Generalized surface tension bounds in vacuum decay
Masoumi, Ali; Paban, Sonia; Weinberg, Erick J.
2018-02-01
Coleman and De Luccia (CDL) showed that gravitational effects can prevent the decay by bubble nucleation of a Minkowski or AdS false vacuum. In their thin-wall approximation this happens whenever the surface tension in the bubble wall exceeds an upper bound proportional to the difference of the square roots of the true and false vacuum energy densities. Recently it was shown that there is another type of thin-wall regime that differs from that of CDL in that the radius of curvature grows substantially as one moves through the wall. Not only does the CDL derivation of the bound fail in this case, but also its very formulation becomes ambiguous because the surface tension is not well defined. We propose a definition of the surface tension and show that it obeys a bound similar in form to that of the CDL case. We then show that both thin-wall bounds are special cases of a more general bound that is satisfied for all bounce solutions with Minkowski or AdS false vacua. We discuss the limit where the parameters of the theory attain critical values and the bound is saturated. The bounce solution then disappears and a static planar domain wall solution appears in its stead. The scalar field potential then is of the form expected in supergravity, but this is only guaranteed along the trajectory in field space traced out by the bounce.
Surface-bound states in nanodiamonds
Han, Peng; Antonov, Denis; Wrachtrup, Jörg; Bester, Gabriel
2017-05-01
We show via ab initio calculations and an electrostatic model that the notoriously low, but positive, electron affinity of bulk diamond becomes negative for hydrogen passivated nanodiamonds and argue that this peculiar situation (type-II offset with a vacuum level at nearly midgap) and the three further conditions: (i) a surface dipole with positive charge on the outside layer, (ii) a spherical symmetry, and (iii) a dielectric mismatch at the surface, results in the emergence of a peculiar type of surface state localized just outside the nanodiamond. These states are referred to as "surface-bound states" and have consequently a strong environmental sensitivity. These type of states should exist in any nanostructure with negative electron affinity. We further quantify the band offsets of different type of nanostructures as well as the exciton binding energy and contrast the results with results for "conventional" silicon quantum dots.
BION web server: predicting non-specifically bound surface ions.
Petukh, Marharyta; Kimmet, Taylor; Alexov, Emil
2013-03-15
Ions are essential component of the cell and frequently are found bound to various macromolecules, in particular to proteins. A binding of an ion to a protein greatly affects protein's biophysical characteristics and needs to be taken into account in any modeling approach. However, ion's bounded positions cannot be easily revealed experimentally, especially if they are loosely bound to macromolecular surface. Here, we report a web server, the BION web server, which addresses the demand for tools of predicting surface bound ions, for which specific interactions are not crucial; thus, they are difficult to predict. The BION is easy to use web server that requires only coordinate file to be inputted, and the user is provided with various, but easy to navigate, options. The coordinate file with predicted bound ions is displayed on the output and is available for download.
Subgap in the Surface Bound States Spectrum of Superfluid ^3 He-B with Rough Surface
Nagato, Y.; Higashitani, S.; Nagai, K.
2017-12-01
The subgap structure in the surface bound states spectrum of superfluid ^3 He-B with rough surface is discussed. The subgap is formed by the level repulsion between the surface bound state and the continuum states in the course of multiple scattering by the surface roughness. We show that the level repulsion is originated from the nature of the wave function of the surface bound state that is now recognized as Majorana fermion. We study the superfluid ^3 He-B with a rough surface and in a magnetic field perpendicular to the surface using the quasi-classical Green function together with a random S-matrix model. We calculate the self-consistent order parameters, the spin polarization density and the surface density of states. It is shown that the subgap is found also in a magnetic field perpendicular to the surface. The magnetic field dependence of the transverse acoustic impedance is also discussed.
Surface plasmon oscillations in a semi-bounded semiconductor plasma
M, SHAHMANSOURI; A, P. MISRA
2018-02-01
We study the dispersion properties of surface plasmon (SP) oscillations in a semi-bounded semiconductor plasma with the effects of the Coulomb exchange (CE) force associated with the spin polarization of electrons and holes as well as the effects of the Fermi degenerate pressure and the quantum Bohm potential. Starting from a quantum hydrodynamic model coupled to the Poisson equation, we derive the general dispersion relation for surface plasma waves. Previous results in this context are recovered. The dispersion properties of the surface waves are analyzed in some particular cases of interest and the relative influence of the quantum forces on these waves are also studied for a nano-sized GaAs semiconductor plasma. It is found that the CE effects significantly modify the behaviors of the SP waves. The present results are applicable to understand the propagation characteristics of surface waves in solid density plasmas.
Determining the limit of detection of surface bound antibody.
Madiona, Robert M T; Welch, Nicholas G; Scoble, Judith A; Muir, Benjamin W; Pigram, Paul J
2017-08-11
Determination of a limit of detection (LoD) for surface bound antibodies is crucial for the development and deployment of sensitive bioassays. The measurement of very low concentrations of surface bound antibodies is also important in the manufacturing of pharmaceutical products such as antibody-conjugated pharmaceuticals. Low concentrations are required to avoid an immune response from the target host. Enzyme-linked immunosorbent assay (ELISA), x-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were used to determine the LoD for the surface bound antibody (antiepidermal growth factor receptor antibody) on silicon substrates. Antibody solution concentrations between 10 μg/ml and 1 ng/ml and a control (antibody-free buffer solution) were employed, and the detection performance of each technique was compared. For this system, the ELISA LoD was 100 ng/ml and the XPS LoD was 1 μg/ml, corresponding to an estimated surface concentration of 49 ± 7 ng/cm 2 using a 1 μg/ml solution. Due to the multivariate complexity of ToF-SIMS data, analysis was carried out using three different methods, peak ratio calculations, principal component analysis, and artificial neural network analysis. The use of multivariate analysis with this dataset offers an unbiased analytical approach based on the peaks selected from ToF-SIMS data. The results estimate a ToF-SIMS LoD between applied antibody concentrations of 10 and 100 ng/mL. For surface bound antibodies on a silicon substrate, the LoD is below an estimated surface concentration of 49 ng/cm 2 . The authors have determined the LoD for this system using ELISA, XPS, and ToF-SIMS with multivariate analyses, with ToF-SIMS offering an order of magnitude better detection over ELISA and 2 orders of magnitude better detection over XPS.
Nanostructures and dynamics of macromolecules bound to attractive filler surfaces
Koga, Tad; Barkley, Deborah; Jiang, Naisheng; Endoh, Maya; Masui, Tomomi; Kishimoto, Hiroyuki; Nagao, Michihiro; Satija, Sushil; Taniguchi, Takashi
We report in-situ nanostructures and dynamics of polybutadiene (PB) chains bound to carbon black (CB) fillers (the so-called ``bound polymer layer (BPL)'') in a good solvent. The BPL on the CB fillers were extracted by solvent leaching of a CB-filled PB compound and subsequently dispersed in deuterated toluene to label the BPL for small-angle neutron scattering and neutron spin echo techniques. Intriguingly, the results demonstrate that the BPL is composed of two regions regardless of molecular weights of PB: the inner unswollen region of ~ 0.5 nm thick and outer swollen region where the polymer chains display a parabolic profile with a diffuse tail. This two-layer formation on the filler surface is similar to that reported for polymer chains adsorbed on planar substrates from melts. In addition, the results show that the dynamics of the swollen bound chains can be explained by the so-called ``breathing mode'' and is generalized with the thickness of the swollen BPL. Furthermore, we will discuss how the breathing collective dynamics is affected by the presence of polymer chains in a matrix solution. We acknowledge the financial support from NSF Grant No. CMMI-1332499.
Error bounds for surface area estimators based on Crofton's formula
DEFF Research Database (Denmark)
Kiderlen, Markus; Meschenmoser, Daniel
2009-01-01
According to Crofton’s formula, the surface area S(A) of a sufficiently regular compact set A in R^d is proportional to the mean of all total projections pA (u) on a linear hyperplane with normal u, uniformly averaged over all unit vectors u. In applications, pA (u) is only measured in k directio...... in the sense that the relative error of the surface area estimator is very close to the minimal error....... and the mean is approximated by a finite weighted sum S(A) of the total projections in these directions. The choice of the weights depends on the selected quadrature rule. We define an associated zonotope Z (depending only on the projection directions and the quadrature rule), and show that the relative error...... S (A)/S (A) is bounded from below by the inradius of Z and from above by the circumradius of Z. Applying a strengthened isoperimetric inequality due to Bonnesen, we show that the rectangular quadrature rule does not give the best possible error bounds for d = 2. In addition, we derive asymptotic...
Sea level: measuring the bounding surfaces of the ocean.
Tamisiea, Mark E; Hughes, Chris W; Williams, Simon D P; Bingley, Richard M
2014-09-28
The practical need to understand sea level along the coasts, such as for safe navigation given the spatially variable tides, has resulted in tide gauge observations having the distinction of being some of the longest instrumental ocean records. Archives of these records, along with geological constraints, have allowed us to identify the century-scale rise in global sea level. Additional data sources, particularly satellite altimetry missions, have helped us to better identify the rates and causes of sea-level rise and the mechanisms leading to spatial variability in the observed rates. Analysis of all of the data reveals the need for long-term and stable observation systems to assess accurately the regional changes as well as to improve our ability to estimate future changes in sea level. While information from many scientific disciplines is needed to understand sea-level change, this review focuses on contributions from geodesy and the role of the ocean's bounding surfaces: the sea surface and the Earth's crust. © 2014 The Author(s) Published by the Royal Society. All rights reserved.
Rigorous bounds on buoyancy flux in surface driven flows
Caulfield, C. P.
2004-11-01
Stably stratified shear flows, where both the velocity and density vary with height, are common in environmentally and geophysically relevant flows. An understanding of constraints on mixing processes is essential for an improved parameterization of geophysical turbulence, in particular for appropriate modelling of the budgets of heat, salinity and momentum in larger scale models. Flows that are principally driven by surface-localized stresses (e.g. caused by wind) are particularly prevalent in geophysical flows. In this talk, I will derive rigorous bounds on the long-time averaged buoyancy flux for a class of such flows, using the background method developed by Doering & Constantin. Interestingly, flows that maximize the buoyancy flux can be directly related to laminar flows with stronger forcing. This is qualitatively different from other stratified mixing problems, for example in stratified plane Couette flow. This result suggests that quasi-laminar mixing, which is typically much more efficient than strongly turbulent mixing, may be the dominant process by which irreversible changes in density occur within such surface driven flows.
Sea level: measuring the bounding surfaces of the ocean
Tamisiea, Mark E.; Hughes, Chris W.; Williams, Simon D. P.; Bingley, Richard M.
2014-01-01
The practical need to understand sea level along the coasts, such as for safe navigation given the spatially variable tides, has resulted in tide gauge observations having the distinction of being some of the longest instrumental ocean records. Archives of these records, along with geological constraints, have allowed us to identify the century-scale rise in global sea level. Additional data sources, particularly satellite altimetry missions, have helped us to better identify the rates and causes of sea-level rise and the mechanisms leading to spatial variability in the observed rates. Analysis of all of the data reveals the need for long-term and stable observation systems to assess accurately the regional changes as well as to improve our ability to estimate future changes in sea level. While information from many scientific disciplines is needed to understand sea-level change, this review focuses on contributions from geodesy and the role of the ocean's bounding surfaces: the sea surface and the Earth's crust. PMID:25157196
International Nuclear Information System (INIS)
Macdonald, Thomas; Gibson, Christopher T.; Constantopoulos, Kristina; Shapter, Joseph G.; Ellis, Amanda V.
2012-01-01
Here we demonstrate the covalent attachment of vertically aligned (VA) acid treated single-walled carbon nanotubes (SWCNTs) onto a silicon substrate via dicyclohexylcarbodiimide (DCC) coupling chemistry. Subsequently, the pendant carboxyl moieties on the sidewalls of the VA-SWCNTs were derivatized to acyl chlorides, and then finally to bis(dithioester) moieties using a magnesium chloride dithiobenzoate salt. The bis(dithioester) moieties were then successfully shown to act as a chain transfer agent (CTA) in the reversible addition fragmentation chain transfer (RAFT) polymerization of styrene in a surface initiated “grafting-from” process from the VA-SWCNT surface. Atomic force microscopy (AFM) verified vertical alignment of the SWCNTs and the maintenance thereof throughout the synthesis process. Finally, Raman scattering spectroscopy and AFM confirmed polystyrene functionalization.
Inhibition of surface bound carbonate stabilization of tetragonal zirconia
DEFF Research Database (Denmark)
Nielsen, Mette Skovgaard; Almdal, Kristoffer; Lelieveld, A. van
2011-01-01
Water is known to initiate a tetragonal to monoclinic phase transformation in zirconia particles. Carbonates on the zirconia surface react with water molecules and hence reduce the transformation rate. This study investigates the possibility of inhibition of the reaction between surface carbonates...... and water in order to increase the transformation rate in the zirconia crystals. It was found possible to limit the reaction by reacting the surface carbonates with alcohols, a thiol and a primary amide prior to reaction with water. It was also concluded that di- and trialcohols are able to stabilize...
Surface-bound microgels - From physicochemical properties to biomedical applications
DEFF Research Database (Denmark)
Nyström, Lina; Malmsten, Martin
2016-01-01
Microgels offer robust and facile approaches for surface modification, as well as opportunities to introduce biological functionality by loading such structures with bioactive agents, e.g., in the context of drug delivery, functional biomaterials, and biosensors. As such, they provide a versatile...
Chen, S.; Al-Muntasheri, G.; Abousleiman, Y. N.
2014-12-01
The critical state concept based bounding surface model is one of the most widely used elastoplastic constitutive models for geomaterials, attributed mainly to its essential feature of allowing plastic deformation to occur for stress points within the bounding surface and thus the capability to represent the realistic non-recoverable behaviour of soils and rocks observed under the cyclic loading. This paper develops an implicit integration algorithm for the bounding surface model, using the standard return mapping approach (elastic predictor-plastic corrector), to obtain the updated stresses for the given strain increments. The formulation of the constitutive integration requires the derivation of a supplementary differential equation to describe the evolution of a key variable, i.e., the ratio between the image stress and the current stress quantities. It is essentially an extension of the integration scheme presented in an earlier work used for the simple bounding surface version of modified Cam Clay associated with a substantially simplified hardening rule. The integration algorithm for the bounding surface model is implemented into the finite element analysis commercial program, ABAQUS, through the material interface of UMAT (user defined material subroutine), and then used for the analysis of wellbore stability problem. The predictions from the ABAQUS simulations are generally in excellent agreement with the available analytical solutions, thus demonstrating the accuracy and robustness of the proposed integration scheme.
NEXAFS characterization of DNA components and molecular-orientation of surface-bound DNA oligomers
International Nuclear Information System (INIS)
Samuel, Newton T.; Lee, C.-Y.; Gamble, Lara J.; Fischer, Daniel A.; Castner, David G.
2006-01-01
Single stranded DNA oligomers (ssDNA) immobilized onto solid surfaces forms the basis for several biotechnological applications such as DNA microarrays, affinity separations, and biosensors. Surface structure of Surface-bound oligomers is expected to significantly influence their biological activity and interactions with the environment. In this study near-edge X-ray absorption fine structure spectroscopy (NEXAFS) is used to characterize the components of DNA (nucleobases, nucleotides and nucleosides) and the orientation information of surface-bound ssDNA. The K-edges of carbon, nitrogen and oxygen have spectra with features that are characteristic of the different chemical species present in the nucleobases of DNA. The effect of addition of the DNA sugar and phosphate components on the NEXAFS K-edge spectra was also investigated. The polarization-dependent nitrogen K-edge NEXAFS data show significant changes for different orientations of surface bound ssDNA. These results establish NEXAFS as a powerful technique for chemical and structural characterization of surface-bound DNA oligomers
Bound and resonant surface states at the (110) surfaces of AlSb, AlAs, and AlP
International Nuclear Information System (INIS)
Beres, R.P.; Allen, R.E.; Buisson, J.P.; Bowen, M.A.; Blackwell, G.F.; Hjalmarson, H.P.; Dow, J.D.
1982-01-01
The dispersion curves E(k-bar) have been calculated for bound and resonant (110) surface states of AlSb, AlAs, and AlP. AlSb is predicted to have no surface states within the bulk fundamental band gap, but AlAs and AlP are predicted to have surface state band minima which are very near the conduction band edge, and could lie either within the gap or immediately above the edge
On the bound states of Schrodinger operators with -interactions on conical surfaces
Czech Academy of Sciences Publication Activity Database
Lotoreichik, Vladimir; Ourmieres-Bonafos, T.
2016-01-01
Roč. 41, č. 6 (2016), s. 999-1028 ISSN 0360-5302 Institutional support: RVO:61389005 Keywords : conical and hyperconical surfaces * delta-interaction * existence of bound states * Schrodinger operator * spectral asymptotics Subject RIV: BE - Theoretical Physics Impact factor: 1.608, year: 2016
In-situ observations of catalyst dynamics during surface-bound carbon nanotube nucleation
DEFF Research Database (Denmark)
Hofmann, S; Sharma, R; Du, G
2007-01-01
We present atomic-scale, video-rate environmental transmission electron microscopy and in situ time-resolved X-ray photoelectron spectroscopy of surface-bound catalytic chemical vapor deposition of single-walled carbon nanotubes and nanofibers. We observe that transition metal catalyst...
Trade-off bounds for the Pareto surface approximation in multi-criteria IMRT planning.
Serna, J I; Monz, M; Küfer, K H; Thieke, C
2009-10-21
One approach to multi-criteria IMRT planning is to automatically calculate a data set of Pareto-optimal plans for a given planning problem in a first phase, and then interactively explore the solution space and decide on the clinically best treatment plan in a second phase. The challenge of computing the plan data set is to ensure that all clinically meaningful plans are covered and that as many clinically irrelevant plans as possible are excluded to keep computation times within reasonable limits. In this work, we focus on the approximation of the clinically relevant part of the Pareto surface, the process that constitutes the first phase. It is possible that two plans on the Pareto surface have a small, clinically insignificant difference in one criterion and a significant difference in another criterion. For such cases, only the plan that is clinically clearly superior should be included into the data set. To achieve this during the Pareto surface approximation, we propose to introduce bounds that restrict the relative quality between plans, the so-called trade-off bounds. We show how to integrate these trade-off bounds into the approximation scheme and study their effects. The proposed scheme is applied to two artificial cases and one clinical case of a paraspinal tumor. For all cases, the quality of the Pareto surface approximation is measured with respect to the number of computed plans, and the range of values occurring in the approximation for different criteria is compared. Through enforcing trade-off bounds, the scheme disregards clinically irrelevant plans during the approximation. Thereby, the number of plans necessary to achieve a good approximation quality can be significantly reduced. Thus, trade-off bounds are an effective tool to focus the planning and to reduce computation time.
Trade-off bounds for the Pareto surface approximation in multi-criteria IMRT planning
International Nuclear Information System (INIS)
Serna, J I; Monz, M; Kuefer, K H; Thieke, C
2009-01-01
One approach to multi-criteria IMRT planning is to automatically calculate a data set of Pareto-optimal plans for a given planning problem in a first phase, and then interactively explore the solution space and decide on the clinically best treatment plan in a second phase. The challenge of computing the plan data set is to ensure that all clinically meaningful plans are covered and that as many clinically irrelevant plans as possible are excluded to keep computation times within reasonable limits. In this work, we focus on the approximation of the clinically relevant part of the Pareto surface, the process that constitutes the first phase. It is possible that two plans on the Pareto surface have a small, clinically insignificant difference in one criterion and a significant difference in another criterion. For such cases, only the plan that is clinically clearly superior should be included into the data set. To achieve this during the Pareto surface approximation, we propose to introduce bounds that restrict the relative quality between plans, the so-called trade-off bounds. We show how to integrate these trade-off bounds into the approximation scheme and study their effects. The proposed scheme is applied to two artificial cases and one clinical case of a paraspinal tumor. For all cases, the quality of the Pareto surface approximation is measured with respect to the number of computed plans, and the range of values occurring in the approximation for different criteria is compared. Through enforcing trade-off bounds, the scheme disregards clinically irrelevant plans during the approximation. Thereby, the number of plans necessary to achieve a good approximation quality can be significantly reduced. Thus, trade-off bounds are an effective tool to focus the planning and to reduce computation time.
Tracking a Common Surface-Bound Intermediate during CO2-to-Fuels Catalysis
2016-01-01
Rational design of selective CO2-to-fuels electrocatalysts requires direct knowledge of the electrode surface structure during turnover. Metallic Cu is the most versatile CO2-to-fuels catalyst, capable of generating a wide array of value-added products, including methane, ethylene, and ethanol. All of these products are postulated to form via a common surface-bound CO intermediate. Therefore, the kinetics and thermodynamics of CO adsorption to Cu play a central role in determining fuel-formation selectivity and efficiency, highlighting the need for direct observation of CO surface binding equilibria under catalytic conditions. Here, we synthesize nanostructured Cu films adhered to IR-transparent Si prisms, and we find that these Cu surfaces enhance IR absorption of bound molecules. Using these films as electrodes, we examine Cu-catalyzed CO2 reduction in situ via IR spectroelectrochemistry. We observe that Cu surfaces bind electrogenerated CO, derived from CO2, beginning at −0.60 V vs RHE with increasing surface population at more negative potentials. Adsorbed CO is in dynamic equilibrium with dissolved 13CO and exchanges rapidly under catalytic conditions. The CO adsorption profiles are pH independent, but adsorbed CO species undergo a reversible transformation on the surface in modestly alkaline electrolytes. These studies establish the potential, concentration, and pH dependencies of the CO surface population on Cu, which serve to maintain a pool of this vital intermediate primed for further reduction to higher order fuel products. PMID:27610413
2010-01-01
Surface-bound nucleic acid probes designed to adopt specific secondary structures are becoming increasingly important in a range of biosensing applications but remain less well characterized than traditional single-stranded probes, which are typically designed to avoid secondary structure. We report the hybridization efficiency for surface-immobilized hairpin DNA probes. Our probes are molecular beacons, carrying a 3′ dye moiety and a 5′ thiol for attachment to gold nanowires, which serve as both scaffolds for probe attachment and quenchers. Hybridization efficiency was dependent on probe surface coverage, reaching a maximum of ∼90% at intermediate coverages of (1−2) × 1012 probes/cm2 and dropping to ≤20% at higher or lower coverages. Fluorescence intensity did not track with the number of target molecules bound, and was highest for high probe coverage despite the lower bound targets per square centimeter. Backfilling with short thiolated oligoethylene glycol spacers increased hybridization efficiency at low hairpin probe coverages (∼(3−4) × 1011 probes/cm2), but not at higher probe coverages (1 × 1012/cm2). We also evaluated the effect of target length by adding up to 50 nonhybridizing nucleotides to the 3′ or 5′ end of the complementary target sequence. Additional nucleotides on the 3′ end of the complementary target sequence (i.e., the end near the nanowire surface) had a much greater impact on hybridization efficiency as compared to nucleotides added to the 5′ end. This work provides guidance in designing sensors in which surface-bound probes designed to adopt secondary structures are used to detect target sequences from solution. PMID:21038880
Ion-driven instabilities of surface dust ion-acoustic waves in bounded plasma devices
Lee, Myoung-Jae; Jung, Young-Dae
2018-02-01
The growth rates of the dust ion-acoustic surface wave in the plasma slab device containing ion streaming passing through the stationary electrons and dusty grains at the speed of wave phase velocity are derived and numerically analyzed. We have found that the growth rates for the resonant symmetric and antisymmetric waves are similar to the case of semi-bounded plasma when we have a thick slab. However, in the case of the symmetric wave, the growth rate moves towards the bulk wave as the slab thickness reduces. In the case of the antisymmetric wave, the growth rate increases fast as the slab thickness decreases. The growth rates of surface waves in a plasma slab are compared with those of semi-bounded and bulk waves.
Energy Technology Data Exchange (ETDEWEB)
Lee, Myoung-Jae [Department of Physics, Hanyang University, Seoul 04763 (Korea, Republic of); Research Institute for Natural Sciences, Hanyang University, Seoul 04763 (Korea, Republic of); Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr [Department of Applied Physics and Department of Bionanotechnology, Hanyang University, Ansan, Kyunggi-Do 15588 (Korea, Republic of); Department of Electrical and Computer Engineering, MC 0407, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0407 (United States)
2017-02-12
High frequency electrostatic wave propagation in a dense and semi-bounded electron quantum plasma is investigated with consideration of the Bohm potential. The dispersion relation for the surface mode of quantum plasma is derived and numerically analyzed. We found that the quantum effect enhances the frequency of the wave especially in the high wave number regime. However, the frequency of surface wave is found to be always lower than that of the bulk wave for the same quantum wave number. The group velocity of the surface wave for various quantum wave number is also obtained. - Highlights: • High frequency electrostatic wave propagation is investigated in a dense semi-bounded quantum plasma. • The dispersion relation for the surface mode of quantum plasma is derived and numerically analyzed. • The quantum effect enhances the frequency of the wave especially in the high wave number regime. • The frequency of surface wave is found to be always lower than that of the bulk wave. • The group velocity of the surface wave for various quantum wave number is also obtained.
Mechanical splitting of microtubules into protofilament bundles by surface-bound kinesin-1.
VanDelinder, Virginia; Adams, Peter G; Bachand, George D
2016-12-21
The fundamental biophysics of gliding microtubule (MT) motility by surface-tethered kinesin-1 motor proteins has been widely studied, as well as applied to capture and transport analytes in bioanalytical microdevices. In these systems, phenomena such as molecular wear and fracture into shorter MTs have been reported due the mechanical forces applied on the MT during transport. In the present work, we show that MTs can be split longitudinally into protofilament bundles (PFBs) by the work performed by surface-bound kinesin motors. We examine the properties of these PFBs using several techniques (e.g., fluorescence microscopy, SEM, AFM), and show that the PFBs continue to be mobile on the surface and display very high curvature compared to MT. Further, higher surface density of kinesin motors and shorter kinesin-surface tethers promote PFB formation, whereas modifying MT with GMPCPP or higher paclitaxel concentrations did not affect PFB formation.
Interference effects in laser-induced plasma emission from surface-bound metal micro-particles.
Feigenbaum, Eyal; Malik, Omer; Rubenchik, Alexander M; Matthews, Manyalibo J
2017-05-01
The light-matter interaction of an optical beam and metal micro-particulates at the vicinity of an optical substrate surface is critical to the many fields of applied optics. Examples of impacted fields are laser-induced damage in high power laser systems, sub-wavelength laser machining of transmissive materials, and laser-target interaction in directed energy applications. We present a full-wave-based model that predicts the laser-induced plasma pressure exerted on a substrate surface as a result of light absorption in surface-bound micron-scale metal particles. The model predictions agree with experimental observation of laser-induced shallow pits, formed by plasma emission and etching from surface-bound metal micro-particulates. It provides an explanation for the prototypical side lobes observed along the pit profile, as well as for the dependence of the pit shape on the incident laser and particle parameters. Furthermore, the model highlights the significance of the interference of the incident light in the open cavity geometry formed between the micro-particle and the substrate in the resulting pit shape.
White, P C; Munro, C H; Smith, W E
1996-06-01
An in situ surface enhanced resonance Raman scattering (SERRS) procedure is described for the analysis of a reactive dye covalently bound to a single strand of a cotton fibre. This procedure can be completed in 5 h, whereas an alternative enzyme digestion method takes approximately 21 h. These two fibre preparation methods give similar spectra from picogram quantities of dye present on a 2-5 mm length of fibre. The in situ nature of the analysis and the small sample size make this method particularly suitable for forensic applications.
The role of casein in supporting the operation of surface bound kinesin
Directory of Open Access Journals (Sweden)
Hancock William O
2008-10-01
Full Text Available Abstract Microtubules and associated motor proteins such as kinesin are envisioned for applications such as bioseparation and molecular sorting to powering hybrid synthetic mechanical devices. One of the challenges in realizing such systems is retaining motor functionality on device surfaces. Kinesin motors adsorbed onto glass surfaces lose their functionality or ability to interact with microtubules if not adsorbed with other supporting proteins. Casein, a milk protein, is commonly used in microtubule motility assays to preserve kinesin functionality. However, the mechanism responsible for this preservation of motor function is unknown. To study casein and kinesin interaction, a series of microtubule motility assays were performed where whole milk casein, or its αs1 and αs2, β or κ subunits, were introduced or omitted at various steps of the motility assay. In addition, a series of epifluorescence and total internal reflection microscopy (TIRF experiments were conducted where fluorescently labeled casein was introduced at various steps of the motility assay to assess casein-casein and casein-glass binding dynamics. From these experiments it is concluded that casein forms a bi-layer which supports the operation of kinesin. The first tightly bound layer of casein mainly performs the function of anchoring the kinesin while the second more loosely bound layer of casein positions the head domain of the kinesin to more optimally interact with microtubules. Studies on individual casein subunits indicate that β casein was most effective in supporting kinesin functionality while κ casein was found to be least effective.
Proton surface charge determination in Spodosol horizons with organically bound aluminum
Skyllberg, Ulf; Borggaard, Ole K.
1998-05-01
Net proton surface charge densities were determined in O, E, Bh, and Bs horizons of a sandy till, Spodosol from Denmark, by means of acid-base titration combined with ion adsorption in 0.005 M Ca(NO 3) 2 and independent permanent charge determination. The release of organic anions exceeded the adsorption of NO 3-, resulting in a desorption of anions in all horizons. Data were found to obey the law of balance between surface charges and adsorbed ions only when charges pertaining to Al and organic anions released during the titration experiments were accounted for, in addition to charges pertaining the potential determining ions (PDI) H + and OH - and the index ions Ca 2+ and NO 3-. It was furthermore shown that the point of zero net proton charge (PZNPC) in soils highly depends on the concentration of organically bound Al. Approaches previously used in soils, in which adsorbed Al n+ has been ignored (i.e., considered equivalent to nH + as a PDI), resulted in a PZNPC of 4.1 in the Bs horizon. If instead organically bound Al was accounted for as a counter-ion similar to 3/2Ca 2+, a PZNPC of 2.9 was obtained for the same Bs horizon. Based on PZNPC values estimated by the latter approach, combined with a weak-acid analog, it was shown that organic proton surface charges buffered pH with a similar intensity in the O, E, Bh, and Bs horizons of this study. Because the acidity of Al adsorbed to conjugate bases of soil organic acids is substantially weaker than the acidity of the corresponding protonated form of the organic acids, the point of zero net proton charge (PZNPC) will increase if the concentration of organically adsorbed Al increases at the expense of adsorbed H. This means that PZNPC values determined for soils with unknown concentrations of organically adsorbed Al are highly operational and not very meaningful as references.
Zhao, Wenqiang; Yang, Shanshan; Huang, Qiaoyun; Cai, Peng
2015-04-01
This study investigated the effect of loosely bound extracellular polymeric substances (LB-EPS) on the comprehensive surface properties of four bacteria (Bacillus subtilis, Streptococcus suis, Escherichia coli and Pseudomonas putida). The removal of LB-EPS from bacterial surfaces by high-speed centrifugation (12,000×g) was confirmed by SEM images. Viability tests showed that the percentages of viable cells ranged from 95.9% to 98.0%, and no significant difference was found after treatment (P>0.05). FTIR spectra revealed the presence of phosphodiester, carboxylic, phosphate, and amino functional groups on bacteria surfaces, and the removal of LB-EPS did not alter the types of cell surface functional groups. Potentiometric titration results suggested the total site concentrations on the intact bacteria were higher than those on LB-EPS free bacteria. Most of the acidity constants (pKa) were almost identical, except the increased pKa values of phosphodiester groups on LB-EPS free S. suis and E. coli surfaces. The electrophoretic mobilities and hydrodynamic diameters of the intact and LB-EPS free bacteria were statistically unchanged (P>0.05), indicating LB-EPS had no influence on the net surface charges and size distribution of bacteria. However, LB-ESP could enhance cell aggregation processes. The four LB-EPS free bacteria all exhibited fewer hydrophobicity values (26.1-65.0%) as compared to the intact cells (47.4-69.3%), suggesting the removal of uncharged nonpolar compounds (e.g., carbohydrates) in LB-EPS. These findings improve our understanding of the changes in cell surface characterizations induced by LB-EPS, and have important implications for assessing the role of LB-EPS in bacterial adhesion and transport behaviors. Copyright © 2015 Elsevier B.V. All rights reserved.
Harnessing surface-bound enzymatic reactions to organize microcapsules in solution.
Shklyaev, Oleg E; Shum, Henry; Sen, Ayusman; Balazs, Anna C
2016-03-01
By developing new computational models, we examine how enzymatic reactions on an underlying surface can be harnessed to direct the motion and organization of reagent-laden microcapsules in a fluid-filled microchannel. In the presence of appropriate reagents, surface-bound enzymes can act as pumps, which drive large-scale fluid flows. When the reagents diffuse through the capsules' porous shells, they can react with enzymatic sites on the bottom surface. The ensuing reaction generates fluid density variations, which result in fluid flows. These flows carry the suspended microcapsules and drive them to aggregate into "colonies" on and near the enzyme-covered sites. This aggregation continues until the reagent has been depleted and the convection stops. We show that the shape of the assembled colonies can be tailored by patterning the distribution of enzymes on the surface. This fundamental physicochemical mechanism could have played a role in the self-organization of early biological cells (protocells) and can be used to regulate the autonomous motion and targeted delivery of microcarriers in microfluidic devices.
Critical surface roughness for wall bounded flow of viscous fluids in an electric submersible pump
Deshmukh, Dhairyasheel; Siddique, Md Hamid; Kenyery, Frank; Samad, Abdus
2017-11-01
Surface roughness plays a vital role in the performance of an electric submersible pump (ESP). A 3-D numerical analysis has been carried out to find the roughness effect on ESP. The performance of pump for steady wall bounded turbulent flows is evaluated at different roughness values and compared with smooth surface considering a non-dimensional roughness factor K. The k- ω SST turbulence model with fine mesh at near wall region captures the rough wall effects accurately. Computational results are validated with experimental results of water (1 cP), at a design speed (3000 RPM). Maximum head is observed for a hydraulically smooth surface (K=0). When roughness factor is increased, the head decreases till critical roughness factor (K=0.1) due to frictional loss. Further increase in roughness factor (K>0.1) increases the head due to near wall turbulence. The performance of ESP is analyzed for turbulent kinetic energy and eddy viscosity at different roughness values. The wall disturbance over the rough surface affects the pressure distribution and velocity field. The roughness effect is predominant for high viscosity oil (43cP) as compared to water. Moreover, the study at off-design conditions showed that Reynolds number influences the overall roughness effect.
Lutz, Eric A; Sharma, Smita; Casto, Bruce; Needham, Glen; Buckley, Timothy J
2010-12-15
Carpets are both sinks and sources for exposure to chemicals, allergens, and microbes and consequently influence health, including asthma, allergies, and infectious diseases. Asthmatics, children, and the immune-compromised are particularly vulnerable to health risks resulting from exposure to carpet contaminants. To address this risk, a commercial upright vacuum cleaner with an ultraviolet germicidal lamp (λ=253.7 nm, UVC) has been developed for residential and commercial uses. However, its effectiveness in reducing microbial load on real-world carpets has not been previously demonstrated. Accordingly, the purpose of the current study was to evaluate the effectiveness of a UVC-equipped vacuum in reducing the carpet surface-bound microbial load. This was accomplished by comparing the carpet microbial surface load from pre- to post-treatment of 9 ft(2) in-use carpet sections under three treatment scenarios: 1) UVC alone (UV), 2) the beater-bar plus vacuum (BB+Vac), or 3) a combination of all three (COMB). Each treatment was two minutes in duration. Microbial surface loads were measured by pressing contact plates containing Sabourauds Dextrose agar onto the carpet surface. In-use carpets from three locations were tested in place. The treatment effect was evaluated at two levels. First, we considered the mean reduction in CFU from pre- to post-treatment for each 9 ft(2) carpet grid (n = 4 for each treatment). The second level considered each 1 ft(2) section using a paired analysis (n = 40 to 49 for each treatment). A total of 125 pre/post-sample pairs were collected across the three treatments. Results showed that all three treatments were associated with a reduction in carpet microbial load (p < 0.0001). The COMB yielded the largest reduction of 13 CFU/plate (87% reduction) and was approximately the sum of the individual effects of either UVC (6.6 CFU/plate, 60% reduction, p = 0.009) or BB+Vac (7.3 CFU/plate, 78% reduction, p < 0.0001). We therefore conclude that a
Label-free quantitative proteome analysis of the surface-bound salivary pellicle.
Delius, Judith; Trautmann, Simone; Médard, Guillaume; Kuster, Bernhard; Hannig, Matthias; Hofmann, Thomas
2017-04-01
The salivary pellicle, covering natural as well as restored tooth surfaces in the oral cavity as an immobilized protein-rich layer, acts as an important physico-chemical and biological mediator at the tooth-saliva-interface. For the first time, the pellicle's proteome of individual volunteers were analyzed separately on three consecutive days and the relative protein abundance determined by a label-free quantitative nano-LC-MS/MS approach. A total of 72 major proteins were identified in the initial pellicles formed intraorally on dental ceramic specimens already after 3min with high inter-individual and inter-day consistency. In comparison, significant differences in protein abundance were evident between subjects, thus indicating unique individual pellicle profiles. Furthermore, the relative protein abundance in pellicles was compared to the proteome pattern in the corresponding saliva samples of the same individuals to provide first data on significantly enriched and depleted salivary proteins (p <0.05) within the surface-bound salivary pellicle. Our findings reveal the initial adsorption of salivary proteins at the solid-liquid interface to be a rapid, highly selective, and reproducible process leading to the immobilization of a broad range of protective proteins and enzymes on the substratum surface within a few minutes. This provides evidence that the pellicle layer might be physiologically functional even without further maturation. Copyright © 2017 Elsevier B.V. All rights reserved.
Surface Andreev Bound States and Odd-Frequency Pairing in Topological Superconductor Junctions
Tanaka, Yukio; Tamura, Shun
2018-04-01
In this review, we summarize the achievement of the physics of surface Andreev bound states (SABS) up to now. The route of this activity has started from the physics of SABS of unconventional superconductors where the pair potential has a sign change on the Fermi surface. It has been established that SABS can be regarded as a topological edge state with topological invariant defined in the bulk Hamiltonian. On the other hand, SABS accompanies odd-frequency pairing like spin-triplet s-wave or spin-singlet p-wave. In a spin-triplet superconductor junction, induced odd-frequency pairing can penetrate into a diffusive normal metal (DN) attached to the superconductor. It causes so called anomalous proximity effect where the local density of states of quasiparticle in DN has a zero energy peak. When bulk pairing symmetry is spin-triplet px-wave, the anomalous proximity effect becomes prominent and the zero bias voltage conductance is always quantized independent of the resistance in DN and interface. Finally, we show that the present anomalous proximity effect is realized in an artificial topological superconducting system, where a nanowire with spin-orbit coupling and Zeeman field is put on the conventional spin-singlet s-wave superconductor.
Surface-bound phosphatase activity in living hyphae of ectomycorrhizal fungi of Nothofagus obliqua.
Alvarez, Maricel; Godoy, Roberto; Heyser, Wolfgang; Härtel, Steffen
2004-01-01
We determined the location and the activity of surface-bound phosphomonoesterase (SBP) of five ectomycorrhizal (EM) fungi of Nothofagus oblique. EM fungal mycelium of Paxillus involutus, Austropaxillus boletinoides, Descolea antartica, Cenococcum geophilum and Pisolithus tinctorius was grown in media with varying concentrations of dissolved phosphorus. SBP activity was detected at different pH values (3-7) under each growth regimen. SBP activity was assessed using a colorimetric method based on the hydrolysis of p-nitrophenyl phosphate (pNPP) to p-nitrophenol phosphate (pNP) + P. A new technique involving confocal laser-scanning microscopy (LSM) was used to locate and quantify SBP activity on the hyphal surface. EM fungi showed two fundamentally different patterns of SBP activity in relation to varying environmental conditions (P-concentrations and pH). In the cases of D. antartica, A. boletinoides and C. geophilum, changes in SBP activity were induced primarily by changes in the number of SBP-active centers on the hyphae. In the cases of P. tinctorius and P. involutus, the number of SBP-active centers per μm hyphal length changed much less than the intensity of the SBP-active centers on the hyphae. Our findings not only contribute to the discussion about the role of SBP-active centers in EM fungi but also introduce LSM as a valuable method for studying EM fungi.
International Nuclear Information System (INIS)
Tyshetskiy, Yu.; Kompaneets, R.; Vladimirov, S. V.
2012-01-01
Surface plasmon polaritons (SPPs) in a semi-bounded degenerate plasma (e.g., a metal) are studied using the quasiclassical mean-field kinetic model, taking into account the spatial dispersion of the plasma (due to quantum degeneracy of electrons) and electron-ion (electron-lattice, for metals) collisions. SPP dispersion and damping are obtained in both retarded (ω/k z ∼c) and non-retarded (ω/k z ≪c) regions, as well as in between. It is shown that the plasma spatial dispersion significantly affects the properties of SPPs, especially at short wavelengths (less than the collisionless skin depth, λ ≲ c/ω pe ). Namely, the collisionless (Landau) damping of SPPs (due to spatial dispersion) is comparable to the purely collisional (Ohmic) damping (due to electron-lattice collisions) in a wide range of SPP wavelengths, e.g., from λ∼20 nm to λ∼0.8 nm for SPP in gold at T = 293 K and from λ∼400 nm to λ∼0.7 nm for SPPs in gold at T = 100 K. The spatial dispersion is also shown to affect, in a qualitative way, the dispersion of SPPs at short wavelengths λ ≲ c/ω pe .
Concepcion, Javier J; Binstead, Robert A; Alibabaei, Leila; Meyer, Thomas J
2013-10-07
We report here the application of a simple hydrodynamic technique, linear sweep voltammetry with a modified rotating-ring-disc electrode, for the study of water oxidation catalysis. With this technique, we have been able to reliably obtain turnover frequencies, overpotentials, Faradaic conversion efficiencies, and mechanistic information from single samples of surface-bound metal complex catalysts.
Krimmer, Stefan G; Cramer, Jonathan; Betz, Michael; Fridh, Veronica; Karlsson, Robert; Heine, Andreas; Klebe, Gerhard
2016-12-08
A previously studied congeneric series of thermolysin inhibitors addressing the solvent-accessible S 2 ' pocket with different hydrophobic substituents showed modulations of the surface water layers coating the protein-bound inhibitors. Increasing stabilization of water molecules resulted in an enthalpically more favorable binding signature, overall enhancing affinity. Based on this observation, we optimized the series by designing tailored P 2 ' substituents to improve and further stabilize the surface water network. MD simulations were applied to predict the putative water pattern around the bound ligands. Subsequently, the inhibitors were synthesized and characterized by high-resolution crystallography, microcalorimetry, and surface plasmon resonance. One of the designed inhibitors established the most pronounced water network of all inhibitors tested so far, composed of several fused water polygons, and showed 50-fold affinity enhancement with respect to the original methylated parent ligand. Notably, the inhibitor forming the most perfect water network also showed significantly prolonged residence time compared to the other tested inhibitors.
Trans and surface membrane bound zervamicin IIB: 13C-MAOSS-NMR at high spinning speed
International Nuclear Information System (INIS)
Raap, J.; Hollander, J.; Ovchinnikova, T. V.; Swischeva, N. V.; Skladnev, D.; Kiihne, S.
2006-01-01
Interactions between 15 N-labelled peptides or proteins and lipids can be investigated using membranes aligned on a thin polymer film, which is rolled into a cylinder and inserted into the MAS-NMR rotor. This can be spun at high speed, which is often useful at high field strengths. Unfortunately, substrate films like commercially available polycarbonate or PEEK produce severe overlap with peptide and protein signals in 13 C-MAOSS NMR spectra. We show that a simple house hold foil support allows clear observation of the carbonyl, aromatic and C α signals of peptides and proteins as well as the ester carbonyl and choline signals of phosphocholine lipids. The utility of the new substrate is validated in applications to the membrane active peptide zervamicin IIB. The stability and macroscopic ordering of thin PC10 bilayers was compared with that of thicker POPC bilayers, both supported on the household foil. Sidebands in the 31 P-spectra showed a high degree of alignment of both the supported POPC and PC10 lipid molecules. Compared with POPC, the PC10 lipids are slightly more disordered, most likely due to the increased mobilities of the shorter lipid molecules. This mobility prevents PC10 from forming stable vesicles for MAS studies. The 13 C-peptide peaks were selectively detected in a 13 C-detected 1 H-spin diffusion experiment. Qualitative analysis of build-up curves obtained for different mixing times allowed the transmembrane peptide in PC10 to be distinguished from the surface bound topology in POPC. The 13 C-MAOSS results thus independently confirms previous findings from 15 N spectroscopy [Bechinger, B., Skladnev, D.A., Ogrel, A., Li, X., Rogozhkina, E.V., Ovchinnikova, T.V., O'Neil, J.D.J. and Raap, J. (2001) Biochemistry, 40, 9428-9437]. In summary, application of house hold foil opens the possibility of measuring high resolution 13 C-NMR spectra of peptides and proteins in well ordered membranes, which are required to determine the secondary and
Chiao, T.; Nijssen, B.; Stickel, L.; Lettenmaier, D. P.
2013-12-01
Hydrologic modeling is often used to assess the potential impacts of climate change on water availability and quality. A common approach in these studies is to calibrate the selected model(s) to reproduce historic stream flows prior to the application of future climate projections. This approach relies on the implicit assumptions that the sensitivities of these models to meteorological fluctuations will remain relatively constant under climate change and that these sensitivities are similar among models if all models are calibrated to the same historic record. However, even if the models are able to capture the historic variability in hydrological variables, differences in model structure and parameter estimation contribute to the uncertainties in projected runoff, which confounds the incorporation of these results into water resource management decision-making. A better understanding of the variability in hydrologic sensitivities between different models can aid in bounding this uncertainty. In this research, we characterized the hydrologic sensitivities of three watershed-scale land surface models through a case study of the Bull Run watershed in Northern Oregon. The Distributed Hydrology Soil Vegetation Model (DHSVM), Precipitation-Runoff Modeling System (PRMS), and Variable Infiltration Capacity model (VIC) were implemented and calibrated individually to historic streamflow using a common set of long-term, gridded forcings. In addition to analyzing model performances for a historic period, we quantified the temperature sensitivity (defined as change in runoff in response to change in temperature) and precipitation elasticity (defined as change in runoff in response to change in precipitation) of these three models via perturbation of the historic climate record using synthetic experiments. By comparing how these three models respond to changes in climate forcings, this research aims to test the assumption of constant and similar hydrologic sensitivities. Our
Petukh, Marharyta; Zhang, Min; Alexov, Emil
2015-12-15
Ions are engaged in multiple biological processes in cells. By binding to the macromolecules or being mobile in the solvent, they maintain the integrity of the structure of macromolecules; participate in their enzymatic activity; or screen electrostatic interactions. While experimental methods are not always able to assign the exact location of ions, computational methods are in demand. Although the majority of computational methods are successful in predicting the position of ions buried inside macromolecules, they are less effective in deciphering positions of surface bound ions. Here, we propose the new BION algorithm (http://compbio.clemson.edu/bion_server_ph/) that predicts the location of the surface bound ions. It is more efficient and accurate compared to the previous version since it uses more advanced clustering algorithm in combination with pairing rules. In addition, the BION webserver allows specifying the pH and the salt concentration in predicting ions positions. © 2015 Wiley Periodicals, Inc.
DEFF Research Database (Denmark)
Lösche, M.; Erdelen, C.; Rump, E.
1994-01-01
The structure of monomolecular layers of the protein streptavidin, specifically bound to biotin-functionalized lipid monolayers at aqueous surfaces, has been characterized. Neutron and X-ray reflectivity measurements allowed an assessment of the organization of these self-assembled systems...... with molecular resolution. Emphasis here is placed on the hydration of the lipid head groups in the bound state. For three functionalized lipids with spacers of different lengths between the biotin and their chains it was observed that the head groups were dehydrated in monolayers of the pure lipids, which were...... kept at low surface pressure before protein adsorption. The introduction of dipole moments at the interface by the admixture of phospholipids or the application of lateral pressure on the lipid monolayer before protein adsorption were found to impose an extension of the spacer moieties. The biotin...
Lenzi, A; Gandini, L; Claroni, F; Lombardo, F; Morrone, S; Dondero, F
1988-01-01
The authors report trials carried out in the preparation of semen for homologous artificial insemination in subjects with antisperm autoantibodies. The tests have demonstrated that swim-up is not able to select spermatozoa free of antibodies bound to the sperm surface. All the experiments of migration, dilution, antigenic competition and cryoconservation, carried out to evaluate the theoretical possibility of a better recovery of non "immunologically compromised" spermatozoa, have confirmed such negative results both with the Immunobead Test and Cytofluorimetric analysis.
International Nuclear Information System (INIS)
Rouquerol, J.
1964-11-01
This study is concerned with the bound water of several oxides (beryllia, alumina, silica-alumina) at different steps of their dehydration (heating temperatures between 150 and 1100 deg. C). The following techniques have been used simultaneously: Thermal analysis (a new method has been developed), nitrogen adsorption (study of the texture), Diborane hydrolysis (qualitative and quantitative analysis of surface water), Infra-red spectrography (in the absorption range of water), Nuclear magnetic resonance (in the resonance range of protons). Thanks to these different techniques, five kinds of bound water have been observed. Attention is called on the great influence of the thermal treatment conditions on the evolution of the products resulting from the decomposition of alumina α-trihydrate Al(OH) 3 and beryllium α-hydroxide, in the course of the dehydration. Moreover, the author emphasizes the peculiar properties of the two kinds of oxides (alumina and beryllia) prepared through a new method of treatment under low pressure and constant speed of decomposition. Such particular features concern mainly texture, bound water, and consequently, also catalytic activity. (author) [fr
Wear and roughness of the metal surface at polishing by bound abrasive
International Nuclear Information System (INIS)
Spasskij, M.R.; Lokhov, Yu.N.; Ashkerov, Yu.V.
1987-01-01
The model is proposed of the process of polishing of plastic metals by a resin polisher with the surface-saturated layer of abrasive. The model is based on the idea about a net independent effect of individual grains on the metal surface. A linear dependence of the wear rate on the applied pressure is substantiated. It is shown that a determining characteristic of metal in the process of polishing is elastic modulus rather than hardness or yield point. The dependence of a maximally attainable roughness of the metal surface on its plasticity, pressure, concentration and dimension of the abrasive is found
Low-frequency surface waves on semi-bounded magnetized quantum plasma
Energy Technology Data Exchange (ETDEWEB)
Moradi, Afshin, E-mail: a.moradi@kut.ac.ir [Department of Engineering Physics, Kermanshah University of Technology, Kermanshah (Iran, Islamic Republic of)
2016-08-15
The propagation of low-frequency electrostatic surface waves on the interface between a vacuum and an electron-ion quantum plasma is studied in the direction perpendicular to an external static magnetic field which is parallel to the interface. A new dispersion equation is derived by employing both the quantum magnetohydrodynamic and Poisson equations. It is shown that the dispersion equations for forward and backward-going surface waves are different from each other.
Surface-Bound Ligands Modulate Chemoselectivity and Activity of a Bimetallic Nanoparticle Catalyst
Vu, Khanh B.
2015-04-03
"Naked" metal nanoparticles (NPs) are thermodynamically and kinetically unstable in solution. Ligands, surfactants, or polymers, which adsorb at a particle\\'s surface, can be used to stabilize NPs; however, such a mode of stabilization is undesirable for catalytic applications because the adsorbates block the surface active sites. The catalytic activity and the stability of NPs are usually inversely correlated. Here, we describe an example of a bimetallic (PtFe) NP catalyst stabilized by carboxylate surface ligands that bind preferentially to one of the metals (Fe). NPs stabilized by fluorous ligands were found to be remarkably competent in catalyzing the hydrogenation of cinnamaldehyde; NPs stabilized by hydrocarbon ligands were significantly less active. The chain length of the fluorous ligands played a key role in determining the chemoselectivity of the FePt NP catalysts. (Chemical Presented). © 2015 American Chemical Society.
Energy Technology Data Exchange (ETDEWEB)
Wise K.S.; Kim, M.F.
1987-12-01
Surface protein antigens of Mycoplasma hyopneumoniae were identified by direct antibody-surface binding or by radioimmunoprecipitation of surface /sup 125/I-labeled proteins with a series of monoclonal antibodies (MAbs). Radioimmunoprecipitation of TX-114-phase proteins from cells labeled with (/sup 35/S) methionine, /sup 14/C-amino acids, or (/sup 3/H) palmitic acid showed that proteins p65, p50, and p44 were abundant and (with one other hydrophobic protein, p60) were selectively labeled with lipid. Alkaline hydroxylamine treatment of labeled proteins indicated linkage of lipids by amide or stable O-linked ester bonds. Proteins p65, p50, and p44 were highly immunogenic in the natural host as measured by immunoblots of TX-114-phase proteins with antisera from swine inoculated with whole organisms. These proteins were antigenically and structurally unrelated, since hyperimmune mouse antibodies to individual gel-purified proteins were monospecific and gave distinct proteolytic epitope maps. Intraspecies size variants of one surface antigen of M. hyopneumoniae were revealed by a MAb to p70 (defined in strain J, ATCC 25934), which recognized a large p73 component on strain VPP11 (ATCC 25617). In addition, MAb to internal, aqueous-phase protein p82 of strain J failed to bind an analogous antigen in strain VPP11.
International Nuclear Information System (INIS)
Wise, K.S.; Kim, M.F.
1987-01-01
Surface protein antigens of Mycoplasma hyopneumoniae were identified by direct antibody-surface binding or by radioimmunoprecipitation of surface 125 I-labeled proteins with a series of monoclonal antibodies (MAbs). Radioimmunoprecipitation of TX-114-phase proteins from cells labeled with [ 35 S] methionine, 14 C-amino acids, or [ 3 H] palmitic acid showed that proteins p65, p50, and p44 were abundant and (with one other hydrophobic protein, p60) were selectively labeled with lipid. Alkaline hydroxylamine treatment of labeled proteins indicated linkage of lipids by amide or stable O-linked ester bonds. Proteins p65, p50, and p44 were highly immunogenic in the natural host as measured by immunoblots of TX-114-phase proteins with antisera from swine inoculated with whole organisms. These proteins were antigenically and structurally unrelated, since hyperimmune mouse antibodies to individual gel-purified proteins were monospecific and gave distinct proteolytic epitope maps. Intraspecies size variants of one surface antigen of M. hyopneumoniae were revealed by a MAb to p70 (defined in strain J, ATCC 25934), which recognized a large p73 component on strain VPP11 (ATCC 25617). In addition, MAb to internal, aqueous-phase protein p82 of strain J failed to bind an analogous antigen in strain VPP11
Directory of Open Access Journals (Sweden)
Xiaojun Tao
Full Text Available Nanoparticle (NP compositions such as hydrophobicity and surface charge are vital to determine the presence and amount of human serum albumin (HSA binding. The HSA binding influences drug release, biocompatibility, biodistribution, and intercellular trafficking of nanoparticles (NPs. Here, we prepared 2 kinds of nanomaterials to investigate HSA binding and evaluated drug release of HSA-bound NPs. Polysaccharides (pullulan carboxyethylated to provide ionic derivatives were then conjugated to cholesterol groups to obtain cholesterol-modified carboxyethyl pullulan (CHCP. Cholesterol-modified pullulan (CHP conjugate was synthesized with a similar degree of substitution of cholesterol moiety to CHCP. CHCP formed self-aggregated NPs in aqueous solution with a spherical structure and zeta potential of -19.9 ± 0.23 mV, in contrast to -1.21 ± 0.12 mV of CHP NPs. NPs could quench albumin fluorescence intensity with maximum emission intensity gradually decreasing up to a plateau at 9 to 12 h. Binding constants were 1.12 × 10(5 M(-1 and 0.70 × 10(5 M(-1 to CHP and CHCP, respectively, as determined by Stern-Volmer analysis. The complexation between HSA and NPs was a gradual process driven by hydrophobic force and inhibited by NP surface charge and shell-core structure. HSA conformation was altered by NPs with reduction of α-helical content, depending on interaction time and particle surface charges. These NPs could represent a sustained release carrier for mitoxantrone in vitro, and the bound HSA assisted in enhancing sustained drug release.
Surface-Bound Molecular Film Structure Effects on Electronic and Magnetic Properties
Pronschinske, Alex M.
This thesis dissertation will discuss the importance of understanding the driving forces of molecular assembly on surfaces and the need to characterize the electronic and magnetic properties of the resulting organic films. Furthermore, experimental results on model organic molecular assemblies, benzoate on Cu(110) and Fe[(H2BPz2)2bpy] ("Fe-bpy") on Au(111), and their novel film properties will be presented. The primary experimental techniques used in this work are scanning tunneling microscopy and spectroscopy (STM, STS), and so a theoretical characterization of constant current distance-voltage STS (z(V)-STS) will also be developed. Deposition of benzoic acid (C6H5COOH) on to Cu(110) will be used to create a diverse molecular environment of benzoate molecules (C6H5COO+). In this film we will utilize structural phases consisting of co-existing orientation (alpha-phase) and uniform molecular orientation (c(8x2) phase) to probe electric potential variation across the surface of the film. Using z( V)-STS find that the electron affinity level of a molecule's near-neighbor will exert a substrate-mediated influence on the energy of the molecule's image potential state; which we describe using a 1-D dielectric continuum model. Motivated by the unique utility of z(V)-STS for gentle probing of molecular electronic structure and electric potential we perform a thorough theoretical characterize of z( V)-STS. We derive a differential equation for simulating z(V)-STS spectra under the standard approximation of a square tunneling barrier. Moreover, we derive an equation for sample density of states (DOS) that is applicable for all modes of STS. The central result of this work for interpretation of z(V)-STS results is a characterization of systematic error between state energy and z(V)-STS peak location, as well we show that empirical normalization procedure for removing background distortion from constant height current-voltage STS, (V/I)dI/dV, is also applicable to z(V)-STS is
On-Demand Final State Control of a Surface-Bound Bistable Single Molecule Switch.
Garrido Torres, José A; Simpson, Grant J; Adams, Christopher J; Früchtl, Herbert A; Schaub, Renald
2018-04-12
Modern electronic devices perform their defined action because of the complete reliability of their individual active components (transistors, switches, diodes, and so forth). For instance, to encode basic computer units (bits) an electrical switch can be used. The reliability of the switch ensures that the desired outcome (the component's final state, 0 or 1) can be selected with certainty. No practical data storage device would otherwise exist. This reliability criterion will necessarily need to hold true for future molecular electronics to have the opportunity to emerge as a viable miniaturization alternative to our current silicon-based technology. Molecular electronics target the use of single-molecules to perform the actions of individual electronic components. On-demand final state control over a bistable unimolecular component has therefore been one of the main challenges in the past decade (1-5) but has yet to be achieved. In this Letter, we demonstrate how control of the final state of a surface-supported bistable single molecule switch can be realized. On the basis of the observations and deductions presented here, we further suggest an alternative strategy to achieve final state control in unimolecular bistable switches.
Coleman, B K; Wells, J R; Nazaroff, W W
2010-02-01
The reaction of ozone with permethrin can potentially form phosgene. Published evidence on ozone levels and permethrin surface concentrations in aircraft cabins indicated that significant phosgene formation might occur in this setting. A derivatization technique was developed to detect phosgene with a lower limit of detection of 2 ppb. Chamber experiments were conducted with permethrin-coated materials (glass, carpet, seat fabric, and plastic) exposed to ozone under cabin-relevant conditions (150 ppb O(3), 4.5/h air exchange rate, means of material-balance modeling indicates that the upper limit on the phosgene level in aircraft cabins resulting from this chemistry is approximately 1 microg/m(3) or approximately 0.3 ppb. It was thus determined that phosgene formation, if it occurs in aircraft cabins, is not likely to exceed relevant, health-based phosgene exposure guidelines. Phosgene formation from ozone-initiated oxidation of permethrin in the aircraft cabin environment, if it occurs, is estimated to generate levels below the California Office of Environmental Health Hazard Assessment acute reference exposure level of 4 microg/m(3) or approximately 1 ppb.
Laser-based standoff detection of surface-bound explosive chemicals
Huestis, David L.; Smith, Gregory P.; Oser, Harald
2010-04-01
Avoiding or minimizing potential damage from improvised explosive devices (IEDs) such as suicide, roadside, or vehicle bombs requires that the explosive device be detected and neutralized outside its effective blast radius. Only a few seconds may be available to both identify the device as hazardous and implement a response. As discussed in a study by the National Research Council, current technology is still far from capable of meeting these objectives. Conventional nitrocarbon explosive chemicals have very low vapor pressures, and any vapors are easily dispersed in air. Many pointdetection approaches rely on collecting trace solid residues from dust particles or surfaces. Practical approaches for standoff detection are yet to be developed. For the past 5 years, SRI International has been working toward development of a novel scheme for standoff detection of explosive chemicals that uses infrared (IR) laser evaporation of surfacebound explosive followed by ultraviolet (UV) laser photofragmentation of the explosive chemical vapor, and then UV laser-induced fluorescence (LIF) of nitric oxide. This method offers the potential of long standoff range (up to 100 m or more), high sensitivity (vaporized solid), simplicity (no spectrometer or library of reference spectra), and selectivity (only nitrocompounds).
Energy Technology Data Exchange (ETDEWEB)
Roncaratti, L. F., E-mail: lz@fis.unb.br; Leal, L. A.; Silva, G. M. de [Instituto de Física, Universidade de Brasília, 70910 Brasília (Brazil); Pirani, F. [Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, 06123 Perugia (Italy); Aquilanti, V. [Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, 06123 Perugia (Italy); Instituto de Física, Universidade Federal da Bahia, 40210 Salvador (Brazil); Gargano, R. [Instituto de Física, Universidade de Brasília, 70910 Brasília (Brazil); Departments of Chemistry and Physics, University of Florida, Quantum Theory Project, Gainesville, Florida 32611 (United States)
2014-10-07
We consider the analytical representation of the potential energy surfaces of relevance for the intermolecular dynamics of weakly bound complexes of chiral molecules. In this paper we study the H{sub 2}O{sub 2}−Ng (Ng=He, Ne, Ar, Kr, and Xe) systems providing the radial and the angular dependence of the potential energy surface on the relative position of the Ng atom. We accomplish this by introducing an analytical representation which is able to fit the ab initio energies of these complexes in a wide range of geometries. Our analysis sheds light on the role that the enantiomeric forms and the symmetry of the H{sub 2}O{sub 2} molecule play on the resulting barriers and equilibrium geometries. The proposed theoretical framework is useful to study the dynamics of the H{sub 2}O{sub 2} molecule, or other systems involving O–O and S–S bonds, interacting by non-covalent forces with atoms or molecules and to understand how the relative orientation of the O–H bonds changes along collisional events that may lead to a hydrogen bond formation or even to selectivity in chemical reactions.
Catastrophic instabilities of modified DA-DC hybrid surface waves in a semi-bounded plasma system
Energy Technology Data Exchange (ETDEWEB)
Lee, Myoung-Jae [Department of Physics and Research Institute for Natural Sciences, Hanyang University, Seoul 04763 (Korea, Republic of); Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr [Department of Applied Physics and Department of Bionanotechnology, Hanyang University, Ansan, Kyunggi-Do 15588, South Korea and Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180-3590 (United States)
2016-06-15
We find the catastrophic instabilities and derive the growth rates for the dust-cyclotron resonance (DCR) and dust-rotation resonance (DRR) modes of the modified dust-acoustic and dust-cyclotron (DA-DC) hybrid surface waves propagating at the plasma–vacuum interface where the plasma is semi-bounded and composed of electrons and rotating dust grains. The effects of magnetic field and dust rotation frequency on the DCR- and DDR-modes are also investigated. We find that the dust rotation frequency enhances the growth rate of DCR-mode and the effect of dust rotation on this resonance mode decreases with an increase of the wave number. We also find that an increase of magnetic field strength enhances the DCR growth rate, especially, for the short wavelength regime. In the case of DRR-mode, the growth rate is found to be decreased less sensitively with an increase of the wave number compared with the case of DCR, but much significantly enhanced by an increase of dust rotation frequency. The DRR growth rate also decreases with an increase of the magnetic field strength, especially in the long wavelength regime. Interestingly, we find that catastrophic instabilities occur for both DCR- and DRR-modes of the modified DA-DC hybrid surface waves when the rotational frequency is close to the dust-cyclotron frequency. Both modes can also be excited catastrophically due to the cooperative interaction between the DCR-mode and the DRR-mode.
The subglacial Lake Vostok (East Antarctica) surface snow is Earth-bound DNA (and dust)-free
Bulat, S.; Marie, D.; Bulat, E.; Alekhina, I.; Petit, J.-R.
2012-09-01
came up with only contaminant bacterial phylotypes (mostly of human source). The bioexposure trials showed that even in one day of open exposure the gDNA of rather complex microbial community composition was fatally damaged in terms of long-, mid-range and short-size amplicon generation in PCR. All this testify for very harsh conditions for life to survive the climate conditions of Central East Antarctica which could be considered as a presentday 'zone mortale' or 'polar desert' for known Earthbound microbial life forms. In addition this means that no life seeds are expected to reach subglacial lakes and water reservoirs and establish indigenous lake microbiota during their transit through the thick and aged Antarctic ice sheet upon its bottom melting. In general the subglacial Lake Vostok surface (ice sheet as well) environ represents the unique test area (sterile - in fact Earth-bound DNA-free and clean - in fact Earth-bound dust-free) for advancing extraterrestrial (ET) life detection technologies and searching for ET life indices in AMMs and IDPs.
Energy Technology Data Exchange (ETDEWEB)
Moradi, Afshin, E-mail: a.moradi@kut.ac.ir [Department of Engineering Physics, Kermanshah University of Technology, Kermanshah (Iran, Islamic Republic of)
2016-04-15
In a recent article [Niknam et al., Phys. Plasmas 20, 122106 (2013)], Niknam et al. investigated the propagation of TM surface waves on a semi-bounded quantum magnetized collisional plasma in the Faraday configuration (in this case, the magnetic field is parallel to the both of the plasma surface and direction of propagation). Here, we present a fresh look at the problem and show that TM surface waves cannot propagate on surface of the present system. We find in the Faraday configuration the surface waves acquire both TM and TE components due to the cyclotron motion of electrons. Therefore, the main result of the work by Niknam et al. is incorrect.
Energy Technology Data Exchange (ETDEWEB)
Sheridan, Matthew V.; Sherman, Benjamin D.; Marquard, Seth L.; Fang, Zhen; Ashford, Dennis L.; Wee, Kyung-Ryang; Gold, Alexander S.; Alibabaei, Leila; Rudd, Jennifer A.; Coggins, Michael K.; Meyer, Thomas J.
2015-11-12
Electrocatalytic water oxidation by the catalyst, ruthenium 2,2'-bipyridine-6,6'-dicarboxylate (bda) bis-isoquinoline (isoq), [Ru(bda)(isoq)_{2}], 1, was investigated at metal oxide electrodes surface-derivatized with electron transfer (ET) mediators. At indium-doped tin oxide (ITO) in pH 7.2 in H_{2}PO_{4}–/HPO_{4}^{2}– buffers in 0.5 M NaClO_{4} with added acetonitrile (MeCN), the catalytic activity of 1 is enhanced by the surface-bound redox mediators [Ru (4,4'-PO_{3}H_{2}-bpy)(4,4'-R-bpy)_{2}]^{2+} (RuPbpyR_{2}^{2+}, R = Br, H, Me, or OMe, bpy = 2,2'-bipyridine). Rate-limiting ET between the Ru^{3+} form of the mediator and the Ru^{IV}(O) form in the [Ru^{V/IV}(O)]^{+/0} couple of 1 is observed at relatively high concentrations of HPO_{4}^{2–} buffer base under conditions where O···O bond formation is facilitated by atom-proton transfer (APT). For the solution [Ru(bpy)_{3}]^{3+/2+} mediator couple and 1 as the catalyst, catalytic currents vary systematically with the concentration of mediator and the HPO_{4}^{2–} buffer base concentration. Electron transfer mediation of water oxidation catalysis was also investigated on nanoparticle TiO_{2} electrodes co-loaded with catalyst [Ru(bda)(py-4-O(CH_{2})_{3}-PO_{3}H_{2})_{2}], 2, (py = pyridine) and RuPbpyR_{2}^{2+} (R = H, Me, or OMe) with an interplay between rate-limiting catalyst oxidation and rate-limiting O···O bond formation by APT. Lastly, the co-loaded assembly RuPbpyR_{2}^{2+} + 2 has been investigated in a dye-sensitized photoelectrosynthesis cell for water splitting.
Gutiérrez-Rodríguez, A
2003-01-01
A bound on the nu /sup tau / magnetic moment is calculated through the reaction e/sup +/e/sup -/ to nu nu gamma at the Z/sub 1/-pole, and in the framework of a left-right symmetric model at LEP energies. We find that the bound is almost independent of the mixing angle phi of the model in the allowed experimental range for this parameter. (31 refs).
International Nuclear Information System (INIS)
Levy, N.J.; Kasper, D.L.
1986-01-01
The role of surface-bound type Ia group B Streptococcus (GBS) capsular polysaccharide in anti-body-independent binding of C1 and activation of the classic component pathway was investigated. In a radiolabeled bacterial-polymorphonuclear leukocyte (PMN) association assay, a measure of bacterial opsonization, preincubation of 3 H-type Ia GBS with purified F(ab') 2 to the organism blocked the association of the bacteria with PMN', and the inhibitory effect was dose dependent. The specificity of F(ab') 2 blocking was shown after adsorption of F(ab') 2 with type Ia polysaccharide-sensitized erythrocytes. Polysaccharide-adsorbed F(ab') 2 had a 70% decrease in ability to block the association of bacteria with PMN. Neuraminidase digestion removed 80% of the terminal sialic acid residues from the native polysaccharide. These neuraminidase-digested organisms had a 72% decrease in binding and transfer of purified C1 compared with non-enzyme-treated organisms. Type Ia capsular polysaccharide bound to sheep erythrocytes promoted classic complement pathway-mediated hemolysis of the cells. The role of C1 inhibitor (INH) in modulation of C1 activation by the organisms was investigated. The possibility existed that the C1 INH could be bound by the bacteria, allowing C1 activation to occur in the fluid phase. The inhibitor was purified from human serum, and its activity was measured before and after incubation with type Ia GBS. The organisms had no effect on C1 INH activity. Thus surface-bound capsular polysacchardie of type Ia GBS mediates C1 binding and classic pathway activation, and this does not involve the C1 INH
Grover, Phulwinder K; Thurgood, Lauren A; Wang, Tingting; Ryall, Rosemary L
2010-03-01
To compare the binding to Madin-Darby canine kidney (MDCK)-II cells of: (i) inorganic calcium oxalate monohydrate (iCOM) crystals and COM crystals precipitated from urine containing different concentrations of protein; and (ii) urinary COM crystals containing intracrystalline and intracrystalline + surface-bound protein. Urinary COM crystals were generated in sieved (sCOM), centrifuged and filtered (cfCOM), and ultrafiltered (ufCOM) portions of a pooled human urine and their adhesion to MDCK-II cells was compared using six different ultrafiltered urine samples as the binding medium. Crystal matrix extract (CME) was prepared by demineralizing calcium oxalate crystals precipitated from human urine and used to prepare COM crystals with intracrystalline, and intracrystalline + surface-bound CME at protein concentrations of 0, 0.05, 0.1, 0.5 and 5.0 mg/L. The amount of protein associated with the crystals was qualitatively assessed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blotting, using prothrombin fragment 1 (PTF1) as a marker. Protein concentration was determined in sieved, centrifuged and filtered, and ultrafiltered fractions of 10 additional urine samples. The median crystal attachment in the six urine types decreased in the order iCOM > ufCOM > cfCOM = sCOM, in inverse proportion to the concentration of protein in the solution or urine from which they were precipitated. sCOM and cfCOM crystals bound approximately 23% less than iCOM crystals. The attachment of COM crystals generated in the presence of increasing concentrations of CME proteins was unaffected up to a concentration of 5 mg/L, but binding of crystals containing the same concentrations of intracrystalline + surface-bound proteins decreased proportionally at protein concentrations from 0 to 5.0 mg/L. Inorganic COM crystals bind significantly more strongly to MDCK-II cells than urinary crystals precipitated from sieved, centrifuged and filtered, and ultrafiltered urine
Directory of Open Access Journals (Sweden)
Igor B. Krasnyuk
2009-01-01
Full Text Available The asymptotical behavior of order parameter in confined binary mixture is considered in one-dimensional geometry. The interaction between bulk and surface forces in the mixture is investigated. Its established conditions are when the bulk spinodal decomposition may be ignored and when the main role in the process of formation of the oscillating asymptotic periodic spatiotemporal structures plays the surface-directed spinodal decomposition which is modelled by nonlinear dynamical boundary conditions.
Fukunishi, Miya; Inoue, Yuuki; Morisaki, Hirobumi; Kuwata, Hirotaka; Ishihara, Kazuhiko; Baba, Kazuyoshi
The aim of this study was to examine the ability of a poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butylmethacrylate-co-2-methacryloyloxyethyloxy-p-azidobenzoate) (PMBPAz) coating on polymethyl methacrylate (PMMA)-based dental resin to inhibit bacterial plaque formation, as well as the polymer's durability against water soaking and chemical exposure. Successful application of PMBPAz on PMMA surfaces was confirmed by x-ray photoelectron spectroscopy (XPS) and measuring the static air contact angle in water. The anti-adhesive effects to bacterial plaque were evaluated using Streptococcus mutans biofilm formation assay. The mechanical and chemical durabilities of the PMBPAz coating on the PMMA surfaces were examined using soaking and immersion tests, respectively. XPS signals for phosphorus and nitrogen atoms and hydrophilic status on PMMA surfaces treated with PMBPAz were observed, indicating the presence of the polymer on the substrates. The treated PMMA surfaces showed significant inhibition of S mutans biofilm formation compared to untreated surfaces. The PMBPAz coating was preserved after water soaking and chemical exposure. In addition, water soaking did not decrease the ability of treated PMMA to inhibit biofilm formation compared to treated PMMA specimens not subjected to water soaking. This study suggests that PMBPAz coating may represent a useful modification to PMMA surfaces for inhibiting denture plaque accumulation.
London, Gabor; Carroll, Gregory T.; Feringa, Ben L.
2013-01-01
The attachment of molecular rotary motors containing triethoxysilane functional groups to quartz, silicon and mica surfaces is described. Motors containing silane coupling agents in their structure form stable molecular layers on quartz and silicon surfaces. Motors attached to these surfaces were
van der Vegte, E.W.; Hadziioannou, G
1997-01-01
In this paper we present a scanning force microscopy (SFM) study on electrostatic and hydrogen-bonding interactions between chemically modified SFM probes and surface functional groups. pH-dependent adhesion force measurements in aqueous media between various ionizable functional groups showed a
Ullien, D.; Thüne, P.C.; Jager, W.F.; Sudhölter, E.J.R.; De Smet, L.C.P.M.
2014-01-01
4-Nitrobenzenediazonium (4-NBD) and 4-bromobenzenediazonium (4-BBD) salts were grafted electrochemically onto H-terminated, p-doped silicon (Si) surfaces. Atomic force microscopy (AFM) and ellipsometry experiments clearly showed layer thicknesses of 2–7 nm, which indicate multilayer formation.
Gonçalvès, J; Rousseau-Gueutin, P
2008-04-15
A model to simulate the density of solutions adsorbed onto clay mineral surfaces is proposed. In this model, the alteration of the ionic distribution caused by the electric field associated with the surface charge of clay platelets is accounted for using an electrical triple-layer model with an overlapping diffuse layer. The combined effects of ion hydration and the electric field on the structure of water are introduced through their influence on the partial molar volume of water. This model, applied to Na-montmorillonite, simulates the distribution of the interplatelet solution density as a function of the distance to the mineral surface. High densities in the direct vicinity of the surface and slightly lower density (a few percent) than the normal density in the diffuse layer are obtained. These results show good consistency with the available data on bentonite and with the densities that can be inferred from molecular dynamics simulations. This model shows that the interplatelet distance plays an important role in the distribution of the mass density of the solution in the pore space of clay rocks.
Energy Technology Data Exchange (ETDEWEB)
Blacha-Grzechnik, Agata, E-mail: agata.blacha@polsl.pl [Faculty of Chemistry, Silesian University of Technology, Strzody 9, 44-100 Gliwice (Poland); Piwowar, Katarzyna; Krukiewicz, Katarzyna [Faculty of Chemistry, Silesian University of Technology, Strzody 9, 44-100 Gliwice (Poland); Koscielniak, Piotr; Szuber, Jacek [Institute of Electronics, Silesian University of Technology, Akademicka 16, 44-100 Gliwice (Poland); Zak, Jerzy K. [Faculty of Chemistry, Silesian University of Technology, Strzody 9, 44-100 Gliwice (Poland)
2016-05-15
Highlights: • The selected group of four NH{sub 2}-derivatives of phenothiazine was grafted to Glassy Carbon (GC) surface. • The grafted phenothiazines are able to generate {sup 1}O{sub 2} when activated by the radiation. • Such modified solid surfaces may find their application in the wastewater treatment. - Abstract: The selected group of four amine-derivatives of phenothiazine was covalently grafted to the glassy carbon surface in the four-step procedure consisting of the electrochemical reduction of the diazonium salt followed by the electrochemical and chemical post-modification steps. The proposed strategy involves the bonding of linker molecule to which the photosensitizer is attached. The synthesized organic layers were characterized by means of cyclic voltammetry, XPS and Raman Spectroscopy. It was shown that the phenothiazines immobilized via proposed strategy retain their photochemical properties and are able to generate {sup 1}O{sub 2} when activated by the laser radiation. The effectiveness of in situ singlet oxygen generation by those new solid photoactive materials was determined by means of UVVis spectroscopy. The reported, covalently modified solid surfaces may find their application as the singlet oxygen photogenerators in the fine chemicals’ synthesis or in the wastewater treatment.
Nanoparticular surface-bound PCBs, PCDDs, and PCDFs-a novel class of potentially higher toxic POPs.
Schön, Peter; Ctistis, Georgios; Bakker, Wouter; Luthe, Gregor
2017-05-01
In a previous study, Env Sci Poll Res:1-7, 2015 showed that polychlorinated biphenyls (PCBs), polychlorinated dibenzo dioxins (PCDDs), and polychlorinated dibenzo furanes (PCDFs) are found in commercially available (nano) particular titanium dioxide as a result of the fabrication. Here, we give a brief perspective and reason the toxicity of these new classes of persistent organic pollutants (POPs) by reviewing also their nanoparticular properties, such as surface-to-volume ratio, photocatalytic activity, polarity shifts, and stealth effect. These insights point towards a new class of POPs and toxicologic effects, which are related to the size but not a result of nanotechnology itself. We pave the way to the understanding of until now unresolved very complex phenomena, such as the indoor exposure, formation, and transformation of POP and sick-building syndrome. This is a fundamental message for nanotoxicology and kinetics and should be taken into account when determining the toxicity of nanomaterials and POPs separately and as a combination.
Ullien, Daniela; Thüne, Peter C; Jager, Wolter F; Sudhölter, Ernst J R; de Smet, Louis C P M
2014-09-28
4-Nitrobenzenediazonium (4-NBD) and 4-bromobenzenediazonium (4-BBD) salts were grafted electrochemically onto H-terminated, p-doped silicon (Si) surfaces. Atomic force microscopy (AFM) and ellipsometry experiments clearly showed layer thicknesses of 2-7 nm, which indicate multilayer formation. Decreasing the diazonium salt concentration and the reaction time resulted in a smaller layer thickness, but did not prevent the formation of multilayers. It was demonstrated, mainly by X-ray photoelectron spectroscopy (XPS), that the diazonium salts not only react with the H-terminated Si surface, but also with electrografted phenyl groups via azo-bond formation. These azo bonds can be electrochemically reduced at Ered = -1.5 V, leading to the corresponding amino groups. This reduction resulted in a modest decrease in layer thickness, and did not yield monolayers. This indicates that other coupling reactions, notably a biphenyl coupling, induced by electrochemically produced phenyl radicals, take place as well. In addition to the azo functionalities, the nitro functionalities in electrografted layers of 4-NBD were independently reduced to amino functionalities at a lower potential (Ered = -2.1 V). The presence of amino functionalities on fully reduced layers, both from 4-NBD- and 4-BBD-modified Si, was shown by the presence of fluorine after reaction with trifluoroacetic anhydride (TFAA). This study shows that the electrochemical reduction of azo bonds generates amino functionalities on layers produced by electrografting of aryldiazonium derivatives. In this way multifunctional layers can be formed by employing functional aryldiazonium salts, which is believed to be very practical in the fabrication of sensor platforms, including those made of multi-array silicon nanowires.
Shafieyan, Yousef; Tiedemann, Kerstin; Goulet, Andrew; Komarova, Svetlana; Quinn, Thomas M
2012-06-01
Osteoclast differentiation is affected by substrate characteristics and environmental conditions; these parameters are therefore of interest for understanding bone remodeling. As a step toward osteoclast mechanotransduction experiments, we aimed to optimize conditions for osteoclast differentiation on extendable poly(dimethylsiloxane) (PDMS) substrates. Because cells attach poorly on PDMS alone, chemical modification by covalent attachment of collagen type I was performed. Effects of collagen surface concentrations on monocyte fusion and osteoclast differentiation were examined. Osteoclasts differentiated on modified PDMS were fewer in number (by ∼50%) than controls on polystyrene physically modified by nonspecific attachment of collagen, and exhibited somewhat different morphologies. Nevertheless, for certain choices of the chemical modification procedures, appropriate differentiation on PDMS was still evident by qRT-PCR analysis for tartrate-resistant acid phosphate (TRAP) and cathepsin K (CTSK) gene expression, positive TRAP staining, fluorescent phalloidin staining showing actin ring formation and bone resorption assays. At relatively high collagen surface densities, monocyte clumps appeared on PDMS suggesting substrate-induced alterations to monocyte fusion. Covalently bound collagen can therefore be used to promote osteoclast differentiation on extendable PDMS substrates. Under appropriate conditions osteoclasts retain similar functionality as on polystyrene, which will enable future studies of osteoclast interactions with microstructured surfaces and mechanostimulation. Copyright © 2012 Wiley Periodicals, Inc.
Auteri, Francesco Paul
Electron paramagnetic resonance (EPR) spectroscopy is sensitive to molecular rotational correlation times in the range of 10^{-6} to 10^{-11} seconds. EPR spin labels are often attached or incorporated into molecular structures as probes of local viscosities and dynamics. In part I of this work, methods of covalently attaching a variety of spin labels to silica and alumina ceramic surfaces are developed in an attempt to study local viscosities at varying distances from about 5 A^circ to 25 A^circ from the ceramic/liquid interface. Three solvents, diethyl ether, benzene, and cyclohexane, are chosen for detailed study in combination with the spin labels, TEMPOL, 5-DOXYL, and 12-DOXYL. EPR spectra of each system are taken over the range of temperatures from -140 ^circC to 50^circ C (or just below the solvent boiling point). Spectra show good sensitivity to solvent, temperature, and probe. The effect of adding 3% (w/o) poly-(octadecyl-methacrylate) (PODM) to benzene and cyclohexane on spin label mobility is also studied in this work. Rotational correlation times from lineshapes are analyzed assuming isotropic rotation using spectral splitting, line width, and simulation methods. These approaches are often inadequate for the more complex spectral line shapes observed for tethered spin labels, especially in the intermediate motional regime where sensitivity to anisotropic dynamics is greatest. In part II of this work, a novel approach to the prediction of spectral line shapes is developed. It is shown that EPR spectra may be computed directly from molecular trajectories using classical approximations to describe the time evolution of the magnetization vector under fluctuating effective interaction tensor values. Line shape simulations using molecular trajectories generated by Brownian dynamics theory are less time intensive than existing methods. Simulation of magnetic resonance line shapes by molecular trajectories as generated by programs such as CHARMM promises to be
Human Noroviruses (HuNoVs) are the main cause of nonbacterial gastroenteritis. Contaminated produce is a main vehicle for dissemination of HuNoVs. In this study, we used an ice nucleation protein (INP) mediated surface display system to present the protruding domain of GII.4 HuNoV capsid protein (G...
Czech Academy of Sciences Publication Activity Database
Dyr, J. E.; Tichý, Ivo; Jiroušková, M.; Tobiška, Petr; Slavík, Radan; Homola, Jiří; Suttnar, J.
1998-01-01
Roč. 9, č. 7 (1998), s. 675 ISSN 0957-5235 R&D Projects: GA ČR GA303/96/1358 Institutional research plan: CEZ:AV0Z2067918 Keywords : surface plasmons * biosensors * biomedical engineering Subject RIV: CE - Biochemistry
Gross, Catharina; Koelch, Walter; DeMaio, Antonio; Arispe, Nelson; Multhoff, Gabriele
2003-10-17
Cell surface-bound heat shock protein 70 (Hsp70) renders tumor cells more sensitive to the cytolytic attack mediated by natural killer (NK) cells. A 14-amino acid Hsp70 sequence, termed TKD (TKDNNLLGRFELSG, aa450-463) could be identified as the extracellular localized recognition site for NK cells. Here, we show by affinity chromatography that both, full-length Hsp70-protein and Hsp70-peptide TKD, specifically bind a 32-kDa protein derived from NK cell lysates. The serine protease granzyme B was uncovered as the 32-kDa Hsp70-interacting protein using matrix-assisted laser desorption ionization time-of-flight mass peptide fingerprinting. Incubation of tumor cells with increasing concentrations of perforin-free, isolated granzyme B shows specific binding and uptake in a dose-dependent manner and results in initiation of apoptosis selectively in tumor cells presenting Hsp70 on the cell surface. Remarkably, Hsp70 cation channel activity was also determined selectively in purified phospholipid membranes of Hsp70 membrane-positive but not in membrane-negative tumor cells. The physiological role of our findings was demonstrated in primary NK cells showing elevated cytoplasmic granzyme B levels following contact with TKD. Furthermore, an increased lytic activity of Hsp70 membrane-positive tumor cells could be associated with granzyme B release by NK cells. Taken together we propose a novel perforin-independent, granzyme B-mediated apoptosis pathway for Hsp70 membrane-positive tumor cells.
Vanshylla, Kanika; Opazo, Felipe; Gronke, Konrad; Wienands, Jürgen; Engels, Niklas
2018-03-01
Immunoglobulin E (IgE) antibodies are key mediators of allergic reactions. Due to their potentially harmful anaphylactic properties, their production is tightly regulated. The membrane-bound isoform of IgE (mIgE), which is an integral component of the B cell antigen receptor, has been shown to be critical for the regulation of IgE responses in mice. In primate species including humans, mIgE can be expressed in two isoforms that are produced by alternative splicing of the primary ε Ig heavy chain transcript, and differ in the absence or presence of an extracellular membrane-proximal domain (EMPD) consisting of 52 amino acids. However, the function of the EMPD remains unclear. Here, we demonstrate that the EMPD restricts surface expression of mIgE-containing BCRs in human and murine B cells. The EMPD does not interfere with BCR assembly but acts as an autonomous endoplasmic reticulum retention domain. Limited surface expression of EMPD-containing mIgE-BCRs caused impaired activation of intracellular signaling cascades and hence represents a regulatory mechanism that may control the production of potentially anaphylactic IgE antibodies in primate species. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Directory of Open Access Journals (Sweden)
Christina Koers-Wunrau
Full Text Available BACKGROUND: The matrix metalloproteinases (MMPs and their endogenous regulators, the tissue inhibitor of metalloproteinases (TIMPs 1-4 are responsible for the physiological remodeling of the extracellular matrix (ECM. Among all TIMPs, TIMP3 appears to play a unique role since TIMP3 is a secreted protein and, unlike the other TIMP family members, is tightly bound to the ECM. Moreover TIMP3 has been shown to be able to induce apoptotic cell death. As little is known about the underlying mechanisms, we set out to investigate the pro-apoptotic effect of TIMP3 in human mesenchymal cells. METHODOLOGY/PRINCIPAL FINDINGS: Lentiviral overexpression of TIMP3 in mesenchymal cells led to a strong dose-dependent induction of ligand-independent apoptosis as reflected by a five-fold increase in caspase 3 and 7 activity compared to control (pLenti6/V5-GW/lacZ or uninfected cells, whereas exogenous TIMP3 failed to induce apoptosis. Concordantly, increased cleavage of death substrate PARP and the caspases 3 and 7 was observed in TIMP3 overexpressing cultures. Notably, activation of caspase-8 but not caspase-9 was observed in TIMP3-overexpressing cells, indicating a death receptor-dependent mechanism. Moreover, overexpression of TIMP3 led to a further induction of apoptosis after stimulation with TNF-alpha, FasL and TRAIL. Most interestingly, TIMP3-overexpression was associated with a decrease in phosphorylation of cRaf, extracellular signal-regulated protein kinase (Erk1/2, ribosomal S6 kinase (RSK1 and Akt and serum deprivation of TIMP3-overexpressing cells resulted in a distinct enhancement of apoptosis, pointing to an impaired signaling of serum-derived survival factors. Finally, heparinase treatment of heparan sulfate proteoglycans led to the release of TIMP3 from the surface of overexpressing cells and to a significant decrease in apoptosis indicating that the binding of TIMP3 is necessary for apoptosis induction. CONCLUSION: The results demonstrate that
Bennett, C.; Poston, M.; McLain, J. L.; Orlando, T. M.
2014-12-01
The generation of surface-bound exospheres present around the Moon, Mercury and other airless rocky bodies are produced primarily by the interaction of micrometeoroid impacts and charged particles from the solar wind, and magnetospheres with those surfaces. While the study of the interactions of both micrometeoroids and ion sputtering are well investigated, the contributions arising from energetic electron interactions are typically less-well established. Observations from the Fast Imaging Plasma Spectrometer (FIPS), taken < 400 km from the surface, have shown a plasma cusp with energetic heavy ions (i.e. Na+- and O+-groups) for which the source has not been determined. However, the precipitation of keV electrons onto the surfaces of Mercury has recently been inferred from measurements using the X-Ray Spectrometer (XRS) instrument onboard the MESSENGER spacecraft observations of the night-side of Mercury. A newly developed global kinetic transport model suggests that electron-stimulated desorption (ESD), and possibly light ion stimulated desorption (ISD), can directly yield ions that can be transported and dynamically accelerated to the plasma cusp regions observed by FIPS. In addition, keV electrons and ions from the solar wind and Earth's magnetosphere frequently bombard with the lunar surface. Here, we present some of the most recent results from our ongoing work studying the effects of photon-stimulated desorption (PSD), ion-stimulated desorption (ISD) and implantation, as well as electron-stimulated desorption (ESD). Apollo samples collected from both the lunar highland and Mare regions, as well as simulants of the Mercury Regolith have been investigated. The temperature- (100-600 K) and energy-dependence (threshold - 2 keV) of ESD time-of-flight (ToF) results will be presented for these materials along with some preliminary results from our group based on photon-desorption studies of water on lunar material, temperature-programmed desorption (TPD) studies of
Mele, Valentina; Muraro, Manuele G; Calabrese, Diego; Pfaff, Dennis; Amatruda, Nunzia; Amicarella, Francesca; Kvinlaug, Brynn; Bocelli-Tyndall, Chiara; Martin, Ivan; Resink, Therese J; Heberer, Michael; Oertli, Daniel; Terracciano, Luigi; Spagnoli, Giulio C; Iezzi, Giandomenica
2014-06-01
Mesenchymal stem/stromal cells (MSC) are multipotent precursors endowed with the ability to home to primary and metastatic tumor sites, where they can integrate into the tumor-associated stroma. However, molecular mechanisms and outcome of their interaction with cancer cells have not been fully clarified. In this study, we investigated the effects mediated by bone marrow-derived MSC on human colorectal cancer (CRC) cells in vitro and in vivo. We found that MSC triggered epithelial-to-mesenchymal transition (EMT) in tumor cells in vitro, as indicated by upregulation of EMT-related genes, downregulation of E-cadherin and acquisition of mesenchymal morphology. These effects required cell-to-cell contact and were mediated by surface-bound TGF-β newly expressed on MSC upon coculture with tumor cells. In vivo tumor masses formed by MSC-conditioned CRC cells were larger and characterized by higher vessel density, decreased E-cadherin expression and increased expression of mesenchymal markers. Furthermore, MSC-conditioned tumor cells displayed increased invasiveness in vitro and enhanced capacity to invade peripheral tissues in vivo. Thus, by promoting EMT-related phenomena, MSC appear to favor the acquisition of an aggressive phenotype by CRC cells. © 2013 The Authors. Published by Wiley Periodicals, Inc. on behalf of UICC.
Energy Technology Data Exchange (ETDEWEB)
Pope, M.C.; Read, J.F. (Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Dept. of Geology)
1994-03-01
Passive margin, cyclic carbonates of the Early Ordovician Knox Group, Appalachians are dominated by meter scale dolomitized carbonate cycles. These are stacked into 1 to 5 m.y. depositional sequences that appear to be relatively conformable. The sequences are defined by stacking patterns on Fischer plots that graph long term changes in accommodation with thick less dolomitized cycles in the TST, and thin, highly dolomitized cycles in the HST, becoming quartzose in the late HST and LST. Sequence and systems tract boundaries are subtle and typically marked by zones of cycles rather than single discrete surfaces. In contrast, sequences in the later Ordovician foreland basin fill locally show: (1) sequence bounding unconformities on the Knox, the Camp Nelson and on top of the Ordovician, (2) well defined low stand deposits as in the subaerial breccias and detrital dolomite muds veneering the Knox unconformity; redbeds and associated quartz sands and conglomerates with intercalated peritidal carbonate layers and their distal equivalent peritidal laminites; (3) TST's in the lower part of the Middle Ordovician limestones include regionally traceable cyclic peritidal carbonates or in the lower Lexington Limestone, transgressive high energy grainstones; (4) HST's consist of poorly cyclic deeper water up into shallow water grainstone bank and northward prograding peritidal carbonate facies; The ongoing study of detailed logs of outcrop and core should help refine the understanding of the fine scale makeup of sequences developed in these contrasting tectonic and global climatic settings.
Yu, Changmin; Zeng, Fang; Luo, Ming; Wu, Shuizhu
2012-08-01
Biothiols play crucial roles in maintaining biological systems; among them, homocysteine (Hcy) has received increasing attention since elevated levels of Hcy have been implicated as an independent risk factor for cardiovascular disease. Hence, the selective detection of this specific biothiol, which is a disease-associated biomarker, is very important. In this paper, we demonstrate a new mesoporous silica nanoparticle-based sensor for selective detection of homocysteine from biothiols and other common amino acids. In this fluorescent sensing system, an anthracene nitroolefin compound was placed inside the mesopores of mesoporous silica nanoparticles (MSNs) and used as a probe for thiols. The hydrophilic polyethylene glycol (PEG 5000) molecules were covalently bound to the MSN surface and used as a selective barrier for Hcy detection via different interactions between biothiols and the PEG polymer chains. The sensor can discriminate Hcy from the two low-molecular mass biothiols (GSH and Cys) and other common amino acids in totally aqueous media as well as in serum, with a detection limit of 0.1 μM. This strategy may offer an approach for designing other MSN-based sensing systems by using polymers as diffusion regulators in sensing assays for other analytes.
Fabre, Bruno
2010-12-21
The combination of monocrystalline silicon's well-defined structure and the ability to prepare hydrogen-terminated surfaces (Si-H) easily and reproducibly has made this material a very attractive substrate for immobilizing functional molecules. The functionalization of Si-H using the covalent attachment of organic monolayers has received intense attention due to the numerous potential applications of controlled and robust organic/Si interfaces. Researchers have investigated these materials in diverse fields such as molecular electronics, chemistry, and bioanalytical chemistry. Applications include the preparation of surface insulators, the incorporation of chemical or biochemical functionality at interfaces for use in photovoltaic conversion, and the development of new chemical and biological sensing devices. Unlike those of gold, silicon's electronic properties are tunable, and researchers can directly integrate silicon-based devices within electronic circuitry. Moreover, the technological processes used for the micro- and nanopatterning of silicon are numerous and mature enough for producing highly miniaturized functional electronic components. In this Account, we describe a powerful approach that integrates redox-active molecules, such as ferrocene, onto silicon toward electrically addressable systems devoted to information storage or transfer. Ferrocene exhibits attractive electrochemical characteristics: fast electron-transfer rate, low oxidation potential, and two stable redox states (neutral ferrocene and oxidized ferrocenium). Accordingly, ferrocene-modified silicon surfaces could be used as charge storage components with the bound ferrocene center as the memory element. Upon application of a positive potential to silicon, ferrocene is oxidized to its corresponding ferrocenium form. This redox change is equivalent to the change of a bit of information from the "0" to "1" state. To erase the stored charge and return the device to its initial state, a low
Energy Technology Data Exchange (ETDEWEB)
Rouquerol, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1964-11-01
This study is concerned with the bound water of several oxides (beryllia, alumina, silica-alumina) at different steps of their dehydration (heating temperatures between 150 and 1100 deg. C). The following techniques have been used simultaneously: Thermal analysis (a new method has been developed), nitrogen adsorption (study of the texture), Diborane hydrolysis (qualitative and quantitative analysis of surface water), Infra-red spectrography (in the absorption range of water), Nuclear magnetic resonance (in the resonance range of protons). Thanks to these different techniques, five kinds of bound water have been observed. Attention is called on the great influence of the thermal treatment conditions on the evolution of the products resulting from the decomposition of alumina {alpha}-trihydrate Al(OH){sub 3} and beryllium {alpha}-hydroxide, in the course of the dehydration. Moreover, the author emphasizes the peculiar properties of the two kinds of oxides (alumina and beryllia) prepared through a new method of treatment under low pressure and constant speed of decomposition. Such particular features concern mainly texture, bound water, and consequently, also catalytic activity. (author) [French] Ce travail porte sur l'eau de constitution de plusieurs oxydes (glucine, alumine, silice-alumine) aux differents degres de leur deshydratation (temperatures de traitement comprises entre 150 et 1100 deg. C). Cette etude met simultanement en oeuvre: l'analyse thermique (proposition d'une nouvelle methode), l'adsorption d'azote (etude de texture), l'hydrolyse du diborane (analyse qualitative et quantitative de l'eau de surface), la spectrographie infra-rouge (dans le domaine d'absorption de l'eau), la resonance magnetique nucleaire (dans le domaine de resonance des protons). A l'aide de ces differentes techniques, cinq formes d'eau de constitution ont ete observees. L'attention est attiree sur la tres grande influence
Mohri, Mehryar; Rostamizadeh, Afshin
2013-01-01
We present a brief survey of existing mistake bounds and introduce novel bounds for the Perceptron or the kernel Perceptron algorithm. Our novel bounds generalize beyond standard margin-loss type bounds, allow for any convex and Lipschitz loss function, and admit a very simple proof.
Circuit lower bounds in bounded arithmetics
Czech Academy of Sciences Publication Activity Database
Pich, Ján
2015-01-01
Roč. 166, č. 1 (2015), s. 29-45 ISSN 0168-0072 R&D Projects: GA AV ČR IAA100190902 Keywords : bounded arithmetic * circuit lower bounds Subject RIV: BA - General Mathematics Impact factor: 0.582, year: 2015 http://www.sciencedirect.com/science/article/pii/S0168007214000888
Energy Technology Data Exchange (ETDEWEB)
Grcar, Joseph F.
2002-02-04
A matrix lower bound is defined that generalizes ideas apparently due to S. Banach and J. von Neumann. The matrix lower bound has a natural interpretation in functional analysis, and it satisfies many of the properties that von Neumann stated for it in a restricted case. Applications for the matrix lower bound are demonstrated in several areas. In linear algebra, the matrix lower bound of a full rank matrix equals the distance to the set of rank-deficient matrices. In numerical analysis, the ratio of the matrix norm to the matrix lower bound is a condition number for all consistent systems of linear equations. In optimization theory, the matrix lower bound suggests an identity for a class of min-max problems. In real analysis, a recursive construction that depends on the matrix lower bound shows that the level sets of continuously differential functions lie asymptotically near those of their tangents.
Physical Uncertainty Bounds (PUB)
Energy Technology Data Exchange (ETDEWEB)
Vaughan, Diane Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Dean L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2015-03-19
This paper introduces and motivates the need for a new methodology for determining upper bounds on the uncertainties in simulations of engineered systems due to limited fidelity in the composite continuum-level physics models needed to simulate the systems. We show that traditional uncertainty quantification methods provide, at best, a lower bound on this uncertainty. We propose to obtain bounds on the simulation uncertainties by first determining bounds on the physical quantities or processes relevant to system performance. By bounding these physics processes, as opposed to carrying out statistical analyses of the parameter sets of specific physics models or simply switching out the available physics models, one can obtain upper bounds on the uncertainties in simulated quantities of interest.
International Nuclear Information System (INIS)
Inoue, J.; Ohtaka, K.
2004-01-01
We study virtual bound states in photonics, which are a vectorial extension of electron virtual bound states. The condition for these states is derived. It is found that the Mie resonant state which satisfies the condition that the size parameter is less than the angular momentum should be interpreted as a photon virtual bound state. In order to confirm the validity of the concept, we compare the photonic density of states, the width of which represents the lifetime of the photon virtual bound states, with numerical results
DEFF Research Database (Denmark)
Emiris, Ioannis Z.; Mourrain, Bernard; Tsigaridas, Elias
2010-01-01
In this paper we derive aggregate separation bounds, named after Davenport-Mahler-Mignotte (DMM), on the isolated roots of polynomial systems, specifically on the minimum distance between any two such roots. The bounds exploit the structure of the system and the height of the sparse (or toric) re...
Bounded Gaussian process regression
DEFF Research Database (Denmark)
Jensen, Bjørn Sand; Nielsen, Jens Brehm; Larsen, Jan
2013-01-01
We extend the Gaussian process (GP) framework for bounded regression by introducing two bounded likelihood functions that model the noise on the dependent variable explicitly. This is fundamentally different from the implicit noise assumption in the previously suggested warped GP framework. We...
Uniqueness of bounded observables
Energy Technology Data Exchange (ETDEWEB)
Navara, M. [Czech Technical Univ., Praha (Czech Republic). Dept. of Math.
1995-09-01
By an application of a new construction technique we construct a {sigma}-orthomodular lattice with a strongly order-determining set of states and two bounded observables whose expectations are equal at each state. This answers negatively the uniqueness problem for bounded observables, formulated by S. Gudder. (orig.).
Quantum Bounded Symmetric Domains
Vaksman, L. L.
2008-01-01
This is Leonid Vaksman's monograph "Quantum bounded symmetric domains" (in Russian), preceded with an English translation of the table of contents and (a part) of the introduction. Quantum bounded symmetric domains are interesting from several points of view. In particular, they provide interesting examples for noncommutative complex analysis (i.e., the theory of subalgebras of C^*-algebars) initiated by W. Arveson.
Bounding species distribution models
Directory of Open Access Journals (Sweden)
Thomas J. STOHLGREN, Catherine S. JARNEVICH, Wayne E. ESAIAS,Jeffrey T. MORISETTE
2011-10-01
Full Text Available Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for “clamping” model extrapolations. We relied on two commonly used modeling approaches: classification and regression tree (CART and maximum entropy (Maxent models, and we tested a simple alteration of the model extrapolations, bounding extrapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5: 642–647, 2011].
Bounding Species Distribution Models
Stohlgren, Thomas J.; Jarnevich, Cahterine S.; Morisette, Jeffrey T.; Esaias, Wayne E.
2011-01-01
Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS) might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for "clamping" model extrapolations. We relied on two commonly used modeling approaches: classification and regression tree (CART) and maximum entropy (Maxent) models, and we tested a simple alteration of the model extrapolations, bounding extrapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suitable habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 (5): 642-647, 2011].
Fabre, B.; Pujari, S.P.; Scheres, L.M.W.; Zuilhof, H.
2014-01-01
The effect of the size of patterns of micropatterned ferrocene (Fc)-functionalized, oxide-free n-type Si(111) surfaces was systematically investigated by electrochemical methods. Microcontact printing with amine-functionalized Fc derivatives was performed on a homogeneous acid fluoride-terminated
Ahrens, M L
1983-07-13
Electrostatic influences upon the enzymatic activity of the (Na+ + K+)-ATPase from ox brain (EC 3.6.1.3) have been studied. (1) The characteristics of the temperature dependence of the activity - the slopes and inflection temperature, Ti, of the Arrhenius plots - have been shown to depend on the total concentration, but not on the specific properties of added monovalent ions. (2) The enzymatic activity has been shown to be subject simultaneously to unspecific and specific influences of alkali-metal ions or NH+4. Ion-specific effects result from different binding constants of complexation between activating ions and enzyme. These stability constants are affected by the formation of an electrical double layer at the membrane surface. With increasing electrostatic screening, the complex formation is destabilized and, as a consequence, the enzymatic activity decreases. (3) This interaction between ion binding and surface electrostatics enables the enzyme to adapt its activity to the actual ionic conditions. This gives rise to a complex net dependence of the enzymatic activity upon the concentrations of activating ions. Such dependencies are analyzed, and an 'activity surface' has been constructed which represents the enzymatic activity as a function of simultaneously varying concentrations of sodium and potassium. The shape of this activity surface is determined by the relations between ion concentrations, surface potential and the resulting stability of the complexation between the activating ions and the enzyme. By means of three-dimensional representation it is demonstrated that the adaptability of the stability constants is of great importance with respect to the maintenance of the optimal ionic concentrations within the living cell. Therefore, by means of the surrounding membrane, the ATPase is provided with a quality, in addition to its substrate specificity and catalytic ability, which is necessary for its function as a transport enzyme.
Kuznetsov, Denis B; Orlova, Ekaterina V; Neschislyaev, Valery A; Volkhin, Igor L; Izmestiev, Igor V; Lunegov, Igor V; Balandina, Alevtina V; Dianova, Dina G
2017-06-01
The research investigates the mechanism of microwave radiation effects on biological characteristics and structural-dynamic parameters of a sensor bioluminescence system. The research objects are a sterile growth medium (fish meal hydrolisate) and a bacterial culture. It has been established that irradiation causes changes of the growth medium spectral properties within the range of 200-350nm. Changes take place in the intensity and character of luminescence, as well as in relaxation parameters of nuclear magnetic resonance, growth characteristics of the bacterial culture, its cellular morphology and surface topology. The research results enabled us to establish the mechanisms of primary molecular processes that occur when the bacterial culture is exposed to microwave radiation. Transformation of the dynamic-structural state of adsorbed water phases on biopolymer surfaces has been found to be the key factor in the mechanism of microwave effects on living and water-containing objects. Copyright © 2017 Elsevier B.V. All rights reserved.
International Nuclear Information System (INIS)
He, M.Y.; Xiong, G.; Toscano, P.J.; Burwell, R.L. Jr.; Marks, T.J.
1985-01-01
Results of a detailed, quantitative investigation are reported of surface chemistry and catalysis involving selected organoactinides and partially dehydroxylated (PDA) or dehydroxylated (DA) alumina supports. For the complexes Cp' 2 M(CH 3 ) 2 and Cp' 2 M(CD 3 ) 2 (Cp' = eta 5 - (CH 3 ) 5 ; M = Th, U), methane-evolving surface reaction pathways are identified as M-CH 3 protonolysis via surface OH (especially on PDA), Cp' H atom abstraction, and intramolecular elimination of methane within M(CH 3 ) 2 units. This latter process is proposed on the basis of methylene transfer to acetone and some olefin metathesis activity to result in Al 3+ -stabilized alkylidenes. Hydogenolysis studies indicate that ca. 25% of the Cp' 2 M(CH 3 ) 2 /DA surface M-CH 3 groups are removable as methane; reduction of methyl chloride to methane confirms the presence of surface M-H groups produced by hydrogenolysis. The Cp' 2 M(CH 3 ) 2 /DA complexes are active catalysts for propylene hydrogenation following a variety of pretreatment conditions, with N/sub t/ approx. = 0.5 s -1 in a flow reactor at -63 0 C (about 10 times more active than typical Pt/SiO 2 catalysts under the same conditions). M = Th and U are comparable in hydrogenation activity, and CO poisoning experiments indicate that ca. 3% of the adsorbed molecules are catalytically active. Cp' 2 M(CH 3 ) 2 complexes on PDA and silica gel are considerably less active catalysts. The Cp' 2 M(CH 3 ) 2 /DA systems are also active catalysts for ethylene polymerization and weakly active for butene isomerization. Experiments with Cp' 2 Th[CH 2 C(CH 3 ) 3 ] 2 and [Cp' 2 Th(μ-H)H] 2 on DA reveal activity for propylene hydrogenation comparable to the Cp' 2 M(CH 3 ) 2 systems. In contrast, more coordinatively saturated Cp 3 UCH 3 and Cp 3 Th(n-C 4 H 9 ) (Cp = eta 5 -C 5 H 5 ) are far less active, while Cp'Th(CH 2 C 6 H 5 ) 3 is far more active (N/sub t/ approx. = 10 s -1 )
Directory of Open Access Journals (Sweden)
Junxia eLu
2014-07-01
Full Text Available Leucine-Rich Amelogenin Protein (LRAP is a member of the amelogenin family of biomineralization proteins, proteins which play a critical role in enamel formation. Recent studies have revealed the structure and orientation of the N- and C-terminus of LRAP bound to hydroxyapatite (HAP, a surface used as an analog of enamel. The structure of one region, K24 to S28, was found to be sensitive to phosphorylation of S16, the only naturally observed site of serine phosphorylation in LRAP, suggesting that K24S28 may sit at a key region of structural flexibility and play a role in the protein’s function. In this work, we investigated the sensitivity of the structure and orientation of this region when bound to HAP as a function of several factors which may vary during enamel formation to influence structure: the ionic strength (0.05 M, 0.15 M, 0.2 M, the calcium concentration (0.07 mM and 0.4 mM, and the surface to which it is binding (HAP and carbonated apatite (CAP, a more direct mimic of enamel. A naturally occurring mutation found in amelogenin (T21I was also investigated. The structure in the K24S28 region of the protein was found to be sensitive to these conditions, with the CAP surface and excess Ca2+ (8:1 [Ca2+]:[LRAP-K24S28(+P] resulting in a tighter helix, while low ionic strength relaxed the helical structure. Higher ionic strength and the point mutation did not result in any structural change in this region. The distance of the backbone of K24 from the surface was most sensitive to excess Ca2+ and in the T21I-mutation. Collectively, these data suggest that phosphorylated LRAP is able to accommodate structural changes while maintaining its interaction with the surface, and provides further evidence of the structural sensitivity of the K24S28 region, a sensitivity that may contribute to function in biomineralization.
Energy Technology Data Exchange (ETDEWEB)
Warne, L.K.; Merewether, K.O.; Chen, K.C.; Jorgenson, R.E.; Morris, M.E.; Solberg, J.E.; Lewis, J.G. [Sandia National Labs., Albuquerque, NM (United States); Derr, W. [Derr Enterprises, Albuquerque, NM (United States)
1996-07-01
Test data on canonical weapon-like fixtures are used to validate previously developed analytical bounding results. The test fixtures were constructed to simulate (but be slightly worse than) weapon ports of entry but have known geometries (and electrical points of contact). The exterior of the test fixtures exhibited exterior resonant enhancement of the incident fields at the ports of entry with magnitudes equal to those of weapon geometries. The interior consisted of loaded transmission lines adjusted to maximize received energy or voltage but incorporating practical weapon geometrical constraints. New analytical results are also presented for bounding the energies associated with multiple bolt joints and for bounding the exterior resonant enhancement of the exciting fields.
Massive Galileon positivity bounds
de Rham, Claudia; Melville, Scott; Tolley, Andrew J.; Zhou, Shuang-Yong
2017-09-01
The EFT coefficients in any gapped, scalar, Lorentz invariant field theory must satisfy positivity requirements if there is to exist a local, analytic Wilsonian UV completion. We apply these bounds to the tree level scattering amplitudes for a massive Galileon. The addition of a mass term, which does not spoil the non-renormalization theorem of the Galileon and preserves the Galileon symmetry at loop level, is necessary to satisfy the lowest order positivity bound. We further show that a careful choice of successively higher derivative corrections are necessary to satisfy the higher order positivity bounds. There is then no obstruction to a local UV completion from considerations of tree level 2-to-2 scattering alone. To demonstrate this we give an explicit example of such a UV completion.
International Nuclear Information System (INIS)
Fjeld, J.G.; Nustad, K.; Michaelsen, T.E.
1992-01-01
The binding parameters of iodine-125-labelled intact monoclonal immunoglobulin G (IgG), F(ab') 2 and Fab' fragments were compared. The study was carried out with the two monoclonal antibodies (MoAbs) K13 and K16 specific for human Ig light chains κ and λ, respectively. When testing the 125 I-MoAbs against monodisperse polymer particles coated with the specific antigens, the K a for the F(ab') 2 fragments were similar to that for IgG, while the K a for the Fab' fragments were reduced to 10%-20% of that for IgG. The number N of effective target sites revealed with Fab' was higher than with F(ab') and IgG, presumably because less surface area is occupied by the small Fab' molecules. The immunoreactive fraction F ranged according to IgG>F(ab') 2 >Fab'. The explanation of the moderate difference between the K a of the monoclonal Fab' and the divalent IgG and F(ab') 2 was that the divalent molecules were not divalently attached to the particles. When testing the same antibody preparations against humanlymphoma cells producing Ig with light chains κ or λ, the binding results were less reliable than when particles were utilised, presumably due to antigen shedding. Different MoAbs vary in their loss of immunoreactivity due to enzymatic degradation and the radiolabelling procedure. The preparation of the radiolabelled fragments should therefore be optimized for each MoAb, and evaluation is necessary before injection. Artificial targets with a low leakage of antigen, like the monodisperse polymer particles here applied, are recommended for the in vitro evaluation of the immunoreactivity of labelled MoAb preparations. (orig.)
Appell, Jürgen; Merentes Díaz, Nelson José
2013-01-01
This monographis a self-contained exposition of the definition and properties of functionsof bounded variation and their various generalizations; the analytical properties of nonlinear composition operators in spaces of such functions; applications to Fourier analysis, nonlinear integral equations, and boundary value problems. The book is written for non-specialists. Every chapter closes with a list of exercises and open problems.
Hoyer, Paul
2017-05-01
Bound state poles in the S-matrix of perturbative QED are generated by the divergence of the expansion in α . The perturbative corrections are necessarily singular when expanding around free, {O}( α ^0 ) in and out states that have no overlap with finite-sized atomic wave functions. Nevertheless, measurables such as binding energies do have well-behaved expansions in powers of α (and log α ). It is desirable to formulate the concept of "lowest order" for gauge theory bound states such that higher order corrections vanish in the α → 0 limit. This may allow to determine a lowest order term for QCD hadrons which incorporates essential features such as confinement and chiral symmetry breaking, and thus can serve as the starting point of a useful perturbative expansion. I discuss a "Born" (no loop, lowest order in \\hbar ) approximation. Born level states are bound by gauge fields which satisfy the classical field equations. Gauss' law determines a distinct field A^0({\\varvec{x}}) for each instantaneous position of the charges. A Poincaré covariant boundary condition for the gluon field leads to a confining potential for q\\bar{q} and qqq states. In frames where the bound state is in motion the classical gauge field is obtained by a Lorentz boost of the rest frame field.
Directory of Open Access Journals (Sweden)
Peter Carr
2017-11-01
Full Text Available Diffusions are widely used in finance due to their tractability. Driftless diffusions are needed to describe ratios of asset prices under a martingale measure. We provide a simple example of a tractable driftless diffusion which also has a bounded state space.
Rutkevich, Sergei B; Diehl, H W
2015-06-01
The O(n) ϕ(4) model on a strip bounded by a pair of planar free surfaces at separation L can be solved exactly in the large-n limit in terms of the eigenvalues and eigenfunctions of a self-consistent one-dimensional Schrödinger equation. The scaling limit of a continuum version of this model is considered. It is shown that the self-consistent potential can be eliminated in favor of scattering data by means of appropriately extended methods of inverse scattering theory. The scattering data (Jost function) associated with the self-consistent potential are determined for the L=∞ semi-infinite case in the scaling regime for all values of the temperature scaling field t=(T-T(c))/T(c) above and below the bulk critical temperature T(c). These results are used in conjunction with semiclassical and boundary-operator expansions and a trace formula to derive exact analytical results for a number of quantities such as two-point functions, universal amplitudes of two excess surface quantities, the universal amplitude difference associated with the thermal singularity of the surface free energy, and potential coefficients. The asymptotic behaviors of the scaled eigenenergies and eigenfunctions of the self-consistent Schrödinger equation as function of x=t(L/ξ(+))(1/ν) are determined for x→-∞. In addition, the asymptotic x→-∞ forms of the universal finite-size scaling functions Θ(x) and ϑ(x) of the residual free energy and the Casimir force are computed exactly to order 1/x, including their x(-1)ln|x| anomalies.
DEFF Research Database (Denmark)
Damgård, Ivan Bjerre; Faust, Sebastian; Mukherjee, Pratyay
2013-01-01
-free information) which can be used to refresh the secret key. We believe that bounded tampering is a meaningful and interesting alternative to avoid known impossibility results and can provide important insights into the security of existing standard cryptographic schemes.......Related key attacks (RKAs) are powerful cryptanalytic attacks where an adversary can change the secret key and observe the effect of such changes at the output. The state of the art in RKA security protects against an a-priori unbounded number of certain algebraic induced key relations, e.......g., affine functions or polynomials of bounded degree. In this work, we show that it is possible to go beyond the algebraic barrier and achieve security against arbitrary key relations, by restricting the number of tampering queries the adversary is allowed to ask for. The latter restriction is necessary...
Meyer, B. K.
In the preceding chapter, we concentrated on the properties of free excitons. These free excitons may move through the sample and hit a trap, a nonradiative or a radiative recombination center. At low temperatures, the latter case gives rise to either deep center luminescence, mentioned in Sect. 7.1 and discussed in detail in Chap. 9, or to the luminescence of bound exciton complexes (BE or BEC). The chapter continues with the most prominent of these BECs, namely A-excitons bound to neutral donors. The next aspects are the more weakly BEs at ionized donors. The Sect. 7.4 treats the binding or localization energies of BEC from a theoretical point of view, while Sect. 7.5 is dedicated to excited states of BECs, which contain either holes from deeper valence bands or an envelope function with higher quantum numbers. The last section is devoted to donor-acceptor pair transitions. There is no section devoted specifically to excitons bound to neutral acceptors, because this topic is still partly controversially discussed. Instead, information on these A0X complexes is scattered over the whole chapter, however, with some special emphasis seen in Sects. 7.1, 7.4, and 7.5.
Steinberg, Peter
2008-06-01
Who is the blog written by? Peter Steinberg is a nuclear physicist at the Brookhaven National Laboratory in New York, US. He is acting project manager of the PHOBOS experiment, which used Brookhaven's Relativistic Heavy Ion Collider (RHIC) to search for unusual events produced during collisions between gold nuclei. He is also involved with the PHENIX experiment, which seeks to discover a new state of matter known as the quark-gluon plasma. In addition to his own blog Entropy Bound, Steinberg is currently blogging on a website that was set up last year to publicize the involvement of US scientists with the Large Hadron Collider (LHC) at CERN.
DEFF Research Database (Denmark)
Faupin, Jeremy; Møller, Jacob Schach; Skibsted, Erik
2011-01-01
We study regularity of bound states pertaining to embedded eigenvalues of a self-adjoint operator H, with respect to an auxiliary operator A that is conjugate to H in the sense of Mourre. We work within the framework of singular Mourre theory which enables us to deal with confined massless Pauli–......–Fierz models, our primary example, and many-body AC-Stark Hamiltonians. In the simpler context of regular Mourre theory, our results boil down to an improvement of results obtained recently in [8, 9]....
Bounding approaches to system identification
Norton, John; Piet-Lahanier, Hélène; Walter, Éric
1996-01-01
In response to the growing interest in bounding error approaches, the editors of this volume offer the first collection of papers to describe advances in techniques and applications of bounding of the parameters, or state variables, of uncertain dynamical systems. Contributors explore the application of the bounding approach as an alternative to the probabilistic analysis of such systems, relating its importance to robust control-system design.
Kucera, Antonin; Slaman, Theodore A.
2007-01-01
We show that there is a low T-upper bound for the class of K-trivial sets, namely those which are weak from the point of view of algorithmic randomness. This result is a special case of a more general characterization of ideals in Δ02 T-degrees for which there is a low T-upper bound.
Bounds for Asian basket options
Deelstra, Griselda; Diallo, Ibrahima; Vanmaele, Michèle
2008-09-01
In this paper we propose pricing bounds for European-style discrete arithmetic Asian basket options in a Black and Scholes framework. We start from methods used for basket options and Asian options. First, we use the general approach for deriving upper and lower bounds for stop-loss premia of sums of non-independent random variables as in Kaas et al. [Upper and lower bounds for sums of random variables, Insurance Math. Econom. 27 (2000) 151-168] or Dhaene et al. [The concept of comonotonicity in actuarial science and finance: theory, Insurance Math. Econom. 31(1) (2002) 3-33]. We generalize the methods in Deelstra et al. [Pricing of arithmetic basket options by conditioning, Insurance Math. Econom. 34 (2004) 55-57] and Vanmaele et al. [Bounds for the price of discrete sampled arithmetic Asian options, J. Comput. Appl. Math. 185(1) (2006) 51-90]. Afterwards we show how to derive an analytical closed-form expression for a lower bound in the non-comonotonic case. Finally, we derive upper bounds for Asian basket options by applying techniques as in Thompson [Fast narrow bounds on the value of Asian options, Working Paper, University of Cambridge, 1999] and Lord [Partially exact and bounded approximations for arithmetic Asian options, J. Comput. Finance 10 (2) (2006) 1-52]. Numerical results are included and on the basis of our numerical tests, we explain which method we recommend depending on moneyness and time-to-maturity.
Tight bounds for break minimization
Brouwer, Andries E.; Post, Gerhard F.; Woeginger, Gerhard
We consider round-robin sports tournaments with n teams and n − 1 rounds. We construct an infinite family of opponent schedules for which every home-away assignment induces at least 1/4 n(n−2) breaks. This construction establishes a matching lower bound for a corresponding upper bound from the
Market Access through Bound Tariffs
DEFF Research Database (Denmark)
Sala, Davide; Schröder, Philipp J.H.; Yalcin, Erdal
on the risk that exporters face in destination markets. The present paper formalizes the underlying interaction of risk, fixed export costs and firms' market entry decisions based on techniques known from the real options literature; doing so we highlight the important role of bound tariffs at the extensive...... margin of trade. We find that bound tariffs are more effective with higher risk destination markets, that a large binding overhang may still command substantial market access, and that reductions in bound tariffs generate effective market access even when bound rates are above current and long......WTO negotiations deal predominantly with bound - besides applied - tariff rates. But, how can reductions in tariffs ceilings, i.e. tariff rates that no exporter may ever actually be confronted with, generate market access? The answer to this question relates to the effects of tariff bindings...
Metabolism of organically bound tritium
International Nuclear Information System (INIS)
Travis, C.C.
1984-01-01
The classic methodology for estimating dose to man from environmental tritium ignores the fact that organically bound tritium in foodstuffs may be directly assimilated in the bound compartment of tissues without previous oxidation. We propose a four-compartment model consisting of a free body water compartment, two organic compartments, and a small, rapidly metabolizing compartment. The utility of this model lies in the ability to input organically bound tritium in foodstuffs directly into the organic compartments of the model. We found that organically bound tritium in foodstuffs can increase cumulative total body dose by a factor of 1.7 to 4.5 times the free body water dose alone, depending on the bound-to-loose ratio of tritium in the diet. Model predictions are compared with empirical measurements of tritium in human urine and tissue samples, and appear to be in close agreement. 10 references, 4 figures, 3 tables
On the Holographic Bound in Newtonian Cosmology
Directory of Open Access Journals (Sweden)
José M. Isidro
2018-01-01
Full Text Available The holographic principle sets an upper bound on the total (Boltzmann entropy content of the Universe at around 10 123 k B ( k B being Boltzmann’s constant. In this work we point out the existence of a remarkable duality between nonrelativistic quantum mechanics on the one hand, and Newtonian cosmology on the other. Specifically, nonrelativistic quantum mechanics has a quantum probability fluid that exactly mimics the behaviour of the cosmological fluid, the latter considered in the Newtonian approximation. One proves that the equations governing the cosmological fluid (the Euler equation and the continuity equation become the very equations that govern the quantum probability fluid after applying the Madelung transformation to the Schroedinger wavefunction. Under the assumption that gravitational equipotential surfaces can be identified with isoentropic surfaces, this model allows for a simple computation of the gravitational entropy of a Newtonian Universe. In a first approximation, we model the cosmological fluid as the quantum probability fluid of free Schroedinger waves. We find that this model Universe saturates the holographic bound. As a second approximation, we include the Hubble expansion of the galaxies. The corresponding Schroedinger waves lead to a value of the entropy lying three orders of magnitude below the holographic bound. Current work on a fully relativistic extension of our present model can be expected to yield results in even better agreement with empirical estimates of the entropy of the Universe.
Combining Alphas via Bounded Regression
Directory of Open Access Journals (Sweden)
Zura Kakushadze
2015-11-01
Full Text Available We give an explicit algorithm and source code for combining alpha streams via bounded regression. In practical applications, typically, there is insufficient history to compute a sample covariance matrix (SCM for a large number of alphas. To compute alpha allocation weights, one then resorts to (weighted regression over SCM principal components. Regression often produces alpha weights with insufficient diversification and/or skewed distribution against, e.g., turnover. This can be rectified by imposing bounds on alpha weights within the regression procedure. Bounded regression can also be applied to stock and other asset portfolio construction. We discuss illustrative examples.
On functions of bounded semivariation
Czech Academy of Sciences Publication Activity Database
Monteiro, Giselle Antunes
2015-01-01
Roč. 40, č. 2 (2015), s. 233-276 ISSN 0147-1937 Institutional support: RVO:67985840 Keywords : semivariation * functions of bounded variation * regulated functions Subject RIV: BA - General Mathematics http://projecteuclid.org/euclid. rae /1491271216
Computational Lower Bounds Using Diagonalization
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 7. Computational Lower Bounds Using Diagonalization - Languages, Turing Machines and Complexity Classes. M V Panduranga Rao. General Article Volume 14 Issue 7 July 2009 pp 682-690 ...
Simulation bounds for system availability
International Nuclear Information System (INIS)
Tietjen, G.L.; Waller, R.A.
1976-01-01
System availability is a dominant factor in the practicality of nuclear power electrical generating plants. A proposed model for obtaining either lower bounds or interval estimates on availability uses observed data on ''n'' failure-to-repair cycles of the system to estimate the parameters in the time-to-failure and time-to-repair models. These estimates are then used in simulating failure/repair cycles of the system. The availability estimate is obtained for each of 5000 samples of ''n'' failure/repair cycles to form a distribution of estimates. Specific percentile points of those simulated distributions are selected as lower simulation bounds or simulation interval bounds for the system availability. The method is illustrated with operational data from two nuclear plants for which an exponential time-to-failure and a lognormal time-to-repair are assumed
Unitarity bound for gluon shadowing
International Nuclear Information System (INIS)
Kopeliovich, B. Z.; Levin, E.; Potashnikova, I. K.; Schmidt, Ivan
2009-01-01
Although at small Bjorken x gluons originated from different nucleons in a nucleus overlap in the longitudinal direction, most of them are still well separated in the transverse plane and therefore cannot fuse. For this reason the gluon density in nuclei cannot drop at small x below a certain bottom bound, which we evaluated in a model independent manner assuming the maximal strength of gluon fusion. We also calculated gluon shadowing in the saturated regime using the Balitsky-Kovchegov equation and found the nuclear ratio to be well above the unitarity bound. The recently updated analysis of parton distributions in nuclei, including BNL Relativistic Heavy Ion Collider (RHIC) data on high-p T hadron production at forward rapidities, led to strong gluon shadowing. Such strong shadowing and therefore the interpretation of the nuclear modification of the p T spectra in dA collisions at RHIC seem to be inconsistent with this unitarity bound.
Bounds for nonlocality distillation protocols
International Nuclear Information System (INIS)
Forster, Manuel
2011-01-01
Nonlocality can be quantified by the violation of a Bell inequality. Since this violation may be amplified by local operations, an alternative measure has been proposed--distillable nonlocality. The alternative measure is difficult to calculate exactly due to the double exponential growth of the parameter space. In this paper, we give a way to bound the distillable nonlocality of a resource by the solutions to a related optimization problem. Our upper bounds are exponentially easier to compute than the exact value and are shown to be meaningful in general and tight in some cases.
Space-bounded communication complexity
DEFF Research Database (Denmark)
Brody, Joshua Eric; Chen, Shiteng; Papakonstantinou, Periklis A.
2013-01-01
In the past thirty years, Communication Complexity has emerged as a foundational tool to proving lower bounds in many areas of computer science. Its power comes from its generality, but this generality comes at a price---no superlinear communication lower bound is possible, since a player may...... communicate his entire input. However, what if the players are limited in their ability to recall parts of their interaction? We introduce memory models for 2-party communication complexity. Our general model is as follows: two computationally unrestricted players, Alice and Bob, each have s(n) bits of memory...
Bound entanglement and local realism
International Nuclear Information System (INIS)
Kaszlikowski, Dagomir; Zukowski, Marek; Gnacinski, Piotr
2002-01-01
We show using a numerical approach, which gives necessary and sufficient conditions for the existence of local realism, that the bound entangled state presented in Bennett et al. [Phys. Rev. Lett. 82, 5385 (1999)] admits a local and realistic description. We also find the lowest possible amount of some appropriate entangled state that must be ad-mixed to the bound entangled state so that the resulting density operator has no local and realistic description and as such can be useful in quantum communication and quantum computation
Market access through bound tariffs
DEFF Research Database (Denmark)
Sala, Davide; Yalcin, Erdal; Schröder, Philipp
2010-01-01
WTO negotiations deal predominantly with bound - besides applied - tariff rates. But, how can reductions in tariffs ceilings, i.e. tariff rates that no exporter may ever actually be confronted with, generate market access? The answer to this question relates to the effects of tariff bindings...... on the risk that exporters face in destination markets. The present paper formalizes the underlying interaction of risk, fixed export costs and firms' market entry decisions based on techniques known from the real options literature; doing so we highlight the important role of bound tariffs at the extensive...
Transient response in granular bounded heap flows
Xiao, Hongyi; Ottino, Julio M.; Lueptow, Richard M.; Umbanhowar, Paul B.
2017-11-01
Heap formation, a canonical granular flow, is common in industry and is also found in nature. Here, we study the transition between steady flow states in quasi-2D bounded heaps by suddenly changing the feed rate from one fixed value to another. During the transition, in both experiments and discrete element method simulations, an additional wedge of flowing particles propagates over the rising free surface. The downstream edge of the wedge - the wedge front - moves downstream with velocity inversely proportional to the square root of time. An additional longer duration transient process continues after the wedge front reaches the downstream wall. The transient flux profile during the entire transition is well modeled by a diffusion-like equation derived from local mass balance and a local linear relation between the flux and the surface slope. Scalings for the transient kinematics during the flow transitions are developed based on the flux profiles. Funded by NSF Grant CBET-1511450.
Entropy Bounds and Field Equations
Directory of Open Access Journals (Sweden)
Alessandro Pesci
2015-08-01
Full Text Available For general metric theories of gravity, we compare the approach that describes/derives the field equations of gravity as a thermodynamic identity with the one which looks at them from entropy bounds. The comparison is made through the consideration of the matter entropy flux across (Rindler horizons, studied by making use of the notion of a limiting thermodynamic scale l* of matter, previously introduced in the context of entropy bounds. In doing this: (i a bound for the entropy of any lump of matter with a given energy-momentum tensor Tab is considered, in terms of a quantity, which is independent of the theory of gravity that we use; this quantity is the variation of the Clausius entropy of a suitable horizon when the element of matter crosses it; (ii by making use of the equations of motion of the theory, the same quantity is then expressed as the variation of Wald’s entropy of that horizon (and this leads to a generalized form of the generalized covariant entropy bound, applicable to general diffeomorphism-invariant theories of gravity; and (iii a notion of l* for horizons, as well as an expression for it, is given.
Bounded Densities and Their Derivatives
DEFF Research Database (Denmark)
Kozine, Igor; Krymsky, V.
2009-01-01
This paper describes how one can compute interval-valued statistical measures given limited information about the underlying distribution. The particular focus is on a bounded derivative of a probability density function and its combination with other available statistical evidence for computing ...
Semiclassical bounds in magnetic bottles
Czech Academy of Sciences Publication Activity Database
Barseghyan, Diana; Exner, Pavel; Kovařík, H.; Weidl, T.
2016-01-01
Roč. 28, č. 1 (2016), s. 1650002 ISSN 0129-055X R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : magnetic Laplacian * discrete spectrum * eigenvalue bounds Subject RIV: BE - Theoretical Physics Impact factor: 1.426, year: 2016
Positivity bounds for Sivers functions
International Nuclear Information System (INIS)
Kang Zhongbo; Soffer, Jacques
2011-01-01
We generalize a positivity constraint derived initially for parity-conserving processes to the parity-violating ones, and use it to derive non-trivial bounds on several Sivers functions, entering in the theoretical description of single spin asymmetry for various processes.
Moderate deviations for bounded subsequences
Directory of Open Access Journals (Sweden)
George Stoica
2006-01-01
Full Text Available We study Davis' series of moderate deviations probabilities for Lp-bounded sequences of random variables (p>2. A certain subseries therein is convergent for the same range of parameters as in the case of martingale difference or i.i.d. sequences.
Pieter Paul Rubens, "Prometheus Bound."
Shoemaker, Marla K.
1986-01-01
Provides a full-color reproduction of Pieter Paul Rubens' painting, "Prometheus Bound," and a lesson plan for using it with students in grades 10 through 12. The goal of the lesson is to introduce students to the techniques of design and execution used by Rubens. (JDH)
Upward Bound: In the Beginning.
Groutt, John; Hill, Calvin
2001-01-01
Describes the early history of the Upward Bound program, including the role of President Johnson's vision, the Task Force on Poverty, the Office of Economic Opportunity, and Community Action Programs; influences on the development of the program; establishment of the program's administrative structure; pilot programs; and early problems leading to…
A Functional Calculus for Quotient Bounded Operators
Directory of Open Access Journals (Sweden)
Sorin Mirel Stoian
2006-12-01
Full Text Available If (X, P is a sequentially locally convex space, then a quotient bounded operator T beloging to QP is regular (in the sense of Waelbroeck if and only if it is a bounded element (in the sense of Allan of algebra QP. The classic functional calculus for bounded operators on Banach space is generalized for bounded elements of algebra QP.
Computer simulation of bounded plasmas
International Nuclear Information System (INIS)
Lawson, W.S.
1987-01-01
The problems of simulating a one-dimensional bounded plasma system using particles in a gridded space are systematically explored and solutions to them are given. Such problems include the injection of particles at the boundaries, the solution of Poisson's equation, and the inclusion of an external circuit between the confining boundaries. A recently discovered artificial cooling effect is explained as being a side-effect of quiet injection, and its potential for causing serious but subtle errors in bounded simulation is noted. The methods described in the first part of the thesis are then applied to the simulation of an extension of the Pierce diode problem, specifically a Pierce diode modified by an external circuit between the electrodes. The results of these simulations agree to high accuracy with theory when a theory exists, and also show some interesting chaotic behavior in certain parameter regimes. The chaotic behavior is described in detail
Bounded Rationality in Transposition Processes
DEFF Research Database (Denmark)
Vollaard, Hans; Martinsen, Dorte Sindbjerg
2014-01-01
Studies explaining the timeliness and correctness of the transposition of EU directives into national legislation have provided rather inconclusive findings. They do not offer a clear-cut prediction concerning the transposition of the patients’ rights directive, which is one of the first that con......Studies explaining the timeliness and correctness of the transposition of EU directives into national legislation have provided rather inconclusive findings. They do not offer a clear-cut prediction concerning the transposition of the patients’ rights directive, which is one of the first...... that concerns the organisation and financing of national healthcare systems. This article applies the perspective of bounded rationality to explain (irregularities in) the timely and correct transposition of EU directives. The cognitive and organisational constraints long posited by the bounded rationality...
2013-03-26
...; Comment Request; Upward Bound and Upward Bound Math Science Annual Performance Report AGENCY: The Office... considered public records. Title of Collection: Upward Bound and Upward Bound Math Science Annual Performance...) and Upward Bound Math and Science (UBMS) Programs. The Department is requesting a new APR because of...
Complexity Bounds for Quantum Computation
2007-06-22
iently thanin lassi al omputation, onstru tion of small ir uits whi h an arry out phase estimation, show-ing that the quantum ontent of strong...on lower bounds for omputing parity or fanout using onstant or log depth quantum ir uits, quantum simulations of lassi al ir uit elements and...lasses, su h as thresh-old and mod fun tions, and the general relationships between quantum omplexity lasses and orre-sponding lassi al lasses
On resonances and bound states of Smilansky Hamiltonian
Czech Academy of Sciences Publication Activity Database
Exner, Pavel; Lotoreichik, Vladimir; Tater, Miloš
2016-01-01
Roč. 7, č. 5 (2016), s. 789-802 ISSN 2220-8054 R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : Smilansky Hamiltonian * resonances * resonance free region * weak coupling asymptotics * Riemann surface * bound states Subject RIV: BE - Theoretical Physics
Dilation volumes of sets of bounded perimeter
DEFF Research Database (Denmark)
Kiderlen, Markus; Rataj, Jan
, this derivative coincides up to sign with the directional derivative of the covariogram of A in direction u. By known results for the covariogram, this derivative can therefore be expressed by the cosine transform of the surface area measure of A. We extend this result to sets Q that are at most countable and use...... it to determine the derivative of the contact distribution function of a stationary random closed set at zero. A variant for uncountable Q is given, too. The proofs are based on approximation of the characteristic function of A by smooth functions of bounded variation and showing corresponding formulas for them....
The algebras of bounded and essentially bounded Lebesgue measurable functions
Directory of Open Access Journals (Sweden)
Mortini Raymond
2017-04-01
Full Text Available Let X be a set in ℝn with positive Lebesgue measure. It is well known that the spectrum of the algebra L∞(X of (equivalence classes of essentially bounded, complex-valued, measurable functions on X is an extremely disconnected compact Hausdorff space.We show, by elementary methods, that the spectrum M of the algebra ℒb(X, ℂ of all bounded measurable functions on X is not extremely disconnected, though totally disconnected. Let ∆ = { δx : x ∈ X} be the set of point evaluations and let g be the Gelfand topology on M. Then (∆, g is homeomorphic to (X, Τdis,where Tdis is the discrete topology. Moreover, ∆ is a dense subset of the spectrum M of ℒb(X, ℂ. Finally, the hull h(I, (which is homeomorphic to M(L∞(X, of the ideal of all functions in ℒb(X, ℂ vanishing almost everywhere on X is a nowhere dense and extremely disconnected subset of the Corona M \\ ∆ of ℒb(X, ℂ.
Bounds on dissipation in stress-driven flow
Tang, W.; Caulfield, C. P.; Young, W. R.
2004-07-01
We calculate the optimal upper and lower bounds, subject to the assumption of streamwise invariance, on the long-time-averaged mechanical energy dissipation rate varepsilon within the flow of an incompressible viscous fluid of constant kinematic viscosity nu and depth h driven by a constant surface stress tau=rho u(2_star) , where u_star is the friction velocity. We show that varepsilon ≤ varepsilon_{max}=tau(2/(rho^2nu)) , i.e. the dissipation is bounded above by the dissipation associated with the laminar solution bu=tau(z+h)/(rhonu) xvec, where xvec is the unit vector in the streamwise x-direction.
Voronoi Diagrams Without Bounding Boxes
Sang, E. T. K.
2015-10-01
We present a technique for presenting geographic data in Voronoi diagrams without having to specify a bounding box. The method restricts Voronoi cells to points within a user-defined distance of the data points. The mathematical foundation of the approach is presented as well. The cell clipping method is particularly useful for presenting geographic data that is spread in an irregular way over a map, as for example the Dutch dialect data displayed in Figure 2. The automatic generation of reasonable cell boundaries also makes redundant a frequently used solution to this problem that requires data owners to specify region boundaries, as in Goebl (2010) and Nerbonne et al (2011).
Sensitivity analysis using probability bounding
International Nuclear Information System (INIS)
Ferson, Scott; Troy Tucker, W.
2006-01-01
Probability bounds analysis (PBA) provides analysts a convenient means to characterize the neighborhood of possible results that would be obtained from plausible alternative inputs in probabilistic calculations. We show the relationship between PBA and the methods of interval analysis and probabilistic uncertainty analysis from which it is jointly derived, and indicate how the method can be used to assess the quality of probabilistic models such as those developed in Monte Carlo simulations for risk analyses. We also illustrate how a sensitivity analysis can be conducted within a PBA by pinching inputs to precise distributions or real values
Rhodium catalysts bound to functionalized mesoporous silica
Energy Technology Data Exchange (ETDEWEB)
Bitterwolf, Thomas E.; Newell, J D.; Carver, Colin T.; Addleman, Raymond S.; Linehan, John C.; Fryxell, Glen E.
2004-07-20
Phosphine and amine functionalized mesoporous silica materials were metallated with Rh(CO)2(i-Pr2NH)Cl or Rh2(CO)4Cl2, respectively, to yield catalysts containing the Rh(PPh2R)2(CO)Cl or Rh(CO)2(NH2R)Cl, where R is a propyl chain bonded to the silica surface, reactive centers. In order to ascertain the effect of pore size on rates of hydroformylation catalysis both 35 and 45 ? pore size materials were used. Using the hydroformylation of octene as a reference reaction, the phosphine based, 45 ? catalysts were 1.5-1.3 times faster than the amine based, 45 ? materials were 2.6-2.1 times faster than the 35 ? catalysts, and the 45 ? materials. The orientation of the catalyst relative to the functionalized surface, and the steric environment around the catalyst active site appear to be significant in determining rate of reaction. The ability of the surface bound phosphine catalysts to affect hydroformylation was strongly influenced by the steric constraints of the substrate. Terminal alkenes were readily hydroformylated and norbornene was slowly hydroformylated, but pinene, trans-cyclododecene, cyclohexene and cholesterol were nonreactive to the catalytic center.
Substrate-Bound Protein Gradients to Study Haptotaxis
Directory of Open Access Journals (Sweden)
Sebastien G. Ricoult
2015-03-01
Full Text Available Cells navigate in response to inhomogeneous distributions of extracellular guidance cues. The cellular and molecular mechanisms underlying migration in response to gradients of chemical cues have been investigated for over a century. Following the introduction of micropipettes and more recently microfluidics for gradient generation, much attention and effort was devoted to study cellular chemotaxis, which is defined as guidance by gradients of chemical cues in solution. Haptotaxis, directional migration in response to gradients of substrate-bound cues, has received comparatively less attention; however it is increasingly clear that in vivo many physiologically relevant guidance proteins – including many secreted cues – are bound to cellular surfaces or incorporated into extracellular matrix and likely function via a haptotactic mechanism. Here, we review the history of haptotaxis. We examine the importance of the reference surface, the surface in contact with the cell that is not covered by the cue, which forms a gradient opposing the gradient of the protein cue and must be considered in experimental designs and interpretation of results. We review and compare microfluidics, contact-printing, light patterning and 3D fabrication to pattern substrate-bound protein gradients in vitro, and focus on their application to study axon guidance. The range of methods to create substrate-bound gradients discussed herein make possible systematic analyses of haptotactic mechanisms. Furthermore, understanding the fundamental mechanisms underlying cell motility will inform bioengineering approaches to program cell navigation and recover lost function.
Determining Normal-Distribution Tolerance Bounds Graphically
Mezzacappa, M. A.
1983-01-01
Graphical method requires calculations and table lookup. Distribution established from only three points: mean upper and lower confidence bounds and lower confidence bound of standard deviation. Method requires only few calculations with simple equations. Graphical procedure establishes best-fit line for measured data and bounds for selected confidence level and any distribution percentile.
Observational Bounds on Cosmic Doomsday
Energy Technology Data Exchange (ETDEWEB)
Shmakova, Marina
2003-07-11
Recently it was found, in a broad class of models, that the dark energy density may change its sign during the evolution of the universe. This may lead to a global collapse of the universe within the time t{sub c} {approx} 10{sup 10}-10{sup 11} years. Our goal is to find what bounds on the future lifetime of the universe can be placed by the next generation of cosmological observations. As an example, we investigate the simplest model of dark energy with a linear potential V({phi}) = V{sub 0}(1 + {alpha}{phi}). This model can describe the present stage of acceleration of the universe if {alpha} is small enough. However, eventually the field {phi} rolls down, V({phi}) becomes negative, and the universe collapses. The existing observational data indicate that the universe described by this model will collapse not earlier than t{sub c} {approx_equal} 10 billion years from the present moment. We show that the data from SNAP and Planck satellites may extend the bound on the ''doomsday'' time to tc 40 billion years at the 95% confidence level.
Quantum bounds on Bell inequalities
Pál, Károly F.; Vértesi, Tamás
2009-02-01
We have determined the maximum quantum violation of 241 tight bipartite Bell inequalities with up to five two-outcome measurement settings per party by constructing the appropriate measurement operators in up to six-dimensional complex and eight-dimensional real-component Hilbert spaces using numerical optimization. Out of these inequalities 129 have been introduced here. In 43 cases higher-dimensional component spaces gave larger violation than qubits, and in three occasions the maximum was achieved with six-dimensional spaces. We have also calculated upper bounds on these Bell inequalities using a method proposed recently. For all but 20 inequalities the best solution found matched the upper bound. Surprisingly, the simplest inequality of the set examined, with only three measurement settings per party, was not among them, despite the high dimensionality of the Hilbert space considered. We also computed detection threshold efficiencies for the maximally entangled qubit pair. These could be lowered in several instances if degenerate measurements were also allowed.
Normalization constraint for variational bounds on fluid permeability
International Nuclear Information System (INIS)
Berryman, J.G.; Milton, G.W.
1985-01-01
A careful reexamination of the formulation of Prager's original variational principle for viscous flow through porous media has uncovered a subtle error in the normalization constraint on the trial functions. Although a certain surface integral of the true pressure field over the internal surface area always vanishes for isotropic materials, the corresponding surface integral for a given trial pressure field does not necessarily vanish but has nevertheless been previously neglected in the normalization. When this error is corrected, the form of the variational estimate is actually simpler than before and furthermore the resulting bounds have been shown to improve when the constant trial functions are used in either the two-point or three-point bounds
Holography, Dimensional Reduction and the Bekenstein Bound
Bak, Dongsu; Yee, Ho-Ung
2004-04-01
We consider dimensional reduction of the lightlike holography of the covariant entropy bound from D+1 dimensional geometry of M × S1 to the D dimensional geometry M. With a warping factor, the local Bekenstein bound in D+1 dimensions leads to a more refined form of the bound from the D dimensional view point. With this new local Bekenstein bound, it is quite possible to saturate the lightlike holography even with nonvanishing expansion rate. With a Kaluza-Klein gauge field, the dimensional reduction implies a stronger bound where the energy momentum tensor contribution is replaced by the energy momentum tensor with the electromagnetic contribution subtracted.
Capacity Bounds for Parallel Optical Wireless Channels
Chaaban, Anas
2016-01-01
A system consisting of parallel optical wireless channels with a total average intensity constraint is studied. Capacity upper and lower bounds for this system are derived. Under perfect channel-state information at the transmitter (CSIT), the bounds have to be optimized with respect to the power allocation over the parallel channels. The optimization of the lower bound is non-convex, however, the KKT conditions can be used to find a list of possible solutions one of which is optimal. The optimal solution can then be found by an exhaustive search algorithm, which is computationally expensive. To overcome this, we propose low-complexity power allocation algorithms which are nearly optimal. The optimized capacity lower bound nearly coincides with the capacity at high SNR. Without CSIT, our capacity bounds lead to upper and lower bounds on the outage probability. The outage probability bounds meet at high SNR. The system with average and peak intensity constraints is also discussed.
On order bounded subsets of locally solid Riesz spaces | Hong ...
African Journals Online (AJOL)
In a topological Riesz space there are two types of bounded subsets: order bounded subsets and topologically bounded subsets. It is natural to ask (1) whether an order bounded subset is topologically bounded and (2) whether a topologically bounded subset is order bounded. A classical result gives a partial answer to (1) ...
VORONOI DIAGRAMS WITHOUT BOUNDING BOXES
Directory of Open Access Journals (Sweden)
E. T. K. Sang
2015-10-01
Full Text Available We present a technique for presenting geographic data in Voronoi diagrams without having to specify a bounding box. The method restricts Voronoi cells to points within a user-defined distance of the data points. The mathematical foundation of the approach is presented as well. The cell clipping method is particularly useful for presenting geographic data that is spread in an irregular way over a map, as for example the Dutch dialect data displayed in Figure 2. The automatic generation of reasonable cell boundaries also makes redundant a frequently used solution to this problem that requires data owners to specify region boundaries, as in Goebl (2010 and Nerbonne et al (2011.
Cosmological bounds on neutrino statistics
de Salas, P. F.; Gariazzo, S.; Laveder, M.; Pastor, S.; Pisanti, O.; Truong, N.
2018-03-01
We consider the phenomenological implications of the violation of the Pauli exclusion principle for neutrinos, focusing on cosmological observables such as the spectrum of Cosmic Microwave Background anisotropies, Baryon Acoustic Oscillations and the primordial abundances of light elements. Neutrinos that behave (at least partly) as bosonic particles have a modified equilibrium distribution function that implies a different influence on the evolution of the Universe that, in the case of massive neutrinos, can not be simply parametrized by a change in the effective number of neutrinos. Our results show that, despite the precision of the available cosmological data, only very weak bounds can be obtained on neutrino statistics, disfavouring a more bosonic behaviour at less than 2σ.
Fundamental Bounds on MIMO Antennas
Ehrenborg, Casimir; Gustafsson, Mats
2018-01-01
Antenna current optimization is often used to analyze the optimal performance of antennas. Antenna performance can be quantified in e.g., minimum Q-factor and efficiency. The performance of MIMO antennas is more involved and, in general, a single parameter is not sufficient to quantify it. Here, the capacity of an idealized channel is used as the main performance quantity. An optimization problem in the current distribution for optimal capacity, measured in spectral efficiency, given a fixed Q-factor and efficiency is formulated as a semi-definite optimization problem. A model order reduction based on characteristic and energy modes is employed to improve the computational efficiency. The performance bound is illustrated by solving the optimization problem numerically for rectangular plates and spherical shells.
Spectral computations for bounded operators
Ahues, Mario; Limaye, Balmohan
2001-01-01
Exact eigenvalues, eigenvectors, and principal vectors of operators with infinite dimensional ranges can rarely be found. Therefore, one must approximate such operators by finite rank operators, then solve the original eigenvalue problem approximately. Serving as both an outstanding text for graduate students and as a source of current results for research scientists, Spectral Computations for Bounded Operators addresses the issue of solving eigenvalue problems for operators on infinite dimensional spaces. From a review of classical spectral theory through concrete approximation techniques to finite dimensional situations that can be implemented on a computer, this volume illustrates the marriage of pure and applied mathematics. It contains a variety of recent developments, including a new type of approximation that encompasses a variety of approximation methods but is simple to verify in practice. It also suggests a new stopping criterion for the QR Method and outlines advances in both the iterative refineme...
Bound anionic states of adenine
Energy Technology Data Exchange (ETDEWEB)
Haranczyk, Maciej; Gutowski, Maciej S; Li, Xiang; Bowen, Kit H
2007-03-20
Anionic states of nucleic acid bases are involved in DNA damage by low-energy electrons and in charge transfer through DNA. Previous gas phase studies of free, unsolvated nucleic acid base parent anions probed only dipole-bound states, which are not present in condensed phase environments, but did not observe valence anionic states, which for purine bases, are thought to be adiabatically unbound. Contrary to this expectation, we have demonstrated that some thus far ignored tautomers of adenine, which result from enamine-imine transformations, support valence anionic states with electron vertical detachment energies as large as 2.2 eV, and at least one of these anionic tautomers is adiabatically bound. Moreover, we predict that the new anionic tautomers should also dominate in solutions and should be characterized by larger values of electron vertical detachment energy than the canonical valence anion. All of the new-found anionic tautomers might be formed in the course of dissociative electron attachment followed by a hydrogen atom attachment to a carbon atom, and they might affect the structure and properties of DNA and RNA exposed to low-energy electrons. The discovery of these valence anionic states of adenine was facilitated by the development of: (i) a new experimental method for preparing parent anions of nucleic acid bases for photoelectron experiments, and (ii) a new combinatorial/ quantum chemical approach for identification of the most stable tautomers of organic molecules. The computational portion of this work was supported by the: (i) Polish State Committee for Scientific Research (KBN) Grants: DS/8000-4-0140-7 (M.G.) and N204 127 31/2963 (M.H.), (ii) European Social Funds (EFS) ZPORR/2.22/II/2.6/ARP/U/2/05 (M.H.), and (iii) US DOE Office of Biological and Environmental Research, Low Dose Radiation Research Program (M.G.). M.H. holds the Foundation for Polish Science (FNP) award for young scientists. The calculations were performed at the Academic
Instanton bound states in ABJM theory
Energy Technology Data Exchange (ETDEWEB)
Hatsuda, Yasuyuki [DESY Hamburg (Germany). Theory Group; Tokyo Institute of Technology (Japan). Dept. of Physics; Moriyama, Sanefumi [Nagoya Univ. (Japan). Kobayashi Maskawa Inst. and Graduate School of Mathematics; Okuyama, Kazumi [Shinshu Univ., Matsumoto, Nagano (Japan). Dept. of Physics
2013-06-15
The partition function of the ABJM theory receives non-perturbative corrections due to instanton effects. We study these non-perturbative corrections, including bound states of worldsheet instantons and membrane instantons, in the Fermi-gas approach. We require that the total non-perturbative correction should be always finite for arbitrary Chern-Simons level. This finiteness is realized quite non-trivially because each bound state contribution naively diverges at some levels. The poles of each contribution should be canceled out in total. We use this pole cancellation mechanism to find unknown bound state corrections from known ones. We conjecture a general expression of the bound state contribution. Summing up all the bound state contributions, we find that the effect of bound states is simply incorporated into the worldsheet instanton correction by a redefinition of the chemical potential in the Fermi-gas system. Analytic expressions of the 3- and 4-membrane instanton corrections are also proposed.
Bounded elements in Locally C*-algebras
International Nuclear Information System (INIS)
El Harti, Rachid
2001-09-01
In order to get more useful information about Locally C*-algebras, we introduce in this paper the notion of bounded elements. First, we study the connection between bounded elements and spectrally bounded elements. Some structural results of Locally C*-algebras are established in Theorems 1 , 2 and 3. As an immediate consequence of Theorem 3, we give a characterization of the connected component of the identity in the group of unitary elements for a Locally C*-algebra. (author)
Boundedly UC spaces: characterisations and preservation | Jain ...
African Journals Online (AJOL)
A metric space (X, d) is called a boundedly UC space if every closed and bounded subset of X is a UC space. A metric space (X, d) is called a UC space if each real-valued continuous function on (X, d) is uniformly continuous. In this paper, we study twenty-two equivalent conditions for a metric space to be a boundedly UC ...
Bounded cohomology of discrete groups
Frigerio, Roberto
2017-01-01
The author manages a near perfect equilibrium between necessary technicalities (always well motivated) and geometric intuition, leading the readers from the first simple definition to the most striking applications of the theory in 13 very pleasant chapters. This book can serve as an ideal textbook for a graduate topics course on the subject and become the much-needed standard reference on Gromov's beautiful theory. -Michelle Bucher The theory of bounded cohomology, introduced by Gromov in the late 1980s, has had powerful applications in geometric group theory and the geometry and topology of manifolds, and has been the topic of active research continuing to this day. This monograph provides a unified, self-contained introduction to the theory and its applications, making it accessible to a student who has completed a first course in algebraic topology and manifold theory. The book can be used as a source for research projects for master's students, as a thorough introduction to the field for graduate student...
Some Improved Nonperturbative Bounds for Fermionic Expansions
Energy Technology Data Exchange (ETDEWEB)
Lohmann, Martin, E-mail: marlohmann@gmail.com [Universita di Roma Tre, Dipartimento di Matematica (Italy)
2016-06-15
We reconsider the Gram-Hadamard bound as it is used in constructive quantum field theory and many body physics to prove convergence of Fermionic perturbative expansions. Our approach uses a recursion for the amplitudes of the expansion, discovered in a model problem by Djokic (2013). It explains the standard way to bound the expansion from a new point of view, and for some of the amplitudes provides new bounds, which avoid the use of Fourier transform, and are therefore superior to the standard bounds for models like the cold interacting Fermi gas.
Vulnerable Derivatives and Good Deal Bounds
DEFF Research Database (Denmark)
Murgoci, Agatha
2013-01-01
a new restriction in the arbitrage free model by setting upper bounds on the Sharpe ratios (SRs) of the assets. The potential prices that are eliminated represent unreasonably good deals. The constraint on the SR translates into a constraint on the stochastic discount factor. Thus, tight pricing bounds......We price vulnerable derivatives – i.e. derivatives where the counterparty may default. These are basically the derivatives traded on the over-the-counter (OTC) markets. Default is modelled in a structural framework. The technique employed for pricing is good deal bounds (GDBs). The method imposes...... in a consistent way. Finally, we numerically analyse the behaviour of the good deal pricing bounds....
Generating substrate bound functional chemokine gradients in vitro
DEFF Research Database (Denmark)
Hjortø, Gertrud Malene; Hansen, Morten; Larsen, Niels Bent
2009-01-01
Microcontact printing (mCP) is employed to generate discontinuous microscale gradients of active fractalkine, a chemokine expressed by endothelial cells near sites of inflammation where it is believed to form concentration gradients descending away from the inflamed area. In vivo, fractalkine is ...... surface-bound chemokines (haptotactic gradients). The use of a capture antibody facilitates control of the orientation of tagged molecules, thereby ensuring a high degree of bio-functionality through correct presentation and reduced protein denaturation....
Modifications of the Bekenstein Bound from Dimensional Reduction of Covariant Entropy Bound
Yee, Ho-Ung
2005-12-01
We consider dimensional reduction of the covariant entropy bound from D + 1 dimensional geometry of M × S1 to the D dimensional geometry M. With a warping factor, the local Bekenstein bound in D + 1 dimensions leads to a more refined form of the local Bekenstein bound from the D dimensional view point. With this new local Bekenstein bound, it is possible to saturate the lightlike holography bound even with nonvanishing expansion rate. With a Kaluza-Klein gauge field, the dimensional reduction implies a stronger bound where the energy momentum tensor contribution is replaced by the energy momentum tensor with the electromagnetic contribution subtracted.
Dynamics of water bound to crystalline cellulose
Energy Technology Data Exchange (ETDEWEB)
O’Neill, Hugh; Pingali, Sai Venkatesh; Petridis, Loukas; He, Junhong; Mamontov, Eugene; Hong, Liang; Urban, Volker; Evans, Barbara; Langan, Paul; Smith, Jeremy C.; Davison, Brian H.
2017-09-19
Interactions of water with cellulose are of both fundamental and technological importance. Here, we characterize the properties of water associated with cellulose using deuterium labeling, neutron scattering and molecular dynamics simulation. Quasi-elastic neutron scattering provided quantitative details about the dynamical relaxation processes that occur and was supported by structural characterization using small-angle neutron scattering and X-ray diffraction. We can unambiguously detect two populations of water associated with cellulose. The first is “non-freezing bound” water that gradually becomes mobile with increasing temperature and can be related to surface water. The second population is consistent with confined water that abruptly becomes mobile at ~260 K, and can be attributed to water that accumulates in the narrow spaces between the microfibrils. Quantitative analysis of the QENS data showed that, at 250 K, the water diffusion coefficient was 0.85 ± 0.04 × 10-10 m2sec-1 and increased to 1.77 ± 0.09 × 10-10 m2sec-1 at 265 K. MD simulations are in excellent agreement with the experiments and support the interpretation that water associated with cellulose exists in two dynamical populations. Our results provide clarity to previous work investigating the states of bound water and provide a new approach for probing water interactions with lignocellulose materials.
Isoperimetric upper bounds for the first eigenvalue
Indian Academy of Sciences (India)
[5] Buser P and Karcher H, Gromov's almost flat manifolds, Société mathématique de. France (1981). [6] Grosjean J F, Upper bounds for the first eigenvalue of the Laplacian on compact submanifolds, Pacific. J. Math. 206 (2002) 93–112. [7] Heintze Ernst, Extinsic upper bounds for λ1, Math. Ann. 280 (1988) 389–402.
No-arbitrage bounds for financial scenarios
DEFF Research Database (Denmark)
Geyer, Alois; Hanke, Michael; Weissensteiner, Alex
2014-01-01
We derive no-arbitrage bounds for expected excess returns to generate scenarios used in financial applications. The bounds allow to distinguish three regions: one where arbitrage opportunities will never exist, a second where arbitrage may be present, and a third, where arbitrage opportunities...
On the range of completely bounded maps
Directory of Open Access Journals (Sweden)
Richard I. Loebl
1978-01-01
Full Text Available It is shown that if every bounded linear map from a C*-algebra α to a von Neumann algebra β is completely bounded, then either α is finite-dimensional or β⫅⊗Mn, where is a commutative von Neumann algebra and Mn is the algebra of n×n complex matrices.
Bound constrained quadratic programming via piecewise
DEFF Research Database (Denmark)
Madsen, Kaj; Nielsen, Hans Bruun; Pinar, M. C.
1999-01-01
We consider the strictly convex quadratic programming problem with bounded variables. A dual problem is derived using Lagrange duality. The dual problem is the minimization of an unconstrained, piecewise quadratic function. It involves a lower bound of lambda/sub 1/ , the smallest eigenvalue...
Stacked spheres and lower bound theorem
Indian Academy of Sciences (India)
BASUDEB DATTA
2011-11-20
Nov 20, 2011 ... Preliminaries. Lower bound theorem. On going work. Definitions. An n-simplex is a convex hull of n + 1 affinely independent points. (called vertices) in some Euclidean space R. N . Stacked spheres and lower bound theorem. Basudeb Datta. Indian Institute of Science. 2 / 27 ...
Exponential Lower Bounds For Policy Iteration
Fearnley, John
2010-01-01
We study policy iteration for infinite-horizon Markov decision processes. It has recently been shown policy iteration style algorithms have exponential lower bounds in a two player game setting. We extend these lower bounds to Markov decision processes with the total reward and average-reward optimality criteria.
Upper Bounds on Numerical Approximation Errors
DEFF Research Database (Denmark)
Raahauge, Peter
2004-01-01
This paper suggests a method for determining rigorous upper bounds on approximationerrors of numerical solutions to infinite horizon dynamic programming models.Bounds are provided for approximations of the value function and the policyfunction as well as the derivatives of the value function...
Bounds in the location-allocation problem
DEFF Research Database (Denmark)
Juel, Henrik
1981-01-01
Develops a family of stronger lower bounds on the objective function value of the location-allocation problem. Solution methods proposed to solve problems in location-allocation; Efforts to develop a more efficient bound solution procedure; Determination of the locations of the sources....
New bounds for multi-dimensional packing
S. Seiden; R. van Stee (Rob)
2001-01-01
textabstractNew upper and lower bounds are presented for a multi-dimensional generalization of bin packing called box packing. Several variants of this problem, including bounded space box packing, square packing, variable sized box packing and resource augmented box packing are also studied. The
Impedance, zero energy wavefunction, and bound states
Martin, A
1977-01-01
The authors show that for the three-dimensional Schrodinger equation without spherical symmetry the existence of a bound state is related to the impossibility of solving a certain equation; it is further shown that some general conditions for the absence of bound states are readily obtained from this property. (13 refs).
Conductivity bound from dirty black holes
Energy Technology Data Exchange (ETDEWEB)
Bitaghsir Fadafan, Kazem, E-mail: bitaghsir@shahroodut.ac.ir
2016-11-10
We propose a lower bound of the dc electrical conductivity in strongly disordered, strongly interacting quantum field theories using holography. We study linear response of black holes with broken translational symmetry in Einstein–Maxwell-dilaton theories of gravity. Using the generalized Stokes equations at the horizon, we derive the lower bound of the electrical conductivity for the dual two dimensional disordered field theory.
New bounds on isotropic Lorentz violation
International Nuclear Information System (INIS)
Carone, Christopher D.; Sher, Marc; Vanderhaeghen, Marc
2006-01-01
Violations of Lorentz invariance that appear via operators of dimension four or less are completely parametrized in the Standard Model Extension (SME). In the pure photonic sector of the SME, there are 19 dimensionless, Lorentz-violating parameters. Eighteen of these have experimental upper bounds ranging between 10 -11 and 10 -32 ; the remaining parameter, k-tilde tr , is isotropic and has a much weaker bound of order 10 -4 . In this Brief Report, we point out that k-tilde tr gives a significant contribution to the anomalous magnetic moment of the electron and find a new upper bound of order 10 -8 . With reasonable assumptions, we further show that this bound may be improved to 10 -14 by considering the renormalization of other Lorentz-violating parameters that are more tightly constrained. Using similar renormalization arguments, we also estimate bounds on Lorentz-violating parameters in the pure gluonic sector of QCD
Bound-free Spectra for Diatomic Molecules
Schwenke, David W.
2012-01-01
It is now recognized that prediction of radiative heating of entering space craft requires explicit treatment of the radiation field from the infrared (IR) to the vacuum ultra violet (VUV). While at low temperatures and longer wavelengths, molecular radiation is well described by bound-bound transitions, in the short wavelength, high temperature regime, bound-free transitions can play an important role. In this work we describe first principles calculations we have carried out for bound-bound and bound-free transitions in N2, O2, C2, CO, CN, NO, and N2+. Compared to bound ]bound transitions, bound-free transitions have several particularities that make them different to deal with. These include more complicated line shapes and a dependence of emission intensity on both bound state diatomic and atomic concentrations. These will be discussed in detail below. The general procedure we used was the same for all species. The first step is to generate potential energy curves, transition moments, and coupling matrix elements by carrying out ab initio electronic structure calculations. These calculations are expensive, and thus approximations need to be made in order to make the calculations tractable. The only practical method we have to carry out these calculations is the internally contracted multi-reference configuration interaction (icMRCI) method as implemented in the program suite Molpro. This is a widely used method for these kinds of calculations, and is capable of generating very accurate results. With this method, we must first of choose which electrons to correlate, the one-electron basis to use, and then how to generate the molecular orbitals.
Surface-bounded growth modeling applied to human mandibles
DEFF Research Database (Denmark)
Andresen, Per Rønsholt; Brookstein, F. L.; Conradsen, Knut
2000-01-01
automatically using shape features and a new algorithm called geometry-constrained diffusion. The semilandmarks are mapped into Procrustes space. Principal component analysis extracts a one-dimensional subspace, which is used to construct a linear growth model. The worst case mean modeling error in a cross...
Protein sequences bound to mineral surfaces persist into deep time
DEFF Research Database (Denmark)
Demarchi, Beatrice; Hall, Shaun; Roncal-Herrero, Teresa
2016-01-01
Proteins persist longer in the fossil record than DNA, but the longevity, survival mechanisms and substrates remain contested. Here, we demonstrate the role of mineral binding in preserving the protein sequence in ostrich (Struthionidae) eggshell, including from the palaeontological sites...
Pluto's Paleoglaciation: Processes and Bounds.
Umurhan, O. M.; Howard, A. D.; White, O. L.; Moore, J. M.; Grundy, W. M.; Schenk, P.; Beyer, R. A.; McKinnon, W. B.; Singer, K. N.; Lauer, T.; Cheng, A. F.; Stern, A.; Weaver, H. A., Jr.; Young, L. A.; Ennico Smith, K.; Olkin, C.
2017-12-01
New Horizons imaging of Pluto's surface shows eroded landscapes reminiscent of assorted glaciated terrains found on the Earth such as alpine valleys, dendritic networks and others. For example, LORRI imaging of fluted craters show radially oriented ridging which also resembles Pluto's washboard terrain. Digital elevation modeling indicates that these down-gradient oriented ridges are about 3-4 km spaced apart with depths ranging from 0.2-0.5 km. Present day glaciation on Pluto is characterized by moving N2 ice blocks presumably riding over a H2O ice bedrock substrate. Assuming Pluto's ancient surface was sculpted by N2 glaciation, what remains a mystery is the specific nature of the glacial erosion mechanism(s) responsible for the observed features. To better resolve this puzzle, we perform landform evolution modeling of several glacial erosion processes known from terrestrial H2O ice glaciation studies. These terrestrial processes, which depend upon whether or not the glacier's base is wet or dry, include quarrying/plucking and fluvial erosion. We also consider new erosional processes (to be described in this presentation) which are unique to the highly insulating character of solid N2 including both phase change induced hydrofracture and geothermally driven basal melt. Until improvements in our knowledge of solid N2's rheology are made available (including its mechanical behavior as a binary/trinary mixture of CH4 and CO), it is difficult to assess with high precision which of the aforementioned erosion mechanisms are responsible for the observed surface etchings. Nevertheless, we consider a model crater surface and examine its erosional development due to flowing N2 glacial ice as built up over time according to N2 deposition rates based on GCM modeling of Pluto's ancient atmosphere. For given erosional mechanism our aim is to determine the permissible ranges of model input parameters (e.g., ice strength, flow rates, grain sizes, quarrying rates, etc.) that best
Directory of Open Access Journals (Sweden)
Erik Svensjö
2014-01-01
Full Text Available Inhibitors of serine peptidases (ISPs expressed by Leishmania major enhance intracellular parasitism in macrophages by targeting neutrophil elastase (NE, a serine protease that couples phagocytosis to the prooxidative TLR4/PKR pathway. Here we investigated the functional interplay between ISP-expressing L. major and the kallikrein-kinin system (KKS. Enzymatic assays showed that NE inhibitor or recombinant ISP-2 inhibited KKS activation in human plasma activated by dextran sulfate. Intravital microscopy in the hamster cheek pouch showed that topically applied L. major promastigotes (WT and Δisp2/3 mutants potently induced plasma leakage through the activation of bradykinin B2 receptors (B2R. Next, using mAbs against kininogen domains, we showed that these BK-precursor proteins are sequestered by L. major promastigotes, being expressed at higher % in the Δisp2/3 mutant population. Strikingly, analysis of the role of kinin pathway in the phagocytic uptake of L. major revealed that antagonists of B2R or B1R reversed the upregulated uptake of Δisp2/3 mutants without inhibiting macrophage internalization of WT L. major. Collectively, our results suggest that L. major ISP-2 fine-tunes macrophage phagocytosis by inhibiting the pericellular release of proinflammatory kinins from surface bound kininogens. Ongoing studies should clarify whether L. major ISP-2 subverts TLR4/PKR-dependent prooxidative responses of macrophages by preventing activation of G-protein coupled B2R/B1R.
Svensjö, Erik; Nogueira de Almeida, Larissa; Vellasco, Lucas; Juliano, Luiz; Scharfstein, Julio
2014-01-01
Inhibitors of serine peptidases (ISPs) expressed by Leishmania major enhance intracellular parasitism in macrophages by targeting neutrophil elastase (NE), a serine protease that couples phagocytosis to the prooxidative TLR4/PKR pathway. Here we investigated the functional interplay between ISP-expressing L. major and the kallikrein-kinin system (KKS). Enzymatic assays showed that NE inhibitor or recombinant ISP-2 inhibited KKS activation in human plasma activated by dextran sulfate. Intravital microscopy in the hamster cheek pouch showed that topically applied L. major promastigotes (WT and Δisp2/3 mutants) potently induced plasma leakage through the activation of bradykinin B2 receptors (B2R). Next, using mAbs against kininogen domains, we showed that these BK-precursor proteins are sequestered by L. major promastigotes, being expressed at higher % in the Δisp2/3 mutant population. Strikingly, analysis of the role of kinin pathway in the phagocytic uptake of L. major revealed that antagonists of B2R or B1R reversed the upregulated uptake of Δisp2/3 mutants without inhibiting macrophage internalization of WT L. major. Collectively, our results suggest that L. major ISP-2 fine-tunes macrophage phagocytosis by inhibiting the pericellular release of proinflammatory kinins from surface bound kininogens. Ongoing studies should clarify whether L. major ISP-2 subverts TLR4/PKR-dependent prooxidative responses of macrophages by preventing activation of G-protein coupled B2R/B1R.
Process interpretation of current entropic bounds
Nardini, Cesare; Touchette, Hugo
2018-01-01
We show for Markov diffusion processes that the quadratic entropic bound, recently derived for the rate functions of nonequilibrium currents, can be seen as being produced by an effective process that creates current fluctuations in a sub-optimal way by modifying only the non-reversible part of the drift or force of the process considered while keeping its reversible part constant. This provides a clear interpretation of the bound in terms of a physical process, which explains, among other things, its relation to the fluctuation relation, linear response, and reversible limits. The existence of more general quadratic bounds, and related uncertainty relations, for physical quantities other than currents is also discussed.
Lower bound for the nuclear kinetic energy
Energy Technology Data Exchange (ETDEWEB)
Dehesa, J.S. (Granada Univ. (Spain). Dept. de Fisica Nuclear); Galvez, F.J. (Granada Univ. (Spain). Dept. de Fisica Teorica)
1985-06-27
We argue that the kinetic energy of a many-fermion system is bounded from below by Kqsup(-2/3)A sup(5/3) /
Remarks on Bousso's covariant entropy bound
Mayo, A E
2002-01-01
Bousso's covariant entropy bound is put to the test in the context of a non-singular cosmological solution of general relativity found by Bekenstein. Although the model complies with every assumption made in Bousso's original conjecture, the entropy bound is violated due to the occurrence of negative energy density associated with the interaction of some the matter components in the model. We demonstrate how this property allows for the test model to 'elude' a proof of Bousso's conjecture which was given recently by Flanagan, Marolf and Wald. This corroborates the view that the covariant entropy bound should be applied only to stable systems for which every matter component carries positive energy density.
Quasi-bound states in continuum
International Nuclear Information System (INIS)
Nakamura, Hiroaki; Hatano, Naomichi; Garmon, Sterling; Petrosky, Tomio
2007-08-01
We report the prediction of quasi-bound states (resonant states with very long lifetimes) that occur in the eigenvalue continuum of propagating states for a wide region of parameter space. These quasi-bound states are generated in a quantum wire with two channels and an adatom, when the energy bands of the two channels overlap. A would-be bound state that lays just below the upper energy band is slightly destabilized by the lower energy band and thereby becomes a resonant state with a very long lifetime (a second QBIC lays above the lower energy band). (author)
Tight Bounds for Distributed Functional Monitoring
DEFF Research Database (Denmark)
Woodruff, David P.; Zhang, Qin
2011-01-01
$, our bound resolves their main open question. Our lower bounds are based on new direct sum theorems for approximate majority, and yield significant improvements to problems in the data stream model, improving the bound for estimating $F_p, p > 2,$ in $t$ passes from $\\tilde{\\Omega}(n^{1-2/p}/(\\eps^{2/p......} t))$ to $\\tilde{\\Omega}(n^{1-2/p}/(\\eps^{4/p} t))$, giving the first bound for estimating $F_0$ in $t$ passes of $\\Omega(1/(\\eps^2 t))$ bits of space that does not use the gap-hamming problem, and showing a distribution for the gap-hamming problem with high external information cost or super-polynomial......We resolve several fundamental questions in the area of distributed functional monitoring, initiated by Cormode, Muthukrishnan, and Yi (SODA, 2008). In this model there are $k$ sites each tracking their input and communicating with a central coordinator that continuously maintain an approximate...
Numerical Bounds on the Price of Anarchy
Directory of Open Access Journals (Sweden)
Louis de Grange
2017-01-01
Full Text Available Theoretical upper bounds for price of anarchy have been calculated in previous studies. We present an empirical analysis for the price of anarchy for congested transportation networks; different network sizes and demand levels are considered for each network. We obtain a maximum price of anarchy for the cases studied, which is notably lower than the theoretical bounds reported in the literature. This result should be carefully considered in the design and implementation of road pricing mechanisms for cities.
Learning Intelligent Dialogs for Bounding Box Annotation
Konyushkova, Ksenia; Uijlings, Jasper; Lampert, Christoph; Ferrari, Vittorio
2017-01-01
We introduce Intelligent Annotation Dialogs for bounding box annotation. We train an agent to automatically choose a sequence of actions for a human annotator to produce a bounding box in a minimal amount of time. Specifically, we consider two actions: box verification [37], where the annotator verifies a box generated by an object detector, and manual box drawing. We explore two kinds of agents, one based on predicting the probability that a box will be positively verified, and the other bas...
New Spectral Features from Bound Dark Matter
DEFF Research Database (Denmark)
Catena, Riccardo; Kouvaris, Chris
2016-01-01
We demonstrate that dark matter particles gravitationally bound to the Earth can induce a characteristic nuclear recoil signal at low energies in direct detection experiments. The new spectral feature we predict can provide the ultimate smoking gun for dark matter discovery for experiments...... with positive signal but unclear background. The new feature is universal, in that the ratio of bound over halo dark matter event rates at detectors is independent of the dark matter-nucleon cross section....
Error Bounds: Necessary and Sufficient Conditions
Czech Academy of Sciences Publication Activity Database
Outrata, Jiří; Kruger, A.Y.; Fabian, Marián; Henrion, R.
2010-01-01
Roč. 18, č. 2 (2010), s. 121-149 ISSN 1877-0533 R&D Projects: GA AV ČR IAA100750802 Institutional research plan: CEZ:AV0Z10750506; CEZ:AV0Z10190503 Keywords : Error bounds * Calmness * Subdifferential * Slope Subject RIV: BA - General Mathematics Impact factor: 0.333, year: 2010 http://library.utia.cas.cz/separaty/2010/MTR/outrata-error bounds necessary and sufficient conditions.pdf
Covalently bound conjugates of albumin and heparin: Synthesis, fractionation and characterization
Hennink, Wim E.; Feijen, Jan; Ebert, Charles D.; Kim, Sung Wan
1983-01-01
Covalently bound conjugates of human serum albumin and heparin were prepared as compounds which could improve the blood-compatibility of polymer surfaces either by preadsorption or by covalent coupling of the conjugates onto blood contacting surfaces. The conjugates (10–16 weight % of heparin) were
Lower Bounds on Q for Finite Size Antennas of Arbitrary Shape
DEFF Research Database (Denmark)
Kim, Oleksiy S.
2016-01-01
The problem of the lower bound on the radiation Q for an arbitrarily shaped finite size antenna of non-zero volume is formulated in terms of equivalent electric and magnetic currents densities distributed on a closed surface coinciding with antenna exterior surface. When these equivalent currents...
Error bounds from extra precise iterative refinement
Energy Technology Data Exchange (ETDEWEB)
Demmel, James; Hida, Yozo; Kahan, William; Li, Xiaoye S.; Mukherjee, Soni; Riedy, E. Jason
2005-02-07
We present the design and testing of an algorithm for iterative refinement of the solution of linear equations, where the residual is computed with extra precision. This algorithm was originally proposed in the 1960s [6, 22] as a means to compute very accurate solutions to all but the most ill-conditioned linear systems of equations. However two obstacles have until now prevented its adoption in standard subroutine libraries like LAPACK: (1) There was no standard way to access the higher precision arithmetic needed to compute residuals, and (2) it was unclear how to compute a reliable error bound for the computed solution. The completion of the new BLAS Technical Forum Standard [5] has recently removed the first obstacle. To overcome the second obstacle, we show how a single application of iterative refinement can be used to compute an error bound in any norm at small cost, and use this to compute both an error bound in the usual infinity norm, and a componentwise relative error bound. We report extensive test results on over 6.2 million matrices of dimension 5, 10, 100, and 1000. As long as a normwise (resp. componentwise) condition number computed by the algorithm is less than 1/max{l_brace}10,{radical}n{r_brace} {var_epsilon}{sub w}, the computed normwise (resp. componentwise) error bound is at most 2 max{l_brace}10,{radical}n{r_brace} {center_dot} {var_epsilon}{sub w}, and indeed bounds the true error. Here, n is the matrix dimension and w is single precision roundoff error. For worse conditioned problems, we get similarly small correct error bounds in over 89.4% of cases.
Upper bounds on superpartner masses from upper bounds on the Higgs boson mass.
Cabrera, M E; Casas, J A; Delgado, A
2012-01-13
The LHC is putting bounds on the Higgs boson mass. In this Letter we use those bounds to constrain the minimal supersymmetric standard model (MSSM) parameter space using the fact that, in supersymmetry, the Higgs mass is a function of the masses of sparticles, and therefore an upper bound on the Higgs mass translates into an upper bound for the masses for superpartners. We show that, although current bounds do not constrain the MSSM parameter space from above, once the Higgs mass bound improves big regions of this parameter space will be excluded, putting upper bounds on supersymmetry (SUSY) masses. On the other hand, for the case of split-SUSY we show that, for moderate or large tanβ, the present bounds on the Higgs mass imply that the common mass for scalars cannot be greater than 10(11) GeV. We show how these bounds will evolve as LHC continues to improve the limits on the Higgs mass.
Bounds on poloidal kinetic energy in plane layer convection
Tilgner, A.
2017-12-01
A numerical method is presented that conveniently computes upper bounds on heat transport and poloidal energy in plane layer convection for infinite and finite Prandtl numbers. The bounds obtained for the heat transport coincide with earlier results. These bounds imply upper bounds for the poloidal energy, which follow directly from the definitions of dissipation and energy. The same constraints used for computing upper bounds on the heat transport lead to improved bounds for the poloidal energy.
Better Bounds on Online Unit Clustering
Ehmsen, Martin R.; Larsen, Kim S.
Unit Clustering is the problem of dividing a set of points from a metric space into a minimal number of subsets such that the points in each subset are enclosable by a unit ball. We continue work initiated by Chan and Zarrabi-Zadeh on determining the competitive ratio of the online version of this problem. For the one-dimensional case, we develop a deterministic algorithm, improving the best known upper bound of 7/4 by Epstein and van Stee to 5/3. This narrows the gap to the best known lower bound of 8/5 to only 1/15. Our algorithm automatically leads to improvements in all higher dimensions as well. Finally, we strengthen the deterministic lower bound in two dimensions and higher from 2 to 13/6.
Experimental bounds on sterile neutrino mixing angles
Ruchayskiy, Oleg
2012-01-01
We derive bounds on the mixing between the left-chiral ("active") and the right-chiral ("sterile") neutrinos, provided from the combination of neutrino oscillation data and direct experimental searches for sterile neutrinos. We demonstrate that the mixing of sterile neutrinos with any flavour can be significantly suppressed, provided that the angle theta_13 is non-zero. This means that the lower bounds on sterile neutrino lifetime, coming from the negative results of direct experimental searches can be relaxed (by as much as the order of magnitude at some masses). We also demonstrate that the results of the negative searches of sterile neutrinos with PS191 and CHARM experiments are not applicable directly to the see-saw models. The reinterpretation of these results provides up to the order of magnitude stronger bounds on sterile neutrino lifetime than previously discussed in the literature. We discuss the implications of our results for the Neutrino Minimal Standard Model (the NuMSM).
Bounded Gaps between Products of Special Primes
Directory of Open Access Journals (Sweden)
Ping Ngai Chung
2014-03-01
Full Text Available In their breakthrough paper in 2006, Goldston, Graham, Pintz and Yıldırım proved several results about bounded gaps between products of two distinct primes. Frank Thorne expanded on this result, proving bounded gaps in the set of square-free numbers with r prime factors for any r ≥ 2, all of which are in a given set of primes. His results yield applications to the divisibility of class numbers and the triviality of ranks of elliptic curves. In this paper, we relax the condition on the number of prime factors and prove an analogous result using a modified approach. We then revisit Thorne’s applications and give a better bound in each case.
Properties of Water Bound in Hydrogels
Directory of Open Access Journals (Sweden)
Vladimir M. Gun’ko
2017-10-01
Full Text Available In this review, the importance of water in hydrogel (HG properties and structure is analyzed. A variety of methods such as 1H NMR (nuclear magnetic resonance, DSC (differential scanning calorimetry, XRD (X-ray powder diffraction, dielectric relaxation spectroscopy, thermally stimulated depolarization current, quasi-elastic neutron scattering, rheometry, diffusion, adsorption, infrared spectroscopy are used to study water in HG. The state of HG water is rather non-uniform. According to thermodynamic features of water in HG, some of it is non-freezing and strongly bound, another fraction is freezing and weakly bound, and the third fraction is non-bound, free water freezing at 0 °C. According to structural features of water in HG, it can be divided into two fractions with strongly associated and weakly associated waters. The properties of the water in HG depend also on the amounts and types of solutes, pH, salinity, structural features of HG functionalities.
Yukawa Bound States and Their LHC Phenomenology
Directory of Open Access Journals (Sweden)
Enkhbat Tsedenbaljir
2013-01-01
Full Text Available We present the current status on the possible bound states of extra generation quarks. These include phenomenology and search strategy at the LHC. If chiral fourth-generation quarks do exist their strong Yukawa couplings, implied by current experimental lower bound on their masses, may lead to formation of bound states. Due to nearly degenerate 4G masses suggested by Precision Electroweak Test one can employ “heavy isospin” symmetry to classify possible spectrum. Among these states, the color-octet isosinglet vector ω 8 is the easiest to be produced at the LHC. The discovery potential and corresponding decay channels are covered in this paper. With possible light Higgs at ~125 GeV two-Higgs doublet version is briefly discussed.
Creed, Peter A.; Patton, Wendy; Hood, Michelle
2010-01-01
We surveyed 506 Australian high school students on career development (exploration, planning, job-knowledge, decision-making, indecision), personal functioning (well-being, self-esteem, life satisfaction, school satisfaction) and control variables (parent education, school achievement), and tested differences among work-bound, college-bound and…
Causality, joint measurement and Tsirelson's bound
International Nuclear Information System (INIS)
Choudhary, Sujit K.; Kar, Guruprasad; Kunkri, Samir; Rahaman, Ramij
2007-01-01
Tsirelson showed that 2√(2) is the maximum value that CHSH expression can take for quantum correlations [B.S. Tsirelson, Lett. Math. Phys. 4 (1980) 93]. This bound simply follows from the algebra of observables. Recently by exploiting the physical structure of quantum mechanics like unitarity and linearity, Buhrman and Massar [H. Buhrman, S. Massar, Phys. Rev. A 72 (2005) 052103] have established that violation of Tsirelson's bound in quantum mechanics will imply signalling. We prove the same with the help of realistic joint measurement in quantum mechanics and a Bell's inequality which has been derived under the assumption of existence of joint measurement and no signalling condition
G-frames with bounded linear operators
Xiao, Xiang-chun; Zhu, Yu-can; Shu, Zhi-biao; Ding, Ming-ling
2015-01-01
In this paper, we introduce the more general g-frame which is called a $K$-g-frame by combining a g-frame with a bounded linear operator $K$ in a Hilbert space. We give several equivalent characterizations for $K$-g-frames and discuss the stability of perturbation for $K$-g-frames. We also investigate the relationship between a $K$-g-frame and the range of the bounded linear operator $K$. In the end, we give two sufficient conditions for the remainder of a $K$-g-frame after an erasure to stil...
Quantum Kolmogorov complexity and bounded quantum memory
Miyadera, Takayuki
2011-04-01
The effect of bounded quantum memory in a primitive information protocol has been examined using the quantum Kolmogorov complexity as a measure of information. We employed a toy two-party protocol in which Bob, by using a bounded quantum memory and an unbounded classical memory, estimates a message that was encoded in qubits by Alice in one of the bases X or Z. Our theorem gave a nontrivial effect of the memory boundedness. In addition, a generalization of the uncertainty principle in the presence of quantum memory has been obtained.
Quantum Kolmogorov complexity and bounded quantum memory
International Nuclear Information System (INIS)
Miyadera, Takayuki
2011-01-01
The effect of bounded quantum memory in a primitive information protocol has been examined using the quantum Kolmogorov complexity as a measure of information. We employed a toy two-party protocol in which Bob, by using a bounded quantum memory and an unbounded classical memory, estimates a message that was encoded in qubits by Alice in one of the bases X or Z. Our theorem gave a nontrivial effect of the memory boundedness. In addition, a generalization of the uncertainty principle in the presence of quantum memory has been obtained.
Learning within bounds and dream sleep
Geszti, T.; Pazmandi, F.
1987-12-01
In a bounded-synapses version of Hopfield's model (1984) for neural networks the quasienergy of a given memory, which is approximately equal to the depth of the corresponding energy well is calculated exactly by treating the change of a synaptic strength on learning as a random walk within bounds. Attractors corresponding to stored memories are found to be considerably flattened before serious retrieval errors arise. This allows dream sleep to be interpreted as random recall and relearning of fresh strong memories, in order to stack them on top of weak incidental memory imprints of a day.
Quantum Kolmogorov Complexity and Bounded Quantum Memory
Miyadera, Takayuki
2011-01-01
In this study, the effect of bounded quantum memory in a primitive information protocol has been examined using the quantum Kolmogorov complexity as a measure of information. We employed a toy two-party protocol in which Bob by using a bounded quantum memory and an unbounded classical memory estimates a message that was encoded in qubits by Alice in one of the bases X or Z. Our theorem gave a nontrivial effect of the memory boundedness. In addition, a generalization of the uncertainty princip...
Violation of Energy Bounds in Designer Gravity
Hertog, T
2007-01-01
We continue our study of the stability of designer gravity theories, where one considers anti-de Sitter gravity coupled to certain tachyonic scalars with boundary conditions defined by a smooth function W. It has recently been argued there is a lower bound on the conserved energy in terms of the global minimum of W, if the scalar potential arises from a superpotential P and the scalar reaches an extremum of P at infinity. We show, however, there are superpotentials for which these bounds do not hold.
Bound states in curved quantum waveguides
International Nuclear Information System (INIS)
Exner, P.; Seba, P.
1987-01-01
We study free quantum particle living on a curved planar strip Ω of a fixed width d with Dirichlet boundary conditions. It can serve as a model for electrons in thin films on a cylindrical-type substrate, or in a curved quantum wire. Assuming that the boundary of Ω is infinitely smooth and its curvature decays fast enough at infinity, we prove that a bound state with energy below the first transversal mode exists for all sufficiently small d. A lower bound on the critical width is obtained using the Birman-Schwinger technique. (orig.)
Finding Maximal Pairs with Bounded Gap
DEFF Research Database (Denmark)
Brodal, Gerth Stølting; Lyngsø, Rune B.; Pedersen, Christian N. S.
1999-01-01
. In this paper we present methods for finding all maximal pairs under various constraints on the gap. In a string of length n we can find all maximal pairs with gap in an upper and lower bounded interval in time O(n log n+z) where z is the number of reported pairs. If the upper bound is removed the time reduces...... to O(n+z). Since a tandem repeat is a pair where the gap is zero, our methods can be seen as a generalization of finding tandem repeats. The running time of our methods equals the running time of well known methods for finding tandem repeats....
Hybridization thermodynamics of DNA bound to gold nanoparticles
International Nuclear Information System (INIS)
Lang, Brian
2010-01-01
Isothermal Titration Calorimetry (ITC) was used to study the thermodynamics of hybridization on DNA-functionalized colloidal gold nanoparticles. When compared to the thermodynamics of hybridization of DNA that is free in solution, the differences in the values of the Gibbs free energy of reaction, Δ r G o , the enthalpy, Δ r H o , and entropy, Δ r S o , were small. The change in Δ r G o between the free and bound states was always positive but with statistical significance outside the 95% confidence interval, implying the free DNA is slightly more stable than when in the bound state. Additionally, ITC was also able to reveal information about the binding stoichiometry of the hybridization reactions on the DNA-functionalized gold nanoparticles, and indicates that there is a significant fraction of the DNA on gold nanoparticle surface that is unavailable for DNA hybridization. Furthermore, the fraction of available DNA is dependent on the spacer group on the DNA that is used to span the gold surface from that to the probe DNA.
Scattering theory methods for bound state problems
International Nuclear Information System (INIS)
Raphael, R.B.; Tobocman, W.
1978-01-01
For the analysis of the properties of a bound state system one may use in place of the Schroedinger equation the Lippmann-Schwinger (LS) equation for the wave function or the LS equation for the reactance operator. Use of the LS equation for the reactance operator constrains the solution to have correct asymptotic behaviour, so this approach would appear to be desirable when the bound state wave function is to be used to calculate particle transfer form factors. The Schroedinger equation based N-level analysis of the s-wave bound states of a square well is compared to the ones based on the LS equation. It is found that the LS equation methods work better than the Schroedinger equation method. The method that uses the LS equation for the wave function gives the best results for the wave functions while the method that uses the LS equation for the reactance operator gives the best results for the binding energies. The accuracy of the reactance operator based method is remarkably insensitive to changes in the oscillator constant used for the harmonic oscillator function basis set. It is also remarkably insensitive to the number of nodes in the bound state wave function. (Auth.)
Computational Lower Bounds Using Diagonalization-II
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 4. Computational Lower Bounds Using Diagonalization - II. M V Panduranga Rao. General Article Volume 15 Issue 4 April 2010 pp 337-346 ... Keywords. Diagonalization; time–hierarchy theorem; relativization; Baker–Gill–Solovay theorem.
Bounds on Gromov hyperbolicity constant in graphs
Indian Academy of Sciences (India)
Home; Journals; Proceedings – Mathematical Sciences; Volume 122; Issue 1. Bounds on Gromov Hyperbolicity Constant in Graphs. José M Rodríguez José M Sigarreta. Volume 122 ... Spain; Facultad de Matemáticas, Universidad Autónoma de Guerrero, Carlos E. Adame No. 54 Col. Garita, 39650 Acalpulco Gro., Mexico ...
Bogomol'nyi bounds for cosmic strings
International Nuclear Information System (INIS)
Comtet, A.; Gibbons, G.W.; Cambridge Univ.
1987-09-01
We establish Bogomol'nyi inequalities for the deficit angle of some cylindrically symmetric asymptotically local flat (CALF) spacetimes containing cosmic strings. These results prove the stability against arbitrary cylindrical deformations of those configurations which saturate the bound. Such configurations satisfy first order equations which can, in some cases, be solved exactly
Bounded Rationality of Generalized Abstract Fuzzy Economies
Directory of Open Access Journals (Sweden)
Lei Wang
2014-01-01
Full Text Available By using a nonlinear scalarization technique, the bounded rationality model M for generalized abstract fuzzy economies in finite continuous spaces is established. Furthermore, by using the model M, some new theorems for structural stability and robustness to (λ,ϵ-equilibria of generalized abstract fuzzy economies are proved.
Theoretical Bounds of Direct Binary Search Halftoning.
Liao, Jan-Ray
2015-11-01
Direct binary search (DBS) produces the images of the best quality among half-toning algorithms. The reason is that it minimizes the total squared perceived error instead of using heuristic approaches. The search for the optimal solution involves two operations: (1) toggle and (2) swap. Both operations try to find the binary states for each pixel to minimize the total squared perceived error. This error energy minimization leads to a conjecture that the absolute value of the filtered error after DBS converges is bounded by half of the peak value of the autocorrelation filter. However, a proof of the bound's existence has not yet been found. In this paper, we present a proof that shows the bound existed as conjectured under the condition that at least one swap occurs after toggle converges. The theoretical analysis also indicates that a swap with a pixel further away from the center of the autocorrelation filter results in a tighter bound. Therefore, we propose a new DBS algorithm which considers toggle and swap separately, and the swap operations are considered in the order from the edge to the center of the filter. Experimental results show that the new algorithm is more efficient than the previous algorithm and can produce half-toned images of the same quality as the previous algorithm.
Monotonicity and bounds on Bessel functions
Directory of Open Access Journals (Sweden)
Larry Landau
2000-07-01
Full Text Available survey my recent results on monotonicity with respect to order of general Bessel functions, which follow from a new identity and lead to best possible uniform bounds. Application may be made to the "spreading of the wave packet" for a free quantum particle on a lattice and to estimates for perturbative expansions.
Threshold Circuit Lower Bounds on Cryptographic Functions
E. Kiltz (Eike); H.U. Simon
2005-01-01
textabstractIn this work, we are interested in non-trivial upper bounds on the spectral norm of binary matrices $M$ from {-1, 1} $^{N × N}$. It is known that the distributed Boolean function represented by $M$ is hard to compute in various restricted models of computation if the spectral norm is
O{sup -} bound small polarons in oxide materials
Energy Technology Data Exchange (ETDEWEB)
Schirmer, O F [Department of Physics, University of Osnabrueck, D-49076 Osnabrueck (Germany)
2006-11-01
Holes bound to acceptor defects in oxide crystals are often localized by lattice distortion at just one of the equivalent oxygen ligands of the defect. Such holes thus form small polarons in symmetric clusters of a few oxygen ions. An overview on mainly the optical manifestations of those clusters is given. The article is essentially divided into two parts: the first one covers the basic features of the phenomena and their explanations, exemplified by several paradigmatic defects; in the second part numerous oxide materials are presented which exhibit bound small polaron optical properties. The first part starts with summaries on the production of bound hole polarons and the identification of their structure. It is demonstrated why they show strong, wide absorption bands, usually visible, based on polaron stabilization energies of typically 1 eV. The basic absorption process is detailed with a fictitious two-well system. Clusters with four, six and twelve equivalent ions are realized in various oxide compounds. In these cases several degenerate optically excited polaron states occur, leading to characteristic final state resonance splittings. The peak energies of the absorption bands as well as the sign of the transfer energy depend on the topology of the clusters. A special section is devoted to the distinction between interpolaron and intrapolaron optical transitions. The latter are usually comparatively weak. The oxide compounds exhibiting bound hole small polaron absorptions include the alkaline earth oxides (e.g. MgO), BeO and ZnO, the perovskites BaTiO{sub 3} and KTaO{sub 3}, quartz, the sillenites (e.g. Bi{sub 12}TiO{sub 20}), Al{sub 2}O{sub 3}, LiNbO{sub 3}, topaz and various other materials. There are indications that the magnetic crystals NiO, doped with Li, and LaMnO{sub 3}, doped with Sr, also show optical features caused by bound hole polarons. Beyond being elementary paradigms for the properties of small polarons in general, the defect species treated
The quality of zero bounds for complex polynomials.
Dehmer, Matthias; Tsoy, Yury Robertovich
2012-01-01
In this paper, we evaluate the quality of zero bounds on the moduli of univariate complex polynomials. We select classical and recently developed bounds and evaluate their quality by using several sets of complex polynomials. As the quality of priori bounds has not been investigated thoroughly, our results can be useful to find optimal bounds to locate the zeros of complex polynomials.
Bounds on fluid permeability for viscous flow through porous media
International Nuclear Information System (INIS)
Berryman, J.G.
1985-01-01
General properties of variational bounds on Darcy's constant for slow viscous flow through porous media are studied. The bounds are also evaluated numerically for the penetrable sphere model. The bound of Doi depending on two-point correlations and the analytical bound of Weissberg and Prager give comparable results in the low density limit but the analytical bound is superior for higher densities. Prager's bound depending on three-point correlation functions is worse than the analytical bound at low densities but better (although comparable to it) at high densities. A procedure for methodically improving Prager's three point bound is presented. By introducing a Gaussian trial function, the three-point bound is improved by an order of magnitude for moderate values of porosity. The new bounds are comparable in magnitude to the Kozeny--Carman empirical relation for porous materials
Bounded rational choice behaviour: applications in transport
DEFF Research Database (Denmark)
Jensen, Anders Fjendbo
2016-01-01
Even though the theory of rational behaviour has been challenged for almost 100 years, the dominant approach within the field of transport has been based upon the assumptions of neoclassical economics that we live in a world of rational decision makers who always have perfect knowledge and aim to...... and limited processing may occur due to time constraints, low involvement in the decision at hand, relying on habits or the task requiring too high a mental effort....... to maximise some subjective measure. Where other fields, for example within the social sciences and psychology, have made serious efforts to explore alternative models derived from principles of bounded rationality, this direction has begun to take speed within transport applications only recently. Bounded...
Entropic bounds between two thermal equilibrium states
López-Saldívar, Julio A.; Castaños, Octavio; Man'ko, Margarita A.; Man'ko, Vladimir I.
2018-02-01
The positivity conditions of the relative entropy between two thermal equilibrium states ρ̂1 and ρ̂2 are used to obtain upper and lower bounds for the subtraction of their entropies, the Helmholtz potential and the Gibbs potential of the two systems. These limits are expressed in terms of the mean values of the Hamiltonians, number operator, and temperature of the different systems. In particular, we discuss these limits for molecules that can be represented in terms of the Franck-Condon coefficients. We emphasize the case where the Hamiltonians belong to the same system at two different times t and t'. Finally, these bounds are obtained for a general qubit system and for the harmonic oscillator with a time-dependent frequency at two different times.
Asymptotic Sharpness of Bounds on Hypertrees
Directory of Open Access Journals (Sweden)
Lin Yi
2017-08-01
Full Text Available The hypertree can be defined in many different ways. Katona and Szabó introduced a new, natural definition of hypertrees in uniform hypergraphs and investigated bounds on the number of edges of the hypertrees. They showed that a k-uniform hypertree on n vertices has at most (nk−1$\\left( {\\matrix{n \\cr {k - 1} } } \\right$ edges and they conjectured that the upper bound is asymptotically sharp. Recently, Szabó verified that the conjecture holds by recursively constructing an infinite sequence of k-uniform hypertrees and making complicated analyses for it. In this note we give a short proof of the conjecture by directly constructing a sequence of k-uniform k-hypertrees.
Nemytskii operator on generalized bounded variation space
Directory of Open Access Journals (Sweden)
René Erlín Castillo
2014-06-01
Full Text Available In this paper we show that if the Nemytskii operator maps the (φ, α-bounded variation space into itself and satisfies some Lipschitz condition, then there are two functions g and h belonging to the (φ, α-bounded variation space such that f(t, y = g(ty + h(t for all t ∈ [a, b], y ∈ R. Resumen. En este artículo demostramos que si el operador de Nemytskii lleva el espacio de variación (φ, α-acotada en sí mismo, y satisface cierta condición de Lipschitz, entonces existen dos funciones g y h perteneciendo al espacio de variación (φ, α-acotada tal que f(t, y = g(ty + h(t para todo t ∈ [a, b], y ∈ R.
Spectral singularities and zero energy bound states
Energy Technology Data Exchange (ETDEWEB)
Heiss, W.D. [National Institute for Theoretical Physics, Stellenbosch Institute for Advanced Study, and Institute of Theoretical Physics, University of Stellenbosch, 7602 Matieland (South Africa); Nazmitdinov, R.G. [Department de Fisica, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)
2011-08-15
Single particle scattering around zero energy is re-analysed in view of recent experiments with ultra-cold atoms, nano-structures and nuclei far from the stability valley. For non-zero orbital angular momentum the low energy scattering cross section exhibits dramatic changes depending on the occurrence of either a near resonance or a bound state or the situation in between, that is a bound state at zero energy. Such state is singular in that it has an infinite scattering length, behaves for the eigenvalues but not for the eigenfunctions as an exceptional point and has no pole in the scattering function. These results should be observable whenever the interaction or scattering length can be controlled. (authors)
Optimal Bounds in Parametric LTL Games
Directory of Open Access Journals (Sweden)
Martin Zimmermann
2011-06-01
Full Text Available We consider graph games of infinite duration with winning conditions in parameterized linear temporal logic, where the temporal operators are equipped with variables for time bounds. In model checking such specifications were introduced as "PLTL" by Alur et al. and (in a different version called "PROMPT-LTL" by Kupferman et al.. We present an algorithm to determine optimal variable valuations that allow a player to win a game. Furthermore, we show how to determine whether a player wins a game with respect to some, infinitely many, or all valuations. All our algorithms run in doubly-exponential time; so, adding bounded temporal operators does not increase the complexity compared to solving plain LTL games.
Optima and bounds for irreversible thermodynamic processes
International Nuclear Information System (INIS)
Hoffmann, K.H.
1990-01-01
In this paper bounds and optima for irreversible thermodynamic processes and their application in different fields are discussed. The tools of finite time thermodynamics are presented and especially optimal control theory is introduced. These methods are applied to heat engines, including models of the Diesel engine and a light-driven engine. Further bounds for irreversible processes are introduced, discussing work deficiency and its relation to thermodynamic length. Moreover the problem of dissipation in systems composed of several subsystems is studied. Finally, the methods of finite time thermodynamics are applied to thermodynamic processes described on a more microscopic level. The process used as an example is simulated annealing. It is shown how optimal control theory is applied to find the optimal cooling schedule for this important stochastic optimization method
A holographic bound for D3-brane
Energy Technology Data Exchange (ETDEWEB)
Momeni, Davood; Myrzakul, Aizhan; Myrzakulov, Ratbay [Eurasian National University, Eurasian International Center for Theoretical Physics, Astana (Kazakhstan); Eurasian National University, Department of General Theoretical Physics, Astana (Kazakhstan); Faizal, Mir [University of British Columbia-Okanagan, Irving K. Barber School of Arts and Sciences, Kelowna, BC (Canada); University of Lethbridge, Department of Physics and Astronomy, Lethbridge, AB (Canada); Bahamonde, Sebastian [University College London, Department of Mathematics, London (United Kingdom)
2017-06-15
In this paper, we will regularize the holographic entanglement entropy, holographic complexity and fidelity susceptibility for a configuration of D3-branes. We will also study the regularization of the holographic complexity from the action for a configuration of D3-branes. It will be demonstrated that for a spherical shell of D3-branes the regularized holographic complexity is always greater than or equal to the regularized fidelity susceptibility. Furthermore, we will also demonstrate that the regularized holographic complexity is related to the regularized holographic entanglement entropy for this system. Thus, we will obtain a holographic bound involving regularized holographic complexity, regularized holographic entanglement entropy and regularized fidelity susceptibility of a configuration of D3-brane. We will also discuss a bound for regularized holographic complexity from action, for a D3-brane configuration. (orig.)
Entanglement detection with bounded reference frames
International Nuclear Information System (INIS)
Costa, Fabio; Brukner, Caslav; Harrigan, Nicholas; Rudolph, Terry
2009-01-01
Quantum experiments usually assume the existence of perfect, classical reference frames (RFs), which allow for the specification of measurement settings (e.g. orientation of the Stern-Gerlach magnet in spin measurements) with arbitrary precision. If the RFs are 'bounded' (i.e. quantum systems themselves, having a finite number of degrees of freedom), only limited precision can be attained. Using spin coherent states as bounded RFs, we have found the minimum size needed for them to violate local realism for entangled spin systems. For composite systems of spin 1/2 particles, RFs of very small size are sufficient for the violation; however, to see this violation for macroscopic entangled spins, the size of the RF must be at least quadratically larger than that of the spins. The unavailability of such RFs gives a possible explanation for the non-observance of violation of local realism in everyday experience.
Bounding probabilistic safety assessment probabilities by reality
International Nuclear Information System (INIS)
Fragola, J.R.; Shooman, M.L.
1991-01-01
The investigation of the failure in systems where failure is a rare event makes the continual comparisons between the developed probabilities and empirical evidence difficult. The comparison of the predictions of rare event risk assessments with historical reality is essential to prevent probabilistic safety assessment (PSA) predictions from drifting into fantasy. One approach to performing such comparisons is to search out and assign probabilities to natural events which, while extremely rare, have a basis in the history of natural phenomena or human activities. For example the Segovian aqueduct and some of the Roman fortresses in Spain have existed for several millennia and in many cases show no physical signs of earthquake damage. This evidence could be used to bound the probability of earthquakes above a certain magnitude to less than 10 -3 per year. On the other hand, there is evidence that some repetitive actions can be performed with extremely low historical probabilities when operators are properly trained and motivated, and sufficient warning indicators are provided. The point is not that low probability estimates are impossible, but continual reassessment of the analysis assumptions, and a bounding of the analysis predictions by historical reality. This paper reviews the probabilistic predictions of PSA in this light, attempts to develop, in a general way, the limits which can be historically established and the consequent bounds that these limits place upon the predictions, and illustrates the methodology used in computing such limits. Further, the paper discusses the use of empirical evidence and the requirement for disciplined systematic approaches within the bounds of reality and the associated impact on PSA probabilistic estimates
Maximum Bounded Rooted-Tree Packing Problem
Kerivin, Herve; Leblet, Jimmy; Simon, Gwendal; Zhou, Fen
2011-01-01
Given a graph and a root, the Maximum Bounded Rooted-Tree Packing (MBRTP) problem aims at finding K rooted-trees that span the largest subset of vertices, when each vertex has a limited outdegree. This problem is motivated by peer-to-peer streaming overlays in under-provisioned systems. We prove that the MBRTP problem is NP-complete. We present two polynomial-time algorithms that computes an optimal solution on complete graphs and trees respectively.
Closed form bound-state perturbation theory
Directory of Open Access Journals (Sweden)
Ollie J. Rose
1980-01-01
Full Text Available The perturbed Schrödinger eigenvalue problem for bound states is cast into integral form using Green's Functions. A systematic algorithm is developed and applied to the resulting equation giving rise to approximate solutions expressed as functions of the given perturbation parameter. As a by-product, convergence radii for the traditional Rayleigh-Schrödinger and Brillouin-Wigner perturbation theories emerge in a natural way.
Multipartite secret key distillation and bound entanglement
International Nuclear Information System (INIS)
Augusiak, Remigiusz; Horodecki, Pawel
2009-01-01
Recently it has been shown that quantum cryptography beyond pure entanglement distillation is possible and a paradigm for the associated protocols has been established. Here we systematically generalize the whole paradigm to the multipartite scenario. We provide constructions of new classes of multipartite bound entangled states, i.e., those with underlying twisted Greenberger-Horne-Zeilinger (GHZ) structure and nonzero distillable cryptographic key. We quantitatively estimate the key from below with the help of the privacy squeezing technique.
Exact BPS bound for noncommutative baby Skyrmions
Energy Technology Data Exchange (ETDEWEB)
Domrin, Andrei, E-mail: domrin@mi.ras.ru [Department of Mathematics and Mechanics, Moscow State University, Leninskie gory, 119992, GSP-2, Moscow (Russian Federation); Lechtenfeld, Olaf, E-mail: lechtenf@itp.uni-hannover.de [Institut für Theoretische Physik and Riemann Center for Geometry and Physics, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover (Germany); Linares, Román, E-mail: lirr@xanum.uam.mx [Departamento de Física, Universidad Autónoma Metropolitana Iztapalapa, San Rafael Atlixco 186, C.P. 09340, México D.F. (Mexico); Maceda, Marco, E-mail: mmac@xanum.uam.mx [Departamento de Física, Universidad Autónoma Metropolitana Iztapalapa, San Rafael Atlixco 186, C.P. 09340, México D.F. (Mexico)
2013-11-25
The noncommutative baby Skyrme model is a Moyal deformation of the two-dimensional sigma model plus a Skyrme term, with a group-valued or Grassmannian target. Exact abelian solitonic solutions have been identified analytically in this model, with a singular commutative limit. Inside any given Grassmannian, we establish a BPS bound for the energy functional, which is saturated by these baby Skyrmions. This asserts their stability for unit charge, as we also test in second-order perturbation theory.
Isoperimetric upper bounds for the first eigenvalue
Indian Academy of Sciences (India)
eigenvalue of M was given in terms of the integral of the first eigenvalue of the geodesic spheres centred at the centre of gravity of M. For precious statements, see [10]. In this paper, we obtain isoperimetric upper bounds for the first eigenvalue λ1(M) of a hypersurface M in M(κ). We refer to [2] and [8] for the basic Riemannian ...
New approach to calculate bound state eigenvalues
International Nuclear Information System (INIS)
Gerck, E.; Gallas, J.A.C.
1983-01-01
A method of solving the radial Schrodinger equation for bound states is discussed. The method is based on a new piecewise representation of the second derivative operator on a set of functions that obey the boundary conditions. This representation is trivially diagonalised and leads to closed form expressions of the type E sub(n)=E(ab+b+c/n+...) for the eigenvalues. Examples are given for the power-law and logarithmic potentials. (Author) [pt
Bounds on scalar leptoquarks from Z physics
Mizukoshi, J K; González-Garciá, M Concepción; Mizukoshi, J K; Eboli, O J P; Gonzalez-Garcia, M C
1995-01-01
We analyse the constraints on scalar leptoquarks coming from radiative corrections to Z physics. We perform a global fitting to the LEP data including the contributions of the most general effective Lagrangian for scalar leptoquarks, which exhibits the SU(2)_L \\times U(1)_Y gauge invariance. We show that the bounds on leptoquarks that couple to the top quark are much stronger than the ones obtained from low energy experiments.
Recent advances in bound state quantum electrodynamics
International Nuclear Information System (INIS)
Brodsky, S.J.; Lepage, G.P.
1977-06-01
Recent developments are reviewed in four areas of computational quantum electrodynamics: a new relativistic two-body formalism equal in rigor to the Bethe-Salpeter formalism but with strong calculational advantages is discussed; recent work on the computation of the decay rate of bound systems (positronium in particular) is presented; limits on possible composite structure of leptons are discussed; a new multidimensional integration program ('VEGAS') suitable for higher order calculations is presented
The organically bound tritium: an analyst vision
International Nuclear Information System (INIS)
Ansoborlo, E.; Baglan, N.
2009-01-01
The authors report the work of a work group on tritium analysis. They recall the different physical forms of tritium: gas (HT, hydrogen-tritium), water vapour (HTO or tritiated water) or methane (CH3T), but also in organic compounds (OBT, organically bound tritium) which are either exchangeable or non-exchangeable. They evoke measurement techniques and methods, notably to determine the tritium volume activity. They discuss the possibilities to analyse and distinguish exchangeable and non-exchangeable OBTs
A sorting network in bounded arithmetic
Czech Academy of Sciences Publication Activity Database
Jeřábek, Emil
2011-01-01
Roč. 162, č. 4 (2011), s. 341-355 ISSN 0168-0072 R&D Projects: GA AV ČR IAA1019401; GA MŠk(CZ) 1M0545 Institutional research plan: CEZ:AV0Z10190503 Keywords : bounded arithmetic * sorting network * proof complexity * monotone sequent calculus Subject RIV: BA - General Mathematics Impact factor: 0.450, year: 2011 http://www.sciencedirect.com/science/article/pii/S0168007210001272
EXPLICIT LOWER BOUNDS FOR LINEAR FORMS
DEFF Research Database (Denmark)
Leppälä, Kalle
2016-01-01
Let I be the field of rational numbers or an imaginary quadratic field and Z(I) its ring of integers. We study some general lemmas that produce lower bounds vertical bar B-0 + B-1 theta(1) +... + B-r theta(r)vertical bar >= 1/max{vertical bar B-1 vertical bar,...,vertical bar B-r vertical bar}(mu...
Bounded solutions and wavefronts for discrete dynamics
Czech Academy of Sciences Publication Activity Database
Malaguti, L.; Řehák, Pavel; Taddei, V.
2004-01-01
Roč. 47, - (2004), s. 1079-1094 ISSN 0898-1221 R&D Projects: GA ČR GA201/01/0079; GA ČR GP201/01/P041 Institutional research plan: CEZ:AV0Z1019905 Keywords : nonlinear difference equation * bounded solution * discrete travelling waves Subject RIV: BA - General Mathematics Impact factor: 0.431, year: 2004
Bounded Target Cascading in Hierarchical Design Optimization
Directory of Open Access Journals (Sweden)
Xiaoling Zhang
2014-06-01
Full Text Available For large scale systems, as a hierarchical multilevel decomposed design optimization method, analytical target cascading coordinates the inconsistency between the assigned targets and response in each level by a weighted-sum formulation. To avoid the problems associated with the weighting coefficients, single objective functions in the hierarchical design optimization are formulated by a bounded target cascading method in this paper. In the BTC method, a single objective optimization problem is formulated in the system level, and two kinds of coordination constraints are added: one is bound constraint for the design points based on the response from each subsystem level and the other is linear equality constraint for the common variables based on their sensitivities with respect to each subsystem. In each subsystem level, the deviation with target for design point is minimized in the objective function, and the common variables are constrained by target bounds. Therefore, in the BTC method, the targets are coordinated based on the optimization iteration information in the hierarchical design problem and the performance of the subsystems, and BTC method will converge to the global optimum efficiently. Finally, comparisons of the results from BTC method and the weighted-sum analytical target cascading method are presented and discussed.
Heterotrophic free-living and particle-bound bacterial cell size in the ...
Indian Academy of Sciences (India)
Regression analysis revealed that 18% of the variation in mean heterotrophic free-living bacterial cell size was due to biological oxygen demand (BOD) in the river Arkavathy, 11% due to surface water velocity (SWV) in the river Cauvery and 11% due to temperature in the river Kapila. Heterotrophic particle-bound bacterial ...
Relative bioavailability of soil-bound chlordecone in growing lambs.
Jurjanz, S; Jondreville, C; Mahieu, M; Fournier, A; Archimède, H; Rychen, G; Feidt, C
2014-10-01
The pollution of soil with the pesticide chlordecone (CLD) is a problem for the use of agricultural surfaces even years after its use has been forbidden. Therefore, the exposure of free-ranged animals such as ruminants needs to be investigated in order to assess the risk of contamination of the food chain. Indeed, measured concentrations could be integrated in a lowered extent if the soil binding would reduce the bioavailability of the pesticide. This bioavailability of soil-bound CLD in a heavily polluted andosol has been investigated relatively of CLD given via spiked oil. Twenty-four weaned lambs were exposed to graded doses of 2, 4 or 6 μg CLD/kg body weight during 15 days via the contaminated soil in comparison to spiked oil. The concentration of this pesticide has been determined in two target tissues: blood serum and kidney fat. The relative bioavailability (RBA) corresponds to the slope ratio between the test matrix-contaminated soil- in comparison to the reference matrix oil. The RBA of the soil-bound CLD was not found to significantly differ from the reference matrix oil in lambs meaning that the pesticide ingested by grazing ruminants would not be sequestered by soil binding. Therefore, CLD from soil gets bioavailable within the intestinal level and exposure to contaminated soil has to be integrated in risk assessments.
On the Feng-Rao bound for generalized hamming weights
DEFF Research Database (Denmark)
Geil, Hans Olav; Thommesen, Christian
2006-01-01
The Feng-Rao bound gives good estimates of the minimum distance of a large class of codes. In this work we are concerned with the problem of how to extend the Feng-Rao bound so that it deals with all the generalized Hamming weights. The problem was solved by Heijnen and Pellikaan in [7] for a large...... establish the connection to the Shibuya-Sakaniwa bound for generalized Hamming weights ([15], [16], [17], [18], [19] and [20]). More precisely we show that the Shibuya-Sakaniwa bound is a consequence of the extended Feng-Rao bound. In particular the extended Feng-Rao bound gives always at least as good...
On the Feng-Rao bound for generalized Hamming weights
DEFF Research Database (Denmark)
Geil, Olav; Thommesen, Christian
2005-01-01
The Feng-Rao bound gives good estimates of the minimum distance of a large class of codes. In this work we are concerned with the problem of how to extend the Feng-Rao bound so that it deals with all the generalized Hamming weights. The problem was solved by Heijnen and Pellikaan in [7] for a large...... establish the connection to the Shibuya-Sakaniwa bound for generalized Hamming weights ([15], [16], [17], [18], [19] and [20]). More precisely we show that the Shibuya-Sakaniwa bound is a consequence of the extended Feng-Rao bound. In particular the extended Feng-Rao bound gives always at least as good...
Automatically controlled correlation spectrometer with a bounded positron beam
International Nuclear Information System (INIS)
Grone, R.
1991-01-01
The spectrometer consists of a frame which carries a fixed arm with collimating slits and a pair of scintillator units positioned against each other, and a movable arm which moves in the horizontal plane and also holds collimating slits and two scintillator units positioned against each other. In the centre of the frame is a shielding cover with a chamber housing a slidable positron source. The end of the cover is fitted with a replaceable diaphragm against which a sample holder is positioned. The chamber with a bounded positron beam can be employed to measure a sample at preselected sites and thus gain information concerning various parts of the sample surface and its inhomogeneity. (M.D.). 3 figs
The S-matrix for systems with bound states
Ruijgrok, Th.W.
A unitary S-matrix is defined for a system of three particles, two of which can form a bound state. It is shown how for elastic scattering the polarization of the bound state must be taken into account.
Bound values for Hall conductivity of heterogeneous medium under ...
Indian Academy of Sciences (India)
- ditions in inhomogeneous medium has been studied. It is shown that bound values for. Hall conductivity differ from bound values for metallic conductivity. This is due to the unusual character of current percolation under quantum Hall effect ...
The bound fraction of young star clusters
Brinkmann, Nina; Banerjee, Sambaran; Motwani, Bhawna; Kroupa, Pavel
2017-04-01
Context. The residual gas within newly formed star clusters is expelled through stellar feedback on timescales ≲ 1 Myr. The subsequent expansion of the cluster results in an unbinding of a fraction of stars, before the remaining cluster members can re-virialize and form a surviving cluster. Aims: We investigate the bound fraction after gas expulsion as a function of initial cluster mass in stars Mecl and gauge the influence of primordial mass segregation, stellar evolution and the tidal field at solar distance. We also assess the impact of the star-formation efficiency ɛSFE and gas expulsion velocity vg. Methods: We perform N-body simulations using Sverre Aarseth's NBODY7 code, starting with compact clusters in their embedded phase and approximate the gas expulsion by means of an exponentially depleting external gravitational field. We follow the process of re-virialization through detailed monitoring of different Lagrange radii over several Myr, examining initial half-mass radii of 0.1 pc, 0.3 pc and 0.5 pc and Mecl usually ranging from 5 × 103M⊙ to 5 × 104M⊙. Results: The strong impact of the relation between the gas expulsion timescale and the crossing time means that clusters with the same initial core density can have very different bound fractions. The adopted ɛSFE = 0.33 in the cluster volume results in a distinct sensitivity to vg over a wide mass range, while a variation of ɛSFE can make the cluster robust to the rapidly decreasing external potential. We confirm that primordial mass segregation leads to a smaller bound fraction, its influence possibly decreasing with mass. Stellar evolution has a higher impact on lower mass clusters, but heating through dynamical friction could expand the cluster to a similar extent. The examined clusters expand well within their tidal radii and would survive gas expulsion even in a strong tidal field.
Ionically Bound Peroxidase from Peach Fruit
Directory of Open Access Journals (Sweden)
Neves Valdir Augusto
2002-01-01
Full Text Available Soluble, ionically bound peroxidase (POD and polyphenoloxidase (PPO were extracted from the pulp of peach fruit during ripening at 20°C. Ionically bound form was purified 6.1-fold by DEAE-cellulose and Sephadex G-100 chromatography. The purified enzyme showed only one peak of activity on Sephadex G-100 and PAGE revealed that the enzyme was purified by the procedures adopted. The purified enzyme showed a molecular weight of 29000 Da, maximum activity at pH 5.0 and at 40ºC. The calculated apparent activation energy (Ea for the reaction was10.04 kcal/mol. The enzyme was heat-labile in the temperature range of 60 to 75ºC with a fast inactivation at 75ºC. Measurement of residual activity showed a stabilizing effect of sucrose at various temperature/sugar concentrations (0, 10, 20 %, w/w, with an activation energy (Ea for inactivation increasing with sucrose concentration from 0 to 20% (w/w. The Km and Vmax values were 9.35 and 15.38 mM for 0-dianisidine and H2O2, respectively. The bound enzyme was inhibited competitively by ferulic, caffeic and protocatechuic acids with different values of Ki,. L-cysteine, p-coumaric and indolacetic acid and Fe++ also inhibited the enzyme but at a lower grade. N-ethylmaleimide and p-CMB were not effective to inhibit the enzyme demonstrating the non-essentiality of SH groups.
Bounds on dissipation in stress-driven flow in a rotating frame
Tang, W.; Caulfield, C. P.; Young, W. R.
2005-09-01
We calculate a rigorous dual bound on the long-time-averaged mechanical energy dissipation rate varepsilon within a channel of an incompressible viscous fluid of constant kinematic viscosity nu, depth h and rotation rate f, driven by a constant surface stress {bmtau} {=} rho u(2_starxvec) , where u_star is the friction velocity. It is well known that varepsilon {≤} varepsilon_Stokes {=} u(4_star/nu) , i.e. the dissipation is bounded above by the dissipation associated with the Stokes flow.
Bound states in a strong magnetic field
International Nuclear Information System (INIS)
Machado, C. S.; Navarra, F. S.; Noronha, J.; Oliveira, E. G.; Ferreira Filho, L. G.
2013-01-01
We expect a strong magnetic field to be produced in the perpendicular direction to the reaction plane, in a noncentral heavy-ion collision . The strength of the magnetic field is estimated to be eB∼m 2 π ∼ 0.02 GeV 2 at the RHIC and eB∼ 15m 2 π ∼ 0.3 GeV 2 at the LHC. We investigate the effects of the magnetic field on B 0 and D 0 mesons, focusing on the changes of the energy levels and of the mass of the bound states.
BOUND PERIODICAL HOLDINGS BATTELLE - NORTHWEST LIBRARY
Energy Technology Data Exchange (ETDEWEB)
None
1967-05-01
This report lists the bound periodicals in the Technical Library at the Pacific Northwest Laboratory, operated by Battelle Memorial Institute. It was prepared from a computer program and is arranged in two parts. Part one is an alphabetical list of journals by title; part two is an arrangement of the journals by subject. The list headings are self-explanatory, with the exception of the title code, which is necessary in the machine processing. The listing is complete through June, 1966 and updates an earlier publication issued in March, 1965.
Andreev bound states. Some quasiclassical reflections
Energy Technology Data Exchange (ETDEWEB)
Lin, Y., E-mail: yiriolin@illinois.edu; Leggett, A. J. [University of Illinois at Urhana-Champaign, Dept. of Physics (United States)
2014-12-15
We discuss a very simple and essentially exactly solvable model problem which illustrates some nice features of Andreev bound states, namely, the trapping of a single Bogoliubov quasiparticle in a neutral s-wave BCS superfluid by a wide and shallow Zeeman trap. In the quasiclassical limit, the ground state is a doublet with a splitting which is proportional to the exponentially small amplitude for “normal” reflection by the edges of the trap. We comment briefly on a prima facie paradox concerning the continuity equation and conjecture a resolution to it.
Tracking objects with the bounded irregular pyramid
Marfil Robles, Rebeca
2006-01-01
En esta tesis se propone un sistema de seguimiento de objetos basados en un nuevo método de representación y localización del objetivo. Se trata de realizar el seguimiento de objetos no rígidos en tiempo real, sin utilizar ningún modelo previo de los objetos a seguir. Para conseguir esto, se propone un nuevo modelo para caracterizar la apariencia del objeto basado en una máscara o template. Este modelo utiliza una nueva estructura piramidal, denominada Bounded Irregular Pyramid (BIP), p...
Uniformly bounded representations of the Lorentz groups
International Nuclear Information System (INIS)
Brega, A.O.
1982-01-01
For the Lorentz group G = SO/sub e/(n + 1, 1)(ngreater than or equal to 2) the author constructs a family of uniformly bounded representations by means of analytically continuing a certain normalization of the unitary principal series. The method the author uses relies on an analysis of various operators under a Mellin transform and extends earlier work of E.N. Wilson. In a series of papers Kunze and Stein initiated the theory of uniformly bounded representations of semisimple Lie groups; the starting point is the unitary principal series T(sigma,s) obtained in a certain subgroup M of G and a purely imaginary number s. From there Kunze and Stein constructed families of representations R(sigma,s) depending analytically on a parameter s in a domain D of C containing the imaginary axis which are unitarily equilvalent to T(sigma,s) for s contained in the set of imaginary numbers and whose operator norms are uniformly bounded for each s in D. In the case of the Lorentz groups SO/sub e/(n + 1, 1)(ngreater than or equal to2) and the trivial representation 1 of M, E.N. Wilson obtained such a family R(1,s) for the domain D = [s contained in the set of C: absolute value Re(s) Vertical Bar2]. For this domain D and for any representation sigma of M the author provides a family R(sigma,s) of uniformly bounded representations analytically continuing T(sigma,s), thereby generalizing Wilson's work. The author has also investigated certain symmetry properties of the representations R(sigma,s) under the action of the Weyl group. The trivial representation is Weyl group invariant and the family R(1,s) obtained by Wilson satisfies R(1,s) = R(1,-s) reflecting this. Obtained was the analogous result R(sigma,s) = R(sigma,-s) for some well known representations sigma that are Weyl group invariant. This involves the explicit computation of certain constants arising in the Fourier transforms of intertwining operators
Bounds for the System Reliability Function.
1985-05-01
RD-RIGS 529 SOUNDS FOR THE SYSTEN RELIABILITY FUNCTION(UD RIZONm i UNIV TUCSON DEPT OF MATHENATICS J 0 SNANTHIKUNAR NAY 85 AFOSR-AS RFOSR-84-6295... compute R. Except in some special cases [e.g. Agrawal and Satyanarayana (1984), Provan and Ball (1984), and Shanthikumar (1982, 1984)], the problem...bounds get tighter as m increases and give the exact unreallbility when m - n + 1. This allows one to progressively compute A,,At+I, ... , until a desired
Score Bounded Monte-Carlo Tree Search
Cazenave, Tristan; Saffidine, Abdallah
Monte-Carlo Tree Search (MCTS) is a successful algorithm used in many state of the art game engines. We propose to improve a MCTS solver when a game has more than two outcomes. It is for example the case in games that can end in draw positions. In this case it improves significantly a MCTS solver to take into account bounds on the possible scores of a node in order to select the nodes to explore. We apply our algorithm to solving Seki in the game of Go and to Connect Four.
Fermionic bound states in distinct kinklike backgrounds
Energy Technology Data Exchange (ETDEWEB)
Bazeia, D. [Universidade Federal da Paraiba, Departamento de Fisica, Joao Pessoa, Paraiba (Brazil); Mohammadi, A. [Universidade Federal de Campina Grande, Departamento de Fisica, Caixa Postal 10071, Campina Grande, Paraiba (Brazil)
2017-04-15
This work deals with fermions in the background of distinct localized structures in the two-dimensional spacetime. Although the structures have a similar topological character, which is responsible for the appearance of fractionally charged excitations, we want to investigate how the geometric deformations that appear in the localized structures contribute to the change in the physical properties of the fermionic bound states. We investigate the two-kink and compact kinklike backgrounds, and we consider two distinct boson-fermion interactions, one motivated by supersymmetry and the other described by the standard Yukawa coupling. (orig.)
Persistence-Based Branch Misprediction Bounds for WCET Analysis
DEFF Research Database (Denmark)
Puffitsch, Wolfgang
2015-01-01
Branch prediction is an important feature of pipelined processors to achieve high performance. However, it can lead to overly pessimistic worst-case execution time (WCET) bounds when being modeled too conservatively. This paper presents bounds on the number of branch mispredictions for local...... linear programming formulations of the WCET problem. An evaluation on a number of benchmarks shows that with these bounds, dynamic branch prediction does not necessarily lead to higher WCET bounds than static prediction schemes....
A Beta-Beta Achievability Bound with Applications
Yang, Wei; Collins, Austin; Durisi, Giuseppe; Polyanskiy, Yury; Poor, H. Vincent
2016-01-01
A channel coding achievability bound expressed in terms of the ratio between two Neyman-Pearson $\\beta$ functions is proposed. This bound is the dual of a converse bound established earlier by Polyanskiy and Verd\\'{u} (2014). The new bound turns out to simplify considerably the analysis in situations where the channel output distribution is not a product distribution, for example due to a cost constraint or a structural constraint (such as orthogonality or constant composition) on the channel...
Distinguishing Majorana bound states and Andreev bound states with microwave spectra
Zhang, Zhen-Tao
2018-04-01
Majorana fermions are a fascinating and not yet confirmed quasiparticles in condensed matter physics. Here we propose using microwave spectra to distinguish Majorana bound states (MBSs) from topological trivial Andreev bound states. By numerically calculating the transmission and Zeeman field dependence of the many-body excitation spectrum of a 1D Josephson junction, we find that the two kinds of bound states have distinct responses to variations in the related parameters. Furthermore, the singular behaviors of the MBSs spectrum could be attributed to the robust fractional Josephson coupling and nonlocality of MBSs. Our results provide a feasible method to verify the existence of MBSs and could accelerate its application to topological quantum computation.
Candidate for laser cooling of a negative ion: observations of bound-bound transitions in La(-).
Walter, C W; Gibson, N D; Matyas, D J; Crocker, C; Dungan, K A; Matola, B R; Rohlén, J
2014-08-08
Despite the tremendous advances in laser cooling of neutral atoms and positive ions, no negatively charged ion has been directly laser cooled. The negative ion of lanthanum, La(-), has been proposed as the best candidate for laser cooling of any atomic anion [ and , Phys. Rev. A 81, 032503 (2010)]. Tunable infrared laser photodetachment spectroscopy is used to measure the bound-state structure of La(-), revealing a spectrum of unprecedented richness with multiple bound-bound electric dipole transitions. The potential laser-cooling transition ((3)F(2)(e)→(3)D(1)(o)) is identified and its excitation energy is measured. The results confirm that La^{-} is a very promising negative ion for laser-cooling applications.
Bounding the number of remarkable values via Jouanolou's theorem
Chèze , Guillaume
2015-01-01
In this article we bound the number of remarkable values of a polynomial vector field. The proof is short and based on Jouanolou's theorem about rational first integrals of planar polynomial derivations. Our bound is given in term of the size of a Newton polygon associated to the vector field. We prove that this bound is almost reached.
Bounding the number of remarkable values via Jouanolou's theorem
Chèze, Guillaume
2015-05-01
In this article we bound the number of remarkable values of a polynomial vector field. The proof is short and based on Jouanolou's theorem about rational first integrals of planar polynomial derivations. Our bound is given in term of the size of a Newton polygon associated to the vector field. We prove that this bound is almost reached.
Bound values for Hall conductivity of heterogeneous medium under ...
Indian Academy of Sciences (India)
Bound values for Hall conductivity under quantum Hall effect (QHE) conditions in inhomogeneous medium has been studied. It is shown that bound values for Hall conductivity differ from bound values for metallic conductivity. This is due to the unusual character of current percolation under quantum Hall effect conditions.
Bounds in the generalized Weber problem under locational uncertainty
DEFF Research Database (Denmark)
Juel, Henrik
1981-01-01
An existing analysis of the bounds on the Weber problem solution under uncertainty is incorrect. For the generalized problem with arbitrary measures of distance, we give easily computable ranges on the bounds and state the conditions under which the exact values of the bounds can be found...... with little computational effort. Numerical examples illustrate the analysis....
Bounds on the capacity of constrained two-dimensional codes
DEFF Research Database (Denmark)
Forchhammer, Søren; Justesen, Jørn
2000-01-01
Bounds on the capacity of constrained two-dimensional (2-D) codes are presented. The bounds of Calkin and Wilf apply to first-order symmetric constraints. The bounds are generalized in a weaker form to higher order and nonsymmetric constraints. Results are given for constraints specified by run...
Bounds for regularity and coregularity of graded modules
Indian Academy of Sciences (India)
In the notations that follow, we introduce some bounding functions which were defined by Brodmann, Matteotti, and Minh in [6]. In case the local base ring (R0, m0) was Artinian, they obtained some bounds for regularity and coregularity of graded modules in terms of these functions. Notation 2.4. (A) To establish the bounds ...
Analytic quantum bounds on Bell inequalities
International Nuclear Information System (INIS)
Filipp, S.; Svozil, K.
2005-01-01
Full text: Can realism be combined with the quantum world? An important tool to investigate in this question are Bell's inequalities and violations thereof - they represent a cornerstone of our present understanding of quantum mechanics and therefore the description of nature. Here we present a simple algebraic method to calculate violations for any measurement arrangements that are maximal in the sense that quantum mechanics does not allow a stronger violation. Having two or more polarization analyzers available and a source producing photon-pairs in arbitrary polarization states Bell-type inequalities tell us which probabilities for measuring the polarization in particular directions are viable in a deterministic theory. Quantum mechanics does not obey these rules, but yields a violation of these inequalities. The questions is to what extent the inequalities are violated. Making use of a min-max principle analytical expressions can be found for the 'fine structure' of the maximal violations of arbitrary Bell-like inequalities, i. e. the upper bound reachable by any state when the analyzers measure in given directions. Knowing these bounds is useful for experimental tests of the validity of quantum mechanics and can serve as a prerequisite to answer the even more pressing question, why no stronger violation has been observed until now. (author)
Bounds for phylogenetic network space metrics.
Francis, Andrew; Huber, Katharina T; Moulton, Vincent; Wu, Taoyang
2018-04-01
Phylogenetic networks are a generalization of phylogenetic trees that allow for representation of reticulate evolution. Recently, a space of unrooted phylogenetic networks was introduced, where such a network is a connected graph in which every vertex has degree 1 or 3 and whose leaf-set is a fixed set X of taxa. This space, denoted [Formula: see text], is defined in terms of two operations on networks-the nearest neighbor interchange and triangle operations-which can be used to transform any network with leaf set X into any other network with that leaf set. In particular, it gives rise to a metric d on [Formula: see text] which is given by the smallest number of operations required to transform one network in [Formula: see text] into another in [Formula: see text]. The metric generalizes the well-known NNI-metric on phylogenetic trees which has been intensively studied in the literature. In this paper, we derive a bound for the metric d as well as a related metric [Formula: see text] which arises when restricting d to the subset of [Formula: see text] consisting of all networks with [Formula: see text] vertices, [Formula: see text]. We also introduce two new metrics on networks-the SPR and TBR metrics-which generalize the metrics on phylogenetic trees with the same name and give bounds for these new metrics. We expect our results to eventually have applications to the development and understanding of network search algorithms.
Generalized bounds for convex multistage stochastic programs
Künzi, H; Fandel, G; Trockel, W; Basile, A; Drexl, A; Dawid, H; Inderfurth, K; Kürsten, W; Schittko, U
2005-01-01
This work was completed during my tenure as a scientific assistant and d- toral student at the Institute for Operations Research at the University of St. Gallen. During that time, I was involved in several industry projects in the field of power management, on the occasion of which I was repeatedly c- fronted with complex decision problems under uncertainty. Although usually hard to solve, I quickly learned to appreciate the benefit of stochastic progr- ming models and developed a strong interest in their theoretical properties. Motivated both by practical questions and theoretical concerns, I became p- ticularly interested in the art of finding tight bounds on the optimal value of a given model. The present work attempts to make a contribution to this important branch of stochastic optimization theory. In particular, it aims at extending some classical bounding methods to broader problem classes of practical relevance. This book was accepted as a doctoral thesis by the University of St. Gallen in June 2004.1...
On Aharonov-Casher bound states
Energy Technology Data Exchange (ETDEWEB)
Silva, E.O. [Universidade Federal do Maranhao, Departamento de Fisica, Sao Luis, MA (Brazil); Andrade, F.M. [Universidade Estadual de Ponta Grossa, Departamento de Matematica e Estatistica, Ponta Grossa, PR (Brazil); Filgueiras, C. [Universidade Federal de Campina Grande, Departamento de Fisica, Caixa Postal 10071, Campina Grande, PB (Brazil); Belich, H. [Universidade Federal do Espirito Santo, Departamento de Fisica e Quimica, Vitoria, ES (Brazil)
2013-04-15
In this work bound states for the Aharonov-Casher problem are considered. According to Hagen's work on the exact equivalence between spin-1/2 Aharonov-Bohm and Aharonov-Casher effects, is known that the {nabla}.E term cannot be neglected in the Hamiltonian if the spin of particle is considered. This term leads to the existence of a singular potential at the origin. By modeling the problem by boundary conditions at the origin which arises by the self-adjoint extension of the Hamiltonian, we derive for the first time an expression for the bound state energy of the Aharonov-Casher problem. As an application, we consider the Aharonov-Casher plus a two-dimensional harmonic oscillator. We derive the expression for the harmonic oscillator energies and compare it with the expression obtained in the case without singularity. At the end, an approach for determination of the self-adjoint extension parameter is given. In our approach, the parameter is obtained essentially in terms of physics of the problem. (orig.)
Characterization of bound residues in plants
International Nuclear Information System (INIS)
Stratton, G.D. Jr.; Wheeler, W.B.
1986-01-01
The characterization of unextractable (or 'bound') pesticide residues in plants can be difficult owing to the insoluble nature of the pesticide-plant complex. An unextractable residue can be defined as material derived from the applied pesticide which remains in the plant matrix after exhaustive organic solvent extraction. Experiments with a variety of pesticide classes in plants indicate that the level of unextractable residue varies with the plant species, the pesticide and the exposure time of the plant to the pesticide. Methods used in attempts to release 'bound' residues from solvent-extracted plant tissues include acid hydrolyses, enzymatic treatments and techniques of high-temperature distillation. These methods solubilize or release varying amounts of unextractable material; the amounts depend on the pesticide and on the extent to which the plant fibre is degraded. In experiments using radiolabelled dieldrin (1, 2, 3, 4, 10, 10-hexachloro-6, 7-epoxy-1, 4, 4a, 5, 6, 7, 8, 8a-octahydro-exo-1, 4-endo-5,6-dimethanonaphthalene), carbofuran (2,3-dihydro-2, 2-dimethylbenzofuran-7-yl methylcarbamate) and permethrin ([3-phenoxybenzyl(+-)-3-(2, 2-dichlorovinyl)-2, 2-dimethylcyclopropanecarboxylate]) in radishes, portions of the unextractable material solubilized by the above methods were identified as parent compound and/or closely related metabolites. The bioavailability and toxicological significance of unextractable pesticide residues need to be evaluated. (author)
Phenomenological bounds in inclusive neutrino interactions
International Nuclear Information System (INIS)
Aubrecht, G.J. II; Takasugi, E.; Tanaka, K.
1975-01-01
Using expressions for the ν and anti ν charged and neutral current cross sections and the electroproduction structure function integral and positivity requirements of the sea contribution, bounds are obtained on sigma/sup anti nu N//sigma/sup anti nu N/, and sigma/sup anti nu N//sub nc//sigma/sup nu N//sub nc/ in the standard model. A bound on sigma/sup anti nu N//sigma/sup nu N/ obtained with a V + A term anti p'γ/sub mu/(1-γ 5 )n is used to rule out such a term in the current. A plot of sigma/sup nu N//sub nc/ + sigma/sup anti nu N//sub nc/ versus sigma/sup nu N//sub nc/ - sigma/sup anti nu N//sub nc/ is introduced to analyze the neutral current data. A new relation connecting moments of y and y distributions at a particular point y/sub n/ for ν and anti ν interactions is found. The results do not depend on the neutral current data
The earthworm gastrointestinal effect on the release of organic bound residues in soils
Du, J. H.
2018-03-01
Earthworm activities promote the release of bound residues and the digestive activities of earthworms contribute to the process. Earthworm digestive effects on bound residues can be divided into physical and chemical effects. Physical effects include gastrointestinal abrasion and mixing. The abrasion of soil and litter residues in earthworm gizzards and intestine can grind the food into fine particles, which increase the contact surface with microbial and promote the desorption of bound residues. Chemical effects are attributed to the secreted surfactant substances and digestive enzymes. The surfactants, especially at levels that lead to micellization, can enhance the desorption process of the organic contaminants that sored in the soil. The enzymes in earthworm digestive tracts can decompose the humus in soil, which may promote the release of organic residues that bind with humus.
Parallel Branch-and-Bound Methods for the Job Shop Scheduling
DEFF Research Database (Denmark)
Clausen, Jens; Perregaard, Michael
1998-01-01
for the JSS problem, but with limited success. Even with recent methods, it is still not possible to solve problems substantially larger than 10 machines and 10 jobs. In the current study, we focus on parallel methods for solving JSS problems. We implement two different parallel branch-and-bound algorithms......Job-shop scheduling (JSS) problems are among the more difficult to solve in the class of NP-complete problems. The only successful approach has been branch-and-bound based algorithms, but such algorithms depend heavily on good bound functions. Much work has been done to identify such functions...... for JSS on a 16-processor MEIKO computing surface with Intel i860 processors and perform extensive computational testing using classical publicly available benchmark problems. The parallel part of one of the implementations is based on a similar parallel code for quadratic assignment problems. Results...
A Forest of Sub-1.5-nm-wide Single-Walled Carbon Nanotubes over an Engineered Alumina Support
Yang, Ning; Li, Meng; Patscheider, Jörg; Youn, Seul Ki; Park, Hyung Gyu
2017-04-01
A precise control of the dimension of carbon nanotubes (CNTs) in their vertical array could enable many promising applications in various fields. Here, we demonstrate the growth of vertically aligned, single-walled CNTs (VA-SWCNTs) with diameters in the sub-1.5-nm range (0.98 ± 0.24 nm), by engineering a catalyst support layer of alumina via thermal annealing followed by ion beam treatment. We find out that the ion beam bombardment on the alumina allows the growth of ultra-narrow nanotubes, whereas the thermal annealing promotes the vertical alignment at the expense of enlarged diameters; in an optimal combination, these two effects can cooperate to produce the ultra-narrow VA-SWCNTs. According to micro- and spectroscopic characterizations, ion beam bombardment amorphizes the alumina surface to increase the porosity, defects, and oxygen-laden functional groups on it to inhibit Ostwald ripening of catalytic Fe nanoparticles effectively, while thermal annealing can densify bulk alumina to prevent subsurface diffusion of the catalyst particles. Our findings contribute to the current efforts of precise diameter control of VA-SWCNTs, essential for applications such as membranes and energy storage devices.
On the Applicability of Lower Bounds for Solving Rectilinear
DEFF Research Database (Denmark)
Clausen, Jens; Karisch, Stefan E.; Perregaard, M.
1998-01-01
The quadratic assignment problem (QAP) belongs to the hard core of NP-hard optimization problems. After almost forty years of research only relatively small instances can be solved to optimality. The reason is that the quality of the lower bounds available for exact methods is not sufficient....... Recently, lower bounds based on decomposition were proposed for the so called rectilinear QAP that proved to be the strongest for a large class of problem instances. We investigate the strength of these bounds when applied not only at the root node of a search tree but as the bound function used...... in a Branch-and-Bound code solving large scale QAPs....
Degenerate quantum codes and the quantum Hamming bound
International Nuclear Information System (INIS)
Sarvepalli, Pradeep; Klappenecker, Andreas
2010-01-01
The parameters of a nondegenerate quantum code must obey the Hamming bound. An important open problem in quantum coding theory is whether the parameters of a degenerate quantum code can violate this bound for nondegenerate quantum codes. In this article we show that Calderbank-Shor-Steane (CSS) codes, over a prime power alphabet q≥5, cannot beat the quantum Hamming bound. We prove a quantum version of the Griesmer bound for the CSS codes, which allows us to strengthen the Rains' bound that an [[n,k,d
Tight bounds on computing error-correcting codes by bounded-depth circuits with arbitrary gates
Czech Academy of Sciences Publication Activity Database
Gál, A.; Hansen, A. K.; Koucký, Michal; Pudlák, Pavel; Viola, E.
2013-01-01
Roč. 59, č. 10 (2013), s. 6611-6627 ISSN 0018-9448 R&D Projects: GA AV ČR IAA100190902 Institutional support: RVO:67985840 Keywords : bounded-depth circuits * error-correcting codes * hashing Subject RIV: BA - General Mathematics Impact factor: 2.650, year: 2013 http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6578188
Bounds on dissipation in stress driven flow in a rotating frame
Tang, W.; Caulfield, C. P.; Young, W. R.
2004-11-01
We calculate the optimal upper bound and a rigorous lower bound, subject to the assumption of streamwise invariance, on the long-time-averaged mechanical energy dissipation rate l E within the rotating flow of an incompressible viscous fluid of constant kinematic viscosity ν, depth h and rotational rate f, driven by a constant surface stress τ=ρ u^2_*, where u_* is the friction velocity. We show that l E ≤ l E_max=l E_Stokes, i.e. the dissipation is bounded above by the dissipation associated with the Stokes flow. Using an approach similar to the variational ``background method'', we also generate a rigorous lower bound on the energy dissipation rate, subject to the constraints of total power balance and streamwise momentum balance, in the inviscid limit for fixed values of GE^2, where G=τ h^2/(ρ ν^2) is the Grashof number and E=ν/fh^2 is the Ekman number. Assuming streamwise invariance as G arrow ∞ or equivalently Earrow 0, and by restricting our attention to utilizing a particular, analytically tractable, class of background shear profiles as the Lagrangian multiplier imposing mean streamwise momentum balance, we show that l E ≥ l E_min=2√3 u_*^3/h, a bound that is independent of the flow viscosity.
Calculations of some weakly bound diatomic molecular negative ions
International Nuclear Information System (INIS)
Li, Y.; Lin, C.D.
1999-01-01
We examine the existence of stable bound states of some diatomic molecular ions where the neutral molecule itself is either unbound or barely bound. Two bound states have been found for the HeH - ion even though HeH is known to be unbound. We have found no bound states for He 2 - even though 4 He 2 is known to have one bound state. The predicted binding energies for HeH - are of the order of 1 K and depend sensitively on the isotope combinations. Other weakly bound negative ions such as NeH - and ArH - have also been investigated. These weakly bound molecular ions are good candidates for cold collision experiments. copyright 1999 The American Physical Society
Congeniality bounds on quark masses from nucleosynthesis
Ali, M. Hossain; Hossain, M. Jakir; Tariq, Abdullah Shams Bin
2013-08-01
The work of Jaffe, Jenkins and Kimchi [Phys. Rev. D 79, 065014 (2009)] is revisited to see if indeed the region of congeniality found in their analysis survives further restrictions from nucleosynthesis. It is observed that much of their congenial region disappears when imposing conditions required to produce the correct and required abundances of the primordial elements as well as ensure that stars can continue to burn hydrogen nuclei to form helium as the first step in forming heavier elements in stellar nucleosynthesis. The remaining region is a very narrow slit reduced in width from around 29 MeV found by Jaffe et al. to only about 2.2 MeV in the difference of the nucleon/quark masses. Further bounds on δmq/mq seem to reduce even this narrow slit to the physical point itself.
'Critical' behaviour of weakly bound systems
International Nuclear Information System (INIS)
Lassaut, M.; Lombard, R.J.; Bulboaca, I.
1995-11-01
The class of 3-dimensional finite range or similar potentials λW(r) is discussed, depending on a strength constant λ. The behaviour of the eigenvalue E as function of λ-λ c is studied, where λ c is the critical value at the transition from 0 → 1 bound state. For the l=0 case, E α (λ-λ c ) 2 was found, whereas the relationship is linear for l≥1. Treating l as a continuous parameter in the radial Schroedinger equation, the evolution of the power-law between l=0 and l=1 is given. Besides spherically symmetric scalar potentials, the case of a repulsive scalar potential combined with a spin-orbit component of the Thomas form is also discussed. (author)
Frenetic Bounds on the Entropy Production
Maes, Christian
2017-10-01
We give a systematic derivation of positive lower bounds for the expected entropy production (EP) rate in classical statistical mechanical systems obeying a dynamical large deviation principle. The logic is the same for the return to thermodynamic equilibrium as it is for steady nonequilibria working under the condition of local detailed balance. We recover there recently studied "uncertainty" relations for the EP, appearing in studies about the effectiveness of mesoscopic machines. In general our refinement of the positivity of the expected EP rate is obtained in terms of a positive and even function of the expected current(s) which measures the dynamical activity in the system, a time-symmetric estimate of the changes in the system's configuration. Also underdamped diffusions can be included in the analysis.
Helioscope bounds on hidden sector photons
International Nuclear Information System (INIS)
Redondo, J.
2008-01-01
The flux of hypothetical ''hidden photons'' from the Sun is computed under the assumption that they interact with normal matter only through kinetic mixing with the ordinary standard model photon. Requiring that the exotic luminosity is smaller than the standard photon luminosity provides limits for the mixing parameter down to χ -14 , depending on the hidden photon mass. Furthermore, it is pointed point out that helioscopes looking for solar axions are also sensitive to hidden photons. The recent results of the CAST collaboration are used to further constrain the mixing parameter χ at low masses (m γ' <1 eV) where the luminosity bound is weaker. In this regime the solar hidden photon ux has a sizable contribution of longitudinally polarized hidden photons of low energy which are invisible for current helioscopes. (orig.)
Classical bound for Mach-Zehnder superresolution.
Afek, I; Ambar, O; Silberberg, Y
2010-03-26
The employment of path-entangled multiphoton states enables measurement of phase with enhanced precision. It is common practice to demonstrate the unique properties of such quantum states by measuring superresolving oscillations in the coincidence rate of a Mach-Zehnder interferometer. Similar oscillations, however, have also been demonstrated in various configurations using classical light only; making it unclear what, if any, are the classical limits of this phenomenon. Here we derive a classical bound for the visibility of superresolving oscillations in a Mach-Zehnder interferometer. This provides an easy to apply, fundamental test of nonclassicality. We apply this test to experimental multiphoton coincidence measurements obtained using photon number resolving detectors. Mach-Zehnder superresolution is found to be a highly distinctive quantum effect.
Volume Stability of Bitumen Bound Building Blocks
Directory of Open Access Journals (Sweden)
Thanaya I.N.A.
2010-01-01
Full Text Available This paper covers results of laboratory investigations on the volume stability of masonry units incorporating waste materials bound with bitumen (Bitublocks, due to moisture adsorption, thermal exposure and vacuum saturation. The materials used were steel slag, crushed glass, coal fly ash, and 50 pen bitumen. The samples were produced in hot mix method, compacted, then exposed to moist and temperature. It was found that moisture adsorption from the environment caused the Bitublock to expand. The samples with less intense curing regime experienced lower expansion and became stable faster, and vice versa. Under thermal condition (at 70°C, the samples with less intense curing regime underwent higher expansion, and vice versa. They were also highly reversible. Their volume stability was found unique under water exposure. The expansion on first vacuum saturation cycle was irreversible, then largely reversible on the following cycles.
Upper bounds for flexoelectric coefficients in ferroelectrics
Yudin, P. V.; Ahluwalia, R.; Tagantsev, A. K.
2014-02-01
Flexoelectric effect is the response of electric polarization to the mechanical strain gradient. At the nano-scale, where large strain gradients are expected, the flexoelectric effect becomes appreciable and may substitute piezoelectric effect in centrosymmetric materials. These features make flexoelectricity of growing interest during the last decade. At the same time, the available theoretical and experimental results are rather contradictory. In particular, experimentally measured flexoelectric coefficients in some ferroelectric materials largely exceed theoretically predicted values. Here, we determine the upper limits for the magnitude of the static bulk contribution to the flexoelectric effect in ferroelectrics, the contribution which was customarily considered as the dominating one. The magnitude of the upper bounds obtained suggests that the anomalously high flexoelectric coupling documented for perovskite ceramics can hardly be attributed to a manifestation of the static bulk effect.
Resignation syndrome: Catatonia? Culture-bound?
Directory of Open Access Journals (Sweden)
Karl eSallin
2016-01-01
Full Text Available Resignation syndrome (RS designates a long-standing disorder predominately affecting psychologically traumatised children and adolescents in the midst of a strenuous and lengthy migration process. Typically a depressive onset is followed by gradual withdrawal progressing via stupor into a state that prompts tube feeding and is characterised by failure to respond even to painful stimuli. The patient is seemingly unconscious. Recovery ensues within months to years and is claimed to be dependent on the restoration of hope to the family.Descriptions of disorders resembling RS can be found in the literature and the condition is unlikely novel. Nevertheless, the magnitude and geographical distribution stand out. Several hundred cases have been reported exclusively in Sweden in the past decade prompting the Swedish National Board of Health and Welfare to recognise RS as a separate diagnostic entity. The currently prevailing stress hypothesis fails to account for the regional distribution and contributes little to treatment. Consequently, a re-evaluation of diagnostics and treatment is required. Psychogenic catatonia is proposed to supply the best fit with the clinical presentation. Treatment response, altered brain metabolism or preserved awareness would support this hypothesis.Epidemiological data suggests culture-bound beliefs and expectations to generate and direct symptom expression and we argue that culture-bound psychogenesis can accommodate the endemic distribution.Last, we review recent models of predictive coding indicating how expectation processes are crucially involved in the placebo and nocebo effect, delusions and conversion disorders. Building on this theoretical framework we propose a neurobiological model of RS in which the impact of overwhelming negative expectations are directly causative of the down-regulation of higher order and lower order behavioural systems in particularly vulnerable individuals.
Resignation Syndrome: Catatonia? Culture-Bound?
Sallin, Karl; Lagercrantz, Hugo; Evers, Kathinka; Engström, Ingemar; Hjern, Anders; Petrovic, Predrag
2016-01-01
Resignation syndrome (RS) designates a long-standing disorder predominately affecting psychologically traumatized children and adolescents in the midst of a strenuous and lengthy migration process. Typically a depressive onset is followed by gradual withdrawal progressing via stupor into a state that prompts tube feeding and is characterized by failure to respond even to painful stimuli. The patient is seemingly unconscious. Recovery ensues within months to years and is claimed to be dependent on the restoration of hope to the family. Descriptions of disorders resembling RS can be found in the literature and the condition is unlikely novel. Nevertheless, the magnitude and geographical distribution stand out. Several hundred cases have been reported exclusively in Sweden in the past decade prompting the Swedish National Board of Health and Welfare to recognize RS as a separate diagnostic entity. The currently prevailing stress hypothesis fails to account for the regional distribution and contributes little to treatment. Consequently, a re-evaluation of diagnostics and treatment is required. Psychogenic catatonia is proposed to supply the best fit with the clinical presentation. Treatment response, altered brain metabolism or preserved awareness would support this hypothesis. Epidemiological data suggests culture-bound beliefs and expectations to generate and direct symptom expression and we argue that culture-bound psychogenesis can accommodate the endemic distribution. Last, we review recent models of predictive coding indicating how expectation processes are crucially involved in the placebo and nocebo effect, delusions and conversion disorders. Building on this theoretical framework we propose a neurobiological model of RS in which the impact of overwhelming negative expectations are directly causative of the down-regulation of higher order and lower order behavioral systems in particularly vulnerable individuals.
Resignation Syndrome: Catatonia? Culture-Bound?
Sallin, Karl; Lagercrantz, Hugo; Evers, Kathinka; Engström, Ingemar; Hjern, Anders; Petrovic, Predrag
2016-01-01
Resignation syndrome (RS) designates a long-standing disorder predominately affecting psychologically traumatized children and adolescents in the midst of a strenuous and lengthy migration process. Typically a depressive onset is followed by gradual withdrawal progressing via stupor into a state that prompts tube feeding and is characterized by failure to respond even to painful stimuli. The patient is seemingly unconscious. Recovery ensues within months to years and is claimed to be dependent on the restoration of hope to the family. Descriptions of disorders resembling RS can be found in the literature and the condition is unlikely novel. Nevertheless, the magnitude and geographical distribution stand out. Several hundred cases have been reported exclusively in Sweden in the past decade prompting the Swedish National Board of Health and Welfare to recognize RS as a separate diagnostic entity. The currently prevailing stress hypothesis fails to account for the regional distribution and contributes little to treatment. Consequently, a re-evaluation of diagnostics and treatment is required. Psychogenic catatonia is proposed to supply the best fit with the clinical presentation. Treatment response, altered brain metabolism or preserved awareness would support this hypothesis. Epidemiological data suggests culture-bound beliefs and expectations to generate and direct symptom expression and we argue that culture-bound psychogenesis can accommodate the endemic distribution. Last, we review recent models of predictive coding indicating how expectation processes are crucially involved in the placebo and nocebo effect, delusions and conversion disorders. Building on this theoretical framework we propose a neurobiological model of RS in which the impact of overwhelming negative expectations are directly causative of the down-regulation of higher order and lower order behavioral systems in particularly vulnerable individuals. PMID:26858615
Bound states and molecular structure of systems with hyperons
International Nuclear Information System (INIS)
Akaishi, Y.
1992-01-01
Microscopic calculations are done for Σ-hypernuclear few-body systems by a method named ATMS. Among two- to five-body systems, only the Σ 4 He(0 + ) and Σ 4 H(0 + ) hypernuclei are expected to be bound: The binding energy and the width of the former are calculated to be 3.7 ∼ 4.6 MeV and 4.5 ∼ 7.9 MeV, respectively. The observation of Σ 4 He at KEK is in good agreement with the above prediction. The nucleus-Σ potential has a strong Lane term and a repulsive bump at short distance. The Lane term makes the system bound and the bump suppresses the ΣN → ΛN conversion. X-ray measurement of level shifts in the 4 He-Σ - , 3 He-Σ - and 3 H-Σ - atoms can provide another information on the Lane term. In 208 Pb, there may exist a peculiar state, Coulomb-assisted (atomnucleus) hybrid state, where Σ - is trapped in the surface region by the strong interaction with the aid of the inner centrifugal repulsion and the outer Coulomb attraction. An analysis is given for new data of Ξ -.12 C atomic or nuclear systems from the emulsion-counter experiment at KEK. The double-Λ hypernucleus formation rate is calculated for a stopped Ξ - on 4 He. A high branching ratio of 37% is obtained for the ΛΛ 4 H formation from a Ξ -.4 He atom. The detection of about 2.3 MeV neutron is proposed to search for lightest double-Λ hypernucleus ΛΛ 4 H. (author)
Extreme hydrothermal conditions at an active plate-bounding fault
Sutherland, Rupert; Townend, John; Toy, Virginia; Upton, Phaedra; Coussens, Jamie; Allen, Michael; Baratin, Laura-May; Barth, Nicolas; Becroft, Leeza; Boese, Carolin; Boles, Austin; Boulton, Carolyn; Broderick, Neil G. R.; Janku-Capova, Lucie; Carpenter, Brett M.; Célérier, Bernard; Chamberlain, Calum; Cooper, Alan; Coutts, Ashley; Cox, Simon; Craw, Lisa; Doan, Mai-Linh; Eccles, Jennifer; Faulkner, Dan; Grieve, Jason; Grochowski, Julia; Gulley, Anton; Hartog, Arthur; Howarth, Jamie; Jacobs, Katrina; Jeppson, Tamara; Kato, Naoki; Keys, Steven; Kirilova, Martina; Kometani, Yusuke; Langridge, Rob; Lin, Weiren; Little, Timothy; Lukacs, Adrienn; Mallyon, Deirdre; Mariani, Elisabetta; Massiot, Cécile; Mathewson, Loren; Melosh, Ben; Menzies, Catriona; Moore, Jo; Morales, Luiz; Morgan, Chance; Mori, Hiroshi; Niemeijer, Andre; Nishikawa, Osamu; Prior, David; Sauer, Katrina; Savage, Martha; Schleicher, Anja; Schmitt, Douglas R.; Shigematsu, Norio; Taylor-Offord, Sam; Teagle, Damon; Tobin, Harold; Valdez, Robert; Weaver, Konrad; Wiersberg, Thomas; Williams, Jack; Woodman, Nick; Zimmer, Martin
2017-06-01
Temperature and fluid pressure conditions control rock deformation and mineralization on geological faults, and hence the distribution of earthquakes. Typical intraplate continental crust has hydrostatic fluid pressure and a near-surface thermal gradient of 31 ± 15 degrees Celsius per kilometre. At temperatures above 300-450 degrees Celsius, usually found at depths greater than 10-15 kilometres, the intra-crystalline plasticity of quartz and feldspar relieves stress by aseismic creep and earthquakes are infrequent. Hydrothermal conditions control the stability of mineral phases and hence frictional-mechanical processes associated with earthquake rupture cycles, but there are few temperature and fluid pressure data from active plate-bounding faults. Here we report results from a borehole drilled into the upper part of the Alpine Fault, which is late in its cycle of stress accumulation and expected to rupture in a magnitude 8 earthquake in the coming decades. The borehole (depth 893 metres) revealed a pore fluid pressure gradient exceeding 9 ± 1 per cent above hydrostatic levels and an average geothermal gradient of 125 ± 55 degrees Celsius per kilometre within the hanging wall of the fault. These extreme hydrothermal conditions result from rapid fault movement, which transports rock and heat from depth, and topographically driven fluid movement that concentrates heat into valleys. Shear heating may occur within the fault but is not required to explain our observations. Our data and models show that highly anomalous fluid pressure and temperature gradients in the upper part of the seismogenic zone can be created by positive feedbacks between processes of fault slip, rock fracturing and alteration, and landscape development at plate-bounding faults.
Extreme hydrothermal conditions at an active plate-bounding fault.
Sutherland, Rupert; Townend, John; Toy, Virginia; Upton, Phaedra; Coussens, Jamie; Allen, Michael; Baratin, Laura-May; Barth, Nicolas; Becroft, Leeza; Boese, Carolin; Boles, Austin; Boulton, Carolyn; Broderick, Neil G R; Janku-Capova, Lucie; Carpenter, Brett M; Célérier, Bernard; Chamberlain, Calum; Cooper, Alan; Coutts, Ashley; Cox, Simon; Craw, Lisa; Doan, Mai-Linh; Eccles, Jennifer; Faulkner, Dan; Grieve, Jason; Grochowski, Julia; Gulley, Anton; Hartog, Arthur; Howarth, Jamie; Jacobs, Katrina; Jeppson, Tamara; Kato, Naoki; Keys, Steven; Kirilova, Martina; Kometani, Yusuke; Langridge, Rob; Lin, Weiren; Little, Timothy; Lukacs, Adrienn; Mallyon, Deirdre; Mariani, Elisabetta; Massiot, Cécile; Mathewson, Loren; Melosh, Ben; Menzies, Catriona; Moore, Jo; Morales, Luiz; Morgan, Chance; Mori, Hiroshi; Niemeijer, Andre; Nishikawa, Osamu; Prior, David; Sauer, Katrina; Savage, Martha; Schleicher, Anja; Schmitt, Douglas R; Shigematsu, Norio; Taylor-Offord, Sam; Teagle, Damon; Tobin, Harold; Valdez, Robert; Weaver, Konrad; Wiersberg, Thomas; Williams, Jack; Woodman, Nick; Zimmer, Martin
2017-06-01
Temperature and fluid pressure conditions control rock deformation and mineralization on geological faults, and hence the distribution of earthquakes. Typical intraplate continental crust has hydrostatic fluid pressure and a near-surface thermal gradient of 31 ± 15 degrees Celsius per kilometre. At temperatures above 300-450 degrees Celsius, usually found at depths greater than 10-15 kilometres, the intra-crystalline plasticity of quartz and feldspar relieves stress by aseismic creep and earthquakes are infrequent. Hydrothermal conditions control the stability of mineral phases and hence frictional-mechanical processes associated with earthquake rupture cycles, but there are few temperature and fluid pressure data from active plate-bounding faults. Here we report results from a borehole drilled into the upper part of the Alpine Fault, which is late in its cycle of stress accumulation and expected to rupture in a magnitude 8 earthquake in the coming decades. The borehole (depth 893 metres) revealed a pore fluid pressure gradient exceeding 9 ± 1 per cent above hydrostatic levels and an average geothermal gradient of 125 ± 55 degrees Celsius per kilometre within the hanging wall of the fault. These extreme hydrothermal conditions result from rapid fault movement, which transports rock and heat from depth, and topographically driven fluid movement that concentrates heat into valleys. Shear heating may occur within the fault but is not required to explain our observations. Our data and models show that highly anomalous fluid pressure and temperature gradients in the upper part of the seismogenic zone can be created by positive feedbacks between processes of fault slip, rock fracturing and alteration, and landscape development at plate-bounding faults.
Substrate-bound growth of Au-Pd diblock nanowire and hybrid nanorod-plate
He, Jiating; Wang, Yawen; Fan, Zhanxi; Lam, Zhenhui; Zhang, Hua; Liu, Bin; Chen, Hongyu
2015-04-01
We expand the scope of the previously developed Active Surface Growth mode for growing substrate-bound ultrathin Pd (d = 4 nm) and Ag nanowires (d = 30 nm) in aqueous solution under ambient conditions. Using Au nanorods as the seeds, selective growth at the contact line between the rod and the substrate eventually leads to an attached Pd nanoplate. The unique growth mode also allows sequential growth of different materials via a single seed, giving substrate-bound Au-Pd diblock nanowires. The new abilities to use seed shape to pre-define the active sites and to apply sequential growth open windows for new pathways to hybrid nanostructures.We expand the scope of the previously developed Active Surface Growth mode for growing substrate-bound ultrathin Pd (d = 4 nm) and Ag nanowires (d = 30 nm) in aqueous solution under ambient conditions. Using Au nanorods as the seeds, selective growth at the contact line between the rod and the substrate eventually leads to an attached Pd nanoplate. The unique growth mode also allows sequential growth of different materials via a single seed, giving substrate-bound Au-Pd diblock nanowires. The new abilities to use seed shape to pre-define the active sites and to apply sequential growth open windows for new pathways to hybrid nanostructures. Electronic supplementary information (ESI) available: Supporting TEM and SEM images of control experiments with different reaction conditions and another type of diblock nanowires. See DOI: 10.1039/c5nr00361j
The neural basis of bounded rational behavior
Directory of Open Access Journals (Sweden)
Coricelli, Giorgio
2012-03-01
Full Text Available Bounded rational behaviour is commonly observed in experimental games and in real life situations. Neuroeconomics can help to understand the mental processing underlying bounded rationality and out-of-equilibrium behaviour. Here we report results from recent studies on the neural basis of limited steps of reasoning in a competitive setting —the beauty contest game. We use functional magnetic resonance imaging (fMRI to study the neural correlates of human mental processes in strategic games. We apply a cognitive hierarchy model to classify subject’s choices in the experimental game according to the degree of strategic reasoning so that we can identify the neural substrates of different levels of strategizing. We found a correlation between levels of strategic reasoning and activity in a neural network related to mentalizing, i.e. the ability to think about other’s thoughts and mental states. Moreover, brain data showed how complex cognitive processes subserve the higher level of reasoning about others. We describe how a cognitive hierarchy model fits both behavioural and brain data.
La racionalidad limitada es un fenómeno observado de manera frecuente tanto en juegos experimentales como en situaciones cotidianas. La Neuroeconomía puede mejorar la comprensión de los procesos mentales que caracterizan la racionalidad limitada; en paralelo nos puede ayudar a comprender comportamientos que violan el equilibrio. Nuestro trabajo presenta resultados recientes sobre la bases neuronales del razonamiento estratégico (y sus límite en juegos competitivos —como el juego del “beauty contest”. Estudiamos las bases neuronales del comportamiento estratégico en juegos con interacción entre sujetos usando resonancia magnética funcional (fMRI. Las decisiones de los participantes se clasifican acorde al grado de razonamiento estratégico: el llamado modelo de Jerarquías Cognitivas. Los resultados muestran una correlación entre niveles de
Introducing an Educational Tool for Learning Branch & Bound Strategy
Directory of Open Access Journals (Sweden)
Sofriesilero Zumaytis
2017-04-01
Full Text Available According to our informal survey, Branch & Bound strategy is considerably difficult to learn compared to other strategies. This strategy consists of several complex algorithmic steps such as Reduced Cost Matrix (RCM calculation and Breadth First Search. Thus, to help students understanding this strategy, AP-BB, an educational tool for learning Branch & Bound is developed. This tool includes four modules which are Brute Force solving visualization, Branch & Bound solving visualization, RCM calculator, and case-based performance comparison. These modules are expected to enhance student’s understanding about Branch & Bound strategy and its characteristics. Furthermore, our work incorporates TSP as its case study and Brute Force strategy as a baseline to provide a concrete impact of Branch & Bound strategy. According to our qualitative evaluation, AP-BB and all of its features fulfil student necessities for learning Branch & Bound strategy.
Sharp bounds for periodic solutions of Lipschitzian differential equations
International Nuclear Information System (INIS)
Zevin, A A
2009-01-01
A general system of Lipschitzian differential equations, containing simultaneously terms without delay and with arbitrary constant and time-varying delays, is considered. For the autonomous case, a lower bound for the period of nonconstant periodic solutions, expressed in the respective supremum Lipschitz constants, is found. For nonautonomous periodic equations, explicit upper bounds for the amplitudes and maximum derivatives of periodic solutions are obtained. For all n ≥ 2, the bounds do not depend on n and, in general, are different from that for n = 1. All the bounds are sharp; they are attained in linear differential equations with piece-wise constant deviating arguments. A relation between the obtained bounds and the sharp bounds in other metrics is established
Architecture-independent power bound for vibration energy harvesters
International Nuclear Information System (INIS)
Halvorsen, E; Le, C P; Mitcheson, P D; Yeatman, E M
2013-01-01
The maximum output power of energy harvesters driven by harmonic vibrations is well known for a range of specific harvester architectures. An architecture-independent bound based on the mechanical input-power also exists and gives a strict limit on achievable power with one mechanical degree of freedom, but is a least upper bound only for lossless devices. We report a new theoretical bound on the output power of vibration energy harvesters that includes parasitic, linear mechanical damping while still being architecture independent. This bound greatly improves the previous bound at moderate force amplitudes and is compared to the performance of established harvester architectures which are shown to agree with it in limiting cases. The bound is a hard limit on achievable power with one mechanical degree of freedom and can not be circumvented by transducer or power-electronic-interface design
Detailed determination of the fusion nuclear radius in reactions involving weakly bound projectiles
International Nuclear Information System (INIS)
Gomez Camacho, A.; Aguilera, E. F.; Quiroz, E. M.
2007-01-01
A detailed determination of the fusion radius parameter is performed within the Distorted Wave Born Approximation for reactions involving weakly bound projectiles. Specifically, a simultaneous X 2- analysis of elastic and fusion cross section data is done using a Woods-Saxon potential with volume and surface parts. The volume part is assumed to be responsible for fusion reactions while the surface part for all other direct reactions. It is proved that in order to fit fusion data, particularly for energies below the Coulomb barrier where fusion is enhanced, it is necessary to have a value of around 1.4 fm for the fusion radial parameter of the fusion potential (W F ). This value is much higher than that frequently used in Barrier Penetration models (1.0 fm). The calculations are performed for reactions involving the weakly bound projectile 9 Be with several medium mass targets. (Author)
Entropic Lower Bound for Distinguishability of Quantum States
Directory of Open Access Journals (Sweden)
Seungho Yang
2015-01-01
Full Text Available For a system randomly prepared in a number of quantum states, we present a lower bound for the distinguishability of the quantum states, that is, the success probability of determining the states in the form of entropy. When the states are all pure, acquiring the entropic lower bound requires only the density operator and the number of the possible states. This entropic bound shows a relation between the von Neumann entropy and the distinguishability.
Upper bounds on minimum cardinality of exact and approximate reducts
Chikalov, Igor
2010-01-01
In the paper, we consider the notions of exact and approximate decision reducts for binary decision tables. We present upper bounds on minimum cardinality of exact and approximate reducts depending on the number of rows (objects) in the decision table. We show that the bound for exact reducts is unimprovable in the general case, and the bound for approximate reducts is almost unimprovable in the general case. © 2010 Springer-Verlag Berlin Heidelberg.
Uniform Bounds for Black--Scholes Implied Volatility
Tehranchi, Michael Rummine
2016-01-01
In this note, Black--Scholes implied volatility is expressed in terms of various optimization problems. From these representations, upper and lower bounds are derived which hold uniformly across moneyness and call price. Various symmetries of the Black--Scholes formula are exploited to derive new bounds from old. These bounds are used to reprove asymptotic formulas for implied volatility at extreme strikes and/or maturities. the Society for Industrial and Applied Mathematics 10.1137/14095248X
Uniform bounds for Black--Scholes implied volatility
Tehranchi, Michael R.
2015-01-01
In this note, Black--Scholes implied volatility is expressed in terms of various optimisation problems. From these representations, upper and lower bounds are derived which hold uniformly across moneyness and call price. Various symmetries of the Black--Scholes formula are exploited to derive new bounds from old. These bounds are used to reprove asymptotic formulae for implied volatility at extreme strikes and/or maturities.
User-Friendly Tail Bounds for Matrix Martingales
2011-01-16
USER-FRIENDLY TAIL BOUNDS FOR MATRIX MARTINGALES JOEL A. TROPP ! Report Documentation Page Form ApprovedOMB No. 0704-0188...00-2011 4. TITLE AND SUBTITLE User-Friendly Tail Bounds for Matrix Martingales 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...BOUNDS FOR MATRIX MARTINGALES JOEL A. TROPP Abstract. This report presents probability inequalities for sums of adapted sequences of random, self
Viewing Majorana Bound States by Rabi Oscillations.
Wang, Zhi; Liang, Qi-Feng; Yao, Dao-Xin; Hu, Xiao
2015-07-08
We propose to use Rabi oscillation as a probe to view the fractional Josepshon relation (FJR) associated with Majorana bound states (MBSs) expected in one-dimensional topological superconductors. The system consists of a quantum dot (QD) and an rf-SQUID with MBSs at the Josephson junction. Rabi oscillations between energy levels formed by MBSs are induced by ac gate voltage controlling the coupling between QD and MBS when the photon energy proportional to the ac frequency matches gap between quantum levels formed by MBSs and QD. As a manifestation of the Rabi oscillation in the whole system involving MBSs, the electron occupation on QD oscillates with time, which can be measured by charge sensing techniques. With Floquet theorem and numerical analysis we reveal that from the resonant driving frequency for coherent Rabi oscillation one can directly map out the FJR cos(πΦ/Φ0) as a signature of MBSs, with Φ the magnetic flux through SQUID and Φ0 = hc/2e the flux quantum. The present scheme is expected to provide a clear evidence for MBSs under intensive searching.
Photochemistry of triarylmethane dyes bound to proteins
Indig, Guilherme L.
1996-04-01
Triarylmethanes represent a class of cationic dyes whose potential as photosensitizers for use in photodynamic therapy of neoplastic diseases has never been comprehensively evaluated. Here, the laser-induced photodecomposition of three triarylmethane dyes, crystal violet, ethyl violet, and malachite green, non-covalently bound to bovine serum albumin (a model biological target) was investigated. Upon laser excitation at 532 nm, the bleaching of the corresponding dye-protein molecular complexes follows spectroscopic patterns that suggest the formation of reduced forms of the dyes as major reaction photoproducts. That implies that an electron or hydrogen atom transfer from the protein to the dye's moiety within the guest-host complex is the first step of the photobleaching process. Since the availability of dissolved molecular oxygen was not identified as a limiting factor for the phototransformations to occur, these dyes can be seen as potential phototherapeutic agents for use in hypoxic areas of tumors. These triarylmethane dyes strongly absorb at relatively long wavelengths (absorption maximum around 600 nm; (epsilon) max approximately equals 105 M-1 cm-1), and only minor changes in their absorption characteristics are observed upon binding to the protein. However the binding event leads to a remarkable increase in their fluorescence quantum yield and photoreactivity.
Surfactant-bound monolithic columns for CEC.
Gu, Congying; He, Jun; Jia, Jinping; Fang, Nenghu; Shamsi, Shahab A
2009-11-01
A novel anionic surfactant bound monolithic stationary phase based on 11-acrylaminoundecanoic acid is designed for CEC. The monolith possessing bonded undecanoyl groups (hydrophobic sites) and carboxyl groups (weak cationic ion-exchange sites) were evaluated as a mixed-mode stationary phase in CEC for the separation of neutral and polar solutes. Using a multivariate D-optimal design the composition of the polymerization mixture was modeled and optimized with five alkylbenzenes and seven alkyl phenyl ketones as test solutes. The D-optimal design indicates a strong dependence of electrochromatographic parameters on the concentration of 11-acrylaminoundecanoic acid monomer and porogen (water) in the polymerization mixture. A difference of 6, 8 and 13% RSD between the predicted and the experimental values in terms of efficiency, resolution and retention time, respectively, indeed confirmed that the proposed approach is practical. The physical (i.e. morphology, porosity and permeability) and chromatographic properties of the monolithic columns were thoroughly investigated. With the optimized monolithic column, high efficiency separation of N-methylcarbamates pesticides and positional isomers was successfully achieved. It appears that this type of mixed-mode monolith (containing both chargeable and hydrophobic sites) may have a great potential as a new generation of CEC stationary phase.
CBC bound proteins and RNA fate
DEFF Research Database (Denmark)
Giacometti, Simone
) complex (CBCN), were recently shown to target capped RNA either toward export or degradation, but the mechanisms by which they can discriminate between different RNA families and route them toward different metabolic pathways still remain unclear. A major question to be answered is how and when...... analysed NEXT-component RBM7. We report that: (i) CBP20, ARS2, PHAX and ZC3H18 bind close to the cap, while RBM7 and MTR4 bind throughout the mRNA body; (ii) CBP20, ARS2, PHAX and ZC3H18 associate with a broad set of RNA polymerase II (PolII)-derived RNAs and have only mild species preferences; (iii......) binding varies with the RNA maturation stage, with the CBC being highly enriched on mature mRNA, ARS2/PHAX/ZC3H18/MTR4 less so, and RMB7 preferentially bound to pre-mRNAs; (iv) MTR4 and RBM7 show different specificities, with RBM7 being highly enriched on introns and promoter upstream transcripts (PROMPTs...
Organically bound tritium analysis in environmental samples
Energy Technology Data Exchange (ETDEWEB)
Baglan, N. [CEA/DAM/DIF, Arpajon (France); Kim, S.B. [AECL, Chalk River Laboratories, Chalk River, ON (Canada); Cossonnet, C. [IRSN/PRP-ENV/STEME/LMRE, Orsay (France); Croudace, I.W.; Warwick, P.E. [GAU-Radioanalytical, University of Southampton, Southampton (United Kingdom); Fournier, M. [IRSN/DG/DMQ, Fontenay-aux-Roses (France); Galeriu, D. [IFIN-HH, Horia-Hulubei, Inst. Phys. and Nucl. Eng., Bucharest (Romania); Momoshima, N. [Kyushu University, Radioisotope Ctr., Fukuoka (Japan); Ansoborlo, E. [CEA/DEN/DRCP/CETAMA, Bagnols-sur-Ceze (France)
2015-03-15
Organically bound tritium (OBT) has become of increased interest within the last decade, with a focus on its behaviour and also its analysis, which are important to assess tritium distribution in the environment. In contrast, there are no certified reference materials and no standard analytical method through the international organization related to OBT. In order to resolve this issue, an OBT international working group was created in May 2012. Over 20 labs from around the world participated and submitted their results for the first intercomparison exercise results on potato (Sep 2013). The samples, specially-prepared potatoes, were provided in March 2013 to each participant. Technical information and results from this first exercise are discussed here for all the labs which have realised the five replicates necessary to allow a reliable statistical treatment. The results are encouraging as the increased number of participating labs did not degrade the observed dispersion of the results for a similar activity level. Therefore, the results do not seem to depend on the analytical procedure used. From this work an optimised procedure can start to be developed to deal with OBT analysis and will guide subsequent planned OBT trials by the international group.
Revisiting cosmological bounds on sterile neutrinos
Energy Technology Data Exchange (ETDEWEB)
Vincent, Aaron C. [Institute for Particle Physics Phenomenology (IPPP), Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Martínez, Enrique Fernández [Departamento and Instituto de Física Teórica (IFT), UAM/CSIC, Universidad Autonoma de Madrid, C/ Nicolás Cabrera 13-15, E-28049 Cantoblanco, Madrid (Spain); Hernández, Pilar; Mena, Olga [Instituto de Física Corpuscular (IFIC), CSIC-Universitat de València, Apartado de Correos 22085, E-46071 Valencia (Spain); Lattanzi, Massimiliano, E-mail: aaron.vincent@durham.ac.uk, E-mail: enrique.fernandez-martinez@uam.es, E-mail: m.pilar.hernandez@uv.es, E-mail: omena@ific.uv.es, E-mail: lattanzi@fe.infn.it [Dipartimento di Fisica e Science della Terra, Università di Ferrara and INFN, sezione di Ferrara, Polo Scientifico e Tecnologico, Edificio C Via Saragat, 1, I-44122 Ferrara (Italy)
2015-04-01
We employ state-of-the art cosmological observables including supernova surveys and BAO information to provide constraints on the mass and mixing angle of a non-resonantly produced sterile neutrino species, showing that cosmology can effectively rule out sterile neutrinos which decay between BBN and the present day. The decoupling of an additional heavy neutrino species can modify the time dependence of the Universe's expansion between BBN and recombination and, in extreme cases, lead to an additional matter-dominated period; while this could naively lead to a younger Universe with a larger Hubble parameter, it could later be compensated by the extra radiation expected in the form of neutrinos from sterile decay. However, recombination-era observables including the Cosmic Microwave Background (CMB), the shift parameter R{sub CMB} and the sound horizon r{sub s} from Baryon Acoustic Oscillations (BAO) severely constrain this scenario. We self-consistently include the full time-evolution of the coupled sterile neutrino and standard model sectors in an MCMC, showing that if decay occurs after BBN, the sterile neutrino is essentially bounded by the constraint sin{sup 2}θ ∼< 0.026 (m{sub s}/eV){sup −2}.
Bounding the Higgs boson width through interferometry.
Dixon, Lance J; Li, Ye
2013-09-13
We study the change in the diphoton-invariant-mass distribution for Higgs boson decays to two photons, due to interference between the Higgs resonance in gluon fusion and the continuum background amplitude for gg→γγ. Previously, the apparent Higgs mass was found to shift by around 100 MeV in the standard model in the leading-order approximation, which may potentially be experimentally observable. We compute the next-to-leading-order QCD corrections to the apparent mass shift, which reduce it by about 40%. The apparent mass shift may provide a way to measure, or at least bound, the Higgs boson width at the Large Hadron Collider through "interferometry." We investigate how the shift depends on the Higgs width, in a model that maintains constant Higgs boson signal yields. At Higgs widths above 30 MeV, the mass shift is over 200 MeV and increases with the square root of the width. The apparent mass shift could be measured by comparing with the ZZ* channel, where the shift is much smaller. It might be possible to measure the shift more accurately by exploiting its strong dependence on the Higgs transverse momentum.
Chernoff bounds for Class-A noise
Energy Technology Data Exchange (ETDEWEB)
Nielsen, P.A.
1991-08-12
The goal is, using a very large passive array, to determine the performance limits of a detector. The signal of interest is narrowband with a Gaussian envelope, and the contaminating noise is multivariate Class-A. Two different multivariate models for the Class A family are presented. One of the models is appropriate for array processing applications. The data is spatially dependent and temporally independent. It is shown, in the spatially independent case, that the Chernoff approximation does closely approximate the performance of the optimal detector. It is shown the approximation improves as the number of samples increases. Unfortunately, it is also shown that the Chernoff approximation requires numerical evaluation of a M-dimensional integral. For the application here, M may be as large as 150, ruling out this approach. Two alternative approaches are examined. First, approximating the Class A model by a Gaussian model is shown to result in a poor approximation. Second, the exact likelihood ratio is approximated by a piece-wise function. While the approximation can be done with very good accuracy, the bound must be evaluated numerically. 10 refs., 11 figs.
NITRO MUSK BOUND TO CARP HEMOGLOBIN ...
Nitroaromatic compounds including synthetic nitro musks are important raw materials and intermediates in the synthesis of explosives, dyes, and pesticides, pharmaceutical and personal care-products (PPCPs). The nitro musks such as musk xylene (MX) and musk ketone (MK) are extensively used as fragrance ingredients in PPCPs and other commercial toiletries. Identification and quantification of a bound 4-amino-MX (4-AMX) metabolite as well as a 2- amino-MK (2-AMK) metabolite were carried out by gas chromatography-mass spectrometry' (GC/MS), with selected ion monitoring (SIM) in both the electron ionization (ElMS) and electron capture (EC) negative ion chemical ionization (NICIMS) modes. Detection of 4-AMX and 2-AMK occurred after the cysteine adducts in carp hemoglobin, derived from the nitroso metabolites, were released by alkaline hydrolysis. The released metabolites were extracted into n-hexane. The extract was preconcentrated by evaporation, and analyzed by GC-SIM-MS. A comparison between the El and EC approaches was made. EC NICIMS detected both metabolites whereas only 4-AMX was detected by ElMS. The EC NICIMS approach exhibited fewer matrix responses and provided a lower detection limit. Quantitation in both approaches was based on internal standard and a calibration plot. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Q
Twisting, supercoiling and stretching in protein bound DNA
Lam, Pui-Man; Zhen, Yi
2018-04-01
We have calculated theoretical results for the torque and slope of the twisted DNA, with various proteins bound on it, using the Neukirch-Marko model, in the regime where plectonemes exist. We found that the torque in the protein bound DNA decreases compared to that in the bare DNA. This is caused by the decrease in the free energy g(f) , and hence the smaller persistence lengths, in the case of protein bound DNA. We hope our results will encourage experimental investigations of supercoiling in protein bound DNA, which can provide further tests of the Neukirch-Marko model.
Upper bounds on quantum uncertainty products and complexity measures
Energy Technology Data Exchange (ETDEWEB)
Guerrero, Angel; Sanchez-Moreno, Pablo; Dehesa, Jesus S. [Department of Atomic, Molecular and Nuclear Physics, University of Granada, Granada (Spain); Department of Applied Mathematics, University of Granada, Granada (Spain) and Institute Carlos I for Computational and Theoretical Physics, University of Granada, Granada (Spain); Department of Atomic, Molecular and Nuclear Physics, University of Granada, Granada (Spain); Institute Carlos I for Computational and Theoretical Physics, University of Granada, Granada (Spain)
2011-10-15
The position-momentum Shannon and Renyi uncertainty products of general quantum systems are shown to be bounded not only from below (through the known uncertainty relations), but also from above in terms of the Heisenberg-Kennard product . Moreover, the Cramer-Rao, Fisher-Shannon, and Lopez-Ruiz, Mancini, and Calbet shape measures of complexity (whose lower bounds have been recently found) are also bounded from above. The improvement of these bounds for systems subject to spherically symmetric potentials is also explicitly given. Finally, applications to hydrogenic and oscillator-like systems are done.
Classical Physics and the Bounds of Quantum Correlations.
Frustaglia, Diego; Baltanás, José P; Velázquez-Ahumada, María C; Fernández-Prieto, Armando; Lujambio, Aintzane; Losada, Vicente; Freire, Manuel J; Cabello, Adán
2016-06-24
A unifying principle explaining the numerical bounds of quantum correlations remains elusive, despite the efforts devoted to identifying it. Here, we show that these bounds are indeed not exclusive to quantum theory: for any abstract correlation scenario with compatible measurements, models based on classical waves produce probability distributions indistinguishable from those of quantum theory and, therefore, share the same bounds. We demonstrate this finding by implementing classical microwaves that propagate along meter-size transmission-line circuits and reproduce the probabilities of three emblematic quantum experiments. Our results show that the "quantum" bounds would also occur in a classical universe without quanta. The implications of this observation are discussed.
What Information Theory Says about Bounded Rational Best Response
Wolpert, David H.
2005-01-01
Probability Collectives (PC) provides the information-theoretic extension of conventional full-rationality game theory to bounded rational games. Here an explicit solution to the equations giving the bounded rationality equilibrium of a game is presented. Then PC is used to investigate games in which the players use bounded rational best-response strategies. Next it is shown that in the continuum-time limit, bounded rational best response games result in a variant of the replicator dynamics of evolutionary game theory. It is then shown that for team (shared-payoff) games, this variant of replicator dynamics is identical to Newton-Raphson iterative optimization of the shared utility function.
Particles in wall-bounded turbulent flows deposition, re-suspension and agglomeration
Pozorski, Jacek
2017-01-01
The book presents an up-to-date review of turbulent two-phase flows with the dispersed phase, with an emphasis on the dynamics in the near-wall region. New insights to the flow physics are provided by direct numerical simuation and by fine experimental techniques. Also included are models of particle dynamics in wall-bounded turbulent flows, and a description of particle surface interactions including muti-layer deposition and re-suspension.
UV-Visible Spectroscopy-Based Quantification of Unlabeled DNA Bound to Gold Nanoparticles.
Baldock, Brandi L; Hutchison, James E
2016-12-20
DNA-functionalized gold nanoparticles have been increasingly applied as sensitive and selective analytical probes and biosensors. The DNA ligands bound to a nanoparticle dictate its reactivity, making it essential to know the type and number of DNA strands bound to the nanoparticle surface. Existing methods used to determine the number of DNA strands per gold nanoparticle (AuNP) require that the sequences be fluorophore-labeled, which may affect the DNA surface coverage and reactivity of the nanoparticle and/or require specialized equipment and other fluorophore-containing reagents. We report a UV-visible-based method to conveniently and inexpensively determine the number of DNA strands attached to AuNPs of different core sizes. When this method is used in tandem with a fluorescence dye assay, it is possible to determine the ratio of two unlabeled sequences of different lengths bound to AuNPs. Two sizes of citrate-stabilized AuNPs (5 and 12 nm) were functionalized with mixtures of short (5 base) and long (32 base) disulfide-terminated DNA sequences, and the ratios of sequences bound to the AuNPs were determined using the new method. The long DNA sequence was present as a lower proportion of the ligand shell than in the ligand exchange mixture, suggesting it had a lower propensity to bind the AuNPs than the short DNA sequence. The ratio of DNA sequences bound to the AuNPs was not the same for the large and small AuNPs, which suggests that the radius of curvature had a significant influence on the assembly of DNA strands onto the AuNPs.
Nonlinear population dynamics in a bounded habitat.
Colombo, E H; Anteneodo, C
2018-02-27
A key issue in ecology is whether a population will survive long term or go extinct. This is the question we address in this paper for a population in a bounded habitat. We will restrict our study to the case of a single species in a one-dimensional habitat of length L. The evolution of the population density distribution ρ(x, t), where x is the position and t the time, is governed by elementary processes such as growth and dispersal, which, in standard models, are typically described by a constant per capita growth rate and normal diffusion, respectively. However, feedbacks in the regulatory mechanisms and external factors can produce density-dependent rates. Therefore, we consider a generalization of the standard evolution equation, which, after dimensional scaling and assuming large carrying capacity, becomes ∂ t ρ=∂ x (ρ ν-1 ∂ x ρ)+ρ μ , where μ,ν∈R. This equation is complemented by absorbing boundaries, mimicking adverse conditions outside the habitat. For this nonlinear problem, we obtain, analytically, exact expressions of the critical habitat size L c for population survival, as a function of the exponents and initial conditions. We find that depending on the values of the exponents (ν, μ), population survival can occur for either L > L c , L < L c or for any L. This generalizes the usual statement that L c represents the minimum habitat size. In addition, nonlinearities introduce dependence on the initial conditions, affecting L c . Copyright © 2018. Published by Elsevier Ltd.
Error bounds in MEG (Magnetoencephalography) multipole localization
Energy Technology Data Exchange (ETDEWEB)
Jerbi, K. (Karim); Mosher, J. C. (John C.); Baillet, S. (Sylvain); Leahy, R. M. (Richard M.)
2001-01-01
Magnetoencephalography (MEG) is a non-invasive method that enables the measurement of the magnetic field produced by neural current sources within the human brain. Unfortunately, MEG source estimation is a severely ill-posed inverse problem. The two major approaches used to tackle this problem are 'imaging' and 'model-based' methods. The first class of methods relies on a tessellation of the cortex, assigning an elemental current source to each area element and solving the linear inverse problem. Accurate tessellations lead to a highly underdetermined problem, and regularized linear methods lead to very smooth current distributions. An alternative approach widely used is a parametric representation of the neural source. Such model-based methods include the classic equivalent current dipole (ECD) and its multiple current dipole extension [1]. The definition of such models has been based on the assumption that the underlying sources are focal and small in number. An alternative approach reviewed in [4], [5] is to extend the parametric source representations within the model-based framework to allow for distributed sources. The multipolar expansion of the magnetic field about the centroid of a distributed source readily offers an elegant parametric model, which collapses to a dipole model in the limiting case and includes higher order terms in the case of a spatially extended source. While multipolar expansions have been applied to magnetocardiography (MCG) source modeling [2], their use in MEG has been restricted to simplified models [7]. The physiological interpretation of these higher-order components in non-intuitive, therefore limiting their application in this community (cf. [8]). In this study we investigate both the applicability of dipolar and multipolar models to cortical patches, and the accuracy with which we can locate these sources. We use a combination of Monte Carlo analyses and Cramer-Rao lower bounds (CRLBs), paralleling the work
Structure Biology of Membrane Bound Enzymes
Energy Technology Data Exchange (ETDEWEB)
Fu, Dax [Johns Hopkins Univ., Baltimore, MD (United States). School of Medicine. Dept. of Physiology
2016-11-30
The overall goal of the proposed research is to understand the membrane-associated active processes catalyzed by an alkane $\\square$-hydroxylase (AlkB) from eubacterium Pseudomonase oleovorans. AlkB performs oxygenation of unactivated hydrocarbons found in crude oils. The enzymatic reaction involves energy-demanding steps in the membrane with the uses of structurally unknown metal active sites featuring a diiron [FeFe] center. At present, a critical barrier to understanding the membrane-associated reaction mechanism is the lack of structural information. The structural biology efforts have been challenged by technical difficulties commonly encountered in crystallization and structural determination of membrane proteins. The specific aims of the current budget cycle are to crystalize AlkB and initiate X-ray analysis to set the stage for structural determination. The long-term goals of our structural biology efforts are to provide an atomic description of AlkB structure, and to uncover the mechanisms of selective modification of hydrocarbons. The structural information will help elucidating how the unactivated C-H bonds of saturated hydrocarbons are oxidized to initiate biodegradation and biotransformation processes. The knowledge gained will be fundamental to biotechnological applications to biofuel transformation of non-edible oil feedstock. Renewable biodiesel is a promising energy carry that can be used to reduce fossil fuel dependency. The proposed research capitalizes on prior BES-supported efforts on over-expression and purification of AlkB to explore the inner workings of a bioenergy-relevant membrane-bound enzyme.
DETERMINATION OF A BOUND MUSK XYLENE ...
Musk xylene (MX) is widely used as a fragrance ingredient in commercial toiletries. Identification and quantification of a bound 4-amino-MX (AMX) metabolite was carried out by gas chromatography-mass spectrometry (GC/MS), with selected ion monitoring (SIM). Detection of AMX occurred after the cysteine adducts in carp hemoglobin, derived from the nitroso metabolite, were released by alkaline hydrolysis. The released AMX metabolite was extracted into n-hexane. The extract was preconcentrated by evaporation, and analyzed by GC-SIM-MS. The concentration of AMX metabolite was found to range from 6.0 to 30.6 ng/g in the carp Hb, collected from the Las Vegas Wash and Lake Mead, Nevada areas. The presence of an AMX metabolite in the carp Hb was confirmed when similar mass spectral features and the same retention time of the AMX metabolite were obtained for both standard AMX and carp Hb extract solutions. In the non-hydrolyzed and reagent blank extracts, the AMX metabolite was not detected. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers,
Group IV nanocrystals with ion-exchangeable surface ligands and methods of making the same
Energy Technology Data Exchange (ETDEWEB)
Wheeler, Lance M.; Nichols, Asa W.; Chernomordik, Boris D.; Anderson, Nicholas C.; Beard, Matthew C.; Neale, Nathan R.
2018-01-09
Methods are described that include reacting a starting nanocrystal that includes a starting nanocrystal core and a covalently bound surface species to create an ion-exchangeable (IE) nanocrystal that includes a surface charge and a first ion-exchangeable (IE) surface ligand ionically bound to the surface charge, where the starting nanocrystal core includes a group IV element.
Structure and orientation of dynorphin bound to lipid bilayers by 13C solid-state NMR
Uezono, Takiko; Toraya, Shuichi; Obata, Maki; Nishimura, Katsuyuki; Tuzi, Satoru; Saitô, Hazime; Naito, Akira
2005-07-01
Secondary structure and orientation of dynorphin bound to dimyristoylphosphatidylcholine (DMPC) bilayer were investigated by solid-state 13C NMR spectroscopy. For this purpose, 13C NMR spectra of the site-specifically 13C-labeled dynorphin were measured in the membrane-bound state under static, magic angle spinning (MAS), and slow MAS conditions. In the static experiment, magnetically oriented vesicle system (MOVS) induced by dynorphin was successfully used to investigate the orientation of dynorphin bound to the lipid bilayers. It was found that dynorphin adopts an α-helical structure in the N-terminus from Gly 2 to Leu 5 by analyses of the isotropic chemical shifts obtained from the MAS experiments. In contrast, it adopts disordered conformations from the center to the C-terminus and is located on the membrane surface. The static 13C NMR spectra indicated that MOVS-bound dynorphin was oriented to the magnetic field and rotated rapidly about the bilayer normal. Subsequently, we analyzed the 13C chemical shift tensors of carbonyl carbons in the peptide backbone by considering the rotational motion of the N-terminal α-helix. It was revealed that the N-terminal α-helix is inserted into the membrane with the tilt angle of 21° to the bilayer normal. This structure suggests a possibility that dynorphin interacts with the extracellular loop II of the κ-receptor through a helix-helix interaction.
Linking Thermodynamics to Pollutant Reduction Kinetics by Fe2+Bound to Iron Oxides.
Stewart, Sydney M; Hofstetter, Thomas B; Joshi, Prachi; Gorski, Christopher A
2018-03-29
Numerous studies have reported that pollutant reduction rates by ferrous iron (Fe 2+ ) are substantially enhanced in the presence of an iron (oxyhydr)oxide mineral. Developing a thermodynamic framework to explain this phenomenon has been historically difficult due to challenges in quantifying reduction potential ( E H ) values for oxide-bound Fe 2+ species. Recently, our group demonstrated that E H values for hematite- and goethite-bound Fe 2+ can be accurately calculated using Gibbs free energy of formation values. Here, we tested if calculated E H values for oxide-bound Fe 2+ could be used to develop a free energy relationship capable of describing variations in reduction rate constants of of substituted nitrobenzenes, a class of model pollutants that contain reducible aromatic nitro groups, using data collected here and compiled from the literature. All the data could be described by a single linear relationship between the logarithms of the surface-area-normalized rate constant ( k SA ) values and E H and pH values [log( k SA ) = - E H /0.059V - pH + 3.42]. This framework provides mechanistic insights into how the thermodynamic favorability of electron transfer from oxide-bound Fe 2+ relates to redox reaction kinetics.
Solving the minimum flow problem with interval bounds and flows
Indian Academy of Sciences (India)
... with crisp data. In this paper, the idea of Ghiyasvand was extended for solving the minimum ﬂow problem with interval-valued lower, upper bounds and ﬂows. This problem can be solved using two minimum ﬂow problems with crisp data. Then, this result is extended to networks with fuzzy lower, upper bounds and ﬂows.
Parity lifetime of bound states in a proximitized semiconductor nanowire
DEFF Research Database (Denmark)
Higginbotham, Andrew Patrick; Albrecht, Sven Marian; Kirsanskas, Gediminas
2015-01-01
superconductor layer, yielding an isolated, proximitized nanowire segment. We identify Andreev-like bound states in the semiconductor via bias spectroscopy, determine the characteristic temperatures and magnetic fields for quasiparticle excitations, and extract a parity lifetime (poisoning time) of the bound...
Bounds of Certain Dynamic Inequalities on Time Scales
Directory of Open Access Journals (Sweden)
Deepak B. Pachpatte
2014-10-01
Full Text Available In this paper we study explicit bounds of certain dynamic integral inequalities on time scales. These estimates give the bounds on unknown functions which can be used in studying the qualitative aspects of certain dynamic equations. Using these inequalities we prove the uniqueness of some partial integro-differential equations on time scales.
Inequalities involving upper bounds for certain matrix operators
Indian Academy of Sciences (India)
Inequalities involving upper bounds for certain matrix operators. R LASHKARIPOUR and D ... Inequality; norm; summability matrix; Hausdorff matrix; Hilbert matrix; weighted sequence space; Lorentz ...... [10] Pecari J, Peric I and Roki R, On bounds for weighted norms for matrices and integral operators, Linear Algebra and ...
Higgs interchange and bound states of superheavy fermions
Indian Academy of Sciences (India)
Hypothetical superheavy fourth-generation fermions with a very small coupling with the rest of the Standard Model can give rise to long enough lived bound states. The production and the detection of these bound states would be experimentally feasible at the LHC. Extending, in the present study, the analysis of other ...
Bounds for Tail Probabilities of the Sample Variance
Directory of Open Access Journals (Sweden)
V. Bentkus
2009-01-01
Full Text Available We provide bounds for tail probabilities of the sample variance. The bounds are expressed in terms of Hoeffding functions and are the sharpest known. They are designed having in mind applications in auditing as well as in processing data related to environment.
On longest edge division in simplicial branch and bound
Herrera, J.F.R.; Casado, L.G.; Hendrix, E.M.T.
2014-01-01
Simplicial partitions are suitable to divide a bounded area in branch and bound. In the iterative refinement process, a popular strategy is to divide simplices by their longest edge, thus avoiding needle-shaped simplices. A range of possibilities arises when the number of longest edges in a simplex
New upper bounds for kissing numbers from semidefinite programming
C. Bachoc; F. Vallentin (Frank)
2008-01-01
htmlabstractRecently A. Schrijver derived new upper bounds for binary codes using semidefinite programming. In this paper we adapt this approach to codes on the unit sphere and we compute new upper bounds for the kissing number in several dimensions. In particular our computations give the (known)
New upper bounds for kissing numbers from semidefinite programming
C. Bachoc; F. Vallentin (Frank)
2006-01-01
htmlabstractRecently A. Schrijver derived new upper bounds for binary codes using semidefinite programming. In this paper we adapt this approach to codes on the unit sphere and we compute new upper bounds for the kissing number in several dimensions. In particular our computations give the (known)
Bound residues of 14C-chlorotoluron in soil
International Nuclear Information System (INIS)
Chen Zuyi; Shi Ying; Huang Shile
1992-07-01
Dynamics of bound residues of 14 C-chlorotoluron, distribution of the bound residues in the components of humus, and their absorption by step-crop (rice) were investigated in paddy soil and black soil under simulated aerobic and anaerobic conditions respectively. The results show that: (1) The bound residues of 14 C-chlorotoluron in soil were very considerable and increasing with the incubation time. The organic substance and humidity contained in the soil affected the bound residues remarkably. The bound residues in black soil with more organic substance and clay particles were higher than those in paddy soil, and under anaerobic conditions were higher than under aerobic conditions. (2) Bound residues of 14 C-chlorotoluron mainly bound with the components of soil humus, the distribution of which was in the order of humin>humic acid>fulvic acid. (3) Bound residues of 14 C-chlorotoluron in soils could be absorbed by step-crop (rice) and moved to the upper part, that would cause chemical injury, chlorosis and necrosis for the leaf tip
Entropy Bounds for Constrained Two-Dimensional Fields
DEFF Research Database (Denmark)
Forchhammer, Søren Otto; Justesen, Jørn
1999-01-01
The maximum entropy and thereby the capacity of 2-D fields given by certain constraints on configurations are considered. Upper and lower bounds are derived.......The maximum entropy and thereby the capacity of 2-D fields given by certain constraints on configurations are considered. Upper and lower bounds are derived....
Upper bounds for reversible circuits based on Young subgroups
DEFF Research Database (Denmark)
Abdessaied, Nabila; Soeken, Mathias; Thomsen, Michael Kirkedal
2014-01-01
We present tighter upper bounds on the number of Toffoli gates needed in reversible circuits. Both multiple controlled Toffoli gates and mixed polarity Toffoli gates have been considered for this purpose. The calculation of the bounds is based on a synthesis approach based on Young subgroups...
Models and Techniques for Proving Data Structure Lower Bounds
DEFF Research Database (Denmark)
Larsen, Kasper Green
In this dissertation, we present a number of new techniques and tools for proving lower bounds on the operational time of data structures. These techniques provide new lines of attack for proving lower bounds in both the cell probe model, the group model, the pointer machine model and the I....../O-model. In all cases, we push the frontiers further by proving lower bounds higher than what could possibly be proved using previously known techniques. For the cell probe model, our results have the following consequences: The rst (lg n) query time lower bound for linear space static data structures...... bound of tutq = (lgd1 n). For ball range searching, we get a lower bound of tutq = (n11=d). The highest previous lower bound proved in the group model does not exceed ((lg n= lg lg n)2) on the maximum of tu and tq. Finally, we present a new technique for proving lower bounds...
The question of an upper bound on entropy
International Nuclear Information System (INIS)
Qadir, A.
1982-08-01
We discuss the possibility, and significance, of an upper bound on entropy in the light of the arguments of Bekenstein and Unruh and Wald. We obtain a stricter bound than Bekenstein does, and point out some limitations with regard to its significance. (author)
Improved Space Bounds for Cache-Oblivious Range Reporting
DEFF Research Database (Denmark)
Afshani, Peyman; Zeh, Norbert
2011-01-01
We provide improved bounds on the size of cacheoblivious range reporting data structures that achieve the optimal query bound of O(logB N + K/B) block transfers. Our first main result is an O(N √ logN log logN)-space data structure that achieves this query bound for 3-d dominance reporting and 2-d...... three-sided range reporting. No cache-oblivious o(N log N/ log logN)-space data structure for these problems was known before, even when allowing a query bound of O(logO(1) 2 N + K/B) block transfers.1 Our result also implies improved space bounds for general 2-d and 3-d orthogonal range reporting. Our...... second main result shows that any cache-oblivious 2-d three-sided range reporting data structure with the optimal query bound has to use Ω(N logε N) space, thereby improving on a recent lower bound for the same problem. Using known transformations, the lower bound extends to 3-d dominance reporting and 3...
Holographic bounds on the UV cutoff scale in inflationary cosmology
DEFF Research Database (Denmark)
Keski-Vakkuri, Esko; Sloth, Martin Snoager
2003-01-01
We discuss how holographic bounds can be applied to the quantum fluctuations of the inflaton. In general the holographic principle will lead to a bound on the UV cutoff scale of the effective theory of inflation, but it will depend on the coarse-graining prescription involved in calculating...
Optimal Two Parameter Bounds for the Seiffert Mean
Directory of Open Access Journals (Sweden)
Hui Sun
2013-01-01
Full Text Available We obtain sharp bounds for the Seiffert mean in terms of a two parameter family of means. Our results generalize and extend the recent bounds presented in the Journal of Inequalities and Applications (2012 and Abstract and Applied Analysis (2012.
Quasi-bound states, resonance tunnelling, and tunnelling times ...
Indian Academy of Sciences (India)
We compare the behaviour of the magnitude of wave func- tions of quasi-bound states with those for bound states and with the above-barrier state wave function. We deduce a Breit–Wigner-type resonance formula which neatly describes the variation of transmission coefficient as a function of energy at below-barrier ...
Towards an abstract parallel branch and bound machine
A. de Bruin (Arie); G.A.P. Kindervater (Gerard); H.W.J.M. Trienekens
1995-01-01
textabstractMany (parallel) branch and bound algorithms look very different from each other at first glance. They exploit, however, the same underlying computational model. This phenomenon can be used to define branch and bound algorithms in terms of a set of basic rules that are applied in a
On bounding the bandwidth of graphs with symmetry
van Dam, E.R.; Sotirov, R.
2015-01-01
We derive a new lower bound for the bandwidth of a graph that is based on a new lower bound for the min-cut problem. Our new semidefinite programming relaxation of the min-cut problem is obtained by strengthening the known semidefinite programming relaxation for the quadratic assignment problem (or
Dark-matter bound states from Feynman diagrams
Petraki, K.; Postma, M.; Wiechers, M.
2015-01-01
If dark matter couples directly to a light force mediator, then it may form bound states in the early universe and in the non-relativistic environment of haloes today. In this work, we establish a field-theoretic framework for the computation of bound-state formation cross-sections, de-excitation
A branch-and-bound methodology within algebraic modelling systems
Bisschop, J.J.; Heerink, J.B.J.; Kloosterman, G.
1998-01-01
Through the use of application-specific branch-and-bound directives it is possible to find solutions to combinatorial models that would otherwise be difficult or impossible to find by just using generic branch-and-bound techniques within the framework of mathematical programming. {\\sc Minto} is an
A tail bound for read-k families of functions
Czech Academy of Sciences Publication Activity Database
Gavinsky, Dmitry; Lovett, S.; Saks, M.; Srinivasan, S.
2015-01-01
Roč. 47, č. 1 (2015), s. 99-108 ISSN 1042-9832 Institutional support: RVO:67985840 Keywords : tail bound * deviation bound * random variables Subject RIV: BA - General Mathematics Impact factor: 1.011, year: 2015 http://onlinelibrary.wiley.com/doi/10.1002/rsa.20532/abstract
On parallel Branch and Bound frameworks for Global Optimization
Herrera, Juan F.R.; Salmerón, José M.G.; Hendrix, Eligius M.T.; Asenjo, Rafael; Casado, Leocadio G.
2017-01-01
Branch and Bound (B&B) algorithms are known to exhibit an irregularity of the search tree. Therefore, developing a parallel approach for this kind of algorithms is a challenge. The efficiency of a B&B algorithm depends on the chosen Branching, Bounding, Selection, Rejection, and Termination
Transient response in granular quasi-two-dimensional bounded heap flow
Xiao, Hongyi; Ottino, Julio M.; Lueptow, Richard M.; Umbanhowar, Paul B.
2017-10-01
We study the transition between steady flows of noncohesive granular materials in quasi-two-dimensional bounded heaps by suddenly changing the feed rate. In both experiments and simulations, the primary feature of the transition is a wedge of flowing particles that propagates downstream over the rising free surface with a wedge front velocity inversely proportional to the square root of time. An additional longer duration transient process continues after the wedge front reaches the downstream wall. The entire transition is well modeled as a moving boundary problem with a diffusionlike equation derived from local mass balance and a local relation between the flux and the surface slope.
Bounds on the dissipation in the Lorenz system
International Nuclear Information System (INIS)
Petrelis, Francois; Petrelis, Nicolas
2004-01-01
In this Letter we find an upper bound on the time-averaged dissipation in the Lorenz system (L. s.) [J. Atmos. Sci. 20 (1963) 244]. Whereas bounding theories were developed and applied to systems described by partial differential equations displaying turbulent behavior, we develop a method similar to the 'background method' [Phys. Rev. E 49 (1994) 4087; Phys. Rev. E 53 (1996) 5957; Phys. Rev. E 51 (1995) 3192; Phys. Plasmas 10 (2003) 4314; Phys. Plasmas 10 (2003) 4324] and apply it to the L. s., which consists of three first-order ordinary differential equations. The bound and the bounding field are explicitly calculated and compared to the numerically computed solutions of the system. For large values of the control parameter, the bound and the time-averaged dissipation differ by less than three percent. We then apply our method to another positive quadratic form defined for the solutions of the L. s
Proximity effect tunneling into virtual bound state alloys
International Nuclear Information System (INIS)
Tang, I.M.; Roongkkeadsakoon, S.
1984-01-01
The effects of a narrow virtual bound state formed by transition metal impurities dissolved in the normal layer of a superconducting proximity effect sandwich are studied. Using standard renormalization techniques, we obtain the changes in the transition temperatures and the jumps in the specific heat at T/sub c/ as a function of the thickness of the normal layer, of the widths of the virtual bound states, and of the impurity concentrations. It is seen that narrow virtual bound states lead to decrease in the transition temperatures, while broad virtual bound states do not. It if further seen that the narrow virtual bound state causes the reduced specific heat jump at T/sub c/ to deviate from the BCS behavior expected of the pure sandwich
Synergism between soluble and dietary fiber bound antioxidants.
Çelik, Ecem Evrim; Gökmen, Vural; Skibsted, Leif H
2015-03-04
This study investigates the synergism between antioxidants bound to dietary fibers (DF) of grains and soluble antioxidants of highly consumed beverages or their pure antioxidants. The interaction between insoluble fractions of grains containing bound antioxidants and soluble antioxidants was investigated using (i) a liposome-based system by measuring the lag phase before the onset of oxidation and (ii) an ESR-based system by measuring the reduction percentage of Fremy's salt radical. In both procedures, antioxidant capacities of DF-bound and soluble antioxidants were measured as well as their combinations, which were prepared at different ratios. The simple addition effects of DF-bound and soluble antioxidants were compared with measured values. The results revealed a clear synergism for almost all combinations in both liposome- and ESR-based systems. The synergism observed in DF-bound-soluble antioxidant system paints a promising picture considering the role of fiber in human gastrointestinal (GI) tract health.
Bounds of memory strength for power-law series
Guo, Fangjian; Yang, Dan; Yang, Zimo; Zhao, Zhi-Dan; Zhou, Tao
2017-05-01
Many time series produced by complex systems are empirically found to follow power-law distributions with different exponents α . By permuting the independently drawn samples from a power-law distribution, we present nontrivial bounds on the memory strength (first-order autocorrelation) as a function of α , which are markedly different from the ordinary ±1 bounds for Gaussian or uniform distributions. When 1 3 , the upper bound remains +1 while the lower bound descends below 0. Theoretical bounds agree well with numerical simulations. Based on the posts on Twitter, ratings of MovieLens, calling records of the mobile operator Orange, and the browsing behavior of Taobao, we find that empirical power-law-distributed data produced by human activities obey such constraints. The present findings explain some observed constraints in bursty time series and scale-free networks and challenge the validity of measures such as autocorrelation and assortativity coefficient in heterogeneous systems.
Evacuation of Bed-bound Patients-STEPS Simulations
DEFF Research Database (Denmark)
Madsen, Anne; Dederichs, Anne Simone
2016-01-01
Fires in hospitals occur, and evacuation of bed-bound patients might be necessary in case of emergency. The current study concerns the evacuation of bed-bound patients from a fire section in a hospital using hospital porters. The simulations are performed using the STEPS program. The aim...... of the study is to investigate the evacuation time of bed-bound hospital patients using different walking speeds from the literature, and the influence of the number of hospital porters on the total evacuation times of bed-bound patients. Different scenarios were carried out with varying staff......-to-patient ratios that simulate the horizontal evacuation of 40 bed-bound patients into a different fire section. It was found that the staff-to-patient-ratio affects the total evacuation times. However, the total evacuation times do not decrease linearly and a saturation effect is seen at a staff-to-patient ratio...
Bounds of memory strength for power-law series.
Guo, Fangjian; Yang, Dan; Yang, Zimo; Zhao, Zhi-Dan; Zhou, Tao
2017-05-01
Many time series produced by complex systems are empirically found to follow power-law distributions with different exponents α. By permuting the independently drawn samples from a power-law distribution, we present nontrivial bounds on the memory strength (first-order autocorrelation) as a function of α, which are markedly different from the ordinary ±1 bounds for Gaussian or uniform distributions. When 13, the upper bound remains +1 while the lower bound descends below 0. Theoretical bounds agree well with numerical simulations. Based on the posts on Twitter, ratings of MovieLens, calling records of the mobile operator Orange, and the browsing behavior of Taobao, we find that empirical power-law-distributed data produced by human activities obey such constraints. The present findings explain some observed constraints in bursty time series and scale-free networks and challenge the validity of measures such as autocorrelation and assortativity coefficient in heterogeneous systems.
Amos-type bounds for modified Bessel function ratios☆
Hornik, Kurt; Grün, Bettina
2013-01-01
We systematically investigate lower and upper bounds for the modified Bessel function ratio Rν=Iν+1/Iν by functions of the form Gα,β(t)=t/(α+t2+β2) in case Rν is positive for all t>0, or equivalently, where ν≥−1 or ν is a negative integer. For ν≥−1, we give an explicit description of the set of lower bounds and show that it has a greatest element. We also characterize the set of upper bounds and its minimal elements. If ν≥−1/2, the minimal elements are tangent to Rν in exactly one point 0≤t≤∞, and have Rν as their lower envelope. We also provide a new family of explicitly computable upper bounds. Finally, if ν is a negative integer, we explicitly describe the sets of lower and upper bounds, and give their greatest and least elements, respectively. PMID:24926105
Amos-type bounds for modified Bessel function ratios.
Hornik, Kurt; Grün, Bettina
2013-12-01
We systematically investigate lower and upper bounds for the modified Bessel function ratio [Formula: see text] by functions of the form [Formula: see text] in case [Formula: see text] is positive for all [Formula: see text], or equivalently, where [Formula: see text] or [Formula: see text] is a negative integer. For [Formula: see text], we give an explicit description of the set of lower bounds and show that it has a greatest element. We also characterize the set of upper bounds and its minimal elements. If [Formula: see text], the minimal elements are tangent to [Formula: see text] in exactly one point [Formula: see text], and have [Formula: see text] as their lower envelope. We also provide a new family of explicitly computable upper bounds. Finally, if [Formula: see text] is a negative integer, we explicitly describe the sets of lower and upper bounds, and give their greatest and least elements, respectively.
Viscosity bound violation in holographic solids and the viscoelastic response
Energy Technology Data Exchange (ETDEWEB)
Alberte, Lasma [Abdus Salam International Centre for Theoretical Physics (ICTP),Strada Costiera 11, 34151, Trieste (Italy); Baggioli, Matteo [Institut de Física d’Altes Energies (IFAE),The Barcelona Institute of Science and Technology (BIST),Campus UAB, 08193 Bellaterra, Barcelona (Spain); Department of Physics, Institute for Condensed Matter Theory, University of Illinois,1110 W. Green Street, Urbana, IL 61801 (United States); Pujolàs, Oriol [Institut de Física d’Altes Energies (IFAE),The Barcelona Institute of Science and Technology (BIST),Campus UAB, 08193 Bellaterra, Barcelona (Spain)
2016-07-14
We argue that the Kovtun-Son-Starinets (KSS) lower bound on the viscosity to entropy density ratio holds in fluid systems but is violated in solid materials with a non-zero shear elastic modulus. We construct explicit examples of this by applying the standard gauge/gravity duality methods to massive gravity and show that the KSS bound is clearly violated in black brane solutions whenever the massive gravity theories are of solid type. We argue that the physical reason for the bound violation relies on the viscoelastic nature of the mechanical response in these materials. We speculate on whether any real-world materials can violate the bound and discuss a possible generalization of the bound that involves the ratio of the shear elastic modulus to the pressure.
Steric Pressure among Membrane-Bound Polymers Opposes Lipid Phase Separation.
Imam, Zachary I; Kenyon, Laura E; Carrillo, Adelita; Espinoza, Isai; Nagib, Fatema; Stachowiak, Jeanne C
2016-04-19
Lipid rafts are thought to be key organizers of membrane-protein complexes in cells. Many proteins that interact with rafts have bulky polymeric components such as intrinsically disordered protein domains and polysaccharide chains. Therefore, understanding the interaction between membrane domains and membrane-bound polymers provides insights into the roles rafts play in cells. Multiple studies have demonstrated that high concentrations of membrane-bound polymeric domains create significant lateral steric pressure at membrane surfaces. Furthermore, our recent work has shown that lateral steric pressure at membrane surfaces opposes the assembly of membrane domains. Building on these findings, here we report that membrane-bound polymers are potent suppressors of membrane phase separation, which can destabilize lipid domains with substantially greater efficiency than globular domains such as membrane-bound proteins. Specifically, we created giant vesicles with a ternary lipid composition, which separated into coexisting liquid ordered and disordered phases. Lipids with saturated tails and poly(ethylene glycol) (PEG) chains conjugated to their head groups were included at increasing molar concentrations. When these lipids were sparse on the membrane surface they partitioned to the liquid ordered phase. However, as they became more concentrated, the fraction of GUVs that were phase-separated decreased dramatically, ultimately yielding a population of homogeneous membrane vesicles. Experiments and physical modeling using compositions of increasing PEG molecular weight and lipid miscibility phase transition temperature demonstrate that longer polymers are the most efficient suppressors of membrane phase separation when the energetic barrier to lipid mixing is low. In contrast, as the miscibility transition temperature increases, longer polymers are more readily driven out of domains by the increased steric pressure. Therefore, the concentration of shorter polymers required
Bounds on Gromov hyperbolicity constant in graphs
Indian Academy of Sciences (India)
is a topic of recent and increasing interest in graph theory; see, for instance [3–5, 8–10,. 15–17, 18–20, 22, 23, 25–27]. The theory ..... the Laplace matrix μ∗, we have δ(G) ≤ n(μ∗ − d0) μ∗ . Proof. ..... [27] Tourís E, Graphs and Gromov hyperbolicity of non-constant negatively curved surfaces,. J. Math. Anal. Appl. 380 (2011) ...
International Nuclear Information System (INIS)
Kim, Yongbae; Olivi, Luisa; Cheong, Jae Hoon; Maertens, Alex; Bressler, Joseph P.
2007-01-01
Aluminum and other trivalent metals were shown to stimulate uptake of transferrin bound iron and nontransferrin bound iron in erytholeukemia and hepatoma cells. Because of the association between aluminum and Alzheimer's Disease, and findings of higher levels of iron in Alzheimer's disease brains, the effects of aluminum on iron homeostasis were examined in a human glial cell line. Aluminum stimulated dose- and time-dependent uptake of nontransferrin bound iron and iron bound to transferrin. A transporter was likely involved in the uptake of nontransferrin iron because uptake reached saturation, was temperature-dependent, and attenuated by inhibitors of protein synthesis. Interestingly, the effects of aluminum were not blocked by inhibitors of RNA synthesis. Aluminum also decreased the amount of iron bound to ferritin though it did not affect levels of divalent metal transporter 1. These results suggest that aluminum disrupts iron homeostasis in Brain by several mechanisms including the transferrin receptor, a nontransferrin iron transporter, and ferritin
He, Lu-lu; Song, Jian-zhong; Yu, Chi-ling; Peng, Ping-an
2008-12-01
Free and bound residues are the main form of organochlorine pesticides (OCPs) in soils/sediments. Four surface soil/sediments from the Pearl River Delta, China, were selected to characterize free and bound OCPs in different fractions of organic matters in the samples through alka-extraction, HCl/HF demineralization and organic solvent extraction. Total OCPs concentrations of samples were 20.96-134.22 microg x kg(-1), total HCHs concentrations were 5.66-22.87 microg x kg(-1), and total DDTs concentrations were 1.51-11.70 microg x kg(-1). beta-HCH, heptachlor, aldrin, endrin, endosulfan sulfate and methoxychlor were the dominate compounds which took 53.56%-77.26% of total OCPs. Concentrations of free OCPs were 8.46-88.45 microg x kg(-1) and took 40.37%-65.90% of total OCPs while concentrations of bound OCPs were 11.46-45.77 microg x kg(-1) and took 34.10%-59.63% of total OCPs. Most of bound OCPs were in the humic acid and humin fractions of the samples which shows the significantly occurrence of bound OCPs in environment. Distributions of free DDTs and HCHs showed that there were no fresh HCHs poured into these samples but there were fresh DDTs poured into some of the samples. The distribution of OCPs in these two fractions were associated with the organic C content of the fractions, and 94.78%-97.48% of bound OCPs were in humin fraction which took 57.71%-80.55% of total organic C in the samples. Environmental risk estimate showed that some free OCPs such as gamma-HCH, aldrin, endrin and DDTs may have risk to environment and total of free and bound concentration of each compound were 1-30 times higher than free concentration of each compound. Therefore bound OCPs should be considered while making the environmental risk estimate and establishing environmental criteria.
Two-phonon bound states in imperfect crystals
International Nuclear Information System (INIS)
Behera, S.N.; Samsur, Sk.
1980-01-01
The question of the occurrence of two-phonon bound states in imperfect crystals is investigated. It is shown that the anharmonicity mediated two-phonon bound state which is present in perfect crystals gets modified due to the presence of impurities. Moreover, the possibility of the occurrence of a purely impurity mediated two-phonon bound state is demonstrated. The bound state frequencies are calculated using the simple Einstein oscillator model for the host phonons. The two-phonon density of states for the imperfect crystal thus obtained has peaks at the combination and difference frequencies of two host phonons besides the peaks at the bound state frequencies. For a perfect crystal the theory predicts a single peak at the two-phonon bound state frequency in conformity with experimental observations and other theoretical calculations. Experimental data on the two-phonon infrared absorption and Raman scattering from mixed crystals of Gasub(1-c)Alsub(c)P and Gesub(1-c)Sisub(c) are analysed to provide evidence in support of impurity-mediated two-phonon bound states. The relevance of the zero frequency (difference spectrum) peak to the central peak, observed in structural phase transitions, is conjectured. (author)
Entropy bounds and the second law for black holes
International Nuclear Information System (INIS)
Bekenstein, J.D.
1983-01-01
A counterexample to the entropy bound proposed by Unruh and Wald and by Page is described. The bound states that the entropy S of any system with energy E and volume V cannot exceed the entropy of an equal volume and energy of unconfined thermal radiation. The bound is found to be violated by thermal field systems whose various dimensions differ by an order of magnitude or more, the violation occurring at intermediate energies. Unruh and Wald used the bound in an argument establishing the validity of the generalized second law when a box containing some entropy is lowered to near a black hole, then opened, and withdrawn open. If the box is thin in one direction, the failure of the bound for its contents makes it appear that a violation of the second law is possible. We show that, in fact, for a thin box the buoyancy effects on which Unruh and Wald's argument relies cancel out. As a result, the second law is fulfilled despite the failure of the bound. It appears from the second law that the bound must nevertheless hold when applied to box plus contents, but a direct proof of this is still lacking. We also consider the alternative entropy bound S< or =2πER/hc (2R is the largest dimension of the system) proposed earlier. For field systems it is shown to fail at very low energies, but to be valid for complete systems (i.e., box plus confined fields). Further, we show S< or =22[ER/hc is a necessary condition for fulfillment of the second law when a thin system is dropped into a black hole (even in the face of buoyancy) in the sense that if the bound failed, the law would be violated
Comment on ``Weakly bound states of the He-He-Ca triatomic system''
López-Durán, D. David; González-Lezana, T.; Delgado-Barrio, G.; Villarreal, P.; Gianturco, F. A.
2012-07-01
We discuss the computational results on the energetics and features of the bound states of one and two He atoms attached to a Ca atom, which have been presented by Gou and Li in a recently published paper in Phys. Rev. APLRAAN1050-294710.1103/PhysRevA.85.012510 85, 012510 (2012). We show that, given their choice for the interaction potential-energy surface, the energy they found for the three-particle complex's ground state must be incorrect. We also point out that a large number of their excited states for the same system do not really exist since they are located above either of the two-atom components' bound-state energies.
Hadamard States for the Klein-Gordon Equation on Lorentzian Manifolds of Bounded Geometry
Gérard, Christian; Oulghazi, Omar; Wrochna, Michał
2017-06-01
We consider the Klein-Gordon equation on a class of Lorentzian manifolds with Cauchy surface of bounded geometry, which is shown to include examples such as exterior Kerr, Kerr-de Sitter spacetime and the maximal globally hyperbolic extension of the Kerr outer region. In this setup, we give an approximate diagonalization and a microlocal decomposition of the Cauchy evolution using a time-dependent version of the pseudodifferential calculus on Riemannian manifolds of bounded geometry. We apply this result to construct all pure regular Hadamard states (and associated Feynman inverses), where regular refers to the state's two-point function having Cauchy data given by pseudodifferential operators. This allows us to conclude that there is a one-parameter family of elliptic pseudodifferential operators that encodes both the choice of (pure, regular) Hadamard state and the underlying spacetime metric.
Mass spectrum bound state systems with relativistic corrections
Energy Technology Data Exchange (ETDEWEB)
Dineykhan, M; Zhaugasheva, S A [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna (Russian Federation); Toinbaeva, N Sh; Jakhanshir, A [al-Farabi Kazak National University, 480012 Almaty (Kazakhstan)
2009-07-28
Based on the investigation of the asymptotic behaviour of the polarization loop function for charged n scalar particles in an external gauge field, we determine the interaction Hamiltonian including relativistic corrections. The mass spectrum of the bound state is analytically derived. The mechanism for arising of the constituent mass of the relativistic bound-state forming particles is explained. The mass and the constituent mass of the two-, three- and n-body relativistic bound states are calculated taking into account relativistic corrections. The corrections arising due to the one- and two-loop electron polarization to the energy spectrum of muonic hydrogen with orbital and radial excitations are calculated.
Bounds on charge and heat diffusivities in momentum dissipating holography
Energy Technology Data Exchange (ETDEWEB)
Amoretti, Andrea [Dipartimento di Fisica, Università di Genova,via Dodecaneso 33, I-16146, Genova (Italy); INFN - Sezione di Genova,via Dodecaneso 33, I-16146, Genova (Italy); Lorentz Institute for Theoretical Physics,Niels Bohrweg 2, Leiden NL-2333 CA (Netherlands); Braggio, Alessandro [INFN - Sezione di Genova,via Dodecaneso 33, I-16146, Genova (Italy); CNR-SPIN,Via Dodecaneso 33, 16146, Genova (Italy); Magnoli, Nicodemo [Dipartimento di Fisica, Università di Genova,via Dodecaneso 33, I-16146, Genova (Italy); INFN - Sezione di Genova,via Dodecaneso 33, I-16146, Genova (Italy); Musso, Daniele [Abdus Salam International Centre for Theoretical Physics (ICTP),Strada Costiera 11, I-34151 Trieste (Italy)
2015-07-20
Inspired by a recently conjectured universal bound for thermo-electric diffusion constants in quantum critical, strongly coupled systems and relying on holographic analytical computations, we investigate the possibility of formulating Planckian bounds in different holographic models featuring momentum dissipation. For a certain family of solutions to a simple massive gravity dilaton model at zero charge density we find linear in temperature resistivity and entropy density alongside a constant electric susceptibility. In addition we explicitly find that the sum of the thermo-electric diffusion constants is bounded.
Bounded stabilisation of stochastic port-Hamiltonian systems
Satoh, Satoshi; Saeki, Masami
2014-08-01
This paper proposes a stochastic bounded stabilisation method for a class of stochastic port-Hamiltonian systems. Both full-actuated and underactuated mechanical systems in the presence of noise are considered in this class. The proposed method gives conditions for the controller gain and design parameters under which the state remains bounded in probability. The bounded region and achieving probability are both assignable, and a stochastic Lyapunov function is explicitly provided based on a Hamiltonian structure. Although many conventional stabilisation methods assume that the noise vanishes at the origin, the proposed method is applicable to systems under persistent disturbances.
Experimental observation of optical bound states in the continuum.
Plotnik, Yonatan; Peleg, Or; Dreisow, Felix; Heinrich, Matthias; Nolte, Stefan; Szameit, Alexander; Segev, Mordechai
2011-10-28
We present the experimental observation of bound states in the continuum. Our experiments are carried out in an optical waveguide array structure, where the bound state (guided mode) is decoupled from the continuum by virtue of symmetry only. We demonstrate that breaking the symmetry of the system couples this special bound state to continuum states, leading to radiative losses. These experiments demonstrate ideas initially proposed by von Neumann and Wigner in 1929 and offer new possibilities for integrated optical elements and analogous realizations with cold atoms and optical trapping of particles.
Astrophysical bound on the Majoron-Higgs boson coupling
International Nuclear Information System (INIS)
Bertolini, S.; Santamaria, A.
1988-01-01
We show that the coupling of the ''standard'' Higgs boson to Majorons, that could lead to a very fast decay of the neutral Higgs scalar to invisible modes, can be bounded using astrophysical arguments. We discuss the relevance of this bound for low-energy phenomenology related to majoron production. The bound so obtained may also jeopardize the stability of the VEV hierarchy in the doublet and triplet majoron models if the mass of the top quark is less than the W mass. The analysis applies generally to models which exhibit (pseudo-) Golstone bosons in the spectrum. 15 refs., 1 fig
Bounds on the Error Probability of Raptor Codes
Lázaro, Francisco; Liva, Gianluigi; Paolini, Enrico; Bauch, Gerhard
2016-01-01
In this paper q-ary Raptor codes under ML decoding are considered. An upper bound on the probability of decoding failure is derived using the weight enumerator of the outer code, or its expected weight enumerator if the outer code is drawn randomly from some ensemble of codes. The bound is shown to be tight by means of simulations. This bound provides a new insight into Raptor codes since it shows how Raptor codes can be analyzed similarly to a classical fixed-rate serial concatenation.
Thermodynamic Upper Bound on Broadband Light Coupling with Photonic Structures
Yu, Zongfu
2012-10-01
The coupling between free space radiation and optical media critically influences the performance of optical devices. We show that, for any given photonic structure, the sum of the external coupling rates for all its optical modes are subject to an upper bound dictated by the second law of thermodynamics. Such bound limits how efficient light can be coupled to any photonic structure. As one example of application, we use this upper bound to derive the limit of light absorption in broadband solar absorbers. © 2012 American Physical Society.
Confidence bounds on an empirical cumulative distribution function
International Nuclear Information System (INIS)
Andres, T.H.
1986-11-01
Methods are developed for using data from an empirical cumulative distribution function (CDF) to generate, at each point in the range of the data an upper confidence bound on the estimated value of the underlying CDF. Applications are demonstrated where a confidence bound is applied to the empirical distribution of maximum effective annual dose equivalent obtained from a set of Monte Carlo simulations in an environmental assessment of nuclear fuel waste disposal. This bound can then be used to compare the empirical dose CDF with possible regulatory guidelines for dose from a disposal facility. Methods presented in the report can be used to select the number of simulations needed to meet such guidelines
OPRA capacity bounds for selection diversity over generalized fading channels
Hanif, Muhammad Fainan
2014-05-01
Channel side information at the transmitter can increase the average capacity by enabling optimal power and rate adaptation. The resulting optimal power and rate adaptation (OPRA) capacity rarely has a closed-form analytic expression. In this paper, lower and upper bounds on OPRA capacity for selection diversity scheme are presented. These bounds hold for variety of fading channels including log-normal and generalized Gamma distributed models and have very simple analytic expressions for easy evaluation even for kth best path selection. Some selected numerical results show that the newly proposed bounds closely approximate the actual OPRA capacity. © 2014 IEEE.
Lateral translation of covalently bound fullerenes
International Nuclear Information System (INIS)
Humphry, M J; Beton, P H; Keeling, D L; Fawcett, R H J; Moriarty, P; Butcher, M J; Birkett, P R; Walton, D R M; Taylor, R; Kroto, H W
2006-01-01
Lateral manipulation of fullerenes on clean silicon surfaces may be induced by either an attractive or repulsive interaction between adsorbed molecules and the tip of a scanning probe microscope, and can result in a complex response arising from molecular rolling. The model for rolling is supported by new results which show that manipulation is suppressed for adsorbed functionalized fullerenes due to the presence of phenyl sidegroups. The influence of varying the dwell time of the tip during manipulation is also reported. By reducing this time to a value which is less than the response time of the feedback control loop it is possible to induce manipulation in a quasi-constant height mode which is accompanied by large increases/decreases in current
P2-16: Dual-Bound Model and the Role of Time Bound in Perceptual Decision Making
Directory of Open Access Journals (Sweden)
Daeseob Lim
2012-10-01
Full Text Available The diffusion model (DM encapsulates the dynamics of perceptual decision within a ‘diffusion field’ that is defined by a basis with sensory-evidence (SE and time vectors. At the core of the DM, it assumes that a decision is not made until an evidence particle drifts in the diffusion field and eventually hits one of the two pre-fixed bounds defined in the SE axis. This assumption dictates when and which choice is made by referring to when and which bound will be hit by the evidence particle. What if urgency pressures the decision system to make a choice even when the evidence particle has yet hit the SE bound? Previous modeling attempts at coping with time pressure, despite differences in detail, all manipulated the coordinate of SE bounds. Here, we offer a novel solution by adopting another bound on the time axis. This ‘dual-bound’ model (DBM posits that decisions can also be made when the evidence particle hits a time bound, which is determined on a trial-by-trial basis by a ‘perceived time interval’ – how long the system can stay in the ‘diffusion’ field. The classic single-bound model (SBM exhibited systematic errors in predicting both the reaction time distributions and the time-varying bias in choice. Those errors were not corrected by previously proposed variants of the SBM until the time bound was introduced. The validity of the DBM was further supported by the strong across-individual correlation between observed precision of interval timing and the predicted trial-by-trial variability of the time bound.
Optimum Cooperative UAV Sensing Based on Cramer-Rao Bound
National Research Council Canada - National Science Library
Gu, G; Chandler, P. R; Schumacher, C. J; Sparks, A; Pachter, M
2005-01-01
.... Based on the Cramer-Rao bound, we are able to derive the minimum achievable error variance in estimation of the position and the velocity of the GMT, and obtain the optimal geometries of the UAV...
Sampling and identification of gaseous and particle bounded air pollutants
International Nuclear Information System (INIS)
Kettrup, A.
1993-01-01
Air pollutants are gaseous, components of aerosols or particle bounded. Sampling, sample preparation, identification and quantification of compounds depend from kind and chemical composition of the air pollutants. Quality assurance of analytical data must be guaranted. (orig.) [de
Inequalities Involving Upper Bounds for Certain Matrix Operators
Indian Academy of Sciences (India)
Home; Journals; Proceedings – Mathematical Sciences; Volume 116; Issue 3. Inequalities Involving Upper Bounds for Certain Matrix Operators. R Lashkaripour D Foroutannia. Volume ... Keywords. Inequality; norm; summability matrix; Hausdorff matrix; Hilbert matrix; weighted sequence space; Lorentz sequence space.
Ensemble of classifiers based network intrusion detection system performance bound
CSIR Research Space (South Africa)
Mkuzangwe, Nenekazi NP
2017-11-01
Full Text Available This paper provides a performance bound of a network intrusion detection system (NIDS) that uses an ensemble of classifiers. Currently researchers rely on implementing the ensemble of classifiers based NIDS before they can determine the performance...
Possible circumvention of Parker's bound on galactic magnetic monopoles
International Nuclear Information System (INIS)
Dicus, D.A.; Teplitz, V.L.
1983-04-01
There is a possibility that a magnetic monople has observed. The monopole density implied by the observation appears to violate bounds on the density of such particles derived from the total mass density of the universe and from the existence of galactic magnetic fields. We show that the observation is not inconsistent with these bounds if the monopoles and antimonopoles are bound into positronium - like states with principal quantum n high enough so that the earth's magnetic field will break them apart, but small enough so that the weaker galactic mangetic field will not. We determine a range of values for n and show that lifetimes for such bound states are longer than the current age of the universe
Circumvention of Parker's bound on galactic magnetic monopoles
International Nuclear Information System (INIS)
Dicus, D.A.; Teplitz, V.L.; Maryland Univ., College Park
1983-01-01
There is a possibility that a magnetic monopole has been observed. The monopole density implied by the observation appears to violate bounds on the density of such particles derived from the total mass density of the Universe and from the existence of galactic magnetic fields. It is shown that the observation is not inconsistent with these bounds if the monopoles and antimonopoles are bound into positronium like states with principal quantum n high enough so that the Earth's magnetic field will break them apart, but small enough so that the weaker galactic magnetic field will not. A range of values for n are determined and show that lifetimes for such bound states are longer than the current age of the Universe. (author)
Application of Beyond Bound Decoding for High Speed Optical Communications
DEFF Research Database (Denmark)
Li, Bomin; Larsen, Knud J.; Vegas Olmos, Juan José
2013-01-01
This paper studies the application of beyond bound decoding method for high speed optical communications. This hard-decision decoding method outperforms traditional minimum distance decoding method, with a total net coding gain of 10.36 dB....
An upper bound on Q-star masses
International Nuclear Information System (INIS)
Hochron, D.R.; Selipsky, S.B.
1992-06-01
Q-stars (the gravitational generalization of Q-balls, strongly bound bulk matter that an appear in field theories of strongly interacting hadrons) are the only known impact objects consistent with the known bulk structure of nuclei and chiral symmetry that evade the Rhoades-Ruffini upper bound of 3.2M circle-dot . Generic bounds are quite weak: M Q-star circle-dot . If, however, we assume that the 1.558 ms pulsar is a Q-star, equilibrium. A stability criteria of rotating fluids place a much stronger upper bound of M c ≤ 5.3M circle-dot on such models under certain special assumptions. This has important implications for heavy compact objects such as Cygnus X-1
Capacity bounds for parallel IM-DD optical wireless channels
Chaaban, Anas
2016-07-26
A system consisting of parallel intensity-modulation direct-detection optical wireless channels with a total average intensity constraint is studied. Capacity upper and lower bounds for this system are derived. If channel-state information is available at the transmitter, the bounds have to be optimized with respect to intensity allocation over the parallel channels. The optimization of the lower bound is non-convex, however, the Karush-Kuhn-Tucker conditions can be used to find a list of possible solutions one of which is optimal. The optimal solution can then be found by an exhaustive search algorithm, which is computationally expensive. To overcome this, we propose a low-complexity intensity allocation algorithm which is nearly optimal. The optimized capacity lower bound coincides with the capacity at high signal-to-noise ratio. © 2016 IEEE.
Comparing two reliability upper bounds for multistate systems
International Nuclear Information System (INIS)
Meng, Fan C.
2005-01-01
The path-cut reliability bound due to Esary and Proschan [J. Am. Stat. Assoc. 65 (1970) 329] and the minimax reliability bound due to Barlow and Proschan [Statistical Theory of Reliability and Life Testing: Probability Models, 1981] for binary systems have been generalized to multistate systems by Block and Savits [J. Appl. Probab. 19 (1982) 391]. Some comparison results concerning the two multistate lower bounds for various types of multistate systems are given by Meng [Probab. Eng. Inform. Sci. 16 (2002) 485]. In this note we compare the two multistate upper bounds and present results which generalize some previous ones obtained by Maymin [J. Stat. Plan. Inference 16 (1987) 337] for binary systems. Examples are given to illustrate our results
Deeply-bound protons in 208 Pb
van Batenburg, M. F.
2001-03-01
another Icelandic glacier (S¢lheimajökull) was also influenced by precipitation variations. Equilibrium Line Elevation at the end of the melting season (ELAe) is a proxy for Bm, but the Equilibrium Line (EL) is mostly not visible on AVHRR images when it is located above its position of the previous year(s). EL detection is further hindered by clouds and a gradual transition between ice and firn or snow. Consequently, detection of the ELAe on albedo images is not particularly useful for estimating Bm. Instead, we propose to study the mean albedo of the entire ice cap throughout the melting season, so that all available information about the surface albedo is taken into account. The mean net potential global radiation, which can be estimated from the mean surface albedo alone, is found to relate linearly to Bm. Like AVHRR images, Synthetic Aperture Radar (SAR) images only display the surface firn line as a distinct boundary and not the snow line (i.e. melting snow and firn have the same backscatter and albedo signatures). On the other hand, winter SAR images of Vatnajökull display sub-surface firn-ice transitions, but these do not correspond to the late summer surface firn line. Unlike albedo images, SAR images do not display inter-annual variations of the signal within the accumulation area that are clearly related to Bm and are therefore less usefull for mass balance retrieval. For the north-western part of Vatnajökull the indirect observations (satellite and modelled) correspond with the direct (in situ) observations. Only for one year the different estimates strongly diverge, probably due to a lack of satellite images and an erroneously modeled distribution of precipitation. We compute the best estimate of the mass balance of north-western Vatnajökull as the weighted mean of the individual estimates. For the part of Vatnajökull where the mass balance has not been measured, we can use the indirect methods to estimate relative variations in Bm.
Functions with bounded variation in locally convex space
Duchoň, Miloslav; Debiève, Camille
2011-01-01
The present paper is concerned with some properties of functions with values in locally convex vector space, namely functions having bounded variation and generalizations of some theorems for functions with values in locally convex vector spaces replacing Banach spaces, namely Theorem: If X is a sequentially complete locally convex vector space, then the function x(·): [a, b] → X having a bounded variation on the interval [a, b] defines a vector-valued measure m on borelian subsets of [a, b] ...
Buneman instability and Pierce instability in a collisionless bounded plasma
International Nuclear Information System (INIS)
Iizuka, Satoru; Saeki, Koichi; Sato, Noriyoshi; Hatta, Yoshisuke
1983-01-01
A systematic experiment is performed on the Buneman instability and the Pierce instability in a bounded plasma consisting of beam electrons and stationary ions. Current fluctuations are confirmed to be induced by the Buneman instability. On the other hand, the Pierce instability gives rise to a current limitation. The phenomena are well explained by Mikhailovskii's theory taking account of ion motion in a bounded plasma. (author)
Computing variational bounds for flow through random aggregates of Spheres
International Nuclear Information System (INIS)
Berryman, J.G.
1983-01-01
Known formulas for variational bounds on Darcy's constant for slow flow through porous media depend on two-point and three-poiint spatial correlation functions. Certain bounds due to Prager and Doi depending only a two-point correlation functions have been calculated for the first time for random aggregates of spheres with packing fractions (eta) up to eta = 0.64. Three radial distribution functions for hard spheres were tested for eta up to 0.49: (1) the uniform distribution or ''well-stirred approximation,'' (2) the Percus Yevick approximation, and (3) the semi-empirical distribution of Verlet and Weis. The empirical radial distribution functions of Benett andd Finney were used for packing fractions near the random-close-packing limit (eta/sub RCP/dapprox.0.64). An accurate multidimensional Monte Carlo integration method (VEGAS) developed by Lepage was used to compute the required two-point correlation functions. The results show that Doi's bounds are preferred for eta>0.10 while Prager's bounds are preferred for eta>0.10. The ''upper bounds'' computed using the well-stirred approximation actually become negative (which is physically impossible) as eta increases, indicating the very limited value of this approximation. The other two choices of radial distribution function give reasonable results for eta up to 0.49. However, these bounds do not decrease with eta as fast as expected for large eta. It is concluded that variational bounds dependent on three-point correlation functions are required to obtain more accurate bounds on Darcy's constant for large eta
Offsite Radiological Consequence Analysis for the Bounding Flammable Gas Accident
Carro, C A
2003-01-01
This document quantifies the offsite radiological consequences of the bounding flammable gas accident for comparison with the 25 rem Evaluation Guideline established in DOE-STD-3009, Appendix A. The bounding flammable gas accident is a detonation in a single-shell tank The calculation applies reasonably conservation input parameters in accordance with DOE-STD-3009, Appendix A, guidance. Revision 1 incorporates comments received from Office of River Protection.
Decreasing Absolute Risk Aversion and Option Pricing Bounds
Antonella Basso; Paolo Pianca
1997-01-01
In this paper efficient bounds for the price of a call option are obtained using the decreasing absolute risk aversion (DARA) dominance rule. Such lower and upper bounds are obtained minimizing and maximizing, respectively, the objective function of a nonlinear optimization problem. An explicit formula (related to an exponential utility function) is given for the special case of three states of nature. A large number of experiments have been carried out and the numerical results support the c...
Temperature bounds in a model of laminar flames
International Nuclear Information System (INIS)
Kirane, M.; Badraoui, S.
1994-06-01
We consider reaction-diffusion equations coupling temperature and mass fraction in one-step-reaction model of combustion in R N . Uniform temperature bounds are derived when the Lewis number is less than one. This result completes the case of Lewis number greater than one studied by J.D. Avrin and M. Kirane ''Temperature growth and temperature bounds in special cases of combustion models'' (to appear in Applicable Analysis). (author). 5 refs
Probabilistic Lower Bounds for Approximation by Shallow Perceptron Networks
Czech Academy of Sciences Publication Activity Database
Kůrková, Věra; Sanguineti, M.
2017-01-01
Roč. 91, July (2017), s. 34-41 ISSN 0893-6080 R&D Projects: GA ČR GA15-18108S Institutional support: RVO:67985807 Keywords : shallow networks * perceptrons * model complexity * lower bounds on approximation rates * Chernoff-Hoeffding bounds Subject RIV: IN - Informatics, Computer Science OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 5.287, year: 2016
Infinite Horizon Discrete Time Control Problems for Bounded Processes
Directory of Open Access Journals (Sweden)
2009-03-01
Full Text Available We establish Pontryagin Maximum Principles in the strong form for infinite horizon optimal control problems for bounded processes, for systems governed by difference equations. Results due to Ioffe and Tihomirov are among the tools used to prove our theorems. We write necessary conditions with weakened hypotheses of concavity and without invertibility, and we provide new results on the adjoint variable. We show links between bounded problems and nonbounded ones. We also give sufficient conditions of optimality.
A lower bound on the mass of dark matter particles
International Nuclear Information System (INIS)
Boyarsky, Alexey; Ruchayskiy, Oleg; Iakubovskyi, Dmytro
2009-01-01
We discuss the bounds on the mass of Dark Matter (DM) particles, coming from the analysis of DM phase-space distribution in dwarf spheroidal galaxies (dSphs). After reviewing the existing approaches, we choose two methods to derive such a bound. The first one depends on the information about the current phase space distribution of DM particles only, while the second one uses both the initial and final distributions. We discuss the recent data on dSphs as well as astronomical uncertainties in relevant parameters. As an application, we present lower bounds on the mass of DM particles, coming from various dSphs, using both methods. The model-independent bound holds for any type of fermionic DM. Stronger, model-dependent bounds are quoted for several DM models (thermal relics, non-resonantly and resonantly produced sterile neutrinos, etc.). The latter bounds rely on the assumption that baryonic feedback cannot significantly increase the maximum of a distribution function of DM particles. For the scenario in which all the DM is made of sterile neutrinos produced via non-resonant mixing with the active neutrinos (NRP) this gives m NRP > 1.7 keV. Combining these results in their most conservative form with the X-ray bounds of DM decay lines, we conclude that the NRP scenario remains allowed in a very narrow parameter window only. This conclusion is independent of the results of the Lyman-α analysis. The DM model in which sterile neutrinos are resonantly produced in the presence of lepton asymmetry remains viable. Within the minimal neutrino extension of the Standard Model (the νMSM), both mass and the mixing angle of the DM sterile neutrino are bounded from above and below, which suggests the possibility for its experimental search
PENERAPAN BRANCH AND BOUND ALGORITHM DALAM OPTIMALISASI PRODUKSI ROTI
GEDE SURYAWAN; NI KETUT TARI TASTRAWATI; KARTIKA SARI
2016-01-01
Companies which engaged in production activities such as Ramadhan Bakery would want optimal profit in their every production. The aim of this study was to find optimal profit and optimal combination of bread production (original chocolate bread, extra chocolate bread, rounding chocolate bread and mattress chocolate bread) that was produced by Ramadhan Bakery by applying Branch and Bound Algorithm method. Branch and Bound Algorithm is one method to solve Integer Programming’s problems other th...
Exact Solutions of Relativistic Bound State Problem for Spinless Bosons
Aslanzadeh, M.; Rajabi, A. A.
2017-01-01
We investigated in detail the relativistic bound states of spin-zero bosons under the influence of Coulomb-plus-linear potentials with an arbitrary combination of scalar and vector couplings. Through an exact analytical solution of three-dimensional Klein-Gordon equation, closed form expressions were derived for energy eigenvalues and wave functions and some correlations between potential parameters were found. We also presented the relativistic description of bound states and nonrelativistic limit of the problem in some special cases.
An upper bound for the proton temperature anisotrophy
International Nuclear Information System (INIS)
Gary, S.P.
1994-01-01
This tutorial describes recent research concerning the upper bound on the hot proton temperature anisotropy imposed by wave-particle scattering due to enhanced fluctuations from the electromagnetic proton cyclotron anisotropy instability. This upper bound, which has been observed in both the magnetosheath and the outer magnetosphere, represents a limited closure relation for the equations of anisotropic magnetohydrodynamics. Such a closure relation has the potential to improve the predictive capability of large-scale anisotropic models of the magnetosphere
Capacity Bounds and Mapping Design for Binary Symmetric Relay Channels
Majid Nasiri Khormuji; Mikael Skoglund
2012-01-01
Capacity bounds for a three-node binary symmetric relay channel with orthogonal components at the destination are studied. The cut-set upper bound and the rates achievable using decode-and-forward (DF), partial DF and compress-and-forward (CF) relaying are first evaluated. Then relaying strategies with finite memory-length are considered. An efficient algorithm for optimizing the relay functions is presented. The Boolean Fourier transform is then employed to unveil the structure of the optimi...
21 CFR 862.1640 - Protein-bound iodine test system.
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Protein-bound iodine test system. 862.1640 Section... Systems § 862.1640 Protein-bound iodine test system. (a) Identification. A protein-bound iodine test system is a device intended to measure protein-bound iodine in serum. Measurements of protein-bound...
Chloroplast protein synthesis: thylakoid bound polysomes synthesize thylakoid proteins
Energy Technology Data Exchange (ETDEWEB)
Hurewitz, J.; Jagendorf, A.T.
1986-04-01
Previous work indicated more polysomes bound to pea thylakoids in light than in the dark, in vivo. With isolated intact chloroplasts incubated in darkness, 24 to 74% more RNA was thylakoid-bound at pH 8.3 than at pH 7. Thus the major effect of light in vivo may be due to higher stroma pH. In isolated pea chloroplasts, initiation inhibitors (pactamycin and kanamycin) decreased the extent of RNA binding, and elongation inhibitors (lincomycin and streptomycin) increased it. Thus translation initiation and termination probably control the cycling of bound ribosomes. While only 3 to 6% of total RNA is in bound polysomes the incorporation of /sup 3/H-Leu into thylakoids was proportional to the amount of this bound RNA. When Micrococcal nuclease-treated thylakoids were added to labeled runoff translation products of stroma ribosomes, less than 1% of the label adhered to the added membranes; but 37% of the labeled products made by thylakoid polysomes were bound. These data support the concept that stroma ribosomes are recruited into thylakoid proteins.
Dynamic Garment Simulation based on Hybrid Bounding Volume Hierarchy
Directory of Open Access Journals (Sweden)
Zhu Dongyong
2016-12-01
Full Text Available In order to solve the computing speed and efficiency problem of existing dynamic clothing simulation, this paper presents a dynamic garment simulation based on a hybrid bounding volume hierarchy. It firstly uses MCASG graph theory to do the primary segmentation for a given three-dimensional human body model. And then it applies K-means cluster to do the secondary segmentation to collect the human body’s upper arms, lower arms, upper legs, lower legs, trunk, hip and woman’s chest as the elementary units of dynamic clothing simulation. According to different shapes of these elementary units, it chooses the closest and most efficient hybrid bounding box to specify these units, such as cylinder bounding box and elliptic cylinder bounding box. During the process of constructing these bounding boxes, it uses the least squares method and slices of the human body to get the related parameters. This approach makes it possible to use the least amount of bounding boxes to create close collision detection regions for the appearance of the human body. A spring-mass model based on a triangular mesh of the clothing model is finally constructed for dynamic simulation. The simulation result shows the feasibility and superiority of the method described.
Opinion formation with time-varying bounded confidence.
Zhang, YunHong; Liu, QiPeng; Zhang, SiYing
2017-01-01
When individuals in social groups communicate with one another and are under the influence of neighbors' opinions, they typically revise their own opinions to adapt to such peer opinions. The individual threshold of bounded confidence will thus be affected by both a change in individual confidence and by neighbor influence. Individuals thus update their own opinions with new bounded confidence, while their updated opinions also influence their neighbors' opinions. Based on this reasoned factual assumption, we propose an opinion dynamics model with time-varying bounded confidence. A directed network is formed by the rule of the individual bounded confidence threshold. The threshold of individual bounded confidence involves both confidence variation and the in/out degree of the individual node. When the confidence variation is greater, an individual's confidence in persisting in his own opinion in interactions is weaker, and the individual is more likely to adopt neighbors' opinions. In networks, the in/out degree is determined by individual neighbors. Our main research involves the process of opinion evolution and the basic laws of opinion cluster formation. Group opinions converge exponentially to consensus with stable neighbors. An individual opinion evolution is determined by the average neighbor opinion effect strength. We also explore the conditions involved in forming a stable neighbor relationship and the influence of the confidence variation in the convergence of the threshold of bounded confidence. The results show that the influence on opinion evolution is greater with increased confidence variation.
Studies on bound (14)C-chlorsulfuron residues in soil.
Guo, Jiangfeng; Sun, Jinhe
2002-04-10
The cause for phytotoxicity of bound residues of chlorsulfuron (2-chloro-N-[[4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino] carbonyl]benzenesulfonamide) to rotational crops is unknown. This study was conducted to determine the formation of nonextractable (bound) residues of chlorsulfuron in soil, and the distribution of bound residues in different organic matter fractions. The results showed that over 150 days, the extractable fraction of (14)C-residues decreased to 25.1% of applied chlorsulfuron, while bound residues concurrently increased to 47.1%. The distribution of (14)C-bound residues in soil organic matter fractions followed an order of humic acid (HA) humin humin fraction increased with time. After soil treatment by autoclaving, it was found that bound (14)C-chlorsulfuron residues became available again in the soil. One of the released products was 2-amino-4-hydroxyl-6-methyl-1,3,5-triazine (identified by GC-MS), which is a degradation product of chlorsulfuron.
On the Content Bound for Real Quadratic Field Extensions
Directory of Open Access Journals (Sweden)
Robert G. Underwood
2012-12-01
Full Text Available Let K be a finite extension of Q and let S = {ν} denote the collection of K normalized absolute values on K. Let V+K denote the additive group of adeles over K and let K ≥0 c : V + → R denote the content map defined as c({aν } = Q K ν ∈S ν (aν for {aν } ∈ V+K A classical result of J. W. S. Cassels states that there is a constant c > 0 depending only on the field K with the following property: if {aν } ∈ V+K with c({aν } > c, then there exists a non-zero element b ∈ K for which ν (b ≤ ν (aν , ∀ν ∈ S. Let cK be the greatest lower bound of the set of all c that satisfy this property. In the case that K is a real quadratic extension there is a known upper bound for cK due to S. Lang. The purpose of this paper is to construct a new upper bound for cK in the case that K has class number one. We compare our new bound with Lang’s bound for various real quadratic extensions and find that our new bound is better than Lang’s in many instances.
Natural bounds on herbivorous coral reef fishes
Hoey, Andrew S.; Williams, Gareth J.; Williams, Ivor D.
2016-01-01
Humans are an increasingly dominant driver of Earth's biological communities, but differentiating human impacts from natural drivers of ecosystem state is crucial. Herbivorous fish play a key role in maintaining coral dominance on coral reefs, and are widely affected by human activities, principally fishing. We assess the relative importance of human and biophysical (habitat and oceanographic) drivers on the biomass of five herbivorous functional groups among 33 islands in the central and western Pacific Ocean. Human impacts were clear for some, but not all, herbivore groups. Biomass of browsers, large excavators, and of all herbivores combined declined rapidly with increasing human population density, whereas grazers, scrapers, and detritivores displayed no relationship. Sea-surface temperature had significant but opposing effects on the biomass of detritivores (positive) and browsers (negative). Similarly, the biomass of scrapers, grazers, and detritivores correlated with habitat structural complexity; however, relationships were group specific. Finally, the biomass of browsers and large excavators was related to island geomorphology, both peaking on low-lying islands and atolls. The substantial variability in herbivore populations explained by natural biophysical drivers highlights the need for locally appropriate management targets on coral reefs. PMID:27881745
Edge maps: Representing flow with bounded error
Bhatia, Harsh
2011-03-01
Robust analysis of vector fields has been established as an important tool for deriving insights from the complex systems these fields model. Many analysis techniques rely on computing streamlines, a task often hampered by numerical instabilities. Approaches that ignore the resulting errors can lead to inconsistencies that may produce unreliable visualizations and ultimately prevent in-depth analysis. We propose a new representation for vector fields on surfaces that replaces numerical integration through triangles with linear maps defined on its boundary. This representation, called edge maps, is equivalent to computing all possible streamlines at a user defined error threshold. In spite of this error, all the streamlines computed using edge maps will be pairwise disjoint. Furthermore, our representation stores the error explicitly, and thus can be used to produce more informative visualizations. Given a piecewise-linear interpolated vector field, a recent result [15] shows that there are only 23 possible map classes for a triangle, permitting a concise description of flow behaviors. This work describes the details of computing edge maps, provides techniques to quantify and refine edge map error, and gives qualitative and visual comparisons to more traditional techniques. © 2011 IEEE.
Directory of Open Access Journals (Sweden)
G. N. Mathioudakis
2016-09-01
Full Text Available In this work, biocidal polymers with antimicrobial quaternized ammonium groups introduced in the polymer biocidal chains either through covalent attachment or electrostatic interaction have been separately incorporated in a poly (methyl methacrylate polymer matrix. The objective of present study was to highlight the release characteristics of biocidal polymers, primarily in saline but also in water ethanol solutions, utilizing UV-Vis absorption and Surface Enhanced Raman Scattering (SERS. It is shown that through the combination of UV-Vis and SERS techniques, upon the release process, it is possible the discrimination of the polymeric backbone and the electrostatically bound biocidal species. Moreover, it is found that electrostatically bound and covalently attached biocidal species show different SERS patterns. The long term aim is the development of antimicrobial polymeric materials containing both ionically bound and covalently attached quaternary ammonium thus achieving a dual functionality in a single component polymeric design.
Embedding and Knotting of Flat Surfaces
DEFF Research Database (Denmark)
Røgen, Peter
1999-01-01
In 3-space, any compact surface with nonempty boundary is isotopic to a flat (zero Gaussian curvature) surface and two such flat surfaces are isotopic through flat surfaces if and only if they are isotopic through ordinary surfaces. Hereby the isotopy classes of flat surfaces are in one-to-one co......In 3-space, any compact surface with nonempty boundary is isotopic to a flat (zero Gaussian curvature) surface and two such flat surfaces are isotopic through flat surfaces if and only if they are isotopic through ordinary surfaces. Hereby the isotopy classes of flat surfaces are in one......-to-one correspondence with the isotopy classes of ordinary surfaces which have no constraint on their curvature. Applied to Seifert surfaces we get: Any simple closed space curve can be deformed until it bounds a flat orientable surface....
Isotopic meshing of implicit surfaces
Plantinga, Simon; Vegter, Gert
Implicit surfaces are given as the zero set of a function F : R3→R. Although several algorithms exist for generating piecewise linear approximations, most of these are based on a user-defined stepsize or bounds to indicate the precision, and therefore cannot guarantee topological correctness.
International Nuclear Information System (INIS)
Wylie, Benjamin J.; Dzikovski, Boris G.; Pawsey, Shane; Caporini, Marc; Rosay, Melanie; Freed, Jack H.; McDermott, Ann E.
2015-01-01
We demonstrate that dynamic nuclear polarization of membrane proteins in lipid bilayers may be achieved using a novel polarizing agent: pairs of spin labels covalently bound to a protein of interest interacting at an intermolecular interaction surface. For gramicidin A, nitroxide tags attached to the N-terminal intermolecular interface region become proximal only when bimolecular channels forms in the membrane. We obtained signal enhancements of sixfold for the dimeric protein. The enhancement effect was comparable to that of a doubly tagged sample of gramicidin C, with intramolecular spin pairs. This approach could be a powerful and selective means for signal enhancement in membrane proteins, and for recognizing intermolecular interfaces
Resistance of soil-bound prions to rumen digestion.
Directory of Open Access Journals (Sweden)
Samuel E Saunders
Full Text Available Before prion uptake and infection can occur in the lower gastrointestinal system, ingested prions are subjected to anaerobic digestion in the rumen of cervids and bovids. The susceptibility of soil-bound prions to rumen digestion has not been evaluated previously. In this study, prions from infectious brain homogenates as well as prions bound to a range of soils and soil minerals were subjected to in vitro rumen digestion, and changes in PrP levels were measured via western blot. Binding to clay appeared to protect noninfectious hamster PrP(c from complete digestion, while both unbound and soil-bound infectious PrP(Sc proved highly resistant to rumen digestion. In addition, no change in intracerebral incubation period was observed following active rumen digestion of unbound hamster HY TME prions and HY TME prions bound to a silty clay loam soil. These results demonstrate that both unbound and soil-bound prions readily survive rumen digestion without a reduction in infectivity, further supporting the potential for soil-mediated transmission of chronic wasting disease (CWD and scrapie in the environment.
Bionic Control of Cheetah Bounding with a Segmented Spine.
Wang, Chunlei; Wang, Shigang
2016-01-01
A cheetah model is built to mimic real cheetah and its mechanical and dimensional parameters are derived from the real cheetah. In particular, two joints in spine and four joints in a leg are used to realize the motion of segmented spine and segmented legs which are the key properties of the cheetah bounding. For actuating and stabilizing the bounding gait of cheetah, we present a bioinspired controller based on the state-machine. The controller mainly mimics the function of the cerebellum to plan the locomotion and keep the body balance. The haptic sensor and proprioception system are used to detect the trigger of the phase transition. Besides, the vestibular modulation could perceive the pitching angle of the trunk. At last, the cerebellum acts as the CPU to operate the information from the biological sensors. In addition, the calculated results are transmitted to the low-level controller to actuate and stabilize the cheetah bounding. Moreover, the delay feedback control method is employed to plan the motion of the leg joints to stabilize the pitching motion of trunk with the stability criterion. Finally, the cyclic cheetah bounding with biological properties is realized. Meanwhile, the stability and dynamic properties of the cheetah bounding gait are analyzed elaborately.
Class-specific Error Bounds for Ensemble Classifiers
Energy Technology Data Exchange (ETDEWEB)
Prenger, R; Lemmond, T; Varshney, K; Chen, B; Hanley, W
2009-10-06
The generalization error, or probability of misclassification, of ensemble classifiers has been shown to be bounded above by a function of the mean correlation between the constituent (i.e., base) classifiers and their average strength. This bound suggests that increasing the strength and/or decreasing the correlation of an ensemble's base classifiers may yield improved performance under the assumption of equal error costs. However, this and other existing bounds do not directly address application spaces in which error costs are inherently unequal. For applications involving binary classification, Receiver Operating Characteristic (ROC) curves, performance curves that explicitly trade off false alarms and missed detections, are often utilized to support decision making. To address performance optimization in this context, we have developed a lower bound for the entire ROC curve that can be expressed in terms of the class-specific strength and correlation of the base classifiers. We present empirical analyses demonstrating the efficacy of these bounds in predicting relative classifier performance. In addition, we specify performance regions of the ROC curve that are naturally delineated by the class-specific strengths of the base classifiers and show that each of these regions can be associated with a unique set of guidelines for performance optimization of binary classifiers within unequal error cost regimes.
Bionic Control of Cheetah Bounding with a Segmented Spine
Directory of Open Access Journals (Sweden)
Chunlei Wang
2016-01-01
Full Text Available A cheetah model is built to mimic real cheetah and its mechanical and dimensional parameters are derived from the real cheetah. In particular, two joints in spine and four joints in a leg are used to realize the motion of segmented spine and segmented legs which are the key properties of the cheetah bounding. For actuating and stabilizing the bounding gait of cheetah, we present a bioinspired controller based on the state-machine. The controller mainly mimics the function of the cerebellum to plan the locomotion and keep the body balance. The haptic sensor and proprioception system are used to detect the trigger of the phase transition. Besides, the vestibular modulation could perceive the pitching angle of the trunk. At last, the cerebellum acts as the CPU to operate the information from the biological sensors. In addition, the calculated results are transmitted to the low-level controller to actuate and stabilize the cheetah bounding. Moreover, the delay feedback control method is employed to plan the motion of the leg joints to stabilize the pitching motion of trunk with the stability criterion. Finally, the cyclic cheetah bounding with biological properties is realized. Meanwhile, the stability and dynamic properties of the cheetah bounding gait are analyzed elaborately.
Research on culture-bound syndromes: new directions.
Guarnaccia, P J; Rogler, L H
1999-09-01
The unprecedented inclusion of culture-bound syndromes in DSM-IV provides the opportunity for highlighting the need to study such syndromes and the occasion for developing a research agenda to study them. The growing ethnic and cultural diversity of the U.S. population presents a challenge to the mental health field to develop truly cross-cultural approaches to mental health research and services. In this article, the authors provide a critique of previous analyses of the relationship between culture-bound syndromes and psychiatric diagnoses. They highlight the problems in previous classificatory exercises, which tend to focus on subsuming the culture-bound syndromes into psychiatric categories and fail to fully investigate these syndromes on their own terms. A detailed research program based on four key questions is presented both to understand culture-bound syndromes within their cultural context and to analyze the relationship between these syndromes and psychiatric disorders. Results of over a decade of research on ataques de nervios, a Latino-Caribbean cultural syndrome, are used to illustrate this research program. The four questions focus on the nature of the phenomenon, the social-cultural location of sufferers, the relationship of culture-bound syndromes to psychiatric disorders, and the social and psychiatric history of the syndrome in the life course of the sufferer.
Information-Theoretic Bounded Rationality and ε-Optimality
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Daniel A. Braun
2014-08-01
Full Text Available Bounded rationality concerns the study of decision makers with limited information processing resources. Previously, the free energy difference functional has been suggested to model bounded rational decision making, as it provides a natural trade-off between an energy or utility function that is to be optimized and information processing costs that are measured by entropic search costs. The main question of this article is how the information-theoretic free energy model relates to simple ε-optimality models of bounded rational decision making, where the decision maker is satisfied with any action in an ε-neighborhood of the optimal utility. We find that the stochastic policies that optimize the free energy trade-off comply with the notion of ε-optimality. Moreover, this optimality criterion even holds when the environment is adversarial. We conclude that the study of bounded rationality based on ε-optimality criteria that abstract away from the particulars of the information processing constraints is compatible with the information-theoretic free energy model of bounded rationality.
Optimal bounds on dissipation in stress driven flow
Tang, W.; Caulfield, C. P.; Young, W. R.
2003-11-01
We calculate the optimal upper and lower bounds, subject to the assumption of streamwise invariance, on the long-time-averaged mechanical energy dissipation rate ɛ within the flow of an incompressible viscous fluid of constant kinematic viscosity ν and depth h that is driven by a constant stress τ, defining an appropriate Grashof number G=τ h^2/ν^2. We show that ɛ ≤ τ^2/ν, i.e. the dissipation is bounded above by the dissipation associated with the laminar solution u=τ z hat ^x/ν. By using the the variational background method, (due to Constantin, Doering, and Hopf) and numerical continuation, we also generate the best possible rigorous lower bounds on the dissipation for arbitrary Grashof numbers. As G arrow ∞, we show that the dissipation is bounded below by ɛm = O(τ^3/2/h), with a numerical coefficient that we identify explicitly. The associated bounding solution has thin boundary layers at the top and bottom of the fluid layer with a deep intermediate region of weak shear.
Resistance of Soil-Bound Prions to Rumen Digestion
Saunders, Samuel E.; Bartelt-Hunt, Shannon L.; Bartz, Jason C.
2012-01-01
Before prion uptake and infection can occur in the lower gastrointestinal system, ingested prions are subjected to anaerobic digestion in the rumen of cervids and bovids. The susceptibility of soil-bound prions to rumen digestion has not been evaluated previously. In this study, prions from infectious brain homogenates as well as prions bound to a range of soils and soil minerals were subjected to in vitro rumen digestion, and changes in PrP levels were measured via western blot. Binding to clay appeared to protect noninfectious hamster PrPc from complete digestion, while both unbound and soil-bound infectious PrPSc proved highly resistant to rumen digestion. In addition, no change in intracerebral incubation period was observed following active rumen digestion of unbound hamster HY TME prions and HY TME prions bound to a silty clay loam soil. These results demonstrate that both unbound and soil-bound prions readily survive rumen digestion without a reduction in infectivity, further supporting the potential for soil-mediated transmission of chronic wasting disease (CWD) and scrapie in the environment. PMID:22937149
Upper bound of abutment scour in laboratory and field data
Benedict, Stephen
2016-01-01
The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted a field investigation of abutment scour in South Carolina and used those data to develop envelope curves that define the upper bound of abutment scour. To expand on this previous work, an additional cooperative investigation was initiated to combine the South Carolina data with abutment scour data from other sources and evaluate upper bound patterns with this larger data set. To facilitate this analysis, 446 laboratory and 331 field measurements of abutment scour were compiled into a digital database. This extensive database was used to evaluate the South Carolina abutment scour envelope curves and to develop additional envelope curves that reflected the upper bound of abutment scour depth for the laboratory and field data. The envelope curves provide simple but useful supplementary tools for assessing the potential maximum abutment scour depth in the field setting.
Cell wall bound anionic peroxidases from asparagus byproducts.
Jaramillo-Carmona, Sara; López, Sergio; Vazquez-Castilla, Sara; Jimenez-Araujo, Ana; Rodriguez-Arcos, Rocio; Guillen-Bejarano, Rafael
2014-10-08
Asparagus byproducts are a good source of cationic soluble peroxidases (CAP) useful for the bioremediation of phenol-contaminated wastewaters. In this study, cell wall bound peroxidases (POD) from the same byproducts have been purified and characterized. The covalent forms of POD represent >90% of the total cell wall bound POD. Isoelectric focusing showed that whereas the covalent fraction is constituted primarily by anionic isoenzymes, the ionic fraction is a mixture of anionic, neutral, and cationic isoenzymes. Covalently bound peroxidases were purified by means of ion exchange chromatography and affinity chromatography. In vitro detoxification studies showed that although CAP are more effective for the removal of 4-CP and 2,4-DCP, anionic asparagus peroxidase (AAP) is a better option for the removal of hydroxytyrosol (HT), the main phenol present in olive mill wastewaters.
Ecological optimization and coefficient of performance bounds of general refrigerators
Long, Rui; Liu, Wei
2016-02-01
An analysis of COP and its bounds at maximum ecological criterion for general refrigerators is conducted. For generality, both the non-isothermal heat transfer processes and the internal dissipations are considered. Under different situations, the COP under the maximum ecological criterion have been studied systematically. And the general upper and lower bounds of the optimal COP have been obtained. Furthermore under maximum ecological criterion, the COP of general endoreversible refrigerators have also been studied. And the COP bounds of different kinds of refrigerators have been analyzed. As actual refrigerators may not operate under the condition of maximum COP or maximum cooling load, but operate under the maximum ecological condition which indicates the best compromise between the refrigeration rate and the loss of refrigeration rate. This paper could provide a practical insight for designing and operating actual refrigerators.
Research on Bounded Rationality of Fuzzy Choice Functions
Directory of Open Access Journals (Sweden)
Xinlin Wu
2014-01-01
Full Text Available The rationality of a fuzzy choice function is a hot research topic in the study of fuzzy choice functions. In this paper, two common fuzzy sets are studied and analyzed in the framework of the Banerjee choice function. The complete rationality and bounded rationality of fuzzy choice functions are defined based on the two fuzzy sets. An assumption is presented to study the fuzzy choice function, and especially the fuzzy choice function with bounded rationality is studied combined with some rationality conditions. Results show that the fuzzy choice function with bounded rationality also satisfies some important rationality conditions, but not vice versa. The research gives supplements to the investigation in the framework of the Banerjee choice function.
Life-time of the bound layer in nanocomposites
Zhao, Dan; Jestin, Jacques; Kumar, Sanat K.
2015-03-01
It is now well accepted that an effectively irreversibly adsorbed monolayer of polymer forms when a polymer melt is intimately mixed with nanoparticles, in the limit where their enthalpic interactions are favorable. This bound layer has been postulated as being a central player in many of the highly favorable properties that result from polymer based nanocomposite materials. We investigated well-defined nanocomposites formed with different combinations of deuterated and hydrogenated polymers (P2VP and PMMA) and silica nanoparticles. SANS, in conjunction with contrast variation, then provides a direct means of probing the structure of the bound layer as a core-shell and its exchange kinetics with bulk (unbound) chains with annealing time and temperature. SAXS directly provides information on the particle-particle partial structure factor and particle dispersion. Thermodynamic equilibrium of the bound layer is reached around one day at 150 °C while its exchange life time is ~ one hour at 180 °C.
Properties of a Bound Polaron under a Perpendicular Magnetic Field
International Nuclear Information System (INIS)
Liu Jia; Chen Ziyu; Xiao Jinglin; Huo Shufen
2007-01-01
We investigate the influence of a perpendicular magnetic field on a bound polaron near the interface of a polar-polar semiconductor with Rashba effect. The external magnetic field strongly changes the ground state binding energy of the polaron and the Rashba spin-orbit (SO) interaction originating from the inversion asymmetry in the heterostructure splits the ground state binding energy of the bound polaron. In this paper, we have shown how the ground state binding energy will be with the change of the external magnetic field, the location of a single impurity, the wave vector of the electron and the electron areal density, taking into account the SO coupling. Due to the presence of the phonons, whose energy gives negative contribution to the polaron's, the spin-splitting states of the bound polaron are more stable, and we find that in the condition of week magnetic field, the Zeeaman effect can be neglected.
Error bounds for two even degree tridiagonal splines
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Gary W. Howell
1990-01-01
Full Text Available We study a C(1 parabolic and a C(2 quartic spline which are determined by solution of a tridiagonal matrix and which interpolate subinterval midpoints. In contrast to the cubic C(2 spline, both of these algorithms converge to any continuous function as the length of the largest subinterval goes to zero, regardless of mesh ratios. For parabolic splines, this convergence property was discovered by Marsden [1974]. The quartic spline introduced here achieves this convergence by choosing the second derivative zero at the breakpoints. Many of Marsden's bounds are substantially tightened here. We show that for functions of two or fewer coninuous derivatives the quartic spline is shown to give yet better bounds. Several of the bounds given here are optimal.
Performance bounds on parallel self-initiating discrete-event
Nicol, David M.
1990-01-01
The use is considered of massively parallel architectures to execute discrete-event simulations of what is termed self-initiating models. A logical process in a self-initiating model schedules its own state re-evaluation times, independently of any other logical process, and sends its new state to other logical processes following the re-evaluation. The interest is in the effects of that communication on synchronization. The performance is considered of various synchronization protocols by deriving upper and lower bounds on optimal performance, upper bounds on Time Warp's performance, and lower bounds on the performance of a new conservative protocol. The analysis of Time Warp includes the overhead costs of state-saving and rollback. The analysis points out sufficient conditions for the conservative protocol to outperform Time Warp. The analysis also quantifies the sensitivity of performance to message fan-out, lookahead ability, and the probability distributions underlying the simulation.
Bounds on the average sensitivity of nested canalizing functions.
Directory of Open Access Journals (Sweden)
Johannes Georg Klotz
Full Text Available Nested canalizing Boolean functions (NCF play an important role in biologically motivated regulatory networks and in signal processing, in particular describing stack filters. It has been conjectured that NCFs have a stabilizing effect on the network dynamics. It is well known that the average sensitivity plays a central role for the stability of (random Boolean networks. Here we provide a tight upper bound on the average sensitivity of NCFs as a function of the number of relevant input variables. As conjectured in literature this bound is smaller than 4/3. This shows that a large number of functions appearing in biological networks belong to a class that has low average sensitivity, which is even close to a tight lower bound.
Bounds on the average sensitivity of nested canalizing functions.
Klotz, Johannes Georg; Heckel, Reinhard; Schober, Steffen
2013-01-01
Nested canalizing Boolean functions (NCF) play an important role in biologically motivated regulatory networks and in signal processing, in particular describing stack filters. It has been conjectured that NCFs have a stabilizing effect on the network dynamics. It is well known that the average sensitivity plays a central role for the stability of (random) Boolean networks. Here we provide a tight upper bound on the average sensitivity of NCFs as a function of the number of relevant input variables. As conjectured in literature this bound is smaller than 4/3. This shows that a large number of functions appearing in biological networks belong to a class that has low average sensitivity, which is even close to a tight lower bound.
Model independent bounds on magnetic moments of Majorana neutrinos
International Nuclear Information System (INIS)
Bell, Nicole F.; Gorchtein, Mikhail; Ramsey-Musolf, Michael J.; Vogel, Petr; Wang, Peng
2006-01-01
We analyze the implications of neutrino masses for the magnitude of neutrino magnetic moments. By considering electroweak radiative corrections to the neutrino mass, we derive model-independent naturalness upper bounds on neutrino magnetic moments, μ ν , generated by physics above the electroweak scale. For Dirac neutrinos, the bound is several orders of magnitude more stringent than present experimental limits. However, for Majorana neutrinos the magnetic moment contribution to the mass is Yukawa suppressed. The bounds we derive for magnetic moments of Majorana neutrinos are weaker than present experimental limits if μ ν is generated by new physics at ∼1 TeV, and surpass current experimental sensitivity only for new physics scales >10-100 TeV. The discovery of a neutrino magnetic moment near present limits would thus signify that neutrinos are Majorana particles
Bounds for the propagation speed of combustion flames
International Nuclear Information System (INIS)
Fort, Joaquim; Campos, Daniel; Gonzalez, Josep R; Velayos, Joaquim
2004-01-01
We focus on a combustion model for premixed flames based on two coupled equations determining the spatial dynamics of temperature and fuel density. We rewrite these equations as a classical reaction-diffusion model, so that we can apply some known methods for the prediction of lower and upper bounds to the front speed. The predictions are compared to simulations, which show that our new bounds substantially improve those following from the linearization method, used in the previous work of Fort et al (2000 J. Phys. A: Math. Gen. 33 6953). Radiative losses lead to pulses rather than fronts. We find a bound for their speed which (in contrast to the linearization one) correctly predicts the order of magnitude of the flame speed
Relativistic bound state approach to fundamental forces including gravitation
Directory of Open Access Journals (Sweden)
Morsch H.P.
2012-06-01
Full Text Available To describe the structure of particle bound states of nature, a relativistic bound state formalism is presented, which requires a Lagrangian including scalar coupling of two boson fields. The underlying mechanisms are quite complex and require an interplay of overlapping boson fields and fermion-antifermion production. This gives rise to two potentials, a boson-exchange potential and one identified with the long sought confinement potential in hadrons. With minimal requirements, two elementary massless fermions (quantons - with and without charge - and one gauge boson, hadrons and leptons but also atoms and gravitational systems are described by bound states with electric and magnetic coupling between the charges and spins of quantons. No need is found for colour, Higgs-coupling and supersymmetry.
Soft-bound synaptic plasticity increases storage capacity.
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Mark C W van Rossum
Full Text Available Accurate models of synaptic plasticity are essential to understand the adaptive properties of the nervous system and for realistic models of learning and memory. Experiments have shown that synaptic plasticity depends not only on pre- and post-synaptic activity patterns, but also on the strength of the connection itself. Namely, weaker synapses are more easily strengthened than already strong ones. This so called soft-bound plasticity automatically constrains the synaptic strengths. It is known that this has important consequences for the dynamics of plasticity and the synaptic weight distribution, but its impact on information storage is unknown. In this modeling study we introduce an information theoretic framework to analyse memory storage in an online learning setting. We show that soft-bound plasticity increases a variety of performance criteria by about 18% over hard-bound plasticity, and likely maximizes the storage capacity of synapses.
Requirement of system-reservoir bound states for entanglement protection
Behzadi, N.; Ahansaz, B.; Faizi, E.; Kasani, H.
2018-03-01
In this work, a genuine mechanism for entanglement protection of a two- qubit system interacting with a dissipative common reservoir is investigated. Based on generating a bound state for the system-reservoir, we show that stronger bound state in the energy spectrum can be created by adding another non-interacting qubits into the reservoir. It turns out that obtaining higher degrees of boundedness in the energy spectrum leads to a better protection of two-qubit entanglement against the dissipative noises. Also, it is figured out that the formation of bound state not only exclusively determines the long-time entanglement protection, irrespective to the Markovian and non-Markovian dynamics, but also performs the same task for reservoirs with different spectral densities.
Culture-bound syndromes: the story of dhat syndrome.
Sumathipala, A; Siribaddana, S H; Bhugra, Dinesh
2004-03-01
Culture-bound syndrome is a term used to describe the uniqueness of some syndromes in specific cultures. Dhat (semen-loss anxiety) has been considered to be an exotic 'neurosis of the Orient'. To ascertain the presence of similar symptoms and syndromes in different cultures and historical settings. Electronic and manual literature searches were used to gather information on the existence and description of semen-loss anxiety in different cultures and settings. Most of the empirical studies on dhat syndrome have emerged from Asia, whereas its concepts have been described historically in other cultures, including Britain, the USA and Australia. The different sources indicate the universality of symptoms and global prevalence of this condition, despite its image as a 'neurosis of the Orient'. It appears that dhat (semen-loss anxiety) is not as culture-bound as previously thought. We propose that the concept of culture-bound syndromes should be modified in line with DSM-IV recommendations.
PENERAPAN BRANCH AND BOUND ALGORITHM DALAM OPTIMALISASI PRODUKSI ROTI
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GEDE SURYAWAN
2016-11-01
Full Text Available Companies which engaged in production activities such as Ramadhan Bakery would want optimal profit in their every production. The aim of this study was to find optimal profit and optimal combination of bread production (original chocolate bread, extra chocolate bread, rounding chocolate bread and mattress chocolate bread that was produced by Ramadhan Bakery by applying Branch and Bound Algorithm method. Branch and Bound Algorithm is one method to solve Integer Programming’s problems other than Cutting Plane method. Compared with Cutting Plane method, Branch and Bound Algorithm method is more effective in determining the optimal value. As the result of this study showed that to get optimal profit, Ramadhan Bakery should produce 360 pcs of original chocolate bread, 300 pcs of extra chocolate bread, 306 pcs of rounding chocolate bread and 129 pcs of mattress chocolate bread with optimal profit amounts Rp. 1.195.624,00.. The profit will increase amounts 25,2 % than before.
A geometrical origin for the covariant entropy bound
Casini, H.
2003-07-01
Causal diamond-shaped subsets of spacetime are naturally associated with operator algebras in quantum field theory, and they are also related to the Bousso covariant entropy bound. In this work we argue that the net of these causal sets to which are assigned the local operator algebras of quantum theories should be taken to be non-orthomodular if there is some lowest scale for the description of spacetime as a manifold. This geometry can be related to a reduction in the degrees of freedom of the holographic type under certain natural conditions for the local algebras. A non-orthomodular net of causal sets that implements the cutoff in a covariant manner is constructed. It gives an explanation, in a simple example, of the non-positive expansion condition for lightsheet selection in the covariant entropy bound. It also suggests a different covariant formulation of the entropy bound.
A geometrical origin for the covariant entropy bound
Energy Technology Data Exchange (ETDEWEB)
Casini, H [Centre de Physique Theorique, Campus de Luminy, F-13288 Marseille (France)
2003-07-07
Causal diamond-shaped subsets of spacetime are naturally associated with operator algebras in quantum field theory, and they are also related to the Bousso covariant entropy bound. In this work we argue that the net of these causal sets to which are assigned the local operator algebras of quantum theories should be taken to be non-orthomodular if there is some lowest scale for the description of spacetime as a manifold. This geometry can be related to a reduction in the degrees of freedom of the holographic type under certain natural conditions for the local algebras. A non-orthomodular net of causal sets that implements the cutoff in a covariant manner is constructed. It gives an explanation, in a simple example, of the non-positive expansion condition for lightsheet selection in the covariant entropy bound. It also suggests a different covariant formulation of the entropy bound.
Lower Bounds in the Asymmetric External Memory Model
DEFF Research Database (Denmark)
Jacob, Riko; Sitchinava, Nodari
2017-01-01
Motivated by the asymmetric read and write costs of emerging non-volatile memory technologies, we study lower bounds for the problems of sorting, permuting and multiplying a sparse matrix by a dense vector in the asymmetric external memory model (AEM). Given an AEM with internal (symmetric) memory...... of size M, transfers between symmetric and asymmetric memory in blocks of size B and the ratio ω between write and read costs, we show Ω(min (N, ωN/B logω M/B N/B) lower bound for the cost of permuting N input elements. This lower bound also applies to the problem of sorting N elements. This proves...
Faddeev-Yakubovsky technique for weakly bound systems
International Nuclear Information System (INIS)
Hadizadeh, M.R.; Yamashita, M.T.; Tomio, Lauro; Delfino, A.
2011-01-01
Nature shows the existence of weakly bound systems in different sectors, ranging from atomic to nuclear physics. Few-body systems with large scattering length exhibit universal features, which are independent of the details of the interaction, and thus are common to nuclear and atomic systems. Very different methods are used to study the properties of few-body systems, from Faddeev methods to diagonalization methods that rely on an expansion of the wave functions in a complete basis set, like e.g. hyper-spherical harmonics and no core shell model. In this talk we present Faddeev-Yakubovsky method to study the three- and four-body bound states in momentum space. To show the efficiency and accuracy of the method we investigate the three- and four-boson weakly bound states in unitary limit (for zero two-body binding) and we present a pretty complete picture of universality. (author)
Viscosity bound for anisotropic superfluids in higher derivative gravity
Energy Technology Data Exchange (ETDEWEB)
Bhattacharyya, Arpan; Roychowdhury, Dibakar [Centre for High Energy Physics, Indian Institute of Science,C.V. Raman Avenue, Bangalore 560012 (India)
2015-03-11
In the present paper, based on the principles of gauge/gravity duality we analytically compute the shear viscosity to entropy (η/s) ratio corresponding to the super fluid phase in Einstein Gauss-Bonnet gravity. From our analysis we note that the ratio indeed receives a finite temperature correction below certain critical temperature (T
Multitask Classification Hypothesis Space With Improved Generalization Bounds.
Li, Cong; Georgiopoulos, Michael; Anagnostopoulos, Georgios C
2015-07-01
This paper presents a pair of hypothesis spaces (HSs) of vector-valued functions intended to be used in the context of multitask classification. While both are parameterized on the elements of reproducing kernel Hilbert spaces and impose a feature mapping that is common to all tasks, one of them assumes this mapping as fixed, while the more general one learns the mapping via multiple kernel learning. For these new HSs, empirical Rademacher complexity-based generalization bounds are derived, and are shown to be tighter than the bound of a particular HS, which has appeared recently in the literature, leading to improved performance. As a matter of fact, the latter HS is shown to be a special case of ours. Based on an equivalence to Group-Lasso type HSs, the proposed HSs are utilized toward corresponding support vector machine-based formulations. Finally, experimental results on multitask learning problems underline the quality of the derived bounds and validate this paper's analysis.
Culture-bound syndromes in Hispanic primary care patients.
Bayles, Bryan P; Katerndahl, David A
2009-01-01
We sought to document Hispanic primary care patients' knowledge and experience of five culture-bound syndromes (CBS), as well as the basic socio-cultural correlates of these disorders. A convenience sample of 100 adult Hispanic patients presenting in an urban South Texas primary care clinic was recruited to complete a brief cross-sectional survey, presented in an oral format. Interviews sought information concerning five culture-bound syndromes--susto, empacho, nervios, mal de ojo, and ataques de nervios. Additional demographic, socio-economic, and acculturation data was collected. Descriptive and bivariate statistics (chi square, Fisher's) were used to assess relationships among variables and experience with each CBS. A multivariate logistic analysis was conducted to determine the possible contributions of age, gender, acculturation, and education to the personal experience of a culture-bound syndrome. Results indicate that 77% of respondents had knowledge of all five syndromes, with 42% reporting having personally experienced at least one CBS. Nervios was the most commonly suffered disorder, being reported by 30 respondents. This was followed, in declining order ofprevalence, by susto, mal de ojo, empacho, and ataques de nervios. Multivariate logistic regression analysis found that higher education beyond high school was associated with a slightly decreased likelihood of reporting having suffered from any culture-bound syndrome. While co-occurrence among these disorders occurred, the patterns of predictors suggest that the co-occurrence is not a reflection of mislabeling of one common syndrome. Knowledge of and experience with culture-bound syndromes is common among Hispanic primary care patients in South Texas. Healthcare providers ought to consider discussing these illnesses in a non-judgmental manner with patients who present with symptoms that are consistent with these syndromes. Future studies, with larger sample sizes, are warranted to elucidate the nature
Bounds on stratified mixing with a mixing coefficient constraint
Tang, Wenbo; Caulfield, C. P.; Kerswell, Rich
2005-11-01
We derive non-trivial upper bounds for the long-time averaged vertical buoyancy flux B^* = ρu3>g/ρ0 for stably stratified Couette flow, with reference density ρ0, kinematic viscosity ν, thermal diffusivity κ, plate separation d, driven by constant relative velocity δU, maintained at a statically stable density difference δρ. We numerically solve the variational problem using the ``background method'', and require that the mean flow is streamwise independent and statistically steady. We impose a coupling constraint such that a fixed fraction γc of the energy input into the system leads to enhanced irreversible mixing. We calculate the bound up to asymptotically large Reynolds numbers for a range of choices of γc and bulk Richardson numbers J. For any Re, the calculated upper bound increases with J, until a maximum possible value J(Re,γc) at which the new constraint cannot be imposed, and the density field and velocity field become decoupled. The value of the bound at J is a non-monotonic function of γc, with γc=1/2 leading to the largest possible values as Re , consistently with the findings in Caulfield, Tang & Plasting (2004) where this coupling constraint was not imposed. In fact, at any particular Re, the previous solution may be associated with a specific value of γc. Imposing the coupling constraint with that γc, as J , the new bound approaches from below the previous bound exactly.
On weighted spaces without a fundamental sequence of bounded sets
International Nuclear Information System (INIS)
Olaleru, J.O.
2001-09-01
The problem of countably quasibarrelledness of weighted spaces of continuous functions, of which there are no results in the general setting of weighted spaces, is tackled in this paper. This leads to the study of quasibarrelledness of weighted spaces which, unlike that of Ernst and Schnettler, though with a similar approach, we drop the assumption that the weighted space has a fundamental sequence of bounded sets. The study of countably quasibarrelledness of weighted spaces naturally leads to definite results on the weighted (DF)-spaces for those weighted spaces with a fundamental sequence of bounded sets. (author)
Vulnerable Derivatives and Good Deal Bounds: A Structural Model
DEFF Research Database (Denmark)
Murgoci, Agatha
2013-01-01
We price vulnerable derivatives -- i.e. derivatives where the counterparty may default. These are basically the derivatives traded on the over-the-counter (OTC) markets. Default is modeled in a structural framework. The technique employed for pricing is good deal bounds (GDBs). The method imposes...... can be obtained. We provide a link between the objective probability measure and the range of potential risk-neutral measures, which has an intuitive economic meaning. We also provide tight pricing bounds for European calls and show how to extend the call formula to pricing other financial products...
First observation of bound-state β-decay
International Nuclear Information System (INIS)
Jung, M.; Bosch, F.; Beckert, K.; Eickhoff, H.; Folger, H.; Franzke, B.; Kienle, P.; Klepper, O.; Koenig, W.; Kozhuharov, C.; Mann, R.; Moshammer, R.; Nolden, F.; Schaaf, U.; Soff, G.; Spaedtke, P.; Steck, M.; Stoehlker, T.; Suemmerer, K.
1992-06-01
Bound-state Β - decay was observed for the first time by storing bare 66 163 Dy 66+ ions in a heavy-ion storage ring. From the number of 67 163 Ho 66+ daughter ions, measured as a function of the storage time, a half-life of 47 4 +5 - d was derived. By comparing this result with reported half-lives for electron capture (EC) from the M 1 and M 2 shells of neutral 67 163 Ho, bounds for both the Q EC value of neutral 67 163 Ho and for the electron neutrino mass were set. (orig.)
Universal extra dimensions and Kaluza-Klein bound states
International Nuclear Information System (INIS)
Carone, Christopher D.; Conroy, Justin M.; Sher, Marc; Turan, Ismail
2004-01-01
We study the bound states of the Kaluza-Klein (KK) excitations of quarks in certain models of universal extra dimensions. Such bound states may be detected at future lepton colliders in the cross section for the pair production of KK quarks near threshold. For typical values of model parameters, we find that 'KK quarkonia' have widths in the 10-100 MeV range, and production cross sections of the order of a few picobarns for the lightest resonances. Two body decays of the constituent KK quarks lead to distinctive experimental signatures. We point out that such KK resonances may be discovered before any of the higher KK modes
Atomic Stretch: Optimally bounded real-time stretching and beyond
DEFF Research Database (Denmark)
Jensen, Rasmus Ramsbøl; Nielsen, Jannik Boll
2016-01-01
Atomic Stretch is a plugin for your preferred Adobe video editing tool, allowing real-time smooth and optimally bounded retarget-ting from and to any aspect ratio. The plugin allows preserving of high interest pixels through a protected region, attention redirection through color-modification, co......Atomic Stretch is a plugin for your preferred Adobe video editing tool, allowing real-time smooth and optimally bounded retarget-ting from and to any aspect ratio. The plugin allows preserving of high interest pixels through a protected region, attention redirection through color...
Bionic Control of Cheetah Bounding with a Segmented Spine
Wang, Chunlei; Wang, Shigang
2016-01-01
A cheetah model is built to mimic real cheetah and its mechanical and dimensional parameters are derived from the real cheetah. In particular, two joints in spine and four joints in a leg are used to realize the motion of segmented spine and segmented legs which are the key properties of the cheetah bounding. For actuating and stabilizing the bounding gait of cheetah, we present a bioinspired controller based on the state-machine. The controller mainly mimics the function of the cerebellum to...
Computed bound and continuum electronic states of the nitrogen molecule
Directory of Open Access Journals (Sweden)
Tennyson Jonathan
2015-01-01
Full Text Available The dissociative recombination (DR of N2+ is important for processes occurring in our atmosphere. However, it is not particularly well characterised, experimentally for the vibrational ground state and, theoretically for the v ≥ 4. We use the R-matrix method to compute potential energy curves for both the bound Rydberg states of nitrogen and for quasi-bound states lying in the continuum. Use of a fine mesh of internuclear separations allows the details of avoided crossings to be determined. The prospects for using the curves as the input for DR calculations is discussed.
Upper bounds for Neyman-Pearson cooperative spectrum sensing
Zahabi, Sayed Jalal
2011-06-01
We consider a cooperative spectrum sensing scenario where the local sensors at the secondary users are viewed as one-level quantizers, and the quantized data are to be fused under Neyman-Pearson (N-P) criterion. We demonstrate how the N-P fusion results in a randomized test, which represents the total performance of our spectrum sensing scheme. We further introduce an upper performance bound for the overall primary user signal detection. An analytical procedure towards the upper bound and its relevant quantization setup at the local sensors are proposed and examined through simulations. © 2011 IEEE.
Unitarity bounds on angular distribution in multiparticle production - II
International Nuclear Information System (INIS)
Divakaran, P.P.; Kugler, M.; Soffer, J.
1976-01-01
Upper bounds which follow from unitarity are derived for the angular distribution of the detected particle C in the inclusive process AB→C+anything at a finite energy, in terms of the corresponding elastic amplitudes for a fixed value of the forward inelastic cross-section and for a fixed value of the total inelastic cross-section for the production of C. In comparison with the pp→p+anything data at 24GeV/c, some improvement on previous bounds is observed [fr
Positive energy bound states at higher partial waves
International Nuclear Information System (INIS)
Awin, A.M.; Kremid, A.M.
1988-06-01
Positive energy bound states (PEBS) at higher order (than the 0 th ) partial waves have been studied using a particular form factor. The phase shifts have been calculated in detail for the cases of l=0,1,2. It is found that for a rank-1 separable potential the expected behaviour, at the PEBS energy, is obtained. Finally, some important conclusions have been drawn regarding some problems previously studied in connection with s-wave positive energy bound states. (author). 8 refs, 3 figs
Sharp Bounds by Probability-Generating Functions and Variable Drift
DEFF Research Database (Denmark)
Doerr, Benjamin; Fouz, Mahmoud; Witt, Carsten
2011-01-01
We introduce to the runtime analysis of evolutionary algorithms two powerful techniques: probability-generating functions and variable drift analysis. They are shown to provide a clean framework for proving sharp upper and lower bounds. As an application, we improve the results by Doerr et al....... (GECCO 2010) in several respects. First, the upper bound on the expected running time of the most successful quasirandom evolutionary algorithm for the OneMax function is improved from 1.28nln n to 0.982nlnn, which breaks the barrier of nln n posed by coupon-collector processes. Compared to the classical...
Analytical solution of relativistic three-body bound systems
Energy Technology Data Exchange (ETDEWEB)
Aslanzadeh, M.; Rajabi, A.A. [Shahrood University of Technology, Physics Department, Shahrood (Iran, Islamic Republic of)
2014-10-15
In this paper we have investigated in detail the relativistic three-body bound states. We carried out calculations in six-dimensional representation on the basis of the Jacobi coordinates. The obtained second-degree differential equation is solved by using the Nikiforov-Uvarov method and the energy eigenvalues are obtained. Consequently we obtained the binding energy of the three-nucleon bound system. Here we used the generalized Woods-Saxon spin-independent potential in our calculations. The dependence of the three-body binding energy on the potential parameters is also investigated. (orig.)
Bioavailability of sediment-bound contaminants to marine organisms
Energy Technology Data Exchange (ETDEWEB)
Brown, B. [Battelle/Marine Sciences Lab., Sequim, WA (United States)]|[Colby Coll., Waterville, ME (United States); Neff, J. [Battelle/Marine Sciences Lab., Sequim, WA (United States)]|[Battelle Ocean Sciences, Duxbury, MA (United States)
1993-09-01
The bioavailability of sediment-bound contaminants to marine organisms indicates that there exists a potential for transfer of these contaminants through marine food webs to commercial fisheries products consumed by humans. However, there has been relatively little effort to combine and synthesize data on chemical/biological interactions between benthic animals and seagrasses and the sediments in which they reside on the one hand, and on the chemistry of bioaccumulation on the other. This report provides a conceptual basis for an approach to bioavailability and biomagnification of sediment-bound contaminants that reviews biological and chemical approaches.
Simplified Drift Analysis for Proving Lower Bounds in Evolutionary Computation
DEFF Research Database (Denmark)
Oliveto, Pietro S.; Witt, Carsten
2011-01-01
Drift analysis is a powerful tool used to bound the optimization time of evolutionary algorithms (EAs). Various previous works apply a drift theorem going back to Hajek in order to show exponential lower bounds on the optimization time of EAs. However, this drift theorem is tedious to read and to...... involving the complicated theorem can be redone in a much simpler and clearer way. In some cases even improved results may be achieved. Therefore, the simplified theorem is also a didactical contribution to the runtime analysis of EAs....
Thermodynamic Bounds on Precision in Ballistic Multiterminal Transport
Brandner, Kay; Hanazato, Taro; Saito, Keiji
2018-03-01
For classical ballistic transport in a multiterminal geometry, we derive a universal trade-off relation between total dissipation and the precision, at which particles are extracted from individual reservoirs. Remarkably, this bound becomes significantly weaker in the presence of a magnetic field breaking time-reversal symmetry. By working out an explicit model for chiral transport enforced by a strong magnetic field, we show that our bounds are tight. Beyond the classical regime, we find that, in quantum systems far from equilibrium, the correlated exchange of particles makes it possible to exponentially reduce the thermodynamic cost of precision.
A new branch and bound algorithm for minimax ratios problems
Directory of Open Access Journals (Sweden)
Zhao Yingfeng
2017-06-01
Full Text Available This study presents an efficient branch and bound algorithm for globally solving the minimax fractional programming problem (MFP. By introducing an auxiliary variable, an equivalent problem is firstly constructed and the convex relaxation programming problem is then established by utilizing convexity and concavity of functions in the problem. Other than usual branch and bound algorithm, an adapted partition skill and a practical reduction technique performed only in an unidimensional interval are incorporated into the algorithm scheme to significantly improve the computational performance. The global convergence is proved. Finally, some comparative experiments and a randomized numerical test are carried out to demonstrate the efficiency and robustness of the proposed algorithm.
Generalized mutual information and Tsirelson's bound
Energy Technology Data Exchange (ETDEWEB)
Wakakuwa, Eyuri [Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo 113-0033 (Japan); Murao, Mio [Institute for Nano Quantum Information Electronics, The University of Tokyo, Tokyo 113-0033, Japan and Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo 113-0033 (Japan)
2014-12-04
We introduce a generalization of the quantum mutual information between a classical system and a quantum system into the mutual information between a classical system and a system described by general probabilistic theories. We apply this generalized mutual information (GMI) to a derivation of Tsirelson's bound from information causality, and prove that Tsirelson's bound can be derived from the chain rule of the GMI. By using the GMI, we formulate the 'no-supersignalling condition' (NSS), that the assistance of correlations does not enhance the capability of classical communication. We prove that NSS is never violated in any no-signalling theory.
Enhanced desorption of humin-bound phenanthrene by attached phenanthrene-degrading bacteria.
Zhang, Yinping; Wang, Fang; Bian, Yongrong; Kengara, Fredrick Orori; Gu, Chenggang; Zhao, Qiguo; Jiang, Xin
2012-11-01
The objective of the study was to test the hypothesis that the attachment of polycyclic aromatic hydrocarbons (PAHs)-degrading bacteria can promote desorption of PAHs from humin, thereby increasing their bioavailability. Biodegradation of humin-bound phenanthrene (PHE) - a model compound for PAHs - was investigated using two PHE-degrading bacteria, Sphingobium sp. PHE3 and Micrococcus sp. PHE9, respectively. Sorption data of PHE to humin fitted well into the modified Freundlich equation. Further, a new sorption band appeared at 1262cm(-1), demonstrating intermolecular interactions between PHE and humin. Interestingly, approximately 65.3% of humin-bound PHE was degraded by both strains, although only about 17.8% of PHE could be desorbed from humin by Tenax extraction. Furthermore, both strains grew well in mineral medium and also attached to humin surfaces for substrate uptake. It is proposed that the attached bacteria could possibly consume PHE on the humin via interactions between bacterial surfaces and humin, thereby overcoming the low PHE bioavailability and resulting in enhanced degradation. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.
Approximate parameter synthesis for probabilistic time-bounded reachability
Han, Tingting; Katoen, Joost P.; Mereacre, A.
2008-01-01
This paper proposes a technique to synthesize parametric rate values in continuous-time Markov chains that ensure the validity of bounded reachability properties. Rate expressions over variables indicate the average speed of state changes and are expressed using the polynomials over reals. The key
Bounds on the hop domination number of a tree
Indian Academy of Sciences (India)
Combinatorial Math. Combinatorial Computing 58 (2006) 189–193. [2] Krzywkowski M, A lower bound on the total outer-independent domination of a tree,. Comptes Rendus Mathematique 349 (2011) 7–9. [3] Haynes T, Hedetniemi S and Slater P, Fundamentals of Domination in Graphs (1998). (New York: Marcel Dekker).
Stability and response bounds of non-conservative linear systems
DEFF Research Database (Denmark)
Kliem, Wolfhard; Pommer, Christian
2004-01-01
This paper develops a stability theorem and response bounds for non-conservative systems of the form MX + (D + G)x + (K + N)x = f(t), with hermitian positive-definite matrices M, D and K, and skew-hermitian matrices G and N. To this end, we first find a Lyapunov function by solving the Lyapunov m...
Volume dependence of N-body bound states
König, Sebastian; Lee, Dean
2018-04-01
We derive the finite-volume correction to the binding energy of an N-particle quantum bound state in a cubic periodic volume. Our results are applicable to bound states with arbitrary composition and total angular momentum, and in any number of spatial dimensions. The only assumptions are that the interactions have finite range. The finite-volume correction is a sum of contributions from all possible breakup channels. In the case where the separation is into two bound clusters, our result gives the leading volume dependence up to exponentially small corrections. If the separation is into three or more clusters, there is a power-law factor that is beyond the scope of this work, however our result again determines the leading exponential dependence. We also present two independent methods that use finite-volume data to determine asymptotic normalization coefficients. The coefficients are useful to determine low-energy capture reactions into weakly bound states relevant for nuclear astrophysics. Using the techniques introduced here, one can even extract the infinite-volume energy limit using data from a single-volume calculation. The derived relations are tested using several exactly solvable systems and numerical examples. We anticipate immediate applications to lattice calculations of hadronic, nuclear, and cold atomic systems.
Immunoglobulin G bound to ovine placenta is eluted by surgical ...
African Journals Online (AJOL)
Objective: To elute placental bound immunoglobulin G (IgG) in situ. Design: Laboratory based experimentation. Setting: Biological Sciences Department, The University of Newcastle Australia and the Department of Biochemistry, University of Nairobi, Kenya. Subjects: Twelve pregnant ewes 10 to 15 days before the onset of ...
Scaling properties of net information measures for bound states of ...
Indian Academy of Sciences (India)
Using dimensional analyses, the scaling properties of the Heisenberg uncertainty relationship as well as the various information theoretical uncertainty-like relationships are derived for the bound states corresponding to the superposition of the power potential of the form () = + $^{n_{i}}, where , , , ...
Improved endpoint bounds for the lacunary spherical maximal operator
Cladek, Laura; Krause, Ben
2017-01-01
We prove new endpoint bounds for the lacunary spherical maximal operator and as a consequence obtain almost everywhere pointwise convergence of lacunary spherical means for functions locally in $L\\log\\log\\log L(\\log\\log\\log\\log L)^{1+\\epsilon}$ for any $\\epsilon>0$.
Scaling Limits and Generic Bounds for Exploration Processes
Bermolen, Paola; Jonckheere, Matthieu; Sanders, Jaron
2017-12-01
We consider exploration algorithms of the random sequential adsorption type both for homogeneous random graphs and random geometric graphs based on spatial Poisson processes. At each step, a vertex of the graph becomes active and its neighboring nodes become blocked. Given an initial number of vertices N growing to infinity, we study statistical properties of the proportion of explored (active or blocked) nodes in time using scaling limits. We obtain exact limits for homogeneous graphs and prove an explicit central limit theorem for the final proportion of active nodes, known as the jamming constant, through a diffusion approximation for the exploration process which can be described as a unidimensional process. We then focus on bounding the trajectories of such exploration processes on random geometric graphs, i.e., random sequential adsorption. As opposed to exploration processes on homogeneous random graphs, these do not allow for such a dimensional reduction. Instead we derive a fundamental relationship between the number of explored nodes and the discovered volume in the spatial process, and we obtain generic bounds for the fluid limit and jamming constant: bounds that are independent of the dimension of space and the detailed shape of the volume associated to the discovered node. Lastly, using coupling techinques, we give trajectorial interpretations of the generic bounds.
Scaling properties of net information measures for bound states of ...
Indian Academy of Sciences (India)
located at radius R The uncertainty product and all other net information measures are shown here to depend only on the parameters [si ] defined by the ... for example, the product for bound states in homoge- neous, power potentials is ... review article in a monograph on statistical complexity3 which summarizes the various ...
Bounding quantum gate error rate based on reported average fidelity
International Nuclear Information System (INIS)
Sanders, Yuval R; Wallman, Joel J; Sanders, Barry C
2016-01-01
Remarkable experimental advances in quantum computing are exemplified by recent announcements of impressive average gate fidelities exceeding 99.9% for single-qubit gates and 99% for two-qubit gates. Although these high numbers engender optimism that fault-tolerant quantum computing is within reach, the connection of average gate fidelity with fault-tolerance requirements is not direct. Here we use reported average gate fidelity to determine an upper bound on the quantum-gate error rate, which is the appropriate metric for assessing progress towards fault-tolerant quantum computation, and we demonstrate that this bound is asymptotically tight for general noise. Although this bound is unlikely to be saturated by experimental noise, we demonstrate using explicit examples that the bound indicates a realistic deviation between the true error rate and the reported average fidelity. We introduce the Pauli distance as a measure of this deviation, and we show that knowledge of the Pauli distance enables tighter estimates of the error rate of quantum gates. (fast track communication)
Spent Nuclear Fuel (SNF) Bounding Drop Support Calculations
Energy Technology Data Exchange (ETDEWEB)
CHENAULT, D.M.
1999-11-16
This report evaluates different drop heights, concrete and other impact media to which the transport package and/or the MCO is dropped. A prediction method is derived for estimating the resultant impact factor for determining the bounding drop case for the SNF Project.
Hartree–Fock variational bounds for ground state energy of ...
Indian Academy of Sciences (India)
We use different determinantal Hartree–Fock (HF) wave functions to calculate true variational upper bounds for the ground state energy of spin-half fermions in volume 0, with mass , electric charge zero, and magnetic moment , interacting through magnetic dipole–dipole interaction. We ﬁnd that at high densities ...
A Finite Continuation Algorithm for Bound Constrained Quadratic Programming
DEFF Research Database (Denmark)
Madsen, Kaj; Nielsen, Hans Bruun; Pinar, Mustafa C.
1999-01-01
The dual of the strictly convex quadratic programming problem with unit bounds is posed as a linear $\\ell_1$ minimization problem with quadratic terms. A smooth approximation to the linear $\\ell_1$ function is used to obtain a parametric family of piecewise-quadratic approximation problems...
Determination of bounds on failure probability in the presence of ...
Indian Academy of Sciences (India)
A fundamental component of safety assessment is the appropriate representation and incorporation of uncertainty. A procedure for handling hybrid uncertainties in stochastic mechanics problems is presented. The procedure can be used for determining the bounds on failure probability for cases where failure probability is a ...
Communication complexity: A treasure house of lower bounds
Indian Academy of Sciences (India)
admin
Communication complexity: A treasure house of lower bounds. Consider the following intriguing problem in the Mughal court: Akbar, known for his political sagacity, and Birbal, skilled in administrative affairs, want to come to a common understanding on matters of state. Being men of few words, they want to achieve this with ...
A criterion on compactness of the set of bounded solutions
International Nuclear Information System (INIS)
Tusen Huang; Qi Zhang
2004-01-01
A necessary and sufficient condition that the set of bounded solutions for the ordinary differential equations ((dx)/(dt))=f(x) defined on R n is compact is given. This result generalizes the corresponding result in [(Conf. Board Math. Sci., No 38) Am. Math. Sci., Providence, 1978, p. 30
Bounds on charged lepton mixing with exotic charged leptons Ф
Indian Academy of Sciences (India)
bounds on mixings in charged lepton sector. The threshold of the process. /. × = 2С is high, and masses of light .... between the two sectors (i.e., ordinary weak states ( 0-. OL(R)) to the heavy mass eigenstates (. hL(R)) and exotic ... Ш3 and Й denote third isospin compo- nent and electrical charge of the corresponding fields.
Analysis of pressure variation of fluid in bounded circular reservoirs ...
African Journals Online (AJOL)
The result obtained at the wellbore was compared with the results obtained by Van Everdigen and Hurst. It was shown that there was a strong positive correlation between the results. Keywords: Bounded circular reservoir, constant terminal rate, dimensionless variables, diffusivity equation, and Crank-Nicholson scheme.
The generalized pseudospectral approach to the bound states of the ...
Indian Academy of Sciences (India)
Abstract. The generalized pseudospectral (GPS) method is employed to calculate the bound states of the Hulthén and the Yukawa potentials in quantum mechanics, with special emphasis on higher excited states and stronger couplings. Accurate energy eigenvalues, expectation values and radial probability densities are ...