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— Myriopteris scabra (until recently called Cheilanthes horridula) is a xeric-adapted fern species, endemic to the southwestern United States and northern Mexico. It is one of the most recognizable ferns in North America due to the unusual nature of the indument present on its adaxial leaf surfaces. This consists of rigid, multicellular trichomes with glassy, needle-like apices and compact conical bodies that are partially embedded in the leaf surface to form swollen, pustulate bases. Despite the seemingly distinctive nature of M. scabra, published chromosome counts indicate that collections assigned to this taxon encompass both diploids (n = 29) and tetraploids (n = 58). Here we investigate this case of cryptic diversity by integrating data from cytogenetic and spore analyses, observations of sporophyte morphology, and geographic distributions. Myriopteris scabra s.l. is shown to comprise two genetically disparate, morphologically recognizable taxa that exhibit little or no geographic overlap. The tetraploid taxon is described as a new species, M. grusziae, which completely supplants diploid M. scabra in the northeastern portion of its range (central Texas and south-central Oklahoma). This presumed allotetraploid is most like M. scabra but differs in having ultimate segments with adaxial trichomes that are longer, more flexible, mostly linear, and superficially attached. In addition, tetraploid M. grusziae has larger, more abundant scales that largely conceal the dark, sclerified leaf rachises, and it produces consistently larger spores than diploid M. scabra. We hypothesize that M. grusziae is an allotetraploid hybrid that acquired half of its chromosomes from M. scabra. However, the identity of the other diploid parent has yet to be resolved.

PREMISE Apomixis (asexual reproduction by seed, spore, or egg) has evolved repeatedly across the tree of life. Studies of animals and angiosperms show that apomictic lineages are often evolutionarily short-lived and frequently exhibit different distributions than their sexual relatives. However, apomixis is rare in these groups. Less is known about the role of apomixis in the evolution and biogeography of ferns, in which ~10% of species are apomictic. Apomixis is especially common in the fern genus Pteris (34-39% of species); however, because of the limited taxonomic and geographic sampling of previous studies, the true frequency of apomixis and its associations with geography and phylogeny in this lineage remain unclear. METHODS We used spore analyses of herbarium specimens to determine reproductive mode for 127 previously unsampled Pteris species. Then we leveraged biogeographic and phylogenetic analyses to estimate the global distribution and evolution of apomixis in Pteris. RESULTS Among all Pteris species examined, we found that 21% are exclusively apomictic, 71% are exclusively sexual, and 8% have conflicting reports. Apomixis is unevenly distributed across the range of the genus, with the Paleotropics exhibiting the highest frequency, and has evolved numerous times across the Pteris phylogeny, with predominantly East Asian and South Asian clades containing the most apomictic species. CONCLUSIONS Apomixis arises frequently in Pteris, but apomictic species do not appear to diversify. Species that encompass both apomictic and sexual populations have wider ranges than exclusively sexual or apomictic species, which suggests that sexual and apomictic ferns could occupy separate ecological niches.

Premise Xeric environments impose major constraints on the fern life cycle, yet many lineages overcome these limitations by evolving apomixis. Here, we synthesize studies of apomixis in ferns and present an evidence-based model for the evolution and establishment of this reproductive strategy, focusing on genetic and environmental factors associated with its two defining traits: the production of "unreduced" spores (n = 2n) and the initiation of sporophytes from gametophyte tissue (i.e., diplospory and apogamy, respectively). Methods We evaluated existing literature in light of the hypothesis that abiotic characteristics of desert environments (e.g., extreme diurnal temperature fluctuations, high light intensity, and water limitation) drive the evolution of obligate apomixis. Pellaeid ferns (Cheilanthoideae: Pteridaceae) were examined in detail, as an illustrative example. We reconstructed a plastid (rbcL, trnG-trnR, atpA) phylogeny for the clade and mapped reproductive mode (sexual versus apomictic) and ploidy across the resulting tree. Results Our six-stage model for the evolution of obligate apomixis in ferns emphasizes the role played by drought and associated abiotic conditions in the establishment of this reproductive approach. Furthermore, our updated phylogeny of pellaeid ferns reveals repeated origins of obligate apomixis and shows an increase in the frequency of apomixis, and rarity of sexual reproduction, among taxa inhabiting increasingly dry North American deserts. Conclusions Our findings reinforce aspects of other evolutionary, physiological, developmental, and omics-based studies, indicating a strong association between abiotic factors and the establishment of obligate apomixis in ferns. Water limitation, in particular, appears critical to establishment of this reproductive mode.

International audience; This study compares molecular calculations performed with molecular and periodic codes through an investigation of the solvation structures of alkali and alkaline earth metal ions in tetraglyme solution. The two codes are able to produce equivalent structural and energetic information at the same level of theory, and in the presence of the implicit solvation model or not. This comparison reveals that molecular optimisations can be performed with periodic codes and used directly as input models for interface or electrochemistry calculations in order to preserve the solvent−solute interaction and the cavitation energy. By a rigorous comparison, we have demonstrated that equivalent energetic values can be obtained with the conventional PBE-D3 and the newly developed SCAN-rVV10 functional. Nevertheless, when the vibrational features are concerned and when the molecule possesses a highly conjugated system, the SCAN-rVV10 functional is required to describe the vibrational modes properly. The computed IR/Raman spectra can thus be used as essential information to determine the first solvation shell of metal ions in glyme-based solutions. In tetraglyme solution, the alkali and alkaline earth metal ions exhibit a diverse solvation structure. Small ions like Li+ and Mg2+ tend to adopt a coordination number of five or six, while larger ions, Na+, K+, and Ca2+, prefer an eight-coordinated environment, and the metal−ligand interaction increases in the order K+−O < Na+−O < Li+−O < Ca2+−O < Mg2+−O. The solvation spheres play a significant role in the stability and the reactivity of the solvated ions, and can thus be used as input models to construct the solvation structure in more sophisticated electrolytes, such as polyethylene oxide, or perform electrochemical calculations.

Abdominal-pelvic hemorrhage (i.e., originates below the diaphragm and above the inguinal ligaments) is a major cause of death. It has diverse etiology but is typically associated with gunshot or stab wounds, high force or velocity blunt trauma, aortic rupture, and peripartum bleeds. Because there are few immediately deployable, temporizing measures, and the standard approaches such as direct pressure, hemostatics, and tourniquets are less reliable than they are with compressible extremity injuries, risk for death resulting from abdominal-pelvic hemorrhage is high. This review concerns the exciting potential of proximal external aortic compression (PEAC) as a temporizing technique for life-threatening lower abdominal-pelvic hemorrhage. PEAC can be accomplished by means of a device, two locked arms (manual), or a single knee (genicular) to press over the midline supra-umbilical abdomen. The goal is to compress the descending aorta and slow or halt downstream hemorrhage while not delaying more definitive measures such as hemostatic packing, tourniquets, endovascular balloons, and ultimately operative repair.Clinical review of the Ovid MEDLINE, In-Process,Other Non-Indexed, and Google Scholar databases was performed for the period ranging from 1946 to 3 May 2019 for studies that included the following search terms: [proximal] external aortic compression OR vena cava compression AND (abdomen or pelvis) OR (hemorrhage) OR (emergency or trauma). In addition, references from included studies were assessed.Sixteen studies met the inclusion criteria. Evidence was grouped and summarized from the specialties of trauma, aortic surgery, and obstetrics to help prehospital responders and guide much-needed additional research, with the goal of decreasing the high risk for death after life-threatening abdominal-pelvic hemorrhage.

Food webs in temporary forest ponds are driven by decomposition of terrestrial inputs. Chytrid fungi are important components of the fungal community, degrading leaf litter in streams reliant on terrestrial inputs and in lake ecosystems where they may stabilize the food web. However, little is known about chytrid fungi in temporary forest ponds. We inventoried the chytrid diversity present in two temporary forest ponds via light microscopy of baited samples and ion semiconductor (Ion Torrent) sequencing of environmental DNA. We quantified trends of chytrid alpha and beta diversity as a function of spatial and temporal factors. A total of 59 chytrid taxa were detected throughout the study. Beta diversity exhibited variation across the sampled months for both the entire fungal community as well as for chytrids alone. Shifts in community composition were also apparent, although diversity metrics and composition patterns did not meet adjusted P values. The results of this study highlight the diversity of chytrid fungi in temporary forest ponds and the need for further studies on the spatial and temporal dynamics of chytrid species.

Despite nearly a century of study, the diversity of marine fungi remains poorly understood. Historical surveys utilizing microscopy or culture-dependent methods suggest that marine fungi are relatively species-poor, predominantly Dikarya, and localized to coastal habitats. However, the use of high-throughput sequencing technologies to characterize microbial communities has challenged traditional concepts of fungal diversity by revealing novel phylotypes from both terrestrial and aquatic habitats. Here, I used ion semiconductor sequencing (Ion Torrent) of the ribosomal large subunit (LSU/28S) to explore fungal diversity from water and sediment samples collected from four habitats in coastal North Carolina. The dominant taxa observed were Ascomycota and Chytridiomycota, though all fungal phyla were represented. Diversity was highest in sand flats and wetland sediments, though benthic sediments harbored the highest proportion of novel sequences. Most sequences assigned to early-diverging fungal groups could not be assigned beyond phylum with statistical support, suggesting they belong to unknown lineages.

Terrestrial fungi play critical roles in nutrient cycling and food webs and can shape macroorganism communities as parasites and mutualists. Although estimates for the number of fungal species on the planet range from 1.5 to over 5 million, likely fewer than 10% of fungi have been identified so far., Terrestrial fungi play critical roles in nutrient cycling and food webs and can shape macroorganism communities as parasites and mutualists. Although estimates for the number of fungal species on the planet range from 1.5 to over 5 million, likely fewer than 10% of fungi have been identified so far. To date, a relatively small percentage of described species are associated with marine environments, with ∼1,100 species retrieved exclusively from the marine environment. Nevertheless, fungi have been found in nearly every marine habitat explored, from the surface of the ocean to kilometers below ocean sediments. Fungi are hypothesized to contribute to phytoplankton population cycles and the biological carbon pump and are active in the chemistry of marine sediments. Many fungi have been identified as commensals or pathogens of marine animals (e.g., corals and sponges), plants, and algae. Despite their varied roles, remarkably little is known about the diversity of this major branch of eukaryotic life in marine ecosystems or their ecological functions. This perspective emerges from a Marine Fungi Workshop held in May 2018 at the Marine Biological Laboratory in Woods Hole, MA. We present the state of knowledge as well as the multitude of open questions regarding the diversity and function of fungi in the marine biosphere and geochemical cycles.

There is a paucity of data on long-term, spatially resolved changes in microbial diversity and biogeography in marine systems, and yet these organisms underpin fundamental ecological processes in the oceans affecting socio-economic values of the marine environment. We report results from a new autonomous Water and Microplankton Sampler (WaMS) that is carried within the Continuous Plankton Recorder (CPR). Whilst the CPR with its larger mesh size (270 μm), is designed to capture larger plankton, the WaMS was designed as an additional device to capture plankton below 50 μm and delicate larger species, often destroyed by net sampling methods. A 454 pyrosequencing and flow cytometric investigation of eukaryotic microbes using the partial 18S rDNA from thirteen WaMS samples collected over three months in the English Channel revealed a wide diversity of organisms. Alveolates, Fungi, and picoplanktonic Chlorophytes were the most common lineages captured despite the small sample volumes (200–250 ml). The survey also identified Cercozoa and MAST heterotrophic Stramenopiles, normally missed in microscopic-based plankton surveys. The most common was the likely parasitic LKM11 Rozellomycota lineage which comprised 43.2% of all reads and are rarely observed in marine pelagic surveys. An additional 9.5% of reads belonged to other parasitic lineages including marine Syndiniales and Ichthyosporea. Sample variation was considerable, indicating that microbial diversity is spatially or temporally patchy. Our study has shown that the WaMS sampling system is autonomous, versatile and robust, and due to its deployment on the established CPR network, is a cost-effective monitoring tool for microbial diversity for the detection of smaller and delicate taxa.

Symbiotic interactions between fungi and photosynthetic partners are common among derived fungal lineages. The only fungal-phototroph interactions thus far reported from the early diverging zoosporic fungi are parasitic in nature. Rhizidium phycophilum is a terrestrial, saprotrophic chytrid, which appears to be able to enter a facultative mutualism with a coccoid green alga in the absence of refractory organic material, such as pollen and chitin. Liquid and solid culturing methods were used in a series of differential fitness experiments in conjunction with microscopic analyses to characterize the interaction between R. phycophilum and the alga. The alga in this partnership is identified as a member of the genus Bracteacoccus. Under certain culturing conditions, algal cells grown in coculture with R. phycophilum were shown to grow larger and more prolifically than when cultured axenically under the same conditions. Additionally, dialysis experiments demonstrate that R. phycophilum does not parasitize Bracteacoccus sp., and can be cultured in media infused with unknown algal exudates. Rhizidium phycophilum and Bracteacoccus sp. represent the first facultative positive interaction between a zoosporic fungus and a photoautotroph and may prove a tractable system for modelling interactions between early fungi and plants.

Molecular and ultrastructural investigations are revealing unrealized diversity among chytrids as the taxonomic revision of order Chytridiales (Chytridiomycota) progresses. During a biodiversity survey of soil-inhabiting chytrids in Australia an undescribed chytrid was isolated from a soil sample collected in a cool temperate rainforest of New South Wales, Australia. Combined zoospore ultrastructure analysis and molecular phylogenetic analyses of partial LSU rRNA and ITS1-5.8S-ITS2 sequences demonstrated this chytrid was a new species within Chytridiales and possessed distinctive zoospore architecture previously unknown. Herein we delineate a new Rhizidium species in Chytridiales based on molecular monophyly and unique subcellular organization of the zoospore.

Rhizophlyctis rosea (Chytridiomycota) is an apparently ubiquitous, soil-inhabiting, cellulose-degrading chytrid that is the type for Rhizophlyctis. Previous studies have revealed multiple zoospore subtypes among morphologically indistinguishable isolates in the R. rosea complex sensu Barr. In this study we analysed zoospore ultrastructure and combined nu-rRNA gene sequences (partial LSU and complete ITS1-5.8S-ITS2) of 49 isolates from globally distributed soil samples. Based on molecular monophyly and zoospore ultrastructure, this group of Rhizophlyctis rosea-like isolates is designated as a new order, the Rhizophlyctidales. Within the Rhizophlyctidales are four new families (Rhizophlyctidaceae, Sonoraphlyctidaceae, Arizonaphlyctidaceae, and Borealophlyctidaceae) and three new genera (Sonoraphlyctis, Arizonaphlyctis, and Borealophlyctis).

Exposure of cells or animals to carcinogenic chromium(VI) (Cr(VI)) produces Cr(III)-DNA adducts. The relevance of these lesions to Cr(VI)-induced tumors is unclear. Various Cr(III) complexes have been used to model the products resulting from Cr(VI) metabolism in order to gain mechanistic insights. The purpose of this study was to characterize interactions of Cr(III) complexes with DNA in order to evaluate their use as models for these purposes. The reactivity of DNA with chromic chloride hexahydrate (CrCl(3)) and sodium bis(l-cysteinato)chromium(III) dihydrate (Cr(cys)(2)(-)) was compared to that with cis-diamminedichloroplatinum(II) (cis-platin). Both Cr(III) and Pt(II) cause unwinding of supercoiled DNA that can be visualized as a mobility shift by gel electrophoresis. Chromic chloride was much less distorting than cis-platin, unwinding DNA by only 1-2 degrees, and Cr(cys)(2)(-) interacted with DNA only weakly. Consistent with in vitro studies, CrCl(3) produced Cr-DNA adducts in CHO AA8 cells at levels equivalent to those obtained with Cr(VI), whereas Cr(cys)(2)(-) did not produce significant adducts. Lesions produced by CrCl(3) were not mutagenic in the hypoxanthine-Gua-phosphoribosyl-transferase assay. These data are consistent with CrCl(3) producing a nondistorting lesion, perhaps by association with the phosphate backbone. There are two possible interpretations of these results: Either the Cr(III) products formed by Cr(VI) metabolism are not modeled by CrCl(3) and Cr(cys)(2)(-) complexes, or Cr(III) is not an active species for Cr(VI)-induced DNA damage. This study provides the first structural evidence for Cr(III)-DNA adducts. A molecular understanding of Cr(III)-DNA interactions will be necessary before we can determine their relevance in Cr(VI)-induced cancers.

ObjectiveSubjective scales to assess agitation and sedation in adult intensive care unit (ICU) patients have rarely been tested for validity or reliability. We revised and prospectively tested the Sedation-Agitation Scale (SAS) for interrater reliability and compared it with the Ramsay scale and the

Lipid bodies, nonmembrane-bound cytoplasmic inclusions, serve as repositories of esterified arachidonate and are increased in cells associated with inflammatory reactions. We have evaluated stimuli and mechanisms responsible for lipid body formation within human polymorphonuclear leukocytes (PMNs). Arachidonic acid and oleic acid stimulated dose-dependent formation of lipid bodies over 0.5-1 h. Other C20 and C18 fatty acids were less active and demonstrated rank orders as follows: cis-unsaturated fatty acids were much more active than trans-fatty acids, and activity diminished with decreasing numbers of double bonds. Lipid bodies elicited in vitro with cis-fatty acids were ultrastructurally identical to lipid bodies present in PMNs in vivo. Lipid body induction was not because of fatty acid-elicited oxidants or fatty acid-induced ATP depletion. Cis-fatty acid-induced activation of protein kinase C (PKC) was involved in lipid body formation as evidenced by the capacity of other PKC activators, 1-oleoyl-2-acetyl-glycerol and two active phorbol esters, phorbol myristate acetate, and phorbol 12,13 dibutyrate, but not an inactive phorbol, to induce lipid body formation. The PKC inhibitor, 1-O-hexadecyl-2-O-methyl-glycerol, inhibited PMN lipid body formation induced by oleic and arachidonic acids and by 1-oleoyl-2-acetyl-glycerol and phorbol myristate acetate. Other PKC inhibitors (staurosporine, H-7) also inhibited lipid body formation. Formation of lipid bodies in PMNs is a specific cellular response, stimulated by cis-fatty acids and diglycerides and apparently mediated by PKC, which results in the mobilization and deposition of lipids within discrete, ultrastructurally defined cytoplasmic domains.

Transfusion therapy has been the mainstay for treating the anemia of end-stage renal disease (ESRD). Recently, several factors, including the awareness of associated risks, especially the transmission of blood-borne diseases and the transient treatment effect with regard to reversal of anemic symptoms, have caused a reassessment of transfusion therapy. Recombinant human erythropoietin (epoetin) has emerged as the alternative treatment, capable of sustained reversal of anemia without the associated risks of transfusions. The result of epoetin therapy has been marked improvement in the quality of life of ESRD patients. However, the advent of this therapy has also changed the nurse's role in caring for ESRD patients, as new medical management issues are identified and supportive care is tailored to the individual patient.

International audience; Ce volume propose une analyse lexicologique, axiologique et généalogique de la notion d’artifice dans les lettres et les arts. Les études couvrent une longue période (de la Grèce antique à nos jours) et concernent divers genres littéraires (récit, théâtre, poésie, essai, portrait, mémoires, roman, critique d’art), de nombreux arts (peinture, opéra, danse, musique, photographie, cinéma) et des domaines variés (rhétorique, esthétique, technologie, tactique militaire, pornographie).