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Crassulacean acid metabolism (CAM) is a highly plastic photosynthetic pathway with ecological and evolutionary significance, ranging from weak inducible to strong obligate forms. While most Crassulaceae taxa may be capable of performing CAM, the Macaronesian genus Aichryson has not traditionally been associated with CAM. We integrate phylogenetic, physiological, isotopic, anatomical and bioclimatic data to investigate the distribution, plasticity and evolutionary history of CAM and related traits in Aichryson. Our study includes all 15 accepted species, combining over 1100 occurrence records, carbon isotope (δ13C) data, nocturnal acid titration and a CAM performance experiment under temperature and drought gradients. Multivariate analyses of bioclimatic variables show clear ecological differentiation among the Azores, Madeira and Canary Islands, with life form strongly associated with climatic niche. Annual species are generally restricted to cooler, wetter climates, while the perennial A. tortuosum lineage, endemic to the arid eastern Canaries, exhibits increased succulence, lower minimum leaf conductance and higher CAM performance. Ancestral state reconstruction of δ13C data suggests that the ancestor of Aichryson possessed a predominantly C3 physiology with low‐level CAM capacity, from which independent shifts towards stronger CAM expression or reversions to predominant C3 photosynthesis occurred in response to local climatic conditions. Our CAM performance experiment revealed pronounced interspecific differences in nocturnal acid accumulation and plasticity. Some annuals, such as A. bollei, exhibited high CAM inducibility under stress, while others, like A. dumosum, maintained low ΔH+ across treatments, likely reflecting relaxed selection in mesic habitats. These physiological traits align with environmental niche and life history, supporting two main strategies: fast‐growing annuals with flexible CAM and slow‐growing perennials with more constitutive CAM and investment in leaf longevity, cuticular properties and water storage. These findings support a ‘CAM continuum’ and highlight the roles of ecological differentiation and climatic filtering in shaping CAM evolution. Aichryson emerges as a model system for understanding CAM plasticity and the interplay between photosynthetic pathways, life history and insular biogeography. We explore evolutionary changes in Crassulacean acid metabolism (CAM) and associated traits during the diversification of Aichryson (Crassulaceae) across the Macaronesian Islands. By combining field data, physiological measurements and phylogenetic analysis, we identify shifts in photosynthetic strategy linked to habitat transitions. Our findings highlight the role of CAM evolution in island adaptation and lineage diversification.

Adaptive radiation is a significant driver of biodiversity. Primarily studied in animal systems, mechanisms that trigger adaptive radiations remain poorly understood in plants. A frequently claimed indicator of adaptive radiation in plants is growth form diversity when tied to the occupation of different habitats. However, it remains obscure whether morphological adaptations manifest as growth form diversity per se or as its constituent traits. We use the classic Aeonium radiation from the Canary Islands to ask whether adaptation across climatic space is structured by growth form evolution. Using morphological sampling with site-associated climate in a phylogenetic context, we find that growth forms dictate adaptations to the local environment. Furthermore, we demonstrate that the response of specific traits to analogous environments is antagonistic when growth forms are different. This finding suggests for the first time that growth forms represent particular ecological functions, allowing the co-occurrence of closely related species, being a product of divergent selection during evolution in sympatry.

Globular somatic embryos can be induced from immature cotyledons of soybean (Glycine max L. Merr. cv Jack) placed on high levels of the auxin 2,4-dichlorophenoxyacetic acid (2,4-D). Somatic embryos develop from the adaxial side of the cotyledon, whereas the abaxial side evolves into a callus. Using a 9,280-cDNA clone array, we have compared steady-state RNA from the adaxial side from which embryos develop and from the abaxial callus at five time points over the course of the 4 weeks necessary for the development of globular embryos. In a second set of experiments, we have profiled the expression of each clone in the adaxial side during the same period. A total of 495 genes differentially expressed in at least one of these experiments were grouped according to the similarity of their expression profiles using a nonhierarchical clustering algorithm. Our results indicate that the appearance of somatic embryos is preceded by dedifferentiation of the cotyledon during the first 2 weeks on auxin. Changes in mRNA abundance of genes characteristic of oxidative stress and genes indicative of cell division in the adaxial side of the cotyledons suggest that the arrangement of the new cells into organized structures might depend on a genetically controlled balance between cell proliferation and cell death. Our data also suggest that the formation of somatic globular embryos is accompanied by the transcription of storage proteins and the synthesis of gibberellic acid.

Soybean [Glycine max (L.) Merrill] somatic embryos of the cultivar Jack underwent histodifferentiation in liquid Murashige and Skoog (MS) medium with 3% maltose, or according to the standard published procedure employing solidified MS media, permitting the recovery of an average of 8.1 and 3.9 embryos/mg of embryogenic tissue, respectively. Cotyledon-stage embryos that developed in liquid medium were ready for desiccation within 4 weeks, while the embryos from the standard procedure required a maturation step for an additional 4 weeks. Comparison of embryo development in MS medium with maltose or FN Lite-based medium without growth regulators and supplemented with maltose or an equimolar amount of sucrose revealed that sucrose promotes faster embryo histodifferentiation and maturation, and allows the recovery of up to 50% more mature, cotyledon-stage embryos within 3 weeks. The use of this liquid-medium-based protocol relative to the standard procedure led to a fourfold increase in the number of cotyledon-stage embryos recovered from other genotypes tested. In many cases, however, the percent germination was lower. Application of this new procedure also made it possible to harvest transgenic seed 9 months following biolistic bombardment, as compared to the 13 months required when the standard solid-medium-based protocol was used.

Spacecraft have been exploring the celestial bodies of our solar system for more than half a century. Despite the distances they have crossed, spacecraft remain in great part tethered to Earth for navigation and control purposes. As humankind continues to explore the solar system, the need for autonomous operations with minimal ground contact grows. The communication delays can be much larger than the required spacecraft response time such as during an orbit insertion maneuver or during entry decent and landing phase. Additionally, enhancing autonomy in navigation will continue to lighten the load on mission operations. When possible, performing navigation functions onboard circumvents light-time and human related delays, reduces the load on ground stations, and enables certain mission designs that are intractable without on-board decision-making. Optical Navigation in astrodynamics refers to the use of images taken by an onboard camera in order to determine the spacecraft's position. The images contain solar system bodies and therefore provide relative position, velocity and attitude information. The work in this dissertation focuses on the guidance, navigation, and control algorithms that allow for probes to travel the solar system. It revolves primarily around the autonomous navigation capabilities that optical navigation provides. By directly using the local environment, optical measurements can aid in spacecraft orientation and orbit determination and guidance, as well as science. The work in this thesis presents advances in heading determination filters, robust orbit determination methods using space imagery, fault detection cases, and machine learning for astrodynamics. The research is enabled by the initial development of an open-source software package, and presents research interests on its own. Applications of this thesis include mission design, Monte-Carlo analysis, and spacecraft autonomy.

The National Center for Biotechnology Information (NCBI) Reference Sequence (RefSeq) project provides several resources to support the animal genetics research community. Here, an abstract of an article by Pruitt et al providing RefSeq genome annotation for over 56 bird genomes and 90 mammalian genomes, including the alpaca, cattle, camel, goat, horse, pig, sheep, and water buffalo genomes is presented.

The National Center for Biotechnology Information (NCBI) Eukaryotic Genome Annotation Pipeline (available at www.ncbi.nlm.nih.gov/genouie/annotation_enk/, verified 26 May 2016) has been used to annotate over 280 organisms, including many animals of agricultural importance. The pipeline provides content for various NCBI resources, including Reference Sequence (RefSeq) sequence databases, Gene. BLAST databases, and the Map Viewer genome browser. The pipeline uses a modular framework for the automated execution of all annotation tasks from the fetching of raw and curated data from public repositories to the submission of the RefSeq-accessioned annotation products to public databases. The quality of the annotation is highly dependent on the availability of evidence for the species or closely related species. Alignments of RNA-Seq. traditional transcripts, expressed sequence tags, transcript assemblies, and proteins by Splign and ProSplign all contribute to the prediction of gene models by Gnomon, an alignment- and Hidden Markov Model-based gene prediction program developed at NCBI. The RefSeq group curates genes and transcripts for several plant and animal genomes, including pig. horse, and cattle. When available for the annotated species, the curated transcripts are aligned to the genome and take precedence over similar models produced by Gnomon based on other (noncurated) evidence. High-quality annotation is also achieved by producing models that compensate for assembly issues using the aligning evidence. The final annotation product can include transcripts and proteins for which the sequence has been modified relative to the draft genome assembly to correct a truncating mismatch or frameshift. or to fully represent a gene only partially present in the genome owing to sequence gaps. The final products of the pipeline include the annotated genomic sequences, the genes, and the transcript and protein products named based on orthology to model organisms or Blast hits to SwissProt/UniProtKb. We aim to reannotate organisms we maintain eveiy 2 yr. so that the annotation incorporates recent evidence deposited in public databases, and benefits from improvements in software. We produce a summary report with each annotation, containing the evidence on which the annotation is based, and statistics on the annotated products, hi the case of a reannotation. we also provide details about the genes and transcripts that changed. See all NCBI-annotated eukaryotes at >http://www.ncbi.nhn.nih.gov/genome/annotation_euk/all/ (verified 28 May 2016).