Detecting and resolving position-dependent temperature effects in real-time quantitative polymerase chain reaction

Real-time quantitative polymerase chain reaction (qPCR) depends on precise temperature control of the sample during cycling. In the current study, we investigated how temperature variation in plate-based qPCR instruments influences qPCR results. Temperature variation was measured by amplicon melting analysis as a convenient means to assess well-to-well differences. Multiple technical replicates of several SYBR Green I-based qPCR assays allowed correlation of relative well temperature to quantification cycle. We found that inadequate template denaturation results in an inverse correlation and requires increasing the denaturation temperature, adding a DNA destabilizing agent, or pretreating with a restriction enzyme. In contrast, inadequate primer annealing results in a direct correlation and requires lowering the annealing temperature. Significant correlations were found in 18 of 25 assays. The critical nature of temperature-dependent effects was shown in a blinded study of 29 patients for the diagnosis of Prader-Willy and Angelman syndromes, where eight diagnoses were incorrect unless temperature-dependent effects were controlled. A method to detect temperature-dependent effects by pairwise comparisons of replicates in routine experiments is presented and applied. Systematic temperature errors in qPCR instruments can be recognized and their effects eliminated when high precision is required in quantitative genetic diagnostics and critical complementary DNA analyses.

Spike-triggered reaction-time EEG as a possible assessment tool for driving ability

The impact of interictal epileptic activity (IEA) on driving is a rarely investigated issue. We analyzed the impact of IEA on reaction time in a pilot study. Reactions to simple visual stimuli (light flash) in the Flash test or complex visual stimuli (obstacle on a road) in a modified car driving computer game, the Steer Clear, were measured during IEA bursts and unremarkable electroencephalography (EEG) periods. Individual epilepsy patients showed slower reaction times (RTs) during generalized IEA compared to RTs during unremarkable EEG periods. RT differences were approximately 300 ms (p < 0.001) in the Flash test and approximately 200 ms (p < 0.001) in the Steer Clear. Prior work suggested that RT differences >100 ms may become clinically relevant. This occurred in 40% of patients in the Flash test and in up to 50% in the Steer Clear. When RT were pooled, mean RT differences were 157 ms in the Flash test (p < 0.0001) and 116 ms in the Steer Clear (p < 0.0001). Generalized IEA of short duration seems to impair brain function, that is, the ability to react. The reaction-time EEG could be used routinely to assess driving ability.

Wahrnehmung und Interpretation von Unterrichtsstörungen aus Schülerperspektive sowie aus Sicht der Lehrpersonen.

The contribution is based on an understanding of teaching as an interaction system that encompasses all parties in the classroom. Social order in classrooms is established through mutual awareness, which includes the perception of classroom disruptions. Using qualitative data, this paper examines the extent to which students’ and teachers’ perspectives coincide with respect to both the perception of classroom disruptions and the teachers’ reaction to discipline disruptions. For this purpose, classrooms were categorized into either infrequent-disruption or frequent-disruption classrooms. The results show, firstly, a high correspondence between teachers’ and students’ perception of classroom disruptions; secondly, a self-serving bias in the teachers’ perception of their own reactions on discipline disruptions; and thirdly, a different interpretation of the term discipline disruption in infrequent- and frequent-disruption classrooms. The possibility that teachers themselves might cause classroom disruptions is discussed. In addition, the concept of classroom management is put into perspective.

Performing AIDS. The Film-maker Rosa von Praunheim between HIV/AIDS-Communities in Germany and the USA

The paper explores the works of German film-maker Rosa von Praunheim during the AIDS crisis, who worked in Germany and the USA in the 1980ies and 1990ies and produced several films portraying the gay communities in both countries in the face of AIDS. The first part of the paper analyses how von Praunheim’s films show different forms of performing community in the two countries. It discusses the filmic techniques utilized to criticize the reaction of the German gay community to the appearance of AIDS and to present Amercian traditions of forming and performing a community as a role model for AIDS-activism. The second part focuses on von Praunheim’s autobiography „40 Years of Perversity. The Sentimental Memoirs of Rosa von Raunheim“ (1993) and the rhetoric strategies he – being HIV-negative himself – uses to become part of New York’s HIV-community. The paper examines the hypothesis that von Praunheim’s rhetoric is constructing and performing a „participative identity“ (Alois Hahn). The paper finally discusses the use and adaption of terms and symbols originating from the context of German National Socialism (e.g. the pink triangle) within the process of forming and performing New York’s AIDS-Community and how they are reused and readapted by Rosa von Praunheim.

Exakte Messung der Zahlungsbereitschaft von Kunden als Erfolgsfaktor des Preismanagements

Stefanie Kisgen, Anne Dresen, Werner G. Faix

Allele-specific polymerase chain reaction diagnostic test for the functional MDR1 polymorphism in dogs

The major multidrug transporter P-glycoprotein (Pgp) contributes to the barrier function of several tissues and organs, including the brain. In a subpopulation of Collies and seven further dog breeds, a 4 base pair deletion has been described in the Pgp-encoding MDR1 gene. This deletion results in the absence of a functional form of Pgp and loss of its protective function. Severe intoxication with the Pgp substrate ivermectin has been attributed to the genetically determined lack of Pgp. An allele-specific polymerase chain reaction (PCR)-based screening method has been developed to detect the mutant allele and to determine if a dog is homozygous or heterozygous for the mutation. Based on this validation, the allele-specific PCR proved to be a robust, reproducible and specific tool, allowing rapid determination of the MDR1 genotype of dogs of at risk breeds using blood samples or buccal swabs.

Rachegefühle und posttraumatische Belastungsreaktionen bei Opfern von Gewalttaten

Theoretischer Hintergrund: Beschreibungen der posttraumatischen Belastungsstörung (PTB) besagen, dass Personen mit PTB häufig starke Rachegefühle erleben. Es besteht jedoch ein Mangel an bestätigenden empirischen Untersuchungen. Fragestellung: Der Zusammenhang zwischen Rachegefühlen und posttraumatischen Belastungsreaktionen wird untersucht. Methode: Die Daten wurden mittels Selbstbeurteilung bei 174 Opfern von Gewalttaten erfasst. Zur Messung der Belastungsreaktionen wurde die Impact of Event-Skala – revidierte Version (IES-R) eingesetzt. Ergebnisse: Rachegefühle korrelieren bedeutsam mit posttraumatischer Intrusion und Übererregung, jedoch nicht mit Vermeidung. Rachegefühle leisten einen Beitrag zur Varianzaufklärung, der über den Vorhersagebeitrag viktimologischer Standardvariablen hinausgeht. Der Zusammenhang wird jedoch erst mit wachsendem zeitlichen Abstand vom Ereignis enger. Schlussfolgerungen: Rachegefühle sind vermutlich als dysfunktionale Bewältigungsreaktion auf erlittene Ungerechtigkeit zu bewerten, jedoch nicht in der ersten Zeit nach einer kriminellen Viktimisierung.