Study of the parameters affecting contact performance of high reliability relays

Parameters affecting contact performance of high reliability relay

Bending the power law: A CMPL theory of strategy shifts and the automatization of cognitive skills

The shift with practice from use of generic, multistep problem-solving strategies to fast and relatively effortless memory-based strategies, was explored in 2 experiments using pseudoarithmetic tasks. A complete transition to the memory strategy occurred by about the 60th exposure to each problem. The power law of practice did not hold in the overall data for either the mean or the standard deviation of response latency, but it did hold within each strategy (algorithm or retrieval). Learning was highly specific to the practiced problems. These results constitute the 1st clear demonstration of a skill for which the power law does not apply overall. The results do not support the instance theory of automatization (G. D. Logan, 1988) but are consistent with an alternative component 12ower laws (CMPL) theory that assumes that because of intrinsic attentional limitations, only 1 strategy can be executed at a time. One of the fundamental processes of human skill acquisition is the strategy shift with practice from use of generic, multistep procedures to direct retrieval of answers fro

Partial Reinforcement and Generalization

Introduction: The present investigation was designed to study the interaction of two experimentally established parameters of a habit; partial reinforcement and stimulus generalization. Studies concerning the effects of partial reinforcement have occupied a prominent place in the psychological literature since Skinner\u27s (1938) first major treatment of schedules of reinforcement. Numerous stimulus generalization experiments have been reported since Pavlov\u27s (1927) recognition of the generalization phenomenon. The present study explored the effects of applying the partial reinforcement parameter in conditioning and the stimulus generalization variable in extinction. More specifically, groups of human subjects were conditioned to a verbal response under different schedules of reinforcement, and the response was extinguished under different degrees of stimulus generalization. This problem evolved from two separate sources; the laboratory and the clinic. The principle of stimulus generalization is of central importance in the understanding of gross human behavior and is an important concept in Pascal\u27s (1956) theory of behavioral change. A number of the parameters of stimulus generalization have been explored by Pascal, Jenkins and their students. Bueno (1955) and Walker (1956) have studied some of the variables which seem to influence the extent of generalization of a habit. Partial reinforcement is believed to be an additional important parameter of generalization, and this study can be considered a part of an experimental program

Legacies of Wartime Order: Punishment Attacks and Social Control in Northern Ireland

Many armed groups create informal institutions to maintain social order during conflict. The remnants of these informal institutions form a key challenge for governments in postconflict societies in their attempts to reestablish themselves as credible state authorities. The persistence of paramilitary groups’ informal “justice” systems in the form of so-called punishment attacks in Northern Ireland, more than twenty years on from the Good Friday Agreement, offers insights into the legacy of wartime institutions. We argue that armed actors can benefit from the social control wartime institutions grant them long after the conflict ends and both armed actors and civilians are socialized into relying on these institutions. Building on research on wartime institutions, criminal governance, and postwar state-building, we examine how the informal “justice” systems created during the Troubles (1968–98) remain at the fringes of postwar society, drawing on historical works, interviews with stakeholders, geocoded data on “punishment attacks,” and survey data

A covariant formalism of spin precession with respect to a reference congruence

We derive an effectively three-dimensional relativistic spin precession formalism. The formalism is applicable to any spacetime where an arbitrary timelike reference congruence of worldlines is specified. We employ what we call a stopped spin vector which is the spin vector that we would get if we momentarily make a pure boost of the spin vector to stop it relative to the congruence. Starting from the Fermi transport equation for the standard spin vector we derive a corresponding transport equation for the stopped spin vector. Employing a spacetime transport equation for a vector along a worldline, corresponding to spatial parallel transport with respect to the congruence, we can write down a precession formula for a gyroscope relative to the local spatial geometry defined by the congruence. This general approach has already been pursued by Jantzen et. al. (see e.g. Jantzen, Carini and Bini, Ann. Phys. 215 (1997) 1), but the algebraic form of our respective expressions differ. We are also applying the formalism to a novel type of spatial parallel transport introduced in Jonsson (Class. Quantum Grav. 23 (2006) 1), as well as verifying the validity of the intuitive approach of a forthcoming paper (Jonsson, Am. Journ. Phys. 75 (2007) 463) where gyroscope precession is explained entirely as a double Thomas type of effect. We also present the resulting formalism in explicit three-dimensional form (using the boldface vector notation), and give examples of applications.Comment: 27 pages, 8 figure

Low plasma cefepime levels in critically ill septic patients: pharmacokinetic modelling indicates improved troughs with revised dosing

The pharmacokinetics of a 2-g bolus of cefepime were measured in critically ill patients with normal renal function. Variable and low trough plasma drug concentrations were found, and 8 of 10 patients had levels below the MIC at which 50% of the isolates are inhibited for Pseudomonas aeruginosa. Computer simulations predicted that continuous infusion and shorter dosing intervals would increase trough levels

Screening for Social Determinants of Health to Improve Care in Pediatric Patients with Recurrent Urinary Tract Infections: A Scoping Review

Purpose: To describe what is known about how SDoH screening impacts adherence to treatment in pediatric patients with recurrent UTIs

The effect of inoculum source and fluid shear force on the development of in vitro oral multispecies biofilms

AimsSaliva has been previously used as an inoculum for in vitro oral biofilm studies. However, the microbial community profile of saliva is markedly different from hardâ and softâ tissueâ associated oral biofilms. Here, we investigated the changes in the biofilm architecture and microbial diversity of in vitro oral biofilms developed from saliva, tongue or plaqueâ derived inocula under different salivary shear forces.Methods and ResultsFour inoculum types (saliva, bacteria harvested from the tongue, toothbrush and curetteâ harvested plaque) were collected and pooled. Biofilms (n ⠥ 15) were grown for 20 h in cellâ free human saliva flowing at three different shear forces. Stained biofilms were imaged using a confocal laser scanning microscope. Biomass, thickness and roughness were determined by image analysis and bacterial community composition analysed using Ion Torrent. All developed biofilms showed a significant reduction in observed diversity compared with their respective original inoculum. Shear force altered biofilm architecture of saliva and curetteâ collected plaque and community composition of saliva, tongue and curetteâ harvested plaque.ConclusionsDifferent intraoral inocula served as precursors of in vitro oral polymicrobial biofilms which can be influenced by shear.Significance and Impact of the StudyInoculum selection and shear force are key factors to consider when developing multispecies biofilms within in vitro models.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136333/1/jam13376-sup-0001-FigS1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136333/2/jam13376-sup-0002-TableS1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136333/3/jam13376_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136333/4/jam13376.pd