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Individual plants vary in their ability to respond to environmental changes. The plastic response of a plant enhances its ability to avoid environmental constraints, and hence supports growth, reproduction, and evolutionary and agricultural success.Major progress in the analysis of above- and belowground processes on individual plants has been made by the application of non-invasive imaging methods including Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET).MRI allows for repetitive measurements of roots growing in soil and facilitates quantification of root system architecture traits in 3D. PET, on the other hand, opens a door to analyze dynamic physiological processes in plants such as long-distance carbon transport in a repeatable manner. Combining MRI with PET enables monitoring of short livedCarbon tracer (11C) allocation along the transport paths (i.e. roots visualized by MRI) into active sink structures.To analyse the link between root-internal C allocation patterns and C metabolism in the rhizosphere, we are combining 11CO2 with stable 13CO2 labelling of plants. Isotope ratio mass spectrometry (IRMS) analyses of rhizosphere soil is applied to link root-internal C allocation patterns with distribution of 13C in the rhizosphere soil. The metabolically active rhizosphere organisms are subsequently identified based on DNA 13C stable isotope probing.In our presentation we will highlight our approaches for gathering quantitative data from both image-based technologies in combination with destructive analysis that provides insights into the functioning and dynamics of C transport processes in the plant-soil system.

In 2022, highly pathogenic avian influenza (HPAI) A(H5N1) virus clade 2.3.4.4b became enzootic and caused mass mortality in Sandwich terns and other seabird species across northwestern Europe. We present data on characteristics of the spread of the virus between breeding colonies and the number of dead adult Sandwich terns recorded at breeding sites throughout northwestern Europe. Within two months after the first mortalities were reported, in total 20,531 adult Sandwich terns were found dead, which is >17% of the total northwestern European breeding population. Losses are likely higher, as we expect that many victims were not found (mortality rate might be up to 74% of the breeding population). Inside the colonies almost all chicks died. After the peak of the outbreak, in a colony established by late breeders, 25.7% of adults showed immunity against HPAI subtype H5. Removal of carcasses helped in reducing the spread of the disease and consequently total mortality. More research on the sources and modes of transmission, incubation times, effective containment and immunity is urgently needed to combat this major threat for colonial seabirds.

Background Even with extensive root growth, plants may fail to access subsoil water and nutrients when root-restricting soil layers are present. Biopores, created from decaying roots or soil fauna, reduce penetration resistance and channel root growth into the deeper soil. Further positive effects on plants result from biopore traits, as the pore walls are enriched in nutrients, microbial abundance, and activity relative to bulk soil. However, negative effects on plant growth have also been observed due to root clumping in biopores, less root-soil contact than in the surrounding bulk soil and leaching of nutrients. Scope We discuss methods for biopore research, properties of biopores and their impact plant performance based on a literature review and own data. We elucidate potential implications of altered root-soil contact for plant growth and the consequences of root growth in pores for the rhizosphere microbiome. Conclusions Biopores play an important but ambiguous role in soils. The effects of biopores on plant growth depend on soil properties such as compaction and moisture in an as-yet-unresolved manner. However, pore properties and root-soil contact are key parameters affecting plant yield. Knowledge gaps exist on signaling pathways controlling root growth in pores and on mechanisms modifying rhizosphere properties inside biopores. The degree to which negative effects of biopores on plant growth are compensated in the bulk soil is also unclear. Answering these questions requires interdisciplinary research efforts and novel imaging methods to improve our dynamic understanding of root growth and rhizosphere processes within biopores and at the rhizosphere-biopore interface.

Die Bestimmung des Hörstatus ist tägliche Praxis in phoniatrisch-pädaudiologischen Einrichtungen. Dafür werden in der Regel leitliniengerechte Abläufe bzw. Algorithmen eingesetzt. Für wichtige Patientengruppen wie z.B. mit Hörhilfenversorgung sind in der Literatur [zum vollständigen Text gelangen Sie über die oben angegebene URL]

Propulsion of sperm cells via movement of the flagellum is of vital importance for successful fertilization. While the exact mechanism of energy production for this movement varies between species, in avian species energy is thought to come predominantly from the mitochondria located in the sperm midpiece. Larger midpieces may contain more mitochondria, which should enhance the energetic capacity and possibly promote mobility. Due to an inversion polymorphism on their sex chromosome TguZ, zebra finches (Taeniopygia guttata castanotis) exhibit large within-species variation in sperm midpiece length, and those sperm with the longest midpieces swim the fastest. Here, we test through quantitative real-time PCR in zebra finch ejaculates whether the inversion genotype has an effect on the copy number of mitochondrial DNA. We find that zebra finches carrying the derived allele (correlated with longer sperm midpieces) have more copies of the mitochondrial DNA in their ejaculates than those homozygous for the ancestral allele (shorter midpieces). We suggest downstream effects of mitochondrial DNA copy number variation on the rate of ATP production, which in turn may influence sperm swimming speed and fertilization success. Central components of gamete energy metabolism may thus be the proximate cause for a fitness-relevant genetic polymorphism, stabilizing a megabase-scale inversion at an intermediate allele frequency in the wild.

Meiotic drivers have been proposed as a potent evolutionary force underlying genetic and phenotypic variation, genome structure and also speciation. Due to their strong selective advantage they are expected to rapidly spread through a population despite potentially detrimental effects on organismal fitness. Once fixed, autosomal drivers are cryptic within populations and only become visible in between-population crosses lacking the driver or corresponding suppressor. However, the assumed ubiquity of meiotic drivers has rarely been assessed in crosses between populations or species. Here we test for meiotic drive in hybrid embryos and offspring of Timor and Australian zebra finches — subspecies that have evolved in isolation for about two million years — using 38,541 informative transmissions of 56 markers linked to either centromeres or distal chromosome ends. We did not find evidence for meiotic driver loci on specific chromosomes. However, we observed a weak overall transmission bias towards Timor alleles at centromeres in females (transmission probability of Australian alleles of 47%, nominal P = 6 × 10-5). While this is in line with the centromere drive theory, it goes against the expectation that the subspecies with the larger effective population size (i.e. the Australian zebra finch) should have evolved the more potent meiotic drivers. We thus caution against interpreting our finding as definite evidence for centromeric drive. Yet, weak centromeric meiotic drivers may be more common than generally anticipated and we encourage further studies that are designed to detect also small effect meiotic drivers.

Male reproductive success ultimately depends on the ability of sperm to reach and fertilize the female ova. Thus, selection on sperm characteristics is expected to be strong. Despite this, variation in sperm morphology is often heritable, but causal genetic variants have hitherto not been identified in any species. In zebra finches (Taeniopygia guttata) the relationship between sperm midpiece and flagellum length is non-linear, resulting in a peculiar trimodal distribution of sperm design, which suggests a large genetic effect caused by one or a few loci. Here we show that an inversion on the Z-chromosome explains most of this variation in sperm morphology, and that this inversion has major effects on sperm swimming speed, on male fertility and on within-pair and extra-pair siring success. Males which are homozygous for the derived allele show detrimental sperm characteristics and hence the lowest siring success. However, males that are heterozygous for the inversion have an advantage over males that are homozygous for the ancestral type. These results explain why the derived allele cannot spread to fixation, but has increased to an allele frequency of 40% in the wild. The described genetic effect on sperm design is remarkable in terms of its effect size and represents a rare example of strong heterosis in a natural population. Our results further explain how substantial genetic variation in sperm design can be maintained despite ongoing directional selection.

While topography can infer erosion potential, the practice of conventional agronomic management can trigger accelerated erosion and pose major threats to soil assets such as biodiversity. The majority of farmlands in Upper-Eastern Ghana are moderately hilly and highly susceptible to erosion. This study pioneered the comparative and interactive effects of topography and conventional versus conservation agriculture practices (reduced tillage, main crop and cover crop, crop residue retention vs. removal) in treatments amended with 0, 40, and 80 kg ha−1 N on soil physicochemical properties and microbiota. Topography imposed profound shifts in soil physiochemical properties and prokaryotic community structure. Foot-slope soils harbored higher prokaryotic richness and diversity compared to the up-slope. Bacillaceae (28.95%) and anaerobic bacteria increased in relative abundance in foot-slope soils, while Micrococcaceae (25.79%) gained prominence in up-slope soils. The effect of tillage was significant in foot-slope while crop rotation was influential in up-slope soils on structuring the prokaryotic community. The interactive effect of slope × tillage was significant in altering soil physiochemical properties, but not prokaryotic community structure. Variation in prokaryotic community composition was explained by soil physiochemical properties (14.5%), elevation as a proxy for topography (11.3%), and spatial distance (10.8%), but rather weakly overall by agronomic practices. Among the soil physicochemical properties, pH, clay content, total C%, volumetric water content, temperature, cation exchange capacity, and NO3−-N were relevant factors influencing the soil microbiota. Geomorphic and soil edaphic properties appeared to interact and were the primary triggers of variation in soil microbiota and their responses to the range of agronomic practices that incorporated conservation management outcomes.

Background In salivary-gland-carcinomas (SGC), there is only a small fraction of entities that appears to profit from immune-checkpoint-inhibition (ICI). Recent findings connected the activation of adenosine-signaling with a tolerogenic microenvironment. Therefore, the inhibition of adenosine-pathway markers (CD39 and/or CD73) can augment ICI and/or display a novel immunotherapeutic strategy beyond ICI. Here, we assessed the immunohistochemical expression of CD39 and CD73 across a wide spectrum of SGCs. Methods In total, 114 patients with SGCs consecutively diagnosed between 2001 and 2021 were assessed for clinicopathological baseline-characteristics and underwent confirmatory histopathological review. Immunohistochemical expression-levels of CD39 and CD73 were assessed by applying the tumor-proportion-score (TPS) and the immune-proportional-score (IPS) comparable to PD-L1 expression analysis in routine clinical practice. Additionally, findings were correlated with PD-L1 expression-levels. Results The median age was 60.6 and 51.8% patients were female. The cohort covered a spectrum of eight distinct entities. Advanced-stage disease (UICC/AJCC III/IVA-IVC) at initial diagnosis was present in the majority of patients (64/114). Immunohistochemical-staining revealed positivity for CD39 and CD73 in 48.2% and 21.1% on tumor-cells (TPS ≥ 1%) as well as 46.4% and 42.9% within the immune-cell infiltrate (IPS ≥ 1%), respectively. Further comparative analyses revealed immune-cold entities such adenoidcystic-carcinoma (AdCC), immune-hot tumors such as adenocarcinoma, not otherwise specified (AC (NOS)) and entities with intermediate immunologic features such as acinic-cell-carcinoma (ACC). Conclusion Current results indicate entity-specific adenosine-signaling signatures. These findings suggest that the adenosine-pathway plays a decisive role in tumor immunity among the major spectrum of SGCs. Targeting the adenosine-pathway might pose a promising therapeutic option for selected entities.

When data are not normally distributed (e.g. skewed, zero-inflated, binomial, or count data) researchers are often uncertain whether it may be legitimate to use tests that assume Gaussian errors (e.g. regression, t-test, ANOVA, Gaussian mixed models), or whether one has to either model a more specific error structure or use randomization techniques.Here we use Monte Carlo simulations to explore the pros and cons of fitting Gaussian models to non-normal data in terms of risk of type I error, power and utility for parameter estimation.We find that Gaussian models are remarkably robust to non-normality over a wide range of conditions, meaning that P-values remain fairly reliable except for data with influential outliers judged at strict alpha levels. Gaussian models also perform well in terms of power and they can be useful for parameter estimation but usually not for extrapolation. Transformation of data before analysis is often advisable and visual inspection for outliers and heteroscedasticity is important for assessment. In strong contrast, some non-Gaussian models and randomization techniques bear a range of risks that are often insufficiently known. High rates of false-positive conclusions can arise for instance when overdispersion in count data is not controlled appropriately or when randomization procedures ignore existing non-independencies in the data.Overall, we argue that violating the normality assumption bears risks that are limited and manageable, while several more sophisticated approaches are relatively error prone and difficult to check during peer review. Hence, as long as scientists and reviewers are not fully aware of the risks, science might benefit from preferentially trusting Gaussian mixed models in which random effects account for non-independencies in the data in a transparent way.Tweetable abstractGaussian models are remarkably robust to even dramatic violations of the normality assumption.