W. 1994. Peroxidase and chitinase isoenzyme activities during root infection of Chinese cabbage with Plasmodiophora brassicae. -Physioi. Plant. 90: 661-670.Roots of two Chinese cabbage (Brassica campestris L. ssp. pekinensts) varieties, one tolerant and one susceptible, were inoculated with Plasmodiophora brassicae in liquid medium and in soil. Chitina.se and peroxidase activities were determined in roots and shoots 1-21 days after inoculation with resting .spores of Plasmodiophora and the enzyme activities compared with healthy tissue of the same age. In infected roots of the susceptible variety 'Granat" chitinase activity was higher than in the control 10 days after inoculation w ith spores. In the tolerant variety "Parkin' we detected an increase in chitinase activity at the same time, which was about twice that of 'Granat'. Chitinase activity in 'Granat' was also enhanced on day 13, 14 and 17 after inoculation, whereas chitinase activity in 'Parkin' was lower in the infected roots than in the controls during that period. In the shoots no correlation between chitinase activity and infection in the two varieties was observ'ed. Chitinase from Chinese cabbage was further characterized and showed a pH optimum at pH 4.5-5.5 and a temperature optimum at 35^5°C. After isoelectric focusing 7 isoenzymes were discovered, but there were almost no differences between infected and healthy root extracts. Two isoenzymes with pi 8.7 and 8.8 showed cross-reactivity w ith an antiserum against bean chitinases. The molecular mass of these isoenzymes was determined as 33 kDa. Total peroxidase activity was generally higher in root tissue of both varieties than in the shoots. Peroxidase activity was increased most prominently in infected "Granat' roots on day 13 after inoculation and of hoth varieties on day 17 compared to the controls, ln clubbed tis.sue of 'Granat' a specific peroxidase isoenzyme appeared the first time 21 days after inoculation and was most prominent 28-30 days after inoculation. This isoenzyme had a molecular mass of ca 24 kDa and a pi of ca 8.8. With respect to our results the strategy of the Plasmodiophorales for plant attack is discussed.

Since the outbreak of the coronavirus disease (COVID-19), face coverings are recommended to diminish person-to-person transmission of the SARS-CoV-2 virus. Some public debates concern claims regarding risks caused by wearing face masks, like, e.g., decreased blood oxygen levels and impaired cognitive capabilities. The present, pre-registered study aims to contribute clarity by delivering a direct comparison of wearing an N95 respirator and wearing no face covering. We focused on a demanding situation to show that cognitive efficacy and individual states are equivalent in both conditions. We conducted a randomized-controlled crossover trial with 44 participants. Participants performed the task while wearing an N95 FFR versus wearing none. We measured physiological (blood oxygen saturation and heart rate variability), behavioral (parameters of performance in the task), and subjective (perceived mental load) data to substantiate our assumption as broadly as possible. We analyzed data regarding both statistical equivalence and differences. All of the investigated dimensions showed statistical equivalence given our pre-registered equivalence boundaries. None of the dimensions showed a significant difference between wearing an FFR and not wearing an FFR.Trial Registration: Preregistered with the Open Science Framework: https://osf.io/c2xp5 (15/11/2020). Retrospectively registered with German Clinical Trials Register: DRKS00024806 (18/03/2021).

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Since the outbreak of the COVID-19 pandemic, the use of face masks is recommended to prevent droplets from traveling from one person to another. A commandment to wear masks applies in most public places to contain the widespread of the virus. Some public debates concern myths regarding risks caused by wearing a mask, like, e.g., decreased blood oxygen levels and impaired cognitive capabilities. The present, pre-registered study aims to contribute clarity by delivering a direct comparison of wearing an FFP2 (N95) respirator and wearing no mask. We focused on a demanding situation to show that cognitive efficacy and the person's state is equivalent in both conditions of a randomized-controlled cross-over study design. We measured physiological (blood oxygen saturation and heart rate variability), behavioral (parameters of performance in the task), and subjective (perceived mental load) data to substantiate our assumption as broad as possible. We analyzed data from 44 participants regarding both statistical equivalence and differences. All of the investigated dimensions showed statistical equivalence given our pre-registered equivalence boundaries. None of the dimensions showed a significant difference between wearing a mask and not wearing a mask.

As working and learning environments become open and flexible, people are also potentially surrounded by ambient noise, which causes an increase in mental workload. The present study uses electroencephalogram (EEG) and subjective measures to investigate if noise-canceling technologies can fade out external distractions and free up mental resources. Therefore, participants had to solve spoken arithmetic tasks that were read out via headphones in three sound environments: a quiet environment (no noise), a noisy environment (noise), and a noisy environment but with active noise-canceling headphones (noise-canceling). Our results of brain activity partially confirm an assumed lower mental load in no noise and noise-canceling compared to noise test condition. The mean P300 activation at Cz resulted in a significant differentiation between the no noise and the other two test conditions. Subjective data indicate an improved situation for the participants when using the noise-canceling technology compared to “normal” headphones but shows no significant discrimination. The present results provide a foundation for further investigations into the relationship between noise-canceling technology and mental workload. Additionally, we give recommendations for an adaptation of the test design for future studies.

Abstract. Mobility research is mainly concerned with understanding mobility on a higher level, including environmental factors, e.g., measuring the time out of home or tracking revisited places. This requires preprocessing the raw data obtained from GPS sensors, like clustering significant locations and distinguishing these from periods on the go. We introduce a new stop and trip detection algorithm to transform a list of position records into intervals of dwelling and transit. The system is based on geometrical analyses of the signal noise: Imperfect GPS data tends to scatter around an actual dwell position in a star-like pattern, and this imperfection is what we leverage for our classification. The system contains four independent classification methods, comparing different aspects of the geometrical properties of a given trajectory. If available, accelerometer readings can be used to improve the system’s accuracy further. To evaluate the classifier’s performance, we recorded a large dataset containing gold-standard labels and compared the classification results of our system with the results of Scikit Mobility and Moving Pandas. Our Stop Go Classifier outperforms the traditional distance/time-threshold-based systems. The described system is available as free software.

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