Nomenclatural issues concerning cultured yeasts and other fungi: why it is important to avoid unneeded name changes

The unambiguous application of fungal names is important to communicate scientific findings. Names are critical for (clinical) diagnostics, legal compliance, and regulatory controls, such as biosafety, food security, quarantine regulations, and industrial applications. Consequently, the stability of the taxonomic system and the traceability of nomenclatural changes is crucial for a broad range of users and taxonomists. The unambiguous application of names is assured by the preservation of nomenclatural history and the physical organisms representing a name. Fungi are extremely diverse in terms of ecology, lifestyle, and methods of study. Predominantly unicellular fungi known as yeasts are usually investigated as living cultures. Methods to characterize yeasts include physiological (growth) tests and experiments to induce a sexual morph; both methods require viable cultures. Thus, the preservation and availability of viable reference cultures are important, and cultures representing reference material are cited in species descriptions. Historical surveys revealed drawbacks and inconsistencies between past practices and modern requirements as stated in the International Code of Nomenclature for Algae, Fungi, and Plants (ICNafp). Improper typification of yeasts is a common problem, resulting in a large number invalid yeast species names. With this opinion letter, we address the problem that culturable microorganisms, notably some fungi and algae, require specific provisions under the ICNafp. We use yeasts as a prominent example of fungi known from cultures. But viable type material is important not only for yeasts, but also for other cultivable Fungi that are characterized by particular morphological structures (a specific type of spores), growth properties, and secondary metabolites. We summarize potential proposals which, in our opinion, will improve the stability of fungal names, in particular by protecting those names for which the reference material can be traced back to the original isolate

Current methods for measuring three-phase relative permeability and its influencing factors

Three-phase fluid flow in reservoirs is present in the entire process of oil field development, and three-phase relative permeability data are crucial for reservoir engineering and numerical simulation. At the same time, carbon dioxide flooding and storage have garnered significant attention recently. The calculation of dynamic storage volumes and an in-depth understanding of three-phase flow within formations are inextricably linked to three-phase relative permeability. This review is centered around the available experimental measurements, theoretical models that predict three-phase relative permeability using two-phase data, and four Lattice Boltzmann method models. By analyzing the strengths, weaknesses and limitations of each method and assessing the impact of factors like saturation history, interfacial tension, rock properties, and fluid characteristics on three-phase relative permeability, this paper seeks to offer a comprehensive understanding of the topic. In summary, we provide a concise overview of the prospects and challenges in advancing three-phase relative permeability, serving as a valuable reference for the field of carbon dioxide flooding and storage.Document Type: Invited reviewCited as: Mei, Y., Lv, W., Zhou, X., Huang, J., Jia, N., Wang, G. Current methods for measuring three-phase relative permeability and its influencing factors. Advances in Geo-Energy Research, 2023, 10(1): 21-38. https://doi.org/10.46690/ager.2023.10.0

Barry Smith an sich

Festschrift in Honor of Barry Smith on the occasion of his 65th Birthday. Published as issue 4:4 of the journal Cosmos + Taxis: Studies in Emergent Order and Organization. Includes contributions by Wolfgang Grassl, Nicola Guarino, John T. Kearns, Rudolf Lüthe, Luc Schneider, Peter Simons, Wojciech Żełaniec, and Jan Woleński

An analytical model to predict the effects of suspended solids in injected water on the oil displacement efficiency during waterflooding

Suspended solids in the injection water cause impairment of water injectivity during waterflooding operations. Suspended solids affect reservoir properties and decrease the permeability of reservoir rocks causing an increase of injection pressure and a decrease in water injectivity. Removal of all suspended solids from injection water is an expensive and economically unfeasible process. To minimize the effects of suspended solids to the formation, it is necessary to determine an impairment mechanism of suspended solids on oil displacement and, therefore, optimize the water treatment process. In this paper, an analytical model that describes the relationship between injection water quality and impairment mechanisms on oil displacement is presented. A formation impairment was calculated, introducing the parameter called impairment ratio, which represents the ratio between suspended solids and pore size distribution of reservoir rock. Based on the impairment ratio, decreases in porosity and permeability were calculated with changes in capillary pressure, relative permeability, and displacement efficiency. The model was tested for three different types of injection water. Results indicated the presence of formation impairment even with the smallest particles. Suspended solids had the greatest influence on porosity and permeability impairment. The model could be used as input for reservoir modelling studies for monitoring and controlling displacement efficiency during waterflooding as well as for planning and modification of water treatment units

Mortality of native and invasive ladybirds co-infected by ectoparasitic and entomopathogenic fungi

Harmonia axyridis is an invasive alien ladybird in North America and Europe. Studies show that multiple natural enemies are using Ha. axyridis as a new host. However, thus far, no research has been undertaken to study the effects of simultaneous infection by multiple natural enemies on Ha. axyridis. We hypothesized that high thallus densities of the ectoparasitic fungus Hesperomyces virescens on a ladybird weaken the host's defenses, thereby making it more susceptible to infection by other natural enemies. We examined mortality of the North American-native Olla nu-nigrum and Ha. axyridis co-infected with He. virescens and an entomopathogenic fungus-either Beauveria bassiana or Metarhizium brunneum. Laboratory assays revealed that He. virescens- infected O. nu-nigrum individuals are more susceptible to entomopathogenic fungi, but Ha. axyridis does not suffer the same effects. This is in line with the enemy release hypothesis, which predicts that invasive alien species in new geographic areas experience reduced regulatory effects from natural enemies compared to native species. Considering our results, we can ask how He. virescens affects survival when confronted by other pathogens that previously had little impact on Ha. axyridis

Ectomycorrhizal fungal community assembly on seedlings of a neotropical monodominant tree

Formation of ectomycorrhizae may facilitate early seedling survival of ectomycorrhizal tree species due to enhanced nutrient acquisition. This could be especially important in heavily shaded understories of tropical monodominant forests where host plant photosynthetic capacity is limited. Little information is available on ectomycorrhizal (ECM) fungal colonization or community development of monodominant seedling cohorts, which have high survival rates. Following a 2016 mast seeding event, we sequentially measured percent colonization and species composition of ECM fungi on live and recently dead seedlings of the tropical monodominant tree Dicymbe corymbosa. We also compared seedling ECM fungi to those of nearby adult conspecifics. Ectomycorrhizal fungal communities were remarkably different between seedling age classes, as well as between seedlings and adults. While the /russula-lactarius and /tomentella-thelephora lineages were species-rich throughout, there was 80–90% species turnover between 6- and 12-month-old seedlings. There was no difference in age-class fungal communities across sampling plots, indicating little spatial effect. Fungal colonization extent did not correlate with seedling age or differ markedly between live and dead seedlings. The number of ECM morphotypes increased with seedling age and tended to be greater on live versus dead seedlings. Interspecific competition between ECM fungi or soil nutrient fluxes may influence community assembly of ECM fungi in this tropical monodominant host tree