Investigation of the comparison method for the dynamic calibration of force transducers

The method of the dynamic calibration of force measuring devices using a force exciter and standard force transducer is discussed, which will also be referred to as the comparison method. To ensure traceability to the definition of force according to Newton's law, the standard force transducer must be calibrated by a direct method. For this purpose, defined inertial forces are generated at the PTB with a shaker and a load mass.     

Waxing and waning in concert: Dynamic comorbidity of conduct disorder with other disruptive and emotional problems over 17 years among clinic-referred boys.

Six waves of structured diagnostic assessments were conducted of 168 clinic-referred 7- to 12-year-olds, over 7 years. Wave-to-wave changes in the number of conduct disorder (CD) behaviors were paralleled by correlated changes in the numbers of symptoms of oppositional defiant disorder (ODD), attention-deficit/hyperactivity disorder (ADHD), depression, and anxiety. In addition, CD in Wave 1 predicted levels of ODD, ADHD, depression, and anxiety in later waves when initial levels of those symptoms were controlled, but only ODD in Wave I predicted CD in later waves when initial CD levels were controlled. These findings indicate a striking degree of dynamic comorbidity between CD and other types of psychopathology and provide an initial empirical framework for needed developmental models of comorbidity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological indexes of a partial frontal syndrome in patients with nonfrontal gliomas.

33 brain tumor patients (aged 26–74 yrs) were investigated with quantitative and qualitative neuropsychological assessments, systematic behavioral observations, and recordings of regional cerebral blood (rCBF). Ss with supratentorial highly malignant gliomas showed severe disturbances of attention, lack of control over premotor and executive functions, distractibility, a deficient abstract attitude, a loss of speech initiative, and diminished speech production. Such impairments are associated with functions of the frontal lobe system and may be related to frontal functional cortical changes as mirrored by rCBF. Signs of frontal dysfunction were seen in Ss with nonfrontal tumors and may suggest frontal lobe diaschisis in patients with Grade III–IV astrocytomas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Die anodische oxydation des p-Methoxystyrols an der ring-scheibenelektrode in abhängigkeit von der pyridin-konzentration

The chemical reactions following the anodic formation of PMOS monocations in the presence of varying concentrations of pyridine were investigated using the ring-disc electrode. In the absence of pyridine a cathodic proton-wave was observed at the ring. This wave decreased to the same extent as the more cathodic pyridinium wave increased with increasing pyridine content. On further raising the pyridine concentration of the solvent the pyridinium wave at the ring began to disappear. At this point the first anodic PMOS wave at the disc started rising. This means that the reaction between pyridine and the protons formed by monocation decomposition is faster than the reaction between pyridine and radical cations. On further increasing the pyridine content the proton formation becomes slower than the pyridine complexation. 3,4-dimethoxypropenylbenzene behaved similarly and pyridine could be replaced by quinilone. The non-dependence of the height of the waves on rate of rotation showed that all reactions are very fast. The observation that a pyridine content which was less than equimolar sufficed to cause the proton wave to disappear may be shown to be due to the geometry of the ring-disc electrode and follows from an elementary relation for this arrangement.     

Untersuchungen über wirkungsmechanismen von lichtschutzmitteln. 1. mitteilung

From mechanistic considerations upon the probability of quenching-processes in the polymer matrix, it was concluded that there exists the possibility of a singlet oxygen mechanism occuring in the photodegradation of polypropylene. Using the sensitized photooxidation of rubrene, it was shown that compounds known to be light stabilizers are able to deactivate, to a greater or lesser extent, singlet oxygen. It is, therefore, not to be excluded that singlet oxygen plays also a role in the photooxidation of polymers. On the other hand, further experiments have shown that these same compounds can also act as radical scavengers or as hydroperoxide-deactivators.     

The roles of feature-specific task set and bottom-up salience in attentional capture: An ERP study.

We investigated the roles of top-down task set and bottom-up stimulus salience for feature-specific attentional capture. Spatially nonpredictive cues preceded search arrays that included a color-defined target. For target-color singleton cues, behavioral spatial cueing effects were accompanied by cue-induced N2pc components, indicative of attentional capture. These effects were only minimally attenuated for nonsingleton target-color cues, underlining the dominance of top-down task set over salience in attentional capture. Nontarget-color singleton cues triggered no N2pc, but instead an anterior N2 component indicative of top-down inhibition. In Experiment 2, inverted behavioral cueing effects of these cues were accompanied by a delayed N2pc to targets at cued locations, suggesting that perceptually salient but task-irrelevant visual events trigger location-specific inhibition mechanisms that can delay subsequent target selection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Group Cohesion, Attitude Projection, and Opinion Certainty: Beyond Interaction.

This experiment investigated the effects of group cohesiveness and estimations of consensus on opinion certainty. Members of high- or low-cohesive groups indicated their own attitude positions on 6 civic issues in a context removed from the task-oriented situation in which the groups were developed. Each person then estimated the positions of in-group or out-group members or participated in a no-projection control condition. As expected, estimation of the attitudes of either target group conferred opinion certainty onto cohesive members compared with levels found in the no-projection condition or among low-cohesive participants. Furthermore, perceptions that coworker input was facilitated and encouraged during group development mediated the effect of the experimental manipulation of cohesion on opinion certainty following attitude projection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Overexpression of the p53 gene in primary and metastatic head and neck carcinomas

The p53 gene has been correlated with disease progression in a number of human malignancies, and p53 abnormalities are found in a high percentage of head and neck squamous cell carcinomas. The objectives of this study were 1. to correlate p53 expression with disease progression in squamous cell carcinoma of the head and neck (SCCHN), and 2. to determine whether there are site-specific differences in p53 expression. Primary lesions and/or lymph node metastases from 147 patients with invasive SCCHN were immunostained for p53 overexpression. Expression of p53 was similar (42% versus 43%) in primary lesions and lymph node metastases. Expression also did not vary significantly by site in the head and neck. In conclusion, increased p53 expression did not correlate with disease progression in our series of patients with invasive SCCHN. The finding of a lack of increased expression with disease spread to lymph nodes supports the belief that p53 alterations occur early in head and neck carcinogenesis.