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Anisogramma anomala , a biotrophic ascomycete, causes eastern filbert blight (EFB) of hazelnuts ( Corylus spp.). EFB is endemic in eastern North America, preventing the commercial production of European hazelnut ( C. avellana L.). In contrast, the historic absence of A. anomala in the Pacific Northwest (PNW) supported the development of a robust hazelnut industry. Circa 1960, A. anomala was inadvertently introduced into southwestern Washington, causing orchard devastation. Distribution of the pathogen in the PNW has been hypothesized to be the result of a single-point introduction. This study aimed to investigate the single-point introduction hypothesis of A. anomala by comparing the genetic diversity of A. anomala samples from the PNW and New Jersey (NJ). Specimens from the main PNW production region ( n = 60) and an area within the pathogen's native range, NJ ( n = 151), were genotyped using 15 simple sequence repeat (SSR) markers. The following were used to assess genetic diversity and population structure: allelic summary statistics, discriminant analysis of principal components, network median-joining tree, analysis of multilocus genotypes, and allelic population diversity analysis. Analyses separated the samples into one cluster containing all the PNW isolates, and five clusters of NJ isolates. The PNW samples were nearly genetically uniform, and the NJ isolates were diverse. These findings support the hypothesis that A. anomala in the PNW was derived from a single-point introduction and corroborate previous studies that have shown A. anomala is very diverse in NJ. This indicates that maintaining restrictions on the movement of Corylus into the PNW is important to prevent the introduction of new populations of A. anomala , thus protecting the PNW hazelnut industry., Competing Interests: The author(s) declare no conflict of interest.

Big-bracted dogwoods are popular ornamental trees known for their beautiful spring blooms with showy bracts and four-season appeal. The two most widely grown species are Cornus florida and Cornus kousa, native to Eastern North America and East Asia. Despite their horticultural prominence, there is little information available regarding genetic diversity, population structure, relatedness, and subspecies origins of dogwood cultivars. In this study, 313 cultivars, wild-collected plants, and Rutgers University breeding selections, focusing on C. florida, C. kousa, and interspecific hybrids, were genotyped using restriction-site associated DNA sequencing (RADseq) generating thousands of single nucleotide polymorphism (SNP) and insertion deletion (Indel) markers. The research results showed high genetic diversity among C. florida and C. kousa wild-collected plants and cultivars. For C. florida, pink-bracted plants formed a distinct clade from those with white-bracts with the Mexican C. florida ssp. urbiniana forming an outgroup. For C. kousa, Chinese-collected plants (ssp. chinensis) were a distinct subspecies with clear separation from Japanese and Korean accessions (ssp. kousa) and cultivars were designated as ssp. chinensis, ssp. kousa, or ssp. hybrid. Using this information, a Kompetitive allele specific PCR (KASP) assay genotyping panel was designed to determine C. kousa trees' subspecies makeup. Results revealed many cases of genetically identical cultivars being sold under different names, especially for pink-bracted cultivars of both species. Additionally, reported parent-progeny relationships were evaluated and either validated or discredited. Finally, the hybrid germplasm analysis validated pedigrees of interspecific F1 hybrids and found many of the recent Rutgers breeding selections contain small regions of pacific dogwood (C. nuttallii) DNA introgressed into C. kousa backgrounds. This diversity study elucidates origins, diversity, and relationships of a large population of big-bracted dogwoods. The results can inform plant breeders, arboreta, and the ornamental plant industry, as most modern cultivars and popular historic cultivars are represented., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

Background Initial Glasgow Coma Score (iGCS) is a well-known predictor of adverse outcomes following chronic subdural hemorrhage (cSDH). Frailty, i.e. a reduced physiologic reserve, is associated with poorer outcomes across the surgical literature, however, there is no consensus on the best measure of frailty. To date, no study has compared frailty's ability to predict cSDH outcomes versus iGCS. The goal of this study was to, therefore, examine the prognostic value of the 5- (mFI-5) and 11-factor (mFI-11) modified frailty index, and Charlson Comorbidity Index (CCI) versus iGCS following cSDH. Methods Between January, 2016 and June, 2018, patients who presented to the emergency department with cSDH were retrospectively identified using the International Classification of Diseases (ICD) codes. mFI-5, mFI-11, and CCI scores were calculated using patient baseline characteristics. Primary endpoints were death and discharge home and subgroup analyses were performed among operative cSDH. Univariate and multivariate logistic regressions were used to determine predictors of primary endpoints. Results Of the 109 patients identified, the average age was 72.6±1.6 years and the majority (69/109, 63.3%) were male. The average CCI, mFI-5, and mFI-11 were 4.5 ±0.2, 1.5 ±0.1, and 2.2 ±0.1, respectively. Fifty (45.9%) patients required surgical intervention, 11 (10.1%) died, and 48 (43.4%) were discharged home. In the overall cohort, while the only multivariate predictor of mortality was iGCS (OR=0.58; 95%CI:0.44-0.77; p=0.0001), the CCI (OR=0.73; 95%CI:0.58-0.92; p=0.0082) was a superior predictor of discharge home compared to iGCS (OR=1.46; 95%CI:1.13-1.90; p=0.0041). Conversely, among those who received an operative intervention, the CCI, but not iGCS, independently predicted both mortality (OR=4.24; 95%CI:1.01-17.86; p=0.0491) and discharge home (OR=0.55; 95%CI:0.33-0.90; p=0.0170). Neither mFI nor age predicted primary outcomes in multivariate analysis. Conclusion While frailty is associated with worse surgical outcomes, the clinical utility of the mFI-5, mFI-11, and CCI in cSDH is unclear. We show that the iGCS is an overall superior predictor of mortality following cSDH but is outperformed by the CCI after operative intervention. Similarly, the CCI is the superior predictor of discharge home in cSDH patients overall and following an operative intervention. These results indicate that while the iGCS best predicts mortality overall, the CCI may be considered when prognosticating post-operative course and hospital disposition., Competing Interests: This work was supported, in part, by a grant from New York Medical College for medical student research., (Copyright © 2020, McIntyre et al.)

Anisogramma anomala , a biotrophic ascomycete in the order Diaporthales, causes eastern filbert blight (EFB) of hazelnuts ( Corylus spp.). Until recently, little has been documented on its genetic diversity and population structure. In this study, 18 simple sequence repeat markers were used to fingerprint 182 accessions of the fungus originating from across North America. Our results, based on summary statistics of the allelic data, a discriminant analysis of principal components (DAPC) scatterplot, an unweighted pair group method with arithmetic mean (UPGMA) dendrogram, and analysis of multilocus genotypes, show that A. anomala exhibits considerable genetic diversity across multiple populations. Eleven clusters were resolved from the DAPC scatterplot, five of which were validated by statistically supported clusters in the UPGMA dendrogram. The 11 DAPC clusters were statistically significant via an analysis of molecular variance. Dendrogram topology and DAPC scatterplot groups showed some correlation with collection origin; samples collected in proximity tended to cluster together and be genetically similar. However, some locations held populations that were diverse and some populations with a high degree of similarity had disparate origins, suggesting movement by humans. Overall, the results demonstrate the presence of multiple, genetically distinct populations of A. anomala in North America and serve as a reference to assist in understanding and managing EFB.

Background: The basil (Ocimum spp.) genus maintains a rich diversity of phenotypes and aromatic volatiles through natural and artificial outcrossing. Characterization of population structure and genetic diversity among a representative sample of this genus is severely lacking. Absence of such information has slowed breeding efforts and the development of sweet basil (Ocimum basilicum L.) with resistance to the worldwide downy mildew epidemic, caused by the obligate oomycete Peronospora belbahrii. In an effort to improve classification of relationships 20 EST-SSR markers with species-level transferability were developed and used to resolve relationships among a diverse panel of 180 Ocimum spp. accessions with varying response to downy mildew., Results: Results obtained from nested Bayesian model-based clustering, analysis of molecular variance and unweighted pair group method using arithmetic average (UPGMA) analyses were synergized to provide an updated phylogeny of the Ocimum genus. Three (major) and seven (sub) population (cluster) models were identified and well-supported (P < 0.001) by PhiPT (Φ PT ) values of 0.433 and 0.344, respectively. Allelic frequency among clusters supported previously developed hypotheses of allopolyploid genome structure. Evidence of cryptic population structure was demonstrated for the k1 O. basilicum cluster suggesting prevalence of gene flow. UPGMA analysis provided best resolution for the 36-accession, DM resistant k3 cluster with consistently strong bootstrap support. Although the k3 cluster is a rich source of DM resistance introgression of resistance into the commercially important k1 accessions is impeded by reproductive barriers as demonstrated by multiple sterile F1 hybrids. The k2 cluster located between k1 and k3, represents a source of transferrable tolerance evidenced by fertile backcross progeny. The 90-accession k1 cluster was largely susceptible to downy mildew with accession 'MRI' representing the only source of DM resistance., Conclusions: High levels of genetic diversity support the observed phenotypic diversity among Ocimum spp. accessions. EST-SSRs provided a robust evaluation of molecular diversity and can be used for additional studies to increase resolution of genetic relationships in the Ocimum genus. Elucidation of population structure and genetic relationships among Ocimum spp. germplasm provide the foundation for improved DM resistance breeding strategies and more rapid response to future disease outbreaks.

Age-related decline in fluid cognition can be characterized as a disconnection among specific brain structures, leading to a decline in functional efficiency. The potential sources of disconnection, however, are unclear. We investigated imaging measures of cerebral white-matter integrity, resting-state functional connectivity, and white-matter hyperintensity volume as mediators of the relation between age and fluid cognition, in 145 healthy, community-dwelling adults 19-79 years of age. At a general level of analysis, with a single composite measure of fluid cognition and single measures of each of the 3 imaging modalities, age exhibited an independent influence on the cognitive and imaging measures, and the imaging variables did not mediate the age-cognition relation. At a more specific level of analysis, resting-state functional connectivity of sensorimotor networks was a significant mediator of the age-related decline in executive function. These findings suggest that different levels of analysis lead to different models of neurocognitive disconnection, and that resting-state functional connectivity, in particular, may contribute to age-related decline in executive function., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Premise of the Study: Microsatellite markers were developed for the invasive plant Microstegium vimineum (Poaceae) to assess its population structure and to facilitate tracking of invasion expansion., Methods and Results: Using 454 sequencing, 11 polymorphic and six monomorphic microsatellite primer sets were developed for M. vimineum. The primer sets were tested on individuals sampled from six populations in the United States and China. The polymorphic primers amplified di-, tri-, and tetranucleotide repeats with three to 10 alleles per locus., Conclusions: These markers will be useful for a variety of applications including tracking of invasion dynamics and population genetics studies.