Does psi exist? Lack of replication of an anomalous process of information transfer.

D. J. Bern and C. Honorton (1994) recently presented in this journal a set of ganzfeld extrasensory perception (ESP) experiments conducted by C. Honorton that appeared to support the existence of a communication anomaly. In this article, the authors present a meta analysis of 30 ganzfeld ESP studies from 7 independent laboratories adhering to the same stringent methodological guidelines that C. Honorton followed. The studies failed to confirm his main effect of participants scoring above change on the ESP task, Souffer z?=?0.70, p?=?.24, one-tailed; M effect size (z/N1/2)?=?0.013, SD?=?0.23. The new studies included replication attempts of 3 out of 5 internal effects reported as statistically significant by D. J. Bern and C. Honorton. Only 1 was confirmed, and the authors found the D. J. Bern and C. Honorton were mistaken in describing the original effect as being statistically significant. The authors conclude that the ganzfeld technique does not at present offer a replicable method for producing ESP in the laboratory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Novel diol spiro orthocarbonates derived from glycerol as anti‐shrinkage additives for the cationic photopolymerization of epoxy monomers

Shrinkage that takes place during polymerizations induces internal stress in polymeric materials generating a series of problems like poor adhesion to substrates and delamination in coatings or microcracks and microvoids in composites. Some additives like spiro orthocarbonates can reduce or eliminate this shrinkage. This paper deals with the synthesis of novel diol spiro orthocarbonates (DIOL SOCs) and their effect as anti‐shrinkage additives in the photopolymerization of the monomer 3,4‐epoxycyclohexyl‐3′, 4′‐epoxycyclohexanecarboxylate. It was found that increasing the concentration of the DIOL SOCs resulted in higher conversion of the monomer due to the presence of hydroxyl groups. The viscoelastic properties of the polymer products were also measured. It was observed that at 5 mol% of the mixture of DIOL SOCs there was an increase in the storage modulus due to the crosslinking produced by the bifunctional SOCs. However, at higher concentrations, a decrease in the storage modulus was observed. The level of shrinkage using the DIOL SOCs at 20 mol% was reduced by 45% when compared to the case without any additive. DIOL SOCs can be easily prepared by reacting glycerol with tetraethylorthocarbonate. These additives reduced significantly the level of shrinkage of the polyether derived from the diepoxycyclohexane monomer. Copyright © 2010 Society of Chemical Industry     

Effect of the root canal final rinse protocols on the debris and smear layer removal and on the push‐out strength of an epoxy‐based sealer

The aim of the present study was to evaluate the efficacy of QMiX, SmearClear, and 17% EDTA for the debris and smear layer removal from the root canal and its effects on the push‐out bond strength of an epoxy‐based sealer by scanning electron microscopy (SEM). Forty extracted human canines (n = 10) were assigned to the following final rinse protocols: G1‐distilled water (control), G2–17% EDTA, G3‐SmearClear, and G4‐QMiX. The specimens were submitted to a SEM analysis to evaluate the presence of debris and smear layer, respectively, in the apical or cervical segments. In sequence, forty extracted human maxillary canines with the root canals instrumented were divided into four groups (n = 10) similar to the SEM analysis study. After the filling with AH Plus, the roots were transversally sectioned to obtain dentinal slices. The specimens were submitted to a push‐out bond strength test using an electromechanical testing machine. The statistical analysis for the SEM and push‐out bond strength studies were performed using the Kruskal–Wallis and Dunn tests (α = 5%). There was no difference among the G2, G3, and G4 efficacy in removing the debris and smear layer (P > 0.05). The efficacy of these groups was superior to the control group. The push‐out bond strength values of G2, G3, and G4 were superior to the control group. The ability to remove the debris and smear layer by SmearClear and QMiX was as effective as the 17% EDTA. The final rinse with these solutions promoted similar push‐out bond strength values. Microsc. Res. Tech. 76:533–537, 2013. © 2013 Wiley Periodicals, Inc.     

Demonstrating specific cognitive deficits: A psychometric perspective.

Cognitive deficits associated with psychopathology often do not occur in isolation. Consequently, identifying a specific deficit in a disorder requires comparing the magnitude of group differences on theoretically relevant measures with those on control tasks measuring other constructs. L. J. Chapman and J. P. Chapman (1973) noted that common forms of such Group?×?Task interactions are theoretically ambiguous unless performance measures have comparable discriminating power. The principles of psychometric matching for discriminating power developed in the Chapmans' research program are reviewed, and both criticisms and alternative psychometric approaches are evaluated. Psychometric matching can be mindful of threats to the construct validity of measures and frequently remains methodologically necessary. Otherwise, interactions involving measures that vary in sensitivity to individual differences may be misinterpreted as evidence for specific deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

10-GHz power performance of a type II InP/GaAsSb DHBT

Type-II InP/GaAsSb double heterojunction bipolar transistors (DHBTs) were fabricated and microwave power performance was measured. For an InP collector thickness of 150 nm, the DHBTs show a current gain of 24, low offset voltages, and a BV/sub CEO/>6V. The 1.2/spl times/16 /spl mu/m/sup 2/ devices show f/sub T/=205GHz and f/sub MAX/=106GHz at J/sub C/=304 kA/cm/sup 2/. These devices delivered 12.6 dBm to the load at P/sub AVS/=3.3 dBm operating at 10 GHz, yielding a power-added efficiency of 41% and G/sub T/=9.3 dB.     

A Voltage-Behind-Reactance Synchronous Machine Model With Saturation and Arbitrary Rotor Network Representation

A voltage-behind-reactance formulation of a synchronous machine model is set forth, which incorporates saturation and cross-saturation, and is general enough to encapsulate a variety of rotor structures by use of arbitrary linear networks instead of equivalent circuits. Specifically, the model's equations - originally expressed in the qd-axes framework - are rewritten in such a way as to allow the actual abc stator windings to be represented by inductive branches, which can then be naturally connected in the desired circuit topology, e.g., to a rectifier. The model's predictions are validated against experimental results.     

Irradiation-induced order-to-disorder phase transformation at different temperatures in Dy<Subscript>2</Subscript>O<Subscript>3</Subscript>

Polycrystalline pellets of the rare earth sesquioxide Dy₂O₃ were irradiated at two temperatures (∼120 K and ∼300 K) with 300 keV Kr⁺⁺ ions up to a fluence of 1 × 10²⁰ Kr/m². The crystal structure of the irradiated Dy₂O₃ was observed to change from an ordered cubic bixbyite structure (so-called C-type rare earth sesquioxide structure) to a disordered, anion-deficient fluorite structure. A relatively low ion dose (∼2.5 displacements per atom [dpa]) was sufficient to induce a complete order-to-disorder (O-D) phase transformation at cryogenic temperature (∼120 K) irradiation, while at room temperature (∼300 K) a higher dose (∼25 dpa) produced only a partial O-D phase transformation. Dr. Tang can be reached at Mail-Stop G755.