For a positive integer k and a graph H on k vertices, we are interested in the inducibility of H, denoted ind(H), which is defined as the maximum possible probability that k vertices chosen uniformly at random from a large graph G induce a copy of H. It follows from the resolved Edge-statistics conjecture that if H∉{Kk,Kk‾}, then ind(H)≤1/e+ok(1). Equality holds for the star graph K1,k−1, the graph with a single edge on k vertices and their complements. We prove that for all other graphs H, we have ind(H)≤c+ok(1) for an absolute constant c<1/e. Moreover, we explicitly characterize all graphs with inducibility bounded away from zero. Namely, we show that this is the class of graphs H for which there is a set V0⊆V(H) of bounded size with the property that all permutations of V(H)﹨V0 extend to an automorphism of H.
The successful deployment of entomopathogenic nematodes (EPN) in biological pest control hinges on their ecological fitness and stress tolerance. In this study, we assessed the ecological traits and efficacy of six indigenous EPN isolates previously identified from distinct agroecological zones in Nigeria, targeting the invasive pest Spodoptera frugiperda (fall armyworm, FAW). The isolates, identified as Heterorhabditis bacteriophora (Ib-CRIN68), Steinernema carpocapsae (Ib-IART45, Ib-ITUC102), Steinernema feltiae (Za-SAM), Steinernema nepalense (Ib-HORT), and Oscheius myriophilus (Ib-FRIN32), were subjected to a series of ecological bioassays to evaluate their performance under temperature variation, moisture stress, oxygen limitation, oxidative stress, and foraging conditions. Results revealed significant inter-and intra-isolate variability in ecological tolerance traits. Optimal infectivity and reproduction were recorded between 25 and 30 degrees C, while mortality sharply declined at 10 degrees C and 35 degrees C. Foraging ability varied across substrates and soil depths, with S. carpocapsae isolates exhibiting strong host-finding capability under dry and surface conditions. Desiccation and oxidative stress assays also demonstrated the superior resilience of S. carpocapsae isolates, which sustained low mortality under polyethylene glycol induced water stress and H2O2 exposure. Hypoxia assays indicated that all isolates were moderately tolerant to short-term anoxia, but only H. bacteriophora and the S. carpocapsae isolates survived above 50% at 72 h. Our study highlights the relevance of ecological screening as a prerequisite for selecting robust EPN candidate species and isolates suitable for biological control under variable conditions. The findings support the integration of indigenous EPN into sustainable pest management frameworks in sub-Saharan Africa.
Germany lacks a standardised and coordinated farmland biodiversity monitoring framework. However, several independent and heterogeneous programmes generate datasets for farmland-related biodiversity assessments. These programmes have limitations, including limited taxonomic coverage, lack of long-term trends, and insufficient data on agricultural land use/management, affecting the early detection of declining ecosystem conditions. MonViA, launched in 2019, is a nationwide, representative, and science-based framework that addresses key gaps in farmland biodiversity monitoring, aiming to develop monitoring concepts and indicators for agri-environmental policy for Germany. MonViA complements existing monitoring programmes with its farmland focus, national-level indicators on habitat, species, and genetic diversity, and modular design. The chapter outlines key steps towards an integrated farmland biodiversity monitoring in Germany through improved survey designs, novel survey methods, and advancements in data management, access, and integration. Strengthening farmland biodiversity monitoring and integrating it into policy and practice is urgently needed for supporting effective conservation and land-management decisions.
Objectives To evaluate the effects of restorative substrate, pre-repair substrate aging, airborne-particle abrasion, adhesive application, and post-repair aging on the shear bond strength (SBS) of repairs performed with a self-adhesive composite hybrid. Methods The substrates were a conventional glass-ionomer cement (ChemFil Rock), a nanohybrid resin composite (Ceram.x Spectra ST), and a composite hybrid (Surefil one), which also served as the repair material in all groups. A 3 × 2 × 2 × 2 × 2 factorial design comprised 48 groups (n = 9; total n = 432). Substrates were thermocycled or unaged, standardized by P320 grinding, and optionally subjected to airborne-particle abrasion with 50-μm Al2O3 and/or adhesive application. Completed repairs were thermocycled or left unaged. SBS was analyzed using a categorical fixed-effects model with HC3-robust inference and planned Welch comparisons with Holm adjustment. Pre-test failures (PTFs) were included as 0 MPa. Results Sixty-eight PTFs occurred (15.7%): 51 with the glass-ionomer cement, 17 with the composite hybrid, and none with the conventional composite. Significant main effects were found for all five experimental factors (p < 0.001). Under dual aging, the complete pretreatment protocol yielded the highest mean SBS for every substrate: 2.75 MPa for the glass-ionomer cement, 11.65 MPa for the conventional composite, and 12.60 MPa for the composite hybrid. Significance Surefil one showed potential for repairing the tested aged resin-containing substrates when the tested external adhesive was applied, whereas bonding to ChemFil Rock remained weak after aging. The substrate-dependent response highlights the importance of material composition in repair-protocol selection.
This manuscript describes the establishment of a local production line for 10 cm & times; 10 cm Gas Electron Multiplier (GEM) foils at the Forschungs-und Technologiezentrum Detektorphysik (FTD) at the University of Bonn. GEM foils are widely used in modern gaseous detectors, providing high-gain signal amplification and high-rate capability. Our fabrication process utilizes a double-mask photolithographic technique on 50 & micro;m polyimide cladded on both sides with 5 & micro;m copper. The chemical etching procedure that is required to achieve uniform hole geometries with outer hole diameters of 70 & micro;m and inner hole diameters of 50 & micro;m will be described. Quality control protocols, including semi-automated optical inspection and high-voltage leakage current tests, demonstrate that foils produced at our facility achieve uniform hole size distributions and leakage currents of less than 1 nA at 600 V in air with no discharge hotspots. These results confirm that the production chain is capable of delivering high-performance foils suitable for research and development purposes.
