A simple dynamic model for eddy currents in a magnetic actuator

This paper presents a simple dynamic model of eddy currents in a magnetic actuator. The model is based on the application of Maxwell's equations to a homogeneous ferromagnetic conductive material. The resulting diffusion equation is solved in two dimensions for a cross-sectional cut through a rectangular bar; boundary conditions are imposed by a sinusoidally varying actuator coil current. The utility of the new modeling approach is illustrated by predicting the dynamic performance of a magnetic bearing actuator. The predictions are found to be in good agreement with measured values. The model provides a new and convenient method of modeling the relationships among voltage, current, force, and flux in magnetic circuits containing eddy currents     

Relation of depression diagnoses to 2-year outcomes in cocaine-dependent patients in a randomized continuing care study.

This study examined the relation between depression diagnoses and outcomes in 132 cocaine-dependent patients who were randomized to relapse prevention (RP) or standard 12-step focused group continuing rare and followed for 2 years. Depressed patients attended more treatment sessions and had more cocaine-free urines during treatment than participants without depression, but they drank alcohol more frequently before treatment and during the 18-month posttreatment follow-up. Cocaine outcomes in depressed patients deteriorated to a greater degree after treatment than did cocaine outcomes in patients without depression, particularly in patients in RP who had a current depressive disorder at baseline. The best alcohol outcomes were obtained in nondepressed patients who received RIP. The results suggest that extended continuing care treatment may be warranted for cocaine-dependent patients with co-occurring depressive disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Vascular MADs: two novel MAD-related genes selectively inducible by flow in human vascular endothelium

Vascular endothelium is an important transducer and integrator of both humoral and biomechanical stimuli within the cardiovascular system. Utilizing a differential display approach, we have identified two genes, Smad6 and Smad7, encoding members of the MAD-related family of molecules, selectively induced in cultured human vascular endothelial cells by steady laminar shear stress, a physiologic fluid mechanical stimulus. MAD-related proteins are a recently identified family of intracellular proteins that are thought to be essential components in the signaling pathways of the serine/threonine kinase receptors of the transforming growth factor beta superfamily. Smad6 and Smad7 possess unique structural features (compared with previously described MADs), and they can physically interact with each other, and, in the case of Smad6, with other known human MAD species, in endothelial cells. Transient expression of Smad6 or Smad7 in vascular endothelial cells inhibits the activation of a transfected reporter gene in response to both TGF-beta and fluid mechanical stimulation. Both Smad6 and Smad7 exhibit a selective pattern of expression in human vascular endothelium in vivo as detected by immunohistochemistry and in situ hybridization. Thus, Smad6 and Smad7 constitute a novel class of MAD-related proteins, termed vascular MADs, that are induced by fluid mechanical forces and can modulate gene expression in response to both humoral and biomechanical stimulation in vascular endothelium.     

Yersinia enterocolitica infection in a 4-month-old infant associated with infection in household dogs

Colon atresia is a rare cause of intestinal obstruction in the neonate and requires early diagnosis and prompt surgical treatment. It is impossible in the neonate to differentiate colon atresia from other forms of obstruction at the time of initial presentation. The diagnosis is confirmed roentgenographically, including views of the abdomen and contrast barium enema series. Lesions proximal to the splenic flexure are treated with initial resection of the atretic segment and a primary anastomosis. Those lesions distal to the splentic flexure are managed initally with a diverting loop colostomy with subsequent staged resection and anastomosis.     

The temporal relation of adherence and alliance to symptom change in cognitive therapy for depression.

This study attempted to replicate an earlier study (R. J. DeRubeis & M. Feeley, 1990) of the prediction of symptom change from process variables in cognitive therapy for depressed outpatients. Measures of in-session therapist behavior and therapist–patient interactions were correlated with prior and subsequent symptom change. One of the positive findings was confirmed, but the other received only marginal support. A "concrete" subset of theory-specified therapist actions, measured early in treatment, predicted subsequent change in depression. The therapeutic alliance was predicted by prior symptom change in 1 of the 2 later assessments, but only at a trend level. Several negative findings were similar to those obtained in the earlier study. Specifically, the alliance, an "abstract" subset of theory-specified therapist actions, and facilitative conditions did not predict subsequent change. Implications for causal inferences in psychotherapy process research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Risk Information Seeking and Processing Model: A Meta‐Analysis

This study relies on state‐of‐the‐art meta‐analytical techniques to assess overall effects of the Risk Information Seeking and Processing (RISP) model. The results support the utility of the RISP model in predicting risk information seeking and systematic processing. However, the model demonstrated limited explanatory power for heuristic processing. A reduced model composed of only 2 variables—current knowledge and informational subjective norms—accounted for a substantial proportion of variance in the outcome variables. This more parsimonious explanation of information seeking and systematic processing might extend the utility of the RISP model to other communication settings not related to risk. Theoretical boundaries of the RISP model and implications for future research are discussed.     

Efficiently building a parse tree from a regular expression

We show in this paper that parsing with regular expressions instead of context-free grammars, when it is possible, is desirable. We present efficient algorithms for performing different tasks that concern parsing: producing the external representation and the internal representation of parse trees; producing all possible parse trees or a single one. Each of our algorithms to produce a parse tree from an input string has an optimal time complexity, linear with the length of the string. Moreover, ambiguous regular expressions can be used. Received: 21 October 1997 / 30 May 2000     

Optimal digital control of a laboratory-scale paper machine headbox

This paper describes the design of a multi-input multi-output (MIMO) digital-linear-quadratic-regulator (DLQR) control system for the headbox of a paper machine. The complete design procedure is described from development of a mathematical model of the nonlinear headbox system, through experimental identification of linear model, to demonstration of closed-loop system performance on a laboratory-scale mock-up of an actual headbox. The important role of computer-aided-design tools is illustrated using Matlab and associated toolboxes. The control algorithm is implemented on a personal computer running the Labtech Notebook control program. The controlled system satisfactorily controls set point changes in total pressure and water level, and rejects disturbances in feedwater pressure. The material presented in the paper is used in a senior level course in digital process control at the University of Idaho. The course is jointly offered by the chemical and electrical engineering departments     

Report of the WHO working group on the assessment of health risks for human infants from exposure to PCDDs, PCDFs and PCBs

On Nov. 20-22, 1995, a World Health Organization working group consisting of 12 scientific representatives from 6 different countries met to reassess the health risks to infants associated with perinatal exposure to polyhalogenated aromatic hydrocarbons (PHAHs). Following a review of previous WHO/EURO consultations, as part of their comprehensive programme on PCDDs, PCDFs and PCBs, current exposure information and recent experimental and epidemiologic data were discussed. Exposure assessments within the past decade have revealed that in the case of breast milk samples concentrations of PCDDs/DFs and PCBs have shown a continual decline, in certain countries by up to 50%. New experimental data has revealed that a variety of structural, functional and behaviourial alterations can be induced in rodent species following exposure to PHAHs while a Dutch collaborative PCB/dioxin study has illustrated subtle clinical, endocrine and mental/psychomotor development effects can occur in breast fed infants. The provisional conclusions of the working group were: 1) current evidence does not warrant altering the previous WHO recommendation for promotion/support of breast feeding and 2) based on new clinical data which supports the biological plausibility of certain observed experimental observations, continued and enhanced effort should be directed towards identifying and controlling sources of environmental input for these contaminants.