The person-response function (PRF) relates the probability of an individual's correct answer to the difficulty of items measuring the same latent trait. Local deviations of the observed PRF from the expected PRF indicate person misfit. We discuss two new approaches to investigate person fit. The first approach uses kernel smoothing to estimate continuous PRF estimates. Graphical displays of PRF...

A multiple-circuit high pulse repetition frequency (PRF) pulse generator for the pumping of rare gas halide lasers is reported. With this multiple-circuit design, high PRF can be achieved by the use of existing low PRF thyratron switches and capacitors. A two-circuit pulse generator was constructed, and its performance is described. By means of this pulse generator and a blowdown-type fast tran...

An efficient -1 programmed ribosomal frameshifting (PRF) signal requires an RNA slippery sequence and a downstream RNA stimulator, and the hairpin-type pseudoknot is the most common stimulator. However, a pseudoknot is not sufficient to promote -1 PRF. hTPK-DU177, a pseudoknot derived from human telomerase RNA, shares structural similarities with several -1 PRF pseudoknots and is used to dissec...

Studies using drugs that increase or decrease GABAergic transmission suggest that GABA in the pontine reticular formation (PRF) promotes wakefulness and inhibits rapid eye movement (REM) sleep. Cholinergic transmission in the PRF promotes REM sleep, and levels of endogenous acetylcholine (ACh) in the PRF are significantly greater during REM sleep than during wakefulness or non-REM (NREM) sleep....

Purpose To investigate the relation between optical properties, population receptive fields (pRFs), visual function, and subjectively perceived quality of vision after cataract surgery. Methods The study includes 30 patients who had recently undergone bilateral sequential cataract surgery. We used functional magnetic resonance imaging and pRF modelling methods to assess pRF sizes across visua...

Neurons in the visual cortex process a local region of visual space, but in order to adequately analyze natural images, neurons need to interact. The notion of an ‘‘association field’’ proposes that neurons interact to extract extended contours. Here, we identify the site and properties of contour integration mechanisms. We used functional magnetic resonance imaging (fMRI) and population recept...

BACKGROUND The application of pulsed radiofrequency (PRF) close to the dorsal root ganglia, or peripheral nerves, has been demonstrated to be effective for the treatment of chronic neuropathic pain conditions. The goal of this study was to investigate the analgesic effect of immediate PRF treatment after nerve injury and its possible cellular alterations in the dorsal horn of the spinal cord in...

OBJECTIVE Pulsed radiofrequency (PRF) procedure has been used in clinical practice for the treatment of chronic neuropathic pain conditions without neuronal damage. The purpose of this study was to investigate the changes in pain response and glial expression after the application of PRF on a dorsal root ganglion (DRG) in a neuropathic pain model. DESIGN A neuropathic pain model (14 female Sp...

because of having good performance in cancelling the clutter echoes, pulsed-doppler radar is the best solution in some applications. in this paper a new algorithm for signal design and signal processing in high prf radar is developed. the robust chinese remainder theorem is the basis for estimating the unambiguous ranges in the proposed algorithm. two high prf pulsed-doppler radars are designed...

Aims: The current study aimed to compare bone density means around dental implants covered with one of two platelet rich fibrin preparation protocols (Standard-Platelet Rich Fibrin and Advanced-Platelet Fibrin) using standard intraoral digital periapical radiographs. Materials methods: A total ten male patients an age range 28-51 years participated in this split-mouth clinical study. were divid...