An updated list of the Mexican herpetofauna: with a summary of historical and contemporary studies.

The growth in our knowledge of the diversity of the herpetofauna of Mexico has occurred over the period of approximately 445 years from the work of Francisco Hernández to that of a broad multinational array of present-day herpetologists. The work of this huge group of people has established Mexico as one of the most significant centers of herpetofaunal biodiversity in the world. This status is the result of a complex orography, in addition to diverse habitats and environments and the biogeographic history of Mexico. The current herpetofauna consists of 1,421 native and introduced species, allocated to 220 genera, and 61 families. This figure is comprised of 1,405 native species and 16 non-native species (as of April 2023). The non-native species include two anurans, 13 squamates, and one turtle. The level of endemism is very high, presently lying at 63%, with this level expected to increase with time. Species richness varies among the 32 federal entities in the country, from a low of 50 in Tlaxcala to a high of 492 in Oaxaca. Amphibian species richness by state-level can be envisioned as comprising three levels of low, medium, and high, with the lowest levels occurring in the Peninsula of Baja California, a group of seven states in north-central and central Mexico, and a group of three states in the Yucatan Peninsula, with the highest levels occupying the southern states of Guerrero, Puebla, Veracruz, Oaxaca, and Chiapas, and the medium level in the remaining states of the country. Reptile species richness also can be allocated to three categories, with the lowest level occupying Baja California Sur, a group of central states, and the states of the Yucatan Peninsula, and the highest level found in a cluster of the states of Veracruz, Guerrero, Oaxaca, and Chiapas. Knowledge of the Mexican herpetofauna will continue to grow with additional studies on systematics, conservation, and the construction of checklists at various levels.

Perceptions Among Backcountry Skiers During the COVID-19 Pandemic: Avalanche Safety and Backcountry Habits of New and Established Skiers.

INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic impacted the ski industry worldwide by closing or limiting access to ski resorts. Subsequently, anecdotal reports of increased backcountry use emerged in the press, with concerns of inexperienced skiers causing or having problems in the backcountry. This study attempted to quantify this and identify motivations for new backcountry skiers. METHODS: Self-identified backcountry skiers and snowboarders (aged ≥18 y) in the United States and Canada completed an anonymous 29-question online survey distributed by regional avalanche centers, education providers, and skiing organizations (n=4792). Respondents were stratified by backcountry experience, defining "newcomers" who began backcountry skiing from 2019 to 2021, coincident with the COVID-19 pandemic. Percentages of ski days spent in the backcountry were compared before and during the COVID-19 pandemic using paired t-tests and across cohorts using repeated-measures analysis of variance. Avalanche education was compared using unpaired χ2 tests. RESULTS: Of established skiers, 81% noticed more people in the backcountry and 27% reported increasing their own use. Participants reported spending 17% (95% CI, 15.8-17.9) more of their days in the backcountry during the COVID-19 pandemic, with newcomers increasing their time spent by 36% and established skiers increasing their time spent by 13% (P<0.0001). Of newcomers, 27% cited the COVID-19 pandemic as motivation to enter the backcountry and 24% lacked formal avalanche education, which is significantly higher than the 14% of established skiers (P<0.0001). CONCLUSIONS: Influenced by factors related to COVID-19, reported backcountry use increased during the pandemic. Newcomers had a lower level of avalanche education and less confidence in evaluating terrain. Because 80% of participants were recruited from avalanche safety or education websites, this likely underestimates skiers lacking avalanche awareness or education and is further limited by the nature of online surveys.

Profiling of Fusarium head blight resistance QTL haplotypes through molecular markers, genotyping-by-sequencing, and machine learning.

KEY MESSAGE: Marker-assisted selection is important for cultivar development. We propose a system where a training population genotyped for QTL and genome-wide markers may predict QTL haplotypes in early development germplasm. Breeders screen germplasm with molecular markers to identify and select individuals that have desirable haplotypes. The objective of this research was to investigate whether QTL haplotypes can be accurately predicted using SNPs derived by genotyping-by-sequencing (GBS). In the SunGrains program during 2020 (SG20) and 2021 (SG21), 1,536 and 2,352 lines submitted for GBS were genotyped with markers linked to the Fusarium head blight QTL: Qfhb.nc-1A, Qfhb.vt-1B, Fhb1, and Qfhb.nc-4A. In parallel, data were compiled from the 2011-2020 Southern Uniform Winter Wheat Scab Nursery (SUWWSN), which had been screened for the same QTL, sequenced via GBS, and phenotyped for: visual Fusarium severity rating (SEV), percent Fusarium damaged kernels (FDK), deoxynivalenol content (DON), plant height, and heading date. Three machine learning models were evaluated: random forest, k-nearest neighbors, and gradient boosting machine. Data were randomly partitioned into training-testing splits. The QTL haplotype and 100 most correlated GBS SNPs were used for training and tuning of each model. Trained machine learning models were used to predict QTL haplotypes in the testing partition of SG20, SG21, and the total SUWWSN. Mean disease ratings for the observed and predicted QTL haplotypes were compared in the SUWWSN. For all models trained using the SG20 and SG21, the observed Fhb1 haplotype estimated group means for SEV, FDK, DON, plant height, and heading date in the SUWWSN were not significantly different from any of the predicted Fhb1 calls. This indicated that machine learning may be utilized in breeding programs to accurately predict QTL haplotypes in earlier generations.

Identification of a cis-sex chromosome transition in banded geckos (Coleonyx, Eublepharidae, Gekkota).

Sex-determination systems are highly variable amongst vertebrate groups, and the prevalence of genomic data has greatly expanded our knowledge of how diverse some groups truly are. Gecko lizards are known to possess a variety of sex-determination systems, and each new study increases our knowledge of this diversity. Here, we used RADseq to identify male-specific markers in the banded gecko Coleonyx brevis, indicating this species has a XX/XY sex-determination system. Furthermore, we show that these sex-linked regions are not homologous to the XX/XY sex chromosomes of two related Coleonyx species, C. elegans and C. mitratus, suggesting that a cis-sex chromosome turnover-a change in sex chromosomes without a concomitant change in heterogamety-has occurred within the genus. These findings demonstrate the utility of genome-scale data to uncover novel sex chromosomes and further highlight the diversity of gecko sex chromosomes.

Accounting for heading date gene effects allows detection of small-effect QTL associated with resistance to Septoria nodorum blotch in wheat.

In humid and temperate areas, Septoria nodorum blotch (SNB) is a major fungal disease of common wheat (Triticum aestivum L.) in which grain yield is reduced when the pathogen, Parastagonospora nodorum, infects leaves and glumes during grain filling. Foliar SNB susceptibility may be associated with sensitivity to P. nodorum necrotrophic effectors (NEs). Both foliar and glume susceptibility are quantitative, and the underlying genetics are not understood in detail. We genetically mapped resistance quantitative trait loci (QTL) to leaf and glume blotch using a double haploid (DH) population derived from the cross between the moderately susceptible cultivar AGS2033 and the resistant breeding line GA03185-12LE29. The population was evaluated for SNB resistance in the field in four successive years (2018-2021). We identified major heading date (HD) and plant height (PH) variants on chromosomes 2A and 2D, co-located with SNB escape mechanisms. Five QTL with small effects associated with adult plant resistance to SNB leaf and glume blotch were detected on 1A, 1B, and 6B linkage groups. These QTL explained a relatively small proportion of the total phenotypic variation, ranging from 5.6 to 11.8%. The small-effect QTL detected in this study did not overlap with QTL associated with morphological and developmental traits, and thus are sources of resistance to SNB.

Evaluation of the LIGHT Curriculum: An African American Church-Based Curriculum for Training Lay Health Workers to Support Advance Care Planning, End-of-Life Decision Making, and Care.

Background: Lay health workers (LHWs) engaging African Americans in conversations about advance care planning (ACP) often have felt unprepared for the challenges of communicating with patients as they approach the end of life. We developed a church-based training curriculum, LIGHT (Listening, Identifying, Guiding, Helping, Translating), in response to this need. Objectives: To evaluate the LIGHT Curriculum by assessing its impact on knowledge, beliefs and attitudes, and self-efficacy of the learners; describing their assessment of the classroom component of the training; and describing their visit activities, and perceptions derived during client visits. Design: prospective, descriptive, pre- and post-training evaluation. Settings/Subjects: Thirty-seven LHWs (Comfort Care Supporters [CCSs]) from three African American Churches (United States). Measurements: knowledge, beliefs and attitudes, assessment of classroom training, self-efficacy, visit activities, and perceptions. Results: Pre-to-post knowledge scores (range 0-26) increased by a mean of 5.23, p < 0.0001. Agreement with favorable beliefs about palliative and hospice care (HC) did not change significantly post-training. Disagreement with unfavorable beliefs about hospice increased, most notably, the belief that hospice means a place where people go to die (43% to 87%, p = 0.003) and HC means giving up (77% to 93%, p = 0.03). Post-training, 94% of the CCSs felt prepared to function in their roles. The CCSs who visited clients demonstrated the ability to engage clients and families in conversations about issues important to ACP, end-of-life decision making and care, and the ability to identify relevant benefits and challenges of their roles. Conclusions: LHWs, trained using the LIGHT Curriculum, can acquire the knowledge and self-efficacy necessary to support African American clients with ACP, end-of-life decision making, and end-of-life care.

A Reexamination of the Herpetofauna of Oaxaca, Mexico: Composition Update, Physiographic Distribution, and Conservation Commentary.

A substantial number of changes to the composition of the herpetofauna of the Mexican state of Oaxaca, including taxonomic additions and deletions, have occurred in the five years since our original assessment of this region. These changes now establish a herpetofauna of 480 species for the state. A number of taxonomic and nomenclatural changes involving the Oaxacan herpetofauna also are discussed. Updated patterns of physiographic distribution, endemism, and conservation status of the members of the state herpetofauna are examined.

Powder Fever and Its Impact on Decision-Making in Avalanche Terrain.

We examined the effect of emotions, associated with "powder fever", on decision-making in avalanche terrain. BACKGROUND: Skiing in avalanche terrain is a voluntary activity that exposes the participant to potentially fatal risk. Impaired decision-making in this context can therefore have devastating results, often with limited prior corrective feedback and learning opportunities. Previous research has suggested that arousal caused by emotions affects risk assessment and intentions to engage in risky behavior. We propose that powder fever may induce similar responses. METHODS: We used the following two experimental methods: laboratory studies with visual visceral stimuli (ski movies) and a field study with real stimuli (skiing exciting terrain). We evaluated the effect of emotions on attention, risk assessment, and willingness to expose oneself and others to risk. RESULTS: Both the laboratory studies and the field study showed that skiing-related stimuli had a relatively strong effect on reported emotions. However, we found very few significant effects on decision-making or assessment of risk. CONCLUSIONS: Skiing activities make people happier. However, despite the clear parallels to sexual arousal, powder fever does not appear to significantly impair decision-making in our study. More research on the effects of powder fewer on milder forms of risk-taking behavior is needed.

Characterizing the oligogenic architecture of plant growth phenotypes informs genomic selection approaches in a common wheat population.

BACKGROUND: Genetic variation in growth over the course of the season is a major source of grain yield variation in wheat, and for this reason variants controlling heading date and plant height are among the best-characterized in wheat genetics. While the major variants for these traits have been cloned, the importance of these variants in contributing to genetic variation for plant growth over time is not fully understood. Here we develop a biparental population segregating for major variants for both plant height and flowering time to characterize the genetic architecture of the traits and identify additional novel QTL. RESULTS: We find that additive genetic variation for both traits is almost entirely associated with major and moderate-effect QTL, including four novel heading date QTL and four novel plant height QTL. FT2 and Vrn-A3 are proposed as candidate genes underlying QTL on chromosomes 3A and 7A, while Rht8 is mapped to chromosome 2D. These mapped QTL also underlie genetic variation in a longitudinal analysis of plant growth over time. The oligogenic architecture of these traits is further demonstrated by the superior trait prediction accuracy of QTL-based prediction models compared to polygenic genomic selection models. CONCLUSIONS: In a population constructed from two modern wheat cultivars adapted to the southeast U.S., almost all additive genetic variation in plant growth traits is associated with known major variants or novel moderate-effect QTL. Major transgressive segregation was observed in this population despite the similar plant height and heading date characters of the parental lines. This segregation is being driven primarily by a small number of mapped QTL, instead of by many small-effect, undetected QTL. As most breeding populations in the southeast U.S. segregate for known QTL for these traits, genetic variation in plant height and heading date in these populations likely emerges from similar combinations of major and moderate effect QTL. We can make more accurate and cost-effective prediction models by targeted genotyping of key SNPs.

A review of the introduced herpetofauna of Mexico and Central America, with comments on the effects of invasive species and biosecurity methodology.

Among the principal causes producing detrimental effects on global biodiversity are introductions of alien species. Very few attempts to control introduced amphibians and reptiles in Middle America (Mexico and Central America) can be identified, so listings are provided for 24 exotic species, 16 translocated species, and 11 species that were removed from the introduced species listing because of lack of substantiating evidence that they are from established populations. Biosecurity methods are also identified that can be applied for preventing, controlling, and managing introduced and especially invasive species.

ResumenEntre las principales causas que producen efectos perjudiciales sobre la biodiversidad mundial se encuentran la introducción de especies exóticas. Se pueden identificar muy pocos intentos de controlar anfibios y reptiles introducidos en América Central (México y América Central), por lo que proporcionamos listas de 24 especies exóticas, 16 especies translocadas y 11 especies que eliminamos de la lista de especies introducidas debido a la falta de evidencia que corrobore que provienen de poblaciones establecidas. También identificamos métodos de bioseguridad que se pueden aplicar para prevenir, controlar y gestionar especies introducidas y especialmente invasoras.

Analysis of the primary sources of quantitative adult plant resistance to stripe rust in U.S. soft red winter wheat germplasm.

Stripe rust, or yellow rust (Puccinia striiformis Westend. f. sp. tritic), is a disease of wheat (Triticum aestivum L.) historically causing significant economic losses in cooler growing regions. Novel isolates of stripe rust with increased tolerance for high temperatures were detected in the United States circa 2000. This increased heat tolerance puts geographic regions, such as the soft red winter wheat (SRWW) growing region of the southeastern United States, at greater risk of stripe rust induced losses. In order to identify sources of stripe rust resistance in contemporary germplasm, we conducted genome-wide association (GWA) studies on stripe rust severity measured in two panels. The first consisted of 273 older varieties, landraces, and some modern elite breeding lines and was evaluated in environments in the U.S. Pacific Northwest and the southeastern United States. The second panel consisted of 588 modern, elite SRWW breeding lines and was evaluated in four environments in Arkansas and Georgia. The analyses identified three major resistance loci on chromosomes: 2AS (presumably the 2NS:2AS alien introgression from Aegilops ventricosa Tausch; syn. Ae. caudata L.), 3BS, and 4BL. The 4BL locus explained a greater portion of variance in resistance than either the 2AS or 3BS loci in southeastern environments. However, its effects were unstable across different environments and sets of germplasm, possibly a result of its involvement in epistatic interactions. Relatively few lines carry resistance alleles at all three loci, suggesting that there is a pre-existing reservoir of enhanced stripe rust resistance that may be further exploited by regional breeding programs.

Faith Beliefs of African American Church Leaders Are Aligned With the Principles of Palliative and Hospice Care: A Community-Based Assessment and Intervention.

BACKGROUND: African American (AA) church leaders often advise AAs with serious and life-limiting illnesses (LLIs). OBJECTIVES: 1) determine beliefs of AA church leaders about palliative care and hospice care (PCHC), 2) assess association of participants' attitude about encouraging a loved one to learn about PCHC with whether PC or HC is consistent with faith beliefs and can reduce suffering and bring comfort, and 3) evaluate an interactive, educational intervention. DESIGN: prospective, one group, pre and post assessment of beliefs and attitudes Settings/Subjects: 100 church leaders from 3 AA Churches and one AA Church Consortium. RESULTS: At baseline, participants held more receptive beliefs about HC than about PC. Those who reported knowing the meaning of PC believed PC is consistent with their faith (81% vs 28%, phi=.53) and can reduce suffering and bring comfort (86% vs 38%, phi =.50). Participants who believed PC was consistent with their faith were more likely to encourage a loved one with a LLI to learn about PCHC than did participants who did not (100% vs 77%, phi =.39, p < 0.001). Post intervention, more participants: 1) perceived that they knew the meaning of PC (48% vs 96%), 2) viewed PC as consistent with their faith (58% vs. 94%), and 3) viewed PC as a means to reduce suffering and bring comfort (67% vs 93%) with a p < 0.0001 for each item. The post intervention results for HC were variable. CONCLUSIONS: Faith beliefs of AA Church leaders may be aligned with the principles of PCHC.

Lessons Learned from the Medical University of South Carolina Transdisciplinary Collaborative Center (TCC) in Precision Medicine and Minority Men's Health.

The Transdisciplinary Collaborative Center (TCC) in Precision Medicine for Minority Men's Health was established at the Medical University of South Carolina (MUSC) in 2015 to address disparities in the translation of precision medicine approaches among racial minority groups. This regional consortium focuses on three primary areas: (1) the development of a consortium of regional and national partners, (2) conducting transdisciplinary research examining synergistic effects of biological, social, physiological, and clinical determinants of chronic disease risks and outcomes, and (3) dissemination and implementation of precision medicine approaches, with an emphasis on reducing disparities in health care and outcomes among minority men. Given consistent calls to better translate precision medicine approaches and the focus of this consortium on addressing disparities among minority men, we provide an overview of our experience in developing the MUSC TCC, including barriers and facilitators to conducting translational research on minority men's health issues in the context of precision medicine. Lessons learned and areas for improvement include providing enough time to create consistent partnerships and community engagement to improve recruitment and retention, identifying unique ways to engage diverse partners from across the region and nation, and better approaches to dissemination and communication for large partnerships focusing on precision medicine.

A novel adult plant leaf rust resistance gene Lr2K38 mapped on wheat chromosome 1AL.

Soft red winter wheat (SRWW) cultivar AGS 2038 has a high level of seedling and adult plant leaf rust (LR) resistance. To map and characterize LR resistance in AGS 2038, a recombinant inbred line (RIL) population consisting of 225 lines was developed from a cross between AGS 2038 and moderately resistant line UGA 111729. The parents and RIL population were phenotyped for LR response in three field environments at Plains and Griffin, GA, in the 2017-2018 and 2018-2019 growing seasons, one greenhouse environment at the adult-plant stage, and at seedling stage. The RIL population was genotyped with the Illumina iSelect 90K SNP marker array, and a total of 7667 polymorphic markers representing 1513 unique loci were used to construct a linkage map. Quantitative trait loci (QTL) analysis detected six QTL, QLr.ags-1AL, QLr.ags-2AS, QLr.ags-2BS1, QLr.ags-2BS2, QLr.ags-2BS3, and QLr.ags-2DS, for seedling and adult plant LR resistance. Of these, the major adult plant leaf rust resistance QTL, QLr.ags-1AL, was detected on all field and greenhouse adult plant tests and explained up to 34.45% of the phenotypic variation. QLr.ags-1AL, tightly flanked by IWB20487 and IWA4022 markers, was contributed by AGS 2038. Molecular marker analysis using a diagnostic marker linked to Lr59 showed that QLr.ags-1AL was different from Lr59, the only known LR resistance gene on 1AL. Therefore, the QTL was temporarily designated as Lr2K38. Lr2K38-linked marker IWB20487 was highly polymorphic among 30 SRWW lines and should be useful for selecting the Lr2K38 in wheat breeding programs.

Multi-Trait Genomic Prediction of Yield-Related Traits in US Soft Wheat under Variable Water Regimes.

The performance of genomic prediction (GP) on genetically correlated traits can be improved through an interdependence multi-trait model under a multi-environment context. In this study, a panel of 237 soft facultative wheat (Triticumaestivum L.) lines was evaluated to compare single- and multi-trait models for predicting grain yield (GY), harvest index (HI), spike fertility (SF), and thousand grain weight (TGW). The panel was phenotyped in two locations and two years in Florida under drought and moderately drought stress conditions, while the genotyping was performed using 27,957 genotyping-by-sequencing (GBS) single nucleotide polymorphism (SNP) makers. Five predictive models including Multi-environment Genomic Best Linear Unbiased Predictor (MGBLUP), Bayesian Multi-trait Multi-environment (BMTME), Bayesian Multi-output Regressor Stacking (BMORS), Single-trait Multi-environment Deep Learning (SMDL), and Multi-trait Multi-environment Deep Learning (MMDL) were compared. Across environments, the multi-trait statistical model (BMTME) was superior to the multi-trait DL model for prediction accuracy in most scenarios, but the DL models were comparable to the statistical models for response to selection. The multi-trait model also showed 5 to 22% more genetic gain compared to the single-trait model across environment reflected by the response to selection. Overall, these results suggest that multi-trait genomic prediction can be an efficient strategy for economically important yield component related traits in soft wheat.

LIGHT: A Church-Based Curriculum for Training African American Lay Health Workers to Support Advance Care Planning and End-of-Life Decision-Making.

Purpose: African Americans with life-limiting illnesses experience significant health inequities. Lay health workers (LHWs) may help overcome existing challenges of communicating with African Americans about advance care planning (ACP) and end-of-life decision-making. Church-based LHWs have some advantages over other LHWs but no curriculum exists to fully prepare them. This article describes the development, content, format, and implementation of a curriculum designed to meet this need. Methods: We created a church-based curriculum to train African American, LHWs as communications-facilitators who can support persons with life-limiting illnesses, not only with ACP but also with issues that arise as illnesses progress. Learners are church members whom we call comfort care supporters. The curriculum organizes the LHW interactions with clients by the mnemonic LIGHT: Listening, Identifying, Guiding, Helping, and Translating. Results: The final curriculum consists of three parts: (1) a 26-h classroom component delivered in nine modules organized around eight themes: meaning and prognosis of a life-limiting illness, spirituality and the meaning of death, understanding the dying process, major decisions and choices, goals of care, end-of-life services, and resources, intrafamily communication, and role and activities of the LHW; (2) a visit component; and (3) experiential, case-based discussions during monthly meetings. Conclusions: LHWs may improve quality of care and thus reduce health inequities at the end-of-life. Preparing LHWs for conversations about ACP is necessary but insufficient. This curriculum also prepares LHWs to attend to the spiritual needs of clients and to support clients with their other needs as their illness progresses.

Effects of human-made resource hotspots on seasonal spatial strategies by a desert pitviper.

Habitat heterogeneity and local resource distribution play key roles in animal search patterns. Optimal strategies are often considered for foraging organisms, but many of the same predictions are applicable to mate searching. We quantified movement and space use by a pitviper to test whether Native Habitats (NH) and human-made Resource Hotspots (RH) facilitate alternative seasonal spatial strategies as a result of critical resources, including potential mating partners, being widely dispersed in NH and clustered in RH. Independent of habitat category, seasonal patterns resembled an intermediate mating system with elements of prolonged male mate-searching and female-defense. However, individuals using primarily NH or RH exhibited alternative strategies. NH rattlesnakes displayed greater movement and larger home ranges than RH rattlesnakes across behavioral seasons. NH males increased movement distances and home ranges during the mating season, while RH males displayed minimal or no seasonal shifts. NH females also elevated movement distances during the mating season, while RH females showed no significant seasonal differences. Despite contrasting spatial patterns, mating success and female-defense effort were not significantly affected by habitat category. This unique study system highlights the potential for interactions among sexual selection, habitat heterogeneity, and behavioral plasticity to facilitate divergent search tactics within populations.

CPAP Adherence May Slow 1-Year Cognitive Decline in Older Adults with Mild Cognitive Impairment and Apnea.

BACKGROUND/OBJECTIVES: Obstructive sleep apnea (OSA) has been linked to an increased risk for Alzheimer's disease (AD), but little prospective evidence exists on the effects of OSA treatment in preclinical AD. The objective was to determine if continuous positive airway pressure (CPAP) treatment adherence, controlling for baseline differences, predicts cognitive and everyday function after 1 year in older adults with mild cognitive impairment (MCI) and to determine effect sizes for a larger trial. DESIGN: Quasi-experimental pilot clinical trial with CPAP adherence defined as CPAP use 4 hours or more per night over 1 year. SETTING: Sleep and geriatric clinics and community. PARTICIPANTS: Older adults, aged 55 to 89 years, with an apnea-hypopnea index of 10 or higher participated: (1) MCI, OSA, and CPAP adherent (MCI +CPAP), n = 29; and (2) MCI, OSA, CPAP nonadherent (MCI -CPAP), n = 25. INTERVENTION: CPAP. MEASUREMENTS: The primary cognitive outcome was memory (Hopkins Verbal Learning Test-Revised), and the secondary cognitive outcome was psychomotor/cognitive processing speed (Digit Symbol subtest from the Wechsler Adult Intelligence Scale Substitution Test). Secondary function and progression measures were the Everyday Cognition, Alzheimer's Disease Cooperative Study-Clinical Global Impression of Change Scale, and Clinical Dementia Rating. RESULTS: Statistically significant improvements in psychomotor/cognitive processing speed in the MCI +CPAP group vs the MCI -CPAP group were observed at 1 year after adjustment for age, race, and marital status (parameter estimate = 1.68; standard error = 0.47; 95% confidence interval = 0.73-2.62), with a 6-month effect size (ES) of 0.46 and a 1-year ES of 1.25. There were small to moderate ESs for memory (ES 0.20, 6 mo), attention (ES 0.25, 1 y), daytime sleepiness (ES 0.33, 6 mo and ES 0.22, 1 y), and everyday function (ES 0.50, 6 mo) favoring the MCI +CPAP group vs the MCI -CPAP group. CONCLUSION: Controlling for baseline differences, 1 year of CPAP adherence in MCI +OSA significantly improved cognition, compared with a nonadherent control group, and may slow the trajectory of cognitive decline. TRIAL REGISTRATION NUMBER: Memories; NCT01482351; https://clinicaltrials.gov/ct2/show/NCT01482351?cond=MCI+and+OSA&rank=1 J Am Geriatr Soc 67:558-564, 2019.

Training population selection and use of fixed effects to optimize genomic predictions in a historical USA winter wheat panel.

KEY MESSAGE: The optimization of training populations and the use of diagnostic markers as fixed effects increase the predictive ability of genomic prediction models in a cooperative wheat breeding panel. Plant breeding programs often have access to a large amount of historical data that is highly unbalanced, particularly across years. This study examined approaches to utilize these data sets as training populations to integrate genomic selection into existing pipelines. We used cross-validation to evaluate predictive ability in an unbalanced data set of 467 winter wheat (Triticum aestivum L.) genotypes evaluated in the Gulf Atlantic Wheat Nursery from 2008 to 2016. We evaluated the impact of different training population sizes and training population selection methods (Random, Clustering, PEVmean and PEVmean1) on predictive ability. We also evaluated inclusion of markers associated with major genes as fixed effects in prediction models for heading date, plant height, and resistance to powdery mildew (caused by Blumeria graminis f. sp. tritici). Increases in predictive ability as the size of the training population increased were more evident for Random and Clustering training population selection methods than for PEVmean and PEVmean1. The selection methods based on minimization of the prediction error variance (PEV) outperformed the Random and Clustering methods across all the population sizes. Major genes added as fixed effects always improved model predictive ability, with the greatest gains coming from combinations of multiple genes. Maximum predictabilities among all prediction methods were 0.64 for grain yield, 0.56 for test weight, 0.71 for heading date, 0.73 for plant height, and 0.60 for powdery mildew resistance. Our results demonstrate the utility of combining unbalanced phenotypic records with genome-wide SNP marker data for predicting the performance of untested genotypes.

Genome-Wide Association Study of a Worldwide Collection of Wheat Genotypes Reveals Novel Quantitative Trait Loci for Leaf Rust Resistance.

CORE IDEAS: The emergence of new virulent Puccinia triticina races requires a continuous search for novel sources of resistance to combat leaf rust (LR) disease Twenty-two wheat genotypes resistant to four P. triticina races were identified in this study A genome-wide association study detected 11 quantitative trait loci for LR resistance; five of them were detected on genomic regions where no LR resistant genes have been detected. Wheat (Triticum aestivum L.) production worldwide is being challenged by several biotic and abiotic factors. Leaf rust (LR), caused by Puccinia triticina, is a major biotic constraint of wheat production worldwide. Genetic resistance is the most efficient and cost-effective way to control LR. Seventy-nine LR resistance genes have been identified to date but the frequent emergence of new virulent P. triticina races every year demands a constant search for new sources of resistance with novel quantitative trait loci (QTL) or genes. The objectives of this study were to identify putative novel sources of effective resistance against the current prevalent races of P. triticina in the southeast United States and to map genomic loci associated with LR resistance via a genome-wide association study (GWAS) approach. Evaluation of 331 diverse wheat genotypes against four prevalent P. triticina races (MFGKG, MBTNB, MCTNB, and TCRKG) revealed that the majority of the genotypes were susceptible and only 22 genotypes (6.6%) were resistant to all four P. triticina races. The GWAS detected 11 QTL on nine chromosomes for LR resistance. Of these, six QTL were identified in the vicinity of known genes or QTL; therefore, more studies are warranted to determine their relationship. Five QTL (QLr.uga-1AL, QLr.uga-4AS, QLu.uga-5AS, QLr.uga-5AL, and QLr.uga-7AS) were identified on genomic regions where no LR resistance genes have been identified in wheat, representing potential novel loci for LR resistance. The highly resistant wheat genotypes and novel QTL reported in this study could be used in breeding programs to improve LR resistance.