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Introduction: Postgraduate fellowships are growing in midwifery and yet are poorly understood by the profession. These fellowships are optional for midwives interested in developing advanced skills, transitioning to specialty practice, or entering or re-entering professional practice. The purpose of this study was to explore the characteristics and outcomes of US postgraduate midwifery fellowships as described by midwifery fellowship program directors., Methods: Postgraduate midwifery fellowship programs in the United States were identified through an environmental scan and snowball sampling. Directors of these fellowship programs were invited to complete a survey and an open-ended interview to determine their program's characteristics and outcomes. Quantitative data were summarized, and thematic analysis was used to explore the qualitative data., Results: An environmental scan and snowball sampling identified 17 postgraduate midwifery fellowship programs. Thirteen fellowship program directors completed a survey (76.5%), and 11 completed an interview (64.7%). The findings identified program characteristics, including location, structure, funding, and educational offerings, of midwifery fellowship programs. The thematic analysis revealed the emergence of 3 themes highlighting the creation of support for midwives in transition, including new graduates and practicing midwives returning to practice after a hiatus or shifting to specialty practice: (1) stepping stones, (2) empowered and equipped, and (3) innovative future. Community birth practice was defined as specialty practice by these directors., Discussion: The results of this study inform the profession of the availability of fellowships and the development of future high-quality midwifery fellowships. Postgraduate midwifery fellowships should not be required for entry to practice but have a place in the work-study opportunities available to US midwives., (© 2024 by the American College of Nurse‐Midwives.)

We present chromosome-level genome assemblies from representative species of three independently evolved seagrass lineages: Posidonia oceanica, Cymodocea nodosa, Thalassia testudinum and Zostera marina. We also include a draft genome of Potamogeton acutifolius, belonging to a freshwater sister lineage to Zosteraceae. All seagrass species share an ancient whole-genome triplication, while additional whole-genome duplications were uncovered for C. nodosa, Z. marina and P. acutifolius. Comparative analysis of selected gene families suggests that the transition from submerged-freshwater to submerged-marine environments mainly involved fine-tuning of multiple processes (such as osmoregulation, salinity, light capture, carbon acquisition and temperature) that all had to happen in parallel, probably explaining why adaptation to a marine lifestyle has been exceedingly rare. Major gene losses related to stomata, volatiles, defence and lignification are probably a consequence of the return to the sea rather than the cause of it. These new genomes will accelerate functional studies and solutions, as continuing losses of the 'savannahs of the sea' are of major concern in times of climate change and loss of biodiversity., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Currents are unique drivers of oceanic phylogeography and thus determine the distribution of marine coastal species, along with past glaciations and sea-level changes. Here we reconstruct the worldwide colonization history of eelgrass (Zostera marina L.), the most widely distributed marine flowering plant or seagrass from its origin in the Northwest Pacific, based on nuclear and chloroplast genomes. We identified two divergent Pacific clades with evidence for admixture along the East Pacific coast. Two west-to-east (trans-Pacific) colonization events support the key role of the North Pacific Current. Time-calibrated nuclear and chloroplast phylogenies yielded concordant estimates of the arrival of Z. marina in the Atlantic through the Canadian Arctic, suggesting that eelgrass-based ecosystems, hotspots of biodiversity and carbon sequestration, have only been present there for ~243 ky (thousand years). Mediterranean populations were founded ~44 kya, while extant distributions along western and eastern Atlantic shores were founded at the end of the Last Glacial Maximum (~19 kya), with at least one major refuge being the North Carolina region. The recent colonization and five- to sevenfold lower genomic diversity of the Atlantic compared to the Pacific populations raises concern and opportunity about how Atlantic eelgrass might respond to rapidly warming coastal oceans., (© 2023. The Author(s).)

Distribution of Earth's biomes is structured by the match between climate and plant traits, which in turn shape associated communities and ecosystem processes and services. However, that climate-trait match can be disrupted by historical events, with lasting ecosystem impacts. As Earth's environment changes faster than at any time in human history, critical questions are whether and how organismal traits and ecosystems can adjust to altered conditions. We quantified the relative importance of current environmental forcing versus evolutionary history in shaping the growth form (stature and biomass) and associated community of eelgrass ( Zostera marina ), a widespread foundation plant of marine ecosystems along Northern Hemisphere coastlines, which experienced major shifts in distribution and genetic composition during the Pleistocene. We found that eelgrass stature and biomass retain a legacy of the Pleistocene colonization of the Atlantic from the ancestral Pacific range and of more recent within-basin bottlenecks and genetic differentiation. This evolutionary legacy in turn influences the biomass of associated algae and invertebrates that fuel coastal food webs, with effects comparable to or stronger than effects of current environmental forcing. Such historical lags in phenotypic acclimatization may constrain ecosystem adjustments to rapid anthropogenic climate change, thus altering predictions about the future functioning of ecosystems.

While considerable evidence exists of biogeographic patterns in the intensity of species interactions, the influence of these patterns on variation in community structure is less clear. Studying how the distributions of traits in communities vary along global gradients can inform how variation in interactions and other factors contribute to the process of community assembly. Using a model selection approach on measures of trait dispersion in crustaceans associated with eelgrass ( Zostera marina ) spanning 30° of latitude in two oceans, we found that dispersion strongly increased with increasing predation and decreasing latitude. Ocean and epiphyte load appeared as secondary predictors; Pacific communities were more overdispersed while Atlantic communities were more clustered, and increasing epiphytes were associated with increased clustering. By examining how species interactions and environmental filters influence community structure across biogeographic regions, we demonstrate how both latitudinal variation in species interactions and historical contingency shape these responses. Community trait distributions have implications for ecosystem stability and functioning, and integrating large-scale observations of environmental filters, species interactions and traits can help us predict how communities may respond to environmental change.

Due to rising global surface temperatures, Arctic habitats are becoming thermally suitable for temperate species. Whether a temperate species can immigrate into an ice-free Arctic depends on its ability to tolerate extreme seasonal fluctuations in daylength. Thus, understanding adaptations to polar light conditions can improve the realism of models predicting poleward range expansions in response to climate change. Plant adaptations to polar light have rarely been studied and remain unknown in seagrasses. If these ecosystem engineers can migrate polewards, seagrasses will enrich biodiversity, and carbon capture potential in shallow coastal regions of the Arctic. Eelgrass ( Zostera marina ) is the most widely distributed seagrass in the northern hemisphere. As the only seagrass species growing as far north as 70°N, it is the most likely candidate to first immigrate into an ice-free Arctic. Here, we describe seasonal (and diurnal) changes in photosynthetic characteristics, and in genome-wide gene expression patterns under strong annual fluctuations of daylength. We compared PAM measurements and RNA-seq data between two populations at the longest and shortest day of the year: (1) a Mediterranean population exposed to moderate annual fluctuations of 10-14 h daylength and (2) an Arctic population exposed to high annual fluctuations of 0-24 h daylength. Most of the gene expression specificities of the Arctic population were found in functions of the organelles (chloroplast and mitochondrion). In winter, Arctic eelgrass conserves energy by repressing respiration and reducing photosynthetic energy fluxes. Although light-reactions, and genes involved in carbon capture and carbon storage were upregulated in summer, enzymes involved in CO 2 fixation and chlorophyll-synthesis were upregulated in winter, suggesting that winter metabolism relies not only on stored energy resources but also on active use of dim light conditions. Eelgrass is unable to use excessive amounts of light during summer and demonstrates a significant reduction in photosynthetic performance under long daylengths, possibly to prevent photoinhibition constrains. Our study identified key mechanisms that allow eelgrass to survive under Arctic light conditions and paves the way for experimental research to predict whether and up to which latitude eelgrass can potentially migrate polewards in response to climate change., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Jueterbock, Duarte, Coyer, Olsen, Kopp, Smolina, Arnaud-Haond, Hu and Hoarau.)

Background:  Seagrasses (Alismatales) are the only fully marine angiosperms.  Zostera marina  (eelgrass) plays a crucial role in the functioning of coastal marine ecosystems and global carbon sequestration. It is the most widely studied seagrass and has become a marine model system for exploring adaptation under rapid climate change. The original draft genome (v.1.0) of the seagrass  Z . marina  (L.) was based on a combination of Illumina mate-pair libraries and fosmid-ends. A total of 25.55 Gb of Illumina and 0.14 Gb of Sanger sequence was obtained representing 47.7× genomic coverage. The assembly resulted in ~2000 unordered scaffolds (L50 of 486 Kb), a final genome assembly size of 203MB, 20,450 protein coding genes and 63% TE content. Here, we present an upgraded chromosome-scale genome assembly and compare v.1.0 and the new v.3.1, reconfirming previous results from Olsen et al. (2016), as well as pointing out new findings.   Methods:  The same high molecular weight DNA used in the original sequencing of the Finnish clone was used. A high-quality reference genome was assembled with the MECAT assembly pipeline combining PacBio long-read sequencing and Hi-C scaffolding.  Results:  In total, 75.97 Gb PacBio data was produced. The final assembly comprises six pseudo-chromosomes and 304 unanchored scaffolds with a total length of 260.5Mb and an N50 of 34.6 MB, showing high contiguity and few gaps (~0.5%). 21,483 protein-encoding genes are annotated in this assembly, of which 20,665 (96.2%) obtained at least one functional assignment based on similarity to known proteins.  Conclusions:  As an important marine angiosperm, the improved  Z. marina  genome assembly will further assist evolutionary, ecological, and comparative genomics at the chromosome level. The new genome assembly will further our understanding into the structural and physiological adaptations from land to marine life., Competing Interests: No competing interests were disclosed., (Copyright: © 2021 Ma X et al.)

Evolutionary theory predicts that clonal organisms are more susceptible to extinction than sexually reproducing organisms, due to low genetic variation and slow rates of evolution. In agreement, conservation management considers genetic variation as the ultimate measure of a population's ability to survive over time. However, clonal plants are among the oldest living organisms on our planet. Here, we test the hypothesis that clonal seagrass meadows display epigenetic variation that complements genetic variation as a source of phenotypic variation. In a clonal meadow of the seagrass Zostera marina , we characterized DNA methylation among 42 shoots. We also sequenced the whole genome of 10 shoots to correlate methylation patterns with photosynthetic performance under exposure to and recovery from 27°C, while controlling for somatic mutations. Here, we show for the first time that clonal seagrass shoots display DNA methylation variation that is independent from underlying genetic variation, and associated with variation in photosynthetic performance under experimental conditions. It remains unknown to what degree this association could be influenced by epigenetic responses to transplantation-related stress, given that the methylomes showed a strong shift under acclimation to laboratory conditions. The lack of untreated control samples in the heat stress experiment did not allow us to distinguish methylome shifts induced by acclimation from such induced by heat stress. Notwithstanding, the co-variation in DNA methylation and photosynthetic performance may be linked via gene expression because methylation patterns varied in functionally relevant genes involved in photosynthesis, and in the repair and prevention of heat-induced protein damage. While genotypic diversity has been shown to enhance stress resilience in seagrass meadows, we suggest that epigenetic variation plays a similar role in meadows dominated by a single genotype. Consequently, conservation management of clonal plants should consider epigenetic variation as indicator of resilience and stability., (Copyright © 2020 Jueterbock, Boström, Coyer, Olsen, Kopp, Dhanasiri, Smolina, Arnaud-Haond, Van de Peer and Hoarau.)

The eelgrass Zostera marina is an important foundation species of coastal areas in the Northern Hemisphere, but is continuing to decline, despite management actions. The development of new management tools is therefore urgent in order to prioritize limited resources for protecting meadows most vulnerable to local extinctions and identifying most valuable present and historic meadows to protect and restore, respectively. We assessed 377 eelgrass meadows along the complex coastlines of two fjord regions on the Swedish west coast-one is currently healthy and the other is substantially degraded. Shoot dispersal for all meadows was assessed with Lagrangian biophysical modeling (scale: 100-1,000 m) and used for barrier analysis and clustering; a subset (n = 22) was also assessed with population genetic methods (20 microsatellites) including diversity, structure, and network connectivity. Both approaches were in very good agreement, resulting in seven subpopulation groupings or management units (MUs). The MUs correspond to a spatial scale appropriate for coastal management of "waterbodies" used in the European Water Framework Directive. Adding demographic modeling based on the genetic and biophysical data as a third approach, we are able to assess past, present, and future metapopulation dynamics to identify especially vulnerable and valuable meadows. In a further application, we show how the biophysical approach, using eigenvalue perturbation theory (EPT) and distribution records from the 1980s, can be used to identify lost meadows where restoration would best benefit the present metapopulation. The combination of methods, presented here as a toolbox, allows the assessment of different temporal and spatial scales at the same time, as well as ranking of specific meadows according to key genetic, demographic and ecological metrics. It could be applied to any species or region, and we exemplify its versatility as a management guide for eelgrass along the Swedish west coast., (© 2020 The Authors. Ecological Applications published by Wiley Periodicals, Inc. on behalf of Ecological Society of America.)

Background: The spatial distribution of genetic diversity and structure has important implications for conservation as it reveals a species' strong and weak points with regard to stability and evolutionary capacity. Temporal genetic stability is rarely tested in marine species other than commercially important fishes, but is crucial for the utility of temporal snapshots in conservation management. High and stable diversity can help to mitigate the predicted northward range shift of seaweeds under the impact of climate change. Given the key ecological role of fucoid seaweeds along rocky shores, the positive effect of genetic diversity may reach beyond the species level to stabilize the entire intertidal ecosystem along the temperate North Atlantic. In this study, we estimated the effective population size, as well as temporal changes in genetic structure and diversity of the seaweed F. serratus using 22 microsatellite markers. Samples were taken across latitudes and a range of temperature regimes at seven locations with decadal sampling (2000 and 2010)., Results: Across latitudes, genetic structure and diversity remained stable over 5-10 generations. Stable small-scale structure enhanced regional diversity throughout the species' range. In accordance with its biogeographic history, effective population size and diversity peaked in the species' mid-range in Brittany (France), and declined towards its leading and trailing edge to the north and south. At the species' southern edge, multi-locus-heterozygosity displayed a strong decline from 1999 to 2010., Conclusion: Temporally stable genetic structure over small spatial scales is a potential driver for local adaptation and species radiation in the genus Fucus. Survival and adaptation of the low-diversity leading edge of F. serratus may be enhanced by regional gene flow and 'surfing' of favorable mutations or impaired by the accumulation of deleterious mutations. Our results have clear implications for the conservation of F. serratus at its genetically unique southern edge in Northwest Iberia, where increasing temperatures are likely the major cause for the decline not only of F. serratus, but also other intertidal and subtidal macroalgae. We expect that F. serratus will disappear from Northwest Iberia by 2100 if genetic rescue is not induced by the influx of genetic variation from Brittany.

Maintaining and enabling evolutionary processes within meta-populations are critical to resistance, resilience and adaptive potential. Knowledge about which populations act as sources or sinks, and the direction of gene flow, can help to focus conservation efforts more effectively and forecast how populations might respond to future anthropogenic and environmental pressures. As a foundation species and habitat provider, Zostera marina (eelgrass) is of critical importance to ecosystem functions including fisheries. Here, we estimate connectivity of Z. marina in the Skagerrak-Kattegat region of the North Sea based on genetic and biophysical modelling. Genetic diversity, population structure and migration were analysed at 23 locations using 20 microsatellite loci and a suite of analytical approaches. Oceanographic connectivity was analysed using Lagrangian dispersal simulations based on contemporary and historical distribution data dating back to the late 19th century. Population clusters, barriers and networks of connectivity were found to be very similar based on either genetic or oceanographic analyses. A single-generation model of dispersal was not realistic, whereas multigeneration models that integrate stepping-stone dispersal and extant and historic distribution data were able to capture and model genetic connectivity patterns well. Passive rafting of flowering shoots along oceanographic currents is the main driver of gene flow at this spatial-temporal scale, and extant genetic connectivity strongly reflects the "ghost of dispersal past" sensu Benzie, 1999. The identification of distinct clusters, connectivity hotspots and areas where connectivity has become limited over the last century is critical information for spatial management, conservation and restoration of eelgrass.

Trauma care has traditionally focused on prehospital and hospital settings, yet many injured patients report emotional distress in the postacute care setting, which is known to impair recovery. The objective of this study was to assess postdischarge emotional recovery and communication preferences. An observational cohort of 100 adult patients from our Level 1 Trauma Center was surveyed one to two months postdischarge. Among those employed preinjury, 44 per cent had not returned to work. Nearly half screened positive for emotional issues (posttraumatic stress disorder, depression, and/or psychological distress); of these, only 35 per cent considered getting professional help and only 10 per cent received help. The barrier most cited (58%) was cost; 42 per cent did not know how or where to get help. Most participants responded "no" or "I don't know" when asked if they had received information about coping with negative emotions after injury and how to seek help from a doctor to address these emotions. Two-thirds preferred to receive such information via phone call from a health care provider or by text. Eighty-nine per cent owned a cellphone. Our trauma systems are failing to provide comprehensive care or look at the ultimate outcomes of our patients, yet modern technology could provide needed resources to patients in novel ways.

Marine-freshwater and freshwater-marine transitions have been key events in the evolution of life, and most major groups of organisms have independently undergone such events at least once in their history. Here, we first compile an inventory of bidirectional freshwater and marine transitions in multicellular photosynthetic eukaryotes. While green and red algae have mastered multiple transitions in both directions, brown algae have colonized freshwater on a maximum of six known occasions, and angiosperms have made the transition to marine environments only two or three times. Next, we review the early evolutionary events leading to the colonization of current habitats. It is commonly assumed that the conquest of land proceeded in a sequence from marine to freshwater habitats. However, recent evidence suggests that early photosynthetic eukaryotes may have arisen in subaerial or freshwater environments and only later colonized marine environments as hypersaline oceans were diluted to the contemporary level. Although this hypothesis remains speculative, it is important to keep these alternative scenarios in mind when interpreting the current habitat distribution of plants and algae. Finally, we discuss the roles of structural and functional adaptations of the cell wall, reactive oxygen species scavengers, osmoregulation, and reproduction. These are central for acclimatization to freshwater or to marine environments. We observe that successful transitions appear to have occurred more frequently in morphologically simple forms and conclude that, in addition to physiological studies of euryhaline species, comparative studies of closely related species fully adapted to one or the other environment are necessary to better understand the adaptive processes., (© 2017 Phycological Society of America.)

A novel nanoparticulate catalyst of copper (Cu) and ruthenium (Ru) was designed for low-temperature ammonia oxidation at near-stoichiometric mixtures using a bottom-up approach. A synergistic effect of the two metals was found. An optimum CuRu catalyst presents a reaction rate threefold higher than that for Ru and forty-fold higher than that for Cu. X-ray absorption spectroscopy suggests that in the most active catalyst Cu forms one or two monolayer thick patches on Ru and the catalysts are less active once 3D Cu islands form. The good performance of the tuned Cu/Ru catalyst is attributed to changes in the electronic structure, and thus the altered adsorption properties of the surface Cu sites., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Populations distributed across a broad thermal cline are instrumental in addressing adaptation to increasing temperatures under global warming. Using a space-for-time substitution design, we tested for parallel adaptation to warm temperatures along two independent thermal clines in Zostera marina, the most widely distributed seagrass in the temperate Northern Hemisphere. A North-South pair of populations was sampled along the European and North American coasts and exposed to a simulated heatwave in a common-garden mesocosm. Transcriptomic responses under control, heat stress and recovery were recorded in 99 RNAseq libraries with ~13 000 uniquely annotated, expressed genes. We corrected for phylogenetic differentiation among populations to discriminate neutral from adaptive differentiation. The two southern populations recovered faster from heat stress and showed parallel transcriptomic differentiation, as compared with northern populations. Among 2389 differentially expressed genes, 21 exceeded neutral expectations and were likely involved in parallel adaptation to warm temperatures. However, the strongest differentiation following phylogenetic correction was between the three Atlantic populations and the Mediterranean population with 128 of 4711 differentially expressed genes exceeding neutral expectations. Although adaptation to warm temperatures is expected to reduce sensitivity to heatwaves, the continued resistance of seagrass to further anthropogenic stresses may be impaired by heat-induced downregulation of genes related to photosynthesis, pathogen defence and stress tolerance., (© 2016 John Wiley & Sons Ltd.)

Seagrasses colonized the sea on at least three independent occasions to form the basis of one of the most productive and widespread coastal ecosystems on the planet. Here we report the genome of Zostera marina (L.), the first, to our knowledge, marine angiosperm to be fully sequenced. This reveals unique insights into the genomic losses and gains involved in achieving the structural and physiological adaptations required for its marine lifestyle, arguably the most severe habitat shift ever accomplished by flowering plants. Key angiosperm innovations that were lost include the entire repertoire of stomatal genes, genes involved in the synthesis of terpenoids and ethylene signalling, and genes for ultraviolet protection and phytochromes for far-red sensing. Seagrasses have also regained functions enabling them to adjust to full salinity. Their cell walls contain all of the polysaccharides typical of land plants, but also contain polyanionic, low-methylated pectins and sulfated galactans, a feature shared with the cell walls of all macroalgae and that is important for ion homoeostasis, nutrient uptake and O2/CO2 exchange through leaf epidermal cells. The Z. marina genome resource will markedly advance a wide range of functional ecological studies from adaptation of marine ecosystems under climate warming, to unravelling the mechanisms of osmoregulation under high salinities that may further inform our understanding of the evolution of salt tolerance in crop plants.

Nutrient pollution and reduced grazing each can stimulate algal blooms as shown by numerous experiments. But because experiments rarely incorporate natural variation in environmental factors and biodiversity, conditions determining the relative strength of bottom-up and top-down forcing remain unresolved. We factorially added nutrients and reduced grazing at 15 sites across the range of the marine foundation species eelgrass (Zostera marina) to quantify how top-down and bottom-up control interact with natural gradients in biodiversity and environmental forcing. Experiments confirmed modest top-down control of algae, whereas fertilisation had no general effect. Unexpectedly, grazer and algal biomass were better predicted by cross-site variation in grazer and eelgrass diversity than by global environmental gradients. Moreover, these large-scale patterns corresponded strikingly with prior small-scale experiments. Our results link global and local evidence that biodiversity and top-down control strongly influence functioning of threatened seagrass ecosystems, and suggest that biodiversity is comparably important to global change stressors., (© 2015 John Wiley & Sons Ltd/CNRS.)

Red blood cells (RBCs), responsible for oxygen delivery and carbon dioxide exchange, are essential for our well-being. Alternative RBC sources are needed to meet the increased demand for RBC transfusions projected to occur as our population ages. We previously have discovered that erythroblasts derived from the early mouse embryo can self-renew extensively ex vivo for many months. To better understand the mechanisms regulating extensive erythroid self-renewal, global gene expression data sets from self-renewing and differentiating erythroblasts were analyzed and revealed the differential expression of Bmi-1. Bmi-1 overexpression conferred extensive self-renewal capacity upon adult bone-marrow-derived self-renewing erythroblasts, which normally have limited proliferative potential. Importantly, Bmi-1 transduction did not interfere with the ability of extensively self-renewing erythroblasts (ESREs) to terminally mature either in vitro or in vivo. Bmi-1-induced ESREs can serve to generate in vitro models of erythroid-intrinsic disorders and ultimately may serve as a source of cultured RBCs for transfusion therapy., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

The seagrass Posidonia oceanica is a key engineering species structuring coastal marine systems throughout much of the Mediterranean basin. Its decline is of concern, leading to the search for short- and long-term indicators of seagrass health. Using ArcGIS maps from a recent, high-resolution (1-4 km) modelling study of 18 disturbance factors affecting coastal marine systems across the Mediterranean (Micheli et al. 2013, http://globalmarine.nceas.ucsb.edu/mediterranean/), we tested for correlations with genetic diversity metrics (allelic diversity, genotypic/clonal diversity and heterozygosity) in a meta-analysis of 56 meadows. Contrary to initial predictions, weak but significantly positive correlations were found for commercial shipping, organic pollution (pesticides) and cumulative impact. This counterintuitive finding suggests greater resistance and resilience of individuals with higher genetic and genotypic diversity under disturbance (at least for a time) and/or increased sexual reproduction under an intermediate disturbance model. We interpret the absence of low and medium levels of genetic variation at impacted locations as probable local extinctions of individuals that already exceeded their resistance capacity. Alternatively, high diversity at high-impact sites is likely a temporal artefact, reflecting the mismatch with pre-environmental impact conditions, especially because flowering and sexual recruitment are seldom observed. While genetic diversity metrics are a valuable tool for restoration and mitigation, caution must be exercised in the interpretation of correlative patterns as found in this study, because the exceptional longevity of individuals creates a temporal mismatch that may falsely suggest good meadow health status, while gradual deterioration of allelic diversity might go unnoticed., (© 2015 John Wiley & Sons Ltd.)

Hybrid zones provide an ideal natural experiment to study the selective forces driving evolution of reproductive barriers and speciation. If hybrid offspring are less fit than the parental species, pre-zygotic isolating barriers can evolve and strengthen in response to selection against the hybrids (reinforcement). Four contact zones between the intertidal macroalgae Fucus serratus (Fs) and Fucus distichus (Fd), characterized by varying times of sympatry and order of species introduction provide an opportunity to investigate reinforcement. We examined patterns of hybridization and reproductive isolation between Fs and Fd in: (i) northern Norway (consisting of two natural sites, 10 000 years old), (ii) the Kattegat near Denmark (Fd introduced, nineteenth century) and (iii) Iceland (Fs introduced, nineteenth century). Using 10 microsatellites and chloroplast DNA, we showed that hybridization and introgression decreased with increasing duration of sympatry. The two younger contact zones revealed 13 and 24% hybrids and several F 1 individuals, in contrast to the older contact zone with 2-3% hybrids and an absence of F 1s. Cross-fertilization experiments revealed that the reduction in hybridization in the oldest zone is consistent with increased gametic incompatibility.

Manta and devil rays are an iconic group of globally distributed pelagic filter feeders, yet their evolutionary history remains enigmatic. We employed next generation sequencing of mitogenomes for nine of the 11 recognized species and two outgroups; as well as additional Sanger sequencing of two mitochondrial and two nuclear genes in an extended taxon sampling set. Analysis of the mitogenome coding regions in a Maximum Likelihood and Bayesian framework provided a well-resolved phylogeny. The deepest divergences distinguished three clades with high support, one containing Manta birostris, Manta alfredi, Mobula tarapacana, Mobula japanica and Mobula mobular; one containing Mobula kuhlii, Mobula eregoodootenkee and Mobula thurstoni; and one containing Mobula munkiana, Mobula hypostoma and Mobula rochebrunei. Mobula remains paraphyletic with the inclusion of Manta, a result that is in agreement with previous studies based on molecular and morphological data. A fossil-calibrated Bayesian random local clock analysis suggests that mobulids diverged from Rhinoptera around 30 Mya. Subsequent divergences are characterized by long internodes followed by short bursts of speciation extending from an initial episode of divergence in the Early and Middle Miocene (19-17 Mya) to a second episode during the Pliocene and Pleistocene (3.6 Mya - recent). Estimates of divergence dates overlap significantly with periods of global warming, during which upwelling intensity - and related high primary productivity in upwelling regions - decreased markedly. These periods are hypothesized to have led to fragmentation and isolation of feeding regions leading to possible regional extinctions, as well as the promotion of allopatric speciation. The closely shared evolutionary history of mobulids in combination with ongoing threats from fisheries and climate change effects on upwelling and food supply, reinforces the case for greater protection of this charismatic family of pelagic filter feeders., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Genome-wide transcription analysis between related species occurring in overlapping ranges can provide insights into the molecular basis underlying different ecological niches. The co-occurring seagrass species, Zostera marina and Nanozostera noltii, are found in marine coastal environments throughout the northern hemisphere. Z. marina is often dominant in subtidal environments and subjected to fewer temperature extremes compared to the predominately intertidal and more stress-tolerant N. noltii. We exposed plants of both species to a realistic heat wave scenario in a common-stress-garden experiment. Using RNA-seq (~7million reads/library), four Z. marina and four N. noltii libraries were compared representing northern (Denmark) and southern (Italy) locations within the co-occurring range of the species' European distribution. A total of 8977 expressed genes were identified, of which 78 were directly related to heat stress. As predicted, both species were negatively affected by the heat wave, but showed markedly different molecular responses. In Z. marina the heat response was similar across locations in response to the heatwave at 26°C, with a complex response in functions related to protein folding, synthesis of ribosomal chloroplast proteins, proteins involved in cell wall modification and heat shock proteins (HSPs). In N. noltii the heat response markedly differed between locations, while HSP genes were not induced in either population. Our results suggest that as coastal seawater temperatures increase, Z. marina will disappear along its southern most ranges, whereas N. noltii will continue to move north. As a consequence, sub- and intertidal habitat partitioning may weaken in more northern regions because the higher thermal tolerance of N. noltii provides a competitive advantage in both habitats. Although previous studies have focused on HSPs, the present study clearly demonstrates that a broader examination of stress related genes is necessary., (Copyright © 2014. Published by Elsevier B.V.)

Seaweed-dominated communities are predicted to disappear south of 45° latitude on North-Atlantic rocky shores by 2200 because of climate change. The extent of predicted habitat loss, however, could be mitigated if the seaweeds' physiology is sufficiently plastic to rapidly acclimatize to the warmer temperatures. The main objectives of this study were to identify whether the thermal tolerance of the canopy-forming seaweed Fucus serratus is population-specific and where temperatures are likely to exceed its tolerance limits in the next 200 years. We measured the stress response of seaweed samples from four populations (Norway, Denmark, Brittany and Spain) to common-garden heat stress (20 °C-36 °C) in both photosynthetic performance and transcriptomic upregulation of heat shock protein genes. The two stress indicators did not correlate and likely measured different cellular components of the stress response, but both indicators revealed population-specific differences, suggesting ecotypic differentiation. Our results confirmed that thermal extremes will regularly reach physiologically stressful levels in Brittany (France) and further south by the end of the 22nd century. Although heat stress resilience in photosynthetic performance was higher at the species' southern distributional edge in Spain, the hsp expression pattern suggested that this edge-population experienced reduced fitness and limited responsiveness to further stressors. Thus, F. serratus may be unable to mitigate its predicted northward shift and may be at high risk to lose its center of genetic diversity and adaptability in Brittany (France). As it is an important intertidal key species, the disappearance of this seaweed will likely trigger major ecological changes in the entire associated ecosystem., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The North-Atlantic has warmed faster than all other ocean basins and climate change scenarios predict sea surface temperature isotherms to shift up to 600 km northwards by the end of the 21st century. The pole-ward shift has already begun for many temperate seaweed species that are important intertidal foundation species. We asked the question: Where will climate change have the greatest impact on three foundational, macroalgal species that occur along North-Atlantic shores: Fucus serratus, Fucus vesiculosus, and Ascophyllum nodosum? To predict distributional changes of these key species under three IPCC (Intergovernmental Panel on Climate Change) climate change scenarios (A2, A1B, and B1) over the coming two centuries, we generated Ecological Niche Models with the program MAXENT. Model predictions suggest that these three species will shift northwards as an assemblage or "unit" and that phytogeographic changes will be most pronounced in the southern Arctic and the southern temperate provinces. Our models predict that Arctic shores in Canada, Greenland, and Spitsbergen will become suitable for all three species by 2100. Shores south of 45° North will become unsuitable for at least two of the three focal species on both the Northwest- and Northeast-Atlantic coasts by 2200. If these foundational species are unable to adapt to the rising temperatures, they will lose their centers of genetic diversity and their loss will trigger an unpredictable shift in the North-Atlantic intertidal ecosystem.

Objective: Oppositional defiant disorder (ODD) is the most common comorbid condition in childhood ADHD. This trial was prospectively designed to explore ODD symptoms in ADHD adults., Method: A total of 86 patients in this placebo-controlled, double-blind trial of methylphenidate transdermal system (MTS) were categorized based on the presence of ODD symptoms in childhood and adulthood, and then were compared for baseline and outcome differences., Results: In all, 42% met Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) criteria for ODD as adults and were significantly more impaired on measures of ADHD, personality disorder, and substance abuse and 27% had childhood ODD that had resolved. Childhood and adult ODD symptoms were significantly correlated. ODD and ADHD symptoms improved significantly with MTS (p < .001), and the most consistently significant results were found in participants with adult ODD., Conclusion: A total of 69% met criteria for ODD as children and/or adults. Understanding how ODD interacts with ADHD to impact personality disorder, substance abuse, and treatment response has important clinical, social, and theoretical implications.

One of the most striking patterns observed among animals is that smaller-bodied taxa are generally much more diverse than larger-bodied taxa. This observation seems to be explained by the mere fact that smaller-bodied taxa tend to have an older evolutionary origin and have therefore had more time to diversify. A few studies, based on the prevailing null model of diversification (i.e. the stochastic constant-rate birth-death model), have suggested that this is indeed the correct explanation, and body-size dependence of speciation and extinction rates does not play a role. However, there are several potential shortcomings to these studies: a suboptimal statistical procedure and a relatively narrow range of body sizes in the analysed data. Here, we present a more coherent statistical approach, maximizing the likelihood of the constant-rate birth-death model with allometric scaling of speciation and extinction rates, given data on extant diversity, clade age and average body size in each clade. We applied our method to a dataset compiled from the literature that includes a wide range of Metazoan taxa (range from midges to elephants). We find that the higher diversity among small animals is indeed, partly, caused by higher clade age. However, it is also partly caused by the body-size dependence of speciation and extinction rates. We find that both the speciation rate and extinction rate decrease with body size such that the net diversification rate is close to 0. Even more interestingly, the allometric scaling exponent of speciation and extinction rates is approximately -0.25, which implies that the per generation speciation and extinction rates are independent of body size. This suggests that the observed relationship between diversity and body size pattern can be explained by clade age alone, but only if clade age is measured in generations rather than years. Thus, we argue that the most parsimonious explanation for the observation that smaller-bodied taxa are more diverse is that their evolutionary clock ticks faster.

Objective: This trial was designed to prospectively explore the relationship among personality disorder (PD) symptoms, attention-deficit/hyperactivity disorder (ADHD), and treatment response in a randomized, double-blind, crossover clinical trial of methylphenidate transdermal system (MTS) and to confirm results of a prior exploratory study., Method: 67 adults who met the Utah and/or DSM-IV-TR criteria for ADHD were recruited with no attempt to include or exclude patients with PD. Responders were defined by a 50% improvement on the Wender-Reimherr Adult Attention Deficit Disorder Scale (WRAADDS), the primary outcome measure. Personality disorder was diagnosed by the clinicians using the Structured Clinical Interview for DSM-IV-TR Axis II Personality Disorders Questionnaire, several self-report scales, and clinical observations. Subjects were categorized as: no PD (PD-negative), 1 PD (PD-positive), and 2 or more PDs (PD-plus). The study was conducted from February 2007 to December 2009 at the Mood Disorders Clinic at the University of Utah School of Medicine, Salt Lake City., Results: 37% (n = 25) were PD-positive, and another 27% (n = 18) were PD-plus. In those with a PD, 65% (n = 28) had a cluster C diagnosis, 44% (n = 19) cluster B, and 5% (n = 12) cluster A. PD-plus subjects had significantly higher levels of oppositional defiant disorder (ODD) symptoms (P = .007) and emotional dysregulation (P = .004). 71% (15/21) of the PD-positive and PD-negative subjects were responders in the MTS arm (P < .001) as opposed to 38% (6/16) of the PD-plus subjects (P = .24). Conversely, the interaction between treatment (placebo versus MTS) and the 3 PD groups was not statistically significant (P = .46) when the total WRAADDS was used as the outcome measure., Conclusions: Personality disorder status was associated with more complex ADHD, especially high levels of emotional dysregulation and ODD symptoms. There was a significant treatment effect for PD-positive and PD-negative, but not PD-plus subjects., Trial Registration: ClinicalTrials.gov identifier: NCT00506285.

Predicted global climate change threatens the distributional ranges of species worldwide. We identified genes expressed in the intertidal seagrass Zostera noltii during recovery from a simulated low tide heat-shock exposure. Five Expressed Sequence Tag (EST) libraries were compared, corresponding to four recovery times following sub-lethal temperature stress, and a non-stressed control. We sequenced and analyzed 7009 sequence reads from 30min, 2h, 4h and 24h after the beginning of the heat-shock (AHS), and 1585 from the control library, for a total of 8594 sequence reads. Among 51 Tentative UniGenes (TUGs) exhibiting significantly different expression between libraries, 19 (37.3%) were identified as 'molecular chaperones' and were over-expressed following heat-shock, while 12 (23.5%) were 'photosynthesis TUGs' generally under-expressed in heat-shocked plants. A time course analysis of expression showed a rapid increase in expression of the molecular chaperone class, most of which were heat-shock proteins; which increased from 2 sequence reads in the control library to almost 230 in the 30min AHS library, followed by a slow decrease during further recovery. In contrast, 'photosynthesis TUGs' were under-expressed 30min AHS compared with the control library, and declined progressively with recovery time in the stress libraries, with a total of 29 sequence reads 24h AHS, compared with 125 in the control. A total of 4734 TUGs were screened for EST-Single Sequence Repeats (EST-SSRs) and 86 microsatellites were identified., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Objective: This trial evaluated the effect of methylphenidate transdermal system (MTS) on the full spectrum of adult symptoms (attention-disorganization, hyperactivity-impulsivity, emotional dysregulation [ED], and oppositional-defiant disorder [ODD]) found in this disorder., Method: This placebo-controlled, double-blind, flexible-dose, crossover trial employed the Wender-Reimherr Adult Attention Deficit Disorder Scale (WRAADDS) and Connor's Adult ADHD Rating Scale (CAARS) and two measures of adult ODD. Treatment responses of all participants and four subgroups (ADHDalone, ADHD + ED, ADHD + ODD, and ADHD + ED + ODD) were assessed., Results: Around 23% of baseline participants were ADHD alone, 31% were ADHD + ED, 10% were ADHD + ODD, and 36% were ADHD + ED + ODD. There was a significant treatment effect for all symptom areas and all four subgroups. MTS was associated with significantly more adverse events, especially dermatologic side effects., Conclusions: MTS was effective in treating adult ADHD. This clinical trial included numerous participants meeting criteria for ED and ODD. All ADHD symptoms responded positively to treatment with MTS.

Bioremediation of contaminated soils often leaves a desorption-resistant pollutant fraction behind in the soil, which in the present study was isolated with a combination of diffusive carrier and infinite diffusive sink. Such a diffusive sink was made by casting a composite of silicone and activated carbon into the bottom of a large glass. Field-contaminated soil samples were then suspended in a cyclodextrin solution and incubated in such glasses for the continuous trapping of PAH molecules during their release from the soil matrix. The PAH concentrations remaining in the soil were determined by exhaustive extraction and compared with a biodegradation experiment. The concentration decline in the first soil was faster in the contaminant trap than in the biodegradation experiment, but the halting of the biodegradation process before reaching the legal threshold level was well indicated by the contaminant trap. The PAH concentrations in the second soil hardly decreased in the traps at all, in good agreement with the biodegradation experiment. The PAHs in this soil appeared to be "stuck" by strong sorption. The contaminant trap proved to be a practical approach to the isolation and quantification of the desorption-resistant PAH fraction.

Detecting natural selection in wild populations is a central challenge in evolutionary biology and genomic scans are an important means of detecting allele frequencies that deviate from neutral expectations among marker loci. We used nine anonymous and 15 EST-linked microsatellites, 362 AFLP loci, and several neutrality tests, to identify outlier loci when comparing four populations of the seaweed Fucus serratus spaced along a 12km intertidal shore with a steep salinity gradient. Under criteria of at least two significant tests in at least two population pairs, three EST-derived and three anonymous loci revealed putative signatures of selection. Anonymous locus FsB113 was a consistent outlier when comparing least saline to fully marine sites. Locus F37 was an outlier when comparing the least saline to more saline areas, and was annotated as a polyol transporter/putative mannitol transporter - an important sugar-alcohol associated with osmoregulation by brown algae. The remaining loci could not be annotated using six different data bases. Exclusion of microsatellite outlier loci did not change either the degree or direction of differentiation among populations. In one outlier test, the number of AFLP outlier loci increased as the salinity differences between population pairs increased (up to 14); only four outliers were detected with the second test and only one was consistent with both tests. Consistency may be improved with a much more rigorous approach to replication and/or may be dependent upon the class of marker used., (Copyright © 2010 Elsevier B.V. All rights reserved.)

We examined 733 individuals of Fucusspiralis from 21 locations and 1093 Fucusvesiculosus individuals from 37 locations throughout their northern hemisphere ranges using nuclear and mitochondrial markers. Three genetic entities of F. spiralis were recovered. In northern and sympatric populations, the presence of "F. spiralis Low" in the mid-intertidal and "F. spiralis High" in the high-intertidal was confirmed and both co-occurred with the sister species F. vesiculosus. The third and newly-discovered entity, "F. spiralis South", was present mainly in the southern range, where it did not co-occur with F. vesiculosus. The South entity diverged early in allopatry, then hybridized with F. vesiculosus in sympatry to produce F. spiralis Low. Ongoing parallel evolution of F. spiralis Low and F. spiralis High is most likely due to habitat preference/local selection and maintained by preferentially selfing reproductive strategies. Contemporary populations of F. spiralis throughout the North Atlantic stem from a glacial refugium around Brittany involving F. spiralis High; F. spiralis South was probably unaffected by glacial episodes. Exponential population expansion for F. vesiculosus began during the Cromer and/Holstein interglacial period (300,000-200,000 yrs BP). Following the last glacial maximum (30,000-22,000 yrs BP), a single mtDNA haplotype from a glacial refugium in SW Ireland colonized Scandinavia, the Central Atlantic islands, and the W Atlantic., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Background: Seagrasses are a polyphyletic group of monocotyledonous angiosperms that have adapted to a completely submerged lifestyle in marine waters. Here, we exploit two collections of expressed sequence tags (ESTs) of two wide-spread and ecologically important seagrass species, the Mediterranean seagrass Posidonia oceanica (L.) Delile and the eelgrass Zostera marina L., which have independently evolved from aquatic ancestors. This replicated, yet independent evolutionary history facilitates the identification of traits that may have evolved in parallel and are possible instrumental candidates for adaptation to a marine habitat., Results: In our study, we provide the first quantitative perspective on molecular adaptations in two seagrass species. By constructing orthologous gene clusters shared between two seagrasses (Z. marina and P. oceanica) and eight distantly related terrestrial angiosperm species, 51 genes could be identified with detection of positive selection along the seagrass branches of the phylogenetic tree. Characterization of these positively selected genes using KEGG pathways and the Gene Ontology uncovered that these genes are mostly involved in translation, metabolism, and photosynthesis., Conclusions: These results provide first insights into which seagrass genes have diverged from their terrestrial counterparts via an initial aquatic stage characteristic of the order and to the derived fully-marine stage characteristic of seagrasses. We discuss how adaptive changes in these processes may have contributed to the evolution towards an aquatic and marine existence.

Background and Aims: The dwarf eelgrass, Zostera noltii, is a predominant inhabitant of soft-bottom intertidal regions along the coasts of northern Europe. It is a monoecious, protogynous angiosperm in which the potential for self-fertilization and inbreeding are high, especially if clone sizes exceed pollen dispersal distances. The aim of the present study was to determine the relationship between mating system and clonal structure, examine the relative roles of geitonogamous selfing and biparental inbreeding, measure pollen availability (multiple paternities) and estimate pollen dispersal., Methods: A 100-m(2) plot was established in a large, intertidal Z. noltii meadow on the island of Sylt in the German Wadden Sea. A total of 256 adult shoots was sampled: one from the centre of 100 fixed 1-m(2) quadrats (large scale resolution) and an additional 156 from within eight randomly selected 1-m(2) sub-quadrats (small-scale resolution). DNA was extracted from seeds and leaf tissue of all samples and genotyped with nine microsatellite loci., Key Results: Mating system analysis revealed high multilocus and single locus outcrossing rates. Average pollen dispersal distance was nearly the same as the average genet (clone) size. Multiple paternity was common and 20-30 % of mature seeds originated from matings within the plot. Among inbred seeds, most resulted from geitonogamy rather than biparental inbreeding., Conclusions: Moderate disturbances intrinsic to the intertidal habitat appear to facilitate seed recruitment by gap formation. Pollen dispersal distances are sufficient to maintain outcrossing and high clonal diversity.

Stress regimes defined as the synchronous or sequential action of abiotic and biotic stresses determine the performance and distribution of species. The natural patterns of stress to which species are more or less well adapted have recently started to shift and alter under the influence of global change. This was the motivation to review our knowledge on the stress ecology of a benthic key player, the macroalgal genus Fucus. We first provide a comprehensive review of the genus as an ecological model including what is currently known about the major lineages of Fucus species with respect to hybridization, ecotypic differentiation and speciation; as well as life history, population structure and geographic distribution. We then review our current understanding of both extrinsic (abiotic/biotic) and intrinsic (genetic) stress(es) on Fucus species and how they interact with each other. It is concluded that (i) interactive stress effects appear to be equally distributed over additive, antagonistic and synergistic categories at the level of single experiments, but are predominantly additive when averaged over all studies in a meta-analysis of 41 experiments; (ii) juvenile and adult responses to stress frequently differ and (iii) several species or particular populations of Fucus may be relatively unaffected by climate change as a consequence of pre-adapted ecotypes that collectively express wide physiological tolerences. Future research on Fucus should (i) include additional species, (ii) include marginal populations as models for responses to environmental stress; (iii) assess a wider range of stress combinations, including their temporal fluctuations; (iv) better differentiate between stress sensitivity of juvenile versus adult stages; (v) include a functional genomic component in order to better integrate Fucus' ecological and evolutionary responses to stress regimes and (vi) utilize a multivariate modelling approach in order to develop and understand interaction networks., (2011 Elsevier Ltd. All rights reserved.)

In order to aid gene discovery and uncover genes responding to abiotic stressors in stress-tolerant brown algae of the genus Fucus, expressed sequence tags (ESTs) were studied in two species, Fucus serratus and Fucus vesiculosus. Clustering of over 12,000 ESTs from three libraries for heat shock/recovery and desiccation/rehydration resulted in identification of 2,503, 1,290, and 2,409 unigenes from heat-shocked F. serratus, desiccated F. serratus, and desiccated F. vesiculosus, respectively. Low overall annotation rates (18-31%) were strongly associated with the presence of long 3' untranslated regions in Fucus transcripts, as shown by analyses of predicted protein-coding sequence in annotated and nonannotated tentative consensus sequences. Posttranslational modification genes were overrepresented in the heat shock/recovery library, including many chaperones, the most abundant of which were a family of small heat shock protein transcripts, Hsp90 and Hsp70 members. Transcripts of LI818-like light-harvesting genes implicated in photoprotection were also expressed during heat shock in high light. The expression of several heat-shock-responsive genes was confirmed by quantitative reverse transcription polymerase chain reaction. However, candidate genes were notably absent from both desiccation/rehydration libraries, while the responses of the two species to desiccation were divergent, perhaps reflecting the species-specific physiological differences in stress tolerance previously established. Desiccation-tolerant F. vesiculosus overexpressed at least 17 ribosomal protein genes and two ubiquitin-ribosomal protein fusion genes, suggesting that ribosome function and/or biogenesis are important during cycles of rapid desiccation and rehydration in the intertidal zone and possibly indicate parallels with other poikilohydric organisms such as desiccation-tolerant bryophytes.

Anodic bonding of silicon to glass always involves heating the glass and device to high temperatures so that cations become mobile in the electric field. We present a simple way of bonding thin silicon samples to borosilicate glass by means of heating from the glass side while locally cooling heat-sensitive areas from the silicon side. Despite the high thermal conductivity of silicon, this method allows a strong anodic bond to form just millimeters away from areas essentially at room temperature.

A novel microfabricated chemical reactor for highly sensitive measurements of catalytic activity and surface kinetics is presented. The reactor is fabricated in a silicon chip and is intended for gas-phase reactions at pressures ranging from 0.1 to 5.0 bar. A high sensitivity is obtained by directing the entire gas flow through the catalyst bed to a mass spectrometer, thus ensuring that nearly all reaction products are present in the analyzed gas flow. Although the device can be employed for testing a wide range of catalysts, the primary aim of the design is to allow characterization of model catalysts which can only be obtained in small quantities. Such measurements are of significant fundamental interest but are challenging because of the low surface areas involved. The relationship between the reaction zone gas flow and the pressure in the reaction zone is investigated experimentally. A corresponding theoretical model is presented, and the gas flow through an on-chip flow-limiting capillary is predicted to be in the intermediate regime. The experimental data for the gas flow are found to be in good agreement with the theoretical model. At typical experimental conditions, the total gas flow through the reaction zone is around 3x10(14) molecules s(-1), corresponding to a gas residence time in the reaction zone of about 11 s. To demonstrate the operation of the microreactor, CO oxidation on low-area platinum thin film circles is employed as a test reaction. Using temperature ramping, it is found that platinum catalysts with areas as small as 15 microm(2) are conveniently characterized with the device.

Background: Reef-building corals live in symbiosis with a diverse range of dinoflagellate algae (genus Symbiodinium) that differentially influence the fitness of the coral holobiont. The comparative role of symbiont type in holobiont fitness in relation to host genotype or the environment, however, is largely unknown. We addressed this knowledge gap by manipulating host-symbiont combinations and comparing growth, survival and thermal tolerance among the resultant holobionts in different environments., Methodology/principal Findings: Offspring of the coral, Acropora millepora, from two thermally contrasting locations, were experimentally infected with one of six Symbiodinium types, which spanned three phylogenetic clades (A, C and D), and then outplanted to the two parental field locations (central and southern inshore Great Barrier Reef, Australia). Growth and survival of juvenile corals were monitored for 31-35 weeks, after which their thermo-tolerance was experimentally assessed. Our results showed that: (1) Symbiodinium type was the most important predictor of holobiont fitness, as measured by growth, survival, and thermo-tolerance; (2) growth and survival, but not heat-tolerance, were also affected by local environmental conditions; and (3) host population had little to no effect on holobiont fitness. Furthermore, coral-algal associations were established with symbiont types belonging to clades A, C and D, but three out of four symbiont types belonging to clade C failed to establish a symbiosis. Associations with clade A had the lowest fitness and were unstable in the field. Lastly, Symbiodinium types C1 and D were found to be relatively thermo-tolerant, with type D conferring the highest tolerance in A. millepora., Conclusions/significance: These results highlight the complex interactions that occur between the coral host, the algal symbiont, and the environment to shape the fitness of the coral holobiont. An improved understanding of the factors affecting coral holobiont fitness will assist in predicting the responses of corals to global climate change.

Eukaryotic mitochondria are mostly uniparentally (maternally) inherited, although mtDNA heteroplasmy has been reported in all major lineages. Heteroplasmy, the presence of more than one mitochondrial genome in an individual, can arise from recombination, point mutations, or by occasional transmission of the paternal mtDNA (=paternal leakage). Here, we report the first evidence of mtDNA paternal leakage in brown algae. In Denmark, where Fucus serratus L. and Fucus evanescens C. Agardh have hybridized for years, we found eight introgressed individuals that possessed the very distinct haplotypes of each parental species. The finding of heteroplasmy in individuals resulting from several generations of backcrosses suggests that paternal leakage occurred in earlier generations and has persisted through several meiotic bottlenecks., (© 2009 Phycological Society of America.)

Early invasions of the North American shore occurred mainly via deposition of ballast rock, which effectively transported pieces of the intertidal zone across the Atlantic. From 1773-1861, >880 European ships entered Pictou Harbor, Nova Scotia, as a result of emigration and trade from Europe. The rockweed Fucus serratus (1868) and the snail Littorina littorea ( approximately 1840) were found in Pictou during this same period. With shipping records (a proxy for propagule pressure) to guide sampling, we used F. serratus as a model to examine the introductions because of its relatively low genetic diversity and dispersal capability. Microsatellite markers and assignment tests revealed 2 introductions of the rockweed into Nova Scotia: 1 from Galway (Ireland) to Pictou and the other from Greenock (Scotland) to western Cape Breton Island. To examine whether a high-diversity, high-dispersing species might have similar pathways of introduction, we analyzed L. littorea, using cytochrome b haplotypes. Eight of the 9 Pictou haplotypes were found in snails collected from Ireland and Scotland. Our results contribute to a broader understanding of marine communities, because these 2 conspicuous species are likely to be the tip of an "invasion iceberg" to the NW Atlantic from Great Britain and Ireland in the 19th Century.

The seaweed genus Fucus is a dominant component of intertidal shores throughout the North Atlantic and North Pacific and has been the focus of considerable developmental, ecological, and evolutionary research for the past century. Here, we present details of 21 expressed sequence tag-derived simple sequence repeat markers (microsatellites). All 21 were polymorphic for F. serratus, which also display considerable cross-reactivity with the sister species F. distichus (18) and the more distantly related F. vesiculosus (13), and F. spiralis (5)., (© 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Ltd.)