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We conducted a post-project appraisal in November 2022 to evaluate the restoration’s performance using the goals outlined in the Sausal Creek Restoration at Dimond Park Monitoring Plan (Restoration Design Group, Inc. (RDG) 2017): restore native riparian habitat and improve channel stability. We performed vegetation surveys along the three transects (T1, T2, T3) initially defined by RDG and conducted a geomorphic survey along T3. We determined that the restoration project performed well in establishing native riparian habitat as we measured overall >90% canopy cover, which surpasses the percent cover criteria of 75% after five years of project implementation. Furthermore, we observed relatively high shrub survival rates of 138%at T1 and 173% at T2 and a limited shrub survival rate of 35% at T3. Despite meeting overall percent cover and survival rate criteria, we observed a decrease in native flora diversity, potentially due to excessive overstory shading from willows and invasive species outcompeting native plant species. Therefore, we recommend strategic thinning of willows, continued removal of invasive species, and additional replanting of native species. We compared the November 2022 channel geometry to previous years (pre-project, design, 2017, 2019, and 2021) and determined that the channel banks are stable (i.e., have experienced less than one foot of erosion). We also modeled the new channel geometry’s ability to convey a 10-year and 50-year storm event. Our model (HEC-RAS and the National Weather Service Normal Depth Calculator) results indicated that the channel would contain a 10-year event but not a 50-year event.

Observational studies suggest that nutritional factors have a potential cognitive benefit. However, systematic reviews of randomised trials of dietary and nutritional supplements have reported largely null effects on cognitive outcomes and have highlighted study inconsistencies and other limitations. In this Personal View, the Nutrition for Dementia Prevention Working Group presents what we consider to be limitations in the existing nutrition clinical trials for dementia prevention. On the basis of this evidence, we propose recommendations for incorporating dietary patterns and the use of genetic, and nutrition assessment tools, biomarkers, and novel clinical trial designs to guide future trial developments. Nutrition-based research has unique challenges that could require testing both more personalised interventions in targeted risk subgroups, identified by nutritional and other biomarkers, and large-scale and pragmatic study designs for more generalisable public health interventions across diverse populations.

Fungus-growing ants engage in a multilateral symbiosis: they cultivate a fungal garden as their primary food source and host symbiotic actinobacteria (Pseudonocardia spp.) that provide chemical defenses. The bacterial symbionts produce small specialized metabolites that protect the fungal garden from specific fungal pathogens (Escovopsis spp.), and in return, they are fed by the ant hosts. Multiple studies on the molecules underlying this symbiotic system have led to the discovery of a large number of structurally diverse antifungal molecules, but somewhat surprisingly no shared structural theme emerged from these studies. A large systematic study of Brazilian nests led to the discovery of the widespread production of a potent but overlooked antifungal agent, which we named attinimicin, by nearly two-thirds of all Pseudonocardia strains from multiple sites in Brazil. Here we report the structure of attinimicin, its putative biosynthetic gene cluster, and the evolutionary relationship between attinimicin and two related peptides, oxachelin A and cahuitamycin A. All three nonribosomal peptides are structural isomers with different primary peptide sequences. Attinimicin shows iron-dependent antifungal activity against specific environmental fungal parasites but no activity against the fungal cultivar. Attinimicin showed potent in vivo activity in a mouse Candida albicans infection model comparable to clinically used azole-containing antifungals. In situ detection of attinimicin in both ant nests and on worker ants supports an ecological role for attinimicin in protecting the fungal cultivar from pathogens. The geographic spread of the attinimicin biosynthetic gene cluster in Brazilian Pseudonocardia spp. marks attinimicin as the first specialized metabolite from ant-associated bacteria with broad geographic distribution.

Fungus-growing ants engage in a multilateral symbiosis: they cultivate a fungal garden as their primary food source and host symbiotic actinobacteria (Pseudonocardia spp.) that provide chemical defenses. The bacterial symbionts produce small specialized metabolites that protect the fungal garden from specific fungal pathogens (Escovopsis spp.), and in return, they are fed by the ant hosts. Multiple studies on the molecules underlying this symbiotic system have led to the discovery of a large number of structurally diverse antifungal molecules, but somewhat surprisingly no shared structural theme emerged from these studies. A large systematic study of Brazilian nests led to the discovery of the widespread production of a potent but overlooked antifungal agent, which we named attinimicin, by nearly two-thirds of all Pseudonocardia strains from multiple sites in Brazil. Here we report the structure of attinimicin, its putative biosynthetic gene cluster, and the evolutionary relationship between attinimicin and two related peptides, oxachelin A and cahuitamycin A. All three nonribosomal peptides are structural isomers with different primary peptide sequences. Attinimicin shows iron-dependent antifungal activity against specific environmental fungal parasites but no activity against the fungal cultivar. Attinimicin showed potent in vivo activity in a mouse Candida albicans infection model comparable to clinically used azole-containing antifungals. In situ detection of attinimicin in both ant nests and on worker ants supports an ecological role for attinimicin in protecting the fungal cultivar from pathogens. The geographic spread of the attinimicin biosynthetic gene cluster in Brazilian Pseudonocardia spp. marks attinimicin as the first specialized metabolite from ant-associated bacteria with broad geographic distribution.

Recognition of the AVRPM3A2/F2 avirulence protein from powdery mildew by the wheat PM3A/F immune receptor induces a hypersensitive response after co‐expression in Nicotiana benthamiana. The molecular determinants of this interaction and how they shape natural AvrPm3a2/f2 allelic diversity are unknown. We sequenced the AvrPm3a2/f2 gene in a worldwide collection of 272 mildew isolates. Using the natural polymorphisms of AvrPm3a2/f2 as well as sequence information from related gene family members, we tested 85 single‐residue‐altered AVRPM3A2/F2 variants with PM3A, PM3F and PM3FL456P/Y458H (modified for improved signaling) in Nicotiana benthamiana for effects on recognition. An intact AvrPm3a2/f2 gene was found in all analyzed isolates and the protein variant recognized by PM3A/F occurred globally at high frequencies. Single‐residue alterations in AVRPM3A2/F2 mostly disrupted, but occasionally enhanced, the recognition response by PM3A, PM3F and PM3FL456P/Y458H. Residues enhancing hypersensitive responses constituted a protein domain separate from both naturally occurring polymorphisms and positively selected residues of the gene family. These results demonstrate the utility of using gene family sequence diversity to screen residues for their role in recognition. This approach identified a putative interaction surface in AVRPM3A2/F2 not polymorphic in natural alleles. We conclude that molecular mechanisms besides recognition drive AvrPm3a2/f2 diversification.