Manifolds with integrable affine shape operator
Directory of Open Access Journals (Sweden)
Daniel A. Joaquín
2005-05-01
Full Text Available This work establishes the conditions for the existence of vector fields with the property that theirs covariant derivative, with respect to the affine normal connection, be the affine shape operatorS in hypersurfaces. Some results are obtained from this property and, in particular, for some kind of affine decomposable hypersurfaces we explicitely get the actual vector fields.
Affine transformations capture beak shape variation in Darwin's Finches
Brenner, Michael; Campas, Otger; Mallarino, Riccardo; Abzhanov, Arhat
2009-11-01
Evolution by natural selection has resulted in extraordinary morphological complexity of living organisms, whose description has thus far defied any precise mathematical characterization linked to the underlying developmental genetics. Here we demonstrate that the morphological diversity of the beaks of Darwin's finches, the classical example of adaptive morphological radiation, is quantitatively accounted for through the mathematical group of affine transformations. Specifically, we show that all beak shapes of Ground Finches (genus Geospiza) are related by scaling transformations (a subgroup of the affine group), and the same scheme occurs for all the beak shapes of Tree and Warbler finches. This analysis shows that the beak shapes within each of these groups differ only by their scales, such as length and depth, each of which is knownto be under genetic control.The complete morphological variability within the beaks of Darwin's finches can be explained by extending the scaling transformations to the entire affine group, by including shear transformations. Altogether our results suggest that the mathematical theory of groups can help decode morphological variability, and points to a potentially hierarchical structure of morphological diversity and the underlying developmental processes.
DNA Shape Dominates Sequence Affinity in Nucleosome Formation
Freeman, Gordon S.; Lequieu, Joshua P.; Hinckley, Daniel M.; Whitmer, Jonathan K.; de Pablo, Juan J.
2014-10-01
Nucleosomes provide the basic unit of compaction in eukaryotic genomes, and the mechanisms that dictate their position at specific locations along a DNA sequence are of central importance to genetics. In this Letter, we employ molecular models of DNA and proteins to elucidate various aspects of nucleosome positioning. In particular, we show how DNA's histone affinity is encoded in its sequence-dependent shape, including subtle deviations from the ideal straight B-DNA form and local variations of minor groove width. By relying on high-precision simulations of the free energy of nucleosome complexes, we also demonstrate that, depending on DNA's intrinsic curvature, histone binding can be dominated by bending interactions or electrostatic interactions. More generally, the results presented here explain how sequence, manifested as the shape of the DNA molecule, dominates molecular recognition in the problem of nucleosome positioning.
Exploiting Affine Invariant Regions and Leaf Edge Shapes for Weed Detection
DEFF Research Database (Denmark)
Kazmi, Wajahat; Ruiz, Francisco Garcia; Nielsen, Jon
2015-01-01
. Then a comparison with the field data retrieval highlighted the trade-off due to the field challenges. Adopting a comprehensive approach, edge shape detectors and homogeneous surface detecting affine invariant regions were fused. In order to integrate vegetation indices as local features, a new local vegetation...
Stiller, Peter F.
2004-10-01
Recent progress in shape theory, including the development of object/image equations for shape matching and shape space metrics (especially object/image metrics), is now being exploited to develop new algorithms for target recognition. This theory makes use of advanced mathematical techniques from algebraic and differential geometry to construct generalized shape spaces for various projection and sensor models, and then uses that construction to find natural metrics that express the distance (difference) between two configurations of object features, two configurations of image features, or an object and an image pair. Such metrics produce the most robust tests for target identification; at least as far as target geometry is concerned. Moreover, they also provide the basis for efficient hashing schemes to do target identification quickly and provide a rigorous foundation for error analysis in ATR.
Size and shape dependent deprotonation potential and proton affinity of nanodiamond
Barnard, Amanda S.; Per, Manolo C.
2014-11-01
Many important reactions in biology and medicine involve proton abstraction and transfer, and it is integral to applications such as drug delivery. Unlike electrons, which are quantum mechanically delocalized, protons are instantaneously localized on specific residues in these reactions, which can be a distinct advantage. However, the introduction of nanoparticles, such as non-toxic nanodiamonds, to this field complicates matters, as the number of possible sites increases as the inverse radius of the particle. In this paper we present \\gt {{10}4} simulations that map the size- and shape-dependence of the deprotonation potential and proton affinity of nanodiamonds in the range 1.8-2.7 nm in average diameter. We find that while the average deprotonation potential and proton affinities decrease with size, the site-specific values are inhomogeneous over the surface of the particles, exhibiting strong shape-dependence. The proton affinity is strongly facet-dependent, whereas the deprotonation potential is edge/corner-dependent, which creates a type of spatial hysteresis in the transfer of protons to and from the nanodiamond, and provides new opportunities for selective functionalization.
Relating the shape of protein binding sites to binding affinity profiles: is there an association?
Directory of Open Access Journals (Sweden)
Bitter István
2010-10-01
Full Text Available Abstract Background Various pattern-based methods exist that use in vitro or in silico affinity profiles for classification and functional examination of proteins. Nevertheless, the connection between the protein affinity profiles and the structural characteristics of the binding sites is still unclear. Our aim was to investigate the association between virtual drug screening results (calculated binding free energy values and the geometry of protein binding sites. Molecular Affinity Fingerprints (MAFs were determined for 154 proteins based on their molecular docking energy results for 1,255 FDA-approved drugs. Protein binding site geometries were characterized by 420 PocketPicker descriptors. The basic underlying component structure of MAFs and binding site geometries, respectively, were examined by principal component analysis; association between principal components extracted from these two sets of variables was then investigated by canonical correlation and redundancy analyses. Results PCA analysis of the MAF variables provided 30 factors which explained 71.4% of the total variance of the energy values while 13 factors were obtained from the PocketPicker descriptors which cumulatively explained 94.1% of the total variance. Canonical correlation analysis resulted in 3 statistically significant canonical factor pairs with correlation values of 0.87, 0.84 and 0.77, respectively. Redundancy analysis indicated that PocketPicker descriptor factors explain 6.9% of the variance of the MAF factor set while MAF factors explain 15.9% of the total variance of PocketPicker descriptor factors. Based on the salient structures of the factor pairs, we identified a clear-cut association between the shape and bulkiness of the drug molecules and the protein binding site descriptors. Conclusions This is the first study to investigate complex multivariate associations between affinity profiles and the geometric properties of protein binding sites. We found that
Wang, Yuhuang; Maspoch, Daniel; Zou, Shengli; Schatz, George C.; Smalley, Richard E.; Mirkin, Chad A.
2006-02-01
Directed assembly of nanoscale building blocks such as single-walled carbon nanotubes (SWNTs) into desired architectures is a major hurdle for a broad range of basic research and technological applications (e.g., electronic devices and sensors). Here we demonstrate a parallel assembly process that allows one to simultaneously position, shape, and link SWNTs with sub-100-nm resolution. Our method is based on the observation that SWNTs are strongly attracted to COOH-terminated self-assembled monolayers (COOH-SAMs) and that SWNTs with lengths greater than the dimensions of a COOH-SAM feature will align along the boundary between the COOH-SAM feature and a passivating CH3-terminated SAM. By using nanopatterned affinity templates of 16-mercaptohexadecanonic acid, passivated with 1-octadecanethiol, we have formed SWNT dot, ring, arc, letter, and even more sophisticated structured thin films and continuous ropes. Experiment and theory (Monte Carlo simulations) suggest that the COOH-SAMs localize the solvent carrying the nanotubes on the SAM features, and that van der Waals interactions between the tubes and the COOH-rich feature drive the assembly process. A mathematical relationship describing the geometrically weighted interactions between SWNTs and the two different SAMs required to overcome solvent-SWNT interactions and effect assembly is provided. self-assembly | rings | structured thin films | Monte Carlo simulations
Overall, Nickola C; Hammond, Matthew D; McNulty, James K; Finkel, Eli J
2016-08-01
When does power in intimate relationships shape important interpersonal behaviors, such as psychological aggression? Five studies tested whether possessing low relationship power was associated with aggressive responses, but (a) only within power-relevant relationship interactions when situational power was low, and (b) only by men because masculinity (but not femininity) involves the possession and demonstration of power. In Studies 1 and 2, men lower in relationship power exhibited greater aggressive communication during couples' observed conflict discussions, but only when they experienced low situational power because they were unable to influence their partner. In Study 3, men lower in relationship power reported greater daily aggressive responses toward their partner, but only on days when they experienced low situational power because they were either (a) unable to influence their partner or (b) dependent on their partner for support. In Study 4, men who possessed lower relationship power exhibited greater aggressive responses during couples' support-relevant discussions, but only when they had low situational power because they needed high levels of support. Study 5 provided evidence for the theoretical mechanism underlying men's aggressive responses to low relationship power. Men who possessed lower relationship power felt less manly on days they faced low situational power because their partner was unwilling to change to resolve relationship problems, which in turn predicted greater aggressive behavior toward their partner. These results demonstrate that fully understanding when and why power is associated with interpersonal behavior requires differentiating between relationship and situational power. (PsycINFO Database Record
Affine Equivalence of Quartic Monomial Rotation Symmetric Boolean Functions in Prime Power Dimension
2015-01-27
Odd Number of Variables, International Work- shop on Boolean Functions : Cryptography and Applications (BFCA 2005), University of Rouen, France (2005...Affine Equivalence of Quartic Monomial Rotation Symmetric Boolean Functions in Prime Power Dimension Pantelimon Stănică Naval Postgraduate School... Department of Applied Mathematics, Monterey, CA 93943–5216, USA; pstanica@nps.edu Abstract In this paper we analyze and exactly compute the number of
Lind, Mats; Lee, Young Lim; Mazanowski, Janusz; Kountouriotis, Georgios K; Bingham, Geoffrey P
2014-02-01
G. P. Bingham and M. Lind (2008, Large continuous perspective transformations are necessary and sufficient for accurate perception of metric shape, Perception & Psychophysics, Vol. 70, pp. 524-540) showed that observers could perceive metric shape, given perspective changes ≥ 45° relative to a principal axis of elliptical cylinders. In this article, we tested (a) arbitrary perspective changes of 45°, (b) whether perception gradually improves with more perspective change, (c) speed of rotation, (d) whether this works with other shapes (asymmetric polyhedrons), (e) different slants, and (f) perspective changes >45°. Experiment 1 compared 45° perspective change away from, versus centered on, a principal axis. Observers adjusted an ellipse to match the cross-section of an elliptical cylinder viewed in a stereo-motion display. Experiment 2 tested whether performance would improve gradually with increases in perspective change, or suddenly with a 45° change. We also tested speed of rotation. Experiment 3 tested (a) asymmetric polyhedrons, (b) perspective change beyond 45°, and (c) the effect of slant. The results showed (a) a particular perspective was not required, (b) judgments only improved with ≥ 45° change, (c) speed was not relevant, (d) it worked with asymmetric polyhedrons, (e) slant was not relevant, and (f) judgments remained accurate beyond 45° of change. A model shows how affine operations, together with a symmetry yielded by 45° perspective change, bootstrap perception of metric shape.
Electron beam machining using rotating and shaped beam power distribution
Elmer, John W.; O'Brien, Dennis W.
1996-01-01
An apparatus and method for electron beam (EB) machining (drilling, cutting and welding) that uses conventional EB guns, power supplies, and welding machine technology without the need for fast bias pulsing technology. The invention involves a magnetic lensing (EB optics) system and electronic controls to: 1) concurrently bend, focus, shape, scan, and rotate the beam to protect the EB gun and to create a desired effective power-density distribution, and 2) rotate or scan this shaped beam in a controlled way. The shaped beam power-density distribution can be measured using a tomographic imaging system. For example, the EB apparatus of this invention has the ability to drill holes in metal having a diameter up to 1000 .mu.m (1 mm or larger), compared to the 250 .mu.m diameter of laser drilling.
Wang, Yuhuang; Maspoch, Daniel; Zou, Shengli; Schatz, George C.; Smalley, Richard E.; Mirkin, Chad A.
2006-01-01
Directed assembly of nanoscale building blocks such as single-walled carbon nanotubes (SWNTs) into desired architectures is a major hurdle for a broad range of basic research and technological applications (e.g., electronic devices and sensors). Here we demonstrate a parallel assembly process that allows one to simultaneously position, shape, and link SWNTs with sub-100-nm resolution. Our method is based on the observation that SWNTs are strongly attracted to COOH-terminated self-assembled mo...
Event Shapes and Power Correction Results from HERA
McCance, G J
2000-01-01
Inclusive event shape variables have been measured in the Breit Frame for neutral current deep-inelastic positron-proton scattering using the H1 and ZEUS detectors at HERA. The variables thrust, jet broadening, C-parameter, jet mass and two kinds of differential two-jet rate have been studied in the kinematic range 7 < Q < 100 GeV. The Q dependence of the shape variables have been compared with QCD applying power corrections proportional to 1/Q^p to account for hadronisation effects. The concept of power corrections is tested by fitting the strong coupling constant alpha_s and a non-perturbative parameter alpha(p-1)_bar.
Freeform beam shaping for high-power multimode lasers
Laskin, Alexander; Laskin, Vadim
2014-03-01
Widening of using high power multimode lasers in industrial laser material processing is accompanied by special requirements to irradiance profiles in such technologies like metal or plastics welding, cladding, hardening, brazing, annealing, laser pumping and amplification in MOPA lasers. Typical irradiance distribution of high power multimode lasers: free space solid state, fiber-coupled solid state and diodes lasers, fiber lasers, is similar to Gaussian. Laser technologies can be essentially improved when irradiance distribution on a workpiece is uniform (flattop) or inverse-Gauss; when building high-power pulsed lasers it is possible to enhance efficiency of pumping and amplification by applying super-Gauss irradiance distribution with controlled convexity. Therefore, "freeform" beam shaping of multimode laser beams is an important task. A proved solution is refractive field mapping beam shaper like Shaper capable to control resulting irradiance profile - with the same unit it is possible to get various beam profiles and choose optimum one for a particular application. Operational principle of these devices implies transformation of laser irradiance distribution by conserving beam consistency, high transmittance, providing collimated low divergent output beam. Using additional optics makes it possible to create resulting laser spots of necessary size and round, elliptical or linear shape. Operation out of focal plane and, hence, in field of lower wavefront curvature, allows extending depth of field. The refractive beam shapers are implemented as telescopes and collimating systems, which can be connected directly to fiber-coupled lasers or fiber lasers, thus combining functions of beam collimation and irradiance transformation.
Shape optimization of a thick-walled power boiler component
Directory of Open Access Journals (Sweden)
Duda Piotr
2017-01-01
Full Text Available This paper presents a methodology and successful application of structural optimization of a T-pipe under transient thermal and mechanical loads. In order to find the optimal shape of a thick-walled power boiler component, a parametric FE model and the evolutionary algorithm (EA are applied. The power boiler start-up and shutdown curves are based on the TRD 301 guidelines. Maximum total stresses are assumed as optimization constraints. The obtained geometry is by about 18.6% lighter than the original one due to thinning of the walls. Maximum tensile and compressive stresses in the modified geometry are smaller than in the original one during the whole cycle. Additionally, lower total stress values are recorded during heating and cooling processes. Therefore, these transient processes can be accelerated and the shutdown and start-up losses can be reduced.
Shape Biased Low Power Spin Dependent Tunneling Magnetic Field Sensors
Tondra, Mark; Qian, Zhenghong; Wang, Dexin; Nordman, Cathy; Anderson, John
2001-10-01
Spin Dependent Tunneling (SDT) devices are leading candidates for inclusion in a number of Unattended Ground Sensor applications. Continued progress at NVE has pushed their performance to 1OOs of pT I rt. Hz 1 Hz. However, these sensors were designed to use an applied field from an on-chip coil to create an appropriate magnetic sensing configuration. The power required to generate this field (^100mW) is significantly greater than the power budget (^lmW) for a magnetic sensor in an Unattended Ground Sensor (UGS) application. Consequently, a new approach to creating an ideal sensing environment is required. One approach being used at NVE is "shape biasing." This means that the physical layout of the SDT sensing elements is such that the magnetization of the sensing film is correct even when no biasing field is applied. Sensors have been fabricated using this technique and show reasonable promise for UGS applications. Some performance trade-offs exist. The power is easily tinder 1 MW, but the sensitivity is typically lower by a factor of 10. This talk will discuss some of the design details of these sensors as well as their expected ultimate performance.
Shape changing thin films powered by DNA hybridization
Shim, Tae Soup; Estephan, Zaki G.; Qian, Zhaoxia; Prosser, Jacob H.; Lee, Su Yeon; Chenoweth, David M.; Lee, Daeyeon; Park, So-Jung; Crocker, John C.
2017-01-01
Active materials that respond to physical and chemical stimuli can be used to build dynamic micromachines that lie at the interface between biological systems and engineered devices. In principle, the specific hybridization of DNA can be used to form a library of independent, chemically driven actuators for use in such microrobotic applications and could lead to device capabilities that are not possible with polymer- or metal-layer-based approaches. Here, we report shape changing films that are powered by DNA strand exchange reactions with two different domains that can respond to distinct chemical signals. The films are formed from DNA-grafted gold nanoparticles using a layer-by-layer deposition process. Films consisting of an active and a passive layer show rapid, reversible curling in response to stimulus DNA strands added to solution. Films consisting of two independently addressable active layers display a complex suite of repeatable transformations, involving eight mechanochemical states and incorporating self-righting behaviour.
仿射变换对二维蕨类形状控制的研究%Affine Transformation for Two-dimensional Fern Shape Control
Institute of Scientific and Technical Information of China (English)
包晔
2012-01-01
通过对仿射变换矩阵系数进行调节分析，研究仿射变换矩阵对二维蕨类形状控制的作用，并分析仿射变换矩阵的各个系数对二维蕨类植物生成的形状和弯曲方向的影响，给出了蕨类植物形状控制方法，证明能较好地控制蕨类植物叶片的生长方向和形状，但还不能够控制叶片生成的精确角度和叶片的精确大小．%In this paper, affine transformation matrix of two-dimensional fern shape control is analyzed, and the affine trans- formation matrix coefficients on the shape generated by the two-dimensional ferns are adjusted and the bending directions are given. Better controlling approaches to the direction and shape of fern leaves are put forward in detail.
Han, Wenhua; Shen, Xiaohui; Xu, Jun; Wang, Ping; Tian, Guiyun; Wu, Zhengyang
2014-09-04
Magnetic flux leakage (MFL) inspection is one of the most important and sensitive nondestructive testing approaches. For online MFL inspection of a long-range railway track or oil pipeline, a fast and effective defect profile estimating method based on a multi-power affine projection algorithm (MAPA) is proposed, where the depth of a sampling point is related with not only the MFL signals before it, but also the ones after it, and all of the sampling points related to one point appear as serials or multi-power. Defect profile estimation has two steps: regulating a weight vector in an MAPA filter and estimating a defect profile with the MAPA filter. Both simulation and experimental data are used to test the performance of the proposed method. The results demonstrate that the proposed method exhibits high speed while maintaining the estimated profiles clearly close to the desired ones in a noisy environment, thereby meeting the demand of accurate online inspection.
The Power of Strong Fourier Sampling: Quantum Algorithms for Affine Groups and Hidden Shifts
Moore, Cristopher; Russell, A; Schulman, L J; Moore, Cristopher; Rockmore, Daniel; Russell, Alexander; Schulman, Leonard J.
2005-01-01
Many quantum algorithms, including Shor's celebrated factoring and discrete log algorithms, proceed by reduction to a Hidden Subgroup problem, in which an unknown subgroup H of a group G must be determined from a uniform superposition on a left coset of H. These hidden subgroup problems are typically solved by Fourier sampling. When G is nonabelian, two important variants of Fourier sampling have been identified: the weak standard method, where only representation names are measured, and the strong standard method, where full measurement (i.e., the row and column of the representation, in a suitably chosen basis) occurs. It has remained open whether the strong standard method is indeed stronger. In this article, we settle this question in the affirmative. We show that hidden subgroups H of the q-hedral groups, i.e., semidirect products Z_q \\ltimes Z_p where q | (p-1), and in particular the affine groups A_p, can be information-theoretically reconstructed using the strong standard method. Moreover, if |H| = p/...
A low frequency piezoelectric power harvester using a spiral-shaped bimorph
Institute of Scientific and Technical Information of China (English)
HU Yuantai; HU Hongping; YANG Jiashi
2006-01-01
We propose a spiral-shaped piezoelectric bimorph power harvester operating with coupled flexural and extensional vibration modes for applications to low frequency energy sources.A theoretical analysis is performed and the computational results show that the spiral structure has relatively low operating frequency compared to beam power harvesters of the same size.It is found that to optimize the performance of a piezoelectric spiral-shaped harvester careful design is needed.
Commitment and dispatch of heat and power units via affinely adjustable robust optimization
DEFF Research Database (Denmark)
Zugno, Marco; Morales González, Juan Miguel; Madsen, Henrik
2016-01-01
The joint management of heat and power systems is believed to be key to the integration of renewables into energy systems with a large penetration of district heating. Determining the day-ahead unit commitment and production schedules for these systems is an optimization problem subject...... to uncertainty stemming from the unpredictability of demand and prices for heat and electricity. Furthermore, owing to the dynamic features of production and heat storage units as well as to the length and granularity of the optimization horizon (e.g., one whole day with hourly resolution), this problem...... approach. Secondly, we appraise the gain obtained by switching from linear to piecewise-linear decision rules within robust optimization. Furthermore, we give directions for selecting the parameters defining the uncertainty set (size, budget) and assess the resulting trade-off between average profit...
Affine and degenerate affine BMW algebras: Actions on tensor space
Daugherty, Zajj; Virk, Rahbar
2012-01-01
The affine and degenerate affine Birman-Murakami-Wenzl (BMW) algebras arise naturally in the context of Schur-Weyl duality for orthogonal and symplectic quantum groups and Lie algebras, respectively. Cyclotomic BMW algebras, affine and cyclotomic Hecke algebras, and their degenerate versions are quotients. In this paper we explain how the affine and degenerate affine BMW algebras are tantalizers (tensor power centralizer algebras) by defining actions of the affine braid group and the degenerate affine braid algebra on tensor space and showing that, in important cases, these actions induce actions of the affine and degenerate affine BMW algebras. We then exploit the connection to quantum groups and Lie algebras to determine universal parameters for the affine and degenerate affine BMW algebras. Finally, we show that the universal parameters are central elements--the higher Casimir elements for orthogonal and symplectic enveloping algebras and quantum groups.
DEFF Research Database (Denmark)
Tafuri, Felice Francesco; Sira, Daniel; Jensen, Ole Kiel
2013-01-01
of the input envelope by means of two shaping functions jointly designed on the basis of a single-tone characterization. The presented technique is demonstrated by means of measurements on a commercial GaAs HBT power amplifier. Measured results showed a PA power added efficiency (PAE) of 51.9%, an error vector...
Design of measurement equipment for high power laser beam shapes
DEFF Research Database (Denmark)
Hansen, K. S.; Olsen, F. O.; Kristiansen, Morten;
2013-01-01
To analyse advanced high power beam patterns, a method, which is capable of analysing the intensity distribution in 3D is needed. Further a measuring of scattered light in the same system is preferred. This requires a high signal to noise ratio. Such a system can be realised by a CCD......-chip implemented in a camera system. Most available CCD-based systems do however suffer from a low maximum intensity threshold. Therefore attenuation is needed. This paper describes the construction of such a beam analysing system where beam patterns produced by single mode fiber laser on a diffractic optical...... element can be evaluated using a CCD based camera. The system is tested with various DOE’s for evaluation of efficiency and measurement of scattered light with success. Also tests with capturing beam caustics of focused laser beams from which beam parameters has been fitted and compared with measurements...
Beam shaping design for coupling high power diode laser stack to fiber.
Ghasemi, Seyed Hamed; Hantehzadeh, Mohammad-Reza; Sabbaghzadeh, Jamshid; Dorranian, Davoud; Lafooti, Majid; Vatani, Vahid; Rezaei-Nasirabad, Reza; Hemmati, Atefeh; Amidian, Ali Asghar; Alavian, Seyed Ali
2011-06-20
A beam shaping technique that rearranges the beam for improving the beam symmetry and power density of a ten-bar high power diode laser stack is simulated considering a stripe mirror plate and a V-Stack mirror in the beam shaping system. In this technique, the beam of a high power diode laser stack is effectively coupled into a standard 550 μm core diameter and a NA=0.22 fiber. By this technique, compactness, higher efficiency, and lower cost production of the diode are possible.
Beam shaping to provide round and square-shaped beams in optical systems of high-power lasers
Laskin, Alexander; Laskin, Vadim
2016-05-01
Optical systems of modern high-power lasers require control of irradiance distribution: round or square-shaped flat-top or super-Gaussian irradiance profiles are optimum for amplification in MOPA lasers and for thermal load management while pumping of crystals of solid-state ultra-short pulse lasers to control heat and minimize its impact on the laser power and beam quality while maximizing overall laser efficiency, variable profiles are also important in irradiating of photocathode of Free Electron lasers (FEL). It is suggested to solve the task of irradiance re-distribution using field mapping refractive beam shapers like piShaper. The operational principle of these devices presumes transformation of laser beam intensity from Gaussian to flat-top one with high flatness of output wavefront, saving of beam consistency, providing collimated output beam of low divergence, high transmittance, extended depth of field, negligible residual wave aberration, and achromatic design provides capability to work with ultra-short pulse lasers having broad spectrum. Using the same piShaper device it is possible to realize beams with flat-top, inverse Gauss or super Gauss irradiance distribution by simple variation of input beam diameter, and the beam shape can be round or square with soft edges. This paper will describe some design basics of refractive beam shapers of the field mapping type and optical layouts of their applying in optical systems of high-power lasers. Examples of real implementations and experimental results will be presented as well.
Kaur, Sarabjeet; Graak, Pinki; Gupta, Ankita; Chhabra, Priya; Kumar, Dinesh; Shetty, Arjun
2016-04-01
Piezoelectric energy harvesting systems are used to convert vicinity vibrations into useful electrical energy. Effect of various shapes and materials open the gateway towards the choice of maximum power generation for the micro and nano world. Comsol Multiphysics was used to simulate the four designed shapes named as Pi, E, Rectangular and T in the size range of less than 1mm but greater than 1 micron. Designed shapes worked under the impact of ambient vibrations using few piezoelectric materials for the maximum power generation so that traditional power sources can be replaced with such piezoelectric energy harvester. A layer of piezoelectric material (PZT-5H, AlN, BaTiO3) of thickness 0.5 µm is added to the cantilever and the base material is silicon of thickness 1.5 µm. Simulations were performed using the piezoelectric device module of Comsol Multiphysics. All three materials were studied for the all four cantilever geometries. The generated power was observed maximum as 382.5 µW in case of the barium titanate material with rectangular shape geometry but the displacement is 0.132 µm which is very less whereas E shape cantilever shows the maximum displacement of 0.6078 µm in case of PZT-5H, Hence rectangular shape with barium titanate material is concluded to be good for maximum power generation but the displacement factor cannot be neglected, hence the cantilever with E shape geometry is considered as the best with a generated power of 49.005 µW and a displacement of 0.6078 µm.
U-shape magnetostrictive vibration based power generator for universal use
Ueno, T.
2016-04-01
Vibrational power generator extracts electrical energy from ambient vibration. Author invented novel configuration using magnetostrictive material. The device is based on parallel beams of iron-gallium alloy and magnetic material, and features high efficiency, high robustness, and low electrical impedance. In this paper, author proposes U-shape generator for universal use. It consists of the parallel beams and fixed and free end beams forming U-shape frame flexibly modified for variety of mechanical input. Miniature U-shape prototype using Fe-Ga rod 6 by 0.5 by 13 mm3 exhibited average power of 3.7 mW under vibration of 166 Hz and 2.5 G. L-shape type was demonstrated to generate electromotive force by two directional vibrations. In switch type, maximum energy of 0.7 mJ was retrieved by one pushing force. The performances are sufficient to drive wireless module for heath monitoring and remote control.
Research on vibration characteristics of L-shaped plate using a mobility power flow approach
Institute of Scientific and Technical Information of China (English)
CHEN Xiao-li; SHENG Mei-ping
2007-01-01
L-shaped plates have become an important focuses in structural vibration research. To determine their vibration characteristics, this paper applied a mobility power flow method. Firstly, the L-shaped plate was divided into two substructures to simplify analysis. The coupled bending moment was then deduced by applying a continuous vibration property on the common edge. Next, the response on any point of the plate and the input and transmitted power flow formulas were calculated. Numerical simulations showed the distribution of the coupled bending moment and the response of the whole structure. The validity of this method was verified by the SEA approach.
Efficient pump beam shaping for high-power thin-disk laser systems.
Pereira, Rui; Weichelt, Birgit; Liang, Dawei; Morais, Paulo J; Gouveia, Helena; Abdou-Ahmed, Marwan; Voss, Andreas; Graf, Thomas
2010-09-20
We report a beam-shaping technique whereby the output power from a high-power laser-diode stack is efficiently coupled, reconfigured, and transmitted to a thin-disk laser by means of a compact optical fiber bundle. By using this technique, the power density is increased by a factor of 2 when compared to direct coupling with a octagonal fused silica rod while the numerical aperture is kept constant. Transmission efficiency of 80% was measured for the beam shaper without antireflection coating. The top-hat distribution is numerically calculated at the thin-disk laser crystal.
All-in-One Shape-Adaptive Self-Charging Power Package for Wearable Electronics.
Guo, Hengyu; Yeh, Min-Hsin; Lai, Ying-Chih; Zi, Yunlong; Wu, Changsheng; Wen, Zhen; Hu, Chenguo; Wang, Zhong Lin
2016-11-22
Recently, a self-charging power unit consisting of an energy harvesting device and an energy storage device set the foundation for building a self-powered wearable system. However, the flexibility of the power unit working under extremely complex deformations (e.g., stretching, twisting, and bending) becomes a key issue. Here, we present a prototype of an all-in-one shape-adaptive self-charging power unit that can be used for scavenging random body motion energy under complex mechanical deformations and then directly storing it in a supercapacitor unit to build up a self-powered system for wearable electronics. A kirigami paper based supercapacitor (KP-SC) was designed to work as the flexible energy storage device (stretchability up to 215%). An ultrastretchable and shape-adaptive silicone rubber triboelectric nanogenerator (SR-TENG) was utilized as the flexible energy harvesting device. By combining them with a rectifier, a stretchable, twistable, and bendable, self-charging power package was achieved for sustainably driving wearable electronics. This work provides a potential platform for the flexible self-powered systems.
Device for measurement of power and shape of radio frequency pulses in nuclear magnetic resonance
Pfeffer, M.; Řezníček, R.; Křišťan, P.; Štěpánková, H.
2012-05-01
A design of an instrument to measure the power and shape of radio frequency (RF) pulses operating in a broad frequency range is described. The device is capable of measuring the pulse power up to 500 W of both CW and extremely short (˜1 μs) RF pulses of arbitrary period. The pulse envelope can be observed on a logarithmic scale on a corresponding instrument output using an inexpensive storage oscilloscope. The instrument consists of a coaxial measurement head, the RF processing circuits and an AD conversion and display unit. The whole device is based on widely available integrated circuits; thus, good reproducibility and adaptability of the design is ensured. Since the construction is intended to be used in particular (but not solely) in nuclear magnetic resonance spectroscopy, we found it useful to provide a demonstration of two typical usage scenarios. Other application fields may comprise magnetic resonance imaging, radar and laser technology, power amplifier testing, etc.
Mitigation of Power frequency Magnetic Fields. Using Scale Invariant and Shape Optimization Methods
Energy Technology Data Exchange (ETDEWEB)
Salinas, Ener; Yueqiang Liu; Daalder, Jaap; Cruz, Pedro; Antunez de Souza, Paulo Roberto Jr; Atalaya, Juan Carlos; Paula Marciano, Fabianna de; Eskinasy, Alexandre
2006-10-15
The present report describes the development and application of two novel methods for implementing mitigation techniques of magnetic fields at power frequencies. The first method makes use of scaling rules for electromagnetic quantities, while the second one applies a 2D shape optimization algorithm based on gradient methods. Before this project, the first method had already been successfully applied (by some of the authors of this report) to electromagnetic designs involving pure conductive Material (e.g. copper, aluminium) which implied a linear formulation. Here we went beyond this approach and tried to develop a formulation involving ferromagnetic (i.e. non-linear) Materials. Surprisingly, we obtained good equivalent replacement for test-transformers by varying the input current. In spite of the validity of this equivalence constrained to regions not too close to the source, the results can still be considered useful, as most field mitigation techniques are precisely developed for reducing the magnetic field in regions relatively far from the sources. The shape optimization method was applied in this project to calculate the optimal geometry of a pure conductive plate to mitigate the magnetic field originated from underground cables. The objective function was a weighted combination of magnetic energy at the region of interest and dissipated heat at the shielding Material. To our surprise, shapes of complex structure, difficult to interpret (and probably even harder to anticipate) were the results of the applied process. However, the practical implementation (using some approximation of these shapes) gave excellent experimental mitigation factors.
Assessment of the TMI-2 axial power-shaping-rod dynamic test results
Energy Technology Data Exchange (ETDEWEB)
Garner, R W; Owen, D E; Martin, M R
1983-04-01
The Three Mile Island-Unit 2 (TMI-2) nuclear power reactor contains 61 control rod assemblies and 8 axial power shaping rod assemblies (APSRs). All control rod and APSR drive leadscrews must be uncoupled and removed prior to vessel head removal. Leadscrew removal is facilitated by having the rod assemblies inserted to a down hard-stop position. Following the TMI-2 accident, the eight axial power shaping rods were in a partially withdrawn position (approx. 25% of their full travel). Therefore, a test was performed to attempt to insert the APSRs to the fully inserted, or at least a hard-stop position. In addition, accelerometers were mounted on the drive mechanisms of all the APSRs in an attempt to obtain acoustical signals that would provide some information about the physical condition of the APSRs and of the damaged TMI-2 reactor core. This report describes the TMI-2 APSR Insertion Test performance and results, and presents an evaluation of correlations between APSR insertion information and other available information on the condition of the TMI-2 reactor.
Yuan, Mingquan; Alocilja, Evangelyn C; Chakrabartty, Shantanu
2016-08-01
This paper presents a wireless, self-powered, affinity-based biosensor based on the integration of paper-based microfluidics with our previously reported method for self-assembling radio-frequency (RF) antennas. At the core of the proposed approach is a silver-enhancement technique that grows portions of a RF antenna in regions where target antigens hybridize with target specific affinity probes. The hybridization regions are defined by a network of nitrocellulose based microfluidic channels which implement a self-powered approach to sample the reagent and control its flow and mixing. The integration substrate for the biosensor has been constructed using polyethylene and the patterning of the antenna on the substrate has been achieved using a low-cost ink-jet printing technique. The substrate has been integrated with passive radio-frequency identification (RFID) tags to demonstrate that the resulting sensor-tag can be used for continuous monitoring in a food supply-chain where direct measurement of analytes is typically considered to be impractical. We validate the proof-of-concept operation of the proposed sensor-tag using IgG as a model analyte and using a 915 MHz Ultra-high-frequency (UHF) RFID tagging technology.
Beam shaping in high-power broad-area quantum cascade lasers using optical feedback
Ferré, Simon; Jumpertz, Louise; Carras, Mathieu; Ferreira, Robson; Grillot, Frédéric
2017-01-01
Broad-area quantum cascade lasers with high output powers are highly desirable sources for various applications including infrared countermeasures. However, such structures suffer from strongly deteriorated beam quality due to multimode behavior, diffraction of light and self-focusing. Quantum cascade lasers presenting high performances in terms of power and heat-load dissipation are reported and their response to a nonlinear control based on optical feedback is studied. Applying optical feedback enables to efficiently tailor its near-field beam profile. The different cavity modes are sequentially excited by shifting the feedback mirror angle. Further control of the near-field profile is demonstrated using spatial filtering. The impact of an inhomogeneous gain as well as the influence of the cavity width are investigated. Compared to existing technologies, that are complex and costly, beam shaping with optical feedback is a more flexible solution to obtain high-quality mid-infrared sources. PMID:28287175
Beam shaping in high-power broad-area quantum cascade lasers using optical feedback
Ferré, Simon; Jumpertz, Louise; Carras, Mathieu; Ferreira, Robson; Grillot, Frédéric
2017-03-01
Broad-area quantum cascade lasers with high output powers are highly desirable sources for various applications including infrared countermeasures. However, such structures suffer from strongly deteriorated beam quality due to multimode behavior, diffraction of light and self-focusing. Quantum cascade lasers presenting high performances in terms of power and heat-load dissipation are reported and their response to a nonlinear control based on optical feedback is studied. Applying optical feedback enables to efficiently tailor its near-field beam profile. The different cavity modes are sequentially excited by shifting the feedback mirror angle. Further control of the near-field profile is demonstrated using spatial filtering. The impact of an inhomogeneous gain as well as the influence of the cavity width are investigated. Compared to existing technologies, that are complex and costly, beam shaping with optical feedback is a more flexible solution to obtain high-quality mid-infrared sources.
Lee, Tiane L; Fiske, Susan T; Glick, Peter; Chen, Zhixia
2010-04-01
Gender-based structural power and heterosexual dependency produce ambivalent gender ideologies, with hostility and benevolence separately shaping close-relationship ideals. The relative importance of romanticized benevolent versus more overtly power-based hostile sexism, however, may be culturally dependent. Testing this, northeast US (N=311) and central Chinese (N=290) undergraduates rated prescriptions and proscriptions (ideals) for partners and completed Ambivalent Sexism and Ambivalence toward Men Inventories (ideologies). Multiple regressions analyses conducted on group-specific relationship ideals revealed that benevolent ideologies predicted partner ideals, in both countries, especially for US culture's romance-oriented relationships. Hostile attitudes predicted men's ideals, both American and Chinese, suggesting both societies' dominant-partner advantage.
Improving the power efficiency of SOA-based UWB over fiber systems via pulse shape randomization
Taki, H.; Azou, S.; Hamie, A.; Al Housseini, A.; Alaeddine, A.; Sharaiha, A.
2016-09-01
A simple pulse shape randomization scheme is considered in this paper for improving the performance of ultra wide band (UWB) communication systems using On Off Keying (OOK) or pulse position modulation (PPM) formats. The advantage of the proposed scheme, which can be either employed for impulse radio (IR) or for carrier-based systems, is first theoretically studied based on closed-form derivations of power spectral densities. Then, we investigate an application to an IR-UWB over optical fiber system, by utilizing the 4th and 5th orders of Gaussian derivatives. Our approach proves to be effective for 1 Gbps-PPM and 2 Gbps-OOK transmissions, with an advantage in terms of power efficiency for short distances. We also examine the performance for a system employing an in-line Semiconductor Optical Amplifier (SOA) with the view to achieve a reach extension, while limiting the cost and system complexity.
Energy Technology Data Exchange (ETDEWEB)
He, Bin; Zhang, Xiubin; Zhao, Xingyong [Department of Electrical Engineering, Shanghai Jiaotong University, Shanghai 200240 (China)
2007-12-15
In this paper, the transient stability of multimachine power systems based on structure preserving model (SPM) is considered. The interconnection and damping assignment passivity-based control (IDA-PBC) methodology is extended to solve the excitation regulation problem of SPM represented by a set of differential-algebraic equations. By shaping the total energy function via the introduction of a virtual coupling between the electrical and the mechanical dynamics of the power system, a decentralized excitation control law is proposed to ensure the asymptotic stability of the closed-loop system. The controller is proved to be effective in damping the oscillations and enhancing the system stability by the results of simulation research. (author)
A NEW 3D DESIGN METHOD FOR FOOTWEAR SOLES USING DELCAM PowerSHAPE-e SYSTEM
Directory of Open Access Journals (Sweden)
IONESCU Cozmin
2016-05-01
Full Text Available Design methods of soles and soles injection moulds must be accurate, timely and at the same time, accessible to a wide category of soles and injection moulds designers and manufacturers. For designing soles and injection moulds for soles, various dedicated CAD/CAM systems have been developed, such as: Delcam Shoe Solution (3D, Delcam PowerSHAPE-e (2D and 3D, Padsy II (2D and Padsy III (3D, Shoemaster System (2D and 3D, Lectra System (2D and 3D, Parmel System (2D and ATOS II System (3D. These systems are equipped with colour displays, plotters, digitizers, terminals and other equipment dedicated for computer aided design activities. Designing 3D soles models using computer systems enables the prevention of ambiguities inherited from 2D drawings, thus reducing errors and remanufacturing. Depending on the design complexity of soles, the technical means available for copying shoe soles and the technologies at the disposal of the soles manufacturers, soles and injection moulds designers adopt various design methods. Not all CAD/CAM systems are accessible for all users, because often their purchasing costs are high. Design method developed and presented in this paper, uses Delcam PowerSHAPE software program, which has the advantage that it can be accessed free of charge from the manufacturer's website. At the same time, this software program provides the user with all the necessary tools and instruments needed to design the most complex injection moulds and footwear sole.
OPTIMIZING THE SHAPE OF ROTOR BLADES FOR MAXIMUM POWER EXTRACTION IN MARINE CURRENT TURBINES
Directory of Open Access Journals (Sweden)
J.A. Esfahani
2012-12-01
Full Text Available In this paper the shape of rotor blades in Marine Current Turbines (MCTs are investigated. The evaluation of hydrodynamic loads on blades is performed based on the Blade Element Momentum (BEM theory. The shape of blades is optimized according to the main parameters in the configuration and operation of these devices. The optimization is conducted based on the ability of the blades to harness the maximum energy during operating. The main parameters investigated are the tip speed ratio and angle of attack. Furthermore, the influence of these parameters on the maximum energy extraction from fluid flow over a hydrofoil is evaluated. It is shown that the effect of the angle of attack on power extraction is greater than that of the tip speed ratio, while both are found to be significant. Additionally, the proper angle of attack is the angle at which the lift to drag ratio is at its maximum value. However, if a proper angle of attack is chosen, the variations in power coefficient would not be effectively changed with small variations in the tip speed ratio.
From endurance to power athletes: The changing shape of successful male professional tennis players.
Gale-Watts, Adam S; Nevill, Alan M
2016-11-01
The aim of the present study was to identify whether the relative shape and size characteristics of elite male tennis players have changed over time, and in addition whether any anthropometric parameters characterise the more successful players in Grand Slam tournaments. The height and body mass of the players qualifying for the first round in all four Grand Slam tennis tournaments during the period 1982-2011 was obtained, and successful players defined arbitrarily as those reaching round 3 or beyond. Body mass index (BMI) and the reciprocal ponderal index (RPI) were used as our measures of body shape. Multilevel modelling was used to explore the trend over time using non-linear polynomials. The results suggest that the body shape of elite tennis players has changed over time, with a non-linear (cubic polynomial regression model) increase in BMI and a similar non-linear decline in the RPI. BMI, reflecting greater muscle mass rather than greater adiposity, has emerged as an important factor associated with success, identified by a significantly positive (steeper) "successful player"-by-"year" interaction term. The evidence that the RPI of elite tennis players has also decreased over time, together with a significantly negative "successful player"-by-"year" interaction term, suggests that a more linear (ectomorphic) body shape is a less important factor in terms of success. These results suggest that elite male tennis players are becoming more power trained athletes as opposed to endurance athletes, with greater muscle mass being an important factor associated with success in all Grand Slam tournaments.
Fast planar shape recognition using cascaded affine invariant function%采用级联仿射不变函数的快速平面形状识别
Institute of Scientific and Technical Information of China (English)
史思琦; 石光明; 陈旭阳; 齐飞
2012-01-01
现有的基于小波变换的形状识别算法具有很高的计算复杂度,难以满足许多实时应用的要求.文中提出了基于级联仿射不变函数的快速形状识别算法,用于识别仿射变换下的含噪目标.利用目标轮廓的小波变换可以得到一组仿射不变函数,并进一步构造出级联仿射不变函数.为了保证级联仿射不变函数的平移不变性,预先对轮廓的起始点进行了有效配准.从而通过级联仿射不变函数的内积,方便地度量出目标形状的相似度.与现有基于小波的识别算法相比,所提出的算法具有很低的计算复杂度,其所需CPU时间仅为其它算法的1/7.实验结果验证了该算法的有效性和起始点配准的准确性.%Existing shape recognition methods based on wavelet transform are of high computational cost,so they are not suitable for some real-time applications.A cascaded affine invariant function(CAIF)-based fast recognition algorithm was proposed to recognize the noisy shape under affine transform.The CAIF was constructed by combining a set of affine invariant functions,which were derived by the wavelet coefficients of the shape contour.To ensure the shift invariance of CAIF,the starting point of shape contour was pre-aligned effectively.In this way,the shape similarity could be measured conveniently by the inner product of CAIFs.The proposed algorithm was of low computational complexity and spent only one seventh of the CPU time consumed by other wavelet-based recognition algorithms.Experimental results verify the alignment accuracy and the efficiency of the proposed algorithm.
Doubrawa, P.; Barthelmie, R. J.; Wang, H.; Churchfield, M. J.
2016-09-01
The contribution of wake meandering and shape asymmetry to load and power estimates is quantified by comparing aeroelastic simulations initialized with different inflow conditions: an axisymmetric base wake, an unsteady stochastic shape wake, and a large-eddy simulation with rotating actuator-line turbine representation. Time series of blade-root and tower base bending moments are analyzed. We find that meandering has a large contribution to the fluctuation of the loads. Moreover, considering the wake edge intermittence via the stochastic shape model improves the simulation of load and power fluctuations and of the fatigue damage equivalent loads. These results indicate that the stochastic shape wake simulator is a valuable addition to simplified wake models when seeking to obtain higher-fidelity computationally inexpensive predictions of loads and power.
Beam-shaping technique for improving the beam quality of a high-power laser-diode stack.
Gao, Xin; Ohashi, Hiroyuki; Okamoto, Hiroshi; Takasaka, Masaomi; Shinoda, Kazunori
2006-06-01
We report a beam-shaping technique that reconfigures the beams to improve the beam quality and enhance the power density for a ten-array high-power laser-diode stack by using two optical rectangular cubes and two stripe-mirror plates. The reshaped beam has threefold improvement in beam quality, and its power density is effectively enhanced. On the basis of this technique, we focus the beam of the high-power laser-diode stack to effectively end pump a high-power fiber laser.
Goldberg, Kenneth A; Yashchuk, Valeriy V
2016-05-01
For glancing-incidence optical systems, such as short-wavelength optics used for nano-focusing, incorporating physical factors in the calculations used for shape optimization can improve performance. Wavefront metrology, including the measurement of a mirror's shape or slope, is routinely used as input for mirror figure optimization on mirrors that can be bent, actuated, positioned, or aligned. Modeling shows that when the incident power distribution, distance from focus, angle of incidence, and the spatially varying reflectivity are included in the optimization, higher Strehl ratios can be achieved. Following the works of Maréchal and Mahajan, optimization of the Strehl ratio (for peak intensity with a coherently illuminated system) occurs when the expectation value of the phase error's variance is minimized. We describe an optimization procedure based on regression analysis that incorporates these physical parameters. This approach is suitable for coherently illuminated systems of nearly diffraction-limited quality. Mathematically, this work is an enhancement of the methods commonly applied for ex situ alignment based on uniform weighting of all points on the surface (or a sub-region of the surface). It follows a similar approach to the optimization of apodized and non-uniformly illuminated optical systems. Significantly, it reaches a different conclusion than a more recent approach based on minimization of focal plane ray errors.
Laser ablation of borosilicate glass with high power shaped UV nanosecond laser pulses
von Witzendorff, Philipp; Bordin, Andrea; Suttmann, Oliver; Patel, Rajesh S.; Bovatsek, James; Overmeyer, Ludger
2016-03-01
The application of thin borosilicate glass as interposer material requires methods for separation and drilling of this material. Laser processing with short and ultra-short laser pulses have proven to enable high quality cuts by either direct ablation or internal glass modification and cleavage. A recently developed high power UV nanosecond laser source allows for pulse shaping of individual laser pulses. Thus, the pulse duration, pulse bursts and the repetition rate can be set individually at a maximum output power of up to 60 W. This opens a completely new process window, which could not be entered with conventional Q-switched pulsed laser sources. In this study, the novel pulsed UV laser system was used to study the laser ablation process on 400 μm thin borosilicate glass at different pulse durations ranging from 2 - 10 ns and a pulse burst with two 10 ns laser pulses with a separation of 10 ns. Single line scan experiments were performed to correlate the process parameters and the laser pulse shape with the ablation depth and cutting edge chipping. Increasing the pulse duration within the single pulse experiments from 2 ns to longer pulse durations led to a moderate increase in ablation depth and a significant increase in chipping. The highest material removal was achieved with the 2x10 ns pulse burst. Experimental data also suggest that chipping could be reduced, while maintaining a high ablation depth by selecting an adequate pulse overlap. We also demonstrate that real-time combination of different pulse patterns during drilling a thin borosilicate glass produced holes with low overall chipping at a high throughput rate.
Sensitivity studies for 3-D rod ejection analyses on axial power shape
Energy Technology Data Exchange (ETDEWEB)
Park, Min-Ho; Park, Jin-Woo; Park, Guen-Tae; Ryu, Seok-Hee; Um, Kil-Sup; Lee, Jae-Il [KEPCO NF, Daejeon (Korea, Republic of)
2015-10-15
The current safety analysis methodology using the point kinetics model combined with numerous conservative assumptions result in unrealistic prediction of the transient behavior wasting huge margin for safety analyses while the safety regulation criteria for the reactivity initiated accident are going strict. To deal with this, KNF is developing a 3-D rod ejection analysis methodology using the multi-dimensional code coupling system CHASER. The CHASER system couples three-dimensional core neutron kinetics code ASTRA, sub-channel analysis code THALES, and fuel performance analysis code FROST using message passing interface (MPI). A sensitivity study for 3-D rod ejection analysis on axial power shape (APS) is carried out to survey the tendency of safety parameters by power distributions and to build up a realistic safety analysis methodology while maintaining conservatism. The currently developing 3-D rod ejection analysis methodology using the multi-dimensional core transient analysis code system, CHASER was shown to reasonably reflect the conservative assumptions by tuning up kinetic parameters.
Statistical characteristics of the observed Ly-α forest and the shape of initial power spectrum
Demiański, M.; Doroshkevich, A. G.; Turchaninov, V.
2003-04-01
Properties of approximately 4500 observed Ly α absorbers are investigated using the model of formation and evolution of dark matter (DM) structure elements based on the modified Zel'dovich theory. This model is generally consistent with simulations of absorber formation, describes the large-scale structure (LSS) observed in the galaxy distribution at small redshifts reasonably well and emphasizes the generic similarity of the LSS and absorbers. The simple physical model of absorbers asserts that they are composed of DM and gaseous matter. It allows us to estimate the column density and overdensity of DM and gaseous components and the entropy of the gas trapped within the DM potential wells. The parameters of the DM component are found to be consistent with theoretical expectations for the Gaussian initial perturbations with the warm dark matter-like power spectrum. The basic physical factors responsible for the evolution of the absorbers are discussed. The analysis of redshift distribution of absorbers confirms the self-consistency of the adopted physical model, Gaussianity of the initial perturbations and allows one to estimate the shape of the initial power spectrum at small scales that, in turn, restricts the mass of the dominant fraction of DM particles to MDM>= 1.5-5 keV. Our results indicate a possible redshift variations of intensity of the ultraviolet background by approximately a factor of 2-3 at redshifts z~ 2-3.
Research on High Sensitive D-Shaped FBG Hydrogen Sensors in Power Transformer Oil
Directory of Open Access Journals (Sweden)
Ying-Ting Luo
2016-10-01
Full Text Available Dissolved hydrogen is a symbol gas decomposed by power transformer oil for electrical faults such as overheat or partial discharges. A novel D-shaped fiber Bragg grating (D-FBG sensor is herein proposed and was fabricated with magnetron sputtering to measure the dissolved hydrogen concentration in power transformer oil in this paper. Different from the RI (refractive index-based effect, D-FBG in this case is sensitive to curvature caused by stress from sensing coating, leading to Bragg wavelength shifts accordingly. The relationship between the D-FBG wavelength shift and dissolved hydrogen concentration in oil was measured experimentally in the laboratory. The detected sensitivity could be as high as 1.96 μL/L at every 1-pm wavelength shift. The results proved that a simple, polished FBG-based hydrogen sensor provides a linear measuring characteristic in the range of low hydrogen concentrations in transformer oil. Moreover, the stable hydrogen sensing performance was investigated by X-ray diffraction analysis.
Research on High Sensitive D-Shaped FBG Hydrogen Sensors in Power Transformer Oil.
Luo, Ying-Ting; Wang, Hong-Bin; Ma, Guo-Ming; Song, Hong-Tu; Li, Chengrong; Jiang, Jun
2016-10-04
Dissolved hydrogen is a symbol gas decomposed by power transformer oil for electrical faults such as overheat or partial discharges. A novel D-shaped fiber Bragg grating (D-FBG) sensor is herein proposed and was fabricated with magnetron sputtering to measure the dissolved hydrogen concentration in power transformer oil in this paper. Different from the RI (refractive index)-based effect, D-FBG in this case is sensitive to curvature caused by stress from sensing coating, leading to Bragg wavelength shifts accordingly. The relationship between the D-FBG wavelength shift and dissolved hydrogen concentration in oil was measured experimentally in the laboratory. The detected sensitivity could be as high as 1.96 μL/L at every 1-pm wavelength shift. The results proved that a simple, polished FBG-based hydrogen sensor provides a linear measuring characteristic in the range of low hydrogen concentrations in transformer oil. Moreover, the stable hydrogen sensing performance was investigated by X-ray diffraction analysis.
Institute of Scientific and Technical Information of China (English)
Chun-Chuan Liu; Feng-Ming Li; Ting-Wei Liang; Wen-Hu Huang
2011-01-01
In this paper,wave and vibratory power transmission in a finite L-shaped Mindlin plate with two simply supported opposite edges are investigated using the wave approach.The dynamic responses,active and reactive power flow in the finite plate are calculated by the Mindlin plate theory (MPT) and classic plate theory (CPT).To satisfy the boundary conditions and continuous conditions at the coupled junction of the finite L-shaped plate,the near-field and far-field waves are entirely contained in the wave approach.The in-plane longitudinal and shear waves are also considered.The results indicate that the vibratory power flow based on the MPT is different from that based on the CPT not only at high frequencies but also at low and medium frequencies.The influence of the plate thickness on the vibrational power flow is investigated.From the results it is seen that the shear and rotary inertia correction of the MPT can influence the active and reactive power at the junction of the L-shaped plate not only at high frequencies but also at low and medium frequencies.Furthermore,the effects of structural damping on the active and reactive power flow at the junction are also analyzed.
Wen, Zhen; Yeh, Min-Hsin; Guo, Hengyu; Wang, Jie; Zi, Yunlong; Xu, Weidong; Deng, Jianan; Zhu, Lei; Wang, Xin; Hu, Chenguo; Zhu, Liping; Sun, Xuhui; Wang, Zhong Lin
2016-10-01
Wearable electronics fabricated on lightweight and flexible substrate are believed to have great potential for portable devices, but their applications are limited by the life span of their batteries. We propose a hybridized self-charging power textile system with the aim of simultaneously collecting outdoor sunshine and random body motion energies and then storing them in an energy storage unit. Both of the harvested energies can be easily converted into electricity by using fiber-shaped dye-sensitized solar cells (for solar energy) and fiber-shaped triboelectric nanogenerators (for random body motion energy) and then further stored as chemical energy in fiber-shaped supercapacitors. Because of the all-fiber-shaped structure of the entire system, our proposed hybridized self-charging textile system can be easily woven into electronic textiles to fabricate smart clothes to sustainably operate mobile or wearable electronics.
Institute of Scientific and Technical Information of China (English)
LIU Hai; LIU JinSong; L(U) JianTao; WANG KeJia
2009-01-01
Polarization-dependent difference of the power spectra from a set of two-dimensional (2D) passive random media is investigated by simultaneously solving Maxwell's equations for both transverse magnetic (TM) and transverse electric (TE) fields. The random media have the same random constitution but different shapes. Results show that both two polarized states are morphology dependent,and the variety of the shapes has more influence on the selection of TM polarized modes than that of TE polarized modes. Such polarization-dependent difference of morphology property presents a new modeselecting technique for random lasers.
Directory of Open Access Journals (Sweden)
F Sohbatzadeh
2017-02-01
Full Text Available In this work, we investigated generating argon cold plasma jet at atmospheric pressure based on dielectric barrier discharge configuration using three electrical power supplies of sinusoidal, pulsed and saw tooth high voltage shapes at 8 KHZ. At first; we describe the electronic circuit features for generating high voltage (HV wave forms including saw tooth, sinusoidal and pulsed forms. Then, we consider the effect of voltage shape on the electrical breakdown. Relative concentrations of chemical reactive species such as Oxygen, atomic Nitrogen and OH were measured using optical emission spectroscopy. Using a simple numerical model, we showed a HV with less rise time increases electron density, therefore a cold plasma jet can be produced with a minimal consumption electrical power
Marshall, Najja; Timme, Nicholas M; Bennett, Nicholas; Ripp, Monica; Lautzenhiser, Edward; Beggs, John M
2016-01-01
Neural systems include interactions that occur across many scales. Two divergent methods for characterizing such interactions have drawn on the physical analysis of critical phenomena and the mathematical study of information. Inferring criticality in neural systems has traditionally rested on fitting power laws to the property distributions of "neural avalanches" (contiguous bursts of activity), but the fractal nature of avalanche shapes has recently emerged as another signature of criticality. On the other hand, neural complexity, an information theoretic measure, has been used to capture the interplay between the functional localization of brain regions and their integration for higher cognitive functions. Unfortunately, treatments of all three methods-power-law fitting, avalanche shape collapse, and neural complexity-have suffered from shortcomings. Empirical data often contain biases that introduce deviations from true power law in the tail and head of the distribution, but deviations in the tail have often been unconsidered; avalanche shape collapse has required manual parameter tuning; and the estimation of neural complexity has relied on small data sets or statistical assumptions for the sake of computational efficiency. In this paper we present technical advancements in the analysis of criticality and complexity in neural systems. We use maximum-likelihood estimation to automatically fit power laws with left and right cutoffs, present the first automated shape collapse algorithm, and describe new techniques to account for large numbers of neural variables and small data sets in the calculation of neural complexity. In order to facilitate future research in criticality and complexity, we have made the software utilized in this analysis freely available online in the MATLAB NCC (Neural Complexity and Criticality) Toolbox.
Yavari, Morteza
2014-02-01
The aim of this paper is to generalize the results of the Feoli's formalism (A. Feoli et al., Nucl. Phys. B 705, 577 (2005)) for DNA structures. The exact solutions of the general equilibrium shape equations for a general power model of free energy are investigated using the Feoli's formalism. The free energy of B- to Z-DNA transition is also calculated in this formalism.
Complex unconstrained three-dimensional hand movement and constant equi-affine speed.
Maoz, Uri; Berthoz, Alain; Flash, Tamar
2009-02-01
One long-established simplifying principle behind the large repertoire and high versatility of human hand movements is the two-thirds power law-an empirical law stating a relationship between local geometry and kinematics of human hand trajectories during planar curved movements. It was further generalized not only to various types of human movements, but also to motion perception and prediction, although it was unsuccessful in explaining unconstrained three-dimensional (3D) movements. Recently, movement obeying the power law was proved to be equivalent to moving with constant planar equi-affine speed. Generalizing such motion to 3D space-i.e., to movement at constant spatial equi-affine speed-predicts the emergence of a new power law, whose utility for describing spatial scribbling movements we have previously demonstrated. In this empirical investigation of the new power law, subjects repetitively traced six different 3D geometrical shapes with their hand. We show that the 3D power law explains the data consistently better than both the two-thirds power law and an additional power law that was previously suggested for spatial hand movements. We also found small yet systematic modifications of the power-law's exponents across the various shapes, which further scrutiny suggested to be correlated with global geometric factors of the traced shape. Nevertheless, averaging over all subjects and shapes, the power-law exponents are generally in accordance with constant spatial equi-affine speed. Taken together, our findings provide evidence for the potential role of non-Euclidean geometry in motion planning and control. Moreover, these results seem to imply a relationship between geometry and kinematics that is more complex than the simple local one stipulated by the two-thirds power law and similar models.
Study on welding power source used in intelligent control system for weld pool shape in pulsed GTAW
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
This paper analyses the performance request of arc welding power source used in intelligent control of weld pool shape in pulsed GTAW, and develops a sample power source. The main circuit of the power source takes the structure of single ended inverter with two switches, and takes IGBTs as power switches. The working frequency of the inverter is set at 20(¨)kHz. The control circuit takes PWM circuit as center, and uses single chip computer to complete the manage functions such as the control of working sequence, setting and changing of the welding parameters, sensing of the welding states and communication with outside computer etc. The dynamic reacting time of the whole power is 1(¨)ms, the range of the output current is 5～250(¨)A, the precision of the output current reaches to 1 A. The power strikes arc by contacting workpiece under 5A, and have convenient interface with system computer. All above shows this power source is one with high performance.
Anomalous excitation-power-dependent photoluminescence of InGaAsN/GaAs T-shaped quantum wire
Energy Technology Data Exchange (ETDEWEB)
Klangtakai, Pawinee; Pimanpang, Samuk [Faculty of Science, Department of Physics, Khon Kaen University, 123 Mittraphap Rd., Muang, Khon Kaen, 40002 (Thailand); Nanotec-KKU Center of Excellence on Advanced Nanomaterials for Energy Production and Storage, Khon Kaen, 40002 (Thailand); Integrated Nanotechnology Research Center, Khon Kaen University, Khon Kaen, 40002 (Thailand); Sanorpim, Sakuntam [Faculty of Science, Department of Physics, Chulalongkorn University, Phayathai Rd., Patumwan, Bangkok, 10330 (Thailand); Karlsson, Fredrik; Holtz, Per Olof [Department of Physics, Chemistry, and Biology (IFM), Linkoeping University, 58183, Linkoeping (Sweden); Onabe, Kentaro [Department of Advanced Materials Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8561 (Japan)
2014-08-15
The selected InGaAsN/GaAs T-shaped quantum wire (T-QWR) fabricated by metal organic vapor phase epitaxy has been investigated by microphotoluminescence (μ-PL) and excitation-power-dependent μ-PL. The optical characteristics of one-dimensional structure were taken at low-temperature (4 K) and room temperature (RT) to clarify the intersection of two familiar quantum wells (QWs) in the [001] and [110] directions, named QW1 and QW2, respectively. For the excitation-power-dependent measurement, the intensity of the excitation source was used in the range of 0.001I{sub 0} to I{sub 0}. The result shows that all of emissions related to QW1 and QWR peaks have a nonsymmetric line shape as evidenced by the tailing on the lower-energy side. All peaks shift to higher-energy side (blueshift) with the increase of the excitation power intensity. The blueshift and the low-energy tailing of PL peaks are attributed to the alloying effect. However, the emission peak related to QWR region shows a larger blueshift rate than that of QW1 on increasing of the excitation power intensity. This is an anomalous characteristic for the low-dimensional structure, affected by the large fluctuation state in the QWR region. This fluctuation state is combined of both edges of QWs (QW1 and QW2). (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Demiański, M
2015-01-01
To restore the evolutionary history of the Dark Matter (DM) dominated objects -- galaxies and clusters of galaxies. Analyze the observational data to reveal correlations between the virial mass, $M_{vir}$, of halos and main properties of their central cores, namely, the mean DM density, pressure and entropy, and the redshifts of halo formation, $z_f$. These correlations indicate a high degree of self similarity of both the process of halos formation and the internal structure of relaxed halos. We confirm the CDM--like shape of the small scale power spectrum. However our reconstruction of evolutionary history of observed objects differs from expectations of the standard $\\Lambda$CDM cosmology and requires either multicomponent composition of DM or more complex primordial power spectrum of density perturbations with significant excess of power at scales of clusters of galaxies and larger. This approach seems to be quite efficient and suitably supplements the current investigations of galaxies at large redshifts...
Connecting people to place : Sustainable place-shaping practices as transformative power.
Horlings, Lummina
2016-01-01
The article describes a process of preparing a research design on place-shaping, as outcome of a process of co-design between academic actors and non-academic actors in Brazil, South Africa and The Netherlands, taking place in the context of the project TRANSPLACE. The joint research design addresse
Yi, Fang; Wang, Xiaofeng; Niu, Simiao; Li, Shengming; Yin, Yajiang; Dai, Keren; Zhang, Guangjie; Lin, Long; Wen, Zhen; Guo, Hengyu; Wang, Jie; Yeh, Min-Hsin; Zi, Yunlong; Liao, Qingliang; You, Zheng; Zhang, Yue; Wang, Zhong Lin
2016-06-01
The rapid growth of deformable and stretchable electronics calls for a deformable and stretchable power source. We report a scalable approach for energy harvesters and self-powered sensors that can be highly deformable and stretchable. With conductive liquid contained in a polymer cover, a shape-adaptive triboelectric nanogenerator (saTENG) unit can effectively harvest energy in various working modes. The saTENG can maintain its performance under a strain of as large as 300%. The saTENG is so flexible that it can be conformed to any three-dimensional and curvilinear surface. We demonstrate applications of the saTENG as a wearable power source and self-powered sensor to monitor biomechanical motion. A bracelet-like saTENG worn on the wrist can light up more than 80 light-emitting diodes. Owing to the highly scalable manufacturing process, the saTENG can be easily applied for large-area energy harvesting. In addition, the saTENG can be extended to extract energy from mechanical motion using flowing water as the electrode. This approach provides a new prospect for deformable and stretchable power sources, as well as self-powered sensors, and has potential applications in various areas such as robotics, biomechanics, physiology, kinesiology, and entertainment.
Shehla, Romana; Khan, Athar Ali
2016-01-01
Models with bathtub-shaped hazard function have been widely accepted in the field of reliability and medicine and are particularly useful in reliability related decision making and cost analysis. In this paper, the exponential power model capable of assuming increasing as well as bathtub-shape, is studied. This article makes a Bayesian study of the same model and simultaneously shows how posterior simulations based on Markov chain Monte Carlo algorithms can be straightforward and routine in R. The study is carried out for complete as well as censored data, under the assumption of weakly-informative priors for the parameters. In addition to this, inference interest focuses on the posterior distribution of non-linear functions of the parameters. Also, the model has been extended to include continuous explanatory variables and R-codes are well illustrated. Two real data sets are considered for illustrative purposes.
Kernel Affine Projection Algorithms
Directory of Open Access Journals (Sweden)
José C. Príncipe
2008-05-01
Full Text Available The combination of the famed kernel trick and affine projection algorithms (APAs yields powerful nonlinear extensions, named collectively here, KAPA. This paper is a follow-up study of the recently introduced kernel least-mean-square algorithm (KLMS. KAPA inherits the simplicity and online nature of KLMS while reducing its gradient noise, boosting performance. More interestingly, it provides a unifying model for several neural network techniques, including kernel least-mean-square algorithms, kernel adaline, sliding-window kernel recursive-least squares (KRLS, and regularization networks. Therefore, many insights can be gained into the basic relations among them and the tradeoff between computation complexity and performance. Several simulations illustrate its wide applicability.
Kernel Affine Projection Algorithms
Liu, Weifeng; Príncipe, José C.
2008-12-01
The combination of the famed kernel trick and affine projection algorithms (APAs) yields powerful nonlinear extensions, named collectively here, KAPA. This paper is a follow-up study of the recently introduced kernel least-mean-square algorithm (KLMS). KAPA inherits the simplicity and online nature of KLMS while reducing its gradient noise, boosting performance. More interestingly, it provides a unifying model for several neural network techniques, including kernel least-mean-square algorithms, kernel adaline, sliding-window kernel recursive-least squares (KRLS), and regularization networks. Therefore, many insights can be gained into the basic relations among them and the tradeoff between computation complexity and performance. Several simulations illustrate its wide applicability.
Knowledge, Power and Meanings Shaping Quality Assurance in Higher Education: A Systemic Critique
Houston, Don; Paewai, Shelley
2013-01-01
Internationally, quality assurance schemes persist despite long-standing dissatisfaction and critique of their impact and outcomes. Adopting a critical systems perspective, the article explores the relationships between the knowledge, power and meanings that stakeholder groups bring to the design and implementation of quality assurance systems.…
Power Shaping : A New Paradigm for Stabilization of Nonlinear RLC Circuits
Ortega, Romeo; Jeltsema, Dimitri; Scherpen, Jacquelien M.A.
2002-01-01
In this paper we prove that for a class of RLC circuits with convex energy function and weak electromagnetic coupling it is possible to “add a differentiation” to the port terminals preserving passivity—with a new storage function that is directly related to the circuit power. The result is of inter
Effects of axial power shapes on CHF locations in a single tube and in rod bundle assemblies
Energy Technology Data Exchange (ETDEWEB)
Han, B.; Yang, B.W.; Zhang, H.; Zha, Y.; Zhang, Y. [Xi' an Jiaotong Univ. (China). School of Nuclear Science and Technology
2016-07-15
Currently, the prediction of rod bundle CHF is dependent on CHF correlations derived from CHF data. A simple correction factor, such as F-factor, is often used to account for the axial power shape differences based on a simple accumulated energy concept, which has totally no consideration on the impact of true local condition on CHF mechanism. Subsequently, as expected, large uncertainty is often associated with the CHF value and CHF location predictions. For the purpose of obtaining different power shapes effects on CHF, CFD calculated parameter values were used to predict the possible CHF occurrence location. The possible CHF location prediction method proposed in this paper is calculated void fraction, heat transfer coefficient (HTC), liquid temperature distribution and detailed local parameters. And the uniform and non-uniform CHF were analyzed. The prediction of possible CHF locations in a 5 x 5 rod bundle may provide useful information for the design of a full-length CHF test, enhance the accuracy of CHF and CHF location prediction, and reduce the costs of the experimentation.
Gonçalves, Ricardo; Carvalho, Nuno B.; Pinho, Pedro
2017-02-01
In the current contest of wireless systems, the last frontier remains the cut of the power cord. In that sense, the interest over wireless energy transfer technologies in the past years has grown exponentially. However, there are still many challenges to be overcome in order to enable wireless energy transfer full potential. One of the focus in the development of such systems is the design of very-high-gain, highly efficient, antennas that can compensate for the propagation loss of radio signals over the air. In this paper, we explore the design and manufacturing process of dielectric lenses, fabricated using a professional-grade desktop 3D printer. Lens antennas are used in order to increase beam efficiency and therefore maximize the efficiency of a wireless power-transfer system operating at microwave frequencies in the Ku band. Measurements of two fabricated prototypes showcase a large directivity, as predicted with simulations. xml:lang="fr"
Study on the beam shaping of high-power laser diode bars
Institute of Scientific and Technical Information of China (English)
Wei Huang(黄伟); Xiaodong Zeng(曾晓东); Yuying An(安毓英)
2003-01-01
Based on the Collins form, the intensity distribution of the resulting beam is derived when Gaussian beamsof a high-power laser diode bar pass through a paraxial optical system. Then flattop beam profiles areobtained by a concave cylindrical lens, and the propagation properties are discussed in detail, such as thepeak-intensity axis inclined at an angle γi. In addition, an expression to calculate beam angular width ispresented.
Directory of Open Access Journals (Sweden)
Steven J. Gortler
2013-12-01
Full Text Available We study the properties of affine rigidity of a hypergraph and prove a variety of fundamental results. First, we show that affine rigidity is a generic property (i.e., depends only on the hypergraph, not the particular embedding. Then we prove that a graph is generically neighborhood affinely rigid in d-dimensional space if it is (d+1-vertex-connected. We also show neighborhood affine rigidity of a graph implies universal rigidity of its squared graph. Our results, and affine rigidity more generally, have natural applications in point registration and localization, as well as connections to manifold learning.
Directory of Open Access Journals (Sweden)
LARISSA BǍTRÂNCEA
2014-06-01
Full Text Available Tax literature acknowledges that trust in authorities and power of authorities, as grassroots dimensions of the “slippery slope framework”, influence compliance behavior. The present material assesses the framework’s main dimensions in the case of the Mediterranean tax climate (i.e., Cyprus, Greece, Italy, Portugal and Spain by a manifold of economic, financial and psychological variables. The proposed rationale, including World Bank governance indicators (government effectiveness, rule of law, regulatory quality, control for corruption as proxies for the framework’s dimensions, analyses of chain base indexes with respect to economic performance (calculations involving GDP per capita, quantitative evaluation of tax compliance burden and cost of taxation (calculations involving Paying Taxes reports, aims at raising awareness among policy makers and citizens about relevance of trust and power for compliance behavior within the Mediterranean tax climate. Multidisciplinary estimations of trust and power may constitute a benchmark for decision makers in appraising the effects generated by the measures countervailing crises and in designing strategies to hinder future undesirable economic bouts.
Energy Technology Data Exchange (ETDEWEB)
Wilson, David G.; Robinett, Rush D. III [Sandia National Laboratories, Albuquerque, NM (United States). Energy, Resources and Systems Analysis Center
2010-07-01
The swing equations for renewable generators connected to the grid are developed and a simple wind turbine with UPFC is used as an example. The swing equations for renewable generator are formulated as a natural Hamiltonian system with externally applied non-conservative forces. A two-step process referred to as Hamiltonian Surface Shaping and Power Flow Control (HSSPFC) is used to analyze and design feedback controllers for the renewable generators system. This formulation extends previous results on the analytical verification of the Potential Energy Boundary Surface (PEBS) method to nonlinear control analysis and design and justifies the decomposition of the system into conservative and nonconservative systems to enable a two-step, serial analysis and design procedure. This paper presents the analysis and numerical simulation results for a nonlinear control design example that includes the One-Machine Infinite Bus (OMIB) system with a Unified Power Flow Control (UPEC) and applied to a simplified wind turbine generator. The needed power and energy storage/charging responses are also determined. (orig.)
Statistical characteristics of observed Ly-$\\alpha$ forest and the shape of linear power spectrum
Demianski, M
2005-01-01
Properties of $\\sim$ 6 000 Ly-$\\alpha$ absorbers observed in 19 high resolution spectra of QSOs are investigated using the model of formation and evolution of DM structure elements based on the Zel'dovich theory. This model asserts that absorbers are formed in the course of both linear and nonlinear adiabatic or shock compression of dark matter (DM) and gaseous matter. It allows us to link the column density and overdensity of DM and gaseous components with the observed column density of neutral hydrogen, redshifts and Doppler parameters of absorbers and demonstrates that at high redshifts we observe a self similar period of structure evolution with the Gaussian initial perturbations. We show that the colder absorbers are associated with rapidly expanded regions of a galactic scale which represent large amplitude negative density perturbations. We extend and improve the method of measuring the power spectrum of initial perturbations proposed in Demia\\'nski & Doroshkevich (2003b). Our method links the obse...
Enhanced Cell-Edge Performance with Transmit Power-Shaping and Multipoint, Multiflow Techniques
Institute of Scientific and Technical Information of China (English)
Philip Pietrask; Gregg Charltonl; Rui Yang,; Carl Wang
2011-01-01
In this paper, we present a technique called ＂fuzzy cells＂ that builds on the multicarrier features of Long Term Evolution-Advanced （LTE-A） and high-speed packet access （HSPA）. Multiple carriers are aggregated to create a larger system bandwidth, and these carriers are transmitted at different powers by each sector antenna. This creates a set of cell-edge locations that differ from one frequency to the next. System-level simulations are performed to estimate individual user and average throughput for a hexagonal deployment of 3-sector base stations. For moderately high loads, a fuzzy cell deployment can improve tenth percentile （cell-edge） user throughput by 100% and can improve average throughput by about 30% compared with a reuse 1 scheme. Fuzzy ceils reduce inter-cell interference in the same way as higher-order reuse schemes and allow users to access the full system bandwidth.
Statistical characteristics of observed Ly-$\\alpha$ forest and the shape of initial power spectrum
Demianski, M
2002-01-01
Properties of $\\sim$ 5000 observed Ly-$\\alpha$ absorbers are investigated using the model of formation and evolution of DM structure elements based on the Zel'dovich theory. This model is generally consistent with simulations of absorbers formation, accurately describes the Large Scale Structure observed in the galaxy distribution at small redshifts and emphasizes the generic similarity of the LSS and absorbers. The simple physical model of absorbers asserts that they are composed of DM and gaseous matter and it allows us to estimate the column density and overdensity of DM and gaseous components and the entropy of the gas trapped within the DM potential wells. The parameters of DM component are found to be consistent with theoretical expectations for the Gaussian initial perturbations with the WDM--like power spectrum. We demonstrate the influence of the main physical factors responsible for the absorbers evolution. The analysis of redshift distribution of absorbers confirms the self consistence of the assum...
Chen, Jian; Li, Peng; Song, Gangbing; Ren, Zhang
2017-01-01
The design of a super-capacitor-powered shape-memory-alloy (SMA) actuated accumulator for blowout preventer (BOP) presented in this paper featured several advantages over conventional hydraulic accumulators including instant large current drive, quick system response and elimination of need for the pressure conduits. However, the mechanical design introduced two challenges, the nonlinear nature of SMA actuators and the varying voltage provided by a super capacitor, for control system design. A cerebellar model articulation controller (CMAC) feedforward plus PID controller was developed with the aim of compensation for these adverse effects. Experiments were conducted on a scaled down model and experimental results show that precision control can be achieved with the proposed configurations and algorithms.
Statistical characteristics of the observed Lyα forest and the shape of the initial power spectrum
Demiański, M.; Doroshkevich, A. G.; Turchaninov, V. I.
2006-09-01
We analyse the basic properties of about 6000 Lyman α absorbers observed in the high-resolution spectra of 19 quasars. We compare their observed characteristics with the predictions of our model of formation and evolution of absorbers and dark matter (DM) pancakes and voids based on the Zel'dovich theory of gravitational instability. This model asserts that absorbers are formed in the course of both linear and non-linear adiabatic and shock compression of DM and gaseous matter. Our model is consistent with simulations of structure formation, describes reasonably well the large-scale structure (LSS) observed in the distribution of galaxies at small redshifts, and emphasizes the generic similarity of the process of formation of LSS and absorbers. Using this model, we are able to link the column density and overdensity of the DM and gaseous components with the observed column density of neutral hydrogen, redshifts and Doppler parameters of absorbers. We show that the colder absorbers are associated with rapidly expanded underdense regions of galactic scale. We extend an existing method of measuring the power spectrum of initial perturbations. The observed separations between absorbers and their DM column density are linked with the correlation function of the initial velocity field. Applying this method to our sample of absorbers, we recover the cold dark matter (CDM) like power spectrum at scales of 10h-1 >= D >= 0.15h-1Mpc with a precision of ~15 per cent. However, at scales of ~3-150h-1kpc, the measured and CDM-like spectra are different. This result suggests a possible complex inflation with generation of excess power at small scales. Both confirmation of the CDM-like shape of the initial power spectrum and detection of its distortions at small scales are equally important for the widely discussed problems of physics of the early Universe, galaxy formation, and reheating of the Universe.
Gultekin, Kemal
2015-01-01
In this study, we give a thorough analysis of a general affine gravity with torsion. After a brief exposition of the affine gravities considered by Eddington and Schroedinger, we construct and analyze different affine gravities based on determinants of the Ricci tensor, torsion tensor, Riemann tensor and their combinations. In each case we reduce equations of motion to their simplest forms and give a detailed analysis of their solutions. Our analyses lead to construction of the affine connection in terms of curvature and torsion tensors. Our solutions of the dynamical equations show that curvature tensors at different points are correlated via non-local, exponential rescaling factors determined by the torsion tensor.
Directory of Open Access Journals (Sweden)
AHMER ALI
2013-02-01
Full Text Available In recent years steel-concrete composite shear walls have been widely used in enormous high-rise buildings. Due to high strength and ductility, enhanced stiffness, stable cycle characteristics and large energy absorption, such walls can be adopted in the auxiliary building; surrounding the reactor containment structure of nuclear power plants to resist lateral forces induced by heavy winds and severe earthquakes. This paper demonstrates a set of nonlinear numerical studies on I-shaped composite steel-concrete shear walls of the nuclear power plants subjected to reverse cyclic loading. A three-dimensional finite element model is developed using ABAQUS by emphasizing on constitutive material modeling and element type to represent the real physical behavior of complex shear wall structures. The analysis escalates with parametric variation in steel thickness sandwiching the stipulated amount of concrete panels. Modeling details of structural components, contact conditions between steel and concrete, associated boundary conditions and constitutive relationships for the cyclic loading are explained. Later, the load versus displacement curves, peak load and ultimate strength values, hysteretic characteristics and deflection profiles are verified with experimental data. The convergence of the numerical outcomes has been discussed to conclude the remarks.
Heegaard, Niels H H
2009-06-01
The journal Electrophoresis has greatly influenced my approaches to biomolecular affinity studies. The methods that I have chosen as my main tools to study interacting biomolecules--native gel and later capillary zone electrophoresis--have been the topic of numerous articles in Electrophoresis. Below, the role of the journal in the development and dissemination of these techniques and applications reviewed. Many exhaustive reviews on affinity electrophoresis and affinity CE have been published in the last few years and are not in any way replaced by the present deliberations that are focused on papers published by the journal.
Energy Technology Data Exchange (ETDEWEB)
Gueltekin, Kemal [Izmir Institute of Technology, Department of Physics, Izmir (Turkey)
2016-03-15
In this study, we give a thorough analysis of a general affine gravity with torsion. After a brief exposition of the affine gravities considered by Eddington and Schroedinger, we construct and analyze different affine gravities based on the determinants of the Ricci tensor, the torsion tensor, the Riemann tensor, and their combinations. In each case we reduce equations of motion to their simplest forms and give a detailed analysis of their solutions. Our analyses lead to the construction of the affine connection in terms of the curvature and torsion tensors. Our solutions of the dynamical equations show that the curvature tensors at different points are correlated via non-local, exponential rescaling factors determined by the torsion tensor. (orig.)
Shi, Qinqin
2016-03-21
An efficient iodination reaction of electron-deficient heterocycles is described. The reaction utilizes KOtBu as an initiator and likely proceeds by a radical anion propagation mechanism. This new methodology is particularly effective for functionalization of building blocks for electron transport materials. Its utility is demonstrated with the synthesis of a new perylenediimide-thiazole non-fullerene acceptor capable of delivering a power conversion efficiency of 4.5% in a bulk-heterojunction organic solar cell. © 2016 American Chemical Society.
Indefinite Affine Hyperspheres Admitting a Pointwise Symmetry. Part 2
Directory of Open Access Journals (Sweden)
Christine Scharlach
2009-10-01
Full Text Available An affine hypersurface M is said to admit a pointwise symmetry, if there exists a subgroup G of Aut(T_pM for all p in M, which preserves (pointwise the affine metric h, the difference tensor K and the affine shape operator S. Here, we consider 3-dimensional indefinite affine hyperspheres, i.e. S = HId (and thus S is trivially preserved. In Part 1 we found the possible symmetry groups G and gave for each G a canonical form of K. We started a classification by showing that hyperspheres admitting a pointwise Z_2 × Z_2 resp. R-symmetry are well-known, they have constant sectional curvature and Pick invariant J < 0 resp. J = 0. Here, we continue with affine hyperspheres admitting a pointwise Z_3- or SO(2-symmetry. They turn out to be warped products of affine spheres (Z_3 or quadrics (SO(2 with a curve.
Minguzzi, E.
2016-11-01
We investigate spacetimes whose light cones could be anisotropic. We prove the equivalence of the structures: (a) Lorentz-Finsler manifold for which the mean Cartan torsion vanishes, (b) Lorentz-Finsler manifold for which the indicatrix (observer space) at each point is a convex hyperbolic affine sphere centered on the zero section, and (c) pair given by a spacetime volume and a sharp convex cone distribution. The equivalence suggests to describe (affine sphere) spacetimes with this structure, so that no algebraic-metrical concept enters the definition. As a result, this work shows how the metric features of spacetime emerge from elementary concepts such as measure and order. Non-relativistic spacetimes are obtained replacing proper spheres with improper spheres, so the distinction does not call for group theoretical elements. In physical terms, in affine sphere spacetimes the light cone distribution and the spacetime measure determine the motion of massive and massless particles (hence the dispersion relation). Furthermore, it is shown that, more generally, for Lorentz-Finsler theories non-differentiable at the cone, the lightlike geodesics and the transport of the particle momentum over them are well defined, though the curve parametrization could be undefined. Causality theory is also well behaved. Several results for affine sphere spacetimes are presented. Some results in Finsler geometry, for instance in the characterization of Randers spaces, are also included.
D.F. Schrager
2006-01-01
We propose a new model for stochastic mortality. The model is based on the literature on affine term structure models. It satisfies three important requirements for application in practice: analytical tractibility, clear interpretation of the factors and compatibility with financial option pricing m
Kim, Se-Hee; Choi, Keun-Ho; Cho, Sung-Ju; Choi, Sinho; Park, Soojin; Lee, Sang-Young
2015-08-12
Forthcoming flexible/wearable electronic devices with shape diversity and mobile usability garner a great deal of attention as an innovative technology to bring unprecedented changes in our daily lives. From the power source point of view, conventional rechargeable batteries (one representative example is a lithium-ion battery) with fixed shapes and sizes have intrinsic limitations in fulfilling design/performance requirements for the flexible/wearable electronics. Here, as a facile and efficient strategy to address this formidable challenge, we demonstrate a new class of printable solid-state batteries (referred to as "PRISS batteries"). Through simple stencil printing process (followed by ultraviolet (UV) cross-linking), solid-state composite electrolyte (SCE) layer and SCE matrix-embedded electrodes are consecutively printed on arbitrary objects of complex geometries, eventually leading to fully integrated, multilayer-structured PRISS batteries with various form factors far beyond those achievable by conventional battery technologies. Tuning rheological properties of SCE paste and electrode slurry toward thixotropic fluid characteristics, along with well-tailored core elements including UV-cured triacrylate polymer and high boiling point electrolyte, is a key-enabling technology for the realization of PRISS batteries. This process/material uniqueness allows us to remove extra processing steps (related to solvent drying and liquid-electrolyte injection) and also conventional microporous separator membranes, thereupon enabling the seamless integration of shape-conformable PRISS batteries (including letters-shaped ones) into complex-shaped objects. Electrochemical behavior of PRISS batteries is elucidated via an in-depth analysis of cell impedance, which provides a theoretical basis to enable sustainable improvement of cell performance. We envision that PRISS batteries hold great promise as a reliable and scalable platform technology to open a new concept of cell
Control and estimation of piecewise affine systems
Xu, Jun
2014-01-01
As a powerful tool to study nonlinear systems and hybrid systems, piecewise affine (PWA) systems have been widely applied to mechanical systems. Control and Estimation of Piecewise Affine Systems presents several research findings relating to the control and estimation of PWA systems in one unified view. Chapters in this title discuss stability results of PWA systems, using piecewise quadratic Lyapunov functions and piecewise homogeneous polynomial Lyapunov functions. Explicit necessary and sufficient conditions for the controllability and reachability of a class of PWA systems are
Self-Affinity, Self-Similarity and Disturbance of Soil Seed Banks by Tillage.
Dias, Luís S
2013-07-05
Soil seed banks were sampled in undisturbed soil and after soil had been disturbed by tillage (tine, harrow or plough). Seeds were sorted by size and shape, and counted. Size-number distributions were fitted by power law equations that allowed the identification of self-similarity and self-affinity. Self-affinity and thus non-random size-number distribution prevailed in undisturbed soil. Self-similarity and thus randomness of size-number distribution prevailed after tillage regardless of the intensity of disturbance imposed by cultivation. The values of fractal dimensions before and after tillage were low, suggesting that short-term, short-range factors govern size-number distribution of soil seed banks.
Directory of Open Access Journals (Sweden)
Julia Arias-Martorell
Full Text Available The postcranial evidence for the Australopithecus genus indicates that australopiths were able bipeds; however, the morphology of the forelimbs and particularly that of the shoulder girdle suggests that they were partially adapted to an arboreal lifestyle. The nature of such arboreal adaptations is still unclear, as are the kind of arboreal behaviors in which australopiths might have engaged. In this study we analyzed the shape of the shoulder joint (proximal humerus and glenoid cavity of the scapula of three australopith specimens: A.L. 288-1 (A. afarensis, Sts 7 (A. africanus and Omo 119-73-2718 (Australopithecus sp. with three-dimensional geometric morphometrics. The morphology of the specimens was compared with that of a wide array of living anthropoid taxa and some additional fossil hominins (the Homo erectus specimen KNM-WT 15000 and the H. neanderthalensis specimen Tabun 1. Our results indicate that A.L. 288-1 shows mosaic traits resembling H. sapiens and Pongo, whereas the Sts 7 shoulder is most similar to the arboreal apes and does not present affinities with H. sapiens. Omo 119-73-2718 exhibits morphological affinities with the more arboreal and partially suspensory New World monkey Lagothrix. The shoulder of the australopith specimens thus shows a combination of primitive and derived traits (humeral globularity, enhancement of internal and external rotation of the joint, related to use of the arm in overhead positions. The genus Homo specimens show overall affinities with H. sapiens at the shoulder, indicating full correspondence of these hominin shoulders with the modern human morphotype.
Arias-Martorell, Julia; Potau, Josep Maria; Bello-Hellegouarch, Gaëlle; Pérez-Pérez, Alejandro
2015-01-01
The postcranial evidence for the Australopithecus genus indicates that australopiths were able bipeds; however, the morphology of the forelimbs and particularly that of the shoulder girdle suggests that they were partially adapted to an arboreal lifestyle. The nature of such arboreal adaptations is still unclear, as are the kind of arboreal behaviors in which australopiths might have engaged. In this study we analyzed the shape of the shoulder joint (proximal humerus and glenoid cavity of the scapula) of three australopith specimens: A.L. 288–1 (A. afarensis), Sts 7 (A. africanus) and Omo 119–73–2718 (Australopithecus sp.) with three-dimensional geometric morphometrics. The morphology of the specimens was compared with that of a wide array of living anthropoid taxa and some additional fossil hominins (the Homo erectus specimen KNM-WT 15000 and the H. neanderthalensis specimen Tabun 1). Our results indicate that A.L. 288–1 shows mosaic traits resembling H. sapiens and Pongo, whereas the Sts 7 shoulder is most similar to the arboreal apes and does not present affinities with H. sapiens. Omo 119–73–2718 exhibits morphological affinities with the more arboreal and partially suspensory New World monkey Lagothrix. The shoulder of the australopith specimens thus shows a combination of primitive and derived traits (humeral globularity, enhancement of internal and external rotation of the joint), related to use of the arm in overhead positions. The genus Homo specimens show overall affinities with H. sapiens at the shoulder, indicating full correspondence of these hominin shoulders with the modern human morphotype. PMID:25651542
Affine and degenerate affine BMW algebras: The center
Daugherty, Zajj; Virk, Rahbar
2011-01-01
The degenerate affine and affine BMW algebras arise naturally in the context of Schur-Weyl duality for orthogonal and symplectic Lie algebras and quantum groups, respectively. Cyclotomic BMW algebras, affine Hecke algebras, cyclotomic Hecke algebras, and their degenerate versions are quotients. In this paper the theory is unified by treating the orthogonal and symplectic cases simultaneously; we make an exact parallel between the degenerate affine and affine cases via a new algebra which takes the role of the affine braid group for the degenerate setting. A main result of this paper is an identification of the centers of the affine and degenerate affine BMW algebras in terms of rings of symmetric functions which satisfy a "cancellation property" or "wheel condition" (in the degenerate case, a reformulation of a result of Nazarov). Miraculously, these same rings also arise in Schubert calculus, as the cohomology and K-theory of isotropic Grassmanians and symplectic loop Grassmanians. We also establish new inte...
Hierarchical Affinity Propagation
Givoni, Inmar; Frey, Brendan J
2012-01-01
Affinity propagation is an exemplar-based clustering algorithm that finds a set of data-points that best exemplify the data, and associates each datapoint with one exemplar. We extend affinity propagation in a principled way to solve the hierarchical clustering problem, which arises in a variety of domains including biology, sensor networks and decision making in operational research. We derive an inference algorithm that operates by propagating information up and down the hierarchy, and is efficient despite the high-order potentials required for the graphical model formulation. We demonstrate that our method outperforms greedy techniques that cluster one layer at a time. We show that on an artificial dataset designed to mimic the HIV-strain mutation dynamics, our method outperforms related methods. For real HIV sequences, where the ground truth is not available, we show our method achieves better results, in terms of the underlying objective function, and show the results correspond meaningfully to geographi...
Affinity driven social networks
Ruyú, B.; Kuperman, M. N.
2007-04-01
In this work we present a model for evolving networks, where the driven force is related to the social affinity between individuals of a population. In the model, a set of individuals initially arranged on a regular ordered network and thus linked with their closest neighbors are allowed to rearrange their connections according to a dynamics closely related to that of the stable marriage problem. We show that the behavior of some topological properties of the resulting networks follows a non trivial pattern.
Skirzewski, Aureliano
2014-01-01
We develop a topological theory of gravity with torsion where metric has a dynamical rather than a kinematical origin. This approach towards gravity resembles pre-geometrical approaches in which a fundamental metric does not exist, but the affine connection gives place to a local inertial structure. Such feature reminds us of Mach's principle, that assumes the inertial forces should have dynamical origin. Additionally, a Newtonian gravitational force is obtained in the non-relativistic limit of the theory.
Affine morphisms at zero level
Das, Paramita; Gupta, Ved Prakash
2010-01-01
Given a finite index subfactor, we show that the {\\em affine morphisms at zero level} in the affine category over the planar algebra associated to the subfactor is isomorphic to the fusion algebra of the subfactor as a *-algebra.
On the Affine Isoperimetric Inequalities
Indian Academy of Sciences (India)
Wuyang Yu; Gangsong Leng
2011-11-01
We obtain an isoperimetric inequality which estimate the affine invariant -surface area measure on convex bodies. We also establish the reverse version of -Petty projection inequality and an affine isoperimetric inequality of $_{-p}K$.
Ramos, Paweł; Pieprzyca, Małgorzata; Pilawa, Barbara
2016-01-01
Complex free radical system in thermally sterilized acidum boricum (AB) was studied. Acidum boricum was sterilized at temperatures and times given by pharmaceutical norms: 160 degrees C and 120 min, 170 degrees C and 60 min and 180 degrees C and 30 min. The advanced spectroscopic tests were performed. The EPR spectra of free radicals were measured as the first derivatives with microwaves of 9.3 GHz frequency and magnetic modulation of 100 kHz. The Polish X-band electron paramagnetic resonance spectrometer of Radiopan (Poznań) was used. EPR lines were not observed for the nonheated AB. The broad EPR asymmetric lines were obtained for all the heated AB samples. The influence of microwave power in the range of 2.2-70 mW on the shape of EPR spectra of the heated drug samples was tested. The following asymmetry parameters: A1/A2, A1-A2, B1/B2, and B1-B2, were analyzed. The changes of these parameters with microwave power were observed. The strong dependence of shape and its parameters on microwave power proved the complex character of free radical system in thermally sterilized AB. Changes of microwave power during the detection of EPR spectra indicated complex character of free radicals in AB sterilized in hot air under all the tested conditions. Thermolysis, interactions between free radicals and interactions of free radicals with oxygen may be responsible for the complex free radicals system in thermally treated AB. Usefulness of continuous microwave saturation of EPR lines and shape analysis to examine free radicals in thermally sterilized drugs was confirmed.
Affine Patches on Positroid Varieties and Affine Pipe Dreams (Thesis)
Snider, Michelle
2010-01-01
The objects of interest in this thesis are positroid varieties in the Grassmannian, which are indexed by juggling patterns. In particular, we study affine patches on these positroid varieties. Our main result corresponds these affine patches to Kazhdan-Lusztig varieties in the affine Grassmannian. We develop a new term order and study how these spaces are related to subword complexes and Stanley-Reisner ideals. We define an extension of pipe dreams to the affine case and conclude by showing how our affine pipe dreams are generalizations of Cauchon and Le diagrams.
Affine and quasi-affine frames for rational dilations
DEFF Research Database (Denmark)
Bownik, Marcin; Lemvig, Jakob
2011-01-01
, the corresponding family of quasi-affine systems are frames with uniform frame bounds. We also prove a similar equivalence result between pairs of dual affine frames and dual quasi-affine frames. Finally, we uncover some fundamental differences between the integer and rational settings by exhibiting an example......In this paper we extend the investigation of quasi-affine systems, which were originally introduced by Ron and Shen [J. Funct. Anal. 148 (1997), 408-447] for integer, expansive dilations, to the class of rational, expansive dilations. We show that an affine system is a frame if, and only if...
High-Power Microwave Metamaterials for Phased-Array, anti-HPM, and Pulse-Shaping Applications
2014-07-23
amplifiers was investigated and a new concept for designing high-power, millimeter - wave traveling wave tubes was introduced and verified using computer-based...large aperture size in a full- wave electromagnetic simulation tool. Using this procedure, a prototype multi-beam antenna operating in the 8-10 GHz...papers [C9], [C10]. 13 7. Metamaterial-Enhanced Traveling Wave Tubes The growing need for high power sources at millimeter - wave (MMW
Affinity Purification of Insulin by Peptide-Ligand Affinity Chromatography
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
The affinity heptapeptide (HWWWPAS) for insulin, selected from phage display library,was coupled to EAH Sepharose 4B gel and packed to a 1-mL column. The column was used for the affinity purification of insulin from protein mixture and commercial insulin preparation. It was observed that the minor impurity in the commercial insulin was removed by the affinity chromatography. Nearly 40 mg of insulin could be purified with the 1-mL affinity column. The results revealed the high specificity and capacity of the affinity column for insulin purification. Moreover, based on the analysis of the amino acids in the peptide sequence, shorter peptides were designed and synthesized for insulin chromatography. As a result, HWWPS was found to be a good alternative to HWWWPAS, while the other two peptides with three or four amino acids showed weak affinity for insulin. The results indicated that the peptide sequence of HWWWPAS was quite conservative for specific binding of insulin.
Jacobi Structures on Affine Bundles
Institute of Scientific and Technical Information of China (English)
J. GRABOWSKI; D. IGLESIAS; J. C. MARRERO; E. PADR(O)N; P. URBA(N)SKI
2007-01-01
We study affine Jacobi structures (brackets) on an affine bundle π: A→M, i.e. Jacobi brackets that close on affine functions. We prove that if the rank of A is non-zero, there is a one-to- one correspondence between affine Jacobi structures on A and Lie algebroid structures on the vector bundle A+=∪p∈M Aff(Ap, R) of affine functionals. In the case rank A = 0, it is shown that there is a one-to-one correspondence between affins Jacobi structures on A and local Lie algebras on A+. Some examples and applications, also for the linear case, are discussed. For a special type of affine Jacobi structures which are canonically exhibited (strongly-affine or affine-homogeneous Jacobi structures) over a real vector space of finite dimension, we describe the leaves of its characteristic foliation as the orbits of an affine representation. These afline Jacobi structures can be viewed as an analog of the Kostant-Arnold-LiouviUe linear Poisson structure on the dual space of a real finite-dimensional Lie algebra.
Wang, Peng; Li, Xiao; Shang, YaPing; Xu, XiaoJun
2015-10-01
The fiber laser has very obvious advantages and broad applications in remote welding, 3D cutting and national defense compared with the traditional solid laser. But influenced by heat effect of gain medium, nonlinear effect, stress birefringence effect and other negative factors, it's very difficult to get high power linearly polarized laser just using a single laser. For these limitations a polarization-converting system is designed using beam shaping and combination technique which is able to transform naturally polarized laser to linearly polarized laser at real time to resolve difficulties of generating high-power linearly polarized laser from fiber lasers in this paper. The principle of the Gaussian beam changing into the hollow beam passing through two axicons and the combination of the Gaussian beam and the hollow beam is discussed. In the experimental verification the energy conversion efficiency reached 93.1% with a remarkable enhancement of the extinction ratio from 3% to 98% benefited from the high conversion efficiency of axicons and the system worked fine under high power conditions. The system also kept excellent far field divergence. The experiment phenomenon also agreed with the simulation quite well. The experiment proves that this polarization-converting system will not affect laser structure which controls easily and needs no feedback and controlling system with stable and reliable properties at the same time. It can absolutely be applied to the polarization-conversion of high power laser.
Qureshi, M S; Sheikh, Q I; Hill, R; Brown, P E; Dickman, M J; Tzokov, S B; Rice, D W; Gjerde, D T; Hornby, D P
2013-08-01
The isolation of complex macromolecular assemblies at the concentrations required for structural analysis represents a major experimental challenge. Here we present a method that combines the genetic power of site-specific recombination in order to selectively "tag" one or more components of a protein complex with affinity-based rapid filtration and a final step of capillary-based enrichment. This modified form of tandem affinity purification produces highly purified protein complexes at high concentrations in a highly efficient manner. The application of the method is demonstrated for the yeast Arp2/3 heptameric protein complex involved in mediating reorganization of the actin cytoskeleton.
Adjoint affine fusion and tadpoles
Urichuk, Andrew; Walton, Mark A.
2016-06-01
We study affine fusion with the adjoint representation. For simple Lie algebras, elementary and universal formulas determine the decomposition of a tensor product of an integrable highest-weight representation with the adjoint representation. Using the (refined) affine depth rule, we prove that equally striking results apply to adjoint affine fusion. For diagonal fusion, a coefficient equals the number of nonzero Dynkin labels of the relevant affine highest weight, minus 1. A nice lattice-polytope interpretation follows and allows the straightforward calculation of the genus-1 1-point adjoint Verlinde dimension, the adjoint affine fusion tadpole. Explicit formulas, (piecewise) polynomial in the level, are written for the adjoint tadpoles of all classical Lie algebras. We show that off-diagonal adjoint affine fusion is obtained from the corresponding tensor product by simply dropping non-dominant representations.
Adjoint affine fusion and tadpoles
Urichuk, Andrew
2016-01-01
We study affine fusion with the adjoint representation. For simple Lie algebras, elementary and universal formulas determine the decomposition of a tensor product of an integrable highest-weight representation with the adjoint representation. Using the (refined) affine depth rule, we prove that equally striking results apply to adjoint affine fusion. For diagonal fusion, a coefficient equals the number of nonzero Dynkin labels of the relevant affine highest weight, minus 1. A nice lattice-polytope interpretation follows, and allows the straightforward calculation of the genus-1 1-point adjoint Verlinde dimension, the adjoint affine fusion tadpole. Explicit formulas, (piecewise) polynomial in the level, are written for the adjoint tadpoles of all classical Lie algebras. We show that off-diagonal adjoint affine fusion is obtained from the corresponding tensor product by simply dropping non-dominant representations.
Yang, Po Kang
2015-05-15
A flexible triboelectric nanogenerator (FTENG) based on wavy-structured Kapton film and a serpentine electrode on stretchable substrates is presented. The as-fabricated FTENG is capable of harvesting ambient mechanical energy via both compressive and stretching modes. Moreover, the FTENG can be a bendable power source to work on curved surfaces; it can also be adaptively attached onto human skin for monitoring gentle body motions. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Directory of Open Access Journals (Sweden)
Miladinović Slobodan M.
2003-01-01
Full Text Available In the second part of this paper are analyzed effecting of main channels of social mobility for ascent on elite's positions in Serbia and Croatia. Special attention was paid to education and political activity. Survey data says that the patterns of ideological desirable social origin were developed in pattern of ideological desirable developing way of building individual career of members of power elite's across the time. Special importance in that process had high education acquirement. Political activity was necessary follower in the way of advance to the highest social positions. There was used log-linear analyze (hierarchical method because finding statistical importance between presented factors of education and political activity. Thanks to this method we can see details of complex relations of interdependence of this factors.
DEFF Research Database (Denmark)
Elmholdt, Claus Westergård; Fogsgaard, Morten
2016-01-01
In this chapter, we will explore the dynamics of power in processes of creativity, and show its paradoxical nature as both a bridge and a barrier to creativity in organisations. Recent social psychological experimental research (Slighte, de Dreu & Nijstad, 2011) on the relation between power...... and creativity suggests that when managers give people the opportunity to gain power and explicate that there is reason to be more creative, people will show a boost in creative behaviour. Moreover, this process works best in unstable power hierarchies, which implies that power is treated as a negotiable...... and floating source for empowering people in the organisation. We will explore and discuss here the potentials, challenges and pitfalls of power in relation to creativity in the life of organisations today. The aim is to demonstrate that power struggles may be utilised as constructive sources of creativity...
Study on Beam Shaping of High Power Diode Lasers%大功率半导体激光光源光束整形技术研究
Institute of Scientific and Technical Information of China (English)
彭航宇; 宁永强; 王立军; 顾媛媛; 单肖楠; 刘云; 郝明明; 朱洪波; 尹红贺; 田振华; 秦莉
2011-01-01
光束质量是半导体激光器应用的最大瓶颈,但是可以利用光束整形技术加以改善.随着半导体激光合束技术的发展,半导体激光光束质量的提高,由于其在效率方面的优势,大功率半导体激光技术得到迅速发展.采用连续输出60 W,转换效率达到57%的880 nm大功率半导体激光bar条,组成20层的半导体激光叠阵,输出功率达到1183 W,通过快慢轴准直及光束整形提高激光器的光束质量,最终实现1 kw功率输出,电一光转换效率超过45.8%,光束质量达到79.3 mm·mrad×81.2 mm·mrad.从而使半导体激光器可直接应用于熔覆、表面硬化等领域.%The major drawback of high power diode laser systems is their poor beam quality, which can be improved by beam shaping and beam combination. With the high wall-plug efficiency, high power laser diode developed rapidly. Base on bars rated to 60 W and 57％ conversion efficiency, vertically stacked arrays (twenty bars) of such configuration are demonstrated with rated to 1183 W. The beam quality of high-power high brightness 880 nm laser diode source is improved with beam shaping. Beam parameter product of 79.3 mm · mrad × 81.2 mm · mrad, electro-optical conversion efficiency of more than 45.8％ and continuous output power of 1 kW are demonstrated. This laser can be directly applied to cladding, surface hardening and other fields.
Yamin, Alicia Ely; Bazile, Junior; Knight, Lucia; Molla, Mitike; Maistrellis, Emily; Leaning, Jennifer
2015-06-01
Driven by the need to better understand the full and intergenerational toll of maternal mortality (MM), a mixed-methods study was conducted in four countries in sub-Saharan Africa to investigate the impacts of maternal death on families and children. The present analysis identifies gender as a fundamental driver not only of maternal, but also child health, through manifestations of gender inequity in household decision making, labor and caregiving, and social norms dictating the status of women. Focus group discussions were conducted with community members, and in depth qualitative interviews with key-informants and stakeholders, in Tanzania, Ethiopia, Malawi, and South Africa between April 2012 and October 2013. Findings highlight that socially constructed gender roles, which define mothers as caregivers and fathers as wage earners, and which limit women's agency regarding childcare decisions, among other things, create considerable gaps when it comes to meeting child nutrition, education, and health care needs following a maternal death. Additionally, our findings show that maternal deaths have differential effects on boy and girl children, and exacerbate specific risks for girl children, including early marriage, early pregnancy, and school drop-out. To combat both MM, and to mitigate impacts on children, investment in health services interventions should be complemented by broader interventions regarding social protection, as well as aimed at shifting social norms and opportunity structures regarding gendered divisions of labor and power at household, community, and society levels.
Energy Technology Data Exchange (ETDEWEB)
Neuhoff, K.; Boyd, R.; Grau, T. [Climate Policy Initiative, German Institute for Economic Research (DIW Berlin), Berlin (Germany); Hobbs, B.; Newbery, D. [Electricity Policy Research Group, University of Cambridge, Cambridge (United Kingdom); Borggrefe, F. [University of Cologne, Cologne (Germany); Barquin, J.; Echavarren, F. [Universidad Pontificia Comillas, Madrid (Spain); Bialek, J.; Dent, C. [Durham University, Durham (United Kingdom); Con Hirschhausen, C. [Technical University of Berlin, Berlin (Germany); Kunz, F.; Weigt, H. [Technical University of Dresden, Dresden (Germany); Nabe, C.; Papaefthymiou, G. [Ecofys Germany, Berlin (Germany); Weber, C. [Duisberg-Essen University, Duisburg-Essen (Germany)
2011-10-15
The core objective of the RE-Shaping project is to assist Member State governments in preparing for the implementation of Directive 2009/28/EC (on the promotion of the use of energy from renewable sources) and to guide a European policy for RES (renewable energy sources) in the mid- to long term. The past and present success of policies for renewable energies will be evaluated and recommendations derived to improve future RES support schemes. The core content of this collaborative research activity comprises: Developing a comprehensive policy background for RES support instruments; Providing the European Commission and Member States with scientifically based and statistically robust indicators to measure the success of currently implemented RES policies; Proposing innovative financing schemes for lower costs and better capital availability in RES financing; Initiation of National Policy Processes which attempt to stimulate debate and offer key stakeholders a meeting place to set and implement RES targets as well as options to improve the national policies fostering RES market penetration; Assessing options to coordinate or even gradually harmonize national RES policy approaches. In the EU, at least 200 gigawatts (GWs) of new and additional renewable electricity sources may be needed by 2020. The aim of this report is to analyse whether the current electricity market and system design is consistent with such an ambitious target. Using an international comparison, we identify opportunities to improve the power market design currently in place across EU countries so as to support the large scale integration of renewable energy sources.
Li, Ping
2016-09-09
A discontinuous Galerkin time-domain (DGTD) method analyzing signal/power integrity on multilayered power-ground parallel plate pairs is proposed. The excitation is realized by introducing wave ports on the antipads where electric/magnetic current sources are represented in terms of the eigenmodes of the antipads. Since closed-forms solutions do not exist for the eigenmodes of the arbitrarily shaped antipads, they have to be calculated using numerical schemes. Spatial orthogonality of the eigenmodes permits determination of each mode\\'s temporal expansion coefficient by integrating the product of the electric field and the mode over the wave port. The temporal mode coefficients are then Fourier transformed to accurately calculate the S-parameters corresponding to different modes. Additionally, to generalize the DGTD to manipulate dispersive media, the auxiliary differential equation method is employed. This is done by introducing a time-dependent polarization volume current as an auxiliary unknown and the constitutive relation between this current and the electric field as an auxiliary equation. Consequently, computationally expensive temporal convolution is avoided. Various numerical examples, which demonstrate the applicability, robustness, and accuracy of the proposed method, are presented.
Realization of Fractal Affine Transformation
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
This paper gives the definition of fractal affine transformation and presents a specific method for its realization and its cor responding mathematical equations which are essential in fractal image construction.
Affinity chromatography of phosphorylated proteins.
Tchaga, Grigoriy S
2008-01-01
This chapter covers the use of immobilized metal ion affinity chromatography (IMAC) for enrichment of phosphorylated proteins. Some requirements for successful enrichment of these types of proteins are discussed. An experimental protocol and a set of application data are included to enable the scientist to obtain high-yield results in a very short time with pre-packed phospho-specific metal ion affinity resin (PMAC).
Oriented angles in affine space
Directory of Open Access Journals (Sweden)
Włodzimierz Waliszewski
2004-05-01
Full Text Available The concept of a smooth oriented angle in an arbitrary affine space is introduced. This concept is based on a kinematics concept of a run. Also, a concept of an oriented angle in such a space is considered. Next, it is shown that the adequacy of these concepts holds if and only if the affine space, in question, is of dimension 2 or 1.
Institute of Scientific and Technical Information of China (English)
Deepak; PRASAD; Mohammed; Asid; ZULLAH; Mohammed; Rafiuddin; AHMED; Young-Ho; LEE
2010-01-01
There is an increasing interest in cross flow turbines(also known as Banki turbines) for small and low head applications because of their simple structure as well as low capital and maintenance costs.The present work aims at implementing the direct drive turbine(DDT) of cross flow type for wave power generation.A numerical wave tank was used to simulate the waves and after obtaining the desired wave properties;the augmentation channel plus the front guide nozzle and rear chamber were integrated to the numerical wave tank.The waves in the numerical wave tank were generated by a piston type wave maker which was located at the wave tank inlet.The inlet which was modeled as a plate wall moved sinusoidally with the general function x = asinω t.The augmentation channel consisted of a front nozzle,rear nozzle and an internal fluid region which represented the turbine housing.The front and rear nozzles were geometrically the same.Three different front guide nozzle configurations were studied:a standard guide nozzle which was originally attached to the augmentation channel and two other front guide nozzles of different geometries.The purpose of this study is to observe how the front guide nozzle shape influences the flow downstream,mainly in the augmenta-tion channel,water power and the first stage energy conversion.The analysis was performed using a commercial CFD code ANSYS-CFX.The results of the flow in the augmentation channel for the three front guide nozzles are presented in this paper.
Affine Contractions on the Plane
Celik, D.; Ozdemir, Y.; Ureyen, M.
2007-01-01
Contractions play a considerable role in the theory of fractals. However, it is not easy to find contractions which are not similitudes. In this study, it is shown by counter examples that an affine transformation of the plane carrying a given triangle onto another triangle may not be a contraction even if it contracts edges, heights or medians.…
Theoretical proton affinity and fluoride affinity of nerve agent VX.
Bera, Narayan C; Maeda, Satoshi; Morokuma, Keiji; Viggiano, Al A
2010-12-23
Proton affinity and fluoride affinity of nerve agent VX at all of its possible sites were calculated at the RI-MP2/cc-pVTZ//B3LYP/6-31G* and RI-MP2/aug-cc-pVTZ//B3LYP/6-31+G* levels, respectively. The protonation leads to various unique structures, with H(+) attached to oxygen, nitrogen, and sulfur atoms; among which the nitrogen site possesses the highest proton affinity of -ΔE ∼ 251 kcal/mol, suggesting that this is likely to be the major product. In addition some H(2), CH(4) dissociation as well as destruction channels have been found, among which the CH(4) + [Et-O-P(═O)(Me)-S-(CH(2))(2)-N(+)(iPr)═CHMe] product and the destruction product forming Et-O-P(═O)(Me)-SMe + CH(2)═N(+)(iPr)(2) are only 9 kcal/mol less stable than the most stable N-protonated product. For fluoridization, the S-P destruction channel to give Et-O-P(═O)(Me)(F) + [S-(CH(2))(2)-N-(iPr)(2)](-) is energetically the most favorable, with a fluoride affinity of -ΔE ∼ 44 kcal. Various F(-) ion-molecule complexes are also found, with the one having F(-) interacting with two hydrogen atoms in different alkyl groups to be only 9 kcal/mol higher than the above destruction product. These results suggest VX behaves quite differently from surrogate systems.
Electron affinity of chlorine dioxide
Energy Technology Data Exchange (ETDEWEB)
Babcock, L.M.; Pentecost, T.; Koppenol, W.H. (Louisiana State Univ., Baton Rouge (USA))
1989-12-14
The flowing afterglow technique was used to determine the electron affinity of chlorine dioxide. A value of 2.37 {plus minus} 0.10 eV was found by bracketing between the electron affinities of HS* and SF{sub 4} as a lower limit and that of NO{sub 2} as an upper limit. This value is in excellent agreement with 2.32 eV predicted from a simple thermodynamic cycle involving the reduction potential of the ClO{sub 2}/ClO{sub 2}{sup {minus}} couple and a Gibbs hydration energy identical with that of SO{sub 2}{sup {sm bullet}{minus}}.
Affine density in wavelet analysis
Kutyniok, Gitta
2007-01-01
In wavelet analysis, irregular wavelet frames have recently come to the forefront of current research due to questions concerning the robustness and stability of wavelet algorithms. A major difficulty in the study of these systems is the highly sensitive interplay between geometric properties of a sequence of time-scale indices and frame properties of the associated wavelet systems. This volume provides the first thorough and comprehensive treatment of irregular wavelet frames by introducing and employing a new notion of affine density as a highly effective tool for examining the geometry of sequences of time-scale indices. Many of the results are new and published for the first time. Topics include: qualitative and quantitative density conditions for existence of irregular wavelet frames, non-existence of irregular co-affine frames, the Nyquist phenomenon for wavelet systems, and approximation properties of irregular wavelet frames.
Automatic gesture analysis using constant affine velocity.
Cifuentes, Jenny; Boulanger, Pierre; Pham, Minh Tu; Moreau, Richard; Prieto, Flavio
2014-01-01
Hand human gesture recognition has been an important research topic widely studied around the world, as this field offers the ability to identify, recognize, and analyze human gestures in order to control devices or to interact with computer interfaces. In particular, in medical training, this approach is an important tool that can be used to obtain an objective evaluation of a procedure performance. In this paper, some obstetrical gestures, acquired by a forceps, were studied with the hypothesis that, as the scribbling and drawing movements, they obey the one-sixth power law, an empirical relationship which connects path curvature, torsion, and euclidean velocity. Our results show that obstetrical gestures have a constant affine velocity, which is different for each type of gesture and based on this idea this quantity is proposed as an appropriate classification feature in the hand human gesture recognition field.
Self-affinity and nonextensivity of sunspots
Energy Technology Data Exchange (ETDEWEB)
Moret, M.A., E-mail: mamoret@gmail.com [Programa de Modelagem Computacional, SENAI, Cimatec, Av. Orlando Gomes, 1845, Piatã, 41650-010 Salvador, Bahia (Brazil); UNEB, Rua Silveira Martins, 2555, Cabula, 41150-000 Salvador, Bahia (Brazil)
2014-01-24
In this paper we study the time series of sunspots by using two different approaches, analyzing its self-affine behavior and studying its distribution. The long-range correlation exponent α has been calculated via Detrended Fluctuation Analysis and the power law vanishes to values greater than 11 years. On the other hand, the distribution of the sunspots obeys a q-exponential decay that suggests a non-extensive behavior. This observed characteristic seems to take an alternative interpretation of the sunspots dynamics. The present findings suggest us to propose a dynamic model of sunspots formation based on a nonlinear Fokker–Planck equation. Therefore its dynamic process follows the generalized thermostatistical formalism.
Lectin affinity chromatography of glycolipids
Energy Technology Data Exchange (ETDEWEB)
Torres, B.V.; Smith, D.F.
1987-05-01
Since glycolipids (GLs) are either insoluble or form mixed micelles in water, lectin affinity chromatography in aqueous systems has not been applied to their separation. They have overcome this problem by using tetrahydrofuran (THF) in the mobile phase during chromatography. Affinity columns prepared with the GalNAc-specific Helix pomatia agglutinin (HPA) and equilibrated in THF specifically bind the (/sup 3/H)oligosaccharide derived from Forssman GL indicating that the immobilized HPA retained its carbohydrate-binding specificity in this solvent. Intact Forssman GL was bound by the HPA-column equilibrated in THF and was specifically eluted with 0.1 mg/ml GalNAc in THF. Purification of the Forssman GL was achieved when a crude lipid extract of sheep erythrocyte membranes was applied to the HPA-column in THF. Non-specifically bound GLs were eluted from the column using a step gradient of aqueous buffer in THF, while the addition of GalNAc was required to elute the specifically bound GLs. Using this procedure the A-active GLs were purified from a crude lipid extract of type A human erythrocytes in a single chromatographic step. The use of solvents that maintain carbohydrate-binding specificity and lipid solubility will permit the application of affinity chromatography on immobilized carbohydrate-binding proteins to intact GLs.
The Quasi—affine Maps and Fractals
Institute of Scientific and Technical Information of China (English)
LunhaiLONG; GangCHEN
1997-01-01
In this paper,we discuss the discretization of the affine maps in R2,that is ,we consider a class of maps in Z2,which are induced by affine maps and called the quasi-affine maps.We investigate the properties and the dynamical behaviour of such maps,and give a sort of construction of complicated fractals by using quasi-affine maps.
Affine connections on involutive G-structures
Merkulov, Sergey A.
1995-01-01
This paper is a review of the twistor theory of irreducible G-structures and affine connections. Long ago, Berger presented a very restricted list of possible irreducibly acting holonomies of torsion-free affine connections. His list was complete in the part of metric connections, while the situation with holonomies of non-metric torsion-free affine connections was and remains rather unclear. One of the results discussed in this review asserts that any torsion-free holomorphic affine connecti...
O'Connell, Emily
2009-01-01
This article describes a lesson on Schapiro Shapes. Schapiro Shapes is based on the art of Miriam Schapiro, who created a number of works of figures in action. Using the basic concepts of this project, students learn to create their own figures and styles. (Contains 1 online resource.)
Baumbick, Robert J. (Inventor)
2002-01-01
The present invention discloses and teaches a unique, remote optically controlled micro actuator particularly suitable for aerospace vehicle applications wherein hot gas, or in the alternative optical energy, is employed as the medium by which shape memory alloy elements are activated. In gas turbine powered aircraft the source of the hot gas may be the turbine engine compressor or turbine sections.
Topological conjugacy classes of affine maps
2008-01-01
A map $f: \\ff^n \\to \\ff^n$ over a field $\\ff$ is called affine if it is of the form $f(x)=Ax+b$, where the matrix $A \\in \\ff^{n\\times n}$ is called the linear part of affine map and $b \\in \\ff^n$. The affine maps over $\\ff=\\rr$ or $\\cc$ are investigated. We prove that affine maps having fixed points are topologically conjugate if and only if their linear parts are topologically conjugate. If affine maps have no fixed points and $n=1$ or 2, then they are topologically conjugate if and only if ...
Using Affinity Diagrams to Evaluate Interactive Prototypes
DEFF Research Database (Denmark)
Lucero, Andrés
2015-01-01
Affinity diagramming is a technique used to externalize, make sense of, and organize large amounts of unstructured, far-ranging, and seemingly dissimilar qualitative data. HCI and interaction design practitioners have adopted and used affinity diagrams for different purposes. This paper discusses...... our particular use of affinity diagramming in prototype evaluations. We reflect on a decade’s experience using affinity diagramming across a number of projects, both in industry and academia. Our affinity diagramming process in interaction design has been tailored and consists of four stages: creating...
Craniomandibular morphology and phylogenetic affinities of panthera atrox
DEFF Research Database (Denmark)
Christiansen, Per; Harris, J.M.
2009-01-01
The great North American Pleistocene pantherine felid Panthera atrox has had a turbulent phylogenetic history, and has been claimed to show affinities to both the jaguar and the tiger; currently, it is most often regarded as a subspecies of the extant lion. The cranial, mandibular, and dental...... morphology of Panthera atrox was compared with those of extant lions, jaguars, and tigers using bivariate, multivariate, and shape analyses. Results indicate that the skull of Panthera atrox shows lion affinities, but also deviates from lions in numerous aspects. Mandibular morphology is more similar...... to jaguars and tigers and, as with cranial morphology, the mandible shows a number of traits not present among extant pantherines. Multivariate analyses grouped Panthera atrox separately from other pantherines. Panthera atrox was no lion, and cannot be assigned to any of the extant pantherines...
Affinity Purification of Protein Complexes Using TAP Tags
Gerace, Erica; Moazed, Danesh
2016-01-01
This protocol is used for the isolation and analysis of protein complexes using the tandem affinity purification (TAP) tag system. The protocol describes the purification of a protein fused to a TAP tag comprised of two protein A domains and the calmodulin binding peptide separated by a TEV cleavage site. This is a powerful technique for rapid purification of protein complexes and the analysis of their stoichiometric composition, posttranslational modifications, structure, and functional activities. PMID:26096502
Bulbeck, David
2013-01-01
Genetic research into Southeast Asia's "negritos" has revealed their deep-rooted ancestry, with time depth comparable to that of Southwest Pacific populations. This finding is often interpreted as evidence that negritos, in contrast to other Southeast Asians, can trace much of their ancestry directly back to the early dispersal of Homo sapiens in the order of 70 kya from Africa to Pleistocene New Guinea and Australia. One view on negritos is to lump them and Southwest Pacific peoples into an "Australoid" race whose geographic distribution had included Southeast Asia prior to the Neolithic incursion of "Mongoloid" farmers. Studies into Semang osteology have revealed some hints of Southwest Pacific affinities in cranial shape, dental morphology, and dental metrical "shape." On the other hand, the Andamanese have been shown to resemble Africans in their craniometrics and South Asians in their dental morphology, while Philippine negritos resemble Mongoloid Southeast Asians in these respects and also in their dental metrics. This study expands the scope of negrito cranial comparisons by including Melayu Malays and additional coverage of South Asians. It highlights the distinction between the Mongoloid-like Philippine negritos and the Andamanese and Semang (and Senoi of Malaya) with their non-Mongoloid associations. It proposes that the early/mid-Holocene dispersal of the B4a1a mitochondrial DNA clade across Borneo, the Philippines, and Taiwan may be important for understanding the distinction between Philippine and other negritos.
Indian Academy of Sciences (India)
Xu Wei; Li Yan
2014-09-01
The particles energy distribution is derived directly from the () line shape, which is measured by two sets of OMA. The dissociative excitation of molecular is dominating when the local electron temperature is > 10 eV. The line shape is also simulated by the Monte–Carlo method, the molecular dissociation contributes to 57% neutral atoms and 53% emission intensity in front of the limiter, and 85% neutral atoms and 82% emission intensity in front of the wall. The processes of atoms and molecules influence on the energy balance is discussed in SOL, the power loss from molecular dissociation is 6 × 104 kW at SOL.
Ordinary differential equations in affine geometry
Directory of Open Access Journals (Sweden)
Salvador Gigena
1996-05-01
Full Text Available The method of qualitative analysis is used, as applied to a class of fourth order, nonlinear ordinary differential equations, in order to classify, both locally and globally, two classes of hypersurfaces of decomposable type in affine geometry: those with constant unimodular affine mean curvature L , and those with constant Riemannian scalar curvature R. This allows to provide a large number of new examples of hypersurfaces in affine geometry.
Ordinary differential equations in affine geometry
Salvador Gigena
1996-01-01
The method of qualitative analysis is used, as applied to a class of fourth order, nonlinear ordinary differential equations, in order to classify, both locally and globally, two classes of hypersurfaces of decomposable type in affine geometry: those with constant unimodular affine mean curvature L , and those with constant Riemannian scalar curvature R. This allows to provide a large number of new examples of hypersurfaces in affine geometry.
Multipole solutions in metric-affine gravity
Socorro, J; Macías, A; Mielke, E W; Socorro, José; Lämmerzahl, Claus; Macías, Alfredo; Mielke, Eckehard W.
1998-01-01
Above Planck energies, the spacetime might become non--Riemannian, as it is known fron string theory and inflation. Then geometries arise in which nonmetricity and torsion appear as field strengths, side by side with curvature. By gauging the affine group, a metric affine gauge theory emerges as dynamical framework. Here, by using the harmonic map ansatz, a new class of multipole like solutions in the metric affine gravity theory (MAG) is obtained.
Kim, Youngdeuk
2011-04-15
The quantitative correlations between workpiece volume and melt pool geometry, as well as the flow and thermal features of the melt pool are established. Thermocapillary convections in melt pool with a deformable free surface are investigated with respect to surface shape and laser intensity. When the contact angle between the tangent to the top surface and the vertical wall at the hot center is acute, the free surface flattens, compared with that of the initial free surface. Otherwise, the free surface forms a bowl-like shape with a deep crater and a low peripheral rim when the contact angle at the hot center is obtuse. Increasing the workpiece volume at a fixed laser intensity and a negative radial height gradient cause linear decreases in the geometric size and magnitude of flow and temperature of the melt pool. Conversely, linear increases are observed with a positive radial height gradient. © 2011 American Institute of Chemical Engineers (AIChE).
Several Affinity Tags Commonly Used in Chromatographic Purification
Directory of Open Access Journals (Sweden)
Xinyu Zhao
2013-01-01
Full Text Available Affinity tags have become powerful tools from basic biological research to structural and functional proteomics. They were widely used to facilitate the purification and detection of proteins of interest, as well as the separation of protein complexes. Here, we mainly discuss the benefits and drawbacks of several affinity or epitope tags frequently used, including hexahistidine tag, FLAG tag, Strep II tag, streptavidin-binding peptide (SBP tag, calmodulin-binding peptide (CBP, glutathione S-transferase (GST, maltose-binding protein (MBP, S-tag, HA tag, and c-Myc tag. In some cases, a large-size affinity tag, such as GST or MBP, can significantly impact on the structure and biological activity of the fusion partner protein. So it is usually necessary to excise the tag by protease. The most commonly used endopeptidases are enterokinase, factor Xa, thrombin, tobacco etch virus, and human rhinovirus 3C protease. The proteolysis features of these proteases are described in order to provide a general guidance on the proteolytic removal of the affinity tags.
Hartman, Jacob M; Chakrabarty, Deepto; Kaplan, David L; Markwardt, Craig B; Morgan, Edward H; Ray, Paul S; van der Klis, Michiel; Wijnands, Rudy
2007-01-01
We present a 7 yr timing study of the 2.5 ms X-ray pulsar SAX J1808.4-3658, an X-ray transient with a recurrence time of ~2 yr, using data from the Rossi X-ray Timing Explorer covering 4 transient outbursts (1998-2005). We verify that the 401 Hz pulsation traces the spin frequency fundamental and not a harmonic. Substantial pulse shape variability, both stochastic and systematic, was observed during each outburst. Analysis of the systematic pulse shape changes suggests that, as an outburst dims, the X-ray "hot spot" on the pulsar surface drifts longitudinally and a second hot spot may appear. The overall pulse shape variability limits the ability to measure spin frequency evolution within a given X-ray outburst (and calls previous nudot measurements of this source into question), with typical upper limits of |nudot| < 2.5x10^{-14} Hz/s (2 sigma). However, combining data from all the outbursts shows with high (6 sigma) significance that the pulsar is undergoing long-term spin down at a rate nudot = (-5.6+/-...
Measurement of the electron affinity of lanthanum
Energy Technology Data Exchange (ETDEWEB)
Covington, A.M.; Calabrese, D.; Thompson, J.S. [Department of Physics and Chemical Physics Programme, University of Nevada, Reno, NV 89557-0058 (United States); Kvale, T.J. [Department of Physics and Astronomy, University of Toledo, OH 43606-3390 (United States)
1998-10-28
The electron affinity of lanthanum has been measured using laser photoelectron energy spectroscopy. This is the first electron affinity measurement for lanthanum and one of the first measurements of an electron affinity of a rare-earth series element. The electron affinity of lanthanum was measured to be 0.47{+-}0.02 eV. At least one bound excited state of La{sup -} was also observed in the photoelectron spectra, and the binding energy relative to the ground state of lanthanum was measured as 0.17{+-}0.02 eV. The present experimental measurements are compared to a recent calculation. (author). Letter-to-the-editor.
A Novel Vertex Affinity for Community Detection
Energy Technology Data Exchange (ETDEWEB)
Yoo, Andy [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sanders, Geoffrey [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Henson, Van [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vassilevski, Panayot [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2015-10-05
We propose a novel vertex affinity measure in this paper. The new vertex affinity quantifies the proximity between two vertices in terms of their clustering strength and is ideal for such graph analytics applications as community detection. We also developed a framework that combines simple graph searches and resistance circuit formulas to compute the vertex affinity efficiently. We study the properties of the new affinity measure empirically in comparison to those of other popular vertex proximity metrics. Our results show that the existing metrics are ill-suited for community detection due to their lack of fundamental properties that are essential for correctly capturing inter- and intra-cluster vertex proximity.
Affine connections, midpoint formation, and point reflection
DEFF Research Database (Denmark)
Kock, Anders
2011-01-01
We describe some differential-geometric structures in combinatorial terms: namely affine connections and their torsion and curvature, and we show that torsion free affine connections may equivalently be presented in terms of some simpler combinatorial structure: midpoint formation, and point refl...... reflection (geodesic symmetry). The method employed is that of synthetic differential geometry, which is briefly explained.......We describe some differential-geometric structures in combinatorial terms: namely affine connections and their torsion and curvature, and we show that torsion free affine connections may equivalently be presented in terms of some simpler combinatorial structure: midpoint formation, and point...
Institute of Scientific and Technical Information of China (English)
亚玲
2007-01-01
<正>Teenagers have been of a new shape these days. They are about 20 pounds heavier than teenagers were 60 years ago. They are about four inches taller, too. These facts come from J. M. Tanner, a professor in England.
Structure of classical affine and classical affine fractional W-algebras
Energy Technology Data Exchange (ETDEWEB)
Suh, Uhi Rinn, E-mail: uhrisu1@math.snu.ac.kr [Department of Mathematical Sciences, Seoul National University, GwanAkRo 1, Gwanak-Gu, Seoul 151-747 (Korea, Republic of)
2015-01-15
We introduce a classical BRST complex (See Definition 3.2.) and show that one can construct a classical affine W-algebra via the complex. This definition clarifies that classical affine W-algebras can be considered as quasi-classical limits of quantum affine W-algebras. We also give a definition of a classical affine fractional W-algebra as a Poisson vertex algebra. As in the classical affine case, a classical affine fractional W-algebra has two compatible λ-brackets and is isomorphic to an algebra of differential polynomials as a differential algebra. When a classical affine fractional W-algebra is associated to a minimal nilpotent, we describe explicit forms of free generators and compute λ-brackets between them. Provided some assumptions on a classical affine fractional W-algebra, we find an infinite sequence of integrable systems related to the algebra, using the generalized Drinfel’d and Sokolov reduction.
Global affine differential geometry of hypersurfaces
Li, An-Min; Zhao, Guosong; Hu, Zejun
2015-01-01
This book draws a colorful and widespread picture of global affine hypersurface theory up to the most recent state. Moreover, the recent development revealed that affine differential geometry- as differential geometry in general- has an exciting intersection area with other fields of interest, like partial differential equations, global analysis, convex geometry and Riemann surfaces.
Dyes with high affinity for polylactide
Institute of Scientific and Technical Information of China (English)
Liang He; Shu Fen Zhang; Bing Tao Tang; Li Li Wang; Jin Zong Yang
2007-01-01
Attempts were made to develop dyes with high affinity for polylactide as an alternative to the existent commercial disperse dyes.The dyes synthesized according to the affinity concept of dye to polylactide exhibited excellent dyeing properties on polylactide compared with the commercial disperse dyes.
Phosphopeptide enrichment by immobilized metal affinity chromatography
DEFF Research Database (Denmark)
Thingholm, Tine E.; Larsen, Martin R.
2016-01-01
Immobilized metal affinity chromatography (IMAC) has been the method of choice for phosphopeptide enrichment prior to mass spectrometric analysis for many years and it is still used extensively in many laboratories. Using the affinity of negatively charged phosphate groups towards positively...
Institute of Scientific and Technical Information of China (English)
Lifeng XI
2008-01-01
In this paper,it is proved that any self-affine set satisfying the strong separation condition is uniformly porous.The author constructs a self-affine set which is not porous,although the open set condition holds.Besides,the author also gives a C1 iterated function system such that its invariant set is not porous.
On affine non-negative matrix factorization
DEFF Research Database (Denmark)
Laurberg, Hans; Hansen, Lars Kai
2007-01-01
We generalize the non-negative matrix factorization (NMF) generative model to incorporate an explicit offset. Multiplicative estimation algorithms are provided for the resulting sparse affine NMF model. We show that the affine model has improved uniqueness properties and leads to more accurate...
Affine processes on positive semidefinite matrices
Cuchiero, Christa; Mayerhofer, Eberhard; Teichmann, Josef
2009-01-01
This paper provides the mathematical foundation for stochastically continuous affine processes on the cone of positive semidefinite symmetric matrices. These matrix-valued affine processes have arisen from a large and growing range of useful applications in finance, including multi-asset option pricing with stochastic volatility and correlation structures, and fixed-income models with stochastically correlated risk factors and default intensities.
Reflectable bases for affine reflection systems
Azam, Saeid; Yousofzadeh, Malihe
2011-01-01
The notion of a "root base" together with its geometry plays a crucial role in the theory of finite and affine Lie theory. However, it is known that such a notion does not exist for the recent generalizations of finite and affine root systems such as extended affine root systems and affine reflection systems. As an alternative, we introduce the notion of a "reflectable base", a minimal subset $\\Pi$ of roots such that the non-isotropic part of the root system can be recovered by reflecting roots of $\\Pi$ relative to the hyperplanes determined by $\\Pi$. We give a full characterization of reflectable bases for tame irreducible affine reflection systems of reduced types, excluding types $E_{6,7,8}$. As a byproduct of our results, we show that if the root system under consideration is locally finite then any reflectable base is an integral base.
Improving image segmentation by learning region affinities
Energy Technology Data Exchange (ETDEWEB)
Prasad, Lakshman [Los Alamos National Laboratory; Yang, Xingwei [TEMPLE UNIV.; Latecki, Longin J [TEMPLE UNIV.
2010-11-03
We utilize the context information of other regions in hierarchical image segmentation to learn new regions affinities. It is well known that a single choice of quantization of an image space is highly unlikely to be a common optimal quantization level for all categories. Each level of quantization has its own benefits. Therefore, we utilize the hierarchical information among different quantizations as well as spatial proximity of their regions. The proposed affinity learning takes into account higher order relations among image regions, both local and long range relations, making it robust to instabilities and errors of the original, pairwise region affinities. Once the learnt affinities are obtained, we use a standard image segmentation algorithm to get the final segmentation. Moreover, the learnt affinities can be naturally unutilized in interactive segmentation. Experimental results on Berkeley Segmentation Dataset and MSRC Object Recognition Dataset are comparable and in some aspects better than the state-of-art methods.
DEFF Research Database (Denmark)
Østergaard, Jesper; Jensen, Henrik; Holm, Rene
2012-01-01
an influence on the ionic strength of the background electrolyte when the cyclodextrin is used in capillary electrophoresis. Mobility-shift affinity capillary methods for investigation of the complexation of taurocholate and taurochenodeoxycholate with the negatively charged cyclodextrin derivative applying...... constant power and ionic strength conditions as well as constant voltage and varying ionic strength were investigated. A new approach for the correction of background electrolyte ionic strength was developed. Mobility-shift affinity capillary electrophoresis experiments obtained at constant voltage...
Affinity Spaces, Apprenticeships, and Agency: Exploring Blogging Engagements in Family Spaces
Lewis, Tisha Y.
2014-01-01
This empirical study examines the virtual exchanges between an African American mother and son's engagement in a blog. Using literacy as social practices as a framework, this study describes how blogging was developed and used to create affinity spaces, encouraged apprenticeship models, and shaped agentic roles within their family. Attention…
Food and value motivation: Linking consumer affinities to different types of food products
Boer, de J.; Schosler, H.
2016-01-01
This study uses the consumer affinity concept to examine the multiple motives that may shape consumers’ relationships with food. The concept was applied in a study on four broad product types in the Netherlands, which cover a wide range of the market and may each appeal to consumers with different a
Non-Zenoness of piecewise affine dynamical systems and affine complementarity systems with inputs
Institute of Scientific and Technical Information of China (English)
Le Quang THUAN
2014-01-01
In the context of continuous piecewise affine dynamical systems and affine complementarity systems with inputs, we study the existence of Zeno behavior, i.e., infinite number of mode transitions in a finite-length time interval, in this paper. The main result reveals that continuous piecewise affine dynamical systems with piecewise real-analytic inputs do not exhibit Zeno behavior. Applied the achieved result to affine complementarity systems with inputs, we also obtained a similar conclusion. A direct benefit of the main result is that one can apply smooth ordinary differential equations theory in a local manner for the analysis of continuous piecewise affine dynamical systems with inputs.
Directory of Open Access Journals (Sweden)
Morizane Toshimitsu
2015-12-01
Full Text Available It has been proposed that a novel maglev transport system uses both of the attractive force and thrust force of the Linear Induction Motor (LIM. In our proposal, these two forces will be controlled by two different frequency components. One of the frequency components is synchronous with the motor speed (fm. Another frequency component is drive frequency (fd. Our proposed system enables the independent and simultaneous control of the attractive and thrust force of LIM. Each value of the attractive and the thrust force generated by fm and fd must be identified in order to design that LIM control system. For these purpose, a disc-shaped LIM has been developed as an experimental equipment. The force profiles, especially around zero slip, have been analyzed under experimental conditions.
The Cutting Edge of Affinity Electrophoresis Technology
Directory of Open Access Journals (Sweden)
Eiji Kinoshita
2015-03-01
Full Text Available Affinity electrophoresis is an important technique that is widely used to separate and analyze biomolecules in the fields of biology and medicine. Both quantitative and qualitative information can be gained through affinity electrophoresis. Affinity electrophoresis can be applied through a variety of strategies, such as mobility shift electrophoresis, charge shift electrophoresis or capillary affinity electrophoresis. These strategies are based on changes in the electrophoretic patterns of biological macromolecules that result from interactions or complex-formation processes that induce changes in the size or total charge of the molecules. Nucleic acid fragments can be characterized through their affinity to other molecules, for example transcriptional factor proteins. Hydrophobic membrane proteins can be identified by means of a shift in the mobility induced by a charged detergent. The various strategies have also been used in the estimation of association/disassociation constants. Some of these strategies have similarities to affinity chromatography, in that they use a probe or ligand immobilized on a supported matrix for electrophoresis. Such methods have recently contributed to profiling of major posttranslational modifications of proteins, such as glycosylation or phosphorylation. Here, we describe advances in analytical techniques involving affinity electrophoresis that have appeared during the last five years.
The Cutting Edge of Affinity Electrophoresis Technology
Kinoshita, Eiji; Kinoshita-Kikuta, Emiko; Koike, Tohru
2015-01-01
Affinity electrophoresis is an important technique that is widely used to separate and analyze biomolecules in the fields of biology and medicine. Both quantitative and qualitative information can be gained through affinity electrophoresis. Affinity electrophoresis can be applied through a variety of strategies, such as mobility shift electrophoresis, charge shift electrophoresis or capillary affinity electrophoresis. These strategies are based on changes in the electrophoretic patterns of biological macromolecules that result from interactions or complex-formation processes that induce changes in the size or total charge of the molecules. Nucleic acid fragments can be characterized through their affinity to other molecules, for example transcriptional factor proteins. Hydrophobic membrane proteins can be identified by means of a shift in the mobility induced by a charged detergent. The various strategies have also been used in the estimation of association/disassociation constants. Some of these strategies have similarities to affinity chromatography, in that they use a probe or ligand immobilized on a supported matrix for electrophoresis. Such methods have recently contributed to profiling of major posttranslational modifications of proteins, such as glycosylation or phosphorylation. Here, we describe advances in analytical techniques involving affinity electrophoresis that have appeared during the last five years.
Corner Transfer Matrices and Quantum Affine Algebras
Foda, O E; Foda, Omar; Miwa, Tetsuji
1992-01-01
Let H be the corner-transfer-matrix Hamiltonian for the six-vertex model in the anti-ferroelectric regime. It acts on the infinite tensor product W = V . V . V ....., where is the 2-dimensional irreducible representation of the quantum affine sl(2). We observe that H is the derivation of quantum affine sl(2), and conjecture that the eigenvectors of H form the level-1 vacuum representation of quantum affine sl(2). We report on checks in support of our conjecture.
Affinization of category O for quantum groups
Young, C A S
2012-01-01
Let g be a simple Lie algebra. We consider the category O-hat of those modules over the affine quantum group Uq(g-hat) whose Uq(g)-weights have finite multiplicity and lie in a finite union of cones generated by negative roots. We show that many properties of the category of the finite-dimensional representations naturally extend to the category O-hat. In particular, we develop the theory of q-characters and define the minimal affinizations of parabolic Verma modules. In types ABCFG we classify these minimal affinizations and conjecture a Weyl denominator type formula for their characters.
Carballo, R; Benn, C R; Sánchez, S F; Vigotti, M
1999-01-01
UBVR photometry of a sample of B3-VLA radio quasars, about 80 per cent complete, is used to analyse their spectral energy distribution (SED). The SEDs are generally well fitted with power-laws, with an average slope alpha=-0.39 (S_nu propto nu^alpha). Two quasars appear clearly differenciated, exhibiting redder colours that the rest, and they have redshifts z=0.50 and 1.12. Broad-band composite SEDs in the range 1300-4500 AA were obtained from the remaining quasars and they show the CIV1549 line and a break at around 3000 A, where the SED changes from alpha_blue=0.11+-0.16 at lambda>3000 A to alpha_UV=-0.66+-0.15 at lambda1.2 alpha_UV is more flat, -0.48+-0.12. A similar trend is found between alpha_UV and luminosity at 2400 A, L_2400, with luminous quasars exhibiting a bluer spectrum. In addition, an intrinsic correlation is found between L_2400 and radio power at 408 MHz. The correlations alpha_UV-z, alpha_UV-L_2400 and L_2400-z are consistent with accretion disc models with approximately constant black hol...
Emonts, B H C; Stroe, A; Pentericci, L; Villar-Martin, M; Norris, R P; Miley, G; De Breuck, C; van Moorsel, G A; Lehnert, M D; Carilli, C L; Rottgering, H J A; Seymour, N; Sadler, E M; Ekers, R D; Drouart, G; Feain, I; Colina, L; Stevens, J; Holt, J
2015-01-01
In the low-redshift Universe, the most powerful radio sources are often associated with gas-rich galaxy mergers or interactions. We here present evidence for an advanced, gas-rich (`wet') merger associated with a powerful radio galaxy at a redshift of z~2. This radio galaxy, MRC 0152-209, is the most infrared-luminous high-redshift radio galaxy known in the southern hemisphere. Using the Australia Telescope Compact Array, we obtained high-resolution CO(1-0) data of cold molecular gas, which we complement with HST/WFPC2 imaging and WHT long-slit spectroscopy. We find that, while roughly M(H2) ~ 2 x 10$^{10}$ M$_{\\odot}$ of molecular gas coincides with the central host galaxy, another M(H2) ~ 3 x 10$^{10}$ M$_{\\odot}$ is spread across a total extent of ~60 kpc. Most of this widespread CO(1-0) appears to follow prominent tidal features visible in the rest-frame near-UV HST/WFPC2 imaging. Ly$\\alpha$ emission shows an excess over HeII, but a deficiency over L(IR), which is likely the result of photo-ionisation by ...
Institute of Scientific and Technical Information of China (English)
吴忠强; 庄述燕; 韩延光
2013-01-01
针对风速多变及外界干扰情况下风电系统出现的风能利用率低、鲁棒性差及安全可靠性差等问题,提出了一种基于能量成形的直驱永磁风电系统最大风能捕获算法.该算法采用能量成形及端口受控哈密顿(PCH)系统方法,从能量平衡的角度,建立永磁发电机(PMSG) PCH系统的非线性模型,设计了PCH系统反馈控制器.通过基于PCH系统控制器和H∞控制器的叠加反馈,设计出能跟踪最佳转矩且具有扰动抑制的PCH系统H∞控制器.实验结果表明,该控制策略实现了风电系统的变速恒频运行、最大风能利用,验证了理论模型和控制策略的正确性、可行性.%Aiming at the problems of wind power system under variable wind speed and external disturbances, such as low wind energy utilization, poor robustness, low security and reliability, an algorithm is proposed based on energy shaping control method for direct-drive permanent-magnet wind power system to capture maximum wind power. The algorithm adopts energy shaping method and port-controlled Hamiltonian (PCH) system theory;and the PCH nonlinear model of permanent magnet synchronous generator (PMSG) is established from the energy-balancing point of view. The PCH feedback controller was designed. With the superposition feedback of PCH feedback controller and H∞ controller,a PCH system H∞ controller was designed to track optimal torque and suppress disturbance. The test result shows that this control strategy realizes variable speed constant frequency operation and maximum wind power utilization of wind power system,which verifies the validity and feasibility of theoretical model and control strategy.
Electrochemical Affinity Biosensors in Food Safety
Directory of Open Access Journals (Sweden)
Susana Campuzano
2017-02-01
Full Text Available Safety and quality are key issues of today’s food industry. Since the food chain is becoming more and more complex, powerful analytical methods are required to verify the performance of food safety and quality systems. Indeed, such methods require high sensitivity, selectivity, ability for rapid implementation and capability of automatic screening. Electroanalytical chemistry has, for decades, played a relevant role in food safety and quality assessment, taking more and more significance over time in the solution of analytical problems. At present, the implementation of electrochemical methods in the food is evident. This is in a large part due to the relevant results obtained by combining the attractive advantages of electrochemical transduction strategies (in terms of relatively simple hardware, versatility, interface with automatic logging and feasibility of application outside the laboratory environment with those from biosensors technology. Important examples of enzyme electrochemical biosensors are those dedicated to the determination of glucose, alcohol or cholesterol are important examples. In addition, other types of different electrochemical biosensing approaches have emerged strongly in the last years. Among these, the strategies involving affinity interactions have been shown to possess a large number of applications. Therefore, electrochemical immunosensors and DNA-based biosensors have been widely used to determine major and minor components in foodstuffs, providing sufficient data to evaluate food freshness, the quality of raw materials, or the origin of samples, as well as to determine a variety of compounds at trace levels related to food safety such as micotoxins, allergens, drugs residues or pathogen microorganisms. This review discusses some critical examples of the latest advances in this area, pointing out relevant methodologies related to the measurement techniques, including the use of nanostructured electrodes and
DEFF Research Database (Denmark)
Vorum, H; Pedersen, A O; Honoré, B
1992-01-01
of two albumin components about 40% of the albumin having high affinity and about 60% having low affinity. By affinity chromatography we succeeded in purifying the low-affinity component from the mixture. The high-affinity component, however, could not be isolated. We further analyzed the fatty acid...
Scaling laws in phytoplankton nutrient uptake affinity
DEFF Research Database (Denmark)
Lindemann, Christian; Fiksen, Øyvind; Andersen, Ken Haste
2016-01-01
Nutrient uptake affinity affects the competitive ability of microbial organisms at low nutrient concentrations. From the theory of diffusion limitation it follows that uptake affinity scales linearly with the cell radius. This is in conflict with some observations suggesting that uptake affinity...... scales to a quantity that is closer to the square of the radius, i.e. to cell surface area. We show that this apparent conflict can be resolved by nutrient uptake theory. Pure diffusion limitation assumes that the cell is a perfect sink which means that it is able to absorb all encountered nutrients...... to volume ratio. We show that there are two reasons for this. First, because the small cells need a higher transporter density in order to maximize their affinity, and second because the relative cost of a transporter is higher for a small than for a large cell. We suggest that this might explain why...
Protein purification using PDZ affinity chromatography.
Walkup, Ward G; Kennedy, Mary B
2015-04-01
PDZ domains function in nature as protein-binding domains within scaffold and membrane-associated proteins. They comprise approximately 90 residues and undergo specific, high-affinity interactions with complementary C-terminal peptide sequences, other PDZ domains, and/or phospholipids. We have previously shown that the specific, strong interactions of PDZ domains with their ligands make them well suited for use in affinity chromatography. This unit provides protocols for the PDZ affinity chromatography procedure that are applicable for the purification of proteins that contain PDZ domains or PDZ domain-binding ligands, either naturally or introduced by genetic engineering. We detail the preparation of affinity resins composed of PDZ domains or PDZ domain peptide ligands coupled to solid supports. These resins can be used to purify proteins containing endogenous or genetically introduced PDZ domains or ligands, eluting the proteins with free PDZ domain peptide ligands.
Niimura, Nobuo; Kikuchi, Kenji; Tuyen, Ninh Duc; Komatsuzaki, Masakazu; Motohashi, Yoshinobu
2015-01-01
We conducted an elution experiment with contaminated soils using various aqueous reagent solutions and autoradiography measurements of contaminated bamboo shoots and shiitake mushrooms to determine the physical and chemical characteristics of radioactive Cs from the Fukushima Daiichi Nuclear Power Plant accident. Based on our study results and data in the literature, we conclude that the active Cs emitted by the accident fell to the ground as granular non-ionic materials. Therefore, they were not adsorbed or trapped by minerals in the soil, but instead physically adhere to the rough surfaces of the soil mineral particles. Granular Cs* can be transferred among media, such as soils and plants. The physical properties and dynamic behavior of the granular Cs* is expected to be helpful in considering methods for decontamination of soil, litter, and other media.
APPROXIMATE OUTPUT REGULATION FOR AFFINE NONLINEAR SYSTEMS
Institute of Scientific and Technical Information of China (English)
Yali DONG; Daizhan CHENG; Huashu QIN
2003-01-01
Output regulation for affine nonlinear systems driven by an exogenous signal is investigated in this paper. In the absence of the standard exosystem hypothesis, we assume availability of the instantaneous values of the exogenous signal and its first time-derivative for use in the control law.For affine nonlinear systems, the necessary and sufficient conditions of the solvability of approximate output regulation problem are obtained. The precise form of the control law is presented under some suitable assumptions.
Applications of new affine invariant for polytopes
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
To study the Schneider's projection problem,Lutwak,Yang and Zhang recently introduced a new .affine invariant functional U(P) for convex polytopes in Rn.In the paper,we obtain the analytic expression of the affine-invariant U(P) defined on a specific subclass of origin-symmetric convex polytopes in Rn and give an application of U(P) to the Lp-Minkowski problem.
Fan affinity laws from a collision model
Bhattacharjee, Shayak
2012-01-01
The performance of a fan is usually estimated from hydrodynamical considerations. The calculations are long and involved and the results are expressed in terms of three affinity laws. In this work we use kinetic theory to attack this problem. A hard sphere collision model is used, and subsequently a correction to account for the flow behaviour of air is incorporated. Our calculations prove the affinity laws and provide numerical estimates of the air delivery, thrust and drag on a rotating fan.
A new series of emodin derivatives with bone affinity
Institute of Scientific and Technical Information of China (English)
Hong Chen; Ying Wang; Ling Leng; Mao Sheng Cheng; Peng Fei Yu; Jing Ze Zhang
2007-01-01
A new series of bone affinity compounds were synthesized by linking emodin with 5-fluorouracil derivatives. Their bone affinities were established by hydroxyapative (HA) affinity experiment in vitro, and their cytostatic effects were shown by the MTT assay.
Synthesis of a New Series of Bone Affinity Compounds
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
A new series of bone affinity compounds were synthesized by linking chrysophanol with 5-fluorouracil derivatives. Their bone affinity was established by hydroxyapafive (HA)affinity experiment in vitro, and their cytostatic effects were shown by the MTT assay.
The connection between metal ion affinity and ligand affinity in integrin I domains
DEFF Research Database (Denmark)
Vorup-Jensen, Thomas; Waldron, TT; Astrof, N;
2007-01-01
Integrins are cell-surface heterodimeric proteins that mediate cell-cell, cell-matrix, and cell-pathogen interactions. Half of the known integrin alpha subunits contain inserted domains (I domains) that coordinate ligand through a metal ion. Although the importance of conformational changes within...... isolated I domains in regulating ligand binding has been reported, the relationship between metal ion binding affinity and ligand binding affinity has not been elucidated. Metal and ligand binding by several I domain mutants that are stabilized in different conformations are investigated using isothermal...... titration calorimetry and surface plasmon resonance studies. This work suggests an inverse relationship between metal ion affinity and ligand binding affinity (i.e. constructs with a high affinity for ligand exhibit a low affinity for metal). This trend is discussed in the context of structural studies...
Food and value motivation: Linking consumer affinities to different types of food products.
de Boer, Joop; Schösler, Hanna
2016-08-01
This study uses the consumer affinity concept to examine the multiple motives that may shape consumers' relationships with food. The concept was applied in a study on four broad product types in the Netherlands, which cover a wide range of the market and may each appeal to consumers with different affinities towards foods. These product types may be denoted as 'conventional', 'efficient', 'gourmet' and 'pure'. A comparative analysis, based on Higgins' Regulatory Focus Theory, was performed to examine whether food-related value motivations could explain different consumer affinities for these product types. The affinities of consumers were measured by means of a non-verbal, visual presentation of four samples of food products in a nationwide survey (n = 742) among consumers who were all involved in food purchasing and/or cooking. The affinities found could be predicted fairly well from a number of self-descriptions relating to food and eating, which expressed different combinations of type of value motivation and involvement with food. The analysis demonstrated the contrasting role of high and low involvement as well as the potential complementarity of promotion- and prevention-focused value motivation. It is suggested that knowledge of the relationships between product types, consumer affinities and value motivation can help improve the effectiveness of interventions that seek to promote healthy and sustainable diets in developed countries.
Shape of optimal active flagella
Eloy, Christophe
2013-01-01
Many eukaryotic cells use the active waving motion of flexible flagella to self-propel in viscous fluids. However, the criteria governing the selection of particular flagellar waveforms among all possible shapes has proved elusive so far. To address this question, we derive computationally the optimal shape of an internally-forced periodic planar flagellum deforming as a travelling wave. The optimum is here defined as the shape leading to a given swimming speed with minimum energetic cost. To calculate the energetic cost though, we consider the irreversible internal power expanded by the molecular motors forcing the flagellum, only a portion of which ending up dissipated in the fluid. This optimisation approach allows us to derive a family of shapes depending on a single dimensionless number quantifying the relative importance of elastic to viscous effects: the Sperm number. The computed optimal shapes are found to agree with the waveforms observed on spermatozoon of marine organisms, thus suggesting that the...
Institute of Scientific and Technical Information of China (English)
黄青青
2015-01-01
The comments on The Seven Sisters by the well-known female writer Margaret Drabble in 2002 have never concerned the textual exploration under the double perspectives of the power theory of Michel Foucault and the tension theory in New Criticism .Orien-ted by Michel Foucault 's power theory , this paper attempts to dig into the tension lurking in the text under the framework of the tension theory in New Criticism , in order to demonstrate the heroine 's position in the power circle , as well as the process of deconstructing and reconstructing her power view , showing her determination to shape a brand-new image .%英国知名女作家玛格丽特· 德拉布尔2002年的作品 《七姐妹》 的评论, 从未涉及在米歇尔· 福柯的权力理论和新批评的张力理论双重观照下的文本探索. 文章以米歇尔· 福柯的权力理论为向导, 在新批评的张力理论框架下, 挖掘深藏于文本内部的张力, 以探析女主人公在权力网中的位置以及她权力观的自我解构和建构历程, 展现其渴望形塑全新自我的决心.
Dual-tagging system for the affinity purification of mammalian protein complexes
Energy Technology Data Exchange (ETDEWEB)
Giannone, Richard J [ORNL; McDonald, W Hayes [ORNL; Hurst, Gregory {Greg} B [ORNL; Huang, Ying [ORNL; Wu, Jun [ORNL; Liu, Yie [National Institute on Aging, Baltimore; Wang, Yisong [ORNL
2007-01-01
Although affinity purification coupled with mass spectrometry (MS) provides a powerful tool to study protein-protein interactions, this strategy has encountered numerous difficulties when adapted to mammalian cells. Here we describe a Gateway{reg_sign}-compatible dual-tag affinity purification system that integrates regulatable expression, tetracysteine motifs, and various combinations of affinity tags to facilitate the cloning, detection, and purification of bait proteins and their interacting partners. Utilizing the human telomere binding protein TRF2 as a benchmark, we demonstrate bait protein recoveries upwards of approximately 16% from as little as 1-7 x 10{sup 7} cells and successfully identify known TRF2 interacting proteins, suggesting that our dual-tag affinity purification approach is a capable new tool for expanding the capacity to explore mammalian proteomic networks.
基于脉冲成型的降低FBMC系统峰均比方法%Solution to Peak-to-Average Power Ration in FBMC Based on Pulse Shaping
Institute of Scientific and Technical Information of China (English)
李扬; 郭树旭; 李铨
2011-01-01
In order to solve the high PAPR ( Peak to Average Power Ration ) problem in FBMC ( Filter Bank MmultiCarrier ) system, based on the prototype filter and its polyphase structure in FBMC system, a solution is proposed to reduce PAPR in FBMC system using pulse shaping technique, which borrows ideas from solutions to reduce PAPR in OFDM ( Orthogonal Frequency Division Multiplexing ) system. The cyclic shifting is implemented in time-domain by adding weighting in frequency-domain after S/P ( Serial to Parallel ) in synthesis filer banks, thereby the reduction of PAPR is accomplished. The simulation results indicate that PAPR is obviously reduced after importing PS in FBMC system.%针对滤波器组多载波(FBMC:Filter Bank MultiCarrier)系统峰均比(PAPR:Peak to Average Power Ration)较高的问题,基于FBMC系统中原型滤波器及其多项结构,借鉴正交频分复用(OFDM:Orthogonal Frequency Division Multiplexing)降低峰均比方法,提出一种基于脉冲成型(PS:Pulse Shaping)技术的降低FBMC系统峰均比的方法.该方法在综合滤波器S/P(Serial to Parallel)后添加频率加权,实现了时域的循环位移,从而达到降低峰均比的目的.仿真结果表明,在FBMC系统中引入PS技术后,峰均比有明显下降.
Food and value motivation: Linking consumer affinities to different types of food products
Boer, de, J.H.; Schosler, H.
2016-01-01
This study uses the consumer affinity concept to examine the multiple motives that may shape consumers’ relationships with food. The concept was applied in a study on four broad product types in the Netherlands, which cover a wide range of the market and may each appeal to consumers with different affinities towards foods. These product types may be denoted as ‘conventional’, ‘efficient’, ‘gourmet’ and ‘pure’. A comparative analysis, based on Higgins’ Regulatory Focus Theory, was performed to...
Research on Lead Power of Government Micro-blog in Shaping Public Opinion%利用政府微博引导公众舆论
Institute of Scientific and Technical Information of China (English)
蓝庆专
2012-01-01
At present our society is in the transition period. Because of the diversification of individual interests, social problems are increasing and the public mood is easy to produce the fluctuation which blocks public opinion to positive direction. Government micro-blog,with its unique attribute, is a essential means to achieve the positive interaction of government. In addition, it is an effective bridge of network public opinion and traditional public opinion. What's more,it is also a powerful tool to combat vicious opinions. But at the same time, government micro-blog needs continual improvement. Government departments should focus on changes of ideas and innovation of concept, in order to make the full uses of micro-blog to guide the public opinion to the right direction.% 目前我国社会正处于转型期。由于利益主体的多元化，社会问题也随之增多，公众情绪易波动，从而影响公众舆论的正面发展。政府微博因其独特的属性，是实现政府与公众良性互动的重要手段，也是联结网络舆论与传统媒介舆论的有效桥梁，更是打击恶性舆论的有力工具。但同时，政府微博自身也存在诸多待改进之处。政府部门应注重观念转变、内容创新，利用微博传播信息的优越性，引导公众舆论向积极健康的方向发展
Energy Technology Data Exchange (ETDEWEB)
Boyer, M. D.; Andre, R.; Gates, D. A.; Gerhardt, S.; Goumiri, I. R.; Menard, J.
2015-04-24
The high-performance operational goals of NSTX-U will require development of advanced feedback control algorithms, including control of ßN and the safety factor profile. In this work, a novel approach to simultaneously controlling ßN and the value of the safety factor on the magnetic axis, q0, through manipulation of the plasma boundary shape and total beam power, is proposed. Simulations of the proposed scheme show promising results and motivate future experimental implementation and eventual integration into a more complex current profile control scheme planned to include actuation of individual beam powers, density, and loop voltage. As part of this work, a flexible framework for closed loop simulations within the high-fidelity code TRANSP was developed. The framework, used here to identify control-design-oriented models and to tune and test the proposed controller, exploits many of the predictive capabilities of TRANSP and provides a means for performing control calculations based on user-supplied data (controller matrices, target waveforms, etc.). The flexible framework should enable high-fidelity testing of a variety of control algorithms, thereby reducing the amount of expensive experimental time needed to implement new control algorithms on NSTX-U and other devices.
Classification of neocortical interneurons using affinity propagation
Santana, Roberto; McGarry, Laura M.; Bielza, Concha; Larrañaga, Pedro; Yuste, Rafael
2013-01-01
In spite of over a century of research on cortical circuits, it is still unknown how many classes of cortical neurons exist. In fact, neuronal classification is a difficult problem because it is unclear how to designate a neuronal cell class and what are the best characteristics to define them. Recently, unsupervised classifications using cluster analysis based on morphological, physiological, or molecular characteristics, have provided quantitative and unbiased identification of distinct neuronal subtypes, when applied to selected datasets. However, better and more robust classification methods are needed for increasingly complex and larger datasets. Here, we explored the use of affinity propagation, a recently developed unsupervised classification algorithm imported from machine learning, which gives a representative example or exemplar for each cluster. As a case study, we applied affinity propagation to a test dataset of 337 interneurons belonging to four subtypes, previously identified based on morphological and physiological characteristics. We found that affinity propagation correctly classified most of the neurons in a blind, non-supervised manner. Affinity propagation outperformed Ward's method, a current standard clustering approach, in classifying the neurons into 4 subtypes. Affinity propagation could therefore be used in future studies to validly classify neurons, as a first step to help reverse engineer neural circuits. PMID:24348339
Classification of neocortical interneurons using affinity propagation.
Santana, Roberto; McGarry, Laura M; Bielza, Concha; Larrañaga, Pedro; Yuste, Rafael
2013-01-01
In spite of over a century of research on cortical circuits, it is still unknown how many classes of cortical neurons exist. In fact, neuronal classification is a difficult problem because it is unclear how to designate a neuronal cell class and what are the best characteristics to define them. Recently, unsupervised classifications using cluster analysis based on morphological, physiological, or molecular characteristics, have provided quantitative and unbiased identification of distinct neuronal subtypes, when applied to selected datasets. However, better and more robust classification methods are needed for increasingly complex and larger datasets. Here, we explored the use of affinity propagation, a recently developed unsupervised classification algorithm imported from machine learning, which gives a representative example or exemplar for each cluster. As a case study, we applied affinity propagation to a test dataset of 337 interneurons belonging to four subtypes, previously identified based on morphological and physiological characteristics. We found that affinity propagation correctly classified most of the neurons in a blind, non-supervised manner. Affinity propagation outperformed Ward's method, a current standard clustering approach, in classifying the neurons into 4 subtypes. Affinity propagation could therefore be used in future studies to validly classify neurons, as a first step to help reverse engineer neural circuits.
Proton Affinity Calculations with High Level Methods.
Kolboe, Stein
2014-08-12
Proton affinities, stretching from small reference compounds, up to the methylbenzenes and naphthalene and anthracene, have been calculated with high accuracy computational methods, viz. W1BD, G4, G3B3, CBS-QB3, and M06-2X. Computed and the currently accepted reference proton affinities are generally in excellent accord, but there are deviations. The literature value for propene appears to be 6-7 kJ/mol too high. Reported proton affinities for the methylbenzenes seem 4-5 kJ/mol too high. G4 and G3 computations generally give results in good accord with the high level W1BD. Proton affinity values computed with the CBS-QB3 scheme are too low, and the error increases with increasing molecule size, reaching nearly 10 kJ/mol for the xylenes. The functional M06-2X fails markedly for some of the small reference compounds, in particular, for CO and ketene, but calculates methylbenzene proton affinities with high accuracy.
Specification of ROP flux shape
Energy Technology Data Exchange (ETDEWEB)
Min, Byung Joo [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Gray, A. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)
1997-06-01
The CANDU 9 480/SEU core uses 0.9% SEU (Slightly Enriched Uranium) fuel. The use f SEU fuel enables the reactor to increase the radial power form factor from 0.865, which is typical in current natural uranium CANDU reactors, to 0.97 in the nominal CANDU 9 480/SEU core. The difference is a 12% increase in reactor power. An additional 5% increase can be achieved due to a reduced refuelling ripple. The channel power limits were also increased by 3% for a total reactor power increase of 20%. This report describes the calculation of neutron flux distributions in the CANDU 9 480/SEU core under conditions specified by the C and I engineers. The RFSP code was used to calculate of neutron flux shapes for ROP analysis. Detailed flux values at numerous potential detector sites were calculated for each flux shape. (author). 6 tabs., 70 figs., 4 refs.
Institute of Scientific and Technical Information of China (English)
彭军; 袁宝慧; 程淑杰; 陈皓
2011-01-01
Through six shot ballistics limit law with 14. S mm ballistic gun and LS-DYNA, the ballistic limit speed of 8 g cube-shaped steel fragments and 3 g, 8 g cube-shaped tungsten-alloy fragments, vertically penetrating the Q235 steel target, is studied, and the piercing mechanism and armor-piercing power of three the types of fragmentation near the ballistic limit speed are also analyzed. The results show that the mechanism of three types of fragments is same. In the case of similar impact specific kinetic energy, the fragment density is the main factor affecting armor-piercing power, when the fragment penetrates 5 mm steel target; but the density and quality of fragments decide the fragment armor-piercing power together when penetrating 10 mm steel target.%利用14.5 mm弹道枪通过六射弹弹道极限法,结合LS-DYNA数值计算法研究了8 g立方形钢破片和3 g、8 g立方形钨合金破片垂直侵彻Q235钢靶板的v50弹道极限速度,并分析了三种类型破片在v50弹道极限速度附近的穿甲机理、穿甲威力等.结果表明,三种破片在侵彻靶板时具有相同的穿甲机理,两种类型的钨合金破片具有良好的穿甲效果.在冲击比动能相差不大的情况下,贯穿5mm靶时,破片材料的密度是影响穿甲威力的主要因素；而贯穿10 mm靶时,破片的密度和质量共同决定着破片的穿甲威力.
The high-affinity immunoglobulin E receptor as pharmacological target.
Blank, Ulrich; Charles, Nicolas; Benhamou, Marc
2016-05-05
The high-affinity receptor for immunoglobulin E is expressed mainly on mast cells and basophils, but also on neutrophils, eosinophils, platelets, monocytes, Langerhans and dendritic cells, airway smooth muscle cells and some nerve cells. Its main function is, upon its engagement by IgE and specific antigen, to trigger a powerful defense against invading pathogens and a rapid neutralization of dangerous toxic substances introduced in the body. This powerful response could be wielded against tumors. But, when control over this receptor is lost, its unchecked activation can induce an array of diseases, some of which can lead to death. In this review we will summarize the pharmacological approaches and strategies that are currently used, or under study, to harness or wield activation of this receptor for therapeutic purposes.
Stepparents' Affinity-Seeking and Affinity-Maintaining Strategies with Stepchildren.
Ganong, Lawrence; Coleman, Marilyn; Fine, Mark; Martin, Patricia
1999-01-01
Examines the strategies that stepparents use to develop and maintain affinity with stepchildren and the effects that these strategies have on the development of stepparent-stepchildren relationships. Thirty-one affinity-seeking strategies are identified. Results show that dyadic activities worked best, but it is important that stepchildren…
New opioid affinity labels containing maleoyl moiety.
Szatmári, I; Orosz, G; Rónai, A Z; Makó, E; Medzihradszky, K; Borsodi, A
1999-01-01
Opioid receptor binding properties and pharmacological profiles of novel peptides containing maleoyl function were determined in order to develop new affinity labels. Based on the enkephalin structure peptide ligands were synthesized and tested. Both in in vitro receptor binding experiments and pharmacological studies, all ligands showed agonist character with relatively high affinity (Ki values in the nanomolar range) and good to moderate selectivity. Replacement of Gly2 in the enkephalin frame with D-Ala led to higher affinities with a small decrease in selectivity. The longer peptide chains resulted in compounds with high percentage (up to 86%) of irreversible binding. The selectivity pattern of the ligands is in good agreement with the data obtained from the pharmacological assays (guinea pig ileum and mouse vas deferens bioassays). The newly synthesized peptides could be used in further studies in order to determine more detailed characteristics of the ligand-receptor interaction.
On Affine Fusion and the Phase Model
Directory of Open Access Journals (Sweden)
Mark A. Walton
2012-11-01
Full Text Available A brief review is given of the integrable realization of affine fusion discovered recently by Korff and Stroppel. They showed that the affine fusion of the su(n Wess-Zumino-Novikov-Witten (WZNW conformal field theories appears in a simple integrable system known as the phase model. The Yang-Baxter equation leads to the construction of commuting operators as Schur polynomials, with noncommuting hopping operators as arguments. The algebraic Bethe ansatz diagonalizes them, revealing a connection to the modular S matrix and fusion of the su(n WZNW model. The noncommutative Schur polynomials play roles similar to those of the primary field operators in the corresponding WZNW model. In particular, their 3-point functions are the su(n fusion multiplicities. We show here how the new phase model realization of affine fusion makes obvious the existence of threshold levels, and how it accommodates higher-genus fusion.
Modelling and simulation of affinity membrane adsorption.
Boi, Cristiana; Dimartino, Simone; Sarti, Giulio C
2007-08-24
A mathematical model for the adsorption of biomolecules on affinity membranes is presented. The model considers convection, diffusion and adsorption kinetics on the membrane module as well as the influence of dead end volumes and lag times; an analysis of flow distribution on the whole system is also included. The parameters used in the simulations were obtained from equilibrium and dynamic experimental data measured for the adsorption of human IgG on A2P-Sartoepoxy affinity membranes. The identification of a bi-Langmuir kinetic mechanisms for the experimental system investigated was paramount for a correct process description and the simulated breakthrough curves were in good agreement with the experimental data. The proposed model provides a new insight into the phenomena involved in the adsorption on affinity membranes and it is a valuable tool to assess the use of membrane adsorbers in large scale processes.
Poisson Morphisms and Reduced Affine Poisson Group Actions
Institute of Scientific and Technical Information of China (English)
YANG Qi Lin
2002-01-01
We establish the concept of a quotient affine Poisson group, and study the reduced Poisson action of the quotient of an affine Poisson group G on the quotient of an affine Poisson G-variety V. The Poisson morphisms (including equivariant cases) between Poisson affine varieties are also discussed.
Periodic cyclic homology of affine Hecke algebras
Solleveld, Maarten
2009-01-01
This is the author's PhD-thesis, which was written in 2006. The version posted here is identical to the printed one. Instead of an abstract, the short list of contents: Preface 5 1 Introduction 9 2 K-theory and cyclic type homology theories 13 3 Affine Hecke algebras 61 4 Reductive p-adic groups 103 5 Parameter deformations in affine Hecke algebras 129 6 Examples and calculations 169 A Crossed products 223 Bibliography 227 Index 237 Samenvatting 245 Curriculum vitae 253
Einstein's gravity from an affine model
Castillo-Felisola, Oscar
2015-01-01
We show that the effective field equations for a recently formulated affine model of gravity, in the sector of a metric (torsion-free) connection, accept general Einstein manifolds --- with or without cosmological constant --- as solutions. Moreover, these effective field equations coincide with the ones obtained from a gravitational Yang--Mills theory known as Stephenson--Kilmister--Yang theory. Additionally, we find an equivalence between a minimally coupled massless scalar field in General Relativity with a "minimally" coupled scalar field in this affine model.
Separation of Proteins by Electrophoretic Affinity Chromatography
Institute of Scientific and Technical Information of China (English)
邺韶骅; 刘铮; 丁富新; 袁乃驹
1999-01-01
A new kind of electrophoretic affinity chromatography (EAC) for bioseparation was proposed,Separation by EAC was conducted in a multicompartment electrolyzer in which the affinity gel media were packed in one of the central compartments.The presence of an electric field accelerated the migration of proteins inside the gel matrix during adsorption and descrption processes,This led to the increase of the overall speed of separation,The present study was focused on the effect of the strength of the electric field on adsorption and desorption processes.
Adsorption affinity of anions on metal oxyhydroxides
Pechenyuk, S. I.; Semushina, Yu. P.; Kuz'mich, L. F.
2013-03-01
The dependences of anion (phosphate, carbonate, sulfate, chromate, oxalate, tartrate, and citrate) adsorption affinity anions from geometric characteristics, acid-base properties, and complex forming ability are generalized. It is shown that adsorption depends on the nature of both the anions and the ionic medium and adsorbent. It is established that anions are generally grouped into the following series of adsorption affinity reduction: PO{4/3-}, CO{3/2-} > C2O{4/2-}, C(OH)(CH2)2(COO){3/3-}, (CHOH)2(COO){2/2-} > CrO{4/2-} ≫ SO{4/2-}.
Affine Invariant Character Recognition by Progressive Removing
Iwamura, Masakazu; Horimatsu, Akira; Niwa, Ryo; Kise, Koichi; Uchida, Seiichi; Omachi, Shinichiro
Recognizing characters in scene images suffering from perspective distortion is a challenge. Although there are some methods to overcome this difficulty, they are time-consuming. In this paper, we propose a set of affine invariant features and a new recognition scheme called “progressive removing” that can help reduce the processing time. Progressive removing gradually removes less feasible categories and skew angles by using multiple classifiers. We observed that progressive removing and the use of the affine invariant features reduced the processing time by about 60% in comparison to a trivial one without decreasing the recognition rate.
Phosphopeptide enrichment by immobilized metal affinity chromatography
DEFF Research Database (Denmark)
Thingholm, Tine E.; Larsen, Martin R.
2016-01-01
Immobilized metal affinity chromatography (IMAC) has been the method of choice for phosphopeptide enrichment prior to mass spectrometric analysis for many years and it is still used extensively in many laboratories. Using the affinity of negatively charged phosphate groups towards positively...... charged metal ions such as Fe3+, Ga3+, Al3+, Zr4+, and Ti4+ has made it possible to enrich phosphorylated peptides from peptide samples. However, the selectivity of most of the metal ions is limited, when working with highly complex samples, e.g., whole-cell extracts, resulting in contamination from...
Evidence of multi-affinity in the Japanese stock market
Katsuragi, Hiroaki
2000-04-01
Fluctuations of the Japanese stock market (Tokyo Stock Price Index: TOPIX) are analyzed using a multi-affine analysis method. In the research to date, only some simulated self-affine models have shown multi-affinity. In most experiments using observations of self-affine fractal profiles, multi-affinity has not been found. However, we find evidence of multi-affinity in fluctuations of the Japanese stock market (TOPIX). The qth-order Hurst exponent Hq varies with changes in q. This multi-affinity indicates that there are plural mechanisms that affect the same time scale as stock market price fluctuation dynamics.
Crossing Chris: Some Markerian Affinities
Directory of Open Access Journals (Sweden)
Adrian Martin
2010-01-01
-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}
Abstract (E: This essay creatively explores a group of artists, writers, and other special individuals whose work or life story can be described as having an intriguing affinity with the protean career of Chris Marker. Avoiding the ‘usual suspects’ (such as Godard or Sebald, it discusses gossip columnist Milt Machlin, record collector Harry Smith, painter Gianfranco Baruchello, writer-filmmaker Edgardo Cozarinsky, and several others. From this constellation, a particular view of Markerian poetics emerges, touching upon the meanings of anonymity, storytelling, history and archiving.
Abstract (F: Cet essai brosse de manière créative le portrait d’un groupe d'artistes, d'écrivains et d'autres personnes particulières dont le travail ou la biographie peuvent être décrits comme montrant une étrange mais certaine connivence avec la carrière protéiforme de Chris Marker. Evitant les lieux communs (comme Godard ou Sebald, cet article trace des références moins attendues :
High affinity germinal center B cells are actively selected into the plasma cell compartment.
Phan, Tri Giang; Paus, Didrik; Chan, Tyani D; Turner, Marian L; Nutt, Stephen L; Basten, Antony; Brink, Robert
2006-10-30
A hallmark of T cell-dependent immune responses is the progressive increase in the ability of serum antibodies to bind antigen and provide immune protection. Affinity maturation of the antibody response is thought to be connected with the preferential survival of germinal centre (GC) B cells that have acquired increased affinity for antigen via somatic hypermutation of their immunoglobulin genes. However, the mechanisms that drive affinity maturation remain obscure because of the difficulty in tracking the affinity-based selection of GC B cells and their differentiation into plasma cells. We describe a powerful new model that allows these processes to be followed as they occur in vivo. In contrast to evidence from in vitro systems, responding GC B cells do not undergo plasma cell differentiation stochastically. Rather, only GC B cells that have acquired high affinity for the immunizing antigen form plasma cells. Affinity maturation is therefore driven by a tightly controlled mechanism that ensures only antibodies with the greatest possibility of neutralizing foreign antigen are produced. Because the body can sustain only limited numbers of plasma cells, this "quality control" over plasma cell differentiation is likely critical for establishing effective humoral immunity.
Institute of Scientific and Technical Information of China (English)
BRADLEY GARDNER
2008-01-01
@@ Bill Emmott's new book,Rivals:How the Power Struggle Between China,India and Japan Will Shape Our Next Decade,is an investigation of the problematic relationship between China,India,and Japan,as two of those countries begin to assert themselves on the world stage,and how the situation could result in all-out conflict.
GPU-ASIFT : A Fast Fully Affine-Invariant Feature Extraction Algorithm
Codreanu, Valeriu; Dong, Feng; Liu, Baoquan; Roerdink, Jos B.T.M.; Williams, David; Yang, Po; Yasar, Burhan
2013-01-01
This paper presents a method that takes advantage of powerful graphics hardware to obtain fully affine-invariant image feature detection and matching. The chosen approach is the accurate, but also very computationally expensive, ASIFT algorithm. We have created a CUDA version of this algorithm that
High-affinity olfactory receptor for the death-associated odor cadaverine
2013-01-01
Cadaverine and putrescine, two diamines emanating from decaying flesh, are strongly repulsive odors to humans but serve as innate attractive or social cues in other species. Here we show that zebrafish, a vertebrate model system, exhibit powerful and innate avoidance behavior to both diamines, and identify a high-affinity olfactory receptor for cadaverine.
Fan Affinity Laws from a Collision Model
Bhattacharjee, Shayak
2012-01-01
The performance of a fan is usually estimated using hydrodynamical considerations. The calculations are long and involved and the results are expressed in terms of three affinity laws. In this paper we use kinetic theory to attack this problem. A hard sphere collision model is used, and subsequently a correction to account for the flow behaviour…
Colliding waves in metric-affine gravity
García, A; Macías, A; Mielke, E W; Socorro, J; García, Alberto; Lämmerzahl, Claus; Macías, Alfredo; Mielke, Eckehard W.; Socorro, José
1998-01-01
We generalize the formulation of the colliding gravitational waves to metric-affine theories and present an example of such kind of exact solutions. The plane waves are equipped with five symmetries and the resulting geometry after the collision possesses two spacelike Killing vectors.
Classification of neocortical interneurons using affinity propagation
Directory of Open Access Journals (Sweden)
Roberto eSantana
2013-12-01
Full Text Available In spite of over a century of research on cortical circuits, it is still unknown how many classes of cortical neurons exist. Neuronal classification has been a difficult problem because it is unclear what a neuronal cell class actually is and what are the best characteristics are to define them. Recently, unsupervised classifications using cluster analysis based on morphological, physiological or molecular characteristics, when applied to selected datasets, have provided quantitative and unbiased identification of distinct neuronal subtypes. However, better and more robust classification methods are needed for increasingly complex and larger datasets. We explored the use of affinity propagation, a recently developed unsupervised classification algorithm imported from machine learning, which gives a representative example or exemplar for each cluster. As a case study, we applied affinity propagation to a test dataset of 337 interneurons belonging to four subtypes, previously identified based on morphological and physiological characteristics. We found that affinity propagation correctly classified most of the neurons in a blind, non-supervised manner. In fact, using a combined anatomical/physiological dataset, our algorithm differentiated parvalbumin from somatostatin interneurons in 49 out of 50 cases. Affinity propagation could therefore be used in future studies to validly classify neurons, as a first step to help reverse engineer neural circuits.
DEFF Research Database (Denmark)
Heegaard, N H; Sen, J W; Nissen, Mogens Holst
2000-01-01
The amyloidogenic protein beta-microglobulin was characterized by affinity capillary electrophoresis (CE). CE could separate conformational variants of beta2-microglobulin and with the amyloid-specific dye Congo red as a buffer additive it was possible to measure different Congo red-affinities of......The amyloidogenic protein beta-microglobulin was characterized by affinity capillary electrophoresis (CE). CE could separate conformational variants of beta2-microglobulin and with the amyloid-specific dye Congo red as a buffer additive it was possible to measure different Congo red...
Monzo, Alex; Olajos, Marcell; De Benedictis, Lorenzo; Rivera, Zuly; Bonn, Guenther K; Guttman, András
2008-09-01
As a continuation of our work on boronic acid lectin affinity chromatography (BLAC), in this paper we introduce an automated affinity micropartitioning approach using combined boronic acid and concanavalin A (BLAC/Con A) resin-filled micropipette tips to isolate and enrich human serum glycoproteins. The N-linked oligosaccharides of the partitioned glycoproteins were removed by PNGase F enzyme digestion, followed by 8-aminopyrene-1,3,6-trisulfonic acid labeling. Capillary gel electrophoresis with blue LED-induced fluorescence detection was applied in a multiplexed format for comparative glycan profiling. The efficiency of BLAC affinity micropartitioning was compared with that of the individual lectin and pseudolectin affinity enrichment. Finally, we report on our findings in glycosylation differences in human serum samples from healthy and prostate cancer patients by applying BLAC/Con A micropipette tip-based enrichment and comparative multicapillary gel electrophoresis analysis of the released and labeled glycans.
Purification of coagulation factor VIII by immobilized metal affinity chromatography.
Rodrigues, Estela S; Verinaud, Claudia I; Oliveira, Douglas S; Raw, Isaías; Lopes, Alexandre P Y; Martins, Elizabeth A L; Cheng, Elisabeth
2015-01-01
Factor VIII (FVIII) is a glycoprotein that plays an essential role in blood coagulation cascade. Purification of plasma-derived coagulation FVIII by direct application of plasma to a chromatographic column is a method of choice. Anion exchange column is a very powerful method because FVIII is strongly adsorbed, resulting in good activity recovery and high purification factor. However, vitamin-K-dependent coagulation factors coelute with FVIII. In the present study, we report the separation of vitamin-K-dependent coagulation proteins from FVIII using immobilized metal affinity chromatography (IMAC) with Cu(2+) as the metal ligand. Plasma was directly loaded to a Q Sepharose Big Beads column, and FVIII was recovered with 65% activity and a purification factor of approximately 50 times. Then, the Q Sepharose eluate was applied to the IMAC-Cu(2+) column, and FVIII was eluted with 200 mM imidazole, with up to 85% recovery of activity. The mass recovery in this fraction was less than 10% of the applied mass of protein. Vitamin-K-dependent proteins elute with imidazole concentrations of lower than 60 mM. Because of the difference in affinity, FVIII could be completely separated from the vitamin-K-dependent proteins in the IMAC column.
Self-affinity in the dengue fever time series
Azevedo, S. M.; Saba, H.; Miranda, J. G. V.; Filho, A. S. Nascimento; Moret, M. A.
2016-06-01
Dengue is a complex public health problem that is common in tropical and subtropical regions. This disease has risen substantially in the last three decades, and the physical symptoms depict the self-affine behavior of the occurrences of reported dengue cases in Bahia, Brazil. This study uses detrended fluctuation analysis (DFA) to verify the scale behavior in a time series of dengue cases and to evaluate the long-range correlations that are characterized by the power law α exponent for different cities in Bahia, Brazil. The scaling exponent (α) presents different long-range correlations, i.e. uncorrelated, anti-persistent, persistent and diffusive behaviors. The long-range correlations highlight the complex behavior of the time series of this disease. The findings show that there are two distinct types of scale behavior. In the first behavior, the time series presents a persistent α exponent for a one-month period. For large periods, the time series signal approaches subdiffusive behavior. The hypothesis of the long-range correlations in the time series of the occurrences of reported dengue cases was validated. The observed self-affinity is useful as a forecasting tool for future periods through extrapolation of the α exponent behavior. This complex system has a higher predictability in a relatively short time (approximately one month), and it suggests a new tool in epidemiological control strategies. However, predictions for large periods using DFA are hidden by the subdiffusive behavior.
Targeting Anti-Cancer Active Compounds: Affinity-Based Chromatographic Assays
de Moraes, Marcela Cristina; Cardoso, Carmen Lucia; Seidl, Claudia; Moaddel, Ruin; Cass, Quezia Bezerra
2016-01-01
Affinity-based chromatography assays encompass the use of solid supports containing immobilized biological targets to monitor binding events in the isolation , identification and/or characterization of bioactive compounds. This powerful bioanalytical technique allows the screening of potential binders through fast analyses that can be directly performed using isolated substances or complex matrices. An overview of the recent researches in frontal and zonal affinity-based chromatography screening assays, which has been used as a tool in the identification and characterization of new anti-cancer agents, is discussed. In addition, a critical evaluation of the recently emerged ligands fishing assays in complex mixtures is also discussed. PMID:27306095
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
Combinatorial peptide libraries have become powerful tools to screen functional ligands by the principle of affinity selection. We screened in a phage peptide library to investigate potential peptide affinity ligands for the purification of human granulocyte colony-stimulation factor(hG-CSF). Peptide ligands will be promising to replace monoclonal antibodies as they have advantages of high stability, efficiency, selectivity and low price.
Artificial Affinity Proteins as Ligands of Immunoglobulins
Directory of Open Access Journals (Sweden)
Barbara Mouratou
2015-01-01
Full Text Available A number of natural proteins are known to have affinity and specificity for immunoglobulins. Some of them are widely used as reagents for detection or capture applications, such as Protein G and Protein A. However, these natural proteins have a defined spectrum of recognition that may not fit specific needs. With the development of combinatorial protein engineering and selection techniques, it has become possible to design artificial affinity proteins with the desired properties. These proteins, termed alternative scaffold proteins, are most often chosen for their stability, ease of engineering and cost-efficient recombinant production in bacteria. In this review, we focus on alternative scaffold proteins for which immunoglobulin binders have been identified and characterized.
Local structure of self-affine sets
Bandt, Christoph
2011-01-01
The structure of a self-similar set with open set condition does not change under magnification. For self-affine sets the situation is completely different. We consider planar self-affine Cantor sets E of the type studied by Bedford, McMullen, Gatzouras and Lalley, for which the projection onto the horizontal axis is an interval. We show that within small square neighborhoods of almost each point x in E, with respect to many product measures on address space, E is well approximated by product sets of an interval and a Cantor set. Even though E is totally disconnected, the limit sets have the product structure with interval fibres, reminiscent to the view of attractors of chaotic differentiable dynamical systems.
Thermodynamics. Using Affinities to define reversible processes
Ritacco, Hernán A
2016-01-01
In this article a definition of reversible processes in terms of differences in intensive Thermodynamics properties (Affinities) is proposed. This definition makes it possible to both define reversible processes before introducing the concept of entropy and avoid the circularity problem that follows from the Clausius definition of entropy changes. The convenience of this new definition compared to those commonly found in textbooks is demonstrated with examples.
Couplings in Affine Toda Field Theories
1992-01-01
We present a systematic derivation for a general formula for the n-point coupling constant valid for affine Toda theories related to any simple Lie algebra {\\bf g}. All n-point couplings with $n \\geq 4$ are completely determined in terms of the masses and the three-point couplings. A general fusing rule, formulated in the root space of the Lie algebra, is derived for all n-point couplings.
Mepanipyrim haptens and antibodies with nanomolar affinity
Esteve Turrillas, Francesc Albert; Mercader Badia, Josep Vicent; Agulló, Consuelo; Abad Somovilla, Antonio; Abad Fuentes, Antonio
2013-01-01
Mepanipyrim is an anilinopyrimidine fungicide used worldwide for crop protection. With the aim of developing useful immunoreagents for mepanipyrim immunoanalysis, two new functionalized derivatives were prepared and antibodies were generated. Affinity and specificity were assessed by direct and indirect competitive ELISA using homologous and heterologous conjugates. Although all antibodies were selective for the target analyte, the immunizing hapten structure was revealed as a determinant for...
Folding defect affine Toda field theories
Robertson, C
2013-01-01
A folding process is applied to fused a^(1)_r defects to construct defects for the non-simply laced affi?ne Toda ?field theories of c^(1)_n, d^(2)_n and a^(2)_n at the classical level. Support for the hypothesis that these defects are integrable in the folded theories is provided by the observation that transmitted solitons retain their form. Further support is given by the demonstration that energy and momentum are conserved.
AFFINE TRANSFORMATION IN RANDOM ITERATED FUNCTION SYSTEMS
Institute of Scientific and Technical Information of China (English)
熊勇; 史定华
2001-01-01
Random iterated function systems (IFSs) is discussed, which is one of the methods for fractal drawing. A certain figure can be reconstructed by a random IFS. One approach is presented to determine a new random IFS, that the figure reconstructed by the new random IFS is the image of the origin figure reconstructed by old IFS under a given affine transformation. Two particular examples are used to show this approach.
On constructing purely affine theories with matter
Cervantes-Cota, Jorge L.; Liebscher, D.-E.
2016-08-01
We explore ways to obtain the very existence of a space-time metric from an action principle that does not refer to it a priori. Although there are reasons to believe that only a non-local theory can viably achieve this goal, we investigate here local theories that start with Schrödinger's purely affine theory (Schrödinger in Space-time structure. Cambridge UP, Cambridge, 1950), where he gave reasons to set the metric proportional to the Ricci curvature aposteriori. When we leave the context of unified field theory, and we couple the non-gravitational matter using some weak equivalence principle, we can show that the propagation of shock waves does not define a lightcone when the purely affine theory is local and avoids the explicit use of the Ricci tensor in realizing the weak equivalence principle. When the Ricci tensor is substituted for the metric, the equations seem to have only a very limited set of solutions. This backs the conviction that viable purely affine theories have to be non-local.
On constructing purely affine theories with matter
Cervantes-Cota, Jorge L
2016-01-01
We explore ways to obtain the very existence of a space-time metric from an action principle that does not refer to it a priori. Although there are reasons to believe that only a non-local theory can viably achieve this goal, we investigate here local theories that start with Schroedinger's purely affine theory [21], where he gave reasons to set the metric proportional to the Ricci curvature aposteriori. When we leave the context of unified field theory, and we couple the non-gravitational matter using some weak equivalence principle, we can show that the propagation of shock waves does not define a lightcone when the purely affine theory is local and avoids the explicit use of the Ricci tensor in realizing the weak equivalence principle. When the Ricci tensor is substituted for the metric, the equations seem to have only a very limited set of solutions. This backs the conviction that viable purely affine theories have to be non-local.
Overview of affinity biosensors in food analysis.
Patel, Pradip D
2006-01-01
The 4 major driving forces that are expected to lead to increased use of affinity biosensors that meet crucial industrial test specifications, e.g., fast, reliable, cost-effective, and use of low-skilled personnel, are (1) strict legislative framework, e.g., recent changes proposed to the European food safety and hygiene legislation, EC No. 178/2002; (2) industrial shift from quality control to quality assurance procedures, e.g., Hazard Analysis Critical Control Point, ensuring effective positioning in the global competitive trade; (3) just-in-time production resulting in 'right' product every time; and (4) consumer demand for safe and wholesome products. The affinity biosensors field has expanded significantly over the past decade, with a projected global biosensors market growth from $6.1 billion in 2004 to $8.2 billion in 2009, representing major industrial sectors (e.g., Pharma, Medicare, and Food). This brief review is targeted to affinity biosensors developed for the food industry and includes research and development leading to biosensors for microbiological and chemical analytes of industrial concern, commercial biosensors products on the market, and examples of future prospects in this diagnostic field.
Directory of Open Access Journals (Sweden)
Marc Behl
2007-04-01
Full Text Available Shape-memory polymers are an emerging class of active polymers that have dual-shape capability. They can change their shape in a predefined way from shape A to shape B when exposed to an appropriate stimulus. While shape B is given by the initial processing step, shape A is determined by applying a process called programming. We review fundamental aspects of the molecular design of suitable polymer architectures, tailored programming and recovery processes, and the quantification of the shape-memory effect. Shape-memory research was initially founded on the thermally induced dual-shape effect. This concept has been extended to other stimuli by either indirect thermal actuation or direct actuation by addressing stimuli-sensitive groups on the molecular level. Finally, polymers are introduced that can be multifunctional. Besides their dual-shape capability, these active materials are biofunctional or biodegradable. Potential applications for such materials as active medical devices are highlighted.
Experimental investigation of streamer affinity for dielectric surfaces
Trienekens, D.J.M.; Nijdam, S.; Akkermans, G.; Plompen, I.; Christen, T.; Ebert, U.
2015-01-01
We have experimentally investigated the affinity of streamers for dielectric surfaces using stroboscopic imaging and stereo photography. Affinity of streamers for dielectric surfaces was found to depend on a wide set of parameters, including pressure, voltage, dielectric material and di
Shape Control of Solar Collectors Using Shape Memory Alloy Actuators
Lobitz, D. W.; Grossman, J. W.; Allen, J. J.; Rice, T. M.; Liang, C.; Davidson, F. M.
1996-01-01
Solar collectors that are focused on a central receiver are designed with a mechanism for defocusing the collector or disabling it by turning it out of the path of the sun's rays. This is required to avoid damaging the receiver during periods of inoperability. In either of these two cases a fail-safe operation is very desirable where during power outages the collector passively goes to its defocused or deactivated state. This paper is principally concerned with focusing and defocusing the collector in a fail-safe manner using shape memory alloy actuators. Shape memory alloys are well suited to this application in that once calibrated the actuators can be operated in an on/off mode using a minimal amount of electric power. Also, in contrast to other smart materials that were investigated for this application, shape memory alloys are capable of providing enough stroke at the appropriate force levels to focus the collector. Design and analysis details presented, along with comparisons to test data taken from an actual prototype, demonstrate that the collector can be repeatedly focused and defocused within accuracies required by typical solar energy systems. In this paper the design, analysis and testing of a solar collector which is deformed into its desired shape by shape memory alloy actuators is presented. Computations indicate collector shapes much closer to spherical and with smaller focal lengths can be achieved by moving the actuators inward to a radius of approximately 6 inches. This would require actuators with considerably more stroke and some alternate SMA actuators are currently under consideration. Whatever SMA actuator is finally chosen for this application, repeatability and fatigue tests will be required to investigate the long term performance of the actuator.
Institute of Scientific and Technical Information of China (English)
刘儒鹏
2015-01-01
During the crucial period of China's rise,Chinese people are mixed with the great power mentality and the victim mentality.On the one hand,they are proud of 5000 years history of China,and on the other hand,they feel inferior because of the hundreds of years of humiliation.All of these are harmful to the rise of China.So it is necessary to shape a healthy mentali-ty through exploring the traditional cultural and the correct guidance of media and join the global governance with a normal state of mind,the sense of responsibility and self-confidence,so as to establish a good mental preparation for the rise of China.%在中国崛起的关键时期，国内民众依然是大国心态与受害者心态的相互交织。一方面是对于中华文明五千年历史的骄傲，另一方面则是对中国百年屈辱史的自卑，这对于崛起中的中国会起到损害作用。因此有必要通过挖掘中国的传统文化，充分发挥媒体的作用，对国民心态进行正确的引导，以平常心、自信心、责任心参与到全球治理中来，为中国的真正崛起做好充分的心理准备。
Spatial model of affinity maturation in germinal centers
Kesmir, C.; Boer, R.J. de
2003-01-01
Affinity maturation of humoral responses to T-cell-dependent antigens occurs in germinal centers (GC). In GCs antigen-specific B cells undergo rounds of somatic mutations that alter their affinity. High-affinity mutants take over GCs very soon after they appear; the replacement rate is as high as 4
Affine Structures on a Ringed Space and Schemes
Institute of Scientific and Technical Information of China (English)
Fengwen AN
2011-01-01
The author first introduces the notion of affine structures on a ringed space and then obtains several related properties. Affine structures on a ringed space, arising from complex analytical spaces of algebraic schenes, behave like differential structures on a smooth nanifold.As one does for differential manifolds, pseudogroups of affine transformations are used to define affine atlases on a ringed space. An atlas on a space is said to be an affine structure if it is maximal. An affine structure is said to be admissible if there is a sheaf on the underlying space such that they are coincide on all affine charts, which are in deed affine open sets of a scheme. In a rigour manner, a scheme is defined to be a ringed space with a specified affine structure if the affine structures make a contribution to the cases such as analytical spaces of algebraic schemes. Particularly, by the whole of affine structures on a pace, two necessary and sufficient conditions, that two spaces are homeomorphic and that two schemes are isomorphic, coming from the main theorems of the paper, are obtained respectively. A conclusion is drawn that the whole of affine structures on a space and a scheme, as local data, encode and reflect the global properties of the space and the scheme,respectively.
Glycation of the high affinity NGF-receptor and RAGE leads to reduced ligand affinity.
Bennmann, Dorit; Kannicht, Christoph; Fisseau, Claudine; Jacobs, Kathleen; Navarette-Santos, Alexander; Hofmann, Britt; Horstkorte, Rüdiger
2015-09-01
AGEs are posttranslational modifications generated by irreversible non-enzymatic crosslinking reactions between sugars and proteins - a reaction referred to as glycation. Glycation, a feature of ageing, can lead to non-degradable and less functional proteins and enzymes and can additionally induce inflammation and further pathophysiological processes such as neurodegeneration. In this study we investigated the influence of glycation on the high affinity NGF-receptor TrkA and the AGE-receptor RAGE. We quantified the binding affinity of the TrkA-receptor and RAGE to their ligands by surface plasmon resonance (SPR) and compared these to the binding affinity after glycation. At the same time, we established a glycation procedure using SPR. We found that glycation of TrkA reduced the affinity to NGF by a factor of three, which could be shown to lead to a reduction of NGF-dependent neurite outgrowth in PC12 cells. Glycation of RAGE reduced binding affinity of AGEs by 10-fold.
Discriminative Shape Alignment
DEFF Research Database (Denmark)
Loog, M.; de Bruijne, M.
2009-01-01
The alignment of shape data to a common mean before its subsequent processing is an ubiquitous step within the area shape analysis. Current approaches to shape analysis or, as more specifically considered in this work, shape classification perform the alignment in a fully unsupervised way......, not taking into account that eventually the shapes are to be assigned to two or more different classes. This work introduces a discriminative variation to well-known Procrustes alignment and demonstrates its benefit over this classical method in shape classification tasks. The focus is on two......-dimensional shapes from a two-class recognition problem....
Wilson, Thomas S.; Bearinger, Jane P.
2015-06-09
New shape memory polymer compositions, methods for synthesizing new shape memory polymers, and apparatus comprising an actuator and a shape memory polymer wherein the shape memory polymer comprises at least a portion of the actuator. A shape memory polymer comprising a polymer composition which physically forms a network structure wherein the polymer composition has shape-memory behavior and can be formed into a permanent primary shape, re-formed into a stable secondary shape, and controllably actuated to recover the permanent primary shape. Polymers have optimal aliphatic network structures due to minimization of dangling chains by using monomers that are symmetrical and that have matching amine and hydroxyl groups providing polymers and polymer foams with clarity, tight (narrow temperature range) single transitions, and high shape recovery and recovery force that are especially useful for implanting in the human body.
The Monitoring and Affinity Purification of Proteins Using Dual-Tags with Tetracysteine Motifs
Energy Technology Data Exchange (ETDEWEB)
Giannone, Richard J [ORNL; Liu, Yie [ORNL; Wang, Yisong [ORNL
2009-01-01
Identification and characterization of protein-protein interaction networks is essential for the elucidation of biochemical mechanisms and cellular function. Affinity purification in combination with liquid chromatography-tandem mass spectrometry (LC-MS/MS) has emerged as a very powerful tactic for the identification of specific protein-protein interactions. In this chapter we describe a comprehensive methodology that utilizes our recently developed dual-tag affinity purification system for the enrichment and identification of mammalian protein complexes. The protocol covers a series of separate but sequentially related techniques focused on the facile monitoring and purification of a dual-tagged protein of interest and its interacting partners via a system built with tetracysteine motifs and various combinations of affinity tags. Using human telomeric repeat binding factor 2 (TRF2) as an example, we have demonstrated the power of the system in terms of bait protein recovery after dual-tag affinity purification, detection of bait protein subcellular localization and expression, and successful identification of known and potentially novel TRF2 interacting proteins. Although the protocol described here has been optimized for the identification and characterization of TRF2-associated proteins, it is, in principle, applicable to the study of any other mammalian protein complexes that may be of interest to the research community.
The Monitoring and Affinity Purification of Proteins Using Dual Tags with Tetracysteine Motifs
Giannone, Richard J.; Liu, Yie; Wang, Yisong
Identification and characterization of protein-protein interaction networks is essential for the elucidation of biochemical mechanisms and cellular function. Affinity purification in combination with liquid chromatography-tandem mass spectrometry (LC-MS/MS) has emerged as a very powerful tactic for the identification of specific protein-protein interactions. In this chapter, we describe a comprehensive methodology that uses our recently developed dual-tag affinity purification system for the enrichment and identification of mammalian protein complexes. The protocol covers a series of separate but sequentially related techniques focused on the facile monitoring and purification of a dual-tagged protein of interest and its interacting partners via a system built with tetracysteine motifs and various combinations of affinity tags. Using human telomeric repeat binding factor 2 (TRF2) as an example, we demonstrate the power of the system in terms of bait protein recovery after dual-tag affinity purification, detection of bait protein subcellular localization and expression, and successful identification of known and potentially novel TRF2 interacting proteins. Although the protocol described here has been optimized for the identification and characterization of TRF2-associated proteins, it is, in principle, applicable to the study of any other mammalian protein complexes that may be of interest to the research community.
Metric-affine gravitation theory and superpotentials
Energy Technology Data Exchange (ETDEWEB)
Giachetta, G.; Mangiarotti, L.; Saltarelli, A. [Camerino, Univ. (Italy). Dipt. di Matematica e Fisica
1997-05-01
They consider a metric-affine theory of gravity in which the dynamical fields are the Lorentzian metrics and the non-symmetric linear connections on the worked manifold X. Working with a Lagrangian density which is invariant under general covariant transformations and using standard tools of the calculus of variations, they study the corresponding currents. They find that the superpotential takes a nice form involving the torsion of the linear connection in a simple way and generalizing the well-known Komar superpotential. A feature of our approach is the use of the Poincare`-Cartan form in relation to the first variational formula of the calculus of variations.
Affinity chromatography with an immobilized RNA enzyme.
Vioque, A; Altman, S
1986-01-01
M1 RNA, the catalytic subunit of Escherichia coli RNase P, has been covalently linked at its 3' terminus to agarose beads. Unlike M1 RNA, which is active in solution in the absence of the protein component (C5) of RNase P, the RNA linked to the beads is active only in the presence of C5 protein. Affinity chromatography of crude extracts of E. coli on a column prepared from the beads to which the RNA has been crosslinked results in the purification of C5 protein in a single step. The protein h...
Analysis of affinely equivalent Boolean functions
Institute of Scientific and Technical Information of China (English)
MENG QingShu; ZHANG HuanGuo; YANG Min; WANG ZhangYi
2007-01-01
By some basic transforms and invariant theory, we give two results: 1) an algorithm,which can be used to judge if two Boolean functions are affinely equivalent and to obtain the equivalence relationship if they are equivalent. This is useful in studying Boolean functions and in engineering. For example, we classify all 8-variable homogeneous bent functions of degree 3 into two classes; 2) Reed-Muller codes R(4,6)/R(1,6), R(3,7)/R(1,7) are classified efficiently.
Affine Coherent States in Quantum Cosmology
Malkiewicz, Przemyslaw
2015-01-01
A brief summary of the application of coherent states in the examination of quantum dynamics of cosmological models is given. We discuss quantization maps, phase space probability distributions and semiclassical phase spaces. The implementation of coherent states based on the affine group resolves the hardest singularities, renders self-adjoint Hamiltonians without boundary conditions and provides a completely consistent semi-classical description of the involved quantum dynamics. We consider three examples: the closed Friedmann model, the anisotropic Bianchi Type I model and the deep quantum domain of the Bianchi Type IX model.
Latest European coelacanth shows Gondwanan affinities.
Cavin, Lionel; Forey, Peter L; Buffetaut, Eric; Tong, Haiyan
2005-06-22
The last European fossil occurrence of a coelacanth is from the Mid-Cretaceous of the English Chalk (Turonian, 90 million years ago). Here, we report the discovery of a coelacanth from Late Cretaceous non-marine rocks in southern France. It consists of a left angular bone showing structures that imply close phylogenetic affinities with some extinct Mawsoniidae. The closest relatives are otherwise known from Cretaceous continental deposits of southern continents and suggest that the dispersal of freshwater organisms from Africa to Europe occurred in the Late Cretaceous.
Tran, Steven; Nowicki, Magda; Facciol, Amanda; Chatterjee, Diptendu; Gerlai, Robert
2016-04-01
Zebrafish express enzymes that metabolize ethanol in a manner comparable to that of mammals, including humans. We previously demonstrated that acute ethanol exposure increases alcohol dehydrogenase (ADH) activity in an inverted U-shaped dose-dependent manner. It was hypothesized that the biphasic dose-response was due to the increased activity of a high-affinity ADH isoform following exposure to low concentrations of ethanol and increased activity of a low-affinity ADH isoform following exposure to higher concentrations of ethanol. To test this hypothesis, we exposed zebrafish to different concentrations of ethanol (0%, 0.25%, 0.5%, and 1.0% v/v) for 30 min and measured the total ADH activity in the zebrafish liver. However, we also repeated this enzyme activity assay using a low concentration of the substrate (ethanol) to determine the activity of high-affinity ADH isoforms. We found that total ADH activity in response to ethanol induces an inverted U-shaped dose-response similar to our previous study. Using a lower substrate level in our enzyme assay targeting high-affinity isozymes, we found a similar dose-response. However, the difference in activity between the high and low substrate assays (high substrate activity - low substrate activity), which provide an index of activity for low-affinity ADH isoforms, revealed no significant effect of ethanol exposure. Our results suggest that the inverted U-shaped dose-response for total ADH activity in response to ethanol is driven primarily by high-affinity isoforms of ADH.
Affine Fullerene C60 in a GS-Quasigroup
Directory of Open Access Journals (Sweden)
Vladimir Volenec
2014-01-01
Full Text Available It will be shown that the affine fullerene C60, which is defined as an affine image of buckminsterfullerene C60, can be obtained only by means of the golden section. The concept of the affine fullerene C60 will be constructed in a general GS-quasigroup using the statements about the relationships between affine regular pentagons and affine regular hexagons. The geometrical interpretation of all discovered relations in a general GS-quasigroup will be given in the GS-quasigroup C(1/2(1+5.
The perception of 3D shape from planar cut contours.
Egan, Eric J L; Todd, James T; Phillips, Flip
2011-10-01
A new computational analysis is described for estimating 3D shapes from orthographic images of surfaces that are textured with planar cut contours. For any given contour pattern, this model provides a family of possible interpretations that are all related by affine scaling and shearing transformations in depth, depending on the specific values of its free parameters that are used to compute the shape estimate. Two psychophysical experiments were performed in an effort to compare the model predictions with observers' judgments of 3D shape for developable and non-developable surfaces. The results reveal that observers' perceptions can be systematically distorted by affine scaling and shearing transformations in depth and that the magnitude and direction of these distortions vary systematically with the 3D orientations of the contour planes.
Stocker-Majd, Gisela; Hilbrig, Frank; Freitag, Ruth
2008-06-13
Affinity precipitation was compared to affinity chromatography and batch adsorption as the final purification step in a protocol for the isolation of haemoglobin from human blood. Haptoglobin was the affinity ligand. The first steps on the process were realized by traditional methods (lyses of red blood cells followed by ammonium sulphate precipitation). For affinity chromatography (and batch adsorption) the ligand was linked to Sepharose, for affinity precipitation to a thermoresponsive polymer, namely poly(N-isopropylacrylamide). Five haptoglobin-poly(N-isopropylacrylamide) bioconjugates (affinity macroligands) were constructed with different polymer: haptoglobin-coupling ratios. Conjugation of haptoglobin to the soluble poly(N-isopropylacrylamide) apparently does not change the interaction thermodynamics with haemoglobin, as the haemoglobin binding constants calculated by a Scatchard analysis for the affinity macroligand were of the same order of magnitude as those described in the literature for the haemoglobin-haptoglobin complex in solution. Two elution protocols were used for haemoglobin release from the various affinity materials, one at pH 2, the other with 5 M urea at pH 11. Both affinity chromatography and affinity precipitation yielded a pure haemoglobin of high quality. Compared to the affinity chromatography, affinity precipitation showed a significantly higher ligand efficiency (ratio of the experimental capacity to the theoretical one). The method thus makes better use of the expensive affinity ligands. As affinity precipitation only requires small temperature changes to bring about precipitation/redissolution of the affinity complexes and a centrifugation step for recovery of the precipitate, the method in addition has advantages in term of scalability and simplicity.
Spherical functions on affine Lie groups
Etingof, P; Kirillov, A A; Pavel Etingof; Igor Frenkel; Alexander Kirillov Jr
1994-01-01
We show that the space of holomorphic functions of a fixed degree on an affine Lie group which take values in a finite-dimensional representation of this group and are equivariant with respect to (twisted) conjugacy coin- cides with the space of conformal blocks of the Wess-Zumino-Witten conformal field theory on an elliptic curve with punctures, or, equivalently,with the space of states of the Chern-Simons topological field theory in genus 1. This provides a group-theoretic realization of the Segal modular functor for elliptic curves. We also show that the the radial part of the second order Laplace operator on an affine Lie group acting in the space of equivariant functions coincides with the operator defining the Knizhnik-Zamolodchikov connection on conformal blocks on elliptic curves, and its eigenfunctions coincide with the correlation functions of conformal blocks. At the critical value of the degree (minus the dual Coxeter number of the underlying simple Lie algebra) there exist higher order Laplace op...
Affine Mirkovi\\'c-Vilonen polytopes
Baumann, Pierre; Tingley, Peter
2011-01-01
Each integrable lowest weight representation of a symmetrizable Kac-Moody Lie algebra g has a crystal in the sense of Kashiwara, which describes its combinatorial properties. For a given g, there is a limit crystal, usually denoted by B(-\\infty), which contains all the other crystals. When g is finite dimensional, a convex polytope, called the Mirkovi\\'c-Vilonen polytope, can be associated to each element in B(-\\infty). This polytope sits in the dual space of a Cartan subalgebra of g, and its edges are parallel to the roots of g. In this paper, we generalize this construction to the case where g is a symmetric affine Kac-Moody algebra. The datum of the polytope must however be complemented by partitions attached to the edges parallel to the imaginary root \\delta. We prove that these decorated polytopes are characterized by conditions on their normal fans and on their 2-faces. In addition, we discuss how our polytopes provide an analog of the notion of Lusztig datum for affine Kac-Moody algebras. Our main tool...
Affine conformal vectors in space-time
Coley, A. A.; Tupper, B. O. J.
1992-05-01
All space-times admitting a proper affine conformal vector (ACV) are found. By using a theorem of Hall and da Costa, it is shown that such space-times either (i) admit a covariantly constant vector (timelike, spacelike, or null) and the ACV is the sum of a proper affine vector and a conformal Killing vector or (ii) the space-time is 2+2 decomposable, in which case it is shown that no ACV can exist (unless the space-time decomposes further). Furthermore, it is proved that all space-times admitting an ACV and a null covariantly constant vector (which are necessarily generalized pp-wave space-times) must have Ricci tensor of Segré type {2,(1,1)}. It follows that, among space-times admitting proper ACV, the Einstein static universe is the only perfect fluid space-time, there are no non-null Einstein-Maxwell space-times, and only the pp-wave space-times are representative of null Einstein-Maxwell solutions. Otherwise, the space-times can represent anisotropic fluids and viscous heat-conducting fluids, but only with restricted equations of state in each case.
Cyclage, catabolism, and the affine Hecke algebra
Blasiak, Jonah
2010-01-01
We identify a subalgebra \\pH_n of the extended affine Hecke algebra \\eH_n of type A. The subalgebra \\pH_n is a \\u-analogue of the monoid algebra of \\S_n \\ltimes \\ZZ_{\\geq 0}^n and inherits a canonical basis from that of \\eH_n. We show that its left cells are naturally labeled by tableaux filled with positive integer entries having distinct residues mod n, which we term \\emph{positive affine tableaux} (PAT). We then exhibit a cellular subquotient \\R_{1^n} of \\pH_n that is a \\u-analogue of the ring of coinvariants \\CC[y_1,...,y_n]/(e_1,...,e_n) with left cells labeled by PAT that are essentially standard Young tableaux with cocharge labels. Multiplying canonical basis elements by a certain element \\pi \\in \\pH_n corresponds to rotations of words, and on cells corresponds to cocyclage. We further show that \\R_{1^n} has cellular quotients \\R_\\lambda that are \\u-analogues of the Garsia-Procesi modules R_\\lambda with left cells labeled by (a PAT version of) the \\lambda-catabolizable tableaux. We give a conjectural d...
Affine Geometry, Visual Sensation, and Preference for Symmetry of Things in a Thing
Directory of Open Access Journals (Sweden)
Birgitta Dresp-Langley
2016-11-01
Full Text Available Evolution and geometry generate complexity in similar ways. Evolution drives natural selection while geometry may capture the logic of this selection and express it visually, in terms of specific generic properties representing some kind of advantage. Geometry is ideally suited for expressing the logic of evolutionary selection for symmetry, which is found in the shape curves of vein systems and other natural objects such as leaves, cell membranes, or tunnel systems built by ants. The topology and geometry of symmetry is controlled by numerical parameters, which act in analogy with a biological organism’s DNA. The introductory part of this paper reviews findings from experiments illustrating the critical role of two-dimensional (2D design parameters, affine geometry and shape symmetry for visual or tactile shape sensation and perception-based decision making in populations of experts and non-experts. It will be shown that 2D fractal symmetry, referred to herein as the “symmetry of things in a thing”, results from principles very similar to those of affine projection. Results from experiments on aesthetic and visual preference judgments in response to 2D fractal trees with varying degrees of asymmetry are presented. In a first experiment (psychophysical scaling procedure, non-expert observers had to rate (on a scale from 0 to 10 the perceived beauty of a random series of 2D fractal trees with varying degrees of fractal symmetry. In a second experiment (two-alternative forced choice procedure, they had to express their preference for one of two shapes from the series. The shape pairs were presented successively in random order. Results show that the smallest possible fractal deviation from “symmetry of things in a thing” significantly reduces the perceived attractiveness of such shapes. The potential of future studies where different levels of complexity of fractal patterns are weighed against different degrees of symmetry is pointed out
Aguda, Adeleke H; Lavallee, Vincent; Cheng, Ping; Bott, Tina M; Meimetis, Labros G; Law, Simon; Nguyen, Nham T; Williams, David E; Kaleta, Jadwiga; Villanueva, Ivan; Davies, Julian; Andersen, Raymond J; Brayer, Gary D; Brömme, Dieter
2016-08-26
Natural products are an important source of novel drug scaffolds. The highly variable and unpredictable timelines associated with isolating novel compounds and elucidating their structures have led to the demise of exploring natural product extract libraries in drug discovery programs. Here we introduce affinity crystallography as a new methodology that significantly shortens the time of the hit to active structure cycle in bioactive natural product discovery research. This affinity crystallography approach is illustrated by using semipure fractions of an actinomycetes culture extract to isolate and identify a cathepsin K inhibitor and to compare the outcome with the traditional assay-guided purification/structural analysis approach. The traditional approach resulted in the identification of the known inhibitor antipain (1) and its new but lower potency dehydration product 2, while the affinity crystallography approach led to the identification of a new high-affinity inhibitor named lichostatinal (3). The structure and potency of lichostatinal (3) was verified by total synthesis and kinetic characterization. To the best of our knowledge, this is the first example of isolating and characterizing a potent enzyme inhibitor from a partially purified crude natural product extract using a protein crystallographic approach.
Classical models of affinely-rigid bodies with "thickness" in degenerate dimension
Kovalchuk, Vasyl
2009-01-01
The special interest is devoted to such situations when the material space of our object with affine degrees of freedom has generally lower dimension than the one of the physical space. In other words when we have the $m$-dimensional affinely-rigid body moving in the $n$-dimensional physical space, $m
Real-time affine invariant gesture recognition for LED smart lighting control
Chen, Xu; Liao, Miao; Feng, Xiao-Fan
2015-03-01
Gesture recognition has attracted extensive research interest in the field of human computer interaction. Realtime affine invariant gesture recognition is an important and challenging problem. This paper presents a robust affine view invariant gesture recognition system for realtime LED smart light control. As far as we know, this is the first time that gesture recognition has been applied for control LED smart light in realtime. Employing skin detection, hand blobs captured from a top view camera are first localized and aligned. Subsequently, SVM classifiers trained on HOG features and robust shape features are then utilized for gesture recognition. By accurately recognizing two types of gestures ("gesture 8" and a "5 finger gesture"), a user is enabled to toggle lighting on/off efficiently and control light intensity on a continuous scale. In each case, gesture recognition is rotation- and translation-invariant. Extensive evaluations in an office setting demonstrate the effectiveness and robustness of the proposed gesture recognition algorithm.
DEFF Research Database (Denmark)
Prats, Miquel; Lim, Sungwoo; Jowers, Iestyn
2009-01-01
This paper is concerned with how design shapes are generated and explored by means of sketching. It presents research into the way designers transform shapes from one state to another using sketch representations. An experimental investigation of the sketching processes of designers is presented....... phenomenon of ‘subshape' and suggests that a computational mechanism for detecting sub-shapes in design sketches might augment explorative sketching by providing important opportunities for manipulating and generating shape in design....
Dynamic friction of self-affine surfaces
Schmittbuhl, Jean; Vilotte, Jean-Pierre; Roux, Stéphane
1994-02-01
We investigate the velocity dependence of the friction between two rigid blocks limited by a self-affine surface such as the one generated by a crack. The upper solid is subjected either to gravity or to an external elastic stiffness, and is driven horizontally at constant velocity, V, while the lower solid is fixed. For low velocities, the apparent friction coefficient is constant. For high velocities, the apparent friction is shown to display a velocity weakening. The weakening can be related to the variation of the mean contact time due to the occurrence of jumps during the motions. The cross-over between these two regimes corresponds to a characteristic velocity which depends on the geometry of the surfaces and on the mean normal force. In the case of simple gravity loading, the velocity dependence of the apparent friction at high velocities is proportional to 1/V^2 where V is the imposed tangential velocity. In the case of external elastic stiffness, two velocity weakening regimes can be identified, the first is identical to the gravity case with a 1/V^2 dependence, the second appears at higher velocities and is characterized by a 1/V variation. The characteristic velocity of this second cross-over depends on the roughness and the elastic stiffness. The statistical distribution of ballistic flight distances is analysed, and is shown to reveal in all cases the self-affinity of the contacting surfaces. Nous analysons la dépendence en vitesse du frottement entre deux solides limités par une surface rugueuse auto-affine comme celle d'une surface de fracture. Le solide supérieur est soumis soit à la gravité, soit à une raideur élastique externe, et est entraîné à vitesse horizontale constante V sur le solide inférieur fixe. A faible vitesse, le coefficient de friction apparent, est constant. A forte vitesse, le coefficient de friction apparent devient inversement proportionnel à la vitesse. Cette dépendance peut être reliée à la variation du temps
Data Stream Clustering With Affinity Propagation
Zhang, Xiangliang
2014-07-09
Data stream clustering provides insights into the underlying patterns of data flows. This paper focuses on selecting the best representatives from clusters of streaming data. There are two main challenges: how to cluster with the best representatives and how to handle the evolving patterns that are important characteristics of streaming data with dynamic distributions. We employ the Affinity Propagation (AP) algorithm presented in 2007 by Frey and Dueck for the first challenge, as it offers good guarantees of clustering optimality for selecting exemplars. The second challenging problem is solved by change detection. The presented StrAP algorithm combines AP with a statistical change point detection test; the clustering model is rebuilt whenever the test detects a change in the underlying data distribution. Besides the validation on two benchmark data sets, the presented algorithm is validated on a real-world application, monitoring the data flow of jobs submitted to the EGEE grid.
Affine and Projective Tree Metric Theorems
Harel, Matan; Pachter, Lior
2011-01-01
The tree metric theorem provides a combinatorial four point condition that characterizes dissimilarity maps derived from pairwise compatible split systems. A similar (but weaker) four point condition characterizes dissimilarity maps derived from circular split systems (Kalmanson metrics). The tree metric theorem was first discovered in the context of phylogenetics and forms the basis of many tree reconstruction algorithms, whereas Kalmanson metrics were first considered by computer scientists, and are notable in that they are a non-trivial class of metrics for which the traveling salesman problem is tractable. We present a unifying framework for these theorems based on combinatorial structures that are used for graph planarity testing. These are (projective) PC-trees, and their affine analogs, PQ-trees. In the projective case, we generalize a number of concepts from clustering theory, including hierarchies, pyramids, ultrametrics and Robinsonian matrices, and the theorems that relate them. As with tree metric...
Gravitational Goldstone fields from affine gauge theory
Tresguerres, R
2000-01-01
In order to facilitate the application of standard renormalization techniques, gravitation should be decribed, if possible, in pure connection formalism, as a Yang-Mills theory of a certain spacetime group, say the Poincare or the affine group. This embodies the translational as well as the linear connection. However, the coframe is not the standard Yang-Mills type gauge field of the translations, since it lacks the inhomogeneous gradient term in the gauge transformations. By explicitly restoring the "hidden" piece responsible for this behavior within the framework of nonlinear realizations, the usual geometrical interpretation of the dynamical theory becomes possible, and in addition one can avoid the metric or coframe degeneracy which would otherwise interfere with the integrations within the path integral. We claim that nonlinear realizations provide a general mathematical scheme clarifying the foundations of gauge theories of spacetime symmetries. When applied to construct the Yang-Mills theory of the aff...
Affine trajectory correction for nonholonomic mobile robots
Pham, Quang-Cuong
2011-01-01
Planning trajectories for nonholonomic systems is difficult and computationally expensive. When facing unexpected events, it may therefore be preferable to deform in some way the initially planned trajectory rather than to re-plan entirely a new one. We suggest here a method based on affine transformations to make such deformations. This method is exact and fast: the deformations and the resulting trajectories can be computed algebraically, in one step, and without any trajectory re-integration. To demonstrate the possibilities offered by this new method, we use it to derive position correction, orientation correction, obstacle avoidance and feedback control algorithms for the general class of planar wheeled robots and for a tridimensional underwater vehicle.
Affine connection form of Regge calculus
Khatsymovsky, V M
2015-01-01
Regge action is represented analogously to how the Palatini action for general relativity (GR) as some functional of the metric and a general connection as independent variables represents the Einstein-Hilbert action. The piecewise flat (or simplicial) spacetime of Regge calculus is equipped with some world coordinates and some piecewise affine metric which is completely defined by the set of edge lengths and the world coordinates of the vertices. The conjugate variables are the general nondegenerate matrices on the 3-simplices which play a role of a general discrete connection. Our previous result on some representation of the Regge calculus action in terms of the local Euclidean (Minkowsky) frame vectors and orthogonal connection matrices as independent variables is somewhat modified for the considered case of the general linear group GL(4,R) of the connection matrices. As a result, we have some action invariant w. r. t. arbitrary change of coordinates of the vertices (and related GL(4,R) transformations in...
Classical affine W-algebras associated to Lie superalgebras
Energy Technology Data Exchange (ETDEWEB)
Suh, Uhi Rinn, E-mail: uhrisu1@math.snu.ac.kr [Department of Mathematical Sciences, Seoul National University, GwanAkRo 1, Gwanak-Gu, Seoul 151-747 (Korea, Republic of)
2016-02-15
In this paper, we prove classical affine W-algebras associated to Lie superalgebras (W-superalgebras), which can be constructed in two different ways: via affine classical Hamiltonian reductions and via taking quasi-classical limits of quantum affine W-superalgebras. Also, we show that a classical finite W-superalgebra can be obtained by a Zhu algebra of a classical affine W-superalgebra. Using the definition by Hamiltonian reductions, we find free generators of a classical W-superalgebra associated to a minimal nilpotent. Moreover, we compute generators of the classical W-algebra associated to spo(2|3) and its principal nilpotent. In the last part of this paper, we introduce a generalization of classical affine W-superalgebras called classical affine fractional W-superalgebras. We show these have Poisson vertex algebra structures and find generators of a fractional W-superalgebra associated to a minimal nilpotent.
Directory of Open Access Journals (Sweden)
Jan Koenderink
2015-10-01
Full Text Available Local solid shape applies to the surface curvature of small surface patches—essentially regions of approximately constant curvatures—of volumetric objects that are smooth volumetric regions in Euclidean 3-space. This should be distinguished from local shape in pictorial space. The difference is categorical. Although local solid shape has naturally been explored in haptics, results in vision are not forthcoming. We describe a simple experiment in which observers judge shape quality and magnitude of cinematographic presentations. Without prior training, observers readily use continuous shape index and Casorati curvature scales with reasonable resolution.
DEFF Research Database (Denmark)
Winter, Pawel; Sterner, Henrik; Sterner, Peter
2009-01-01
We provide a unified description of (weighted) alpha shapes, beta shapes and the corresponding simplicialcomplexes. We discuss their applicability to various protein-related problems. We also discuss filtrations of alpha shapes and touch upon related persistence issues.We claim that the full...... potential of alpha-shapes and related geometrical constructs in protein-related problems yet remains to be realized and verified. We suggest parallel algorithms for (weighted) alpha shapes, and we argue that future use of filtrations and kinetic variants for larger proteins will need such implementation....
DEFF Research Database (Denmark)
Rasmussen, Majken Kirkegård; Pedersen, Esben Warming; Petersen, Marianne Graves;
2015-01-01
these shortcomings. We identify eight types of shape that are transformed in various ways to serve both functional and hedonic design purposes. Interaction with shape-changing interfaces is simple and rarely merges input and output. Three questions are discussed based on the review: (a) which design purposes may......Shape change is increasingly used in physical user interfaces, both as input and output. Yet, the progress made and the key research questions for shape-changing interfaces are rarely analyzed systematically. We review a sample of existing work on shape-changing interfaces to address...
Cani, Marie-Paule; Wyvill, Geoff
2008-01-01
Providing an intuitive modeling system, which would enable us to communicate about any free-form shape we have in mind at least as quickly as with real-world tools, is one of the main challenges of digital shape design. The user should ideally be able to create, deform, and progressively add details to a shape, without being aware of the underlying mathematical representation nor being tied by any constraint on the geometrical or topological nature of the model. This book presents the field of interactive shape design from this perspective. Since interactively creating a shape builds on the hu
Abacus models for parabolic quotients of affine Weyl groups
Hanusa, Christopher R H
2011-01-01
We introduce abacus diagrams that describe minimal length coset representatives in affine Weyl groups of types B, C, and D. These abacus diagrams use a realization of the affine Weyl group of type C due to Eriksson to generalize a construction of James for the symmetric group. We also describe several combinatorial models for these parabolic quotients that generalize classical results in affine type A related to core partitions.
Fast Affinity Propagation Clustering based on Machine Learning
Shailendra Kumar Shrivastava; J. L. Rana; DR.R.C.JAIN
2013-01-01
Affinity propagation (AP) was recently introduced as an un-supervised learning algorithm for exemplar based clustering. In this paper a novel Fast Affinity Propagation clustering Approach based on Machine Learning (FAPML) has been proposed. FAPML tries to put data points into clusters based on the history of the data points belonging to clusters in early stages. In FAPML we introduce affinity learning constant and dispersion constant which supervise the clustering process. FAPML also enforces...
Surfaces in 4-space from the affine differential geometry viewpoint
Luis Florial Espinoza Sánchez
2014-01-01
In this thesis, we study locally strictly convex surfaces from the affine differential viewpoint and generalize some tools for locally strictly submanifolds of codimension 2. We introduce a family of affine metrics on a locally strictly convex surface M in affine 4-space. Then, we define the symmetric and antisymmetric equiaffine planes associated with each metric. We show that if M is immersed in a locally atrictly convex hyperquadric, then the symmetric and the antisymmetric planes coincid...
Inhibition of Xanthine Oxidase Activity by Gnaphalium Affine Extract
Institute of Scientific and Technical Information of China (English)
Wei-qing Lin; Jian-xiang Xie; Xiao-mu Wu; Lin Yang; Hai-dong Wang
2014-01-01
Objective To evaluate the inhibitory effect of Gnaphalium affine extracts on xanthine oxidase (XO) activity in vitro and to analyze the mechanism of this effect. Methods In this in vitro study, Kinetic measurements were performed in 4 different inhibitor concentrations and 5 different xanthine concentrations (60, 100, 200, 300, 400 μmol/L). Dixon and Lineweaver-Burk plot analysis were used to determine Ki values and the inhibition mode for the compounds isolated from Gnaphalium affine extract. Results Four potent xanthine oxidase inhibitors were found in 95% ethanolic (v/v) Gnaphalium affine extract. Among them, the flavone Eupatilin exhibited the strongest inhibitory effect on XO with a inhibition constant (Ki) of 0.37μmol/L, lower than the Ki of allopurinol (4.56 mol/L), a known synthetic XO inhibitor. Apigenin (Ki of 0.56μmol/L, a proportion of 0.0053‰in Gnaphalium affine), luteolin (Ki of 2.63 μmol/L, 0.0032‰ in Gnaphalium affine) and 5-hydroxy-6,7,3’,4’-tetramethoxyflavone (Ki of 3.15μmol/L, 0.0043‰ in Gnaphalium affine) also contributed to the inhibitory effect of Gnaphalium affine extract on XO activity. Conclusions These results suggest that the use of Gnaphalium affine in the treatment of gout could be attributed to its inhibitory effect on XO. This study provides a rational basis for the traditional use of Gnaphalium affine against gout.
Maximum-Entropy Models of Sequenced Immune Repertoires Predict Antigen-Antibody Affinity
DEFF Research Database (Denmark)
Asti, Lorenzo; Uguzzoni, Guido; Marcatili, Paolo
2016-01-01
The immune system has developed a number of distinct complex mechanisms to shape and control the antibody repertoire. One of these mechanisms, the affinity maturation process, works in an evolutionary-like fashion: after binding to a foreign molecule, the antibody-producing B-cells exhibit a high...... of an HIV-1 infected patient. The Pearson correlation coefficient between our scoring function and the IC50 neutralization titer measured on 30 different antibodies of known sequence is as high as 0.77 (p-value 10-6), outperforming other sequence- and structure-based models....
Shaping the nonlinear near field
Wolf, Daniela; Schumacher, Thorsten; Lippitz, Markus
2016-01-01
Light scattering at plasmonic nanoparticles and their assemblies has led to a wealth of applications in metamaterials and nano-optics. Although shaping of fields around nanostructures is widely studied, the influence of the field inside the nanostructures is often overlooked. The linear field distribution inside the structure taken to the third power causes third-harmonic generation, a nonlinear optical response of matter. Here we demonstrate by a far field Fourier imaging method how this simple fact can be used to shape complex fields around a single particle alone. We employ this scheme to switch the third-harmonic emission from a single point source to two spatially separated but coherent sources, as in Young's double-slit assembly. We envision applications as diverse as coherently feeding antenna arrays and optical spectroscopy of spatially extended electronic states.
The cohomology of the affine Deligne-Lusztig varieties in the affine flag manifold of $GL_2$
Ivanov, Alexander
2009-01-01
This paper studies affine Deligne-Lusztig varieties in the affine flag manifold of GL_2. At first we determine all such varieties up to isomorphy. After this we investigate the representations of the sigma-stabilizer of an element b of the group on the etale cohomology of the affine Deligne-Lusztig variety X_w(b). We describe such representations as inductions from compact subgroups and in terms of noncuspidal representations.
Ahmed, Tofael; Zhang, Tiantao; Wang, Zhenying; He, Kanglai; Bai, Shuxiong
2017-02-01
The polyembryonic endoparasitoid wasp Macrocentrus cingulum Brischke (Hymenoptera: Braconidae) is deployed successfully as a biocontrol agent for corn pest insects from the Lepidopteran genus Ostrinia in Europe and throughout Asia, including Japan, Korea, and China. The odorants are recognized, bound, and solubilized by odorant-binding protein (OBP) in the initial biochemical recognition steps in olfaction that transport them across the sensillum lymph to initiate behavioral response. In the present study, we examine the odorant-binding effects on thermal stability of McinOBP2, McinOBP3, and their mutant form that lacks the third disulfide bonds. Real-time PCR experiments indicate that these two are expressed mainly in adult antennae, with expression levels differing by sex. Odorant-binding affinities of aldehydes, terpenoids, and aliphatic alcohols were measured with circular dichroism spectroscopy based on changes in the thermal stability of the proteins upon their affinities to odorants. The obtained results reveal higher affinity of trans-caryophelle, farnesene, and cis-3-Hexen-1-ol exhibits to both wild and mutant McinOBP2 and McinOBP3. Although conformational flexibility of the mutants and shape of binding cavity make differences in odorant affinity between the wild-type and mutant, it suggested that lacking the third disulfide bond in mutant proteins may have chance to incorrect folded structures that reduced the affinity to these odorants. In addition, CD spectra clearly indicate proteins enriched with α-helical content.
Directory of Open Access Journals (Sweden)
Jeerapond Leelawattanachai
Full Text Available The ability to use a systemically injected agent to image tumor is influenced by tumor characteristics such as permeability and vascularity, and the size, shape, and affinity of the imaging agent. In this study, six different imaging biomolecules, with or without specificity to tumor, were examined for tumor uptake and internalization at the whole body, ex-vivo tissue, and cellular levels: antibodies, antibody fragments (Fab, serum albumin, and streptavidin. The time of peak tumor uptake was dependent solely on the size of molecules, suggesting that molecular size is the major factor that influences tumor uptake by its effect on systemic clearance and diffusion into tumor. Affinity to tumor antigen failed to augment tumor uptake of Fab above non-specific accumulation, which suggests that Fab fragments of typical monoclonal antibodies may fall below an affinity threshold for use as molecular imaging agents. Despite abundant localization into the tumor, albumin and streptavidin were not found on cell surface or inside cells. By comparing biomolecules differing in size and affinity, our study highlights that while pharmacokinetics are a dominant factor in tumor uptake for biomolecules, affinity to tumor antigen is required for tumor binding and internalization.
Leelawattanachai, Jeerapond; Kwon, Keon-Woo; Michael, Praveesuda; Ting, Richard; Kim, Ju-Young; Jin, Moonsoo M
2015-01-01
The ability to use a systemically injected agent to image tumor is influenced by tumor characteristics such as permeability and vascularity, and the size, shape, and affinity of the imaging agent. In this study, six different imaging biomolecules, with or without specificity to tumor, were examined for tumor uptake and internalization at the whole body, ex-vivo tissue, and cellular levels: antibodies, antibody fragments (Fab), serum albumin, and streptavidin. The time of peak tumor uptake was dependent solely on the size of molecules, suggesting that molecular size is the major factor that influences tumor uptake by its effect on systemic clearance and diffusion into tumor. Affinity to tumor antigen failed to augment tumor uptake of Fab above non-specific accumulation, which suggests that Fab fragments of typical monoclonal antibodies may fall below an affinity threshold for use as molecular imaging agents. Despite abundant localization into the tumor, albumin and streptavidin were not found on cell surface or inside cells. By comparing biomolecules differing in size and affinity, our study highlights that while pharmacokinetics are a dominant factor in tumor uptake for biomolecules, affinity to tumor antigen is required for tumor binding and internalization.
Speech Enhancement Using Kernel and Normalized Kernel Affine Projection Algorithm
Directory of Open Access Journals (Sweden)
Bolimera Ravi
2013-08-01
Full Text Available The goal of this paper is to investigate the speech signal enhancement using Kernel Affine ProjectionAlgorithm (KAPA and Normalized KAPA. The removal of background noise is very important in manyapplications like speech recognition, telephone conversations, hearing aids, forensic, etc. Kernel adaptivefilters shown good performance for removal of noise. If the evaluation of background noise is more slowlythan the speech, i.e., noise signal is more stationary than the speech, we can easily estimate the noiseduring the pauses in speech. Otherwise it is more difficult to estimate the noise which results indegradation of speech. In order to improve the quality and intelligibility of speech, unlike time andfrequency domains, we can process the signal in new domain like Reproducing Kernel Hilbert Space(RKHS for high dimensional to yield more powerful nonlinear extensions. For experiments, we have usedthe database of noisy speech corpus (NOIZEUS. From the results, we observed the removal noise in RKHShas great performance in signal to noise ratio values in comparison with conventional adaptive filters.
Perspectives in shape analysis
Bruckstein, Alfred; Maragos, Petros; Wuhrer, Stefanie
2016-01-01
This book presents recent advances in the field of shape analysis. Written by experts in the fields of continuous-scale shape analysis, discrete shape analysis and sparsity, and numerical computing who hail from different communities, it provides a unique view of the topic from a broad range of perspectives. Over the last decade, it has become increasingly affordable to digitize shape information at high resolution. Yet analyzing and processing this data remains challenging because of the large amount of data involved, and because modern applications such as human-computer interaction require real-time processing. Meeting these challenges requires interdisciplinary approaches that combine concepts from a variety of research areas, including numerical computing, differential geometry, deformable shape modeling, sparse data representation, and machine learning. On the algorithmic side, many shape analysis tasks are modeled using partial differential equations, which can be solved using tools from the field of n...
Platelet affinity for burro aorta collagen
Energy Technology Data Exchange (ETDEWEB)
Schneider, M.D.
1977-10-01
Despite ingenious concepts, there are no unequivocal clues as to what, when, and how some undefined biochemical factor(s) or constituent(s) that localizes in the arterial wall can precipitate a thromboatheromatous lesion or arterial disease. The present study focused on the extraction, partial purification, and characterization of a collagen-active platelet stimulator from the aortas of aged burros. The aggregator moiety in the aorta extracts invariably had a higher affinity for platelets in citrated platelet-rich plasma of human beings than for platelets of homologous burros. The platelet-aggregating factor(s) in the aorta extract was retained by incubation with ..cap alpha..-chymotrypsin. Platelet-aggregating activity was rapidly abolished after incubation with collagenase, as determined by platelet-aggregometry tests. Evidence based on light microscope and polysaccharide histochemical reactions indicates a probability that the intracellular amorphous matrix (PAS-positive) and filamentous components (PTAH-positive) expelled from smooth muscle cells disrupted during homogenization of the aorta may be a principal source of a precursor collagen species which is a potent inducer of platelet aggregation.
Affine connection form of Regge calculus
Khatsymovsky, V. M.
2016-12-01
Regge action is represented analogously to how the Palatini action for general relativity (GR) as some functional of the metric and a general connection as independent variables represents the Einstein-Hilbert action. The piecewise flat (or simplicial) spacetime of Regge calculus is equipped with some world coordinates and some piecewise affine metric which is completely defined by the set of edge lengths and the world coordinates of the vertices. The conjugate variables are the general nondegenerate matrices on the three-simplices which play the role of a general discrete connection. Our previous result on some representation of the Regge calculus action in terms of the local Euclidean (Minkowsky) frame vectors and orthogonal connection matrices as independent variables is somewhat modified for the considered case of the general linear group GL(4, R) of the connection matrices. As a result, we have some action invariant w.r.t. arbitrary change of coordinates of the vertices (and related GL(4, R) transformations in the four-simplices). Excluding GL(4, R) connection from this action via the equations of motion we have exactly the Regge action for the considered spacetime.
Affinity of guanosine derivatives for polycytidylate revisited
Kanavarioti, A.; Hurley, T. B.; Baird, E. E.
1995-01-01
Evidence is presented for complexation of guanosine 5'-monophosphate 2-methylimidazolide (2-MeImpG) with polycytidylate (poly(C)) at pH 8.0 and 23 degrees C in the presence of 1.0 M NaCl2 and 0.2 M MgCl2 in water. The association of 2-MeImpG with poly(C) was investigated using UV-vis spectroscopy as well as by monitoring the kinetics of the nucleophilic substitution reaction of the imidazole moiety by amines. The results of both methods are consistent with moderately strong poly(C) 2-MeImpG complexation and the spectrophotometric measurements allowed the construction of a binding isotherm with a concentration of 2-MeImpG equal to 5.55 +/- 0.15 mM at half occupancy. UV spectroscopy was employed to establish the binding of other guanosine derivatives on poly(C). These derivatives are guanosine 5'-monophosphate (5'GMP), guanosine 5'-monophosphate imidazolide (ImpG), and guanosine 5'-monophosphate morpholidate (morpG). Within experimental error these guanosine derivatives exhibit the same affinity for poly(C) as 2-MeImpG.
Tillett, Jackie
2011-01-01
Politics is the process and method of decision making for individuals and groups. Politics may define the power relationships between women and their healthcare providers. Politics may shape the experience for the woman. Nurses and birthing women can learn to negotiate the politics and power relationships surrounding the birth experience.
Maximum-Entropy Models of Sequenced Immune Repertoires Predict Antigen-Antibody Affinity.
Directory of Open Access Journals (Sweden)
Lorenzo Asti
2016-04-01
Full Text Available The immune system has developed a number of distinct complex mechanisms to shape and control the antibody repertoire. One of these mechanisms, the affinity maturation process, works in an evolutionary-like fashion: after binding to a foreign molecule, the antibody-producing B-cells exhibit a high-frequency mutation rate in the genome region that codes for the antibody active site. Eventually, cells that produce antibodies with higher affinity for their cognate antigen are selected and clonally expanded. Here, we propose a new statistical approach based on maximum entropy modeling in which a scoring function related to the binding affinity of antibodies against a specific antigen is inferred from a sample of sequences of the immune repertoire of an individual. We use our inference strategy to infer a statistical model on a data set obtained by sequencing a fairly large portion of the immune repertoire of an HIV-1 infected patient. The Pearson correlation coefficient between our scoring function and the IC50 neutralization titer measured on 30 different antibodies of known sequence is as high as 0.77 (p-value 10-6, outperforming other sequence- and structure-based models.
Routes to improve binding capacities of affinity resins demonstrated for Protein A chromatography.
Müller, Egbert; Vajda, Judith
2016-05-15
Protein A chromatography is a well-established platform in downstream purification of monoclonal antibodies. Dynamic binding capacities are continuously increasing with almost every newly launched Protein A resin. Nevertheless, binding capacities of affinity chromatography resins cannot compete with binding capacities obtained with modern ion exchange media. Capacities of affinity resins are roughly 50% lower. High binding capacities of ion exchange media are supported by spacer technologies. In this article, we review existing spacer technologies of affinity chromatography resins. A yet known effective approach to increase the dynamic binding capacity of Protein A resins is oligomerization of the particular Protein A motifs. This resembles the tentacle technology used in ion exchange chromatography. Dynamic binding capacities of a hexameric ligand are roughly twice as high compared to capacities obtained with a tetrameric ligand. Further capacity increases up to 130mg/ml can be realized with the hexamer ligand, if the sodium phosphate buffer concentration is increased from 20 to 100mM. Equilibrium isotherms revealed a BET shape for the hexamer ligand at monoclonal antibody liquid phase concentrations higher than 9mg/ml. The apparent multilayer formation may be due to hydrophobic forces. Other quality attributes such as recovery, aggregate content, and overall purity of the captured monoclonal antibody are not affected.
Maximum-Entropy Models of Sequenced Immune Repertoires Predict Antigen-Antibody Affinity.
Asti, Lorenzo; Uguzzoni, Guido; Marcatili, Paolo; Pagnani, Andrea
2016-04-01
The immune system has developed a number of distinct complex mechanisms to shape and control the antibody repertoire. One of these mechanisms, the affinity maturation process, works in an evolutionary-like fashion: after binding to a foreign molecule, the antibody-producing B-cells exhibit a high-frequency mutation rate in the genome region that codes for the antibody active site. Eventually, cells that produce antibodies with higher affinity for their cognate antigen are selected and clonally expanded. Here, we propose a new statistical approach based on maximum entropy modeling in which a scoring function related to the binding affinity of antibodies against a specific antigen is inferred from a sample of sequences of the immune repertoire of an individual. We use our inference strategy to infer a statistical model on a data set obtained by sequencing a fairly large portion of the immune repertoire of an HIV-1 infected patient. The Pearson correlation coefficient between our scoring function and the IC50 neutralization titer measured on 30 different antibodies of known sequence is as high as 0.77 (p-value 10-6), outperforming other sequence- and structure-based models.
Microtubule affinity-regulating kinase 4: structure, function, and regulation.
Naz, Farha; Anjum, Farah; Islam, Asimul; Ahmad, Faizan; Hassan, Md Imtaiyaz
2013-11-01
MAP/Microtubule affinity-regulating kinase 4 (MARK4) belongs to the family of serine/threonine kinases that phosphorylate the microtubule-associated proteins (MAP) causing their detachment from the microtubules thereby increasing microtubule dynamics and facilitating cell division, cell cycle control, cell polarity determination, cell shape alterations, etc. The MARK4 gene encodes two alternatively spliced isoforms, L and S that differ in their C-terminal region. These isoforms are differentially regulated in human tissues including central nervous system. MARK4L is a 752-residue-long polypeptide that is divided into three distinct domains: (1) protein kinase domain (59-314), (2) ubiquitin-associated domain (322-369), and (3) kinase-associated domain (703-752) plus 54 residues (649-703) involved in the proper folding and function of the enzyme. In addition, residues 65-73 are considered to be the ATP-binding domain and Lys88 is considered as ATP-binding site. Asp181 has been proposed to be the active site of MARK4 that is activated by phosphorylation of Thr214 side chain. The isoform MARK4S is highly expressed in the normal brain and is presumably involved in neuronal differentiation. On the other hand, the isoform MARK4L is upregulated in hepatocarcinoma cells and gliomas suggesting its involvement in cell cycle. Several biological functions are also associated with MARK4 including microtubule bundle formation, nervous system development, and positive regulation of programmed cell death. Therefore, MARK4 is considered as the most suitable target for structure-based rational drug design. Our sequence, structure- and function-based analysis should be helpful for better understanding of mechanisms of regulation of microtubule dynamics and MARK4 associated diseases.
Downstream processing of polysaccharide degrading enzymes by affinity chromatography.
Somers, W.A.C.
1992-01-01
The objective of this study was the development of affinity matrices to isolate and purify a number of polysaccharide degrading enzymes and the application of these adsorbents in the large- scale purification of the enzymes from fermentation broths. Affinity adsorbents were developed for endo-polyga
Affine group formulation of the Standard Model coupled to gravity
Energy Technology Data Exchange (ETDEWEB)
Chou, Ching-Yi, E-mail: l2897107@mail.ncku.edu.tw [Department of Physics, National Cheng Kung University, Taiwan (China); Ita, Eyo, E-mail: ita@usna.edu [Department of Physics, US Naval Academy, Annapolis, MD (United States); Soo, Chopin, E-mail: cpsoo@mail.ncku.edu.tw [Department of Physics, National Cheng Kung University, Taiwan (China)
2014-04-15
In this work we apply the affine group formalism for four dimensional gravity of Lorentzian signature, which is based on Klauder’s affine algebraic program, to the formulation of the Hamiltonian constraint of the interaction of matter and all forces, including gravity with non-vanishing cosmological constant Λ, as an affine Lie algebra. We use the hermitian action of fermions coupled to gravitation and Yang–Mills theory to find the density weight one fermionic super-Hamiltonian constraint. This term, combined with the Yang–Mills and Higgs energy densities, are composed with York’s integrated time functional. The result, when combined with the imaginary part of the Chern–Simons functional Q, forms the affine commutation relation with the volume element V(x). Affine algebraic quantization of gravitation and matter on equal footing implies a fundamental uncertainty relation which is predicated upon a non-vanishing cosmological constant. -- Highlights: •Wheeler–DeWitt equation (WDW) quantized as affine algebra, realizing Klauder’s program. •WDW formulated for interaction of matter and all forces, including gravity, as affine algebra. •WDW features Hermitian generators in spite of fermionic content: Standard Model addressed. •Constructed a family of physical states for the full, coupled theory via affine coherent states. •Fundamental uncertainty relation, predicated on non-vanishing cosmological constant.
Germinal center reaction: antigen affinity and presentation explain it all.
Oropallo, Michael A; Cerutti, Andrea
2014-07-01
The selection and expansion of B cells undergoing affinity maturation in the germinal center is a hallmark of humoral immunity. A recent paper in Nature provides new insights into the relationships between the affinity of the immunoglobulin receptor for antigen, the ability of B cells to present antigen to T cells, and the processes of selection, mutation, and clonal expansion in the germinal center.
Self-affine roughness influence on redox reaction charge admittance
Palasantzas, G
2005-01-01
In this work we investigate the influence of self-affine electrode roughness on the admittance of redox reactions during facile charge transfer kinetics. The self-affine roughness is characterized by the rms roughness amplitude w, the correlation length xi and the roughness exponent H (0
Synthesis of tetracycline analogs and their bone affinities
Institute of Scientific and Technical Information of China (English)
Wen Cai Huang; Hu Zheng; Ling Ling Weng
2008-01-01
Tetracycline analogs were designed and synthesized and their bone affinities were tested on hydroxyapatite. The results showedthat the carbonyl-amide-enol structure in A ring and phenol-ketone structure in BCD ring may be responsible for tetracycline's highbone affinity and either A ring or BCD ring has a planar conformation is essential.
The Affine Complete Hypersurfaces of Constant Gauss-Kronecker Curvature
Institute of Scientific and Technical Information of China (English)
Bao Fu WANG
2009-01-01
Given a bounded convex domain Ω with C∞ boundary and a function φ∈ C∞ ( partial deriv Ω), Li-Simon-Chen can construct an Euclidean complete and W-complete convex hypersurface M with constant affine Gauss-Kronecker curvature, and they guess the M is also affine complete. In this paper, we give a confirmation answer.
Ordinary matter in nonlinear affine gauge theories of gravitation
Tiemblo, A; Tiemblo, A; Tresguerres, R
1994-01-01
We present a general framework to include ordinary fermionic matter in the metric--affine gauge theories of gravity. It is based on a nonlinear gauge realization of the affine group, with the Lorentz group as the classification subgroup of the matter and gravitational fields.
Striving for Empathy: Affinities, Alliances and Peer Sexuality Educators
Fields, Jessica; Copp, Martha
2015-01-01
Peer sexuality educators' accounts of their work reveal two approaches to empathy with their students: affinity and alliance. "Affinity-based empathy" rests on the idea that the more commonalities sexuality educators and students share (or perceive they share), the more they will be able to empathise with one another, while…
Isolation of bovine serum albumin from whey using affinity chromatography
Besselink, T.; Janssen, A.E.M.; Boom, R.M.
2015-01-01
The adsorption of bovine serum albumin (BSA) to a chromatography resin with immobilised llama antibody fragments as affinity ligands was investigated. The maximum adsorption capacity of the affinity resin was 21.6 mg mL-1 with a Langmuir equilibrium constant of 20.4 mg mg-1. Using packed bed chromat
SHP-1 phosphatase activity counteracts increased T cell receptor affinity.
Hebeisen, Michael; Baitsch, Lukas; Presotto, Danilo; Baumgaertner, Petra; Romero, Pedro; Michielin, Olivier; Speiser, Daniel E; Rufer, Nathalie
2013-03-01
Anti-self/tumor T cell function can be improved by increasing TCR-peptide MHC (pMHC) affinity within physiological limits, but paradoxically further increases (K(d) affinity for the tumor antigen HLA-A2/NY-ESO-1, we investigated the molecular mechanisms underlying this high-affinity-associated loss of function. As compared with cells expressing TCR affinities generating optimal function (K(d) = 5 to 1 μM), those with supraphysiological affinity (K(d) = 1 μM to 15 nM) showed impaired gene expression, signaling, and surface expression of activatory/costimulatory receptors. Preferential expression of the inhibitory receptor programmed cell death-1 (PD-1) was limited to T cells with the highest TCR affinity, correlating with full functional recovery upon PD-1 ligand 1 (PD-L1) blockade. In contrast, upregulation of the Src homology 2 domain-containing phosphatase 1 (SHP-1/PTPN6) was broad, with gradually enhanced expression in CD8(+) T cells with increasing TCR affinities. Consequently, pharmacological inhibition of SHP-1 with sodium stibogluconate augmented the function of all engineered T cells, and this correlated with the TCR affinity-dependent levels of SHP-1. These data highlight an unexpected and global role of SHP-1 in regulating CD8(+) T cell activation and responsiveness and support the development of therapies inhibiting protein tyrosine phosphatases to enhance T cell-mediated immunity.
Frame-independent mechanics:geometry on affine bundles
Grabowska, K.; Grabowski, J.; Urbanski, P.
2005-01-01
Main ideas of the differential geometry on affine bundles are presented. Affine counterparts of Lie algebroid and Poisson structures are introduced and discussed. The developed concepts are applied in a frame-independent formulation of the time-dependent and the Newtonian mechanics.
Convergence of generic infinite products of affine operators
Directory of Open Access Journals (Sweden)
S. Reich
1999-01-01
Full Text Available We establish several results concerning the asymptotic behavior of random infinite products of generic sequences of affine uniformly continuous operators on bounded closed convex subsets of a Banach space. In addition to weak ergodic theorems we also obtain convergence to a unique common fixed point and more generally, to an affine retraction.
High affinity retinoic acid receptor antagonists: analogs of AGN 193109.
Johnson, A T; Wang, L; Gillett, S J; Chandraratna, R A
1999-02-22
A series of high affinity retinoic acid receptor (RAR) antagonists were prepared based upon the known antagonist AGN 193109 (2). Introduction of various phenyl groups revealed a preference for substitution at the para-position relative to the meta-site. Antagonists with the highest affinities for the RARs possessed hydrophobic groups, however, the presence of polar functionality was also well tolerated.
Striving for Empathy: Affinities, Alliances and Peer Sexuality Educators
Fields, Jessica; Copp, Martha
2015-01-01
Peer sexuality educators' accounts of their work reveal two approaches to empathy with their students: affinity and alliance. "Affinity-based empathy" rests on the idea that the more commonalities sexuality educators and students share (or perceive they share), the more they will be able to empathise with one another, while…
Peptide Nucleic Acids Having Enhanced Binding Affinity and Sequence Specificity
DEFF Research Database (Denmark)
1998-01-01
A novel class of compounds, known as peptide nucleic acids, bind complementary DNA and RNA strands more strongly than a corresponding DNA strand, and exhibit increased sequence specificity and binding affinity. Methods of increasing binding affinity and sequence specificity of peptide nucleic aci...
Detection of protein-protein interactions using tandem affinity purification.
Goodfellow, Ian; Bailey, Dalan
2014-01-01
Tandem affinity purification (TAP) is an invaluable technique for identifying interaction partners for an affinity tagged bait protein. The approach relies on the fusion of dual tags to the bait before separate rounds of affinity purification and precipitation. Frequently two specific elution steps are also performed to increase the specificity of the overall technique. In the method detailed here, the two tags used are protein G and a short streptavidin binding peptide; however, many variations can be employed. In our example the tags are separated by a cleavable tobacco etch virus protease target sequence, allowing for specific elution after the first round of affinity purification. Proteins isolated after the final elution step in this process are concentrated before being identified by mass spectrometry. The use of dual affinity tags and specific elution in this technique dramatically increases both the specificity and stringency of the pull-downs, ensuring a low level of background nonspecific interactions.
Affinity Monolith-Integrated Microchips for Protein Purification and Concentration.
Gao, Changlu; Sun, Xiuhua; Wang, Huaixin; Qiao, Wei; Hu, Bo
2016-01-01
Affinity chromatography is a valuable method to purify and concentrate minute amount of proteins. Monoliths with epoxy groups for affinity immobilization were prepared by direct in-situ photopolymerization of glycidyl methacrylate and ethylene glycol dimethacrylate in porogenic solvents consisting of 1-dodecanol and cyclohexanol. By integrating affinity monoliths onto a microfluidic system, targeted biomolecules can be captured and retained on affinity column, while other biomolecules having no specific interactions toward the immobilized ligands flow through the microchannel. Therefore, proteins which remain on the affinity column are purified and concentrated, and then eluted by appropriate solutions and finally, separated by microchip capillary electrophoresis. This integrated microfluidic device has been applied to the purification and separation of specific proteins (FITC-labeled human serum albumin and IgG) in a mixture.
IMPLEMENTASI ENKRIPSI DEKRIPSI ALGORITMA AFFINE CIPHER BERBASIS ANDROID
Directory of Open Access Journals (Sweden)
Sasono Wibowo
2014-11-01
Full Text Available Perkembangan Teknologi Informasi yang cukup pesat khususnya dalam bidang komunikasi menjadikan komunikasi sangat mudah namun dalam implementasinya perlu adanya keamanan tentang informasi yang disampaikan. Dalam komunikasi antar orang pasti memiliki pembicaraan informasi yang bersifat privat atau orang lain tidak boleh tahu tentang pembicaraan yang terjadi. Diperlukannya keamanan untuk menjaga kerahasiaan informasi pada saat komunikasi. Masyarakat lebih sering menggunakan komunikasi dengan telepon seluler karena dinilai mudah dibawa dan tidak repot menggunakannya. Kriptografi yang biasa dikenal sebagai ilmu yang mempelajari bagaimana cara menyembunyikan pesan bisa diterapkan dalam aplikasi pada telepon seluler sebagai contoh smartphone android. Dengan mengimplementasikan algoritma affine cipher maka aplikasi yang akan dibuat bisa mengubah isi pesan yang ada dan dapat mengamankan informasi yang ada. Algoritma affine cipher merupakan perkembangan dari algoritma caesar dimana algoritma affine cipher menggunakan dua kunci. Dengan mengimplementasikan algoritma affine cipher ke dalam android maka diharapkan kita bisa menyimpan informasi dari siapapun tanpa terbaca. Kata Kunci : Kriptografi, Affine Cipher, android, Implementasi, Informasi
Duals of Affine Grassmann Codes and Their Relatives
DEFF Research Database (Denmark)
Beelen, P.; Ghorpade, S. R.; Hoholdt, T.
2012-01-01
Affine Grassmann codes are a variant of generalized Reed-Muller codes and are closely related to Grassmann codes. These codes were introduced in a recent work by Beelen Here, we consider, more generally, affine Grassmann codes of a given level. We explicitly determine the dual of an affine...... Grassmann code of any level and compute its minimum distance. Further, we ameliorate the results by Beelen concerning the automorphism group of affine Grassmann codes. Finally, we prove that affine Grassmann codes and their duals have the property that they are linear codes generated by their minimum......-weight codewords. This provides a clean analogue of a corresponding result for generalized Reed-Muller codes....
Fractal-Based Exponential Distribution of Urban Density and Self-Affine Fractal Forms of Cities
Chen, Yanguang
2016-01-01
Urban population density always follows the exponential distribution and can be described with Clark's model. Because of this, the spatial distribution of urban population used to be regarded as non-fractal pattern. However, Clark's model differs from the exponential function in mathematics because that urban population is distributed on the fractal support of landform and land-use form. By using mathematical transform and empirical evidence, we argue that there are self-affine scaling relations and local power laws behind the exponential distribution of urban density. The scale parameter of Clark's model indicating the characteristic radius of cities is not a real constant, but depends on the urban field we defined. So the exponential model suggests local fractal structure with two kinds of fractal parameters. The parameters can be used to characterize urban space filling, spatial correlation, self-affine properties, and self-organized evolution. The case study of the city of Hangzhou, China, is employed to ...
An Affine-Invariant Sampler for Exoplanet Fitting and Discovery in Radial Velocity Data
Hou, Fengji; Hogg, David W; Weare, Jonathan; Schwab, Christian
2011-01-01
Markov Chain Monte Carlo (MCMC) proves to be powerful for Bayesian inference and in particular for exoplanet radial velocity fitting because MCMC provides more statistical information and makes better use of data than common approaches like chi-square fitting. However, the non-linear density functions encountered in these problems can make MCMC time-consuming. In this paper, we apply an ensemble sampler respecting affine invariance to orbital parameter extraction from radial velocity data. The autocorrelation time of this sampler is approximately the same for all parameters and far smaller than Metropolis-Hastings, which means it requires many fewer function calls to produce the same number of independent samples. The affine-invariant sampler speeds up MCMC by hundreds of times compared with Metropolis-Hastings in the same computing situation. Besides being fast, the new sampler has only one free parameter, and it does not require tuning for good performance, which is important for automatization. This novel ...
Foight, Glenna Wink; Chen, T Scott; Richman, Daniel; Keating, Amy E
2017-01-01
Peptide reagents with high affinity or specificity for their target protein interaction partner are of utility for many important applications. Optimization of peptide binding by screening large libraries is a proven and powerful approach. Libraries designed to be enriched in peptide sequences that are predicted to have desired affinity or specificity characteristics are more likely to yield success than random mutagenesis. We present a library optimization method in which the choice of amino acids to encode at each peptide position can be guided by available experimental data or structure-based predictions. We discuss how to use analysis of predicted library performance to inform rounds of library design. Finally, we include protocols for more complex library design procedures that consider the chemical diversity of the amino acids at each peptide position and optimize a library score based on a user-specified input model.
Shape Effects on Jamming of Granular Materials
Farhadi, Somayeh
slow relaxation towards an unjammed state in ellipses is associated with the possibility of small and slow changes in their orientations, which then allow a more efficient packing. In order to study the stress fluctuations, we implement photoelastic properties of the particles. We are able to track the g 2 (a measure of local stress) of each particle throughout the entire experiment. Unlike disks, the power spectra of g2, P(ω), is not rate invariant for ellipses. In other words, all curves of RP(ω) vs. ω/R (where R is the shear rate) with different values of R, collapse to a single curve for disks, but not for ellipses. The rate invariance of spectra was previously studied for sheared spherical glass beads and semi-2D pentagonal particles. This is the first experimental work in which the fluctuations of granular systems composed of elongated particles is addressed. We have also studied the formation and destruction of stress avalanches during Couette shear in both systems of disks and ellipses. In particular, we introduce measures which characterize the size and shape of stress avalanches. Analysis of these measures shows that the build-up and release of stress in both systems of disks and ellipses have similar distributions which indicates that the deformation of particles in a Couette cell does not resemble stick-slip behavior. We also find that the build-up and release of stress is faster is larger avalanches. Cyclic isotropic compression is performed on semi-2D systems of bi-disperse disks and identical ellipses with aspect ratio 2, which are composed of photoelastic particles. In each compression cycle, the system is compressed with a total strain of 1.6% and then expanded to the initial state. After completion of each half cycle, the system is allowed to relax, then imaged by two synchronized cameras. The packing fraction, φ, of compressed states are chosen above the isotopic jamming point (point J). In both systems of disks and ellipses, we observed
Self-affine Multiplicity Fluctuation of Slow Particles in 16O-AgBr Collisions at 3.7 A GeV
Institute of Scientific and Technical Information of China (English)
LI Jun-Sheng; ZHANG Dong-Hai; LI Hui-Ling; LIU Fu-Hu
2009-01-01
We study the slow particles in 16O-AgBr collisions at 3.7A GeV in nuclear emulsion with the method of two-dimensioned factorial moments using the Hurst exponent. Our investigation revea/s the power law behaviour, exhibited in self-affine anedysis, better than that in self-similar analysis. This work shows a clear evidence of self-affine target fragmentation.
Chasing polys: Interdisciplinary affinity and its connection to physics identity
Scott, Tyler D.
This research is based on two motivations that merge by means of the frameworks of interdisciplinary affinity and physics identity. First, a goal of education is to develop interdisciplinary abilities in students' thinking and work. But an often ignored factor is students interests and beliefs about being interdisciplinary. Thus, this work develops and uses a framework called interdisciplinary affinity. It encompasses students interests in making connections across disciplines and their beliefs about their abilities to make those connections. The second motivation of this research is to better understand how to engage more students with physics. Physics identity describes how a student sees themselves in relation to physics. By understanding how physics identity is developed, researchers and educators can identify factors that increase interest and engagement in physics classrooms. Therefore, physics identity was used in conjunction with interdisciplinary affinity. Using a mixed methods approach, this research used quantitative data to identify the relationships interdisciplinary affinity has with physics identity and the physics classroom. These connections were explored in more detail using a case study of three students in a high school physics class. Results showed significant and positive relationships between interdisciplinary affinity and physics identity, including the individual interest and recognition components of identity. It also identified characteristics of physics classrooms that had a significant, positive relationship with interdisciplinary affinity. The qualitative case study highlighted the importance of student interest to the relationship between interdisciplinary affinity and physics identity. It also identified interest and mastery orientation as key to understanding the link between interdisciplinary affinity and the physics classroom. These results are a positive sign that by understanding interdisciplinary affinity and physics identity
Boudaoud, S.; Rix, H.; Meste, O.; Heneghan, C.; O'Brien, C.
2007-12-01
We present a technique called corrected integral shape averaging (CISA) for quantifying shape and shape differences in a set of signals. CISA can be used to account for signal differences which are purely due to affine time warping (jitter and dilation/compression), and hence provide access to intrinsic shape fluctuations. CISA can also be used to define a distance between shapes which has useful mathematical properties; a mean shape signal for a set of signals can be defined, which minimizes the sum of squared shape distances of the set from the mean. The CISA procedure also allows joint estimation of the affine time parameters. Numerical simulations are presented to support the algorithm for obtaining the CISA mean and parameters. Since CISA provides a well-defined shape distance, it can be used in shape clustering applications based on distance measures such as[InlineEquation not available: see fulltext.]-means. We present an application in which CISA shape clustering is applied to P-waves extracted from the electrocardiogram of subjects suffering from sleep apnea. The resulting shape clustering distinguishes ECG segments recorded during apnea from those recorded during normal breathing with a sensitivity of[InlineEquation not available: see fulltext.] and specificity of[InlineEquation not available: see fulltext.].
Directory of Open Access Journals (Sweden)
C. O'Brien
2007-01-01
Full Text Available We present a technique called corrected integral shape averaging (CISA for quantifying shape and shape differences in a set of signals. CISA can be used to account for signal differences which are purely due to affine time warping (jitter and dilation/compression, and hence provide access to intrinsic shape fluctuations. CISA can also be used to define a distance between shapes which has useful mathematical properties; a mean shape signal for a set of signals can be defined, which minimizes the sum of squared shape distances of the set from the mean. The CISA procedure also allows joint estimation of the affine time parameters. Numerical simulations are presented to support the algorithm for obtaining the CISA mean and parameters. Since CISA provides a well-defined shape distance, it can be used in shape clustering applications based on distance measures such as k-means. We present an application in which CISA shape clustering is applied to P-waves extracted from the electrocardiogram of subjects suffering from sleep apnea. The resulting shape clustering distinguishes ECG segments recorded during apnea from those recorded during normal breathing with a sensitivity of 81% and specificity of 84%.
Optimal affine-invariant matching: performance characterization
Costa, Mauro S.; Haralick, Robert M.; Shapiro, Linda G.
1992-04-01
The geometric hashing scheme proposed by Lamdan and Wolfson can be very efficient in a model-based matching system, not only in terms of the computational complexity involved, but also in terms of the simplicity of the method. In a recent paper, we discussed errors that can occur with this method due to quantization, stability, symmetry, and noise problems. These errors make the original geometric hashing technique unsuitable for use on the factory floor. Beginning with an explicit noise model, which the original Lamdan and Wolfson technique lacks, we derived an optimal approach that overcomes these problems. We showed that the results obtained with the new algorithm are clearly better than the results from the original method. This paper addresses the performance characterization of the geometric hashing technique, more specifically the affine-invariant point matching, applied to the problem of recognizing and determining the pose of sheet metal parts. The experiments indicate that with a model having 10 to 14 points, with 2 points of the model undetected and 10 extraneous points detected, and with the model points perturbed by Gaussian noise of standard deviation 3 (0.58 of range), the average amount of computation required to obtain an answer is equivalent to trying 11 of the possible three-point bases. The misdetection rate, measured by the percentage of correct bases matches that fail to verify, is 0.9. The percentage of incorrect bases that successfully produced a match that did verify (false alarm rate) is 13. And, finally, 2 of the experiments failed to find a correct match and verify it. Results for experiments with real images are also presented.
Affinity capillary electrophoresis: the theory of electromigration.
Dubský, Pavel; Dvořák, Martin; Ansorge, Martin
2016-12-01
We focus on the state-of-the-art theory of electromigration under single and multiple complexation equilibrium. Only 1:1 complexation stoichiometry is discussed because of its unique status in the field of affinity capillary electrophoresis (ACE). First, we summarize the formulas for the effective mobility in various ACE systems as they appeared since the pioneering days in 1992 up to the most recent theories till 2015. Disturbing phenomena that do not alter the mobility of the analyte directly but cause an unexpected peak broadening have been studied only recently and are also discussed in this paper. Second, we turn our attention to the viscosity effects in ACE. Change in the background electrolyte viscosity is unavoidable in ACE but numerous observations scattered throughout the literature have not been reviewed previously. This leads to an uncritical employment of correction factors that may or may not be appropriate in practice. Finally, we consider the ionic strength effects in ACE, too. Limitations of the current theories are also discussed and the tasks identified where open problems still prevail. Graphical Abstract A weak base (A) undergoes an acidic-basic equilibria (in blue) and migrates with an electrophoretic mobility of [Formula: see text]. Simultaneously, it interacts with a selector (sel) while the analyte-selector complex migrates with an electrophoretic mobility of [Formula: see text]. The strength of the interaction (in orange) is governed by the binding constant, K A , and the concentration of the selector, c sel . This all gives the analyte an effective mobility of [Formula: see text] and moves it out of the zero position (EOF; right top insert). The interaction of the positively charged analyte with the neutral selector slows down the analyte with increasing selector concentration (right bottom insert).
Convulsant bicuculline modifies CNS muscarinic receptor affinity
Directory of Open Access Journals (Sweden)
Rodríguez de Lores Arnaiz Georgina
2006-04-01
Full Text Available Abstract Background Previous work from this laboratory has shown that the administration of the convulsant drug 3-mercaptopropionic acid (MP, a GAD inhibitor, modifies not only GABA synthesis but also binding of the antagonist [3H]-quinuclidinyl benzilate ([3H]-QNB to central muscarinic receptors, an effect due to an increase in affinity without modifications in binding site number. The cholinergic system has been implicated in several experimental epilepsy models and the ability of acetylcholine to regulate neuronal excitability in the neocortex is well known. To study the potential relationship between GABAergic and cholinergic systems with seizure activity, we analyzed the muscarinic receptor after inducing seizure by bicuculline (BIC, known to antagonize the GABA-A postsynaptic receptor subtype. Results We analyzed binding of muscarinic antagonist [3H]-QNB to rat CNS membranes after i.p. administration of BIC at subconvulsant (1.0 mg/kg and convulsant (7.5 mg/kg doses. Subconvulsant BIC dose failed to develop seizures but produced binding alteration in the cerebellum and hippocampus with roughly 40% increase and 10% decrease, respectively. After convulsant BIC dose, which invariably led to generalized tonic-clonic seizures, binding increased 36% and 15% to cerebellar and striatal membranes respectively, but decreased 12% to hippocampal membranes. Kd value was accordingly modified: with the subconvulsant dose it decreased 27% in cerebellum whereas it increased 61% in hippocampus; with the convulsant dose, Kd value decreased 33% in cerebellum but increased 85% in hippocampus. No change in receptor number site was found, and Hill number was invariably close to unity. Conclusion Results indicate dissimilar central nervous system area susceptibility of muscarinic receptor to BIC. Ligand binding was modified not only by a convulsant BIC dose but also by a subconvulsant dose, indicating that changes are not attributable to the seizure process
Koenderink, Jan|info:eu-repo/dai/nl/070864543; van Doorn, A.J.; Wagemans, Johan
2015-01-01
Local solid shape applies to the surface curvature of small surface patches-essentially regions of approximately constant curvatures-of volumetric objects that are smooth volumetric regions in Euclidean 3-space. This should be distinguished from local shape in pictorial space. The difference is cate
Quasi-Bézier Curves with Shape Parameters
Directory of Open Access Journals (Sweden)
Jun Chen
2013-01-01
Full Text Available The universal form of univariate Quasi-Bézier basis functions with multiple shape parameters and a series of corresponding Quasi-Bézier curves were constructed step-by-step in this paper, using the method of undetermined coefficients. The series of Quasi-Bézier curves had geometric and affine invariability, convex hull property, symmetry, interpolation at the endpoints and tangent edges at the endpoints, and shape adjustability while maintaining the control points. Various existing Quasi-Bézier curves became special cases in the series. The obvious geometric significance of shape parameters made the adjustment of the geometrical shape easier for the designer. The numerical examples indicated that the algorithm was valid and can easily be applied.
The sodium ion affinities of asparagine, glutamine, histidine and arginine
Wang, Ping; Ohanessian, Gilles; Wesdemiotis, Chrys
2008-01-01
The sodium ion affinities of the amino acids Asn, Gln, His and Arg have been determined by experimental and computational approaches (for Asn, His and Arg). Na+-bound heterodimers with amino acid and peptide ligands (Pep1, Pep2) were produced by electrospray ionization. From the dissociation kinetics of these Pep1-Na+-Pep2 ions to Pep1-Na+ and Pep2-Na+, determined by collisionally activated dissociation, a ladder of relative affinities was constructed and subsequently converted to absolute affinities by anchoring the relative values to known Na+ affinities. The Na+ affinities of Asn, His and Arg, were calculated at the MP2(full)/6-311+G(2d,2p)//MP2/6-31G(d) level of ab initio theory. The resulting experimental and computed Na+ affinities are in excellent agreement with one another. These results, combined with those of our previous studies, yield the sodium ion affinities of 18 out of the 20 [alpha]-amino acids naturally occurring in peptides and proteins of living systems.
Tetrahydroprotoberberine alkaloids with dopamine and σ receptor affinity.
Gadhiya, Satishkumar; Madapa, Sudharshan; Kurtzman, Thomas; Alberts, Ian L; Ramsey, Steven; Pillarsetty, Nagavara-Kishore; Kalidindi, Teja; Harding, Wayne W
2016-05-01
Two series of analogues of the tetrahydroprotoberberine (THPB) alkaloid (±)-stepholidine that (a) contain various alkoxy substituents at the C10 position and, (b) were de-rigidified with respect to (±)-stepholidine, were synthesized and evaluated for affinity at dopamine and σ receptors in order to evaluate effects on D3 and σ2 receptor affinity and selectivity. Small n-alkoxy groups are best tolerated by D3 and σ2 receptors. Among all compounds tested, C10 methoxy and ethoxy analogues (10 and 11 respectively) displayed the highest affinity for σ2 receptors as well as σ2 versus σ1 selectivity and also showed the highest D3 receptor affinity. De-rigidification of stepholidine resulted in decreased affinity at all receptors evaluated; thus the tetracyclic THPB framework is advantageous for affinity at dopamine and σ receptors. Docking of the C10 analogues at the D3 receptor, suggest that an ionic interaction between the protonated nitrogen atom and Asp110, a H-bond interaction between the C2 phenol and Ser192, a H-bond interaction between the C10 phenol and Cys181 as well as hydrophobic interactions of the aryl rings to Phe106 and Phe345, are critical for high affinity of the compounds.
Directory of Open Access Journals (Sweden)
Kaba Dramane
2010-10-01
Full Text Available Abstract Background Landmark based geometric morphometrics (GM allows the quantitative comparison of organismal shapes. When applied to systematics, it is able to score shape changes which often are undetectable by traditional morphological studies and even by classical morphometric approaches. It has thus become a fast and low cost candidate to identify cryptic species. Due to inherent mathematical properties, shape variables derived from one set of coordinates cannot be compared with shape variables derived from another set. Raw coordinates which produce these shape variables could be used for data exchange, however they contain measurement error. The latter may represent a significant obstacle when the objective is to distinguish very similar species. Results We show here that a single user derived dataset produces much less classification error than a multiple one. The question then becomes how to circumvent the lack of exchangeability of shape variables while preserving a single user dataset. A solution to this question could lead to the creation of a relatively fast and inexpensive systematic tool adapted for the recognition of cryptic species. Conclusions To preserve both exchangeability of shape and a single user derived dataset, our suggestion is to create a free access bank of reference images from which one can produce raw coordinates and use them for comparison with external specimens. Thus, we propose an alternative geometric descriptive system that separates 2-D data gathering and analyzes.
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Compared with piezoelectric ceramics and magnetostrictive materials, the shape memory materials possess larger recoverable strain and recovery stress but slower response to external field. It is expected that the magneto-shape memory materials may develop considerable strain as well as rapid and precise shape control. Pseudoelasticity and shape memory effect (SME) resulted from martensitic transformation and its reverse transformation in shape memory materials were generally described. The requirements of appearing the shape memory effect in materials and the criteria for thermoelastic martensitic transformation were given. Some aspects concerning characteristics of martensitic transformation, and factors affecting SME in Ni-Ti, Cu-Zn-Al and Fe-Mn-Si based alloys as well as ZrO2 containing ceramics were briefly reviewed. Thermodynamic calculation of Ms temperature as function of grain size and parent ordering in Cu-Zn-Al was presented. The works on prediction of Ms in Fe-Mn-Si based alloys and in ZrO2-CeO2 were mentioned. Magnetic shape memory materials were briefly introduced.
Hyperbolically Shaped Centrifugal Compressor
Institute of Scientific and Technical Information of China (English)
Romuald Puzyrewski; Pawel Flaszy(n)ski
2003-01-01
Starting from the classical centrifugal compressor, cone shaped in meridional cross section, two modifications are considered on the basis of results from 2D and 3D flow models. The first modification is the change of the meridional cross section to hyperbolically shaped channel. The second modification, proposed on the basis of 2D axisymmetric solution, concerns the shape of blading. On the strength of this solution the blades are formed as 3D shaped blades, coinciding with the recent tendency in 3D designs. Two aims were considered for the change of meridional compressor shape. The first was to remove the separation zone which appears as the flow tums from axial to radial direction. The second aim is to uniformize the flow at exit of impeller. These two goals were considered within the frame of 2D axisymmetric model. Replacing the cone shaped compressor by a hyperbolically shaped one, the separation at the corner was removed. The disc and shroud shape of the compressor was chosen in the way which satisfies the condition of most uniform flow at the compressor exit. The uniformity of exit flow from the rotor can be considered as the factor which influences the performance of the diffuser following the rotor. In the 2D model a family of stream surfaces of S1 type is given in order to find S2 surfaces which may be identified with the midblade surfaces of compressor blading. A computation of 3D type has been performed in order to establish the relations between 2D and 3D models in the calculation of flow parameters. In the presented example the 2D model appears as the inverse model which leads to 3D shape of blading whereas the 3D model has been used for the direct solution. In the presented example the confrontation of two models, 2D and 3D, leads to a better understanding of the application of these models to the design procedure.
Affine structures and a tableau model for E_6 crystals
Jones, Brant
2009-01-01
We provide the unique affine crystal structure for type E_6^{(1)} Kirillov-Reshetikhin crystals corresponding to the multiples of fundamental weights s Lambda_1, s Lambda_2, and s Lambda_6 for all s \\geq 1 (in Bourbaki's labeling of the Dynkin nodes, where 2 is the adjoint node). Our methods introduce a generalized tableaux model for classical highest weight crystals of type E and use the order three automorphism of the affine E_6^{(1)} Dynkin diagram. In addition, we provide a conjecture for the affine crystal structure of type E_7^{(1)} Kirillov-Reshetikhin crystals corresponding to the adjoint node.
ODE/IM correspondence and modified affine Toda field equations
Ito, Katsushi
2014-01-01
We study the two-dimensional affine Toda field equations for affine Lie algebra $\\hat{\\mathfrak{g}}$ modified by a conformal transformation and the associated linear equations. In the conformal limit, the associated linear problem reduces to a (pseudo-)differential equation. For classical affine Lie algebra $\\hat{\\mathfrak{g}}$, we obtain a (pseudo-)differential equation corresponding to the Bethe equations for the Langlands dual of the Lie algebra $\\mathfrak{g}$, which were found by Dorey et al. in study of the ODE/IM correspondence.
Affinity Thresholds for Membrane Fusion Triggering by Viral Glycoproteins▿
Hasegawa, Kosei; Hu, Chunling; Nakamura, Takafumi; Marks, James D.; Russell, Stephen J.; Peng, Kah-Whye
2007-01-01
Enveloped viruses trigger membrane fusion to gain entry into cells. The receptor affinities of their attachment proteins vary greatly, from 10−4 M to 10−9 M, but the significance of this is unknown. Using six retargeted measles viruses that bind to Her-2/neu with a 5-log range in affinity, we show that receptor affinity has little impact on viral attachment but is nevertheless a key determinant of infectivity and intercellular fusion. For a given cell surface receptor density, there is an aff...
Volatility Components, Affine Restrictions and Non-Normal Innovations
DEFF Research Database (Denmark)
Christoffersen, Peter; Jacobs, Kris; Dorian, Christian;
Recent work by Engle and Lee (1999) shows that allowing for long-run and short-run components greatly enhances a GARCH model's ability fit daily equity return dynamics. Using the risk-neutralization in Duan (1995), we assess the option valuation performance of the Engle-Lee model and compare...... models to four conditionally non-normal versions. As in Hsieh and Ritchken (2005), we find that non-affine models dominate affine models both in terms of fitting return and in terms of option valuation. For the affine models we find strong evidence in favor of the component structure for both returns...
Moment-Based Method to Estimate Image Affine Transform
Institute of Scientific and Technical Information of China (English)
FENG Guo-rui; JIANG Ling-ge
2005-01-01
The estimation of affine transform is a crucial problem in the image recognition field. This paper resorted to some invariant properties under translation, rotation and scaling, and proposed a simple method to estimate the affine transform kernel of the two-dimensional gray image. Maps, applying to the original, produce some correlative points that can accurately reflect the affine transform feature of the image. Furthermore, unknown variables existing in the kernel of the transform are calculated. The whole scheme only refers to one-order moment,therefore, it has very good stability.
Santo, Loredana
2016-02-01
Recent advances in shape memory polymer (SMP) foam research are reviewed. The SMPs belong to a new class of smart polymers which can have interesting applications in microelectromechanical systems, actuators and biomedical devices. They can respond to specific external stimulus changing their configuration and then remember the original shape. In the form of foams, the shape memory behaviour can be enhanced because they generally have higher compressibility. Considering also the low weight, and recovery force, the SMP foams are expected to have great potential applications primarily in aerospace. This review highlights the recent progress in characterization, evaluation, and proposed applications of SMP foams mainly for aerospace applications.
Bertsch, G F
2016-01-01
Gerry Brown initiated some early studies on the coexistence of different nuclear shapes. The subject has continued to be of interest and is crucial for understanding nuclear fission. We now have a very good picture of the potential energy surface with respect to shape degrees of freedom in heavy nuclei, but the dynamics remain problematic. In contrast, the early studies on light nuclei were quite successful in describing the mixing between shapes. Perhaps a new approach in the spirit of the old calculations could better elucidate the character of the fission dynamics and explain phenomena that current theory does not model well.
Tatartchenko, Vitali A.
Crystals of specified shape and size (shaped crystals) with controlled crystal growth (SCG) defect and impurity structure have to be grown for the successful development of modern engineering. Since the 1950s many hundreds of papers and patents concerned with shaped growth have been published. In this chapter, we do not try to enumerate the successful applications of shaped growth to different materials but rather to carry out a fundamental physical and mathematical analysis of shaping as well as the peculiarities of shaped crystal structures. Four main techniques, based on which the lateral surface can be shaped without contact with the container walls, are analyzed: the Czochralski technique (CZT), the Verneuil technique (VT), the floating zone technique (FZT), and technique of pulling from shaper (TPS). Modifications of these techniques are analyzed as well. In all these techniques the shape of the melt meniscus is controlled by surface tension forces, i.e., capillary forces, and here they are classified as capillary shaping techniques (CST). We look for conditions under which the crystal growth process in each CST is dynamically stable. Only in this case are all perturbations attenuated and a crystal of constant cross section shaping technique (CST) grown without any special regulation. The dynamic stability theory of the crystal growth process for all CST is developed on the basis of Lyapunov's dynamic stability theory. Lyapunov's equations for the crystal growth processes follow from fundamental laws. The results of the theory allow the choice of stable regimes for crystal growth by all CST as well as special designs of shapers in TPS. SCG experiments by CZT, VT, and FZT are discussed but the main consideration is given to TPS. Shapers not only allow crystal of very complicated cross section to be grown but provide a special distribution of impurities. A history of TPS is provided later in the chapter, because it can only be described after explanation of the
Shaping Crystals using Electrophoresis
Palacci, Jeremie; Mackiewicz, Kristian
2016-11-01
Electrophoresis is size and shape independent as stressed by Morrison in his seminal paper. Here we present an original approach to reshape colloidal crystals using an electric field as a carving tool.
Shape memory polyurethane foams
Directory of Open Access Journals (Sweden)
B. K. Kim
2012-01-01
Full Text Available Molded flexible polyurethane (PU foams have been synthesized from polypropylene glycol (PPG with different molecular weights (Mw and functionalities (f, and 2,4/2,6-toluene diisocyanate (TDI-80 with water as blowing agent. It was found that the glassy state properties of the foam mainly depended on the urethane group content while the rubbery state properties on the crosslink density. That is, PPG of low MW and low f (more urethane groups provided superior glass state modulus, strength, density, shape fixity and glass transition temperature (Tg, while that of high Mw and high f (higher crosslink density showed high rubbery modulus and shape recovery. Consequently shape fixity of low Mw PPG decreased from 85 to 72% while shape recovery increased from 52 to 63% as the content of high Mw PPG increased from 0 to 40%.
Reinforced Airfoil Shaped Body
DEFF Research Database (Denmark)
2011-01-01
The present invention relates to an airfoil shaped body with a leading edge and a trailing edge extending along the longitudinal extension of the body and defining a profile chord, the airfoil shaped body comprising an airfoil shaped facing that forms the outer surface of the airfoil shaped body...... and surrounds an internal volume of the body, a distance member that is connected to the facing inside the body and extends from the facing and into the internal volume of the body, and at least one reinforcing member that operates in tension for reinforcing the facing against inward deflections...... and that is connected to the facing inside the internal volume of the body at the same side of the profile chord as the connection of the distance member to the facing and to the distance member at a distance from the facing....
Directory of Open Access Journals (Sweden)
Deexith Reddy
2016-07-01
Full Text Available Shape memory alloys (SMAs are metals that "remember" their original shapes. SMAs are useful for such things as actuators which are materials that "change shape, stiffness, position, natural frequency, and other mechanical characteristics in response to temperature or electromagnetic fields" The potential uses for SMAs especially as actuators have broadened the spectrum of many scientific fields. The study of the history and development of SMAs can provide an insight into a material involved in cutting-edge technology. The diverse applications for these metals have made them increasingly important and visible to the world. This paper presents the working of shape memory alloys , the phenomenon of super-elasticity and applications of these alloys.
Free-standing silicon carbide shapes are produced by passing a properly diluted stream of a reactant gas, for example methyltrichlorosilane, into a...reaction chamber housing a thin walled, hollow graphite body heated to 1300-1500C. After the graphite body is sufficiently coated with silicon carbide , the...graphite body is fired, converting the graphite to gaseous CO2 and CO and leaving a silicon carbide shaped article remaining.
2009-01-01
B lymphocytes producing high affinity antibodies (Abs) are critical for protection from extracellular pathogens, such as bacteria and parasites. The process by which high affinity B cells are selected during the immune response has never been elucidated. Though it has been shown that high affinity cells directly outcompete low affinity cells in the germinal center (GC)2, whether there are also intrinsic differences between these cells has not been addressed. It could be that higher affinity c...
Dirac equation in gauge and affine-metric gravitation theories
Giachetta, G
1995-01-01
We show that the covariant derivative of Dirac fermion fields in the presence of a general linear connection on a world manifold is universal for Einstein's, gauge and affine-metric gravitation theories.
Elective affinities and economic thought: 1870-1914
Directory of Open Access Journals (Sweden)
João Antônio de Paula
2006-01-01
Full Text Available This article seeks to demonstrate that the concept of "elective affinities" can be applied to the relations between economic thought, literature, and philosophy. Emphasis is given to Institutionalist thought, the German historical school, and neoclassical thought.
REFINABLE DISTRIBUTIONS SUPPORTED ON SELF-AFFINE TILES
Institute of Scientific and Technical Information of China (English)
DaiXinrong
2002-01-01
In this paper,some conditions which assure the compactly supported refinable distributions supported on a self-affine tile to be Lebesgue-Stieltjes measures or absolutely continuous measures with respect to Lebesgue-Stieltjes measures are given.
ASIFT: An Algorithm for Fully Affine Invariant Comparison
Directory of Open Access Journals (Sweden)
Guoshen Yu
2011-02-01
Full Text Available If a physical object has a smooth or piecewise smooth boundary, its images obtained by cameras in varying positions undergo smooth apparent deformations. These deformations are locally well approximated by affine transforms of the image plane. In consequence the solid object recognition problem has often been led back to the computation of affine invariant image local features. The similarity invariance (invariance to translation, rotation, and zoom is dealt with rigorously by the SIFT method The method illustrated and demonstrated in this work, Affine-SIFT (ASIFT, simulates a set of sample views of the initial images, obtainable by varying the two camera axis orientation parameters, namely the latitude and the longitude angles, which are not treated by the SIFT method. Then it applies the SIFT method itself to all images thus generated. Thus, ASIFT covers effectively all six parameters of the affine transform.
A thermodynamic approach to the affinity optimization of drug candidates.
Freire, Ernesto
2009-11-01
High throughput screening and other techniques commonly used to identify lead candidates for drug development usually yield compounds with binding affinities to their intended targets in the mid-micromolar range. The affinity of these molecules needs to be improved by several orders of magnitude before they become viable drug candidates. Traditionally, this task has been accomplished by establishing structure activity relationships to guide chemical modifications and improve the binding affinity of the compounds. As the binding affinity is a function of two quantities, the binding enthalpy and the binding entropy, it is evident that a more efficient optimization would be accomplished if both quantities were considered and improved simultaneously. Here, an optimization algorithm based upon enthalpic and entropic information generated by Isothermal Titration Calorimetry is presented.
Ambiguities in Determination Of Self-Affinity in the AE-index Time Series
Watkins, N W; Rhodes, C S; Rowlands, G
2001-01-01
The interaction between the Earth's magnetic field and the solar wind plasma results in a natural plasma confinement system which stores energy. Dissipation of this energy through Joule heating in the ionosphere can be studied via the Auroral Electrojet (AE) index. The apparent broken power law form of the frequency spectrum of this index has motivated investigation of whether it can be described as fractal coloured noise. One frequently-applied test for self-affinity is to demonstrate linear scaling of the logarithm of the structure function of a time series with the logarithm of the dilation factor $\\lambda$. We point out that, while this is conclusive when applied to signals that are self-affine over many decades in $\\lambda$, such as Brownian motion, the slope deviates from exact linearity and the conclusions become ambiguous when the test is used over shorter ranges of $\\lambda$. We demonstrate that non self-affine time series made up of random pulses can show near-linear scaling over a finite dynamic ra...
Some Inequalities for Lp-mixed Affine Surface Area
Institute of Scientific and Technical Information of China (English)
ZHU Xian-yang
2012-01-01
In this paper,the concepts of the ith Lp-mixed affine surface area and Lp-polar curvature images are introduced,some new inequalities connecting these new notions with Lp-centroid bodies and p-Blaschke bodies are showed.Moreover,a Blaschke-Santaló type inequality for Lp-mixed affine surface area is established.Our results also imply the similar to the inequalities for Marcus-Lopes,Bergstrom and Ky Fan.
Affinity purification of sequence-specific DNA binding proteins.
1986-01-01
We describe a method for affinity purification of sequence-specific DNA binding proteins that is fast and effective. Complementary chemically synthesized oligodeoxynucleotides that contain a recognition site for a sequence-specific DNA binding protein are annealed and ligated to give oligomers. This DNA is then covalently coupled to Sepharose CL-2B with cyanogen bromide to yield the affinity resin. A partially purified protein fraction is combined with competitor DNA and subsequently passed t...
Affine A(1)3 N = 2 Monopole as the D Module and Affine ADHMN Sheaf
Institute of Scientific and Technical Information of China (English)
SONG Xiao-Shu; HOU Bo-Yu; GUO Yun-Dong; HOU Bo-Yuan; LING-HU Rong-Feng; L(U) Bing; CHENG Xin-Lu; YANG Xiang-Dong
2008-01-01
A Higgs-Yang-Mills monopole scattering spherical symmetrically Mong light cones is given. The left incoming anti-self-dual α plane fields are holomorphic, but the right outgoing SD fl plane fields are antiholomorphic, meanwhile the diffeomorphism symmetry is preserved with mutual inverse a/fine rapidity parameters μ and μ-1. The Dirac wave function scattering in this background also factorized respectively into the (anti)holomorphic amplitudes. The holomorphic anomaly is realized by the center term of a quasi Hopf algebra corresponding to an integrable conformal a/fine massive field. We find explicit Nahm transformation matrix (Fourier-Mukai transformation) between the Higgs YM BPS (fiat) bundles (D modules) and the affinized blow up ADHMN twistors (perverse sheafs). Thus we establish the algebra for the 't Hooft Hecke operators in the Hecke correspondence of the geometric Langfands program.
Shapes of interacting RNA complexes
DEFF Research Database (Denmark)
Fu, Benjamin Mingming; Reidys, Christian
2014-01-01
Shapes of interacting RNA complexes are studied using a filtration via their topological genus. A shape of an RNA complex is obtained by (iteratively) collapsing stacks and eliminating hairpin loops.This shape-projection preserves the topological core of the RNA complex and for fixed topological...... genus there are only finitely many such shapes. Our main result is a new bijection that relates the shapes of RNA complexes with shapes of RNA structures. This allows to compute the shape polynomial of RNA complexes via the shape polynomial of RNA structures. We furthermore present a linear time uniform...... sampling algorithm for shapes of RNA complexes of fixed topological genus....
Signatures of the self-affinity of fracture and faulting in pre-seismic electromagnetic emissions
Directory of Open Access Journals (Sweden)
S. M. Potirakis
2014-04-01
Full Text Available Of particular interest is the detection of precursors of an impending rupture. Theoretical, numerical studies along with laboratory experiments indicate that precursory signs of an impending failure are the sudden drop of fractal dimension and entropy, along with the anticorrelated, for large system sizes, rising of Hurst exponent and drop of a frequency–size power-law scaling exponent. Based on the widely accepted concept of the self-affine nature of faulting and fracture, we examine whether these precursory signs exist in the fracto-electromagnetic emissions resulting from the activation of a single fault.
Signatures of the self-affinity of fracture and faulting in pre-seismic electromagnetic emissions
Potirakis, S M; Kopanas, J; Antonopoulos, G
2012-01-01
Of particular interest is the detection of precursors of an impending rupture. Theoretical, numerical studies along with laboratory experiments indicate that precursory signs of an impending failure are the sudden drop of fractal dimension and entropy, along with the anticorrelated, for large system sizes, rising of Hurst exponent and drop of a frequency-size power-law scaling exponent. Based on the widely accepted concept of the self-affine nature of faulting and fracture, we examine whether these precursory signs exist in the fracto-electromagnetic emissions resulting from the activation of a single fault.
CaRuby-Nano: a novel high affinity calcium probe for dual color imaging.
Collot, Mayeul; Wilms, Christian D; Bentkhayet, Asma; Marcaggi, Païkan; Couchman, Kiri; Charpak, Serge; Dieudonné, Stéphane; Häusser, Michael; Feltz, Anne; Mallet, Jean-Maurice
2015-03-31
The great demand for long-wavelength and high signal-to-noise Ca(2+) indicators has led us to develop CaRuby-Nano, a new functionalizable red calcium indicator with nanomolar affinity for use in cell biology and neuroscience research. In addition, we generated CaRuby-Nano dextran conjugates and an AM-ester variant for bulk loading of tissue. We tested the new indicator using in vitro and in vivo experiments demonstrating the high sensitivity of CaRuby-Nano as well as its power in dual color imaging experiments.
Affinity Solvents for Intensified Organics Extraction: Development Challenges and Prospects
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
In most organics extraction processes, the commonly used solvents employ solely physical interactions. Therefore, for the recovery and purification of products from complex mixtures, the selectivity and/or capacity of classical solvents towards the desired solutes is usually insufficient, enforcing the need for complex and thus expensive separation schemes. Significant simplification and cost-reduction can be achieved when affinity solvents would be available that are able to recognize the solutes of interest by their molecular structure. The main development challenges to establish such affinity solvents are: Selection and incorporation of molecular recognition and complexation capabilities; Evaluation of extraction capabilities; Efficient recovery and recycling of the affinity solvents; Implementation in industrial extraction equipment. This paper presents how these development challenges are addressed at the University of Twente, going all the way from affinity solvent design and synthesis, via high throughput screening and characterization up to pilot plant evaluation. Essential in the successful development of affinity solvents are structural cooperations with molecular chemists and custom synthesis companies for their design and synthesis. The various aspects are illustrated by several examples where newly developed environmentally benign affinity solvents appeared able to create major breakthroughs. The applications addressed involve oxygenates, sugars, and pharmaceutical ingredients, such as optical isomers and biomolecules.
High affinity ligands for 'diazepam-insensitive' benzodiazepine receptors.
Wong, G; Skolnick, P
1992-01-14
Structurally diverse compounds have been shown to possess high affinities for benzodiazepine receptors in their 'diazepam-sensitive' (DS) conformations. In contrast, only the imidazobenzodiazepinone Ro 15-4513 has been shown to exhibit a high affinity for the 'diazepam-insensitive' (DI) conformation of benzodiazepine receptors. We examined a series of 1,4-diazepines containing one or more annelated ring systems for their affinities at DI and DS benzodiazepine receptors, several 1,4-diazepinone carboxylates including Ro 19-4603, Ro 16-6028 and Ro 15-3505 were found to possess high affinities (Ki approximately 2.6-20 nM) for DI. Nonetheless, among the ligands examined, Ro 15-4513 was the only substance with a DI/DS potency ratio approximately 1; other substances had ratios ranging from 13 to greater than 1000. Ligands with high to moderate affinities at DI were previously classified as partial agonists, antagonists, or partial inverse agonists at DS benzodiazepine receptors, but behaved as 'GABA neutral' (antagonist) substances at DI. The identification of several additional high affinity ligands at DI benzodiazepine receptors may be helpful in elucidating the pharmacological and physiological importance of these sites.
Institute of Scientific and Technical Information of China (English)
李惠杰
2014-01-01
This paper analyzes the induced voltage of V-shaped skylight of overhead contact system in China’s double electrified railway sections in power cut operation influencing the operation safety, explains that the induced voltage in the operation on V-shaped skylight will probably pose a threat to the personal safety of maintenance personnel, and puts forward some feasible measures for preventing the electric shock caused by the induced voltage, providing the reference for the safe operation and maintenance of tractive power supply system.%对我国双线电气化铁道区段接触网V形天窗停电作业中影响作业安全的感应电压进行了分析，说明在V形天窗作业时感应电压对检修人员的人身安全构成威胁，提出了可行的预防感应电压触电事故的措施，为牵引供电系统安全运行和维护提供了借鉴。
ICI Alleviation in OFDM System Utilizing Scale Alpha Pulse Shaping
Directory of Open Access Journals (Sweden)
Nor Adibah Ibrahim
2015-05-01
Full Text Available In this study, a new pulse shaping method namely scale alpha is proposed for mitigating Inter-Carrier Interference (ICI effect in Orthogonal Frequency-Division Multiplexing (OFDM system. The suggested pulse shape is designed and simulated using MATLAB software. Results show that the new pulse shape has lower ICI power and better impulse response performance than Franks, raised cosine and double-jump pulses.
DEFF Research Database (Denmark)
Adler-Nissen, Rebecca; Pouliot, Vincent
2014-01-01
. In this article we develop a framework to grasp the concrete workings of power in international politics. The notion of “emergent power” bridges two different understandings of power: as capability or relation. Emergent power refers to the generation and deployment of endogenous resources – social skills......How does power work in practice? Much of the “stuff” that state agents and other international actors do, on an everyday basis, remains impenetrable to existing IR theory. This is unfortunate, as the everyday performance of international practices actually helps shape world policy outcomes...
Directory of Open Access Journals (Sweden)
MIROSLAV KUZMANOVIC
2005-09-01
Full Text Available The current of a U-shaped argon stabilised DC arc was square modulated with a 40 Hz repetition frequency between 6 and 3 A. The delayed line intensity responses to the modulation of the arc current were investigated using calcium as a representative analyte. The intensities of both the atomic and ionic lines were monitored at different distances from the arc axis in the presence of various concentrations of the easily ionised element. Temporal evolutions were monitored on a millisecond time scale. It was found that the responses of the line intesity to the arc current change strongly depended on the observed radial position, especially in the vicinity of the arc axis. The obtained results showed a significant influence of even small amounts of the easily ionised element on the excitation and transport of the analyte and indicated a way of possibly improving the analytical capabilities of the excitation source.
Taking Stock as Theories of Word Learning Take Shape
Booth, Amy E.; Waxman, Sandra R.
2008-01-01
In this paper we consider the perceptual and conceptual contributions that shape early word learning, using research on the "shape bias" as a case in point. In our view, conceptual, linguistic, social-pragmatic, and perceptual sources of information influence one another powerfully and continuously in the service of word learning throughout…
Oligocrystalline shape memory alloys
Energy Technology Data Exchange (ETDEWEB)
Ueland, Stian M.; Chen, Ying; Schuh, Christopher A. [Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)
2012-05-23
Copper-based shape memory alloys (SMAs) exhibit excellent shape memory properties in single crystalline form. However, when they are polycrystalline, their shape memory properties are severely compromised by brittle fracture arising from transformation strain incompatibility at grain boundaries and triple junctions. Oligocrystalline shape memory alloys (oSMAs) are microstructurally designed SMA structures in which the total surface area exceeds the total grain boundary area, and triple junctions can even be completely absent. Here it is shown how an oligocrystalline structure provides a means of achieving single crystal-like SMA properties without being limited by constraints of single crystal processing. Additionally, the formation of oSMAs typically involves the reduction of the size scale of specimens, and sample size effects begin to emerge. Recent findings on a size effect on the martensitic transformation in oSMAs are compared and a new regime of heat transfer associated with the transformation heat evolution in these alloys is discussed. New results on unassisted two-way shape memory and the effect of loading rate in oSMAs are also reported. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Gomes, Henrique
2011-01-01
This thesis consists of two parts, connected by one central theme: the dynamics of the "shape of space". The first part of the thesis concerns the construction of a theory of gravity dynamically equivalent to general relativity (GR) in 3+1 form (ADM). What is special about this theory is that it does not possess foliation invariance, as does ADM. It replaces that "symmetry" by another: local conformal invariance. In so doing it more accurately reflects a theory of the "shape of space", giving us reason to call it \\emph{shape dynamics} (SD). In the first part we will try to present some of the highlights of results so far, and indicate what we can and cannot do with shape dynamics. Because this is a young, rapidly moving field, we have necessarily left out some interesting new results which are not yet in print and were developed alongside the writing of the thesis. The second part of the thesis will develop a gauge theory for "shape of space"--theories. To be more precise, if one admits that the physically re...
Shape memory polymer medical device
Maitland, Duncan; Benett, William J.; Bearinger, Jane P.; Wilson, Thomas S.; Small, IV, Ward; Schumann, Daniel L.; Jensen, Wayne A.; Ortega, Jason M.; Marion, III, John E.; Loge, Jeffrey M.
2010-06-29
A system for removing matter from a conduit. The system includes the steps of passing a transport vehicle and a shape memory polymer material through the conduit, transmitting energy to the shape memory polymer material for moving the shape memory polymer material from a first shape to a second and different shape, and withdrawing the transport vehicle and the shape memory polymer material through the conduit carrying the matter.
A Note on Primitive Permutation Groups of Prime Power Degree
Qian Cai; Hua Zhang
2015-01-01
Primitive permutation groups of prime power degree are known to be affine type, almost simple type, and product action type. At the present stage finding an explicit classification of primitive groups of affine type seems untractable, while the product action type can usually be reduced to almost simple type. In this paper, we present a short survey of the development of primitive groups of prime power degree, together with a brief description on such groups.
Locating irregularly shaped clusters of infection intensity
Directory of Open Access Journals (Sweden)
Niko Yiannakoulias
2010-05-01
Full Text Available Patterns of disease may take on irregular geographic shapes, especially when features of the physical environment influence risk. Identifying these patterns can be important for planning, and also identifying new environmental or social factors associated with high or low risk of illness. Until recently, cluster detection methods were limited in their ability to detect irregular spatial patterns, and limited to finding clusters that were roughly circular in shape. This approach has less power to detect irregularly-shaped, yet important spatial anomalies, particularly at high spatial resolutions. We employ a new method of finding irregularly-shaped spatial clusters at micro-geographical scales using both simulated and real data on Schistosoma mansoni and hookworm infection intensities. This method, which we refer to as the “greedy growth scan”, is a modification of the spatial scan method for cluster detection. Real data are based on samples of hookworm and S. mansoni from Kitengei, Makueni district, Kenya. Our analysis of simulated data shows how methods able to find irregular shapes are more likely to identify clusters along rivers than methods constrained to fixed geometries. Our analysis of infection intensity identifies two small areas within the study region in which infection intensity is elevated, possibly due to local features of the physical or social environment. Collectively, our results show that the “greedy growth scan” is a suitable method for exploratory geographical analysis of infection intensity data when irregular shapes are suspected, especially at micro-geographical scales.
Directory of Open Access Journals (Sweden)
Oswin Aichholzer
2014-05-01
Full Text Available Can folding a piece of paper flat make it larger? We explore whether a shape S must be scaled to cover a flat-folded copy of itself. We consider both single folds and arbitrary folds (continuous piecewise isometries \\(S\\to\\mathbb{R}^2\\. The underlying problem is motivated by computational origami, and is related to other covering and fixturing problems, such as Lebesgue's universal cover problem and force closure grasps. In addition to considering special shapes (squares, equilateral triangles, polygons and disks, we give upper and lower bounds on scale factors for single folds of convex objects and arbitrary folds of simply connected objects.
Xing, Fuyong; Yang, Lin
2015-10-01
Efficient and effective cell segmentation of neuroendocrine tumor (NET) in whole slide scanned images is a difficult task due to a large number of cells. The weak or misleading cell boundaries also present significant challenges. In this paper, we propose a fast, high throughput cell segmentation algorithm by combining top-down shape models and bottom-up image appearance information. A scalable sparse manifold learning method is proposed to model multiple subpopulations of different cell shape priors. Followed by a shape clustering on the manifold, a novel affine transform-approximated active contour model is derived to deform contours without solving a large amount of computationally-expensive Euler-Lagrange equations, and thus dramatically reduces the computational time. To the best of our knowledge, this is the first report of a high throughput cell segmentation algorithm for whole slide scanned pathology specimens using manifold learning to accelerate active contour models. The proposed approach is tested using 12 NET images, and the comparative experiments with the state of the arts demonstrate its superior performance in terms of both efficiency and effectiveness.
Affine kinematics in planar fibrous connective tissues: an experimental investigation.
Jayyosi, C; Affagard, J-S; Ducourthial, G; Bonod-Bidaud, C; Lynch, B; Bancelin, S; Ruggiero, F; Schanne-Klein, M-C; Allain, J-M; Bruyère-Garnier, K; Coret, M
2017-03-29
The affine transformation hypothesis is usually adopted in order to link the tissue scale with the fibers scale in structural constitutive models of fibrous tissues. Thanks to the recent advances in imaging techniques, such as multiphoton microscopy, the microstructural behavior and kinematics of fibrous tissues can now be monitored at different stretching within the same sample. Therefore, the validity of the affine hypothesis can be investigated. In this paper, the fiber reorientation predicted by the affine assumption is compared to experimental data obtained during mechanical tests on skin and liver capsule coupled with microstructural imaging using multiphoton microscopy. The values of local strains and the collagen fibers orientation measured at increasing loading levels are used to compute a theoretical estimation of the affine reorientation of collagen fibers. The experimentally measured reorientation of collagen fibers during loading could not be successfully reproduced with this simple affine model. It suggests that other phenomena occur in the stretching process of planar fibrous connective tissues, which should be included in structural constitutive modeling approaches.
Protein purification by aminosquarylium cyanine dye-affinity chromatography.
Silva, M S; Graça, V C; Reis, L V; Santos, P F; Almeida, P; Queiroz, J A; Sousa, F
2013-12-01
The most selective purification method for proteins and other biomolecules is affinity chromatography. This method is based on the unique biological-based specificity of the biomolecule-ligand interaction and commonly uses biological ligands. However, these ligands may present some drawbacks, mainly because of their cost and lability. Dye-affinity chromatography overcomes the limitations of biological ligands and is widely used owing to the low cost of synthetic dyes and to their resistance to biological and chemical degradation. In this work, immobilized aminosquarylium cyanine dyes are used in order to exploit affinity interactions with standard proteins such as lysozyme, α-chymotrypsin and trypsin. These studies evaluate the affinity interactions occurring between the immobilized ligand and the different proteins, as a reflection of the sum of several molecular interactions, namely ionic, hydrophobic and van der Waals, spread throughout the structure, in a defined spatial manner. The results show the possibility of using an aminosquarylium cyanine dye bearing a N-hexyl pendant chain, with a ligand density of 1.8 × 10(-2) mmol of dye/g of chromatographic support, to isolate lysozyme, α-chymotrypsin and trypsin from a mixture. The application of a decreasing ammonium sulfate gradient resulted in the recovery of lysozyme in the flowthrough. On the other hand, α-chymotrypsin and trypsin were retained, involving different interactions with the ligand. In conclusion, this study demonstrates the potential applicability of ligands such as aminosquarylium cyanine dyes for the separation and purification of proteins by affinity chromatography.
The proton affinities of saturated and unsaturated heterocyclic molecules
Kabli, Samira; van Beelen, Eric S. E.; Ingemann, Steen; Henriksen, Lars; Hammerum, Steen
2006-03-01
The proton affinities derived from G3-calculations of 23 five-membered ring heteroaromatic molecules agree well with the experimentally determined values available in the literature. The calculated local proton affinities show that the principal site of protonation of the heteroaromatic compounds examined is an atom of the ring, carbon when there is only one heteroatom in the ring, and nitrogen where there are two or more heteroatoms. The experimental proton affinities of non-aromatic cyclic ethers, amines and thioethers are also in excellent agreement with the calculated values, with two exceptions (oxetane, N-methylazetidine). The literature proton affinities of the four simple cyclic ethers, oxetane, tetrahydrofuran, tetrahydropyran and oxepane were confirmed by Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometry, in order to examine the disagreement between the values predicted by extrapolation or additivity for tetrahydrofuran and tetrahydropyran and those determined by experiment and by calculation. The proton affinity differences between the pairs tetrahydropyran/1,4-dioxane, piperidine/morpholine and related compounds show that introduction of an additional oxygen atom in the ring considerably lowers the basicity.
Institute of Scientific and Technical Information of China (English)
方进; 邓珂琳; 温家良
2012-01-01
分析了多端直流输电系统的基本原理，利用PSCAD／EMTDC软件建立了多端直流输电系统仿真模型，并建立了含直流断路器的多环网式多端直流输电系统模型，通过仿真研究了直流断路器开断直流输电线路的过程，分析直流断路器在环网式多端直流输电系统中的作用。对直流断路器切除环网式三端直流输电系统一条输电线路的过程及切除故障换流站分别进行了仿真分析。仿真结果表明，当利用直流断路器切除环网式多端直流输电系统的一条输电线路时，输电线路的电流重新分配，能保证功率输送的连续性。在这种情况下，对各个换流站输出或输入的功率影响不大，对与直流系统连接的交流输电网影响很小。当切除故障换流站后，该系统最大限度地保持功率传输及电流的有效分配，保持稳定运行。%Basic principles of multi-terminal direct current （MTDC） power transmission system are analyzed, and utilizing PSCAD/EMTDC software a model of MTDC power transmission system and a model of multi ring-shaped MTDC power transmission system containing DC circuit breakers are built. The process of switching off a DC transmission line by DC circuit breakers is simulated and researched, and the action of DC circuit breakers in multi ring-shaped MTDC transmission system is analyzed. The process of switching off one of transmission lines as well as the process of switching off a faulty converter station in three-terminal DC transmission system by DC circuit breakers are simulated respectively. Simulation results show that when one of DC transmission line in ring-shaped MTDC transmission system is switched off by DC circuit breakers, the currents in DC transmission lines are redistributed to ensure the continuity of power transmission. Under such a condition, the affection on input or output power of each converter station is not notable, and the affection on AC
Institute of Scientific and Technical Information of China (English)
LOU Qi-hong; ZHOU Jun
2007-01-01
In this review article, the development of the double cladding optical fiber for high power fiber lasers is reviewed. The main technology for high power fiber lasers, including laser diode beam shaping, fiber laser pumping techniques, and amplification systems, are discussed in de-tail. 1050 W CW output and 133 W pulsed output are ob-tained in Shanghai Institute of Optics and Fine Mechanics, China. Finally, the applications of fiber lasers in industry are also reviewed.
Ando, A; Hisada, K; Ando, I
1977-10-01
Affinity of many inorganic compounds for the malignant tumor was examined, using the rats which were subcutaneously transplanted with Yoshida sarcoma. And the relations between the uptake rate into the malignant tumor and in vitro binding power to the protein were investigated in these compounds. In these experiments, the bipositive ions and anions had not affinity for the tumor tissue with a few exceptions. On the other hand, Hg, Au and Bi, which have strong binding power to the protein, showed high uptake rate into the malignant tumor. As Hg++, Au+ and Bi+++ are soft acids according to classification of Lewis acids, it was thought that these elements would bind strongly to soft base (R-SH, R-S-) present in the tumor tissue. In many hard acids (according to classification of Lewis acids), the uptake rate into the tumor was shown as a function of ionic potentials (valency/ionic radii) of the metal ions. It is presumed that the chemical bond of these hard acids in the tumor tissue is ionic bond to hard base (R-COO-, R-PO3(2-), R-SO3-, R-NH2).
2002-01-01
A Japanese team has found a way to bend and shape silicon substrates by growing a thin layer of diamond on top. The technique has been proposed as an alternative to mechanical bending, which is currently used to make reflective lenses for X-ray systems and particle physics systems (2 paragraphs).
2016-01-01
This project concerns the implementation of a decentralized algorithm for shape formation. The first idea was to test this algorithm with a swarm of autonomous drones but, due to the lack of time and the complexity of the project, the work was just developed in 2D and in simulation.
OECD Publishing (NJ3), 2010
2010-01-01
"Trends Shaping Education 2010" brings together evidence showing the effects on education of globalisation, social challenges, changes in the workplace, the transformation of childhood, and ICT. To make the content accessible, each trend is presented on a double page, containing an introduction, two charts with brief descriptive text and a set of…
DEFF Research Database (Denmark)
Stenholt, Rasmus; Madsen, Claus B.
2011-01-01
Enabling users to shape 3-D boxes in immersive virtual environments is a non-trivial problem. In this paper, a new family of techniques for creating rectangular boxes of arbitrary position, orientation, and size is presented and evaluated. These new techniques are based solely on position data...
DEFF Research Database (Denmark)
Simovska, Venka; Jensen, Bjarne Bruun
"Shape Up: a School Community Approach to Influencing the Determinants of Childhood Overweight and Obesity, Lessons Learnt" is a report that aims to provide a synthesis of the project overall evaluation documentation, with a view to systematically review and discuss lessons learnt, and to suggest...
Aerodynamically shaped vortex generators
DEFF Research Database (Denmark)
Hansen, Martin Otto Laver; Velte, Clara Marika; Øye, Stig;
2016-01-01
An aerodynamically shaped vortex generator has been proposed, manufactured and tested in a wind tunnel. The effect on the overall performance when applied on a thick airfoil is an increased lift to drag ratio compared with standard vortex generators. Copyright © 2015 John Wiley & Sons, Ltd....
Naz, Farha; Asad, Mohd; Malhotra, Pawan; Islam, Asimul; Ahmad, Faizan; Hassan, Md Imtaiyaz
2014-03-01
Microtubule-associated protein/microtubule affinity-regulating kinase 4 (MARK4) is a member of the family Ser/Thr kinase and involved in numerous biological functions including microtubule bundle formation, nervous system development, positive regulation of programmed cell death, cell cycle control, cell polarity determination, cell shape alterations, cell division etc. For various biophysical and structural studies, we need this protein in adequate quantity. In this paper, we report a novel cloning strategy for MARK4. We have cloned MARK4 catalytic domain including 59 N-terminal extra residues with unknown function and catalytic domain alone in PQE30 vector. The recombinant MARK4 was expressed in the inclusion bodies in M15 cells. The inclusion bodies were solubilized effectively with 1.5% N-lauroylsarcosine in alkaline buffer and subsequently purified using Ni-NTA affinity chromatography in a single step with high purity and good concentration. Purity of protein was checked on sodium dodecyl sulphate-polyacrylamide gel electrophoresis and identified by using mass spectrometry immunoblotting. Refolding of the recombinant protein was validated by ATPase assay. Our purification procedure is quick, simple and produces adequate quantity of proteins with high purity in a limited step.
Anderson, Shannon M; Khalil, Ashraf; Uduman, Mohamed; Hershberg, Uri; Louzoun, Yoram; Haberman, Ann M; Kleinstein, Steven H; Shlomchik, Mark J
2009-12-01
B lymphocytes producing high-affinity Abs are critical for protection from extracellular pathogens, such as bacteria and parasites. The process by which high-affinity B cells are selected during the immune response has never been elucidated. Although it has been shown that high-affinity cells directly outcompete low-affinity cells in the germinal center (GC), whether there are also intrinsic differences between these cells has not been addressed. It could be that higher affinity cells proliferate more rapidly or are more likely to enter cell cycle, thereby outgrowing lower affinity cells. Alternatively, higher affinity cells could be relatively more resistant to cell death in the GC. By comparing high- and low-affinity B cells for the same Ag, we show here that low-affinity cells have an intrinsically higher death rate than do cells of higher affinity, even in the absence of competition. This suggests that selection in the GC reaction is due at least in part to the control of survival of higher affinity B cells and not by a proliferative advantage conferred upon these cells compared with lower affinity B cells. Control over survival rather than proliferation of low- and high-affinity B cells in the GC allows greater diversity not only in the primary response but also in the memory response.
Tidal interaction in compact binaries: a post-Newtonian affine framework
Ferrari, V; Maselli, A
2011-01-01
We develop a semi-analytical approach, based on the post-Newtonian expansion and on the affine approximation, to model the tidal deformation of neutron stars in the coalescence of black hole-neutron star or neutron star-neutron star binaries. Our equations describe, in a unified framework, both the system orbital evolution, and the neutron star deformations. These are driven by the tidal tensor, which we expand at 1/c^3 post-Newtonian order, including spin terms. We test the theoretical framework by simulating black hole-neutron star coalescence up to the onset of mass shedding, which we determine by comparing the shape of the star with the Roche lobe. We validate our approach by comparing our results with those of fully relativistic, numerical simulations.
Enhancing Community Detection By Affinity-based Edge Weighting Scheme
Energy Technology Data Exchange (ETDEWEB)
Yoo, Andy [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sanders, Geoffrey [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Henson, Van [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vassilevski, Panayot [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2015-10-05
Community detection refers to an important graph analytics problem of finding a set of densely-connected subgraphs in a graph and has gained a great deal of interest recently. The performance of current community detection algorithms is limited by an inherent constraint of unweighted graphs that offer very little information on their internal community structures. In this paper, we propose a new scheme to address this issue that weights the edges in a given graph based on recently proposed vertex affinity. The vertex affinity quantifies the proximity between two vertices in terms of their clustering strength, and therefore, it is ideal for graph analytics applications such as community detection. We also demonstrate that the affinity-based edge weighting scheme can improve the performance of community detection algorithms significantly.
k-Schur functions and affine Schubert calculus
Lam, Thomas; Morse, Jennifer; Schilling, Anne; Shimozono, Mark; Zabrocki, Mike
2014-01-01
This book gives an introduction to the very active field of combinatorics of affine Schubert calculus, explains the current state of the art, and states the current open problems. Affine Schubert calculus lies at the crossroads of combinatorics, geometry, and representation theory. Its modern development is motivated by two seemingly unrelated directions. One is the introduction of k-Schur functions in the study of Macdonald polynomial positivity, a mostly combinatorial branch of symmetric function theory. The other direction is the study of the Schubert bases of the (co)homology of the affine Grassmannian, an algebro-topological formulation of a problem in enumerative geometry. This is the first introductory text on this subject. It contains many examples in Sage, a free open source general purpose mathematical software system, to entice the reader to investigate the open problems. This book is written for advanced undergraduate and graduate students, as well as researchers, who want to become familiar with ...
REPRESENTATIONS OF AFFINE HECKE ALGEBRAS OF TYPE G2
Institute of Scientific and Technical Information of China (English)
Xi Nanhua
2009-01-01
Let k be a field and q a nonzero element in k such that the square roots of q are in k.We use Hq to denote an affine Hecke algebra over k of type G2 with parameter q.The purpose of this paper is to study representations of Hq by using based rings of two-sided cells of an affine Weyl group W of type G2.We shall give the classification of irreducible representations of Hq.We also remark that a calculation in [11] actually shows that Theorem 2 in [1] needs a modification, a fact is known to Grojnowski and Tanisaki long time ago.In this paper we also show an interesting relation between Hq and an Hecke algebra corresponding to a certain Coxeter group.Apparently the idea in this paper works for all affine Weyl groups, but that is the theme of another paper.
Fast Affinity Propagation Clustering based on Machine Learning
Directory of Open Access Journals (Sweden)
Shailendra Kumar Shrivastava
2013-01-01
Full Text Available Affinity propagation (AP was recently introduced as an un-supervised learning algorithm for exemplar based clustering. In this paper a novel Fast Affinity Propagation clustering Approach based on Machine Learning (FAPML has been proposed. FAPML tries to put data points into clusters based on the history of the data points belonging to clusters in early stages. In FAPML we introduce affinity learning constant and dispersion constant which supervise the clustering process. FAPML also enforces the exemplar consistency and one of 'N constraints. Experiments conducted on many data sets such as Olivetti faces, Mushroom, Documents summarization, Thyroid, Yeast, Wine quality Red, Balance etc. show that FAPML is up to 54 % faster than the original AP with better Net Similarity.
Single-cell measurement of red blood cell oxygen affinity
Caprio, Di; Higgins, John M; Schonbrun, Ethan
2015-01-01
Oxygen is transported throughout the body by hemoglobin in red blood cells. While the oxygen affinity of blood is well understood and is routinely assessed in patients by pulse oximetry, variability at the single-cell level has not been previously measured. In contrast, single-cell measurements of red blood cell volume and hemoglobin concentration are taken millions of times per day by clinical hematology analyzers and are important factors in determining the health of the hematologic system. To better understand the variability and determinants of oxygen affinity on a cellular level, we have developed a system that quantifies the oxygen saturation, cell volume and hemoglobin concentration for individual red blood cells in high-throughput. We find that the variability in single-cell saturation peaks at an oxygen partial pressure of 2.5%, which corresponds to the maximum slope of the oxygen-hemoglobin dissociation curve. In addition, single-cell oxygen affinity is positively correlated with hemoglobin concentr...
Properties of the Affine Invariant Ensemble Sampler in high dimensions
Huijser, David; Brewer, Brendon J
2015-01-01
We present theoretical and practical properties of the affine-invariant ensemble sampler Markov chain Monte Carlo method. In high dimensions the affine-invariant ensemble sampler shows unusual and undesirable properties. We demonstrate this with an $n$-dimensional correlated Gaussian toy problem with a known mean and covariance structure, and analyse the burn-in period. The burn-in period seems to be short, however upon closer inspection we discover the mean and the variance of the target distribution do not match the expected, known values. This problem becomes greater as $n$ increases. We therefore conclude that the affine-invariant ensemble sampler should be used with caution in high dimensional problems. We also present some theoretical results explaining this behaviour.
Super-Affine Hierarchies and their Poisson Embeddings
Toppan, F
1998-01-01
The link between (super)-affine Lie algebras as Poisson brackets structures and integrable hierarchies provides both a classification and a tool for obtaining superintegrable hierarchies. The lack of a fully systematic procedure for constructing matrix-type Lax operators, which makes the supersymmetric case essentially different from the bosonic counterpart, is overcome via the notion of Poisson embeddings (P.E.), i.e. Poisson mappings relating affine structures to conformal structures (in their simplest version P.E. coincide with the Sugawara construction). A full class of hierarchies can be recovered by using uniquely Lie-algebraic notions. The group-algebraic properties implicit in the super-affine picture allow a systematic derivation of reduced hierarchies by imposing either coset conditions or hamiltonian constraints (or possibly both).
A fast quantum algorithm for the affine Boolean function identification
Younes, Ahmed
2015-02-01
Bernstein-Vazirani algorithm (the one-query algorithm) can identify a completely specified linear Boolean function using a single query to the oracle with certainty. The first aim of the paper is to show that if the provided Boolean function is affine, then one more query to the oracle (the two-query algorithm) is required to identify the affinity of the function with certainty. The second aim of the paper is to show that if the provided Boolean function is incompletely defined, then the one-query and the two-query algorithms can be used as bounded-error quantum polynomial algorithms to identify certain classes of incompletely defined linear and affine Boolean functions respectively with probability of success at least 2/3.
Shape memory alloy thaw sensors
Shahinpoor, Mohsen; Martinez, David R.
1998-01-01
A sensor permanently indicates that it has been exposed to temperatures exceeding a critical temperature for a predetermined time period. An element of the sensor made from shape memory alloy changes shape when exposed, even temporarily, to temperatures above the Austenitic temperature of the shape memory alloy. The shape change of the SMA element causes the sensor to change between two readily distinguishable states.
Duality based contact shape optimization
DEFF Research Database (Denmark)
Vondrák, Vít; Dostal, Zdenek; Rasmussen, John
2001-01-01
An implementation of semi-analytic method for the sensitivity analysis in contact shape optimization without friction is described. This method is then applied to the contact shape optimization.......An implementation of semi-analytic method for the sensitivity analysis in contact shape optimization without friction is described. This method is then applied to the contact shape optimization....
Directory of Open Access Journals (Sweden)
Aldana Trabucchi
Full Text Available Type 1 diabetes mellitus (DM is characterized by autoimmune aggression against pancreatic beta cells resulting in absolute deficiency of insulin secretion. The first detectable sign of emerging autoimmunity during the preclinical asymptomatic period is the appearance of diabetes-related autoantibodies. In children at risk for type 1 DM, high-affinity Insulin autoantibodies reactive to proinsulin, are associated with diabetes risk. Autoantibodies are usually measured by radioligand binding assay (RBA that provides quasi-quantitative values reflecting potency (product between concentration and affinity of specific autoantibodies. Aiming to improve the characterization of the specific humoral immune response, we selected surface plasmon resonance (SPR as an alternative method to measure proinsulin autoantibodies (PAA. This novel technology has allowed real time detection of antibodies interaction and kinetic analysis. Herein, we have employed SPR to characterize the PAA present in sera from 28 childhood-onset (mean age 8.31±4.20 and 23 adult-onset diabetic patients (≥65 years old, BMI<30 in terms of concentration and affinity. When evaluating comparatively samples from both groups, childhood-onset diabetic patients presented lower PAA concentrations and higher affinities (median 67.12×10(-9 M and 3.50×10(7 M(-1, respectively than the adults (median 167.4×10(-9 M and 0.84×10(7 M(-1, respectively. These results are consistent with those from the reference method RBA (Standard Deviation score median 9.49 for childhood-onset group and 5.04 for adult-onset group where the binding can be directly related to the intrinsic affinity of the antibody, suggesting that there is a different etiopathogenic pathway between both types of clinical presentation of the disease. This technology has shown to be a useful tool for the characterization of PAAs parameters as an alternative to radioimmunoassay, with high versatility and reproducibility associated to
Neuroprotective effects of high affinity Σ1 receptor selective compounds.
Luedtke, Robert R; Perez, Evelyn; Yang, Shao-Hua; Liu, Ran; Vangveravong, Suwanna; Tu, Zhude; Mach, Robert H; Simpkins, James W
2012-03-02
We previously reported that the antipsychotic drug haloperidol, a multifunctional D2-like dopamine and sigma receptor subtype antagonist, has neuroprotective properties. In this study we further examined the association between neuroprotection and receptor antagonism by evaluating a panel of novel compounds with varying affinity at sigma and D2-like dopamine receptors. These compounds were evaluated using an in vitro cytotoxicity assay that utilizes a hippocampal-derived cell line, HT-22, in the presence or absence of varying concentrations (5 to 20 mM) of glutamate. While haloperidol was found to be a potent neuroprotective agent in this in vitro cell assay, the prototypic sigma 1 receptor agonist (+)-pentazocine was found not to be neuroprotective. Subsequently, the potency for the neuroprotection of HT-22 cells was evaluated for a) three SV series indoles which have nMolar affinity at D2-like receptors but varying affinity at sigma 1 receptor and b) two benzyl phenylacetamides sigma 1 receptor selective compounds which bind with low affinity at D2-like receptors but have nMolar affinity for the sigma 1 receptor. We observed that cytoprotection correlated with the affinity of the compounds for sigma 1 receptors. Based upon results from the HT-22 cell-based in vitro assay, two phenylacetamides, LS-127 and LS-137, were further evaluated in vivo using a transient middle cerebral artery occlusion (t-MCAO) model of stroke. At a dose of 100 μg/kg, both LS-127 and LS-137 attenuated infarct volume by approximately 50%. These studies provide further evidence that sigma 1 receptor selective compounds can provide neuroprotection in cytotoxic situations. These results also demonstrate that sigma 1 receptor selective benzyl phenylacetamides are candidate pharmacotherapeutic agents that could be used to minimize neuronal death after a stroke or head trauma.
Affine group representation formalism for four dimensional, Lorentzian, quantum gravity
Ching-Yi, Chou; Soo, Chopin
2012-01-01
The Hamiltonian constraint of 4-dimensional General Relativity is recast explicitly in terms of the Chern--Simons functional and the local volume operator. In conjunction with the algebraic quantization program, application of the affine quantization concept due to Klauder facilitates the construction of solutions to all of the the quantum constraints in the Ashtekar variables and their associated Hilbert space. A physical Hilbert space is constructed for Lorentzian signature gravity with nonzero cosmological constant in the form of unitary, irreducible representations of the affine group.
Affine transformation crossed product like algebras and noncommutative surfaces
Arnlind, Joakim
2009-01-01
Several classes of *-algebras associated to the action of an affine transformation are considered, and an investigation of the interplay between the different classes of algebras is initiated. Connections are established that relate representations of *-algebras, geometry of algebraic surfaces, dynamics of affine transformations, graphs and algebras coming from a quantization procedure of Poisson structures. In particular, algebras related to surfaces being inverse images of fourth order polynomials (in R^3) are studied in detail, and a close link between representation theory and geometric properties is established for compact as well as non-compact surfaces.
Affine diffusions and related processes simulation, theory and applications
Alfonsi, Aurélien
2015-01-01
This book gives an overview of affine diffusions, from Ornstein-Uhlenbeck processes to Wishart processes and it considers some related diffusions such as Wright-Fisher processes. It focuses on different simulation schemes for these processes, especially second-order schemes for the weak error. It also presents some models, mostly in the field of finance, where these methods are relevant and provides some numerical experiments. The book explains the mathematical background to understand affine diffusions and analyze the accuracy of the schemes.
Solid support resins and affinity purification mass spectrometry.
Havis, Spencer; Moree, Wilna J; Mali, Sujina; Bark, Steven J
2017-02-28
Co-affinity purification-mass spectrometry (CoAP-MS) is a primary technology for elucidating the protein-protein interactions that form the basis of all biological processes. A critical component of CoAP-MS is the affinity purification (AP) of the bait protein, usually by immobilization of an antibody to a solid-phase resin. This Minireview discusses common resins, reagents, tagging methods, and their consideration for successful AP of tagged proteins. We discuss our experiences with different solid supports, their impact in AP experiments, and propose areas where chemistry can advance this important technology.
The growth rate of symplectic homology and affine varieties
McLean, Mark
2010-01-01
We will show that the cotangent bundle of an integrally hyperbolic manifold is not symplectomorphic to any smooth affine variety. We will also show that the unit cotangent bundle of such a manifold is not Stein fillable by a Stein domain whose completion is symplectomorphic to a smooth affine variety. For instance, these results hold when our manifolds are simply connected with at least one Betti number greater than the corresponding Betti number of the n torus. We use an invariant called the growth rate of symplectic homology to prove this result.
Ferromagnetic Levan Composite: An Affinity Matrix to Purify Lectin
Directory of Open Access Journals (Sweden)
Renata Angeli
2009-01-01
Full Text Available A simple and inexpensive procedure used magnetite and levan to synthesize a composite recovered by a magnetic field. Lectins from Canavalia ensiformis (Con A and Cratylia mollis (Cramoll 1 and Cramoll 1,4 did bind specifically to composite. The magnetic property of derivative favored washing out contaminating proteins and recovery of pure lectins with glucose elution. Cramoll 1 was purified by this affinity binding procedure in two steps instead of a previous three-step protocol with ammonium sulfate fractionation, affinity chromatography on Sephadex G-75, and ion exchange chromatography through a CM-cellulose column.
Automated volumetric breast density derived by shape and appearance modeling
Malkov, Serghei; Kerlikowske, Karla; Shepherd, John
2014-03-01
The image shape and texture (appearance) estimation designed for facial recognition is a novel and promising approach for application in breast imaging. The purpose of this study was to apply a shape and appearance model to automatically estimate percent breast fibroglandular volume (%FGV) using digital mammograms. We built a shape and appearance model using 2000 full-field digital mammograms from the San Francisco Mammography Registry with known %FGV measured by single energy absorptiometry method. An affine transformation was used to remove rotation, translation and scale. Principal Component Analysis (PCA) was applied to extract significant and uncorrelated components of %FGV. To build an appearance model, we transformed the breast images into the mean texture image by piecewise linear image transformation. Using PCA the image pixels grey-scale values were converted into a reduced set of the shape and texture features. The stepwise regression with forward selection and backward elimination was used to estimate the outcome %FGV with shape and appearance features and other system parameters. The shape and appearance scores were found to correlate moderately to breast %FGV, dense tissue volume and actual breast volume, body mass index (BMI) and age. The highest Pearson correlation coefficient was equal 0.77 for the first shape PCA component and actual breast volume. The stepwise regression method with ten-fold cross-validation to predict %FGV from shape and appearance variables and other system outcome parameters generated a model with a correlation of r2 = 0.8. In conclusion, a shape and appearance model demonstrated excellent feasibility to extract variables useful for automatic %FGV estimation. Further exploring and testing of this approach is warranted.
Chang, Tsung-Che; Adak, Avijit K; Lin, Ting-Wei; Li, Pei-Jhen; Chen, Yi-Ju; Lai, Chain-Hui; Liang, Chien-Fu; Chen, Yu-Ju; Lin, Chun-Cheng
2016-03-15
The use of photo-crosslinking glycoprobes represents a powerful strategy for the covalent capture of labile protein complexes and allows detailed characterization of carbohydrate-mediated interactions. The selective release of target proteins from solid support is a key step in functional proteomics. We envisaged that light activation can be exploited for releasing labeled protein in a dual photo-affinity probe-based strategy. To investigate this possibility, we designed a trifunctional, galactose-based, multivalent glycoprobe for affinity labeling of carbohydrate-binding proteins. The resulting covalent protein-probe adduct is attached to a photo-cleavable biotin affinity tag; the biotin moiety enables specific presentation of the conjugate on streptavidin-coated beads, and the photolabile linker allows the release of the labeled proteins. This dual probe promotes both the labeling and the facile cleavage of the target protein complexes from the solid surfaces and the remainder of the cell lysate in a completely unaltered form, thus eliminating many of the common pitfalls associated with traditional affinity-based purification methods.
DEFF Research Database (Denmark)
Buur, Jacob; Mack, Alexandra
Why is it that some business proposals – no matter how well researched with users and business developed – don’t seem to make it through the organizational jungle to become a real product, while others do? How shall we understand the innovative practices that we engage with our ethnographic work...... - in particular in a large corporation? This workshop explores how innovation is socially shaped in organizations. Based on our experiences with practices around innovation and collaboration, we start from three proposition about the social shaping of innovation: • Ideas don't thrive as text (i.e. we need...... to consider other media) • Ideas need socialization (ideas are linked to people, we need to be careful about how we support the social innovation context) • Ideas are local (ideas spring out of a local contingency, we need to take care in how we like them to travel)....
Optimization of structural shapes
Durelli, A. J.
1981-04-01
The direct design of shapes of two dimensional structures, loaded in their plane, within specified design constraints and exhibiting optimum distribution of stresses is studied. Photoelasticity and a large field diffused polariscope is used. The optimization process involves the removal of material (with a hand file or router) from the low stress portions of the hole boundary of the model till an isochromatic fringe coincides with the boundary both on the tensile and compressive segments. Applications are also shown to the design of dove tails and slots in turbine blades and rotors, and to the design of star shaped solid propellant grains for rockets, both for the case of parallel side rays and enlarged tip of rays. The use of other methods, in particular the method using finite elements, to optimize structural forms is discussed.
Imprint of inflation on galaxy shape correlations
Schmidt, Fabian; Chisari, Nora Elisa; Dvorkin, Cora
2015-10-01
We show that intrinsic (not lensing-induced) correlations between galaxy shapes offer a new probe of primordial non-Gaussianity and inflationary physics which is complementary to galaxy number counts. Specifically, intrinsic alignment correlations are sensitive to an anisotropic squeezed limit bispectrum of the primordial perturbations. Such a feature arises in solid inflation, as well as more broadly in the presence of light higher spin fields during inflation (as pointed out recently by Arkani-Hamed and Maldacena). We present a derivation of the all-sky two-point correlations of intrinsic shapes and number counts in the presence of non-Gaussianity with general angular dependence, and show that a quadrupolar (spin-2) anisotropy leads to the analog in galaxy shapes of the well-known scale-dependent bias induced in number counts by isotropic (spin-0) non-Gaussianity. Moreover, in the presence of non-zero anisotropic non-Gaussianity, the quadrupole of galaxy shapes becomes sensitive to far superhorizon modes. These effects come about because long-wavelength modes induce a local anisotropy in the initial power spectrum, with which galaxies will correlate. We forecast that future imaging surveys could provide constraints on the amplitude of anisotropic non-Gaussianity that are comparable to those from the Cosmic Microwave Background (CMB). These are complementary as they probe different physical scales. The constraints, however, depend on the sensitivity of galaxy shapes to the initial conditions which we only roughly estimate from observed tidal alignments.
Audiometric shape and presbycusis.
Demeester, Kelly; van Wieringen, Astrid; Hendrickx, Jan-jaap; Topsakal, Vedat; Fransen, Erik; van Laer, Lut; Van Camp, Guy; Van de Heyning, Paul
2009-04-01
The aim of this study was to describe the prevalence of specific audiogram configurations in a healthy, otologically screened population between 55 and 65 years old. The audiograms of 1147 subjects (549 males and 598 females between 55 and 65 years old) were collected through population registries and classified according to the configuration of hearing loss. Gender and noise/solvent-exposure effects on the prevalence of the different audiogram shapes were determined statistically. In our population 'Flat' audiograms were most dominantly represented (37%) followed by 'High frequency Gently sloping' audiograms (35%) and 'High frequency Steeply sloping' audiograms (27%). 'Low frequency Ascending' audiograms, 'Mid frequency U-shape' audiograms and 'Mid frequency Reverse U-shape' audiograms were very rare (together less than 1%). The 'Flat'-configuration was significantly more common in females, whereas the 'High frequency Steeply sloping'-configuration was more common in males. Exposure to noise and/or solvents did not change this finding. In addition, females with a 'Flat' audiogram had a significantly larger amount of overall hearing loss compared to males. Furthermore, our data reveal a significant association between the prevalence of 'High frequency Steeply sloping' audiograms and the degree of noise/solvent exposure, despite a relatively high proportion of non-exposed subjects showing a 'High frequency Steeply sloping' audiogram as well.
Antiferroelectric Shape Memory Ceramics
Directory of Open Access Journals (Sweden)
Kenji Uchino
2016-05-01
Full Text Available Antiferroelectrics (AFE can exhibit a “shape memory function controllable by electric field”, with huge isotropic volumetric expansion (0.26% associated with the AFE to Ferroelectric (FE phase transformation. Small inverse electric field application can realize the original AFE phase. The response speed is quick (2.5 ms. In the Pb0.99Nb0.02[(Zr0.6Sn0.41-yTiy]0.98O3 (PNZST system, the shape memory function is observed in the intermediate range between high temperature AFE and low temperature FE, or low Ti-concentration AFE and high Ti-concentration FE in the composition. In the AFE multilayer actuators (MLAs, the crack is initiated in the center of a pair of internal electrodes under cyclic electric field, rather than the edge area of the internal electrodes in normal piezoelectric MLAs. The two-sublattice polarization coupling model is proposed to explain: (1 isotropic volume expansion during the AFE-FE transformation; and (2 piezoelectric anisotropy. We introduce latching relays and mechanical clampers as possible unique applications of shape memory ceramics.
Indian Academy of Sciences (India)
Rajesh Kumar; Rama Kant
2009-09-01
We analyse the problem of impedance for a diffusion controlled charge transfer process across an irregular interface. These interfacial irregularities are characterized as two class of random fractals: (i) a statistically isotropic self-affine fractals and (ii) a statistically corrugated self-affine fractals. The information about the realistic fractal surface roughness has been introduced through the bandlimited power-law power spectrum over limited wave numbers. The details of power spectrum of such roughness can be characterized in term of four fractal morphological parameters, viz. fractal dimension (), lower (ℓ), and upper () cut-off length scales of fractality, and the proportionality factor () of power spectrum. Theoretical results are analysed for the impedance of such rough electrode as well as the effect of statistical symmetries of roughness. Impedance response for irregular interface is simplified through expansion over intermediate frequencies. This intermediate frequency expansion with sufficient number of terms offers a good approximation over all frequency regimes. The Nyquist plots of impedance show the strong dependency mainly on three surface morphological parameters i.e. , ℓ and . We can say that our theoretical results also provide an alternative explanation for the exponent in intermediate frequency power-law form.
Input-current shaped ac to dc converters
1986-01-01
The problem of achieving near unity power factor while supplying power to a dc load from a single phase ac source of power is examined. Power processors for this application must perform three functions: input current shaping, energy storage, and output voltage regulation. The methods available for performing each of these three functions are reviewed. Input current shaping methods are either active or passive, with the active methods divided into buck-like and boost-like techniques. In addition to large reactances, energy storage methods include resonant filters, active filters, and active storage schemes. Fast voltage regulation can be achieved by post regulation or by supplementing the current shaping topology with an extra switch. Some indications of which methods are best suited for particular applications concludes the discussion.
McInnis, D. P.; Bolster, D.; Maurice, P. A.
2012-12-01
Transport of reactive sorbing solutes through porous media is commonly quantified by implementing an effective retardation coefficient in the advection-dispersion equation (ADE), which describes dispersion in accordance with Fick's law. However, anomalous (non-Fickian) transport behavior can be observed in systems with heterogeneous retardation coefficients (Dentz & Castro, 2009). In such systems, the ADE is unable to reproduce the non-Fickian nature of plume shapes and breakthrough curves, motivating the development and application of alternative solute transport theories, such as the continuous time random walk (CTRW) or multi-rate mass transfer (MRMT). Heterogeneity in retardation coefficients in practice arises from variability in the geochemical properties controlling sorption-desorption kinetics between the solute and mineral surfaces. These distributions have been described in the context of heterogeneity of the porous medium, but to date little attention has been given to the potential role of a geochemically heterogeneous solute. In this work, we consider a system in which anomalous transport arises during the passage of natural organic matter (NOM), a polydisperse mixture of compounds derived from the breakdown of plants and microorganisms in the environment, through homogeneous laboratory sand columns. NOM solutions were passed through columns containing either hematite, corundum, or a naturally-coated quartz sand at a variety of pH and ionic strength conditions. Influent and effluent NOM concentration was measured as UV absorbance at 254 nm. The resulting breakthrough curves are non-Fickian, displaying power-law tailing at late times. Such curves cannot be predicted by the ADE model. Reactivity of NOM components is known to be related to their molecular weight (MW), which tends to be log-normally distributed in aquatic NOM isolates (Cabaniss et al., 2000). Low-MW compounds are more water-soluble, have a higher diffusion coefficient, and due to their
Linear independence measure of logarithms over affine groups
Huicochea, Mario
2015-01-01
Linear forms in logarithms over connected commutative algebraic groups over the algebraic numbers field have been studied widely. However, the theory of linear forms in logarithms over noncommutative algebraic groups have not been developed as the one of the commutative algebraic groups and in this paper we start studying linear forms in logarithms over affine groups.
Electrochemical affinity biosensors for detection of mycotoxins: A review.
Vidal, Juan C; Bonel, Laura; Ezquerra, Alba; Hernández, Susana; Bertolín, Juan R; Cubel, Carlota; Castillo, Juan R
2013-11-15
This review discusses the current state of electrochemical biosensors in the determination of mycotoxins in foods. Mycotoxins are highly toxic secondary metabolites produced by molds. The acute toxicity of these results in serious human and animal health problems, although it has been only since early 1960s when the first studied aflatoxins were found to be carcinogenic. Mycotoxins affect a broad range of agricultural products, most important cereals and cereal-based foods. A majority of countries, mentioning especially the European Union, have established preventive programs to control contamination and strict laws of the permitted levels in foods. Official methods of analysis of mycotoxins normally requires sophisticated instrumentation, e.g. liquid chromatography with fluorescence or mass detectors, combined with extraction procedures for sample preparation. For about sixteen years, the use of simpler and faster analytical procedures based on affinity biosensors has emerged in scientific literature as a very promising alternative, particularly electrochemical (i.e., amperometric, impedance, potentiometric or conductimetric) affinity biosensors due to their simplicity and sensitivity. Typically, electrochemical biosensors for mycotoxins use specific antibodies or aptamers as affinity ligands, although recombinant antibodies, artificial receptors and molecular imprinted polymers show potential utility. This article deals with recent advances in electrochemical affinity biosensors for mycotoxins and covers complete literature from the first reports about sixteen years ago.
Self-Affine Sets with Positive Lebesgue Measure
Dajani, Karma; Jiang, Kan; Kempton, Tom
2014-01-01
Using techniques introduced by C. G ̈unt ̈urk, we prove that the attractors of a family of overlapping self-affine iterated function systems contain a neighbourhood of zero for all parameters in a certain range. This corresponds to giving conditions under which a single sequence may serve as a ‘simu
Affine group formulation of the Standard Model coupled to gravity
Chou, Ching-Yi; Soo, Chopin
2013-01-01
Using the affine group formalism, we perform a nonperturbative quantization leading to the construction of elements of a physical Hilbert space for full, Lorentzian quantum gravity coupled to the Standard Model in four spacetime dimensions. This paper constitutes a first step toward understanding the phenomenology of quantum gravitational effects stemming from a consistent treatment of minimal couplings to matter.
On global asymptotic controllability of planar affine nonlinear systems
Institute of Scientific and Technical Information of China (English)
SUN Yimin; GUO Lei
2005-01-01
In this paper, we present a necessary and sufficient condition for globally asymptotic controllability of the general planar affine nonlinear systems with single-input.This result is obtained by introducing a new method in the analysis, which is based on the use of some basic results in planar topology and in the geometric theory of ordinary differential equations.
Reconfigurable Control of Input Affine Nonlinear Systems under Actuator Fault
DEFF Research Database (Denmark)
Tabatabaeipour, Mojtaba; Galeazzi, Roberto
2015-01-01
This paper proposes a fault tolerant control method for input-affine nonlinear systems using a nonlinear reconfiguration block (RB). The basic idea of the method is to insert the RB between the plant and the nominal controller such that fault tolerance is achieved without re-designing the nominal...
Demazure modules and vertex models the affine sl(2) case
Foda, O E; Okado, M; Foda, Omar; Misra, Kailash C; Okado, Masato
1996-01-01
We characterize, in the case of affine sl(2), the crystal base of the Demazure module E_w(\\La) in terms of extended Young diagrams or paths for any dominant integral weight \\La and Weyl group element w. Its character is evaluated via two expressions, 'bosonic' and 'fermionic'.
"The Hunger Games": Literature, Literacy, and Online Affinity Spaces
Curwood, Jen Scott
2013-01-01
This article examines adolescent literacy practices related to "The Hunger Games," a young adult novel and the first of a trilogy. By focusing on the interaction of social identities, discourses, and media paratexts within an online affinity space, this ethnographic study offers insight into how young adults engage with contemporary…
T-Duality in Affine NA Toda Models
Gomes, J F; Zimerman, A H
2004-01-01
The construction of Non Abelian affine Toda models is discussed in terms of its underlying Lie algebraic structure. It is shown that a subclass of such non conformal two dimensional integrable models naturally leads to the construction of a pair of actions which share the same spectra and are related by canonical transformations.
Properties of an affine transport equation and its holonomy
Vines, Justin; Nichols, David A.
2016-10-01
An affine transport equation was used recently to study properties of angular momentum and gravitational-wave memory effects in general relativity. In this paper, we investigate local properties of this transport equation in greater detail. Associated with this transport equation is a map between the tangent spaces at two points on a curve. This map consists of a homogeneous (linear) part given by the parallel transport map along the curve plus an inhomogeneous part, which is related to the development of a curve in a manifold into an affine tangent space. For closed curves, the affine transport equation defines a "generalized holonomy" that takes the form of an affine map on the tangent space. We explore the local properties of this generalized holonomy by using covariant bitensor methods to compute the generalized holonomy around geodesic polygon loops. We focus on triangles and "parallelogramoids" with sides formed from geodesic segments. For small loops, we recover the well-known result for the leading-order linear holonomy (˜ Riemann × area), and we derive the leading-order inhomogeneous part of the generalized holonomy (˜ Riemann × area^{3/2}). Our bitensor methods let us naturally compute higher-order corrections to these leading results. These corrections reveal the form of the finite-size effects that enter into the holonomy for larger loops; they could also provide quantitative errors on the leading-order results for finite loops.
An invariant interest point detector under image affine transformation
Institute of Scientific and Technical Information of China (English)
林睿; 黄海波; 孙荣川; 孙立宁
2015-01-01
For vision-based mobile robot navigation, images of the same scene may undergo a general affine transformation in the case of significant viewpoint changes. So, a novel method for detecting affine invariant interest points is proposed to obtain the invariant local features, which is coined polynomial local orientation tensor (PLOT). The new detector is based on image local orientation tensor that is constructed from the polynomial expansion of image signal. Firstly, the properties of local orientation tensor of PLOT are analyzed, and a suitable tuning parameter of local orientation tensor is chosen so as to extract invariant features. The initial interest points are detected by local maxima search for the smaller eigenvalues of the orientation tensor. Then, an iterative procedure is used to allow the initial interest points to converge to affine invariant interest points and regions. The performances of this detector are evaluated on the repeatability criteria and recall versus 1-precision graphs, and then are compared with other existing approaches. Experimental results for PLOT show strong performance under affine transformation in the real-world conditions.
An axially symmetric solution of metric-affine gravity
Vlachynsky, E J; Obukhov, Yu N; Hehl, F W
1996-01-01
We present an exact stationary {\\it axially symmetric} vacuum solution of metric-affine gravity (MAG) which generalises the recently reported spherically symmetric solution. Besides the metric, it carries nonmetricity and torsion as post-Riemannian geometrical structures. The parameters of the solution are interpreted as mass and angular momentum and as dilation, shear and spin charges.
Smooth surfaces from bilinear patches: Discrete affine minimal surfaces
Käferböck, Florian
2013-06-01
Motivated by applications in freeform architecture, we study surfaces which are composed of smoothly joined bilinear patches. These surfaces turn out to be discrete versions of negatively curved affine minimal surfaces and share many properties with their classical smooth counterparts. We present computational design approaches and study special cases which should be interesting for the architectural application. 2013 Elsevier B.V.
General $L\\sb p$ affine isoperimetric inequalities
Haberl, Christoph; Schuster, Franz E.
2009-01-01
Sharp $L\\sb p$ affine isoperimetric inequalities are established for the entire class of $L\\sb p$ projection bodies and the entire class of $L\\sb p$ centroid bodies. These new inequalities strengthen the $L\\sb p$ Petty projection and the $L\\sb p$ Busemann–Petty centroid inequality.
Combinatorial Vector Fields for Piecewise Affine Control Systems
DEFF Research Database (Denmark)
Wisniewski, Rafal; Larsen, Jesper Abildgaard
2008-01-01
This paper is intended to be a continuation of Habets and van Schuppen (2004) and Habets, Collins and van Schuppen (2006), which address the control problem for piecewise-affine systems on an arbitrary polytope or a family of these. Our work deals with the underlying combinatorics of the underlyi...
Prediction of peptide bonding affinity: kernel methods for nonlinear modeling
Bergeron, Charles; Sundling, C Matthew; Krein, Michael; Katt, Bill; Sukumar, Nagamani; Breneman, Curt M; Bennett, Kristin P
2011-01-01
This paper presents regression models obtained from a process of blind prediction of peptide binding affinity from provided descriptors for several distinct datasets as part of the 2006 Comparative Evaluation of Prediction Algorithms (COEPRA) contest. This paper finds that kernel partial least squares, a nonlinear partial least squares (PLS) algorithm, outperforms PLS, and that the incorporation of transferable atom equivalent features improves predictive capability.
HAUSDORFF DIMENSION OF GENERALIZED STATISTICALLY SELF-AFFINE FRACTALS
Institute of Scientific and Technical Information of China (English)
余旌胡; 丁立新
2004-01-01
The authors consider generalized statistically self-affine recursive fractals K with random numbers of subsets on each level. They obtain the Hausdorff dimensions of K without considering whether the subsets on each level are non-overlapping or not. They also give some examples to show that many important sets are the special cases of their models.
An Affine Invariant $k$-Nearest Neighbor Regression Estimate
Biau, Gérard; Dujmovic, Vida; Krzyzak, Adam
2012-01-01
We design a data-dependent metric in $\\mathbb R^d$ and use it to define the $k$-nearest neighbors of a given point. Our metric is invariant under all affine transformations. We show that, with this metric, the standard $k$-nearest neighbor regression estimate is asymptotically consistent under the usual conditions on $k$, and minimal requirements on the input data.
Self-affine roughness influence on the Casimir effect
Palasantzas, G
2005-01-01
In this work we investigate the influence of self-affine roughness on the Casimir energy for plate-plate geometry. The plate roughness is characterized by the rms roughness amplitude w, the lateral correlation length xi, and the roughness exponent H. It is shown that the latter has a prominent effec
Evaluation Codes from an Affine Veriety Code Perspective
DEFF Research Database (Denmark)
Geil, Hans Olav
2008-01-01
Evaluation codes (also called order domain codes) are traditionally introduced as generalized one-point geometric Goppa codes. In the present paper we will give a new point of view on evaluation codes by introducing them instead as particular nice examples of affine variety codes. Our study...
Student Engagement and Neoliberalism: Mapping an Elective Affinity
Zepke, Nick
2015-01-01
The purpose of this article is to argue that student engagement, an important area for research about learning and teaching in formal higher education, has an elective affinity with neoliberalism, a hegemonic ideology in many countries of the developed world. The paper first surveys an extensive research literature examining student engagement and…
A Coarse-to-Fine Method for Shape Recognition
Institute of Scientific and Technical Information of China (English)
Hui-Xuan Tang; Hui Wei
2007-01-01
In this paper the deformation invariant curve matching problem is addressed. The proposed approach exploits an image pyramid to constrain correspondence search at a finer level with those at a coarser level. In comparison to previous methods, this approach conveys much richer information: curve topology, affine geometry and local intensity are combined together to seek correspondences. In experiments, the method is tested in two applications, contour matching and shape recognition, and the results show that the approach is effective under perspective and articulated deformations.
Shape descriptors for mode-shape recognition and model updating
Wang, W.; Mottershead, J. E.; Mares, C.
2009-08-01
The most widely used method for comparing mode shapes from finite elements and experimental measurements is the Modal Assurance Criterion (MAC), which returns a single numerical value and carries no explicit information on shape features. New techniques, based on image processing (IP) and pattern recognition (PR) are described in this paper. The Zernike moment descriptor (ZMD), Fourier descriptor (FD), and wavelet descriptor (WD), presented in this article, are the most popular shape descriptors having properties that include efficiency of expression, robustness to noise, invariance to geometric transformation and rotation, separation of local and global shape features and computational efficiency. The comparison of mode shapes is readily achieved by assembling the shape features of each mode shape into multi-dimensional shape feature vectors (SFVs) and determining the distances separating them.
Landscape of atomic nuclear shapes
Moon, Chang-Bum
2016-01-01
We exhibit a wide variety of the nuclear shape phases over the nuclear chart along with a shell model scheme. Various nuclear shapes are demonstrated within the framework of proton-neutron spin-orbital interactions; ferro-deformed, sub-ferro-deformed, and spherical shapes. The spherical shape is classified into the three magic-number categories in view of a large shell gap mechanism; double-magic nuclei I, double magic nuclei II, and double magic nuclei III. We discuss nuclear shape coexistence in the space Z = 76 to 84 as providing a new way to understanding the dynamical shape phases.
Semiempirical Theories of the Affinities of Negative Atomic Ions
Edie, John W.
1961-01-01
The determination of the electron affinities of negative atomic ions by means of direct experimental investigation is limited. To supplement the meager experimental results, several semiempirical theories have been advanced. One commonly used technique involves extrapolating the electron affinities along the isoelectronic sequences, The most recent of these extrapolations Is studied by extending the method to Include one more member of the isoelectronic sequence, When the results show that this extension does not increase the accuracy of the calculations, several possible explanations for this situation are explored. A different approach to the problem is suggested by the regularities appearing in the electron affinities. Noting that the regular linear pattern that exists for the ionization potentials of the p electrons as a function of Z, repeats itself for different degrees of ionization q, the slopes and intercepts of these curves are extrapolated to the case of the negative Ion. The method is placed on a theoretical basis by calculating the Slater parameters as functions of q and n, the number of equivalent p-electrons. These functions are no more than quadratic in q and n. The electron affinities are calculated by extending the linear relations that exist for the neutral atoms and positive ions to the negative ions. The extrapolated. slopes are apparently correct, but the intercepts must be slightly altered to agree with experiment. For this purpose one or two experimental affinities (depending on the extrapolation method) are used in each of the two short periods. The two extrapolation methods used are: (A) an isoelectronic sequence extrapolation of the linear pattern as such; (B) the same extrapolation of a linearization of this pattern (configuration centers) combined with an extrapolation of the other terms of the ground configurations. The latter method Is preferable, since it requires only experimental point for each period. The results agree within
Power corrections, renormalons and resummation
Energy Technology Data Exchange (ETDEWEB)
Beneke, M.
1996-08-01
I briefly review three topics of recent interest concerning power corrections, renormalons and Sudakov resummation: (a) 1/Q corrections to event shape observables in e(+)e(-) annihilation, (b) power corrections in Drell-Yan production and (c) factorial divergences that arise in resummation of large infrared (Sudakov) logarithms in moment or `real` space.
Kosar-Hashemi, Behjat; Irwin, Jennifer A; Higgins, Jody; Rahman, Sadequr; Morell, Matthew K
2006-05-01
A 2-D affinity electrophoretic technique (2-DAE) has been used to isolate proteins that interact with various starch components from total barley endosperm extracts. In the first dimension, proteins are separated by native PAGE. The second-dimensional gel contains polysaccharides such as amylopectin and glycogen. The migration of starch-interacting proteins in this dimension is determined by their affinity towards a particular polysaccharide and these proteins are therefore spatially separated from the bulk of proteins in the crude extract. Four distinct proteins demonstrate significant affinity for amylopectin and have been identified as starch branching enzyme I (SBEI), starch branching enzyme IIa (SBEIIa), SBEIIb and starch phosphorylase using polyclonal antibodies and zymogram activity analysis. In the case of starch phosphorylase, a protein spot was excised from a 2-DAE polyacrylamide gel and analysed using Q-TOF MS/MS, resulting in the alignment of three internal peptide sequences with the known sequence of the wheat plastidic starch phosphorylase isoform. This assignment was confirmed by the determination of the enzyme's function using zymogram analysis. Dissociation constants (Kd) were calculated for the three enzymes at 4 degrees C and values of 0.20, 0.21 and 1.3 g/L were determined for SBEI, SBEIIa and starch phosphorylase, respectively. Starch synthase I could also be resolved from the other proteins in the presence of glycogen and its identity was confirmed using a polyclonal antibody and by activity analysis. The 2-DAE method described here is simple, though powerful, enabling protein separation from crude extracts on the basis of function.
Hiroichi, Hasegawa
1981-01-01
The shape of meteorites is described by axial ratio (b/a), where a and b are the longest and the intermediate axial lengths of meteorite, respectively. Used samples are the Yamato meteorites recovered in 1973-1975. Distribution of (b/a) and the average value of 0.730 of 930 chondrites except carbonaceous ones are obtained. The results are similar to those of basalt fragments in laboratory impact experiment. Five chondrite showers are also analyzed. Their mass spectra are well represented by ...
Nuclear power plant maintainability.
Seminara, J L; Parsons, S O
1982-09-01
In the mid-1970s a general awareness of human factors engineering deficiencies associated with power plant control rooms took shape and the Electric Power Research Institute (EPRI) awarded the Lockheed Corporation a contract to review the human factors aspects of five representative operational control rooms and their associated simulators. This investigation revealed a host of major and minor deficiencies that assumed unforeseen dimensions in the post- Three Mile Island accident period. In the course of examining operational problems (Seminara et al, 1976) and subsequently the methods for overcoming such problems (Seminara et al, 1979, 1980) indications surfaced that power plants were far from ideal in meeting the needs of maintenance personnel. Accordingly, EPRI sponsored an investigation of the human factors aspects of power plant maintainability (Seminara, 1981). This paper provides an overview of the maintainability problems and issues encountered in the course of reviewing five nuclear power plants.
基于Zernike矩的模糊与仿射混合不变量研究%Study on Blur and Affine Combined Invariants Based on Zernike Moment
Institute of Scientific and Technical Information of China (English)
蔡小帅; 张荣国; 李富萍; 刘小君
2014-01-01
Zernike moment,as a shape descriptor,has been widely used in image characteristics extraction and pattern recognition. It is low information redundancy and not sensitive to noise. To improve the shape description capability of the images which are degraded by combined blur and affine transformation,a new shape descriptor based on Zernike moment is proposed. The normalization method is used to construct affine invariants of Zernike moment. The combined blur and affine moment invariants of Zernike moment is achieved by the help of the blur invariants. The combined moment invariants is used as the shape descriptor to describe the shape feature of images,and is implemented comparison with the combined affine and blur invariants based on geometric moment with relative error. Experimental results show that the combined blur and affine invariants of Zernike moment can get better shape description and invariance in combined degrades,and robustness to noise.%Zernike矩作为形状描述子,其信息冗余度低且对噪声不敏感,在图像特征提取和模式识别中得到了广泛应用。为提高Zernike矩对含有模糊和仿射图像的形状描述能力,提出一种基于Zernike矩的形状描述子,该描述子使用规范化方法构造Zernike矩的仿射不变量,结合Zernike矩的模糊不变量得到Zernike矩的模糊和仿射混合不变量。将该矩混合不变量作为形状描述子描述图像的形状特征,并与几何矩模糊和仿射混合不变量进行对比实验,结果表明,Zernike矩的模糊和仿射混合不变量在混合形变下形状描述能力较强,具有不变性,并且对噪声的鲁棒性较好。
Modelling Distributed Shape Priors by Gibbs Random Fields of Second Order
Flach, Boris
2011-01-01
We analyse the potential of Gibbs Random Fields for shape prior modelling. We show that the expressive power of second order GRFs is already sufficient to express simple shapes and spatial relations between them simultaneously. This allows to model and recognise complex shapes as spatial compositions of simpler parts.
Automated transformation-invariant shape recognition through wavelet multiresolution
Brault, Patrice; Mounier, Hugues
2001-12-01
We present here new results in Wavelet Multi-Resolution Analysis (W-MRA) applied to shape recognition in automatic vehicle driving applications. Different types of shapes have to be recognized in this framework. They pertain to most of the objects entering the sensors field of a car. These objects can be road signs, lane separation lines, moving or static obstacles, other automotive vehicles, or visual beacons. The recognition process must be invariant to global, affine or not, transformations which are : rotation, translation and scaling. It also has to be invariant to more local, elastic, deformations like the perspective (in particular with wide angle camera lenses), and also like deformations due to environmental conditions (weather : rain, mist, light reverberation) or optical and electrical signal noises. To demonstrate our method, an initial shape, with a known contour, is compared to the same contour altered by rotation, translation, scaling and perspective. The curvature computed for each contour point is used as a main criterion in the shape matching process. The original part of this work is to use wavelet descriptors, generated with a fast orthonormal W-MRA, rather than Fourier descriptors, in order to provide a multi-resolution description of the contour to be analyzed. In such way, the intrinsic spatial localization property of wavelet descriptors can be used and the recognition process can be speeded up. The most important part of this work is to demonstrate the potential performance of Wavelet-MRA in this application of shape recognition.
Pairwise harmonics for shape analysis
Zheng, Youyi
2013-07-01
This paper introduces a simple yet effective shape analysis mechanism for geometry processing. Unlike traditional shape analysis techniques which compute descriptors per surface point up to certain neighborhoods, we introduce a shape analysis framework in which the descriptors are based on pairs of surface points. Such a pairwise analysis approach leads to a new class of shape descriptors that are more global, discriminative, and can effectively capture the variations in the underlying geometry. Specifically, we introduce new shape descriptors based on the isocurves of harmonic functions whose global maximum and minimum occur at the point pair. We show that these shape descriptors can infer shape structures and consistently lead to simpler and more efficient algorithms than the state-of-the-art methods for three applications: intrinsic reflectional symmetry axis computation, matching shape extremities, and simultaneous surface segmentation and skeletonization. © 2012 IEEE.
Horst, Carol
2012-01-01
A powerful thing happens when one object is placed next to another: A relationship is suggested and a visual dialogue of sorts is created. Sculptors and architects are especially sensitive to the fact that harmonious relationships between elements can sometimes be more interesting than the elements themselves. Two-dimensional visual interaction…
Walkup, Ward G; Kennedy, Mary B
2014-06-01
PDZ (PSD-95, DiscsLarge, ZO1) domains function in nature as protein binding domains within scaffold and membrane-associated proteins. They comprise ∼90 residues and make specific, high affinity interactions with complementary C-terminal peptide sequences, with other PDZ domains, and with phospholipids. We hypothesized that the specific, strong interactions of PDZ domains with their ligands would make them well suited for use in affinity chromatography. Here we describe a novel affinity chromatography method applicable for the purification of proteins that contain PDZ domain-binding ligands, either naturally or introduced by genetic engineering. We created a series of affinity resins comprised of PDZ domains from the scaffold protein PSD-95, or from neuronal nitric oxide synthase (nNOS), coupled to solid supports. We used them to purify heterologously expressed neuronal proteins or protein domains containing endogenous PDZ domain ligands, eluting the proteins with free PDZ domain peptide ligands. We show that Proteins of Interest (POIs) lacking endogenous PDZ domain ligands can be engineered as fusion products containing C-terminal PDZ domain ligand peptides or internal, N- or C-terminal PDZ domains and then can be purified by the same method. Using this method, we recovered recombinant GFP fused to a PDZ domain ligand in active form as verified by fluorescence yield. Similarly, chloramphenicol acetyltransferase (CAT) and β-Galactosidase (LacZ) fused to a C-terminal PDZ domain ligand or an N-terminal PDZ domain were purified in active form as assessed by enzymatic assay. In general, PDZ domains and ligands derived from PSD-95 were superior to those from nNOS for this method. PDZ Domain Affinity Chromatography promises to be a versatile and effective method for purification of a wide variety of natural and recombinant proteins.
Heczko, Oleg; Straka, Ladislav; Soderberg, Outi; Hannula, Simo-Pekka
2005-05-01
Single crystal specimens of having compositions close to Ni2MnGa and exhibiting magnetic shape memory effect (MSME) were tested in a rotating magnetic field at a frequency of 5.7 Hz. The applied magnetic field, about 0.7 T was strong enough to induce the MSME. Test of one specimen was discontinued because of the structural failure of the specimens after 0.5 million cycles. Second specimen was tested up to 37 millions cycles. The evolution of the martensitic morphology and crack propagation were observed by optical microscopy. To characterize the magnetic shape memory behavior the simultaneous measurements of the field-induced strain and magnetization as a function of the magnetic field and external load was used. The full MSM effect, about 6% obtained prior the test, decreased to about 3% during the first million cycles. This value stayed then approximately constant up to 37 millions cycles of rotating magnetic field. The magnetic field needed to initiate the MSME increased. The observed behavior is discussed within the framework of observed martensitic band structure in the specimens and the existence of initial cracks and other obstacles for martensitic twin boundary motion.
Issues in Biological Shape Modelling
DEFF Research Database (Denmark)
Hilger, Klaus Baggesen
This talk reflects parts of the current research at informatics and Mathematical Modelling at the Technical University of Denmark within biological shape modelling. We illustrate a series of generalizations, modifications, and applications of the elements of constructing models of shape or appear......This talk reflects parts of the current research at informatics and Mathematical Modelling at the Technical University of Denmark within biological shape modelling. We illustrate a series of generalizations, modifications, and applications of the elements of constructing models of shape...
AN AFFINE-INVARIANT SAMPLER FOR EXOPLANET FITTING AND DISCOVERY IN RADIAL VELOCITY DATA
Energy Technology Data Exchange (ETDEWEB)
Hou Fengji; Hogg, David W. [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Goodman, Jonathan; Weare, Jonathan [Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, NY 10012 (United States); Schwab, Christian, E-mail: fh417@nyu.edu [Department of Astronomy, Yale University, 260 Whitney Avenue, New Haven, CT 06511 (United States)
2012-02-01
Markov chain Monte Carlo (MCMC) proves to be powerful for Bayesian inference and in particular for exoplanet radial velocity fitting because MCMC provides more statistical information and makes better use of data than common approaches like chi-square fitting. However, the nonlinear density functions encountered in these problems can make MCMC time-consuming. In this paper, we apply an ensemble sampler respecting affine invariance to orbital parameter extraction from radial velocity data. This new sampler has only one free parameter, and does not require much tuning for good performance, which is important for automatization. The autocorrelation time of this sampler is approximately the same for all parameters and far smaller than Metropolis-Hastings, which means it requires many fewer function calls to produce the same number of independent samples. The affine-invariant sampler speeds up MCMC by hundreds of times compared with Metropolis-Hastings in the same computing situation. This novel sampler would be ideal for projects involving large data sets such as statistical investigations of planet distribution. The biggest obstacle to ensemble samplers is the existence of multiple local optima; we present a clustering technique to deal with local optima by clustering based on the likelihood of the walkers in the ensemble. We demonstrate the effectiveness of the sampler on real radial velocity data.
Density Gradient Ultracentrifugation to Isolate Endogenous Protein Complexes after Affinity Capture.
Fernandez-Martinez, Javier; LaCava, John; Rout, Michael P
2016-07-01
This protocol describes the isolation of native protein complexes by density gradient ultracentrifugation. The outcome of an affinity capture and native elution experiment is generally a mixture of (1) the complex(es) associated with the protein of interest under the specific conditions of capture, (2) fragments of the complex generated by degradation or disassembly during the purification procedure, and (3) the protease or reagent used to natively elute the sample. To separate these components and isolate a homogeneous complex, an additional step of purification is required. Rate-zonal density gradient ultracentrifugation is a reliable and powerful technique for separating particles based on their hydrodynamic volume. The density gradient is generated by mixing low- and high-density solutions of a suitable low-molecular-weight inert solute (e.g., sucrose or glycerol). The gradient is formed in a solvent that could be any of the solvents used for the affinity capture and native elution and should help to preserve the structure and activity of the assembly.
An Affine-invariant Sampler for Exoplanet Fitting and Discovery in Radial Velocity Data
Hou, Fengji; Goodman, Jonathan; Hogg, David W.; Weare, Jonathan; Schwab, Christian
2012-02-01
Markov chain Monte Carlo (MCMC) proves to be powerful for Bayesian inference and in particular for exoplanet radial velocity fitting because MCMC provides more statistical information and makes better use of data than common approaches like chi-square fitting. However, the nonlinear density functions encountered in these problems can make MCMC time-consuming. In this paper, we apply an ensemble sampler respecting affine invariance to orbital parameter extraction from radial velocity data. This new sampler has only one free parameter, and does not require much tuning for good performance, which is important for automatization. The autocorrelation time of this sampler is approximately the same for all parameters and far smaller than Metropolis-Hastings, which means it requires many fewer function calls to produce the same number of independent samples. The affine-invariant sampler speeds up MCMC by hundreds of times compared with Metropolis-Hastings in the same computing situation. This novel sampler would be ideal for projects involving large data sets such as statistical investigations of planet distribution. The biggest obstacle to ensemble samplers is the existence of multiple local optima; we present a clustering technique to deal with local optima by clustering based on the likelihood of the walkers in the ensemble. We demonstrate the effectiveness of the sampler on real radial velocity data.
Directory of Open Access Journals (Sweden)
Hao Chang
2016-01-01
Full Text Available We are concerned with an optimal investment-consumption problem with stochastic affine interest rate and stochastic volatility, in which interest rate dynamics are described by the affine interest rate model including the Cox-Ingersoll-Ross model and the Vasicek model as special cases, while stock price is driven by Heston’s stochastic volatility (SV model. Assume that the financial market consists of a risk-free asset, a zero-coupon bond (or a convertible bond, and a risky asset. By using stochastic dynamic programming principle and the technique of separation of variables, we get the HJB equation of the corresponding value function and the explicit expressions of the optimal investment-consumption strategies under power utility and logarithmic utility. Finally, we analyze the impact of market parameters on the optimal investment-consumption strategies by giving a numerical example.
Zehender, Hartmut; Mayr, Lorenz M
2007-02-01
High-throughput screening of chemical libraries for compounds that interfere with a particular molecular target is among the most powerful methodologies applied in lead discovery at present. In this review, the authors describe a label-free, homogeneous, affinity-selection-based technology developed at Novartis, termed SpeedScreen, which is compared with similar technologies used for high-throughput screening in the pharmaceutical and biotechnology industries. The focus at present of SpeedScreen is twofold: first, this technology is applied to orphan genomic targets and to those targets that are non-tractable by a functional assay; second, this technology is applied complementary to the well-established traditional methodologies for the screening of molecular targets. In summary, the authors discuss the value of affinity-selection-based high-throughput screening as a complementary technology to the common functional screening platforms and the benefits as well as the limitations of this new technology are outlined.
Institute of Scientific and Technical Information of China (English)
ZHANG Dong-Hai; LI Hui-Ling
2009-01-01
Self-affine multiplicity scaling is investigated in the framework of a two-dimensional factorial mo-ment methodology using the concept of the Hurst exponent (H). Investigation of the experimental data of medium-energy knocked-out target protons in SaKr-AgBr interactions at 1.7 AGeV reveals that the best power law behavior is exhibited for H = 0.4, indicating a self-affine multiplicity fluctuation pattern. Multifractalit yamong the knocked-out target protons is also observed in the data.
The Low-Degree Shape of Mercury
Perry, M. E.; Neumann, G. A.; Mazarico, E.; Hauck, S. A., II; Solomon, S. C.; Zuber, M. T.; Smith, D. E.; Phillips, R. J.; Margot, J. L.; Johnson, C. L.; Ernst, C. M.; Oberst, J.
2015-12-01
The shape of Mercury, particularly when combined with its geoid, provides clues to the planet's internal structure, thermal evolution, and rotational history. Twenty-five million elevation measurements of the northern hemisphere, acquired by the Mercury Laser Altimeter on the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft, were combined with 378 occultation measurements of radio-frequency signals from the spacecraft in the planet's southern hemisphere to reveal the low-degree shape of Mercury. We solved for the spherical-harmonic coefficients through degree and order 128 and found that Mercury's mean radius is 2439.36±0.02 km. The offset between the planet's centers of mass and figure is negligible (40±40 m) along the polar axis and modest (140±50 m) in the equatorial plane. Mercury's spherical-harmonic shape spectrum is dominated by degree 2, and the planet's first-order shape is that of a triaxial ellipsoid with semimajor axes a, b, and c. The polar radius, c, is 1.65 km less than (a+b)/2, and the equatorial difference, a-b, is 1.25 km. The long axis is rotated 15° west of Mercury's dynamically defined principal axis. Mercury's geoid is similarly dominated by degree 2 and well described by a triaxial ellipsoid. The degree-2 geoid and shape are highly correlated, but the power spectral density of the geoid at degree 2 is only 1% of its shape counterpart, implying substantial compensation of elevation variations on a global scale and that Mercury is not in hydrostatic equilibrium.
SIFT Feature Matching Algorithm with Local Shape Context
Directory of Open Access Journals (Sweden)
Gu Lichuan
2013-05-01
Full Text Available SIFT (Scale Invariant Feature Transform is one of the most effective local feature of scale, rotation and illumination invariant, which is widely used in the field of image matching. While there will be a lot mismatches when an image has many similar regions. In this study, an improved SIFT feature matching algorithm with local shape context is put forward. The feature vectors are computed by dominant orientation assignment to each feature point based on elliptical neighboring region and with local shape context and then the feature vectors are matched by using Euclidean distance and the X2 distance. The experiment indicates that the improved algorithm can reduce mismatch probability and acquire good performance on affine invariance, improves matching results greatly.
Global Gravity Inversion of Bodies with Arbitrary Shape
Tricarico, Pasquale
2013-01-01
Gravity inversion allows us to constrain the interior mass distribution of a planetary body using the observed shape, rotation, and gravity. Traditionally, techniques developed for gravity inversion can be divided into Monte Carlo methods, matrix inversion methods, and spectral methods. Here we employ both matrix inversion and Monte Carlo in order to explore the space of exact solutions, in a method which is particularly suited for arbitrary shape bodies. We expand the mass density function using orthogonal polynomials, and map the contribution of each term to the global gravitational field generated. This map is linear in the density terms, and can be pseudo-inverted in the under-determined regime using QR decomposition, to obtain a basis of the affine space of exact interior structure solutions. As the interior structure solutions are degenerate, assumptions have to be made in order to control their properties, and these assumptions can be transformed into scalar functions and used to explore the solutions ...
Effects of pH on the Shape of Alginate Particles and Its Release Behavior
Directory of Open Access Journals (Sweden)
Jui-Jung Chuang
2017-01-01
Full Text Available A vast majority of alginate particles exist as spheres in most practical uses, and both the particle shape and size are the key factors dominating the applications and performance of alginate gels. Therefore, it becomes an issue of great interest to investigate the aspheric alginate particles. As the first step, various shaped alginate particles were formed due to various pH values in gelation solutions. It was experimentally demonstrated that a low pH brought about an oblate shape, and particularly lower concentrations of both alginate and divalent cations resulted in a flattened oblate shape. Ba2+ acting as a cross-linker had a less impact on the particle shape than Ca2+ due to a higher affinity in alginate intermolecular cross-linking. With a larger surface area, an oblate particle offered a higher release rate than a spheric one.
IMF shape constraints from stellar populations and dynamics from CALIFA
Lyubenova, M; van de Ven, G; Falcón-Barroso, J; Galbany, L; Gallazzi, A; García-Benito, R; Delgado, R González; Husemann, B; La Barbera, F; Marino, R A; Mast, D; Mendez-Abreu, J; Peletier, R F P; Sánchez-Blázquez, P; Sánchez, S F; Trager, S C; Bosch, R C E van den; Vazdekis, A; Walcher, C J; Zhu, L; Zibetti, S; Ziegler, B; Bland-Hawthorn, J
2016-01-01
In this letter we describe how we use stellar dynamics information to constrain the shape of the stellar IMF in a sample of 27 early-type galaxies from the CALIFA survey. We obtain dynamical and stellar mass-to-light ratios, $\\Upsilon_\\mathrm{dyn}$ and $\\Upsilon_{\\ast}$, over a homogenous aperture of 0.5~$R_{e}$. We use the constraint $\\Upsilon_\\mathrm{dyn} \\ge \\Upsilon_{\\ast}$ to test two IMF shapes within the framework of the extended MILES stellar population models. We rule out a single power law IMF shape for 75% of the galaxies in our sample. Conversely, we find that a double power law IMF shape with a varying high-mass end slope is compatible (within 1$\\sigma$) with 95% of the galaxies. We also show that dynamical and stellar IMF mismatch factors give consistent results for the systematic variation of the IMF in these galaxies.
Conservation laws in metric-affine gravitation theories: Superpotentials
Energy Technology Data Exchange (ETDEWEB)
Giachetta, G.; Giambo`, R.; Mangiarotti, L. [Camerino, Univ. (Italy). Dipt. di Matematica e Fisica
1997-08-01
By applying the machinery of the Lagrangian formalism in field theory, they study the conservation laws of a metric-affine gravitation theory in which the dynamical fields are the spin structures, the linear connections and the fermion fields on a 4-dimensional manifold. The system is assumed to be symmetric with respect to the group of all transformations of the spin bundle. The results obtained are the following. The currents associated with the infinitesimal vertical transformations of the symmetry group vanish identically. As a consequence, to every vector field on the world manifold there corresponds a well-defined current, namely the energy-momentum current. The superpotential term contained in this current is independent of the presence of fermion fields. The expression they get for the superpotential coincides with that found in the purely metric-affine context and generalized the well-known expression obtained by Komar.
Polysulfone affinity membranes for the treatment of amino acid mixtures.
Rodemann, K; Staude, E
1995-06-20
Affinity membranes for the treatment of solutions containing amino acids were obtained via lithiating polysulfone that was subsequently converted with glycidylether. From this polymer asymmetric ultrafiltration membranes were cast. The membranes were reacted with iminodiacetic acid yielding membranes fitted out with bidentate chelates. The same reaction path was applied to commercially available symmetric microfiltration membranes. The chelate-bearing membranes were complexed with Cu, Ni, and Zn ions. For the experiments with amino acids only the Cu-complexed membranes were used. The complexation constants for histidine and tryptophan for six different membranes were determined. Because of the affinity of these two amino acids for the complexed Cu ions, they could easily be separated from solutions containing amino acids such as alanine, glycine, and valine. Also, concentrating very dilute amino acid solutions was carried out successfully.
Restricted Quantum Affine Symmetry of Perturbed Minimal Models
Felder, G
1992-01-01
We study the structure of superselection sectors of an arbitrary perturbation of a conformal field theory. We describe how a restriction of the q-deformed $\\hat{sl(2)}$ affine Lie algebra symmetry of the sine-Gordon theory can be used to derive the S-matrices of the $\\Phi^{(1,3)}$ perturbations of the minimal unitary series. This analysis provides an identification of fields which create the massive kink spectrum. We investigate the ultraviolet limit of the restricted sine-Gordon model, and explain the relation between the restriction and the Fock space cohomology of minimal models. We also comment on the structure of degenerate vacuum states. Deformed Serre relations are proven for arbitrary affine Toda theories, and it is shown in certain cases how relations of the Serre type become fractional spin supersymmetry relations upon restriction.
A NOVEL METAL CHELATE AFFINITY ADSORBENT FOR PROTEIN UPTAKE
Institute of Scientific and Technical Information of China (English)
WANGYongjian; BAIShu; 等
2001-01-01
In this article,a spherical chitosan gel crosslinked by epichlorohydrin was prepared.It was then loaded with copper ions to produce a metal chelate affinity adsorbent for protein.The uptake of bovine serum albumin(BSA)by the affinity adsorbent was investigated.and the adsorption capacity for BSA as high as 40mg/g-wet beads was observed.The adsorption equilibrium data was well correlated by the Langmuir equation.The adsorption was considerably affected by pH.In additio.The amount of BSA adsorbed onto the beads decreased with the increasing of aqueous phase ionic strength,so adsorbed BAS can be desorbed by adjusting pH orionic strength of the solution.
Determination of NO chemical affinities of benzyl nitrite in acetonitrile
Institute of Scientific and Technical Information of China (English)
Xin LI; Xiaoqing ZHU; Jinpei CHENG
2008-01-01
There is an increasing interest in the study of NO chemical affinities of organic nitrites, for the bio-logical and physiological effects of organic nitrites seem to be due to their ability to release NO. In this paper, NO chemical affinities of ten substituted benzyl nitrites were determined by titration calorimetry combined with a ther-modynamic cycle in acetonitrile solution. The results show that ΔHhet(O-NO)s of benzyl nitrites are substan-tially larger than the corresponding ΔHhomo(O-NO)s, suggesting that these O-nitroso compounds much more easily release NO radicals by the O-NO bond homolytic cleavage. It is believed that the structural and energetic information disclosed in this work should be useful in understanding chemical and biological functions of organic nitrites.
Lifting, restricting and sifting integral points on affine homogeneous varieties
Gorodnik, Alexander
2010-01-01
In a previous paper {GN2} an effective solution of the lattice point counting problem in general domains in semisimple S-algebraic groups and affine symmetric varieties was established. The method relies on the mean ergodic theorem for the action of G on G/Gamma, and implies uniformity in counting over families of lattice subgroups admitting a uniform spectral gap. In the present paper we extend some methods developed in {NS} and use them to establish several useful consequences of this property, including : Effective upper bounds on lifting for solutions of congruences in affine homogeneous varieties, effective upper bounds on the number of integral points on general subvarieties of semisimple group varieties, effective lower bounds on the number of almost prime points on symmetric varieties, and effective upper bounds on almost prime solutions of Linnik-type congruence problems in homogeneous varieties.
Reflection symmetry detection using locally affine invariant edge correspondence.
Wang, Zhaozhong; Tang, Zesheng; Zhang, Xiao
2015-04-01
Reflection symmetry detection receives increasing attentions in recent years. The state-of-the-art algorithms mainly use the matching of intensity-based features (such as the SIFT) within a single image to find symmetry axes. This paper proposes a novel approach by establishing the correspondence of locally affine invariant edge-based features, which are superior to the intensity based in the aspects that it is insensitive to illumination variations, and applicable to textureless objects. The locally affine invariance is achieved by simple linear algebra for efficient and robust computations, making the algorithm suitable for detections under object distortions like perspective projection. Commonly used edge detectors and a voting process are, respectively, used before and after the edge description and matching steps to form a complete reflection detection pipeline. Experiments are performed using synthetic and real-world images with both multiple and single reflection symmetry axis. The test results are compared with existing algorithms to validate the proposed method.
Evolution based on chromosome affinity from a network perspective
Monteiro, R. L. S.; Fontoura, J. R. A.; Carneiro, T. K. G.; Moret, M. A.; Pereira, H. B. B.
2014-06-01
Recent studies have focused on models to simulate the complex phenomenon of evolution of species. Several studies have been performed with theoretical models based on Darwin's theories to associate them with the actual evolution of species. However, none of the existing models include the affinity between individuals using network properties. In this paper, we present a new model based on the concept of affinity. The model is used to simulate the evolution of species in an ecosystem composed of individuals and their relationships. We propose an evolutive algorithm that incorporates the degree centrality and efficiency network properties to perform the crossover process and to obtain the network topology objective, respectively. Using a real network as a starting point, we simulate its evolution and compare its results with the results of 5788 computer-generated networks.
Algorithm-Architecture Affinity - Parallelism Changes the Picture
DEFF Research Database (Denmark)
Abildgren, Rasmus; Šaramentovas, Aleksandras; Ruzgys, Paulius;
Reducing the time-to-market factor is a challenge for many embedded systems designers. In that respect, hardwaresoftware partitioning is a key issue which has been studied during the last two decades. In this paper we present an extension to recent works dealing with metrics for guiding...... the hardware-software partitioning step. This extension builds upon and complement our own work with metrics in the Design Trotter project, and is combined with the affinity metric approach. We show that the proposed extension improves the original affinity metric in terms of parallelism detection, and thus...... can help system designers to make wiser hardware-software partitioning decisions, which in turn reduces the time-to-market factor....
Mullerian inhibiting substance fractionation by dye affinity chromatography.
Budzik, G P; Powell, S M; Kamagata, S; Donahoe, P K
1983-08-01
Mullerian inhibiting substance (MIS), a large glycoprotein secreted by the fetal and neonatal testis, is responsible for regression of the Mullerian ducts in the male embryo. This fetal growth regulator has been purified more than 2000-fold from crude testicular incubation medium following fractionation on a triazinyl dye affinity support. A high yield of 60% recovered activity was achieved in the absence of exogenous carrier protein by stabilizing MIS with 2-mercaptoethanol, EDTA, and Nonidet-P40 and eliminating losses in the handling and concentration of MIS fractions. Although affinity elution with nucleotides has proved successful in other systems, MIS could not be eluted with ATP, GTP, or AMP, with or without divalent metal ions. Nucleotide elution, however, does remove contaminating proteins prior to MIS recovery with high ionic strength. The 2000-fold-purified MIS fraction, although not homogeneous, shows a reduction-sensitive band after SDS-gel electrophoresis that has been proposed to be the MIS dimer.
Statistically Appraising Process Quality of Affinity Isolation Experiments
Energy Technology Data Exchange (ETDEWEB)
Sharp, Julia L.; Borkowski, John J.; Schmoyer, Denise A.; Daly, Don S.; Purvine, Samuel O.; Cannon, William R.; Hurst, G. B.
2009-03-15
Quality affinity isolation experiments are necessary to identify valid protein-protein interactions. Biological error, processing error, and random variability can reduce the quality of an experiment, and thus hinder the identification of protein interaction pairs. Appraising affinity isolation assay quality is essential to inferring protein associations. An important step of the assay is the mass spectrometric identification of proteins. To evaluate this step, a known mixture of proteins is processed through a mass spectrometer as a quality control mixture. If the mass spectrometer yields unexpected results, the process is currently qualitatively evaluated, tuned, and reset. Statistical quality control (SQC) procedures, including the use of cumulative sum, the individual measurement, and moving range charts are implemented to analyze the stability of the mass spectrometric analysis. The SQC measures presented here can assist in establishing preliminary control limits to identify an out-of-control process and investigate assignable causes for shifts in the process mean in real-time.
Theoretical Estimate of Hydride Affinities of Aromatic Carbonyl Compounds
Institute of Scientific and Technical Information of China (English)
AI Teng; ZHU Xiao-Qing; CHENG Jin-Pei
2003-01-01
@@ Aromatic carbonyl compounds are one type of the most important organic compounds, and the reductions ofthem by hydride agents such as LiAlH4 or NaBH4 are widely used in organic synthesis. The reactivity of carbonyl compounds generally increases in the following order: ketone ＜ aldehyde, and amide ＜ acid ＜ ester ＜ acid halide, which could be related to their hydride affinities (HA). In the previous paper, Robert[1] calculated the absolute HAof a series of small non-aromatic carbonyl compounds. In this paper, we use DFT method at B3LYP/6-311 + + G (2d, 2p)∥B3LYP/6-31 + G* level to estimate hydride affinities of five groups of aromatic carbonyl compounds. The detailed results are listed in Table 1.
Improved Energy-Momentum Currents in Metric-Affine Spacetime
Hecht, R D; McCrea, J D; Mielke, E W; Ne'eman, Yuval; Hecht, Ralf; Hehl, Friedrich W.; Mielke, Eckehard W.; Ne'eman, Yuval
1992-01-01
In Minkowski spacetime it is well-known that the canonical energy-momentum current is involved in the construction of the globally conserved currents of energy-momentum and total angular momentum. For the construction of conserved currents corresponding to (approximate) scale and proper conformal symmetries, however, an improved energy-momentum current is needed. By extending the Minkowskian framework to a genuine metric-affine spacetime, we find that the affine Noether identities and the conformal Killing equations enforce this improvement in a rather natural way. So far, no gravitational dynamics is involved in our construction. The resulting dilation and proper conformal currents are conserved provided the trace of the energy-momentum current satisfies a (mild) scaling relation or even vanishes.
A novel affinity purification method to isolate peptide specific antibodies
DEFF Research Database (Denmark)
Karlsen, Alan E; Lernmark, A; Kofod, Hans
1990-01-01
Site-specific, high affinity polyclonal antisera are effectively and successfully produced by immunizing rabbits with synthetic peptides. The use of these antisera in subsequent immune analysis is often limited because of non-specific binding. We describe a new and simple method to effectively...... affinity-purify anti-peptide antibodies. To test our system, rabbits were immunized with model peptides representing sequences of the putative rabbit growth hormone receptor and several HLA-DQ beta-chain molecules. Polystyrene plastic beads were coated with peptides. Immune serum was incubated...... with the beads and after a wash step the bound antibodies were eluted in 1 M acetic acid. The eluted material was composed predominantly of intact immunoglobulin as evidenced by the presence of heavy and light chain bands in SDS-PAGE. The eluted antibodies were peptide specific in ELISA and bound only to intact...
Some remarks on regular subgroups of the affine group
Directory of Open Access Journals (Sweden)
M. Chiara Tamburini Bellani
2012-03-01
Full Text Available Let $V$ be a vector space over a field $F$ of characteristic $pgeq 0$ and let $T$ be a regular subgroup of the affine group $AGL(V$. In the finite dimensional case we show that, if $T$ is abelian or $p>0$, then $T$ is unipotent. For $T$ abelian, pushing forward some ideas used in [A. Caranti, F. Dalla Volta and M. Sala, Abelian regular subgroups of the affine group and radical rings, Publ. Math. Debrecen {bf 69} (2006, 297--308.], we show that the set $left{t-Imid tin Tright}$ is a subalgebra of $End_F(Foplus V$, which is nilpotent when $V$ has finite dimension. This allows a rather systematic construction of abelian regular subgroups.
An angular momentum conserving Affine-Particle-In-Cell method
Jiang, Chenfanfu; Teran, Joseph
2016-01-01
We present a new technique for transferring momentum and velocity between particles and grid with Particle-In-Cell (PIC) calculations which we call Affine-Particle-In-Cell (APIC). APIC represents particle velocities as locally affine, rather than locally constant as in traditional PIC. We show that this representation allows APIC to conserve linear and angular momentum across transfers while also dramatically reducing numerical diffusion usually associated with PIC. Notably, conservation is achieved with lumped mass, as opposed to the more commonly used Fluid Implicit Particle (FLIP) transfers which require a 'full' mass matrix for exact conservation. Furthermore, unlike FLIP, APIC retains a filtering property of the original PIC and thus does not accumulate velocity modes on particles as FLIP does. In particular, we demonstrate that APIC does not experience velocity instabilities that are characteristic of FLIP in a number of Material Point Method (MPM) hyperelasticity calculations. Lastly, we demonstrate th...
Bioskin as an affinity matrix for the separation of glycoproteins.
Vicente, C; Sebastián, B; Fontaniella, B; Márquez, A; Xavier Filho, L; Legaz, M E
2001-05-11
Bioskin is a natural product produced by a mixed culture of Acetobacter xylinum, Saccharomyces cerevisiae and S. pombe cultured on media containing sucrose. It is of fibrillar nature able to retain some proteins, such as cytochrome c, by adsorption, and mainly composed of glucosamine and N-acetyl-D-glucosamine. This makes it possible that, at an adequate pH value, proteins charged as polyanionic molecules, such as catalase, can be retained by ionic adsorption using the positively charged amino groups of the matrix. In addition, bioskin can also be used as an affinity matrix to retain glycoproteins able to perform specific affinity reactions with the amino sugars of the matrix, such as invertase, fetuin or ovalbumin. Its possible use as a chromatographic support is discussed.
Analytical theory for shape stiffness
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
The shape stiffness of mill m is defined as the crosswise rigidity of the unit width of steel plate, that is, m=k/b. By differentiating the steel plate crown equation in the vector model of steel plate shape, a new concise equation for the shape stiffness, kc=m+q, is obtained. Furthermore, by combining the calculation equation for steel plate crown derived from Castigliano's theorem, an analytical calculation equation for the shape rigidity of rolled steel plate is derived. The correctness and practicability of the theory for the shape stiffness are demonstrated by comparing the results from the numerical calculation with the practical data of a rolling mill.
Analytical theory for shape stiffness
Institute of Scientific and Technical Information of China (English)
张进之
2000-01-01
The shape stiffness of mill m is defined as the crosswise rigidity of the unit width of steel plate, that is, m = k/b. By differentiating the steel plate crown equation in the vector model of steel plate shape, a new concise equation for the shape stiffness, kc = m + q, is obtained. Furthermore, by combining the calculation equation for steel plate crown derived from Castigliano’s theorem, an analytical calculation equation for the shape rigidity of rolled steel plate is derived. The correctness and practicability of the theory for the shape stiffness are demonstrated by comparing the results from the numerical calculation with the practical data of a rolling mill.
Geometric Topology and Shape Theory
Segal, Jack
1987-01-01
The aim of this international conference the third of its type was to survey recent developments in Geometric Topology and Shape Theory with an emphasis on their interaction. The volume contains original research papers and carefully selected survey of currently active areas. The main topics and themes represented by the papers of this volume include decomposition theory, cell-like mappings and CE-equivalent compacta, covering dimension versus cohomological dimension, ANR's and LCn-compacta, homology manifolds, embeddings of continua into manifolds, complement theorems in shape theory, approximate fibrations and shape fibrations, fibered shape, exact homologies and strong shape theory.
Directory of Open Access Journals (Sweden)
Koki Tsukamoto
2009-01-01
Full Text Available Koki Tsukamoto1, Tatsuya Yoshikawa1,2, Kiyonobu Yokota1, Yuichiro Hourai1, Kazuhiko Fukui11Computational Biology Research Center (CBRC, National Institute of Advanced Industrial Science and Technology (AIST, Koto-ku, Tokyo, Japan; 2Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, Toyonaka, Osaka, JapanAbstract: A system was developed to evaluate and predict the interaction between protein pairs by using the widely used shape complementarity search method as the algorithm for docking simulations between the proteins. We used this system, which we call the affinity evaluation and prediction (AEP system, to evaluate the interaction between 20 protein pairs. The system first executes a “round robin” shape complementarity search of the target protein group, and evaluates the interaction between the complex structures obtained by the search. These complex structures are selected by using a statistical procedure that we developed called ‘grouping’. At a prevalence of 5.0%, our AEP system predicted protein–protein interactions with a 50.0% recall, 55.6% precision, 95.5% accuracy, and an F-measure of 0.526. By optimizing the grouping process, our AEP system successfully predicted 10 protein pairs (among 20 pairs that were biologically relevant combinations. Our ultimate goal is to construct an affinity database that will provide cell biologists and drug designers with crucial information obtained using our AEP system.Keywords: protein–protein interaction, affinity analysis, protein–protein docking, FFT, massive parallel computing
Blanco-Pillado, Jose J; Shlaer, Benjamin
2015-01-01
We analyze the shapes of cosmic string loops found in large-scale simulations of an expanding-universe string network. The simulation does not include gravitational back reaction, but we model that process by smoothing the loop using Lorentzian convolution. We find that loops at formation consist of generally straight segments separated by kinks. We do not see cusps or any cusp-like structure at the scale of the entire loop, although we do see very small regions of string that move with large Lorentz boosts. However, smoothing of the string almost always introduces two cusps on each loop. The smoothing process does not lead to any significant fragmentation of loops that were in non-self-intersecting trajectories before smoothing.
Energy Technology Data Exchange (ETDEWEB)
Schlaffer, Matthias [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Spannowsky, Michael [Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology; Takeuchi, Michihisa [King' s College London (United Kingdom). Theoretical Physics and Cosmology Group; Weiler, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Wymant, Chris [Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology; Laboratoire d' Annecy-le-Vieux de Physique Theorique, Annecy-le-Vieux (France)
2014-05-15
The inclusive Higgs production rate through gluon fusion has been measured to be in agreement with the Standard Model (SM). We show that even if the inclusive Higgs production rate is very SM-like, a precise determination of the boosted Higgs transverse momentum shape offers the opportunity to see effects of natural new physics. These measurements are generically motivated by effective field theory arguments and specifically in extensions of the SM with a natural weak scale, like composite Higgs models and natural supersymmetry. We show in detail how a measurement at high transverse momentum of H→2l+p{sub T} via H→ττ and H→WW{sup *} could be performed and demonstrate that it offers a compelling alternative to the t anti tH channel. We discuss the sensitivity to new physics in the most challenging scenario of an exactly SM-like inclusive Higgs cross-section.
Energy Technology Data Exchange (ETDEWEB)
Schlaffer, Matthias [DESY, Hamburg (Germany); Spannowsky, Michael [Durham University, Department of Physics, Institute for Particle Physics Phenomenology, Durham (United Kingdom); Takeuchi, Michihisa [King' s College London, Theoretical Physics and Cosmology Group, Department of Physics, London (United Kingdom); Weiler, Andreas [DESY, Hamburg (Germany); CERN, Theory Division, Physics Department, Geneva 23 (Switzerland); Wymant, Chris [Durham University, Department of Physics, Institute for Particle Physics Phenomenology, Durham (United Kingdom); Laboratoire d' Annecy-le-Vieux de Physique Theorique, 9 Chemin de Bellevue, 74940, Annecy-le-Vieux (France); Imperial College London, Department of Infectious Disease Epidemiology, London (United Kingdom)
2014-10-15
The inclusive Higgs production rate through gluon fusion has been measured to be in agreement with the Standard Model (SM). We show that even if the inclusive Higgs production rate is very SM-like, a precise determination of the boosted Higgs transverse momentum shape offers the opportunity to see effects of natural new physics. These measurements are generically motivated by effective field theory arguments and specifically in extensions of the SM with a natural weak scale, like composite Higgs models and natural supersymmetry. We show in detail how a measurement at high transverse momentum of H → 2l + p{sub T} via H → ττ and H → WW* could be performed and demonstrate that it offers a compelling alternative to the t anti tH channel. We discuss the sensitivity to newphysics in the most challenging scenario of an exactly SM-like inclusive Higgs cross section. (orig.)
Mercati, Flavio
2014-01-01
Shape Dynamics (SD) is a new theory of gravity that is based on fewer and more fundamental first principles than General Relativity (GR). The most important feature of SD is the replacement of GR's relativity of simultaneity with a more tractable gauge symmetry, namely invariance under spatial conformal transformations. This Tutorial contains both a quick introduction for readers curious about SD and a detailed walk-through of the historical and conceptual motivations for the theory, its logical development from first principles and an in-depth description of its present status. The Tutorial is sufficiently self-contained for an undergrad student with some basic background in General Relativity and Lagrangian/Hamiltonian mechanics. It is intended both as a reference text for students approaching the subject, and as a review article for researchers interested in the theory. This is a first version of the Tutorial, which will be periodically expanded and updated with the latest results.
Magnetic Shape Memory Microactuators
Directory of Open Access Journals (Sweden)
Manfred Kohl
2014-11-01
Full Text Available By introducing smart materials in micro systems technologies, novel smart microactuators and sensors are currently being developed, e.g., for mobile, wearable, and implantable MEMS (Micro-electro-mechanical-system devices. Magnetic shape memory alloys (MSMAs are a promising material system as they show multiple coupling effects as well as large, abrupt changes in their physical properties, e.g., of strain and magnetization, due to a first order phase transformation. For the development of MSMA microactuators, considerable efforts are undertaken to fabricate MSMA foils and films showing similar and just as strong effects compared to their bulk counterparts. Novel MEMS-compatible technologies are being developed to enable their micromachining and integration. This review gives an overview of material properties, engineering issues and fabrication technologies. Selected demonstrators are presented illustrating the wide application potential.
Schlaffer, Matthias; Takeuchi, Michihisa; Weiler, Andreas; Wymant, Chris
2014-01-01
The inclusive Higgs production rate through gluon fusion has been measured to be in agreement with the Standard Model (SM). We show that even if the inclusive Higgs production rate is very SM-like, a precise determination of the boosted Higgs transverse momentum shape offers the opportunity to see effects of natural new physics. These measurements are generically motivated by effective field theory arguments and specifically in extensions of the SM with a natural weak scale, like composite Higgs models and natural supersymmetry. We show in detail how a measurement at high transverse momentum of $H\\to 2\\ell+\\mathbf{p}\\!\\!/_T$ via $H\\to \\tau\\tau$ and $H\\to WW^*$ could be performed and demonstrate that it offers a compelling alternative to the $t\\bar t H$ channel. We discuss the sensitivity to new physics in the most challenging scenario of an exactly SM-like inclusive Higgs cross-section.
Eisen, Herman N
2014-05-01
The antibodies produced initially in response to most antigens are high molecular weight (MW) immunoglobulins (IgM) with low affinity for the antigen, while the antibodies produced later are lower MW classes (e.g., IgG and IgA) with, on average, orders of magnitude higher affinity for that antigen. These changes, often termed affinity maturation, take place largely in small B-cell clusters (germinal center; GC) in lymphoid tissues in which proliferating antigen-stimulated B cells express the highly mutagenic cytidine deaminase that mediates immunoglobulin class-switching and sequence diversification of the immunoglobulin variable domains of antigen-binding receptors on B cells (BCR). Of the large library of BCR-mutated B cells thus rapidly generated, a small minority with affinity-enhancing mutations are selected to survive and differentiate into long-lived antibody-secreting plasma cells and memory B cells. BCRs are also endocytic receptors; they internalize and cleave BCR-bound antigen, yielding peptide-MHC complexes that are recognized by follicular helper T cells. Imperfect correlation between BCR affinity for antigen and cognate T-cell engagement may account for the increasing affinity heterogeneity that accompanies the increasing average affinity of antibodies. Conservation of mechanisms underlying mutation and selection of high-affinity antibodies over the ≈200 million years of evolution separating bird and mammal lineages points to the crucial role of antibody affinity enhancement in adaptive immunity.
Semi-supervised clustering using soft-constraint affinity propagation
Leone, Michele; Weigt, Martin
2007-01-01
Semi-supervised clustering aims at dividing partially labeled data into groups, assigning labels to previously unlabeled points. It uses both the geometrical organization of the data set and the available labels assigned to few points, giving additional information compared to unsupervised clustering methods. In this letter, we present a novel, computationally efficient and statistically robust semi-supervised clustering algorithm based on soft-constraint affinity propagation. The method is successfully tested on artificial and biological benchmark data.
Affinity chromatography purification of cytochrome c binding enzymes.
Azzi, A; Bill, K; Broger, C
1982-01-01
An efficient affinity chromatography procedure for the isolation of mitochondrial cytochrome c oxidase and reductase is described. Saccharomyces cerevisiae cytochrome c was used as a ligand, bound to a thiol-Sepharose 4B gel through cysteine-107. In this way, the site of interaction of cytochrome c with cytochrome oxidase and reductase remained unmodified and available for binding to a number of partner enzymes. The procedure is adequate for the purification of all those proteins having in co...
Pretargeting with the affinity enhancement system for radioimmunotherapy.
Barbet, J; Kraeber-Bodéré, F; Vuillez, J P; Gautherot, E; Rouvier, E; Chatal, J F
1999-06-01
The pretargeting technique referred to as the Affinity Enhancement System (AES) uses bispecific antibodies and radiolabeled bivalent haptens that bind cooperatively to target cells in vivo. Experimental and clinical data demonstrate that AES can deliver large radiation doses to tumor cells with high tumor to normal tissue contrast ratios and long activity residence time in tumors. Preliminary clinical results of radioimmunotherapy of medullary thyroid carcinomas and lung cancers look promising.
PREPARATION OF CHITOSAN COATED METAL AFFINITY CHROMATOGRAPHY ADSORBENT
Institute of Scientific and Technical Information of China (English)
AanTianwei; XuWeijiang; 等
1998-01-01
A new and an inexpensive adsorbent of chitosan coated silica for immobilized metal affinity chromatography(IMAC) was studied.After a double coating,the chitosan coated on silica beads could be up to 53.4mg/g silica beads.When pH>3.8,the metal ligand Cu2+ was chelated on the coated chitosan with a bound capacity of 14.6mg/g chitosan without introducing iminodiacetic acid(IDA).
A pulse radiolysis study on electron affinity of piperonal
Institute of Scientific and Technical Information of China (English)
MA; Jianhua; LIN; Weizhen; WANG; Wenfeng; YAO; Side
2005-01-01
The piperonal electron affinity was studied using pulse radiolysis technique. The electron transfer reaction process between piperonal and anthraquinone-2-sulfate was observed in the pH 7 phosphoric acid salt buffer. The transient absorption spectra of electron transfer reaction between piperonal and anthraquinone-2-sulfate were obtained, and the initial proof of the electron transfer between electron donor and acceptor was provided directly. The one-electron reduction potential of piperonal was determined to be -0.457 V.
The relation of morphology and affinity maturation in germinal centers
Meyer-Hermann, M
2002-01-01
The specific morphology of germinal centers is analyzed in the context of the optimization of the humoral immune response. The relevance of dark and light zones for the affinity maturation process is investigated in the framework of a theoretical model for the germinal center reaction. Especially, it is shown that an intermediate appearance of dark zones in germinal center reactions is advantageous for the process of antibody optimization.
A Poisson-based adaptive affinity propagation clustering for SAGE data.
Tang, DongMing; Zhu, QingXin; Yang, Fan
2010-02-01
Serial analysis of gene expression (SAGE) is a powerful tool to obtain gene expression profiles. Clustering analysis is a valuable technique for analyzing SAGE data. In this paper, we propose an adaptive clustering method for SAGE data analysis, namely, PoissonAPS. The method incorporates a novel clustering algorithm, Affinity Propagation (AP). While AP algorithm has demonstrated good performance on many different data sets, it also faces several limitations. PoissonAPS overcomes the limitations of AP using the clustering validation measure as a cost function of merging and splitting, and as a result, it can automatically cluster SAGE data without user-specified parameters. We evaluated PoissonAPS and compared its performance with other methods on several real life SAGE datasets. The experimental results show that PoissonAPS can produce meaningful and interpretable clusters for SAGE data.
SHAPE selection (SHAPES) enrich for RNA structure signal in SHAPE sequencing-based probing data
DEFF Research Database (Denmark)
Poulsen, Line Dahl; Kielpinski, Lukasz Jan; Salama, Sofie R;
2015-01-01
Selective 2' Hydroxyl Acylation analyzed by Primer Extension (SHAPE) is an accurate method for probing of RNA secondary structure. In existing SHAPE methods, the SHAPE probing signal is normalized to a no-reagent control to correct for the background caused by premature termination of the reverse...
Measurement of the Electron Affinities of Indium and Thallium
Energy Technology Data Exchange (ETDEWEB)
Thompson, J. S.; Carpenter, D. L.; Covington, A. M.; Williams, W. W.; Kvale, T. J.; Seely, D. G.
1999-03-20
The electron affinities of indium and thallium were measured in separate experiments using the laser-photodetachment electron spectroscopy technique. The measurements were performed at the University of Nevada, Reno. Negative ion beams of both indium and thallium were extracted from a cesium-sputter negative ion source, and mass analyzed using a 90{sup o} bending magnet. The negative ion beam of interest was then crossed at 90{sup o} with a photon beam from a cw 25-Watt Ar{sup +} laser. The resulting photoelectrons were energy analyzed with a 160{sup o} spherical-sector spectrometer. The electron affinity of In({sup 2}P{sub 1/2}) was determined to be 0.404 {+-} 0.009 eV and the electron affinity of thallium was determined to be 0.377 {+-} 0.013 eV. The fine-structure splittings in the ground states of the negative ions were also determined. The experimental measurements will be compared to several recent theoretical predictions.
Conformational equilibria and intrinsic affinities define integrin activation.
Li, Jing; Su, Yang; Xia, Wei; Qin, Yan; Humphries, Martin J; Vestweber, Dietmar; Cabañas, Carlos; Lu, Chafen; Springer, Timothy A
2017-03-01
We show that the three conformational states of integrin α5β1 have discrete free energies and define activation by measuring intrinsic affinities for ligand of each state and the equilibria linking them. The 5,000-fold higher affinity of the extended-open state than the bent-closed and extended-closed states demonstrates profound regulation of affinity. Free energy requirements for activation are defined with protein fragments and intact α5β1 On the surface of K562 cells, α5β1 is 99.8% bent-closed. Stabilization of the bent conformation by integrin transmembrane and cytoplasmic domains must be overcome by cellular energy input to stabilize extension. Following extension, headpiece opening is energetically favored. N-glycans and leg domains in each subunit that connect the ligand-binding head to the membrane repel or crowd one another and regulate conformational equilibria in favor of headpiece opening. The results suggest new principles for regulating signaling in the large class of receptors built from extracellular domains in tandem with single-span transmembrane domains.
Synthesis and NMDA receptor affinity of fluorinated dioxadrol analogues.
Banerjee, Ashutosh; Schepmann, Dirk; Wünsch, Bernhard
2010-06-01
A series of dioxadrol analogues with fluorine substituents in position 4 of the piperidine ring has been synthesized and pharmacologically evaluated. The key step in the synthesis was the fluorination of diastereomeric piperidones 6a and 6c as well as diastereomeric alcohols 9a and 9c with DAST. The reaction of the alcohols 9a and 9c took place with inversion of configuration. After removal of the Cbz-protective group, the NMDA receptor affinities of the resulting secondary amines 8a, 8c, 12b, and 12d were investigated in receptor binding studies. It was shown that the like-configuration of the ring junction was crucial for high NMDA receptor affinity. An axially oriented fluorine atom in position 4 led to 2-(2,2-diphenyl-1,3-dioxolan-4-yl)-4-fluoropiperidine (12d, WMS-2517) with a K(i)-value of 27nM. The NMDA receptor affinity of 8c (WMS-2513) with an additional fluorine atom in equatorial 4-position was slightly reduced (K(i)=81 nM). Both fluorinated dioxadrol derivatives 8c and 12d showed high selectivity against sigma(1) and sigma(2) receptors as well as the polyamine binding site of NR2B receptors.
Con A affinity glycoproteomics of normal human liver tissue
Institute of Scientific and Technical Information of China (English)
2007-01-01
In order to establish the novel high throughput, high efficiency and low cost technological platform for the research of N-glycoproteomics, to resolve the significance of characteristic expression profile of glycoprotein and to find the proteins with biological functional importance, the glycoproteins with high-mannose core and the two antennary types were purified and enriched by the Con A affinity chromatography. Con A affinity protein expression profiles of normal human liver tissue were gener- ated by using SDS-PAGE, two-dimensional electrophoresis (2-DE) followed by fast fluorescence stain- ing based on multiplexed proteomics (MP) technology. 301 visible protein spots on the gel were de- tected and 85 of glycoproteins were further successfully identified via peptide mass fingerprinting (PMF) by a matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF- MS/MS) and annotated to IPI databases. Identified glycoproteins definitely take part in the regulation of cell cycle and metabolic processes. The glycosylation sites were predicted with NetNGlyc 1.0 and NetOGlyc 3.1 software, meanwhile they were classified according to the geneontology methods. The construction of Con A affinity glycoprotein database of normal human liver tissue would contribute to the subsequent research.