This paper presents a thorough analysis of the capabilities of the pseudorelevance feedback (PRF) technique applied to Distributed Information Retrieval (DIR). This work emphasizes the effectiveness of PRF applied to the collection fusion problem. Usually, DIR Systems apply PRF in the same way of traditional Information Retrieval systems. For each collection, local results are improved through ...

Programmed -1 ribosomal frameshifting (-1 PRF) has been identified as a mechanism to regulate the expression of many viral genes and some cellular genes. The slippery site of -1 PRF has been well characterized, whereas the +1 PRF signal and the mechanism involved in +1 PRF remain poorly understood. Previous study confirmed that +1 PRF is required for the synthesis of protein products in several...

Abstract Platelet derivatives are commonly used in wound healing and tissue regeneration. Different procedures of platelet preparation may differentially affect growth factor release and cell growth. Preparation of platelet-rich fibrin (PRF) is accompanied by release of growth factors, including platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF) and transforming gr...

West Nile virus (WNV) is a human pathogen of significant medical importance with close to 40,000 cases of encephalitis and more than 1,600 deaths reported in the US alone since its first emergence in New York in 1999. Previous studies identified a motif in the beginning of non-structural gene NS2A of encephalitic flaviviruses including WNV which induces programmed -1 ribosomal frameshift (PRF) ...

RATIONALE Despite undergoing transforaminal epidural steroid injection (TFESI), many patients complain of persisting cervical radicular pain. For the management of chronic cervical radicular pain, clinicians are widely applying pulsed radiofrequency (PRF) stimulation to dorsal root ganglions (DRGs). To enhance the effect of PRF stimulation, we conducted bipolar PRF stimulation in 2 patients wit...

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....