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As the climate continues to warm, a range of feedbacks are expected by the response of vegetation. One of these is the BVOC-aerosol-cloud feedback, initiated by vegetation emitting more biogenic volatile organic compounds (BVOCs) with higher temperature. Once in the atmosphere, these BVOCs are oxidised and can then produce large amounts of biogenic secondary organic aerosols (BSOA) which again cool the surface both directly and through cloud-aerosol interactions (BSOA-aerosol feedback). The strength of this feedback, however, is poorly constrained, with some models suggest it holds significant importance, whereas others suggesting it to be completely negligible.Here, we use two unique long term observational datasets representing the boreal and tropical forests respectively, together with satellite data, to evaluate the BVOC-aerosol-cloud feedback in four ESMs through its chain of processes, using natural variability as a proxy for perturbed states of the climate in both models and observations. We show that the highest modelled feedback in the boreal zone is very likely an overestimate, but also that all the models seem to underestimate the feedback in the tropics. Taking full advantage of the growing number of long-term observational datasets for process evaluation in ESMs shows great promise for pin-pointing areas for model improvement, understanding and constraining variability modelled feedbacks and forcing., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The Bletterbach flora is the most important late Permian (Lopingian) flora of the Southern Alps. The study of a new fossiliferous bed stratigraphically below the cephalopod bed yielded almost 500 plant fossils, 28 of which belong to rare Lopingian plant groups: horsetails, seed ferns and possible cycads. Forty-five other fossils from the collection of Utrecht University were examined. The study of these more than fossils reveals a higher diversity of seed ferns and putative cycadophytes in the Lopingian of Europe than previously documented. Horsetails are represented by dispersed sporophylls, stem fragments and leaf sheaths too badly preserved for attribution to a species. Seed ferns are represented by Sphenopteris and the new genus Germaropteris, which includes G. martinsii (Germar in Kurtze 1839) Kustatscher, Kerp et Van Konijnenburg-van Cittert comb. nov., a species from the German Zechstein formerly assigned to various genera (e.g., Callipteris, Lepidopteris, Peltaspermum). Two species of Sphenopteris (S. suessii, S. sp.) are recorded for the first time from Lopingian strata of the Southern Alps. Remarkable are pinnae with alethopteroid pinnules, because similar forms have not been described from Lopingian deposits of Europe. Putative cycadophytes are represented by two taeniopterid leaves (Taeniopteris sp. A and T. sp. B) and a fragment of a pinnate cycad-like leaf. The Bletterbach flora is one of the most diverse European Lopingian floras, at least with regard to the non-conifer taxa. The floras of the Germanic Zechstein Basin and of the Southern Alps are more similar than previously considered, notwithstanding the vicinity of the latter region to the northern margin of the Palaeotethys; there are no obvious similarities to the floras that occurred along the southern margin of the Palaeotethys. In Europe, plant fossils are generally very rare in Lopingian strata and the presence of plant fossils in the Zechstein Basin and the Southern Alps is apparently related to sea-level changes. They appear to be most common immediately before and after the maximum transgression or sea-level high-stand.

Einleitung: Primäre Risikofaktoren bei Patienten mit differenzierten Schilddrüsenkarzinomen (DTC) sind gut bekannt und im Wesentlichen von der Histologie und dem TNM-Stadium abhängig. In dieser Studie haben wir den Stellenwert des stimulierten Thyreoglobulins (sTg) 6 Monate nach Primärtherapie[for full text, please go to the a.m. URL], 130. Kongress der Deutschen Gesellschaft für Chirurgie

Einleitung: Die Prävalenz einer zervikalen Lymphadenopathie (LAP) bei Patienten mit einer Autoimmunthyreoiditis (AIT) ist unbekannt. Ziel der vorliegenden Studie war die Charakterisierung der LAP bei 6 Patienten mit AIT sowie die Evaluation der Prävalenz einer zervikalen LAP bei Patienten [for full text, please go to the a.m. URL], 130. Kongress der Deutschen Gesellschaft für Chirurgie

For the first time fossil macroscopic remains of charcoal as direct evidence of palaeo-wildfires from the Late Permian Gröden Formation of the Bletterbach-Butterloch area in Northern Italy is described. The charcoal consists of pycnoxylic wood and originates from gymnosperms, but a more specific affiliation is not possible due to the fragmentary nature of the material. On a global scale our knowledge about Late Permian fire-ecology is still rather scarce and this finding helps to fill one of the numerous geographical gaps in our current knowledge about Late Permian wildfires., Rivista italiana di Paleontologia e Stratigrafia, Vol 118, No 2

A new fossiliferous horizon from the famous Bletterbach area is described. The new megafossil locality of late Permian age yields well-preserved plant megafossils, as well as cuticles and in situ pollen. In the flora representatives of the horsetails, seed ferns (Sphenopteris, Lepidopteris, Peltaspermum), putative cycadophytes (two types of Taeniopteris), ginkgophytes (three different leaf types) and conifers (Ortiseia, Pseudovoltzia, Quadrocladus, Pagiophyllum) were distinguished. Remains of doubtful botanical attribution comprise Dicranophyllum-like leaves and Leptostrobus-type of female fructifications as well as permineralized wood and charcoal. Remains of lycophytes reported from the Bletterbach cannot be confirmed. Some of these groups are recorded for the first time from the Bletterbach.

We consider curvature-induced resonances in a planar two-dimensional Dirichlet tube of a width $ d $. It is shown that the distances of the corresponding resonance poles from the real axis are exponentially small as $ d\to 0+ $, provided the curvature of the strip axis satisfies certain analyticity and decay requirements., Comment: LaTeX2.09, 30 pages, 3 figures, to appear in Helv. Phys. Acta