Hyperspectral Imaging With Machine Learning to Differentiate Cultivars, Growth Stages, Flowers, and Leaves of Industrial Hemp (Cannabis sativa L.).

As an emerging cash crop, industrial hemp (Cannabis sativa L.) grown for cannabidiol (CBD) has spurred a surge of interest in the United States. Cultivar selection and harvest timing are important to produce CBD hemp profitably and avoid economic loss resulting from the tetrahydrocannabinol (THC) concentration in the crop exceeding regulatory limits. Hence there is a need for differentiating CBD hemp cultivars and growth stages to aid in cultivar and genotype selection and optimization of harvest timing. Current methods that rely on visual assessment of plant phenotypes and chemical procedures are limited because of its subjective and destructive nature. In this study, hyperspectral imaging was proposed as a novel, objective, and non-destructive method for differentiating hemp cultivars, growth stages as well as plant organs (leaves and flowers). Five cultivars of CBD hemp were grown greenhouse conditions and leaves and flowers were sampled at five growth stages 2-10 weeks in 2-week intervals after flower initiation and scanned by a benchtop hyperspectral imaging system in the spectral range of 400-1000 nm. The acquired images were subjected to image processing procedures to extract the spectra of hemp samples. The spectral profiles and scatter plots of principal component analysis of the spectral data revealed a certain degree of separation between hemp cultivars, growth stages, and plant organs. Machine learning based on regularized linear discriminant analysis achieved the accuracy of up to 99.6% in differentiating the five hemp cultivars. Plant organ and growth stage need to be factored into model development for hemp cultivar classification. The classification models achieved 100% accuracy in differentiating the five growth stages and two plant organs. This study demonstrates the effectiveness of hyperspectral imaging for differentiating cultivars, growth stages and plant organs of CBD hemp, which is a potentially useful tool for growers and breeders of CBD hemp.

Cultural characterization and chlamydospore function of the Ganodermataceae present in the eastern United States.

The cultural characteristics of fungi can provide useful information for studying the biology and ecology of a group of closely related species, but these features are often overlooked in the order Polyporales. Optimal temperature and growth rate data can also be of utility for strain selection of cultivated fungi such as reishi (i.e., laccate Ganoderma species) and potential novel management tactics (e.g., solarization) for butt rot diseases caused by Ganoderma species. Historically, the taxonomy of the laccate (shiny) Ganoderma species has been unresolved and many species have been treated together as G. lucidum. The cultural characteristics of Ganoderma species from the United States are needed to understand the biology of these unique species that have all been lumped under this name. Culture morphology, average growth rate, optimal temperatures, and resiliency to elevated temperature exposure were characterized for isolates of Ganodermataceae taxa from the eastern United States, including Ganoderma curtisii, G. martinicense, G. meredithiae, G. ravenelii, G. sessile, G. tsugae, G. tuberculosum, G. cf. weberianum, G. zonatum, and Tomophagus colossus. We documented differences in linear growth rates and optimal temperatures between taxa. Isolates of G. sessile and T. colossus grew the fastest, and isolates of G. meredithiae, G. ravenelii, and G. tsugae grew the slowest. Isolates of G. sessile, G. martinicense, G. cf. weberianum, and T. colossus constitutively produced chlamydospores on malt extract agar, and these species were the only species to survive long-term exposure (30 or 40 d) to 40 C. We hypothesize that chlamydospores function as survival structures that serve as propagules resilient to adverse temperature conditions, especially heat. Cultural characteristics of G. martinicense, G. ravenelii, G. tuberculosum, and G. cf. weberianum collected from the United States are described for the first time.

Analyzing Patterns in NewSTEPs Site Review Recommendations: Practical Applications for Newborn Screening Programs.

The Newborn Screening Technical assistance and Evaluation Program (NewSTEPs) conducts non-regulatory site reviews of state newborn screening programs in the US with the goal of providing comprehensive reports and recommendations to support quality improvements within the system. A detailed coding and qualitative analysis of data extracted from reports of seven programs visited between 2012 and 2017, of thirteen pre-site visit surveys completed by state newborn screening programs, and of information from interviews conducted with three site review experts revealed four common themes that exist across states within the national newborn screening system. These themes include opportunities to implement improvements in: (1) communications inside and outside of the state newborn screening program, (2) education, (3) information technology, and (4) operations. The cross-cutting recommendations provided by NewSTEPs within the comprehensive site review reports may prove valuable for all state programs to consider and to incorporate as quality improvement measures in the absence of a full site review. The analysis of the site review process and recommendations identified important opportunities for improvement, many of which were previously unknown to be common across programs, and also provided affirmation of known challenges.

Pathogenicity of Ganoderma Species on Landscape Trees in the Southeastern United States.

The genus Ganoderma contains species that are associated with dead and declining host trees. Many species have been described as pathogens in literature, because anecdotally, the presence of fruiting bodies on living trees has been widely associated with a general decline in tree health. Few studies have investigated the pathogenicity of Ganoderma species on landscape trees in the southeastern U.S. Pathogenicity tests were used to determine the pathogenicity of G. curtisii, G. meredithiae, G. sessile, and G. zonatum on young, healthy landscape trees (Pinus elliottii var. elliottii, P. taeda, Quercus shumardii, Q. virginiana, and Butia odorata) common to the southeastern U.S. Inoculations were made by drilling into the sapwood of the lower bole and inserting wooden dowels that were infested with each Ganoderma species. In two field experiments, 11 to 12 months post inoculation, trees had no visual, external symptoms of disease. There were differences in the extent of internal xylem discoloration near the site of inoculation in comparison with the mock-inoculated control in experiment 1, but there were no differences relative to the control in experiment 2. In both experiments, G. sessile was the only species that was successfully reisolated from the pine and oak hosts. Although disease symptoms were not obvious, the reisolation of G. sessile outside the inoculation point was a significant finding, and suggests that this species was capable of infecting healthy sapwood. G. sessile constitutively produces chlamydospores within its vegetative mycelium, which may contribute to its persistence in the discolored sapwood. These data suggest that the Ganoderma species tested, following trunk wounding, are not pathogens of young, actively growing landscape trees that only possess sapwood. The establishment of these fungi using alternative infection courts (e.g., roots) and their interactions in older living trees (e.g., trees with heartwood) needs investigation to better understand their effects on tree health.

Cosmology and fundamental physics with the Euclid satellite.

Euclid is a European Space Agency medium-class mission selected for launch in 2020 within the cosmic vision 2015-2025 program. The main goal of Euclid is to understand the origin of the accelerated expansion of the universe. Euclid will explore the expansion history of the universe and the evolution of cosmic structures by measuring shapes and red-shifts of galaxies as well as the distribution of clusters of galaxies over a large fraction of the sky. Although the main driver for Euclid is the nature of dark energy, Euclid science covers a vast range of topics, from cosmology to galaxy evolution to planetary research. In this review we focus on cosmology and fundamental physics, with a strong emphasis on science beyond the current standard models. We discuss five broad topics: dark energy and modified gravity, dark matter, initial conditions, basic assumptions and questions of methodology in the data analysis. This review has been planned and carried out within Euclid's Theory Working Group and is meant to provide a guide to the scientific themes that will underlie the activity of the group during the preparation of the Euclid mission.

Elucidating wood decomposition by four species of Ganoderma from the United States.

The laccate (shiny or varnished) Ganoderma contain fungi that are important wood decay fungi of living trees and decomposers of woody debris. They are also an important group of fungi for their degradative enzymes and bioprocessing potential. Laboratory decay microcosms (LDMs) were used to study the relative decay ability of G anoderma curtisii, Ganoderma meredithiae, Ganoderma sessile, and G anoderma zonatum, which are four commonly encountered Ganoderma species in the U.S., across four wood types (Pinus taeda, Quercus nigra, Q uercus virginiana, and Sabal palmetto). Generally, all Ganoderma species were able to decay all types of wood tested despite not being associated with only certain wood types in nature. G. sessile, on average caused the most decay across all wood types. Among the wood types tested, water oak (Q. nigra) had the most mass loss by all species of Ganoderma. Scanning electron microscopy was used to assess micromorphological decay patterns across all treatments. All Ganoderma species simultaneously decayed wood cells of all wood types demonstrating their ability to attack all cell wall components. However, G. zonatum caused selective delignification in some sclerenchyma fibers of the vascular bundles in palm (S. palmetto) as well as in fibers of water oak. In addition, G. zonatum hyphae penetrated fibers of palm and oak wood causing an unusual decay not often observed in basidiomycetes resulting in cavity formation in secondary walls. Cavities within the secondary walls of fibers gradually expanded and coalesced resulting in degradation of the S2 layer. Differences in colony growth rates were observed when Ganoderma species were grown on medium amended with water soluble sapwood extracts from each wood type. G. meredithiae had enhanced growth on all media amended with sapwood extracts, while G. curtisii, G. sessile and G. zonatum had slower growth on loblolly pine extract amended medium.

New constraints on the early expansion history of the universe.

Cosmic microwave background measurements have pushed to higher resolution, lower noise, and more sky coverage. These data enable a unique test of the early Universe's expansion rate and constituents such as effective number of relativistic degrees of freedom and dark energy. Using the most recent data from Planck and WMAP9, we constrain the expansion history in a model-independent manner from today back to redshift z=10(5). The Hubble parameter is mapped to a few percent precision, limiting early dark energy and extra relativistic degrees of freedom within a model-independent approach to 2%-16% and 0.71 equivalent neutrino species, respectively (95% C.L.). Within dark radiation, barotropic ether, and Doran-Robbers models, the early dark energy constraints are 3.3%, 1.9%, and 1.2%, respectively.

Model-independent tests of cosmic gravity.

Gravitation governs the expansion and fate of the universe, and the growth of large-scale structure within it, but has not been tested in detail on these cosmic scales. The observed acceleration of the expansion may provide signs of gravitational laws beyond general relativity (GR). Since the form of any such extension is not clear, from either theory or data, we adopt a model-independent approach to parametrizing deviations to the Einstein framework. We explore the phase space dynamics of two key post-GR functions and derive a classification scheme, and an absolute criterion on accuracy necessary for distinguishing classes of gravity models. Future surveys will be able to constrain the post-GR functions' amplitudes and forms to the required precision, and hence reveal new aspects of gravitation.

Limits of quintessence.

We present evidence that the simplest particle-physics scalar-field models of dynamical dark energy can be separated into distinct behaviors based on the acceleration or deceleration of the field as it evolves down its potential towards a zero minimum. We show that these models occupy narrow regions in the phase plane of w and w', the dark energy equation of state and its time derivative in units of the Hubble time. Restricting an energy scale of the dark energy microphysics limits how closely a scalar field can resemble a cosmological constant. These results, indicating a desired measurement resolution of order sigma(w') approximately = (1+w), define firm targets for observational tests of the physics of dark energy.

Exploring the expansion history of the universe.

Exploring the recent expansion history of the universe promises insights into the cosmological model, the nature of dark energy, and potentially clues to high energy physics theories and gravitation. We examine the extent to which precision distance-redshift observations can map out the history, including the acceleration-deceleration transition, and the components and equations of state of the energy density. We consider the ability to distinguish between various dynamical scalar field models for the dark energy, as well as higher dimension and alternate gravity theories. Finally, we present a new, advantageous parametrization for the study of dark energy.