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Abstract Abundance-weighted averaging is a simple and common method for estimating taxon preferences (optima) for phosphorus (P) and other environmental drivers of freshwater-ecosystem health. These optima can then be used to develop transfer functions to infer current and/or past environmental conditions of aquatic ecosystems in water-quality assessments and/or paleolimnological studies. However, estimates of species’ environmental preferences are influenced by the sample distribution and length of environmental gradients, which can differ between datasets used to develop and apply a transfer function. Here, we introduce a subsampling method to ensure a uniform and comparable distribution of samples along a P gradient in two similar ecosystems: the Everglades Protection Areas (EPA) and Big Cypress National Preserve (BICY) in South Florida, USA. Diatom optima were estimated for both wetlands using weighted averaging of untransformed and log-transformed periphyton mat total phosphorus (mat TP) values from the original datasets. We compared these estimates to those derived from random subsets of the original datasets. These subsets, referred to as “SUD” datasets, were created to ensure a uniform distribution of mat TP values along the gradient (both untransformed and log-transformed). We found that diatom assemblages in BICY and EPA were similar, dominated by taxa indicating oligotrophic conditions, and strongly influenced by P gradients. However, the original BICY datasets contained more samples with elevated mat TP concentrations than the EPA datasets, introducing a mathematical bias and resulting in a higher abundance of taxa with high mat TP optima in BICY. The weighted averaged mat TP optima of BICY and EPA taxa were positively correlated across all four dataset types, with taxa optima of SUD datasets exhibiting higher correlations than in the original datasets. Equalizing the mat TP sample distribution in the two datasets confirmed consistent mat TP estimates for diatom taxa between the two wetland complexes and improved transfer-function performance. Our findings suggest that diatom environmental preferences may be more reliable across regional scales than previously suggested and support the application of models developed in one region to another nearby region if environmental gradient lengths are equalized and data distribution along gradients is uniform. 

{"Abstract":["Environmental and diatom data were collected from sites in the Big Cypress National Preserve (BICY) by the South Florida/Caribbean Inventory and Monitoring Network of the National Park Service and from sites in the Everglades Protection Area (EPA) as part of the Monitoring and Assessment Program of the Comprehensive Everglades Restoration Plan. Samples from years 2012, 2013, 2019, 2019, and 2020 are included in this dataset. Environmental data include drier variables that have been found to influence diatom assemblage composition in the greater Everglades ecosystem, including periphyton mat total phosphorus (a proxy for phosphorus in the environment), water column pH, water column conductivity, water depth, days since last dry, and hydroperiod. Diatom data include diatom species composition as percent relative abundances. Code included is pertinent to the methods described in "Robust species optima estimates from non-uniformly sampled environmental gradients" by Solomon et al. 2025, Journal of Paleolimnology."]} 

Coenzyme Q (CoQ) is a redox-active lipid molecule that acts as an electron carrier in the mitochondrial electron transport chain. In Saccharomyces cerevisiae, CoQ is synthesized in the mitochondrial matrix by a multi-subunit protein-lipid complex termed the CoQ synthome, the spatial positioning of which is coordinated by the Endoplasmic Reticulum-Mitochondria Encounter Structure (ERMES). The MDM12 gene encoding the cytosolic subunit of ERMES, is co-expressed with COQ-10, which encodes the putative CoQ chaperone Coq10, via a shared bidirectional promoter. Deletion of COQ10 results in respiratory deficiency, impaired CoQ biosynthesis, and reduced spatial coordination between ERMES and the CoQ Synthome. While Coq10 protein content is maintained upon deletion of MDM12, we show that deletion of COQ10 by replacement with a HIS3 marker results in diminished Mdm12 protein content. Since deletion of individual ERMES subunits prevents ERMES formation, we asked whether some or all of the phenotypes associated with COQ10 deletion result from ERMES dysfunction. To identify the phenotypes resulting solely due to the loss of Coq10, we constructed strains expressing a functionally impaired (coq10-L96S) or truncated (coq10-R147*) Coq10 isoform using CRISPR-Cas9. We show that both coq10 mutants preserve Mdm12 protein content and exhibit impaired respiratory capacity like the coq10Δ mutant, indicating that Coq10’s function is vital for respiration regardless of ERMES integrity. Moreover, the maintenance of CoQ synthome stability and efficient CoQ biosynthesis observed for the coq10-R147* mutant suggests these deleterious phenotypes in the coq10Δ mutant result from ERMES disruption. Overall, this study clarifies the role of Coq10 in modulating CoQ biosynthesis. 

ABSTRACT This study investigates a previously unreported stress signal transduced as crosstalk between the cell wall integrity (CWI) pathway and the septation initiation network (SIN). Echinocandins, which target cell wall synthesis, are widely used to treat mycoses. Their efficacy, however, is species specific. Our findings suggest that this is due largely to CWI–SIN crosstalk and the ability of filamentous species to fortify with septa in response to echinocandin stress. To better understand this crosstalk, we used a microscopy-based assay to measure septum density, aiming to understand the septation response to cell wall stress. The echinocandin micafungin, an inhibitor of β-(1,3)-glucan synthase, was employed to induce this stress. We observed a strong positive correlation between micafungin treatment and septum density in wild-type strains. This finding suggests that CWI activates SIN under cell wall stress, increasing septum density to protect against cell wall failure. More detailed investigations, with targeted knockouts of CWI and SIN signaling proteins, enabled us to identify crosstalk occurring between the CWI kinase, MpkA, and the SIN kinase, SepH. This discovery of the previously unknown crosstalk between the CWI and SIN pathways not only reshapes our understanding of fungal stress responses, but also unveils a promising new target pathway for the development of novel antifungal strategies. IMPORTANCEEchinocandin-resistant species pose a major challenge in clinical mycology by rendering one of only four lines of treatment, notably one of the two that are well-tolerated, ineffective in treating systemic mycoses of these species. Previous studies have demonstrated that echinocandins fail against highly polarized fungi because they target only apical septal compartments. It is known that many filamentous species respond to cell wall stress with hyperseptation. In this work, we show that echinocandin resistance hinges on this dynamic response, rather than on innate septation alone. We also describe, for the first time, the signaling pathway used to deploy the hyperseptation response. By disabling this pathway, we were able to render mycelia susceptible to echinocandin stress. This work enhances our microbiological understanding of filamentous fungi and introduces a potential target to overcome echinocandin-resistant species. 

In this essay, we review how counter-stereotypical scientists have been featured in life science courses and discuss the benefits and costs of developing and interacting with these materials from the perspectives of three groups: students, instructors, and the featured scientists. 

Behavior is often linked to gonadal sex; however, ecological or social environments can induce plasticity in sex-biased behaviors. In biparental species, pairs may divide offspring care into two parental roles, in which one parent specializes in territory defense and the other in nest care. The African cichlid fish Julidochromis marlieri displays plasticity in sex-biased behaviors. In Lake Tanganyika, J. marlieri form female-larger pairs in which the female is more aggressive than the male who performs more nest care, but under laboratory conditions, male-larger pairs can be formed in which these sex-biased behaviors are reversed. We investigated the influence of social environment on behavior by observing how individuals in both pair-types respond to conspecific intruders of either sex. We examined behavioral responses to three factors: sex of the subject, relative size of the subject, and the sex of the intruder. We confirm that relative size is a factor in behavior. The larger fish in the pair is more aggressive than the smaller fish is towards an intruder. While neither fish in the female-larger pairs varied their behaviors in response to the sex of the intruder, both members of the male-larger pairs were sensitive to intruder sex. Both individuals in the male-larger pairs engaged in more biting behaviors towards the intruder. Intruder biting behaviors strongly correlated with the biting behavior of the larger individual in the pair and occurred more frequently when encountering pairs with same sex as the larger fish when compared to pairs with the same sex as the smaller fish. Our results support the role of the social environment as a contributor in the expression of sex-biased behavior. 

Abstract We propose a new measurement of the ratio of positron-proton to electron-proton elastic scattering at DESY. The purpose is to determine the contributions beyond single-photon exchange, which are essential for the Quantum Electrodynamic (QED) description of the most fundamental process in hadronic physics. By utilizing a 20 cm long liquid hydrogen target in conjunction with the extracted beam from the DESY synchrotron, we can achieve an average luminosity of$$2.12\times 10^{35}$$ $2.12\times {10}^{35}$ cm$$^{-2}\cdot $$ ${}^{-2}·$s$$^{-1}$$ ${}^{-1}$ ($$\approx 200$$ $\approx 200$times the luminosity achieved by OLYMPUS). The proposed two-photon exchange experiment (TPEX) entails a commissioning run at a beam energy of 2 GeV, followed by measurements at 3 GeV, thereby providing new data up to$$Q^2=4.6$$ $Q^2=4.6$ (GeV/c)$$^2$$ ${}^2$(twice the range of current measurements). We present and discuss the proposed experimental setup, run plan, and expectations. 

Evidence from victim service providers suggests the COVID-19 pandemic led to an increase in family violence. However, empirical evidence has been limited. This study uses novel survey data to investigate the occurrence of family violence during the early months of the COVID-19 pandemic in the United States. Data come from the second wave of the Assessing the Social Consequences of COVID-19 study, an online non-probability sample collected in April and May 2020. Family violence is measured using four variables: any violence, physical violence, verbal abuse, and restricted access. The authors use logistic regression and KHB decomposition to examine the prevalence of family violence during the COVID-19 pandemic. We find that sexual minorities, in particular bisexual people, experienced higher rates of family violence than heterosexual respondents. Women were the only group to report an increase in the frequency of family violence. Household income loss is associated with the incidence of verbal violence. Our findings demonstrate the importance of expanding victim services to address the additional barriers victims face within the pandemic context and beyond, including broad contexts of social isolation and financial precarity experienced by individuals at risk of family violence. 

Lignin valorization is being intensely pursued via tandem catalytic depolymerization and biological funneling to produce single products. In many lignin depolymerization processes, aromatic dimers and oligomers linked by carbon–carbon bonds remain intact, necessitating the development of enzymes capable of cleaving these compounds to monomers. Recently, the catabolism oferythro-1,2-diguaiacylpropane-1,3-diol (erythro-DGPD), a ring-opened lignin-derived β-1 dimer, was reported inNovosphingobium aromaticivorans. The first enzyme in this pathway, LdpA (formerly LsdE), is a member of the nuclear transport factor 2 (NTF-2)-like structural superfamily that convertserythro-DGPD to lignostilbene through a heretofore unknown mechanism. In this study, we performed biochemical, structural, and mechanistic characterization of theN. aromaticivoransLdpA and another homolog identified inSphingobiumsp. SYK-6, for which activity was confirmed in vivo. For both enzymes, we first demonstrated that formaldehyde is the C₁reaction product, and we further demonstrated that both enantiomers oferythro-DGPD were transformed simultaneously, suggesting that LdpA, while diastereomerically specific, lacks enantioselectivity. We also show that LdpA is subject to a severe competitive product inhibition by lignostilbene. Three-dimensional structures of LdpA were determined using X-ray crystallography, including substrate-bound complexes, revealing several residues that were shown to be catalytically essential. We used density functional theory to validate a proposed mechanism that proceeds via dehydroxylation and formation of a quinone methide intermediate that serves as an electron sink for the ensuing deformylation. Overall, this study expands the range of chemistry catalyzed by the NTF-2-like protein family to a prevalent lignin dimer through a cofactorless deformylation reaction.