We masked White's and Benary's brightness illusions and simultaneous contrast with narrowband visual noise and measured detection thresholds and brightness. The noise was either isotropic or orientation filtered. A narrow spatial frequency tuning was found for detection and brightness for every stimulus. A narrow orientation tuning was also found: the strength of the illusions decreased (White ...

The cascade algorithm with mask a and dilation M generates a sequence φ n , n = 1, 2,. .. , by the iterative process φ n (x) = α∈Z s a(α)φ n−1 (Mx − α) x ∈ R s , from a starting function φ 0 , where M is a dilation matrix. A complete characterization is given for the strong convergence of cascade algorithms in Sobolev spaces for the case in which M is isotropic. The results on the convergence o...

Texture enhancement for medical images is the most important technique in medical image diagnosis. This paper introduces a texture enhancement technique for medical images by using fractional differential (FD) masks based on Srivastava-Owa fractional operators. We also construct a 2D isotropic gradient mask based on generalized fractional operators. Texture enhancement performance is measured b...

A gas-phase, room-temperature, plasmaless isotropic etching system has been used for bulk and thin lm silicon etching. A computer controlled multi-chambered etcher is used to provide precisely metered pulses of xenon di uoride (XeF2) gas to the etch chamber. Etch rates as high as 15 microns per minute have been observed. The etch appears to have in nite selectivity to many common thin lms, incl...

Traditionally, there are two main methods of mask placement during face mask ventilation: one handed (CE) grip and two handed grip (THT). One handed grip is limited by air leaks between mask and patients face on the side opposite to stabilizing hand. Two handed grips provide protection against air leak but require second provider to deliver tidal volumes when using a self inflating bag or anest...

GaAs etch characteristics like etch rate, etch profile sidewall angle, etch surface morphology and selectivity are studied as a function of Inductively Coupled Plasma (ICP) power and Cl2/BCl3 flow rate ratio in ICP at low pressure (<15mTorr) and low RF bias power (<100W) regime to achieve moderate GaAs etch rate with an-isotropic profiles and smooth surface morphology. The low pressure regime e...

BACKGROUND Despite an expected high prevalence of pregnancy-mask in the Negroid tropical environments, only a few women present to the physicians with this condition in Enugu. It is unclear whether this is due to low prevalence or poor awareness of the condition. OBJECTIVES To determine the prevalence, awareness and treatment of pregnancy-mask among Igbo women in Enugu, Nigeria. METHOD The ...

Excellent chemical and physical properties of glass, over a range of operating conditions, make it a preferred material for chemical detection systems in analytical chemistry, biology, and the environmental sciences. However, it is often compromised with SU8, PDMS, or Parylene materials due to the sophisticated mask preparation requirements for wet etching of glass. Here, we report our efforts ...

A phenomenology of isotropic magnetohydrodynamic (MHD) turbulence subject to both rotation and applied magnetic field is presented. It is assumed that the triple correlation decay time is the shortest between the eddy turn-over time and the ones associated to the rotating frequency and the Alfvén wave period. For Pm=1 it leads to four kinds of piecewise spectra, depending on four parameters: in...

the laryngeal mask airway (lma) is an important addition to the anesthetist's equipments. however, its usage may involve some complications. we have encountered an unusual and potentially serious complication using this equipment. a 45-year old man underwent cataract surgery under general anesthesia. after the induction of anesthesia, a size 4 of the reusable classic lma was inserted without an...