The current state of empirical support for the pharmacological treatment of selective mutism.

This article reviews the current state of evidence for the psychopharmacological treatment of children diagnosed with selective mutism within the context of its link to social anxiety disorder. An increased focus on potential medication treatment for this disorder has resulted from significant monetary and resource limitations in typical practice, parental choice in utilizing treatment from medical personnel, and children who fail to respond to psychosocial interventions. A total of 21 publications within the English literature were located. From these, data for only 57 children between the ages of 4 to 17 years have been reported, with the majority of studies utilizing single-case design or case study methodology. Yet, pharmacological data appear promising for treatment resistant cases of selective mutism. The need for additional research via efficacy/effectiveness methodologies remains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthesis and characterization of layered and scrolled amine-templated vanadium oxides

In order to fully understand the formation mechanism, structure, and role of structural curvature of vanadium oxide nanotubes (VONTs), two isostructural materials (one planar and the other curved)—ethylenediammonium (enH₂) intercalated V₇O₁₆ and vanadium oxide nanourchins (VONUs)—were synthesized and characterized via X-ray diffraction (XRD), electron microscopy, thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy, and magnetic measurements. The synthesis route to (enH₂)V₇O₁₆ is developed using vanadium pentoxide as a starting material and employing pH control. VONUs are synthesized using n-dodecylamine as an amine template for the first time. We demonstrate that the structure of the vanadium oxide layer in these compounds is similar to that of VONTs and their magnetic properties all fit to the same model including the temperature-independent, Curie–Weiss, and spin ½ antiferromagnetic dimer contributions. The vanadium oxidation state in tubular structures appears to be higher than in planar compounds such as (eH₂)V₇O₁₆ and BaV₇O₁₆. The role of the template and vanadium reduction in the formation of nanotubes is discussed.     

Dynamic Functional Unit Assignment for Low Power

A hardware method for functional unit assignment is presented, based on the principle that a functional unit's power consumption is approximated by the switching activity of its inputs. Since computing the Hamming distance of the inputs in hardware is expensive, only a portion of the inputs are examined. Integers often have many identical top bits, due to sign extension, and floating points often have many zeros in the least significant digits, due to the casting of integer values into floating point, and other reasons. The accuracy of these approximations is studied and the results are used to develop a simple, but effective, hardware scheme.     

Physiologic reactivity to startling tones in women with posttraumatic stress disorder.

Autonomic and eyeblink reactivity to startling tones were investigated in women with histories of childhood sexual abuse (CSA). Twenty-one women with current posttraumatic stress disorder (PTSD), 23 with lifetime but not current PTSD, and 13 women who never had PTSD listened to 15 95-dB, 500-ms, 1000-Hz tones with a 0-ms rise time while heart rate (HR), skin conductance (SC), and orbicularis oculi electromyogram (EMG) responses were measured. Participants in the current and lifetime PTSD groups produced larger HR responses across tones and showed slower absolute habituation of SC response magnitude compared with the never PTSD group. EMG response magnitudes did not differ among groups. Women with CSA-related PTSD showed increased autonomic reactivity and slower habituation to high-intensity tones similar to that observed in primarily male, combat PTSD samples. This suggests that heightened autonomic responsivity to startling stimuli in PTSD is not gender or event specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Testing the continuum of delusional beliefs: An experimental study using virtual reality.

A key problem in studying a hypothesized spectrum of severity of delusional ideation is determining that ideas are unfounded. The first objective was to use virtual reality to validate groups of individuals with low, moderate, and high levels of unfounded persecutory ideation. The second objective was to investigate, drawing upon a cognitive model of persecutory delusions, whether clinical and nonclinical paranoia are associated with similar causal factors. Three groups (low paranoia, high nonclinical paranoia, persecutory delusions) of 30 participants were recruited. Levels of paranoia were tested using virtual reality. The groups were compared on assessments of anxiety, worry, interpersonal sensitivity, depression, anomalous perceptual experiences, reasoning, and history of traumatic events. Virtual reality was found to cause no side effects. Persecutory ideation in virtual reality significantly differed across the groups. For the clear majority of the theoretical factors there were dose–response relationships with levels of paranoia. This is consistent with the idea of a spectrum of paranoia in the general population. Persecutory ideation is clearly present outside of clinical groups and there is consistency across the paranoia spectrum in associations with important theoretical variables. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Meta-analyses of safety data: a comparison of exact versus asymptotic methods

The objectives of this study were to establish and describe a database of Cochrane and non-Cochrane meta-analyses of safety data and to determine under what conditions exact methods differ from asymptotic methods in meta-analyses of safety data. A sample of Cochrane (n = 500) and non-Cochrane (n = 200) systematic reviews was randomly selected and a database of safety meta-analyses established. Point estimates and confidence intervals for each meta-analysis were recalculated using exact methods and compared to the results of asymptotic methods. Cochrane reviews were nearly four times as likely as non-Cochrane reviews to contain meta-analyses of safety data (35% compared to 9%). More than 50% of safety meta-analyses contained an outcome with a rare event rate (<5%) and 30% contained at least one study with no events in one arm of the study. For rare event meta-analyses, exact point estimates differed substantially from asymptotic estimates 46% of the time, compared to 17% for those without rare events. Exact confidence intervals differed substantially from asymptotic ones 67% of the time compared to only 19% for those without rare events. The magnitude of differences was also correlated with the number of studies and the summary statistic used to combine the data. Asymptotic methods will not always be a good approximation for exact methods in safety meta-analyses. Event rates and number of studies should be closely examined when choosing the statistical method for combining rare event data.     

Synthesis and Densification of Transparent Magnesium Aluminate Spinel by SPS Processing

Mixtures of elementary oxides, MgO–Al₂O₃, were used to fabricate transparent polycrystalline magnesium aluminate spinel specimens by means of the spark plasma sintering technique. A sintering aid, 1 wt% of LiF, was added to the mixed powder. The presence of the additive promotes the synthesis of spinel that starts at 900°C and is completed at 1100°C. The LiF additive wets spinel on its melting and promotes densification, which is completed at 1600°C. LiF vapor plays a cardinal role in eliminating residual carbon contamination and in the fully dense state, allows attaining a 78% level of optical transmittance. The optimal conditions for achieving adequate transparency were determined and the role of the LiF addition in the various stages of the process is discussed.