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Three novel crayfish-infecting nudiviruses from crayfish in North America represent the first genomic confirmation of nudiviruses in crayfish: Faxonius propinquus nudivirus (FpNV), Faxonius rusticus nudivirus (FrNV), and Faxonius virilis nudivirus (FvNV). Histopathology and electron microscopy revealed nuclear infections, including nuclear hypertrophy in hepatopancreatic epithelial cells and the presence of membrane-bound bacilliform virions. Metagenomic sequencing resulted in complete circular genome assembly, and phylogenetic analyses (based on nudivirus core genes) placed these viruses within the unofficial Epsilonnudivirus genus. One of the nudiviruses was detected in the antennal gland of its host, and another is correlated with invasive crayfish decline in one infected lake ecosystem - suggesting a potential route for viral transmission through water, and possible population level impact. This study highlights the importance of genomic and ecological data in elucidating the diversity and evolutionary relationships of the Nudiviridae, while expanding their known diversity and range of host species.
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Astacoidea , Genoma Viral , Nudiviridae , Filogenia , Animales , Astacoidea/virología , Nudiviridae/genética , Nudiviridae/aislamiento & purificación , América del Norte , MetagenómicaRESUMEN
Background: Cannabis use is associated with altered processing of external (exteroceptive) and internal (interoceptive) sensory stimuli. However, little research exists on whether subjective experiences of these processes are altered in people who frequently use cannabis. Altered exteroception may influence externally oriented attention, whereas interoceptive differences have implications for intoxication, craving, and withdrawal states.Objectives: The goal of the current study was to investigate subjective experiences of exteroceptive sensory gating and interoception in people frequently using cannabis. We hypothesized subjective impairments in sensory gating and elevations in affect-related interoceptive awareness; furthermore, such deviations would relate to cannabis use patterns.Methods: This cross-sectional study of community adults 18-40 years old included 72 individuals (50% female) who used cannabis at least twice a week (not intoxicated during study) and 78 individuals who did not use cannabis (60% female). Participants completed the Sensory Gating Inventory and the Multidimensional Assessment of Interoceptive Awareness-2 surveys. People using cannabis completed surveys on cannabis use patterns. Analyses tested group differences and associations with cannabis use.Results: People using cannabis reported impaired sensory gating (d = 0.37-0.44; all p values < 0.05) and elevations of interoceptive awareness related to detection and affect (d = 0.21-0.61; all p values < 0.05). Problematic cannabis use was associated with increased sensory gating impairments (r = 0.37, p < .05). Interoceptive awareness was unrelated to cannabis use variables.Conclusion: These findings extend literature on subjective experiences of sensory processing in people using cannabis. Findings may inform inclusion of external attentional tendencies and internal bodily awareness in assessments of risk and novel treatment approaches.
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Interocepción , Autoinforme , Filtrado Sensorial , Humanos , Femenino , Adulto , Masculino , Interocepción/fisiología , Adulto Joven , Estudios Transversales , Adolescente , Filtrado Sensorial/fisiología , Filtrado Sensorial/efectos de los fármacos , Uso de la Marihuana/psicología , Concienciación/fisiologíaRESUMEN
Hybridisation can be an important driver of evolutionary change, but hybridisation with invasive species can have adverse effects on native biodiversity. While hybridisation has been documented across taxa, there is limited understanding of ecological factors promoting patterns of hybridisation and the spatial distribution of hybrid individuals. We combined the results of ecological niche modelling (ENM) and restriction site-associated DNA sequencing to test theories of niche conservatism and biotic resistance on the success of invasion, admixture, and extent of introgression between native and non-native fishes. We related Maxent predictions of habitat suitability based on the native ranges of invasive Eastern Banded Killifish (Fundulus diaphanus diaphanus Lesueur 1817) and native Western Banded Killifish (Fundulus diaphanus menona Jordan and Copeland 1877) to admixture indices of individual Banded Killifish. We found that Eastern Banded Killifish predominated at sites predicted as suitable from their ENM, consistent with niche conservatism. Admixed individuals were more common as Eastern Banded Killifish habitat suitability declined. We also found that Eastern Banded Killifish were most common at sites closest to the presumed source of this invasion, whereas the proportion of admixed individuals increased with distance from the source of invasion. Lastly, we found little evidence that habitat suitability for Western Banded Killifish provides biotic resistance from either displacement by, or admixture with, invasive Eastern Banded Killifish. Our study demonstrates that ENMs can inform conservation-relevant outcomes between native and invasive taxa while emphasising the importance of protecting isolated Western Banded Killifish populations from invasive conspecifics.
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Ecosistema , Fundulidae , Especies Introducidas , Animales , Fundulidae/genética , Hibridación Genética , Genética de Población , Introgresión Genética , Análisis de Secuencia de ADN , BiodiversidadRESUMEN
RATIONALE: Cannabis is the most widely used illicit substance in the USA and is often reportedly used for stress reduction. Indeed, cannabinoids modulate signaling of the hypothalamic-pituitary-adrenal axis and sympathetic nervous system. However, the role of biological sex in this interaction between cannabis use and stress is poorly understood, despite sex differences in neurobiological stress responsivity, endocannabinoid signaling, and clinical correlates of cannabis use. OBJECTIVE: The study aims to examine the role of biological sex in multisystem stress responsivity in cannabis users. METHODS: Frequent cannabis users (> 3 times/week, n = 48, 52% male) and non-users (n = 41, 49% male) participated in an acute psychosocial stress paradigm. Saliva was collected at eight timepoints and analyzed for hypothalamic-pituitary-adrenal (cortisol) and sympathetic (alpha-amylase) indices of stress responsivity, and basal estradiol. Subjective ratings of negative affect, including distress, were collected at three timepoints. RESULTS: Cannabis users showed blunted pre-to-post-stress cortisol reactivity. Female cannabis users demonstrated greater blunted cortisol reactivity than their male counterparts. Sex moderated the effect of cannabis use on alpha-amylase responsivity over time, wherein female cannabis users showed flattened alpha-amylase responses across the stressor compared to male cannabis users and both non-user groups. Qualitatively, female cannabis users demonstrated the greatest pre-to-post-stress change in subjective distress. Differences in stress responding were not explained by estradiol or distress intolerance. CONCLUSIONS: Biological sex impacts multisystem stress responding in cannabis users. Paradoxically, female cannabis users showed the least physiological, but greatest subjective, responses to the stressor. Further research into sex differences in the effects of cannabis use is warranted to better understand mechanisms and clinical implications.
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Cannabis , Alucinógenos , Sistema Hipotálamo-Hipofisario , Hidrocortisona , Caracteres Sexuales , Estrés Psicológico/psicología , Sistema Hipófiso-Suprarrenal , alfa-Amilasas , Sistema Nervioso Simpático , SalivaRESUMEN
Soil disinfection using high temperatures via steam is a promising approach to manage plant pathogens, pests, and weeds. Soil steaming is a viable option for growers who are moving away from dependence on chemical soil fumigants, especially in plant nursery or high tunnel environments. However, there are few studies that investigate how soil steaming causes substantial disturbance to the soil by killing both target pathogens and other soil biota. Steaming treatments also change the trajectory of the soil microbiome as it reassembles over time. Growers are interested in the health of soils after using steam-disinfection, especially if a virulent pathogen colonizes the soil and then flourishes in a situation where there are very few microbes to suppress its growth. Should recruitment of a virulent pathogen occur in the soil, this could have devasting effects on seed germination, seedling establishment and survival. Beneficial microbes are often used to prevent the colonization of plant pathogens, especially after a soil-steaming event. Here, we experimentally test how soil fungal communities assemble after steaming disinfection. We introduce to steam-treated soil Fusarium solani, an important fungal pathogen of soybean and Trichoderma harzianum, a known beneficial fungus used for soilborne pathogen suppression. Results show that F. solani significantly affects the relative abundance and diversity of the soil fungal microbiome, however, T. harzianum does not mitigate the amount of F. solani in the steam treated soil. Within the T. harzianum microbial addition, the soil fungal communities were similar to the control (steaming only). This result suggests inoculating the soil with T. harzianum does not drastically alter the assembly trajectory of the soil fungal microbiome. Other soil amendments such as a combination of Trichoderma spp. or other genera could suppress F. solani growth and shift soil microbiome composition and function post-steaming, however, more experimental research is needed.
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Primary burrowing crayfishes face high extinction risk, but are challenging to study, manage, and conserve due to their difficult-to-sample habitat (i.e., terrestrial burrows) and low population densities. We apply here a variety of methods to characterize the distribution, habitat associations, and conservation status of the Boston Mountains Crayfish Cambarus causeyi (Reimer, 1966), an endemic burrowing crayfish found only in the Ozark Mountains of Arkansas, United States. We used species distribution modeling (SDM) on historic occurrence records to characterize the distribution and macro-scale habitat associations of this species. We then ground-truthed SDM predictions with conventional sampling, modeled fine-scale habitat associations with generalized linear models (GLM), and lastly developed and tested an environmental DNA (eDNA) assay for this species in comparison to conventional sampling. This represents, to our knowledge, the first successful eDNA assay for a terrestrial burrowing crayfish. Our MaxEnt-derived SDM found a strong effect of average annual precipitation on the historic distribution of C. causeyi, which occurred most frequently at locations with moderately high average annual precipitation (140-150 cm/yr) within our study region. Cambarus causeyi was difficult to detect by conventional sampling in 2019 and 2020, found at only 9 of 51 sites (17.6%) sampled by searching for and manually excavating crayfish burrows. Surprisingly, habitat suitability predicted from our MaxEnt models was not associated with contemporary C. causeyi occurrences per GLMs. Instead, C. causeyi presence was negatively associated with both sandy soils and the presence of other burrowing crayfish species. Poor SDM performance in this instance was likely caused by the omission of high resolution fine-scale habitat data (e.g., soils) and biotic interactions from MaxEnt models. Finally, our eDNA assay detected C. causeyi from six of 25 sites (24.0%) sampled in 2020, out-performing conventional surveys by burrow excavation for this species. Given the difficulty of studying primary burrowing crayfishes and their high conservation need, we propose that eDNA may become an increasingly important monitoring tool for C. causeyi and similar species.
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Astacoidea , Ecosistema , Animales , Astacoidea/genética , Suelo , Arena , América del NorteRESUMEN
A central focus of invasive species research has been on human efforts to eradicate invaders or reduce their abundance to mitigate the worst of their impacts. In some cases, however, populations of invasive species decline without human intervention, which may inform management responses to these invaders. Such is the case of the invasive rusty crayfish (Faxonius rusticus) in northern Wisconsin, USA, where systematic population monitoring since 1975 has revealed population declines in approximately half of the lakes surveyed. Population declines of invasive species without human intervention remain understudied, but there is even less research on how communities respond following such declines. Using 10 lakes in Vilas County, Wisconsin, we investigated community recovery of habitat (macrophytes) and prey (freshwater snails) of F. rusticus following up to 33 years of declines of this invader in some lakes using a dataset with a rare, long-term span over which consistent data were collected (1987, 2002, 2011, and 2020). We compared community responses in lakes where F. rusticus populations reached a peak and subsequently declined (boom-bust lakes) and lakes where our dataset only captured the decline of F. rusticus (bust lakes) to reference lakes with consistently high or low crayfish abundance over time. We found partial recovery of macrophytes and snails in the bust and boom-bust lakes where F. rusticus has declined, with recovery of macrophyte abundance and richness in the boom-bust lakes achieving levels observed in the low-crayfish reference lakes. Snail abundance and richness increased after declines of F. rusticus, though not to the level of the low-crayfish reference lakes, suggesting that snail recovery may lag macrophyte recovery because snails are dependent on macrophytes and associated periphyton for habitat. The recovery we document potentially represents long-term ecosystem resilience of lakes to biological invasions. Our results suggest that lake communities may recover without active restoration interventions after invasive crayfish population declines, although identifying which lakes experience these natural declines remains a priority for future research and management.
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Astacoidea , Ecosistema , Humanos , Animales , Astacoidea/fisiología , Lagos , Alimentos Marinos , Caracoles , Especies IntroducidasRESUMEN
Global climate change and agricultural disturbance often drive freshwater biodiversity changes at the regional level, particularly in the Midwestern US. Agricultural conservation practices have been implemented to reduce sediment and nutrient loading (e.g., crop rotation, cover crops, reduced tillage, and modified fertilizer application) for long-term economic sustainability and environmental resilience. However, the effectiveness of these efforts on freshwater biodiversity is not conclusive. In this study, we used the Kaskaskia River Watershed, Illinois as an example to evaluate how agricultural conservation practices affects both taxonomic and functional diversity under climate changes. The measures of trait-based functional diversity provide mechanistic explanations of biological changes. In specific, we model and predict 1) species richness (SR), 2) functional dispersion (FDis), and 3) functional evenness (FEve). FDis and FEve were based on ecology (life history, habitat preference, and trophic level) and physiology (thermal preference, swimming preference, etc.). The best random-forest regression models showed that flow, temperature, nitrate, and the watershed area were among the top predictors of the three biodiversity measures. We then used the models to predict the changes of SR and FDis under RCP8.5 climate change scenarios. SR and FDis were predicted to decrease in most sites, up to 20 % and 4 % by 2099, respectively. When agricultural conservation practices were considered together with climate changes, the decreasing trends of SR and FDis remained, suggesting climate change outweighed potential agriculture conservation efforts. Thus, climate-change effects on temperature and flow regimes need to be incorporated into the design of agricultural practices for freshwater biodiversity conservation.
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Biodiversidad , Agua Dulce , Agricultura , Ecosistema , Cambio Climático , Conservación de los Recursos NaturalesRESUMEN
Individual specialization within populations is increasingly recognized as important in both ecology and evolution, but researchers working on intraspecific variation in behavior and diet infrequently interact. This may be because individual specialization on diet and behavior was historically difficult to investigate simultaneously on the same individuals. However, approaches like stable isotope analysis that allow hindcasting past field diets for laboratory organisms may provide opportunities to unite these areas of inquiry. Here, we tested the role of intraspecific competition on individual specialization through analysis of both behavior and diet simultaneously. We focused on intraspecific competition as a mechanism that might drive individual specialization of both diet and behavior. We conducted this study in Vilas County, Wisconsin, United States (US), using rusty crayfish Faxonius rusticus from six lakes across a relative abundance gradient. We conducted six assays to measure individual specialization of behavior and used stable isotope analysis to measure individual specialization of diet. We then related both measures of individual specialization to relative abundance of F. rusticus using linear and quadratic models. We found a unimodal relationship between intraspecific competition and individual specialization of diet for F. rusticus, likely because some preferred resources are unavailable to specialize on at the highest densities of this well-studied crayfish invader. Conversely, we found greater support for a linear relationship between individual specialization of behavior and intraspecific competition, perhaps because specialization by behavior is not inherently resource-limited. Our results show that dietary and behavioral specialization may exhibit different responses to increased intraspecific competition, and demonstrate a potential technique that can be used to investigate individual specialization of diet and behavior simultaneously for the same individuals and populations.
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Bereavement is one of the most intense, distressing, and traumatic events an elderly person will experience. The symptom responses to bereavement vary, particularly during the first year. However, the neurobiology underlying the symptom variance in grief is poorly understood. The endocannabinoid signaling (ECS) system is stress-responsive; mounting evidence implicates the central ECS in psychopathology. The current study aimed to investigate the hypothesis that the ECS is abnormal in grief, using circulating eCB concentrations as a biomarker of central ECS. A predominantly older sample of grief participants, within 13 months following the death of a loved one, and healthy comparison (HC) participants were studied. Associations of circulating eCBs with symptom variance in grievers were also examined. A total of 61 (grief: n = 44; HC: n = 17) adults completed cross-sectional clinical assessments and a fasting blood draw. Assessments included the Inventory of Complicated Grief scale; the 17-item Hamilton Depression Rating Scale; and the Hamilton Anxiety scale. Serum eCB concentrations (i.e., N-arachidonoylethanolamine [AEA] and 2-arachidonoylglycerol [2-AG]) were quantified using isotope dilution, liquid chromatography-mass spectrometry. Relative to HC participants, grievers had significantly elevated serum AEA but similar 2-AG concentrations. In grievers, serum AEA concentrations were positively associated with depressive and anxiety symptoms, but only in those with low grief symptoms. These novel findings indicate that elevated circulating eCB concentrations are found following bereavement. The eCB signaling response varies based on the degree of grief severity. Circulating eCB measures may have the potential to serve as biomarkers of prolonged grief disorder.
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Endocannabinoides/análisis , Pesar , Anciano , Anciano de 80 o más Años , Ansiedad/metabolismo , Ansiedad/fisiopatología , Ácidos Araquidónicos/análisis , Ácidos Araquidónicos/sangre , Aflicción , Biomarcadores/sangre , Estudios Transversales , Depresión/metabolismo , Depresión/fisiopatología , Endocannabinoides/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Alcamidas Poliinsaturadas/análisis , Alcamidas Poliinsaturadas/sangreRESUMEN
Environmental DNA (eDNA) is an emerging tool for monitoring invasive and imperiled species, particularly at low densities. However, the factors that control eDNA production, transport, and persistence in aquatic systems remain poorly understood. For example, the extent to which carcasses produce detectable eDNA is unknown. If positive detections are associated with dead organisms, this could confound monitoring for imperiled or invasive species. Here, we present results from one of the first studies to examine carcass eDNA in situ by deploying carcasses of the invasive red swamp crayfish (Procambarus clarkii) in a stream enclosure experiment for 28 days. We predicted that carcasses would initially produce eDNA that would decline over time as carcasses decayed. Unsurprisingly, crayfish carcasses lost biomass over time, but at the conclusion of our experiment much of the carapace and chelae remained. However, no eDNA of P. clarkii was detected in any of our samples at the crayfish density (15 P. clarkii carcasses at â¼615 g of biomass initially), stream flow (520-20,319 L/s), or temperature (â¼14-25 °C) at our site. Subsequent analyses demonstrated that these results were not the consequence of PCR inhibition in our field samples, poor performance of the eDNA assay for intraspecific genetic diversity within P. clarkii, or due to the preservation and extraction procedure used. Therefore, our results suggest that when crayfish are relatively rare, such as in cases of new invasive populations or endangered species, carcasses may not produce detectable eDNA. In such scenarios, positive detections from field studies may be more confidently attributed to the presence of live organisms. We recommend that future studies should explore how biomass, flow, and differences in system (lentic vs. lotic) influence the ability to detect eDNA from carcasses.
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Mechanistically connecting genotypes to phenotypes is a longstanding and central mission of biology. Deciphering these connections will unite questions and datasets across all scales from molecules to ecosystems. Although high-throughput sequencing has provided a rich platform on which to launch this effort, tools for deciphering mechanisms further along the genome to phenome pipeline remain limited. Machine learning approaches and other emerging computational tools hold the promise of augmenting human efforts to overcome these obstacles. This vision paper is the result of a Reintegrating Biology Workshop, bringing together the perspectives of integrative and comparative biologists to survey challenges and opportunities in cracking the genotype to phenotype code and thereby generating predictive frameworks across biological scales. Key recommendations include promoting the development of minimum "best practices" for the experimental design and collection of data; fostering sustained and long-term data repositories; promoting programs that recruit, train, and retain a diversity of talent; and providing funding to effectively support these highly cross-disciplinary efforts. We follow this discussion by highlighting a few specific transformative research opportunities that will be advanced by these efforts.
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Macrodatos , Biología Computacional/métodos , Código Genético , Genotipo , FenotipoRESUMEN
Emerging evidence points to the role of the endocannabinoid system in long-term stress-induced neural remodeling with studies on stress-induced endocannabinoid dysregulation focusing on cerebral changes that are temporally proximal to stressors. Little is known about temporally distal and sex-specific effects, especially in cerebellum, which is vulnerable to early developmental stress and is dense with cannabinoid receptors. Following limited bedding at postnatal days 2-9, adult (postnatal day 70) cerebellar and hippocampal endocannabinoids, related lipids, and mRNA were assessed, and behavioral performance evaluated. Regional and sex-specific effects were present at baseline and following early-life stress. Limited bedding impaired peripherally-measured basal corticosterone in adult males only. In the CNS, early-life stress (1) decreased 2-arachidonoyl glycerol and arachidonic acid in the cerebellar interpositus nucleus in males only; (2) decreased 2-arachidonoyl glycerol in females only in cerebellar Crus I; and (3) increased dorsal hippocampus prostaglandins in males only. Cerebellar interpositus transcriptomics revealed substantial sex effects, with minimal stress effects. Stress did impair novel object recognition in both sexes and social preference in females. Accordingly, the cerebellar endocannabinoid system exhibits robust sex-specific differences, malleable through early-life stress, suggesting the role of endocannabinoids and stress to sexual differentiation of the brain and cerebellar-related dysfunctions.
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Endocannabinoides/metabolismo , Hipocampo , Caracteres Sexuales , Maduración Sexual , Estrés Psicológico , Animales , Femenino , Hipocampo/metabolismo , Hipocampo/patología , Hipocampo/fisiopatología , Masculino , Ratas , Ratas Long-Evans , Estrés Psicológico/metabolismo , Estrés Psicológico/patología , Estrés Psicológico/fisiopatologíaRESUMEN
INTRODUCTION: Symptoms of postconcussive syndrome (PCS) after mild TBI (mTBI) have been shown to resolve quickly, yet new research raises questions about possible long-term effects of this condition. It is not clear how best to address assessment and treatment when someone reports lingering symptoms of PCS. One self-report measure used by the VA and the DoD is the Neurobehavioral Symptom Inventory (NSI), but this measure may be affected by underlying psychiatric symptoms. We investigated whether the NSI is sensitive to mTBI after considering a number of psychiatric and demographic factors. METHODS: This study examined which factors are associated with NSI scores in a Veteran sample (n = 741) that had recently returned from deployment. RESULTS: Post-traumatic stress disorder (PTSD) and depression accounted for most of the variance on the NSI. Although history of mTBI was initially related to NSI, this association was no longer significant after other covariates were considered. CONCLUSIONS: The NSI score was primarily explained by symptoms of PTSD and depression, suggesting that the NSI is not specific to the experience of a brain injury. We recommend cautious interpretation when this measure is used in the chronic phase after mTBI, especially among patients with comorbid depression or PTSD.
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Conmoción Encefálica/complicaciones , Síndrome Posconmocional/complicaciones , Veteranos/estadística & datos numéricos , Adulto , Análisis de Varianza , Conmoción Encefálica/epidemiología , Depresión/clasificación , Depresión/diagnóstico , Depresión/psicología , Femenino , Humanos , Masculino , Síndrome Posconmocional/epidemiología , Escalas de Valoración Psiquiátrica , Psicometría/instrumentación , Psicometría/métodos , Autoinforme , Veteranos/psicologíaRESUMEN
Populations of Phytophthora infestans, the oomycete causal agent of potato late blight in the United States, are predominantly asexual, and isolates are characterized by clonal lineage or asexual descendants of a single genotype. Current tools for clonal lineage identification are time consuming and require laboratory equipment. We previously found that foliar spectroscopy can be used for high-accuracy pre- and postsymptomatic detection of P. infestans infections caused by clonal lineages US-08 and US-23. In this work, we found subtle but distinct differences in spectral responses of potato foliage infected by these clonal lineages in both growth-chamber time-course experiments (12- to 24-h intervals over 5 days) and naturally infected samples from commercial production fields. In both settings, we measured continuous visible to shortwave infrared reflectance (400 to 2,500 nm) on leaves using a portable spectrometer with contact probe. We consistently discriminated between infections caused by the two clonal lineages across all stages of disease progression using partial least squares (PLS) discriminant analysis, with total accuracies ranging from 88 to 98%. Three-class random forest differentiation between control, US-08, and US-23 yielded total discrimination accuracy ranging from 68 to 76%. Differences were greatest during presymptomatic infection stages and progressed toward uniformity as symptoms advanced. Using PLS-regression trait models, we found that total phenolics, sugar, and leaf mass per area were different between lineages. Shortwave infrared wavelengths (>1,100 nm) were important for clonal lineage differentiation. This work provides a foundation for future use of hyperspectral sensing as a nondestructive tool for pathovar differentiation.
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Phytophthora infestans , Solanum tuberosum , Genotipo , Enfermedades de las Plantas , Análisis EspectralRESUMEN
Phytophthora ramorum, cause of sudden oak death and ramorum leaf blight, can persist undetected in infested nurseries. Many conventional fungicides are effective in reducing or delaying symptom expression but some may confound visual detection of infected plants. We tested film-forming polymers (FFPs) and surfactants for their ability to reduce infection and sporulation of P. ramorum on rhododendron. FFPs (Anti-Stress, Moisturin, Nature Shield, Nu-Film, and Vapor Gard) and surfactants (Tergitol, Zonix, and an unregistered AGAE product) were screened in detached-leaf assays. Anti-Stress, Nu-Film, Zonix, and a Nu-Film-Zonix mixture were additionally tested for durability, protection against exposure to infested water, and a reduction in sporulation. FFP effectiveness was retained for at least 3 weeks of exposure to overhead irrigation and rain. Relative to controls, foliar treatments protected rhododendron branches exposed to infested water. No treatments prevented symptom development when applied postinfection but leaves treated with Anti-Stress, Zonix, and the Nu-Film-Zonix mixture produced significantly fewer sporangia relative to controls. Application of FFPs and surfactants to quarantined, potentially infected plants offers a management tool for reducing infection and sporulation but not symptom expression, thereby limiting disease spread without interfering with disease detection.
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Fungicidas Industriales , Phytophthora , Polímeros , Rhododendron , Tensoactivos , Fungicidas Industriales/química , Fungicidas Industriales/farmacología , Phytophthora/fisiología , Polímeros/química , Polímeros/farmacología , Rhododendron/microbiología , Tensoactivos/química , Tensoactivos/farmacologíaRESUMEN
Invasive nonindigenous species are defined by their impacts: they substantially change native communities or ecosystems. Accordingly, invasive species might transform their habitats in ways that eventually become unfavorable to them, causing population declines or even extirpations. Here we use over 40 yr of systematically collected data on the abundance of the invasive rusty crayfish Faxonius rusticus from 17 lakes in northern Wisconsin, USA to explore whether population declines of this invader are related to the prevalence of rocky habitat, which shelters crayfish from predators and is unchanged by crayfish. We predicted that lakes with rock-dominated substrates would be resistant to F. rusticus population declines, whereas lakes lacking rock-dominated substrates would experience F. rusticus declines due to crayfish destruction of shelter-providing macrophytes. We found that in nearly one-half (47%) of the study lakes, F. rusticus experienced population declines over the study time period, and these lakes had significantly lower proportions of rock substrate than lakes that did not experience population declines. We recommend that more studies should investigate the potential for invasive species-mediated community or ecosystem feedbacks to eventually contribute to their own population declines.
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Astacoidea , Ecosistema , Animales , Especies Introducidas , Lagos , WisconsinRESUMEN
Our study evaluates the distribution, habitat associations, and current conservation status of the Snake River pilose crayfish Pacifastacus connectens (Faxon, 1914) and pilose crayfish Pacifastacus gambelii (Girard, 1852), two little-studied and data-deficient species endemic to the western United States. We first developed a species distribution model (SDM) for the pilose crayfishes based on their historical occurrence records using boosted regression trees and freshwater GIS data layers. We then sampled 163 sites in the summers of 2016 and 2017 within the distribution of these crayfishes, including 50 where these species were observed historically. We next compared our field results to modeled predictions of suitable habitat from the SDM. Our SDM predicted 73 sites (45%) we sampled as suitable for the pilose crayfishes, with a moderate AUC value of 0.824. The pilose crayfishes were generally predicted to occur in larger streams and rivers with less extreme upstream temperature and precipitation seasonality. We found the pilose crayfishes at only 20 (12%) of the 163 total sites we sampled, 14 (20%) of the 73 sites predicted as suitable for them by our SDM, and 12 (24%) of 50 historical sites that we sampled. We found the invasive virile crayfish Faxonius virilis (Hagen, 1870) at 22 sites total and 12 (24%) historical sites for the pilose crayfishes, and we found the "native invader" signal crayfish Pacifastacus leniusculus (Dana, 1852) at 29 sites total and 6 (12%) historical sites for the pilose crayfishes. We subsequently used a single classification tree to identify factors associated with our high rate of false positives for contemporary pilose crayfish distributions relative to our SDM. This classification tree identified the presence of invasive crayfishes, impairment of the benthic community, and sampling method as some of the factors differentiating false positives relative to true positives for the pilose crayfishes. Our study identified the historical distribution and habitat associations for P. connectens and P. gambelii using an SDM and contrasted this prediction to results of contemporary field sampling. We found that the pilose crayfishes have seemingly experienced substantial range declines, attributable to apparent displacement by invasive crayfishes and impairment or change to stream communities and habitat. We recommend increased conservation and management attention to P. connectens and P. gambelii in response to these findings.
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OBJECTIVES: Obstructive sleep apnea (OSA) is associated with cognitive impairment but the relationships between specific biomarkers and neurocognitive domains remain unclear. The present study examined the influence of common health comorbidities on these relationships. Adults with suspected OSA (N=60; 53% male; M age=52 years; SD=14) underwent neuropsychological evaluation before baseline polysomnography (PSG). Apneic syndrome severity, hypoxic strain, and sleep architecture disturbance were assessed through PSG. METHODS: Depression (Center for Epidemiological Studies Depression Scale, CESD), pain, and medical comorbidity (Charlson Comorbidity Index) were measured via questionnaires. Processing speed, attention, vigilance, memory, executive functioning, and motor dexterity were evaluated with cognitive testing. A winnowing approach identified 9 potential moderation models comprised of a correlated PSG variable, comorbid health factor, and cognitive performance. RESULTS: Regression analyses identified one significant moderation model: average blood oxygen saturation (AVO2) and depression predicting recall memory, accounting for 31% of the performance variance, p<.001. Depression was a significant predictor of recall memory, p<.001, but AVO2 was not a significant predictor. The interaction between depression and AVO2 was significant, accounting for an additional 10% of the variance, p<.001. The relationship between low AVO2 and low recall memory performance emerged when depression severity ratings approached a previously established clinical cutoff score (CESD=16). CONCLUSIONS: This study examined sleep biomarkers with specific neurocognitive functions among individuals with suspected OSA. Findings revealed that depression burden uniquely influence this pathophysiological relationship, which may aid clinical management. (JINS, 2018, 28, 864-875).
Asunto(s)
Cognición , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/psicología , Sueño , Adulto , Anciano , Nivel de Alerta , Atención , Biomarcadores , Disfunción Cognitiva , Comorbilidad , Depresión/complicaciones , Depresión/psicología , Función Ejecutiva , Femenino , Humanos , Masculino , Recuerdo Mental , Persona de Mediana Edad , Pruebas Neuropsicológicas , Oxígeno/sangre , Polisomnografía , Desempeño Psicomotor , Tiempo de Reacción , Adulto JovenRESUMEN
Purpose Patients with advanced cancer (ACPs) participating in phase I clinical trials inadequately understand many elements of informed consent (IC); however, the prevalence and impact of cognitive impairment has not been described. Patients and Methods ACPs enrolled onto phase I trials underwent neuropsychological assessment to evaluate cognitive functioning (CF) covering the following domains: memory (Hopkins Verbal Learning Test), executive functioning (Trail Making Test B), language (Boston Naming Test-Short Version and Controlled Oral Word Association Test), attention (Trail Making Test A and Wechsler Adult Intelligenence Scale-IV Digit Span), comprehension (Wechsler Adult Intelligence Scale-IV), and quality of life (Functional Assessment of Cancer Therapy-Cognitive Function). Structured interviews evaluated IC and decisional capacity. Psychological measures included distress (Hospital Anxiety Depression Scale) and depression (Beck Depression Inventory-II). Results One hundred eighteen ACPs on phase I trials were evaluated, with CF ranging from mild impairment to superior performance. Only 45% of ACPs recalled physician disclosure of the phase I trial purpose. The 50% of ACPs who correctly identified the phase I research purpose had greater CF compared with ACPs who did not, as revealed by the mean T scores for memory (37.2 ± 5.6 v 32.5 ± 5.1, respectively; P = .001), attention (29 ± 2.7 v 26.9 ± 2.4, respectively; P < .001), visual attention (35.2 ± 6.6 v 31.5 ± 6.2, respectively; P = .001), and executive function (38.9 ± 7.5 v 34 ± 7.1, respectively; P < .001). Older ACPs (≥ 60 years) were less likely to recall physician disclosure of phase I purpose than younger ACPs (30% v 70%, respectively; P = .02) and had measurable deficits in total memory (34.2 ± 5.0 v 37.3 ± 5.6, respectively; P = .002), attention (24.5 ± 2.6 v 28 ± 2.8, respectively; P < .001), and executive function (32.8 ± 7.3 v 36.4 ± 7.6, respectively; P = .01). Older ACPs, compared with younger ACPs, also had greater depression scores (10.6 ± 9.2 v 8.1 ± 5.2, respectively; P = .03) and lower quality-of-life scores (152 ± 29.6 v 167 ± 20, respectively; P = .03). After adjustment by age, no psychological or neuropsychological variable was further significantly associated with likelihood of purpose identification. Conclusion CF seems to play a role in ACP recall and comprehension of IC for early-phase clinical trials, especially among older ACPs.