691 research outputs found
Quantifying appearance retention in carpets using geometrical local binary patterns
Quality assessment in carpet manufacturing is performed by humans who evaluate the appearance retention (AR) grade on carpet samples. To quantify the AR grades objectively, different research based on computer vision have been developed. Among them Local Binary Pattern (LBP) and its variations has shown promising results. Nevertheless, the requirements of quality assessment on a wide range of carpets have not been met yet. One of the difficulties is to distinguish between consecutive AR grades in carpets. For this, we adopt an extension of LBP called Geometrical Local Binary Patterns (GLBP) that we recently proposed. The basis of GLBP is to evaluate the grey scale differences between adjacent points defined on a path in a neighbourhood. Symmetries of the paths in the GLBPs are evaluated. The proposed technique is compared with an invariant rotational mirror based LBP technique. The results show that the GLBP technique performs better to distinguish consecutive AR grades in carpets
Kinetic Aspects of the Interaction between Ligand and G Protein-Coupled Receptor: The Case of the Adenosine Receptors
Ligandâreceptor binding kinetics is an emerging topic in the drug research community. Over the past years, medicinal chemistry approaches from a kinetic perspective have been increasingly applied to G protein-coupled receptors including the adenosine receptors (AR), which are involved in a plethora of physiological and pathological conditions. The study of ligandâAR binding kinetics offers room for detailed structureâkinetics relationships next to more traditional structureâactivity relationships. Their combination may facilitate the triage of candidate compounds in hit-to-lead campaigns. Furthermore, kinetic studies also help in understanding AR allosterism. Allosteric modulation may yield a change in the activity and conformation of a receptor resulting from the binding of a compound at a site distinct from where the endogenous agonist adenosine binds. Hence, in this Review, we summarize available data and evidence for the binding kinetics of orthosteric and allosteric AR ligands. We hope this Review will raise awareness to consider the kinetic aspects of drugâtarget interactions on both ARs and other drug targets.Medicinal Chemistr
Acclimation responses of gill ionocytes of red tilapia (Oreochromis mossambicus Ă O. niloticus) to water salinity and alkalinity
To understand the acclimation strategies of red tilapia to different environments, this study aimed to evaluate different responses of red tilapia (O. mossambicus Ă O. niloticus) to salinity (10-30â°), alkalinity (1-3 gL^-1 NaHCO3) and salinity and alkalinity (10/1-30/3 â°/gL^-1 NaHCO3) environments. Localization, type, size, and numeration of gill ionocytes were investigated on the same specimens by scanning electron microscopy (SEM) and immunohistochemistry (IHC) with antibodies of Na+/K+-ATPase (NKA), Na+/K+/2Cl-contransporter (NKCC), cystic fibrosis transmembrane conductance regulator (CFTR) and carbonic anhydrase (CA). Ionocytes were only located on filaments conducted by SEM. Four types of ionocytes namely pit, convex, concave and transitory types were determined morphologically by their apical openings of which concave and transitory type were not present in freshwater (FW) and saltwater (SW) fish (10). Both ionocytes size and number increased with elevated stress levels. In comparison to FW, density of ionotypes increased to about 4.75, 3.00 and 3.44 fold in SW (30), AW (3) and S&AW (30/3) respectively. Immunoreactive cells on gill filaments confirmed branchial distribution of ionocytes. Immunoreaction of NKA, NKCC and CA appeared in FW except for CFTR while they all appeared in SW (30), AW (3) and S&AW (30/3)
Bound state solutions of the Dirac-Rosen-Morse potential with spin and pseudospin symmetry
The energy spectra and the corresponding two- component spinor wavefunctions
of the Dirac equation for the Rosen-Morse potential with spin and pseudospin
symmetry are obtained. The wave ( state) solutions for this
problem are obtained by using the basic concept of the supersymmetric quantum
mechanics approach and function analysis (standard approach) in the
calculations. Under the spin symmetry and pseudospin symmetry, the energy
equation and the corresponding two-component spinor wavefunctions for this
potential and other special types of this potential are obtained. Extension of
this result to state is suggested.Comment: 18 page
A progressive refinement approach for the visualisation of implicit surfaces
Visualising implicit surfaces with the ray casting method is a slow procedure. The design cycle of a new implicit surface is, therefore, fraught with long latency times as a user must wait for the surface to be rendered before being able to decide what changes should be introduced in the next iteration. In this paper, we present an attempt at reducing the design cycle of an implicit surface modeler by introducing a progressive refinement rendering approach to the visualisation of implicit surfaces. This progressive refinement renderer provides a quick previewing facility. It first displays a low quality estimate of what the final rendering is going to be and, as the computation progresses, increases the quality of this estimate at a steady rate. The progressive refinement algorithm is based on the adaptive subdivision of the viewing frustrum into smaller cells. An estimate for the variation of the implicit function inside each cell is obtained with an affine arithmetic range estimation technique. Overall, we show that our progressive refinement approach not only provides the user with visual feedback as the rendering advances but is also capable of completing the image faster than a conventional implicit surface rendering algorithm based on ray casting
Magnetic Field Structures in a Facular Region Observed by THEMIS and Hinode
The main objective of this paper is to build and compare vector magnetic maps
obtained by two spectral polarimeters, i.e. THEMIS/MTR and Hinode SOT/SP, using
two inversion codes (UNNOFIT and MELANIE) based on the Milne-Eddington solar
atmosphere model. To this end, we used observations of a facular region within
active region NOAA 10996 on 23 May 2008, and found consistent results
concerning the field strength, azimuth and inclination distributions. Because
SOT/SP is free from the seeing effect and has better spatial resolution, we
were able to resolve small magnetic polarities with sizes of 1" to 2", and we
could detect strong horizontal magnetic fields, which converge or diverge in
negative or positive facular polarities. These findings support models which
suggest the existence of small vertical flux tube bundles in faculae. A new
method is proposed to get the relative formation heights of the multi-lines
observed by MTR assuming the validity of a flux tube model for the faculae. We
found that the Fe 1 6302.5 \AA line forms at a greater atmospheric height than
the Fe 1 5250.2 \AA line.Comment: 20 pages, 9 figures, 3 tables, accepted for publication in Solar
Physic
Study of Thermal Properties of Graphene-Based Structures Using the Force Constant Method
The thermal properties of graphene-based materials are theoretically
investigated. The fourth-nearest neighbor force constant method for phonon
properties is used in conjunction with both the Landauer ballistic and the
non-equilibrium Green's function techniques for transport. Ballistic phonon
transport is investigated for different structures including graphene, graphene
antidot lattices, and graphene nanoribbons. We demonstrate that this particular
methodology is suitable for robust and efficient investigation of phonon
transport in graphene-based devices. This methodology is especially useful for
investigations of thermoelectric and heat transport applications.Comment: 23 pages, 9 figures, 1 tabl
Gravitational Coupling and Dynamical Reduction of The Cosmological Constant
We introduce a dynamical model to reduce a large cosmological constant to a
sufficiently small value. The basic ingredient in this model is a distinction
which has been made between the two unit systems used in cosmology and particle
physics. We have used a conformal invariant gravitational model to define a
particular conformal frame in terms of large scale properties of the universe.
It is then argued that the contributions of mass scales in particle physics to
the vacuum energy density should be considered in a different conformal frame.
In this manner, a decaying mechanism is presented in which the conformal factor
appears as a dynamical field and plays a key role to relax a large effective
cosmological constant. Moreover, we argue that this model also provides a
possible explanation for the coincidence problem.Comment: To appear in GR
Towards a single-chip, implantable RFID system: is a single-cell radio possible?
We present an overview of progress towards single-chip RFID solutions. To date heterogeneous integration has been appropriate for non-biological systems. However, for in-vivo sensors and even drug delivery systems, a small form factor is required. We discuss fundamental limits on the size of the form factor, the effect of the antenna, and propose a unified single-chip RFID solution appropriate for a broad range of biomedical in-vivo device applications, both current and future. Fundamental issues regarding the possibility of single cell RF radios to interface with biological function are discussed
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