf; Schuetz, Tatjana; Knoll, Nina; Burkert, Silke

    2015-01-01

    Reduced physical activity and almost unlimited availability of food are major contributors to the development of obesity. With the decline of strenuous work, energy expenditure due to spontaneous physical activity has attracted increasing attention. Our aim was to assess changes in energy expenditure, physical activity patterns and nutritional habits in obese subjects aiming at self-directed weight loss. Methods: Energy expenditure and physical activity patterns were measured with a portable armband device. Nutritional habits were assessed with a food frequency questionnaire. Results: Data on weight development, energy expenditure, physical activity patterns and nutritional habits were obtained for 105 patients over a six-month period from an initial cohort of 160 outpatients aiming at weight loss. Mean weight loss was −1.5 ± 7.0 kg (p = 0.028). Patients with weight maintenance (n = 75), with substantial weight loss (>5% body weight, n = 20) and with substantial weight gain (>5% body weight, n = 10) did not differ in regard to changes of body weight adjusted energy expenditure components (total energy expenditure: −0.2 kcal/kg/day; non-exercise activity thermogenesis: −0.3 kcal/kg/day; exercise-related activity thermogenesis (EAT): −0.2 kcal/kg/day) or patterns of physical activity (duration of EAT: −2 min/day; steps/day: −156; metabolic equivalent unchanged) measured objectively with a portable armband device. Self-reported consumption frequency of unfavorable food decreased significantly (p = 0.019) over the six-month period. Conclusions: An increase in energy expenditure or changes of physical activity patterns (objectively assessed with a portable armband device) are not employed by obese subjects to achieve self-directed weight loss. However, modified nutritional habits could be detected with the use of a food frequency questionnaire. PMID:26193310

  12. Anti-inflammatory activity of the essential oil obtained from Ocimum basilicum complexed with β-cyclodextrin (β-CD) in mice.

    PubMed

    Rodrigues, Lindaiane Bezerra; Martins, Anita Oliveira Brito Pereira Bezerra; Ribeiro-Filho, Jaime; Cesário, Francisco Rafael Alves Santana; E Castro, Fyama Ferreira; de Albuquerque, Thaís Rodrigues; Fernandes, Maria Neyze Martins; da Silva, Bruno Anderson Fernandes; Quintans Júnior, Lucindo José; Araújo, Adriano Antunes de Sousa; Menezes, Paula Dos Passos; Nunes, Paula Santos; Matos, Isabella Gonçalves; Coutinho, Henrique Douglas Melo; Goncalves Wanderley, Almir; de Menezes, Irwin Rose Alencar

    2017-02-22

    Cyclodextrins (CDs) are cyclic oligosaccharides can enhance the bioavailability of drugs. Ocimum basilicum is an aromatic plant found in Brazil used in culinary. The essential oil of this plant presents anti-edematogenic and anti-inflammatory activities in acute and chronic inflammation. The aim of this study was to investigate the anti-inflammatory effects of the essential oil obtained from O. basilicum complexed with β - cyclodextrin (OBEO/β-CD) in mice. The complexation with β-cyclodextrin (β-CD) was performed by different methods and analyzed by differential scanning calorimetry (DSC), thermogravimetry (TG) and scanning electron microscopy (SEM). The anti-inflammatory activity was evaluated using mice models of paw edema induced by carrageenan, dextran, histamine and arachidonic acid (AA); vascular permeability and peritonitis induced by carrageenan and granuloma induced by cotton block introduction. The DSC, TG and SEM analysis indicated that the OBEO was successfully complexed with β-CD. The oral administration of OEOB/β-CD prevented paw edema formation by decreasing vascular permeability in vivo, inhibited leukocyte recruitment to the peritoneal cavity, and inhibited granuloma formation in mice. Our results indicate that conjugation with β-CD improves the anti-inflammatory effects of OBEO in mice models of acute and chronic inflammation, indicating that this complex can be used in anti-inflammatory drug development.

  13. High energy neutrinos from radio-quiet active galactic nuclei

    NASA Astrophysics Data System (ADS)

    Alvarez-Muñiz, Jaime; Mészáros, Peter

    2004-12-01

    Most active galactic nuclei (AGN) lack prominent jets, and show modest radio emission and significant x-ray emission which arises mainly from the galactic core, very near the central black hole. We use a quantitative scenario of such core-dominated radio-quiet AGN, which attributes a substantial fraction of the x-ray emission to the presence of abortive jets involving the collision of gas blobs in the core. Here we investigate the consequences of the acceleration of protons in the shocks from such collisions. We find that protons will be accelerated up to energies above the pion photoproduction threshold on both the x rays and the UV photons from the accretion disk. The secondary charged pions decay, producing neutrinos. We predict significant fluxes of TeV-PeV neutrinos, and show that the AMANDA II detector is already constraining several important astrophysical parameters of these sources. Larger cubic kilometer detectors such as IceCube will be able to detect such neutrinos in less than one year of operation, or otherwise rule out this scenario.

  14. Calculating activation energies for temperature compensation in circadian rhythms

    NASA Astrophysics Data System (ADS)

    Bodenstein, C.; Heiland, I.; Schuster, S.

    2011-10-01

    Many biological species possess a circadian clock, which helps them anticipate daily variations in the environment. In the absence of external stimuli, the rhythm persists autonomously with a period of approximately 24 h. However, single pulses of light, nutrients, chemicals or temperature can shift the clock phase. In the case of light- and temperature-cycles, this allows entrainment of the clock to cycles of exactly 24 h. Circadian clocks have the remarkable property of temperature compensation, that is, the period of the circadian rhythm remains relatively constant within a physiological range of temperatures. For several organisms, temperature-regulated processes within the circadian clock have been identified in recent years. However, how these processes contribute to temperature compensation is not fully understood. Here, we theoretically investigate temperature compensation in general oscillatory systems. It is known that every oscillator can be locally temperature compensated around a reference temperature, if reactions are appropriately balanced. A balancing is always possible if the control coefficient with respect to the oscillation period of at least one reaction in the oscillator network is positive. However, for global temperature compensation, the whole physiological temperature range is relevant. Here, we use an approach which leads to an optimization problem subject to the local balancing principle. We use this approach to analyse different circadian clock models proposed in the literature and calculate activation energies that lead to temperature compensation.

  15. Activation energy of methyl radical decay in methane hydrate.

    PubMed

    Takeya, Kei; Nango, Kouhei; Sugahara, Takeshi; Ohgaki, Kazunari; Tani, Atsushi

    2005-11-10

    The thermal stability of gamma-ray-induced methyl radicals in methane hydrate was studied using the ESR method at atmospheric pressure and 210-260 K. The methyl radical decay proceeded with the second-order reaction, and ethane molecules were generated from the dimerization process. The methyl radical decay proceeds by two different temperature-dependent processes, that is, the respective activation energies of these processes are 20.0 +/- 1.6 kJ/mol for the lower temperature region of 210-230 K and 54.8 +/- 5.7 kJ/mol for the higher temperature region of 235-260 K. The former agrees well with the enthalpy change of methane hydrate dissociation into ice and gaseous methane, while the latter agrees well with the enthalpy change into liquid water and gaseous methane. The present findings reveal that methane hydrates dissociate into liquid (supercooled) water and gaseous methane in the temperature range of 235-260 K.

  16. INVESTIGATION OF HELICITY AND ENERGY FLUX TRANSPORT IN THREE EMERGING SOLAR ACTIVE REGIONS

    SciTech Connect

    Vemareddy, P.

    2015-06-20

    We report the results of an investigation of helicity and energy flux transport from three emerging solar active regions (ARs). Using time sequence vector magnetic field observations obtained from the Helioseismic Magnetic Imager, the velocity field of plasma flows is derived by the differential affine velocity estimator for vector magnetograms. In three cases, the magnetic fluxes evolve to pump net positive, negative, and mixed-sign helicity flux into the corona. The coronal helicity flux is dominantly coming from the shear term that is related to horizontal flux motions, whereas energy flux is dominantly contributed by the emergence term. The shear helicity flux has a phase delay of 5–14 hr with respect to absolute magnetic flux. The nonlinear curve of coronal energy versus relative helicity identifies the configuration of coronal magnetic fields, which is approximated by a fit of linear force-free fields. The nature of coronal helicity related to the particular pattern of evolving magnetic fluxes at the photosphere has implications for the generation mechanism of two kinds of observed activity in the ARs.

  17. Communication: Activation energy of tension-induced pore formation in lipid membranes.

    PubMed

    Karal, Mohammad Abu Sayem; Yamazaki, Masahito

    2015-08-28

    Tension plays a vital role in pore formation in biomembranes, but the mechanism of pore formation remains unclear. We investigated the temperature dependence of the rate constant of constant tension (σ)-induced pore formation in giant unilamellar vesicles of lipid membranes using an experimental method we developed. By analyzing this result, we determined the activation energy (Ua) of tension-induced pore formation as a function of tension. A constant (U0) that does not depend on tension was found to contribute significantly to Ua. Analysis of the activation energy clearly indicated that the dependence of Ua on σ in the classical theory is correct, but that the classical theory of pore formation is not entirely correct due to the presence of U0. We can reasonably consider that U0 is a nucleation free energy to form a hydrophilic pre-pore from a hydrophobic pre-pore or a region with lower lateral lipid density. After obtaining U0, the evolution of a pre-pore follows a classical theory. Our data provide valuable information that help explain the mechanism of tension-induced pore formation in biomembranes and lipid membranes.

  18. Some New Observations on Activation Energy of Crystal Growth for Thermally Activated Crystallization.

    PubMed

    Mehta, N; Kumar, A

    2016-02-18

    Calorimetric study of glass/crystal phase transformation in disordered semiconductors is a significant tool for understanding their crystallization kinetics. Such studies provide the basis for practical application of glasses. Differential scanning calorimetry (DSC) is one of the advanced techniques for the analysis of thermally induced crystallization in glassy or amorphous systems. We are reporting the nonisothermal DSC measurements on four amorphous systems of Se70Te30 alloy with Ag, Cd, Sb, and Zn as chemical modifiers. In general, the rate constant (K) shows Arrhenian dependence on temperature (T), i.e., K = K0 exp (-Eg/RT) where Eg is the activation energy of crystal growth and K0 is called the pre-exponential factor of rate constant. In the present work, an experiment is designed to see the effect of composition on the activation energy of crystal growth. We have found Meyer-Neldel relation (MNR) between Eg and K0 for present systems. Another interesting feature of present work is the observation of further relation between Meyer-Neldel prefactor and Meyer-Neldel energy.

  19. Disturbance observer based active and adaptive synchronization of energy resource chaotic system.

    PubMed

    Wei, Wei; Wang, Meng; Li, Donghai; Zuo, Min; Wang, Xiaoyi

    2016-11-01

    In this paper, synchronization of a three-dimensional energy resource chaotic system is considered. For the sake of achieving the synchronization between the drive and response systems, two different nonlinear control approaches, i.e. active control with known parameters and adaptive control with unknown parameters, have been designed. In order to guarantee the transient performance, finite-time boundedness (FTB) and finite-time stability (FTS) are introduced in the design of active control and adaptive control, respectively. Simultaneously, in view of the existence of disturbances, a new disturbance observer is proposed to estimate the disturbance. The conditions of the asymptotic stability for the closed-loop system are obtained. Numerical simulations are provided to illustrate the proposed approaches.

  20. Energy monitoring based on human activity in the workplace

    NASA Astrophysics Data System (ADS)

    Mustafa, N. H.; Husain, M. N.; Abd Aziz, M. Z. A.; Othman, M. A.; Malek, F.

    2014-04-01

    Human behavior is the most important factor in order to manage energy usage. Nowadays, smart house technology offers a better quality of life by introducing automated appliance control and assistive services. However, human behaviors will contribute to the efficiency of the system. This paper will focus on monitoring efficiency based on duration time in office hours around 8am until 5pm which depend on human behavior atb the workplace. Then, the correlation coefficient method is used to show the relation between energy consumption and energy saving based on the total hours of time energy spent. In future, the percentages of energy monitoring system usage will be increase to manage energy in efficient ways based on human behaviours. This scenario will lead to the positive impact in order to achieve the energy saving in the building and support the green environment.

  1. 77 FR 46089 - Agency Information Collection Activities; Proposed Collection; Comment Request; EPA's ENERGY STAR...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-02

    ... Information Collection Activities; Proposed Collection; Comment Request; EPA's ENERGY STAR Program in the... this action are participants in EPA's ENERGY STAR Program in the Commercial and Industrial Sectors. Title: Information Collection Activities Associated with EPA's ENERGY STAR Program in the Commercial...

  2. K.E.E.P. - Kentucky's Energy Education Program Activities for the Classroom, 7-12.

    ERIC Educational Resources Information Center

    Theiss, Nancy Stearns, Ed.; And Others

    Seventy-four multidisciplinary activities for grades seven through twelve are contained in this revised edition of energy education lessons for Kentucky students. Section I helps students understand energy and the current crisis by studying laws which govern energy flow and using examples of how these laws illustrate stable energy utilization…

  3. Energy in the Classroom, Vol. I, Activities Guide for K-3.

    ERIC Educational Resources Information Center

    Erickson, Kathy Baker; Sherman, Deborah Fick

    This booklet is a teacher's guide for teaching about energy, types of energy, sources of energy, and ways to conserve energy. It is designed for students in grades K-3. Included are a variety of activities, sheets that can be copied for handouts, and a bibliography of student references. (RH)

  4. Energy in the Classroom, Vol. II, Activities Guide for 4-7.

    ERIC Educational Resources Information Center

    Erickson, Kathy Baker; Sherman, Deborah Fick

    This booklet is a teacher's guide for teaching about energy, types of energy, sources of energy, and ways to conserve energy. It is designed for students in grades 4-7. Included are a variety of activities, sheets that can be copied for handouts, and a bibliography of student references. (RH)

  5. K.E.E.P. - Kentucky's Energy Education Program Activities for the Classroom, K-6.

    ERIC Educational Resources Information Center

    Theiss, Nancy Stearns, Ed.; And Others

    Seventy-seven multidisciplinary activities for grades K-6 are contained in this revised edition of energy education lessons for Kentucky students. Section I introduces students to the topic of energy by emphasizing human interaction with the environment. It focuses on personal energy, food as the source of human energy, food chains, and the sun as…

  6. Surface-enhanced Raman imaging of red blood cell membrane with highly uniform active substrates obtained using block copolymers self-assembly

    NASA Astrophysics Data System (ADS)

    Zito, Gianluigi; Malafronte, Anna; Dochshanov, Alden; Rusciano, Giulia; Auriemma, Finizia; Pesce, Giuseppe; De Rosa, Claudio; Sasso, Antonio

    2013-05-01

    In this communication, we discuss the application of ordered, ultrahigh-density templates of nano-textured Ag-particles obtained by self-assembling of inorganic-containing polystyrene-block-poly(4-vinylpyridine) copolymer (PS-b-P4VP) micelles, for the spectroscopic surface-enhanced Raman imaging in-vitro of red blood cells (RBCs) and its capability to identify the vibrational fingerprint of the plasma membrane of the cell physisorbed to the SERS substrate. Hexagonal arrays of PS-b-P4VP micelles, with selective inclusion of Ag nanoparticles (NPs) in the polar core, prepared by in situ reduction of a suitable precursor, are obtained by polymer self-assembly upon fast solvent evaporation during spin coating on the supporting substrate. UV irradiation and/or plasma oxygen treatment remove the polymer matrix leaving immobilized nano-islands of Ag-NPs. Such a kind of SERS-active substrate consists of a reproducible and uniform twodimensional hexagonal array of silver clusters with a diameter ranging from 25 to 30 nm (single particles having typically diameters of 5 nm) and nano-island gap distances of the order of 5-8 nm on silicon and 15 nm on glass , while giving rise to high enhancement factors and addressing the issue of SERS reproducibility. The basic substrate supporting the plasmonic coating used in this work is either of silicon or glass. This last allows working in back scattering configuration permitting real time monitoring, via microscopy, of the RBCs on which Raman measurements are being carried out. The template is thus applied for surface-enhanced Raman analysis of the red blood cell (RBC) membrane in confocal micro-Raman configuration demonstrating to have SERS imaging potential thanks to the uniformity of the nano-textured substrate. The first experimental evidence of SERS imaging of a red blood cell membrane in-vitro is demonstrated.

  7. Is a Coded Physical Activity Diary Valid for Assessing Physical Activity Level and Energy Expenditure in Stroke Patients?

    PubMed Central

    Vanroy, Christel; Vanlandewijck, Yves; Cras, Patrick; Feys, Hilde; Truijen, Steven; Michielsen, Marc; Vissers, Dirk

    2014-01-01

    Objectives to determine the concurrent validity of a physical activity diary for measuring physical activity level and total energy expenditure in hospitalized stroke patients. Method Sixteen stroke patients kept coded activity diaries and wore SenseWear Pro2 multi-sensor activity monitors during daytime hours for one day. A researcher observed the patients and completed a diary. Data from the patients' diaries were compared with observed and measured data to determine total activity (METs*minutes), activity level and total energy expenditure. Results Spearman correlations between the patients' and researchers' diaries revealed a high correlation for total METs*minutes (rs = 0.75, p<0.01) for sedentary (rs = 0.74,p<0.01) and moderate activities (rs = 0.71,p<0.01) and a very high correlation (rs = 0.92, p<0.01) for the total energy expenditure. Comparisons between the patients' diaries and activity monitor data revealed a low correlation (rs 0.29) for total METs*minutes and energy expenditure. Conclusion Coded self-monitoring activity diaries appear feasible as a low-tech alternative to labor-intensive observational diaries for determining sedentary, moderate, and total physical activity and for quantifying energy expenditure in hospitalized stroke patients. Given the poor correlation with objective measurements of physical activity, however, further research is needed to validate its use against a gold-standard measure of physical activity intensity and energy expenditure. PMID:24905345

  8. Deciphering the mechanism behind the varied binding activities of COXIBs through Molecular Dynamic Simulations, MM-PBSA binding energy calculations and per-residue energy decomposition studies.

    PubMed

    Chaudhary, Neha; Aparoy, Polamarasetty

    2017-03-01

    COX-2 is a well-known drug target in inflammatory disorders. COX-1/COX-2 selectivity of NSAIDs is crucial in assessing the gastrointestinal side effects associated with COX-1 inhibition. Celecoxib, rofecoxib, and valdecoxib are well-known specific COX-2 inhibiting drugs. Recently, polmacoxib, a COX-2/CA-II dual inhibitor has been approved by the Korean FDA. These COXIBs have similar structure with diverse activity range. Present study focuses on unraveling the mechanism behind the 10-fold difference in the activities of these sulfonamide-containing COXIBs. In order to obtain insights into their binding with COX-2 at molecular level, molecular dynamics simulations studies, and MM-PBSA approaches were employed. Further, per-residue decomposition of these energies led to the identification of crucial amino acids and interactions contributing to the differential binding of COXIBs. The results clearly indicated that Leu338, Ser339, Arg499, Ile503, Phe504, Val509, and Ser516 (Leu352, Ser353, Arg513, Ile517, Phe518, Val523, and Ser530 in PGHS-1 numbering) were imperative in determining the activity of these COXIBs. The binding energies and energy contribution of various residues were similar in all the three simulations. The results suggest that hydrogen bond interaction between the hydroxyl group of Ser516 and five-membered ring of diarylheterocycles augments the affinity in COXIBs. The SAR of the inhibitors studied and the per-residue energy decomposition values suggested the importance of Ser516. Additionally, the positive binding energy obtained with Arg106 explains the binding of COXIBs in hydrophobic channel deep in the COX-2 active site. The findings of the present work would aid in the development of potent COX-2 inhibitors.

  9. Activities of the U. S. Department of Energy in education. Annual status report, FY 1979

    SciTech Connect

    Not Available

    1980-04-01

    The energy-related education activities administered in FY 1979 by DOE are described: projections for FY 1980 are also given. This document provides assistance for DOE program managers who wish to use the educational process in their operations, and it provides guidance and information to educators and the general public about DOE energy-related education activities. The education activities are classified as energy information (curriculum packages, studies, workshops and forums conferences, other materials), energy skills development, institutional resource enhancement, and other activities. A chart gives the category of activity, type of audience, and type of services provided. (RWR)

  10. Energy dependence on the electric activities of a neuron

    NASA Astrophysics Data System (ADS)

    Song, Xin-Lin; Jin, Wu-Yin; Ma, Jun

    2015-12-01

    A nonlinear circuit can be designed by using inductor, resistor, capacitor and other electric devices, and the electromagnetic field energy can be released from the circuit in the oscillating state. The generation of spikes or bursting states in neurons could be energetically a costly process. Based on the Helmholtz’s theorem, a Hamilton energy function is defined to detect the energy shift induced by transition of electric modes in a Hindmarsh-Rose neuron. It is found that the energy storage is dependent on the external forcing, and energy release is associated with the electric mode. As a result, the bursting state and chaotic state could be helpful to release the energy in the neuron quickly. Project supported by the National Natural Science Foundation of China (Grant Nos. 11372122 and 11365014).

  11. Solar energy in Argentina: a profile of renewable energy activity in its national context

    SciTech Connect

    Hawkins, D.

    1981-01-01

    The following subjects are included: the country overview; the energy summary; the geopolitical, economic, and cultural aspects of the Republic of Argentina; the energy profile; and international contacts, manufacturers, and projects. (MHR)

  12. [Energy index of heart rate spectral analysis for the assessment of autonomic nerve activities].

    PubMed

    Naito, T

    1991-02-01

    Heart rate spectral analysis was performed in 17 male healthy volunteers by changing their positions (supine or standing) and respiratory rates (8, 10, 12, 15 and 20 bpm). Furthermore, analysis was made by a multiple regression method on parameters such as R-R interval, tidal volume, respiratory time and positions of the subjects which may contribute to the peak power values of high frequency components (HFC, synchronous with respiratory patterns and of low frequency components (LFC, about 0.1Hz). HFC power was found to be significantly dependent on R-R interval and respiratory time, but not on tidal volume or position. Following equation was obtained. HFCP = 11.3 X RTX (RR-0.246) HFCP: HFC power value (msec) RT: respiratory time (sec) RR: R-R interval (sec) Therefore, HFCP or area under the curve (AUC) of HFC is not appropriate for the assessment of autonomic nerve activities, especially when respiratory rate or heart rate is changing. The intensity of physical wave is in proportion to (amplitude X frequency). Consequently, in a case where frequency is changeable, (amplitude X frequency) is a good index of the oscillatory energy. Therefore, sigma (power X frequency) is proposed as a suitable index for a certain component of power-spectrum. Parasympathetic activity should be assessed by the following index induced from the previously mentioned equation. RR adjusted HFEI (high frequency energy index) = sigma (power X frequency)/(RR-0.246) (0.15Hz less than frequency less than 0.4Hz). Similarly, low frequency components which reflect the sympathetic activity should be assessed by the following equation. LFEI (low frequency energy index) = sigma (power X frequency) (0.05Hz less than frequency less than 0.15Hz). The assessment of autonomic nerve activities becomes more appropriate by using these indices especially when heart rate and respiratory rate are changing.

  13. Angiotensin I-converting enzyme (ACE) inhibitory activity and ACE inhibitory peptides of salmon (Salmo salar) protein hydrolysates obtained by human and porcine gastrointestinal enzymes.

    PubMed

    Darewicz, Małgorzata; Borawska, Justyna; Vegarud, Gerd E; Minkiewicz, Piotr; Iwaniak, Anna

    2014-08-13

    The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE) inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes) and ex vivo digestion (with human gastrointestinal enzymes). Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50%) of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes.

  14. Design and Development of an Affective Interface for Supporting Energy-saving Activities and its Evaluation

    NASA Astrophysics Data System (ADS)

    Ito, Kyoko; Tomita, Daisuke; Imaki, Tomotaka; Hongo, Taishiro; Yoshikawa, Hidekazu

    Toward a sustainable society, energy and environmental issues are very important and controversial problems, and it is expected to support various human activities for the measures by using Information Technology. The purpose of this study is to develop an affective interface for supporting people's energy-saving activities. First, a model for supporting people's energy-saving activities involving affective elements has been constructed for supporting people's energy-saving activities, based on social psychological approaches. Based on the proposed model, the requirements on an affective interface for people's energy-saving activities have been considered. In this study, the affective interface presents suitable energy-saving activities and current electric energy consumption by a character agent with a graphical shape and synthesized voice. The character agent recommends people's energy-saving activities, tells the method of energy-saving activities and the effectiveness, and so on. The affective interface for supporting energy-saving activities has been designed in detail and developed. Then, the evaluation experiment of the developed interface has been conducted, and the results of the experiments were analyzed.

  15. Industrial Technology. Iowa Developed Energy Activity Sampler, 6-12. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines. Div. of Instructional Services.

    The revised Iowa Developed Energy Activity Sampler (IDEAS) was compiled using the original IDEAS program and the Energy Conservation Activity Packets (ECAPS). This document is one of a series of revised IDEAS booklets, and provides learning activities for teachers to use with students in industrial arts/technology education. Each of the 17…

  16. High Energy Physics Division semiannual report of research activities, July 1, 1996 - December 31, 1996

    SciTech Connect

    Norem, J.; Rezmer, R.; Wagner, R.

    1997-12-01

    This report is divided into the following areas: (1) experimental research program; (2) theoretical research program; (3) accelerator research and development; (4) divisional computing activities; (5) publications; (6) colloquia and conference talks; (7) high energy physics community activities; and (7) High Energy Physics Division research personnel. Summaries are given for individual research programs for activities (1), (2) and (3).

  17. Anti-inflammatory and antioxidant activities, functional properties and mutagenicity studies of protein and protein hydrolysate obtained from Prosopis alba seed flour.

    PubMed

    Cattaneo, Florencia; Sayago, Jorge Esteban; Alberto, María Rosa; Zampini, Iris Catiana; Ordoñez, Roxana Mabel; Chamorro, Verónica; Pazos, Adriana; Isla, María Inés

    2014-10-15

    Prosopis species are considered multipurpose trees and shrubs by FAO and their fruit constitute a food source for humans and animals. According to the "Código Alimentario Argentino", "algarrobo flour" is produced by grinding the whole mature pod, but in the traditional process most of the seeds are discarded. In this paper, the flour from seed was obtained. Then, the proteins were extracted and enzymatic hydrolysis was carried out. According to their amino acid profile and chemical score (>100%), the Prosopis alba proteins, are not deficient in essential amino acids considering the amount of amino acid necessary by adults. The protein isolate showed a good solubility (pH 7.4-9), emulsificant capacity, oil binding capacity and water adsorption capacity. The antioxidant ability of proteins was significantly increased with hydrolysis (SC50 values: 50-5μg/mL, respectively). Inhibitory activity of pro-inflammatory enzymes (lipoxygenase and phospholipase) was described. The mutagenicity/antimutagenicity of proteins and protein hydrolysates from seed flour were also analysed. The results suggest that P. alba cotyledon flour could be a new alternative in the formulation of functional foods not only for its high protein content but also by the biological and functional properties of its proteins and protein hydrolysates.

  18. Oxidative degradation of trichloroethylene adsorbed on active carbons: Use of microwave energy

    SciTech Connect

    Varma, R.; Nandi, S.P.

    1991-01-01

    Chlorinated hydrocarbon compounds (CHCl), such as chlorinated alkanes/alkenes, benzene and biphenyl etc, represent an important fraction of the industrial hazardous wastes produced. Trichloroethylene (TCE) can be removed from waste streams by adsorption on active carbons. The primary objective of the present work was to study the detoxification in air-stream of TCE adsorbed on different types of active carbons using in situ microwave heating. A secondary objective was to examine the regeneration of used carbons from the effects of repeated cyclic operations (adsorption- detoxification). The experimental study has shown that trichloroethylene adsorbed on active carbon can be oxidatively degradated in presence of microwave radiation. Energy can be transferred efficiently to the reaction sites without losing heat to the surrounding vessel. One of the decomposition product of trichloroethylene is free chlorine which is held very strongly on active carbon. Hydrochloric acid on the other hand seems to be less strongly held and appears in large concentration in the exit gas. Production of free chlorine can be avoided by using chlorohydrocarbon mixed with sufficient internal hydrogen. This is also expected to minimize the problem of carbon regeneration encountered in this study. The results obtained from studies on the oxidative degradation of TCE under microwave radiation are promising in a number of respects: (1) the detoxification of TCE adsorbed on active carbon can be conducted at moderate (<400{degree}C) temperatures, and (2) the used carbon bed can be regenerated. A patent on the process has been issued. 9 refs., 2 figs., 2 tabs.

  19. Physical activity, sedentary behaviour and energy balance in the preschool child: opportunities for early obesity prevention.

    PubMed

    Reilly, John J

    2008-08-01

    Prevalence of obesity in preschool children has increased dramatically in recent years. The preschool years (age 3-6 years) have been regarded as critical for the programming of energy balance, via the concept of early 'adiposity rebound'. Children who undergo early adiposity rebound are at increased risk of later obesity. Recent evidence suggests that associations between timing of adiposity rebound and later obesity may not reflect programming, but might denote that 'obesogenic' growth trajectories are often established by the preschool period. Studies of objectively-measured physical activity and sedentary behaviour in preschool children show that levels of physical activity are typically low and sedentary behaviour high. The review of evidence presented here is supportive of the hypothesis that physical activity is protective against obesity in the preschool period, and that sedentary behaviour, particularly television viewing, is obesogenic. Definitive evidence on dose-response relationships between physical activity, sedentary behaviour and obesity remain unclear. Dose-response evidence could be obtained fairly readily by intervention and longitudinal observational studies that use accelerometry in preschool children. The generalisability of much of the evidence base is limited and there is a need for research on the influence of physical activity and sedentary behaviour in the preschool years in the aetiology of obesity in the developing world.

  20. Communicating Wave Energy: An Active Learning Experience for Students

    ERIC Educational Resources Information Center

    Huynh, Trongnghia; Hou, Gene; Wang, Jin

    2016-01-01

    We have conducted an education project to communicate the wave energy concept to high school students. A virtual reality system that combines both hardware and software is developed in this project to simulate the buoy-wave interaction. This first-of-its-kind wave energy unit is portable and physics-based, allowing students to conduct a number of…

  1. 76 FR 65634 - Assistance to Foreign Atomic Energy Activities

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-24

    ... Security Administration, U.S. Department of Energy, Office of Defense Nuclear Nonproliferation (NA-20... Washington, DC on October 18, 2011. Anne Harrington, Deputy Administrator for Defense Nuclear Nonproliferation, National Nuclear Security Administration, U.S. Department of Energy. BILLING CODE 6450-01-P...

  2. Final Report 02-ERD-056 Active Load Control& Mitigation Using Microtabs: A Wind Energy Application

    SciTech Connect

    Nakafuji, D Y

    2003-02-24

    energy market penetration and improving the reliability of the nation's renewable electrical generation infrastructure. This project also provides enabling technologies for improving turbine efficiency and durability to support the DOE and NNSA missions of providing energy security and reliability without contributing to greenhouse gas emissions and for decreasing dependence on foreign fuel sources. In addition to wind generator applications, the realization of a ''smart'' controllable structure for load control using the microtab approach has the potential to revolutionize design of other complex systems. Driven by cost and safety, both passive and active flow control for steady and unsteady conditions have been actively investigated by NASA, DARPA, DOE and other research institutions for application on rotorcraft, UAVs, marine vessels and wind turbine applications. The potential to obtain revolutionary advances in aerodynamic hydrodynamic performance, safety, maneuverability and service life by decreasing loads is an attractive prospect across many industries.

  3. Mississippi Renewable Energy and Energy Efficiency Report. A snap shot of related activities in the state of Mississippi

    SciTech Connect

    Arora, Sumesh M.; Linton, Joseph A.

    2011-05-11

    In recent years, due to concerns over national security from both economic and military standpoints, increased attention has been given to the production of renewable energy in order to reduce American dependence on foreign supplies of energy. These concerns, along with those related to the effect of fossil fuels on the environment, have served to heighten the enthusiasm for finding replacements for traditional energy sources, along with helping to highlight the need for energy efficiency in American homes and businesses. Throughout the nation, this has been exemplified in an increased entrepreneurial activity to produce liquid fuels, thermal energy and electricity from a vast range of sources such as plants, trees, bacteria, the sun, wind, waves and the Earth itself. Coupled with tax subsidies, loan guarantees, renewable fuel standards, and various other government incentives and legislative encouragements we have seen a big jump in the production of renewable energy in the United States in the last ten years. But we are just getting started!

  4. U.S. Department of Energy thermal energy storage research activities review: 1989 Proceedings

    SciTech Connect

    Hoffman, H.W.; Tomlinson, J.J.

    1989-03-01

    Thermal Energy Storage (TES) offers the opportunity for the recovery and re-use of heat currently rejected to the ambient environment. Further, through the ability of TES to match an energy supply with a thermal energy demand, TES increases efficiencies of energy systems and improves capacity factors of power plants. The US Department of Energy has been the leader in TES research, development, and demonstration since recognition in 1976 of the need for fostering energy conservation as a component of the national energy budget. The federal program on TES R and D is the responsibility of the Office of Energy Storage and Distribution within the US Department of Energy (DOE). The overall program is organized into three program areas: diurnal--relating primarily to lower temperature heat for use in residential and commercial buildings on a daily cycle; industrial--relating primarily to higher temperature heat for use in industrial and utility processes on an hourly to daily cycle; seasonal--relating primarily to lower temperature heat or chill for use in residential complexes (central supply as for apartments or housing developments), commercial (light manufacturing, processing, or retail), and industrial (space conditioning) on a seasonal to annual cycle. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  5. Superior photoluminescence and photocatalytic activity of CdS (core)-SiO2 (shell) nanostructures obtained by CdS photoetching and Au deposition.

    PubMed

    Gupta, Nidhi; Pal, Bonamali

    2013-07-01

    Core-shell morphology of silica (SiO2) coated CdS nanocomposites (SiO2@CdS) of different shapes have been made for better stability, luminescence and photochemical activity of CdS nanoparticles. A thin layer (thickness 1-1.4 nm) of SiO2 shell is deposited over CdS nanorods (CdS-NR) of aspect ratio = 21 and CdS nanospheres (CdS-NS) of size 6-8 nm by alkyl silane agents. Synthesized nanostructures were characterized by diffuse reflectance spectra, HR-TEM, BET surface measurement, LB surface film, and absorption and photoluminescence analysis. Photoetching (PE) of CdS core led to blue shift of the absorbance onset of SiO2@CdS-NR along with the appearance of an exciton band at 485 nm due to the quantum confinement effect. Photodissolution of CdS core shifts the band gap energy from initial 2.4 to 2.6 eV for CdS-NR and 2.5 to 2.67 eV for CdS-NS. TEM images reveal the increase in aspect ratio of NR from 21 to 31 and decrease in the spherical core to 2.5 nm from 6-8 nm after PE. Photoetched SiO2@CdS-NC displayed highly intense fluorescence emission (SiO2@CdS-NS > SiO2@CdS-NR) than unetched SiO2@CdS-NC at 488 nm corresponding to band edge position. The Au (0.5 wt.%) deposition onto photoetched SiO2@CdS-NR(PE) composites highly enhanced the fluorescence intensity in comparison to 1 wt.% of Au and Ag loading. SiO2@CdS-NC(PE) displayed improved photocatalytic activity during benzaldehyde photooxidation under UV (125 W, Hg-arc, 10.4 mW/cm2) irradiation. Silica coating onto CdS particles improves the photostability and photoactivity of CdS upon long UV irradiation.

  6. The Limit of Magnetic-Shear Energy in Solar Active Regions

    NASA Technical Reports Server (NTRS)

    Moore, Ronald L.; Falconer, David A.; Sterling, Alphonse C.

    2013-01-01

    It has been found previously, by measuring from active ]region magnetograms a proxy of the free energy in the active region fs magnetic field, (1) that there is a sharp upper limit to the free energy the field can hold that increases with the amount of magnetic field in the active region, the active region fs magnetic flux content, and (2) that most active regions are near this limit when their field explodes in a CME/flare eruption. That is, explosive active regions are concentrated in a main ]sequence path bordering the free ]energy ]limit line in (flux content, free ]energy proxy) phase space. Here we present evidence that specifies the underlying magnetic condition that gives rise to the free ]energy limit and the accompanying main sequence of explosive active regions. Using a suitable free energy proxy measured from vector magnetograms of 44 active regions, we find evidence that (1) in active regions at and near their free ]energy limit, the ratio of magnetic ]shear free energy to the non ]free magnetic energy the potential field would have is of order 1 in the core field, the field rooted along the neutral line, and (2) this ratio is progressively less in active regions progressively farther below their free ]energy limit. Evidently, most active regions in which this core ]field energy ratio is much less than 1 cannot be triggered to explode; as this ratio approaches 1, most active regions become capable of exploding; and when this ratio is 1, most active regions are compelled to explode.

  7. The Limit of Magnetic-Shear Energy in Solar Active Regions

    NASA Technical Reports Server (NTRS)

    Moore, Ronald; Falconer, David; Sterling, Alphonse

    2012-01-01

    It has been found previously, by measuring from active-region magnetograms a proxy of the free energy in the active region's magnetic field, (1) that there is a sharp upper limit to the free energy the field can hold that increases with the amount of magnetic field in the active region, the active region's magnetic flux content, and (2) that most active regions are near this limit when their field explodes in a coronal mass ejection/flare eruption. That is, explosive active regions are concentrated in a main-sequence path bordering the free-energy-limit line in (flux content, free-energy proxy) phase space. Here, we present evidence that specifies the underlying magnetic condition that gives rise to the free-energy limit and the accompanying main sequence of explosive active regions. Using a suitable free-energy proxy measured from vector magnetograms of 44 active regions, we find evidence that (1) in active regions at and near their free-energy limit, the ratio of magnetic-shear free energy to the non-free magnetic energy the potential field would have is of the order of one in the core field, the field rooted along the neutral line, and (2) this ratio is progressively less in active regions progressively farther below their free-energy limit. Evidently, most active regions in which this core-field energy ratio is much less than one cannot be triggered to explode; as this ratio approaches one, most active regions become capable of exploding; and when this ratio is one, most active regions are compelled to explode.

  8. Identification of general linear relationships between activation energies and enthalpy changes for dissociation reactions at surfaces.

    PubMed

    Michaelides, Angelos; Liu, Z-P; Zhang, C J; Alavi, Ali; King, David A; Hu, P

    2003-04-02

    The activation energy to reaction is a key quantity that controls catalytic activity. Having used ab inito calculations to determine an extensive and broad ranging set of activation energies and enthalpy changes for surface-catalyzed reactions, we show that linear relationships exist between dissociation activation energies and enthalpy changes. Known in the literature as empirical Brønsted-Evans-Polanyi (BEP) relationships, we identify and discuss the physical origin of their presence in heterogeneous catalysis. The key implication is that merely from knowledge of adsorption energies the barriers to catalytic elementary reaction steps can be estimated.

  9. Obtain Resources for Climate & Energy Programs

    EPA Pesticide Factsheets

    This phase of the Local Climate Action Framework will help users identify and pursue the resources needed for program/project implementation, including internal or external funding, existing or new staff time, technical expertise, or stakeholder buy-in.

  10. SU-E-T-212: Comparison of TG-43 Dosimetric Parameters of Low and High Energy Brachytherapy Sources Obtained by MCNP Code Versions of 4C, X and 5

    SciTech Connect

    Zehtabian, M; Zaker, N; Sina, S; Meigooni, A Soleimani

    2015-06-15

    Purpose: Different versions of MCNP code are widely used for dosimetry purposes. The purpose of this study is to compare different versions of the MCNP codes in dosimetric evaluation of different brachytherapy sources. Methods: The TG-43 parameters such as dose rate constant, radial dose function, and anisotropy function of different brachytherapy sources, i.e. Pd-103, I-125, Ir-192, and Cs-137 were calculated in water phantom. The results obtained by three versions of Monte Carlo codes (MCNP4C, MCNPX, MCNP5) were compared for low and high energy brachytherapy sources. Then the cross section library of MCNP4C code was changed to ENDF/B-VI release 8 which is used in MCNP5 and MCNPX codes. Finally, the TG-43 parameters obtained using the MCNP4C-revised code, were compared with other codes. Results: The results of these investigations indicate that for high energy sources, the differences in TG-43 parameters between the codes are less than 1% for Ir-192 and less than 0.5% for Cs-137. However for low energy sources like I-125 and Pd-103, large discrepancies are observed in the g(r) values obtained by MCNP4C and the two other codes. The differences between g(r) values calculated using MCNP4C and MCNP5 at the distance of 6cm were found to be about 17% and 28% for I-125 and Pd-103 respectively. The results obtained with MCNP4C-revised and MCNPX were similar. However, the maximum difference between the results obtained with the MCNP5 and MCNP4C-revised codes was 2% at 6cm. Conclusion: The results indicate that using MCNP4C code for dosimetry of low energy brachytherapy sources can cause large errors in the results. Therefore it is recommended not to use this code for low energy sources, unless its cross section library is changed. Since the results obtained with MCNP4C-revised and MCNPX were similar, it is concluded that the difference between MCNP4C and MCNPX is their cross section libraries.

  11. 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.

  12. 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

  13. Observing Quantum Monodromy: AN Energy-Momentum Map Built from Experimentally-Determined Level Energies Obtained from the νb{7} Far-Infrared Band System of Ncncs

    NASA Astrophysics Data System (ADS)

    Tokaryk, Dennis W.; Ross, Stephen Cary; Winnewisser, Brenda P.; Winnewisser, Manfred; De Lucia, Frank C.; Billinghurst, Brant E.

    2016-06-01

    The concept of Quantum Monodromy (QM) provides a fresh insight into the structure of rovibrational levels in those flexible molecules for which a bending mode can carry the molecule through the linear configuration. To confirm the existence of QM in a molecule required the fruits of several strands of development: the formulation of the abstract mathematical concept of monodromy, including the exploration of its relevance to systems described by classical mechanics and its manifestation in quantum molecular applications; the development of the required spectroscopic technology and computer-aided assignment; and the development of a theoretical model to apply in fitting to the observed data. We present a timeline for each of these strands, converging in our initial confirmation of QM in NCNCS from pure rotational data alone. In that work a Generalised SemiRigid Bender (GSRB) Hamiltonian was fitted to the experimental rotational structure. Rovibrational energies calculated from the fitted GSRB parameters allowed us to construct an ``Energy-Momentum" map and confirm the presence of QM in NCNCS. In further experimental work at the Canadian Light Source Synchrotron we have identified a network of transitions directly connecting the relevant energy levels and thereby have produced a refined Energy Momentum map for NCNCS from experimental measurements alone. This map extends from the ground vibrational level to well above the potential energy barrier, beautifully illustrating the characteristic signature of QM in a system uncomplicated by interaction with other vibrational modes. B. P. Winnewisser et al., Phys. Rev. Lett. 95, 243002 (2005)

  14. A summary of USSR thermionic energy conversion activity

    NASA Technical Reports Server (NTRS)

    Rasor, N. S.

    1978-01-01

    The paper surveys the research and development associated with thermionic energy conversion in the USSR. Consideration is given to the basic physics of the thermionic converter, the development of thermionic nuclear reactors including the three TOPAZ models, radioisotope-heated generators, and the thermionic topping of fossil-fueled electric-power plants. Comparisons are made between U.S. and USSR capabilities in thermionic energy conversion and potential cooperative programs are noted.

  15. Minimum Energy Requirements for Sustained Microbial Activity in Anoxic Sediments

    NASA Technical Reports Server (NTRS)

    Hoehler, Tori M.; Alperin, Marc J.; Albert, Daniel B.; Martens, Christoper S.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    Currently understood mechanisms of biochemical energy conservation dictate that, in order to be biologically useful, energy must be available to organisms in "quanta" equal to, at minimum one-third to one-fifth of the energy required to synthesize ATP in vivo. The existence of this biological energy quantum means that a significant fraction of the chemical amp on Earth cannot be used to drive biological productivity, and places a fundamental thermodynamic constraint on the origins, evolution, and distribution of life. We examined the energy requirements of intact microbial assemblages in anoxic sediments from Cape Lookout Bight, NC, USA, using dissolved hydrogen concentrations as a non-invasive probe. In this system, the thermodynamics of metabolic processes occurring inside microbial cells is reflected quantitatively by H2 concentrations measured outside those cells. We find that methanogenic archaea are supported by energy yields as small as 10 kJ per mol, about half the quantity calculated from studies of microorganisms in culture. This finding implies that a significantly broader range of geologic and chemical niches might be exploited by microorganisms than would otherwise be expected.

  16. Energy Expenditure of Selected Household Activities during Pregnancy

    ERIC Educational Resources Information Center

    Chasan-Taber, Lisa; Freedson, Patty S.; Roberts, Dawn E.; Schmidt, Michael D.; Fragala, Maren S.

    2007-01-01

    Accurately measuring pregnancy physical activity is critical to assess the percentage of pregnant women meeting the American College of Obstetricians and Gynecologists (ACOG) guidelines. In addition, valid assessment of pregnancy physical activity is important for epidemiologic studies assessing the relationship between physical activity and…

  17. Energy and Change. Elementary Science Activity Series, Volume 3.

    ERIC Educational Resources Information Center

    Blackwell, Frank F.

    This book is number 3 of a series of elementary science books that presents a wealth of ideas for science activities for the elementary school teacher. Each activity includes a standard set of information designed to help teachers determine the activity's appropriateness for their students, plan its implementation, and help children focus on a…

  18. Method for Determining the Activation Energy Distribution Function of Complex Reactions by Sieving and Thermogravimetric Measurements.

    PubMed

    Bufalo, Gennaro; Ambrosone, Luigi

    2016-01-14

    A method for studying the kinetics of thermal degradation of complex compounds is suggested. Although the method is applicable to any matrix whose grain size can be measured, herein we focus our investigation on thermogravimetric analysis, under a nitrogen atmosphere, of ground soft wheat and ground maize. The thermogravimetric curves reveal that there are two well-distinct jumps of mass loss. They correspond to volatilization, which is in the temperature range 298-433 K, and decomposition regions go from 450 to 1073 K. Thermal degradation is schematized as a reaction in the solid state whose kinetics is analyzed separately in each of the two regions. By means of a sieving analysis different size fractions of the material are separated and studied. A quasi-Newton fitting algorithm is used to obtain the grain size distribution as best fit to experimental data. The individual fractions are thermogravimetrically analyzed for deriving the functional relationship between activation energy of the degradation reactions and the particle size. Such functional relationship turns out to be crucial to evaluate the moments of the activation energy distribution, which is unknown in terms of the distribution calculated by sieve analysis. From the knowledge of moments one can reconstruct the reaction conversion. The method is applied first to the volatilization region, then to the decomposition region. The comparison with the experimental data reveals that the method reproduces the experimental conversion with an accuracy of 5-10% in the volatilization region and of 3-5% in the decomposition region.

  19. Solar Energy Education. Renewable energy activities for junior high/middle school science

    SciTech Connect

    Not Available

    1985-01-01

    Some basic topics on the subject of solar energy are outlined in the form of a teaching manual. The manual is geared toward junior high or middle school science students. Topics include solar collectors, solar water heating, solar radiation, insulation, heat storage, and desalination. Instructions for the construction of apparatus to demonstrate the solar energy topics are provided. (BCS)

  20. DOE/NREL supported wind energy activities in Alaska

    SciTech Connect

    Drouilhet, S.

    1997-12-01

    This paper describes three wind energy projects implemented in Alaska. The first, a sustainable technology energy partnerships (STEP) wind energy deployment project in Kotzebue will install 6 AOC 15/50 wind turbines and connect to the existing village diesel grid, consisting of approximately 1 MW average load. It seeks to develop solutions to the problems of arctic wind energy installations (transport, foundations, erection, operation, and maintenance), to establish a wind turbine test site, and to establish the Kotzebue Electric Association as a training and deployment center for wind/diesel technology in rural Alaska. The second project, a large village medium-penetration wind/diesel system, also in Kotzebue, will install a 1-2 MW windfarm, which will supplement the AOC turbines of the STEP project. The program will investigate the impact of medium penetration wind energy on power quality and system stability. The third project, the Alaska high-penetration wind/diesel village power pilot project in Wales will install a high penetration (80-100%) wind/diesel system in a remote Alaskan village. The system will include about 180 kW installed wind capacity, meeting an average village load of about 60 kW. This program will provide a model for high penetration wind retrofits to village diesel power systems and build the capability in Alaska to operate, maintain, and replicate wind/diesel technology. The program will also address problems of: effective use of excess wind energy; reliable diesel-off operation; and the role of energy storage.

  1. Disturbance of wildlife by outdoor winter recreation: allostatic stress response and altered activity-energy budgets.

    PubMed

    Arlettaz, Raphaël; Nusslé, Sébastien; Baltic, Marjana; Vogel, Peter; Palme, Rupert; Jenni-Eiermann, Susanne; Patthey, Patrick; Genoud, Michel

    2015-07-01

    Anthropogenic disturbance of wildlife is of growing conservation concern, but we lack comprehensive approaches of its multiple negative effects. We investigated several effects of disturbance by winter outdoor sports on free-ranging alpine Black Grouse by simultaneously measuring their physiological and behavioral responses. We experimentally flushed radio-tagged Black Grouse from their snow burrows, once a day, during several successive days, and quantified their stress hormone levels (corticosterone metabolites in feces [FCM] collected. from individual snow burrows). We also measured feeding time allocation (activity budgets reconstructed from radio-emitted signals) in response to anthropogenic disturbance. Finally, we estimated the related extra energy expenditure that may be incurred: based on activity budgets, energy expenditure was modeled from measures of metabolism obtained from captive birds subjected to different ambient temperatures. The pattern of FCM excretion indicated the existence of a funneling effect as predicted by the allostatic theory of stress: initial stress hormone concentrations showed a wide inter-individual variation, which decreased during experimental flushing. Individuals with low initial pre-flushing FCM values augmented their concentration, while individuals with high initial FCM values lowered it. Experimental disturbance resulted in an extension of feeding duration during the following evening foraging bout, confirming the prediction that Black Grouse must compensate for the extra energy expenditure elicited by human disturbance. Birds with low initial baseline FCM concentrations were those that spent more time foraging. These FCM excretion and foraging patterns suggest that birds with high initial FCM concentrations might have been experiencing a situation of allostatic overload. The energetic model provides quantitative estimates of extra energy expenditure. A longer exposure to ambient temperatures outside the shelter of snow

  2. Unfolding neutron energy spectra from foil activation detector measurements with the Gold algorithm

    NASA Astrophysics Data System (ADS)

    Seghour, A.; Seghour, F. Z.

    2001-01-01

    In this work, the Gold algorithm is applied to the unfolding of neutron reactor energy spectra from reaction rates data of multiple foil activation detectors. Such a method, which forms the basis of a developed unfolding computer program called SAYD, has the advantage of not requiring a priori knowledge on the spectrum in the unfolding process. The program SAYD is first illustrated by synthesized reaction rates data calculated using a semi-empirical formulation of a typical intermediate and fast neutron reactor spectrum. The demonstration of the unfolding program SAYD is next achieved using measured reaction rates of the Arkansas Nuclear One power plant (ANO) benchmark spectrum by comparing results of SAYD program with those obtained by STAYNL and MSANDB unfolding codes.

  3. Young Scientists Explore an Encyclopedia of Energy Activities. Book 8--Intermediate Level. A Good Apple Activity Book.

    ERIC Educational Resources Information Center

    DeBruin, Jerry

    Designed to develop creativity in young learners, this book contains interdisciplinary activities which focus on the theme of energy. Activity pages are provided that can serve as front and back covers of a student booklet and the suggested activities can be duplicated for insertion between the covers resulting in a booklet for each student. A…

  4. Office of Inspector General audit report on the U.S. Department of Energy`s aircraft activities

    SciTech Connect

    1999-01-01

    On October 19, 1998, the Office of Inspector General (OIG) was asked to undertake a review of the Department of Energy`s aircraft activities. It was also requested that they report back within 90 days. The OIG has gathered information concerning the number of aircraft, the level of utilization, and the cost of the Department`s aircraft operations. They have also briefly summarized four issues that, in their judgment, may require management attention.

  5. THE INTEGRAL HIGH-ENERGY CUT-OFF DISTRIBUTION OF TYPE 1 ACTIVE GALACTIC NUCLEI

    SciTech Connect

    Malizia, A.; Molina, M.; Bassani, L.; Stephen, J. B.; Bazzano, A.; Ubertini, P.; Bird, A. J.

    2014-02-20

    In this Letter we present the primary continuum parameters, the photon index Γ, and the high-energy cut-off E {sub c} of 41 type-1 Seyfert galaxies extracted from the International Gamma-Ray Astrophysics Laboratory (INTEGRAL) complete sample of active galactic nuclei (AGNs). We performed broadband (0.3-100 keV) spectral analysis by simultaneously fitting the soft and hard X-ray spectra obtained by XMM and INTEGRAL/IBIS-Swift/BAT, respectively, in order to investigate the general properties of these parameters, in particular their distribution and mean values. We find a mean photon index of 1.73 with a standard deviation of 0.17 and a mean high-energy cut-off of 128 keV with a standard deviation of 46 keV for the whole sample. This is the first time that the cut-off energy is constrained in such a large number of AGNs. We have 26 measurements of the cut-off, which corresponds to 63% of the entire sample, distributed between 50 and 200 keV. There are a further 11 lower limits mostly below 300 keV. Using the main parameters of the primary continuum, we have been able to obtain the actual physical parameters of the Comptonizing region, i.e., the plasma temperature kT {sub e} from 20 to 100 keV and the optical depth τ < 4. Finally, with the high signal-to-noise ratio spectra starting to come from NuSTAR it will soon be possible to better constrain the cut-off values in many AGNs, allowing the determination of more physical models and thus better understand the continuum emission and geometry of the region surrounding black holes.

  6. The INTEGRAL High-energy Cut-off Distribution of Type 1 Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Malizia, A.; Molina, M.; Bassani, L.; Stephen, J. B.; Bazzano, A.; Ubertini, P.; Bird, A. J.

    2014-02-01

    In this Letter we present the primary continuum parameters, the photon index Γ, and the high-energy cut-off E c of 41 type-1 Seyfert galaxies extracted from the International Gamma-Ray Astrophysics Laboratory (INTEGRAL) complete sample of active galactic nuclei (AGNs). We performed broadband (0.3-100 keV) spectral analysis by simultaneously fitting the soft and hard X-ray spectra obtained by XMM and INTEGRAL/IBIS-Swift/BAT, respectively, in order to investigate the general properties of these parameters, in particular their distribution and mean values. We find a mean photon index of 1.73 with a standard deviation of 0.17 and a mean high-energy cut-off of 128 keV with a standard deviation of 46 keV for the whole sample. This is the first time that the cut-off energy is constrained in such a large number of AGNs. We have 26 measurements of the cut-off, which corresponds to 63% of the entire sample, distributed between 50 and 200 keV. There are a further 11 lower limits mostly below 300 keV. Using the main parameters of the primary continuum, we have been able to obtain the actual physical parameters of the Comptonizing region, i.e., the plasma temperature kT e from 20 to 100 keV and the optical depth τ < 4. Finally, with the high signal-to-noise ratio spectra starting to come from NuSTAR it will soon be possible to better constrain the cut-off values in many AGNs, allowing the determination of more physical models and thus better understand the continuum emission and geometry of the region surrounding black holes.

  7. Technology Learning Activities. Design Brief--Measuring Inaccessible Distances. Alternative Energy Sources: Designing a Wind Powered Generator. Alternative Energy Sources: Designing a Hot Dog Heater Using Solar Energy.

    ERIC Educational Resources Information Center

    Technology Teacher, 1991

    1991-01-01

    These three learning activities are on measuring accessible distances, designing a wind powered generator, and designing a hot dog heater using solar energy. Each activity includes description of context, objectives, list of materials and equipment, challenge to students, and evaluation questions. (SK)

  8. Designing an Energy Drink: High School Students Learn Design and Marketing Skills in This Activity

    ERIC Educational Resources Information Center

    Martin, Doug

    2008-01-01

    A decade ago, energy drinks were almost nonexistent in the United States, but in the past five years they've become wildly popular. In fact, the $3.4 billion energy-drink market is expected to double this year alone, and the younger generation is the market targeted by manufacturers. This article presents an energy-drink designing activity. This…

  9. Illustrating the Effect of pH on Enzyme Activity Using Gibbs Energy Profiles

    ERIC Educational Resources Information Center

    Bearne, Stephen L.

    2014-01-01

    Gibbs energy profiles provide students with a visual representation of the energy changes that occur during enzyme catalysis, making such profiles useful as teaching and learning tools. Traditional kinetic topics, such as the effect of pH on enzyme activity, are often not discussed in terms of Gibbs energy profiles. Herein, the symbolism of Gibbs…

  10. Renewable energy and rural development activities experience in Bangladesh

    SciTech Connect

    Barua, D.C.

    1997-12-01

    The per capita per year fuel consumption in Bangladesh is only 56 kg oil equivalent. The supply of electricity by Bangladesh power development board (BPDB) and Dhaka electricity supply authority (DESA) is mainly confined to cities and towns. Rural Electrification Board (REB) distributes electricity to the rural people through cooperatives. The rural cooperatives cover only 10% of the total population. Only about 15% of the total population is directly connected to the electricity. In order to meet the increasing energy demand for development of agriculture and industry and for the generation of better employment opportunities, it will be necessary to harness all the available alternative sources of energy immediately.

  11. Self-powered suspension criterion and energy regeneration implementation scheme of motor-driven active suspension

    NASA Astrophysics Data System (ADS)

    Yan, Shuai; Sun, Weichao

    2017-09-01

    Active suspension systems have advantages on mitigating the effects of vehicle vibration caused by road roughness, which are one of the most important component parts in influencing the performances of vehicles. However, high amount of energy consumption restricts the application of active suspension systems. From the point of energy saving, this paper presents a self-powered criterion of the active suspension system to judge whether a motor-driven suspension can be self-powered or not, and then a motor parameter condition is developed as a reference to design a self-powered suspension. An energy regeneration implementation scheme is subsequently proposed to make the active suspension which has the potential to be self-powered achieve energy-saving target in the real application. In this implementation scheme, operating electric circuits are designed based on different working status of the actuator and power source and it is realizable to accumulate energy from road vibration and supply energy to the actuator by switching corresponding electric circuits. To apply the self-powered suspension criterion and energy regeneration implementation scheme, an active suspension system is designed with a constrained H∞ controller and calculation results indicate that it has the capability to be self-powered. Simulation results show that the performances of the self-powered active suspension are nearly the same as those of the active suspension with an external energy source and can achieve energy regeneration at the same time.

  12. Serum metabolites related to cardiorespiratory fitness, physical activity energy expenditure, sedentary time and vigorous activity.

    PubMed

    Wientzek, Angelika; Floegel, Anna; Knüppel, Sven; Vigl, Matthaeus; Drogan, Dagmar; Adamski, Jerzy; Pischon, Tobias; Boeing, Heiner

    2014-04-01

    The aim of our study was to investigate the relationship between objectively measured physical activity (PA) and cardiorespiratory fitness (CRF) and serum metabolites measured by targeted metabolomics in a population- based study. A total of 100 subjects provided 2 fasting blood samples and engaged in a CRF and PA measurement at 2 visits 4 months apart. CRF was estimated from a step test, whereas physical activity energy expenditure (PAEE), time spent sedentary and time spend in vigorous activity were measured by a combined heart rate and movement sensor for a total of 8 days. Serum metabolite concentrations were determined by flow injection analysis tandem mass spectrometry (FIA-MS/MS). Linear mixed models were applied with multivariable adjustment and p-values were corrected for multiple testing. Furthermore, we explored the associations between CRF, PA and two metabolite factors that have previously been linked to risk of Type 2 diabetes. CRF was associated with two phosphatidylcholine clusters independently of all other exposures. Lysophosphatidylcholine C14:0 and methionine were significantly negatively associated with PAEE and sedentary time. CRF was positively associated with the Type 2 diabetes protective factor. Vigorous activity was positively associated with the Type 2 diabetes risk factor in the mutually adjusted model. Our results suggest that CRF and PA are associated with serum metabolites, especially CRF with phosphatidylcholines and with the Type 2 diabetes protective factor. PAEE and sedentary time were associated with methionine. The identified metabolites could be potential mediators of the protective effects of CRF and PA on chronic disease risk.

  13. Iowa Developed Energy Activity Sampler (IDEAS), Grades 7-12: Science.

    ERIC Educational Resources Information Center

    Simonis, Doris G.

    Presented is the Science component of the Iowa Developed Energy Activity Sampler (IDEAS), a multidisciplinary energy education program designed for infusion into the curriculum of grades 7-12. Also contained in the program are activity sets for Home Economics (SE 034 678), Industrial Arts (SE 034 679), Language Arts (SE 034 680), Mathematics (SE…

  14. Determination of the Arrhenius Activation Energy Using a Temperature-Programmed Flow Reactor.

    ERIC Educational Resources Information Center

    Chan, Kit-ha C.; Tse, R. S.

    1984-01-01

    Describes a novel method for the determination of the Arrhenius activation energy, without prejudging the validity of the Arrhenius equation or the concept of activation energy. The method involves use of a temperature-programed flow reactor connected to a concentration detector. (JN)

  15. Iowa Developed Energy Activity Sampler (IDEAS), Grades 7-12: Home Economics.

    ERIC Educational Resources Information Center

    Simonis, Doris G.

    Presented is the Home Economics component of the Iowa Developed Energy Activity Sampler (IDEAS), a multidisciplinary energy education program designed for infusion into the curriculum of grades 7-12. Also included in the program are activity sets for Industrial Arts (SE 034 679), Language Arts (SE 034 680), Mathematics (SE 034 681), Science (SE…

  16. Iowa Developed Energy Activity Sampler (IDEAS), Grades 7-12: Introduction.

    ERIC Educational Resources Information Center

    Simonis, Doris G.

    Presented is the Introduction for the Iowa Developed Energy Activity Sampler (IDEAS), a multidisciplinary energy education program designed for infusion into the curriculum of grades 7-12. Included in the program are activity sets for Home Economics (SE 034 678), Industrial Arts (SE 034 679), Language Arts (SE 034 680), Mathematics (SE 034 681),…

  17. Iowa Developed Energy Activity Sampler 6-12. Home Economics. Revised.

    ERIC Educational Resources Information Center

    Iowa State Dept. of Education, Des Moines. Div. of Instructional Services.

    This set of activities is intended to assist home economics teachers in incorporating basic energy education concepts into traditional home economics topics. Awareness activities that are intended to help students develop an understanding of fundamental energy conservation concepts and, at the same time, apply these concepts in home economics…

  18. Energy-Storage Modules for Active Solar Heating and Cooling

    NASA Technical Reports Server (NTRS)

    Parker, J. C.

    1982-01-01

    34 page report describes a melting salt hydrate that stores 12 times as much heat as rocks and other heavy materials. Energy is stored mostly as latent heat; that is, heat that can be stored and recovered without any significant change in temperature. Report also describes development, evaluation and testing of permanently sealed modules containing salt hydrate mixture.

  19. Polyphosphate - an ancient energy source and active metabolic regulator

    PubMed Central

    2011-01-01

    There are a several molecules on Earth that effectively store energy within their covalent bonds, and one of these energy-rich molecules is polyphosphate. In microbial cells, polyphosphate granules are synthesised for both energy and phosphate storage and are degraded to produce nucleotide triphosphate or phosphate. Energy released from these energetic carriers is used by the cell for production of all vital molecules such as amino acids, nucleobases, sugars and lipids. Polyphosphate chains directly regulate some processes in the cell and are used as phosphate donors in gene regulation. These two processes, energetic metabolism and regulation, are orchestrated by polyphosphate kinases. Polyphosphate kinases (PPKs) can currently be categorized into three groups (PPK1, PPK2 and PPK3) according their functionality; they can also be divided into three groups according their homology (EcPPK1, PaPPK2 and ScVTC). This review discusses historical information, similarities and differences, biochemical characteristics, roles in stress response regulation and possible applications in the biotechnology industry of these enzymes. At the end of the review, a hypothesis is discussed in view of synthetic biology applications that states polyphosphate and calcium-rich organelles have endosymbiotic origins from ancient protocells that metabolized polyphosphate. PMID:21816086

  20. High energy physics division semiannual report of research activities

    SciTech Connect

    Schoessow, P.; Moonier, P.; Talaga, R.; Wagner, R. )

    1991-08-01

    This report describes the research conducted in the High Energy Physics Division of Argonne National Laboratory during the period of January 1, 1991--June 30, 1991. Topics covered here include experimental and theoretical particle physics, advanced accelerator physics, detector development, and experimental facilities research. Lists of division publications and colloquia are included.

  1. Logistic distributed activation energy model--Part 1: Derivation and numerical parametric study.

    PubMed

    Cai, Junmeng; Jin, Chuan; Yang, Songyuan; Chen, Yong

    2011-01-01

    A new distributed activation energy model is presented using the logistic distribution to mathematically represent the pyrolysis kinetics of complex solid fuels. A numerical parametric study of the logistic distributed activation energy model is conducted to evaluate the influences of the model parameters on the numerical results of the model. The parameters studied include the heating rate, reaction order, frequency factor, mean of the logistic activation energy distribution, standard deviation of the logistic activation energy distribution. The parametric study addresses the dependence on the forms of the calculated α-T and dα/dT-T curves (α: reaction conversion, T: temperature). The study results would be very helpful to the application of the logistic distributed activation energy model, which is the main subject of the next part of this series.

  2. Concept of variable activation energy and its validity in nonisothermal kinetics.

    PubMed

    Tan, Guanglei; Wang, Qi; Zheng, Hongxia; Zhao, Wei; Zhang, Song; Liu, Zhongsuo

    2011-06-09

    The concept of variable activation energy in solid-state kinetics under nonisothermal conditions has been suffering from doubt and controversy. Rate equations of nonisothermal kinetics of solid decomposition, which involve the factors of thermodynamics conditions, pressure of gaseous product, structure parameters of solid, and/or extent of conversion, are derived from the models of the interface reaction, the diffusion of gaseous product, and the nuclei growth of the solid product, respectively. The definition of the validity function in the rate equations represents the influence of the factors on the reaction rate. A function of variable activation energy depending on the validity function is also developed. The changing trend and degree of activation energy are extrapolated from the function of variable activation energy and based on the data of nonisothermal thermal decomposition of calcium carbonate. It is shown that the concept of variable activation energy is meaningfully applicable to solid-state reactions under nonisothermal conditions.

  3. How Much Energy Can Be Stored in Solar Active Region Magnetic Fields?

    NASA Astrophysics Data System (ADS)

    Linker, J.; Downs, C.; Torok, T.; Titov, V. S.; Lionello, R.; Mikic, Z.; Riley, P.

    2015-12-01

    Major solar eruptions such as X-class flares and very fast coronal mass ejections usually originate in active regions on the Sun. The energy that powers these events is believed to be stored as free magnetic energy (energy above the potential field state) prior to eruption. While coronal magnetic fields are not in general force-free, active regions have very strong magnetic fields and at low coronal heights the plasma beta is therefore very small, making the field (in equilibrium) essentially force-free. The Aly-Sturrock theorem shows that the energy of a fully force-free field cannot exceed the energy of the so-called open field. If the theorem holds, this places an upper limit on the amount of free energy that can be stored: the maximum free energy (MFE) is the difference between the open field energy and the potential field energy of the active region. In thermodynamic MHD simulations of a major eruption (the July 14, 2000 'Bastille' day event) and a modest event (February 13, 2009, we have found that the MFE indeed bounds the energy stored prior to eruption. We compute the MFE for major eruptive events in cycles 23 and 24 to investigate the maximum amount of energy that can be stored in solar active regions.Research supported by AFOSR, NASA, and NSF.

  4. Front Range Infrastructure Resources Project; energy resources activities

    USGS Publications Warehouse

    ,

    1998-01-01

    Oil, natural gas, and coal (energy resources) have been produced from rocks in the Front Range of Colorado and Wyoming for more than a century, and significant quantities of oil and gas continue to be developed in the study area of the U.S. Geological Survey (USGS) Front Range Infrastructure Resources Project (fig. 1). As an infrastructure resource, energy resources helped to fuel past development of (1) urban areas in the Front Range as well as (2) some of the manufacturing and mining upon which the urban centers were built and thrived. At present, much of the oil and gas extracted from rocks beneath the Front Range urban corridor is used locally; the people living in the urban area provide a need and viable marketplace for these commodities.

  5. Technology trends, energy prices affect worldwide rig activity

    SciTech Connect

    Rappold, K.

    1995-09-25

    The major worldwide offshore rig markets have improved slightly this year, while the onshore markets generally lagged slightly. Offshore rig utilization rates have remained strong worldwide, with some areas reaching nearly 100%. Total worldwide offshore rig (jack ups, semisubmersible, drillships, submersibles, and barges) utilization was about 86%. Offshore drilling activity is driven primarily by oil and natural gas price expectations. Natural gas prices tend to drive North American offshore drilling activity, including the shallow waters in the Gulf of Mexico. International offshore drilling activity and deepwater projects in the Gulf of Mexico are more closely tied to oil prices. The paper discusses US rig count, directional drilling activity, jack up rig demand, semisubmersibles demand, rig replacement costs, and new construction.

  6. Comparative evaluation of features and techniques for identifying activity type and estimating energy cost from accelerometer data.

    PubMed

    Kate, Rohit J; Swartz, Ann M; Welch, Whitney A; Strath, Scott J

    2016-03-01

    Wearable accelerometers can be used to objectively assess physical activity. However, the accuracy of this assessment depends on the underlying method used to process the time series data obtained from accelerometers. Several methods have been proposed that use this data to identify the type of physical activity and estimate its energy cost. Most of the newer methods employ some machine learning technique along with suitable features to represent the time series data. This paper experimentally compares several of these techniques and features on a large dataset of 146 subjects doing eight different physical activities wearing an accelerometer on the hip. Besides features based on statistics, distance based features and simple discrete features straight from the time series were also evaluated. On the physical activity type identification task, the results show that using more features significantly improve results. Choice of machine learning technique was also found to be important. However, on the energy cost estimation task, choice of features and machine learning technique were found to be less influential. On that task, separate energy cost estimation models trained specifically for each type of physical activity were found to be more accurate than a single model trained for all types of physical activities.

  7. Low effective activation energies for oxygen release from metal oxides: evidence for mass-transfer limits at high heating rates.

    PubMed

    Jian, Guoqiang; Zhou, Lei; Piekiel, Nicholas W; Zachariah, Michael R

    2014-06-06

    Oxygen release from metal oxides at high temperatures is relevant to many thermally activated chemical processes, including chemical-looping combustion, solar thermochemical cycles and energetic thermite reactions. In this study, we evaluated the thermal decomposition of nanosized metal oxides under rapid heating (~10(5) K s(-1)) with time-resolved mass spectrometry. We found that the effective activation-energy values that were obtained using the Flynn-Wall-Ozawa isoconversional method are much lower than the values found at low heating rates, indicating that oxygen transport might be rate-determining at a high heating rate.

  8. Determining Linac Beam Energy from C-11/O-15 Activity Ratios in Polymers

    NASA Astrophysics Data System (ADS)

    Cardman, Ryan; Shepherd, Matthew

    2017-01-01

    A method for precisely measuring the beam energy of 20-25 MeV electron linear accelerator was developed. Polyoxymethylene (Delrin) and poly(methyl methacrylate) (acrylic) samples were irradiated with an electron linac at several energy settings of the accelerator simultaneously producing C-11 and O-15 via photonuclear reactions within each of the polymers. Using gamma-ray spectroscopy the activity ratios of C-11/O-15 were measured by analyzing the decay of activity vs. time. The C-11/O-15 ratio exhibits an energy dependence due to differences in the production cross section vs. energy. The observed dependence can be matched to predictions of the activity ratio vs. energy, developed from GEANT4 Monte Carlo models of an electromagnetic shower and knowledge of the cross sections, in order to determine the energy of the beam at a sub-MeV level of precision. National Science Foundation Research Experience for Undergraduates.

  9. Lactate Effectively Covers Energy Demands during Neuronal Network Activity in Neonatal Hippocampal Slices

    PubMed Central

    Ivanov, Anton; Mukhtarov, Marat; Bregestovski, Piotr; Zilberter, Yuri

    2011-01-01

    Although numerous experimental data indicate that lactate is efficiently used for energy by the mature brain, the direct measurements of energy metabolism parameters during neuronal network activity in early postnatal development have not been performed. Therefore, the role of lactate in the energy metabolism of neurons at this age remains unclear. In this study, we monitored field potentials and contents of oxygen and NAD(P)H in correlation with oxidative metabolism during intense network activity in the CA1 hippocampal region of neonatal brain slices. We show that in the presence of glucose, lactate is effectively utilized as an energy substrate, causing an augmentation of oxidative metabolism. Moreover, in the absence of glucose lactate is fully capable of maintaining synaptic function. Therefore, during network activity in neonatal slices, lactate can be an efficient energy substrate capable of sustaining and enhancing aerobic energy metabolism. PMID:21602909

  10. An examination of the differences between two methods of estimating energy expenditure in resistance training activities.

    PubMed

    Vezina, Jesse W; Der Ananian, Cheryl A; Campbell, Kathryn D; Meckes, Nathanael; Ainsworth, Barbara E

    2014-04-01

    To date, few studies have looked at the energy expenditure (EE) of individual resistance training (RT) exercises. The purpose of this study was to evaluate the EE of 4 modes of RT (push-ups, curl-ups, pull-ups, and lunges) using 2 different calculation methods for estimating EE. Twelve healthy men with a minimum of 1 year of RT experience were randomly assigned to an RT circuit. Each circuit contained the 4 RT exercises in a specified order. The participants completed 3 trials of their assigned circuit during one visit to the laboratory. Oxygen consumption was measured continuously throughout the trial using indirect calorimetry. Two different calculation methods were applied to estimate EE. Using the traditional method (TEC), we estimated EE by calculating the average oxygen consumption recorded during each activity. Using the second, nontraditional method (NEC), we estimated EE by calculating the average oxygen consumption recorded during the recovery period. Independent T-tests were used to evaluate mean EE differences between the 2 methods. Estimates of EE obtained from the NEC were significantly higher for all the 4 activities (p < 0.001). Using the NEC, 3 of the 4 activities were classified as vigorous intensity (push-ups: 6.91 metabolic equivalents (METs); lunges: 7.52 METs; and pull-ups: 8.03 METs), whereas none were classified as vigorous using the TEC. Findings suggest that the methods we use to calculate the EE of anaerobic activities significantly affect EE estimates. Using the TEC may underestimate actual EE of anaerobic activities.

  11. Real-time detection of cellular death receptor-4 activation by fluorescence resonance energy transfer.

    PubMed

    Dereli-Korkut, Zeynep; Gandhok, Harmeet; Zeng, Ling Ge; Waqas, Sidra; Jiang, Xuejun; Wang, Sihong

    2013-05-01

    Targeted therapy involving the activation of death receptors DR4 and/or DR5 by its ligand, TRAIL, can selectively induce apoptosis in certain tumor cells. In order to profile the dynamic activation or trimerization of TRAIL-DR4 in live cells in real-time, the development of an apoptosis reporter cell line is essential. Fluorescence resonance energy transfer (FRET) technology via a FRET pair, cyan fluorescence protein (CFP) and yellow fluorescence protein (YFP), was used in this study. DR4-CFP and DR4-YFP were stably expressed in human lung cancer PC9 cells. Flow cytometer sorting and limited dilution coupled with fluorescence microscopy were used to select a monoclonal reporter cell line with high and compatible expression levels of DR4-CFP and DR4-YFP. FRET experiments were conducted and FRET efficiencies were monitored according to the Siegel's YFP photobleaching FRET protocol. Upon TRAIL induction a significant increase in FRET efficiencies from 5% to 9% demonstrated the ability of the DR4-CFP/YFP reporter cell line in monitoring the dynamic activation of TRAIL pathways. 3D reconstructed confocal images of DR4-CFP/YFP reporter cells exhibited a colocalized expression of DR4-CFP and DR4-YFP mainly on cell membranes. FRET results obtained during this study complements the use of epi-fluorescence microscopy for FRET analysis. The real-time FRET analysis allows the dynamic profiling of the activation of TRAIL pathways by using the time-lapse fluorescence microscopy. Therefore, DR4-CFP/YFP PC9 reporter cells along with FRET technology can be used as a tool for anti-cancer drug screening to identify compounds that are capable of activating TRAIL pathways.

  12. Verification of energy's role as a determinant of US economic activity

    SciTech Connect

    Santini, D.J.

    1987-10-01

    A series of single-equation dynamic regression models are constructed to test the hypotheses that both ''thermodynamic'' and economic-efficiency (t-efficiency and e-efficiency, respectively) configurations of lagged energy variables are statistically informative separately and jointly about subsequent changes in real gross national product (GNP) per capita and in unemployment rate. Separately, t-efficiency is based on quantity of energy used per unit of GNP, while e-efficiency is based on real price of tested energy variables. Used jointly, the two measure real energy cost per unit of real GNP. Tested subperiods are within the 1890-1985 period. Macroeconomic activity is found to be much less informative about energy variables that are energy variables about macroeconomic activity. One-way tests are conducted in which the informativeness of major e-efficiency (wholesale price) variables and budget-share variables about subsequent macroeconomic activity are compared to the informativeness of the e-efficiency energy variable and the combined e- and t-efficiencies energy variable respectively. The energy variables are found to represent the only major category of expenditure whose statistical tests for informativeness about subsequent macroeconomic activity result in coefficient signs that consistently imply a statistically significant negative effect on subsequent macroeconomic activity in the full 1890-1985 period. 64 refs., 14 tabs.

  13. Nuclear Energy Gradients for Internally Contracted Complete Active Space Second-Order Perturbation Theory: Multistate Extensions.

    PubMed

    Vlaisavljevich, Bess; Shiozaki, Toru

    2016-08-09

    We report the development of the theory and computer program for analytical nuclear energy gradients for (extended) multistate complete active space perturbation theory (CASPT2) with full internal contraction. The vertical shifts are also considered in this work. This is an extension of the fully internally contracted CASPT2 nuclear gradient program recently developed for a state-specific variant by us [MacLeod and Shiozaki, J. Chem. Phys. 2015, 142, 051103]; in this extension, the so-called λ equation is solved to account for the variation of the multistate CASPT2 energies with respect to the change in the amplitudes obtained in the preceding state-specific CASPT2 calculations, and the Z vector equations are modified accordingly. The program is parallelized using the MPI3 remote memory access protocol that allows us to perform efficient one-sided communication. The optimized geometries of the ground and excited states of a copper corrole and benzophenone are presented as numerical examples. The code is publicly available under the GNU General Public License.

  14. TiO 2 (B)/activated carbon non-aqueous hybrid system for energy storage

    NASA Astrophysics Data System (ADS)

    Brousse, Thierry; Marchand, René; Taberna, Pierre-Louis; Simon, Patrice

    TiO 2 (B) has been investigated as a possible candidate to replace Li 4Ti 5O 12 as a negative electrode for Li-ion battery. The starting compound was synthesized by a simple solid state reaction followed by hydrolysis. Long term stability of the TiO 2 (B) electrode can be obtained by limiting lithium intercalation between 0.25 and 0.35 Li + per unit formula. High cycling rates (up to 24 C) have been used without noticeable degradation of the electrode. A non-aqueous hybrid energy storage device using TiO 2 (B) as the negative electrode and activated carbon as the positive was assembled. The maximum hybrid cell voltage can be set between 2.75 V and 3.5 V. The cells exhibit energy densities between 45 W kg -1 and 80 W kg -1 with power densities in the range 240-420 W kg -1 which is compatible with a fast charging/discharging storage device, intermediate between electrochemical double layer capacitor and Li-ion batteries.

  15. Obscured flat spectrum radio active galactic nuclei as sources of high-energy neutrinos

    NASA Astrophysics Data System (ADS)

    Maggi, G.; Buitink, S.; Correa, P.; de Vries, K. D.; Gentile, G.; Tavares, J. León; Scholten, O.; van Eijndhoven, N.; Vereecken, M.; Winchen, T.

    2016-11-01

    Active galactic nuclei (AGN) are believed to be one of the main source candidates for the high-energy (TeV-PeV) cosmic neutrino flux recently discovered by the IceCube neutrino observatory. Nevertheless, several correlation studies between AGN and the cosmic neutrinos detected by IceCube show no significance. Therefore, in this article we consider a specific subclass of AGN for which an increased neutrino production is expected. This subclass contains AGN for which their high-energy jet is pointing toward Earth. Furthermore, we impose the condition that the jet is obscured by gas or dust surrounding the AGN. A method is presented to determine the total column density of the obscuring medium, which is probed by determining the relative x-ray attenuation with respect to the radio flux as obtained from the AGN spectrum. The total column density allows us to probe the interaction of the jet with the surrounding matter, which leads to additional neutrino production. Finally, starting from two different source catalogs, this method is applied to specify a sample of low redshift radio galaxies for which an increased neutrino production is expected.

  16. ECUT: Energy Conversion and Utilization Technologies program - Biocatalysis research activity

    NASA Technical Reports Server (NTRS)

    Wilcox, R.

    1984-01-01

    The activities of the Biocatalysis Research Activity are organized into the Biocatalysis and Molecular Modeling work elements and a supporting planning and analysis function. In the Biocatalysis work element, progress is made in developing a method for stabilizing genetically engineered traits in microorganisms, refining a technique for monitoring cells that are genetically engineered, and identifying strains of fungi for highly efficient preprocessing of biomass for optimizing the efficiency of bioreactors. In the Molecular Modeling work element, a preliminary model of the behavior of enzymes is developed. A preliminary investigation of the potential for synthesizing enzymes for use in electrochemical processes is completed. Contact with industry and universities is made to define key biocatalysis technical issues and to broaden the range of potential participants in the activity. Analyses are conducted to identify and evaluate potential concepts for future research funding.

  17. ECUT: Energy Conversion and Utilization Technologies program - Biocatalysis research activity

    NASA Astrophysics Data System (ADS)

    Wilcox, R.

    1984-04-01

    The activities of the Biocatalysis Research Activity are organized into the Biocatalysis and Molecular Modeling work elements and a supporting planning and analysis function. In the Biocatalysis work element, progress is made in developing a method for stabilizing genetically engineered traits in microorganisms, refining a technique for monitoring cells that are genetically engineered, and identifying strains of fungi for highly efficient preprocessing of biomass for optimizing the efficiency of bioreactors. In the Molecular Modeling work element, a preliminary model of the behavior of enzymes is developed. A preliminary investigation of the potential for synthesizing enzymes for use in electrochemical processes is completed. Contact with industry and universities is made to define key biocatalysis technical issues and to broaden the range of potential participants in the activity. Analyses are conducted to identify and evaluate potential concepts for future research funding.

  18. Influence of intense physical activity on energy balance and body fatness.

    PubMed

    Tremblay, A; Doucet, E

    1999-02-01

    The reduced contribution of physical activity to daily energy expenditure and the accessibility to high-fat foods have put an excessive burden on energy balance, resulting in an increase in the prevalence of obesity throughout the world. In this context, fat gain can be seen as a natural adaptation to deal with a fattening lifestyle, since the hormonal adaptations that accompany fat gain favour the readjustment of energy expenditure to energy intake. Intense physical activity would also seem to facilitate the regulation of energy balance, since it increases the energy cost of exercise, increases post-exercise energy expenditure and the potential of skeletal muscles to utilize lipids, and also favours a decrease in post-exercise intake. Moreover, the effects of intense exercise seem to be mediated by an activation of sympathetic nervous system activity that seems to be specific to skeletal muscle. It is also important to manipulate macronutrient composition in order to reduce fat intake, because unhealthy food habits can favour overfeeding and thus overcome the energy deficit caused by regular physical activity. Under free-living conditions, the combination of vigorous activity and healthy food practices can amount to a substantial weight loss which is comparable with that of other non-surgical approaches to treat obesity.

  19. Gas Chromatographic-Mass Spectrometric Analysis of Volatiles Obtained by Four Different Techniques from Salvia rosifolia Sm. and Evaluation for Biological Activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Volatile constituents from the aerial parts of Salvia rosifolia Sm. (Lamiaceae), endemic to Turkey, were obtained by four different isolation techniques and then analyzed by gas chromatography (GC/FID) and gas chromatography – mass spectrometry (GC/MS) methods. Also in scope of the present work, the...

  20. Nanocomposites of C3N4 with Layers of MoS2 and Nitrogenated RGO, Obtained by Covalent Cross-linking: Synthesis, Characterization and HER Activity.

    PubMed

    Pramoda, K; Gupta, Uttam; Chhetri, Manjeet; Bandyopadhyay, Arkamita; Pati, Swapan K; Rao, Chintamani Nagesa Ramachandra

    2017-03-07

    Generation of hydrogen by photochemical, electrochemical and other means is a vital area of research today and a variety of materials has been explored as catalysts for this purpose. C3N4, MoS2 and nitrogenated RGO (NRGO) are some of the important catalytic materials investigated for the HER reaction but the observed catalytic activities are somewhat marginal. Prompted by preliminary reports that covalent cross-linking of 2D materials to generate hetero assemblies or nanocomposites may have beneficial effect on the catalytic activity, we have synthesized nanocomposites wherein C3N4 is covalently bonded to MoS2 or NRGO nanosheets. The photochemical HER activity of the C3N4-MoS2 nanocomposite is found to be remarkable with a activity of 12778 µmoles h-1g-1 and a TOF of 2.35 h-1. The physical mixture of C3N4 and MoS2, on the other hand, does not exhibit notable catalytic activity. Encouraged by this result, we have studied electrochemical HER activity of these composites as well. C3N4-MoS2 shows superior activity relative to a physical mixture of MoS2 and C3N4. DFT calculations have been carried out to understand the HER activity of the nanocomposites. Charge-transfer between the components and greater planarity of cross-linked layers are important causes of the superior catalytic activity of the nanocomposites. Covalent linking of such 2D materials appears to be a worthwhile strategy for catalysis and other applications.