Conceptual Design of a High-flux Multi-GeV Gamma-ray Spectrometer.

We present here a novel scheme for the high-resolution spectrometry of high-flux gamma-ray beams with energies per photon in the multi-GeV range. The spectrometer relies on the conversion of the gamma-ray photons into electron-positron pairs in a solid foil with high atomic number. The measured electron and positron spectra are then used to reconstruct the spectrum of the gamma-ray beam. The performance of the spectrometer has been numerically tested against the predicted photon spectra expected from non-linear Compton scattering in the proposed LUXE experiment, showing high fidelity in identifying distinctive features such as Compton edges and non-linearities.

Dual-color high-resolution fiber-FISH analysis on lethal white syndrome carriers in sheep.

Molecular defects occurring in the endothelin receptor type-B (EDNRB) gene are known to be associated with pigmentary anomalies and intestinal aganglionosis in humans, rodents and horses. We carried out a cytogenetic investigation in 2 ewes heterozygous for the deletion of the EDNRB gene and in 2 more females as control. The RBA-banding showed that all 4 ewes were karyologically normal. EDNRB gene-specific probes were produced by PCR and cloning. The application of the R-banding and propidium iodide-staining fluorescent in situ hybridization allowed mapping the gene to OAR 10q22 and confirmed the heterozygous status of the ewes investigated for the EDNRB gene deletion. For the fine estimation of the gene length in sheep and for the correct sizing of the chromosomal gap, a dual-color FISH was applied to high-resolution DNA fibers in combination with digital imaging microscopy. The comparison of the DNA fiber barcodes indicated a chromosomal deletion larger than the EDNRB gene itself. The length of the gene, not known for sheep until now, was estimated to be ∼21 kb, whereas the microchromosomal deletion was ∼100 kb. EDNRB is located in a chromosomal region previously shown to be a fragile site. The applied method allowed locating the potential breakpoints, thus permitting further interesting prospective investigations also in the field of the fragile sites in sheep.

Social cognitions as organizers of autonomic and affective responses to social challenge.

Autonomic and affective responses to children were assessed as a function of adult perceptions of interpersonal control. Women (N = 160) interacted with and provided feedback to computer-simulated children who "behaved" responsively or unresponsively on a computer game. Women were categorized as low in perceived control (PC) if they attributed high control to children but low control to self over negative events on the Parent Attribution Test. As predicted, low-PC women were maximally reactive to child characteristics, manifesting peak levels of defensive arousal (increased level of heart rate and electrodermal activity) and negative affect with unresponsive children and minimal levels of arousal and negative affect with responsive children. Intermediate response levels were shown by high-PC Ss. We interpreted results as suggesting mediating factors that may operate in dysfunctional interaction patterns previously found for low-PC caregivers.

Influences of witnessed affect on information processing in children.

Children between the ages of 5 and 10 years watched a videotape of a child having a routine medical exam. Embedded within the scenes were systematic variations of depicted facial affect shown by doctor and child. Measures were taken of autonomic reactions and information-processing errors in response to positive, neutral, and negative affective cues. For 5-6-year-olds, processing errors were greatest in the negative affect condition. Additionally, peak increases in heart rate (HR) and skin conductance level (SCL) were demonstrated by 5-6-year-olds in response to negative affect shown by the witnessed child; increases in HR were in turn predictive of processing errors. Older children (9-10 years) showed trends reflecting reduced processing errors in response to witnessed negative affect. It was suggested that younger children respond to salient threat cues with a "defensive" response pattern that is relatively adaptive at younger but not older ages.

[Recommendation for a legally valid breath alcohol measurement]. / Vorschlag zur Realisierung einer beweissicheren Atemalkoholmessung.

Evidential breath-alcohol analysis requires measuring devices which cannot yet be obtained from industrial manufacturers. In order to avoid the influence of environment and breath techniques and to relate the breath-alcohol concentration to a standard temperature of 34 degrees C it is necessary to measure the breath temperature with a special device. The required reliability of measured results can only be obtained with two measuring systems operating independently from each other. When two measuring systems of different analytical specificity towards interfering substances are used, the infrared method allows a widely selective determination of ethanol. This is a prerequisite for the legal calibration of breath-alcohol analysers.

[Influence of breath volume on alcohol analysis]. / Einfluss des Atemvolumens auf die Atemalkoholanalyse.

In order to obtain reliable results in breath-alcohol analysis it is necessary to consider alveolar air. In former examinations of the question, which part of expired air contains almost pure alveolar air, a separation between the influence of temperature and volume had not been made. Only after a temperature correction has been performed the influence of volume can clearly be seen in drinking experiments. Measurements undertaken with the ALCOMAT clearly show the influence of varied breathing techniques on the results of breath-alcohol determinations. The demand of a minimum volume in the breath test is not sufficient by itself. In order to get a correct result the expiration volume should be more than 70% of the subject's vital capacity. In case of an expired volume remarkably below 50% of the vital capacity the measured values can be more than 10% below the expected values. Such big deviations can only be the result of a deliberate inspiration and expiration technique of the subject.

[Use of breath alcohol analysis in France]. / Anwendung der Atemalkoholanalyse in Frankreich.

An alcohol legislation concerning the operation of motor vehicles exists in France since 1954. In the meantime the problem of the great number of accidents caused by drivers under the influence of alcohol has required several modifications of the legal regulations. In order to get an effective prevention of alcohol-induced traffic accidents the present and future strategy of the French authorities is mainly based on an intensified application of preliminary and evidential breath-alcohol analysis. The legal limit for breath alcohol was fixed at 0.4 mg/l without a direct reference to the blood alcohol limit.

[The reliability of instruments for measuring breath alcohol]. / Die Zuverlässigkeit von Atemalkoholmessgeräten.

To describe the reliability of breath-alcohol testers, values are measured which characterize precision, accuracy, analytical sensitivity, drift, and hysteresis. The instruments tested were two infrared devices (Alcomat, Alcotest 7110) and one device equipped with a fuel cell (Alcolmeter EBA). Criteria of acceptability are the limits from the first preliminary draft of recommendations by the Organisation Internationale de Métrologie Légale (OIML). The results of measurements clearly show the level of reliability of modern instruments which largely attain the OIML requirements. All measurements were performed with a simulator at 34 degrees C. Therefore the definite influence of breath temperature on the alcohol concentration could be neglected.

P300 and the menstrual cycle.

Event-related potentials (ERPs) were elicited with an auditory discrimination paradigm in 20 adult female subjects on the first day of their menstrual cycles and approximately 14 days later. The amplitude and latency of the N1, P2, N2 and P3 (P300) components were measured for the two assessment times. No differences in either amplitude or latency for any of the components were observed as a function of menstrual cycle. Half the subjects who took oral contraceptives were compared to the other half who did not. No differences or interactions between these subgroups were obtained for any component amplitude or latency. It was concluded that menstrual cycle and use of oral contraceptives do not affect the P3 or other ERP components.