A modular field system for near-surface, vertical profiling of the atmospheric composition in harsh environments using cavity ring-down spectroscopy

Cavity ring-down spectroscopy (CRDS) has allowed for increasingly widespread, in situ observations of trace gases, including the stable isotopic composition of water vapor. However, gathering observations in harsh environments still poses challenges, particularly in regard to observing the small-scale exchanges taking place between the surface and atmosphere. It is especially important to resolve the vertical structure of these processes. We have designed the ISE-CUBE system as a modular CRDS deployment system for profiling stable water isotopes in the surface layer, specifically the lowermost 2 m above the surface. We tested the system during a 2-week field campaign during February–March 2020 in Ny-Ålesund, Svalbard, Norway, with ambient temperatures down to −30 ∘C. The system functioned suitably throughout the campaign, with field periods exhibiting only a marginal increase in isotopic measurement uncertainty (30 %) as compared to optimal laboratory operation. Over the 2 m profiling range, we have been able to measure and resolve gradients on the temporal and spatial scales needed in an Arctic environment.publishedVersio

Entwicklung und Evaluierung eines Stressbewältigungsprogramms für Studierende im Hochschulsetting = Development and evaluation of a stress management program for students

Nicht erst seit den Studierendenprotesten werden die Themen Stress und Belastung an Universitäten mannigfaltig thematisiert. Im Gegensatz zur enormen Bedeutung ist die Anzahl der evaluierten Stresstrainings, die speziell für Studierende entwickelt wurden, bestenfalls überschaubar. Ziel der vorliegenden Studie war es, ein auf die Bedürfnisse der Studierenden zugeschnittenes multimodales Stressbewältigungsprogramm zu entwickeln und auf seine Wirksamkeit zu überprüfen. Die Evaluierung des siebenwöchigen Trainings erfolgte durch ein randomisiertes Wartelisten-Kontrollgruppendesign an 63 Studierenden. Insgesamt zeigt sich eine deutliche Verbesserung (signifikante Interaktion Gruppe*Zeit) bezüglich einer Vielzahl gesundheitsrelevanter Parameter: Stressbelastung, Prüfungsangst, psychosomatische Beschwerden, depressive Symptomatik, Perfektionismus, Selbstwert, Erholungsfähigkeit, Beanspruchungs-Erholungs-Bilanz und Selbstmanagementfähigkeiten/Ressourcen. Zusammenfassend erscheint das Trainingsprogramm, mit seiner innovativen zielgruppenspezifischen Konzeption, als erfolgsversprechender Baustein einer präventiven Gesundheitsförderung im Hochschulsetting

Basic fibroblast growth factor (bFGF) in rodent testis

We have previously described a 30 kDa basic fibroblast growth factor (bFGF)-like protein in rodent testicular homogenates and have shown that pachytene spermatocytes are the sites of predominant immunoreactivity for this bFGF-like protein (Mayerhofer, A., Russell, L.D., Grothe, C., Rudolf, M. and Gratzl, M. (1991) Endocrinology 129, 921–924). We have now addressed the question whether this 30 kDa bFGF-like protein is a large bFGF form and whether it is produced by pachytene spermatocytes. We detected bFGF mRNA in homogenates of isolated mouse spermatocytes (which consisted mainly of pachytene spermatocytes) using S1 nuclease protection assays. As shown by Western blot analyses, the bFGF mRNA in mouse spermatocytes is translated into bFGF of an approximate molecular weight of 30 kDa. Neither bFGF mRNA, nor bFGF itself, was observed in isolated mouse Leydig cells. These results indicate that the immunoreactive bFGF-like protein observed previously in germ cells of the murine testis is identical to bFGF. Thus, germ cells of the testis produce bFGF, which may exert regulatory function in the process of spermatogenesis

Maximal atmospheric neutrino mixing and the small ratio of muon to tau mass

We discuss the problem of the small ratio of muon mass to tau mass in a class of seesaw models where maximal atmospheric neutrino mixing is enforced through a $\mu$--$\tau$ interchange symmetry. We introduce into those models an additional symmetry $T$ such that $m_\mu = 0$ in the case of exact $T$ invariance. The symmetry $T$ may be softly broken in the Higgs potential, and one thus achieves $m_\mu \ll m_\tau$ in a technically natural way. We speculate on a wider applicability of this mechanism.Comment: 10 pages, plain LaTeX, no figures, minor changes, final version for J. Phys.