1,019 research outputs found
Logarithmic mathematical morphology: a new framework adaptive to illumination changes
A new set of mathematical morphology (MM) operators adaptive to illumination
changes caused by variation of exposure time or light intensity is defined
thanks to the Logarithmic Image Processing (LIP) model. This model based on the
physics of acquisition is consistent with human vision. The fundamental
operators, the logarithmic-dilation and the logarithmic-erosion, are defined
with the LIP-addition of a structuring function. The combination of these two
adjunct operators gives morphological filters, namely the logarithmic-opening
and closing, useful for pattern recognition. The mathematical relation existing
between ``classical'' dilation and erosion and their logarithmic-versions is
established facilitating their implementation. Results on simulated and real
images show that logarithmic-MM is more efficient on low-contrasted information
than ``classical'' MM
Fabrication of one-dimensional Ag/multiwalled carbon nanotube nano-composite
Composite made of multiwalled carbon nanotubes coated with silver was fabricated by an electroless deposition process. The thickness of silver layer is about 40 to 60 nm, characterized as nano-crystalline with (111) crystal orientation along the nanotube's axial direction. The characterization of silver/carbon nanotube [Ag/CNT] nanowire has shown the large current carrying capability, and the electric conductivity is similar to the pure silver nanowires that Ag/CNT would be promising as building blocks for integrated circuits
Synthesis and Application of Carbon–Iron Oxide Microspheres’ Black Pigments in Electrophoretic Displays
Carbon–iron oxide microspheres’ black pigments (CIOMBs) had been prepared via ultrasonic spray pyrolysis of aqueous solutions containing ferrous chloride and glucose. Due to the presence of carbon, CIOMBs not only exhibited remarkably acid resistance, but also could be well dispersed in both polar solvents and nonpolar solvent. Finally, dispersions of hollow CIOMBs in tetrachloroethylene had successfully been applied in electrophoretic displays
Monodisperse Hollow Tricolor Pigment Particles for Electronic Paper
A general approach has been designed to blue, green, and red pigments by metal ions doping hollow TiO 2. The reaction involves initial formation of PS at TiO2 core–shell nanoparticles via a mixed-solvent method, and then mixing with metal ions solution containing PEG, followed calcining in the atmosphere. The as-prepared hollow pigments exhibit uniform size, bright color, and tunable density, which are fit for electronic paper display
Accuracy of epidemiological inferences based on publicly available information: retrospective comparative analysis of line lists of human cases infected with influenza A(H7N9) in China
published_or_final_versio
Interaction of hnRNPA1/A2 and DAZAP1 with an Alu-Derived Intronic Splicing Enhancer Regulates ATM Aberrant Splicing
We have previously identified an Alu-derived Intronic Splicing enhancer (ISE) in the Ataxia Teleangectasia Mutated gene (ATM) that facilitates intron pre-mRNA processing and leads to the inclusion of a cryptic exon in the final mRNA transcript. By using an RNA pull-down assay, we show here that hnRNPA1/A2, HuR and DAZAP1 splicing factors and DHX36 RNA helicase bind to the ISE. By functional studies (overexpression and siRNA experiments), we demonstrate that hnRNPA1 and DAZAP1 are indeed involved in ISE-dependent ATM cryptic exon activation, with hnRNPA1 acting negatively and DAZAP1 positively on splicing selection. On the contrary, HuR and DHX36 have no effect on ATM splicing pattern. These data suggest that splicing factors with both negative and positive effect can assemble on the intronic Alu repeats and regulate pre-mRNA splicing
Three little pieces for computer and relativity
Numerical relativity has made big strides over the last decade. A number of
problems that have plagued the field for years have now been mostly solved.
This progress has transformed numerical relativity into a powerful tool to
explore fundamental problems in physics and astrophysics, and I present here
three representative examples. These "three little pieces" reflect a personal
choice and describe work that I am particularly familiar with. However, many
more examples could be made.Comment: 42 pages, 11 figures. Plenary talk at "Relativity and Gravitation:
100 Years after Einstein in Prague", June 25 - 29, 2012, Prague, Czech
Republic. To appear in the Proceedings (Edition Open Access). Collects
results appeared in journal articles [72,73, 122-124
Transverse electric field–induced deformation of armchair single-walled carbon nanotube
The deformation of armchair single-walled carbon nanotube under transverse electric field has been investigated using density functional theory. The results show that the circular cross-sections of the nanotubes are deformed to elliptic ones, in which the tube diameter along the field direction is increased, whereas the diameter perpendicular to the field direction is reduced. The electronic structures of the deformed nanotubes were also studied. The ratio of the major diameter to the minor diameter of the elliptic cross-section was used to estimate the degree of the deformation. It is found that this ratio depends on the field strength and the tube diameter. However, the field direction has little role in the deformation
Mechanical Properties of Silicon Nanowires
Nanowires have been taken much attention as a nanoscale building block, which can perform the excellent mechanical function as an electromechanical device. Here, we have performed atomic force microscope (AFM)-based nanoindentation experiments of silicon nanowires in order to investigate the mechanical properties of silicon nanowires. It is shown that stiffness of nanowires is well described by Hertz theory and that elastic modulus of silicon nanowires with various diameters from ~100 to ~600 nm is close to that of bulk silicon. This implies that the elastic modulus of silicon nanowires is independent of their diameters if the diameter is larger than 100 nm. This supports that finite size effect (due to surface effect) does not play a role on elastic behavior of silicon nanowires with diameter of >100 nm
An Atomic-resolution nanomechanical mass sensor
Mechanical resonators are widely used as inertial balances to detect small
quantities of adsorbed mass through shifts in oscillation frequency[1].
Advances in lithography and materials synthesis have enabled the fabrication of
nanoscale mechanical resonators[2, 3, 4, 5, 6], which have been operated as
precision force[7], position[8, 9] and mass sensors[10, 11, 12, 13, 14, 15].
Here we demonstrate a room-temperature, carbon-nanotube-based nanomechanical
resonator with atomic mass resolution. This device is essentially a mass
spectrometer with a mass sensitivity of 1.3 times 10^-25 kg Hz^-1/2 or,
equivalently, 0.40 gold atoms Hz^-1/2. Using this extreme mass sensitivity, we
observe atomic mass shot noise, which is analogous to the electronic shot
noise[16, 17] measured in many semiconductor experiments. Unlike traditional
mass spectrometers, nanomechanical mass spectrometers do not require the
potentially destructive ionization of the test sample, are more sensitive to
large molecules, and could eventually be incorporated on a chip
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