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Abstract The need for widespread occurrence data to inform species conservation has prompted interest in large, national‐scale environmental DNA (eDNA) monitoring strategies. However, targeted eDNA assays are seldom validated for use across broad geographic areas. Here, we validated 46 new and previously published probe‐based qPCR assays targeting invasive species throughout the continental United States. We drew upon current taxonomies, range maps, publicly available sequences, and tissue archives to evaluate all potentially sympatric confamilial species and genetically similar extrafamilial taxa. Out of 5276 unique assay‐nontarget taxon combinations, we were able to test 4206 (80%). We characterized levels of validation and specificity for each of eight federal geographic regions and provided an online tool with state‐level information, as well as detailed assay descriptions in an appendix. Specificity testing benefited from extensive use of eDNAssay—a machine learning classifier trained to predict qPCR cross‐amplification—which we found to be 96% accurate in 649 unique tests that underwent paired in silico and in vitro testing. Predictions of assay specificity (the true negative rate) were 98–100% accurate, depending on the classification threshold used. This work provides both an immediate resource for invasive species surveillance and demonstrates an enhanced in silico, geographically subdivided validation framework to aid in future large‐scale validation efforts.

Abstract Relating environmental DNA (eDNA) signal strength to organism abundance requires a fundamental understanding of eDNA production. A number of studies have demonstrated that eDNA production may scale allometrically—that is, larger organisms tend to exhibit lower mass‐specific eDNA production rates, likely due to allometric scaling in key processes related to eDNA production (e.g., surface area, excretion/egestion). While most previous studies have examined intraspecific allometry, physiological rates and organism surface area also scale allometrically across species. We therefore hypothesize that eDNA production will similarly exhibit interspecific allometric scaling. To evaluate this hypothesis, we reanalyzed previously published eDNA data from Stoeckle et al. (ICES Journal of Marine Science, 78(1), 293–304, 2021) which compared metabarcoding read count to organism count and biomass data obtained from trawl surveys off the New Jersey coast. Using a Bayesian model, we empirically estimated the value of the allometric scaling coefficient (“b”) for Northwestern Atlantic bony fishes to be 0.77 (credible interval = 0.64–0.92), although our model failed to converge for Chondrichthyan species. We found that integrating allometry significantly improved correlations between organism abundance and metabarcoding read count relative to traditional metrics of abundance (density and biomass) for bony fishes. Although substantial unexplained variation remains in the relationship between read count and organism abundance, our study provides evidence that eDNA production may scale allometrically across species in some contexts. Future studies investigating the relationship between eDNA signal strength and metrics of fish abundance could potentially be improved by accounting for allometry; to this end, we developed an online tool that can facilitate the integration of allometry in eDNA/abundance relationships.

Abstract Environmental DNA (eDNA) sampling is a powerful tool for rapidly characterizing biodiversity patterns for specious, cryptic taxa with incomplete taxonomies. One such group that are also of high conservation concern are North American freshwater gastropods. In particular, springsnails of the genus Pyrgulopsis (Family: Hydrobiidae) are prevalent throughout the western United States where >140 species have been described. Many of the described species are narrow endemics known from a single spring or locality, and it is believed that there are likely many additional species which have yet to be described. The distribution of these species across the landscape is of interest because habitat loss and degradation, climate change, groundwater mining, and pollution have resulted in springsnail imperilment rates as high as 92%. Determining distributions with conventional sampling methods is limited by the fact that these snails are often

Abstract Nutria (Myocastor coypus) is a semiaquatic rodent species that is invasive across multiple regions within the United States. Here, we evaluated a qPCR assay previously described for use in Japan for application across invasive populations in the United States. We also compared two environmental DNA sampling methodologies for this assay: field filtration of large volumes of water passed through filters versus direct sampling of small volumes of water. We validated assay specificity, generality, and sensitivity, compared assay performance between two independent laboratories, and successfully tested the assay in situ on a known wild population. The filtration method required fewer samples for environmental DNA detection than direct sampling, but the choice of methods should be assessed based on specific field conditions and time and budget considerations. Our extensive assay validation and comparison across laboratories suggest that the assay is ready to be applied in environmental DNA monitoring of nutria throughout the United States.

Abstract To generalize findings on the mechanisms and prognosis in Alzheimer's disease and related dementias (ADRD), it is critical for ADRD research to be representative of the population. Sociodemographic and health characteristics across ethnoracial groups included in the National Alzheimer's Coordinating Center sample (NACC) were compared to the nationally representative Health and Retirement Study (HRS). Baseline NACC data (n = 36,639) and the weighted 2010 HRS wave (N = 52,071,840) were included. We assessed covariate balance by calculating standardized mean differences across harmonized covariates (i.e., sociodemographic, health). NACC participants were older, more educated, with worse subjective memory and hearing, but endorsed fewer depressive symptoms compared to HRS participants. While all racial and ethnic groups in NACC differed from HRS participants in the same way overall, these differences were further amplified between racial and ethnic groups. NACC participants do not represent the U.S. population in key demographic and health factors, which differed by race and ethnicity. HIGHLIGHTS We examined selection factors included in NACC studies compared to a nationally representative sample. Selection factors included demographic and health factors and self‐reported memory concerns. Results suggest that NACC participants are not representative of the U.S. population. Importantly, selection factors differed across racial and ethnic groups. Findings are suggestive of selection bias within NACC studies.

Abstract Environmental DNA (eDNA) concentration exhibits a positive correlation with organism abundance in nature, but modeling this relationship could be substantially improved by incorporating the biology of eDNA production. A recent model (Molecular Ecology, 10.1111/mec.15543) extended models of physiological allometric scaling to eDNA production, hypothesizing that brook trout eDNA production scales nonlinearly with mass as a power function with scaling coefficients

Abstract Ecological restoration often requires translocating plant material from distant sites. Importing suitable plant material is important for successful establishment and persistence. Yet, published guidelines for seed transfer are available for very few species. Accurately predicting how transferred plants will perform requires multiyear and multi‐environment field trials and comprehensive follow‐up work, and is therefore infeasible given the number of species used in restoration programs. Alternative methods to predict the outcomes of seed transfer are valuable for species without published guidelines. In this study, we analyzed the genetic structure of an important shrub used in ecological restoration in the Southern Rocky Mountains called alder‐leaf mountain mahogany (Cercocarpus montanus). We sequenced DNA from 1,440 plants in 48 populations across a broad geographic range. We found that genetic heterogeneity among populations reflected the complex climate and topography across which the species is distributed. We identified temperature and precipitation variables that were useful predictors of genetic differentiation and can be used to generate seed transfer recommendations. These results will be valuable for defining management and restoration practices for mountain mahogany.

Abstract When analyzing environmental samples for DNA from multiple taxa, researchers must usually decide between iterative analyses with single‐taxon assays—which are reliable and sensitive, but also laborious to apply—and approaches such as metabarcoding that can simultaneously target multiple species, but which are less sensitive for detection across taxa. Here, we test an intermediate approach that allows efficient, parallel assessment of taxon‐specific qPCR assays via high‐throughput quantitative PCR (HT‐qPCR). Based on an assessment of over 500 environmental samples, we found that sensitivity and specificity of our HT‐qPCR approach were similar (concordance 0.900–1.000) to values achieved through single‐species qPCR in six out of seven assays tested. Thus, HT‐qPCR may provide analyses of similar quality as single‐species qPCR analyses for environmental DNA, but at a lower cost per taxon. We see this approach as being a valuable addition to the eDNA sampling toolbox, particularly for situations where reliable inferences are needed for a defined suite of rare invasive or imperiled taxa.

Abstract Introduction The extracellular matrix (ECM) provides structural support for neuronal, glial, and vascular components of the brain, and regulates intercellular signaling required for cellular morphogenesis, differentiation and homeostasis. We hypothesize that the pathophysiology of diffuse brain injury impacts the ECM in a multi‐dimensional way across brain regions and over time, which could facilitate damage and repair processes. Methods Experimental diffuse TBI was induced in male Sprague‐Dawley rats (325–375 g) by midline fluid percussion injury (FPI); uninjured sham rats serve as controls. Tissue from the cortex, thalamus, and hippocampus was collected at 15 min, 1, 2, 6, and 18 hr postinjury as well as 1, 3, 7, and 14 days postinjury. All samples were quantified by Western blot for glycoproteins: fibronectin, laminin, reelin, and tenascin‐C. Band intensities were normalized to sham and relative to β‐actin. Results In the cortex, fibronectin decreased significantly at 15 min, 1 hr, and 2 hr postinjury, while tenascin‐C decreased significantly at 7 and 14 days postinjury. In the thalamus, reelin decreased significantly at 2 hr, 3 and 14 days postinjury. In the hippocampus, tenascin‐C increased significantly at 15 min and 7 days postinjury. Conclusion Acute changes in the levels of these glycoproteins suggest involvement in circuit dismantling, whereas postacute levels may indicate a restorative or regenerative response associated with recovery from TBI.

Abstract Transferring plant material during ecological restoration has inherent risk. The use of seed transfer guidelines minimizes the possibility of introducing maladapted genotypes. We delineated biogeographic regions relevant to the distribution of Cercocarpus montanus for the purpose of creating provisional seed transfer zones for ecological restoration. We also modeled seed transfer guidelines using quantitative estimates of environmental tolerance and thresholds. Analyses identified broadscale environmental patterns relevant for seed transfer success. First, a species distribution model was used to identify the distribution of C. montanus. Next, we used non‐metric multidimensional scaling to investigate the structure of environmental data, and hierarchical cluster analysis to delineate biogeographic regions (i.e., environmental discontinuities) using species distribution data. Finally, we calculated measures of environmental tolerance and thresholds for C. montanus to model the probability of seed transfer success with multiple logistic regression. Biogeographic regionalization of C. montanus resulted in four major clusters, which agreed with ordination methods. Logistic regression was implemented using estimates of environmental tolerance and threshold data to model seed transfer success. We compared our species‐specific seed transfer zones and guidelines with other provisional seed transfer zone methods and found that our species‐specific methods performed better at explaining phenotypic variation of C. montanus in four out of six cases. Seed transfer zones are useful for restoration planning; however, zonal models fail to reflect much of the environmental heterogeneity present across the range of C. montanus. Continuous models for seed transfer success using environmental tolerance and thresholds enhance the development and use of seed transfer guidelines because they reflect landscape heterogeneity at a fine scale, and the results are relative to restoration sites of interest. Herein, we describe a methodology to construct provisional seed transfer zones and continuous seed transfer guidelines using species‐specific distribution models and multivariate analyses.

Abstract Background Reported incidence of blood transfusion reactions (TR) varies greatly. Objective To prospectively evaluate the incidence of acute TRs in dogs receiving allogenic blood products, using consensus definitions, and to assess factors associated with TRs. Animals Dogs (n = 858) administered allogenic blood products (n = 1542) between March and November 2022. Methods Prospective, multicenter surveillance study occurring in referral hospitals in the United States, United Kingdom, and Australia recording TRs in dogs administered blood products as defined by the consensus guidelines published by The Association of Veterinary Hematology and Transfusion Medicine in 2021. Results The incidence of acute TR was 8.9% (95% CI 7.0‐11.1) for packed red blood cells (pRBCs) and 4.5% (95% CI 2.9‐6.6) for plasma products. The most frequently reported TRs were febrile nonhemolytic TRs (FNHTR; 4%, 95% CI 2.8‐5.5) when administering pRBCs and allergic TRs (3.2%, 95% CI 1.80‐5.10) when administering plasma products. A higher dose of pRBC (adjusted odds ratio [aOR] 1.04 [95% CI 1.00‐1.08]) was associated with a higher odds of TR. Administration of pRBCs stored for longer than 28 days was associated with higher odds of FNHTR (aOR 4.10 [95% CI 1.58‐10.65]) and acute hemolytic TR (AHTR; OR 15.2 [95% CI 3.35‐68.70]) when compared with pRBCs stored for 14 days or fewer. Leukoreduction of pRBC was not associated with lower odds of developing a TR (OR 1.47 [95% CI 0.89‐2.42]). Conclusions and Clinical Importance Clinicians should be mindful of the age and dose of pRBC prescribed to dogs.