Einsatz von Chitin als Bodenverbesserungsmittel gegen Pyrenochaeta lycopersici

The severity of infection of tomato plants (cv. De Berao) by Pyrenochaeta lycopersici causing corky root disease was reduced by application of chitin (Biosol) as soil amendment in greenhous-pot experiments. Compared to untreated control plants showing extensive root rot or plants grown in steamed soil, plants treated with chitin showed limited root rot and reached 62% of the average fresh weight of plants grown in steamed soil

Desinfektion von Gemüsesamen mit belüftetem Dampf

Healthy seeds are a necessary condition for economic production of high quality vegetables, not only in organic production. Seed health comprises not just high levels of germination and emergence, but also absence of fungal infections. More than 200 genera of vegetable seed borne pathogenic fungi are listed in the literature: e.g. Alternaria, Ascochyta, Botrytis, Bremia, Cercospora, Colletotrichum, Peronospora, Phoma, Plasmopara, Phytophthora, Stemphylium, Septoria. Hot water seed treatment or hot air treatment can be applied to disinfect vegetable seeds. Both techniques result in an intensive soaking of the seeds, which makes expensive drying necessary to avoid unwanted germination of the grains. Disinfection of carrot seeds with aerated steam (90 sec./65° C.) completely eliminates fungal contaminations without impairing germination percentage. Because of the limited exposure time, little water is taken up by the grains, leading to comparably low drying costs

Mit Dampf zu gesundem Saatgut

Mit Dampf zu gesundem Gemüsesaatgut? Werner E. Heller und Elisabeth Razavi, Forschungsanstalt Agroscope Changins-Wädenswil ACW, 8820 Wädenswil Für das Gelingen jeder Gemüsekultur ist die Gesundheit des Saatgutes von ausschlaggebender Bedeutung. Unter Gesundheit wird eine hohe biologische Qualität, das heisst eine gute Keimfähigkeit und Triebkraft, zusätzlich aber auch die Freiheit von Krankheitserregern verstanden. Es ist aber hinlänglich belegt, dass viele Krankheitserreger von Gemüsekulturen mit dem Saatgut übertragen werden können und dass kontaminiertes Saatgut auf dem Markt angeboten wird. Durch eine Desinfektion mit belüftetem Dampf während einer relativ kurzen Zeitspanne kann beim Saatgut vieler Gemüsearten eine signifikante Reduktion des Kontaminationsgrades mit pathogenen Keimen erreicht werden, ohne dass die Keimfähigkeit wesentlich beeinflusst wird. Wegen der kurzen Behandlungszeit dringt nur wenig Wasser in die Samenkörner ein, was zu einem nur kurzen Nachtrocknungsprozess mit relativ geringen Enegiekosten führt

The impact of lockdown stress and loneliness during the COVID-19 pandemic on mental health among university students in Germany

The COVID-19 pandemic led to a shutdown of universities in Germany. In a longitudinal design, we compared mental health (depression, anxiety, somatic complaints) of university students in Germany before (June to August 2019) and in the course of the COVID-19 pandemic (June 2020) and determined the impact of pandemic-related stress and loneliness on students’ mental health in self-report online surveys. We investigated 443 participants (mean age 22.8 years), among them 77% female, and 10.4% medical students. A small increase of depression mean scores was observed (F(1,420) = 5.21; p = .023), anxiety and somatic complaints have not significantly changed. There was a medium increase in loneliness from pre-pandemic scores to the pandemic situation (F(1,423) = 30.56; p < .001). Analyzed with regression analyses, current loneliness and pre-pandemic distress represented the strongest associations with mental health during the pandemic. Additionally, health-related concerns during the pandemic were associated with symptoms of depression [b = 0.21; 95%CI(0.08; 0.34); t = 3.12; p = .002], anxiety [b = 0.07; 95%CI(0.01; 0.12); t = 2.50; p = .013], somatic complaints [b = 0.33; 95%CI(0.18; 0.47); t = 4.49; p < .001], and loneliness [b = 0.10; 95%CI(0.03; 0.17); t = 2.74; p = .006]. Social stress due to the pandemic situation was associated with loneliness [b = 0.38; 95%CI(0.32; 0.45); t = 11.75; p < .001]. The results imply that university students represent a risk group for psychosocial long-term ramifications of the pandemic

Mental health state and its determinants in German university students across the COVID-19 pandemic : findings from three repeated cross-sectional surveys between 2019 and 2021

Background: Students were at an increased risk for elevated mental symptoms during the first year of the COVID-19 pandemic compared to pre-pandemic levels. As universities remained closed much longer than anticipated, the mental burden was expected to persist through the second year of the pandemic. The current study aimed to investigate the prevalence of mental distress from 2019 through 2021 and identify risk factors for elevated mental burden, focusing on gender. Methods: We analyzed three cross-sectional online surveys among students at the University of Mainz, conducted in 2019 (n = 4,351), 2020 (n = 3,066), and 2021 (n = 1,438). Changes in the prevalence of depressive symptoms, anxiety, suicidal ideation, and loneliness were calculated using Pearson's chi-square tests and analyses of variance. Multiple linear regressions yielded associated risk factors. Results: The proportion of students with clinically relevant depressive symptoms was significantly higher during the pandemic (38.9% in 2020, and 40.7% in 2021), compared to pre-pandemic (29.0% in 2019). Similarly, more students reported suicidal ideation and generalized anxiety during the pandemic with a peak in the second pandemic year (2021). The level of loneliness was significantly higher in 2020, compared to 2019, and remained at a high level in 2021 (p < 0.001, η2p = 0.142). Female and diverse/open gender, being single, living alone, and being a first-year student were identified as risk factors associated with mental burden during the pandemic. Discussion: Mental burdens remained elevated among students through the second year of the pandemic and were associated with socio-demographic risk factors and pandemic-related concerns. Future research should monitor recovery and evaluate the need for psychosocial support

Dynamic masses for the close PG1159 binary SDSSJ212531.92-010745.9

SDSSJ212531.92-010745.9 is the first known PG1159 star in a close binary with a late main sequence companion allowing a dynamical mass determination. The system shows flux variations with a peak-to-peak amplitude of about 0.7 mag and a period of about 6.96h. In August 2007, 13 spectra of SDSSJ212531.92-010745.9 covering the full orbital phase range were taken at the TWIN 3.5m telescope at the Calar Alto Observatory (Alm\'{e}ria, Spain). These confirm the typical PG1159 features seen in the SDSS discovery spectrum, together with the Balmer series of hydrogen in emission (plus other emission lines), interpreted as signature of the companion's irradiated side. A radial velocity curve was obtained for both components. Using co-added radial-velocity-corrected spectra, the spectral analysis of the PG1159 star is being refined. The system's lightcurve, obtained during three seasons of photometry with the G\"ottingen 50cm and T\"ubingen 80cm telescopes, was fitted with both the NIGHTFALL and PHOEBE binary simulation programs. An accurate mass determination of the PG1159 component from the radial velocity measurements requires to first derive the inclination, which requires light curve modelling and yields further constraints on radii, effective temperature and separation of the system's components. From the analysis of all data available so far, we present the possible mass range for the PG1159 component of SDSSJ212531.92-010745.9.Comment: 8 pages, in "White dwarfs", proceedings of the 16th European White Dwarf Workshop, eds. E. Garcia-Berro, M. Hernanz, J. Isern, S. Torres, to be published in J. Phys.: Conf. Se

Antecedents and moderation effects of maladaptive coping behaviors among German university students

Prolonging working hours and presenteeism have been conceptualized as self-endangering coping behaviors in employees, which are related to health impairment. Drawing upon the self-regulation of behavior model, the goal achievement process, and Warr's vitamin model, we examined the antecedents and moderation effects regarding quantitative demands, autonomy, emotion regulation, and self-motivation competence of university students' self-endangering coping behaviors (showing prolonging working hours and presenteeism). Results from a cross-sectional survey of 3,546 German university students indicate that quantitative demands are positively related and autonomy has a u-shape connection with self-endangering coping. Emotion regulation was shown to be a protective factor for prolonging working hours. Moreover, self-motivation moderated the relationship between quantitative demands and prolonging of working hours, but not in the assumed direction. Self-motivation showed a systematic positive relationship with prolonging of working hours, but no relationship with presenteeism. Autonomy moderated the relationship of quantitative demands with both self-endangering behaviors. We found no moderating effects for emotion regulation of quantitative demands or autonomy and self-endangering behaviors. Besides further practical implications, the results suggest that lecturers should design their courses accordingly with less time pressure and university students should be trained in the use of autonomy

Distinct patterns of university students study crafting and the relationships to exhaustion, well-being, and engagement

Job crafting has been established as a bottom-up work design instrument for promoting health and well-being in the workplace. In recent years, the concepts of job crafting have been applied to the university student context, proving to be positively related to student well-being. Building on person-centered analyses from the employment context, we assessed approach study crafting strategy combinations and the relationships to students’ exhaustion, study engagement, and general well-being. Data from 2,882 German university students were examined, collected online during the summer term in 2020. Using latent profile analysis, we found five distinct crafting groups, which showed discriminate validity with regard to emotional exhaustion, engagement, and well-being. The results underscore the positive role of study crafting for students’ health and well-being. They further indicate a less important role of increasing social resources for emotional exhaustion when combined with a moderate increase in structural resources and a moderate increase in challenging demands. Our findings imply that interventions to promote study crafting should be considered to promote student health and well-being

Potential risk groups and psychological, psychosocial, and health behavioral predictors of pharmacological neuroenhancement among university students in Germany

Aiming to develop and implement intervention strategies targeting pharmacological neuroenhancement (PN) among university students more specifically, we (1) assessed the prevalence of PN among German university students, (2) identified potential sociodemographic and study-related risk groups, and (3) investigated sociodemographic, psychological, study-related psychosocial, general psychosocial and health behavior related factors predicting the 12-month prevalence of PN. Therefore, a cross-sectional online survey was administered to students of the University of Mainz, Germany. A binary logistic regression with stepwise inclusion of the five variable groups was performed to predict PN. A total number of 4351 students out of 31,213 registered students (13.9%) participated in the survey, of which N = 3984 answered the question concerning PN. Of these, 10.4% had used one substance for PN at least once in the past 12 months. The regression analysis revealed 13 variables that were significantly related to the 12-month prevalence of PN. Specifically, the group of health behavior related variables showed the strongest relationship with PN. Therefore, an approach to the prevention of PN should be multifactorial so that it addresses social conditions, as well as education on substance use and healthy behaviors in terms of non-pharmacological strategies as alternatives of PN